Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F35/00—Cleaning arrangements or devices
  • B41F35/06—Cleaning arrangements or devices for offset cylinders
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
  • B41J2/0057—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material where an intermediate transfer member receives the ink before transferring it on the printing material

Definitions

• Device for controlling the deposition of material (s) for an offset printing system and method for implementing the device
• the present invention relates to the field of offset printing systems and more particularly the field of control devices of the material deposition step (s) for these printing systems.
• Offset printing systems allow the implementation of a major process among the various current printing processes. This process stems directly from the prior lithography printing process, with the notable difference that it allows a greater flexibility of operation by allowing printing of several thousand copies on a wide variety of substrates (paper, cardboard polymeric .. .)
• Lithographic printing processes are flat printing processes. We consider here that the offset printing processes use bendable printing plates. The principle of offset printing is based on the principle of water-fat repulsion by creating an emulsion between an aqueous wetting solution and a fatty ink successively deposited on an engraved copper and aluminum offset plate. The engraved plate then comprises the image to be printed by the offset method.
• the aqueous solution during the wetting step is deposited to adhere to the aluminum parts of the surface of the plate while, during inking, the fatty ink is repelled by the water on the copper parts of the plate.
• the ink thus deposited on the offset plate is then transmitted to an intermediate printing roller called blanket before being transferred to the final substrate.
• Such a printing technique has been proven in terms of quality and allows the production of a large quantity of printed substrate without altering the finish.
• this technique has the disadvantage of having an image to be printed which is dependent on the etching of the offset plate.
• this technique makes it possible to limit the wear of the printing over time, it nevertheless implies a considerable cost when a piece machinery must be replaced.
• the object of the present invention is to overcome this drawback of the prior art by proposing a device capable of implementing an impression which retains the advantages and properties of the offset process but which also makes it possible to gain in speed of change of image and / or reduce the costs of production and manufacturing of machinery for printing a new image.
• a deposition control device (s) for offset printing system comprising at least:
• an offset plate for receiving at least one material for transferring the material or materials onto a substrate
• the deposition means comprising at least one head group projecting at least one fountain solution and at least one head group projecting at least one colored material,
• the coating of the offset plate comprises a mesh defined by a plurality of hydrophilic and lipophilic unit surfaces capable of receiving a controlled deposition of material (s), each of these hydrophilic and lipophilic unit surfaces being separated from its direct neighbors by at least one hydrophobic and lipophobic peripheral surface.
• each group of heads comprises at least one deposition head of material (s), each head comprising at least one nozzle individually controlled by a computer system and a digital file, each head being intended to project at least one material on the surface of the offset plate so that all projections produce a image and / or text on the surface of the offset plate corresponding to the image and / or the text of the digital file for the colored material heads and the negative of the image for the fountain solution heads.
• the group or groups of fountain solution heads comprises at least one deposition head of a fountain solution comprising at least one nozzle projecting a fountain solution material, the group or groups of heads of colored materials. comprising at least one fundamental color deposit head each having at least one nozzle projecting a material of a different fundamental color.
• the group or groups of fountain solution heads comprising at least one deposition head comprising at least one nozzle projecting a fountain solution material, the group or groups of colored material heads comprising at least one fountain solution head. deposit comprising at least one nozzle per fundamental color, each of the nozzles of the depositing head projecting a material of a different fundamental color.
• the mesh comprises unitary surfaces of rectangular shape arranged relative to each other so as to make a grid of the surface.
• the mesh comprises hexagonal-shaped unitary surfaces arranged relative to each other so as to produce a mesh of honeycombs of the surface.
• the value of the width of a lipophobic and hydrophobic peripheral surface corresponds to a value between 5% and 50% of the width of a lipophilic and hydrophilic unit surface.
• the width of a unit surface capable of receiving the material is at least equal to or greater than 35 ⁇ . According to another feature, the width of a unit surface capable of receiving the wetting liquid or the colored material is at least equal to 5 ⁇ .
• the offset plate is set in motion by displacement means, the displacement means setting the offset plate incrementally in motion between each deposit of material (s) deposited by the where the nozzles in the center. at least one unitary surface, each increment corresponding to the size of at least one half-cell.
• the invention also relates to a printing system on a substrate characterized in that it incorporates a material deposition control device (s) according to the invention.
• the printing system further comprises a drying device for drying the material or materials deposited on the substrate.
• the substrate passes between the deposition control device (s) and a counterpressure cylinder.
• the system comprises at least one blanket for each offset plate, the substrate passing between the counterpressure cylinder (s) and the blanket (s).
• the invention also relates to a printing process using at least one deposit control device (s) according to the invention, comprising successively:
• the step of controlled deposition of material (s) comprises a deposition of material (s) on at least one predefined point of the surface of the offset plate corresponding to the position of a point of the image to be defined or the negative of the image.
• the step of controlled deposition of material (s) comprises:
• the step of controlled deposition of material (s) comprises:
• a step of controlled deposition of a fountain solution material by the one or more nozzles projecting a fountain solution material - a step of controlled deposition of material of each fundamental color by the nozzles projecting a different fundamental color material.
• the method comprises:
• the method comprises a step of drying by a drying device of the material or materials reported on the substrate.
• FIG. 1 represents a perspective view of an exemplary embodiment of a device for controlling the deposition of material (s) according to the invention
• FIG. 2 represents a profile view of the material deposition control device of the invention
• FIG. 2bis is a diagram of a detail of FIG. 2 according to an embodiment of the surface of the offset plate of the deposition control device of the material (s) of the invention, FIG. according to another embodiment of the surface of the offset plate of the deposit control device of the material (s) of the invention,
• FIG. 4 shows a perspective view of the printing system implementing the deposit control device material (s) of the invention.
• the term "material” will denote any type of material that can be emitted by jet, for example and without limitation, colors of any kind, varnishes, coating products, adhesives, coating solutions. wetting ...
• the wetting solution may be water.
• Color materials or colored materials may be, for example, inks of different colors, for example, fundamental colors such as cyan, yellow and magenta.
• substrate (4) should be understood in a broad sense, ie as any type of flexible or rigid substrate adapted to work with the printing system.
• substrates can thus be of cellulosic types (paper, cardboard, wood), composites, textile or synthetic materials in continuous mode or sheet-fed mode, the thickness of which may vary from a few tens of micrometers to several centimeters.
• the present invention makes it possible to preserve the principle of the offset printing process by relying on the use of a universal offset plate (2) whose surface is arranged to receive and maintain the deposition of a layer of material (s). ) according to a predefined arrangement.
• the arrangement of the layer of material on the surface of the plate is defined by controlled deposition and not only by the etching of the surface of the offset plate (2).
• the device (0) for controlling the deposition of material (s) is achieved through the combination of two elements which allow on the one hand the precise deposition of the material or materials on the surface of the (2) and on the other hand maintaining the arrangement of the material or materials deposited on the offset plate (2).
• the device (0) for controlling the deposition of material (s) of the invention is thus constructed with a deposition means (1) adapted to precisely manage the deposition of the material or materials on the surface of the offset plate (2). ).
• This deposition means (1) of the material or materials is achieved, for example, by at least one group of heads comprising at least one head having at least one nozzle (100) ejection.
• the nozzle (100) for ejection may be, for example, a thermal nozzle where is used the phenomenon of vaporization of the material or materials which are then deposited on the surface of the offset plate (2). The material or materials are thus precisely deposited on the offset plate (2).
• Each nozzle (100) is individually controlled by a computer system and a digital file.
• Each head is thus intended to project at least one material onto the surface of the offset plate (2) so that all the projections produce an image and / or a text on the surface of the offset plate (2) corresponding to the image and / or text of the digital file.
• the deposition means (1) comprises at least one group of wetting solution heads comprising at least one deposition head of a fountain solution. Each head has at least one nozzle projecting a fountain solution material.
• the deposition means (1) may further comprise at least one group of colored material heads comprising at least one deposition head per fundamental color. Each head each has at least one nozzle projecting a material of a different fundamental color.
• the deposition means (1) comprises at least one fountain solution head group comprising at least one deposition head of a fountain solution. Each depositing head comprises at least one nozzle projecting a material of fountain solution.
• the deposition means (1) may comprise at least one group of colored material heads comprising at least one deposition head. Each head has at least one nozzle for each fundamental color. Each of the nozzles of the depositing head projects a material of a different fundamental color.
• the material deposition control device may be associated, for example, at least one means (6) for cleaning the offset plate (2).
• This cleaning means (6) may be intended to recover the residues of projected materials remaining on the surface of the offset plate (2) and which have not been transferred to the substrate (4).
• This means (6) of cleaning thus allows a permanent cleaning of the surface of the offset plate before projection of new jets of materials.
• This cleaning means (6) may, for example, be composed of a set of doctor blades and rollers. Some rollers and scrapers may be in direct contact with the surface of the offset plate (2).
• the cleaning device (3) may also comprise a blowing means such as a blower.
• this assembly may be supplemented, for example, and in a nonlimiting manner, by means of adding water, or solvents, by means of heating or cooling means.
• the means (6) for cleaning the deposition control device (s) may comprise a combination of these various devices so as to be versatile and able to clean different type of material residue.
• the device (0) for controlling the deposition of material (s) also rests on the surface of the offset plate (2) which is arranged to allow the precise retention of the material or materials deposited on the surface of the plate. This maintenance of accuracy is provided by an offset plate (2) which has a universal surface adapted to interact with the deposited material or by reversibly fixing it.
• the offset plate (2) has a surface comprising a mesh of a plurality of hydrophilic and lipophilic unit areas (9), each of these unit areas being surrounded by a hydrophobic and lipophobic boundary (8) or peripheral surface which separates it from its direct neighbors also hydrophilic and lipophilic.
• the surface of the offset plate (2) produces a mesh of hydrophilic and lipophilic unit zones (9) identical to each other and where each of them produces the smallest unit area capable of receiving a controlled deposition of material (s).
• Each of these hydrophilic (9) and lipophilic unit areas has a necessary and sufficient surface to receive at least one dose of material (s) deposited (s) by the deposition means (1).
• the nozzle or nozzles (100) of the deposition means (1) is positioned facing a hydrophilic or lipophilic surface, by example by being centered on this surface, to project the material or materials.
• the group or groups of heads of the deposition means (1) of the material or materials is mounted movably along an axis (1a) to allow lateral movements in a width of the offset plate (2).
• the axis that carries the group or groups of heads of the depositing means (1) can be movable to allow movement of the or groups of heads in a length of the offset plate (2). This variant embodiment will be preferred when the offset plate (2) is constructed in the form of a planar structure.
• the displacement of the group or groups of heads in the width of the offset plate (2) can be replaced by the use of a plurality of heads arranged side by side and positioned so as to be in position. vis-à-vis a unit area (9) deposition respective.
• the displacement of the group or groups of heads in the length of the offset plate (2) can be replaced by a displacement of the offset plate (2) itself, for example when the offset plate (2) is formed by the surface of a cylinder. The cylinder, when it is rotated on its axis, then allows the offset plate (2) to move relative to the group (s) of heads. The offset plate is moved by moving means.
• the deposition of materials on some of the unit areas (9) is predefined according to the image to be printed.
• the preparation of the image to be printed, at one or more adapted devices (10), may thus require a programming, for example automated, of the projection of the material or materials in correlation with the movement of the group or groups heads of the deposition device (1) with respect to the offset plate (2) driven by the displacement means.
• the mesh carried by the offset plate (2) is made using materials allowing a confinement of material (s) deposited (s) in the surface of the unit areas and / or distribution (sufficiently) homogeneous on the surface of the unit areas, for example by virtue of metals with different lipophilic and hydrophilic properties such as aluminum or copper, or for example thanks to silicone.
• the offset plate (2) has a surface comprising a mesh of a plurality of hydrophilic and lipophilic unitary zones (9) capable of retain or fix a material, respectively, aqueous and fatty. Each of these areas is surrounded by an at least lipophobic peripheral area, to repel fats such as ink.
• a hydrophilic peripheral zone may also be suitable, such as glass or stainless steel for example, because it will be constantly wetted by the aqueous material (Le., The fountain solution) and will not be invaded by the fat.
• a hydrophobic and lipophobic peripheral zone (8) capable of repelling the fat and aqueous material, for example Teflon.
• the materials and / or the surface treatment of the materials within the mesh of the offset plate are adapted according to the type of material to be deposited, in particular its surface tension, so that the zones units confine the deposited material (either fountain solution or ink) and preferably that the peripheral areas are not invaded by the ink (fat in this case)
• the different unitary zones (9) for fixing the deposits of material (s) are arranged on the surface of the offset plate (2) so as to produce a mesh.
• This mesh positions the unitary zones (9) relative to one another so as to allow cutting which divides the entire surface of the offset plate (2) into a plurality of unitary zones (9) respectively selected by the means depositing (1) the material or materials.
• the unitary zones (9) are rectangular in shape, or even square, so that the mesh of the offset plate (2) realizes a grid.
• the different unit areas (9) have a hexagonal shape to allow an arrangement between them which is honeycomb.
• This second embodiment has the advantage of proposing unitary zones whose shape is close to a circle. This shape is thus better adapted to receive the deposit of a drop of material.
• the hexagonal shape of the different unitary zones (9) on the offset plate (2) makes it possible to reconcile an arrangement of these different zones between them to allow an optimal mesh of the entire surface of the offset plate (2) while being adapted to the roundness of the drops of material (s) which are likely to be deposited there.
• a peripheral zone (8) separating two consecutive unitary zones (9) has a width of between 5% and 50% of the width of a unitary zone (9).
• the peripheral zones (8) are arranged so that their width is on the one hand sufficiently wide to individualize each of the unitary zones and prevent a deposit of material (s) from moving from a unitary zone towards another, and on the other hand sufficiently restricted so that the repulsive effect of the peripheral zone on the material or materials deposited on a unit area has a sufficient repellent effect to prevent the spreading of the drop of material (s) out of the unit area on which it was deposited.
• the width of a unit area is of the order of at least 10 ⁇ at 50 ⁇ , preferably 20 ⁇ at 40 ⁇ , ideally 35 ⁇ .
• This particular width makes it possible to produce a unitary zone that is adapted to optimally receive the deposition of at least one drop of material (s).
• This width can also have a dimension of at least 5 ⁇ .
• the offset plate is set in motion by displacement means which sets the offset plate in motion. incremental between each deposition of material (s) deposited (s) by the nozzle or nozzles in the center of at least a unit area. Each increment depends on the shape of the unit area so that each unit area can face a nozzle projecting a fountain solution or a color material. Each increment may correspond to the size of at least one half-cell.
• each increment (il) corresponds to the size of a cell.
• each increment (i2) corresponds to the size of a half-cell.
• the offset plate is moved longitudinally by one increment ( ⁇ 2 ') the size of a cell so that each nozzle faces the center of a unitary surface.
• the group or groups of heads are moved longitudinally and parallel to the offset plate by one increment ( ⁇ 2 ') of the size of a cell so that each nozzle is in front of the center of a unitary surface.
• each group of heads has at least two nozzles separated by the size (i 2 ') of one cell, one of the nozzles projecting material at one increment and the other nozzle projecting material at the increment next.
• the device (0) for controlling the deposition of material (s) of the invention has the object of being integrated into a printing system which comprises in particular at least one material deposition device (3) and a pressure roller for transferring the image from the surface of the offset plate (2) to the surface of a substrate (4).
• the printing system may further comprise a drying device (5) for drying or polymerizing the material or materials deposited on the substrate (4) by the device according to the invention.
• the drying device (5) may be, for example, a heat source or any other drying means placed after the device according to the invention.
• the drying device (5) may, for example and without limitation, be a heat source, a system of polymerization by ultraviolet, infrared, electron beams, or any other source of polymerization.
• the advantage of drying by polymerization is that a dry matter is obtained without spending a lot of energy.
• the film of polymerizing material, after polymerization is very resistant to abrasion, aging, light, moisture ...
• a backpressure cylinder (3) is placed under the device according to the invention, the substrate (4) passing between the device according to the invention and the counterpressure cylinder (3).
• This counter-pressure cylinder (3) acts as support for the substrate (4) at the time of transfer of the material deposit (s).
• the system may also include a blanket disposed between the offset plate (2a, 2b, 2c) and the substrate (4).
• the substrate (4) can thus pass between the blanket and the counterpressure cylinder or cylinders (3a, 3b, 3c).
• the blanket makes it possible to receive the one or more colored materials and / or the fountain solution and to transfer the colored material (s) and / or the fountain solution received on the substrate (4).
• the method of implementing the device of the invention comprises in particular:
• the controlled deposition of material (s) of the offset plate (2) may consist of a step of controlled deposition of material (s) on unit areas of a fountain solution and a single color before the transfer step ink to the substrate (4) or deposition of material (s) on successive unit areas of a fountain solution and several different colors. It should be remembered that the deposition step of material (s) can be operated through one or more deposition nozzles as explained above.
• the fountain solution is sprayed by the nozzles into specific unit areas.
• the hydrophilic properties of the unit areas and the hydrophobic properties of the peripheral zones maintain each deposition of fountain solution in the unit area in which it was deposited.
• the fountain solution is projected into the determined unit areas where the deposition of color materials following the deposition of the fountain solution is not desired.
• the color materials may be, for example, greasy inks.
• the lipophilic properties of the unit areas and the lipophobic properties of the peripheral zones maintain each deposit of color materials in the unit area in which it was deposited.
• the colored materials do not penetrate into the unit areas where a fountain solution has been deposited.
• the method comprises several cycles. Each cycle comprises a step of controlled deposition of a fountain solution material by the one or more nozzles projecting a fountain solution material.
• the controlled deposition step of a fountain solution material may be followed by a step of controlled deposition of a material of fundamental color, for example a cyan ink, by the nozzle projecting a material of a fundamental color.
• the step of controlled deposition of a material of a fundamental color may be followed by a step of transferring the fountain material (s) and a fundamental color to a substrate (4).
• the transfer stage can be followed by a cleaning step of the offset plate (2) by the cleaning means (6).
• each cycle comprises a controlled deposition step of a fundamental color but it can be envisaged the controlled deposition of other colors that are not necessarily fundamental colors.
• the offset plate covers the same area of the substrate (4).
• the step of controlled deposition of material (s) comprises a step of controlled deposition of a fountain solution material by the one or more nozzles projecting a material of fountain solution.
• the controlled deposition step of a fountain solution material may be followed by a step of controlled deposition of material of each fundamental color by the nozzles projecting a material of fundamental color.
• the fundamental color materials are, for example, several inks of different colors, for example, fundamental colors such as cyan, yellow and magenta. The combination of these fundamental colors makes it possible to obtain a color determined by the quantity of each fundamental color.
• at least one nozzle (100) of each color projects a quantity of ink in the same unit area to obtain the desired color desired.
• the inks of each color projected in this unit area are then mixed during the path between the last ink projection and the transfer to the substrate (4).
• the method of the invention may also comprise:
• a step of preparing the image to be printed comprising at least one determination and programming of the part or parts the surface of the offset plate (2) intended to receive the material or materials,
• Each nozzle (100) is individually controlled by a computer system and a digital file.
• the digital file thus determines the cells (9a) on which the fountain solution (s) and the cells (9b) on which the colored material (s) must be deposited so that all the projections produce an image and / or a text on the surface of the offset plate (2) corresponding to the image and / or the text of the digital file for the colored material heads and the negative of the image for the fountain solution heads.
• the method comprises a step of drying or polymerization of the material or materials reported on the substrate (4) by the drying device (5) of the material or materials reported on the substrate (4).

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• 2012
  • 2012-05-07 FR FR1254183A patent/FR2990153B1/fr active Active
• 2013
  • 2013-05-07 US US14/398,812 patent/US9296202B2/en active Active
  • 2013-05-07 WO PCT/EP2013/059541 patent/WO2013167627A1/fr active Application Filing
  • 2013-05-07 JP JP2015510804A patent/JP6250641B2/ja active Active
  • 2013-05-07 EP EP13726440.4A patent/EP2847002B1/de active Active
• 2014
  • 2014-10-22 IL IL235280A patent/IL235280A0/en active IP Right Grant

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