JP2009139683A - Photosensitive resin laminate for printing original plate and photosensitive resin original plate obtained from the laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to industrially manufacture photosensitive resin laminates for printing original plates, which are excellent in thickness precision and cause no warp, to consequently provide printing original plates which are excellently suitable for newspaper printing. <P>SOLUTION: Provided are (1) a photosensitive resin laminate which has at least a metallic base material, a synthetic rubber-based photosensitive resin layer and a cover film, and is 700 μm or smaller in thickness, wherein the metallic base material is 80-200 μm in thickness, and the cover film uses a film which is less than 0.1% in heat shrinkage coefficient at 100°C and is 75-188 μm in thickness; (2) a photosensitive resin laminate described in (1), wherein the cover film is a polyethylene terephthalate of 100-125 μm; (3) a photosensitive resin laminate described in (2) comprising a photosensitive resin composition, wherein a synthetic rubber-based photosensitive resin layer in the photosensitive resin laminate itself includes (A) at least two kinds of hydrophobic polymers obtained from a water-dispersible latex, (B) a photopolymerizable compound, (C) a photopolymerization initiator, and, in addition, (D) a hydrophilic polymer or the like; and (4) a photosensitive resin original plate for newspaper printing obtained from a photosensitive resin laminate described in (1)-(3). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a photosensitive resin laminate for a printing original plate used for newspaper printing applications, and in particular, a photosensitive resin laminate used for a water-developable photosensitive printing original plate for flexographic printing and a photosensitive property obtained therefrom. This relates to the resin original plate.

  Traditionally, newspaper printing has been performed by offset printing, but has had problems that are difficult to improve. First, since oil-based ink is used in offset printing, the solvent is released into the atmosphere during drying. For this reason, it is not preferable in that a load is applied to the environment and the human body. Further, since it is difficult to remove the ink solvent sufficiently even after drying, there is a problem that ink adheres when a newspaper reader touches a printed character. Furthermore, as a printing technique, the offset plate takes time to start printing such as transferring ink to a subject via a blanket roll or using immersion water. In addition, the paper used at that time had a large loss.

  Therefore, in recent years, flexographic printing has begun to be performed instead of offset printing. In flexographic printing, since water-based ink can be used, adhesion of ink after drying can be prevented. Also, flexographic printing is a system in which ink is directly placed on a plate material and transferred directly from the plate material to a printing material without using a roll, so that there is an advantage that the printing start-up time and cost can be reduced.

  In flexographic printing, a solvent-developed flexographic plate that is developed with an organic solvent is generally used. However, in the solvent developing plate, since the odor of the solvent is generated, the working environment is bad, and the developing waste liquid cannot be poured into the waste water, and the labor and cost for disposal are added. In response to these backgrounds, recent heightened environmental awareness, and the tailwinds of environmental regulations, various water-developable flexographic plates have been proposed. (For example, Patent Document 1)

As a water-developable flexographic plate, a phase 1 mainly composed of a hydrophobic polymer and a phase 2 mainly composed of a hydrophilic polymer are added to a flexographic plate material that can be developed with an aqueous developer and imparted resistance to water-based ink. There has been proposed a phase structure in which particles having a dispersed phase are used and a phase having a hydrophilic component and a hydrophobic component is a continuous phase (for example, Patent Document 2).
Japanese Patent Laid-Open No. 1-108542 Japanese Patent Laid-Open No. 03-136052

  On the other hand, in newspaper printing, the speed of the printing process is important from the mission of providing the latest information, and the printing speed is performed by high-speed printing. There is a demand for an original printing plate having mechanical strength that can withstand it. Also, the length of the plate preparation time is important as compared with the offset printing plate. Therefore, in order to shorten the process time for mounting the flexographic plate on the plate cylinder, a flexographic plate having a metal support is used.

On the other hand, a water-developable flexographic plate used for newspaper printing is preferably used since the image reproducibility and development time, that is, plate-making time, can be shortened, and the flexographic plate having a small total thickness is used. A main total thickness of 0.4 mm to 0.64 mm is used. In a photosensitive resin laminate having a total thickness of 700 μm or less and a thin photosensitive resin laminate having a total thickness of 700 μm or less, the cover film is manufactured at the time of manufacturing in which the photosensitive resin layer is calendered (laminated) between the cover film and the support. As a result of heat shrinkage, wrinkles are mixed into the photosensitive resin layer, and the thickness accuracy is likely to deteriorate. In addition, even when no wrinkles are mixed, warping occurs due to the difference in shrinkage due to heat between the upper and lower components in the cutting after the calendering (lamination), which causes the cutting after the calendering (lamination) and the next on the production line. When the sheet was sent to the process, the end of the sheet was caught by the edge of the cutting blade and the like, and process trouble was likely to occur.
On the other hand, in the printing plate manufacturing stage, when the photosensitive resin laminate in which the warp is generated is used, the plate making operation is poor, and the production of the photosensitive resin laminate excellent in flatness has been demanded.

  In view of the above problems, the present invention makes it possible to industrially produce a photosensitive resin laminate for a printing original plate having good thickness accuracy and no warp, and as a result, provides a printing original plate excellent in newspaper printing suitability. This is a problem.

In order to solve the problems of the present invention, it is important to make the heat shrinkage rate of the cover film very small. When the metal is used for the support of the photosensitive resin laminate, the inventors have hardly any heat shrinkage when the support is a metal, but the cover film has a surprisingly large heat shrinkage between 80 and 120 ° C. When calendering (laminating) the photosensitive resin layer, the cover film is found to cause wrinkles and warpage due to heat shrinkage, and the problem is solved by making the heat shrinkage rate at 100 ° C very small. I found it.
That is, the present invention relates to (1) a photosensitive resin laminate having at least a metal support, a synthetic rubber-based photosensitive resin layer and a cover film, wherein the thickness of the photosensitive resin laminate is 700 μm or less, and the metal support A photosensitive resin laminate having a thickness of 80 to 200 μm and a thickness of 75 to 188 μm having a heat shrinkage rate of less than 0.1% at 100 ° C. as the cover film. (2) The photosensitive resin laminate according to (1), wherein the cover film is 100 to 125 μm of polyethylene terephthalate. (3) The synthetic rubber-based photosensitive resin layer of the photosensitive tree laminate is (A) at least two hydrophobic polymers obtained from water-dispersed latex (B) a photopolymerizable compound, and (C) a photopolymerization initiator. The photosensitive resin laminate according to (2), further comprising (D) a photosensitive resin composition containing a hydrophilic polymer in addition to the above components. (4) A photosensitive resin original plate for newspaper printing, obtained from the photosensitive resin laminate of (1) to (3).

  By using the photosensitive resin laminate of the present invention and a printing original plate obtained therefrom, a newspaper printing original plate that can be stably manufactured even in the manufacturing process of the photosensitive resin laminate and can obtain high printing quality is obtained. Because it is possible to provide, it is great to contribute to the industry.

Hereinafter, an embodiment of the present invention will be described.
The photosensitive resin laminate of the present invention has a configuration in which a photosensitive resin layer and a cover film are sequentially laminated on a support. If necessary, an adhesive layer may be provided between the support and the photosensitive resin layer, and an anti-adhesion layer may be provided between the photosensitive resin layer and the cover film.

    In the present invention, a metal support is used so that it can be mounted on a printing cylinder of a newspaper printing press using an offset plate. Specific examples of the metal used for the support include aluminum, steel, titanium, nickel, zinc, lead, tin, and copper. Moreover, not only a pure metal but 2 or more types of alloys, plywood, and a metal oxide plate containing the said metal can also be used. In general, a support made of steel or aluminum having a relatively low cost and excellent plasticity is preferable. Furthermore, steel excellent in dimensional stability is particularly preferable.

    The thickness of the metal used for the support is 80 to 200 μm, and is preferably 100 to 200 μm from the handling workability and weight. A more preferable thickness is 150 to 200 μm. If the thickness is less than 80 μm, the support does not have a low waist and is likely to be deformed and bend easily. If the thickness exceeds 200 μm, the weight becomes heavy and workability is deteriorated.

   Moreover, in this invention, in order to adhere | attach a support body and the photosensitive resin layer, an adhesive layer can be provided between these two layers. The adhesive layer component is not particularly limited as long as it has sufficient adhesion that does not peel off during printing. As the component of the adhesive layer, for example, a binder polymer, an isocyanate compound, and other additives are preferable, and a binder polymer that is a main component is preferably a polymer having a functional group capable of reacting with an isocyanate group. Includes hydroxyl group, carboxyl group, amino group, mercapto group, etc., and as an oligomer or polymer having these in the main chain (including end groups) or side chain, specifically terephthalic acid, isophthalic acid, adipic acid It is obtained from an acid component such as sebacic acid and a glycol component such as ethylene glycol, diethylene glycol, neopentyl glycol, butanediol, 4,4′-di (2-hydroxyethoxyphenyl) 2,2′-propane, or caprolactone. Examples include polyester It is.

  The isocyanate compound in the adhesive layer is a compound having two or more isocyanate groups, such as 2,4- or 2,6-tolylene diisocyanate, 2,4- or 2,6-cyclohexane diisocyanate-1-methyl. , Naphthylene-1,5-diisocyanate, 1,4-tetramethylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, isopropylidenebis (cyclohexyl isocyanate), m- or p-xylylene diisocyanate 1,3- or 1,4-cyclohexanedimethylisocyanate, isophorone diisocyanate, lysine diisocyanate, bis (2-isocyanatoethyl) fumarate, 2,2,4-trimethylhexamate Range isocyanate, 3,3'-dimethoxy-4,4'-diphenyl diisocyanate, 2,4-tolylene dimer, tris (4-phenylisocyanate) thiophosphate, diphenyl ether 2,4,4'-triisocyanate, 2,4'- Examples thereof include trimer of tolylene diisocyanate.

   In the present invention, the adhesive layer preferably contains an antihalation agent. By this compound, photocuring of a portion that should be an unexposed portion in the past can be suppressed by ultraviolet rays reflected from the support metal during exposure, and the relief depth can be increased and a sharper printed image can be obtained. As an antihalation agent, it is necessary to have ultraviolet absorption around 360 nm, and a commercially available ultraviolet absorber can be used.

  Examples of the solvent for dissolving the raw materials include benzene organic solvents such as benzene and toluene, ketone organic solvents such as methyl ethyl ketone and acetone, ester solvents such as ethyl acetate, ethylene glycol solvents, dimethylamino formaldehyde, dimethylamino Examples include, but are not limited to, organic solvents such as acetamide.

   As the photosensitive resin layer of the present invention, a water-developable synthetic rubber-based photosensitive resin layer can be used, and a known photosensitive resin layer can be used. Preferred examples include (A) at least one elastomeric binder, (B) a photopolymerizable compound, and (C) a photopolymerization initiator. In addition to the above components, (D) a hydrophilic polymer, etc. It is the contained photosensitive resin composition.

  In the present invention, it is preferable to use a hydrophobic polymer obtained from a water-dispersed latex as the component (A) in the preferred rubber-based photosensitive resin layer. The photosensitive resin is capable of water development and has a low water swelling rate. A laminate can be obtained. Here, the water-dispersed latex is a polymer particle dispersed in water as a dispersoid, and additionally contains a surfactant.

  Specifically, as the hydrophobic polymer, polybutadiene latex, natural rubber latex, styrene-butadiene copolymer latex, acrylonitrile-butadiene copolymer latex, polychloroprene latex, polyisoprene latex, polyurethane latex, methyl methacrylate-butadiene. Water-dispersed latex polymers such as copolymer latex, vinylpyridine polymer latex, butyl polymer latex, thiocol polymer latex, and acrylate polymer latex, and other components such as acrylic acid and methacrylic acid are copolymerized with these polymers And the resulting polymer. Among these, an aqueous dispersion latex polymer containing a butadiene skeleton or an isoprene skeleton in the molecular chain is preferably used from the viewpoint of hardness and rubber elasticity. Specifically, polybutadiene latex, styrene-butadiene copolymer latex, acrylonitrile-butadiene copolymer latex, methyl methacrylate-butadiene copolymer latex, and polyisoprene latex are preferable.

  The hydrophobic polymer obtained from the water-dispersed latex is preferably present in the form of fine particles in order to improve developability. Here, “exists on fine particles” means, for example, that observation of morphology and phase distribution is performed using a scanning probe microscope SPM, and polymers exist as independent particles without fusing with each other. The hydrophobic polymer fine particles preferably have a form dispersed in the component (B) or the component (C).

  The photopolymerizable compound which is the component (B) of the present invention is preferably a photopolymerizable oligomer, and the photopolymerizable oligomer has an ethylenically unsaturated group bonded to the terminal and / or side chain of the conjugated diene polymer. The number average molecular weight is 1000 or more and 10,000 or less. Specifically, it refers to a compound having the following structure in the molecular structure.

  The conjugated diene polymer constituting the conjugated diene ethylenic polymer is composed of a homopolymer of a conjugated diene unsaturated compound or a copolymer of a conjugated diene unsaturated compound and a monoethylenically unsaturated compound. Examples of such a conjugated diene unsaturated compound homopolymer or a copolymer of a conjugated diene unsaturated compound and a monoethylenically unsaturated compound include a butadiene polymer, an isoprene polymer, a chloroprene polymer, a styrene-chloroprene copolymer, Acrylonitrile-butadiene copolymer, acrylonitrile-isoprene copolymer, methyl methacrylate-isoprene copolymer, acrylonitrile-isoprene copolymer, methyl methacrylate-isoprene copolymer, methyl methacrylate-chloroprene copolymer, acrylic acid Examples include methyl-butadiene copolymer, methyl acrylate-isoprene copolymer, methyl acrylate-chloroprene copolymer, acrylonitrile-butadiene-styrene copolymer, and acrylonitrile-chloroprene-styrene copolymer. . Of these, a butadiene polymer, an isoprene polymer, and an acrylonitrile-butadiene copolymer are preferable from the viewpoint of rubber elasticity and photocurability, and a butadiene polymer and an isoprene polymer are particularly preferable.

  The method for introducing the terminal and / or side chain ethylenically unsaturated group of the conjugated diene polymer is not particularly limited. For example, (1) a hydroxyl group-terminated conjugated diene polymer obtained using hydrogen peroxide as a polymerization initiator. Monoethylenically unsaturated carboxylic acid such as (meth) acrylic acid or the like is ester-bonded to the terminal hydroxyl group by dehydration reaction, or monoethylenically unsaturated carboxylic acid such as methyl (meth) acrylate or ethyl (meth) acrylate (2) Conjugated diene heavy compounds obtained by copolymerizing an ethylenically unsaturated compound containing an unsaturated carboxylic acid (ester) at least partly with a conjugated diene compound. Examples include a method of reacting ethylenically unsaturated alcohol such as allyl alcohol and vinyl alcohol with the coalescence. .

  The content of these photopolymerizable oligomers is preferably 1 to 200 parts by weight with respect to 100 parts by weight of component (A). If the amount is 1 part by weight or less, the raw plate becomes hard and development with an aqueous developer cannot be performed. If the amount is 200 parts by weight or more, the raw plate becomes too soft and handling properties are deteriorated.

  In the present invention, in order to increase the mechanical strength of the printing plate and improve the printing durability, it is preferable that at least one of the photopolymerizable oligomers is an alkyl methacrylate other than the above. In particular, the alkyl methacrylate preferably has 8 to 18 carbon atoms and is linear.

  Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isoamyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl Examples include alkyl (meth) acrylates such as (meth) acrylate, cycloalkyl (meth) acrylates such as cyclohexyl (meth) acrylate, alkoxyalkyl (meth) acrylates such as methoxyethyl (meth) acrylate, and phenoxyethyl (meth) acrylate. Particularly preferred are n-lauryl methacrylate, alkyl (C12-13) methacrylate, tridecyl methacrylate, alkyl (C12-15) methacrylate.

  The content of these alkyl methacrylates is preferably 1 to 50 parts by weight, particularly preferably 5 to 10 parts by weight with respect to 100 parts by weight of component (A). If it is less than 1 part by weight, the mechanical strength of the exposed plate is not sufficient, and if it exceeds 50 parts by weight, it bleeds out to the surface of the photosensitive resin composition layer, and the cover film becomes difficult to peel off.

  Moreover, the photopolymerization initiator of this invention adds a photoinitiator as (C) component. Any photopolymerization initiator can be used as long as it can polymerize a polymerizable carbon-carbon unsaturated group by light. Especially, what has the function to produce | generate a radical by self-decomposition or hydrogen abstraction by light absorption is used preferably. For example, benzoin alkyl ethers, benzophenones, anthraquinones, benzyls, acetophenones, diacetyls and the like. As a compounding quantity of a photoinitiator, the range of 0.1-50 weight part is preferable with respect to 100 weight part of (A) component. By setting it to 0.1 parts by weight or more, the image reproduction is good without reducing the starting efficiency. The amount of 50 parts by weight or less is preferable because the sensitivity is not too high and the exposure time can be easily controlled.

In the present invention, if necessary, a hydrophilic polymer may be blended as the component (D). Examples of the hydrophilic polymer include -COOH, -COOM (M is a monovalent, divalent or trivalent metal ion). Or a substituted or unsubstituted ammonium ion), a group having a hydrophilic group such as —OH, —NH ₂ , —SO ₃ H, or a phosphate ester group is preferable. Specifically, (meth) acrylic acid or a salt thereof is used. Polymer, copolymer of (meth) acrylic acid or its salt and alkyl (meth) acrylate, copolymer of (meth) acrylic acid or its salt and styrene, (meth) acrylic acid or its salt and vinyl acetate Copolymer, (meth) acrylic acid or its salt and acrylonitrile copolymer, polyvinyl alcohol, carboxymethylcellulose, polyacrylamide, hydroxy Ethylcellulose, polyethylene oxide, polyethyleneimine, polyurethane having -COOM group, polyureaurethane having -COOM group, include the polyamic acid and their salts or derivatives having a -COOM group. These may be used alone or in combination of two or more.

  The content of these hydrophilic polymers is preferably 0.1 to 50 parts by weight, particularly 0.1 to 30 parts by weight, based on 100 parts by weight of component (A). If it is less than 0.1 parts by weight, the development time is delayed with an aqueous developer, and if it exceeds 50 parts by weight, the swelling with respect to water increases and the water-based ink resistance deteriorates.

  In the present invention, when the component (D) is blended, the component (A) and the component (A) preferably have a common skeleton structure. For example, examples of the common skeleton structure include an acrylonitrile-butadiene structure and a butadiene structure. Etc.

  A plasticizer can be further added to the photosensitive resin composition of the present invention. The plasticizer is not particularly limited as long as it generally has a property of softening the plate material, but those having good compatibility with the components (A) and (D) are preferable. More preferred are polyene compounds which are liquid at room temperature and compounds having an ester bond. Examples of the polyene compound that is liquid at room temperature include liquid polybutadiene, polyisoprene, and maleated products and epoxidized products having their end groups or side chains modified. Examples of the compound having an ester bond include phthalic acid ester, phosphoric acid ester, sebacic acid ester, adipic acid ester, and polyester having a molecular weight of 1000 to 3000.

  When these plasticizer components are added, 0 to 100 parts by weight is preferable with respect to 100 parts by weight of component (A) from the viewpoint of obtaining sufficient strength as a solid plate before photocrosslinking.

  In order to increase the thermal stability of the photosensitive resin composition of the present invention, a conventionally known polymerization inhibitor may be added. Preferable polymerization inhibitors include phenols, hydroquinones, catechols and the like. These compounding amounts are generally used in the range of 0.001 to 5% by weight with respect to the total photosensitive resin composition.

  As other components, dyes, pigments, viscosity modifiers, antifoaming agents, ultraviolet absorbers, fragrances, anti-aggregation agents, surfactants, and the like can be added.

  Since the photosensitive resin composition of the present invention produces adhesiveness depending on its composition, in order to improve the contact property with the negative film overlaid thereon and to enable repeated use of the negative film, You may provide the adhesion prevention layer which can be developed by the water system on the surface. Specifically, as an anti-adhesion layer, polyamide-type, polyvinyl alcohol-type, cellulose-type ethylene oxide-type, polymer electrolyte-type, nylon-type resins, etc., having a thickness of 0.5 μm to 10 μm, optionally coated on a cover film Things can be used.

Next, the cover film used in the present invention will be described. The cover film used in the present invention needs to have a heat shrinkage rate of less than 0.1% at 100 ° C. in order to solve the problems of the present invention. When the support used for the photosensitive resin laminate is a metal, the inventors have almost no heat shrinkage because the support is a metal, but the cover film has a large heat shrinkage, so that it is sensitive between 80 and 120 ° C. Found that wrinkles and warpage occur due to heat shrinkage of the cover film when calendering (laminating) the photosensitive photosensitive resin layer, and the problem is that the heat shrinkage rate at 100 ° C. is made smaller than a specific value. Settled. The present invention pays attention to the directionality of the film, and it is important that the heat shrinkage rate in the machine direction (MD) and the transverse direction (TD) is less than 0.1%.
The cover film provided on the photosensitive resin laminate of the present invention is made of a thermoplastic resin film, protects the photosensitive resin composition layer, and further needs to be peeled off when the printing plate is prepared. Specific examples of the cover film include a polyethylene terephthalate film, a polyethylene film, a polypropylene film, and a polystyrene film. Among them, a polyethylene terephthalate film having a low thermal shrinkage at 100 ° C. is preferable. For these films, a plain film or a matte film having a surface roughness Ra = 0.01 to 2.00 μm is used. The thickness of the film is preferably 75 to 188 μm, more preferably 100 to 125 μm. If the film thickness is less than 75 μm, the film strength is insufficient and the molded photosensitive resin composition laminate is easily deformed, and the function of protecting the photosensitive resin composition layer from external force is insufficient. On the other hand, if it exceeds 188 μm, the film strength is too strong, and therefore, it is easy to cause peeling between the photosensitive resin layer at the time of cutting.

  The cover film used in the present invention is characterized in that the heat shrinkage rate of the cover film at 100 ° C. is less than 0.1% in both the width direction and the flow direction with respect to the film roll. When the thermal shrinkage rate of the cover film exceeds 0.1%, problems such as warpage and wrinkles occur as a laminate due to the thermal shrinkage that occurs during the heat calendering process, leading to printing quality due to the manufacturing process, plate making process, and thickness variation. It is not preferable because of the influence of.

  As a method for obtaining a cover film having a heat shrinkage rate of less than 0.1% at 100 ° C. used in the present invention, it can be obtained by an annealing treatment in which a high temperature treatment is performed in a relaxed state after the film is stretched. Is preferably about 10 ° C. below the melting point of the resin. For example, in the case of a polyethylene terephthalate film, the treatment is preferably performed at around 240 ° C.

The photosensitive resin composition of this invention can be manufactured by mixing each component. As the means, it is possible to form a layer having a desired thickness by hot press molding or extrusion molding after mixing the resin composition using an extruder or a kneader. The support and the anti-adhesion layer can be brought into close contact with the photosensitive layer by roll lamination after sheet molding. A highly sensitive photosensitive layer can also be obtained by heating and pressing after lamination.
The thickness of the photosensitive layer varies depending on the printing machine, but is generally preferably 200 μm or more. If it is 200 μm or less, the ink adheres to the surface of the support and causes ink stains.

  The photosensitive resin composition laminate of the present invention has a thickness of 700 μm or less. When the thickness exceeds 700 μm, warpage when cutting into a sheet is suppressed by the weight of the photosensitive resin composition itself, and process troubles can be avoided.

  Examples of the active light source used for photocuring the photosensitive resin composition of the present invention include a low-pressure mercury lamp, a high-pressure mercury lamp, an ultraviolet fluorescent lamp, a carbon arc lamp, a xenon lamp, a zirconium lamp, and sunlight. After the photosensitive resin composition of the present invention is irradiated with light through a transparent image carrier to form an image, a non-irradiated portion is removed (developed) using an aqueous developer to obtain a relief (printing plate).

  The aqueous developer referred to in the present invention is prepared by blending water with a nonionic or anionic surfactant, and if necessary, a pH adjusting agent, a cleaning accelerator and the like. Specific examples of the nonionic surfactant include polyoxyalkylene alkyl or alkenyl ether, polyoxyalkylene alkyl or alkenyl phenyl ether, polyoxyalkylene alkyl or alkenyl amine, polyoxyalkylene alkyl or alkenyl amide, ethylene oxide / propylene oxide There are block appendages. Specific examples of the anionic surfactant include linear alkylbenzene sulfonate having an alkyl having an average carbon number of 8 to 16, an α-olefin sulfonate having an average carbon number of 10 to 20, an alkyl group or an alkenyl group. A dialkyl sulfosuccinate having 4 to 10 carbon atoms, a sulfonate of a fatty acid lower alkyl ester, an alkyl sulfate having an average carbon number of 10 to 20, a linear or branched alkyl or alkenyl group having an average carbon number of 10 to 20 And alkyl ether sulfates having an average of 0.5 to 8 moles of ethylene oxide, saturated or unsaturated fatty acid salts having an average carbon number of 10 to 22 and the like.

  Examples of the PH adjuster include sodium borate, sodium carbonate, sodium silicate, sodium metasilicate, sodium succinate, sodium acetate, and the like. Sodium silicate is preferred because it is easily dissolved in water. Further, although there is a cleaning aid, the cleaning ability is enhanced by using it together with the surfactant and the pH adjusting agent. Specific examples include amines such as monoethanolamine, diethanolamine and triethanolamine, ammonium salts such as tetramethylammonium hydroxide, and paraffinic hydrocarbons. These are used by being added and mixed with water in an appropriate amount in the range of 0.1 to 50% by weight, preferably 1 to 10% by weight. After development, the plate is generally dried in an oven at about 60 ° C. for 15 to 120 minutes.

  Depending on the composition of the photosensitive resin composition of the present invention, stickiness may remain on the plate surface even after drying is finished. In that case, stickiness can be removed by a known surface treatment method. As the surface treatment method, an exposure treatment with an actinic ray having a wavelength of 300 nm or less is desirable.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely using an Example, this invention is not limited to these Examples. In addition, the photosensitive resin composition in an Example was prepared in the following procedure.

  As an elastomeric binder as component (A), hydrophobic polymer (α): acrylonitrile-butadiene latex (Nipol SX1503 nonvolatile content 42%, manufactured by Nippon Zeon Co., Ltd.) 20 parts by weight, hydrophobic polymer (β): butadiene Latex (Nipol LX111NF non-volatile content 55% Nippon Zeon Co., Ltd.) 36 parts by weight, (B) component, lauryl methacrylate (Light Ester L Kyoeisha Chemical Co., Ltd.) 4 parts by weight, trimethylolpropane trimethacrylate 4 parts by weight , 12 parts by weight of oligobutadiene acrylate (ABU-2S manufactured by Kyoeisha Chemical Co., Ltd.), 1 part by weight of photopolymerization initiator as component (C), hydrophilic polymer as component (D) (PFT-3 25% nonvolatile content) Kyoeisha Chemical Co., Ltd.) 12 parts by weight, as a plasticizer, conjugated diene oligomer (B2000, Nippon Petrochemical Co., Ltd.) 6 layers 1 part by weight, 0.1 part by weight of hydroquinone monomethyl ether as a polymerization inhibitor was mixed in a container together with 5 parts by weight of toluene, and then kneaded at 105 ° C. using a pressure kneader, and then toluene and water were decompressed. The photosensitive resin composition was obtained by removing.

Moreover, the evaluation in an Example was implemented as follows.
(1) Entrapment of production process line: Sample size of photosensitive resin laminate The presence or absence of engagement when a sample having a width of 2 cm and a length of 15 cm passes the minimum gap height of 15 mm of the production process line was determined.
(2) Heat shrinkage rate: Evaluation was performed by the dimensional change measurement method of JIS2318. The MD direction of the film is the vertical direction, and the TD direction is the horizontal direction.
(3) Total thickness variation: The prepared photosensitive resin laminate was allowed to stand for 24 hours to solidify, and then the thickness in the molding width direction of the photosensitive resin laminate was measured. The thickness was measured with a dial gauge (TM-1201, manufactured by Teclock Co., Ltd.) at n = 5, and the difference between the maximum value and the minimum value was defined as the total thickness variation.
(4) Presence / absence of wrinkles: After the laminate was prepared and cut to a length of 1000 mm, the presence / absence of wrinkles was visually determined.
(5) Warpage presence / absence: After making a laminate, it was cut into A2 size, and the presence / absence of warpage was visually determined.

Example 1
A support in which a polyester adhesive layer is coated on a 170 μm-thick steel plate with a photosensitive resin composition, and an anti-adhesion layer (polyvinyl alcohol) on a polyethylene terephthalate film (polyester film E5000 100 μm thickness manufactured by Toyobo Co., Ltd.) Is coated with a coated film (so that the adhesive layer and the anti-adhesion layer are in contact with the photosensitive resin composition), and is pressed with a heat press machine at 100 ° C. and a pressure of 100 kg / cm ² for 15 minutes to obtain a thickness of 0. A 4 mm photosensitive resin laminate was produced.
The evaluation results are shown in Table 1. By using a cover film having a small heat shrinkage rate, there was no fouling or warpage, and there was no catching in the production process line.

Example 2
A photosensitive resin laminate was prepared in the same manner as in Example 1 except for polyethylene terephthalate film (polyester film E5000 125 μm thickness manufactured by Toyobo Co., Ltd.).
The evaluation results are shown in Table 1. By using a cover film having a small heat shrinkage rate, there was no fouling or warpage, and there was no catching in the production process line.

Example 3
A photosensitive resin laminate was prepared in the same manner as in Example 1 except for polyethylene terephthalate film (polyester film HS 125 μm thickness manufactured by Teijin Limited).
The evaluation results are shown in Table 1. By using a cover film having a small heat shrinkage rate, there was no fouling or warpage, and there was no catching in the production process line.

Example 4
A photosensitive resin laminate was prepared in the same manner as in Example 1 except that 150 μm aluminum was used as the support. The evaluation results are shown in Table 1. By using a cover film having a small heat shrinkage rate, there was no fouling or warpage, and there was no catching in the production process line.

Example 5
A photosensitive resin laminate was prepared in the same manner as in Example 1 except that 150 μm aluminum was used as the support. The evaluation results are shown in Table 1. By using a cover film having a small heat shrinkage rate, there was no fouling or warpage, and there was no catching in the production process line.

Example 6
A photosensitive resin laminate was prepared in the same manner as in Example 1 except for polyethylene terephthalate film (polyester film E5000, 188 μm thickness, manufactured by Toyobo Co., Ltd.).
The evaluation results are shown in Table 1. By using a cover film having a small heat shrinkage rate, there was no fouling or warpage, and there was no catching in the production process line.

Comparative Example 1
The photosensitivity obtained in the same manner as in Example 1 except for a 100 μm polyethylene terephthalate film (SKC polyester film SH71S 100 μm thickness) having a large heat shrinkage ratio of 0.15% in the MD direction and 0.05% in the TD direction. A resin laminate was produced. Although the evaluation results are shown in Table 2, warpage occurred in the laminated body and warpage occurred in the cut laminated body, and the product was caught in the production process line, resulting in poor productivity. Further, although the laminate was used as a printing original plate, it was a printing original plate with poor quality due to warpage and poor plate-making preparation workability and large thickness fluctuation.

Comparative Example 2
In Comparative Example 1, the photosensitive resin laminate obtained in the same manner except that the thickness was 1.14 mm with a heat press so that the photosensitive resin laminate had a thickness of 1.14 mm. The weight of the sheet caused little warpage of the sheet, and there was no catching of the production process line. However, wrinkles were mixed in the laminate and the thickness variation increased, and it was not usable as a printing original plate.

Comparative Example 3
A photosensitive resin laminate obtained in the same manner as Example 1 except that a polyethylene terephthalate film (Toyobo Co., Ltd. E5000) having a thickness of 250 μm was used as a cover film. The evaluation results are shown in Table 2, but by using a cover film having a small heat shrinkage rate, there was no fouling or warpage, and there was no catch in the production process line. However, peeling occurred between the cover film and the photosensitive resin layer by 5 mm from the outermost section at the time of cutting, and the laminate had poor quality.

Comparative Example 4
A photosensitive resin laminate was prepared in the same manner as in Example 1, except that the cover film was a polyethylene terephthalate film (Toyobo Co., Ltd. E5000) having a thickness of 50 μm. Although the evaluation results are shown in Table 2, there was no catch in the production process line because warpage did not occur. However, wrinkles were mixed in the laminate during the calendering process for producing the laminate, and the resulting laminate had a thin cover film, resulting in dents on the film surface, and only a poor-quality laminate was obtained.

Comparative Example 5
A photosensitive resin laminate was prepared in the same manner as in Example 1 except for polyethylene terephthalate film (polyester film SH71S 100 μm thickness manufactured by SKC). The heat shrinkage rate of the cover film used was 0.15 in the MD direction and 0.05 in the TD direction, and was a film having a large shrinkage rate in the MD direction. The evaluation results are shown in Table 1. As a result, warpage occurred in the cut laminated body and warpage occurred in the cut laminated body, and the product was caught in the production process line, resulting in poor productivity. Further, although the laminate was used as a printing original plate, it was a printing original plate with poor quality due to warpage and poor plate-making preparation workability and large thickness fluctuation.

As described above, the photosensitive resin assembly laminate of the present invention having such a configuration can reduce deformation due to heat, can be developed with a water-based developer without causing troubles with little warpage on the production process line, and water-based ink. It can be used for a flexographic printing original plate for newspapers having good resistance to image and good image reproducibility.

Claims (4)

  In a photosensitive resin laminate having at least a metal support, a synthetic rubber-based photosensitive resin layer and a cover film, the thickness of the photosensitive resin laminate is 700 μm or less, and the metal support is 80 to 200 μm. A film having a thickness of 75 to 188 μm and having a heat shrinkage rate of the cover film at 100 ° C. of less than 0.1% is used as the cover film.   The photosensitive resin laminate according to claim 1, wherein the cover film is polyethylene terephthalate having a thickness of 100 to 125 μm.   The synthetic rubber-based photosensitive resin layer of the photosensitive tree laminate includes (A) at least two hydrophobic polymers obtained from water-dispersed latex (B) a photopolymerizable compound, and (C) a photopolymerization initiator, Moreover, in addition to said component, it consists of the photosensitive resin composition containing (D) hydrophilic polymer etc., The photosensitive resin laminated body of Claim 2 characterized by the above-mentioned.   A photosensitive resin original plate for newspaper printing, which is obtained from the photosensitive resin laminate according to claim 1.