JP6529035B2 - Etching resist composition for printing, method of forming resist film, and method of manufacturing substrate having metal layer pattern - Google Patents

Description

  The present invention relates to a printing etching resist composition particularly useful for screen printing applications, a method for forming a resist film, and a method for producing a substrate having a metal layer pattern.

  The resist composition is used to form patterns of circuits, electrodes and the like used in touch panels, electronic papers and various electronic components. The main required performance of the resist composition is that the etchant resistance is high when etching the substrate after film formation, and that the pattern resolution is high and the LER (Line Edge Roughness) is low in terms of fine processing Printability such as In recent years, circuit boards for electronic devices to which these resist compositions are applied are becoming increasingly thinner, lighter and more flexible. Such a flexible substrate is susceptible to an impact or the like in a processing process such as etching, and the composition may be peeled off due to this impact, and a delicate pattern may not be formed. Resist compositions having conformability are desired.

  From the point of printability, the photoresist method is the mainstream of the pattern formation method using the resist composition. For example, in Patent Document 1, after a photosensitive resin film is formed on a substrate, the photosensitive resin film is cured by partial exposure, and then the unexposed area is removed (etched) by a development step. A fine pattern can be formed. However, in this method, in order to form a resist film, steps of placement of a mask with respect to the composition, exposure and development are essential and work is complicated.

  On the other hand, examples of conventionally known printing ink compositions include those using a rosin modified phenolic resin, rosin ester resin, maleic acid resin, petroleum resin, alkyd resin, etc. as a resin varnish, etc. Even when used as a composition, a delicate pattern may not be formed because the printed film peels entirely or partially in the etching step.

  Therefore, the present applicant has disclosed in Patent Document 2 a resist composition for a printing ink which is mainly composed of a phenol resin and further contains a thickener. In this composition, each process of exposure and development is unnecessary, so the process is simple, a film excellent in etchant resistance is obtained by heat drying, and etching is possible using an acid or the like. However, when used for forming a circuit of a flexible substrate, there have been cases in which cracks or peeling may occur in a film formed by external impact such as spray etching. Furthermore, the said resist composition is calculated | required by the improvement of printability.

JP 2008-145707 A JP, 2004-260143, A

  An object of the present invention is to provide an etching resist composition for printing, a method for forming a resist film, and a substrate having a metal layer pattern capable of forming a film excellent in printability and followability to a substrate without each step of exposure and development. It is to provide a manufacturing method of

  MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, the present inventors contain the phenol resin, the acrylic resin which has a glass transition temperature of a specific range, and the silica particle of an average primary particle diameter a specific range. The inventors have found that the above-mentioned problems can be solved by using an etching resist composition for printing of 0 or more, and the present invention has been completed.

  That is, the present invention includes the following aspects.

  Item 1. (A) Phenolic resin, (B) Acrylic resin whose glass transition temperature is in the range of -30 to 50 ° C, and (C) silica particles having an average primary particle diameter of 1 to 100 nm, the specific gravity of the composition is 1 The etching resist composition for printing which is more than 0.

  Item 2. The content of the phenolic resin (A) is 30 to 95% by mass, and the content of the acrylic resin (B) is 5 based on the total solid content of the phenolic resin (A) and the acrylic resin (B). The etching resist composition for printing according to Item 1, wherein the content of the fine particles (C) is 70% by mass and the content of the fine silica particles (C) is 1% by mass.

  Item 3. The printing resist according to claim 1, further comprising (D) a hydroxyl group-containing organic solvent, wherein the component (D) contains a hydroxyl group organic solvent having a boiling point of 190 ° C. or higher.

  Item 4. The etching resist composition for printing according to any one of Items 1 to 3, further comprising inorganic fine particles (F) having a specific gravity of 2.5 or more.

  Item 5. Item 5. The etching resist composition for printing according to any one of Items 1 to 4, further comprising a non-silicone antifoaming agent (G).

  Item 6. The resist including the process of screen-printing on the surface of the base material which has a metal layer on the surface using the etching resist composition for printing of any one of claim 1-5, and forming a resist film of a desired pattern Film formation method.

Item 7. (1) On the metal layer side of the substrate having a metal layer on the surface, screen printing is performed using the etching resist composition for printing according to any one of items 1 to 5 to form a desired resist film Process,
(2) removing the metal layer in a portion where the resist film is not formed with an etching solution, and (3) removing the resist film using a stripping solution after the step (2). The manufacturing method of the base material which has a layer pattern.

  The etching resist composition for printing of the present invention is directly applied to a substrate in a desired pattern by screen printing, and is excellent not only in printability, but also in heat resistance of a film excellent in substrate followability and warpage resistance. It can be formed by drying. The coated resist composition well protects the substrate from the etching solution without peeling during etching, and rapidly peels off by the peeling solution after the etching is completed to produce a substrate having a desired metal layer pattern. Can. In addition, the resist composition of the present invention can form a film that can sufficiently withstand printability and etching solution even by heat drying, so there is no effect of each process of exposure and development, and the process can be shortened. Play.

Etching resist composition for printing The etching resist composition for printing of the present invention is a composition particularly suitable for screen printing applications, and an acrylic resin having a phenol resin (A) and a glass transition temperature in the range of -30 to 50 ° C. It is an etching resist composition for printing which has a resin (B) and silica fine particles (C) having an average primary particle diameter of 1 to 100 nm and the specific gravity of the composition is 1.0 or more.

(A) Phenolic Resin The etching resist composition for printing of the present invention contains a phenolic resin (A).

  The phenol resin (A) is not particularly limited as long as it is a resin that is soluble in the alkaline stripping solution in the stripping step described later.

  As a phenol resin (A) used for this invention, both novolak-type phenol resin and polyvinyl phenol resin can be used, for example.

  Examples of the above novolak type phenol resin include phenol, m-cresol, o-cresol, p-cresol, 2,5-xylenol, 3,5-xylenol, resorcinol, pyrogallol, bisphenol, bisphenol-A, trisphenol, o -At least one aromatic hydrocarbon such as ethylphenol, m-ethylphenol, p-ethylphenol, propylphenol, n-butylphenol, t-butylphenol, 1-naphthol, 2-naphthol, etc. under acidic catalysis At least one selected from aldehydes such as formaldehyde, formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde and furfural, and ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone Those engaged aldehydes or ketones and polycondensation can be mentioned.

  The weight average molecular weight of the novolac type phenolic resin is preferably in the range of 200 to 200,000, more preferably 300 to 20,000. If the weight average molecular weight is less than 200, the resistance to the etching solution may be deteriorated, and if it exceeds 200,000, the solubility of the resist film after etching to the alkali stripping solution may be deteriorated.

  Examples of the polyvinyl phenol resin include o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (o-hydroxyphenyl) propylene, 2- (m-hydroxyphenyl) propylene, 2- (p-hydroxy) The polymer of 1 type (s) or 2 or more types of vinylphenol compounds, such as phenyl) propylene, is mentioned. The vinylphenol compound may have a substituent such as halogen such as chlorine, bromine, iodine, or fluorine or an alkyl substituent having 1 to 4 carbon atoms on the aromatic ring, but an unsubstituted polyvinylphenol resin is preferable.

  The polyvinyl phenol resin is usually obtained by polymerizing one or more of the vinyl phenol compounds in the presence of a radical polymerization initiator or a cationic polymerization initiator. The polyvinyl phenol resin may be partially hydrogenated. Moreover, the resin which protected some OH groups of polyvinyl phenols by t-butoxycarbonyl group, pyranyl group, a furanyl group etc. may be sufficient.

  The weight average molecular weight of the polyvinyl phenol resin is preferably in the range of 1,000 to 100,000, particularly preferably 1,500 to 50,000. If the weight average molecular weight is less than 1,000, the etchant resistance may be deteriorated, and if it exceeds 10,000, the solubility of the resist film after etching to the alkali stripping solution may take a long time, or residues may remain. There is a case.

  A commercial item can be used as said phenol resin (A), As a commercial item, MER-7966, MER-7969, MER-7971, MER-7980 (above, Meiwa Kasei Co., Ltd. make), PR is mentioned, for example. -HF-3, PR-50731 (above, Sumitomo Bakelite Co., Ltd. make) etc. are mentioned.

  In the present specification, weight-average molecular weight refers to the retention time (retention capacity) of standard polystyrene of known molecular weight, which is measured under the same conditions as retention time (retention capacity) measured using gel permeation chromatography (GPC) It is the value calculated by converting it into the molecular weight of polystyrene. Specifically, "HLC-8120GPC" (trade name, manufactured by Tosoh Corporation) is used as a gel permeation chromatograph apparatus, and "TSKgel G4000HXL", "TSKgel G3000HXL", "TSKgel G2500HXL" and "TSKgel" are used as columns. A total of four G2000HXL (trade names, all manufactured by Tosoh Corporation) are used, a differential refractometer is used as a detector, mobile phase: tetrahydrofuran, measurement temperature: 40 ° C., flow rate: 1 mL / min. It can be measured below.

(B) Acrylic Resin The etching resist composition for printing of the present invention contains an acrylic resin (B).

  The acrylic resin (B) has a glass transition temperature in the range of −30 to 50 ° C. in terms of peel protection (impact resistance) and flexibility in connection with external impact in the working process. It is characterized by the characteristics, and more preferably in the range of -20 to 40 ° C. When the glass transition temperature is lower than -30 ° C, the dried film becomes too soft and tackiness may occur, which may cause problems in subsequent handling operations. If the temperature is higher than 50 ° C., the resin may become too hard to exhibit flexibility sufficiently.

  Here, in the present specification, the dry coating film means a finger dry state defined in JIS K 5600-1-1, that is, a finger does not touch the center of the coating surface with a finger and the finger does not get dirty. It is a dried coating film. On the other hand, the coating film in which the tack has occurred is a state in which the coating film has not reached the above-described touch-dry state.

  Moreover, in the present specification, the glass transition temperature Tg of the acrylic resin (B) is a value calculated by the following equation.

1 / Tg (K) = W1 / T1 + W2 / T2 +... Wn / Tn
Tg (° C.) = Tg (K) -273
In the formula, W1, W2, ... Wn are mass fractions of respective monomers, and T1, T2 ... Tn are glass transition temperatures Tg (K) of homopolymers of the respective monomers.

  In addition, the glass transition temperature of the homopolymer of each monomer is described in POLYMER HANDBOOK Fourth Edition, J. Org. Brandrup, E. h. Immergut, E., et al. A. The glass transition temperature of a monomer which is a value according to Grulke (1999) and which is not described in the literature is static when a homopolymer of the monomer is synthesized to have a weight average molecular weight of about 50,000. Let it be the glass transition temperature.

  The static glass transition temperature is measured, for example, by taking a sample in a measuring cup using a differential scanning calorimeter “DSC-50Q type” (trade name of Shimadzu Corporation) and vacuum suctioning to completely remove the solvent. It can be measured by measuring the change in calorific value in the range of -100 ° C to 150 ° C at a heating rate of ° C / min and making the transition point from the initial baseline on the low temperature side a static glass transition temperature .

  The acrylic resin (B) can be produced by various methods conventionally known, and can be obtained, for example, by polymerizing a polymerizable unsaturated monomer by a solution polymerization method or the like in an organic solvent.

  Examples of the polymerizable unsaturated monomer include, for example, α, β-ethylenically unsaturated acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid and fumaric acid; methyl (meth) acrylate, ethyl (meth) acrylate, propyl ( Esters of (meth) acrylic acid such as meta) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate And other polymerizable unsaturated monomers such as styrene, (meth) acrylonitrile, (meth) acrylamide and the like.

  Also, as used herein, "(meth) acrylate" means acrylate or methacrylate. "(Meth) acrylic acid" means acrylic acid or methacrylic acid. Also, "(meth) acryloyl" means acryloyl or methacryloyl. Also, "(meth) acrylamide" means acrylamide or methacrylamide.

  It is preferable that an acrylic resin (B) has an acid value from the point of alkaline peelability.

  In order to obtain such an acrylic resin (B) having an acid value, an α, β-ethylenically unsaturated acid can be suitably used as a copolymerizable monomer component.

  The α, β-ethylenically unsaturated acid can be used in such an amount that the acid value of the acrylic resin (B) is generally in the range of 10 to 650 mg KOH / g.

  The weight average molecular weight and the acid value of the acrylic resin are particularly preferably in the following ranges.

  The acid value of the acrylic resin (B) is preferably 100 to 600 mg KOH / g, more preferably more than 120 and 500 mg KOH / g or less, particularly preferably 125 to 300 mg KOH / g from the viewpoint of etching solution resistance and alkaline peelability. Within the range is suitable.

  The weight average molecular weight of the acrylic resin (B) is preferably in the range of 3,000 to 150,000, more preferably 5,000 to 100,000, from the viewpoint of etching solution resistance, impact resistance and alkali peelability. ing. If the weight average molecular weight is less than 3,000, the etching solution resistance and impact resistance may be insufficient, and if it exceeds 150,000, it may be difficult to peel off with the alkaline stripping solution.

(C) Silica fine particles The etching resist composition for printing of the present invention contains silica fine particles (C) having an average primary particle diameter of 1 to 100 nm.

  The silica fine particles (C) used in the present invention are characterized in that those having an average primary particle diameter in the range of 1 to 100 nm are used from the viewpoints of substrate followability, cracking prevention and printability. Preferably in the range of 2 to 50 nm, more preferably 5 to 20 nm is suitable. When the average primary particle diameter is larger than 100 nm, there is a possibility that the resolution and the printing appropriate viscosity may not be developed, which is not preferable. If the average primary particle size is smaller than 1 nm, the dispersibility in the resist composition may be deteriorated, which is not preferable.

  Examples of the silica fine particles (C) include colloidal silica fine particles and powdery fine particle silica.

  The colloidal silica fine particles are obtained by dispersing ultrafine particles of silica in a dispersion medium.

  As the dispersion medium, water; alcohol solvents such as methanol, ethanol, isopropanol, n-propanol, isobutanol and n-butanol; polyhydric alcohol solvents such as ethylene glycol; ethylene glycol monoethyl ether, ethylene glycol monobutyl ether and the like Derivatives thereof; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and diacetone alcohol; and monomers such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate and tetrahydrofurfuryl acrylate. Among them, water, methanol, ethanol, isopropanol and the like are preferable from the viewpoint of easiness of production.

  As colloidal silica fine particles, methanol silica sol, IPA-ST, MEK-ST, NBA-ST, XBA-ST, DMAC-ST, PGM-ST, Snowtex UP, Snowtex OUP, Snowtex 20, Snowtex 40, Snow Tex 40-O, Snowtex C, Snowtex N, Snowtex O, Snowtex 50, Snowtex OL (trade names, manufactured by Nissan Chemical Industries, Ltd.), and the like.

  Commercial products of powdered fine particle silica include Aerosil 130, Aerosil 300, Aerosil 380, Aerosil TT600, Aerosil OX50 (all trade names, manufactured by Nippon Aerosil Co., Ltd.), E220A, E220 (trade names, manufactured by Nippon Silica Industries Co., Ltd.) And SYLYSIA 470 (trade names, manufactured by Fuji Silysia Chemical Ltd.) and the like.

  These fine silica particles may be treated with a hydrolyzable silane compound, a polymerizable silane compound or the like.

  Commercially available silica fine particles treated with hydrolyzable silane compounds and the like may be used. For example, Aerosil R972, Aerosil R974, Aerosil R976, Aerosil R9200, Aerosil R976S, Aerosil RX50, Aerosil NAX50, Aerosil RX50, Aerosil NAX50 Aerosil NX90G, Aerosil EX200, Aerosil RX300, Aerosil R812, Aerosil R812 S, Aerosil R200, Aerosil RY200, Aerosil RY200 S, Aerosil RY300, NA50, Aerosil RA200 H, Aerosil NA50 Y, Aerosil RA200 HS, Aerosil NA200 Y, Aero R 7107, Aero R 7 Etc.

  The average primary particle diameter of the silica fine particles in the present invention is a value obtained by observing the silica fine particles with a scanning electron microscope and averaging the maximum diameters of 20 fine particle silicas on a straight line randomly drawn on an electron micrograph. It is.

  The resist composition of the present invention improves the viscosity (pseudoplasticity) of the composition from immediately after screen printing to drying by containing silica fine particles having an average primary particle diameter in a specific range, and the film does not spread. Since the desired pattern can be retained, the pigment concentration can be relatively suppressed, and a film excellent in printability can be formed by heat drying.

(D) Organic solvent The etching resist composition for printing of the present invention may contain an organic solvent, and among them, a hydroxyl group-containing organic solvent can be suitably used from the viewpoint of printability and printing workability. The hydroxyl group-containing organic solvent is not particularly limited as long as the number of hydroxyl groups in one molecule is 1 or more, but the number of hydroxyl groups in one molecule is one hydroxyl group-containing organic solvent (d1) and two or more And a hydroxyl group-containing organic solvent (d2).

  As the hydroxyl group-containing organic solvent (d1), for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol monohexyl ether, ethylene glycol monocyclohexyl Ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monotert-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol Recall monopentyl ether, diethylene glycol monohexyl ether, diethylene glycol monocyclohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol monobutyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol Monopropyl ether, triethylene glycol monobutyl ether, triethylene glycol monopentyl ether, triethylene glycol monohexyl ether, triethylene glycol monocyclohexyl ether, triethylene glycol monophenyl ether, triethylene glycol mo Ethylene glycol ethers such as benzyl ether and triethylene glycol monobutyl ether; and propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol monopentyl ether, propylene glycol monohexyl ether, Propylene glycol monocyclohexyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monopentyl ether, dipropylene glycol monohexyl ether, dipropylene glycol Recall monocyclohexyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tripropylene glycol monopentyl ether, tripropylene glycol monohexyl ether and tripropylene glycol monochromic Propylene glycol ethers such as hexyl ether; 3-methoxy-3-methyl-1-butanol and the like.

  As the hydroxyl group-containing organic solvent (d2), for example, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 2-methyl-1,3-propanediol, 1,3-propanediol, 1,2-propanediol Butanediol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,3-butanediol, neopentyl glycol, 1,2-pentanediol, 1,5-pentanediol, 3-methyl- 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, octanediol, 1,4-butylenediol, 1,4-cyclohexanedimethanol, glycerin and trimethylolpropane.

  Among them, in view of printability and printability (viscosity), a hydroxyl group-containing organic solvent (d1) having one hydroxyl group in one molecule is preferable, and in view of printability and printability, the boiling point is 190 ° C. Above, more preferably in the range of 195 to 300 ° C. is suitable. The above range is suitable in terms of printing workability (particularly continuous printing), since it suppresses bleeding of the resist film and suppresses the drying speed appropriately to prevent the plate from drying too fast. Specifically, ethylene glycol monobutyl ether, ethylene glycol isobutyl ether, ethylene glycol tertiary butyl ether, diethylene glycol monobutyl ether, diethylene glycol isobutyl ether and triethylene glycol monobutyl ether are particularly preferable.

  These hydroxyl group-containing organic solvents may be used alone or in combination of two or more.

(E) Inorganic fine particles The etching resist composition for printing of the present invention may contain inorganic fine particles (E) other than the component (C).

  The inorganic fine particles (E) are not particularly limited. Group II metal elements such as beryllium, magnesium, zinc and calcium, Group IV metal elements such as titanium, tin, zirconium and lead Vb such as antimony and vanadium Group metal elements and various metal oxides such as Group VI metal elements such as chromium, molybdenum and tungsten, and Group VIII metal elements such as iron, cobalt and nickel; or barium sulfate, dibasic lead phosphite, There may be mentioned fine particles of basic lead sulfate.

  The average primary particle diameter of the inorganic fine particles (E) is preferably in the range of 1 to 100 nm, more preferably 5 to 70 nm, from the viewpoints of substrate followability, anti-cracking and printability. The average primary particle size can be determined in the same manner as the method described in the section of the silica fine particles (C).

  The inorganic fine particles (E) make the specific gravity of the etching resist composition for printing of the present invention 1.0 or more with a relatively small amount of use, and from the viewpoint of printing workability, printability and compliance to a substrate, The specific gravity is suitably 2.5 g / ml or more, preferably in the range of 4.0 to 8.0 g / ml.

  The specific gravity of the inorganic fine particles can be measured in accordance with JIS-K5101 (1991), which is a value measured by a liquid immersion method using a pycnometer.

  The inorganic fine particles may be one that colors the resist composition as long as the specific gravity is within the above range.

(F) Antifoamer The etching resist composition for printing of the present invention may contain an antifoamer (G). The antifoaming agent is not particularly limited as long as it has antifoaming properties capable of suppressing foaming of the composition, but the resist composition of the present invention is a non-silicone antifoaming agent of the present invention. It can be particularly preferably used because it can form a resist film having good antifoaming properties and excellent smoothness. The antifoaming agent may be used alone or in combination of two or more.

  The non-silicone antifoaming agent is not particularly limited as long as the raw material substantially does not contain a silicon compound and exhibits foam-breaking or defoaming effects, but specifically, paraffin-based mineral oil and acrylic acid alkyl ester co-ester Examples thereof include acrylic copolymers such as polymers, methacrylic acid alkyl ester copolymers, alkyl vinyl ethers, acrylic copolymers, and foam-blowing polymers. From the viewpoint of printing workability such as releasability, defoaming properties and printing properties, the antifoaming agent is particularly preferably a (meth) acrylic acid alkyl ester copolymer.

Other Components The etching resist composition for printing of the present invention is an organic solvent other than the above-mentioned hydroxyl group-containing organic solvent (D), a coloring pigment, an extender, a surface control agent (acrylic, vinyl based) as long as the performance is not impaired. And the like), conventional paint additives such as rheology control agents, rust inhibitors, and plasticizers can be contained singly or in combination of two or more.

  Examples of the organic solvent other than the component (D) include ketones, aromatic hydrocarbons, glycol ether acetates, ethers, aliphatic hydrocarbons, petroleum solvents and the like. More specifically, hydrocarbons such as toluene, xylene, solvent naphtha, normal hexane, cyclohexane and normal heptane, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and diacetone alcohol, ethyl acetate, butyl acetate, Esters such as cellosolve acetate, methyl lactate, butyl lactate and ethyl lactate, ethylene glycol monomethyl ether acetate, polopylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, glycol esters such as dipropylene glycol monomethyl ether acetate System, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether Ethers such as ter, etc., ethyl 3-ethoxypropionate, dibasic acid esters, dimethyl carbonate, N, N-dimethylformamide, N-methyl-2-pyrrolidone, 1,3-dioxolane, γ-butyrolactone, dimethyl sulfoxide , Dimethylformamide and the like.

  Examples of the color pigments include zinc flower, carbon black, molybdenum red, Prussian blue, cobalt blue, azo pigments, phthalocyanine pigments, quinacridone pigments, isoindoline pigments, graphene pigments, perylene pigments, dioxazine pigments And pigments such as diketopyrrolopyrrole pigments.

  As other color pigments, aluminum paste, pearl powder, graphite, luster pigments such as MIO and the like can be mentioned as typical examples.

  Carbon black and / or phthalocyanine pigments are preferred in view of their ability to be colored with a relatively small amount of use and visibility at the time of inspection.

  These color pigments may be added directly to the composition, or may be mixed with a dispersing agent and a dispersing resin, dispersed and pasted, and then incorporated into a paint. The dispersant, the dispersing resin and the dispersing method may be known ones.

Content of Each Component of Resist Composition The content of each component in the etching resist composition for printing of the present invention is not particularly limited, but the following range is preferable from the viewpoint of the following resist performance and printability .

  In the resist composition of the present invention, the ratio of the content of each component described above is as follows based on the total solid content of the component (A) and the component (B).

  The content of the phenol resin (A) is suitably in the range of 30 to 95% by mass, preferably 40 to 93% by mass, and more preferably 50 to 90% by mass, from the viewpoint of etching solution resistance.

  The content of the acrylic resin (B) is preferably 5 to 70% by mass, more preferably 7 to 60% by mass, and still more preferably 10 to 50% by mass from the viewpoint of flexibility.

  The content of the silica fine particles (C) is preferably in the range of 1 to 50% by mass, preferably 5 to 40% by mass, and more preferably 10 to 30% by mass from the viewpoint of printability.

  When the hydroxyl group-containing organic solvent (D) is contained among the organic solvents, the solid content of the resist composition is preferably in the range of preferably 20 to 90% by mass, more preferably 30 to 70% by mass. When the content of the hydroxyl group-containing organic solvent (D) in the organic solvent is within the above range, the bleeding of the resist film is suppressed and the drying speed is appropriately suppressed to prevent the plate from drying too fast. Printability can be further improved.

  When the inorganic fine particles (E) are contained, the content is preferably 1 to 70% by mass, more preferably 2 to 50% by mass, and still more preferably 5 to 40% by mass from the viewpoint of printability and printability. Range is suitable.

  Here, the content ratio of the solid content of the silica fine particles (C) and the inorganic fine particles (E) is based on the total amount of the silica fine particles (C) and the inorganic fine particles (E) from the viewpoint of printability and substrate followability. Preferably in the range of 10/90 to 50/50, more preferably 30/70 to 45/55 is suitable.

  When the non-silicone antifoaming agent (F) is contained, it is preferably 0.1 to 20% by mass, more preferably 0.5 to 15% by mass from the viewpoint of surface smoothness and printing properties such as plate separation. Within the range of is suitable.

  When a color pigment is contained, it is not particularly limited as long as a desired design can be obtained, but for example, the range of 1 to 100% by mass, preferably 1 to 50% by mass is suitable.

  In the present invention, the etching resist composition of the present invention can be obtained by mixing and dispersing the above-described components and other components according to a conventional method such as using a disperser such as a disper, sand mill, roll mill or ball mill. it can. At this time, additives such as a dispersant and a plasticizer may be appropriately added to the composition, if necessary.

  The specific gravity of the resist composition obtained as described above is characterized by being 1.0 or more from the viewpoint of stability and printability of the composition, and preferably in the range of 1.1 to 1.5. Inside is suitable. If the specific gravity of the composition is less than 1.0, the printing workability may be deteriorated, a desired printing pattern may not be obtained, and the substrate followability and impact resistance may be insufficient.

  In the present specification, the specific gravity of the etching resist composition for printing may be a value as measured according to the 4.2 specific gravity cup method of JIS-K7232 (1986).

  The viscosity of the etching resist composition for printing is not particularly limited as long as it can be printed, but from the viewpoint of the balance between mechanical strength, printability, printability, and etchant resistance of the etching resist composition for printing. Usually, 1 Pa · s or more, more preferably in the range of 2 to 200 Pa · s is suitable.

  20-90 mass% is preferable, and, as for solid content of the etching resist composition for printing of this invention, 30-80 mass% is more preferable. If the solid content is within the above range, the solvent amount is suppressed to prevent the resist film from exuding, the drying speed of the resist solution is appropriately suppressed, the plate is prevented from drying too fast, and the printing workability is improved. It is suitable in point.

  The etching resist composition for printing of the present invention contains a phenol resin (A), an acrylic resin (B) having a glass transition temperature within a specific range, and a silica fine particle (C) having a particle diameter within a specific range. By being the above composition, not only it is excellent in printability but the effect that it is excellent in base-material flattery nature and crack resistance is produced.

  Even if the substrate is a flexible substrate that is easily deformed by an external impact such as vibration due to etching processing, the excellent in substrate followability does not cause the coating to peel off during etching of the coated resist composition. And the metal of the substrate having the metal layer can be well protected from the etching solution to form a desired pattern. That is, the dry film of the etching resist composition for printing of the present invention has adhesion and flexibility enough to withstand an impact received in the process of manufacturing an electronic circuit, such as vibration due to etching, etc. Excellent.

  In addition, the resist composition of the present invention is excellent in substrate followability, and can be rapidly peeled off by a peeling solution after completion of etching to produce a substrate having a desired metal layer pattern. In addition, the resist composition of the present invention has the effect of being able to shorten the process since it can obtain a film sufficiently resistant to the printability and the etching solution by heat drying and has no exposure and development steps.

  In addition to the relatively fine specific gravity silica fine particles (C), the printability can be further improved by using the relatively fine specific gravity heavy inorganic fine particles (E) in combination, and the followability of the substrate and the resistance It is possible to print a resist pattern which is excellent due to the warpage and the printability.

Resist Film Forming Method The resist film forming method of the present invention comprises the steps of forming a resist film of a desired pattern by performing screen printing on the surface of a substrate having a metal layer using the etching resist composition for printing of the present invention. It is a resist film formation method containing.

  The substrate having the metal layer is not particularly limited, but is preferably a resin substrate or a glass substrate such as a phenol resin, an epoxy resin, a polyamide resin, a polyimide resin, or a reinforced resin in which these resins are reinforced with glass fibers. For example, laminated substrates in which conductive metals such as copper, gold, silver, aluminum, chromium and the like are coated by lamination, vapor deposition and the like can be mentioned. The base material having such a base material or metal film may be a single layer or multiple layers. Further, the base material may be provided with a through hole or a non-through hole. Also, the shape of the substrate is not particularly limited.

  The thickness of the substrate is also not particularly limited, but the etching resist composition for printing of the present invention is excellent in printability and excellent in substrate followability even if it is a flexible substrate having a thickness of 10 to 100 μm. .

  The thickness of the resist film using the etching resist composition for printing of the present invention is preferably in the range of 1 to 100 μm, more preferably 2 to 30 μm, from the viewpoint of the balance between etching solution resistance and printability. .

  The etching resist composition for printing of the present invention can be suitably applied particularly to screen printing. In the screen printing method, it is preferable to use a fine mesh screen, particularly preferably a fine mesh screen of about 450 to 600 mesh, in order to correspond to high definition of the circuit pattern. The open area of the screen at this time is preferably about 20 to 50%.

  Types of screen plates include polyester screens, combination screens, metal screens, nylon screens and the like. Moreover, when printing the thing of a highly viscous paste state, a high tension stainless screen can be used.

  The screen printing squeegee may be round, rectangular or square, and a polishing squeegee may be used to reduce the attack angle (the angle between the plate and the squeegee at the time of printing). For the other printing conditions and the like, conventionally known conditions can be applied.

  The composition of the present invention can be dried after screen printing. Drying conditions may be appropriately determined depending on, for example, the type of the organic solvent used, but usually, for example, the drying temperature is in the range of 50 ° C. to 180 ° C., preferably 100 to 170 ° C., the drying time is 1 Minutes to 100 minutes, preferably 10 minutes to 80 minutes. A heating apparatus is not specifically limited, For example, a hot blast stove or an electric furnace etc. can be used.

Method for Producing Substrate Having Metal Layer Pattern A method for producing a substrate having a metal layer pattern includes the following steps.

(1) (Resist film formation process) Screen printing is performed using the composition using the etching resist composition for printing of the present invention on the metal layer side of a substrate having a metal layer on the surface, and a desired resist film is obtained Forming process,
(2) removing the metal layer of the portion where the resist film is not formed with an etching solution, and (3) removing the resist film using a stripping solution after the step (2). The manufacturing method of the base material which has a metal layer pattern.

  The step (1) is as described in the item of the resist film forming method.

  In the step (2) (etching step), examples of the etching solution include ferric chloride, cupric chloride, hydrofluoric acid, nitric acid, acetic acid, phosphoric acid, a mixture of these acids, an aqueous solution and the like. As an etching method, a dipping (immersion), a spray, etc. are mentioned, for example. Specifically, the method of immersing or spraying the etching liquid which made etching liquid temperature 30 to 60 degreeC for about 1 to 5 minutes is mentioned.

  In the step (3) (peeling step), an alkaline solution in which the phenol resin (A) and the acrylic resin (B) are dissolved or dispersed can be used for removing the resist film. Specifically, for example, it is easily removed by a known stripping solution such as an aqueous solution of sodium hydroxide, an aqueous solution of potassium hydroxide, an organic amine solvent and the like. The concentration of the alkali substance such as sodium hydroxide is, for example, 1 to 5% by mass.

  After formation of the resist composition film of the present invention, the substrate can be etched with high precision without peeling from the substrate during the etching process because it has excellent followability to the substrate. . In addition, the resist film after the end of etching can be easily peeled off by an aqueous alkaline solution or the like.

  Hereinafter, the present invention will be more specifically described by way of production examples, examples and comparative examples. However, the present invention is not limited by these. In each example, "parts" and "%" are by mass unless otherwise stated. Moreover, the film thickness of a coating film is based on a dry coating film.

  For microscopic observation, an optical microscope (OPTIPHOTO 300) manufactured by Nikon Corporation was used.

(Production Example 1)
In a 5-liter four-necked flask equipped with a stirrer, thermometer, and heat exchanger, 750 parts of m-cresol, 500 parts of p-cresol, 938.4 parts of 37% formalin, and 62.5 parts of triethylamine are charged. 5. Reaction (primary reaction) was performed at a reaction temperature of 68 to 72 ° C. for 4 hours. Thereafter, the mixture is neutralized (pH = 5.2) by adding 350 parts of 10% aqueous oxalic acid, and 175 parts of m-cresol, 1237.5 parts of p-cresol and 38.5 parts of oxalic acid are added. The reaction was carried out (second reaction) at pH 2.0 and a reaction temperature of 98 to 102 ° C. for 4 hours. After completion of the secondary reaction, the reaction solution was cooled to 70 ° C., 125 parts of acetone and 1250 parts of ion exchanged water were added, and the mixture was stirred and allowed to stand at about 70 ° C. After removing the separated water, washing with water was repeated again using 125 parts of acetone and 1250 parts of ion-exchanged water. Thereafter, the temperature is raised to an internal temperature of 160 ° C. under normal pressure for dehydration, and the temperature is further raised to 195 ° C. under a reduced pressure of 60 Torr to carry out dehydration / demonomerization to obtain 1,300 parts of a phenol resin (A-1). The weight average molecular weight of the obtained resin (A-1) was 11,000.

(Production Example 2)
1000 parts of phenol, 690 parts of 37% formalin and 4 parts of oxalic acid were charged into a 5-L four-necked flask equipped with a stirrer, thermometer and heat exchanger, and reflux reaction was performed for 4.5 hours at normal pressure. After completion of the reaction, the reaction solution was cooled to 70 ° C., 125 parts of acetone and 1250 parts of ion exchanged water were added, and the mixture was stirred and allowed to stand at about 70 ° C. After removing the separated water, washing with water was repeated again using 125 parts of acetone and 1250 parts of ion-exchanged water. Thereafter, the temperature was raised to an internal temperature of 160 ° C. under normal pressure for dehydration, and dehydration and demonomerization were further performed under a reduced pressure of 60 torr to 195 ° C. to obtain 910 parts of a phenol resin (A-2). The weight average molecular weight of the obtained resin (A-2) was 2,500.

(Production Example 3)
50 parts of butyl acrylate, 18 parts of styrene, 17 parts of acrylic acid, 15 parts of hydroxyethyl acrylate and t-butylperoxy-2-ethylhexanoate in a 5 L four-necked flask equipped with a stirrer, thermometer and heat exchanger A mixture of 2 parts was added dropwise over 90 hours to 90 parts of diethylene glycol monoethyl ether maintained at 120 ° C. under a nitrogen gas atmosphere.
After the addition, the mixture is aged for 1 hour, a mixture of 1 part of t-butylperoxy-2-ethylhexanoate and 10 parts of diethylene glycol monoethyl ether is added dropwise over 1 hour, and the mixture is aged for 5 hours to obtain a solid content 50 mass% acrylic resin solution (B-1) was obtained. The weight average molecular weight of the obtained resin (B-1) was 24,000, the acid value was 130 mg KOH / g, and the glass transition temperature was -18 ° C.

(Production Example 4)
In a 5-liter four-necked flask equipped with a stirrer, thermometer and heat exchanger, 20 parts of methyl methacrylate, 40 parts of butyl acrylate, 20 parts of styrene, 20 parts of methacrylic acid and t-butylperoxy-2-ethylhexanoate 2 The resulting mixture was added dropwise over 90 hours to 90 parts of diethylene glycol monoethyl ether maintained at 120 ° C. under a nitrogen gas atmosphere.
After the addition, the mixture is aged for 1 hour, a mixture of 1 part of t-butylperoxy-2-ethylhexanoate and 10 parts of diethylene glycol monoethyl ether is added dropwise over 1 hour, and the mixture is aged for 5 hours to obtain a solid content The 50 mass% acrylic resin solution (B-2) was obtained. The weight average molecular weight of the obtained resin (B-2) was 22,000, the acid value was 130 mg KOH / g, and the glass transition temperature was 30 ° C.
(Production Example 5)
In a 5-liter four-necked flask fitted with a stirrer, thermometer and heat exchanger, 20 parts of methyl methacrylate, 30 parts of butyl acrylate, 20 parts of styrene, 20 parts of methacrylic acid, 10 parts of hydroxyethyl methacrylate and t-butylperoxy-2- A mixture of 2 parts of ethyl hexanoate was added dropwise over 90 hours to 90 parts of diethylene glycol monoethyl ether maintained at 120 ° C. under a nitrogen gas atmosphere.
After the addition, the mixture is aged for 1 hour, a mixture of 1 part of t-butylperoxy-2-ethylhexanoate and 10 parts of diethylene glycol monoethyl ether is added dropwise over 1 hour, and the mixture is aged for 5 hours to obtain a solid content 50 mass% acrylic resin solution (B-3) was obtained. The weight average molecular weight of the obtained resin (B-3) was 23,000, the acid value was 130 mg KOH / g, and the glass transition temperature was 45 ° C.

(Production Example 6)
40 parts of methyl methacrylate, 10 parts of butyl acrylate, 20 parts of styrene, 20 parts of methacrylic acid in a 5 L four-necked flask equipped with a stirrer, thermometer and heat exchanger
A mixture of 10 parts of hydroxyethyl methacrylate and 2 parts of t-butylperoxy-2-ethylhexanoate is required for 3 hours in 90 parts of diethylene glycol monoethyl ether maintained at 120 ° C. under a nitrogen gas atmosphere. It dripped.
After the addition, the mixture is aged for 1 hour, a mixture of 1 part of t-butylperoxy-2-ethylhexanoate and 10 parts of diethylene glycol monoethyl ether is added dropwise over 1 hour, and the mixture is aged for 5 hours to obtain a solid content 50 mass% acrylic resin solution (B-4) was obtained. The weight average molecular weight of the obtained resin (B-4) was 24,000, the acid value was 130 mg KOH / g, and the glass transition temperature was 90 ° C.

Examples and Comparative Examples (Examples 1 to 7 and Comparative Examples 1 to 8)
Each component was mixed with a stirrer so that it might become combination composition ratio (unit: mass part) shown in Table 1, and it was etched using 3 roll mills, and etching resist composition No. 1 for printing. I got 1-15. The specific gravities of the obtained resist compositions are shown together in Table 1. The composition shown in Table 1 is based on the solid content mass of each component.

  (Note) in Table 1 means the following.

  Note 1) Acrylic resin B-5: Joncryl 67, trade name, manufactured by BASF, styrene-acrylic acid copolymer, glass transition temperature 73 ° C., acid value 213 mg KOH / g, weight average molecular weight 12,500.

Note 2) Silica fine particles: AEROSIL R812, trade name, manufactured by Nippon Aerosil Co., Ltd., average primary particle diameter 7 nm,
Note 3) Silica fine particles: Admafine SO-E1, trade name, manufactured by Admatechs Co., Ltd., average primary particle diameter 250 nm.

Note 4) Inorganic fine particles: MT-500 HD: trade name, manufactured by Tayca Corporation, titanium oxide, average primary particle diameter 50 nm, specific gravity 4.0,
Note 5) Inorganic fine particles: BARIFINE BF-20, trade name, manufactured by Sakai Chemical Industry Co., Ltd., precipitated barium sulfate, average primary particle diameter 30 nm, specific gravity 4.4.

  Note 6) Antifoamer: BYK-054, trade name, manufactured by BIC Chemie Japan, non-silicone antifoamer.

  Note 7) Color pigment: trade name, manufactured by Mitsubishi Chemical Corporation, carbon black, average primary particle diameter 20 nm.

Note 8) Organic solvent: Diethylene glycol monobutyl ether acetate (abbreviated as DGMBEA in the table), non-hydroxyl group containing organic solvent, boiling point 246.8 ° C,
Note 9) Organic solvent: Diethylene glycol monoethyl ether (abbreviated as DGMEE in the table), organic solvent containing hydroxyl group, boiling point 196 to 202 ° C., 1 hydroxyl group,
Note 10) Organic solvent: Ethylene glycol monohexyl ether (abbreviated as EGMHE in the table), boiling point 208 ° C, 1 hydroxyl group.

Note 11) Specific gravity (density) of resist composition:
The specific gravity of each resist composition was measured according to the specific gravity cup method of 4.2 of JIS-K7232 (1986).

(Examples 8 to 14 and Comparative Examples 9 to 15)
Each resist composition was subjected to the following steps (1) to (3) to produce a pattern-coated product and a substrate having a metal layer pattern. The test board obtained in each process was evaluated by the following evaluation criteria. The evaluation results are shown in Table 2. The specific test method and evaluation method will be described later.

(1) (resist film forming step);
A copper-clad laminate "UPICEL N" (trade name, Ube Industries, Ltd. flexible copper-clad laminate, copper foil thickness / polyimide film thickness = 9 μm / 25 μm) using each resist composition prepared as described above 2.) A 500 mesh screen printing plate having a line / space pattern of 100 μm / 100 μm was screen-printed in a thin line shape so as to have a dry film thickness of 20 μm. Thereafter, those dried at 120 ° C. for 10 minutes were used as test plates. The attack angle at the time of screen printing was 70 °, the squeegee speed was 200 mm / sec, and the scraper speed (speed for returning the resist composition with the squeegee) was 50 mm / sec.

(2) (etching step);
Next, the etching process which removes the unnecessary part of copper foil of the test plate obtained by process (1) was implemented on condition of the following, and the test plate after an etching was obtained.

Etching conditions: etching was performed using a spray etching apparatus under the following conditions.
・ Etchant composition
Cupric chloride (2.0 mol / L) + hydrochloric acid (1.5 mol / L)
· Spray pressure: 0.2MPa
Liquid temperature: 50 ° C
-Confirmation of etching end point: Several levels of etching were performed by changing the time, and it was confirmed with a microscope that copper did not remain between circuits, and this etching time was 1.1 times this time.

(3) (peeling process);
The resist composition was peeled off from the test plate after etching in the above step (2) under the same spray pressure as in the etching condition of 3% NaOH aqueous solution at 45 ° C. to obtain a substrate having a metal layer pattern.

(Evaluation method)
Printability:
The printing workability at the time of screen-printing each etching resist composition in the said process (1) was evaluated by the following reference | standard.
:: each resist composition can print a pattern with little sticking on the squeegee, x: each resist composition runs up on the squeegee, etc., and can not print.

Printability: The appearance of the pattern coating of the test piece obtained in the step (1) was observed with a microscope to compare the shapes.
◎: The pattern line is formed with less than 100 ± 5 μm :: The pattern line is formed with 100 ± (5 μm or more and less than 10 μm) ×: The pattern line is 100 ± 10 μm or more.

Substrate followability: A microscope observation of a film in the state which wound the test piece (polyimide film which has a dried film of the etching resist composition for each printing) obtained in the said process (1) in diameter 10mm metal cylinders And evaluated according to the following criteria.
○: no squeegee of the film, no sagging, no peeling, etc. x: s not able to follow the substrate with the resist, squeeze, sagging, sagging or the like from the film is recognized.

Spray etching impact resistance: The substrate having the pattern film of each resist composition at the end point of the step (2) was observed with a microscope and evaluated according to the following criteria.
○: no peeling of the film to the etching end point, no metal attacked ×: a film peeled off until the etching end point, and the metal was attacked.

Peelability: The substrate having each metal layer pattern obtained in the step (3) was observed with a microscope and evaluated according to the following criteria.
○: The resist composition was peeled off, and no residue of the composition remained. X: The resist composition did not peel completely, and the residue of the composition remained.

Claims (7)

(A) Phenolic resin, (B) Acrylic resin whose glass transition temperature is in the range of -30 to 50 ° C, and (C) silica particles having an average primary particle diameter of 1 to 100 nm, the specific gravity of the composition is 1 The etching resist composition for printing which is more than 0. The content of the phenolic resin (A) is 30 to 95% by mass, and the content of the acrylic resin (B) is 5 based on the total solid content of the phenolic resin (A) and the acrylic resin (B). The etching resist composition for printing according to claim 1, wherein the content of the fine particles (C) is 70% by mass and the content of the fine silica particles (C) is 1% by mass. The etching resist composition for printing according to claim 1, further comprising (D) a hydroxyl group-containing organic solvent, wherein the component (D) contains a hydroxyl group-containing organic solvent having a boiling point of 190 ° C. or higher. The etching resist composition for printing according to any one of claims 1 to 3, further comprising inorganic fine particles (E) having a specific gravity of 2.5 or more. Furthermore, the etching resist composition for printing of any one of Claims 1-4 containing a non-silicone antifoamer (F). The process of screen-printing on the surface of the base material which has a metal layer on the surface using the etching resist composition for printing of any one of Claims 1-5, and forming the resist film of a desired pattern is included. Resist film formation method. (1) On the metal layer side of a substrate having a metal layer on the surface, screen printing is performed using the etching resist composition for printing according to any one of claims 1 to 5 to form a desired resist film The process to
(2) removing the metal layer in a portion where the resist film is not formed with an etching solution, and (3) removing the resist film using a stripping solution after the step (2). The manufacturing method of the base material which has a layer pattern.