BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to the papermaking arts, and specifically to the manufacture
of paper tissue and toweling, which may be collectively referred to as bulk tissue.
The present invention also relates to the manufacture of nonwoven articles and fabrics
by processes such as hydroentanglement, melt-blown, spun-bond and air-laid. In particular,
the present invention relates to belts, which have had a functional polymeric resin
material deposited in precise preselected areas onto their base structures to fill
those areas and, when desired, to form a layer of desired thickness thereover. Belts
of this type are used in the manufacture of bulk tissue and towel, and of nonwoven
articles and fabrics.
2. Background of the Invention
[0002] Soft, absorbent disposable paper products, such as facial tissue, bath tissue and
paper toweling, are a pervasive feature of contemporary life in modern industrialized
societies. While there are numerous methods for manufacturing such products, in general
terms, their manufacture begins with the formation of an embryonic paper web in the
forming section of a paper machine. The embryonic paper web is then transferred to
a through-air-drying (TAD) fabric by means of an air flow, brought about by vacuum
or suction, which deflects the web and forces it to conform, at least in part, to
the topography of the TAD fabric. Downstream from the transfer point, the web, carried
on the TAD fabric, passes through a through-air dryer, where a flow of heated air,
directed against the web and through the TAD fabric, dries the web to a desired degree.
Finally, downstream from the through-air dryer, the web may be adhered to the surface
of a Yankee dryer and imprinted thereon by the surface of the TAD fabric, for further
and complete drying. The fully dried web is then removed from the surface of the Yankee
dryer with a doctor blade which foreshortens or crepes the web and increases its bulk.
The foreshortened web is then wound onto rolls for subsequent processing, including
packaging into a form suitable for shipment to and purchase by consumers.
[0003] As noted above, there are many methods for manufacturing bulk tissue products, and
the foregoing description should be understood to be an outline of the general steps
shared by some of the methods. For example, the use of a Yankee dryer is not always
required as in a given situation, foreshortening may not be desired, or other means,
such as "wet creping", may have already been taken to foreshorten the web.
[0004] The present application is concerned, at least in part, with the TAD fabrics used
on the through-air dryer of a bulk tissue machine. Historically, TAD fabrics were
woven from monofilament yarns in weave patterns which provided their paper-supporting
surfaces with knuckles, elevated relative to other areas on the surfaces, having relatively
long floats. Upon transfer from a forming fabric to the paper-contacting surface of
such a TAD fabric, the embryonic paper web would assume, at least in part, the topography
of that surface. As a consequence, the portions of the embryonic paper web deflected
between the knuckles becomes less dense relative to those on the knuckles, ultimately
giving the bulk tissue product softness and absorbency. Upon subsequent pressure transfer
from the TAD fabric to the surface of a Yankee dryer, the knuckles on the paper-contacting
surface of the TAD fabric imprint and densify those portions of the paper web lying
thereon. This densification, in turn, strengthens the bulk tissue product as a whole.
The densification was typically enhanced by abrading or sanding the paper-contacting
surface of the TAD fabric to provide the knuckles with flat surfaces, thereby increasing
the contact area between the paper web and the Yankee dryer, and enlarging the knuckle
imprints to strengthen the bulk tissue product further and to dry it more completely.
[0005] Driven by consumer interest in softer, more absorbent and stronger bulk tissue products,
development initially centered on the weave patterns used to produce TAD fabrics.
For example, in the now expired
U.S. Patents Nos. 4.191,609 and
4,239,065 to Trokhan, which are assigned to the Procter & Gamble Company of Cincinnati, Ohio, TAD fabrics
woven in weave patterns having nonnumerically consecutive warp-pick sequences are
shown. The disclosed weave patterns provide the paper-supporting surfaces of the subject
TAD fabrics with a plurality of wicker-basket-like cavities disposed in a bilaterally
staggered array, each such cavity being bounded by knuckles on the top-surface plane
of the fabric. The TAD fabrics enable a bulk tissue product, having a patterned array
of relatively closely spaced uncompressed pillowlike zones, each zone being circumscribed
by a picket-like lineament comprising alternately spaced areas of compacted fibers
and relatively non-compacted fibers and formed by the top-surface-plane knuckles,
to be produced.
[0006] During the 1980's, an alternate means for providing a TAD fabric with the equivalent
of wicker-basket-like cavities was developed. Procter & Gamble's
U.S. Patents Nos. 4,528,239;
4,529,480; and
4,637,859 to Trokhan, which are among the earliest U.S. patent documents on these means, show a TAD belt
comprising a foraminous woven element, that is, a woven base fabric, having a coating
of a polymeric resin material in preselected areas. More specifically, the polymeric
resin material provides the TAD belt with a macroscopically monoplanar, patterned,
continuous network surface which serves to define within the TAD belt a plurality
of discrete, isolated deflection conduits or holes, rather than wicker-basket-like
cavities. To produce the TAD belt, the foraminous woven element is thoroughly coated
with a liquid photosensitive resin to a controlled thickness above its upper surface,
and a mask or a negative having opaque and transparent regions which define a desired
pattern is brought into contact with the surface of the liquid photosensitive resin,
and the resin is exposed to actinic radiation through the mask. The radiation, typically
in the ultraviolet (UV) portion of the spectrum, cures the portions of the resin exposed
through the mask, but does not cure the portions shadowed by the mask. The uncured
resin is subsequently removed by washing to leave behind the foraminous woven element
with a coating in the desired pattern formed by the cured resin.
[0007] The seminal U.S. patent disclosing this method is Procter & Gamble's
U.S. Patent No. 4,514,345 to Johnson et al. In addition to disclosing the method for making the TAD belt described in the preceding
paragraph, this patent also shows a belt in which the polymeric resin material forms
a plurality of discrete protuberances on its surface. That is to say, the pattern
is the reverse of a continuous network having holes. Instead, the pattern is of discrete
areas which are occluded or blocked by the polymeric resin material in an otherwise
open foraminous woven element. Belts of this kind may be used in the forming section
of a bulk tissue machine to form embryonic paper webs having discrete regions of relatively
low basis weight in a continuous background of relatively high basis weight, as shown,
for example, in Procter & Gamble's
U.S. Patent No. 5,277,761 to Van Phan et al. Belts of this kind may also be used to manufacture nonwoven articles and fabrics,
which have discrete regions in which the density of fibers is less than that in adjacent
regions, by processes such as hydroentanglement, melt-blown, spun-bond and air-laid.
Also in
U.S. Patent Nos. 6,080,691 and
6,120,642 to Kimberly-Clark there is disclosed a papermaking fabric for producing a soft, bulky tissue web wherein
the web contact surface is a three dimensional porous nonwoven material. This material
may be in the form of fiberous mats or web, extruded network or foams. Attachment
of the porous nonwoven material can be by lamination, extrusion, adhesives, melt bonding,
entanglement, welding, needling, nesting or layering.
[0008] In addition to discrete (non-continuous) and continuous networks of polymeric resin
material on the foraminous woven element, the method disclosed in
U.S. Patent No. 4,514,345 to Johnson et al. may also be used to manufacture belts having semicontinuous networks of polymeric
resin material. For example, Procter & Gamble's
U.S. Patent No. 5,714,041 to Ayers et al. shows a belt, useful as a TAD fabric, having a framework of protuberances arranged
in a semicontinuous pattern to provide a semicontinuous pattern of deflection conduits.
By "semicontinuous" is meant that each protuberance extends substantially throughout
the belt in an essentially linear fashion, and that each protuberance is spaced apart
from adjacent protuberances- As such, the protuberances may be lines which are generally
straight, parallel and equally spaced from one another, or may be in the shape of
zigzags which are generally parallel and equally spaced from one another.
[0009] In some bulk tissue applications, press fabrics having a continuous, semicontinuous
or discrete network of polymeric resin material on their paper-contacting surfaces
are used. By "press fabric" is meant a fabric normally used on the press section of
a paper machine and comprising a base fabric or other support structure and one or
more layers of staple fiber material attached to at least one side thereof. For example,
Procter & Gamble's
U.S. Patent No. 5.556,509 to Trokhan et al. shows "press fabrics" having continuous and discrete networks of polymeric material
on their paper-contacting surfaces and used to make bulk tissue products.
[0010] The method disclosed in
U.S. Patent No. 4,514,345, and the refinements thereto disclosed in subsequent Procter & Gamble U.S. patents,
are quite elaborate and time-consuming. A more direct approach for providing a forming,
press or TAD fabric, or a fabric used in the manufacture of nonwoven articles and
fabrics by processes such as hydroentanglement, melt-blown, spun-bond and air-laid,
with a coating of a polymeric resin material in the form of a continuous, semicontinuous
or discrete network has long been sought in the industries concerned. A further method
of applying a resinous framework onto the surface of an paper marking belt is disclosed
in
U.S. Patent No . 6,358,594. The present invention satisfies this long-felt need.
SUMMARY OF THE INVENTION
[0011] Accordingly, the present invention is a method according to claim 1 for manufacturing
a belt and a belt for use in the production of bulk tissue and towel, and of nonwoven
articles and fabrics. The invention comprises a first step of providing a base substrate
for the belt.
[0012] Polymeric resin material is then deposited onto the base substrate in a precise predetermined
pattern, which predetermined pattern is to be imparted onto products manufactured
with the belt. The polymeric resin material penetrates into the base substrate and,
when desired, forms a layer of desired thickness thereover. The polymeric resin material
is deposited in droplets having an average diameter of 10µ (10 microns) or more, and
is then set or fixed by appropriate means. Subsequently, the coating of polymeric
resin material may optionally be abraded to provide it with a uniform thickness and
a smooth, macroscopically monoplanar surface.
[0013] The present invention will now be described in more complete detail, with frequent
reference being made to the figures identified below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014]
Figure 1 is a schematic view of an apparatus used to manufacture papermaker's belts
according to the method of the present invention;
Figure 2 is a plan view of a completed belt as it would appear upon exit from the
apparatus of Figure 1;
Figure 3 is a cross-sectional view taken as indicated in Figure 2;
Figure 4 is a plan view of a second embodiment of the belt;
Figure 5 is a plan view of a third embodiment of the belt;
Figure 6 is a plan view of a belt of the variety shown in Figure 2 having an additional
pattern superimposed upon a pattern of discrete passages; and
Figure 7 is a perspective view ot a variety of representative shapes of the deposited
material.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The method for fabricating a belt in accordance with the present invention begins
with the provision of a base structure or substrate. Typically, the base substrate
is a fabric woven from monofilament yarns. More broadly, however, the base substrate
may be a woven, nonwoven or knitted fabric comprising yarns of any of the varieties
used in the production of paper machine clothing or of belts used to manufacture nonwoven
articles and fabrics, such as monofilament, plied monofilament, multifilament and
plied multifilament yarns. These yarns may be metal or may be obtained by extrusion
from any of the polymeric resin materials used for this purpose by those of ordinary
skill in the art and/or any combination thereof. Accordingly, resins from the families
of polyamide, polyester, polyurethane, polyaramid, polyolefin and other resins may
be used. Other material suitable for the purpose may also be used.
[0016] Alternatively, the base substrate may be composed of mesh fabrics, such as those
shown in commonly assigned
U.S. Patent No. 4,427,734 to Johnson, the teachings of which are incorporated herein by reference. The base substrate
may further be a spiral-link belt of the variety shown in many U.S. patents, such
as
U.S. Patent No. 4,567,077 to Gauthier, the teachings of which are also incorporated herein by reference.
[0017] Moreover, the base substrate may be produced by spirally winding a strip of woven,
nonwoven, knitted or mesh fabric in accordance with the methods shown in commonly
assigned
U. S. Patent No. 5,360,656 to Rexfelt et al., the teachings of which are incorporated herein by reference. The base substrate
may accordingly comprise a spirally wound strip, wherein each spiral turn is joined
to the next by a continuous seam making the base substrate endless in a longitudinal
direction.
[0018] The above should not be considered to be the only possible forms for the base substrate.
Any of the varieties of base substrate used by those of ordinary skill in the paper
machine clothing and related arts may Alternatively be used.
[0019] Once the base substrate has been provided, one or more layers of staple fiber batt
may optionally be attached to one or both of its two sides by methods well known to
those of ordinary skill in the art. Perhaps the best known and most commonly used
method is that of needling, wherein the individual staple fibers in the batt are driven
into the base structure by a plurality of reciprocating barbed needles. Alternatively,
the individual staple fibers may be attached to the base substrate by hydroentangling,
wherein fine high-pressure jets of water perform the same function as the above-mentioned
reciprocating barbed needles. It will be recognized that, once staple fiber batt has
been attached to the base substrate by either of these or other methods known by those
of ordinary skill in the art, one would have a structure identical to that of a press
fabric of the variety generally used to dewater a wet paper web in the press section
of a paper machine.
[0020] Alternatively still, the base substrate may be a structure which has been rendered
impermeable to fluids, such as air and water, with a coating of a polymeric resin
material, which at least partially impregnates the structure and which may form a
layer of a desired thickness on one of its two sides. An impermeable base substrate
may be used in the present invention in the manufacture of an embossing belt of the
variety shown in
U.S. Patent No. 6,340,413, the teachings of which are incorporated herein by reference. The embossing belt
disclosed therein is essentially impermeable and comprises a rear layer and a web-contacting
layer, which has a large number of uniformly distributed depressions and, positioned
therebetween, surface portions for forming a corresponding relief pattern in a fibrous
web passing through a press section of a paper machine. The embossing belt also transfers
the embossed fibrous web to the dryer section of the paper machine.
[0021] Furthermore, structures of this type, whether permeable or not, can have a random
surface topography. This topography can be repeated within a structure, or obviously,
repeated in a subsequent structure produced for the same paper, tissue or nonwoven
production machine. Fabrics of this type are taught in
U.S. Patent Nos. 6,080,691 and
6,120,642, the disclosures of which are incorporated herein by reference.
[0022] The belts manufactured in accordance with the present invention may be used on the
forming, press or through air-drying sections of a paper machine, especially those
producing tissue or towel products, or on a machine used to manufacture nonwoven articles
and fabrics by processes such as hydroentanglement, melt-blown, spun-bond and air-laid.
Those having a needled batt-on-base substrate are most suitable for use on a press
section, while those lacking staple fiber batt may find use on any of these sections
or machines. In some cases, it may be necessary to apply an initial layer or additional
batt to the structure after application of the resin. In such cases the patterned
resin may lie below a layer of batt fibers.
[0023] Once the base substrate, with or without the addition of staple fiber batt material,
has been provided, it is mounted on the apparatus 10 shown schematically in Figure
1. It should be understood that the base substrate may be either endless or seamable
into endless form during installation on a paper machine. As such, the base substrate
12 shown in Figure 1 should be understood to be a relatively short portion of the
entire length of the base substrate 12. Where the base substrate 12 is endless, it
would most practically be mounted about a pair of rolls, not illustrated in the figure
but most familiar to those of ordinary skill in the paper machine clothing arts. In
such a situation, apparatus 10 would be disposed on one of the two runs, most conveniently
the top run, of the base substrate 12 between the two rolls. Whether endless or not,
however, the base substrate 12 is preferably placed under an appropriate degree of
tension during the process. Moreover, to prevent sagging, the base substrate 12 may
be supported from below by a horizontal support member as it moves through apparatus
10.
[0024] Referring now more specifically to Figure 1, where the base substrate 12 is indicated
as moving in an upward direction through the apparatus 10 as the method of the present
invention is being practiced, apparatus 10 comprises a sequence of several stations
through which the base substrate 12 may pass incrementally as a belt is being manufactured
therefrom.
[0025] In the first station, the polymer deposition station 14, a piezojet array 16 mounted
on transverse rails 18,20 and translatable thereon in a direction transverse to that
of the motion of the base substrate 12 through the apparatus 10, as well as therebetween
in a direction parallel to that of the motion of the base substrate 12, is used to
deposit polymeric in repeated steps to build up the desired amount of resin material
onto the base substrate 12 in a predetermined pattern.
[0026] Alternatively, other means for depositing the small droplets required for the practice
of the present invention, as will be discussed below, may be known to those of ordinary
skill in the art or may be developed in the future, and may be used in the practice
of the present invention. In addition, the deposit of the material need not only be
traversing the movement of the base substrate but can be parallel to such movement,
spiral to such movement or in any other manner suitable for the purpose.
[0027] The polymeric resin material penetrates into the base substrate, and, when desired,
forms a layer of a desired thickness thereover, in the predetermined pattern. That
pattern may be a continuous network extending substantially throughout both dimensions
of the surface of the base substrate 12 and defining an array of discrete open areas
which are to be the ultimate locations of a corresponding array of discrete holes
or passages for fluid through the belt being manufactured from the base substrate
12, or on the surface of the belt of the base substrate 12. It is also envisioned
for some applications that the belt need not be permeable. In this case the substrate
may be a support base already impregnated with a resin, and having no fluid permeability
or the substrate may be an extruded polymer film or even a metal band. The discrete
open areas may form outlines or other representations of familiar objects, such as
clouds, flowers, swans or leaves, or of corporate or company logos, which are to appear
in the desired array on the product to be manufactured on the belt. Moreover, the
array of outlines may be superimposed on a background array of smaller discrete holes.
[0028] Alternatively, the polymeric resin material may be deposited in a semicontinuous
network, for example, a semicontinuous pattern extending substantially throughout
the base substrate 12 in an essentially linear fashion, thereby forming lines which
are generally parallel and equally spaced from one another. Such lines may be either
straight, curved or zigzag. More generally, a semicontinuous network comprises straight
or curved lines, or lines having both straight and curved segments, which are spaced
apart from one another and do not cross one another.
[0029] Alternatively still, the polymeric resin material may be deposited in an array of
discrete locations. It should be appreciated that the polymeric resin material may
be deposited in a manner forming an outline or other representation of a familiar
object, such as a cloud, flower, swan or leaf, or of a corporate or company logo,
which is to appear in the desired array on the product to be manufactured on the belt.
Moreover, the array of outlines may be superimposed on a background array of smaller
discrete locations on which the polymeric resin material is deposited.
[0030] In each case, the polymeric resin material impregnates and blocks the passages through
the base substrate 12, and, when desired, rises to a predetermined height above the
surface of the base substrate 12
, at the locations where it is deposited. As such, the polymeric resin material could
ultimately reside entirely within the surface plane of the base substrate 12, even
with the surface plane of the base substrate 12, or above the surface plane of the
base substrate 12.
[0031] The piezojet array 16 comprises at least one but preferably a plurality of individual
computer-controlled piezojets, each functioning as a pump whose active component is
a piezoelectric element. As a practical matter, an array of up to 256 piezo jets or
more may be utilized, if the technology permits. The active component is a crystal
or ceramic which is physically deformed by an applied electric signal. This deformation
enables the crystal or ceramic to function as a pump, which physically ejects a drop
of a liquid material each time an appropriate electric signal is received. As such,
this method of using piezojets to supply drops of a desired material repeatedly so
as to build up the desired amount of material in the desired shape in response to
computer-controlled electric signals is commonly referred to as a "drop-on-demand"
method.
[0032] The degree of precision of the jet in depositing the material will depend upon the
dimensions and shape of the structure being formed. The type of jet used and the viscosity
of the material being applied will also impact the precision of the jet selected.
[0033] Referring again to Figure 1, the piezojet array 16, starting from an edge of the
base substrate 12, or, preferably, from a reference thread extending lengthwise therein,
translates lengthwise and widthwise across the base substrate 12, while the base substrate
12 is at rest, deposits the polymeric resin material in the form of extremely small
droplets having a nominal diameter of 10µ (10 microns) or more such as, of 50µ (50
microns), or 100µ (100 microns), in one of the above-described patterns. The translation
of the piezojet array 16 lengthwise and widthwise relative to the base substrate 12,
and the deposition of droplets of the polymeric resin material from each piezojet
in the array 16, are controlled by computer in a controlled manner to produce the
predetermined pattern of the polymeric resin material in a controlled geometry in
three planes length, width and depth or height (x, y, z dimensions or direction) within,
and, when desired, on the base substrate 12. One or more passes over the base substrate
12 may be made by piezojet array 16 to deposit the desired amount of material and
to create the desired shape. In this regard, the deposits can take any number of shapes
as illustrated generally in Figure 7. The shapes can be square, round conical, rectangular,
oval, trapezoidal etc. with a thicker base tapering upward. Depending upon the design
chosen, the amount of material deposited can be layered in decreasing fashion as the
jet repeatedly passes over the deposit area.
[0034] In the present invention, in which a piezojet array is used to deposit polymeric
resin material onto or within selected areas of the surface of the base substrate
12, the choice of polymeric resin material is limited by the requirement that its
viscosity be 100 cps (100 centipoise) or less at the time of delivery, that is, when
the polymeric resin material is in the nozzle of a piezojet ready for deposition,
so that the individual piezojets can provide the polymeric resin material at a constant
drop delivery rate. In this regard, the viscosity of the polymeric resin material
at the point of delivery in conjunction with the jet size is important in deferring
the size and shape of the droplets formed on the base substrate 12 and in time the
resolution of the pattern ultimately achieved. Another requirement limiting the choice
of polymeric resin material is that it must partially set during its fall, as a drop,
from a piezojet to the base substrate 12, or after it lands on the base substrate
12, to prevent the polymeric resin material from flowing and to maintain control over
the polymeric resin material to ensure its deposition in the desired pattern. Suitable
polymeric resin materials which meet these criteria are:
- 1. Hot melts and moisture-cured hot melts;
- 2. Two-part reactive systems based on urethanes and epoxies;
- 3. Photopolymer compositions consisting of reactive acrylated monomers and acrylated
oligomers derived from urethanes, polyesters, polyethers, and silicones; and
- 4. Aqueous-based latexes and dispersions and particle-filled formulations including
acrylics and polyurethanes.
[0035] As noted above, the piezojet array 16 is capable of supplying the polymeric resin
material in the form of extremely small droplets having an average diameter of 10µ
(10 microns) or more, so long as its viscosity is less than 100 cps (100 centipoise)
or less at the time of delivery. Moreover, the piezojet array 16 can deposit the polymeric
resin material with great precision one layer at a time, making it unnecessary to
grind the surface of a layer formed thereby on the base substrate 12 to achieve a
uniform thickness, and enables one of ordinary skill in the art to control the z-direction
geometry of the polymeric resin material. That is to say, the piezojet array 16 can
deposit the polymeric resin material with such precision that the surface will be
monoplanar without having to be ground or, alternatively, that the surface will have
some predetermined three-dimensional structure.
[0036] That is to say by depositing the droplets in a repeating pattern, that being by layering
one droplet on the top of the next, the height or z-direction of the polymeric resin
material on the base substrate 12 is controlled and may be uniform, varied or otherwise
adjusted as desired. Further, some of the individual piezojets in the piezojet array
may be used to deposit one polymeric resin material, while others may be used to deposit
a different polymeric resin material, to produce a surface having microregions of
more than one type of polymeric resin material. It is understood that one or more
passes of jet array 16 may be required to apply the required polymer resin material
onto the base substrate 12.
[0037] Moreover, in an alternative embodiment of the present invention, the piezojet array
16 may include one or more bulk jets, which deposit polymeric resin material onto
the base substrate 12, at a rate greater than that at which it can be deposited by
piezojets. The choice of the polymeric resin material to be deposited by the bulk
jets is not governed by the viscosity requirement for the polymeric resin material
being deposited by the piezojets. As such, a wider variety of polymeric resin materials,
such as polyurethane and photosensitive resins, may be deposited using the bulk jets.
In practice, the bulk jets are used to deposit the "bulk" of the polymeric resin material
onto the base substrate 12 at crude resolution, while the piezojets are used to refine
the details of the pattern produced by the polymeric resin material on the base substrate
12 at higher resolution. The bulk jets may operate prior to or simultaneously with
the piezojets. In this manner, the entire process of providing a base substrate 12
with a pattern of a polymeric resin material can proceed more quickly and efficiently.
[0038] It should be understood that the polymeric resin material needs to be fixed on or
within the base substrate 12 following its deposition thereon. The means by which
the polymeric resin material is set or fixed depends on its own physical and/or chemical
requirements. Photopolymers are cured with light, whereas hot-melt materials are set
by cooling. Aqueous based latexes and dispersions are dried and then cured with heat,
and reactive systems are cured by heat. Accordingly, the polymeric resin materials
may be set by curing, cooling, drying or any combination thereof.
[0039] The proper fixing of the polymeric resin material is required to control its penetration
into and distribution within the base substrate 12, that is, to control and confine
the material within the desired volume of the base substrate 12. Such control is important
below the surface plane of the base substrate 12 to prevent wicking and spreading.
Such control may be exercised, for example, by maintaining the base substrate 12 at
a temperature which will cause the polymeric resin material to set quickly upon contact.
Control may also be exercised by using such materials having well-known or well-defined
curing or reaction times on base substrates having a degree of openness such that
the polymeric resin material will set before it has time to spread beyond the desired
volume of the base substrate 12.
[0040] When the pattern has been completed in a band between the transverse rails 18,20
across the base substrate 12, the base substrate 12 is advanced lengthwise an amount
equal to the width of the band, and the procedure described above is repeated to produce
the predetermined pattern in a new band adjacent to that previously completed. In
this repetitive manner, the entire base substrate 12 can be provided with the predetermined
pattern. Note the pattern can be random, a repeating random pattern on a base substrate
or such patterns that are repeatable from belt to belt for quality control.
[0041] Alternatively, the piezojet array 16, again starting from an edge of the base substrate
12, or, preferably, from a reference thread extending lengthwise therein, is kept
in a fixed position relative to the transverse rails 18,20, while the base substrate
12 moves beneath it, to deposit the polymeric resin material in the desired pattern
in a lengthwise strip around the base substrate 12. Upon completion of the lengthwise
strip, the piezojet array 16 is moved widthwise on transverse rails 18,20 an amount
equal to the width of the lengthwise strip, and the procedure described above is repeated
to produce the predetermined pattern in a new lengthwise strip adjacent to that previously
completed. In this repetitive manner, the entire base substrate 12 can be provided
with the predetermined pattern.
[0042] The surface is usually the contacting surface with the paper, tissue, towel or nonwoven
producted to be produced. It is envisioned that some products/processes will require
this resin to be primarily on the nonproduct contact surface. In this case fluid flow
or mechanical pressure differences that occur when the belt and the produced products
are in contact will still cause local density or texture differences.
[0043] At one end of the transverse rails 18,20, a jet check station 22 is provided for
testing the flow of polymeric resin material from each jet. There, the jets can be
purged and cleaned to restore operation automatically to any malfunctioning jet unit.
[0044] In the second station, the imaging/repair station 24, transverse rails 26,28 support
a digital imaging camera 30, which is translatable across the width of base substrate
12, and a repair-jet array 32, which is translatable both across the width of the
base substrate 12 and lengthwise relative thereto between transverse rails 26,28,
while the base substrate 12 is at rest.
[0045] The digital imaging camera 30 views the deposited polymeric resin material to locate
any faulty or missing discrete elements or similar irregularities in a semicontinuous
or continuous pattern produced thereby on the base substrate 12. Comparisons between
the actual and desired patterns are made by a fast pattern recognizer (FPR) processor
operating in conjunction with the digital imaging camera 30. The FPR processor signals
the repairjet array 32 to deposit additional polymeric resin material onto the elements
detected to be faulty or missing. As before, at one end of the transverse rails 26,28,
a repair-jet check station 34 is provided for testing the flow of material from each
repair jet. There, each repair jet can be purged and cleaned to restore operation
automatically to any malfunctioning repair jet unit.
[0046] In the third station, the optional setting station 36, transverse rails 38,40 support
a setting device 42, which may be required to set the polymeric resin material being
used. The setting device 42 may be a heat source, for example, an infrared, hot air,
microwave or laser source; cold air; or an ultraviolet or visible light source, the
choice being governed by the requirements of the polymeric resin material being used.
[0047] Finally, the fourth and last station is the optional grinding station 44, where an
appropriate abrasive is used to provide any polymeric resin material above the surface
plane of the base substrate 12 with a uniform thickness and a smooth, macroscopically
monoplanar surface. The optional grinding station 44 may comprise a roll having an
abrasive surface, and another roll or backing surface on the other side of the base
substrate 12 to ensure that the grinding will result in a uniform thickness and a
smooth, macroscopically monoplanar surface.
[0048] As an example, reference is now made to Figure 2, which is a plan view of a completed
belt 50 as it would appear upon exit from optional setting station 36 and the optional
grinding station 44 of apparatus 10. The belt 50 has a coating of polymeric resin
material 52 except for a plurality of discrete holes 54 in a predetermined pattern.
A portion of a permeable base substrate 12, which comprises a system of machine-direction
(MD) yarns 56 interwoven with a system of cross-machine-direction (CD) yarns 58, is
visible in each of the discrete holes 54.
[0049] Figure 3 is a cross-sectional view of a completed belt 50 taken as indicated in Figure
2. In this example, polymeric resin material 52 forms a layer of a desired thickness
over the base substrate 12, except for the areas represented by the discrete passages
64.
[0050] Alternative embodiments of the belt are shown in Figures 4 and 5. Figure 4 is a plan
view of a belt 60 whose base substrate 12 has a plurality of discrete areas 62 of
polymeric resin material in a predetermined array. Such a belt 60 may be used in the
forming section of a papermaking machine.
[0051] Figure 5 is a plan view of a belt 70 having a semicontinuous network of polymeric
resin material on its surface. The semicontinuous network extends substantially throughout
the belt 70 in an essentially linear fashion. Each portion 72 of the semicontinuous
network extends in a substantially straight line, which may zigzag to some extent,
parallel to others making up the network. Each portion 72 is of polymeric resin material.
[0052] Figure 6 is a plan view of a belt 80 of the variety shown in Figure 2 having an additional
pattern superimposed upon a pattern of discrete passages 82. The additional pattern
84, which is a logo, but which may also be a familiar object, may also be repeated
in a desired array on the belt 80. A portion of the permeable base substrate 12 is
visible in each of the discrete passages 82, as well as in the additional pattern
84.
[0053] In an alternate embodiment of the present invention, the polymer deposition station
14, the imaging/repair station 24, and the setting station 36 may be adapted to produce
a belt from the base substrate 12 in a spiral technique, rather than indexing in the
cross-machine direction as described above. In a spiral technique, the polymer deposition
station 14, the imaging/repair station 24, and the setting station 36 start at one
edge of the base substrate 12, for example, the left-hand edge in Figure 1, and are
gradually moved across the base substrate 12, as the base substrate 12 moves in the
direction indicated in Figure 1. The rates at which the stations 14,24,36 and the
base substrate 12 are moved are set so that the pattern desired in the finished belt
is spiralled onto the base substrate 12 in a continuous manner. In this alternative,
the polymeric resin material deposited by the polymer deposition station 14 and imaging/repair
station 24 may be partially set or fixed as each spiral passes beneath the setting
device 42, and completely set when the entire base substrate 12 has been processed
through the apparatus 10.
[0054] Alternatively, where the piezojet array 16 deposits the polymeric resin material
in the desired pattern in a lengthwise strip around the base substrate 12, the imaging/repair
station 24 and the setting station 36 may also be kept in a fixed position aligned
with the piezojet array 16, while the base substrate 12 moves beneath them, so that
the pattern desired in the finished belt is applied to a lengthwise strip around the
base substrate 12. Upon completion of the lengthwise strip, the piezojet array 16,
the imaging/repair station 24 and the setting station 36 are moved widthwise an amount
equal to the width of the lengthwise strip, and the procedure is repeated for a new
lengthwise strip adjacent to that previously completed. In this repetitive manner
the entire base structure 12 can be completely coated.
[0055] Furthermore, the entire apparatus can remain in a fixed position with the material
processed. It should be noted that the material need not be a full width belt but
can be a strip of material such as that disclosed in
U.S. Patent No. 5,360,656 to Rexfelt, the disclosure of which is incorporated herein by reference, and subsequently formed
into a full width belt. The strip can be unwound and wound up on a set of rolls after
fully processing. These rolls of belting materials can be stored and can then be used
to form an endless full width structure using, for example, the teachings of the immediately
aforementioned patent.
[0056] Modifications to the above would be obvious to those of ordinary skill in the art,
but would not bring the invention so modified beyond the scope of the appended claims.
In particular, while piezojets are disclosed above as being used to deposit the polymeric
resin material in preselected locations on the base substrate, other means for depositing
droplets thereof in the size range desired may be known to those of ordinary skill
in the art or may be developed in the future, and such other means may be used in
the practice of the present invention. For example, in processes requiring a relatively
larger scale pattern such that the final elements such as round hemispheres, a relatively
large, even a single resin deposition nozzle can comprise the entire jet array. The
use of such means would not bring the invention, if practiced therewith, beyond the
scope of the appended claims.
1. A method for manufacturing a belt for use in the production of bulk tissue and towel,
and of nonwoven articles and fabrics, said method comprising the steps of;
a) providing a base substrate (12) for the belt;
b) depositing polymeric resin material (52) onto said base substrate (12) in a controlled
manner so as to control the x, y, z dimensions of the material deposited to create
a predetermined pattern of deposits, wherein this step comprises building up each
deposit using droplets of polymeric resin material; and
c) at least partially setting said polymeric resin material.
2. A method as claimed in claim 1 wherein said droplets have an average diameter of 10µ
(10 microns) or more.
3. A method as claimed in claim 1 wherein steps b) and c) are performed sequentially
on successive bands extending widthwise across said base substrate.
4. A method as claimed in claim 1 wherein steps b) and c) are performed sequentially
on successive strips extending lengthwise around said base substrate.
5. A method as claimed in claim 1 wherein steps b) and c) are performed spirally around
said base substrate.
6. A method as claimed in one of claims 1 to 5 wherein, in step b), said predetermined
pattern comprises a plurality of discrete locations (62) set forth in a predetermined
array.
7. A method as claimed in one of claims 1 to 5 wherein, in step b), said predetermined
pattern comprises a continuous network defining a plurality of discrete open ares
in a predetermined array.
8. A method as claimed in one of claims 1 to 5 wherein, in step b), said predetermined
patterns comprises a semicontinuous network extending substantially throughout said
base substrate.
9. A method as claimed in one of previous claims wherein, in step b), said polymeric
resin material, penetrates into said base substrate.
10. A method as claimed in one of previous claims wherein, in step b), said polymeric
resin material forms a uniform or random pattern layer of desired thickness over said
base substrate.
11. A method as claimed in one of previous claims wherein, in step b), said polymeric
resin material is deposited by a piezo-jet means.
12. A method as claimed in one of previous claims wherein, in step b), said polymeric
resin material is deposited by a piezo-jet array (16) comprising a plurality of individual
computer-controlled piezo-jets.
13. A method as claimed in one of previous claims further comprising, between steps b)
and c), the steps of:
i) checking the actual pattern of said polymeric resin material to measure conformity
to said predetermined pattern to measure conformity to said predetermined pattern;
and
ii) repairing said actual pattern of said polymeric resin material to eliminate departures
from said predetermined pattern.
14. A method as claimed in claim 13 wherein said checking step is performed by a fast
pattern recognizer (FPR) processor operating in conjunction with a digital imaging
camera.
15. A method as claimed in claim 14 wherein said repairing step is performed by a repair-jet
array coupled to said FPR processor.
16. A method as claimed in one of previous claims, wherein said polymeric resin material
is selected from the group consisting of:
1. hot melts and moisture-cured hot melts;
2. two-part reactive systems based on urethanes and epoxies;
3. photopolymer compositions consisting of reactive acrylated monomers and acrylated
oligomers derived from urethanes, polyesters, polyethers, and silicones; and
4. aqueous-based latexes and dispersions and particle-filled formulations including
acrylics and polyurethanes.
17. A method as claimed in one of previous claims wherein said curing step is performed
by exposing said polymeric resin material to a heat source.
18. A method as claimed in one of claims 1 to 16 wherein said curing step is performed
by exposing said polymeric resin material to cold air.
19. A method as claimed in one of claims 1 to 16 wherein said curing step is performed
by exposing said polymeric resin material to actinic radiation.
20. A method as claimed in one of previous claims wherein a first polymeric resin material
is deposited and a second polymeric resin is deposited which is different from the
first polymeric resin material.
21. A method as claimed in claim 10 wherein said polymeric resin material is deposited
in a uniformly thick layer having a monoplanar surface.
22. A method as claimed 10 wherein said polymeric resin material is deposited in a nonuniformly
thick layer having a surface with a three-dimensional structure.
23. A method as claimed in one of previous claims further comprising the step of depositing
the polymeric resin material onto said base substrate in said predetermined pattern
with a bulk jet to accelerate the manufacture of said belt.
24. A method as claimed in claim 23 wherein said depositing step is carried out prior
to step b).
25. A method as claimed in claim 23 wherein said depositing step is carried out simultaneously
with step b) .
26. A method as claimed in one of previous claims further comprising the step of abrading
said polymeric resin material deposited on said base substrate to provide said polymeric
resin material with a uniform thickness and a smooth, macroscopically monoplanar surface.
27. A method as claimed in one of previous claims which includes the step of providing
a base substrate taken from the group consisting essentially of woven, nonwoven, spiral
formed, spiral-link, knitted, mesh or strips of material which are ultimately wound
to form a belt having a width greater than a width of the strips.
28. A method as claimed in one of previous claims wherein the base substrate comprises
yarns taken from the group including monofilament, plied monofilament, multifilament
and plied multifilament.
29. A method as claimed in claim 28 wherein such yarns comprise metal, polyamide, polyester,
polyurethane, polyaramid or polyolefin.
1. Verfahren zur Herstellung eines Bandes zur Verwendung bei der Fertigung von Papier-Tissue
und -Handtüchern sowie von Vliesstoffen und Vliesstoffartikeln, mit den folgenden
Verfahrensschritten:
a) Bereitstellung eines Grundsubstrats (12) für das Band;
b) Ablagerung von Material eines polymeren Kunstharzes (52) auf die genannte Grundstruktur
(12) in geregelter Weise derart, dass die Dimensionen x, y und z des abgelagerten
Materials geregelt werden, um ein vorbestimmtes Ablagerungsmuster zu erzeugen, wobei
dieser Schritt umfasst, jede Ablagerung aus Tröpfchen des polymeren Kunstharzmaterials
aufzubauen; und
c) mindestens teilweises Aushärten des genannten polymeren Kunstharzmaterials.
2. Verfahren nach Anspruch 1, bei dem die genannten Tröpfchen einen mittleren Durchmesser
von 10µ (10 Mikron) oder mehr besitzen.
3. Verfahren nach Anspruch 1, bei dem die Schritte b) und c) nacheinander an aufeinanderfolgenden
Bändern ausgeführt werden, die sich quer über das genannte Grundsubstrat erstrecken.
4. Verfahren nach Anspruch 1, bei dem die Schritte b) und c) nacheinander an aufeinanderfolgenden
Streifen ausgeführt werden, die sich der Länge nach um das genannte Grundsubstrat
erstrecken.
5. Verfahren nach Anspruch 1, bei dem die Verfahrensschritte b) und c) spiralförmig um
das genannte Grundsubstrat ausgeführt werden.
6. Verfahren nach einem der Ansprüche 1 bis 5, bei dem im Schritt b) das vorbestimmte
Muster aus vielen getrennten Bereichen (62) besteht, die in einer vorbestimmten Reihe
angeordnet sind.
7. Verfahren nach einem der Ansprüche 1 bis 5, bei dem das genannte vorbestimmte Muster
im Schritt b) ein kontinuierliches Netz bildet, das eine Vielzahl von diskreten offenen
Bereichen in einer vorbestimmten Anordnung definiert.
8. Verfahren nach einem der Ansprüche 1 bis 5, bei dem im Schritt b) das genannte vorbestimmte
Muster ein halbkontinuierliches Netz bildet, das sich praktisch über das gesamte Grundsubstrat
erstreckt.
9. Verfahren nach einem der vorstehenden Ansprüche, bei dem das genannte polymere Kunstharzmaterial
im Schritt b) in das genannte Grundsubstrat eintritt.
10. Verfahren nach einem der vorstehenden Ansprüche, bei dem das genannte polymere Kunstharzmaterial
im Schritt b) ein gleichförmiges oder zufälliges Muster in Form einer Schicht mit
der gewünschten Dicke auf dem genannten Grundsubstrat bildet.
11. Verfahren nach einem der vorstehenden Ansprüche, bei dem das genannte polymere Kunstharzmaterial
im Schritt b) mit Hilfe von Piezostrahlmitteln abgelagert wird.
12. Verfahren nach einem der vorstehenden Ansprüche, bei dem das genannte polymere Kunstharzmaterial
im Schritt b) mit Hilfe einer Serie von Piezostrahlern (16) abgelagert wird, welche
mehrere einzelne Piezostrahler aufweist, die vom Computer gesteuert werden.
13. Verfahren nach einem der vorstehenden Ansprüche, bei dem zwischen den Schritten b)
und c) folgende zusätzliche Schritte ausgeführt werden:
i) Überprüfung des vorliegenden Musters des genannten polymeren Kunstharzmaterials
zwecks Messung der Übereinstimmung mit dem vorbestimmten Muster; und
(ii) Reparatur des genannten vorliegenden Musters des genannten polymeren Kunstharzmaterials
zwecks Eliminierung der Abweichungen vom genannten vorbestimmten Muster.
14. Verfahren nach Anspruch 13, bei dem der genannte Überprüfungsschritt von einem schnellen
Mustererkennungsprozessor (FPR) ausgeführt wird, der mit einer digitalen Bilderzeugungskamera
zusammenwirkt.
15. Verfahren nach Anspruch 14, bei dem der genannte Reparaturschritt durch eine Serie
von Reparaturstrahlern ausgeführt wird, die mit dem genannten FPR-Prozessor gekoppelt
sind.
16. Verfahren nach einem der vorstehenden Ansprüche, bei dem das genannte polymere Kunstharzmaterial
aus einer der folgenden Gruppen ausgesucht wird:
1. Heissschmelzmassen und feuchtigkeitshärtende Heissschmelzmassen;
2. reaktive Zweikomponentensysteme auf der Grundlage von Urethanen und Epoxiharzen;
3. Photopolymer-Zusammensetzungen aus reaktiven Acrylmonomeren und Acryloligomeren,
abgeleitet von Urethanen, Polyestern, Polyethern und Silikonen; und
4. wässrige Latexe und Dispersionen sowie mit Teilchen gefüllte Formulierungen einschliesslich
Acrylharzen und Polyurethanen.
17. Verfahren nach einem der vorstehenden Ansprüche, bei dem der genannte Härtungsschritt
dadurch ausgeführt wird, dass man das genannte polymere Kunstharzmaterial einer Wärmequelle
aussetzt.
18. Verfahren nach einem der Ansprüche 1 bis 16, bei dem der genannte Härtungsschritt
dadurch ausgeführt wird, dass man das genannte polymere Kunstharzmaterial kalter Luft aussetzt.
19. Verfahren nach einem der Ansprüche 1 bis 16, bei dem der genannte Härtungsschritt
dadurch ausgeführt wird, dass man das genannte polymere Kunstharzmaterial einer chemisch
wirksamen Strahlung aussetzt.
20. Verfahren nach einem der vorstehenden Ansprüche, bei dem ein erstes polymeres Kunstharzmaterial
abgelagert und dann ein zweites polymeres Kunstharzmaterial abgelagert wird, welches
sich vom ersten polymeren Kunstharzmaterial unterscheidet.
21. Verfahren nach Anspruch 10, bei dem das genannte polymere Kunstharzmaterial in einer
gleichförmig dicken Schicht mit einer monoplanaren Oberfläche abgeschieden wird.
22. Verfahren nach Anspruch 10, bei dem das genannte polymere Kunstharzmaterial in Form
einer ungleichförmig dicken Schicht abgelagert wird.
23. Verfahren nach einem der vorstehenden Ansprüche, welches als zusätzlichen Schritt
die Ablagerung des polymeren Kunstharzmaterials auf dem genannten Grundsubstrat in
Form des genannten vorbestimmten Musters mit Hilfe eines Massenstrahlers abgelagert
wird, um die Herstellung des genannten Bandes zu beschleunigen.
24. Verfahren nach Anspruch 23, bei dem der genannte Ablagerungsschritt vor dem Schritt
b) ausgeführt wird.
25. Verfahren nach Anspruch 23, bei dem der genannte Ablagerungsschritt gleichzeitig mit
Schritt b) ausgeführt wird.
26. Verfahren nach einem der vorstehenden Ansprüche, welches weiterhin als zusätzlichen
Schritt ein Abtragen des genannten polymeren Kunstharzmaterials, welches auf dem genannten
Grundsubstrat abgelagert ist, umfasst, um das genannte polymere Kunstharzmaterial
mit einer gleichförmigen Dicke und einer glatten, makroskopisch monoplanaren Oberfläche
zu versehen.
27. Verfahren nach einem der vorstehenden Ansprüche, bei dem der Schritt, bei dem ein
Grundsubstrat bereitgestellt wird, darin besteht, dass dieses Grundsubstrat aus der
Gruppe entnommen wird, die im Wesentlichen aus gewebtem, nicht gewebtem, spiralerzeugtem,
spiralverbundenem, gestricktem Textilmaterial oder aus Maschenware oder Streifen eines
Materials besteht, wobei die Streifen schliesslich aufgewickelt werden, um ein Band
zu erzeugen, dessen Breite grösser ist als die Breite der einzelnen Streifen.
28. Verfahren nach einem der vorstehenden Ansprüche, bei dem das Grundsubstrat Garne aus
der Gruppe der Monofilamente, mehrlagigen Monofilamente, Multifilamente und mehrlagigen
Multifilamente enthält.
29. Verfahren nach Anspruch 28, bei dem derartige Garne aus einem Metall, aus Polyamid,
Polyester, Polyurethan, Polyaramid oder Polyolefin bestehen.
1. Procédé de fabrication d'une courroie pour une utilisation dans la fabrication de
papier tissu et de serviettes ainsi que d'articles et de matières textiles non tissées,
ledit procédé comportant les étapes suivantes :
a) la mise à disposition d'un substrat de base (12) pour la courroie ;
b) le dépôt d'un matériaux de résine polymère (52) sur ledit substrat de base (12)
de manière contrôlée afin de pouvoir commander les dimensions x, y et z de la matière
déposée et de créer un dessin prédéterminé de dépôts, où cet étape comprend la construction
de chaque dépôt en utilisant des gouttelettes d'un matériaux de résine polymère ;
et
c) le durcissement au moins partiel dudit matériau de résine polymère.
2. Procédé selon la revendication 1, dans lequel lesdites gouttelettes présentent un
diamètre moyen de 10µ (10 micromètres) ou davantage.
3. Procédé selon la revendication 1, dans lequel les étapes b) et c) sont exécutées de
manière séquentielle sur des bandes successives s'étendant selon la largeur à travers
ledit substrat de base.
4. Procédé selon la revendication 1, dans lequel les étapes b) et c) sont exécutées de
manière séquentielle sur des bandes successives s'étendant dans le sens de la longueur
autour dudit substrat de base.
5. Procédé selon la revendication 1, dans lequel les étapes b) et c) sont exécutées en
spirale autour dudit substrat de base.
6. Procédé selon l'une des revendications 1 à 5, dans lequel ledit dessin prédéterminé
dans l'étape b) comprend une pluralité d'endroits discrets (62) arrangés selon un
ordre prédéterminé.
7. Procédé selon l'une des revendications 1 à 5, dans lequel ledit dessin prédéterminé
dans l'étape b) comprend un réseau continu définissant une pluralité d'aires ouvertes
discrètes selon un arrangement prédéterminé.
8. Procédé selon l'une des revendications 1 à 5, dans lequel ledit dessin prédéterminé
dans l'étape b) comprend un réseau semi-continu s'étendant substantiellement sur tout
le substrat de base.
9. Procédé selon l'une des revendications précédentes, dans lequel, dans l'étape b),
ledit matériau de résine polymère pénètre dans ledit substrat de base.
10. Procédé selon l'une des revendications précédentes, dans lequel ledit matériau de
résine polymère forme dans l'étape b) sur ledit substrat de base une couche de dessin
uniforme ou aléatoire ayant une épaisseur désirée.
11. Procédé selon l'une des revendications précédentes, dans lequel ledit matériau de
résine polymère est déposé dans l'étape b) au moyen d'un jet piézoélectrique.
12. Procédé selon l'une des revendications précédentes, dans lequel ledit matériau de
résine polymère est déposé dans l'étape b) au moyen d'une série de jets piézoélectriques
(16) comprenant une pluralité de jets piézoélectriques individuels pilotés par ordinateur.
13. Procédé selon l'une des revendications précédentes, comprenant de plus les étapes
suivantes entre les étapes b) et c) :
i) la vérification du dessin réel dudit matériau de résine polymère afin de mesurer
la conformité avec ledit dessin prédéterminé ; et
ii) la réparation dudit dessin réel dudit matériau de résine polymère afin d'éliminer
des divergences par rapport audit dessin prédéterminé.
14. Procédé selon la revendication 13, dans lequel ladite étape de vérification est exécutée
par un processeur de reconnaissance rapide de dessins (FPR) fonctionnant en coopération
avec une caméra à images numériques.
15. Procédé selon la revendication 14, dans lequel ladite étape de réparation est exécutée
par une série de jets de réparation couplés audit processeur FPR.
16. Procédé selon l'une des revendications précédentes, dans lequel ledit matériau de
résine polymère est choisi dans le groupe formé par :
1. des compositions thermofusibles et des compositions thermofusibles à durcissement
par humidité ;
2. des systèmes réactifs à deux composants à base d'uréthannes et d'époxydes ;
3. des compositions photopolymères constituées de monomères acryliques et d'oligomères
acryliques réactifs, dérivés d'uréthannes, de polyesters, de polyéthers et de silicones-;
et
4. des latex et dispersions aqueux et des formulations chargées de particules y compris
des acryliques et des polyuréthannes.
17. Procédé selon l'une des revendications précédentes, dans lequel ladite étape de durcissement
est exécutée en exposant ledit matériau de résine polymère à une source de chaleur.
18. Procédé selon l'une des revendications 1 à 16, dans lequel ladite étape de durcissement
est exécutée en exposant ledit matériau de résine polymère à l'air froid.
19. Procédé selon l'une des revendications 1 à 16, dans lequel ladite étape de durcissement
est exécutée en exposant ledit matériau de résine polymère à une radiation actinique.
20. Procédé selon l'une des revendications précédentes, dans lequel un premier matériau
de résine polymère est déposé, et un deuxième matériau de résine polymère est déposé
qui est différent du premier matériau de résine polymère.
21. Procédé selon la revendication 10, dans lequel ledit matériau de résine polymère est
déposé sous forme d'une couche d'épaisseur uniforme présentant une surface monoplane.
22. Procédé selon la revendication 10, dans lequel ledit matériau de résine polymère est
déposé sous forme d'une couche d'épaisseur non uniforme présentant une surface avec
une structure tridimensionnelle.
23. Procédé selon l'une des revendications précédentes, comprenant de plus une étape de
dépôt de matériau de résine polymère sur ledit substrat de base selon ledit dessin
prédéterminé au moyen d'un jet massique afin d'accélérer la fabrication de ladite
courroie.
24. Procédé selon la revendication 23, dans lequel ladite étape de dépôt est exécutée
avant l'étape b).
25. Procédé selon la revendication 23, dans lequel ladite étape de dépôt est exécutée
en même temps que l'étape b).
26. Procédé selon l'une des revendications précédentes, comprenant de plus l'étape d'érosion
de ladite résine polymère déposée sur ledit substrat de base afin de munir ladite
résine polymère d'une épaisseur uniforme et d'une surface lisse et macroscopiquement
monoplane.
27. Procédé selon l'une des revendications précédentes, qui comprend l'étape de la mise
à disposition d'un substrat de base choisi dans le groupe comprenant essentiellement
des matières textiles tissées, non tissées, formées en spirales, liées par spirales,
tricotées ou extrudées en mailles, ou des bandes de matière textile qui sont finalement
enroulées pour former une courroie de largeur plus grande que la largeur des bandes.
28. Procédé selon l'une des revendications précédentes, dans lequel le substrat de base
comprend des fils choisis dans le groupe comprenant des monofilaments, des monofilaments
multiples, des multifilaments et des multifilaments multiples.
29. Procédé selon la revendication 28, dans lequel ces fils comprennent du métal, du polyamide,
du polyester, du polyuréthanne, du polyaramide ou du polyoléfine.