JP4456833B2 - One-component resist composition for inkjet and method for forming resist pattern using the same - Google Patents

Description

  The present invention relates to a solder resist for printed wiring boards used in automobiles, home appliances, etc., and a one-component resist composition used for marking ink, and a resist pattern forming method using the same, and more particularly -Pack type resist composition for printed wiring boards that is not only excellent in heat resistance and storage stability but also excellent in pencil hardness, solvent resistance, chemical resistance, and solder heat resistance, and a resist pattern using the same It relates to a method of forming.

In general, as a resist composition for a printed wiring board, from the viewpoint of high accuracy and high density, an image is formed by irradiating with ultraviolet rays and then developing, and a development type in which final curing (main curing) is performed by heat or light irradiation. Liquid solder resist compositions are widely used. Particularly in recent years, an alkali development type liquid solder resist composition using a dilute alkaline aqueous solution as a developing solution has become mainstream in consideration of environmental problems.
Examples of the alkali development type liquid solder resist composition using a dilute aqueous alkali solution as the developer include, for example, a carboxyl group obtained by adding an acid anhydride to a reaction product of a novolak type epoxy resin and an unsaturated group-containing monocarboxylic acid. The resist composition which consists of a photosensitive resin containing, a photoinitiator, a diluent, and an epoxy resin is mentioned (refer patent document 1).

However, such a liquid solder resist composition is a two-component type because the reactivity of the carboxyl group-containing photosensitive resin and the epoxy resin is high, and therefore it must be mixed before use and used within a few days. There are drawbacks.
In addition, such a liquid solder resist composition requires many processes such as coating, drying, exposure, development, and heat curing, and in those processes, a coating machine, a dryer, an exposure machine, a developing machine, There is a drawback that equipment such as a thermosetting furnace is required and the manufacturing cost increases.

  On the other hand, for marking ink, a method of pattern printing by a screen printing method and heat curing is mainly used from the aspect of concealment power. However, in the case of pattern printing by screen printing, it is necessary to produce a screen plate for each product, and there is a problem regarding the storage location of the screen plate.

On the other hand, a method of forming a solder resist by an ink jet printing method has been proposed. For example, a method of creating a resist pattern by drawing a resist ink with an inkjet printer and drying it has been proposed (see Patent Document 2).
However, while the ink viscosity of the screen printing method is 2,000~15,000mPa · s (25 ℃), since the ink viscosity of the ink jet is low, 10~120mPa · s (25 ℃), such an inkjet In the method based on the printing method, the ink viscosity is further lowered by the heat during drying, and blemishes are generated. Therefore, sufficient pattern accuracy cannot be obtained and practical use has not been achieved.

In addition, when the application viscosity of the ink used for such an ink jet is less than 5 mPa · s, it drops and leaks naturally from the ink jet head, and when it exceeds 20 mPa · s, it is difficult to discharge from the ink jet head. Therefore, it is necessary to make the viscosity 5 to 20 mPa · s. For this reason, high viscosity ink is applied by heating the head. However, for example, even if the ink is stable at 80 ° C., the subsequent thermosetting temperature becomes high, and the substrate is deteriorated and the volatilization of components such as initiators is increased. Is suitable.
JP 61-243869 (Claims) JP-A-7-263845 (Claims)

The present invention has been made in view of the above-described problems, and its main purpose is not only excellent in workability and storage stability, but also pencil hardness, solvent resistance, chemical resistance, solder heat resistance. Another object of the present invention is to provide an ink jet one-part resist composition for printed wiring boards that is excellent in performance.
Another object of the present invention is to provide a method for producing a high-precision, high-density resist pattern at low cost with good workability without using expensive equipment, using such a resist composition. is there.

In order to achieve the above object, as a first aspect of the present invention, (A) an allyl monomer having two or more allyl groups in one molecule and having a viscosity of 30 mPa · s or less at 50 ° C., (B ) 1 to 2 acryloyl groups in one molecule and a viscosity of 10 mPa · s or less at 50 ° C., (C) 3 or more acryloyl groups in one molecule and a viscosity of 50 ° C. A one-component resist composition for inkjet, comprising: an acryloyl monomer of 30 mPa · s or less, (D) a photopolymerization initiator, (E) an antioxidant, (F) a pigment, and (G) an organic solvent. Things are provided.
As a preferred embodiment, (H) two or more unsaturated double bonds per molecule are added to the resist composition, and a solid resin is added at room temperature (15-30 ° C.). A one-component resist composition for ink jet is provided.
Furthermore, according to the other aspect of this invention, the said resist composition is pattern-printed with the inkjet printer on the printed wiring board surface, and the coating film is partially hardened by irradiation of an active energy ray at the time of printing or after printing, and is printed. There is provided a method of forming a resist pattern, which prevents bleeding of the subsequent composition, and then thermally cures at 100 ° C. or higher to form a resist pattern.

According to the present invention, excellent storage stability as a one-part composition, having the coating properties suitable for ink jet printers with a low viscosity, one more liquid jet ink having a coating film properties as a solder resist and marking ink A mold resist composition can be provided.
Furthermore, according to the one-component resist composition of the present invention, since it can be suitably used for ink jet printing, the process can be simplified, the productivity can be improved, the maintenance cost of the equipment can be reduced, and the cost can be reduced. become.

  As a result of intensive studies to solve the above problems, the inventor has (A) an allyl monomer having two or more allyl groups in one molecule and having a viscosity of 30 mPa · s or less at 50 ° C., (B ) 1 to 2 acryloyl groups in one molecule and a viscosity of 10 mPa · s or less at 50 ° C., (C) 3 or more acryloyl groups in one molecule and a viscosity of 50 ° C. A composition comprising an acryloyl monomer having a viscosity of 30 mPa · s or less, (D) a photopolymerization initiator, (E) an antioxidant, (F) a pigment, and (G) an organic solvent. The present invention has been completed by finding that it has excellent dischargeability, excellent stability as a one-component composition, and sufficient cured coating film properties.

  Specifically, in the composition of the present invention, the photopolymerization initiator (D) in the composition generates a photoradical by irradiation with active energy rays during printing or after printing, and this photoradical is converted into an allyl monomer ( A) acts on the acryloyl monomer (B) and the acryloyl monomer (C) to cause partial polymerization to increase the viscosity, thereby preventing the composition from being printed and then heating at 100 ° C. or higher. By performing (main curing), thermal polymerization or oxidative polymerization of unreacted acryloyl monomers (B) and (C) occurs, and further, unreacted allyl groups are also copolymerized in a chain to obtain heat resistance.

Hereinafter, the present invention will be described in detail.
The allyl monomer (A) used in the present invention has two or more allyl groups in one molecule and has a viscosity of 30 mPa · s or less at 50 ° C., such as diallyl phthalate or diallyl isophthalate. Diallyl terephthalate, trimethylolpropane diallyl ether, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitic acid and the like.
When an allyl monomer having a viscosity of more than 30 mPa · s at 50 ° C. is used, an acryloyl monomer (B) having 1 to 2 acryloyl groups in one molecule described later and having a viscosity of 10 mPa · s or less at 50 ° C. Even if an appropriate amount of organic solvent (G) is added and diluted, the viscosity of the ink becomes so high that it is difficult to be ejected from the inkjet head, which is not preferable. In addition, when a monofunctional allyl monomer is used, it is difficult to form a three-dimensional structure after curing and heat resistance is lowered, which is not preferable.

  Such an allyl monomer (A) may be used alone or in admixture of two or more, and its blending amount is 10 to 60 parts by mass with respect to 100 parts by mass of the nonvolatile content of the resist composition. Preferably it is 20-40 mass parts. When the amount of the allyl monomer (A) is less than 10 parts by mass, the solder heat resistance is lowered, and when it exceeds 60 parts by mass, the photocurability is lowered, which is not preferable.

As the acryloyl monomer (B) used in the present invention, a known and commonly used acryloyl monomer having 1 to 2 acryloyl groups in one molecule and having a viscosity of 10 mPs · s or less at 50 ° C. can be used. Ethylhexyl acrylate, lauryl acrylate, isostearyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-methoxyethyl acrylate, isobutyl acrylate, t-butyl acrylate, butoxyethyl acrylate, methyl triglycol acrylate, cyclohexyl acrylate, 2- Ethylhexyl carbitol acrylate, 4-hydroxybutyl acrylate, isobornyl acrylate, ethyl carbitol acrylate, 3-methoxybutyl acrylate Rate, methoxypropylene glycol acrylate, benzyl acrylate, phenoxyethyl acrylate, 1,3-butylene glycol diacrylate, 1,5-pentanediol diacrylate, neopentyl glycol diacrylate, tetrahydrofurfuryl acrylate, 1,6 hexanediol diacrylate , Diethylene glycol diacrylate, triethylene glycol diacrylate, 4-acryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-acryloyloxymethyl-2-isobutyl-2-ethyl-1,3-dioxolane, 4-acryloyl Examples include oxymethyl-2-cyclohexylene 1,3-dioxolane.
When an acryloyl monomer (B) having a viscosity of more than 10 mPa · s at 50 ° C. is used, even if an appropriate amount of an organic solvent (G) described below is added and diluted, the viscosity of the ink becomes too high and is discharged from the inkjet head. It becomes difficult and is not preferable. Moreover, when only the trifunctional or higher functional acryloyl monomer (C) described later is used, the coating film becomes too hard or the adhesiveness is lowered.

  Such acryloyl monomer (B) may be used alone or in admixture of two or more, and its blending amount is 2 to 20 parts by mass with respect to 100 parts by mass of the nonvolatile content of the resist composition. Preferably it is 5-15 mass parts. When the amount of the acryloyl monomer (B) is less than 2 parts by mass, the photocurability is lowered, and when it exceeds 15 parts by mass, the solder heat resistance is lowered, which is not preferable.

As the acryloyl monomer (C) used in the present invention, a known and commonly used acryloyl monomer having 3 or more acryloyl groups in one molecule and a viscosity of 30 mPs · s or less at 50 ° C. can be used, for example, trimethylolpropane. Examples include triacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, and their EO adducts.
When an acryloyl monomer having a viscosity of more than 30 mPa · s at 50 ° C. is used, the acryloyl monomer (B) having 1 to 2 acryloyl groups in one molecule and having a viscosity of 10 mPa · s or less at 50 ° C. Even if an appropriate amount of an organic solvent (G) described later is added and diluted, the viscosity of the ink becomes too high and it is difficult to eject the ink from the inkjet head, which is not preferable. In addition, when only the acryloyl monomer (B) having 1 to 2 acryloyl groups in one molecule is used, it is difficult to form a three-dimensional structure after curing and heat resistance is lowered, which is not preferable.

  Such acryloyl monomer (C) may be used alone or in admixture of two or more, and its blending amount is 20 to 65 parts by mass with respect to 100 parts by mass of the nonvolatile content of the resist composition, Preferably it is 10-40 mass parts. When the amount of the acryloyl monomer (C) is less than 10 parts by mass, the photocurability is lowered, and when it exceeds 40 parts by mass, the coating film is hardened and the curing distortion is increased, or the solder heat resistance is decreased. Absent.

As the photopolymerization initiator (D) used in the present invention, known and commonly used photopolymerization initiators can be used. For example, benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, acetophenones such as 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2 Aminoacetophenones such as morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, N, N-dimethylaminoacetophenone; 2-methylanthraquinone 2-ethyl Anthraquinones such as nthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; acetophenone dimethyl Ketals such as ketals and benzyldimethylketals; benzophenones such as benzophenone and 4,4′-bisdiethylaminobenzophenone or xanthones; 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 2-trichloromethyl-5-styryl- Halomethyloxadiazole compounds such as 1,3,4-oxadiazole and 2-trichloromethyl-5- (p-cyanostyryl) -1,3,4-oxadiazole; (Trichloromethyl) -6- (p-methoxy-phenylvinyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6-p-methoxystyryl-s-triazine, 2,4-bis And halomethyl-s-triazine compounds such as (trichloromethyl) -6- (1-p-dimethylaminophenyl-1,3-butadienyl) -s-triazine.
Such known and commonly used photopolymerization initiators can be used alone or as a mixture of two or more thereof, and further, N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl- Photoinitiator aids such as tertiary amines such as 4-dimethylaminobenzoate, triethylamine, triethanolamine can be added. In addition, a titanocene compound such as CGI-784 (manufactured by Ciba Specialty Chemicals Co., Ltd.) having absorption in the visible light region can also be added to promote the photoreaction. The photopolymerization initiator (D) is not particularly limited, and any photopolymerization initiator can be used as long as it absorbs light in the ultraviolet or visible light region and radically polymerizes a photosensitive unsaturated double bond. It is not limited to initiators and photoinitiators, and can be used.

  Such photopolymerization initiators (D) may be used alone or in combination of two or more, and the blending amount is 1 to 4 parts by mass with respect to 100 parts by mass of the nonvolatile content of the resist composition. Yes, preferably 2 to 3 parts by mass. If the blending amount of the photopolymerization initiator (D) is less than 1 part by weight, the photocurability is lowered.

  As the antioxidant (E) used in the present invention, known and usual antioxidants can be used. For example, guanamines such as dicyandiamide, o-tolylbiguanide, guanamine, acetoguanamine, benzoguanamine; melamine, 2,4-ethyldiamino -Triazines such as -s-triazine, 2,4-ethyldiamino-6-tolyl-s-triazine, 2,4-ethyldiamino-6-xylyl-s-triazine; benzotriazole, benzimidazole, benzothiazole, indazole, Heterocyclic amines such as phthalazone and 3-amino-1,2,4-triazole; phenolic antioxidants such as 2,6-di-t-butyl-p-cresol; dilauryl-3,3′-dithiopropio Sulfur-based antioxidants such as nates; Phosphorus-based oxidations such as triphenyl phosphite Sealing agent, and the like.

  Such antioxidant (E) may be used alone or in admixture of two or more, and the blending amount is 0.1 to 4 parts by mass with respect to 100 parts by mass of the nonvolatile content of the resist composition. Preferably, it is 0.5-2 mass parts. When the blending amount of the antioxidant (E) is less than 0.5 parts by mass, oxidation of the copper foil occurs, peeling or insulation failure occurs, and when it exceeds 2 parts by mass, the photocurability lowering of the lower part of the coating film occurs, It is not preferable.

The pigment (F) used in the present invention includes a red pigment anthraquinone pigment, perylene pigment; a yellow pigment disazo pigment, an isoindoline pigment; a green pigment halogenated phthalocyanine pigment; a blue pigment phthalocyanine pigment. Black carbon carbon, aniline black, iron oxide; white pigment titanium oxide, aluminum oxide, and the like. In addition, publicly known and commonly used extender pigments such as barium sulfate, calcium carbonate, and silica can be used.
Such a pigment (F) may be used alone or in admixture of two or more, and its blending amount is 0.1 to 30 parts by weight with respect to 100 parts by weight of the nonvolatile content of the resist composition. The amount is preferably 0.5 to 2 parts by mass. When the blending amount of the pigment (F) is less than 0.1 parts by mass, the visibility is inferior, and when it exceeds 30 parts by mass, the photocuring property at the lower part of the coating film is lowered, which is not preferable.

  Examples of the organic solvent (G) used in the present invention include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, propylene glycol monomethyl ether, propylene glycol mono Glycol ethers such as ethyl ether; Acetic esters such as ethyl acetate, butyl acetate and cellosolve acetate; Alcohols such as ethanol and propanol; Aliphatic hydrocarbons such as pentane, octane and decane; Petroleum ether, petroleum naphtha, hydrogenated Examples include petroleum solvents such as petroleum naphtha and solvent naphtha.

Such an organic solvent (G) is used to dissolve the photopolymerization initiator (D), the antioxidant (E), and the resin (F), and to adjust the resist composition to a viscosity suitable for inkjet printing. These may be used alone or in combination of two or more. The compounding quantity of these organic solvents (G) is 0.1-15 mass parts with respect to 100 mass parts of non volatile matters of a resist composition, Preferably it is 5-10 mass parts. If the blending amount of the organic solvent (G) is less than 0.1 parts by mass, there is no viscosity diluting effect, and if it exceeds 15 parts by mass, swelling or the like occurs during photocuring, which is not preferable.
Moreover, it is preferable that the boiling point of these organic solvents (G) is 30 degreeC or more higher than the heating temperature of an inkjet head. When the boiling point of the organic solvent (G) is lower than the above temperature, bubbles are likely to be generated in the inkjet head, and the coating property is lowered, which is not preferable.

  Furthermore, low molecular weight methacryloyl monomers such as ethylene glycol dimethacrylate and ethyl methacrylate can also be used as a diluent. These methacryloyl monomers have low sensitivity to active energy, and when added in a large amount, the photocurability is lowered. However, unreacted methacryloyl monomers are volatilized when heated and act in the same manner as an organic solvent.

The resist composition of the present invention has (H) two or more unsaturated double bonds in one molecule and can be blended with a solid resin at room temperature in order to alleviate distortion of the cured coating film and improve heat resistance. .
As the resin (H) having two or more unsaturated double bonds in one molecule and solid at room temperature (15 to 30 ° C.), epoxy acrylate, urethane acrylate, polyester acrylate, triallyl isocyanurate resin, diallyl phthalate Resin, diallyl isophthalate resin, diallyl terephthalate resin, etc. are mentioned.

  The compounding quantity of such solid resin (H) is 5 mass parts or less with respect to 100 mass parts of non volatile matters of a resist composition. When the blending amount of the solid resin (H) exceeds 5 parts by mass, the viscosity of the resist composition is increased and the ink jet coating property is decreased, which is not preferable.

The resist composition of the present invention may contain various known and commonly used additives, for example, various additives such as an antifoaming agent, an adhesion-imparting agent, a leveling agent, and a pigment dispersant, as necessary.
The compounding quantity of these additives is 5 mass parts or less with respect to 100 mass parts of non volatile matters of a resist composition. When the compounding amount of the additive exceeds 5 parts by mass, the viscosity of the resist composition is increased, and the ink jet coating property is deteriorated.

  Furthermore, in order to improve the thermosetting property, a known and commonly used organic peroxide can be added. For example, isobutyl peroxide, α, α′-bis (neodecanoylperoxy) diisopropylbenzene, cumylperoxydi Carbonate, di-n-propylperoxydicarbonate, diisopropylperoxydicarbonate, di-sec-butylperoxydicarbonate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, bis (4- t-butylcyclohexyl peroxydicarbonate, 1-cyclohexyl-1-methylethylperoxyneodecanoate, di-2-ethoxyethylperoxydicarbonate, di (2-ethylhexyl) dicarbonate, t-hexylperoxyneodecane Noate, dimethoxybutyl -Oxydicarbonate, t-butylperoxyneodecanoate, t-hexylperoxypivalate, t-butylperoxypivalate, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroylper Oxide, stearoyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, succinoxide, 2,5-dimethyl-2,5-di (ethylhexanoylperoxy) hexane , T-hexylperoxy-2-ethylhexanoate, t-butylperoctoate, 4-methylbenzoyl peroxide, t-butylperoxy-2-ethylhexanoate, m-toluoyl peroxide, benzoylperoxide Oxide, t-butylperoxy Butyrate, 1,1-bis (t-butylperoxy) 2-methylcyclohexane, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexyl) Peroxy) cyclohexane, 1,1- (t-butylperoxy) -3,3,5-trimethylcyclohexane and the like.

  The amount of such an organic peroxide is 0.5 parts by mass or less with respect to 100 parts by mass of the nonvolatile content of the resist composition. When the amount of the organic peroxide exceeds 0.5 parts by mass, the storage stability is lowered, which is not preferable.

  The one-component resist composition of the present invention obtained by blending the components as described above becomes uniform using a stirrer or a disperser, for example, a disperser such as a roll mill, a sand mill, a ball mill or an attritor. Until mixed and dispersed.

According to the one-component resist composition of the present invention thus adjusted, pattern printing is performed on the surface of the printed board with an inkjet printer, and the coating is partially cured by irradiation with active energy rays during printing or after printing. The subsequent composition can be prevented from bleeding and then thermally cured (mainly cured) at 100 ° C. or higher, preferably 100 to 180 ° C., more preferably 150 ° C., to obtain a resist pattern.
In addition, you may perform irradiation of the said active energy ray and thermosetting in the air or in inert gas atmosphere.

  Further, as the irradiation source of the active energy ray, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, a metal halide lamp, or the like is suitable, and a laser beam or the like can also be used as the active energy ray.

  Hereinafter, the present invention will be specifically described with reference to examples and the like, but the present invention is not limited to these examples. In the following description, “part” means part by mass unless otherwise specified.

The composition blended at the ratio shown in Table 1 was dispersed for 8 hours with a sand mill, filtered through a 1 μm filter, a one-component solder resist composition for ink jet (Examples 1 to 5), and a marking ink composition (implemented). Example 6) was obtained.

A substrate was prepared from the thus obtained one-pack type resist composition for inkjet according to the steps shown in Table 2.
In addition, evaluation of marking ink evaluated the coating-film characteristic on a soldering resist using the soldering resist application board | substrate.

In addition, as a comparison, the thermosetting solder resist S-222 manufactured by Taiyo Ink Manufacturing Co., Ltd. was diluted with a solvent and filtered so that it could be applied by inkjet. However, the nonvolatile content was 5 wt%, and a sufficient film thickness could not be secured. The resist was not cured due to the large amount of solvent. In addition, the UV-curable solder resist UVR-150 was diluted with a diluent UVR reducer and filtered so that it could be similarly applied by inkjet. However, since the amount of acryloyl monomer increased, the UV-curable solder resist UVR-150 was cured even when irradiated with 2000 mJ / cm ² of UV light. Therefore, a comparative test could not be performed.

  Table 3 shows the evaluation results of Examples 1 to 5 of the one-component solder resist composition for inkjet and Example 6 of the one-component marking ink composition for inkjet.

In addition, the evaluation method of the performance test in Table 3 is as follows.
(1) Viscosity The viscosity (50 ° C.) when the resist composition of the present invention was applied with an inkjet printer was measured. (Appropriate viscosity = 5 to 20 mPa · s)
Specific gravity was measured using a hydrometer, and kinematic viscosity was measured using a Canon Fenceke viscometer.
Viscosity (mPa · s) = Kinematic viscosity (mm ² / s) × Specific gravity

(2) Coating film hardness The pencil hardness of the cured coating film on the copper foil was evaluated according to the test method of JIS K-5400.

(3) Solvent resistance The state of the coating film after the cured coating film was immersed in propylene glycol monomethyl acetate for 30 minutes was evaluated.
○: No change at all △: Only slight change ×: Significant change

(4) Chemical resistance The state of the coating film after the cured coating film was immersed in 10 wt% hydrochloric acid for 10 minutes was evaluated.
○: No change at all △: Only slight change ×: Significant change

(5) Solder heat resistance The cured coating film was immersed in a solder bath at 260 ° C. for 5 seconds in accordance with the test method of JIS C-6482, and then the coating film state after a peeling test using a cellophane tape was evaluated.
○: No peeling of coating film Δ: Slight peeling of coating film ×: Peeling of coating film

(6) Storage stability The one-pack type solder resist composition for inkjet was stored at room temperature, and the number of days until gelation was evaluated.

Claims (4)

(A) An allyl monomer having two or more allyl groups in one molecule and a viscosity of 30 mPa · s or less at 50 ° C., (B) One or two acryloyl groups in one molecule and having a viscosity of An acryloyl monomer having a viscosity of 10 mPa · s or less at 50 ° C., (C) an acryloyl monomer having 3 or more acryloyl groups in one molecule and a viscosity of 30 mPa · s or less at 50 ° C., (D) a photopolymerization initiator, E) One-component resist composition for inkjet, comprising an antioxidant, (F) a pigment, and (G) an organic solvent. The one-component resist composition for inkjet according to claim 1, further comprising (H) a resin having at least two unsaturated double bonds in one molecule and solid at room temperature. The one-component resist composition for inkjet according to claim 1 or 2, wherein the amount of the organic solvent (G) is 0.1 to 15 parts by mass with respect to 100 parts by mass of the nonvolatile content of the resist composition. The claims 1 to inkjet one-pack Katare resist composition according to any one of 3, and the pattern printed with an inkjet printer on the printed wiring board surface, the irradiation of the active energy ray to the coating film after printing during or printing A resist pattern forming method comprising: forming a resist pattern by partially curing the composition to prevent bleeding of the composition after printing, and then thermally curing at 100 ° C. or higher.