JP2021051209A - Photosensitive film for screen printing plate and method of manufacturing screen printing plate - Google Patents

Abstract

To provide a photosensitive film for a screen printing plate, which is excellent in solvent resistance and printing durability and exhibits little mask contamination after contact exposure, and to provide a method of manufacturing a screen printing plate.SOLUTION: The photosensitive film for a screen printing plate includes a protective layer and a photosensitive resin layer in this order on a support. The protective layer contains (A) an alkali-soluble resin, and the photosensitive resin layer contains (B) an acid-modified epoxy acrylate, (C) a blocked isocyanate compound, and (D) a photopolymerization initiator. The method of manufacturing a screen printing plate uses the photosensitive film for a screen printing plate.SELECTED DRAWING: Figure 1

Description

The present invention relates to a photosensitive film for a screen printing plate and a method for producing a screen printing plate, which are excellent in solvent resistance and printing resistance and have less mask contamination after close exposure.

In recent years, printed electronics that form electrodes using printing technology have attracted attention. Examples of the printing method include offset printing, gravure printing, inkjet printing, screen printing, etc. In particular, screen printing can form a fine pattern even on a circuit board having a wide range of printing targets and unevenness. Therefore, it is widely used for forming electrodes of touch panels and solar cells (Patent Document 1).

The conductive ink generally used for electrode formation is composed of metal fine particles, resins, and an organic solvent. Printing is performed on the base material by extruding this conductive ink from the screen printing plate on which the pattern is formed. The printed conductive ink pattern becomes an electrode wiring having high conductivity through a drying / firing step.

As a photosensitive resin composition for a screen printing plate, a photosensitive resin composition using a water-soluble polymer that can be developed with water is widely known. For example, a photosensitive resin composition obtained by emulsifying and dispersing a radically polymerizable compound in an aqueous solution of a polyvinyl alcohol-based water-soluble polymer in the presence of a sensitizer and a photopolymerization initiator (Patent Document 2), water resistance and an organic solvent. After exposing and developing a photosensitive resin composition containing a partially saponified vinyl acetate polymer containing a photocrosslinkable group for the purpose of increasing resistance, the component crosslinked by heat reacts with the hydrophilic group of the vinyl acetate polymer. It is characterized by having a method for making the polymer (Patent Document 3), an alkali-soluble acrylic copolymer, a polyfunctional acrylic acrylate monomer, a heat-crosslinkable compound (bifunctional or higher functional blocked isocyanate compound) that is crosslinked by heat, and a polymerization initiator. A photosensitive resin composition for plate making for screen printing (Patent Document 4) and the like have been proposed.

However, since the screen printing plate formed by using the conventional photosensitive resin composition has low resistance to the organic solvent contained in the conductive ink, the plate may swell or the screen may swell in the process of repeating the number of printings. It has been a problem that the desired printing durability cannot be obtained due to the printing plate falling off from the printing plate.

Further, in the photosensitive film for screen printing plate having a photosensitive resin layer containing the photosensitive resin composition for screen printing plate on the support, the support is removed after the photosensitive resin layer is pressure-bonded to the screen. The exposure process is performed from. At this time, the exposure may be performed with the mask in close contact with the photosensitive resin layer, but since the photosensitive resin layer has high adhesiveness, the photosensitive resin layer is transferred to the mask side. May cause mask contamination. As a countermeasure, a plate film forming member (Patent Document 5) in which an intermediate layer made of a water-soluble polymer is provided between the photosensitive resin layer and the support has been proposed.

However, the intermediate layer made of a water-soluble polymer provided between the photosensitive resin layer and the support has poor adhesion, and may be peeled off from the photosensitive resin layer when the support is removed. Further improvement was desired.

Japanese Unexamined Patent Publication No. 2013-219389 JP-A-2017-3912 Japanese Unexamined Patent Publication No. 2001-133996 Japanese Unexamined Patent Publication No. 2003-307833 Japanese Unexamined Patent Publication No. 2018-28676

An object of the present invention is to provide a photosensitive film for a screen printing plate and a method for producing a screen printing plate, which are excellent in solvent resistance and printing resistance and have less mask contamination after close exposure.

(1) In a photosensitive film for a screen printing plate having a protective layer and a photosensitive resin layer on a support in this order, the protective layer contains (A) an alkali-soluble resin, and the photosensitive resin layer is: A photosensitive film for a screen printing plate, which comprises (B) an acid-modified epoxy acrylate, (C) a blocked isocyanate compound, and (D) a photopolymerization initiator.

(2) Includes a step of laminating the photosensitive film for screen printing plate according to (1) above on a screen, a step of removing a support, a step of exposing a photosensitive resin layer in an image, an alkali developing step, and a heating step. How to make a screen printing plate.

The photosensitive film for screen printing plate of the present invention has a protective layer containing (A) an alkali-soluble resin (sometimes referred to as "component (A)") between the support and the photosensitive resin layer. Therefore, even if close contact exposure is performed with the support removed, contamination such as transfer of the photosensitive resin layer to the mask does not occur, and the screen printing plate is less likely to be chipped.

Further, in the present invention, the photosensitive resin layer is described as (B) acid-modified epoxy acrylate (may be described as "component (B)") and (D) photopolymerization initiator (described as "component (D)"). Since it contains (may be), a patterned cured film is formed by exposing it to an image. Then, alkaline development is performed to form a resist pattern, and then heat treatment is performed to obtain a blocked isocyanate group in the (C) blocked isocyanate compound (sometimes referred to as "component (C)"). A strong bond is formed by thermal cross-linking between the isocyanate group generated from the above and the carboxyl group and / or the hydroxyl group in the component (B), the resistance to the organic solvent contained in the conductive ink is improved, and the printing resistance is excellent. ..

It is sectional drawing which shows the structure of the photosensitive film for a screen printing plate of this invention.

Hereinafter, the present invention will be described.

The photosensitive film for screen printing plate of the present invention (“photosensitive film for screen printing plate” may be abbreviated as “photosensitive film”) has a protective layer on the support 1 as shown in FIG. 2 and the photosensitive resin layer 3 are provided in this order. Further, the protective film 4 may be provided on the photosensitive resin layer 3.

Without the protective layer 2, there arises a problem that the photosensitive resin layer 3 is transferred to the mask when close exposure is performed with the support 1 removed.

In the present invention, the protective layer 2 contains (A) an alkali-soluble resin. Examples of the component (A) include an alkali-soluble cellulose derivative and a carboxyl group-containing acrylic resin.

Examples of the alkali-soluble cellulose derivative include cellulose acetate phthalate, hydroxypropylmethyl cellulose phthalate, hydroxypropyl methyl cellulose acetate phthalate, and hydroxypropyl methyl cellulose acetate succinate.

Examples of the carboxyl group-containing acrylic resin include an acrylic polymer containing (meth) acrylate as a main component and copolymerizing it with an ethylenically unsaturated carboxylic acid. Further, other monomers having a copolymerizable ethylenically unsaturated group may be copolymerized.

Examples of the (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, and n. -Hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate , Lauryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2- (dimethylamino) ethyl (meth) acrylate, 2- (diethylamino) ethyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) Examples thereof include acrylates and 2,2,3,3-tetrafluoropropyl (meth) acrylates.

As the ethylenically unsaturated carboxylic acid, monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid are preferably used, and dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid, and anhydrides and half esters thereof are used. You can also do it. Of these, acrylic acid and methacrylic acid are particularly preferable.

Other monomers having a copolymerizable ethylenically unsaturated group include, for example, styrene, α-methylstyrene, p-methylstyrene, p-ethylstyrene, p-methoxystyrene, p-ethoxystyrene, p-. Examples thereof include chlorostyrene, p-bromostyrene, (meth) acrylonitrile, (meth) acrylamide, diacetone acrylamide, vinyl toluene, vinyl acetate, vinyl-n-butyl ether and the like.

The acid value (JIS-K0070: 1992) of the component (A) is preferably 30 to 500 mgKOH / g, more preferably 100 to 300 mgKOH / g. If the acid value is less than 30 mgKOH / g, the alkali development time tends to be long, while if it exceeds 500 mgKOH / g, the adhesion between the protective layer 2 and the photosensitive resin layer 3 may be deteriorated.

The mass average molecular weight of the component (A) is preferably 10,000 to 200,000, more preferably 10,000 to 150,000. If the mass average molecular weight is less than 10,000, it may be difficult to form the protective layer 2 in a film state, while if it exceeds 200,000, the solubility in an alkaline developer tends to deteriorate.

In the present invention, the protective layer 2 may contain a component other than the component (A), if necessary. Such components include urethane (meth) acrylate compounds, photopolymerizable monomers, solvents, thermosetting inhibitors, plasticizers, photocolorants, photodecolorizers, thermosetting inhibitors, fillers, defoamers. , Flame retardant, adhesion imparting agent, leveling agent, peeling accelerator, antioxidant, fragrance, thermosetting agent, water repellent, oil repellent, etc., each containing about 0.01 to 80% by mass. it can. These components may be used alone or in combination of two or more.

In the present invention, the blending ratio of the component (A) is preferably 20 to 95% by mass, more preferably 40 to 60% by mass, based on all the components of the protective layer 2. If the compounding ratio of the component (A) is less than 20% by mass, the alkali developability may decrease. If the blending ratio of the component (A) exceeds 95% by mass, the protective layer 2 is likely to be peeled off from the support 1, and the support 1 may be detached when the photosensitive film is cut.

In the present invention, the photosensitive resin layer 3 contains (B) an acid-modified epoxy acrylate, (C) a blocked isocyanate compound, and (D) a photopolymerization initiator.

As the component (B), an epoxy resin to which acrylic acid, methacrylic acid or the like is added, and further to which carboxylic acid or an anhydride thereof is added can be used. Examples of the epoxy resin include phenol novolac type, cresol novolac type, bisphenol A type, bisphenol F type, trisphenol type, tetraphenol type, phenol-xylylene type, glycidyl ether type and halogenated epoxy resins thereof. The acid anhydrides used include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, and phthalic anhydride. Chlorendic acid, methyltetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride and the like can be used.

The acid value of the component (B) affects the alkali development speed, the softness of the photosensitive resin layer 3, and the like. The acid value of the component (B) is preferably 40 to 120 mgKOH / g. If the acid value is less than 40 mgKOH / g, the alkaline development time tends to be long, while if it exceeds 120 mgKOH / g, the adhesion to the screen may be poor.

The mass average molecular weight of the component (B) is preferably 3,000 to 15,000. If the mass average molecular weight is less than 3,000, it may be difficult to form the photosensitive resin layer 3 before curing in a film state. On the other hand, if it exceeds 15,000, the solubility in an alkaline developer tends to deteriorate.

The component (C) is a compound obtained by reacting an isocyanate group of an isocyanate compound with a blocking agent, and is stable at room temperature, but when heated under certain conditions, the blocking agent is cleaved to form an isocyanate group. It is a compound that is generated. Examples of the blocking agent include phenols such as phenol, cresol, p-ethylphenol and p-tert-butylphenol, alcohols such as ethanol, butanol, ethylene glycol, methylcellsolve and benzyl alcohol, diethyl malonate, ethyl acetoacetate and the like. Active methylene-based, acetanilide, acid-amide-based such as acetamide, other imide-based, amine-based, imidazole-based, pyrazole-based, urea-based, carbamate-based, imine-based, holodoaldoxime, acetaldoxime, cyclohexanone oxime, etc. There are oxime-based, mercaptan-based, sodium bicarbonate-based, sulfite-based such as potassium bicarbonate, and lactam-based.

Examples of the isocyanate compound include 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, xylylene diisocyanate, 1,6-hexamethylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and 4,4'-methylenebis (cyclohexyl isocyanate). ), Trimethylhexanemethylene diisocyanate, isophorone diisocyanate, naphthalenediocyanate, trizine diisocyanate, lysine diisocyanate, methylcyclohexane-2,4-diisocyanate, methylcyclohexane-2,6-diisocyanate, 1,3- (isocyanatomethyl) cyclohexane, dimeric acid Examples thereof include diisocyanates and prepolymers such as adducts, biurets and isocyanurates thereof.

The components (D) include 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butane-1-one and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane. Aromatic ketones such as -1-one; 2-ethylanthraquinone, phenanthrenquinone, 2-tert-butyl anthraquinone, octamethylanthraquinone, 1,2-benz anthraquinone, 2,3-benz anthraquinone, 2-phenylanthraquinone, 2, Kinones such as 3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, etc. Benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether; benzoin compounds such as benzoin, methyl benzoin, ethyl benzoin; benzyl dimethyl ketal, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1 -Phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-1- {4- [4- (2-) Hydroxy-2-methylpropionyl) benzyl] phenyl} -2-methylpropan-1-one, 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) Phenyl] alkylphenones such as -1-butanone; acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide; 1, 2-octanedione, 1- [4- (phenylthio)-, 2- (o-benzoyloxime)], etanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl ]-, 1- (o-Acetyloxym) and other oxime esters; 2- (2'-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (2'-chlorophenyl) 4,5-di (Methenyl) imidazole dimer, 2- (2'-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (2'-methoxyphenyl) -4,5-diphenylimidazole dimer, 2 -(4'-methoxyfe 2,4,5-Triarylimidazole dimer such as Nyl) -4,5-diphenylimidazole dimer; aclysine derivatives such as 9-phenylaclysine, 1,7-bis (9,9'-acrydinyl) heptane N-phenylglycine, N-phenylglycine derivative; coumarin compounds; benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylicized benzophenone, 4-benzoyl-4'-methyldiphenylsulfide, Benzophenone compounds such as 3,3', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 4,4'-bis (dimethylamino) benzophenone, and 4,4'-bis (diethylamino) benzophenone Can be mentioned. The substituents on the aryl groups of the two 2,4,5-triarylimidazoles in the above 2,4,5-triarylimidazole dimer may give the same and symmetric compounds, or differently. Asymmetric compounds may be given. Further, a thioxanthone-based compound and a tertiary amine compound may be combined, such as a combination of diethyl thioxanthone and dimethylaminobenzoic acid. These are used alone or in combination of two or more. Among them, the imidazole dimer has high sensitivity and can be preferably used, and further, the 2- (2'-chlorophenyl) -4,5-diphenylimidazole dimer can be usefully used.

The photosensitive resin layer 3 of the present invention may contain components other than the above components (B) to (D), if necessary. Such components include crosslinkable monomers, sensitizers, thermosetting inhibitors, plasticizers, colorants (dye, pigment), photocolorants, thermal colorants, defoaming agents, flame retardants, stabilizers, etc. Adhesion-imparting agents, leveling agents, peeling accelerators, antioxidants, fragrances, thermosetting agents, water repellents, oil repellents and the like can be mentioned, and each can be contained in an amount of about 0.01 to 20% by mass. These components may be used alone or in combination of two or more.

In the present invention, the blending ratio of the component (B) is preferably 40 to 90% by mass, preferably 50 to 80% by mass, based on the total amount of the component (B), the component (C) and the component (D). More preferably. If the blending ratio of the component (B) is less than 40% by mass, the cross-linking after exposure is weak and the film property may be deteriorated. If it exceeds 90% by mass, the solvent resistance may decrease.

The blending ratio of the component (C) is preferably 10 to 40% by mass, more preferably 15 to 30% by mass, based on the total amount of the component (B), the component (C) and the component (D). preferable. If the compounding ratio of the component (C) is less than 10% by mass, the solvent resistance after heating may be insufficient. On the other hand, if it exceeds 40% by mass, the photocuring becomes insufficient and the resolution may be deteriorated.

The blending ratio of the component (D) is preferably 0.1 to 10% by mass, preferably 0.2 to 5% by mass, based on the total amount of the component (B), the component (C) and the component (D). More preferably. If the blending ratio of the component (D) is less than 0.1% by mass, the photopolymerizability may be insufficient. On the other hand, if it exceeds 10% by mass, the resolution may be deteriorated.

Hereinafter, a method for manufacturing the screen printing plate of the present invention will be described. In the method for producing a screen printing plate of the present invention, a step of laminating a photosensitive film having a protective layer 2 and a photosensitive resin layer 3 on the support 1 in this order, a step of removing the support 1, and a photosensitive It includes a step of exposing the resin layer 3 in an image, an alkali developing step, and a heating step.

In the method for producing a screen printing plate of the present invention, the photosensitive resin layer 3 of the photosensitive film having the protective layer 2 and the photosensitive resin layer 3 in this order is transferred onto the screen on the support 1.

From the viewpoint of suppressing heat shrinkage during laminating, it is desirable to use the support 1 having excellent thermal dimensions. Further, from the viewpoint of laminating on a flexible screen, it is desirable that the support 1 is a thin film having high followability. It may be a transparent film that transmits light, or it may be a white film or a colored film that blocks light. For example, polypropylene, polyethylene, polyester, polyimide, polycarbonate, polyphenylene sulfide, polyetherimide, knitted polyphenylene ether, urethane and the like can be used. Among them, the use of polyethylene terephthalate film, which is a kind of polyester, is advantageous for laminating suitability, peeling suitability, and smoothness, and is inexpensive, does not embrittle, has excellent solvent resistance, and is high. It is very easy to use due to its advantages such as tensile strength. The thickness of the support 1 is preferably 1 to 100 μm, more preferably 35 to 75 μm.

The method of forming the protective layer 2 on the support 1 can be performed by a coating method using an apparatus such as a roll coater, a comma coater, a gravure coater, an air knife, a die coater, or a bar coater. The thickness of the protective layer 2 is preferably 0.1 to 5 μm, more preferably 0.5 to 3 μm. If the protective layer 2 is too thick, problems such as deterioration of resolution and high cost may occur. On the contrary, if it is too thin, the adhesiveness may increase and the protective layer 2 may not be able to play a role.

The method of forming the photosensitive resin layer 3 on the protective layer 2 can be performed by a coating method using an apparatus such as a roll coater, a comma coater, a gravure coater, an air knife, a die coater, or a bar coater. The thickness of the photosensitive resin layer 3 is preferably 3 to 120 μm, more preferably 5 to 100 μm. If the photosensitive resin layer 3 is too thick, problems such as deterioration of resolution and high cost are likely to occur. On the contrary, if it is too thin, the adhesion to the screen tends to decrease.

The protective film 4 is provided to prevent oxygen inhibition, blocking, etc. of the photosensitive resin layer 3, and is provided on the photosensitive resin layer 3 on the opposite side of the support 1. It is preferable that the adhesive force between the photosensitive resin layer 3 and the protective film 4 is smaller than the adhesive force between the protective layer 2 and the support 1. Further, the protective film 4 having a small fish eye is preferable. Examples of the protective film 4 include a polyethylene film and a polypropylene film.

As a method for laminating the photosensitive film of the present invention on a screen, a thermocompression bonding treatment such as a heat laminating treatment is used. From the viewpoint of adhesion, the heating temperature is preferably 70 to 120 ° C. If the temperature is lower than 70 ° C, the adhesion to the screen may be poor, and if the temperature is higher than 120 ° C, the blocking agent of the component (C) contained in the photosensitive resin layer 3 starts to dissociate, which deteriorates the developability and the resolution. Not preferable.

Next, a step of exposing and developing the photosensitive resin layer 3 to form a pattern will be described. First, in the step of removing the support 1 and the step of exposing the photosensitive resin layer 3 in an image manner, a pattern-like exposure is performed on the photosensitive resin layer 3 from which the support 1 has been removed, and the exposed portion is cured. Let me. Although it is possible to expose without removing the support 1, it is desirable to expose with the support 1 removed in order to obtain high resolution. Specific examples of the exposure include close contact exposure using a mask. In the present invention, since the photosensitive film has the protective layer 2, mask contamination is unlikely to occur. In addition, a xenon lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, an ultra-high-pressure mercury lamp, a reflected image exposure using a UV fluorescent lamp as a light source, a proximity method, a projection method, and a scanning exposure can be mentioned. For scanning exposure, laser light sources such as UV laser, He-Ne laser, He-Cd laser, argon laser, krypton ion laser, ruby laser, YAG laser, nitrogen laser, dye laser, and excimer laser are used according to the emission wavelength. Examples thereof include a wavelength-converted scanning exposure, a scanning exposure using a liquid crystal shutter, a micromirror array shutter, and the like.

After the patterned exposure, an alkali developing step is carried out to remove the protective layer 2 containing the component (A), which is an unnecessary portion of the screen printing plate, and the photosensitive resin layer 3 of the non-exposed portion, and the photosensitive resin layer is cured. A screen printing plate containing the resin layer 3 is formed. As the alkaline developer used for development, for example, an aqueous solution of an inorganic alkaline compound can be used. Examples of the inorganic alkaline compound include carbonates and hydroxides such as lithium, sodium and potassium. The concentration of the inorganic alkaline compound in the alkaline developer is preferably 0.1 to 3% by mass, and an aqueous sodium carbonate solution of 0.1 to 3% by mass can be preferably used as the alkaline developer. A small amount of a surfactant, a defoaming agent, a solvent and the like can be appropriately mixed in the alkaline developer. Development processing methods include a dip method, a battle method, a spray method, brushing, scraping, and the like, and the spray method is the most suitable for the removal speed. The treatment temperature for alkaline development is preferably 15 to 35 ° C., and the spray pressure is preferably 0.02 to 0.3 MPa.

The heating step in the method for producing a screen printing plate of the present invention is carried out for the purpose of improving the adhesion of the photosensitive resin layer 3 to the screen, improving the solvent resistance, and the like. The heating temperature is preferably equal to or higher than the dissociation temperature of the blocking agent to be used, preferably 90 to 250 ° C, and more preferably 110 to 200 ° C. If the heating temperature is less than 90 ° C., the crosslinking reaction proceeds slowly, and if it exceeds 250 ° C., decomposition of other components may occur. The heating time is preferably 10 to 90 minutes.

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to this example.

(Examples 1 to 3 and Comparative Examples 1 to 7)
Each component shown in Table 1 was mixed to obtain coating liquids 1 and 2 for a protective layer. The unit of each component compounding amount in Table 1 is [parts by mass]. The obtained coating liquid is applied onto a polyethylene terephthalate (PET) film (support 1, trade name: T60 Lumirror (registered trademark), 75 μm thickness, manufactured by Toray Industries, Inc.) using a wire bar, and at 90 ° C. After drying for 2 minutes, the solvent component was removed, and a protective layer 2 having a thickness of 3 μm was provided on one side of the PET film.

In Table 1, the component (A) is as follows.

(A) Alkaline-soluble resin (A-1) Copolymerized resin obtained by copolymerizing methyl methacrylate / n-butyl acrylate / methacrylic acid at a mass ratio of 64/15/21 (mass average molecular weight 30,000).

Each component shown in Table 2 was mixed to obtain a coating liquid for a photosensitive resin layer. The unit of the blending amount of each component in Table 2 is [part by mass]. In Examples 1 to 3 and Comparative Examples 4 to 6, the obtained coating liquid for the photosensitive resin layer was applied onto the protective layer 2 coated with the protective layer coating liquid 1 using an applicator. , 80 ° C. was dried for 5 minutes to remove the solvent component, and a photosensitive resin layer 3 (thickness of 35 μm) was obtained on one side of the PET film. In Comparative Examples 1 to 3, a coating liquid for a photosensitive resin layer was applied onto a polyethylene terephthalate (PET) film (support 1, trade name: T60 Lumirror (registered trademark), 75 μm thickness, manufactured by Toray Industries, Inc.) using an applicator. The coating was applied and dried at 80 ° C. for 5 minutes to remove the solvent component, and a photosensitive resin layer 3 (thickness of 35 μm) was obtained on one side of the PET film. In Comparative Example 7, the obtained coating liquid for the photosensitive resin layer was applied onto the protective layer 2 coated with the protective layer coating liquid 2 using an applicator, and dried at 80 ° C. for 5 minutes. , The solvent component was removed, and a photosensitive resin layer 3 (thickness of 35 μm) was obtained on one side of the PET film. A polyethylene film (protective film 4, trade name: GF1, 30 μm thickness, manufactured by Tamapoli) was attached to three photosensitive resin layers to prepare a photosensitive film for a screen printing plate.

In Table 2, each component is as follows.

(B) Acid-modified epoxy acrylate (B-1) Acid-modified epoxy acrylate KAYARAD (registered trademark) UXE-3024 (trade name, Nippon Kayaku Co., Ltd., concentration 65% by mass)
(B-2) Acid-modified epoxy acrylate KAYARAD (registered trademark) ZAR-1035 (trade name, Nippon Kayaku Co., Ltd., concentration 65% by mass)
(B-3) Acid-modified epoxy acrylate KAYARAD (registered trademark) ZFR-1401H (trade name, Nippon Kayaku Co., Ltd., concentration 62% by mass)
(B-4) Acid-modified epoxy acrylate KAYARAD (registered trademark) CCR-1235 (trade name, Nippon Kayaku Co., Ltd., concentration 62% by mass)

(C) Blocked isocyanate compound (C-1) SUMIDUR (registered trademark) BL3175 (trade name, manufactured by Sumika Covestro Urethane Co., Ltd., base: 1,6-hexamethylene diisocyanate, blocking agent: methylethylketone oxime, concentration 75% by mass)
(C-2) Death module (DESMODUR, registered trademark) BL1100 (trade name, manufactured by Sumika Cobestrolethane, base: 2,6-tolylene diisocyanate, blocking agent: ε-caprolactam, concentration 100% by mass)
(C-3) Death module (DESMODUR, registered trademark) BL3370 (trade name, manufactured by Sumika Covestro Urethane Co., Ltd., base: 1,6-hexamethylene diisocyanate, blocking agent: active methylene, concentration 70% by mass)

(D) Photopolymerization Initiator (D-1): 2- (2'-Chlorophenyl) -4,5-diphenylimidazole dimer (D-2): 4,4'-bis (diethylamino) benzophenone (D-) 3): 2-Methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one

(E) Polymerizable monomer (E-1): SR399 (trade name, manufactured by Sartmer, dipentaerythritol pentaacrylate)

(F) Epoxy resin (F-1): N-680 (trade name, manufactured by DIC Corporation, cresol novolac type epoxy resin)

(G) Alkaline-soluble resin (G-1): 2-methacryloylethyl in a copolymerized resin obtained by copolymerizing benzyl acrylate / styrene / acrylic acid / 2-hydroxyethyl methacrylate at a molar ratio of 15/37/30/18. Copolymerized resin reacted with isocyanate (methacryloyl group 14.5 mol%, acid value 120 mgKOH / g, mass average molecular weight 45,000, concentration 25 mass%)

(H) Water-dispersible polymer (H-1): HA-10A (manufactured by Japan Coating Resin Co., Ltd., vinyl acetate emulsion, concentration 50% by mass)

Next, after peeling off the polyethylene film (protective film 4) from the photosensitive film produced above, a stainless steel mesh (screen, trade name: M-30, number of meshes: 360 / inch, manufactured by NBC Metal Mesh Co., Ltd.) is used. The photosensitive resin layer 3 was thermocompression bonded at 70 ° C. Subsequently, after peeling off the PET film (support 1), the above stainless steel mesh was passed through a mask having a test pattern of line / space = 100 μm / 100 μm using an exposure machine equipped with a 5 kW ultra-high pressure mercury lamp light source. The photosensitive resin layer 3 formed in the above was subjected to close exposure, and developed with a 1% by mass sodium carbonate aqueous solution at a liquid temperature of 30 ° C. under the condition of a spray pressure of 0.2 MPa for 30 seconds using a conveyor type developing machine. It was treated, washed with water, and dried. Then, it was heat-treated at 150 ° C. for 30 minutes. At this time, in Examples 1 to 3 and Comparative Examples 4 to 6, contamination due to the photosensitive resin layer 3 and lack of a printing plate could not be confirmed on the mask after exposure. On the other hand, in Comparative Examples 1 to 3 and 7, contamination by transfer of the photosensitive resin layer 3 to the mask was observed. In Comparative Example 7, when the PET film was peeled off, the protective layer 2 was peeled off from the photosensitive resin layer 3, and contamination due to transfer of the photosensitive resin layer 3 to the mask was observed even after the exposure step.

Next, the obtained screen printing plate was cut out, immersed in propylene glycol 1-monomethyl ether 2-acetylate at room temperature for 24 hours, and then dried at 40 ° C. for 24 hours to evaluate the solvent resistance. Examples 1 to 1 3. In Comparative Examples 1 to 3 and 7, there was no peeling from the screen, and the line / space shape was not changed from that before immersion. On the other hand, in Comparative Examples 4 to 6, the photosensitive resin layer 3 was peeled off from the screen during the solvent immersion, and the pattern shape could not be observed.

Using a screen printing plate having a line / space = 100 μm / 100 μm obtained by the same operation as above, the printing operation was carried out using the conductive silver paste as ink. After performing the printing work 50,000 times, the state of the screen printing plate was observed. As a result, in Examples 1 to 3 and Comparative Examples 1 to 3 and 7, the photosensitive resin layer 3 was not peeled off from the screen, and the screens were not peeled off. No film thickness reduction due to wear of the printing plate was also confirmed. In Comparative Example 4, the photosensitive resin layer 3 swelled immediately after the start of printing and peeled off from the screen, so that the printing operation could not be performed. In Comparative Examples 5 and 6, the photosensitive resin layer 3 was peeled off from the screen during the printing operation, and could not withstand 50,000 printings.

As described above, in the examples, it is possible to obtain a photosensitive film for a screen printing plate having excellent solvent resistance and printing resistance and less mask contamination after close exposure.

The method for producing a photosensitive film for a screen printing plate and a screen printing plate of the present invention can be suitably used for screen printing using an ink containing an organic solvent.

1 Support 2 Protective layer 3 Photosensitive resin layer 4 Protective film

Claims (2)

In a photosensitive film for screen printing plates having a protective layer and a photosensitive resin layer on the support in this order,
The protective layer contains (A) alkali-soluble resin and contains
A photosensitive film for screen printing plates, wherein the photosensitive resin layer contains (B) an acid-modified epoxy acrylate, (C) a blocked isocyanate compound, and (D) a photopolymerization initiator. A screen printing plate including a step of laminating a photosensitive film for a screen printing plate according to claim 1, a step of removing a support, a step of exposing a photosensitive resin layer to an image, an alkali developing step, and a heating step. Production method.

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