JP2007125730A - Gravure platemaking roll and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new gravure platemaking roll, which is equipped with a surface reinforced covering layer, which has neither toxicity nor fear of outbreaking of environmental pollution at all, and is excellent in plate wear resistance, and its manufacturing method. <P>SOLUTION: This gravure platemaking roll comprises a metal hollow roll, a copper-plated layer, which is formed on the surface of the hollow roll and has a large number of gravure cells on its surface, and a polycarbonate coat to cover the surface of the copper-plated layer, wherein the thickness of the copper-plated layer is set to be 50-200 μm, the depth of the gravure cells is set to be 5-150μm and the preferable thickness of the polycarbonate coat is set to be 0.1-5 μm, preferably 0.1-3 μm and more preferably 0.1-1 μm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a gravure printing roll and a method for producing the same that can be provided with a surface-strengthening coating layer having sufficient strength without using chrome plating, and in particular, a polycarbonate coating as a surface-strengthening coating layer replacing a chromium layer. The present invention relates to a gravure plate making roll provided with a layer and a method for producing the same.

  In gravure printing, for a gravure printing roll (gravure cylinder), a micro concave portion (gravure cell) corresponding to the plate making information is formed to produce a plate surface, and the gravure cell is filled with ink and transferred to a printing material. is there. In a general gravure plate making roll, a copper plating layer (plate material) for forming a plate surface is provided on the surface of a metal hollow roll such as aluminum or iron, and a large number of minute plating is performed on the copper plating layer according to plate making information by etching. A concave portion (gravure cell) is formed, and then a hard chromium layer is formed by chromium plating for increasing the printing durability of the gravure plate making roll to form a surface-enhanced coating layer, and the plate making (plate surface production) is completed. However, because highly toxic hexavalent chromium is used in the chrome plating process, there is an extra cost to maintain work safety, and there are also problems of pollution, and the surface-enhanced coating layer replaces the chrome layer. The current situation is that the appearance of

  Polycarbonate, on the other hand,

It is a polymer compound of the type. General polycarbonate is a polycarbonate of bisphenol A represented by the following formula (1), and is a transparent flame-retardant thermoplastic. It has excellent heat resistance and aging resistance, is extremely strong and can withstand impact, and is widely used as an alternative to metal.

  This polycarbonate has properties that go between polyamide, polyethylene terephthalate, polybutylene terephthalate, and fluoroplastic, so molded products (household products, building materials, automotive parts, tools, machine parts, electrical appliances, electrical insulation materials) ), Optical discs, laminates, coatings, films, sheet products, and the like. However, in the manufacture of gravure platemaking rolls (gravure cylinders), a technique for forming a polycarbonate coating on a copper plating layer and using it as a surface reinforcing coating layer instead of a chromium layer has not yet been developed.

  In view of the above-mentioned problems of the prior art, the present inventor has conducted earnest research on a surface-enhanced coating layer that replaces the chromium layer, and has a strength comparable to that of the chromium layer by forming a polycarbonate coating and is not toxic. The present inventors have found that a surface-enhanced coating layer can be obtained without any concern about the occurrence of pollution.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a novel gravure plate making roll having a surface-enhanced coating layer that is non-toxic and has no fear of occurrence of pollution, and excellent in printing durability, and a method for producing the same.

  In order to solve the above-mentioned problems, a gravure printing roll of the present invention comprises a metal hollow roll, a copper plating layer provided on the surface of the hollow roll and having a number of gravure cells formed on the surface, and the copper plating layer It is characterized by comprising a polycarbonate film covering the surface.

  In the gravure printing roll of the present invention, the copper plating layer has a thickness of 50 to 200 μm, the gravure cell has a depth of 5 to 150 μm, and the silicon dioxide coating has a thickness of 0.1 to 5 μm, preferably 0.8. It is preferable that it is 1-3 micrometers, More preferably, it is 0.1-1 micrometer.

  The method for producing a gravure printing roll according to the present invention comprises a step of preparing a metal hollow roll, a copper plating step of forming a copper plating layer on the surface of the metal hollow roll, and a number of gravure on the surface of the copper plating layer. It comprises a gravure cell forming step for forming a cell and a polycarbonate coating forming step for forming a polycarbonate coating on the surface of the copper plating layer on which the gravure cell is formed.

  In the method for producing a gravure printing roll of the present invention, the copper plating layer has a thickness of 50 to 200 μm, the gravure cell has a depth of 5 to 150 μm, and the silicon dioxide coating has a thickness of 0.1 to 5 μm, preferably 0. It is suitable that the thickness is 0.1 to 3 μm, more preferably 0.1 to 1 μm.

  The polycarbonate coating is preferably formed by applying a polycarbonate solution dissolved in an organic solvent to the surface of the copper plating layer by a spray coating method, an inkjet method, a dipping method, or a fountain method.

  Examples of organic solvents for dissolving polycarbonate include trichloroethane, toluene, benzene, xylene, acetone, methyl ethyl ketone (MEK), ethyl acetate, methyl ethyl ether, methylene chloride, ethylene chloride, carbon disulfide, tetrahydrofuran, carbon tetrachloride, and N-methyl. -2-Pyrrolidone (NMP) and the like can be mentioned.

  The gravure cell may be formed by an etching method or an electronic engraving method, but an etching method is preferable. Here, the etching method is a method in which a gravure cell is formed by applying a photosensitive solution to the plate cylinder surface of a gravure cylinder and baking it directly, and then etching. The electronic engraving method is a method of engraving a gravure cell on a copper surface of a gravure cylinder by mechanically operating a diamond engraving needle by a digital signal.

  According to the present invention, the use of the polycarbonate coating as the surface-enhanced coating layer eliminates the need for chromium plating, thereby eliminating the use of highly toxic hexavalent chromium and extra work safety. The polycarbonate film has a great effect that it has a strength comparable to that of the chromium layer and excellent printing durability.

  Embodiments of the present invention will be described below, but these embodiments are exemplarily shown, and it goes without saying that various modifications can be made without departing from the technical idea of the present invention.

  FIG. 1 is an explanatory view schematically showing a production process of a gravure plate making roll according to the present invention, where (a) is an overall sectional view of a hollow roll, and (b) shows a state in which a copper plating layer is formed on the surface of the hollow roll. Partial enlarged sectional view, (c) is a partially enlarged sectional view showing a state where a gravure cell is formed on a copper plating layer of a hollow roll, and (d) is a portion showing a state where a polycarbonate film is formed on the surface of the copper plating layer of the hollow roll. It is an expanded sectional view. FIG. 2 is a flowchart showing a method for producing a gravure plate-making roll of the present invention.

  The method of the present invention will be described with reference to FIGS. In FIG. 1A, reference numeral 10 denotes a plate base material, and a metal hollow roll made of aluminum, iron or the like is used (step 100 in FIG. 2). A copper plating layer 12 is formed on the surface of the hollow roll 10 by a copper plating process (step 102 in FIG. 2).

  A large number of minute recesses (gravure cells) 14 are formed on the surface of the copper plating layer 12 (step 104 in FIG. 2). As a method for forming the gravure cell 14, an etching method (a photosensitive liquid is applied to the plate cylinder surface and directly baked and then etched to form the gravure cell 14) or an electronic engraving method (a diamond engraving needle is machined by a digital signal) A known method such as engraving the gravure cell 14 on the copper surface can be used, but an etching method is preferred.

  Next, a polycarbonate film 16 is formed on the surface of the copper plating layer 12 (including the gravure cell 14) on which the gravure cell 14 is formed (step 106 in FIG. 2). As a method for forming the polycarbonate film 16, a polycarbonate solution dissolved in an organic solvent may be applied by a spray coating method, an inkjet method, a dipping method, or a fountain method.

  Examples of organic solvents for dissolving polycarbonate include trichloroethane, toluene, benzene, xylene, acetone, methyl ethyl ketone (MEK), ethyl acetate, methyl ethyl ether, methylene chloride, ethylene chloride, carbon disulfide, tetrahydrofuran, carbon tetrachloride, and N-methyl. -2-Pyrrolidone (NMP) or the like can be used.

  By causing the above-described polycarbonate coating 16 to act as a surface-enhanced coating layer, it is possible to obtain a gravure printing roll 10a that is not toxic and that there is no concern about the occurrence of pollution and that has excellent printing durability.

  The copper plating layer has a thickness of 50 to 200 μm, the gravure cell has a depth of 5 to 150 μm, and the silicon dioxide coating has a thickness of 0.1 to 5 μm, preferably 0.1 to 3 μm, more preferably 0.1. It is preferable that it is ˜1 μm.

  The present invention will be described more specifically with reference to the following examples. However, it is needless to say that these examples are shown by way of illustration and should not be construed in a limited manner.

Example 1
Using a boomerang line (a gravure printing roll manufacturing apparatus manufactured by Sink Laboratories, Inc.), formation of the silver plating layer and etching treatment described below were performed. First, a gravure cylinder (aluminum hollow roll) having a circumference of 600 mm and a surface length of 1100 mm is mounted on the plating tank, the anode chamber is brought close to the hollow roll up to 20 mm by an automatic slide device by a computer system, the plating solution is overflowed, and the hollow roll Was completely immersed to form a copper plating layer having a thickness of 18 A / dm ² at 6.0 V and a thickness of 80 μm. The plating time was 20 minutes, and the surface of the plating was free of spots and pits, and a uniform copper plating layer was obtained. The surface of the copper plating layer was polished for 12 minutes using a 4H polishing machine (Sink Laboratory polishing machine) to make the surface of the copper plating layer a uniform polishing surface.

A photosensitive film (thermal resist: TSER-2104E4) was applied to the copper plating layer formed above (fonte coater) and dried. The film thickness of the obtained photosensitive film was 4 μm as measured by a film thickness meter (F20 manufactured by FILLMETRICS, sold by Matsushita Techno Trading). The image was then developed with laser exposure. It said laser exposure was carried out a predetermined pattern exposed in the exposure condition 5 min / m ^2/10 W using a Laser Stream FX. The development was performed at 24 ° C. for 60 seconds at a developer dilution ratio (stock solution 1: water 7) using a TLD developer (Sink Laboratory Co., Ltd. developer) to form a predetermined pattern. This pattern was dried (burned) to form a resist image.

  Further, cylinder printing was performed to engrave an image composed of gravure cells, and then the resist image was removed to form a printing plate. At this time, a cylinder was manufactured with a gravure cell depth of 12 μm. The etching was performed by a spray method under the conditions of a copper concentration of 60 g / L, a hydrochloric acid concentration of 35 g / L, a temperature of 37 ° C., and a time of 70 seconds.

  The hexavalent chromium alternative film formation according to the present invention was performed as follows. A solution of polycarbonate (product name: Caliber, manufactured by Sumitomo Dow Co., Ltd.) dissolved in methyl ethyl ketone (MEK) was inkjet-applied to the cylinder on which the printing plate was formed. The coating film thickness uniformly applied to the cylinder was 0.8 μm. The cylinder coated with this polycarbonate solution was left at room temperature. In this way, a gravure printing roll (gravure cylinder) was completed. The measured Vickers hardness of the cylinder surface was 2500.

  Subsequently, cyan ink Zahn cup viscosity 18 seconds (water-based ink Super Lampy Pure Indigo 800PR-5 manufactured by Sakata Inks Co., Ltd.) was applied to the obtained gravure cylinder as a printing ink, and OPP (Oriented Polypropylene Film: biaxially stretched polypropylene film). A printing test (printing speed: 120 m / min) was performed. The obtained printed matter had no plate fog and could be printed up to a length of 50,000 m. The accuracy of the pattern did not change. Also, there was no problem with the adhesion of the polycarbonate film to the etched copper plating cylinder. Since the gradation from the highlight portion to the shadow portion of the gravure cylinder of the present invention was not different from that of the chrome-plated gravure cylinder produced according to a conventional method, it is determined that there is no problem in ink transferability. As a result, it was confirmed that the polycarbonate film had a performance comparable to that of the conventional chromium layer and could be sufficiently used as a substitute for the chromium layer.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the manufacturing process of the gravure plate-making roll of this invention typically, (a) is whole sectional drawing of a hollow roll, (b) is the partial expanded section which shows the state which formed the copper plating layer on the surface of the hollow roll (C) is a partially enlarged sectional view showing a state in which a gravure cell is formed on a copper plating layer of a hollow roll, (d) is a partially enlarged sectional view showing a state in which a polycarbonate film is formed on the surface of the copper plating layer of the hollow roll. It is. It is a flowchart which shows the manufacturing method of the gravure printing roll of this invention.

Explanation of symbols

10: Plate base material (hollow roll), 10a: Gravure plate roll, 12: Copper plating layer, 14: Gravure cell, 16: Polycarbonate coating.

Claims (6)

  A gravure comprising a metal hollow roll, a copper plating layer provided on the surface of the hollow roll and having a number of gravure cells formed on the surface, and a polycarbonate film covering the surface of the copper plating layer Plate making roll.   2. The gravure printing roll according to claim 1, wherein the copper plating layer has a thickness of 50 to 200 [mu] m, the gravure cell has a depth of 5 to 150 [mu] m, and the polycarbonate coating has a thickness of 0.1 to 5 [mu] m. .   A step of preparing a metal hollow roll, a copper plating step of forming a copper plating layer on the surface of the metal hollow roll, a gravure cell forming step of forming a number of gravure cells on the surface of the copper plating layer, A method for producing a gravure printing roll, comprising a polycarbonate film forming step of forming a polycarbonate film on a surface of a copper plating layer on which a gravure cell is formed.   4. The gravure printing roll according to claim 3, wherein the copper plating layer has a thickness of 50 to 200 μm, the gravure cell has a depth of 5 to 150 μm, and the polycarbonate coating has a thickness of 0.1 to 5 μm. Production method.   5. The polycarbonate film is formed by applying a polycarbonate solution dissolved in an organic solvent to the surface of the copper plating layer by a spray coating method, an inkjet method, a dipping method, or a fountain method. The manufacturing method of the gravure plate-making roll of description.   The method for producing a gravure printing roll according to any one of claims 3 to 5, wherein the gravure cell is formed by an etching method or an electronic engraving method.

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