BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to an ink jet recording head and manufacturing method
thereof, in particular relates to recording head and manufacturing method thereof,
and an ink jet recording apparatus.
[0002] The present invention also relates to a discharge opening (orifice) plate and manufacturing
method thereof, and an ink jet recording head with the plate, and an ink jet apparatus
with the head.
Related Background Art
[0003] As the liquid jet recording device of this type of the prior art, there have been
proposed various devices such as one in which fine droplets are discharged by generating
pressure difference in the liquid channel through deformation of a piezoelectric element
one in which a pair of electrodes are provided to deflect, or one in which droplets
are discharged from the discharging orifices by utilizing heat energy such as by generating
abruptly heat from the heat generating element arranged in the liquid channel, thereby
generating bubbles, etc.
[0004] Among them, the liquid jet recording head according to the system in which the recording
liquid is discharged by utilizing heat energy is particularly attracting attention
as one which is capable of recording of high resolving power because liquid discharging
outlets such as orifices for formation of droplets for flying by discharging droplets
for recording, etc., (hereinafter also called as "orifices") can be arranged at high
density, can be made compact as a whole as the recording head, can fully utilize the
recent technical progresses in the field of semiconductors as well as the advantages
of IC technique and microworking technique of which improvements of reliability are
marked, can be easily made lengthy and planar (dimensional), etc., whereby it can
be easily made into multi-nozzle and armored at high density, and yet productivity
during bulk production is good to make the production cost lower.
[0005] Figs. 1A and 1B are respectively a schematic exploded perspective view and a schematic
perspective after bonding showing an example of the liquid jet recording head of this
type of the prior art.
[0006] In these Figures, 1 is a first substrate comprising Si, etc., comprising a group
of electricity-heater converters and wiring portions thereof provided as the energy
generating element for generating the energy to be utilized for discharging liquid
on its upper surface. 8 is a second substrate, having an introducing inlet 9 for liquid
for recording such as ink (hereinafter merely called as "ink"), a groove 11A for forming
an ink flow channel 11 corresponding to the electricity heat converter, an ink flow
channel wall 10 and a concavity 12 which becomes the common liquid chamber for storing
ink and also communicating it to the respective flow channels formed thereon.
[0007] As shown in Fig. 1A, the first and the second substrates are mutually adhered and
fixed with an adhesive 13 to assemble a recording head as shown in Fig. 1B.
[0008] However, the head obtained by the method as described above has the problem that
the straight forward progress of the ink droplets is impaired. This is, above all,
due to the fact that the orifices, which are formed of materials of different qualities,
cause difference in wettability with the ink at the peripherals of orifices. In the
prior art, for the purpose of avoiding such problem, it has been proposed to prepare
separately an orifice plate comprising orifices molded by etching of a metal plate
or a photosensitive glass plate, or an orifice plate comprising orifices by hole working
on a resin film, etc., and plastering it onto the main head.
[0009] However, in the liquid recording head with such constitution (hereinafter also called
"ink jet recording head" or merely "recording head"), there ensued the following problems.
[0010] In the ink jet recording head as described above, the step of bonding an orifice
plate is included during its preparation, and it is necessary to perform strictly
registration between the orifice and the flow channel portion during said bonding.
Also, since said bonding can be done with difficulty when the end surfaces of the
first and the second substrate to be bonded to the orifice plate are not coincident
in plane, difficulty can also ensue during adhesion of the both substrates for this
reason.
[0011] In addition, the orifice plate is also adhered by use of an adhesive, but since the
pitch of the flow channel 11 and the height of the flow channel wall 10 are fine to
the extent of about some 10 µm, unless the coated amount (thickness) of the adhesive
layer 13 is controlled to about some µm, the adhesive may come out to the flow channel
side because of the pressure applied during bonding, whereby there may be caused such
fear that the low channel diameter or the discharging orifice diameter may be varied,
even to leading to clogging. Also, when the adhesive force is not sufficient, there
is the fear that peeling of the orifice plate may occur.
[0012] Further, in the orifice plate by use of a resin film, because the resin film has
generally a thickness of about 20 to 50 µm, not only handling is cumbersome, but also
it may be considered that wrinkles may be formed or bubbles may be introduced during
plastering to effect no good plastering.
[0013] The complicatedness of the preparation steps and the large number of steps as described
above bring about increase in the production cost of recording head, and this has
been also a problem in making the recording head as described above, or the recording
head constituted by integration with an ink tank, etc. which is the ink supplying
source disposable.
[0014] The contents as described above are to be described in more detail as follows. The
ink jet recording head is constituted of an orifice plate 40 having orifices 41 as
the discharging outlet, a ceiling plate 400 having ink channel grooves 401 communicated
to the respective orifices, and a heater board 100A constituting a part of the ink
channel and having energy generating elements 101 for generating energy to be utilized
for discharging ink, as shown in Fig. 2.
[0015] Generally speaking, the orifice plate is provided for the purpose of constituting
the discharging outlet surface of the same member in order to prevent slippage in
the discharging direction of discharged ink droplet caused by the difference in wettability
between the heater board and the ceiling plate, and also the orifice, including its
shape, etc. is an important element influencing the discharging performance of the
ink jet recording head. Above all, the orifice through the ink is discharged becomes
the most important portion, and with high developments of the image recording technique
and the recording head production technique in recent years as described above, the
orifice size (orifice diameter) has become miniaturized and a plurality of orifices
have become provided at high density.
[0016] On the other hand, various contrivances have been made in the prior art for working
of orifice. Some examples are mentioned below:
1) mechanical working with drill;
2) fine working by discharging working;
3) fine working by anisotropic etching of Si;
4) the method by patterning according to photolithography and plating;
5) fine working with carbon dioxide, YAG laser, etc.
[0017] However, as described above, the recording technique at the present time demands
higher precision and higher speed as a matter of course, and along with this demand,
the dimension of the orifice of the ink jet recording head has been miniaturized,
and the orifice density high, and yet the head has become to have a plurality of orifices.
[0018] In such point of view, according to the methods of prior art examples 1) and 2) as
mentioned above, there were involved such problems that miniaturization of orifice
dimension was difficult, and also that the efficiency was not good in working of a
plurality of
[0019] orifices of high density. On the other hand, in the method of 3), there was the problem
that the cost of Si material for the orifice plate was high in cost, and the working
time was long.
[0020] Further, in the method of 4), the preparation steps from photolithography to plating
are long, and also auxiliary materials such as substrate and resist, etc. must be
employed.
[0021] In addition, the method of 5) could not prepare a satisfactory orifice complying
with the above demand for the reason as described below.
[0022] Working by carbon dioxide laser and YAG laser was not sufficient in laser output,
and both shape and precision of the orifice formed were not satisfactory. For example,
the orifice formed by YAG laser is not circular in shape, and also foreign matters
not sufficiently removed by laser are attached around the orifice. Also depending
on the material and the thickness of the orifice plate, it also sometimes happened
that no orifice, namely opening portion could be formed.
[0023] Also, since working by carbon dioxide laser and YAG laser is done by working orifices
one by one, it is time consuming for working of a plurality of orifices and not suitable
for bulk productivity.
[0024] Further, although a plurality of orifices must be correct in each positional precision,
working was more difficult, because a movable portion for enabling also registration
precisely was also required in working by carbon dioxide laser and YAG laser of the
prior art.
[0025] As described above, according to the methods of the prior art, the respective problems
were involved in the above-mentioned demand, and they were not sufficiently satisfactory
as the working method of orifices.
[0026] On the other hand, recording by an ink jet recording head corresponds to higher precision,
higher speed as described above, and improvement of its reliability has also become
important. Accordingly, improvements have been also done to ink. As a consequence,
since the material in contact with ink is demanded to have ink resistance performance,
the material which becomes the orifice plate is also required to satisfy such demand.
Therefore, orifice working may be sometimes difficult depending on its material.
[0027] Also, the ink jet recording head is constituted of an orifice plate, a ceiling plate
and a substrate as described above. Above all, orifices and ink channels communicated
thereto, when no correctly registered in their positions, will badly affect discharging
performance, even causing non-discharging in the worst case.
[0028] However, since both orifices and ink channels are fine in their sizes and constituted
at high densities, and therefore it is difficult to assemble with correct registration,
thus posing a great problem in preparation of ink jet recording head.
[0029] The above content can be explained below from different aspect.
[0030] As mentioned above, the main body of the ink jet recording head comprised of, for
example as shown in Fig. 2, the orifice plate 40 having the orifice 41 (discharge
plate), the ceiling plate for forming the ink liquid path communicated with each orifice,
and the base member constituting a part of the path 401 and having the electro-mechanical
converting element 101A for generating energy used for discharging the ink.
[0031] The orifice plate has a fine orifice for discharging the ink, which orifice has great
significance affecting the discharge character of the ink jet recording head. In detail,
it is necessary for the orifice plate of the ink jet recording head to be excellent
in workability since fine orifice is provided, and excellent in ink-proof character
since it is directly contacted with the ink.
[0032] Conventionally, the metallic plate of SnS, Ni, Cr, Al, and resin film material such
as polyimide (PI), polyethersulfone (PES) polyetheretherketone (PEEK), and polyester
(PE) which can be formed easily in predetermined thickness and in low cost can be
used.
[0033] On the other hahd, the recording of high speed and very fine has been required in
these days as the progress of the recording technique, and for this reason the orifice
is formed in small in diameter and with high density. Consequently, there have been
adopted various kinds of working method for the orifice, among of which one using
the laser light is used for orifice forming since it is suitable for fine working.
[0034] However, it is very difficult to connect the perforated orifice plate and the corresponding
ink liquid path, and positional shift or offset therebetween is generated to deteriorate
the discharge quality as well as recording character. In addition, the adhesive used
for connection might go into the liquid path due to positional shift.
[0035] To add further, as the ink jet recording head utilizing a discharging orifice plate,
for example, those with constitutions shown in Figs. 3A to 3C and Figs. 4A and 4B
have been known.
[0036] The recording head with the constitution shown in Fig. 3 has a constitution obtained
by providing, for example, an ink channel wall 7A comprising a cured film of a photosensitive
resin, etc. as shown in Fig. 3B and an outer frame 8 constituting liquid chamber,
etc. on a substrate 100 comprising a glass, etc. having an energy generating member
101A for generating the energy to be utilized for discharging ink such as a heat generating
element, a piezoelectric element, etc. as shown in Fig. 3A, then bonding a cover 11B
for ink passages having ink feeding holes 9A thereto, further cutting the channel
downstream portion of the bonded body obtained (the main recording head portion) along
the line C - C to control the channel length, followed by bonding of a discharging
orifice plate 40 having thru-holes for formation of discharging orifices as shown
in Fig. 3C to the channel opening end surface formed by said cutting in predetermined
positional relationship.
[0037] On the other hand, the recording head with the constitution shown in Fig. 4A has
a constitution obtained by forming a main recording head portion provided with an
ink channel wall 7A, comprising, for example, a cured resin film of a photosensitive
resin, etc. and an outer frame 8A, as shown in Fig. 4B on a substrate 100 comprising
a glass, etc. having an ink discharging energy generating member 101A generating energy
used for discharging ink such as heat-generating element, piezoelectric element, etc.
as shown in Fig. 4A, and bonding a discharging orifice plate 12A to the upper part
thereof in predetermined positional relationship.
[0038] The constitution of the discharging orifice plate for constituting the ink jet recording
head with the constitution as described above and the characteristics to ink have
great influences on the recording characteristics of the ink jet recording head such
as the discharging direction of ink, the amount of the ink discharged, etc., and various
investigations have been done in the prior art about the material to be used for formation
of the discharging material and its structure.
[0039] Concerning the characteristics of the discharging plate in the prior art, the problems
to be solved may include the following problems.
a) In bonding between the discharging orifice plate and the main recording head portion,
it is necessary to coat an adhesive on the bonding surface on the main portion side,
but it is difficult to coat the adhesive uniformly, efficiently and with good workability
onto the bonding surface on the main portion side, and yet the adhesive is liable
to come around into the flow channel portion, whereby the production yield is low
to be poor in bulk productivity.
Further, when coating of the adhesive is carried out so that the adhesive may not
flow into the flow channel, the adhesive cannot be supplied to the peripheral portion
of the flow channel in most cases, and if bonding is effected under such state with
the discharging orifice plate, a gap will be formed between the discharging plate
and the main portion, wherein ink may be pooled to cause readily interference with
stable ink discharging.
b) In the case of providing a liquid repellent (ink repellent) coating layer for obtaining
good ink discharged state on the surface of the discharging orifice plate which becomes
the outer wall surface when bonded to the recording head (the surface on the side
where ink is discharged, hereinafter called "discharging orifice surface"), it is
difficult to coat uniformly the material for liquid repellent coating layer onto said
surface, and also it is difficult to inhibit flowing of the material for formation
of liquid repellent coating layer to the inner surface of the discharging orifice
which is demanded to be inkphillic, whereby the product yield is low to be poor in
productivity.
[0040] Also, as described above, the ink jet head to be applied to the ink jet recording
device is provided generally with an ink energy discharging member, ink channels,
ink discharging orifices and a liquid chamber of ink.
[0041] The output according to ink jet recording device is now demanded to be higher in
resolving power and speed, and as the means for solving this, improvements of pitch
precision and diameter precision of discharging orifice, and further ink repellent
treatment in the vicinity of discharging orifice may be mentioned. For preparation
of such ink jet head, there has been employed the method in which first fine grooves
are formed on a substrate such as glass, metal, plastic, etc., the substrate is bonded
to an appropriate plate to form liquid channels for ink within the head, and then
a discharging orifice plate having holes, pitches precisely worked by electroforming,
etching, etc. is bonded, followed by application of ink repellent treatment on the
whole plate surface.
[0042] The ink jet prepared according to the method of the prior art as described above
has problems in preparation during bonding of the discharging orifice plate and during
ink repellent treatment. In short, during bonding of the discharging orifice plate,
generally a means of coating the plate back surface or the front surface of the ink
channel with an adhesive and bonding the both is employed, but during coating of the
adhesive, there ensues the problem that a part or all of the ink channel or the discharging
orifice portion finely worked is filled with the adhesive. Further, during ink repellent
treatment, it is generally practiced to attach a fluorine type or silicon type thin
film on the whole plate surface, and also at this time, the phenomenon of collapsing
of hole similarly occurs as during coating of the adhesive as described above. Also,
in aspect of preparation cost, there is the problem that electroforming or etching
is expensive.
[0043] To say repeatedly, an ink jet recording head having a discharging orifice plate formed
with provision of thru-holes on a plate material has, for example, a representative
constitution as shown in Fig. 5.
[0044] More specifically, it has a structure comprising a discharging orifice plate 40 having
discharging orifices 41 communicated to the channel bonded to the opened face thereat
a bonded body having a substrate 100 provided with an energy generating member 101A
formed by wall member 7A for generating the energy to be utilized for discharging
ink within the ink channel and a ceiling plate 11B bonded together.
[0045] The structure of the discharging orifice structure and its characteristics to ink
have great influences on the recording characteristics of an ink jet recording head
such as the discharging direction of ink, the droplet amount of discharged ink, etc.,
and various investigations have been made in the prior art about the material to be
used for formation of the discharging orifice plate and its structure.
[0046] As the problem to be improved in the characteristics of the discharging orifice plate,
there is the problem that when a light pool of ink is formed around the discharging
orifice on the outer wall surface 40a of the discharging orifice plate, disturbance
is liable to occur in the discharging direction of ink as shown in Fig. 6B, whereby
no stable ink discharging can be obtained (see Fig. 6A) and no good recording can
be performed.
[0047] Moreover, when an ink attached film is formed on the whole surface around the discharging
orifice, scattering of ink during ink discharging (splash phenomenon) occurs, whereby
no stable recording can be performed, and the amount of the ink attached around the
discharging orifice is further increased to develop and enlarge the ink pool. If the
ink pool is excessively enlarged, ink discharging through the discharging orifice
may sometimes become impossible.
[0048] Accordingly, there has been known the method to prevent formation of such ink pool
as described above onto the outer wall surface of the discharging orifice by applying
water repellent treatment on the outer wall surface of the discharging orifice plate.
[0049] In the water repellent treatment of the outer wall surface, the treatment is required
to be performed so that the water repellent treatment may not be extended to the inner
surface of the discharging orifice which is demanded to be inkphillic.
[0050] The water repellent treatment of the outer surface of the discharging orifice in
the prior art has been performed by forming a thin layer of an ink repellent surface
treating agent on the surface of a transfer member and transferring the thin layer
onto the surface having the discharging orifice of the ink jet recording head.
[0051] Whereas, the method of the prior art have involved such problems that the treatment
working is cumbersome, and also that the water repellent agent may be progressed to
the inner portion of the discharging orifice, transfer cannot be sufficiently effected
or even water repellent surface can not be formed because of deterioration of the
transfer member.
[0052] As described above, ink jet recording head is generally equipped with fine ink discharging
orifice, ink channel and ink discharging energy generating element provided on a part
of the ink channel.
[0053] As the method for preparing such ink jet recording head, for example, there has been
known the method in which fine groove is formed by cutting, etching, etc. on a substrate
such as glass, metal, etc., and then the substrate having the groove formed thereon
is bonded to another appropriate substrate to form ink channel within the head.
[0054] In the case of having a plurality of ink channels, those channels are in most cases
communicated to a common liquid chamber and constituted so that the recording liquid
may be supplied smoothly and sufficiently into the liquid channels.
[0055] Whereas, for supplying sufficient amount of recording liquid corresponding to the
amount consumed by discharging of the liquid into the liquid channels, it is desirable
to have a common liquid chamber of a volume with sufficient room relative to the amount
consumed. However, with a common liquid chamber having a height virtually equal to
the height of the ink channel, flow resistance of the recording liquid cannot be made
substantially smaller, and therefore in spite of room in volume, no sufficient supply
of the recording liquid can be done in some cases.
[0056] Accordingly, it becomes the general constitution to make the height of the common
liquid chamber sufficiently larger than the height of the liquid channel.
[0057] However, in the method of forming fine grooves on a substrate such as glass or metal,
it is difficult to form a common liquid chamber having a sufficient height relative
to the height of ink channel.
[0058] It is also possible to make the height of the common chamber greater by increasing
the etching amount of the common liquid chamber by repeating etching for plural times,
but this method increases the steps and therefore cannot be said to respond sufficiently
to the demands for cost down or productivity.
[0059] Accordingly, it has been practiced to prepare separately the common liquid chamber
portion and bond the common liquid chamber portion to the end of the ink channel portion,
thereby forming a desired common liquid chamber.
[0060] According to this method, sufficient common liquid chamber volume can be obtained
easily and therefore it is preferable in aspect of performance of the ink jet head.
[0061] However, the method of bonding separately parts inherently has the problems of increase
of number of steps, lowering in productivity, and there remain still points to be
solved for accomplishing much cost down.
[0062] Also, in the case of using such method, generation of stress or positional slippage
accompanied with shrinkage by curing of the adhesive, leak of the recording liquid
due to incomplete sealing, flowing of the adhesive into the liquid channel or into
the common liquid chamber or clogging occurred in some cases.
[0063] In addition, as described above, the recording technique at the present time demands
higher precision and higher speed as a matter of course, and according to such demands,
the discharging orifices of the ink jet recording head became fine in dimension, higher
in orifice density became higher, and also became to have a plurality of orifice groups.
[0064] Particularly, for higher densification, the pitch between the recording dots becomes
narrower, and for making the fluid resistance through the ink path for higher speed,
there is the demand to expand the pitch between orifices.
[0065] For this purpose, by taking broad pitch between orifices and working the respective
discharging orifices obliquely to form the discharging directions of the recording
liquid so as to be convergent, it becomes possible to perform highly precise recording.
However, according to the working method of the prior art, it has been difficult to
perform working with delicate variances in the discharging angle for the respective
orifices.
[0066] Also, in a recording head having a plurality of the respective orifice rows for high
speed recording or color recording, if the distance between the respective orifice
rows is large, great memory size is required for adjusting the Dot signals between
the respective orifice rows, thereby resulting in the cost-up of the main printer.
SUMMARY OF THE INVENTION
[0067] It is an object of the present invention to overcome the defect in the prior art
and to provide the ink jet recording head which can be manufactured through simple
process and under little steps, and which is reliable and low in cost, and manufacturing
method thereof.
[0068] It is another object of the present invention to provide the orifice plate which
has orifices arranged in high density and with high accuracy, and the ink jet recording
head in which the relation between the orifice and ink path is accurately set and
manufacturing method thereof, in view of the above mentioned problem relating to the
orifice working and the connection of the orifice plate with the ceiling plate and
heater board.
[0069] It is still another object of the present invention to provide the ink jet recording
head in which the discharge performance is increased by working the orifice onto the
orifice plate comprised of plural kinds of materials.
[0070] It is still another object of the present invention to provide the ink jet recording
head which can obtain necessary ink droplet amount and discharge speed stably and
sufficiently upon recording.
[0071] It is still another object of the present invention to provide the discharge opening
plate and ink jet recording head in which the water repellent cover layer is provided
only at discharge opening surface and has adhesive layer for carrying out the adhering
operation with the main body of the head easily, and can be mass producted with high
yield, in view of the disadvantage in the ink jet recording head using the discharge
opening plate.
[0072] It is still another object of the present invention to provide the manufacturing
method of the ink jet recording head which has high accurate diameter of the ink discharge
opening and pitch, and which can be produced cheaply.
[0073] It is still another object of the present invention to provide the method for carrying
out the water repellent treatment only onto the outer wall surface of the discharge
opening of the plate effectively.
[0074] It is still another object of the present invention to provide the manufacturing
method for the ink jet recording head which can solve the above mentioned various
problem by forming the grooves for ink path by excimer laser after molding the ceiling
plate having the groove for common chamber.
[0075] It is still another object of the present invention to provide the ink jet recording
head and manufacturing method thereof which has the orifice plate of high density
and high accuracy, in which the discharge opening whose angle is changed in every
discharge opening and in every head can be easily formed on the orifice plate, and
in which relation between the orifice and the ink path are determined accurately.
[0076] Still another object is to provide a method for manufacturing an ink jet recording
head having an ink path communicated with a discharge opening, a discharge every generating
element disposed in said ink path, and a discharge opening plate provided with said
discharge opening and attached to an end surface of said ink path, the ink being discharged
from said discharge opening, characterized in that, said discharge opening is formed
by irradiating an excimer laser light to said discharge opening plate.
[0077] Still another object is to provide a method for manufacturing an ink jet recording
head having an ink path communicated with a discharge opening, a discharge energy
generating element disposed in said ink path, and a discharge opening plate provided
with said discharge opening and attached to an end surface of said ink path, the ink
being discharged from said discharge opening, characterized in that said discharge
opening plate is attached to said end surface of ink path prior to said discharge
opening is formed, and then an excimer laser light is irradiated to said discharge
opening plate attached to form said discharge opening.
[0078] Still another object is to provide a liquid discharge recording head, comprising,
a first base plate provided with a discharge energy generating element, a second base
plate formed by resin molding and is connected with said first base plate, said second
base plate having a groove for forming a liquid flow path corresponding to location
of said discharge energy generating element upon said connection, and being provided
with said liquid discharge opening for recording before said groove, said second base
plate having a member for forming said discharge opening whose thickness is selected
thinner at least a portion at which said discharge opening is formed.
[0079] Still another object is to provide a method for manufacturing a liquid jet recording
head made by connecting a first base plate provided with discharge energy generating
means and a second base plate for forming a liquid flow path for recording corresponding
to location of said discharge energy generating means, characterized in that, said
discharge opening is formed by irradiating an excimer laser light to a blank of second
base plate made of resin to which a plate member for forming a liquid discharge opening
for the recording is attached integrally.
[0080] Still another object is to provide a method for manufacturing an ink jet recording
head having an ink path communicated with a discharge opening, discharge energy generating
element disposed in said ink path for generating energy used for discharging the ink,
and a discharge opening forming member provided with said discharge opening and attached
to an open surface at which an opening communicated with said ink path is disposed,
the ink being discharged through said discharge opening to carry out the recording,
characterized in that, said discharge opening on said discharge opening forming member
is formed by irradiation of an excimer laser light, and said excimer laser entering
side upon said irradiation is attached to said open surface.
[0081] Still another object is to provide a method for manufacturing an ink jet recording
head having a base plate provided with a element generating discharge energy used
for discharging the ink, a ceiling plate having a recessed portion for forming an
ink flow path corresponding to disposed location of said discharge energy element
by being attached with said base plate, and a discharge opening forming member on
which a discharge opening communicated with said ink path, and discharges the ink
is formed, characterized in that, an excimer laser light is irradiated from said recessed
side to form said discharge opening, after said ceiling plate and discharge opening
forming member are connected integrally.
[0082] Still another object is to provide an ink jet recording head having a discharge opening
forming member provided with a discharge opening for dischargeing ink, an ink path
communicated with said discharge opening, and a discharge energy generating element
disposed on a part of said ink flow path to generate energy used for discharging the
ink, the ink being discharged to carry out recording, characterized in that, said
discharge opening forming member is formed by accumulating plural members of different
kind materials.
[0083] Still another object is to provide a discharge opening plate for an ink jet recording
head, comprising, a plate member, a water repellant cover layer provided on an upper
surface of said plate member, an adhesive layer provided on a lower surface of said
plate member, and a through hole for forming a discharge opening for discharging ink
therethrough being provided.
[0084] Still another object is to provide a method for manufacturing a discharge opening
plate for an ink jet recording head, comprising, a step for providing said water repellant
cover layer on an upper surface of plate member, a step for providing said adhesive
agent layer on a lower surface of plate member, a step for drilling a thorugh hole
on a plate member on which said both layers are provided for forming a discharge opening
for discharging the ink.
[0085] Still another object is to provide a method for manufacturing an ink jet recording
head, characterized in that, drilling a plate-like member made by accumulating a water
repellant layer, a base film and an adhesive agent layer sequencially, and adhering
said plate-like member to a surface on which an opening communicating with an ink
path of a head body.
[0086] Still another object is to provide a method for manufacturing an ink jet recording
head, characterized in that, drilling a plate-like member made by accumulating a water
repellant layer, a base film, an adhesive agent layer and a mold release film sequentially,
tearing said mold release film, and adhering said plate-like member whose mold release
film has been torn to a surface on which an opening communicating with an ink path
of a head body.
[0087] Still another object is to provide a method for manufacturing a discharge opening
plate having a through hole for forming a discharge opening, for an ink jet recording
head, comprising, a step for forming a metallic layer forming said discharge opening
plate at a surface of a base member on which a resin layer having configuration corresponding
to that of said through hole is arranged corresponding to arrangement of said through
hole, a step for making water repellant treatment to a surface of said metallic surface,
and a step for removing said resin layer from said surface of base member to form
said through hole.
[0088] Still another object is to provide a method for manufacturing an ink jet recording
head made by connecting a plate having grooves for forming ink paths provided corresponding
to each of plural ink discharge openings, and a base plate having a discharge energy
generating element disposed at a part of said ink paths, comprising, said grooves
of plate are formed by irradiating an excimer laser light.
[0089] Still another object is to provide a method for manufacturing an ink jet recording
head made by connecting a plate having grooves for forming ink paths provided corresponding
to each of plural discharge openings and a common liquid chamber for storing the ink
supplied to said ink paths, and a base member having a discharge energy generating
element disposed at a part of said ink paths, characterized in that, forming a base
member having said grooves for forming said common chamber by injection molding, working
said grooves forming said ink paths by irradiating an excimer laser light to said
base member.
[0090] Still another object is to provide a method for manufacturing an ink jet recording
head in which plural discharge openings are formed by irradiating excimer laser light,
characterized in that, at least one of entering angles of the laser light relative
to a surface of said discharge openings is differentiated from others.
BRIEF DESCRIPTION OF THE DRAWINGS
[0091]
Figs. 1A and 1B are views for explanating an assembly of conventional recording head;
Fig. 2 is an exploded schematic view for showing construction of ink jet recording
head;
Figs. 3A to 3C and Figs. 4A and 4B are views of construction of ink jet recording
head using discharge opening plate;
Fig. 5 is an exploded perspective view showing main portion of ink jet recording head
using discharge opening plate;
Figs. 6A and 6B are partial cross sections for explaining ink discharge condition;
Figs. 7A and 7B are respectively a exploded schematic view and a schematic view for
explaining cartridge including recording head of the present invention;
Figs. 8A and 8B are respectively plan view and partial enlarged view showing heater
board applicable for recording head of present embodiment;
Fig. 9 is a schematic view of apparatus according to one embodiment;
Fig. 10 is a perspective view showing relation between mask and orifice plate;
Fig. 11 is a schematic view of apparatus of another emobodiment;
Fig. 12 is a perspective view showing relation between mask and recording head of
Fig. 11;
Fig. 13 is a perspective view showing condition in which film having no orifice is
connected in manufacturing process of Fig. 11;
Fig. 14 is a perspective view showing state in which orifice has been formed by excimer
laser;
Fig. 15 is a cross section of orifice according to another embodiment;
Fig. 16 is a cross section of orifice according to conventional manufacturing method;
Fig. 17 is a cross section of main body of recording head forming cartridge;
Figs. 18 and 19 are schematic perspective views showing orifice manufacturing process
of recording head body of Fig. 17;
Figs. 20 and 21 are cross sections showing orifice manufacturing process according
to another embodiment;
Fig. 22 is a cross section showing one example of ink jet recording head;
Fig. 23 is a schematic construction view of orifice working device using excimer laser
light;
Fig. 24 is a schematic view for manufacturing orifice plate of one emobodiment is
manufactured;
Fig. 25 is a cross section of orifice and ink path of ink jet recording head of one
embodiment;
Fig. 26 is a schematic view in which orifice plate used for another embodiment is
formed;
Fig. 27 is a cross section showing orifice manufacturing process according to the
above embodiment;
Fig. 28 is a cross section of orifice and ink path of above embodiment;
Fig. 29 is a schematic construction view of orifice working device using excimer laser
light;
Fig. 30 is a schematic perspective view of main body having orifice of ink jet recording
head;
Fig. 31 is a cross section of main body having orifice of ink jet recording head;
Fig. 32 is a view showing one embodiment of discharge opening plate, in which Fig.
32A is a plan view and Fig. 32B is a cross section along line A-A of Fig. 32A.
Fig. 33 is a view showing construction of ink jet head manufactured by method of present
invention;
Figs. 34 and 35 are cross sections showing layer construction of plate-like member;
Fig. 36 is a view showing manufaturing process of plate-like member;
Fig. 37 is a front view of one embodiment of drilling device,
Figs. 38A to 38H are process views for explaining main processes of mehtod of the
present invention;
Fig. 39 is a perspective view showing blank of ceiling plate used in the present embodiment;
Fig. 40 is a view showing excimer laser device for forming orifice plate portion;
Figs. 41A and 41B are views for explaining ceiling plate manufacturing process according
to device of Fig. 40;
Fig. 42 is a schematic view of orifice manufacturing device using excimer laser light;
Figs. 43A and 43B are respectively a perspective view and a cross section of ceiling
plate with which orifice plate of ink jet recording head is made integral;
Fig. 44 is a perspective view of main body of ink jet recording head made by connecting
heater board and ceiling plate of Fig. 43;
Figs. 45A and 45B are respectively perspective view and cross section of ceiling plate
with which orifice plate according to another embodiment is made integral;
Fig. 46 is a cross section of one example of orifice;
Fig. 47 is a perspective view of resin plate which has not been manufactured;
Fig. 48 is a perspective view of ceiling plate which has been manufactured by present
embodiment;
Fig. 49 is a view for explaining removing work by excimer laser via mask;
Fig. 50 is a schematic view of groove obtained work of Fig. 49;
Fig. 51 is a schematic perspective view of main body of ink jet recording head obtained
by using ceiling plate of embodiment;
Fig. 52 is a schematic view of apparatus for manufacturing ink jet recording head
of present invention;
Fig. 53 is a perspective view showing mask and discharge opening forming member of
Fig. 52;
Fig. 54 is a schematic view of manufacturing device for discharge opening forming
member suitable for carrying out manufacturing method of present invention;
Fig. 55 is a perspective view showing mask and discharge opening forming member of
Fig. 54;
Fig. 56 is a schematic view illustrating by method of present invention;
Fig. 57 is a perspective view of ink jet recording head of another embodiment of the
present invention;
Figs. 58A and 58B are respectively a schematic view illustrating device for entering
laser beam to form discharge opening;
Fig. 59 is a schematic explanation view for showing partial construction of ink jet
recording head manufactured by present invention;
Figs. 60 and 61 are views for explaining connected or assembled state of recording
head body; and
Fig. 62 is a perspective view showing one embodiment of ink jet printer constructed
by using cartridge as shown in Fig. 7.
PREFERERRED EMBODIMENT OF THE INVENTION
[0092] The present invention is described in detail by referring to examples.
[0093] Figs. 7A and 7B show respectively schematic disassembled view and assembled view
of a ink jet recording head according to an example of the present invention in which
an ink housing portion which is an ink feeding source is made integral to give a disposable
type.
[0094] In Fig. 7A, numeral 100 is a heater board comprising an electricity heat convertor
(discharging heater) and a wiring of A1, etc. for feeding power thereto formed by
film forming technique on a Si substrate, which corresponds to the first substrate
1 in Fig. 9. Its detailed constitution is described below by referring to Fig. 8.
200 is a wiring substrate corresponding to the heater board 100, and the corresponding
wiring is connected by, for example, wire bonding.
[0095] 400 is a ceiling plate provided with a partition wall, a common liquid chamber for
limiting the ink flow channel, which corresponds to the second substrate 8 in Fig.
1 and in this embodiment is comprises a resin material having integrally an orifice
plate portion. The detailed one embodiment of this ceiling plate 400 is described
below by referring to Figs. 39 to 41.
[0096] 300 is a support made of, for example, a metal, 500 is a pressing spring, and by
engaging the both under the state with the heater board 100 and the ceiling plate
400 sandwiched therebetween, the heater board 100 and the ceiling 400 are pressure
fixed by the urging force of the pressing spring 500. One embodiment is described
by referring to Figs. 62 and 63. The support 300 as well as the wiring substrate 200
can be provided by plastering, etc., and also can be made to have the mounting standard
onto the carriage for performing scanning of the head. Also, the support 300 also
functions as the member which cools the heater board 100 by release of the heat generated
with driving.
[0097] 600 is a feeding tank, which receives ink feed from the ink reservoir portion forming
the ink feeding source, and functions as a subtank leading the ink to the common liquid
chamber formed by bonding of the heater board 100 and the ceiling plate 400. 700 is
a filter arranged at a site in the feeding tank 600 near the ink feeding inlet to
the common liquid chamber, and 800 is a lid member of the feeding tank 600.
[0098] 900 is an absorber for impregnation of ink, and is arranged within the cartridge
main body 1000. 1200 is a feeding inlet for feeding ink to the unit comprising the
respective portions 100 - 800 as described above, and by injecting ink through the
feeding inlet 1200 in the step prior to arrangement of said unit to the portion 1010
of the cartridge main body 1000, ink can be impregnated into the absorber 900.
[0099] 1100 is a lid member of the cartridge main body, and 1400 is an air communicating
opening provided at the lid member for communication to the air. 1300 is a liquid
repellant material arranged inwardly of the air communicating opening 1400 by which
the ink leak through the air communicating opening 1400 can be prevented.
[0100] On completion of ink filling through the feeding inlet 1200, the unit comprising
the respective portions 100 - 800 is arranged by registration at the portion 1010.
Registration or fixing at this time can be effected by, for example, fitting the projection
1012 provided on the cartridge main body 1000 with the hole 312 provided on the support
300 corresponding thereto, whereby the cartridge shown in Fig. 7B is completed.
[0101] The ink is fed into the feeding tank 600 from the cartridge inner portion through
the feeding inlet 1200, the hole 320 provided at the support 300 and the introducing
inlet provided on the back side in Fig. 7A of the feeding tank 600, and after passing
through the inner portion thereof, flows from the discharging outlet into the common
liquid chamber through an appropriate feeding pipe and the ink introducing inlet 420
of the ceiling plate 400. At the connecting portion for ink communication as described
above, for example, packing of silicone rubber, butyl rubber, etc. is provided, whereby
sealing is effected to ensure the ink feeding flow channel.
[0102] Figs. 8A and 8B are a plan view of the heater board 100 according to this example
and its partial enlarged view.
[0103] In Fig. 8A, 101 is the heater board substrate according to this embodiment, and 103
the discharging heater portion. 104 is a terminal, which is bonded by wire bonding
to the outside. 102 is a temperature sensor, which is formed at the discharging heater
portion 3, etc. according to the same film forming process as for the discharging
heater portion 103, etc. Fig. 8B is an enlarged view of the portion B including the
sensor 102 in Fig. 8A, 105 and 106 are respectively discharging heater and wiring.
108 is a heater for heating the head.
[0104] The sensor 102 is formed according to the same film forming process as information
of semiconductors similarly as other portions, and therefore extremely high in precision,
and can be formed of a material varying in electroconductivity depending on temperature
such as aluminum, titanium, tantalum, tantalum pentoxide, niobium, etc. which is the
constituent material of other portions. For example, among them, titanium is a material
which can be arranged between the both for enhancing adhesiveness between the heat-generating
resistance layer constitutes the electricity-heat converting element and the electrode,
and tantalum is a material which can be arranged at the upper portion for enhancing
the cavitation resistance of the protective layer on the heat-generating resistant
layer. Also, for making variance in the process smaller, line width is made bold,
and for making the influence of wiring resistance, etc. smaller, a zig-zag shape is
formed to make the resistance higher.
[0105] In the recording head shown in Figs. 7A and 7B, the orifice plate should desirably
have a thickness of about 10 to 50 µm, and also in view of the cost of material and
ink resistance as the material of the orifice plate, film materials of thermoplastic
resins, such as polyether ketone, polyimide, polyether sulfone, etc. may be included.
In this example, a film of a polyether ether ketone (PEEK) with a thickness of 25
µm is used.
[0106] When forming an orifice plate, first the above film material is cut into a size necessary
for orifice plate. Next, by use of an excimer laser of KrF emitting UV-ray of 248
nm wavelength, working of orifice is performed by means of a device shown in Fig.
9.
[0107] The excimer laser is a laser capable of oscillating UV-ray and has such advantages
as high strength, good monochromaticity, directional characteristic, capability of
short pulse oscillaton, capability of making energy density very great by focusing
with a lens.
[0108] Exicimer laser is a device capable of oscillating UV-ray of short pulses (15 - 35
ns)by discharging excitation of a gaseous mixture of rare gas and halogen, and Kr-F,
Xe-Cl, Ar-F laser are frequently used. The oscillation energy of these may be some
100 mJ/pulse, and the pulse repetition frequency 30 to 100 Hz.
[0109] When the short pulse UV-ray of high luminance such as the excimer laser is irradiated
on a polymer resin surface, there occurs the Ablative Photodecomposition (APD) process
where the irradiated portion is decomposed and scattered momentarily with accompaniment
of plasma emission and impact sound, by which process working of the polymer resin
is rendered possible.
[0110] Thus, when working precision excimer laser is compared with that with other lasers,
for example, if a polyimide (PI) film is irradiated with KrF laser as an excimer laser
and other YAG laser and CO₂ laser, since the wavelength absorbing light of PI is in
the UV region, beautiful holes can be opened by KrF laser, but the edge surface is
roughened by YAG laser which is not in the UV region although holes may be opened,
while craters are formed around the hole by CO₂ laser which is IR ray.
[0111] Also, metals such as SUS, etc., opaque ceramics, Si, etc. are not influenced by irradiation
of excimer laser in an atmosphere of the air and hence can be used as the masking
material in working by excimer laser.
[0112] Fig. 9 is a schematic illustration of a device for performing working orifice by
use of such excimer laser. In Fig. 9, 210 is an excimer laser, 211 is a lens for focusing
laser beam 212 emitted from the excimer laser 210, 209 is a mask arranged between
the excimer laser 210 and the orifice plate, and 240 is an orifice plate on which
orifices are to be formed.
[0113] Fig. 10 is a perspective view showing the details of the mask 209 and the orifice
plate 240. On the mask 209 are provided transparent portions 291 corresponding to
the sites where orifices on the orifice plate 240 are to be worked so that laser beam
212 may be transmitted therethrough. Thus, by providing a pattern necessary for orifices
on the mask 209, this pattern can be worked into the film for orifice plate.
[0114] As shown in Fig. 10, the number of the orifices is plural, but this is shown schematically
and practically in this example a mask having orifices of 360 DPI φ 33 µm linearly
juxtaposed is used. In this constitution, orifices are formed by irradiation of laser
beam 212 through the mask 209 on the plate 240. As the mask material, it should preferably
receive no influence of the heat by laser irradiation, and, for example, a material
with small coefficient of thermal expansion, such as a metal material of Be-Cu, etc,
can be used.
[0115] The orifice on the orifice plate prepared according to the method as described above
is free from abnomal deformation at the peripheral portion of the orifice as in working
by carbon dioxide laser and YAG laser, and a circular form similar to the mask is
worked beautifully from the surface to the back of the film.
[0116] The results of comparison between the design value and the dimension in the orifice
plate after preparation according to the method as described above are shown in Table
1.
Table 1
|
Design value (µm) |
Dimension after laser working (µm) |
Error (µm) |
Pitch variance |
70.5 |
70.4 |
- 0.1 |
Hole diameter |
34.0 |
33.9 |
- 0.1 |
[0117] As is also apparent from comparison in this Table 1, the orifice working with excimer
laser has sufficient precision for further improvement of the performance of the ink
jet recording head, and also has a specific feature that it can be produced simply.
[0118] In the following, a more effective example of the present invention is described.
[0119] Fig. 11 and Fig. 12 are respectively a schematic view and a perspective view representing
the details of the mask and the orifice of the orifice working device.
[0120] In this example, first, a glass material applied with grooving as the ceiling plate
400 and a heater board 100 having energy generating elements and wirings therefor,
etc. provided on a Si wafer are bonded together, and then the bonded surface was subjected
to ozone washing of the orifice plate 40, the ceiling plate 400 and the heater board
100, followed by coating of a silane coupling agent. The coating method is performed
by transfer from a silane coupling agent A-187 (from Nippon Unicar K.K) spin coated
on a Si rubber of φ 100, t=0.6.
[0121] Next, a dry film (Tokyo Ohka K.K., SE-320) as the material of the orifice plate 40
after peel off of the protective film, polyether on one side is heated to about 40
- 80°C. At this time, the ceiling plate 400 and the heater board 100 integrally combined
are also heated at the same time. This heating is performed by use of a hot plate
or a clean oven in this example.
[0122] After the dry film is sufficiently heated, the dry film surface of the film and the
ceiling plate-heater board are pushed against each other under a pressure of 2 to
10 kg/cm² for 1 to 10 seconds to be bonded together. Next, the composite is cooled
gradually to room temperature (about 25°C), followed by separation of the film from
the ceiling-heater board. At this time, the dry film which becomes the orifice plate
is separated from the other protective film of Mylar film to be bonded to the ceiling-heater
board to become the state shown in Fig. 13. Next, UV-ray is irradiated on the bonded
dry film surface to effect curing of the film, and the recording head (ceiling plate-heater
board orifice plate) is fixed at a predetermined position comprising the constitution
shown in Fig. 11, followed by registration of the recording head, the excimer laser
and the mask. This registration is corresponded by making the stand 207 for filing
the recording head movable system in this example.
[0123] After completion of registration, excimer laser light is irradiated on the orifice
plate 240 through the mask 209 to effect working of the orifice 241. The state of
the recording head after such wording is shown in Fig. 14.
[0124] According to the method as described above, it is not necessary to perform bonding
by registration with high precision between the orifice plate having fine orifices
and the ceiling-heater board, whereby the preparation steps of the ink jet recording
head become simple.
[0125] Next, an example for making the orifice shape a more preferable shape by working
with excimer laser is shown.
[0126] As shown in Fig. 15, the orifice shape of the ink jet recording head in this example
has been deemed to have desirably a shape which is narrower at the tip as nearer from
the ink channel 402 toward the orifice 241. However, because it can be realized with
difficulty in the preparation method of the prior art, most of its shape have been
columnar as shown in Fig. 16.
[0127] Whereas, by use of excimer laser, and utilizing the specific feature that the shape
of the hole is varied by changing the position of the focus by moving gradually the
focusing lens during irradiation in working only of the orifice plate, also an orifice
shape as shown in Fig. 15 can be produced.
[0128] Fig. 17 is a sectional view of an ink liquid channel of the ink jet recording head
according to an another example of the present invention. In Fig. 17, 40a is one plate
of the orifice plates comprising two kinds of materials, and 40b is the other orifice
plate. In this example, as the material for the plate 40a, a PI film with a thickness
of about 20 µm is used, and as the material for the plate 40b, a dry film with a thickness
of about 20µm (SE-320, manufactured by Tokyo Ohka K.K.) for bonding the PI film 40a
to the opening surface at which the openings of ink liquid channels are arranged.
[0129] Also, in this example, the PI film 40a is bonded to the dry film 40b before bonding
to the opening surface of the ink liquid channels, but of course the PI film 40a may
be also bonded after bonding of the dry film 40b to the opening surface. By such bonding,
the main recording head becomes the state as shown in Fig. 18.
[0130] Next, orifices are worked by laser beam on the main recording head bonded with the
orifice plate. In this example, an excimer laser is used. As shown in Fig. 19, by
first using a mask 209 of SUS having a shape 291 of orifice to effect registration
between the opening of the ink liquid channel and the orifice shape 291 of the mask
209, an excimer laser beam is irradiated on the mask 209 for several seconds. The
orifice places 40a, 40b at the portions irradiated with the excimer laser are removed
to form the orifices 241. At this time, since the range removed is varied depending
on the material of the film orifices 241 with the shapes shown in Fig. 17 are obtained.
[0131] The shape which becomes smaller in diameter toward the tip end shown in Fig. 17 has
the effect of increased discharging speed and also the discharging direction which
is made constant, leading to improvement of recorded image quality.
[0132] Fig. 20 and Fig. 21 concern other examples of the present invention, showing similarly
sectional views as in Fig. 17. The same shape of the ink liquid channel 401 and the
same dry film for the material of the orifice plate 40b as in Fig. 17 are used. Next,
by applying etching on SUS, etc., the orifice and the metal material 40a' formed are
bonded to the opening of the ink liquid channel with registration. This state is shown
in Fig. 20.
[0133] Next, the orifice is worked by irradiation of the excimer laser beam similarly as
in the first example. This state is shown in Fig. 21. As can be seen from Fig. 21,
in this example, there is obtained the effect that no mask for laser working is separately
prepared, because the SUS material 40a' also functioning as the mask becomes the orifice
plate as such.
[0134] Further, other examples are described. The shape of the ink liquid channel and the
orifice plate 40b are the same as in the example as described above, and as the material
for the orifice plate 40a, films of Myler, Tedlar (registered brand), etc. are used.
The film 40a is previously bonded to the plate 40b, and then bonded to the opening
surface of the liquid channel. Thereafter, the orifice is worked with an excimer laser
beam. The recording head obtained according to this Example has water repellency at
the discharging orifice surface and the orifice plate, and therefore no unnecessary
ink pooling or dew formation occurs at the discharging orifice surface, whereby stable
discharging without influences from these is rendered possible.
[0135] As the orifice of recording head according to such embodiment, it is desirable to
obtain the tapered configuration in which diameter decreases from the ink liquid path
side toward the discharge opening side, not the tapered configuration in which diameter
decreases from the discharge opening side toward the ink liquid side, as shown in
Fig. 22.
[0136] Fig. 23 shows the manner in which orifice working is performed by excimer laser beam
on the orifice plate made of a resin film according to another embodiment of the present
invention, and the same elements as those shown in Fig. 29 are attached with the same
symbols. In Fig. 23, 210 is a laser oscillating device for oscillating KrF excimer
laser beam, 212 a pulse laser beam with a wavelength of 248 mm and a pulse width of
about 15 nsec oscillated from the laser oscillating device 211, 211 a synthetic quartz
lens for converging the laser beam 212, 209 a projection mask having aluminum capable
of shielding the laser beam 212 vapor deposided thereon, on which a plurality of holes
of 133 µm in diameter are arranged at a pitch of 212 µm to constitute an orifice pattern.
40 is an orifice plate member, which comprises a film of polyether sulfone (PES) having
a thickness of 4µm coated with a 6 µm thick tacky layer, and further plastered with
a 25 µm thick Mylar.
[0137] Fig. 24 is an enlarged sectional view of the orifice plate member 40 shown in Fig.
23, and in Fig. 24, 12B is a PES film forming the orifice plate, 13B a tacky layer
as the adhesive, and 178 a Mylar. In this case, on the emitting side of the laser
beam on the PES film 12B which becomes the orifice plate by irradiation of the laser
beam 212 through the mask 209, orifices of 3 µm are formed at a pitch of 70 µm. After
the orifice plate member 40 is irradiated with laser beam to be made into the state
shown in Fig. 24, the orifice plate 12B obtained by peel-off of the Mylar 17B is bonded
to the opened face of the ink channel to complete the main ink jet recording head.
[0138] Fig. 25 is a sectional view of the main recording head thus obtained. As can be clearly
seen by comparison between Fig. 25 and the sectional view of the main recording head
of the prior art shown in Fig. 31, since the side of the orifice plate on which laser
beam is irradiated is bonded to the opened face of the ink channel, the shape obtained
by this example becomes tapered, being widened in the direction opposite to the discharging
direction. With such shape, the discharging speed and the ink amount discharged are
increased stably to give the result that quality of the recorded image is improved.
[0139] Next, an example by use of a dry film (Tokyo Ohka, SE320) as the material of the
orifice plate is described by referring to Fig. 26 to Fig. 28. The laser beam, the
optical system and the projection mask are the same as in the example as described
above.
[0140] Fig. 26 is an enlarged views of the portion where the laser beam 212 is incident
on the film, and in Fig. 26, 18B is a dry film forming the orifice plate, 19B a protective
film comprising a polyether and 20B a Mylar.
[0141] In this constitution, after the laser beam 212 is first irradiated, the orifice plate
of the dry film obtained by peel-off of the protective film 19B is bonded to the opened
face of the ink channel (Fig. 27).
[0142] Next, the Mylar is peeled off to form the state shown in Figs 28, and UV-ray is irradiated
on the orifice plate 18B of the bonded dry film from the discharging direction side
to effect photocuring, thereby completing the main ink jet recording head. Also according
to this example, a shape with the taper of the orifice being widened in the direction
opposite to the ink discharging direction is obtained.
[0143] Figs. 30 and 31 show detail of a main body 205 of the ink jet recording head in which
a orifice is formed by causing the laser beam 212 oscilated from laser device 210
of Fig. 29 to enter from an orifice forming surface side of the body 205, among which
Fig. 30 is an enlarged view of the head body (each members are shown so as to the
separated slightly for simplicity), Fig. 31 is a cross section thereof.
[0144] In Figs. 30 and 31, 207 is a ceiling plate provided with grooves for forming the
groove discharging the ink, 208 is a base plate provided with patterning of the discharge
energy generating element, 209 is an opening communicated with the ink path, 10B is
an orifice plate made of resin film, 41 is an orifice formed on the orifice plate
10B. 13B is an adhesive agent for adhering the orifice plate 10B to an opened surface
at which the opening of ink path, 401 is an ink path, 101A is an electro-mechanical
converting element as discharge energy generating element.
[0145] As shown in Fig. 31, the orifice work according to mere excimer laser, orifice portion
may have tapered configuration whose discharge opening side is flared.
[0146] On the contrary, according to the above embodiment, the orifice may have convergent
configuration, it is possible to obtain the amount of ink liquid droplet necessary
for recording and the discharge speed, to recording image in high quality can be realized.
[0147] In the following, an another example of the present invention is described in detail.
[0148] In the method of the present invention, first as shown in Fig. 32B, on one surface
of a plate member 302 capable of forming a discharging orifice plate, a liquid repellent
(ink repellent) coating layer 303 and an adhesive layer 304 are provided. As the plate
member 302, one comprising a resin, a metal, etc. can be utilized.
[0149] As the resin to be used for the plate member in the case of using a thermosetting
resin for the adhesive layer 304, it is preferable to use a resin having high heat
resistance which will not give rise to deformation, etc. during heat curing of the
adhesive layer 304, such as polyimide, polyether sulfone, polysulfone, polyester,
acrylic resin, phenol resin, urea resin, melamine resin, epoxy resin, silicone resin,
etc.
[0150] Also, the resin plate member may be also improved in strength and other characteristics
by addition of various additives or fillers into the resin. When a plate member made
of a metal is used, for example, a plate member comprising stainless steel, nickel,
gold, silver, platinum, etc. can be utilized.
[0151] Said plate member should be conveniently thin in its thickness for the purpose of
inhibiting flash or residue during formation of thru-holes for formation of discharging
outlets as described below to the extent which gives no bad influence on ink discharging,
or for the purpose of performing continuous perforation but for the balance with the
strength, it should desirably have a thickness within the range from 5 to 100 µm.
[0152] The liquid repellent coating layer 303 may be formed of any material provided that
it has sufficient adhesion characteristic with the plate member 302, and also has
liquid repellency to the extent that it repells aqueous ink to be used for recording
and the ink does not remain as droplet by attachment on the surface and, for example,
can be formed of a material suitably selected from the materials known as conventional
liquid repellent treating agents. Also, during formation of such coating layer, the
layer thickness or other forming conditions may be suitably set so that good liquid
repellent characteristic at the discharging outlet surface may be obtained.
[0153] The adhesive layer 304 may be formed of a material suitably selected which can give
good bonded sate between the discharging orifice plate and the main recording head
portion and, for example, an epoxy type adhesive subjected to B staging by the heating
treatment under the conditions of 100 °C - 120 °C for 30 to 60 minutes, etc. can be
utilized, and provided to a layer thickness of about 1 to 5 µm.
[0154] For formation of the liquid repellent coating layer 303 and the adhesive layer 304,
for example, there can be utilized, for example, the dipping method, the coating method,
the printing method, the spraying method, the method of transferring the liquid repellent
coating layer or the adhesive layer to a predetermined portion, etc.
[0155] Next, a thru-hole 301 is opened at a predetermined portion of the plate member 302
having the liquid repellent coating layer 303 and the adhesive layer 304 provided
thereon as described above.
[0156] For formation of the thru-hole 301, the press working method, the electron beam working
method, the laser beam working method, the liquid jet working method, etc. can be
utilized. By combining the plate member 302 with the above-mentioned constitution
with these methods, perforation working of high precision perforation working can
be done at high speed and simply.
[0157] The discharging orifice plate formed as described above is tentatively bonded by
superposing with registration on a predetermined position of the main recording head
portion having flow channel walls, etc. with the constitution as shown in Fig. 3 and
Fig. 4 provided on a substrate through, for example, the adhesive layer 304 subjected
to B staging, then subjected to the heating treatment under the condition of 150 to
200 °C for 30 to 120 minutes to completely cure the adhesive layer 304 subjected to
B staging to effect bonding these, whereby the recording head of the present invention
can be obtained.
Example a
[0158] On one surface of a polyimide film (plate material) with a thickness of 30 µm, an
epoxy type adhesive comprising a mixture of various components shown below was coated
according to the spin coating method under various conditions shown below, further
subjected to the heating treatment under the conditions of 100 °C to 120 °C, and 30
to 60 minutes, followed by drying and solification to effect B staging, to give a
number of plate materials attached with adhesive layers. The layer thickness of the
adhesive layer after B staging was found to be 1 to 5 µm.
Adhesive layer composition: |
(1) Mixture of Epikote 1004 (trade name) and methyl ethyl ketone formulated at 2 :
1 (weight ratio) |
100 parts by weight |
(2) Mixture of dicyandiamide and dimethylformamide formulated at 1 : 4 (weight ratio) |
3 parts by weight |
(3) N,N-dimethylbenzylamide |
0.2 parts by weight |
Spin coating conditions: |
rotational number: |
500 - 1000 rpm |
time: |
5 - 10 sec. |
[0159] Next, on the surface (back surface) opposed to the surface of the plate material
attached with the adhesive layer where the adhesive layer is provided, a solution
prepared by adding a fluorine silicon coating agent KP - 801 (trade name, manufactured
by Shinetsu Kagaku Kogyo) to 0.07 % by weight into Difreon S-3 (trade name, manufactured
by Daikin Kogyo) was spin coated under the various conditions shown below, and then
subjected to the heating treatment of 80 °C to 120 °C form a liquid repellent coating
layer of 1 µm or less.
Spin coating conditions: |
rotational number: |
2500 - 3000 rpm |
time: |
20 - 30 sec. |
[0160] Next, on each of the plate materials obtained by the above operations, 48 thru-holes
(diameter 30 ± 2 µm, pitch 70.6 ± 2 µm) were formed according to the continuous perforation
working method by a press at predetermined positions to obtain a discharging orifice
plate.
[0161] When the states of the liquid repellent coating layer and the adhesive layer in the
discharging orifice plate obtained were examined, both were found to be formed uniformly
with predetermined layer thicknesses only on the surface of the plate, with only the
polyimide film being exposed within the thru-holes for forming the discharging orifices.
[0162] The thus obtained discharging orifice plate was tentatively adhered with registration
at the predetermined positions shown respectively on the main recording head portion
having flow channel walls, etc. on a substrate with the constitution shown in Fig.
3 and Fig. 4 through its adhesive layer, and then the adhesive layer of the discharging
orifice plate was completely cured by the heating treatment at 150 °C to 200 °C for
30 to 120 minutes, to complete a recording head.
[0163] As the main recording head portion to be used in this Example, one conventionally
used in this field was used. Also, the ink discharging energy generating member, the
electrical system for applying discharging signals on said generating member, etc.
were formed by utilizing the materials conventionally used in this field.
Example b
[0164] A discharging orifice plate was obtained in the same manner as in Example a except
for using a stainless steel plate with a thickness of 50 µm as the plate material,
and forming perforation of thru-holes by the continuous perforation working with electron
beam.
[0165] The discharging orifice plate obtained was found to have good quality similarly as
in Example a.
[0166] These discharging orifice plates were tentatively adhered with registration on the
predetermined positions shown on the main recording head portion with the construction
shown in Fig. 4 (formed by utilizing materials conventionally used in this field),
and then adhesive layer of the discharging orifice plate was completely cured by the
heating treatment at 150 °C to 200 °C, for 30 minutes to 120 minutes, to complete
a recording head.
Comparative example a
[0167] On a polyimide film with a thickness of 30 µm, thru-holes were provided with the
same sizes and the arrangements as in Example 1 according to the continuous performation
working method by a press.
[0168] On the other hand, a solution obtained by mixing a two-liquid epoxy adhesive (trade
name: HP-2R/2H, manufactured by Canon Chemical) mixed into methyl ethyl ketone at
a ratio of 0.5 % by weight was uniformly spin coated on a 0.5 mm silicone rubber under
the conditions shown below.
Spin coating conditions: |
rotational number: |
500 - 1000 rpm |
time: |
5 - 10 sec. |
[0169] Next, the bonded surface of each discharging rifice plate of the main recording head
portion used in Example a (with the constitution shown in Fig. 3 and Fig. 4) is pressed
under a load of about 2 kg/cm² against the two-liquid mixed epoxy resin adhesive layer
on the silicone rubber obtained by the above operation, and then the silicon rubber
was peeled off to have the adhesive layer onto the main recording head.
[0170] The discharging orifice plate previously obtained was tentatively adhered with registration
onto the transfer adhesive layer thus obtained, and then subjected to the heating
treatment at 60 °C to 100 °C for 30 minutes to 60 minutes to cure the adhesive.
[0171] Next, the fluorine silicone coating agent solution used in Example a was spin coated
uniformly on a silicone rubber with a thickness of 0.5 mm under the conditions shown
below.
Spin coating conditions: |
rotational number: |
2500 - 3000 rpm |
time: |
20 - 30 sec. |
[0172] After the whole discharging orifice surface bonded to the main recording head previously
obtained was pressed under a load of 2 kg/cm² against the fluorine silicone coating
agent layer on the silicon rubber thus obtained, the silicone rubber was peeled off
to have the fluorine silicone coating agent layer transferred onto the discharging
orifice plate surface of the main recording head, followed further by curing by heating
at 80 °C - 120 °C, to complete a recording head.
Comparative example b
[0173] A recording head was prepared in the same manner as in Comparative example a except
for using a stainless steel plate with a thickness of 50 µm as the plate material,
and the same one as used in Example b as the main recording head.
[0174] When tests were conducted for yields in the bonding steps and the liquid repellent
treatment steps of the discharging orifice plates in the recording heads obtained
in the respective Examples and Comparative examples, and initial printing and prolonged
printing in recording operations by use of the recording heads obtained, the results
shown in Table 2 were obtained.
[0175] In the respective tests, each 50 of recording heads prepared in respective examples
were used.
Table 2
|
Example a |
Example b |
Comparative example a |
Comparative example b |
Discharging plate bonding |
100% |
100% |
88% |
94% |
Ink repellent treatment |
|
|
91% |
89% |
Initial printing |
100% |
100% |
95% |
95% |
Prolonged printing |
100% |
100% |
95% |
98% |
[0176] In the following, another examples of the present invention are described by referring
to the drawings.
[0177] First, as shown in Fig. 33, the ink jet liquid has grooves which become ink channels
505 and ink liquid chamber 506 on an appropriate substrate 501 such as glass, metal,
plastic, etc., and further has a energy generating member 504 for generating energy
to be utilized for discharging ink such as heat energy, etc. on the lower side of
another substrate 502 along the groove formed along the substrate 501, followed by
bonding of the substrate 501 and the substrate 502 to prepare a main head 507. Subsequently,
the discharging orifice plate 503 which is a plate body of a multilayer structure
applied with high precision hole opening by press working is adhered to the surface
of the main head 507 where openings communicated to the ink channels 505 are formed.
[0178] Next, the multilayer structure of the discharging plate 503 as described above is
described by referring to Fig. 34 and Fig. 35.
[0179] Referring first to Fig. 34, this case is formed of a plate body 520A comprising the
three layers having an ink repellent layer 531, a base film 532 and an adhesive layer
533 successively laminated, and after the plate body 520A is subjected to hole opening
by press working, it is adhered as the discharging orifice plate 503 with the adhesive
layer 533 onto the main head 507.
[0180] Referring to Fig. 35, this case is formed of a plate body 530 comprising four layers
having an ink repellent layer 531, a base film 532, an adhesive layer 533 and a release
film 534 successively formed, and after the plate body 530 is subjected to hole opening
by press working, it is adhered as the discharging orifice plate 503 by peeling the
release film 534 with the adhesive layer 533 onto the main head 507.
[0181] As the base film 532 laminated in the plate bodies 520A, 530, it is desirable to
use a plastic film excellent in ink resistance, for example, non-stretched film such
as polyether ether ketone (PEEK), polyether sulfone (PES), polysulfone (PSF), polyethylene
terephthalate (PET), polyimide, etc. This is intended to inhibit the shrinkage to
minimum during heating of the plate bodies 520A, 530 at the time of curing of the
adhesive, and in this example, a polyether ether ketone (PEEK) with a plate thickness
of 25 µ is employed. The nonstretched film of 25 µ polyether ether ketone (PEEK) is
sufficiently satisfactory in precision with a heat shrinkage of 0.1 % or less after
held at 150 °C for 4 hours.
[0182] Subsequently, the preparation steps of the plate body with the multilayer structure
are described by referring to Fig. 36 by taking an example of the plate body 530 with
the four layer structure as described above.
[0183] The preparation steps of the plate body 530 comprise the 7 steps of the film washing
step 601, the ink repellent treatment agent coating step 602, the drying step 603,
the surface modification step 604, the adhesive coating step 605, the drying step
606 and the release film molding step 607.
[0184] In the following, the respective steps are described in detail.
[0185] The points of the present embodiment are the ink repellent treatment and the adhesive
coating, and therefore other steps are omitted.
[0186] First, concerning the ink repellent treatment agent coating step 602, it has been
practiced in the prior art to effect the water repellent treatment after hole working,
whereby there may be occurred clogging of hole with the ink repellent treatment agent.
This problem can be improved by applying this step to the base film 532. As the ink
repellent treatment agent, fluorine type or silicon type agents such as Fluorocoat
of Asahi Glass, LF-40 of Soken Kagaku, DEFENSA-7702 (trade name) of Dainippon Ink
Kagaku, etc. may be employed. In this example, DEFENSA-7702 is coated by a roll coater.
[0187] Next, concerning the adhesive coating step 605, the base film 532 as described above
is excellent in chemical resistance and therefore adhesion strength between the adhesive
and the base film 532 cannot but become weak. For improvement of the adhesion strength
between the adhesive and the base film 532, surface modification of the base film
532 is effected in the surface modification step 604.
[0188] As the means for surface modification, the plasma treatment, the uv/O₃ treatment,
etc. are effective. As an example of the present invention, the uv/O₃ treatment method
was employed. Evaluation of surface modification was performed in terms of contact
angle. By irradiation of a light of 2537 Å at 20 mw/cm² for 5 minutes, the initial
contact angle 36° could be improved to 31 with polyether ether ketone (PEEK). As the
next step, the step of coating an adhesive onto the base film 532 with the modified
surface is performed, and the characteristics demanded for the adhesive may include
the following items.
1. It is initially smooth without stickiness.
2. It becomes sticky with light, heat etc. when bonded to the main head.
3. It has firm adhesive force after the main adhesion.
4. It is excellent in ink resistance.
[0189] As the adhesive satisfying these conditions, epoxy type uv curable adhesives, acrylic
uv curable adhesive, etc. may be included. In this example, a stock solution of a
dry film is coated by roll coating and vacuum dried.
[0190] Finally, the release film plastering step 607 is not required if the above characteristic
1 of the adhesive layer 533 being initially smooth is complete, but practically more
or less stickiness may sometimes remain, and therefore in view of easiness during
the press working in the later step, a release film 534 may be laminated. As the release
paper, polyethylene (PE), polyvinyl fluoride (PVF), etc. are suitable.
[0191] By use of the plate body 530 obtained according to the steps as described above,
the item of clogging of holes with adhesive, ink repellent treatment agent which is
the problem of the prior art has been solved. In preparing the plate body 520A with
the three layer structure shown in Fig. 36, it can be accomplished by deleting the
release film plastering step 607 in Fig. 36.
[0192] Subsequently, hole opening for forming ink discharging orifices is performed by applying
press working on the plate body 530 obtained according to the steps as described above.
[0193] In this case, the plate body 530 is mounted on the delivery table 604 and the die
655 of a press hole opening device as shown in Fig. 37, fixed with the film press
653, and holes are opened by driving the punch 651 by the punch driving source 652.
In this example, the discharging orifice diameter is made 3.2 µ and the pitch 70.5
µ. Generally speaking, in the case of hole opening by means of a press, punching sag,
burr are generated, but in this example, the influence is made null by making the
punching sag an adhesive, and further generation of the burr could be inhibited by
controlling the clearance of the die 652 of the punch 651 to about 1 µ.
[0194] Thus, according to this example, a highly precise ink jet head can be obtained by
forming ink discharging orifices by press working of a plate body with a multilayer
structure.
[0195] In another method of the present invention, as shown in Figs. 38A to 38C, there is
formed a pattern of the resin layer 708a corresponding to the desired arrangement
stage of discharging orifices on the surface of a substrate 707, comprising a metal
plate, Si, a glass plate, Si, a glass plate having an electroconductive layer provided
thereon, having electroconductivity, and from which the metal layer 709 formed later
is peelable.
[0196] When the metal layer 709 as described below is demanded to have high uniformity,
smoothness, etc., it is preferable to use a substrate having a metal film such as
of aluminum, metal, titanium, etc. formed by such method as sputtering, etc. on a
substrate with better plane characteristic, smoothness such as glass, Si, etc.
[0197] Formation of the resin layer pattern 708a can be performed by laminating a photosensitive
resin layer 708 on the surface of the substrate 707 as shown in Fig. 38B, then exposing
the photosensitive resin layer 708 through a desired pattern to light, or spot irradiating
the photosensitive resin layer 708 in a desired pattern, and developing the photosensitive
resin layer 708 after exposure, thereby leaving the pattern of the resin layer 708a
to remain on the substrate surface.
[0198] For formation of the pattern of the resin layer 708a, the method utilizing photolithography
as described above is not limitative, but other various methods can be used.
[0199] Next, as shown in Fig. 38D, on the surface of the substrate where the resin layer
708a is provided, a metal layer 709 which is the constituent material of the discharging
orifice plate is formed by electroforming, and then water repellent treatment is applied
on the metal layer 709 surface as shown in Fig. 38E to form the layer 710 of water
repellent treatment agent.
[0200] For formation of the metal layer 709, a material having necessary rigidity and satisfactory
characteristics to ink may be suitably selected and used for the discharging orifice
plate. For example, nickel, etc. can be utilized.
[0201] For water repellent treatment of the metal layer 709, by using one suitably selected
from various water repellent treatment agents conventionally used for water repellent
treatment of metal surfaces in view of the material of the metal layer 709, etc.,
the conditions for obtaining good water repellent treatment effect may be set.
[0202] After the water repellent treatment, the metal layer 709 is peeled off from the surface
of the substrate 707 to provide a metal plate (Fig. 38F). Next, after providing an
adhesive layer 711 on the lower surface of the metal plate 709 (Fig. 38G), and further
protective said adhesive layer 711 with an appropriate film (not shown), the resin
708a is treated with an appropriate liquid for dissolution and removal thereof to
remove the resin 708a from the metal plate 709, thereby forming a void portion (thru-hole)
for forming the discharging orifice from which the resin 708a, is withdrawn to obtain
a discharging orifice plate (Fig. 38H).
[0203] As the method for applying the water repellent treatment agent onto the metal layer
709 surface and forming the adhesive layer 711, other than the coating method as described
above, there can be utilized the method in which the metal layer is peeled off previously
from the substrate to be taken out as the plate before performing the water repellent
treatment, one surface of said plate is sprayed with the water repellent treatment
agent, while the other surface with an adhesive (711) either with a time difference
or simultaneously; the method in which a water repellent treatment agent layer formed
on an appropriate base material such as Mylar film, etc. is superposed on one surface
of said plate, pressed with rollers, etc., and further a water repellent treatment
agent formed on an appropriate base material such as Mylar film, etc. is formed on
the other surface, pressed with rollers; or the method in which a water repellent
treatment agent layer formed on an appropriate base material such as Mylar film, etc.
on one surface of said plate, and also a water repellent layer formed on an appropriate
material such as Mylar film, etc. is superposed on the other surface, and the whole
composite is pressed all at once.
[0204] The discharging orifice plate thus obtained has one surface subjected to the water
repellent treatment and the other surface having an adhesive layer which can be utilized
for bonding to a bonding member having liquid channels, etc. formed thereon which
becomes the ink passage for formation of ink jet recording head.
[0205] In the method as described above, since the portion which becomes the orifice of
the metal plate is filled with the resin 708 during the water repellent treatment,
the water repellent treatment will not extend to the portion which becomes the orifice
inner surface. Besides, due to the presence of the resin 708, formation of the adhesive
layer 711 can be done more easily.
Example c
[0206] On a predetermined surface of a plate material (thickness 0.5 mm) made of a stainless
steel (SUS 304) which is an electroconductive substrate, a dry film (Laminate HG,
manufactured by Dinachem) was laminated and pattern exposure and developing processing
were applied on said laminate film (thickness 25 µm) to form spot-like resin layers
arranged corresponding to the arrangements of the discharging orifices.
[0207] Next, nickel plating was effected on the spot-like resin layer formed surfaces on
the electroconductive substrate to form a nickel plated layer (thickness 20 µm).
[0208] Further, a solution of a fluorosilicon type KP-801 (trade name) manufactured by Shinetsu
Kagaku as the water repellent agent dissolved at a ratio of 0.01 % by weight dissolved
in Difreon S3 (trade name, manufactured by Daikin Kogyo) was prepared, coated on the
nickel plated layer surface on the electroconductive substrate by the spin coating
method, followed by drying of the coated layer (thickness 1 µm or less) by the heating
treatment under the conditions of 150 °C, 2 hours, to effect the water repellent treatment.
[0209] After completion of the water repellent treatmnet, the electroconductive substrate
and the nickel plated layer were peeled off to give a nickel plate.
[0210] Next, on the peeled surface of the nickel plate from the electroconductive substrate,
an adhesive (Takelite xP-405/xH-8901b, manufactured by Takeda Seiyaku) was coated
to form an adhesive layer (thickness 2 µm), and further a Mylar film was laminated
on said adhesive layer, followed by treatment with an aqueous 3 - 4 % sodium hydroxide
solution and removal of the dry film from the nickel plate, to give a discharging
orifice plate.
[0211] The Mylar film on the discharging orifice plate obtained was peeled off to have the
adhesive layer exposed, and bonded to the main recording head portion having an energy
generating member generating energy used for ink discharging, a discharging signal
applying means onto the energy generating member, ink channels, etc. formed on a substrate
as shown in Fig. 5 to prepare an ink jet recording head. As the result of ink discharging
test, the slippage angle from the predetermined discharging direction is 1° at the
maximum, and also no nondischarging occurred because there was no progress of the
water repellent into the inner portion of the discharging orifice. Also, when discharging
was performed for a long time, there was no unnecessary pooling of ink on the surface,
whereby stable discharging could be persisted.
Example d
[0212] After a discharging orifice plate was obtained in the same manner as in Example c
except for using the product obtained by sputtering an aluminum coating layer on a
Si substrate surface as the substrate for formation of the discharging orifice plate,
an ink jet recording head was prepared.
[0213] In the recording test in the ink jet recording head obtained, the slippage of ink
droplets from the predetermined shooting spots was 25 to 30 µm, and hence its printing
was found to be improved as compared with that of the prior art.
[0214] Also, although the heater 108 can be formed by use of the same material as the heat
generating resistance layer of the discharging heater 105 (e.g. HfB₂), it may be also
formed by use of other materials constituting the heater board, such as aluminum,
tantalum, titanium, etc.
[0215] Fig. 39 shows a constitutional example of the ceiling plate material for constituting
the ceiling plate 400 according to another embodiment.
[0216] The ceiling plate material 400' is made to have a desired number of ink channel grooves
411, 412, ... (two in the Figure for brevity) and an orifice plate portion 404 provided
integrally.
[0217] In the constitutional example shown in Fig. 39, the ceiling plate material 400' is
simultaneously molded integrally together with the orifice plate portion 404 by use
of a resin excellent ink resistance such as polysulfone, polyethersulfone, polyphenyleneoxide,
polypropylene, etc. The orifice plate portion 404 may be also formed of the same resin
material as the main body portion of the ceiling plate material 400' or another kind
of resin material, which may be prepared separated from the main portion of the ceiling
plate material 400' and inserted into the mold for insert molding.
[0218] As for the ink flow channel groove, the resin can be molded with a mold having a
reverse pattern thereto formed by such method as cutting, etc., whereby the flow channel
grooves 411, 412 can be formed on the ceiling plate 400.
[0219] The orifice plate 404 having thus integrally molded has a thickness of about 50 to
100 µm in molding. Although the orifice can be also formed under this state, but practically
the flow channel length of that portion should be desirably 20 µm or less. This is
because, if the flow channel length from the discharge heater 101A is large, discharging
performance is influenced thereby. Accordingly, in this example, particularly the
portion over the range where orifices to be formed are arranged corresponding to the
grooves 411, 412 of the orifice plate portion 404 is worked to be made thin before
formation of the orifices. In this example, excimer laser was used for working.
[0220] Fig. 40 is a schematic illustration of a device for performing working by use of
such excimer laser. Here, 450 is an excimer laser oscillator (in this exmaple, it
is made a Kr-F excimer laser oscillator), 451 is a lens of, for example, f value of
500 mm for converging laser beam 452. 453 is a mask comprising a plate of Al, etc.
with a thickness of, for exmaple, 1 mm having a hole pattern corresponding to the
worked portion. The ceiling plate material 400' is arranged adequately so that the
surface to be worked may be irradiated by laser beam through the lens 451 and the
mask 453.
[0221] In the step of making the orifice plate portion 404 thin, the laser beam emitted
from the Kr-F excimer laser oscillator 450 is irradiated on the orifice plate 404
through the mask 453 having a hold of, for example, rectangular shape formed thereon.
The orifice plate 404 becomes thin by working only of the portion where irradiated
with excimer laser.
[0222] Fig. 41A exhibits such state, where 465 is the grooved portion made thin by said
working. At this time by controlling adequately the strength of laser and the working
time, the thickness of that portion could be made about 10 to 20 µm.
[0223] Next, the orifice plate 404 is subjected to the liquid repellant treatment, because
the surface having liquid repellancy has the effect to wetting of unnecessary ink,
etc. In this example, as the liquid repellant, DEFENSA from Dainippon Ink diluted
with Difreon S-3 from Daikin to 1 % is coated. Next, for curing of the liquid repellant,
UV-ray irradiation is effected.
[0224] Next, orifices corresponding to flow channels are formed by working with excimer
laser. This can be done by replacing the mask having formed the holes corresponding
to the orifices with the above mask in Fig. 40. After replacement, registration is
effected, lowered by irradiation of laser to form orifices 406. Thus, the ceiling
plate 400 as shown in Fig. 41B can be received. In Fig. 41B, for brevity, 4 orifices
(or flow channels) are provided.
[0225] Concerning also grooves 411, 412 for flow channel formation and the common liquid
chamber portion, these may be also worked with excimer laser, or these may be also
worked after formation of the discharging outlet (orifice) portions. Also, when the
length of the flow channel length in front of the discharging heater poses no problem,
the orifice plate portion 404 is not necessarily made thin depending on the constitution.
[0226] Then, the heater board 100 is abutted against the orifice plate 404 as shown by the
chain line to be bonded thereto, thereby giving a main recording head.
[0227] According to such constitution as described above, since no registration or adhesion
between the ceiling plate and the orifice plate required as in the prior art, there
is no registration error or positional slippage during adhesion at all, whereby reduction
in defective products and shortening of the steps could contribute to bulk productivity
and lowering in cost of the recording head. Also, since there exists no adhesion step
between the ceiling plate and the orifice plate, there is no fear of clogging of the
orifices or ink flow channels by flowing of the adhesive. Further, since the position
can be determined of the flow channel direction by abutting the heater board 100 against
the end surface on the opposite side to the end surface on the discharging side of
the orifice plate portion 404 during bonding of the heater board 100 and the ceiling
plate 400 integrally made with the orifice plate portion 404, the whole registration
step and assembling step can be made easier. In addition, there is also no fear of
peel-off of the orifice plate as in the prior art.
[0228] Fig. 42 shows another embodiment of the present invention in which orifice working
is performed by excimer laser beam on the orifice plate formed integrally with the
ceiling plate, and the same elements as those shown in Fig. 40 are attached with the
same symbols. In Fig. 40, 450 is a laser oscillating device for oscillating KrF excimer
laser beam, 452 a pulse laser beam with a wavelength of 248 mm and a pulse width of
about 15 nsec oscillated from the laser oscillating device 451, 453 a synthetic quartz
lens for converging the laser beam 452, 454 a projection mask having aluminum capable
of shielding the laser beam 452 vapor deposited thereon, on which a plurality of holes
of 133 µm in diameter are arranged at a pitch of 212 µm to constituted an orifice
pattern.
[0229] Fig. 43A shows a constitutional example of the ceiling plate 457 according to this
example.
[0230] The ceiling plate 457 according to this example is made to have a desired number
of ink channel grooves 464 and ink discharging orifices 466 formed on the orifice
plate 460 corresponding thereto (two in the Figure for brevity) and an orifice plate
portion 10 provided integrally.
[0231] In the constitutional example shown in Fig. 43A, the ceiling plate material 457 is
simultaneously molded integrally together with the orifice plate 460 by use of a resin
excellent in ink resistance such as polysulfone, polyethersulfone, polyphenyleneoxide,
polypropylene, etc.
[0232] Next, the methods for forming the ink channel groove 464 and the orifice 466 are
described.
[0233] As for the ink channel groove, a resin can be molded with a mold having a fine groove
of reverse pattern thereto by such method as cutting, etc., and with the use of the
mold, liquid channel groove 464 can be formed on the ceiling plate 457.
[0234] As for formation of orifice, within the mold, molding is effected under the state
having no orifice 466 and excimer laser beam is irradiated by a laser device on the
positions where orifices are to be formed from the ink channel side on the orifice
plate 10 as explained in Fig. 42, followed by removal and evaporation of the resin,
to form orifices 466.
[0235] The details of orifice formation are shown in Fig. 43B. As is apparent from Fig.
43B, the excimer laser beam 452 is irradiated on the orifice plate 460 through the
mask 454 as described above from the ink channel side 464. The excimer laser 452 is
converged at ϑ₁ = 2° on one side with respect to the optical axis 463, and irradiated
from the vertical direction of the orifice plate 460 with the optical axis 463 being
slanted at ϑ₂ = 10°.
[0236] Thus, by irradiation of the laser beam from the ink channel side, the cross-sectional
area of the orifice having a tapered shape becomes reduced toward the discharging
direction.
[0237] Fig. 44 is a perspective view of the main recording head constituted by bonding of
the heater board 458 and the ceiling plate 457 as described above.
[0238] As shown in Fig. 44, the heater board 458 having the discharging heater 101A, etc.
is bonded to the orifice plate 460 to obtain the main recording head.
[0239] According to such constitution as described above, since no registration or adhesion
between the ceiling plate and the orifice plate required as in the prior art, there
is not registration error or positional slippage during adhesion at all, whereby reduction
in defective products and shortening of the steps could contribute to bulk productivity
and lowering in cost of the recording head. Also, since there exists no adhesion step
between the ceiling plate and the orifice plate, there is no fear of clogging of the
orifices or ink flow channels by flowing of the adhesive. Further, since the position
can be determined of the flow channel direction by abutting the heater board 458 against
the end surface on the opposite side to the end surface on the discharging side of
the orifice plate 460 during bonding of the heater board 458 and the ceiling plate
460 integrally made with the orifice plate 460, the whole registration step and assembling
step can be made easier. In addition, there is also no fear of peel-off of the orifice
plate as in the prior art.
[0240] Figs. 46A and 46B show another example of the present invention, and are repsectively
a perspective view and a sectional view of a ceiling plate having an orifice plate
integral formed therewith.
[0241] This example has made the irradiation angle, namely ϑ₂ as described above 45° corresponding
to the shapes of the ceiling plate and the orifice plate. Thus, when laser beam is
irradiated from the ink channel side, its irradiation angle is varied corresponding
to the shape of the ceiling plate, etc.
[0242] Comparison of the results when recording was performed with the recording heads constituted
by the above-mentioned two examples and the recording head of the prior art shown
in Fig. 46 is shown in the following table.
|
Droplet discharging speed (average of 10 heads) |
Recording result |
Example (Fig. 43) |
8 m/s ± 10 % |
Good |
Example (Fig. 45) |
9.3 m/s ± 8 % |
Good |
Reference example (Fig.46) |
4 m/s ± 40 % |
Passable |
[0243] As is apparent from the above table, when the recording head according to this example
is used, the discharging speed is increased to two-fold or more, and consequently
the shooting position precision of droplet can be improved to give good recording
result. Also, when having such orifice shape as in this example, the volume of discharged
liquid is understood to become larger, and this gives better result to the recording
density.
[0244] In the above-mentioned two examples, the orifice plate and the ceiling are integrally
combined, but application of the present invention is not limited thereto, but the
desired effect can be of course obtained by bonding separately to the ceiling plate,
and then applying the orifice working as described above thereon.
[0245] Fig. 47 is a perspective view showing one example of ceiling plate 400 shown in Fig.
7, representing the groove 403 for common liquid chamber and the groove 402 (dotted
line) for ink channel, and the ceiling plate 400 is a resin molding. As the resin
material, polyether sulfone, polyether ether ketone excellent in ink resistance can
be used. Molding of the ceiling plate 400 is performed by use of a commercially available
injection molding machine and a mold forming a pair with the shape shown in Fig. 47.
[0246] On completion of injection molding, then after registration between the mask 453
having a transparent portion 713 and a nontransparent portion 714 corresponding to
the pattern of the ink channel to the laser beam 452 of excimer laser as shown in
Fig. 49, the resin molding surface shown in Fig. 47 is removed and eliminated with
the laser beam passed through the transparent portion of the excimer laser beam to
obtain a groove shape of ink channel as shown in Fig. 50.
[0247] The excimer laser used in this example is KrF excimer laser and also Arf excimer
laser can be used.
[0248] As the mask material, a quartz substrate is used and the opaque portion 714 of the
mask 453 is formed by Cr vapor deposition. The width 703 of the ink channel groove
is made 32 µm corresponding to the constitution having 16 discharging outlets per
1 mm, and width 704 of the non-groove portion is made 31.5 µm.
[0249] Further, by irradiating KrF excimer laser by use Index 200 manufactured by Lumonix,
Canada by way of 360 pulse irradiation at an energy density of 350 mJ/cm² per one
pulse, a groove depth 705 of 30 µm is obtained.
[0250] From the above process, the resin molding shown in Fig. 47 becomes the ceiling plate
having fine grooves for ink channel integrally as shown in Fig. 48.
[0251] Next, the ceiling plate 400 after being precisely washed is bonded to the heater
board 100 having energy generating elements 101A such as heat generating elements,
etc. arranged on a substrate which can be formed of glass, ceramics, Si, plastic,
or metal, etc. as shown in Fig. 51 to constitute the main head 780.
[0252] In the Figure 741 is ink discharging outlet (orifice) in the main head 780.
[0253] Fig. 52 is a schematic view of an apparatus showing manufacturing manner of the orifice
according to another embodiment. In Fig. 52, 450 is an excimer laser generating device,
451 is a lens for collecting laser beams 452 outputted from the generating device
451, 453 is a mask disposed between the generating device 450 and the orifice plate,
40 is an orifice on which the orifice is formed, 413 is a lens for collecting the
laser beam for perforating the discharge opening on the orifice plate by projecting
the mask 413.
[0254] Fig. 53 is a perspective view for showing detail of the mask 453 and orifice plate
40. On the mask 453 a transparent portion 91 is provided corresponding to a portion
at which the orifice of orifice plate 40 is worked for causing the laser beam to transmit.
In detail, the pattern provided on the mask 453 as the orifice will be worked on the
film of orifice plate.
[0255] As shown in Fig. 53, although the number of orifice is plural this is merely illustrative.
In fact, in the present embodiment the mask in which orifices of 360 DPI, φ33 µm are
arranged side by side linearly is used. In this construction, the laser beam 452 is
irradiated to the plate 40 via the mask 453 to form the orifice. It is desirable for
the mask not to be affected by heat due to laser irradiation, and for this reason
material of low thermal coefficiency such as metal (for example Be-Cu) can be adopted.
[0256] In the orifice of orifice plate thus manufactured, there is no abnormal deformation
around the orifice and circular configuration exactly following the configuration
of the mask can be formed on the front and rear surfaces, which can be formed by such
as carbon dioxide gas laser or YAG laser.
[0257] Fig. 54 and Fig. 55 show respectively a schematic illustration of a preferable orifice
working device for practicing the method for preparing the recording head of the present
invention and a perspective view representing the details of the mask and the orifice
plate obtained by said preparation method.
[0258] In this example, first, a glass material applied with grooving as the ceiling plate
400 and a heater board 100 having energy generating elements and wirings therefore,
etc. provided on a Si wafer are bonded together, and then the bonded surface is subjected
to ozone washing of the orifice plate 40, the ceiling plate 400 and the heater board
100, followed by coating of a silane coupling agent. The coating method is performed
by transfer from a silane coupling agent A-187 (from Nippon Unicar K.K.) spin coated
on a Si rubber of φ 100, t = 0.6.
[0259] Next, a dry film (Tokyo Ohka K.K. Se-320) as the material of the orifice plate 40
after peel-off of the protective film, polyether on one side is heated to about 40
- 80 °C. At this time, the ceiling plate 400 and the heater board 100 integrally combined
are also heated at the same time. This heating is performed by use of a hot plate
or a clean oven in this example.
[0260] After the dry film is heated for one minute, the dry film surface of the film and
the ceiling plate-heater board are pushed against each other under a pressure of 2
to 10 kg/cm² for 1 to 10 seconds to be bonded together. Next, the composite is cooled
gradually to room temperature (about 25 °C), followed by separation of the film from
the ceiling-heater board. At this time, the dry film which becomes the orifice plate
is separated from the other protective film of Mylar film to be bonded to the ceiling-heater
board. Next, UV-ray is irradiated on the bonded dry film surface to effect curing
of the film, and the recording head (ceiling plate-heater board-orifice plate) is
fixed at a predetermined position comprising the constitution shown in Fig. 54, followed
by registration of the recording head, the excimer laser and the mask. This registration
is corresponded by making the stand 207 for fixing the recording head movable system
in this example. After completion of registration, excimer laser light is irradiated
on the orifice plate 40 through the mask 453 to effect working of the orifice 41.
[0261] According to the method as described above, it is not necessary to perform bonding
by registration with high precision between the orifice plate having fine orifices
and the ceiling-heater board, whereby the preparation steps of the ink jet recording
head become simple.
[0262] Next, an example for making the orifice shape a more preferable shape by working
with excimer laser is shown.
[0263] The orifice shape of the ink jet recording head in this example has been deemed to
have desirably a shape which is narrower at the tip as nearer from the ink channel
804 toward the orifice 805. However, because it can be realized with difficulty in
the preparation method of the prior art, most of its shape have been columnar.
[0264] Whereas, by use of excimer laser, and utilizing the specific feature that the shape
of the hole is varied by changing the position of the focus by moving gradually the
focusing lens during irradiation in working only of the orifice plate, also a converging
orifice shape can be produced.
[0265] The principal part of the recording head prepared as described above is constituted
as shown in Fig. 56. Shortly speaking, the angle ϑ of the discharging orifice 805
formed on the orifice plate 802 differs for each liquid channel 804, whereby the droplet
will fly with curving of the discharging direction 807 for each discharging orifice
805 in substantially the same angle as the discharging orifice angle. For this reason,
the recorded dot pitch d formed on the surface to be recorded 806 can be made smaller
than the liquid channel pitch d' of the recording head.
[0266] Accordingly, as compared with the recording head of the prior art having the same
recording pitch and discharging orifice pitch, the discharging orifice width can be
taken larger, and also it has become possible to take also larger width of the discharging
energy element. For this reason, energy efficiency can be improved to enhance the
discharging speed. Further, since the cross-sectional area of the liquid channel can
be enlarged, supplement of ink to the liquid channel becomes smooth, and therefore
response frequency can be also improved, and further overall improvement of image
quality can be improved.
[0267] Further, in the ink jet recording head shown in Fig. 56, by making the diameter of
the discharging orifice at the outside portion smaller as compared with the discharging
orifice at the central portion, the speed of the ink droplet discharged from the discharging
orifice at the central portion with shorter flight length of the ink droplet can be
made greater as compared with the speed of the ink droplet discharged from the discharging
orifice at the outside portion with longer flight length of the ink droplet, and therefore
the timings of the ink droplets shot finally onto the recording medium can be made
the same very easily when the timings of the ink droplets discharged from the discharging
orifices and their driving forces are the same for the respective discharging orifices.
[0268] In the examples as described above, the discharging orifice angles of the respective
discharging orifices are formed in the converging direction, but in the present invention,
if necessary, the discharging angles can be set variously for the respective discharging
orifices.
[0269] For example, it is possible to constitute so that the above-mentioned incident angle
may be different from the angle formed between the plane which is vertical to the
above-mentioned discharging orifice surface and formed between the direction in which
above discharging orifices are juxtaposed and the direction in which the ink is discharged
from the above discharging orifices, and the above discharging orifice surface.
[0270] In the following, another example is described.
[0271] Fig. 57 is a schematic view of an ink jet recording head according to another example
of the present invention, which head is disposable with an ink tank integrally combined.
[0272] The ink jet recording head shown in Fig. 57 is provided with four main recording
heads, each constituted by bonding a ceiling plate having a concavity (hereinafter
called "groove") for constituting ink channels and common liquid chamber, and further
a discharging orifice forming member (orifice plate) 802 integrally formed and a substrate
(hereinafter called "heater board") having an electricity-heat converter for generating
discharging energy (hereinafter called "discharging heater") and an Al wiring for
supplying electrical signals thereto formed by the film forming technique on a Si
substrate.
[0273] Also, in the Figure, 600 is a sub-ink tank arranged adjacent to the main recording
head, and the sub-ink tank 600 and the above main body are supported by lids 300 and
800. Further, 1000 is a main cartridge and 1100 is the lid member of the main cartridge.
Internally of the main cartridge is built in an ink tank, which supplies suitably
ink to the sub-ink tank 600.
[0274] Figs. 58A and 58B show the manner in which orifice working is performed by excimer
laser beam on the orifice plate formed integrally with the ceiling plate. That is,
Fig. 58A is a schematic view of the device in which the laser beam is incident so
as to form discharging orifices from the ceiling concavity side, and Fig. 58B from
the discharging orifice side. In the same Figure 450, is a laser oscillating device
for oscillating KrF excimer laser beam, 452 a pulse laser beam with a wavelength of
248 mm and a pulse width of about 15 nsec oscillated from the laser oscillating device
450, 451 a synthetic quartz lens for converging the laser beam 452, 453 a projection
mask having aluminum capable of shielding the laser beam 452 vapor deposited thereon,
on which a plurality of holes of 133 µm in diameter are arranged at a pitch of 212
µm to constituted an orifice pattern.
[0275] 460 is an orifice plate for forming the discharging orifices and 801A is an ink jet
recording head, both of which is fixed on an implement 207A which can be freely rotated
relative to the laser beam 452.
[0276] The principal portion of the recording head prepared as described above has the constitution
as shown in Fig. 59.
[0277] Shortly speaking, the discharging angle ϑ of the discharging orifice 909 formed on
the orifice plate 902 differ for each head 901, and therefore the droplet will fly
with the discharging direction 911 of each head being curved substantially the same
as the discharging angle. Accordingly, the recording dot pitch d'' for each discharging
orifice row formed on the surface to be recorded 210 can be made smaller than the
distance d''' between the discharging orifice rows of the recording head.
[0278] In the recording head having a plurality of discharging rows of the prior art, since
the distance between the respective discharging orifice rows is the same as the recording
dot row distance, greater memory size is required for taking timing for each recording
dot row, but in the present invention, the distance between the recorded dot rows
can be taken smaller, whereby the cost of the main printer can be made lower. Particularly,
such constitution is very effective in the case of color printing where the discharging
orifice rows must be divided corresponding to the respective colors.
[0279] Fig. 60 shows an embodiment which bonds or fixes the heater board 100 and the ceiling
plate 400. In Fig. 60, for simplification, the orifice plate portion 404 of the ceiling
plate 400 is shown by the chain line, and showing of the wiring pattern on the heater
board 100 is omitted.
[0280] As described above, the registration of the heater board 100 and the ceiling plate
400 is performed by abutting the end surface of the heater board 100 against the orifice
plate portion 404, and in bonding of these, the adhesive 405 was coated along the
3 sides of the peripheral portion of the ceiling plate 400. By doing so, flowing of
the adhesive into the ink flow channel could be inhibited. Further, it is also possible
to permit an adhesive to exist over a suitable range in necessary and sufficient amount
at the bonding surface between the heater board 100 and the orifice plate 404.
[0281] In this example, as the adhesive 405, a photocurable type adhesive UV-201 (Grace
Japan K.K.) is used, and after registration cured by irradiation with UV-ray of, for
example, 10 - 30 J/cm² to fix the both. Here, since the existing portion of the adhesive
405 is apart from the discharging outlet, the tolerable value of trial number during
registration is increased.
[0282] Next, the main recording head obtained by integration of the ceiling plate 400 and
the heater board 100 in this way is fixed onto the support 300 by use of an adhesive
306. As the adhesive 306, for example, HP2R/2H manufactured by Canon Chemical K.K.
can be employed.
[0283] Under this state, both the substrates (the heater board 100 and the ceiling plate
400) are adhered only at the peripheral portions other than the flow channel portion
as described above, and no sufficient adhesion is obtained. Accordingly, an urging
force of the pressing spring 500 is permitted to act from the upper side of the ceiling
plate 400. The pressing spring 500 can be formed by use of, for example, phosphorous
bronze or stainless steel for spring. By fitting the nails 507 provided at the lower
portions of both ends into the hole portions 307 provided at the support 300 to thereby
engaging the both, mechanical pressure is applied from the upper portion of the ceiling
plate 400. In this way, sufficient adhesion state between the both substrates can
be obtained. In the pressing spring 500, 520 is a hole which receives insertion of
the feeding pipe for connecting the ink introducing inlet 420 of the ceiling plate
400 to the ink feeding inlet on the feeding tank 600 side.
[0284] In this example, in bonding of the ceiling plate 400 with the heater board 100, a
photocurable type adhesive is used, but its form may be any desired one or no adhesive
may be required to be used, if sufficient fixing force or adhesion force can be obtained
with the pressing spring 500. For example, only for the purpose of enhancing liquid
sealability, a suitable sealing material, namely a sealing member such as sealant
or rubber packing, etc. can be used. Also, similarly, if sufficient fixing force of
the main head body can be obtained through engagement between the nail 507 of the
pressing spring 500 and the hole portion 307 of the support 300, no adhesive 306 may
be employed.
[0285] According to this example, since sufficient bonded state can be obtained without
coating of an adhesive on the surface of the flow channel wall of the ceiling plate
400, the coating step of the adhesive can be simplified. Also when slippage occurred
during registration in the prior art, there was a fear of sticking of adhesive to
the flow channel portion at the discharging heater 105, etc. of the heater board 100,
or occurrence of defective product by clogging of the flow channel or discharging
outlet with adhesive, but no such phenomenon occurs in this example, and registration
can be done for many times. Further, presence of more or less deformation, warping
or variance in product in the ceiling plate by use of a resin material is permissible
and therefore the manufacturing steps can become simple.
[0286] Fig. 61 is a modification example of the constitution shown in Fig. 60. In this Figure,
showing of the orifice plate 404 in the ceiling plate 400 is omitted.
[0287] In this example, similarly as in the example shown in Fig. 60, the structure is made
to obtain sufficient adhesion by applying pressure with a plate spring 500 in flat
shape from the upper surface of the ceiling plate 400 under the state where the main
recording head comprising the heater board 100 and the ceiling plate 400 is bonded
to the support 300. The plate spring 500 is further pressurized by another member
of the upper part (e.g. feeding tank 600 in Fig. 7).
[0288] Also, according to this example, the same effect as in the constitution shown in
Fig. 60 could be obtained.
[0289] By assembling the respective parts with the constitutions as described above according
to the steps in Fig. 7A, the cartridge as shown in Fig. 7B can be obtained and further
an ink jet printer as shown in Fig. 62, namely an ink jet printer by use of a disposable
cartridge can be constituted by use of this.
[0290] In Fig. 62, 14 is the cartridge shown in Figs. 7A and 7B, the cartridge 14 is fixed
on the carriage 15 by a pressing member 41, and these are made reciprocally movable
in the lengthy direction along the shaft 21. Also, registration relative to the carriage
15 can be effected by, for example, the hole provided on the support 300 and the dowel
provided on the carriage 15 side. Further electrical connection may be obtained by
joining of the connector on the carriage 15 to the connecting pad provided on the
wiring substrate 200.
[0291] This ink discharged by the recording head reaches a recording medium 18 with the
recording surface regulated by a platen 9 to form an image on the recording medium
18.
[0292] To the recording head are supplied discharging signals corresponding to the image
data from a suitable data supplying source through the cable 16 and the terminals
connected thereto. The cartridge 14 can be provided in one or plural number (two in
the Figure) corresponding to the ink colors, etc. used.
[0293] In Fig. 62, 17 is a carriage motor for scanning the carriage 15 along the shaft 21,
22 is a wire for transmitting the driving force of the motor 17 to the carriage 15.
20 is a feed motor jointed with the platen roller 19 for conveying the recording medium
18.
[0294] In the ink jet printer by use of such disposable cartridge 14, the cartridge 14 is
changed when there is no ink impregnated in the absorber 900, etc., and for that purpose,
the cartridge 14 is desired to be low in cost. Since the cartridge 14 as described
in the above examples can be produced by simple production steps and also with small
number of steps, and therefore it can be constituted at low cost and is extremely
suitable for disposable construction. Further, registration in assembling of the main
recording head can be done correctly, and yet there occurs no variance in dimension
or clogging of the flow channel, etc. by flowing of the adhesive, reliability is very
high and also yield can be improved.
[0295] The present invention is not limited to the examples as described above, but various
constitutions can be employed as a matter of course.
[0296] For example, in the above examples, the main recording head the ink supplying source,
etc. are made integral and disposable, but the both may be separate bodies, and each
is not necessarily required to be made disposable. This is because, even the main
recording head may be the fixed type without the condition of simple exchange, simple
and inexpensive constitution as described above will also constitute to the reduction
in cost of the main printer.
[0297] Also, for the main recording head comprising the heater board 100 and the ceiling
plate 400, ink flow channels and concavity for formation of the common liquid chamber
are provided only on the ceiling plate side in the above examples, but these can be
also provided on both thereof. Also, concerning the main recording head, discharging
heater 105 is used so as to make the heat energy discharging energy in the above examples,
an electricity-mechanical converting element which is deformed corresponding to current
passage may be used to utilize the mechanical vibration as the discharging energy.
[0298] Further, in the above examples, the orifice plate portion 404 itself is made a constitution
having the abutting portion against the heater board, but the shape, etc. of the abutting
portion may be any desired one. For example, such abutting portion may be also provided
in the side surface direction so as to effect registration in the lateral direction,
or in place of providing such abutting portion, the registration may be made through
the combination of dowel and hole. Also, if the registration poses no problem, no
abutting portion or registration member is necessary. In other words, the ceiling
plate may be in the form having the wall portion with the same surface as the bonding
surface in front of the groove portion and having the discharging outlet formed thereat.
[0299] In addition, in the above examples, the ceiling plate and the heater board are adhered
and bonded with a pressing spring, but if there is no problem in use only of an adhesive
during said bonding, it is also possible to use a constitution without use of a pressing
spring.
[0300] The present invention brings about excellent effects particularly in a recording
head, recording device of the bubble jet system among the ink jet recording system.
[0301] As to its representative constitution and principle, for example, one practiced by
use of the basic principle disclosed in, for example, U.S. Patents 4,723,129 and 4,740,796
is preferred. This system is applicable to either of the so called on-demand type
and the continuous type. Particularly, the case of the on-demand type is effective
because, by applying at least one driving signal which gives rapid temperature elevation
exceeding nucleus boiling corresponding to the recording information on an electricity-heat
convertors arranged corresponding to the sheets or liquid channels holding liquid
(ink), heat energy is generated at the electricity-heat convertors to effect film
boiling at the heat acting surface of the recording head, and consequently the bubbles
within the liquid (ink) can be formed corresponding one by one to the driving signals.
By discharging the liquid (ink) through an opening for discharging by growth and shrinkage
of the bubble, at least one droplet is formed. By making the driving signals into
pulse shapes, growth and shrinkage of the bubble can be effected instantly and adequately
to accomplish more preferably discharging of the liquid (ink) particularly excellent
in response characteristic. As the driving signals of such pulse shape, those as disclosed
in U.S. Patents 4,463,359 and 4,345,262 are suitable. Further excellent recording
can be performed by employment of the conditions described in U.S. Patent 4,313,124
of the invention concerning the temperature elevation rate of the above-mentioned
heat acting surface.
[0302] As the constitution of the recording head, in addition to the combination constitutions
of discharging orifice, liquid channel, electricity-heat converter (linera liquid
channel or right angle liquid channel) as disclosed in the above-mentioned respective
specifications, the constitution by use of U.S. Patent 4,558,333, 4,459,600 disclosing
the constitution having the heat acting portion arranged in the flexed region is also
included in the present invention. In addition, the present invention can be also
effectively made the constitution as disclosed in Japanese Patent Laid-Open Application
No. 59-123670 which discloses the constitution using a slit common to a plurality
of electricity-heat convertors as the discharging portion of the electricity-heat
converter or Japanese Patent Laid-Open Application No. 59-138461 which discloses the
constitution having the opening for absorbing pressure wave of heat energy correspondent
to the discharging portion.
[0303] Further, as the recording head of the full line type having a length corresponding
to the maximum width of recording medium which can be recorded by the recording device,
either the constitution which satisfies its length by combination of a plurality of
recording heads as disclosed in the above-mentioned specifications or the constitution
as one recording head integrally formed may be used, and the present invention can
exhibit the effects as described above further effectively.
[0304] In addition, the present invention is effective for a recording head of the freely
exchangeable chip type which enables electrical connection to the main device or supply
of ink from the main device by being mounted on the main device, or for the case by
use of a recording head of the cartridge type provided integrally on the recording
head itself.
[0305] Also, addition of a restoration means for the recording head, a preliminary auxiliary
means, etc. provided as the constitution of the recording device of the present invention
is preferable, because the effect of the present invention can be further stabilized.
Specific examples of these may include, for the recording head, capping means, cleaning
means, pressurization or aspiration means, electricity-heat convertors or another
heating element or preliminary heating means according to a combination of these,
and it is also effective for performing stable recording to perform preliminary mode
which performs discharging separate from recording.
[0306] Further, as the recording mode of the recording device, the present invention is
extremely effective for not only the recording mode only of a primary stream color
such as black etc., but also a device equipped with at least one of plural different
colors or full color by color mixing, whether the recording head may be either integrally
constituted or combined in plural number.
[0307] Summing up, according to the one aspect of the present invention, it is possible
to omit the step for adhering the discharge opening forming member (orifice plate)
in the assembling process of the recording head, which enables to omit or exclude
the positioning upon adhering and to overcome the disadvantage such as clogging in
the liquid path since no adhesive agent is used. Thus, whole of the manufacturing
process of the recording head can be simplified. In the case the discharge opening
forming member is partially thinned to form the discharge opening thereat, formation
of the discharge opening is simplified and length of the liquid flow path located
in front of discharge energy generating element can be shortened.
[0308] According to another aspect of the present invention, the cheap but reliable ink
jet recording head can be obtained by the simple manufacturing process in the small
number of process.
[0309] According to other aspect of the present invention, it is possible to form the orifice
on the orifice plate with high density, in high accuracy and under accurate positioning
relative to the ink path or the like. As the result, by using the mask member properly,
more small or fine plural orifices can be manufactured together, so the ink jet recording
head can be manufactured simply and in low cost. Additionally, realization of high
accuracy can improve character of the image to be recorded.
[0310] Furthermore, according to another aspect of the present invention, the discharge
opening can be worked into the configuration desirable for ink discharge, workability
of the discharge opening can be improved, and occurrence of bad influence resulted
from working of the discharge opening can be prevented. As the result, by only adding
the conventional working of the discharge opening to the discharge opening forming
member preformed the discharge quality is increased and bad influence due to water-repellent
treatment or the like can be prevented.
[0311] According to another aspect of the present invention, it is possible to obtain the
ink jet recording head having tapered configuration whose cross-section decreases
with respect to the discharge direction, which enables to stabilize the amount of
ink droplet and the discharge speed necessary for recording. As the result, the discharge
quality such as accuracy of adhering position and recording density is improved and
the recording image at high quality can be obtained.
[0312] According to one embodiment of the present invention, the discharge opening plate
is formed by providing the water repellent cover layer and adhesive agent layer onto
the plate member on which no through hole for forming the discharge opening is formed,
high or difficult technique which becomes necessary when forming these layers after
formation of the through hole is not indispensable. Thus, the through hole can be
worked with high yield and good workability. In addition, since the through hole for
the discharge opening is perforated after formation of the water repellent cover layer
the material for the water repellent cover layer would not go into the through hole,
thus occurrence of problem in the prior art can be prevented.
[0313] Furthermore, since the adhesive layer for attaching the discharge opening plate to
the main body of recording head, the plate can be attached to the main body by using
the adhesive agent layer easily. There is no need for applying the adhesive agent
onto the attaching surface of the main body. In connection therewith, since the adhesive
agent layer is supplied to the periphery of the discharge opening, the problem occurred
in the prior art can be prevented.
[0314] According to another aspect of the present invention, the discharge opening plate
having the water repellent cover layer and the adhesive layer can be obtained by simply
and effective method. Furthermore, the both layers are disposed at the predetermined
position in the predetermined condition accurately, thus entry of these layers into
the discharge opening can be prevented. For this reason, in the recording head usings
the discharge opening plate of the present invention, the manufacturing yield is improved,
the poor ink discharge due to ink clogging at the discharge surface and connecting
portion between the discharge opening plate and the main body of recording head would
not occur. Thus, the proper printing character can be obtained, and reliability is
increased. Furthermore, by carrying out sequence perforating after the adhesive agent
layer and water repellent cover layer have been formed on for example the large plate,
the treatment for each head which is effected in the prior art can be excluded. Thus,
the process number in the discharge opening plate connecting process can be greatly
decreased to thereby decrease the manufacturing cost of the recording head.
[0315] According to another aspect of the present invention, onto the plate-like member
on which the repellent ink layer, base film and adhesive agents layer sequentially,
or the plate-like member on which the repellent ink layer, base film, adhesive agent
layer and mold release film sequentially, the ink discharge opening is formed by press
working, and the plate-like member is adhered to the surface on which the opening
communicated with the ink path of the head body is formed by the adhesive agent layer,
which enable to prevent occurrence of the clogging of ink discharge opening due to
entry of the ink repellent treatment agent and adhesive agent and mass productivity
will be increased. Furthermore, cheap ink jet head having high accuracy of ink discharge
and the pitch of ink discharge opening can be manufactured.
[0316] According to another aspect of the present invention, because the water repellent
treatment is made only to the portion which constructs outward wall surface of the
discharge opening in the manufacturing process of the discharge opening plate, and
because the through hole which forms the discharge opening upon water repellent treatment
is filled with the resin and would not reach to the inner surface of the discharge
opening, the water repellent treatment can be carried simply and effectively and accurately.
[0317] According to another aspect of the present invention, the water repellent treatment
of the outer surface of the discharge opening plate is carried out securely and effectively
by simple method which adds the applying process of the water repellent treatment
agent during the manufacturing process of the discharge opening plate, which enables
to realize the discharge opening plate of high quality which has been made water repellent
treatment in low cost.
[0318] According to another aspect of the present invention, the ceiling plate in which
the ink groove of fine configuration and the common chamber having several scores
times of the ink path are integrally formed can be formed easily. In addition, high
flatness of accuracy of the ink path can be realized by the working of excimer laser
light. As the result, the process number can be decreased compared with the prior
art, and the bad influence such as positioning shift, leakage of the recording liquid,
flow-in of the adhesive agent into the ink path can be prevented. Thus, the ink jet
recording head in which the ink discharge quality is increased can be obtained.
[0319] According to another aspect of the present invention, the orifice plate can be provided
with each discharge opening angle peculiar to the discharge opening in high density
and high accuracy, and the positional relation between the ink path or the like and
the orifice can be determined accurately.
[0320] According to another aspect of the present invention, the discharge opening is formed
obliquely on the orifice plate in high accuracy, and plural discharge openings (orifices)
of different angle can be formed simultaneously on the plate. In addition, it is possilbe
to form the discharge openings by changing or differenciating the discharge opening
angle as the whole in every row of the discharging opening. As the result, ink jet
recording head capable of effecting the high speed recording of high quality in low
cost and simply.