Peeling method

Abstract

To provide a peeling method which can peel a patterned resin layer from a base material without corroding the base material after sandblast treatment, and without generating cracks even when a thickness of the base material subjected to the sandblast treatment is thin.SOLUTION: There is provided a peeling method for peeling a patterned resin layer from a base material using a peeling liquid after sandblast treatment, wherein the patterned resin layer is a layer formed of a photosensitive resin composition containing at least (A) urethane acrylate, (B) a photopolymerization initiator, and (C) an alkali-soluble resin, and the peeling liquid contains at least 3-methoxy-N,N-dimethylpropanamide and / or 3-butoxy-N,N-dimethylpropanamide.SELECTED DRAWING: None

Description

[[Technical Field]]

[0001] The present invention relates to a peeling method for peeling a resin layer patterned by a peeling solution from a substrate after sandblasting treatment. [[Background Art]]

[0002] Conventionally, when cutting glass, stone, metal, plastic, ceramic or the like to form a relief, processing by sandblasting has been performed. In this processing, a sandblasting treatment is performed in which a resin layer patterned by a photolithography method or the like as a mask material is provided on a substrate, and then an abrasive is sprayed to selectively cut non-mask portions.

[0003] As a photosensitive resin composition used as a mask material for sandblasting treatment, for example, a negative photosensitive resin composition containing an alkali-soluble resin, a urethane (meth)acrylate compound and a photopolymerization initiator is generally used. As the alkali-soluble resin, cellulose derivatives or carboxy group-containing acrylic resins are used (see, for example, Patent Documents 1 to 3).

[0004] After sandblasting, a process called resist stripping is performed to remove the patterned resin layer from the substrate. Methods for resist stripping include immersion in a chemical solution (dip method) and physical removal using high-pressure water washing. Examples of chemical solutions used to strip the resin layer include a strongly alkaline chemical solution containing monoethanolamine (e.g., Patent Document 4) and a stripping solution containing monoethanolamine and tetramethylammonium hydroxide (Patent Document 5). However, if the substrate to be sandblasted is made of a material that corrodes with alkaline chemical solutions, such as aluminum nitride or alumina, then such a strongly alkaline chemical solution cannot be applied. In such cases, a method is used in which the resin layer is swollen and stripped by immersion in a solvent such as acetone or ethyl acetate. However, if the surface of the patterned resin layer is covered with blasting powder or damaged by the sandblasting process, the resin layer may not swell sufficiently, making resist stripping difficult.

[0005] Therefore, a method of physically removing the resist after sandblasting has been applied using high-pressure water washing. However, when the substrate to be sandblasted is thin, the water pressure during high-pressure washing can cause cracks in the substrate itself. Also, if the adhesion between the substrate and the patterned resin layer is designed to be strong, physical removal becomes difficult, so there has been a need for a simpler method of removing the resist after sandblasting. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 3449572 [Patent Document 2] Patent No. 3846958 [Patent Document 3] Japanese Patent Application Publication No. 10-69851 [Patent Document 4] Japanese Patent Publication No. 2004-12783 [Patent Document 5] Japanese Patent Publication No. 2001-109167 [Overview of the project] [Problems that the invention aims to solve]

[0007] The object of the present invention is to provide a method for peeling off a resin layer from a substrate after sandblasting, even if the resin layer has high adhesion to the substrate, without corroding the substrate, and without cracking even if the substrate is thin when sandblasting is performed. [Means for solving the problem]

[0008] The above problems were solved by the following means.

[0009] A method for peeling a patterned resin layer from a substrate using a peeling solution after sandblasting, wherein the patterned resin layer is formed from a photosensitive resin composition containing at least (A) urethane acrylate, (B) a photopolymerization initiator, and (C) an alkali-soluble resin, and the peeling solution contains at least 3-methoxy-N,N-dimethylpropanamide and / or 3-butoxy-N,N-dimethylpropanamide. [Effects of the Invention]

[0010] The present invention provides a peeling method that allows a resin layer with high adhesion to the substrate to be peeled off from the substrate after sandblasting without corroding the substrate, and without cracking even when the substrate is thin. [Modes for carrying out the invention]

[0011] The present invention will be described in detail below.

[0012] (A) Urethane acrylates relating to the present invention include reaction products of a compound having terminal isocyanate groups obtained by reacting (a) a compound having a polyvalent hydroxyl group with (b) a polyvalent isocyanate compound with (c) a (meth)acrylate compound having a hydroxyl group.

[0013] (a) Examples of compounds having polyvalent hydroxyl groups include polyesters and polyethers having polyvalent hydroxyl groups.

[0014] Polyesters having polyvalent hydroxyl groups include polyesters obtained by ring-opening polymerization of lactones, polycarbonates, and polyesters obtained by condensation reactions of alkylene glycols such as ethylene glycol, propylene glycol, tetramethylene glycol, diethylene glycol, triethylene glycol, and dipropylene glycol with dicarboxylic acids such as maleic acid, fumaric acid, glutaric acid, and adipic acid. Specific examples of lactones include δ-valerolactone, ε-caprolactone, β-propiolactone, α-methyl-β-propiolactone, β-methyl-β-propiolactone, α,α-dimethyl-β-propiolactone, and β,β-dimethyl-β-propiolactone. Specific examples of polycarbonates include reaction products of diols such as bisphenol A, hydroquinone, and dihydroxycyclohexanone with carbonyl compounds such as diphenyl carbonate, phosgene, and succinic anhydride.

[0015] Furthermore, specific examples of polyethers having polyvalent hydroxyl groups include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, and polypentamethylene ether glycol. In particular, (a) it is preferable that the compound having polyvalent hydroxyl groups is tetramethylene glycol or polytetramethylene ether glycol, as this further improves sandblasting resistance and resolution.

[0016] (b) Examples of polyvalent isocyanate compounds include aliphatic or alicyclic diisocyanate compounds such as dimethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, 2,2-dimethylpentane-1,5-diisocyanate, octamethylene diisocyanate, 2,5-dimethylhexane-1,6-diisocyanate, 2,2,4-trimethylpentane-1,5-diisocyanate, nonamethylene diisocyanate, 2,2,4-trimethylhexane diisocyanate, decamethylene diisocyanate, and isophorone diisocyanate, and these compounds can be used individually or as mixtures of two or more.

[0017] (c)Specific examples of (meth)acrylate compounds having a hydroxyl group include hydroxymethyl acrylate, hydroxymethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, and compounds obtained by adding 1 to 10 moles of ε-caprolactone to 1 mole of any of these. In particular, it is preferable that the (meth)acrylate compound having a hydroxyl group is 4-hydroxybutyl acrylate, as this further improves sandblasting resistance and resolution.

[0018] The (A) urethane acrylate according to the present invention may contain a carboxyl group. The presence of a carboxyl group tends to improve solubility in developing solutions. The (A) urethane acrylate containing a carboxyl group can be obtained by first reacting a diisocyanate compound with a diol compound having a carboxyl group such that isocyanate groups remain at both ends, and then reacting the terminal isocyanate groups of this reactant with a (meth)acrylate compound having a hydroxyl group.

[0019] As the (A) urethane acrylate related to the present invention, commercially available products can also be preferably used, for example, KAYARAD® UXF-4001-M35 (manufactured by Nippon Kayaku Co., Ltd.), Shiko® UV-2000B (manufactured by Mitsubishi Chemical Corporation), Shiko UV-3000B (manufactured by Mitsubishi Chemical Corporation), EBECRYL® 210 (manufactured by Daicel Ornex Co., Ltd.), KRM8296 (manufactured by Daicel Ornex Co., Ltd.), etc.

[0020] The photopolymerization initiators for component (B) include benzophenone, N,N,N′,N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), N,N,N′,N′-tetraethyl-4,4′-diaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propano Aromatic ketones such as n-1; 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthaquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethyl Quinones such as ruanthraquinone; benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; benzoin compounds such as benzoin, methylbenzoin, and ethylbenzoin; benzyl derivatives such as benzyldimethyl ketal; 2,4,5-triarylimidazole dimers such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, and 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer; acridine derivatives such as 9-phenylacridine and 1,7-bis(9,9′-acridinyl)heptane; N-phenylglycine, N-phenylglycine derivatives, and coumarin compounds are examples. In the above 2,4,5-triarylimidazole dimer, the substituents on the aryl groups of the two 2,4,5-triarylimidazoles may be identical and symmetric, or they may be different and asymmetric. Furthermore, a thioxanthone compound may be combined with a tertiary amine compound, such as the combination of diethylthioxanthone and dimethylaminobenzoic acid.These may be used alone or in combination of two or more kinds. Among these, the use of 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer alone or in combination with another photopolymerization initiator is preferable because a highly sensitive photosensitive resin composition can be obtained.

[0021] Examples of the alkali-soluble resin as component (C) include alkali-soluble cellulose derivatives, carboxy group-containing acrylic resins, and the like. A photosensitive resin composition containing a carboxy group-containing acrylic resin has high adhesion to a substrate and tends to make resist stripping difficult after sandblasting, and therefore can be advantageously used in the stripping method of the present invention.

[0022] Examples of the alkali-soluble cellulose derivative include cellulose acetate phthalate, hydroxypropyl methylcellulose phthalate, hydroxypropyl methylcellulose acetate phthalate, hydroxypropyl methylcellulose acetate succinate, and the like.

[0023] Examples of the carboxy group-containing acrylic resin include acrylic polymers obtained by using (meth)acrylate as a main component and copolymerizing the same with an ethylenically unsaturated carboxylic acid. Additionally, other copolymerizable monomers having an ethylenically unsaturated group may be copolymerized.

[0024] Examples of (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-(dimethylamino)ethyl (meth)acrylate, 2-(diethylamino)ethyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, and 2,2,3,3-tetrafluoropropyl (meth)acrylate.

[0025] As ethylenically unsaturated carboxylic acids, monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid are preferably used, and dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid, as well as their anhydrides and half-esters, can also be used. Among these, acrylic acid and methacrylic acid are particularly preferred.

[0026] Other copolymerizable monomers having ethylenically unsaturated groups include, for example, styrene, α-methylstyrene, p-methylstyrene, p-ethylstyrene, p-methoxystyrene, p-ethoxystyrene, p-chlorostyrene, p-bromostyrene, (meth)acrylonitrile, (meth)acrylamide, diacetone acrylamide, vinyltoluene, vinyl acetate, vinyl-n-butyl ether, and the like.

[0027] The acid value (JIS-K0070:1992) of alkali-soluble resins is preferably 30 to 500 mg KOH / g, and more preferably 100 to 300 mg KOH / g. If the acid value is less than 30 mg KOH / g, the alkali development time tends to be longer, while if it exceeds 500 mg KOH / g, the sandblasting resistance may decrease.

[0028] Furthermore, the mass-average molecular weight of the alkali-soluble resin is preferably 10,000 to 200,000, and more preferably 10,000 to 150,000. If the mass-average molecular weight of the alkali-soluble resin is less than 10,000, it may be difficult to form a photosensitive resin layer from the photosensitive resin composition, while if it exceeds 200,000, the solubility in alkaline developer tends to deteriorate.

[0029] In the photosensitive resin composition according to the present invention, the amount of component (A) is preferably 30 to 80% by mass, and more preferably 50 to 70% by mass, relative to the total amount of components (A), (B), and (C). If the amount of component (A) is less than 30% by mass, sandblast resistance tends to decrease and photosensitivity tends to be insufficient. On the other hand, if it exceeds 80% by mass, the tackiness of the film surface tends to increase.

[0030] The amount of component (B) is preferably 0.1 to 10% by mass, and more preferably 0.3 to 6.5% by mass, relative to the total amount of components (A), (B), and (C). If the amount of component (B) is less than 0.1% by mass, the photopolymerization tends to be insufficient. On the other hand, if it exceeds 10% by mass, the absorption of active light on the surface of the photosensitive resin layer increases during exposure, and photocrosslinking inside the photosensitive resin layer tends to be insufficient.

[0031] The amount of component (C) is preferably 3 to 50% by mass, and more preferably 20 to 40% by mass, relative to the total amount of components (A), (B), and (C). If the amount of component (C) is less than 3% by mass, the film-forming properties may be insufficient, or the alkali-developability may decrease. If the amount of component (C) exceeds 50% by mass, the sandblasting resistance may decrease.

[0032] Furthermore, the photosensitive resin composition according to the present invention may contain components other than the above components (A) to (C) as needed. Examples of such components include crosslinkable monomers, sensitizers, thermal polymerization inhibitors, plasticizers, colorants (dyes, pigments), photochromicants, thermal color inhibitors, defoamers, flame retardants, stabilizers, adhesion promoters, leveling agents, peel accelerators, antioxidants, fragrances, thermosetting agents, water repellents, and oil repellents, and each can be contained in an amount of approximately 0.01 to 20% by mass relative to the total amount of components (A) to (C). These components can be used individually or in combination of two or more types.

[0033] The thickness of the photosensitive resin layer formed from the above-described photosensitive resin composition is preferably 10 to 150 μm, and more preferably 20 to 120 μm. If the thickness of the photosensitive resin layer is too large, problems such as a decrease in resolution and increased cost are likely to occur. Conversely, if it is too thin, sandblasting resistance tends to decrease.

[0034] Examples of substrates related to the present invention include glass, stone, metal, plastic, and ceramic. Examples of substrates that corrode in an alkaline aqueous solution include aluminum nitride and alumina, and the stripping method of the present invention can be usefully used for these materials.

[0035] A common method for forming a patterned resin layer as a mask material on a substrate is photolithography. First, a photosensitive resin composition containing at least the components (A) to (C) described above is applied to a support such as a polyethylene terephthalate (PET) film and dried to obtain a laminate having a photosensitive resin layer. Next, the surface of the photosensitive resin layer of the laminate is attached to the substrate using a laminator or the like. Then, the photosensitive resin layer is exposed to ultraviolet light through a desired pattern, and the support is peeled off. Alternatively, if resolution is required, the support is peeled off and then exposed to ultraviolet light. In this case, the exposed portion of the photosensitive resin layer is cured by polymerization. Next, the unexposed portion is washed with a developer solution, and then washed with water to form a patterned resin layer. The substrate is then processed by sandblasting through the resin layer formed on the substrate from a photosensitive resin composition containing at least the components (A) to (C) in this way.

[0036] Next, the sandblasted resin layer is peeled off the substrate using the peeling solution according to the present invention. Methods for peeling from the substrate include the dip method, spray method, paddle method, and ultrasonic peeling. The dip method is preferred from a handling standpoint. The temperature of the peeling solution is preferably 15 to 60°C. Higher liquid temperatures result in faster peeling speeds, but components in the peeling solution volatilize, and deterioration of the solution may become significant when peeling large quantities.

[0037] The stripping solution according to the present invention contains at least 3-methoxy-N,N-dimethylpropanamide and / or 3-butoxy-N,N-dimethylpropanamide. The content of 3-methoxy-N,N-dimethylpropanamide and / or 3-butoxy-N,N-dimethylpropanamide in the stripping solution is preferably 80% by mass or more and 100% by mass or less. If the content is less than 80% by mass, the time required to peel the patterned resin layer from the substrate tends to increase.

[0038] The stripping solution according to the present invention may contain components other than those listed above as needed. Examples include water and organic solvents. Examples of organic solvents include alcohols, esters, ethers, and ketones. Examples include acetone, methyl ethyl ketone, cyclohexanenone, ethyl acetate, butyl acetate, ethanol, propanol, butanol, diethyl ether, and dioxane. It may also contain N-methylpyrrolidone and dimethyl sulfoxide. It may also contain surfactants, defoamers, and the like. [Examples]

[0039] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0040] (Examples)

[0041] The components of the photosensitive resin compositions shown in Table 1 were mixed to obtain coating solutions 1 and 2. The units for the content of each component in Table 1 are parts by mass. Next, each coating solution was applied to a 25 μm thick PET film, dried at 90°C for 8 minutes to remove the solvent components, and obtained photosensitive resin layers 1 and 2 (100 μm thick).

[0042] [Table 1]

[0043] In Table 1, the components are as follows: <Ingredient (A)> (A-1) KAYARAD UXF-4001-M35 (Product name, manufactured by Nippon Kayaku Co., Ltd., solid content 65% by mass, polyether-based urethane acrylate) (A-2) DURA-167 (Carboxylate-containing urethane acrylate manufactured by Kyoeisha Chemical Co., Ltd.) <Ingredient (B)> (B-1)2-(o-chlorophenyl)-4,5-diphenylimidazole dimer (B-2)N,N,N′,N′-Tetraethyl-4,4′-Diaminobenzophenone

[0044] <Component (C)> (C-1) Carboxylate-containing acrylic resin: Copolymer resin obtained by copolymerizing acrylic acid / styrene / n-butyl acrylate in a mass ratio of 30 / 50 / 20 (mass-average molecular weight 40,000, acid value 234 mgKOH / g, solids content 40% by mass, solvent: propylene glycol monomethyl ether) (C-2) Carboxylate-containing acrylic resin: Copolymer resin obtained by copolymerizing methyl methacrylate / n-butyl acrylate / methacrylic acid in a mass ratio of 64 / 15 / 21 (mass-average molecular weight 30,000, acid value 136 mg KOH / g, solids content 40% by mass, solvent: propylene glycol monomethyl ether)

[0045] TMP-A (product name, manufactured by Kyoeisha Chemical Co., Ltd., trimethylolpropane triacrylate)

[0046] Next, the fabricated photosensitive resin layers 1 and 2 were attached to a 1.0 mm thick aluminum nitride plate. Then, the photosensitive resin layers were exposed to light through a photomask. Next, the PET film was peeled off, and alkaline development was performed with a 1.0 mass% sodium carbonate aqueous solution to remove the unexposed areas of the photosensitive resin layer and form a resist pattern.

[0047] Next, a pattern was formed on the aluminum nitride plate by sandblasting it for 20 minutes using SiC abrasive material (manufactured by Naniwa Polishing Industry Co., Ltd., product name: GC Fine Powder #1200) via the patterned resin layer (spray pressure: 0.2 MPa).

[0048] Next, the stripping solutions for Examples 1-4 and Comparative Examples 1-3, shown in Table 2, were prepared. Note that the units for the amounts of each component in Table 1 represent parts by mass.

[0049] [Table 2]

[0050] Next, aluminum nitride substrates having resin layers 1 and 2 after sandblasting were immersed in stripping solutions at a liquid temperature of 20°C. In the stripping solutions of Examples 1 to 4, the resin layers were completely removed from the aluminum nitride substrates within 30 minutes of immersion. Furthermore, no corrosion or cracking occurred in the aluminum nitride substrates. In the stripping solution of Comparative Example 1, the resin layers could not be removed from the aluminum nitride substrates even after immersion for 60 minutes or more. In the stripping solutions of Comparative Examples 2 and 3, the resin layers were completely removed, but some corrosion occurred in the aluminum nitride substrates. In addition, in the method of removing the resin layers of aluminum nitride substrates having resin layers 1 and 2 after sandblasting by high-pressure water washing, although removal was possible in all cases, cracking was confirmed in the substrates. [Industrial applicability]

[0051] The peeling method of the present invention can be usefully used when peeling off a resin layer after sandblasting.

Claims

1. A method for peeling a patterned resin layer from a substrate, which is aluminum nitride or alumina, using a peeling solution after sandblasting, without causing corrosion or cracking of the substrate, wherein the patterned resin layer is formed from a photosensitive resin composition containing at least (A) urethane acrylate, (B) a photopolymerization initiator, and (C) an alkali-soluble resin, and the peeling solution contains at least 3-methoxy-N,N-dimethylpropanamide and / or 3-butoxy-N,N-dimethylpropanamide.

2. The stripping method according to claim 1, wherein the content of 3-methoxy-N,N-dimethylpropanamide and / or 3-butoxy-N,N-dimethylpropanamide in the stripping solution is 80% by mass or more and 100% by mass or less.