JP2006243150A - Photosensitive resin printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin printing plate which is excellent in reproducibility of a fine independent point and of an image in plate-making and in printing. <P>SOLUTION: The photosensitive resin printing plate is obtained from a photosensitive resin laminated body at least having a substrate, a photosensitive resin layer, a protective layer, and a cover film, and is characterized by having 50-60° Shore D hardness of the photosensitive resin layer, and 30% or more impact resilience thereof. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photosensitive resin printing plate, and more particularly to a photosensitive resin printing plate excellent in fine independent points and image reproducibility during plate making and printing.

  In general, a photosensitive resin composition used for a relief plate for printing generally contains a soluble polymer, a photopolymerizable unsaturated group-containing monomer, and a photopolymerization initiator as essential components. Additives such as agents are blended.

  Conventionally, the photosensitive resin composition layer is irradiated with actinic rays through a negative film (or positive film) having a transparent image portion to cure the exposed portion of the photosensitive layer, and then the non-exposed portion of the photosensitive layer is appropriately formed. It is widely known to prepare a relief plate for printing by dissolving and removing with a solvent.

Recently, user demands for photosensitive resin compositions used for printing relief plates have progressed in the direction of reproducing fine patterns in a short exposure time, and the retention of the minimum independent point has changed from 200 μ to 100 μ. Yes. Further, the minimum highlight used for printing a photograph is required to be 1% of 200 lines, which is finer than 3% of 150 lines. However, as a conventional technique corresponding to these requirements, a photosensitive resin laminate (Patent Document 1) in which a photosensitive resin layer having a thickness of 200 μm or more is provided on a photosensitive resin layer that is 100 μm or more photocured on a support is disclosed. Examples include photosensitive resin laminates (Patent Document 2) in which a cushion layer of a soft resin is provided on a support to improve ink loading, but fine points are reproduced with a short exposure time in plate making, and at the time of printing In addition, it was not possible to obtain a photosensitive resin laminate capable of obtaining a sharp printed product with less weight.
JP 58-85435 A JP-A-54-85803

  An object of the present invention is to provide a photosensitive resin printing plate excellent in fine independence and image reproducibility during plate making and printing, and to solve the above problems. .

  As a result of diligent research, the present inventors finally completed the present invention in order to reproduce fine independent points and images with a short exposure time in plate making and to obtain a sharp printed material with less weight at the time of printing. It was. That is, the present invention is (1) a photosensitive resin printing plate obtained from a photosensitive resin laminate having at least a support, a photosensitive resin layer, a protective layer, and a cover film, and after exposure plate making, the photosensitive resin layer A photosensitive resin printing plate having a Shore D hardness of 50 ° to 60 ° and a rebound resilience of 30% or more. (2) The photosensitive resin printing plate according to (1), wherein at least one of the crosslinking agents contained in the photosensitive resin layer is glycerin dimethacrylate.

The printing plate of the present invention can provide a photosensitive resin laminate for a printing relief plate having excellent reproducibility of fine independent points during plate making and printing, and contributes greatly to the industry.

  In the present invention, it is preferable that the Shore D hardness of the photosensitive resin layer after exposure is 50 ° to 60 ° and the rebound resilience is 30% or more. If the Shore D hardness is less than 50 °, the relief layer is greatly deformed by the printing pressure and the halftone dots and fine lines become thick. On the other hand, if it exceeds 70 °, the ink on the solid part of the plate becomes poor and it becomes difficult to print cleanly. The rebound resilience of the photosensitive resin layer after exposure may be 30% or more, preferably 33% or more, and desirably 36% or more. If the impact resilience is less than 15%, the cushion effect is small, which is not preferable.

  Next, in the present invention, the thickness of the photosensitive resin layer is preferably 350 to 1500 μm, more preferably 550 to 1200 μm, and desirably 600 to 800 μm. If it exceeds 1500μ, it is not preferable because the reproducibility of the point at the time of plate making decreases, and if it is less than 350μ, the ink adheres to the adhesive layer on the support and stains (background stain) occur in the non-image area of the printed matter. Absent.

  The photosensitive resin layer used in the printing plate of the present invention contains a known polymer binder, a crosslinking agent (also referred to as an ethylenically unsaturated compound), and a photoinitiator composition. Furthermore, other additives such as plasticizers, thermal polymerization inhibitors, dyes, pigments, ultraviolet absorbers, fragrances or antioxidants may be included. The polymer binder used in the present invention is preferably a polymer binder that can be dissolved or dispersed in water or a mixture of water and alcohol. Specifically, polyether amide (for example, JP-A-55-79437) ), Polyether ester amide (for example, JP-A No. 58-113537), tertiary nitrogen-containing polyamide (for example, JP-A No. 50-76055), ammonium salt type tertiary nitrogen atom-containing polyamide (for example, JP-A No. Sho). 53-36555), an addition polymer of an amide compound having one or more amide bonds and an organic diisocyanate compound (for example, JP-A-58-140737), an addition weight of a diamine having no amide bond and an organic diisocyanate compound And the like (for example, Japanese Patent Laid-Open No. 4-97154). Amide and ammonium salt type tertiary nitrogen atom-containing polyamide are preferable.

  The crosslinking agent (ethylenically unsaturated compound) preferably used is a ring-opening addition reaction product of polyglycidyl ether of polyhydric alcohol with methacrylic acid and acrylic acid, and dipentaerythritol is used as the polyhydric alcohol. , Pentaerythritol, trimethylolpropane, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, ethylene oxide adducts of phthalic acid, diglycidyl ether acrylic acid adducts of bisphenol A and bisphenol F, and the like. In addition, two or more of these compounds can be used in combination. In the present invention, glycerin dimethacrylate is particularly preferable.

  Furthermore, examples of the photoinitiator composition used in the present invention include benzophenones, benzoins, acetophenones, benzyls, benzoin alkyl ethers, benzyl alkyl ketals, anthraquinones, thioxanthones, and the like. Specifically, benzophenone, chlorobenzophenone, benzoin, acetophenone, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, benzyl diethyl ketal, benzyl diisopropyl ketal, anthraquinone, 2-ethylanthraquinone , 2-methylanthraquinone, 2-allylanthraquinone, 2-chloroanthraquinone, thioxanthone, 2-chlorothioxanthone and the like.

  For the adhesive layer used in the present invention, a known adhesive can be used. Specific examples include polyester urethane adhesives and epoxy adhesives obtained by curing soluble polyester with polyvalent isocyanate. Among these, a polyester urethane adhesive is preferable because it is excellent in adhesion to a photosensitive resin, and an adhesive made of polyester and isocyanurate type polyisocyanate is more preferable among polyester urethane adhesives. Other minor components can be added to the adhesive layer composition. Examples of additives include plasticizers, dyes, ultraviolet absorbers, antihalation agents, surfactants, and photopolymerizable vinyl monomers.

  Examples of the support used in the present invention include a plastic film such as a polyester film, a metal plate such as iron, stainless steel, and aluminum, and a metal-deposited film.

  The photosensitive resin laminate (also referred to as a photosensitive resin printing original plate) used in the printing plate of the present invention has a desired thickness by, for example, any known method such as hot pressing, casting, melt extrusion, or solution casting. The sheet-form photosensitive resin printing original plate can be obtained.

  In the present invention, a protective layer (also referred to as a cover film) may be laminated on the photosensitive resin layer, and the protective layer has an adhesive property to a film-like plastic, for example, a polyester film having a thickness of 125 μm. A transparent polymer having a film thickness of 1 to 3 μm that can be dispersed or dissolved in a developer is used. Even if the surface adhesiveness of the photosensitive layer is strong by laminating the film having the thin coating on the photosensitive resin original plate so that the coating is in contact with the photosensitive layer, the plastic is used before the exposure operation. The film can be easily peeled from the photosensitive resin original plate.

  As a method of preparing a printing plate from the photosensitive resin laminate of the present invention, first, a negative film or a positive film having a transparent image portion is closely adhered on the photosensitive resin layer, and actinic rays are irradiated from above. When the exposure is performed, the exposed portion is cured and insolubilized. For the actinic ray, a light source such as a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a xenon lamp or a chemical lamp having a wavelength of about 300 to 400 nm is used.

  After the exposure, the non-exposed portion is dissolved and removed using an appropriate solvent, preferably water, particularly neutral water, so that the development is performed quickly in a short time, and a printing plate (relief plate) is obtained. As the developing method, it is preferable to use a spray developing device, a brush developing device, or the like.

Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” means “parts by weight”. In addition, after shape | molding to this invention laminated body (printing original plate) and photocuring, Shore D hardness, the solvent absorption weight increase rate with respect to normal hexane, exposure time, and image development time were measured with the following method. In addition, the sample for a measurement uses the photosensitive resin laminated body which provided the 3 mm photosensitive resin layer on the 250-micrometer polyester support body, and laminated | stacked the 125-micrometer polyester film on the photosensitive resin layer surface. Using a 25 W / m @ 2 chemical lamp from the surface, exposure was performed for 10 minutes from a distance of 5 cm from the surface of the photosensitive resin, and photocured. This sample was stored for 24 hours at 20 ° C. and a relative humidity of 65% to prepare a sample.
(1) Shore D hardness: Measured at 25 ° C. using a Shore durometer (Shore D type) manufactured by West German Zbic.
(2) Rebound resilience: A steel ball ball having a diameter of 10 mm (weight 4.16) was dropped from a height of 20 cm, and the bounce height (a) was read and displayed as (a / 20) × 100%. The measurement was performed under the conditions of 25 ° C. and 70% RH.

Reference example 1
2-methylpentamethylenediamine (MPDA) 2.0 parts, 1,4-bisaminopropylpiperazine (BAPP) 7.9 parts, polyethylene glycol hexamethylene diisocyanate reactant (HE-600) 45.2 parts and adipic acid 1 .7 parts were placed in 100 parts of methanol and a heated dissolution kettle with stirring, and after sufficient nitrogen substitution, the flask was sealed and gradually heated to 65.degree. After stirring for about 2 hours, 5.0 parts of N-ethyltoluenesulfonic acid amide, 0.03 part of 1,4-naphthoquinone and 0.1 part of hydroquinone monomethyl ether were added and dissolved by stirring for another 30 minutes. Thereafter, 2.5 parts of glycidyl methacrylate (GMA), 18 parts of water, 0.3 part of ammonium sulfite, 0.1 part of oxalic acid, 1.2 parts of adipic acid, 1.0 part of benzyldimethyl ketal as a photoinitiator, glycerin 24.8 parts of dimethacrylate (Kyoeisha Chemical Co., Ltd. crosslinker light ester G101P), and Kyoeisha Chemical Co., Ltd. crosslinker trimethylolpropane polyglycidyl ether- (meth) acrylic acid adduct CHA 8.3 parts were further added and added. The mixture was dissolved with stirring for a minute. Subsequently, the temperature was gradually raised to distill methanol and water, and the mixture was concentrated until the temperature in the kettle reached 110 ° C. At this stage, a fluid and viscous photosensitive resin composition 1 was obtained. The photosensitive resin composition 1 had a Shore D hardness of 57 ° and an impact resilience of 35% after ultraviolet exposure.

Reference example 2
2.4 parts of 2-methylpentamethylenediamine (MPDA), 7.2 parts of 1,4-bisaminopropylpiperazine (BAPP), 45.4 parts of polyethylene glycol hexamethylene diisocyanate reactant (HE-600) and adipic acid 1 .7 parts were placed in 100 parts of methanol and a heated dissolution kettle with stirring, and after sufficient nitrogen substitution, the flask was sealed and gradually heated to 65.degree. After stirring for about 2 hours, 5.0 parts of N-ethyltoluenesulfonic acid amide, 0.03 part of 1,4-naphthoquinone and 0.1 part of hydroquinone monomethyl ether were added and dissolved by stirring for another 30 minutes. Thereafter, 1.5 parts of glycidyl methacrylate (GMA) was added and further stirred and dissolved for 30 minutes. Thereafter, 18 parts of water, 0.3 part of ammonium sulfite, 0.1 part of oxalic acid, 1.0 part of adipic acid, 1.0 part of benzyldimethyl ketal as a photoinitiator, glycerin dimethacrylate (cross-linking agent manufactured by Kyoeisha Chemical Co., Ltd.) Light ester G101P) 24.8 parts, 13.7 parts of cross-linking agent epoxy ester 40EA manufactured by Kyoeisha Chemical Co., Ltd. was further added and dissolved with stirring for 30 minutes. Next, the temperature was gradually raised to distill methanol and water, and the mixture was concentrated until the temperature in the kettle reached 110 ° C. At this stage, a fluid and viscous photosensitive resin composition 2 was obtained. The photosensitive resin composition 2 had a Shore D hardness of 52 ° and an impact resilience of 30% after ultraviolet exposure.

Reference example 3
2. 2-methylpentamethylenediamine (MPDA) 2.1 parts, 1,4-bisaminopropylpiperazine (BAPP) 8.4 parts, polyethylene glycol hexamethylene diisocyanate reactant (HE-600) 46.6 parts and lactic acid 3. 7 parts and 13.0 parts of N-ethyltoluenesulfonic acid amide were placed in 60 parts of methanol and a heating and dissolving kettle with stirring, and after sufficient nitrogen substitution, the mixture was sealed and gradually heated to 65 ° C and stirred. After stirring for about 2 hours, 0.01 part of 1,4-naphthoquinone and 0.1 part of hydroquinone monomethyl ether were added and further stirred and dissolved for 30 minutes. Thereafter, 1.5 parts of glycidyl methacrylate (GMA) was further added and stirred, and then 6 parts of water, 0.3 part of ammonium sulfite, 0.1 part of oxalic acid, and 1.0 part of benzyldimethyl ketal as a photoinitiator. , Wako Pure Chemical Industries, Ltd. aluminum N nitrosophenylhydroxylamine Q1301 was dissolved in a very small amount of tetrahydrofuran and added, and glycerol dimethacrylate (Kyoeisha Chemical Co., Ltd. cross-linking agent Light Ester G101P) 22.7 parts, 1.0 part of a cross-linking agent epoxy ester 70PA was added and dissolved by stirring for 30 minutes. Next, the temperature was gradually raised to distill methanol and water, and the mixture was concentrated until the temperature in the kettle reached 110 ° C. At this stage, a fluid and viscous photosensitive resin composition 3 was obtained. The photosensitive resin composition 3 had a Shore D hardness of 55 ° after ultraviolet exposure and a resilience of 36%.

Reference example 4
2-methylpentamethylenediamine (MPDA) 2.9 parts, 1,4-bisaminopropylpiperazine (BAPP) 6.8 parts, polyethylene glycol hexamethylene diisocyanate reactant (HE-600) 45.4 parts and adipic acid 1 7 parts were placed in 100 parts of methanol and a heating and melting kettle equipped with a stirring blade, and after sufficient nitrogen substitution, the mixture was sealed and gradually heated to 65 ° C. with stirring. After stirring for about 2 hours, 0.03 part of 1,4-naphthoquinone and 0.1 part of hydroquinone monomethyl ether were added and further dissolved by stirring for 30 minutes. Thereafter, 2.5 parts of glycidyl methacrylate (GMA), 12 parts of water, 0.3 part of ammonium sulfite, 0.1 part of oxalic acid, 0.7 part of adipic acid, 1.0 part of benzyldimethyl ketal as a photoinitiator, glycerin 20.0 parts of dimethacrylate (Kyoeisha Chemical Co., Ltd. crosslinker light ester G101P) and 13.5 parts of epoxy ester 40EM were further added and dissolved by stirring for 30 minutes. Next, the temperature was gradually raised to distill methanol and water, and the mixture was concentrated until the temperature in the kettle reached 110 ° C. At this stage, a fluid and viscous photosensitive resin composition 4 was obtained. This photosensitive resin composition 4 had a Shore D hardness of 55 ° after ultraviolet exposure and a rebound resilience of 30%.

Reference Example 5
ε-Caprolactam 55.0 parts, N, N′-bis (γ-aminopropyl) piperazine adipate 40.0 parts, 1,3-bisaminomethylcyclohexane adipate 7.5 parts and water 100 parts are placed in a reactor. After sufficient nitrogen substitution, the mixture was sealed and gradually heated. When the internal pressure reached 10 kg / cm 2, water in the reactor was gradually distilled out and returned to normal pressure in 1 hour, and then reacted at normal pressure for 1.0 hour. The maximum polymerization temperature was 220 ° C. The obtained polymer obtained transparent light yellow polyamide 1 having a melting point of 140 ° C. and a specific viscosity of 2.00.

  50.0 parts of the obtained polyamide 1, 5.0 parts of N-ethyltoluenesulfonic acid amide, 0.03 part of 1,4-naphthoquinone, 50.0 parts of methanol, and 10 parts of water were added to a heated kettle with stirring. After mixing at 60 ° C. for 2 hours to completely dissolve the polymer, 38.1 parts of an acrylic acid adduct of trimethylolpropane triglycidyl ester, 2.5 parts of glycidyl methacrylate, 2.9 parts of methacrylic acid, hydroquinone monomethyl 0.1 part of ether, 0.3 part of ammonium sulfite, 0.1 part of oxalic acid and 1.0 part of benzyl dimethyl ketal were added and dissolved for 30 minutes. Next, the temperature was gradually raised to distill methanol and water, and the mixture was concentrated until the temperature in the kettle reached 110 ° C. At this stage, a fluid and viscous photosensitive resin composition 5 was obtained. This photosensitive resin composition 5 had a Shore D hardness of 55 ° after ultraviolet exposure and a rebound resilience of 25%.

Reference Example 6
Next, 20 μm of polyurethane adhesive layer was provided on a 250 μm polyester film. For the polyurethane adhesive layer, 80 parts by weight of polyester resin “Byron RV-300” manufactured by Toyobo Co., Ltd. was dissolved in 1940 parts by weight of a mixed solvent of toluene / methyl ethyl ketone = 80/20 (weight ratio) at 80 ° C. After cooling, 20 parts by weight of “Desmodur HL” of isocyanurate type polyisocyanate made by Sumitomo Bayer Urethane Co., Ltd. using hexamethylene diisocyanate and toluene diisocyanate as isocyanurate type polyisocyanate, triethylenediamine 0 as a curing catalyst 0.06 part by weight was added and stirred for 10 minutes. The adhesive layer composition solution thus obtained was applied onto a polyethylene terephthalate film having a thickness of 250 μm so as to have a film thickness of 20 μm, and dried at 100 ° C. for 3 minutes to obtain a support.

Examples 1-4, Comparative Example 1
Between the support obtained in Reference Example 6 and a polyester film of 125 μm thickness having a coating of 2 μm thick polyvinyl alcohol (AH-24, manufactured by Nippon Synthetic Chemical Co., Ltd.), in Reference Examples 1 to 5 The polyester film is laminated on the photosensitive layer with a laminator so that the obtained photosensitive resin compositions 1 to 5 are in contact with the photosensitive layer, and a sheet-like laminate 1 having a total thickness of 950 μm and a photosensitive layer thickness of 480 μm. ~ 5 was obtained. Each of these laminates was solidified into a plate shape at 30 ° C. under storage. Next, 24 hours later, each obtained laminate was heated at 103 ° C. for 3 minutes and stored for 7 days or more, and then photosensitive resin original plates (raw plates) 1 to 5 were obtained.

  Reliefs (photosensitive resin printing plates) 1 to 5 were prepared under the conditions of reproducing 175 L / i-2% halftone dots using the obtained photosensitive resin original plates 1 to 5, and the obtained printed materials respectively. Printing evaluation (measurement of halftone dot density). The results are shown in Table 1.

表１より明らかなように本発明印刷版（実施例１〜４）は、網点太りが小さく、シャープな刷り上がりの優れた印刷物が得られていることが判る。

As is apparent from Table 1, it can be seen that the printing plates of the present invention (Examples 1 to 4) are small in halftone dots and have excellent printed products with sharp prints.

  The photosensitive resin printing plate of the present invention having the above-described configuration can provide a printing plate excellent in reproducibility of fine independent points at the time of plate making and printing, as is clear from the above-mentioned examples. It is great to contribute to

Claims (2)

A photosensitive resin printing plate obtained from a photosensitive resin laminate having at least a support, a photosensitive resin layer, a protective layer, and a cover film, wherein the Shore D hardness of the photosensitive resin layer is 50 ° to 60 after exposure plate making. A photosensitive resin printing plate having a rebound resilience of 30% or more. The photosensitive resin printing plate according to claim 1, wherein at least one of the crosslinking agents contained in the photosensitive resin layer is glycerin dimethacrylate.