JP2006088526A - Screen printing platemaking equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide platemaking equipment of a screen printing plate which has an intercepting member patterned with high clearness and so provided firmly as not to slip off and can form a printed image of high resolution. <P>SOLUTION: This platemaking equipment of the screen printing plate has, in the constitution, at least an ink permeating member, a liquid ink-intercepting material which is cured by ultraviolet light, a discharge means which comprises one or a plurality of nozzles giving the liquid ink-intercepting material to the ink permeating member to form a pattern of this material on the ink permeating member, a curing means which cures the liquid ink-intercepting material by exposing the pattern or the ink permeating member including the pattern to the ultraviolet light immediately after the pattern is formed on the ink permeating member out of the liquid ink-intercepting material, and a moving means which moves relatively the ink permeating member, the discharge means and the curing means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a screen printing plate making apparatus for making a screen printing plate by depositing an ink blocking material on the surface of a mesh screen according to a desired image pattern.

  In screen printing, a screen printing plate is set on a screen printing machine, printing ink (hereinafter simply referred to as “ink”) is placed, and printing is performed on a printing material such as paper or cloth using a squeegee. There are mainly two printing methods, squeegee printing and press printing. Squeegee printing is an elastic rubber spatula called a squeegee, and the tip of the squeegee is slid while applying pressure while maintaining a certain angle on the plate, and the ink on the plate is pushed out to the printing medium. In press printing, ink is placed on a printing plate, a uniform force is applied from above the plate through a flat plate or the like, and the ink on the plate is pushed out onto a substrate. The ink passes through the transmission part (mesh part) of the screen, and an image is printed on the substrate. Widely used as a technology that allows printing on materials and shapes that are difficult to print with other printing technologies, such as printing on cloth, plastic, printed boards, glass, porcelain, metal plates, printing on cubes or curved surfaces, etc. .

  Conventionally, as a plate making method of a screen printing plate (screen printing plate), a direct plate making method, an indirect plate making method, and a direct indirect plate making method are known.

  In the direct plate-making method, a photosensitive resin emulsion is applied to a mesh screen stretched on a mold and dried, and then a positive film with a pattern formed on a transparent sheet is brought into close contact with it, and developed by irradiation with light. To make a screen printing plate. However, this method requires advanced technology to uniformly coat the photosensitive resin emulsion, requires advanced skills such as working in a dark room, many man-hours and equipment, and is also mixed with dust and irregular reflection of the mesh. There is a problem with pattern edge rounding caused by

  In the indirect plate making method, a film-like support is separately prepared by previously performing exposure, development, etc. to form a pattern. Next, the film-like support is superposed on the mesh-like screen so that the pattern contacts, and only the film-like support is removed and the pattern is transferred to the mesh-like screen.

  In this method, since a film-like support coated with an emulsion is separately prepared and previously formed with a pattern, a technique for coating a photosensitive resin emulsion like the direct plate making method is particularly required. In addition, the mesh has no irregular reflection and a resolution close to that of a positive film can be obtained, but there is a problem that the adhesion strength between the pattern and the mesh screen is low and sufficient durability cannot be maintained. Therefore, it is disadvantageous for mass printing and it is difficult to maintain the quality of the printed image constant.

  The direct and indirect plate making method is a method devised to achieve both the simplicity of the indirect plate making method and the advantages such as the strength of the direct plate making method. That is, after a screen printing direct method film coated with a photosensitive resin layer on one side is adhered to a mesh screen stretched on a mold, water or a photosensitive resin liquid is applied from the non-adhesive side of the mesh screen. The photosensitive resin layer is easily bonded to the mesh screen by supplying, applying, and drying. Thereafter, a positive printing film is used for exposure and development to produce a screen printing plate.

  In this method, since the photosensitive resin layer is adhered with water or a photosensitive resin solution, the adhesive strength is stronger than the indirect plate making method, and the emulsion is protected with a film until just before exposure, so it has a certain durability. Not easily affected by dust and dirt.

  In the direct and indirect plate making method, some of the conventional problems are solved, but a screen printing film coated with a positive film or a photosensitive resin layer is indispensable, and this causes an increase in printing cost when printing a small amount. Furthermore, since exposure / development steps are necessary, problems remain in terms of simplification of the steps and cost reduction.

  For such problems, a hot-melt ink in a molten state, a hot-melt ink added with a photo-curable material or a photo-curable material, directly or A method has been proposed in which a screen printing plate is prepared by shielding ink at a portion where hot-melt ink or the like is solidified by transfer and solidified (for example, see Patent Document 1).

According to this method, a hot-melt ink or a photo-curing material, which is an ink blocking material that shields ink in a region where the ink is to be shielded, of a mesh-like screen (紗) that is a transparent member that transmits ink is selectively used. Since the image is formed directly using ink-jet technology, it is not necessary to carry out development, washing, and other steps for fixing to the mesh screen and ink. And can be manufactured at a low cost. In addition, it is a technology that is safe and environmentally friendly, with no chemical reaction or the like, and no selective waste due to selective shielding.
JP 2004-98607 A

  However, when reproducing continuous tone using a screen printing plate, it is generally necessary to have a high-definition shielding portion that blocks ink permeation as well as printing durability. Conventional screen printing plate making apparatuses using ink jet technology using hot melt ink have insufficient printing durability, and screen printing plate making apparatuses using ink curing technology using photocurable materials require time from pattern formation to light curing. In the meantime, there is a problem that the photocurable material spreads by permeation and the resolution is lowered.

  That is, as described above, the conventional screen printing plate making apparatus has a serious defect that a high-resolution screen printing plate cannot be obtained.

  The present invention has been made in view of the above, and an object of the present invention is to solve various problems in the production of a screen printing plate by the conventional ink jet technique and achieve the following object.

  That is, the present invention has an object to provide a plate making apparatus for a screen printing plate that is firmly provided so that a highly sharply patterned blocking member does not fall off and can form a high-resolution printed image. Provided a screen printing plate making apparatus capable of forming a strong blocking member (pattern image) having no sharp edges of the pattern due to the irregular reflection of light, sharp edges and no dropout, and capable of forming a high-resolution print image The purpose is to do.

  A further object of the present invention is to provide a printed matter by a screen printing plate that can be produced easily and at low cost with a small number of steps.

  In order to solve such problems, the screen printing plate making apparatus according to the present invention provides an ink transmitting member that transmits ink, a liquid ink blocking material that is cured by ultraviolet light, and a liquid ink blocking material to the ink transmitting member. Discharge means comprising one or a plurality of nozzles for forming a pattern with a liquid ink blocking material on the ink transmitting member, and ink containing the pattern or pattern immediately after the pattern is formed with the liquid ink blocking material on the ink transmitting member At least a curing unit that irradiates the transmitting member with ultraviolet light to cure the liquid ink blocking material and a moving unit that relatively moves the ink transmitting member, the discharge unit, and the curing unit are provided.

  According to this, immediately after the liquid ink blocking material adheres to and penetrates the ink blocking member, curing starts and the liquid ink blocking material can be prevented from penetrating and spreading along the gap of the ink transmitting member. High-resolution patterns can be formed.

  Further, in the screen printing plate making apparatus, as shown in claim 2, the contact angle of the liquid ink blocking material with respect to the ink transmitting member is 90 ° to 30 °. According to this, the liquid ink blocking material easily penetrates into the gap between the ink permeable members by capillary action, and the ink permeable member can be completely shielded.

  In the screen printing plate making apparatus, as shown in claim 3, the discharge means and the hardening means are provided close together and integrally. According to this, it is possible to irradiate the ink transmissive member with ultraviolet light with a simple configuration immediately after forming the pattern on the ink permeable member with the liquid ink blocking material.

  According to the present invention, it is possible to form a high-resolution printed image by firmly providing a highly sharply patterned blocking member so as not to drop off.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a screen printing plate (ink transmitting member or mesh screen) used in the present invention. In FIG. 1, 1 is a mesh-like part, 2 is a support base material. When a screen printing plate is transported in a screen printing plate making apparatus, a sufficient strength cannot be ensured only with the mesh-shaped portion 1, so a support base material 2 is provided around the mesh-shaped portion 1 to reinforce and maintain the shape. It has been. The mesh portion 1 is not particularly limited as long as it has a structure capable of passing printing ink, and can be appropriately selected from known materials.

  FIG. 2 shows an enlarged view of the mesh portion 1. The mesh portion 1 has a gap 4 such as a mesh shape or a mesh shape with the ink blocking portion 3, and the gap 4 may have any shape. Further, the material of the mesh portion 1 is not particularly limited, and can be appropriately selected from materials generally used for screen printing, such as nylon, silk, polyester, polyarylate, polyamide, and stainless steel. The mesh size of the mesh-like portion 1 is preferably 80 to 500 / inch, more preferably 300 to 500 / inch.

  Next, the liquid ink blocking material used in the present invention will be described in detail. The liquid ink blocking material used in the present invention is composed of an ultraviolet curable resin. The ultraviolet curable resin is generally called a UV resin and is cured by photopolymerization with ultraviolet light. The ultraviolet curable resin is composed of a photopolymerizable resin, a photopolymerization initiator, a colorant, an auxiliary agent, and the like. Photopolymerizable resins are classified into high viscosity oligomers and low viscosity oligomers or monomers called reactive diluents. In order to adjust the viscosity of the liquid ink blocking material, an oligomer having a relatively high viscosity and a reactive diluent composed of monomers having a high boiling point and polyester acrylates having a low viscosity are mixed. Commonly used oligomers include polyester acrylate, epoxy acrylate, and urethane acrylate. The photopolymerization initiator generates radicals by ultraviolet energy, which reacts with a reactive group of a monomer or oligomer to initiate polymerization. Further, a pigment may be added as a colorant to facilitate plate inspection after plate making. The pigment has a great influence on the curability of the ultraviolet curable resin because the ultraviolet absorption property changes depending on the hue. Therefore, it is necessary to select a pigment that has good visibility and does not lower the curability as much as possible. Depending on the pigment, the storage stability of the UV curable resin may be hindered and gelation may occur, so care should be taken and other monomer resistance should be taken into consideration.

  As for auxiliary agents, UV curable resins generate radicals under the influence of heat or the like even when UV rays are not present, and may cause a gelation phenomenon called dark reaction. A polymerization inhibitor is used to prevent dark reactions. Added. Other antifoaming agents are also added.

  Furthermore, a necessary amount of a surfactant is added to adjust the contact angle of the liquid ink permeable member used in the present invention with respect to the mesh portion 1 to 90 ° or less and 30 ° or more. By adding a surfactant, it is possible to adjust the contact angle of the liquid ink blocking material (ultraviolet curable resin) to the mesh portion 1 to be 90 ° to 30 °.

  FIG. 3 shows a state in which the liquid ink blocking material 5 set so that the contact angle with respect to the surface of the mesh-like portion 1 is 90 ° to 30 ° is discharged as a droplet onto the mesh-like portion 1. When the droplet of the liquid ink blocking material 5 touches the surface of the ink blocking portion 3 of the mesh-shaped portion 1, the contact angle is 90 degrees or less, so that the wettability is good and the gap 4 is absorbed rapidly by the capillary phenomenon. The gap 4 is filled easily. However, if the contact angle becomes too small (30 ° or less), the wetness of the liquid ink blocking material with respect to the ink blocking portion 3 of the mesh-shaped portion 1 is too high and spreads rapidly on the surface of the ink blocking portion 3, causing bleeding. It becomes.

  On the other hand, FIG. 4 shows a state in which the liquid ink blocking material 5 in which the contact angle of the mesh-shaped portion 1 with respect to the surface of the ink blocking portion 3 is set to 90 ° or more is discharged as a droplet onto the mesh-shaped portion 1. When the droplet of the liquid ink blocking material 5 touches the surface of the mesh portion 1, the contact angle is 90 degrees or more, so the wettability is poor, and it adheres to the surface of the mesh portion 1 in a spherical shape. I can't get in enough. The liquid ink blocking material cured in such a state has a weak adhesive force with respect to the mesh portion 1 and cannot secure printing durability during printing.

  Therefore, the contact angle of the liquid ink blocking material 5 with respect to the mesh portion 1 is preferably set to 90 ° to 30 °.

  Further, the liquid ink blocking material 5 used in the present invention needs to be finished to a liquid having a relatively low viscosity in order to be discharged by an ink jet recording head. In order to discharge from the ink jet recording head as a stable droplet without generating satellite or the like, the viscosity of the liquid ink blocking material 5 needs to be 30 cps or less, preferably 20 to 8 cps. However, in the case of using the ink blocking material 5 and the member through which the ink blocking material 5 passes, the heating means of the recording head, or the case of using the recording head having a larger discharge force, the viscosity exceeds this range and takes a large value. It is possible.

  The remaining liquid ink blocking material 5 that fills the plurality of pores has a high viscosity (optimally 8 to 20 cps), so that the liquid ink blocking material 5 spreads slightly around and rises. Therefore, the liquid ink blocking material 5 does not spread more than necessary, and a high-resolution image close to the diameter of the droplet can be formed. In this case, the amount of liquid droplets to be ejected differs depending on the resolution, and when forming an image with small dots (that is, high resolution), the amount of liquid droplets is also small. For example, when an image is formed with a mesh portion 1 of about 500 lines / inch, it is desirable that the liquid ink blocking material 5 has a droplet amount of about 80 pl (picoritter). In other words, in the case of a mesh-like part 1 of about 500 lines / inch, the gap 4 is about 25 μm, while the droplet of the liquid ink blocking material 5 has a diameter of about 46 μm in the case of 80 pl. And can draw high-resolution patterns.

  However, when a low resolution is sufficient, an image is formed with large dots (low resolution), and the droplets are also large, so that the mesh-shaped portion 1 having a coarse size is used.

  FIG. 5 shows a schematic configuration diagram of a screen printing plate making apparatus according to the present invention. The screen printing plate making apparatus includes a screen printing plate 6, a conveyance unit including a conveyance roller 8 that conveys the screen printing plate 6, a slider 9 that moves across the screen printing plate 6 that is moved by the conveyance unit, and a magnet. 10, a linear motor 12 including a linear guide 11, a scale 13 received even in the vicinity of the linear motor 12 to detect position information and movement information of the slider 9, and a scale 13 provided on the slider 9. A linear encoder 14 for detection, a recording head 15 provided with a plurality of nozzles provided on the slider 9 for discharging an ink blocking material, and an irradiation width wider than the nozzle arrangement width of the recording head 15 provided integrally with the recording head 15. It is composed of an ultraviolet lamp 16 for curing the liquid ink blocking material discharged to the holding screen printing plate 6. . A liquid ink blocking material is supplied to the recording head 15 through a pipe 17.

  In the screen printing plate making apparatus configured as described above, the screen printing plate 6 is inserted into the feed roller 7 with the drawing surface up as preparation for plate making. When the plate making is started, the feed roller 7 and the transport roller 8 are operated to feed the screen printing plate 6, and when the tip of the screen printing plate 6 passes through the feed roller 7 and reaches a predetermined position, the feed roller 7 and the transport roller. The transport unit consisting of 8 stops. Next, the linear motor 12 operates, and the slider 9 moves across the screen printing plate 6. When the linear encoder 14 provided on the slider 9 reads the scale 12 and detects that the slider 9 has reached a predetermined position on the screen printing plate 6, the recording head 15 provided on the slider 9 rasterizes the pages for printing. In response to the drawing signal, the discharge of the liquid ink blocking material is started, and the liquid ink blocking material is attached to the image line portion to which the printing oil-based ink is applied in the printing process. Immediately after that, the liquid ink blocking material adhered to the screen printing plate 6 is irradiated with ultraviolet light from an ultraviolet lamp 16 mounted on the slider 9 integrally with the recording head 15 and cured by photopolymerization. In this way, the linear encoder 14 reads the scale 13 as the slider 9 of the linear motor 12 moves, and the recording head 15 moves from one end to the other end of the screen printing plate 6 according to the read position information. The blocking material is sequentially deposited and simultaneously cured by the ultraviolet lamp 16. Thus, a cured liquid ink blocking material image is formed in accordance with the information specified at the precise position. When the slider 9 moves to the other end of the screen printing plate 6 and adheres and cures the liquid ink blocking material to a predetermined position, the linear motor 12 reverses and the slider 9 returns to the original position along the linear guide 11. Return. During the operation of returning the slider 9 to the original position, the recording head 15 does not discharge the liquid ink blocking material, and only the transport unit operates, and a new portion of the screen printing plate 6 is recorded by the feed roller 7 and the transport roller 8. When set under the head 15, the transport unit composed of the feed roller 7 and the transport roller 8 stops again. Then, the recording head 15 provided on the slider 9 again moves from one end to the other end of the screen printing plate 6 along the linear guide 11 of the linear motor 12 so that the ink blocking material adheres and is cured by the ultraviolet lamp 16 as before. Is done. In this manner, the liquid ink blocking material is repeatedly attached and cured by the recording head 15 and the ultraviolet lamp 16 mounted on the slider 9 while intermittently feeding the screen printing plate 6 by the transport unit.

  When such a series of steps is completed, the production of the printing plate is completed, and the printing plate is set on a normal rotary press, and the necessary number of copies are printed.

  In the screen printing plate making apparatus shown in FIG. 5, the liquid ink blocking material is discharged by the recording head 15 only when the recording head 15 provided in the slider 9 moves in one direction, but ultraviolet lamps 16 are provided on both sides of the recording head 15. By providing it, it is possible to discharge and cure the liquid ink blocking material by the recording head 15 when the slider 9 reciprocates. Further, with this configuration, after the slider 9 moves from one end to the other end of the screen printing plate 6 and finishes the adhesion and curing of the liquid ink blocking material, recording is performed during the operation in which the slider 9 returns to the original position. If only the ultraviolet lamp 16 is irradiated without discharging the liquid ink blocking material by the head, the portion cured once by the ultraviolet lamp 16 is cured again, and the ultraviolet curable resin is cured more reliably. In addition, the light quantity of the ultraviolet lamp 16 can be reduced.

  As apparent from the above description, the present invention provides an ink permeable member that transmits ink, a liquid ink blocking material that is cured by ultraviolet light, and a liquid ink blocking material applied to the ink transmitting member. Discharge means comprising one or a plurality of nozzles for forming a pattern with a liquid ink blocking material and ultraviolet light on the ink transmitting member immediately after forming the pattern with the liquid ink blocking material on the ink transmitting member And at least a moving means for relatively moving the ink permeable member, the discharge means, and the curing means, and the ultraviolet lamp is disposed in close proximity to the recording head. In order to cure the liquid ink blocking material that has been adhered to the surface of the ink permeable member over time, Spread body shape ink blocking member is greatly reduced. As a result, the resolution is greatly improved.

  Also, by setting the contact angle of the liquid ink blocking material to 90 degrees or less with respect to the ink transmitting member, the wettability of the liquid ink blocking material to the ink transmitting member is improved, and the liquid ink blocking material is placed in the gap between the ink transmitting members. Since it penetrates and cures, strong adhesion is realized and printing durability at the time of printing can be secured.

  Furthermore, the screen printing plate manufacturing process can be configured simply with two steps of adhesion and curing of the liquid ink blocking material, which eliminates the need for the development process and the associated water washing process, making the apparatus very simple. Can be downsized.

  ADVANTAGE OF THE INVENTION According to this invention, the plate-making apparatus of the screen printing plate which can be firmly provided so that the highly sharply patterned shielding member may not drop off and can form a high-resolution print image can be provided.

The figure which shows schematic structure of the screen printing plate used for this invention The enlarged view of the mesh-shaped part of the screen printing plate by this invention The figure which shows the state by which the liquid ink blocking material by which the contact angle with respect to the surface of a mesh part was set to 90 degrees-30 degrees was discharged to the mesh part The figure which shows the state by which the liquid ink blocking material by which the contact angle with respect to the surface of a mesh part was set to 90 degrees or more was discharged to the mesh part Schematic configuration diagram of a screen printing plate making apparatus according to the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mesh-like part 2 Support base material 3 Ink block part 5 Liquid ink blocker

Claims (3)

  An ink permeable member that transmits ink, a liquid ink blocking material that is cured by ultraviolet light, and the liquid ink blocking material is applied to the ink transmitting member to form a pattern of the liquid ink blocking material on the ink transmitting member. Discharge means comprising one or a plurality of nozzles, and the liquid ink by irradiating the ink transmissive member including the pattern or pattern with ultraviolet light immediately after the ink permeable member is formed with the liquid ink blocking material. A screen printing plate making apparatus provided with at least a moving means for relatively moving a curing means for curing a blocking material, the ink transmitting member, the discharge means, and the curing means.   2. The screen printing plate making apparatus according to claim 1, wherein a contact angle of the liquid ink blocking material with respect to the ink transmitting member is 90 to 30 degrees.   The screen printing plate making apparatus according to claim 1, wherein the discharge unit and the curing unit are integrally provided close to each other.

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