Curable resin composition, insulating cured film and insulating cured film for touch panel produced by curabing said composition, and touch panel

Abstract

Provided is a curable resin composition comprising: a thermosetting alkali-soluble resin (A1) having an acid value of 55-100 mgKOH / g; a photocurable alkali-soluble resin (A2); a (meth) acrylic monomer (B) having two polymerizable functional groups and a ring structure included between the two polymerizable functional groups; and a photopolymerization initiator (C). The mass ratio (A: B) of the total amount (A) of the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) to the total amount (B) of the (meth) acrylic monomer (B) is 100: 35-80.

Description

Technical Field

[0001] The present invention relates to a curable resin composition and an insulating cured film formed by curing the composition, for example, a curable resin composition useful for insulating cured film applications (e.g., insulating film applications, protective film applications, flat film applications, etc.) used in touch panels, etc., an insulating cured film for touch panels formed by curing the composition, and a touch panel having the cured film. Background Art

[0002] In recent years, with the development of electronic devices becoming more functional, diversified, small and lightweight, transparent touch panels are installed on the front surfaces of display elements such as liquid crystals. The text, symbols, patterns, etc. displayed by the display elements are viewed and selected through the transparent touch panels, and the functions of the equipment are switched by operating the transparent touch panels.

[0003] Touch panel detection methods include resistive film method, capacitive method, ultrasonic method, optical method, etc. In recent years, resistive film method and capacitive method have become popular. For example, the resistive film method is composed of a double-sided structure of an upper electrode film and a lower electrode glass, and a switch is pressed by applying pressure from above the upper electrode film with a pen tip or the like to react. In addition, the capacitive method is composed of a protective glass and a sensor glass on the surface, and an electrostatic coupling is generated by touching the surface glass with a finger, resulting in a capacitance difference with the inner glass, and the touched part is inferred based on the difference.

[0004] Capacitive touch panels use glass with an ITO film as the substrate. In order to prevent misidentification of the touch position, an insulating film and a protective film are provided in the laminated structure. As such a protective film, a high-hardness inorganic SiO2, SiN x , a protective film formed by transparent resins, etc., and an organic protective film. In addition, when the touch panel is combined with a liquid crystal display device, it can be divided into an out-cell structure, an on-cell structure, and an in-cell structure according to its setting location. In recent years, the surface-embedded structure and the in-cell structure with excellent visibility are becoming the mainstream. In these surface-embedded structures and in-cell structures, the touch panel is installed in the liquid crystal panel. Furthermore, as the structure of the touch panel, a double-sided type in which an X electrode is arranged on one side of the insulating film and a Y electrode is arranged on the other side, and a single-sided type in which an X electrode and a Y electrode are formed on the same plane are known.

[0005] As a technology applicable to such a touch panel, for example, a technology related to a cured film using a specific alkali-soluble resin and a photoreactive monomer and having excellent chemical resistance, developability, and wrinkle resistance has been proposed (for example, see Patent Document 1).

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: International Publication No. WO2020 / 251004 Summary of the invention

[0009] As described above, curable resin compositions are often used to form insulating films used in touch panels, liquid crystal display devices, etc. Such insulating films are sometimes patterned, and in particular, fine through holes (so-called through holes) are sometimes formed for the purpose of conducting between electrodes.

[0010] In order to form a fine pattern, it is advantageous to use a positive curable resin composition. However, when a positive curable resin composition is used, there is a problem that the cured product is colored.

[0011] On the other hand, in order to avoid coloring of the cured product, the use of a negative curable resin composition is also considered. However, it is difficult for existing negative curable compositions to form fine patterns, especially fine through holes, in an appropriate shape. Therefore, it is strongly desired to develop a technology that can form fine patterns, especially a technology that can form through holes with fine and good shapes (a technology with excellent through hole processability), although it is a negative curable resin composition.

[0012] The present invention aims to solve the above problems and to provide a curable resin composition capable of forming a fine pattern, particularly having excellent through-hole processability, an insulating cured film obtained by curing the composition, an insulating cured film for a touch panel, and a touch panel having the cured film.

[0013] The present inventors have conducted intensive studies to solve the above problems and have found that the above problems can be solved by using a composition containing a copolymer having a specific structure and a monomer having a specific structure at a specific ratio, thereby completing the present invention.

[0014] <1>

[0015] A curable resin composition comprising:

[0016] A thermosetting alkali-soluble resin (A1) having an acid value of 55 to 100 mgKOH / g,

[0017] Photocurable alkali-soluble resin (A2),

[0018] a (meth)acrylic monomer (B) having two polymerizable functional groups and a ring structure between the two polymerizable functional groups, and

[0019] Photopolymerization initiator (C);

[0020] The mass ratio [A:B] of the total amount [A] of the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) to the total amount [B] of the (meth)acrylic monomer (B) is 100:35-80.

[0021] <2>

[0022] The curable resin composition according to the above <1>, wherein the thermosetting alkali-soluble resin (A1) has an acid group and a cyclic ether group.

[0023] <3>

[0024] The curable resin composition according to <1> or <2>, wherein the thermosetting alkali-soluble resin (A1) contains at least the following units (a1-1) and (a1-2).

[0025]

[0026] (In unit (a1-1), R 1 represents a hydrogen atom or a methyl group, X 1 represents a single bond or a linear or cyclic aliphatic hydrocarbon group having 1 to 15 carbon atoms which may contain an oxygen atom. 1 represents a hydrogen atom or a methyl group, R 3 represents a linear or branched aliphatic hydrocarbon group having 3 to 15 carbon atoms and having a cyclic ether structure and optionally containing an oxygen atom)

[0027] <4>

[0028] The curable resin composition according to the above <3>, wherein the thermosetting alkali-soluble resin (A1) further includes the following unit (a1-3).

[0029]

[0030] (Where R 1 represents a hydrogen atom or a methyl group, R 4 represents at least one selected from a linear, branched or cyclic aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatic group and a combination thereof which may contain an oxygen atom)

[0031] <5>

[0032] The curable resin composition according to any one of <1> to <4>, wherein the photocurable alkali-soluble resin (A2) has an acid value of 70 mgKOH / g or less.

[0033] <6>

[0034] The curable resin composition according to any one of <1> to <5>, wherein the photocurable alkali-soluble resin (A2) contains at least the following units (a2-1) and (a2-2).

[0035]

[0036] (In unit (a2-1), R 1 Each independently represents a hydrogen atom or a methyl group, R 5 represents a chain, branched or cyclic aliphatic hydrocarbon group having 2 to 15 carbon atoms which may contain a hetero atom. 1 represents a hydrogen atom or a methyl group, X 1 represents a single bond or a linear or cyclic aliphatic hydrocarbon group having 1 to 15 carbon atoms which may contain an oxygen atom)

[0037] <7>

[0038] The curable resin composition according to the above <6>, wherein the photocurable alkali-soluble resin (A2) further includes the following unit (a2-3).

[0039]

[0040] (Where R 1 represents a hydrogen atom or a methyl group, R 4 represents at least one selected from a linear, branched or cyclic aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatic group, and a combination thereof which may contain an oxygen atom)

[0041] <8>

[0042] The curable resin composition according to any one of <1> to <7>, wherein the weight average molecular weight of the photocurable alkali-soluble resin (A2) is 20,000 or less.

[0043] <9>

[0044] The curable resin composition according to any one of <1> to <8>, wherein at least one of the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) has a cyclic group.

[0045] <10>

[0046] The curable resin composition according to any one of <1> to <9>, wherein the ring structure in the (meth)acrylic monomer (B) is any one selected from an aliphatic hydrocarbon group having 6 to 26 carbon atoms which may contain an oxygen atom, an aromatic hydrocarbon group having 6 to 26 carbon atoms which may contain an oxygen atom, and a combination thereof.

[0047] <11>

[0048] The curable resin composition according to any one of <1> to <10>, wherein the two polymerizable functional groups in the (meth)acrylic monomer (B) include acryloyl groups.

[0049] <12>

[0050] The curable resin composition according to any one of <1> to <11>, wherein the (meth)acrylic monomer (B) is a compound represented by the following formula (b1).

[0051]

[0052] (Where R 11 and R 12 Each independently represents a hydrogen atom or a methyl group, Y 1 and Y 2 Each independently represents a single bond, or a linear or branched aliphatic hydrocarbon group having 1 to 26 carbon atoms which may contain an oxygen atom, and X 11 W1 represents an aliphatic hydrocarbon group or an aromatic group having 6 to 26 carbon atoms and a cyclic skeleton, and W1 and W2 each independently represent O, N or S.

[0053] <13>

[0054] The curable resin composition according to any one of <1> to <12>, which is used for forming an insulating film.

[0055] <14>

[0056] An insulating cured film obtained by curing the curable resin composition according to any one of <1> to <12> above.

[0057] <15>

[0058] An insulating cured film for a touch panel, obtained by curing the curable resin composition described in any one of <1> to <12> above.

[0059] <16>

[0060] A touch panel comprises the insulating cured film for a touch panel according to <15>.

[0061] According to the present invention, there can be provided a curable resin composition capable of forming a fine pattern, particularly having excellent through-hole processability, an insulating cured film obtained by curing the composition, an insulating cured film for a touch panel, and a touch panel having the cured film. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a plan view showing the structure of one mode of the touch panel according to the present embodiment.

[0063] Figure 2 yes Figure 1 AA cross-section diagram.

[0064] Figure 3 It is a schematic diagram showing the cross-sectional shape of a through hole. DETAILED DESCRIPTION

[0065] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "this embodiment") will be described in detail. However, the present invention is not limited thereto, and various modifications can be made without departing from the gist of the present invention.

[0066] 《Curable resin composition》

[0067] The curable resin composition of the present embodiment comprises: a thermosetting alkali-soluble resin (A1) having an acid value of 55 to 100 mgKOH / g, a photocurable alkali-soluble resin (A2), a (meth)acrylic monomer (B) having two polymerizable functional groups and a ring structure contained between the two polymerizable functional groups, and a photopolymerization initiator (C); the mass ratio [A:B] of the total amount [A] of the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) to the total amount [B] of the (meth)acrylic monomer (B) is 100:35 to 80.

[0068] The curable resin composition of the present embodiment can form a fine pattern, especially the processability of the through hole is excellent. Although it is a negative composition, it can form a through hole with a desired size that is fully open to the side of the hole and the hole cross-sectional shape is an inverted trapezoidal shape when viewed from the exposure direction. The curable resin composition of the present embodiment can form a fine pattern, especially the reason for the excellent processability of the through hole is still uncertain. First, it is speculated that one reason is that since the curable resin composition of the present embodiment contains a thermosetting alkali-soluble resin (A1) and a photocurable alkali-soluble resin (A2) and a (meth) acrylic monomer in a specific ratio, the non-latent image portion (non-exposure portion) when making the through hole has excellent developability, and the latent image portion (exposure portion) has high resistance to the developer. Furthermore, it is speculated that since the curable resin composition of the present embodiment contains a thermosetting alkali-soluble resin, the wall surface of the through hole will not collapse due to the heat during the post-baking after development, and the hole cross-sectional shape can be kept as an inverted trapezoidal shape when viewed from the exposure direction.

[0069] <Alkali-soluble resin (A)>

[0070] The curable resin composition of the present embodiment comprises a thermosetting alkali-soluble resin (A1) and a photocurable alkali-soluble resin (A2). The thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) are different compounds. For the "alkali-soluble resin", the non-cured portion shows solubility in the developer, and the cured portion shows insolubility or poor solubility in the developer. In addition, from the viewpoint of the resistance of the cured product to the developer (hereinafter referred to as "resistance to the developer"), it is preferred that at least one of the thermosetting alkali-soluble resin (A1) and the above-mentioned photocurable alkali-soluble resin (A2) has a cyclic group.

[0071] Hereinafter, the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) are sometimes referred to as "alkali-soluble resin (A1)" or "alkali-soluble resin (A2)", respectively. In addition, the alkali-soluble resins (A1) and (A2) are sometimes collectively referred to as "alkali-soluble resin (A)". The curable resin composition of this embodiment may contain a plurality of alkali-soluble resins (A1) and (A2).

[0072] (Thermosetting alkali-soluble resin (A1))

[0073] The alkali-soluble resin (A1) is a thermosetting alkali-soluble resin having an acid value of 55 to 100 mgKOH / g. The alkali-soluble resin (A1) is a resin having a thermoreactive group and being cured at 70°C or above. The thermoreactive group is not particularly limited, and from the perspective of low-temperature curability, for example, an acid group (e.g., a carboxyl group, an acid anhydride group, a sulfonic group, a phosphoric acid group), a cyclic ether group, a hydroxyl group, an amino group, a thiol group, an isocyanate group, a silanol group, etc. can be cited. The alkali-soluble resin (A1) preferably has an acid group and a cyclic ether group (e.g., an epoxy group, an oxetane group, etc.) as a thermoreactive group. The temperature at which the thermosetting alkali-soluble resin (A1) is cured varies depending on the type and number of the thermoreactive group. From the perspective of low-temperature curability and the developability of the unexposed portion (the solubility of the unexposed portion in the developer), it is 70°C or above, preferably 80°C to 230°C, and more preferably 90°C to 150°C.

[0074] The acid value of the alkali-soluble resin (A1) is 55 to 100 mgKOH / g, more preferably 60 to 95 mgKOH / g, and more preferably 70 to 90 mgKOH / g. If the acid value of the alkali-soluble resin (A1) is within the range of 55 to 100 mgKOH / g, poor development can be suppressed, and the developer (e.g., tetramethylammonium hydroxide) has high resistance, which can suppress overdevelopment. In addition, if the acid value is less than 55 mgKOH / g, the developability may be reduced. As the acid value of the alkali-soluble resin, the theoretical solid content acid value can be used, which can be calculated as follows.

[0075] Theoretical solid content acid value (mgKOH / g) = [56.1 (molecular weight of potassium hydroxide) × (total amount of acid group-containing units in alkali-soluble resin (A1) [g]) × 1000] / [(total amount of solid content of alkali-soluble resin (A1) [g]) × (molecular weight of acid group-containing units)]

[0076] As the thermosetting alkali-soluble resin (A1), a resin containing at least the following units (a1-1) and (a1-2) can be used. The thermosetting alkali-soluble resin (A1) can be a resin containing two or more of the following identical constituent units (for example, two units (a1-2)).

[0077]

[0078] (In unit (a1-1), R 1 represents a hydrogen atom or a methyl group, X 1 represents a single bond or a linear or cyclic aliphatic hydrocarbon group having 1 to 15 carbon atoms which may contain an oxygen atom. 1 represents a hydrogen atom or a methyl group, R 3 represents a linear or branched aliphatic hydrocarbon group having 3 to 15 carbon atoms and having a cyclic ether structure and optionally containing an oxygen atom)

[0079] -Unit (a1-1)-

[0080] The unit (a1-1) is a unit derived from an unsaturated carboxylic acid.

[0081] In unit (a1-1), R 1 represents a hydrogen atom or a methyl group, and is preferably a methyl group from the viewpoint of heat resistance of the obtained cured product (meaning that the shape of the cured product is less likely to change due to heat. Hereinafter, simply referred to as "heat resistance").

[0082] In addition, X 1 represents a single bond, or a linear or cyclic aliphatic hydrocarbon group (divalent bonding group) having 1 to 15 carbon atoms which may contain an oxygen atom. From the viewpoint of heat resistance, the carbon number of the aliphatic hydrocarbon group which may contain an oxygen atom is preferably 1 to 9. These aliphatic hydrocarbon groups may have an -O- structure in the structure (structure containing an oxygen atom: for example, an ether group (-O-), an ester group (-CO-O-), an anhydride group (-CO-O-CO-)). Examples of linear aliphatic hydrocarbon groups include alkylene groups having 1 to 15 carbon atoms, aliphatic hydrocarbon groups having 3 to 15 carbon atoms which may contain a plurality of ester groups or anhydride groups (-CO-O-CO-), and the like. In addition, examples of cyclic aliphatic hydrocarbon groups include cycloalkylene groups having 3 to 15 carbon atoms, a cycloalkylene group having 3 to 15 carbon atoms which may contain a plurality of ester groups or anhydride groups, and the like. In addition, X 1It may be an aliphatic hydrocarbon group containing both a linear portion and a cyclic portion. 1 Examples include -CO-O-CH2-CH2-O-CO-CH2-CH2-, -CO-O-CH2-CH2-O-CO-cyclohexyl-, and the like.

[0083] As the unit (a1-1), for example, methacrylic acid (hereinafter sometimes referred to as "MAA"), acrylic acid, crotonic acid (trans), maleic acid (cis), fumaric acid (trans), citraconic acid (cis), mesaconic acid (trans), itaconic acid, maleic anhydride, citraconic anhydride, itaconic anhydride, hexahydrophthalic acid-2-methacryloyloxyethyl ester, etc. As a preferred structure of the unit (a1-1), units derived from the following compounds can be exemplified.

[0084]

[0085] -Unit (a1-2)-

[0086] The unit (a1-2) is a unit derived from an unsaturated carboxylic acid having a cyclic ether structure.

[0087] In the following unit (a1-2), R 1 represents a hydrogen atom or a methyl group, R 3 It represents a linear or branched aliphatic hydrocarbon group having 3 to 15 carbon atoms which has a cyclic ether structure and may contain an oxygen atom.

[0088]

[0089] In unit (a1-2), R 1 represents a hydrogen atom or a methyl group, and is preferably a methyl group from the viewpoint of heat resistance.

[0090] In addition, R 3 It represents a linear or branched aliphatic hydrocarbon group having 3 to 15 carbon atoms which has a cyclic ether structure and may contain an oxygen atom.

[0091] Here, from the viewpoint of developability, the number of carbon atoms of the straight-chain or branched aliphatic hydrocarbon group having a cyclic ether structure is preferably 3 to 7. These aliphatic hydrocarbon groups may have an -O- structure (a structure containing an oxygen atom: for example, an ether group (-O-), an ester group (-CO-O-), an anhydride group (-CO-O-CO-)) in the structure. As a straight-chain or branched aliphatic hydrocarbon group having a cyclic ether structure, a group having a cyclic ether structure bonded to the end of an alkylene group (for example, a methylene group) and the like can be cited. As a preferred structure of the unit (a1-2), units derived from the following compounds can be exemplified.

[0092]

[0093] -Unit (a1-3)-

[0094] As the thermosetting alkali-soluble resin (A1), a resin containing the following unit (a1-3) in addition to the above-mentioned units (a1-1) and (a1-2) can be used from the viewpoint of resistance to a developer. The unit (a1-3) is a unit derived from an unsaturated compound.

[0095]

[0096] (Where R 1 represents a hydrogen atom or a methyl group, R 4 represents at least one selected from a linear, branched or cyclic aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatic group and a combination thereof which may contain an oxygen atom)

[0097] In unit (a1-3), R 1 represents a hydrogen atom or a methyl group, and is preferably a methyl group from the viewpoint of heat resistance.

[0098] In addition, R 4 It is a straight-chain, branched or cyclic aliphatic hydrocarbon group with 1 to 20 carbon atoms, an aromatic group, or a combination of the above aliphatic hydrocarbon and aromatic group. Here, from the viewpoint of resistance to developer and developability, the carbon number of the above aliphatic hydrocarbon group is preferably 1 to 10. These aliphatic hydrocarbon groups may have an -O- structure (a structure containing an oxygen atom: for example, an ether group (-O-), an ester group (-CO-O-), an acid anhydride group (-CO-O-CO-)) in the structure. As the above straight-chain, branched or cyclic aliphatic hydrocarbon group, a straight-chain, branched or cyclic alkyl group with 1 to 20 carbon atoms can be cited. From the aspect of resistance to developer, methyl, n-propyl, n-butyl, n-hexyl, cyclopentyl, cyclohexyl, isobornyl, tricyclodecanyl, and adamantyl are preferred. In addition, as the above aromatic group, phenyl, biphenyl, naphthyl, anthracenyl, etc. can be cited. From the aspect of transparency of the cured product, phenyl is preferred. In addition, as a combination of an aliphatic hydrocarbon group having 1 to 20 carbon atoms and an aromatic group, alkoxyphenyl, alkylphenyl, alkoxynaphthyl, alkylnaphthyl, alkoxyanthryl, alkylanthryl, etc. can be cited, and from the perspective of the transparency of the cured product, alkoxyphenyl and alkylphenyl are preferred. As a preferred structure of unit (a1-3), units from the following compounds can be exemplified.

[0099]

[0100] - Composition ratio -

[0101] From the viewpoint of resistance to developer and developability, the content (mol %) of units (a1-1), units (a1-2) and units (a1-3) in the alkali-soluble resin (A) is preferably (a1-1) / (a1-2) / (a1-3) = 10 to 50 / 10 to 70 / 0 to 70, more preferably 15 to 40 / 15 to 60 / 15 to 65, and particularly preferably 15 to 30 / 20 to 50 / 30 to 60.

[0102] -Other components-

[0103] The alkali-soluble resin (A1) may contain other structural units that do not belong to any of the above-mentioned units (a1-1) to (a1-3). Examples of other structural units include 1,3-bis(methacryloyloxy)-2-propanol, 2-methacryloyloxyethyl isocyanate, 2-hydroxyethyl methacrylate, and N-cyclohexylsuccinimide.

[0104] The content (mol %) of other structural units in the alkali-soluble resin (A1) is preferably 0 to 35 mol %, more preferably 0 to 20 mol %, from the viewpoint of resistance to a developer and developability.

[0105] (Molecular weight)

[0106] From the viewpoint of developability, the weight average molecular weight of the alkali-soluble resin (A1) is preferably 3000 to 30000, more preferably 4000 to 25000, and particularly preferably 5000 to 20000. The molecular weight of the alkali-soluble resin (A) can be measured by gel permeation chromatography (manufactured by Tosoh Corporation, model: HLC-8120, column: G-5000HXL and G-3000HXL connected, detector: RI, mobile phase: tetrahydrofuran).

[0107] (Glass transition temperature)

[0108] From the viewpoint of heat resistance, developability and low-temperature curability, the glass transition temperature of the alkali-soluble resin (A1) is preferably 0 to 300° C., more preferably 30 to 250° C., particularly preferably 50 to 200° C. The glass transition temperature can be measured by differential scanning calorimetry (DSC).

[0109] (Epoxy Equivalent Weight)

[0110] From the viewpoint of achieving both resistance to a developer and developability, the epoxy equivalent of the alkali-soluble resin (A1) is preferably 200 to 1000, more preferably 250 to 800, and particularly preferably 300 to 600. The epoxy equivalent can be determined, for example, in accordance with JIS K7236 (2001).

[0111] (Double bond equivalent)

[0112] From the viewpoint of heat resistance and reactivity, the double bond equivalent of the alkali-soluble resin (A1) is preferably 150 to 2000, more preferably 150 to 1500, and particularly preferably 200 to 1000. The double bond equivalent can be obtained, for example, by "(mass per mol of polymer) / (number of ethylenically unsaturated groups per mol)".

[0113] (specific example)

[0114] Specific examples of the alkali-soluble resin (A1) include the following polymers.

[0115]

[0116] (Photocurable alkali-soluble resin (A2))

[0117] The alkali-soluble resin (A2) is a resin cured by free radicals from a photopolymerization initiator (C). The alkali-soluble resin (A2) preferably has an ethylenically unsaturated double bond as a functional group that reacts with free radicals. The ethylenically unsaturated double bond is not particularly limited, and from the perspective of chemical resistance of the resulting cured product, for example, (meth)acryloyl, vinyl, and allyl groups can be cited, preferably (meth)acryloyl.

[0118] As the photocurable alkali-soluble resin (A2), a resin containing at least the following units (a2-1) and (a2-2) can be used. The photocurable alkali-soluble resin (A2) can be a resin containing two or more of the same constituent units (for example, two units (a2-2)) described below.

[0119]

[0120] (In unit (a2-1), R 1 Each independently represents a hydrogen atom or a methyl group, R 5 represents a chain, branched or cyclic aliphatic hydrocarbon group having 2 to 15 carbon atoms which may contain a hetero atom. 1 represents a hydrogen atom or a methyl group, X 1 represents a single bond or a linear or cyclic aliphatic hydrocarbon group having 1 to 15 carbon atoms which may contain an oxygen atom)

[0121] -Unit (a2-1)-

[0122] The unit (a2-1) is a unit derived from an unsaturated compound having a (meth)acryloyl group.

[0123] In unit (a2-1), R 1Each independently represents a hydrogen atom or a methyl group, and a methyl group is preferred from the viewpoint of heat resistance.

[0124] In addition, R 5 It represents a chain, branched or cyclic aliphatic hydrocarbon group (divalent bonding group) having 2 to 15 carbon atoms which may contain heteroatoms. From the viewpoint of the reactivity of the composition, the carbon number of the aliphatic hydrocarbon group which may contain heteroatoms is preferably 3 to 10. These aliphatic hydrocarbon groups may have an -O- structure (a structure containing an oxygen atom: for example, -OH (hydroxyl), ether group (-O-), ester group (-CO-O-), acid anhydride group (-CO-O-CO-)), a structure containing a sulfur atom such as an -S- structure, and a structure containing a nitrogen atom such as an -NH- structure. Examples of the straight-chain or branched aliphatic hydrocarbon group include an alkylene group having 2 to 15 carbon atoms, an aliphatic hydrocarbon group having 2 to 15 carbon atoms which may contain a plurality of ester groups and acid anhydride groups (-CO-O-CO-), and the like. In addition, examples of the cyclic aliphatic hydrocarbon group include a cycloalkylene group having 3 to 15 carbon atoms, a cycloalkylene group having 3 to 15 carbon atoms which may contain a plurality of ester groups and acid anhydride groups, and the like. In addition, R 5 It may be an aliphatic hydrocarbon group containing both a straight chain portion and a cyclic portion. 5 Examples include -CH2-CH(OH)-CH2-, -CH2-CH2-O-CO-NH-CH2-CH2-O-, -CO-O-CH2-CH(OH)-CH2-O-, -CO-O-CH2-CH2-O-CO-NH-CH2-CH2-O-, -CO-O-CH2-CH2-CH2-O-CO-NH-CH2-CH2-O-, -CO-O-CH2-CH2-CH2-CH2-O-CO-NH-CH2-CH2-O-, etc.

[0125] Preferred structures of the unit (a2-1) include units derived from the following compounds.

[0126]

[0127] -Unit (a2-2)-

[0128] The unit (a2-2) is a unit derived from an unsaturated carboxylic acid and has the same structure as the above-mentioned unit (a1-1).

[0129] In unit (a2-2), R 1 , X 1 and R in unit (a1-1) 1 , X 1 The meanings are the same, and the preferred specific examples are also the same.

[0130] -Unit (a2-3)-

[0131] From the viewpoint of resistance to a developer, as the photocurable alkali-soluble resin (A2), a resin containing the following unit (a2-3) in addition to the above-mentioned units (a2-1) and (a2-2) can be used.

[0132]

[0133] (Where R 1 represents a hydrogen atom or a methyl group, R 4 represents at least one selected from a linear, branched or cyclic aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatic group and a combination thereof which may contain an oxygen atom)

[0134] The unit (a2-3) is a unit derived from an unsaturated compound and has the same structure as the above-mentioned unit (a1-3).

[0135] In unit (a2-3), R 1 , R 4 and R in unit (a1-1) 1 , R 4 The meanings are the same, and the preferred specific examples are also the same.

[0136] - Composition ratio -

[0137] From the viewpoint of achieving both resistance to the developer and developability, the content (molar %) of units (a2-1), units (a2-2) and units (a2-3) in the alkali-soluble resin (A2) is preferably (a2-1) / (a2-2) / (a2-3) = 10 to 70 / 1 to 50 / 0 to 70, more preferably 15 to 60 / 5 to 40 / 0 to 60, and particularly preferably 20 to 50 / 10 to 30 / 0 to 50.

[0138] -Other components-

[0139] The alkali-soluble resin (A2) may contain other structural units that do not belong to any of the above-mentioned units (a2-1) to (a2-3). Examples of other structural units include benzyl methacrylate, 2-methacryloyloxyethyl isocyanate, 2-hydroxyethyl methacrylate, and N-cyclohexylsuccinimide.

[0140] From the viewpoint of achieving both resistance to a developer and developability, the content (mol %) of other structural units in the alkali-soluble resin (A2) is preferably 0 to 30 mol %, more preferably 0 to 15 mol %.

[0141] (Molecular weight)

[0142] From the viewpoint of developability, the weight average molecular weight of the alkali-soluble resin (A2) may be, for example, 20,000 or less, preferably 500 to 20,000, more preferably 1,000 to 15,000, and even more preferably 2,000 to 10,000. The molecular weight of the alkali-soluble resin (A2) can be measured in the same manner as the alkali-soluble resin (A1).

[0143] (Acid value)

[0144] From the viewpoint of achieving both resistance to developer and developability, the acid value of the alkali-soluble resin (A2) is preferably 70 mgKOH / g or less, preferably 10 to 60 mgKOH / g or less, and more preferably 20 to 60 mgKOH / g. As the acid value of the alkali-soluble resin, the above-mentioned theoretical solid content acid value can be used.

[0145] (Glass transition temperature)

[0146] From the viewpoint of heat resistance and developability, the glass transition temperature of the alkali-soluble resin (A2) is preferably 0 to 300° C., more preferably 30 to 250° C., and particularly preferably 50 to 200° C. The glass transition temperature can be measured by a differential scanning calorimeter (DSC).

[0147] (Double bond equivalent)

[0148] From the viewpoint of reactivity and developability, the double bond equivalent of the alkali-soluble resin (A2) is preferably 150 to 2000, more preferably 150 to 1500, and particularly preferably 200 to 1000. The double bond equivalent can be determined in the same manner as for the alkali-soluble resin (A1).

[0149] (specific example)

[0150] Specific examples of the alkali-soluble resin (A2) include the following polymers.

[0151]

[0152] (content)

[0153] The content of the alkali-soluble resin (A) in the curable resin composition of the present embodiment (the total amount of the alkali-soluble resin (A1) and the alkali-soluble resin (A2)) is not particularly limited, and for example, from the viewpoint of developability, it is preferably 30 to 80% by mass, more preferably 40 to 70% by mass, and particularly preferably 45 to 65% by mass relative to the total solid content in the composition. In this specification, "total solid content" refers to all components in the resin composition excluding the solvent.

[0154] (Combination of Alkali-Soluble Resin (A1) and Alkali-Soluble Resin (A2))

[0155] The mass ratio of the alkali-soluble resin (A1) to the alkali-soluble resin (A2) in the curable resin composition of the present embodiment is not particularly limited. For example, from the viewpoint of low-temperature curability, the mass ratio (A1): (A2) is preferably 100:1 to 100, more preferably 100:5 to 60, and particularly preferably 100:10 to 50.

[0156] <Other polymers>

[0157] The curable resin composition of the present embodiment may contain other polymers in addition to the alkali-soluble resin (A). The content of other polymers in the curable resin composition of the present embodiment is not particularly limited, for example, from the viewpoint of obtaining the effect brought by including other polymers without significantly hindering the chemical resistance of the cured film, etc., relative to 100 parts by mass of the alkali-soluble resin (A), preferably 5 to 30 parts by mass, more preferably 10 to 20 parts by mass.

[0158] <(Meth)acrylic acid monomer (B)>

[0159] The (meth)acrylic monomer (B) is a compound having two polymerizable functional groups and a ring structure contained between the two polymerizable functional groups, and has at least one (meth)acryloyl group. The curable resin composition of the present embodiment can improve through-hole processability by using the (meth)acrylic monomer (B).

[0160] Here, "ring structure" refers to a structure having at least one cyclic skeleton, and includes structures consisting only of a cyclic skeleton and structures consisting of a cyclic skeleton and a linear structure bonded to the cyclic skeleton. In addition, "ring structure contained between two polymerizable functional groups" means that two polymerizable functional groups are bonded via a ring structure, and the polymerizable functional group can be directly bonded to the cyclic skeleton or indirectly bonded to the cyclic skeleton. From the viewpoint of resistance to developer, the ring structure of the (meth)acrylic monomer (B) can be any one selected from aliphatic hydrocarbon groups having 6 to 26 carbon atoms that can contain oxygen atoms, aromatic hydrocarbons having 6 to 26 carbon atoms that can contain oxygen atoms, and combinations thereof (for example, combinations of aliphatic hydrocarbons and aromatic hydrocarbons, and combinations of different aliphatic hydrocarbons, different aromatic hydrocarbon compounds, etc.). As specific examples of cyclic skeletons, for example, fluorene skeletons, cyclohexane skeletons, bisphenol A skeletons, dicyclopentane skeletons, and combinations thereof can be cited.

[0161] "Polymerizable functional group" is a (meth)acryloyl group itself, a group containing one (meth)acryloyl group, or a functional group containing one polymerizable group other than a (meth)acryloyl group. Examples of polymerizable functional groups other than a (meth)acryloyl group include vinyl, allyl, (meth)acrylamide, and the like. Hereinafter, "a group containing a (meth)acryloyl group" refers to a (meth)acryloyl group itself or a group containing one (meth)acryloyl group. It is preferred that the two polymerizable functional groups of the (meth)acrylic monomer (B) are groups containing a (meth)acryloyl group, and it is preferred that at least one of the two polymerizable functional groups is an acryloyl group. In the (meth)acrylic monomer (B), the number of polymerizable functional groups is 2. If the number of polymerizable functional groups exceeds 2, the through-hole processability is sometimes reduced. In addition, the types of the two polymerizable functional groups may be the same or different from each other.

[0162] As the (meth)acrylic monomer (B), a compound represented by the following formula (b1) can be used.

[0163]

[0164] (Where R 11 and R 12 Each independently represents a hydrogen atom or a methyl group, Y 1 and Y 2 Each independently represents a single bond, or a linear or branched aliphatic hydrocarbon group having 1 to 26 carbon atoms which may contain an oxygen atom, and X 11 represents an aliphatic hydrocarbon group or aromatic group having 6 to 26 carbon atoms and a cyclic skeleton, W1 and W2 each independently represent O, N or S)

[0165] In formula (b1), R 11 and R 12 Each independently represents a hydrogen atom or a methyl group, and from the viewpoint of the composition showing good curability (hereinafter referred to as "curability") during exposure to light, a hydrogen atom is preferred.

[0166] Y 1 and Y 2 Each independently represents a single bond, or a linear or branched aliphatic hydrocarbon group (divalent bonding group) having 1 to 26 carbon atoms which may contain an oxygen atom. From the viewpoint of curability, the carbon number of the aliphatic hydrocarbon group is preferably 1 to 20, and more preferably 1 to 12. Examples of the linear or branched aliphatic hydrocarbon group include alkylene groups having 1 to 26 carbon atoms, such as methylene, ethylene, 1-methylethylene, 1-methylpropylene, 2-methylpropylene, and 1,1-dimethylethylene. In addition, Y containing an oxygen atom may be 1 and Y 2 For example, -O(C2H4O)m - (m is 1 to 13), etc. 1 and Y 2 , for example, a methylene group is preferred.

[0167] X 11 represents an aliphatic hydrocarbon group or aromatic group (divalent bonding group) having 6 to 26 carbon atoms and a cyclic skeleton. 11 The number of carbon atoms in the moiety is preferably 6 to 26.

[0168] Examples of the aliphatic hydrocarbon having 6 to 26 carbon atoms and having the cyclic skeleton include a divalent bonding group consisting of a cyclohexane ring, a cyclodecane ring, a tricyclodecane ring, an adamantane ring, a norbornane ring or a decalin ring, and examples of the aromatic group include a divalent bonding group consisting of a benzene ring or a naphthalene ring. 11 , preferably containing at least one divalent bonding group selected from the above-mentioned fluorene skeleton, cyclohexane skeleton, bisphenol A skeleton, dicyclopentane skeleton and a combination thereof.

[0169] The (meth)acrylic monomer (B) is not particularly limited, but the following compounds may be mentioned.

[0170]

[0171] From the viewpoint of the developability when forming a through hole, the content of the (meth) acrylic monomer (B) in the curable resin composition of the present embodiment is set in such a manner that the mass ratio [A:B] of the total amount [A] of the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) to the total amount [B] of the (meth) acrylic monomer (B) is 100:35 to 80. If the total amount [B] of the (meth) acrylic monomer (B) is less than 35 parts by mass relative to 100 parts by mass of the total amount [A] of the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2), the developability when forming a through hole may be reduced. From the viewpoint of through hole processability, the mass ratio [A:B] is preferably 100:40 to 75, and more preferably 100:45 to 70.

[0172] In addition, although not particularly limited, from the viewpoint of balancing resistance to developer and developability, the combination of the alkali-soluble resin (A1), the alkali-soluble resin (A2) and the (meth)acrylic monomer (B) may be, for example, A1:A2:B=100:5-40:35-110, or 100:10-30:50-100.

[0173] In addition, the curable resin composition of the present embodiment may contain a photoreactive monomer other than the (meth) acrylic monomer (B). Other photoreactive monomers are not particularly limited, and for example, compounds having three or more ethylenically unsaturated groups in the molecule may be cited. Examples of such compounds include trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, and the like.

[0174] (Double bond equivalent)

[0175] From the viewpoint of reactivity and developability, the double bond equivalent of the (meth)acrylic monomer (B) is preferably 120 to 1000, more preferably 120 to 800, and particularly preferably 120 to 600. The double bond equivalent can be calculated according to (molecular weight of (meth)acrylic monomer (B)) / (the number of ethylenically unsaturated groups in (meth)acrylic monomer (B)).

[0176] (LogP)

[0177] The (meth)acrylic monomer (B) preferably has a LogP of 1 to 8, more preferably 1.5 to 7, further preferably 2 to 6, particularly preferably 2.5 to 6, and most preferably 3 to 5, from the viewpoint of resistance to a developer and developability.

[0178] The LogP can be determined by using a reverse phase column (C18) and HPLC (high performance liquid chromatography) according to OECD GUIDELINES FOR THE TESTING CHEMICALS Partition Coefficient (n-octanol / water), High Performance Liquid Chromatography (HPLC) Method 117 (Adopted 13 April 2004). Benzyl alcohol, anisole, toluene, and butylbenzene are used as standard substances with known LogP.

[0179] Examples of the measurement conditions of LogP are as follows.

[0180] · Apparatus: 1200 Series HPLC manufactured by Agilent Technology

[0181] Column: DiKMA Inspire C18 5 μm 150×4.6 mm (particle size 5 μm, inner diameter 4.6 mm, length 150 mm)

[0182] Mobile phase: a mixture of acetonitrile and 0.5 wt% phosphoric acid aqueous solution {mixing ratio 55:45 (volume ratio)}

[0183] Oven temperature: 40℃

[0184] Flow rate: 1mL / min

[0185] UV detection wavelength: 210nm

[0186] (Photopolymerization initiator (C))

[0187] The curable resin composition of the present embodiment is a negative curable resin composition containing a photopolymerization initiator (C). The photopolymerization initiator is a compound that is activated by various active light rays, such as ultraviolet rays, to initiate polymerization. As the photopolymerization initiator, for example, free radical photopolymerization initiators, cationic photopolymerization initiators, and anionic photopolymerization initiators can be cited. The photopolymerization initiator (C) is not particularly limited, and for example, a photopolymerization initiator that generates free radicals that polymerize ethylenically unsaturated groups by ultraviolet rays to visible rays can be appropriately used.

[0188] The photopolymerization initiator is not particularly limited, and examples thereof include acetophenones such as acetophenone, 2,2'-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, and p-tert-butylacetophenone; α-aminoketone photopolymerization initiators such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butane-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholino-4-yl-phenyl)-butane-1-one, and 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one; 1-[4-(phenylthio)phenyl]octane-1,2-dione = 2-(O-benzoyl oxime), 1-[9-ethyl- 6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyl oxime), 1-[9-ethyl-6-benzoyl-9.H.-carbazol-3-yl]-octane-1-one oxime-O-acetate, 1-[9-ethyl-6-(2-methylbenzoyl)-9.H.-carbazol-3-yl]-ethane-1-one oxime-O-benzoate, 1-[9-n-butyl-6-(2-ethylbenzoyl)-9.H.-carbazol-3-yl]-ethane-1-one oxime-O-benzoate, 1-[9-ethyl-6-(2-methyl-4-tetrahydrofuranylbenzoyl)-9.H.-carbazol-3-yl]ethanone-1-(O-acetyl oxime), 1-[9-ethyl-6-( Oxime ester photopolymerization initiators such as 1-[2-methyl-4-tetrahydropyranylbenzoyl)-9.H.-carbazole-3-yl]ethanone-1-(O-acetoxime), 1-[9-ethyl-6-(2-methyl-5-tetrahydrofuranylbenzoyl)-9.H.-carbazole-3-yl]ethanone-1-(O-acetoxime), 1-[9-ethyl-6-{2-methyl-4-(2,2-dimethyl-1,3-dioxolyl)methoxybenzoyl}-9.H.-carbazole-3-yl]ethanone-1-(O-acetoxime); benzophenones such as benzophenone, 2-chlorobenzophenone, and p,p'-bisdimethylaminobenzophenone; benzil, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether ethers such as benzoin ethers; sulfur compounds such as benzil dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone; anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone; triazines such as 2,4-trichloromethyl-(4'-methoxyphenyl)-6-triazine, 2,4-trichloromethyl-(4'-methoxynaphthyl)-6-triazine, 2,4-trichloromethyl-(piperonyl)-6-triazine, 2,4-trichloromethyl-(4'-methoxyphenyl)-6-triazine; organic peroxides such as azobisisobutyronitrile, benzoyl peroxide, and isopropyl peroxide; 2-mercaptobenzimidazole, 2-mercaptobenzoic acid The photopolymerization initiator (C) is preferably an oxime ester photopolymerization initiator, or a thiol compound such as oxazole, 2-mercaptobenzothiazole, etc. From the viewpoint of both resistance to the developer and developability, an oxime ester photopolymerization initiator is preferred. These photopolymerization initiators may be used alone or in combination of two or more.

[0189] The content of the photopolymerization initiator (C) in the curable resin composition of the present embodiment is not particularly limited. For example, from the viewpoint of photoreactivity and storage stability, when the total amount of the (meth)acrylic monomer (B), the photoreactive monomer and the photocurable alkali-soluble resin (A2) is 100 parts by mass, it is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, and particularly preferably 2 to 15 parts by mass.

[0190] <Method for preparing curable resin composition>

[0191] The curable resin composition of the present embodiment is a negative curable resin comprising an alkali-soluble resin (A), a (meth)acrylic monomer (B), and a photopolymerization initiator (C), and can be prepared by adding a solvent, a polymerization inhibitor, a silane coupling agent, etc. and stirring and mixing.

[0192] (Solvent)

[0193] In the present embodiment, the solvent can be appropriately selected from known solvents according to the intended purpose.

[0194] Examples of the solvent include cyclohexanone, cyclopentanone, diethylene glycol methyl ethyl ether, acetylacetone, methanol, ethanol, ethyl cellosolve, ethyl cellosolve acetate, methyl cellosolve, methyl cellosolve acetate, diethylene glycol dimethyl ether, cyclohexanone, ethylbenzene, xylene, isoamyl acetate, n-amyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, diethylene glycol, diethylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and propylene glycol monomethyl ether acetate. Methyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol ethyl methyl ether (EDM), diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether, triethylene glycol monoethyl ether acetate, liquid polyethylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoethyl ether acetate, lactic acid ester, methyl methoxypropionate, ethyl ethoxypropionate, etc.

[0195] The above solvents may be used alone or in combination of two or more.

[0196] In addition, the content of the solvent in the curable resin composition of the present embodiment is not particularly limited. For example, from the viewpoint of storage stability and coating properties, it is preferred to use the solvent in a manner where the total solid content (the total mass of the components in the composition excluding the solvent) concentration is preferably 1 to 40 mass %, more preferably 5 to 40 mass %, and particularly preferably 10 to 30 mass %. By making the solid content ratio within the above range, the viscosity of the curable resin composition can be appropriately made, and the coating properties when applied to a substrate or the like to form a film are particularly improved.

[0197] (Inhibitor)

[0198] The curable resin composition of the present embodiment may contain a polymerization inhibitor from the viewpoint of suppressing the polymerization of the (meth)acrylic monomer (B) etc. As the polymerization inhibitor, a known ultraviolet absorber may be used.

[0199] Examples of the polymerization inhibitor include phenolic compounds such as 4-methoxyphenol, 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-N,N-dimethylamino-p-cresol, 2,4-dimethyl-6-tert-butylphenol, 4-tert-butylcatechol, 4,4'-thio-bis(3-methyl-6-tert-butylphenol), and 4,4'-butylene-bis(3-methyl-6-tert-butylphenol); 4-hydroxy-2,2,6,6-tetramethylpiperidinyl-N-oxyl free radical, 4-acetylamino-2,2,6,6-tetramethylpiperidinyl-N-oxyl free radical, 4-benzoyloxy-2,2,6,6-tetramethylpiperidinyl-N-oxyl free radical, 4-oxo-2,2,6,6-tetramethylpiperidinyl-N-oxyl free radical, and 4-oxo-2,2,6,6-tetramethylpiperidinyl-N-oxyl free radical. N-oxyl radical compounds such as tetramethylpiperidine-N-oxyl radical and 2,2,6,6-tetramethylpiperidine-N-oxyl radical; quinone compounds such as p-methoxyphenol (MEHQ), hydroquinone, 2,5-di-tert-butylhydroquinone, 2,6-di-tert-butylhydroquinone, and benzoquinone; cuprous chloride; dialkyldithiocarbamate copper such as dimethyldithiocarbamate; amino compounds such as phenothiazine, N,N'-diphenyl-p-phenylenediamine, phenyl-β-naphthylamine, N,N'-di-β-naphthyl-p-phenylenediamine, and N-phenyl-N'-isopropyl-p-phenylenediamine; hydroxylamine compounds such as 1,4-dihydroxy-2,2,6,6-tetramethylpiperidine, 1-hydroxy-2,2,6,6-tetramethylpiperidine, and 4-hydroxy-2,2,6,6-tetramethylpiperidine. As the polymerization inhibitor, for example, the above-mentioned p-methoxyphenol can be appropriately used. As the polymerization inhibitor, these may be used alone or in combination of two or more.

[0200] The amount of the polymerization inhibitor in the curable resin composition of the present embodiment is not particularly limited, but is preferably 0.1 to 0.6% by mass, more preferably 0.1 to 0.4% by mass, relative to the total solid content (the total mass of the components excluding the solvent in the composition) from the viewpoint of through-hole processability.

[0201] (Silane coupling agent)

[0202] The curable resin composition of the present embodiment may contain a silane coupling agent from the viewpoint of improving the adhesion between the substrate and the coating film. In addition, if the curable resin composition of the present embodiment contains a silane coupling agent, the insulating properties of the obtained cured product can be improved.

[0203] The type of the silane coupling agent is not particularly limited, and a known silane coupling agent can be used. For example, the following compounds can be used.

[0204]

[0205] The amount of the silane coupling agent in the curable resin composition of the present embodiment is not particularly limited, but is preferably 1 to 40 parts by mass, more preferably 5 to 30 parts by mass, relative to 100 parts by mass of the total amount of the alkali-soluble resin (A), from the viewpoint of improving adhesion to the substrate and insulation properties.

[0206] In addition, the curable resin composition of the present embodiment may also use various additives such as other inorganic fine particles, adhesion promoting additives, surfactants, storage stabilizers, leveling agents, light stabilizers, antioxidants, etc. as needed. As examples of these additives, for example, the additives described in Japanese Patent Application Laid-Open No. 2012-215833 can be cited.

[0207] 《Insulating Cured Film》

[0208] The application of the curable resin composition of the present embodiment is not particularly limited, and can be used for the purpose of forming an insulating film, for example, it can be used as an insulating cured film, especially an insulating cured film for a touch panel. The insulating cured film for a touch panel can be formed by the following operation: using various imparting methods such as spin coating such as spin coating, cast coating such as die coating, coating based on roll coating, coating based on roll transfer method, etc. to form a coating film on a substrate such as a glass substrate, ITO, a metal film, an organic film, etc., and curing the coating film.

[0209] Specifically, the cured film of the present embodiment can be formed by applying the curable resin composition on a base material such as a glass substrate, irradiating light through a mask, developing, and then, if necessary, performing a heat treatment to perform patterning.

[0210] The insulating cured film can be used for any application such as an insulating film application, a protective film application, a flat film application, etc. The insulating cured film using the curable resin composition of this embodiment can be particularly suitably used as a touch panel protective film or a touch panel insulating film.

[0211] The insulating cured film of the present embodiment can be used not only as a so-called permanent film maintained in a device such as a touch panel, but also as a resist film used when patterning an ITO film on a glass substrate.

[0212] (Through hole)

[0213] For purposes such as conduction between electrodes, a cured film used in an insulating cured film of a touch panel may be provided with through holes of a desired size. A through hole is a pattern formed by patterning. As described above, although the curable resin composition of the present embodiment is a negative composition, it has excellent through-hole processability and can form a through hole that is fully open to the side of the hole and has a hole cross-sectional shape that is an inverted trapezoidal shape when viewed from the exposure direction, and therefore can be used as a composition for forming a cured film with a through hole.

[0214] There is no particular limitation on the method for preparing a cured film with through holes using the curable resin composition of the present embodiment, and a known through-hole forming method and a method for preparing a cured film can be appropriately selected. As an example of a method for preparing a cured film with through holes using the curable resin composition of the present embodiment, there can be cited a method including the following steps: a step of forming a coating film by applying the curable resin composition of the present embodiment to a substrate (coating film forming step), a step of exposing the above-mentioned coating film through a through-hole forming mask (exposure step), a step of removing the non-exposed portion of the above-mentioned coating film after exposure with a developer (development step), and a step of heating the above-mentioned coating film with the non-exposed portion removed (for example, 90 to 230° C., 10 to 60 minutes) (post-baking step). Between the coating film forming step and the exposure step, etc., a step of heating the coating film (for example, 80 to 100° C., 60 to 180 seconds) (pre-baking step) can be implemented.

[0215] The non-exposure part (non-cured part) of the curable resin composition of the present embodiment is excellent in developability, and the developer resistance of the exposure part (cured part) is high. Therefore, it is possible to suppress overdevelopment, and it is possible to form a desired fine pattern. In addition, since a thermosetting resin (alkali-soluble resin (A1)) is also included in addition to a photocurable resin (alkali-soluble resin (A2)), the through-hole wall surface will not collapse in the post-baking process and the cone angle of the hole cross-sectional shape can be maintained. In this way, if the curable resin composition of the present embodiment is used, even if it is a through hole with a small pore size (for example, an pore size of less than 5 μm in diameter), it is possible to form a through hole that is fully open to the side of the hole and the hole cross-sectional shape is observed as an inverted trapezoid from the exposure direction.

[0216] The thickness of the cured film with through holes can be appropriately set depending on the purpose, and for example, from the viewpoint of reactivity, it may be 0.2 μm to 10 μm, or further may be 0.5 μm to 5 μm.

[0217] The pore size of the through-hole formed in the cured film with through-holes can be appropriately set according to the purpose, and for example, from the viewpoint of reactivity and developability, it can be 100 μm or less, and further can be 10 μm or less. Figure 3 As shown, the "aperture diameter" of the through hole formed in the cured film with through holes can be defined as the aperture diameter at a height equivalent to 10% of the height from the bottom surface of the through hole ( Figure 3 10% bottom CD in the 10 ”).

[0218] Cured film thickness 〔T〕 and opening diameter 〔R 10 〕(The hole diameter at a height equivalent to 10% of the height from the bottom of the through hole ( Figure 3 The ratio of 10% bottom CD)〔T:R 10 〕It is preferably 1:10 or less, and more preferably 1:1 to 4.

[0219] The opening size of the through hole formed in the cured film with through holes is not particularly limited, and is calculated by subtracting the hole diameter (R) of the through hole from the mask size (opening diameter (diameter) of the mask; for example, the opening diameter is 5 μm)). 10 ; 10% bottom CD value) is preferably less than 1.5 μm, and more preferably less than 0.5 μm.

[0220] For the taper angle of the cross-sectional shape of the through hole ( Figure 3 The angle α (cone angle) of the intersection of straight lines A and B shown is preferably less than 90°, and more preferably 15 to 70°, when metal wiring is formed on the upper layer of the insulating film so that the metal wiring will not be broken from the upper layer of the insulating film to the bottom of the through hole.

[0221] Touch Panel

[0222] As described above, the curable resin composition of the present embodiment and the insulating cured film using the same can be suitably used as an insulating film for touch panels. Hereinafter, the insulating cured film of the present embodiment and the insulating film for touch panels may be simply collectively referred to as “the cured film of the present embodiment”.

[0223] The touch panel of the present embodiment may be any one of a resistive film type, a capacitive type, an ultrasonic type, and an optical type, and is preferably a capacitive type touch panel.

[0224] Capacitive touch panels, for example, use glass with an ITO film as a substrate, and in order to prevent misidentification of the contact position, an insulating film and a protective film are provided in the laminated structure (for example, between electrodes). When the touch panel of this embodiment is a capacitive touch panel, the touch panel of this embodiment can use the cured film of this embodiment, for example, as an insulating film, a protective film, or both in the laminated structure.

[0225] In addition, the touch panel can be divided into a double-sided structure in which an X electrode is arranged on one side of the insulating film and a Y electrode is arranged on the other side, and a single-sided structure in which the X electrode and the Y electrode are formed on the same plane. The touch panel of this embodiment can be either a double-sided structure or a single-sided structure, and a touch panel of a single-sided structure is particularly preferred.

[0226] In the single-sided touch panel structure, the X electrode is electrically separated from the Y electrode. At this time, according to the pattern of the electrode, for example, it can be divided into an island pattern, a through-hole pattern, etc. For example, in the case of an island pattern, in addition, in the single-sided touch panel structure, the separated electrodes are electrically connected to each other by a component such as a jumper. In addition, the electrode jumper uses a transparent electrode such as an ITO film, but in the case where the separated Y electrodes are combined with each other in the jumper, for example, in order to maintain insulation from the X electrode, an insulating layer is provided at the bottom of the jumper. In addition, usually, an insulating film (protective film) is uniformly formed on each electrode arranged on the single-sided type.

[0227] Therefore, when the touch panel of this embodiment has a single-sided touch panel structure, the touch panel of this embodiment can use the cured film of this embodiment for example as an insulating film formed on the electrode, an insulating layer formed under the jumper part, or both.

[0228] Furthermore, when the touch panel is installed in a liquid crystal display device, it can be divided into an external embedded structure, a surface embedded structure, and an embedded structure according to its installation location. In the surface embedded structure and the embedded structure, the touch panel is installed in the liquid crystal panel, and in the external embedded structure, the touch panel is installed on the outside of the liquid crystal panel. In the surface embedded structure, the touch panel is arranged between the polarizer on the viewing direction side and the liquid crystal laminate (a laminate composed of a pair of substrate glasses and a liquid crystal layer interposed therebetween). In addition, in the embedded structure, the liquid crystal layer of the liquid crystal laminate has a touch panel function. The touch panel of this embodiment can be applied in any structure, but is preferably used in, for example, a surface embedded structure.

[0229] Hereinafter, one aspect of the touch panel according to the present embodiment will be described using drawings. Figure 1 FIG. 1 is a top view showing a configuration of a touch panel according to the present embodiment. Figure 1 As shown, when the touch panel of the present embodiment is a single-sided touch panel, ITO (indium tin oxide) electrodes ( X1 to X3 , Y1 to Y3 ) are formed on the glass substrate 10 .

[0230] The material of the glass substrate 10 is not particularly limited, and for example, a glass plate of soda-lime glass, low-alkali borosilicate glass, alkali-free aluminoborosilicate glass, etc. can be used. In addition, a plastic plate or plastic film made of polyethylene terephthalate (PET), triacetylcellulose (TAC), polymethyl methacrylate (PMMA), polycarbonate (PC), etc. can be used instead of the glass substrate.

[0231] ITO electrodes (X1 to X3, Y1 to Y3) are transparent electrodes. In the present embodiment, ITO is used as the material of the transparent electrode, but as long as it can be disposed on the surface of the substrate, there is no particular limitation. In addition to ITO, for example, inorganic conductive materials such as ZnO (zinc oxide), organic conductive materials such as PEDOT / PSS (polyethylene dioxythiophene / polystyrene sulfonic acid), polyaniline, and polypyrrole may also be used. Only one of these materials may be used, or two or more of them may be used in combination.

[0232] It should be noted that although Figure 1 and 2 Although the description is omitted in the figure, in each electrode and jumper portion X12, a metal thin film having a function as a metal wiring can be used as its lower layer or in place of the transparent electrode. The metal thin film can be made of metal materials such as Mo (molybdenum), Al (aluminum), Ag (silver), and Pd (palladium), and preferably one or more of Mo and Al are used.

[0233] like Figure 1 As shown, ITO electrodes X1 to X3 are Figure 1 The ITO electrodes X1 to X3 are arranged in the direction of the arrow P in FIG. 1 , and are separated from the adjacent electrodes, but are electrically connected to the adjacent electrodes in the direction of P via the jumper portion X12. The jumper portion X12 can be formed of the same material as the transparent electrode, such as ITO. In addition, at the lower part of the jumper portion X12 in the thickness direction, there is a Figure 2 The insulating film 14 is shown. Furthermore, in order to electrically connect the electrodes adjacent to each other in the P direction, through holes 20 are provided at both ends of each jumper portion X12.

[0234] In addition, ITO electrodes Y1 to Y3 are Figure 1 The electrodes are arranged in the direction of the arrow Q in FIG. The ITO electrodes Y1 to Y3 are continuously coupled to the electrodes adjacent in the Q direction via the connecting portions formed by the ITO film and are electrically connected in the Q direction. It should be noted that the ITO electrodes Y1 to Y3 are usually continuously formed as one with each connecting portion when the electrodes are formed.

[0235] Hereinafter, the electrode group electrically connected in the P direction is referred to as "X electrode", and the electrode group electrically connected in the Q direction is referred to as "Y electrode". Figure 1As shown, in a single-sided touch panel, the X electrodes are arranged along the P direction, and the Y electrodes are arranged along the Q direction.

[0236] Next use Figure 2 The cross-sectional structure of the touch panel according to the present embodiment will be described. Figure 2 yes Figure 1 AA cross-section diagram. Figure 2 As shown in FIG. 1 , an insulating film 14 and a connecting portion Y12 of the ITO electrodes Y1 and Y2 are interposed between the ITO electrodes X2 and X3. The ITO electrodes X2 and X3 are electrically connected by the jumper portion X12 as described above. In addition, a portion of the insulating film 14 extends between the jumper portion X12 and the connecting portion Y12 at the lower portion in the thickness direction to maintain the insulation between the jumper portion X12 and the connecting portion Y12. In addition, an insulating protective layer 16 is provided on the upper side of the insulating film 14 and the jumper portion X12 in the thickness direction.

[0237] In this embodiment, the cured film of this embodiment is used for at least one of the insulating film 14 and the insulating protective layer 16. However, the other may be formed using a known material conventionally used for the insulating film or the protective film, but it is preferred that both the insulating film 14 and the insulating protective layer 16 are the cured films of this embodiment.

[0238] In the above-mentioned touch panel, the method for forming the cured film of the present embodiment is not particularly limited. For example, a coating film can be formed on a lower layer (for example, a glass substrate 10 and an ITO electrode for an insulating film 14, or an ITO electrode for an insulating protective layer 16, etc.) by a coating method such as spraying, spin coating, slit die coating, roller coating, or rod coating. At this time, the dry film thickness of the coating film is not particularly limited. For example, in the case of an insulating protective layer 16, it is preferably 0.5 to 20 μm, and more preferably 1.0 to 10 μm. Similarly, in the case of an insulating film 14, the dry film thickness is preferably 0.2 to 10 μm, and more preferably 0.5 to 5 μm. In addition, as required, the coating film can be exposed by a mask having a prescribed pattern set in contact or non-contact with the coating film. The type of light during exposure is not particularly limited, and visible light, ultraviolet light, far infrared light, electron beam, X-ray, etc. can be cited, among which ultraviolet light is preferred. The illuminance of the light is not particularly limited, but is preferably 5 to 150 mW / cm at 365 nm. 2 , particularly preferably 5 to 35 mW / cm 2 .

[0239] Thereafter, the non-cured portion is removed by immersing in an aqueous alkaline developer such as sodium carbonate, sodium hydroxide, potassium hydroxide, or tetramethylammonium hydroxide (TMAH) as required, or spraying the developer by spraying, etc., to form a desired pattern. Furthermore, in order to promote the polymerization of the photosensitive composition and cure it, heating (post-baking) can be performed as required. It should be noted that when forming the cured film, the above-mentioned method for forming the through hole can be applied.

[0240] Furthermore, for example, when forming the jumper portion X12, first, patterned X electrodes and Y electrodes may be formed on the glass substrate 10, and then a curable resin composition may be applied to the glass substrate 10 and the electrode surface, and the curable resin composition may be exposed and developed using a mask capable of forming the insulating film 14 and the through hole 20. Next, a material (such as ITO) that will become the jumper portion X12 is deposited on the insulating film 14 and the through hole 20 by PVD or the like to form a conductive layer. Thereafter, only the portion where the jumper portion X12 is to be formed (for example, Figure 2 A protective layer is provided on the surface of the conductive layer of the insulating film 14 on the connection portion Y12, and an etching process is performed, thereby forming a jumper portion X12 on the insulating film 14 on the connection portion Y12.

[0241] Example

[0242] Hereinafter, the present invention will be described in more detail using Examples and Comparative Examples. The present invention is not limited to the following Examples in any way.

[0243] [Examples and Comparative Examples]

[0244] The components were mixed according to the formulation shown in the following table to prepare a curable resin composition. The mixing was performed at room temperature while shielding ultraviolet rays so as not to initiate a polymerization reaction.

[0245] [Table 1]

[0246]

[0247] ※In the table, "OXE-01" means Irgacure OXE01 (BASF JAPAN Co., Ltd.).

[0248] In addition, the numerical value about each component in a table|surface shows the mass part with respect to the whole composition (it does not include a solvent).

[0249] The components in the above table used were those shown in the table below.

[0250] [Table 2]

[0251]

[0252] [Table 3]

[0253]

[0254] [Table 4]

[0255]

[0256] [Table 5]

[0257]

[0258] "evaluate"

[0259] The curable compositions of the Examples and Comparative Examples obtained above were subjected to various evaluations. The results are shown in the following table.

[0260] (Determination of LogP)

[0261] LogP was measured under the following measurement conditions, using a reverse phase column (C18) and HPLC (high performance liquid chromatography) according to OECD GUIDELINES FOR THE TESTING CHEMICALS Partition Coefficient (n-octanol / water), High Performance Liquid Chromatography (HPLC) Method 117 (Adopted 13 April 2004). Benzyl alcohol, anisole, toluene, and butylbenzene were used as standard substances with known LogP.

[0262] [Measurement conditions]

[0263] · Apparatus: 1200 Series HPLC manufactured by Agilent Technology

[0264] Column: DiKMA Inspire C18 5 μm 150×4.6 mm

[0265] (particle size 5μm, inner diameter 4.6mm, length 150mm)

[0266] Mobile phase: A mixture of acetonitrile and 0.5 wt% phosphoric acid aqueous solution (mixing ratio 55:45)

[0267] Oven temperature: 40℃

[0268] Flow rate: 1mL / min

[0269] UV detection wavelength: 210nm

[0270] (Formation of through-hole)

[0271] The obtained curable resin composition was applied on a substrate having an ITO film by spin coating and pre-baked on a hot plate at 90°C for 90 seconds to form a coating film. Next, a contact hole pattern for a negative film (hole pitch 100 μm / hole diameter 5 μm) was used and the reaction mixture was heated at 40 mJ / cm 2 Irradiate with light from an ultra-high pressure mercury lamp (illuminance at 365 nm: 10 mW / cm 2 ). Next, the substrate was developed with a 2.38% TMAH aqueous solution for 30 seconds and heated at 90° C. for 30 minutes, thereby preparing a substrate with a cured film having a film thickness of 1.6 μm.

[0272] The cross section of the obtained cured film-attached substrate was observed with a laser microscope (manufactured by LASERTEC, product name: OPTELICS HYBRID), and each evaluation was performed based on the following criteria.

[0273] 〔Opening of through hole〕

[0274] A: The through hole penetrates to the substrate.

[0275] C: The membrane was confirmed at the bottom of the well, but no opening was observed.

[0276] 〔Opening size〕

[0277] For the substrate with the cured film in which the opening was confirmed, the hole diameter (R 10 ; 10% bottom CD value) (mask size (5μm) - R 10 (absolute value)) and evaluated according to the following criteria.

[0278] A: less than 0.5 μm

[0279] B: 0.5 μm or more and less than 1.5 μm

[0280] C: 1.5μm or more

[0281] 〔Conical〕

[0282] The cross section of the obtained substrate with the cured film was observed using a scanning electron microscope (manufactured by JEOL Ltd.; model: JSM-IT500) to measure Figure 3 The angle α (taper angle) of the intersection point of the straight lines A and B shown was evaluated according to the following criteria.

[0283] A: The cone angle is less than 90°.

[0284] C: The taper angle is 90° or more.

[0285] [Table 6]

[0286]

[0287] The obtained results show that although Comparative Example 1 which does not use the photocurable alkali-soluble resin (A2) of the present embodiment and Comparative Example 2 which does not use the thermosetting alkali-soluble resin (A1) of the present embodiment have through holes, the opening size is small and the processability is poor.

[0288] In addition, in Comparative Examples 3 to 6 in which the (meth)acrylic monomer (B) of the present embodiment was not used, in Comparative Example 7 in which the mass ratio [A:B] of the total amount [A] of the thermosetting alkali-soluble resin (A1) and the photocurable alkali-soluble resin (A2) to the total amount [B] of the above-mentioned (meth)acrylic monomer (B) was 100:30, and in Comparative Example 8 in which a resin having an acid value of less than 55 mgKOH / g was used, the through holes did not penetrate to the substrate.

[0289] In contrast, the through-hole penetration of the example using the curable composition of the present embodiment was excellent in any evaluation of the opening size, the film thickness: opening diameter ratio, and the taper. Therefore, it can be seen that the curable composition of the example has excellent through-hole processability and can form a through-hole of about 4 μm for a film thickness of about 1.6 μm.

[0290] The disclosed contents of Japanese Patent Application No. 2022-106883 filed on July 1, 2022 are incorporated into this specification by reference in their entirety.

[0291] In addition, all documents, patent applications, and technical standards described in the specification are incorporated herein by reference to the same extent as if each document, patent application, and technical standard was specifically and individually described as being incorporated by reference.

[0292] Explanation of symbols

[0293] 10: Glass substrate, 14: Insulating film, 16: Insulating protective layer, X1~X3, Y1~Y4: ITO electrodes, X12: Jumper part, Y12: Connecting part, 20: Through hole

Claims

1. A curable resin composition comprising: Thermosetting alkali-soluble resin A1 having an acid value of 55 to 100 mgKOH / g, Photocurable alkali-soluble resin A2, a (meth)acrylic monomer B having two polymerizable functional groups and a ring structure contained between the two polymerizable functional groups, and Photopolymerization initiator C; The mass ratio A:B of the total amount A of the thermosetting alkali-soluble resin A1 and the photocurable alkali-soluble resin A2 to the total amount B of the (meth)acrylic monomer B is 100:35-80.

2. The curable resin composition according to claim 1, wherein The thermosetting alkali-soluble resin A1 has an acid group and a cyclic ether group.

3. The curable resin composition according to claim 1, wherein The thermosetting alkali-soluble resin A1 contains at least the following units (a1-1) and (a1-2), In unit (a1-1), R 1 represents a hydrogen atom or a methyl group, X 1 represents a single bond, or a linear or cyclic aliphatic hydrocarbon group having 1 to 15 carbon atoms which may contain an oxygen atom. In the unit (a1-2), R 1 represents a hydrogen atom or a methyl group, R 3 It represents a linear or branched aliphatic hydrocarbon group having 3 to 15 carbon atoms which has a cyclic ether structure and may contain an oxygen atom.

4. The curable resin composition according to claim 3, wherein The thermosetting alkali-soluble resin A1 further comprises the following unit (a1-3), In the formula, R 1 represents a hydrogen atom or a methyl group, R 4 It represents at least one selected from a linear, branched or cyclic aliphatic hydrocarbon group having 1 to 20 carbon atoms which may contain an oxygen atom, an aromatic group, and a combination thereof.

5. The curable resin composition according to claim 1, wherein The acid value of the photocurable alkali-soluble resin A2 is 70 mgKOH / g or less.

6. The curable resin composition according to claim 1, wherein The photocurable alkali-soluble resin A2 contains at least the following units (a2-1) and (a2-2), In unit (a2-1), R 1 Each independently represents a hydrogen atom or a methyl group, R 5 represents a chain, branched or cyclic aliphatic hydrocarbon group having 2 to 15 carbon atoms which may contain a hetero atom. In the unit (a2-2), R 1 represents a hydrogen atom or a methyl group, X 1 It represents a single bond or a linear or cyclic aliphatic hydrocarbon group having 1 to 15 carbon atoms which may contain an oxygen atom.

7. The curable resin composition according to claim 6, wherein The photocurable alkali-soluble resin A2 further comprises the following unit (a2-3), In the formula, R 1 represents a hydrogen atom or a methyl group, R 4 It represents at least one selected from a linear, branched or cyclic aliphatic hydrocarbon group having 1 to 20 carbon atoms which may contain an oxygen atom, an aromatic group, and a combination thereof.

8. The curable resin composition according to claim 1, wherein The weight average molecular weight of the photocurable alkali-soluble resin A2 is 20,000 or less.

9. The curable resin composition according to claim 1, wherein At least one of the thermosetting alkali-soluble resin A1 and the photocurable alkali-soluble resin A2 has a cyclic group.

10. The curable resin composition according to claim 1, wherein The ring structure in the (meth)acrylic monomer B is any one selected from an aliphatic hydrocarbon group having 6 to 26 carbon atoms which may contain an oxygen atom, an aromatic hydrocarbon group having 6 to 26 carbon atoms which may contain an oxygen atom, and a combination thereof.

11. The curable resin composition according to claim 1, wherein The two polymerizable functional groups in the (meth)acrylic monomer B include an acryloyl group.

12. The curable resin composition according to claim 1, wherein The (meth)acrylic monomer B is a compound represented by the following formula (b1): In the formula, R 11 and R 12 Each independently represents a hydrogen atom or a methyl group, Y 1 and Y 2 Each independently represents a single bond, or a linear or branched aliphatic hydrocarbon group having 1 to 26 carbon atoms which may contain an oxygen atom, and X 11 W1 represents an aliphatic hydrocarbon group or an aromatic group having 6 to 26 carbon atoms and a cyclic skeleton, and W1 and W2 each independently represent O, N or S. 13 . The curable resin composition according to claim 1 , which is used for forming an insulating film. 14 . An insulating cured film obtained by curing the curable resin composition according to claim 1 . 15 . An insulating cured film for a touch panel, which is obtained by curing the curable resin composition according to claim 1 . 16 . A touch panel comprising the insulating cured film for a touch panel according to claim 15 .

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