[0001] The present invention relates to a support device for printing plates of the type
as recited in the preamble of Claim 1.
[0002] In particular, the invention relates to a specific support device suitable for use
in the production of plates for chalcography, that is to say plates on which the design
to be printed is etched or engraved or otherwise cut.
[0003] As is known in the prior art, in order to create such plates a cast must first be
made to obtain the negative of the design to be printed and this cast must then be
coated with layers of silver and nickel.
[0004] In detail, first the cast is created by etching a base plate, usually made of polyamide
or Kapton
®, for example using laser technology, to produce a negative of the images and the
words to be printed.
[0005] When this has been done, the cast is placed in a device in which a chemical deposition
process is performed in order to create a first layer, usually in silver, to coat
the surface of the cast with said negative of the image.
[0006] At this point, the plate is placed in a second device in which a metallic nickel
layer is deposited over the layer of silver, by means of a galvanic deposition process.
[0007] The nickel layer is then separated from the silver layer and from the cast, accreted
and, lastly, coated with a layer of material with a high surface hardness, usually
hard chromium.
[0009] The prior art solution mentioned above has several significant drawbacks.
[0010] A first drawback lies in the fact that the galvanic processes involve the use of
galvanic baths which are associated with problems in terms of the safety of the operator
and disposal of the industrial waste that is generated, which is particularly difficult
and expensive and has a significant environmental impact.
[0011] A further drawback of the printing plates produced in this way consists of the fact
that they are not of a uniform thickness over the entire surface of the plate.
[0012] The drawbacks described above have been overcome by replacing the galvanic processes
with high-vacuum processes.
[0013] However, such high-vacuum processes have some additional drawbacks.
[0014] They are performed with the plates rotating or translating. The plates therefore
have to be supported to prevent them from assuming incorrect positions and, in particular,
to ensure the maintenance of the correct position and, thus, a uniform and optimal
deposition of the layer of nickel.
[0015] A further drawback lies in the difficulty of creating a support that can be secured
to the plates without covering the print design and so is able to guarantee its correct
coating.
[0016] For these reasons, said support is extremely important.
[0017] In this situation the technical purpose of the present invention is to devise a support
device for printing plates that substantially overcomes the drawbacks mentioned above
and, in particular, permits the coating of printing plates using the high-vacuum deposition
method.
[0018] Within the scope of said technical purpose an important aim of the invention is to
provide a support device that makes it possible to have printing plates comprising
layers created using high-vacuum processes.
[0019] The technical purpose and specified aims are achieved with a support device for printing
plates as claimed in the appended Claim 1.
[0020] Preferred embodiments are described in the dependent claims.
[0021] The characteristics and advantages of the invention are clearly evident from the
following detailed description of a preferred embodiment thereof, with reference to
the accompanying drawings, in which:
Fig. 1 shows a support device according to the invention;
Fig. 2 shows a detail of the support device;
Fig. 3a shows a plate to be arranged on the support device according to the invention;
Fig. 3b shows a plate to be arranged on the support device; and
Fig. 4 illustrates a portion of the support device according to the invention.
[0022] With reference to said drawings, reference numeral 1 globally denotes the support
device according to the invention.
[0023] It is suitable to be used to create printing plates
10 and, in detail, plates for security printing comprising a base layer
11 having an etched surface
11a comprising etchings or the like to be printed such as, for instance, those on banknotes,
stamps, documents or other security printing products; and an outer coating
12 made of a hard-wearing material and, preferably of a material selected from among
chromium, zirconium or titanium or the nitrides or carbonitrides thereof, and covering
said etched surface 11 a so as to define the printing surface
10a substantially reproducing the etchings present on the etched surface 11 a.
[0024] The support device 1 comprises a support
20 defining a main axis of extension
20a preferably parallel to the gravitational gradient, and a substantially prismatic
overall profile; attachments
30 suitable to engage with the opposite rims
11b of the base layer 11 surrounding the etched surface 11a; stops
40 suitable to prevent a relative movement between the base layer 11 and the attachments
30; and hooks
50 suitable to releasably secure the attachments 30 to the support 20 in correspondence
with the overall profile.
[0025] The support 20 comprises at least one base plate
21 and, preferably, two base plates 21 substantially perpendicular to the axis 20a and
defining the overall profile of the device 1; and at least one support body
22 suitable to substantially position itself between the plates 21 so as to define a
mutual distance between the base plates 21 substantially at least equal to and, appropriately,
substantially more than one of the dimensions of the etched surface 11 a, i.e. of
the width or length of said etched surface 11 a.
[0026] Additionally, the support 20 may comprise at least one intermediate plate
23 arranged between the base plates 21 and suitable to increase the structural rigidity
of the support device 1 and to define additional anchoring points of the plates 10
to the support 20.
[0027] Advantageously, the plates 21 and 23 are substantially circular in shape with their
axis substantially coinciding with the axis 20a so as to define a substantially prismatic,
circular-based overall profile, i.e. a cylinder-shaped profile of the support device
1.
[0028] The support body 22 has an axis of extension that substantially coincides with the
axis 20a and has a smaller cross-section than the plates 21 and 23 so that practically
the entire perimeter of the plates 21 and 23 is overhanging in relation to said support
body 22.
[0029] In particular, it comprises profiles
22a having an axis of extension substantially parallel to the axis 20a and arranged along
the perimeter of a circumference centred on the axis 20a having a radius smaller than
that of the plates 21 and 23.
[0030] Arranged along the perimeter of the plates 21, the support device 1 has at least
a pair of attachments 30 suitable to allow the etched surface 11 a to be arranged
substantially parallel to the axis 20a and, in particular, to allow the tips of the
surface 11 a to be arranged substantially at the same distance from the main axis
of extension 20a.
[0031] Appropriately, the support device 1 comprises a plurality of pairs of attachments
30 suitable to permit a plurality of base layers 11 to be attached to the support
device 1 by arranging their etched surfaces 11 a substantially parallel and at the
same distance from the main axis of extension 20a.
[0032] Each attachment 30 comprises at least one slit 31 suitable to internally house at
least a portion of a rim 11 b and extending substantially parallel to the axis 20a.
[0033] Preferably, the attachments 30 consist of rods characterised by a length of not less
than the length of the rims 11 b and provided with slits 31 extending at least the
length of said rims 11 b.
[0034] Joined to the attachments 30, the support device 1 is provided with the stops 40
suitable to prevent a relative movement between the base layer 11 and the attachments
30.
[0035] For that purpose, the stops 40 are suitable to engage with the base layer 11 in correspondence
with the rims 11 b and the slits 31 so as not to interfere with the deposit of particles
and, thus, the creation of the outer coating 12 on at least the etched portion of
surface 11 a. Said stops 40 comprise screws engaged in holes obtained in proximity
to the rims 11 b and along the slits and/or stop elements suitable to prevent the
relative sliding between the slits 31 and the base layer 11 along at least the axis
20a.
[0036] Lastly, to enable the base layer 11 to be secured to the support device 1 in a convenient
and practical manner, the device 1 is provided with hooks 50 suitable to releasably
connect, preferably by means of a snap engagement, the attachments 30 to the support
20 in correspondence with the overall profile.
[0037] In particular, said hooks 50 are arranged in correspondence with the ends of the
attachments 30 and permit said attachments to be secured in correspondence with the
profile of the base plates 21.
[0038] They thus comprise at least a first body integral with the attachment 30 in correspondence
with one end thereof and defining a seat
51 suitable to internally house and, thus, to snap engage with an edging 20b obtained
in correspondence with the outer perimeter of the support 20 and, in particular, of
the two plates 21.
[0039] The edgings 20b protrude from the plates 21 in a direction substantially parallel
to the preferred axis of extension 20a so as to permit the seat 51 to engage with
it by means of a translation substantially parallel to the main axis of extension
20a and, in detail, to engage with it substantially due to the force of gravity.
[0040] The edgings 20b conveniently protrude in the same direction so as to permit their
simultaneous engagement with the seats 51.
[0041] The support device 1 is suitable for use in an innovative high-vacuum deposit device
capable of creating a coating 12 with a thickness of substantially less than 10 µm
by means of a high-vacuum deposition process.
[0042] Preferably, the deposit device is suitable for creating the coating 12 by means of
a high-vacuum deposition process using the PVD or PE CVD or other similar technique.
[0043] Said device comprises, in addition to the support device 1, a container 100 defining
said inner chamber suitable to contain the support device 1; a delivery apparatus
suitable to deliver into the inner chamber and, thus, deposit on the printing plates
10, the particles, preferably of a material chosen from among chromium, zirconium
or titanium or the nitrides or carbonitrides thereof, which form the coating 12; an
apparatus for creating a vacuum, for example a vacuum pump, suitable to substantially
create a vacuum in the inner chamber; a movement device suitable to move and, in particular,
to rotate the support device 1 and the plates 10 along an axis of rotation so as to
guarantee the uniform distribution of the particles and, thus, the formation of a
substantially uniform coating 12. Said axis of rotation is preferably substantially
parallel to the main axis of extension 20a.
[0044] The use of a support device and the functioning of a high-vacuum deposit device described
above in a structural sense, are as follows.
[0045] First, a plurality of nickel base layers 11 are prepared, by performing the galvanic
electroforming process described.
[0046] The base layers 11 are then secured to the support device 1.
[0047] In detail, opposite rims of the layer 11 are inserted in the slits 31 and then secured
to the attachments 30 by means of the stops 40.
[0048] The base layer is then bent so as to obtain a curvature that is substantially the
same as that of the base plates 21 and so that the etched surface 11 a defines the
outer surface of the curvature.
[0049] Next, the layer 11 is secured to the support device 1 along the outer perimeter of
said support device 1 inserting portions of the edging 20b in the seats 51 so that
the etched surface 11 a is facing the opposite direction to the axis 20a and substantially
parallel to said axis 20a thus substantially defining the overall profile of the support
device 1.
[0050] Once this has been done, the support device 1 is inserted inside the chamber and
arranged so that the axis 20a substantially coincides with the axis of rotation of
the unit.
[0051] The vacuum apparatus substantially creates a vacuum in the inner chamber; the movement
unit turns the support device 1 and the bodies 11 about the preferred axis of extension
20a and, at the same time, the delivery apparatus feeds the particles that form the
coating 12 into the chamber 110a and thus deposits them on the etched surfaces 11
a.
[0052] When the deposition of the outer coating 12 is complete, the plates 10 are removed
from the device 1 and are now ready to be used for printing.
[0053] The invention achieves some important advantages.
[0054] A first important advantage achieved by using the innovative support device 1 consists
in the fact that a high-vacuum process is used to create the printing plates, thus
eliminating the need for galvanic deposition processes and so reducing the costs of
production of the plates 10 and eliminating the problems of safety and of having to
deal with the industrial waste products typically associated with such prior art processes,
making it possible to produce a plate with a low environmental impact and respecting
the environment.
[0055] Another important advantage lies in the fact that with the support device 1, the
use of a high-vacuum deposition process to create a coating 12 makes it possible to
obtain plates 10 with a highly uniform thickness.
[0056] Said advantages are primarily due to the fact that the support device 1 only engages
with the plates 11 in correspondence with the rims 11 b and so does not interfere
with the deposition of the coating 12 along the etched surface 11 a and, thus, guarantees
the formation of said coating 12 along the entire printing surface 10a.
[0057] Another advantage lies in the fact that the coating 12 is characterised by an extremely
uniform thickness and, thus, by a uniform resistance to wear and physical and mechanical
properties.
[0058] This advantage is also due to the fact that with the device 1, the surfaces 11 a
can be arranged substantially parallel to and, in particular, at an equal distance
from the axis 11 and, more in particular, from the axis of rotation defined by the
movement unit so as to guarantee the uniformity of the coating 12.
[0059] Another no less important advantage lies in the fact that the hooks 50, by means
of a snap engagement and, in particular, an engagement between the attachments 30
and support 20 substantially due to the force of gravity, make it possible to guarantee
an extremely practical and stable assembly of the support device 1.
1. Support device (1) for printing plates (10) comprising a base layer (11) defining
an etched surface (11a) and rims (11b) surrounding said etched surface (11 a); said
support (1) being suitable to be used for the high vacuum deposit of an outer coating
(12) on said etched surface (11a) and being characterised in that it comprises: a support (20) defining a main extension axis (20a) a substantially
prismatic overall profile, an edging (20b) of said overall profile protruding in a
direction substantially parallel to said main extension axis (20a); attachments (30)
comprising slits (31) suitable to contain at least a portion of opposite rims (11b)
and having main directions of extension substantially parallel to said main extension
axis (20a); stops (40) suitable to prevent a relative movement between said base layer
(11) and said attachments (30); and hooks (50) comprising at least one seat (51) integral
with said attachments (30) suitable to snap engage to said edging (20b).
2. Support device (1) as claimed in claim 1, in which said attachments (30) are suitable
to constrain said base layer (11) to said support (20) placing said etched surface
(11 a) substantially parallel to said main extension axis (20a).
3. Support device (1) as claimed in one or more of the previous claims, in which said
support (20) defines said substantially prismatic, circular-based, overall profile.
4. Support device (1) as claimed in the preceding claim, in which said attachments (30)
are suitable to constrain said base layer (11) to said support (20) placing the tips
of said etched surface (11a) substantially at the same distance from said main extension
axis (20a).
5. Support device (1) as claimed in one or more of the previous claims, in which said
support (20) comprises two base plates (21) substantially perpendicular to said main
extension axis (20a) and defining said overall profile; and at least one support body
(22) suitable to substantially position itself between said plates (21) substantially
equal to a dimension of said etched surface (11 a).
6. Support device (1) as claimed in the preceding claim, in which said base plates (21)
and said support body (22) have a main extension axis substantially coinciding with
said main extension axis (20a); and in which said base plate (21) has a greater cross-section
than said support body (22) so that the perimeter of said plates (21) is overhanging
in relation to said support body (22).
7. Support device (1) as claimed in one or more of the claims 6-7, in which said edging
(20b) protrudes from said base plates (21) along the perimeter of said base plates
(21).
1. Trägervorrichtung (1) für Druckplatten (10), die eine Basisschicht (11), die eine
geprägte Oberfläche (11a) definiert, und Ränder (11b), die die genannte geprägte Oberfläche
umgeben, umfasst; wobei die genannte Trägervorrichtung (1) geeignet ist, für die Aufbringung
einer Außenbeschichtung (12) in Hochvakuum auf die genannte geprägte Oberfläche (11a)
verwendet zu werden und dadurch gekennzeichnet ist, eine Stütze (20), die eine vorrangige Verlaufsachse (20a) definiert, ein im
Wesentlichen prismatisches Formprofil und eine im Wesentlichen in paralleler Richtung
vorstehende Umrandung (20b) des genannten Formprofils zu umfassen; Anbringungen (30),
die Spalten (31) umfassen, die geeignet sind, wenigsten einen Teil gegenüberliegender
Ränder (11 b) zu enthalten und vorrangig parallel zu der genannten vorrangigen Verlaufsachse
(20a) parallele Verlaufsrichtungen aufweisen; Feststeller (40), die geeignet sind,
eine relative Bewegung zwischen der genannten Basisschicht (11) und den genannten
Anbringungen (30) zu verhindern; und Befestigungen (50), die wenigstens einen Sitz
(51) umfassen, der mit den genannten Anbringungen (30) fest verbunden und geeignet
ist, durch Steckverbindung in die genannte Umrandung (20b) einzugreifen.
2. Trägervorrichtung (1) nach Anspruch 1, bei der die genannten Anbringungen (30) geeignet
sind, die genannte Basisschicht (11) an der genannten Stütze (20) zu befestigen, da
die genannte geprägte Oberfläche (11a) im Wesentlichen zu der genannten vorrangigen
Verlaufsachse (20a) parallel ist.
3. Trägervorrichtung (1) nach einem oder mehreren der vorangegangenen Ansprüche, bei
der die genannte Stütze (20) das genannte, im Wesentlichen prismatische Formprofil
mit kreisförmiger Basis definiert.
4. Trägervorrichtung (1) nach dem vorangegangenen Anspruch, bei der die genannten Anbringungen
(30) geeignet sind, die genannte Basisschicht (11) an der genannten Stütze (20) zu
befestigen, indem die Punkte der genannten geprägten Oberfläche (11a) im Wesentlichen
im gleichen Abstand von der genannten vorrangigen Verlaufsachse (20a) angeordnet werden.
5. Trägervorrichtung (1) nach einem oder mehreren der vorangegangenen Ansprüche, bei
der die genannte Stütze (20) zwei im Wesentlichen zu der genannten vorrangigen Verlaufsachse
senkrechte Basisplatten (21) umfasst und das genannte Formprofil definiert; und wenigstens
einen Stützkörper (22), der geeignet ist, im Wesentlichen zwischen die genannten Platten
(21) gesetzt zu werden, die im Wesentlichen einer Dimension der genannten geprägten
Oberfläche (11a) entsprechen.
6. Trägervorrichtung (1) nach dem vorangegangenen Anspruch, bei der die genannten Basisplatten
(21) und der genannte Stützkörper (22) eine im Wesentlichen mit der vorrangigen Verlaufsachse
(20a) übereinstimmende Ausdehnungsachse aufweisen; und bei der die genannten Basisplatten
(21) einen größeren Querschnitt als der genannte Stützkörper (22) aufweisen, so dass
der Umfang der genannten Platten (21) im Vergleich zu dem genannten Stützkörper (22)
übersteht.
7. Trägervorrichtung (1) nach einem oder mehreren der Ansprüche 6-7, bei der die genannte
Umrandung (20b) von den Basisplatten (21) entlang des Umfangs der genannten Basisplatten
(21) vorsteht.
1. Dispositif de support (1) pour plaques d'impression (10) comprenant une couche de
base (11) définissant une surface gravée (11 a) et des bords (11 b) contournant ladite
surface gravée (11a) ; ledit support (1) étant apte à être utilisé pour le dépôt sous
haut vide d'un revêtement extérieur (12) sur ladite surface gravée (11a) et étant
caractérisé en ce qu'il comprend un soutien (20) définissant un axe prédominant de développement (20a)
un profil d'encombrement essentiellement prismatique (20b) dudit profil d'encombrement
saillant par rapport à la direction essentiellement parallèle audit axe prédominant
de développement (20a) ; attaches (30) comprenant des fentes (31) aptes à contenir
au moins une partie des bords (11b) opposés et ayant directions d'extensions prédominantes
essentiellement parallèles audit axe prédominant de développement (20a) ; arrêts (40)
aptes à empêcher un mouvement relatifs entre ladite couche de base (11) et lesdites
attaches (30) ; et crochets (50) comprenant au moins un siège (51) solidaire desdites
attaches (30) apte à s'engager par encastrement dans ladite bordure (20b).
2. Dispositif de support (1) selon la revendication 1, dans lequel lesdites attaches
(30) sont aptes à assujettir ladite couche de base (11) audit soutien (20) disposant
ladite surface gravée (11a) essentiellement parallèle audit axe prédominant de développement
(20a).
3. Dispositif de support (1) selon une ou plusieurs des revendications précédentes, dans
lequel ledit support (20) définit ledit profil d'encombrement essentiellement prismatique
à base circulaire.
4. Dispositif de support (1) selon la revendication précédente, dans lequel, lesdites
attaches (30) sont aptes à assujettir ladite couche de base (11) audit soutien (20)
disposant les points de ladite surface gravée (11a) essentiellement à la même distance
dudit axe prédominant de développement (20a).
5. Dispositif de support (1) selon une ou plusieurs des revendications précédentes, dans
lequel ledit soutien (20) comprend deux plaques de base (21) essentiellement perpendiculaires
audit axe prédominant de développement (20a) et définissant ledit profil d'encombrement
; et au moins un corps de soutien (22) apte à s'interposer essentiellement entre lesdites
plaques (21) essentiellement égal à une dimension de ladite surface gravée (11 a).
6. Dispositif de support (1) selon la revendication précédente, dans lequel lesdites
plaques de base (21) et ledit corps de soutien (22) présentent un axe d'extension
essentiellement coïncidant avec ledit axe prédominant de développement (20a) ; et
dans lequel lesdites plaques de base (21) présentent une section supérieure audit
corps de soutien (22) de sorte que le périmètre desdites plaques (21) soit en saillie
par rapport audit corps de soutien (22).
7. Dispositif de support (1) selon une ou plusieurs des revendications 6-7, dans lequel
ladite bordure (20b) est en saillie par rapport auxdites plaques de base (21) le long
du périmètre desdites plaques de base (21).