JP2004260143A - Resist composition for printing ink, method for forming resist film, and method for manufacturing substrate using method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resist composition for printing ink, a method for forming a resist film, and a method for manufacturing a substrate, wherein the process is simplified, the process control is facilitated, and delicate patterns can be formed. <P>SOLUTION: A resist composition for printing ink comprises a phenolic resin as the principal resin component, and furthermore, contains a thickening agent. As the resist composition for printing ink comprising the phenolic resin as the principal resin, a composition which has been conventionally used can be used especially without restriction. More specifically, e.g., the composition (resist composition based on organic solvent), obtained by dissolving or dispersing the phenolic resin in an organic solvent, can be used. For example, a novolak resin and/or a polyvinylphenol resin are preferably used as the phenolic resin. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a novel resist composition for printing ink, a method for forming a resist film thereof, and a method for producing a substrate using the same.

  In recent years, printing inks have been widely used in various fields. Among the printing inks, a resist composition for a printing ink has been developed as one of ink resist materials having a special function in flexo technology.

  Such a printing ink resist composition is prepared by, for example, applying a negative-type energy-sensitive radiation-sensitive resist composition which is cured by an active energy ray to a metal substrate surface such as a copper-clad laminate substrate, and then obtaining a desired printing pattern. Using a print mask or directly irradiating active energy rays, remove the uncured film by a development process, and remove the exposed metal layer portion with an etchant to form a desired pattern, that is, a negative type A pattern forming method is known (see Patent Document 1).

  In recent years, in addition to the above, in addition to the above, a positive-type energy-sensitive radiation-sensitive resist composition that decomposes by active energy rays is applied, and then irradiated with active energy rays, and the irradiated portion is removed with a developer to remove exposed metal. There is known a method of forming a desired pattern by removing a layer portion with an etchant, that is, a pattern forming method using a positive type (see Patent Document 2).

  However, in the above-mentioned negative and positive type active energy ray pattern forming methods, facilities and ancillary facilities for irradiating active energy rays are required, the number of steps by active energy ray irradiation increases, and process management is increased. There is a problem that it is troublesome.

Conventionally, as a general printing ink, one using a rosin-modified phenol resin, a rosin ester resin, a maleic acid resin, a petroleum resin, an alkyd resin, or the like as a resin varnish is known. However, these printing inks are inks used in offset printing and the like, and even when such a printing ink is used as a resist composition, the printed film is completely peeled off or partially peeled off by etching. Therefore, a delicate pattern is not formed.
JP-A-2000-63451 JP 2001-22067 A

  An object of the present invention is to provide a resist composition for printing ink, a method for forming a resist film, and a method for manufacturing a substrate using the same, which are simple in process, easy in process control, and capable of forming a delicate pattern. It is in.

  The present inventors have conducted intensive studies to achieve the above object, and as a result, when a thickener is further added to a resist composition for printing ink containing a phenolic resin as a main resin component, a conventional problem is solved. They have found that all can be solved, and have completed the present invention.

  That is, the present invention is a resist composition for printing ink, which comprises a phenol resin as a main resin component and further contains a thickener.

  Furthermore, the present invention provides screen printing on a surface of a substrate having a metal layer on a surface thereof, using a resist composition for a printing ink containing a phenol resin as a main resin component and further containing a thickener, to obtain a resist having a desired pattern. This is a method for forming a resist film having a step of forming a film.

The present invention further provides (1) screen printing on a surface of a substrate having a metal layer on the surface using a resist composition for a printing ink containing a phenol resin as a main resin component and further containing a thickener. Forming a resist film of a pattern,
(2) a step of developing and removing the metal layer in a portion where the resist film is not formed by using an etchant;
(3) A method of manufacturing a substrate having a metal layer pattern, comprising a step of removing a resist film after the step (2).

  First, the resist composition of the present invention will be described below.

  The resist composition of the present invention is characterized by comprising a phenol resin as a main resin component and further containing a thickener.

  As the resist composition for a printing ink containing a phenol resin as a main resin component, those conventionally used as a printing ink can be used without any particular limitation. Specifically, for example, a composition in which a phenol resin is dissolved or dispersed in an organic solvent (organic solvent-based resist composition) can be used.

  As the phenol resin, for example, a novolak resin or a polyvinyl phenol resin is preferably used.

  Novolak resins include, for example, phenol, m-cresol, o-cresol, p-cresol, 2,5-xylenol, 3,5-xylenol, resorcinol, pyrogallol, bisphenol, bisphenol-A, trisphenol, o-ethylphenol , M-ethyl phenol, p-ethyl phenol, propyl phenol, n-butyl phenol, t-butyl phenol, 1-naphthol, at least one of aromatic hydrocarbons such as 2-naphthol, under acidic catalyst, formaldehyde, acetaldehyde, Polycondensation with aldehydes such as propionaldehyde, benzaldehyde and furfural and at least one aldehyde or ketone selected from ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone What it was, and the like. Instead of formaldehyde and acetaldehyde, paraformaldehyde and paraaldehyde, respectively, may be used.

  The polystyrene estimated weight average molecular weight by gel permeation chromatography (hereinafter abbreviated as “GPC”) measurement of the novolak resin (hereinafter, the weight average molecular weight by GPC measurement is abbreviated as “Mw”) is preferably 300 to 300,000. And particularly preferably from 500 to 200,000. The lower limit of each of these ranges is significant in terms of etching resistance, and the upper limit is significant in terms of the solubility of the resist film after etching in an alkali stripper.

  As the aromatic hydrocarbons of the novolak resin, phenol, o-cresol, m-cresol, p-cresol, 2,5-xylenol, 3,5-xylenol, and resorcin are more preferable among those described above. It is preferable to use a novolak resin obtained by polycondensing at least one of these phenols with at least one selected from aldehydes such as formaldehyde, acetaldehyde, and propionaldehyde. Among the aldehydes, formaldehyde is particularly preferred.

Examples of the polyvinyl phenol resin include o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (o-hydroxyphenyl) propylene, 2- (m-hydroxyphenyl) propylene, and 2- (p-hydroxyphenyl). ) One or more polymers of hydroxystyrenes such as propylene. Hydroxystyrenes are chlorine in the aromatic ring, bromine, iodine, may have a substituent such as an alkyl substituent of halogen or C ₁ -C _4, such as fluorine. Accordingly, the polyvinyl phenol resin, may have an alkyl substituent of halogen or C ₁ -C ₄ the aromatic ring. However, an unsubstituted polyvinyl phenol resin is preferred.

  The polyvinyl phenol resin is usually obtained by polymerizing one or more hydroxystyrenes which may have a substituent in the presence of a radical polymerization initiator or a cationic polymerization initiator. This polyvinyl phenol resin may be partially hydrogenated. Further, a resin in which some OH groups of polyvinylphenols are protected by a t-butoxycarbonyl group, a pyranyl group, a furanyl group, or the like may be used.

  Mw of the polyvinyl phenol resin is preferably from 1,000 to 100,000, particularly preferably from 1,500 to 50,000. The lower limit of each of these ranges is significant in terms of etching resistance, and the upper limit is significant in terms of the solubility of the resist film after etching in an alkali stripper.

  The novolak resins and polyvinylphenol resins described above are available as commercial products. Examples of the product name include MER-7966, MER-7969, MER-7971, MER7980 (all manufactured by Meiwa Kasei Co., Ltd.), PR-HF-3, PR-50731 (all manufactured by Sumitomo Bakelite Co., Ltd.), and the like. Is mentioned.

  In the present invention, when a composition in which a phenol resin is dissolved or dispersed in an organic solvent is used, the organic solvent is not particularly limited as long as the solvent can dissolve or disperse the phenol resin, and a conventionally known organic solvent is used. it can. Specific examples of the organic solvent include hydrocarbon solvents such as hexane, heptane, octane, toluene, xylene, dichloromethane, chloroform, carbon tetrachloride, and trichloroethylene; alcohol solvents such as methanol, ethanol, propanol and butanol; diethyl ether; Ether solvents such as dipropyl ether, dibutyl ether, ethyl vinyl ether, dioxane, propylene oxide, tetrahydrofuran, cellosolve, methyl cellosolve, butyl cellosolve, methyl carbitol, diethylene glycol monoethyl ether; acetone, methyl ethyl ketone, methyl isobutyl ketone, isophorone, Ketone solvents such as cyclohexanone; ester solvents such as methyl acetate, ethyl acetate, propyl acetate, and butyl acetate; pyridine, form Bromide, N, other solvents such as N- dimethylformamide; and the like.

  In the present invention, a thickener is further added to the composition containing the phenol resin described above as a main resin component. Specifically, it is preferable to use inorganic fine particles or wax as the thickener.

  The average particle diameter of the inorganic fine particles is preferably from 3 nm to 10 μm, more preferably from 5 nm to 8 μm. The lower limit of each of the above ranges is significant in that the viscosity of the composition is kept low so that unpainted portions are not formed, and the printing workability is improved. The upper limit of each of the above ranges is significant in that the smoothness and linearity of the pattern surface and side surfaces are improved and a delicate pattern is obtained.

  The shape of the inorganic fine particles may be any of a spherical shape, a scale shape, a plate shape, and an amorphous shape. In particular, a scale shape and a spherical shape capable of imparting viscosity, which will be described in detail later, are preferable.

  The inorganic fine particles are commercially available. Preferred inorganic fine particles are listed below. Silosphere C-1504 (average particle diameter 4.5 μm) (manufactured by Fuji Silysia Chemical Ltd.) as spherical fine powder silica, and Admafine SO-25R (average particle diameter 800 nm) as spherical silicon oxide (Co., Ltd.) Aeromatil 200 (average particle diameter 12 nm), Aerosil 380 (average particle diameter 7 nm), Aerosil R805 (average particle diameter 12 nm), Aerosil R812 (average particle diameter 7 nm) (all manufactured by Nippon Aerosil Co., Ltd.), Examples of the spherical acrylic fine particles include Ganz Pearl GM-0401S (average particle size: 4 μm), spherical PBMA-based crosslinked fine particles Ganz Pearl GB-05S (average particle size: 5 μm) (all manufactured by Ganz Kasei Co., Ltd.), and spherical resin fine particle Trefill E -500 (average particle size 3 μm) (manufactured by Dow Corning Toray Silicone Co., Ltd.) Barium sulfate BF-10P (average particle diameter 60 nm), barium sulfate BF-20P (average particle diameter 30 nm), barium sulfate BF-20F (average particle diameter 30 nm) (all manufactured by Sakai Chemical Industry Co., Ltd.), flaky micromica MK-100 (average particle diameter 3 to 5 μm), organically treated mica Somasif ME-100 (average particle diameter 5 to 7 μm) (all manufactured by Corp Chemical Co., Ltd.) and the like.

  As the wax, for example, an amide compound having 12 to 44 carbon atoms and a bisamide compound having 12 to 44 carbon atoms are preferable.

  Specific examples of the amide compound having 12 to 44 carbon atoms include, for example, lauric amide, palmitic amide, stearic amide, behenic amide, hydroxystearic amide, erucic amide, ricinoleic amide, N-stearyl Examples include stearic acid amide, N-oleyl oleic acid amide, N-stearic acid oleic acid amide, N-stearyl erucic acid amide, N-oleyl palmitic acid amide, methylol stearic acid amide, and the like.

  Specific examples of the bisamide compound having 12 to 44 carbon atoms include, for example, methylenebisstearic acid amide, ethylenebisstearic acid amide, ethylenebisbehenic acid amide, hexamethylenebisstearic acid amide, hexamethylenebisbehenic acid amide, N, N'-distearyl adipamide, N, N'-distearyl sebacamide, N, N'-methylenebisoctadecanamide, ethylenebisoleamide, hexamethylenebisoleamide, N, N'- Examples thereof include dioleyl adipamide, N, N'-dioleyl sebacamide, m-xylylene bisstearic acid amide, and N, N'-distearyl isophthalic acid amide.

  Such waxes are commercially available. Examples of trade names include Disparon 6840-10X (fatty acid amide wax), Disparon 6900-20X (fatty acid amide wax), Disparon A650-20X (fatty acid amide wax) (all manufactured by Kusumoto Kasei Co., Ltd.).

  The compounding ratio of the thickener is preferably from 10 to 500 parts by weight, more preferably from 20 to 300 parts by weight, based on 100 parts by weight of the resin solids. The lower limit of each of the above ranges is significant in improving printing workability by obtaining a desired viscosity or viscosity. The upper limit of each of the above ranges is significant in improving the etching resistance by ensuring a sufficient amount of resin in the resist film.

  Conventionally known additives can be added to the resist composition for printing ink, if necessary. Specific examples include a dye, a pigment, a filler other than the above, an antioxidant, an anti-cissing agent, a resin, a plasticizer, and an adhesive other than the above.

  The solid content of the resist composition for printing ink is preferably from 20 to 90% by weight, more preferably from 30 to 70% by weight. The lower limit of each of the above ranges is significant in that the amount of solvent is suppressed to prevent exudation of the resist film. The upper limit of each of the above ranges is significant in that the drying speed of the resist solution is appropriately suppressed, the plate is prevented from drying too quickly, and the printing workability is improved.

  The viscosity of the resist composition for printing ink measured with a rotational viscometer (6 rpm, measuring temperature 25 ° C.) is preferably 1 Pa · s to 300 Pa · s, more preferably 2 Pa · s to 200 Pa · s. The lower limit of each of the above ranges is significant in suppressing the flow of the printed resist pattern and improving the pattern accuracy. The upper limit of each of the above ranges is significant in that fluidity is imparted to the resist solution so that a sufficient resist solution is applied onto the substrate.

  The viscosity of the resist composition for printing ink is preferably 1.0 or more, more preferably 1.1 to 10.0. The lower limit of each of the above ranges is significant in that the viscosity of the resist liquid during printing is appropriately reduced and a sufficient resist liquid is applied onto the substrate.

  Specifically, the viscosity is a structural viscosity index R defined by the following equation (1).

R = Va / Vb (1)
(However, in the formula (1), Va is an apparent viscosity (mPa · sec) measured at a rotation speed of 6 times / minute by an MR300 rheometer (trade name, manufactured by Rheology Co., Ltd.) at a temperature of 20 ° C. And Vb is the viscosity (mPa · sec) similarly measured at a rotation speed of 60 times / minute).

  The resist composition for a printing ink of the present invention can be applied to any type of printing plate such as letterpress, gravure, and screen. In particular, it is preferably used in screen printing.

  The method of forming a resist film of the present invention includes a step of performing screen printing on the surface of a substrate having a metal layer on the surface using the resist composition for a printing ink of the present invention to form a resist film having a desired pattern. Features.

  As a substrate having a metal layer on the surface, preferably a phenolic resin, an epoxy resin, a polyamide resin or a resin surface substrate such as a reinforced resin reinforced with glass fiber or a glass substrate, for example, copper, gold, silver, A laminated substrate coated with a conductive metal such as aluminum or chromium by lamination, vapor deposition, or the like is given. These substrates and metal films may be composed of a single layer or multiple layers. Further, the substrate may be provided with a through-hole or a non-through-hole.

  It is preferable that the viscosity, solid content, viscosity and the like of the resist composition to be printed satisfy the above-described conditions.

  After screen printing, the printed resist composition is dried as necessary. The drying conditions may be appropriately determined depending on, for example, the type of the organic solvent used, and are usually 1 minute to 30 minutes at 20 ° C. In the case of drying at a temperature of about 80 ° C., it may be about 10 seconds to 10 minutes.

  The method for manufacturing a substrate having a metal layer pattern according to the present invention includes the following steps.

(1) Screen printing is performed on the surface of a substrate having a metal layer on the surface using a resist composition for a printing ink containing a phenol resin as a main resin component and further containing a thickener to form a resist film having a desired pattern. Forming,
(2) a step of developing and removing the metal layer in a portion where the resist film is not formed by using an etchant;
(3) A step of removing the resist film after the step (2).

  Step (1) is as described above.

  In the step (2), examples of the etchant include an aqueous solution of ferric chloride, cupric chloride, and a mixed acid of nitric acid, acetic acid, and phosphoric acid. Examples of the etching method include a method of performing the etching at 40 ° C. for about 5 minutes by dipping or spraying.

  In the step (3), for removing the resist film, for example, a solvent that dissolves or disperses the phenol resin can be used.

  In the present invention, the following remarkable effects can be obtained.

  (A) The phenol resin used as the resist resin component has excellent solubility in an organic solvent, so that a viscosity or viscosity suitable for a printing resist composition can be obtained.

  (B) Since the phenol resin film after the organic solvent is volatilized is excellent in chemical resistance to an etching solution, a delicate pattern can be formed.

  (C) By combining a phenolic resin and a thickener, a viscosity and viscosity suitable for a printing resist composition can be obtained.

  (D) Thickeners such as inorganic fine particles and wax are excellent in chemical resistance to an etching solution, so that a delicate pattern can be formed.

  Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited to these Examples. In Examples and Comparative Examples, “parts” and “%” indicate “parts by weight” and “% by weight”, respectively.

<Production of phenol resin used in Examples 1 to 4 and Comparative Example 1>
In a 5 L four-necked flask equipped with a stirrer, a thermometer and a heat exchanger, 750 parts of m-cresol, 500 parts of p-cresol (P1 = 1250 parts), 938.4 parts of 37% formalin (A) (molar ratio) (A / P1 = 1.0) and 62.5 parts of triethylamine were charged and reacted at pH 8.5 at a reaction temperature of 68 to 72 ° C. for 4 hours (primary reaction). At the end of the primary reaction, the content of three or more nuclei was 55%. Thereafter, 350 parts of 10% aqueous oxalic acid was added for neutralization (pH = 5.2), and 175 parts of m-cresol and 1237.5 parts of p-cresol (P2 = 1412.5 parts; molar ratio A / (P1 + P2) = 0.47, P1 / P2 = 0.88) and 38.5 parts of oxalic acid were added, and the mixture was reacted (secondary reaction) at pH 2.0 and a reaction temperature of 98 to 102 ° C. for 4 hours. After the completion of the secondary reaction, the mixture was cooled to 70 ° C., 125 parts of acetone and 1250 parts of ion-exchanged water were added, and the mixture was stirred and left at about 70 ° C. After removing the separated water, a water washing operation was performed again using 125 parts of acetone and 1250 parts of ion-exchanged water. Thereafter, the mixture was dehydrated under normal pressure to an internal temperature of 160 ° C., and further dehydrated and demonomerized to 195 ° C. under a reduced pressure of 60 torr to obtain 1300 parts of a phenol resin. The weight average molecular weight of the obtained resin was 11,000.

<Production of acrylic resin used in Comparative Example 2>
A mixture of 40 parts of methyl methacrylate, 40 parts of butyl acrylate, 15 parts of styrene, 5 parts of acrylic acid and 2 parts of azobisisobutyronitrile in 90 parts of propylene glycol monomethyl ether kept at 110 ° C. under a nitrogen gas atmosphere. Was added dropwise over 3 hours. After the dropwise addition, the mixture was aged for 1 hour, and a mixed solution composed of 1 part of azobisdimethylvaleronitrile and 10 parts of propylene glycol monomethyl ether was added dropwise for 1 hour, and aged for 5 hours to obtain an acrylic resin solution.

<Example 1>
The phenol resin produced as described above is dissolved in cyclohexanone so that the solid content becomes 50%, and spherical silicon oxide (fine silica, manufactured by Nippon Aerosil Co., Ltd., trade name Aerosil R812, average particle size) is used as a thickener. (Diameter: 7 nm) was added to 100 parts of the resin solids in an amount of 50 parts, and the mixture was dispersed with a three-roll mill to obtain a screen printing resist solution.

  This liquid was screen-printed on a 500 mesh to form a line / space = 100/100 μm pattern on a copper substrate deposited on glass, and heated on a hot plate at 100 ° C. for 30 minutes. Thereafter, etching was performed by immersion in a 4% aqueous ferric chloride solution.

<Examples 2 to 4, Comparative Examples 1 and 2>
A resist solution was prepared and etched in the same manner as in Example 1 except that the composition shown in Table 1 was employed.

  The test results of Examples and Comparative Examples are shown in Table 1 below.

増粘剤ａ：球状酸化ケイ素（日本アエロジル株式会社製、商品名アエロジルＲ８１２、平均粒子径７ｎｍ）
増粘剤ｂ：脂肪酸アマイドワックス（楠本化成株式会社製、商品名ディスパロン６９００）
増粘剤ｃ：硫酸バリウム（堺化学工業株式会社製、商品名硫酸バリウムＢＦ−２０Ｐ、平均粒子径３０ｎｍ）／脂肪酸アマイドワックス（楠本化成株式会社製、商品名ディスパロン６９００）
粘度：B型粘度計 ６rpm at２５℃
パターン形成：「○」はラインが１００±５μｍで形成できているもの、「×」はラインが１００±５μｍで形成できていないいもの。
エッチング耐性：「○」はレジスト膜剥がれがないもの、「×」はレジスト膜剥がれたもの。

Thickener a: spherical silicon oxide (manufactured by Nippon Aerosil Co., Ltd., trade name Aerosil R812, average particle diameter 7 nm)
Thickener b: fatty acid amide wax (Kusumoto Kasei Co., Ltd., trade name: Dispalon 6900)
Thickener c: barium sulfate (manufactured by Sakai Chemical Industry Co., Ltd., trade name barium sulfate BF-20P, average particle diameter 30 nm) / fatty acid amide wax (manufactured by Kusumoto Chemicals, trade name Disparon 6900)
Viscosity: B-type viscometer 6 rpm at 25 ° C
Pattern formation: “○” indicates that the line was formed at 100 ± 5 μm, and “×” indicates that the line was not formed at 100 ± 5 μm.
Etching resistance: "O" indicates that the resist film did not peel off, and "X" indicates that the resist film peeled off.

Claims (10)

  A resist composition for printing ink comprising a phenolic resin as a main resin component and further containing a thickener.   The resist composition for a printing ink according to claim 1, wherein the phenol resin is one or both of a novolak resin and a polyvinyl phenol resin.   The resist composition for a printing ink according to claim 1, wherein the thickener is an inorganic fine particle having a particle diameter of 3 nm to 10 µm.   The resist composition for a printing ink according to claim 1, wherein the thickener is a wax.   The resist composition for a printing ink according to claim 1, wherein the content of the thickener is 10 parts by weight to 500 parts by weight based on 100 parts by weight of the resin solid content.   The resist composition for a printing ink according to claim 1, which is an organic solvent-based resist composition.   The printing ink resist composition according to claim 1, wherein the viscosity measured by a rotational viscometer (6 rpm, measurement temperature: 25 ° C) is 1 Pa · s to 300 Pa · s.   The resist composition for a printing ink according to claim 1, which is a resist composition for a screen printing ink.   Forming a resist film of a desired pattern on the surface of a substrate having a metal layer on the surface by using a resist composition for a printing ink comprising a phenol resin as a main resin component and further containing a thickener. A method for forming a resist film comprising: (1) Screen printing is performed on the surface of a substrate having a metal layer on the surface using a resist composition for a printing ink containing a phenol resin as a main resin component and further containing a thickener to form a resist film having a desired pattern. Forming,
(2) a step of developing and removing the metal layer in a portion where the resist film is not formed by using an etchant;
(3) A method for manufacturing a substrate having a metal layer pattern, comprising a step of removing a resist film after the step (2).