JP5643416B1 - Manufacturing method of coated wiring board - Google Patents

Abstract

In forming a film on a wiring board, regions having different colors are formed simultaneously with the formation of the film. A coating film comprising a composition containing a photopolymerizable compound, a photopolymerization initiator, a resin having a carboxyl group, and an organic compound having a melting point and not having photopolymerizability is formed on a wiring board. To do. The coated film is exposed and then developed, and further heated. The temperature of the coating film is maintained at a temperature lower than the melting point of the organic compound from the formation of the coating film to the completion of the exposure. At the time of exposure, the first part of the coating film is irradiated with light, the second part is irradiated with light at a low exposure amount, and the third part is not irradiated with light. The heating temperature during heating of the coating film satisfies the relationship of Th ≧ Tm-30 (Th (° C.) is the heating temperature of the coating film, and Tm is the melting point of the organic compound). [Selection] Figure 1

Description

The present invention relates to a method for producing a coated wiring board.

  A coating such as a solder resist is formed on a wiring board such as a wiring board in order to protect the wiring and prevent a short circuit when mounting components. In addition, the wiring board may be marked with characters, symbols or the like for displaying product information or the like. The marking is performed, for example, by applying a marking paste containing an inorganic component and an organic component and then firing (see Patent Document 1).

  Conventionally, when marking is performed on a coated wiring board including a wiring board and a coating film covering the wiring board, it is necessary to add a process only for marking after the formation of the coating film. That is, for example, after forming a film on a wiring board, it is necessary to apply a marking paste having a color different from this film on the film by screen printing or the like, and further to heat the marking paste. This leads to a decrease in the production efficiency of the wiring board.

  The reason why the film formation and the marking need to be performed separately is that the conventional film has a single color.

JP 2002-173629 A

The present invention has been made in view of the above reasons, and in obtaining a coated wiring board comprising a wiring board and a coating film covering the wiring board, the manufacture of a coated wiring board capable of forming regions of different colors on the coating film It aims to provide a method.

The method for producing a coated wiring board according to the first aspect of the present invention is a method for producing a coated wiring board comprising a wiring board and a coating covering the wiring board,
<a> A film-forming composition containing a photopolymerizable compound, a photopolymerization initiator, a resin having a carboxyl group, and an organic compound having a melting point and not having photopolymerizability is disposed on the wiring board. In the process of forming a coating film,
<B> a step of exposing the coating film; <c> a step of developing the exposed coating film with an alkaline developer; and <d> heating the coating film after development to form the coating film. Including steps,
The temperature of the coating film is maintained at a temperature lower than the melting point of the organic compound from the time when the coating film is formed by the step <a> to the time when the exposure in the process <b> is completed. ,
In the step <b>, the first part of the coating film is irradiated with light, and the second part different from the first part of the coating film has an exposure amount that is higher than that of the first part. Irradiate the light so as to be lower, do not irradiate the third part different from the first part and the second part in the coating film,
The heating temperature of the coating film in the step <d> is T _h ≧ T _m -30 (where T _h (° C.) is the heating temperature of the coating film, and T _m is the melting point of the organic compound. It is characterized by satisfying a certain relationship.

  The method for producing a coated wiring board according to the second aspect of the present invention is characterized in that, in the first aspect, the ratio of the organic compound is in the range of 1 to 65 mass% with respect to the solid content. .

  The method for manufacturing a coated wiring board according to a third aspect of the present invention is characterized in that, in the first or second aspect, the organic compound has a melting point in the range of 100 to 230 ° C.

  The method for producing a coated wiring board according to a fourth aspect of the present invention is the method according to any one of the first to third aspects, wherein the organic compound is selected from the group consisting of a crystalline epoxy compound and a dicarboxylic acid. It contains the above compound, It is characterized by the above-mentioned.

  The method for producing a coated wiring board according to a fifth aspect of the present invention is the method according to any one of the first to fourth aspects, wherein the film-forming composition is contained in the photopolymerization initiator and the organic compound. It is characterized by containing the compound contained in.

  In the method for manufacturing a coated wiring board according to the sixth aspect of the present invention, in any one of the first to fifth aspects, the resin having a carboxyl group has a carboxyl group and does not have photopolymerization property. It is characterized by containing a resin.

  The method for producing a coated wiring board according to a seventh aspect of the present invention is the method according to any one of the first to sixth aspects, wherein the resin having a carboxyl group has a carboxyl group and an ethylenically unsaturated group. It contains a compound contained in the photopolymerizable compound.

  In the method for producing a coated wiring board according to an eighth aspect of the present invention, in any one of the first to seventh aspects, the photopolymerizable compound contains a monomer having an ethylenically unsaturated group. Features.

  The method for producing a coated wiring board according to a ninth aspect of the present invention is characterized in that, in any one of the first to eighth aspects, the film forming composition contains a colorant.

  In the method for producing a coated wiring board according to a tenth aspect of the present invention, in any one of the first to eighth aspects, the film-forming composition does not contain a colorant, or the colorant is solid. It contains by the ratio of 0.04 mass% or less with respect to quantity.

  The method for manufacturing a coated wiring board according to an eleventh aspect of the present invention is the method for producing a coated wiring board according to any one of the first to tenth aspects, wherein the first portion is exposed to the first portion in the step <b>. The ratio of the exposure amount of the second part is in the range of 1 to 75%.

  The film forming composition according to the twelfth aspect of the present invention is a film forming composition used in the method for producing a coated wiring board according to any one of the first to eleventh aspects, and is photopolymerizable. It contains a compound, a photopolymerization initiator, a resin having a carboxyl group, and an organic compound having a melting point and not having photopolymerizability.

  The film forming composition according to the thirteenth aspect is characterized in that, in the twelfth aspect, the ratio of the organic compound is in the range of 1 to 65% by mass with respect to the solid content.

  The film forming composition according to a fourteenth aspect is characterized in that, in the twelfth or thirteenth aspect, the organic compound has a melting point in the range of 100 to 230 ° C.

  The film forming composition according to a fifteenth aspect is the film forming composition according to any one of the twelfth to fourteenth aspects, wherein the organic compound is one or more compounds selected from the group consisting of a crystalline epoxy compound and a dicarboxylic acid. It is characterized by containing.

  The film forming composition according to a sixteenth aspect is characterized in that, in any one of the twelfth to fifteenth aspects, the photopolymerizable compound contains a monomer having an ethylenically unsaturated group.

  The film forming composition according to a seventeenth aspect is the photopolymerizable compound according to any one of the twelfth to sixteenth aspects, wherein the resin having a carboxyl group has a carboxyl group and an ethylenically unsaturated group. It is characterized by containing the compound contained in.

  In the film forming composition according to an eighteenth aspect, in any one of the twelfth to seventeenth aspects, the resin having a carboxyl group contains a resin having a carboxyl group and no photopolymerization. It is characterized by that.

  The film forming composition according to the nineteenth aspect is characterized in that, in any one of the twelfth to eighteenth aspects, a colorant is contained.

  The film-forming composition according to the twentieth aspect is any one of the twelfth to eighteenth aspects, does not contain a colorant, or the ratio of the colorant to 0.04% by mass or less based on the solid content. Contains.

  According to the method for manufacturing a coated wiring board according to the present invention, when the coating film after exposure and development is heated, bubbles are formed in the first portion. On the other hand, in the second portion where the exposure amount at the time of exposure is lower than that of the first portion, no bubbles are formed even when heated, or bubbles are formed, but the ratio of the bubbles is the first portion. Lower than part. For this reason, the light transmittance of the hardened | cured material of the 1st part in a film becomes lower than the hardened | cured material of a 2nd part. Thereby, the area | region from which a color mutually differs can be formed in a film only by varying partially the exposure amount at the time of exposure.

It is general | schematic sectional drawing which shows the manufacturing method of a coated wiring board in one Embodiment of this invention. It is general | schematic sectional drawing which shows the manufacturing method of a coated wiring board in one Embodiment of this invention. It is general | schematic sectional drawing which shows the manufacturing method of a coated wiring board in one Embodiment of this invention.

  The film forming composition in the present embodiment will be described.

  The film-forming composition contains a photopolymerizable compound, a photopolymerization initiator, a resin having a carboxyl group, and an organic compound having a melting point and not having photopolymerizability (hereinafter referred to as a specific organic compound).

  In the present embodiment, in manufacturing a coated wiring board comprising a wiring board and a coating covering the wiring board, a coating film is formed by disposing the coating forming composition on the wiring board, and then The coating film is exposed, subsequently the exposed coating film is developed with an alkaline solution, and then the developed coating film is heated to form a coating film. The coating is provided as a solder resist, for example.

  Furthermore, in this embodiment, the temperature of the coating film is maintained at a temperature lower than the melting point of the specific organic compound from the time when the coating film is formed until the time when the exposure of the coating film is completed.

  Furthermore, in this embodiment, when exposing the coating film, the first portion of the coating film is irradiated with light, and the second portion different from the first portion of the coating film is exposed more than the first portion. Light is irradiated so that the amount is low, and light is not irradiated to a third portion different from the first portion and the second portion in the coating film.

  The exposure amount in the first portion may be uniform, and a plurality of portions having different exposure amounts may exist in the first portion. Moreover, when irradiating light to a 2nd part, the exposure amount in a 2nd part may be uniform, and the several part from which an exposure amount mutually differs may exist in a 2nd part.

Furthermore, in this embodiment, when heating the coating film, the heating temperature of the coating film is T _h ≧ T _m -30 (where T _h (° C.) is the heating temperature of the coating film, and T _m is a specific value. Which is the melting point of the organic compound). That is, the heating temperature when heating the coating film is equal to or higher than the temperature obtained by subtracting 30 ° C. from the melting point of the specific organic compound. In other words, the melting point of the specific organic compound is equal to or lower than the temperature obtained by adding 30 ° C. to the heating temperature when heating the coating film.

For this reason, in this embodiment, when the coating film after exposure and development is heated, bubbles are formed in the first portion. On the other hand, in the second portion, no bubbles are formed even when heated, or bubbles are formed, but the ratio of the bubbles is lower than that in the first portion. For this reason, the light transmittance of the hardened | cured material (1st area | region) of the 1st part in a film becomes lower than the hardened | cured material (2nd area | region) of a 2nd part. Further, light scattering is more likely to occur in the first region than in the second region.
For this reason, for example, when the composition for forming a film contains a colorant, the appearance color of the first region is mainly the color of the colorant, whereas the appearance color of the second region is that of the colorant. The color and the color of the surface of the wiring board are mixed. In addition, when the film-forming composition does not contain a colorant or contains a colorant but its proportion is small, the appearance color of the first region appears white due to light scattering by bubbles, The second area is transparent, and the color of the surface of the wiring board that is the base can be seen through the second area. Therefore, regions having different colors can be formed on the film only by partially varying the exposure amount during exposure.

  The effect of this embodiment is presumed to occur for the following reason.

  Since the first portion is irradiated with light during the exposure of the coating film, it contains a polymer produced by the photopolymerization reaction of the photopolymerizable compound. When the coating film is heated in this state, the specific organic compound in the coating film melts, and the coating film tends to deform. However, since the first part contains a polymer, the specific organic compound melts. Less likely to follow and deform. For this reason, it is considered that bubbles are generated in the first portion. On the other hand, the second part does not contain a polymer of a photopolymerizable compound, or the ratio of this polymer is lower than that of the first part. For this reason, when the coating film is heated, the second part is more likely to be deformed following the melting of the specific organic compound than the first part. For this reason, it is considered that bubbles are not generated in the second portion, or the ratio of bubbles in the second portion is lower than that of the first portion.

  In addition, in this embodiment, even if the heating temperature at the time of heating a coating film is lower than melting | fusing point of a specific organic compound, if it is more than the temperature which subtracted 30 degreeC from melting | fusing point of a specific organic compound, 1st part Bubbles are generated inside. The reason for this is not clearly understood, but one reason is that when a specific organic compound is mixed with another compound in the coating film, the melting point (freezing point) of the specific organic compound decreases. It is guessed.

It is preferable that the heating temperature of the coating film after exposure / development further satisfies the relationship of T _m + 100 ≧ T _h ≧ T _m −30. In this case, deterioration due to heat of components in the film-forming composition is suppressed.

  In this embodiment, the temperature of the coating film is maintained at a temperature lower than the melting point of the specific organic compound from the time when the coating film made of the film forming composition is formed until the time when the exposure of the coating film is completed. It is preferable. In this case, the ratio of bubbles in the first region is higher. For this reason, the difference in appearance color between the first region and the second region becomes more prominent. This is because if the specific organic compound melts in the first portion before the photopolymerizable compound in the first portion is polymerized, the specific organic compound is stabilized in the first portion, and thus the coating film Even if the first part is heated after the exposure, it is assumed that the first part is not easily deformed. More preferably, the temperature of the coating film is less than the temperature obtained by subtracting 30 ° C. from the melting point of the specific organic compound between the time when the composition for forming a film is placed on the wiring board and the time when the exposure of the coating film is completed. Keep at low temperature.

  The film forming composition in this embodiment will be described in more detail.

  The specific organic compound contained in the film-forming composition preferably has a clear melting point and becomes a low-viscosity liquid above this melting point.

  It is preferable that melting | fusing point of a specific organic compound exists in the range of 100-230 degreeC. In this case, when the film-forming composition is sufficiently exposed and then heated, bubbles are particularly likely to be generated in the cured product of the film-forming composition, and with respect to the entire cured product of the film-forming composition. The ratio of bubbles tends to be high.

  The specific organic compound can contain, for example, one or more compounds selected from the group consisting of a crystalline epoxy compound and a dicarboxylic acid.

  Moreover, the composition for film formation can also contain the compound contained in a specific organic compound while being contained in a photoinitiator.

  The crystalline epoxy compound can contain one or more compounds selected from the group consisting of monomers, prepolymers and polymers having an epoxy group and crystallinity. Such compounds are commercially available and are readily available. For example, the crystalline epoxy compound is 1,3,5-tris (2,3-epoxypropyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione (high melting type) Product name YDC-1312 (hydroquinone type crystalline epoxy resin) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Product name YSLV-120TE (thioether type crystalline epoxy resin) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Product name GTR manufactured by Nippon Kayaku Co., Ltd. -1800 (tetrakisphenolethane type crystalline epoxy resin), bisphenolfluorene type crystalline epoxy resin, product name YX-4000 (biphenyl type crystalline epoxy resin) manufactured by Mitsubishi Chemical Corporation, and 1,3,5-tris (2 , 3-epoxypropyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione (low It can contain least one compound selected from the group consisting of a point type).

  The dicarboxylic acid is, for example, one or more selected from the group consisting of malonic acid, succinic acid, adipic acid, oxalic acid, pimelic acid, suberic acid, sebacic acid, phthalic acid, and 4-cyclohexene-1,2-dicarboxylic acid Compounds can be included.

  Moreover, the compound contained in the photopolymerization initiator and also in the specific organic compound is, for example, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2-benzyl-2-dimethylamino-1- (4- Morpholinophenyl) -butanone-1 and ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (0-acetyloxime). .

  The film forming composition may contain an epoxy compound. The epoxy compound may contain a crystalline epoxy compound contained in the specific organic compound.

  When the film forming composition contains an epoxy compound, the film forming composition may contain an amorphous epoxy compound. The epoxy compound may contain both a crystalline epoxy compound and an amorphous epoxy compound.

  Non-crystalline epoxy compounds include, for example, non-crystalline cresol novolac type epoxy resin (specifically, product name EPICLON N-695 manufactured by DIC Corporation), non-crystalline phenol novolac type epoxy resin (specific example, manufactured by DIC Corporation). Product name EPICLON N-775), amorphous bisphenol A novolak type epoxy resin (specifically, product name EPICLON N-865 manufactured by DIC Corporation), amorphous bisphenol A type epoxy resin (specifically Mitsubishi Chemical Corporation) Company name jER1001), non-crystalline bisphenol F type epoxy resin (specifically, product name jER4004P manufactured by Mitsubishi Chemical Corporation), non-crystalline bisphenol S type epoxy resin (specific example, product name EPICLON manufactured by DIC Corporation) EXA-151 ), Non-crystalline bisphenol AD type epoxy resin, non-crystalline hydrogenated bisphenol A type epoxy resin, non-crystalline biphenyl novolac type epoxy resin, and non-crystalline special bifunctional type epoxy resin (as specific examples, Product numbers YL7175-500 and YL7175-1000 manufactured by Mitsubishi Chemical Corporation; product names EPICLON TSR-960, EPICLON TER-601, EPICLON TSR-250-80BX, EPICLON 1650-75MPX, EPICLON EXA-4850, EPICLON manufactured by DIC Corporation EXA-4816, EPICLON EXA-4822, and EPICLON EXA-9726; product name YSLV-120T manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., and other amorphous bisphenol-based epoxy It can contain one or more compounds selected from the group consisting of a resin.

  When the composition for film formation contains an epoxy compound, it is preferable that the composition for film formation contains the hardening | curing agent for hardening an epoxy compound. Examples of the curing agent include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2 Imidazole derivatives such as -cyanoethyl) -2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzylamine, Amine compounds such as 4-methyl-N, N-dimethylbenzylamine; hydrazine compounds such as adipic hydrazide and sebacic acid hydrazide; phosphorus compounds such as triphenylphosphine; acid anhydrides; phenols; mercaptans; Lewis acid amine complexes; Oni It can contain one or more compounds selected from the group consisting of unsalted. Examples of commercially available products of these compounds include 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (both trade names of imidazole compounds) manufactured by Shikoku Kasei Co., Ltd., U-CAT3503N, U manufactured by San Apro Co., Ltd. -CAT3502T (all are trade names of blocked isocyanate compounds of dimethylamine), DBU, DBN, U-CATSA102, U-CAT5002 (all are bicyclic amidine compounds and salts thereof). In addition, the curing agent is guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-4,6-diamino-S, which also functions as an adhesion promoter. -Contains S-triazine derivatives such as triazine, 2-vinyl-4,6-diamino-S-triazine / isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine / isocyanuric acid adduct You can also

  The resin having a carboxyl group imparts developability with an alkaline solution to a coating film formed from the film-forming composition.

  The resin having a carboxyl group can contain a resin having a carboxyl group and no photopolymerization (hereinafter referred to as a carboxyl group-containing non-photosensitive resin).

  The carboxyl group-containing non-photosensitive resin is a polymer of an ethylenically unsaturated monomer including, for example, an ethylenically unsaturated compound having a carboxyl group. The ethylenically unsaturated monomer may further contain an ethylenically unsaturated compound having no carboxyl group.

  The ethylenically unsaturated compound having a carboxyl group can contain appropriate polymers and prepolymers. For example, an ethylenically unsaturated compound having a carboxyl group can contain a compound having only one ethylenically unsaturated group. More specifically, ethylenically unsaturated compounds having a carboxyl group are, for example, acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, crotonic acid, cinnamic acid, 2-acryloyloxyethyl succinate. Acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl phthalic acid, β-carboxyethyl acrylate, acryloyloxyethyl succinate, methacryloyloxyethyl succinate, 2-propenoic acid , 3- (2-Carboxyethoxy) -3-oxypropyl ester, 2-acryloyloxyethyl tetrahydrophthalic acid, 2-methacryloyloxyethyl tetrahydrophthalic acid, 2-acryloyloxyethylhexyl One or more compounds selected from the group consisting of sahydrophthalic acid and 2-methacryloyloxyethyl hexahydrophthalic acid can be contained. The ethylenically unsaturated compound having a carboxyl group can also contain a compound having a plurality of ethylenically unsaturated groups. More specifically, for example, ethylenically unsaturated compounds having a carboxyl group are pentaerythritol triacrylate, pentaerythritol trimethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol. A compound obtained by reacting a dibasic acid anhydride with a polyfunctional (meth) acrylate having a hydroxyl group selected from the group consisting of pentamethacrylate can be contained. These compounds are used individually by 1 type, or multiple types are used together.

  The ethylenically unsaturated compound which does not have a carboxyl group should just be a compound copolymerizable with the ethylenically unsaturated compound which has a carboxyl group. The ethylenically unsaturated compound having no carboxyl group can contain both a compound having an aromatic ring and a compound having no aromatic ring.

  Examples of the compound having an aromatic ring include 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, 2- (meth) acryloyloxypropyl phthalate, and benzyl (meth). Acrylate, neopentyl glycol benzoate (meth) acrylate, paracumylphenoxyethylene glycol (meth) acrylate, EO-modified cresol (meth) acrylate, ethoxylated phenyl (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate (n = 2 to 2) 17), ECH-modified phenoxy (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxyhexaethylene glycol (meth) Acrylate, phenoxytetraethylene glycol (meth) acrylate, tribromophenyl (meth) acrylate, EO modified tribromophenyl (meth) acrylate, EO modified bisphenol A di (meth) acrylate, PO modified bisphenol A di (meth) acrylate, modified Bisphenol A di (meth) acrylate, EO modified bisphenol F di (meth) acrylate, ECH modified phthalic acid di (meth) acrylate, trimethylolpropane benzoate (meth) acrylate, EO modified phthalic acid (meth) acrylate, EO, PO modified One or more compounds selected from the group consisting of phthalic acid (meth) acrylate, vinyl carbazole, styrene, vinyl naphthalene, and vinyl biphenyl can be contained.

  The compound having no aromatic ring is, for example, a linear or branched aliphatic or alicyclic (however, the ring may partially have an unsaturated bond) (meth) acrylic acid ester, hydroxyalkyl One or more compounds selected from the group consisting of (meth) acrylates, alkoxyalkyl (meth) acrylates, etc .; and N-substituted maleimides such as N-cyclohexylmaleimide can be contained. Compounds that do not have an aromatic ring include ethylene glycol in one molecule such as polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate. You may contain the compound which has 2 or more of unsaturated unsaturated groups. These compounds are used individually by 1 type, or multiple types are used together. These compounds are preferable in that the hardness and oiliness of the solder resist layer can be easily adjusted.

  The kind, ratio, and the like of the compound used for obtaining the carboxyl group-containing non-photosensitive resin are appropriately selected so that the acid value of the carboxyl group-containing non-photosensitive resin becomes an appropriate value. The acid value of the carboxyl group-containing non-photosensitive resin is preferably in the range of 20 to 180 mgKOH / g, more preferably in the range of 35 to 165 mgKOH / g.

  The resin having a carboxyl group can also contain a resin having a carboxyl group and an ethylenically unsaturated group (hereinafter referred to as a carboxyl group-containing unsaturated resin). In addition, since carboxyl group-containing unsaturated resin has photopolymerizability, it is also contained in a photopolymerizable compound. That is, the carboxyl group-containing unsaturated resin serves as both a component contained in the resin having a carboxyl group and a component contained in the photopolymerizable compound.

  The carboxyl group-containing unsaturated resin includes, for example, an ethylenically unsaturated compound (a2) having a carboxyl group in at least one of the epoxy groups in the epoxy compound (a1) having two or more epoxy groups in one molecule. A resin having a structure to which a compound (a3) selected from the group consisting of at least one selected from polyvalent carboxylic acids and anhydrides is further added (hereinafter referred to as first resin (a)), Can be contained.

  The epoxy compound (a1) is, for example, a cresol novolak type epoxy resin, a phenol novolak type epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol A-novolak type epoxy resin, a naphthalene type epoxy resin, a biphenyl type epoxy resin, It may contain at least one compound selected from the group consisting of a polymer of an ethylenically unsaturated compound including a biphenyl aralkyl type epoxy resin, triglycidyl isocyanurate, an alicyclic epoxy resin, and a compound having an epoxy group.

  The epoxy compound (a1) may contain a polymer of an ethylenically unsaturated compound (p) including the compound (p1) having an epoxy group.

  The ethylenically unsaturated compound (p) used for the synthesis of this polymer may contain only the compound (p1) having an epoxy group, or the compound (p1) having an epoxy group and a compound not having an epoxy group (P2) may be contained.

  The compound (p1) having an epoxy group can contain a compound selected from appropriate polymers and prepolymers. Specifically, the compound (p1) having an epoxy group is an epoxy cyclohexyl derivative of acrylic acid, an epoxy cyclohexyl derivative of methacrylic acid, an alicyclic epoxy derivative of acrylate, an alicyclic epoxy derivative of methacrylate, or β-methylglycidyl acrylate. And one or more compounds selected from the group consisting of β-methylglycidyl methacrylate. In particular, it is preferable that the compound (p1) having an epoxy group contains glycidyl (meth) acrylate which is widely used and easily available.

  The compound (p2) not having an epoxy group may be a compound copolymerizable with the compound (p1) having an epoxy group. Examples of the compound (p2) having no epoxy group include 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, 2- (meth) acryloyloxypropyl phthalate, Benzyl (meth) acrylate, neopentyl glycol benzoate (meth) acrylate, paracumylphenoxyethylene glycol (meth) acrylate, EO-modified cresol (meth) acrylate, ethoxylated phenyl (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate ( Degree of polymerization n = 2 to 17), ECH-modified phenoxy (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxyhexaeth Glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, tribromophenyl (meth) acrylate, EO-modified tribromophenyl (meth) acrylate, EO-modified bisphenol A di (meth) acrylate, PO-modified bisphenol A di ( (Meth) acrylate, modified bisphenol A di (meth) acrylate, EO modified bisphenol F di (meth) acrylate, ECH modified phthalic acid di (meth) acrylate, trimethylolpropane benzoate (meth) acrylate, EO modified phthalic acid (meth) acrylate , EO, PO modified phthalic acid (meth) acrylate, vinyl carbazole, styrene, N-phenylmaleimide, N-benzylmaleimide, 3-maleimidobenzoic acid N-succinimid , (Meth) acrylic acid ester, hydroxyalkyl (meth) acrylate, alkoxyalkyl (which may have a linear or branched aliphatic or alicyclic group (but may partially have an unsaturated bond in the ring)) One or more compounds selected from the group consisting of (meth) acrylates and N-substituted maleimides (for example, N-cyclohexylmaleimide) can be contained.

  The compound having no epoxy group (p2) may further contain a compound having two or more ethylenically unsaturated groups in one molecule. This compound is used, and the hardness and oiliness of the solder resist layer are easily adjusted by adjusting the amount of the compound. Examples of the compound having two or more ethylenically unsaturated groups in one molecule include polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth). One or more compounds selected from the group consisting of acrylates can be contained.

  A polymer is obtained by polymerizing the ethylenically unsaturated compound (p) by a known polymerization method such as a solution polymerization method or an emulsion polymerization method. Specific examples of the solution polymerization method include a method of heating and stirring the ethylenically unsaturated compound (p) in a suitable organic solvent in the presence of a polymerization initiator in a nitrogen atmosphere and an azeotropic polymerization method.

  Examples of the organic solvent used for the polymerization of the ethylenically unsaturated compound (p) include ketones such as methyl ethyl ketone and cyclohexanone, and aromatic hydrocarbons such as toluene and xylene, and ethyl acetate, butyl acetate, and cellosolve acetate. One or more compounds selected from the group consisting of acetate esters such as butyl cellosolve acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, and dialkyl glycol ethers can be contained.

  The polymerization initiator used for the polymerization of the ethylenically unsaturated compound (p) is, for example, hydroperoxides such as diisopropylbenzene hydroperoxide, dicumyl peroxide, 2,5-dimethyl-2,5-di Dialkyl peroxides such as-(t-butylperoxy) -hexane, diacyl peroxides such as isobutyryl peroxide, ketone peroxides such as methyl ethyl ketone peroxide, alkyl peroxides such as t-butyl peroxybivalate , Peroxydicarbonates such as diisopropyl peroxydicarbonate, azo compounds such as azobisisobutyronitrile, and one or more compounds selected from the group consisting of redox initiators.

  The ethylenically unsaturated compound (a2) can contain a compound selected from the group consisting of appropriate polymers and prepolymers. The ethylenically unsaturated compound (a2) can contain a compound having only one ethylenically unsaturated group. Examples of the compound having only one ethylenically unsaturated group include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2 -Methacryloyloxyethylphthalic acid, β-carboxyethyl acrylate, acryloyloxyethyl succinate, methacryloyloxyethyl succinate, 2-propenoic acid, 3- (2-carboxyethoxy) -3-oxypropyl ester, 2-acryloyl Consists of oxyethyl tetrahydrophthalic acid, 2-methacryloyloxyethyl tetrahydrophthalic acid, 2-acryloyloxyethyl hexahydrophthalic acid, and 2-methacryloyloxyethyl hexahydrophthalic acid It can contain one or more compounds selected from. The ethylenically unsaturated compound (a2) can further contain a compound having a plurality of ethylenically unsaturated groups. Compounds having a plurality of ethylenically unsaturated groups are, for example, hydroxyl groups such as pentaerythritol triacrylate, pentaerythritol trimethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, etc. One or more compounds selected from the group consisting of compounds obtained by reacting dibasic acid anhydrides with polyfunctional acrylates and polyfunctional methacrylates can be contained.

  In particular, the ethylenically unsaturated compound (a2) preferably contains at least one of acrylic acid and methacrylic acid. In this case, since the ethylenically unsaturated group derived from acrylic acid and methacrylic acid is particularly excellent in photoreactivity, the photoreactivity of the first resin (a) is increased.

  The amount of the ethylenically unsaturated compound (a2) used is such that the carboxyl group of the ethylenically unsaturated compound (a2) is in the range of 0.4 to 1.2 mol with respect to 1 mol of the epoxy group of the epoxy compound (a1). It is preferable that the amount is such that the carboxyl group is in the range of 0.5 to 1.1 mol.

  The compound (a3) selected from the group consisting of polyvalent carboxylic acids and anhydrides thereof is, for example, phthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, methylnadic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, succinic acid. Dicarboxylic acids such as acid, methylsuccinic acid, maleic acid, citraconic acid, glutaric acid, itaconic acid; cyclohexane-1,2,4-tricarboxylic acid, trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid, methylcyclohexenetetracarboxylic acid One or more compounds selected from the group consisting of polybasic carboxylic acids such as tribasic acids and the like; and anhydrides of these polyvalent carboxylic acids.

  The compound (a3) is used mainly for the purpose of imparting re-dispersion and re-solubility with a dilute aqueous alkali solution to the film-forming composition by giving an acid value to the first resin (a). The amount of the compound (a3) used is adjusted so that the acid value of the first resin (a) is preferably 30 mgKOH / g or more, particularly preferably 60 mgKOH / g or more. The amount of the compound (a3) used is adjusted so that the acid value of the first resin (a) is preferably 160 mgKOH / g or less, particularly preferably 130 mgKOH / g or less.

  When the first resin (a) is synthesized, an addition reaction between the epoxy compound (a1) and the ethylenically unsaturated compound (a2), and a product (addition reaction product) and a compound (a3) obtained by the addition reaction. In the case of proceeding the addition reaction with (), a known method may be employed. For example, in the addition reaction between the epoxy compound (a1) and the ethylenically unsaturated compound (a2), the ethylenically unsaturated compound (a2) is added to the solvent solution of the epoxy compound (a1), and thermal polymerization is prohibited as necessary. A reactive solution is obtained by adding an agent and a catalyst and stirring and mixing. An addition reaction product is obtained by reacting this reactive solution at a reaction temperature of preferably 60 to 150 ° C., particularly preferably 80 to 120 ° C., by a conventional method. Examples of the thermal polymerization inhibitor include hydroquinone or hydroquinone monomethyl ether. Examples of the catalyst include tertiary amines such as benzyldimethylamine and triethylamine, quaternary ammonium salts such as trimethylbenzylammonium chloride and methyltriethylammonium chloride, triphenylphosphine, and triphenylstibine.

  In proceeding the addition reaction between the addition reaction product and the compound (a3), the compound (a3) is added to the solvent solution of the addition reaction product, and a thermal polymerization inhibitor and a catalyst are further added as necessary, followed by stirring and mixing. By doing so, a reactive solution is obtained. The first resin (a) is obtained by reacting this reactive solution by a conventional method. The reaction conditions may be the same as in the addition reaction of the epoxy compound (a1) and the ethylenically unsaturated compound (a2). As the thermal polymerization inhibitor and the catalyst, the compound used in the addition reaction between the epoxy compound (a1) and the ethylenically unsaturated compound (a2) having a carboxyl group can be used as it is.

  A carboxyl group-containing unsaturated resin is obtained by reacting an ethylenically unsaturated compound having an epoxy group with a part of a carboxyl group in a polymer of ethylenically unsaturated monomers including an ethylenically unsaturated compound having a carboxyl group. The resulting resin (referred to as second resin (b)) may be contained. The ethylenically unsaturated monomer may contain an ethylenically unsaturated compound having no carboxyl group, if necessary.

  The ethylenically unsaturated compound having a carboxyl group for obtaining the second resin (b) can contain an appropriate polymer and prepolymer. For example, an ethylenically unsaturated compound having a carboxyl group can contain a compound having only one ethylenically unsaturated group. More specifically, ethylenically unsaturated compounds having a carboxyl group are, for example, acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, crotonic acid, cinnamic acid, 2-acryloyloxyethyl succinate. Acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl phthalic acid, β-carboxyethyl acrylate, acryloyloxyethyl succinate, methacryloyloxyethyl succinate, 2-propenoic acid , 3- (2-Carboxyethoxy) -3-oxypropyl ester, 2-acryloyloxyethyl tetrahydrophthalic acid, 2-methacryloyloxyethyl tetrahydrophthalic acid, 2-acryloyloxyethylhexyl One or more compounds selected from the group consisting of sahydrophthalic acid and 2-methacryloyloxyethyl hexahydrophthalic acid can be contained. The ethylenically unsaturated compound having a carboxyl group can also contain a compound having a plurality of ethylenically unsaturated groups. More specifically, for example, ethylenically unsaturated compounds having a carboxyl group are pentaerythritol triacrylate, pentaerythritol trimethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol. A compound obtained by reacting a dibasic acid anhydride with a polyfunctional (meth) acrylate having a hydroxyl group selected from the group consisting of pentamethacrylate can be contained. These compounds are used individually by 1 type, or multiple types are used together.

  The ethylenically unsaturated compound having no carboxyl group for obtaining the second resin (b) may be any compound that can be copolymerized with the ethylenically unsaturated compound having a carboxyl group. The ethylenically unsaturated compound having no carboxyl group can contain both a compound having an aromatic ring and a compound having no aromatic ring.

  Examples of the compound having an aromatic ring include 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, 2- (meth) acryloyloxypropyl phthalate, and benzyl (meth). Acrylate, neopentyl glycol benzoate (meth) acrylate, paracumylphenoxyethylene glycol (meth) acrylate, EO-modified cresol (meth) acrylate, ethoxylated phenyl (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate (n = 2 to 2) 17), ECH-modified phenoxy (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxyhexaethylene glycol (meth) Acrylate, phenoxytetraethylene glycol (meth) acrylate, tribromophenyl (meth) acrylate, EO modified tribromophenyl (meth) acrylate, EO modified bisphenol A di (meth) acrylate, PO modified bisphenol A di (meth) acrylate, modified Bisphenol A di (meth) acrylate, EO modified bisphenol F di (meth) acrylate, ECH modified phthalic acid di (meth) acrylate, trimethylolpropane benzoate (meth) acrylate, EO modified phthalic acid (meth) acrylate, EO, PO modified One or more compounds selected from the group consisting of phthalic acid (meth) acrylate, vinyl carbazole, styrene, vinyl naphthalene, and vinyl biphenyl can be contained.

  The compound having no aromatic ring is, for example, a linear or branched aliphatic or alicyclic (however, the ring may partially have an unsaturated bond) (meth) acrylic acid ester, hydroxyalkyl One or more compounds selected from the group consisting of (meth) acrylates, alkoxyalkyl (meth) acrylates, etc .; and N-substituted maleimides such as N-cyclohexylmaleimide can be contained. Compounds that do not have an aromatic ring include ethylene glycol in one molecule such as polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate. You may contain the compound which has 2 or more of unsaturated unsaturated groups. These compounds are used individually by 1 type, or multiple types are used together. These compounds are preferable in that the hardness and oiliness of the solder resist layer can be easily adjusted.

  As the ethylenically unsaturated compound having an epoxy group for obtaining the second resin (b), an appropriate polymer or prepolymer may be mentioned. Specific examples of the ethylenically unsaturated compound having an epoxy group include epoxycyclohexyl derivatives of acrylic acid or methacrylic acid; alicyclic epoxy derivatives of acrylate or methacrylate; β-methylglycidyl acrylate, β-methylglycidyl methacrylate, and the like. . These compounds are used individually by 1 type, or multiple types are used together. In particular, it is preferable to use glycidyl (meth) acrylate which is widely used and easily available.

  The weight average molecular weight of the entire carboxyl group-containing unsaturated resin is preferably in the range of 800 to 100,000. Within this range, particularly excellent photosensitivity and resolution are imparted to the film-forming composition.

  The acid value of the entire carboxyl group-containing unsaturated resin is preferably 30 mgKOH / g or more, and in this case, good developability is imparted to the film-forming composition. The acid value is more preferably 60 mgKOH / g or more. The acid value of the entire carboxyl group-containing unsaturated resin is preferably 160 mgKOH / g or less. In this case, the residual amount of carboxyl groups in the film formed from the film-forming composition is reduced, and the film is good. Excellent electrical characteristics, electric corrosion resistance, water resistance and the like are maintained. The acid value is more preferably 130 mgKOH / g or less.

  The photopolymerizable compound imparts photocurability to the coating film formed from the film forming composition. The photopolymerizable compound may contain, for example, one or more compounds selected from the group consisting of a monomer having an ethylenically unsaturated group, a prepolymer having an ethylenically unsaturated group, and a polymer having an ethylenically unsaturated group. it can.

  As described above, the photopolymerizable compound can contain a carboxyl group-containing unsaturated resin.

  The photopolymerizable compound may contain a monomer having an ethylenically unsaturated group. Monomers having an ethylenically unsaturated group include monofunctional (meth) acrylates such as 2-hydroxyethyl (meth) acrylate; and diethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri ( Many products such as (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ε-caprolactone modified pentaerythritol hexaacrylate One or more compounds selected from the group consisting of functional (meth) acrylates can be contained.

  It is also preferred that the monomer having an ethylenically unsaturated group contains a phosphorus-containing compound (phosphorus-containing photopolymerizable compound). In this case, the flame retardancy of the cured product of the film forming composition is improved. Phosphorus-containing photopolymerizable compounds include, for example, 2-methacryloyloxyethyl acid phosphate (specific examples: product number light ester P-1M and light ester P-2M manufactured by Kyoeisha Chemical Co., Ltd.), 2-acryloyloxyethyl acid phosphate (As a specific example, product number light acrylate P-1A manufactured by Kyoeisha Chemical Co., Ltd.), diphenyl-2-methacryloyloxyethyl phosphate (as a specific example, product number MR-260 manufactured by Daihachi Kogyo Co., Ltd.), and Showa Polymer Co., Ltd. HFA series (part number HFA-6003, which is an addition reaction product of dipentaerystol hexaacrylate and HCA as a specific example, and product number HFA-6007, an addition reaction product of caprolactone-modified dipentaerystol hexaacrylate and HCA HFA-3 03, and may contain one or more compounds selected from the group consisting of HFA-6127, etc.).

  A photoinitiator can contain the photoinitiator for desired energy ray exposures, such as an ultraviolet-ray, visible light, infrared rays, near infrared rays, an electron beam. In addition, as above-mentioned, the composition for film formation may contain the compound contained in a specific organic compound while being contained in a photoinitiator.

  Examples of the photopolymerization initiator include benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether and alkyl ethers thereof; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2- Acetophenones such as phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone; anthraquinones such as 2-methylanthraquinone and 2-amylanthraquinone; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2 -Thioxanthones such as chlorothioxanthone, 2,4-diisopropylthioxanthone, 1-chloro-4-propoxythioxanthone; acetophenone dimethyl ketal, benzyl Ketals such as methyl ketal; benzophenone, 3,3-dimethyl-4-methoxybenzophenone, 3,3 ′, 4,4′-tetra (t-butylperoxylcarbonyl) benzophenone, 4-benzoyl-4′-methyldiphenyl Benzophenones or xanthones such as sulfide; 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) ) -Butanone-1,4,4'-bis-diethylaminobenzophenone and the like containing a nitrogen atom; and one or more compounds selected from the group consisting of 2,4,6-trimethylbenzoyldiphenylphosphine oxide Can do.

  The film forming composition may contain a colorant. When the film-forming composition contains a colorant, as described above, the appearance color of the first region in the film formed from the film-forming composition is mainly the color of the colorant, whereas the second region The appearance color is a color obtained by mixing the color of the colorant and the color of the surface of the wiring board. Thereby, the area | region from which a color differs mutually is formed in a film.

  In addition, a coloring agent is a substance which colors the film formed from the composition for film formation. The colorant can include both pigments and dyes. However, a substance that is colored but becomes colorless by being heated in the process of producing a film from the film-forming composition is not included in the colorant because it does not color the film.

  When the film forming composition contains a colorant, the colorant may contain any of a pigment, a dye, and a pigment.

  For example, the colorant may contain materials that are numbered with a color index (CI; issued by The Society of Dyers and Colorists).

  For example, the colorant is a kind selected from the group consisting of a red colorant, a blue colorant, a green colorant, a yellow colorant, a purple colorant, an orange colorant, a brown colorant, and a colorant of a color other than those described above. The above materials can be contained.

  Specific examples of red colorants include monoazo red colorants, disazo red colorants, azo lake red colorants, benzimidazolone red colorants, perylene red colorants, diketopyrrolopyrrole red colorants, condensation Examples include azo red colorants, anthraquinone red colorants, and quinacridone. As a more specific example of a red colorant, Pigment Red 1, 2, 3, 4, 5, 6, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23,31, 32, 112 , 114, 146, 147, 151, 170, 184, 187, 188, 193, 210, 245, 253, 258,266, 267, 268, and 269; Pigment Red 37, 38, and 41; Pigment Red 48: 1, 48: 2, 48: 3, 48: 4, 49: 1, 49: 2, 50: 1, 52: 1, 52: 2, 53: 1, 53: 2, 57: 1, 58: 4, 63: 1, 63: 2, 64: 1, and 68; Pigment Red 171; Pigment Red 175; Pigment Red 176; Pigment Red 185; Pigment Red 208; Pigment Red 123; Pigment Red 149; Pigment Red 166; Pigment Red 194; Pigment Red 254; Pigment Red 254; Pigment Red 264; Pigment Red 272; Pigment Red 220; Pigment Red 144; Pigment Red 166; Pigment Red 166; Pigment Red 214; Pigment Red 221; Pigment Red 177; Pigment Red 216; Pigment Red 216; Pigment Red 202; Pigment Red 206; Pigment Red 207;

  Specific examples of the blue colorant include phthalocyanine blue colorants, anthraquinone blue colorants, and metal-substituted or unsubstituted phthalocyanine compounds. More specific examples of blue colorants include: Pigment Blue 15; Pigment Blue 15: 1; Pigment Blue 15: 2; Pigment Blue 15: 3; Pigment Blue 15: 4; Pigment Blue 15: 6; Pigment Blue 16; Blue 60 is mentioned.

  Specific examples of the green colorant include phthalocyanine green colorants, anthraquinone green colorants, perylene green colorants, and metal-substituted or unsubstituted phthalocyanine compounds. More specific examples of green colorants include Pigment Green 7; and Pigment Green 36.

  Specific examples of yellow colorants include monoazo yellow colorants, disazo yellow colorants, condensed azo yellow colorants, benzimidazolone yellow colorants, isoindolinone yellow colorants, and anthraquinone yellow colorants. Can be mentioned. As more specific examples of yellow colorants, Pigment Yellow 24; Pigment Yellow 108; Pigment Yellow 193; Pigment Yellow 147; Pigment Yellow 199; Pigment Yellow 202; Pigment Yellow 110; Pigment Yellow 109; Pigment Yellow 185; Pigment Yellow 93; Pigment Yellow 94; Pigment Yellow 95; Pigment Yellow 128; Pigment Yellow 166; Pigment Yellow 156; Pigment Yellow 154; Yellow 175; Pigment Yellow 181; Pigment Yellow 1, 2, 3, 4, 5, 6, 9, 10, 12, 61, 62, 62: 1, 65, 73,74, 75, 97, 100, 104, 105 , 111, 116, 167, 168, 169, 182, and 183; and Pigment Yellow 12, 13, 14, 16, 17,55, 63, 81, 83, 87, 126, 127, 152, 170, 172, 174 , 176, 188, and 198.

  Specific examples of purple colorant, orange colorant, brown colorant, etc. include Pigment Violet 19, 23, 29, 32, 36, 38, and 42; CI Pigment Orange 1; CI Pigment Orange 5; CI Pigment Orange 13; CI Pigment Orange 14, CI Pigment Orange 16, CI Pigment Orange 17, CI Pigment Orange 24, CI Pigment Orange 34, CI Pigment Orange 36, CI Pigment Orange 38, CI Pigment Orange 40, CI Pigment Orange 43, CI Pigment Orange 46; CI Pigment Orange 49; CI Pigment Orange 51; CI Pigment Orange 61; CI Pigment Orange 63; CI Pigment Orange 64; CI Pigment Orange 71; CI Pigment Orange 73; CI Pigment Brown 23; CI and Pigment And Brown 25.

  Specific examples of the black colorant include carbon black and naphthalene black.

  A specific example of the white colorant is titanium oxide.

  The composition for forming a film is a known benzoic acid type or a known tertiary photopolymerization accelerator such as p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid isoamyl ester, 2-dimethylaminoethylbenzoate, etc. An agent, a sensitizer and the like may be contained. The film-forming composition is a sensitizer for laser exposure, such as coumarin derivatives such as 7-diethylamino-4-methylcoumarin, 4,6-diethyl-7-ethylaminocoumarin, other carbocyanine dyes, and xanthene dyes. A system or the like may be contained.

  The composition for forming a film does not contain a colorant, or contains a colorant, but the ratio thereof may be a low value that does not cause coloration of the film. In this case, as described above, the appearance color of the first region in the film formed from the film-forming composition appears white, the second region is transparent, and the color of the surface of the wiring board that is the base is transparent. Looks. Therefore, regions having different colors can be formed on the film only by partially varying the exposure amount during exposure.

  When the film-forming composition does not contain a colorant, or contains a colorant, but the ratio is a low value that does not cause coloration of the film, the film-forming composition is colored, You may contain the substance which becomes colorless by heating in the process of manufacturing a film from the composition for film formation. This substance is not included in the colorant as described above. As such a substance, for example, a dye having a thermal decomposition temperature lower than the heating temperature at the time of heating the coating film after exposure and development (hereinafter referred to as a specific dye) can be mentioned. The thermal decomposition temperature of the specific dye depends on the heating temperature of the coating film, but is preferably in the range of 60 to 200 ° C. Specific examples of the specific dye include Solvent Red 135; Solvent Red 179; Solvent Red 149; Solvent Red 150; Solvent Red 52; Solvent Red 207; Solvent Blue 35; Solvent Blue 63; Solvent Blue 68; Solvent Blue 70; Solvent Blue 83; Solvent Blue 87; Solvent Blue 94; Solvent Blue 97; Solvent Blue 122; Solvent Blue 136; Solvent Blue 67; Solvent Green 3; Solvent Green 5; Solvent Green 20; Solvent Green 28; Solvent Yellow 163; Solvent Violet 13 and 36 are mentioned.

  The composition for forming a film may contain a filler. In this case, the curing shrinkage of the coating film formed from the film forming composition is reduced. The filler can contain, for example, one or more materials selected from the group consisting of silica, barium sulfate, carbon nanotubes, aluminum hydroxide, and magnesium hydroxide.

  The composition for forming a film may further contain an appropriate additive as necessary. For example, the composition for forming a film includes a copolymer such as silicone and acrylate; a leveling agent; an adhesion imparting agent such as a silane coupling agent; a thixotropic agent; a polymerization inhibitor; an antihalation agent; a flame retardant; One or more compounds selected from the group consisting of an inhibitor; a surfactant; and a polymer dispersant may be contained.

  The composition for forming a film may contain an organic solvent. The organic solvent is used for the purpose of liquefaction or varnishing of the film-forming composition, viscosity adjustment, application property adjustment, film formation property adjustment and the like.

  Organic solvents include, for example, linear, branched, secondary or polyhydric alcohols such as ethanol, propyl alcohol, isopropyl alcohol, hexanol and ethylene glycol; ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene and xylene Petroleum aromatic mixed solvents such as Swazol series (manufactured by Maruzen Petrochemical Co., Ltd.) and Solvesso series (manufactured by Exxon Chemical Co.); cellosolves such as cellosolve and butylcellosolve; Tolls; Propylene glycol alkyl ethers such as propylene glycol methyl ether; Polypropylene glycol alkyl ethers such as dipropylene glycol methyl ether; Acetic acid such as ethyl acetate, butyl acetate and cellosolve acetate It can contain, as well as one or more compounds selected from the group consisting of dialkyl glycol ethers; ester compounds.

  The ratio of the organic solvent in the film-forming composition is such that the organic solvent quickly volatilizes during the preliminary drying of the film formed from the film-forming composition, that is, the organic solvent does not remain in the dry film. It is preferable to adjust. In particular, the ratio of the organic solvent in the film forming composition is preferably in the range of 5 to 99.5% by mass. In this case, good coatability of the film forming composition can be obtained. In addition, since the suitable ratio of an organic solvent changes with application methods etc., it is preferable that a ratio is suitably adjusted according to the application method.

  The raw material of the film forming composition as described above is blended, and the film forming composition can be prepared by kneading by a known kneading method using, for example, a three-roll, ball mill, sand mill or the like.

  In consideration of storage stability and the like, the first agent may be prepared by mixing a part of the raw material of the film-forming composition, and the second agent may be prepared by mixing the rest of the raw material. For example, the first agent is prepared by previously mixing and dispersing a part of the photopolymerizable compound and the organic solvent and the epoxy compound among the raw materials, and the second agent by mixing and dispersing the rest of the raw materials. It may be prepared. In this case, the composition for film formation can be prepared by mixing the necessary amount of the first agent and the second agent in a timely manner.

  The ratio of the specific organic compound in the composition for forming a film is preferably in the range of 1.0 to 65% by mass, more preferably in the range of 1.2 to 60% by mass with respect to the solid content. If it is in the range of 1.4-55 mass%, it is still more preferable, and if it is in the range of 1.6-50 mass%, it is especially preferable.

  As described above, the photopolymerizable compound in the film-forming composition can contain at least one of a carboxyl group-containing unsaturated resin and a monomer having an ethylenically unsaturated group. The ratio of the photopolymerizable compound is preferably in the range of 10 to 90% by mass with respect to the solid content, and more preferably in the range of 15 to 85% by mass.

  When the photopolymerizable compound contains a monomer having an ethylenically unsaturated group, the proportion of the monomer having an ethylenically unsaturated group is preferably in the range of 1 to 45% by mass with respect to the solid content. More preferably within the range of 40% by mass.

  When the photopolymerizable compound contains a carboxyl group-containing unsaturated resin, the proportion of the carboxyl group-containing unsaturated resin is preferably within a range of 5 to 85% by mass with respect to the solid content, and is preferably 10 to 80% by mass. It is more preferable if it is within the range.

  As described above, the resin having a carboxyl group can contain at least one of a carboxyl group-containing non-photosensitive resin and a carboxyl group-containing unsaturated resin. The proportion of the resin having a carboxyl group is preferably in the range of 5 to 85% by mass, more preferably in the range of 10 to 80% by mass with respect to the solid content.

  When the resin having a carboxyl group contains a carboxyl group-containing non-photosensitive resin, the proportion of the carboxyl group-containing non-photosensitive resin is preferably within a range of 5 to 80% by mass with respect to the solid content, and is preferably 10 to 75. If it is in the range of mass%, it is still more preferable.

  Moreover, when the composition for film formation contains an epoxy compound, it is preferable that the ratio of an epoxy compound exists in the range of 1.5-65 mass% with respect to solid content, and is 3.0-60 mass%. It is more preferable if it is within the range.

  It is preferable that the ratio of a photoinitiator exists in the range of 0.1-30 mass% with respect to solid content.

  When the film-forming composition contains a colorant, the ratio of the colorant is preferably in the range of 0.05 to 15% by mass, and in the range of 0.1 to 10% by mass with respect to the solid content. If it is more preferable.

  Moreover, as above-mentioned, the composition for film formation does not contain a coloring agent, or a coloring agent is contained, but the ratio may be a low value which does not produce coloring in a coating film. In order to prevent the coating from being colored even if it contains a colorant, the ratio of the colorant is preferably 0.04% by mass or less based on the solid content.

  In addition, solid content is a total amount of all components except the component which volatilizes in the formation process of films, such as a solvent, in the composition for film formation.

  The film forming composition according to this embodiment is applied to form a film on a wiring board.

  Below, the method of forming a film on a wiring board using the composition for film formation by this embodiment is demonstrated with reference to FIGS.

  In this method, a composition (second film forming composition) having an alkali developability different from the film forming composition is used together with the film forming composition. The second film-forming composition is colored (for example, black). When the film forming composition contains a colorant, the second film forming composition preferably has a color different from that of the colorant in the film forming composition. Furthermore, the second film-forming composition has photosensitivity (photocurability).

  A wiring board 1 is prepared. The wiring board 1 is, for example, a printed wiring board.

  On this wiring board 1, the 2nd composition for film formation is apply | coated, and a coating film (2nd coating film 5) is formed. ) The coating method of the second film-forming composition is selected from the group consisting of known methods such as dipping, spraying, spin coating, roll coating, curtain coating, and screen printing.

  Subsequently, in order to volatilize the organic solvent in the second film-forming composition as necessary, preliminary drying is performed at a temperature in the range of 60 to 100 ° C., for example, so that the second coating film 5 is formed. dry.

  Then, the composition for film formation is apply | coated on the 2nd coating film 5, and the coating film 2 is formed as shown in FIG. The coating method for the film-forming composition is selected from the group consisting of known methods such as dipping, spraying, spin coating, roll coating, curtain coating, and screen printing.

  Subsequently, the coating film 2 is heated (preliminary drying) in order to volatilize the organic solvent in the film-forming composition as necessary. In this case, the heating temperature is preferably lower than the melting point of the specific organic compound in the film-forming composition, and more particularly than the temperature obtained by subtracting 30 ° C. from the melting point of the specific organic compound in the film-forming composition. A low temperature is preferred. This heating temperature is, for example, in the range of 60 to 100 ° C.

  In forming the coating film 2 on the wiring board 1, a coating film 2 is formed by applying a coating forming composition on an appropriate support in advance and then drying the coating film 2. The dry film may be transferred onto the wiring board 1 by applying pressure to the dry film and the wiring board 1 after being overlaid on the wiring board 1 (dry film method). In this case, preliminary drying may be omitted.

  Subsequently, as shown in FIG. 2, the coating film 2 and the second coating film 5 are exposed to light through a mask 4 to expose the coating film 2 and the second coating film 5.

  The light for exposure is selected so that the photopolymerization reaction of the photopolymerizable compound in the composition for film formation proceeds upon irradiation with this light. For example, ultraviolet light, visible light, or near infrared light is selected as light for exposure. When ultraviolet light is selected, the ultraviolet light source is selected from the group consisting of, for example, chemical lamps, low pressure mercury lamps, medium pressure mercury lamps, high pressure mercury lamps, ultra high pressure mercury lamps, xenon lamps and metal halide lamps.

  The mask 4 includes three types of portions having different degrees of light transmission. For example, the mask 4 includes a light transmissive portion (hereinafter referred to as a transmissive portion 41), a light transmissive portion lower than the transmissive portion 41 (hereinafter referred to as a low transmissive portion 42), and a light transmissive property. A portion (hereinafter referred to as a non-permeable portion 43).

  When the coating film 2 is exposed through the mask 4, the portion corresponding to the transmissive portion 41 in the coating film 2 (first portion 21) is irradiated with light, and the low-transmissive portion 42 in the coating film 2 is irradiated. The portion corresponding to (the second portion 22) is irradiated with light at an exposure amount lower than that of the first portion 21, and the portion corresponding to the non-transmissive portion 43 in the coating film 2 (third portion 23). Is not irradiated with light. The first portion 21 is a portion irradiated with light at the time of exposure, and the second portion 22 is a portion irradiated with light at an exposure amount lower than that of the first portion 21 at the time of exposure. It can also be said that the portion 23 is a portion that is not irradiated with light during exposure. The mask 4 is designed so that the first portion 21, the second portion 22, and the third portion 23 are located at predetermined positions in the coating film 2.

  When the coating film 2 is exposed in this manner, the photopolymerization reaction of the photopolymerizable compound proceeds in the first portion 21 of the coating film 2, and the second portion 22 has a lower degree than the first portion 21. The photopolymerization reaction of the photopolymerizable compound proceeds. On the other hand, in the third portion 23, the photopolymerization reaction of the photopolymerizable compound does not proceed.

  Note that the mask 4 as described above may not be used as long as the exposure amounts in the first portion 21, the second portion 22, and the third portion 23 can be controlled to desired values. For example, first, the coating film 2 is irradiated with light through a mask (first mask) that shields the third portion 23 and does not shield the first portion 21 and the second portion 22, and then continues to the second portion. A mask (second mask) that shields the second portion 22 and does not shield the first portion 21 is superimposed on one mask, and further light is irradiated through the first mask and the second mask. May be. Even in this case, the first portion 21 is irradiated with light, the second portion 22 is irradiated with light at a lower exposure amount than the first portion 21, and the third portion 23 is irradiated with light. Not irradiated.

  The ratio of the exposure amount of the second portion 22 to the exposure amount of the first portion 21 is, for example, in the range of 1 to 75%, and particularly preferably in the range of 1.2 to 60%.

Moreover, the exposure amount of the 1st part 21 is in the range of 100-5000 mJ / cm < ² >, for example, and the exposure amount of the 2nd part 22 is in the range of 20-500 mJ / cm < ² >, for example.

  The second coating film 5 is also exposed at the same time as the coating film 2, and the portions corresponding to the transmissive portion 41 and the low-transmissive portion 42 in the second coating film 5 are irradiated with light, and this portion is cured. . On the other hand, the portion corresponding to the non-permeable portion 43 in the second coating film 5 is not irradiated with light.

  After the exposure of the coating film 2 and the second coating film 5, the coating film 2 and the second coating film 5 are developed with an alkaline developer. Then, the third portion 23 of the coating film 2 is removed from the wiring board 1, and the portion corresponding to the non-permeable portion 43 in the second coating film 5 is also removed from the wiring board 1. The first portion 21 and the second portion 22 of the coating film 2 remain on the wiring board 1.

  Specific examples of the alkaline developer include sodium carbonate aqueous solution, potassium carbonate aqueous solution, ammonium carbonate aqueous solution, sodium hydrogen carbonate aqueous solution, potassium hydrogen carbonate aqueous solution, ammonium hydrogen carbonate aqueous solution, sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, ammonium hydroxide aqueous solution, Examples include tetramethylammonium hydroxide aqueous solution and lithium hydroxide aqueous solution. As the developer, organic amines such as monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, and triisopropanolamine can be used. The solvent in the alkaline developer may be water alone or a mixture of water and a hydrophilic organic solvent such as lower alcohols.

After the coating film is exposed, the coating film 2 (the first portion 21 and the second portion 22) on the wiring board 1 is heated. In this case, the heating temperature of the coating film 2 satisfies the relationship of T _h ≧ T _m −30, and preferably satisfies the relationship of T _m + 100 ≧ T _h ≧ T _m −30. In this formula, T _h (° C.) is the heating temperature of the coating film 2, and T _m (° C.) is the melting point of the specific organic compound. The heating temperature is, for example, in the range of 100 to 200 ° C. The heating time is in the range of 20 minutes to 5 hours.

  When the coating film 2 is heated in this way, bubbles are generated in the first portion 21. On the other hand, bubbles are not generated in the second portion 22 or bubbles are generated, but the ratio is lower than that of the first portion 21. Moreover, when the coating film 2 is heated in this way, when the composition for forming a film contains an epoxy compound, a thermosetting reaction of the epoxy compound proceeds.

  After the first portion 21 and the second portion 22 are heated, the entire first portion 21 and the second portion 22 may be irradiated with light. In this case, the photopolymerization reaction of the photopolymerizable compound remaining unreacted in the first portion 21 and the second portion 22 proceeds.

  As a result, as shown in FIG. 3, a coating (second coating 6) made of a cured product of the second coating 5 is formed on the wiring board 1, and the coating is formed on the second coating 6. A film (coating 3) made of the cured product 2 is formed. Thereby, the coated wiring board 1 is obtained. The coating 3 includes a first region 31 that is a cured product of the first portion 21 and a second region 32 that is a cured product of the second portion 22. The first region 31 contains bubbles. On the other hand, the second region 32 does not contain bubbles or contains bubbles at a lower density than the first region 31. For this reason, there is a difference in light transmittance between the first region 31 and the second region 32, and the second region 32 has higher light transmittance than the first region 31.

  For this reason, when the film forming composition contains a colorant, the appearance color of the first region 31 is mainly the color of the colorant, whereas the appearance color of the second region 32 is the colorant. And the color of the second coating 6 are mixed. For example, when the color of the colorant is green and the color of the second coating 6 is black, the appearance color of the first region 31 is green, and the color of the second region 32 is black or dark green. Become. In addition, when the composition for forming a film does not contain a colorant or contains a colorant but its proportion is small, the appearance color of the first region 31 appears white and the second region 32 is transparent. Then, the color of the second film 6 as the base can be seen through.

  The ratio of bubbles in the first region 31 is preferably in the range of 3 to 70%, and more preferably in the range of 5 to 60%. Moreover, it is preferable that the ratio of the value of the bubble ratio in the second region 32 to the value of the bubble ratio in the first region 31 is in the range of 0 to 5%.

The ratio of the bubbles is the area ratio of bubbles having a major axis of 0.5 μm or more on the surface appearing by polishing the surface of the coating 3 (that is, the cross section of the coating 3 along the surface of the coating 3). This area ratio is derived based on the area of bubbles having a major axis of 0.5 μm or more on the surface having a surface area of 20 μm ^{2 in} the coating film, for example.

  These ratios can be controlled by appropriately adjusting the exposure amount of the first portion 21 and the exposure amount of the second portion 22 during exposure.

  By forming the coating 3 on the coated wiring board 1 in this manner, the coating 3 is easily marked. For example, the first region 31 is formed into an appropriate figure, character, or the like, whereby the marking by the first region 31 is formed. Moreover, the marking by the 2nd area | region 32 may be formed by forming the 2nd area | region 32 in shapes, such as a suitable figure and a character. For this reason, marking can be performed simultaneously with the formation of the coating 3.

  In this method, the second coating 6 and the coating 3 are formed on the wiring board 1, but the coating 3 is formed directly on the wiring board 1 without forming the second coating 6. Also good. In this case, when the coating 3 is observed from the outside, when the coating forming composition contains a colorant, the appearance color of the first region 31 is mainly the color of the colorant, and the second region The appearance color of 32 is a color obtained by mixing the color of the colorant and the color of the surface of the wiring board 1. In addition, when the composition for forming a film does not contain a colorant or contains a colorant but its proportion is small, the appearance color of the first region 31 appears white and the second region 32 is transparent. Then, the color of the wiring board 1 which is the base can be seen through.

  The coating 3 on the coated wiring board 1 may be, for example, a solder resist. When the coating 3 is formed on the second coating 6 as in the present method, the coating 3 and the second coating 6 may constitute a multilayer solder resist.

  The thickness of the coating 3 is, for example, in the range of 3 to 60 μm. In this thickness range, the difference between the appearance color of the first region 31 and the appearance color of the second region 32 is clearly visible. In particular, even when the coating 3 is a thin film having a thickness of 3 to 25 μm, in this embodiment, the difference between the appearance color of the first region 31 and the appearance color of the second region 32 is clearly visible. Is possible. When the film 3 is in the range of 3 to 25 μm in thickness, the ratio of bubbles in the first region 31 is preferably in the range of 5 to 70%, and the value of the ratio of bubbles in the first region 31 is The ratio of the value of the ratio of bubbles in the second region 32 is preferably in the range of 0 to 5%.

  The carboxyl group-containing unsaturated resin solution A-1 used in the examples was prepared as follows.

  First, a cresol novolak type epoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., product number YDCN-700-5, epoxy equivalent 203) is placed in a four-necked flask equipped with a reflux condenser, a thermometer, an air blowing tube and a stirrer. A mixture was prepared by adding 203 parts by mass, 103 parts by mass of diethylene glycol monoethyl ether acetate, 0.2 parts by mass of methylhydroquinone, 72 parts by mass of acrylic acid, and 1.5 parts by mass of triphenylphosphine. This mixture was heated under the conditions of a heating temperature of 110 ° C. and a heating time of 10 hours, thereby allowing the addition reaction to proceed. Subsequently, 60.8 parts by mass of tetrahydrophthalic anhydride and 78.9 parts by mass of diethylene glycol monoethyl ether acetate were added to the mixture, and the mixture was further heated under the conditions of a heating temperature of 80 ° C. and a heating time of 3 hours. This obtained the 65 mass% concentration solution (carboxyl group containing unsaturated resin solution A-1) of carboxyl group containing unsaturated resin.

  Moreover, the carboxyl group-containing non-photosensitive resin solution A-2 used in the examples was prepared as follows.

  A four-necked flask equipped with a reflux condenser, a thermometer, a glass tube for nitrogen substitution, and a stirrer was mixed with 42 parts by weight of methacrylic acid, 43 parts by weight of methyl methacrylate, 35 parts by weight of styrene, 35 parts by weight of benzyl acrylate, and dipropylene glycol. 100 parts by mass of monomethyl ether, 0.5 parts by mass of lauryl mercaptan, and 4 parts by mass of azobisisobutyronitrile were added. The liquid in the four-necked flask was heated at 75 ° C. for 5 hours under a nitrogen stream to advance the polymerization reaction. Thereby, a 50% by mass solution of the copolymer (carboxyl group-containing non-photosensitive resin solution A-2) was obtained.

Details of the raw materials other than the carboxyl group-containing unsaturated resin solution A-1 and the carboxyl group-containing non-photosensitive resin A-2 used in the examples are as follows.
Photopolymerizable monomer A: dipentaerythritol hexaacrylate (DPHA).
Crystalline epoxy compound A: 1,3,5-tris (2,3-epoxypropyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione (high melting point type) Mp 158 ° C.
Crystalline epoxy compound B: Hydroquinone type crystalline epoxy resin. Product name YDC-1312 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Mp 145 ° C.
Crystalline epoxy compound C: Biphenyl type crystalline epoxy resin. Product name YX-4000 manufactured by Mitsubishi Chemical Corporation. Melting point 105 ° C.
Non-crystalline epoxy compound A: non-crystalline cresol novolac type epoxy resin. Product name EPICLON N-695 manufactured by DIC Corporation.
Dicarboxylic acid A: malonic acid, melting point 130 ° C.
Dicarboxylic acid B: 4-cyclohexene-1,2-dicarboxylic acid, manufactured by Shin Nippon Chemical Co., Ltd., product name Riccad TH-W, melting point 165 ° C.
Photopolymerization initiator A: Product name Irgacure 907 manufactured by BASF, melting point 72 ° C.
Photopolymerization initiator B: 2,4-diethylthioxanthen-9-one (DETX), melting point 68 ° C.
Photopolymerization initiator C: bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, product name Irgacure 819 manufactured by BASF, melting point 130 ° C.
Photopolymerization initiator D: 1-hydroxy-cyclohexyl-phenyl-ketone, product name Irgacure 184 manufactured by BASF, melting point 47 ° C.
Barium sulfate: Product name Variace B30 manufactured by Sakai Chemical Industry Co., Ltd.
・ Fine silica: Product name Leolosil MT-10 manufactured by Tokuyama Corporation.
Melamine resin: Product name Melamine HM manufactured by Nissan Chemical Industries, Ltd.
Colorant: Product name Lionol Green 6Y-501 manufactured by Toyo Ink Manufacturing Co., Ltd.
Antifoaming agent: Product name KS-66 manufactured by Shin-Etsu Chemical Co., Ltd.
Solvent: diethylene glycol monoethyl ether acetate.

[Examples 1-6, 9, 11-16, 19, 21, Reference Examples 7 , 8 , 10 , 17 , 18 , 20 , Comparative Examples 1-4]
The composition for film formation was prepared by mixing the components shown in Tables 1 to 3 with the compositions shown in Tables 1 to 3.

  Moreover, the printed wiring board whose surface color is black was prepared.

  A coating film was formed on the surface of the printed wiring board by applying the film-forming composition by a screen printing method. This coating film was heated at 80 ° C. for 30 minutes.

Subsequently, the coating film is passed through a mask having a light-transmissive part, a low-light part having a light transmittance lower than that of the light-transmissive part, and a non-light-transmissive part having no light permeability. The coating film was exposed by irradiating with ultraviolet rays. The exposure amount in the portion irradiated with the light transmitted through the transmissive portion in the coating film was 400 mJ / cm ² , and the exposure amount in the portion irradiated with the light transmitted through the low transmissive portion was 50 mJ / cm ² .

The exposed coating film was developed by spraying a 1% Na ₂ CO ₃ aqueous solution at a pressure of 0.2 MPa for 60 seconds.

  Subsequently, the coating film was heated at 150 ° C. for 1 hour.

Furthermore, in Examples 2 and 13, the entire coating film was exposed. This exposure amount is 1000 mJ / cm ² .

  The thickness of the film thus formed is as shown in the table.

  The appearance of this film was visually observed, and it was confirmed whether or not the region (third region) where light irradiation was blocked by the non-transmissive portion during exposure was removed by development. As a result, a case where no development residue was observed was evaluated as good and a case where a development residue was observed was evaluated as defective. The results are shown in the column of “Developability” in Tables 1 to 3.

  In addition, the appearance of the coating was visually observed, and the coating was exposed to the region exposed by the light transmitted through the transmissive part during exposure (first region) and the light transmitted through the low transmissive part during exposure. Appearance color with the region (second region) was confirmed.

  In addition, the appearance of the film was visually observed, and it was confirmed whether or not the first region and the second region were clearly distinguishable. As a result, “A” was clearly distinguishable. Was evaluated as “B”, unclear but distinguishable as “C”, and indistinguishable as “D”. The result is shown in the column “Visibility of marking”.

Also, the surface of the coating was polished, and the surface that appeared was observed, and based on the result, the ratio of bubbles in the first region and the ratio of bubbles in the second region were derived. In deriving the ratio of the bubbles, in each of the first region and the second region, the occupation ratio of the bubbles having a major axis of 0.5 μm or more in the area of 20 μm ² of the surface appearing by the polishing is calculated. The ratio of As a result, “A” indicates that the ratio of bubbles is 9% or more, “B” indicates that the ratio of bubbles is 6% or more and less than 9%, and “B” indicates that the ratio of bubbles is 3% or more and less than 6%. The case where the ratio of bubbles was less than 3% was evaluated as “D”.

  The results are shown in Tables 1 to 3 below.

[ Examples 22-27 , 30, 32-37 , 40 , 42 , Reference Examples 28 , 29 , 31 , 38 , 39 , 41 , Comparative Examples 5-8]
The composition for film formation was prepared by mixing the components shown in Tables 4-6 with the compositions shown in Tables 4-6.

  A printed wiring board was also prepared. On this printed wiring board, a black negative photo solder resist ink was applied and heated at 80 ° C. for 15 minutes. The thickness of the coating film of the photo solder resist ink after heating was 10 μm.

  On the coating film of this photo solder resist ink, the coating film forming composition was applied by a screen printing method to form a coating film. This coating film was heated at 80 ° C. for 30 minutes.

Subsequently, the coating film is passed through a mask having a light-transmissive part, a low-light part having a light transmittance lower than that of the light-transmissive part, and a non-light-transmissive part having no light permeability. The coating film was exposed by irradiating with ultraviolet rays. The exposure amount in the portion irradiated with the light transmitted through the transmissive portion in the coating film was 400 mJ / cm ² , and the exposure amount in the portion irradiated with the light transmitted through the low transmissive portion was 50 mJ / cm ² .

The exposed coating film was developed by spraying a 1% Na ₂ CO ₃ aqueous solution at a pressure of 0.2 MPa for 60 seconds.

  Subsequently, the coating film was heated at 150 ° C. for 1 hour.

Furthermore, in Examples 23 and 34, the entire coating film was exposed. This exposure amount is 1000 mJ / cm ² .

  The thickness of the film thus formed is as shown in the table.

About this film, Examples 1-6, 9, 11-16, 19, 21, Reference Example 7 , 8 , 10 , 17 , 18 , 20 , The same evaluation as the case of Comparative Examples 1-4 was performed. The results are shown in Tables 4 to 6 below.

Claims (10)

A method of manufacturing a coated wiring board comprising a wiring board and a coating covering the wiring board,
<a> A film-forming composition containing a photopolymerizable compound, a photopolymerization initiator, a resin having a carboxyl group, and an organic compound having a melting point and not having photopolymerizability is disposed on the wiring board. In the process of forming a coating film,
<B> a step of exposing the coating film; <c> a step of developing the exposed coating film with an alkaline developer; and <d> heating the coating film after development to form the coating film. Including steps,
The melting point of the organic compound is in the range of 145 to 230 ° C .;
The temperature of the coating film is maintained at a temperature lower than the melting point of the organic compound from the time when the coating film is formed by the step <a> to the time when the exposure in the process <b> is completed. ,
In the step <b>, the first part of the coating film is irradiated with light, and the second part different from the first part of the coating film has an exposure amount that is higher than that of the first part. Irradiate the light so as to be lower, do not irradiate the third part different from the first part and the second part in the coating film,
The heating temperature of the coating film in the step <d> is T _h ≧ T _m -30 (where T _h (° C.) is the heating temperature of the coating film, and T _m is the melting point of the organic compound. A method of manufacturing a coated wiring board, wherein: The method for producing a coated wiring board according to claim 1, wherein the ratio of the organic compound is in the range of 1 to 65 mass% with respect to the solid content. The organic compound is 1,3,5-tris (2,3-epoxypropyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, hydroquinone type crystalline epoxy resin And a method for producing a coated wiring board according to claim 1, comprising one or more compounds selected from the group consisting of 4-cyclohexene-1,2-dicarboxylic acid. In the step <b>, the first portion of the coating film is irradiated with light, thereby forming a first region containing bubbles from the cured product of the first portion, and the coating film. The second part different from the first part in is irradiated with light so that the exposure amount is lower than that of the first part, and is made of a cured product of the second part and contains bubbles. The method for producing a coated wiring board according to any one of claims 1 to 3, wherein the second region is formed with no air bubbles or lower than the first region. The method for producing a coated wiring board according to any one of claims 1 to 4 , wherein the resin having a carboxyl group contains a resin having a carboxyl group and not having photopolymerizability. The coating according to any one of claims 1 to 5 , wherein the resin having a carboxyl group contains a compound having a carboxyl group and an ethylenically unsaturated group and contained in the photopolymerizable compound. A method for manufacturing a wiring board. The method for producing a coated wiring board according to any one of claims 1 to 6 , wherein the photopolymerizable compound contains a monomer having an ethylenically unsaturated group. The method for producing a coated wiring board according to any one of claims 1 to 7 , wherein the film-forming composition contains a colorant. The film-forming composition contains no colorant, or any one of claims 1 to 7, characterized in that it contains a proportion of 0.04 wt% or less coloring agent on the solid content The manufacturing method of the covering wiring board as described in any one of. Wherein in the step of <b>, with respect to the exposure amount of the first portion, the ratio of the exposure amount of the second portion, to any one of claims 1 to 9 is in the range of 1-75% The manufacturing method of the coated wiring board of description.