Photosensitive composition, transparent cured film, laminate, and method for producing laminate

Abstract

To provide a photosensitive composition which can achieve high resolution and excellent curability while having high transparency.SOLUTION: A photosensitive composition contains a photosensitive resin (A), a photopolymerization initiator (B) and a photopolymerizable compound (C). The photosensitive resin (A) contains a photosensitive resin (A1) which is produced by reaction of a product produced by reaction of an epoxy compound (a1) having at least two epoxy groups and carboxylic acid (a2) having an ethylenically unsaturated group, and acid anhydride (a3) containing acid dianhydride (a4). When a dry film having a thickness dimension of 10 μm is prepared from the photosensitive composition, light transmittance at a wavelength of 450-800 nm is 85% or more, a maximum value of absorbance in a wavelength region of 250-800 nm of the dry film is in a wavelength region of 300-330 nm, and a maximum value of the absorbance is 1 or larger.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a photosensitive composition, a transparent cured film containing a cured product of the photosensitive composition, a laminate containing the transparent cured film, and a method for producing the laminate.

Background Art

[0002] In Patent Document 1, a photosensitive resin composition containing a binder polymer having a specific acid value, a photopolymerizable compound, and a photopolymerization initiator having a specific structure is disclosed as a photosensitive resin composition for forming a protective film formed on an electrode for a touch panel. This photosensitive resin composition can form a resin cured film pattern with sufficient resolution even in a thin film, and further improves the resolution by using an ultraviolet absorber in combination.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, although the photosensitive resin composition of Patent Document 1 improves the resolution by using an ultraviolet absorber in combination, there is a concern that the transparency and curability may decrease, and it is not easy to satisfy the transparency and curability while having a high resolution. In addition, there is a concern about the precipitation of the ultraviolet absorber and the bleed-out due to long-term use.

[0005] An object of the present invention is to provide a photosensitive composition having high transparency and resolution, a transparent cured film containing a cured product of the photosensitive composition, a laminate containing the transparent cured film, and a method for producing the laminate.

Means for Solving the Problems

[0006] The photosensitive composition according to one aspect of the present invention contains a photosensitive resin (A) containing a resin having an ethylenically unsaturated group and a carboxyl group, a photopolymerization initiator (B), and a photopolymerizable compound (C). The photosensitive resin (A) contains a photosensitive resin (A1) formed by reacting an epoxy compound (a1) having at least two epoxy groups with a carboxylic acid (a2) having an ethylenically unsaturated group and then reacting the resulting product with an acid anhydride (a3) containing an acid dianhydride (a4). The number average molecular weight Mn of the photosensitive resin (A1) is 500 or more and 2500 or less, the polydispersity Mw / Mn is 1.2 or more and 2.8 or less, and the acid value is 55 mgKOH / g or more and 130 mgKOH / g or less. When a dry film having a thickness dimension of 10 μm is produced from the photosensitive composition, the light transmittance at a wavelength of 450 to 800 nm is 85% or more, the maximum value of the absorbance of the dry film in the wavelength range of 250 to 800 nm is in the wavelength range of 300 to 330 nm, and the maximum value of the absorbance is 1 or more.

[0007] The transparent cured film according to one aspect of the present invention includes a cured product of the photosensitive composition.

[0008] The laminate according to one aspect of the present invention includes a base material and the transparent cured film overlapping the base material.

[0009] The method for manufacturing a laminate according to one aspect of the present invention includes producing a dry film having a thickness dimension of 10 μm or less by applying the photosensitive composition on a base material, partially exposing the dry film, and then developing with an alkaline developer to form a pattern, thereby producing a transparent cured film overlapping the base material.

Effects of the Invention

[0010] According to the photosensitive composition, transparent cured film, and laminate of one aspect of the present invention, high transparency, high resolution, and excellent curability can be achieved.

[0011] According to the method for manufacturing a laminate of one aspect of the present invention, a laminate having high transparency suitable for optical applications can be obtained.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments for carrying out the present invention will be described. In the following description, “(meth)acrylic” means at least one of “acrylic” and “methacrylic”. For example, (meth)acrylate means at least one of acrylate and methacrylate.

[0014] The photosensitive composition of the present embodiment contains a photosensitive resin (A) containing a resin having an ethylenically unsaturated group and a carboxyl group, a photopolymerization initiator (B), and a photopolymerizable compound (C). The photosensitive resin (A) contains a product formed by reacting an epoxy compound (a1) having at least two epoxy groups and a carboxylic acid (a2) having an ethylenically unsaturated group, and a photosensitive resin (A1) formed by reacting an acid anhydride (a3) containing an acid dianhydride (a4). The number average molecular weight Mn of the photosensitive resin (A1) is 500 or more and 2500 or less, the polydispersity Mw / Mn is 1.2 or more and 2.8 or less, and the acid value is 55 mgKOH / g or more and 130 mgKOH / g or less. When a dry film having a thickness dimension of 10 μm is produced from the photosensitive composition, the light transmittance at a wavelength of 450 to 800 nm is 85% or more. The maximum value of the absorbance in the wavelength range of 250 to 800 nm of the dry film is in the wavelength range of 300 to 330 nm, and the maximum value of the absorbance is 1 or more.

[0015] Since the photosensitive resin (A) has an ethylenically unsaturated group and a carboxyl group, the photosensitive composition has photosensitivity and can be developed using an alkaline solution or the like. Further, when the number average molecular weight Mn of the photosensitive resin (A) is 500 or more and 2500 or less, and the polydispersity Mw / Mn is 1.2 or more and 2.8 or less, tack hardly occurs in the dry film formed from the photosensitive composition, and the insulation reliability and plating resistance of the cured product of the photosensitive composition are hardly impaired. Furthermore, the photosensitive composition can have excellent developability. That is, when the polydispersity Mw / Mn of the photosensitive composition is 1.2 or more and the number average molecular weight Mn is 500 or more, tack hardly occurs in the dry film, and the insulation reliability and plating resistance are hardly impaired. When the polydispersity Mw / Mn is 2.8 or less and the number average molecular weight Mn is 2500 or less, the developability with an alkaline aqueous solution is likely to be improved.

[0016] Furthermore, when the acid value of the photosensitive resin (A) is 55 mgKOH / g or more and 130 mgKOH / g or less, the resolution of the cured product formed from the photosensitive composition is particularly likely to be improved.

[0017] When a dry film having a thickness dimension of 10 μm is produced from the photosensitive composition, a cured film with high transparency can be produced because the light transmittance at wavelengths of 450 to 800 nm is 85% or more. Further, the maximum value of the absorbance in the wavelength range of 250 to 800 nm in the dry film is in the wavelength range of 300 to 330 nm, and the maximum value of the absorbance is 1 or more, so that the resolution is more likely to be improved. The reason is presumed as follows. Light in the wavelength range of 300 to 330 nm in ultraviolet light hardly reaches the bottom (deep part) in the dry film containing organic substances, and when the energy of the light in the wavelength range (300 to 330 nm) is used for the photocuring of the dry film, the resolution is likely to decrease. However, when the maximum value of the absorbance of the dry film of the photosensitive composition of the present embodiment is in the wavelength range of 300 to 330 nm, the photosensitive resin (A) absorbs the light in the wavelength range (300 to 330 nm) and it becomes difficult to be used for photocuring, so that the resolution of the cured product is less likely to decrease. Moreover, in the present embodiment, since the absorption of visible light by the dry film is small, the transparency is not impaired, and since the light having a wavelength longer than the wavelength of the maximum value of the absorbance of the dry film can be used for the curing reaction, the curability of the photosensitive composition is less likely to be inhibited.

[0018] As described above, the cured product produced from the photosensitive composition according to the present embodiment can improve the resolution while maintaining the transparency and curability.

[0019] The components that the photosensitive composition according to the present embodiment may contain will be described in detail.

[0020] As described above, the photosensitive resin (A) contains the photosensitive resin (A1). The synthesis of the photosensitive resin (A1) will be described.

[0021] The product formed by the reaction of the epoxy compound (a1) and the carboxylic acid (a2) (hereinafter also referred to as "product (X)") contains the product (X1) formed by the reaction of each of the two epoxy groups in the epoxy compound (a1) with the carboxyl group in the carboxylic acid (a2). This product (X1) has a secondary hydroxyl group generated by the reaction of the epoxy group and the carboxyl group, and an ethylenically unsaturated group derived from the carboxylic acid (a2). The product (X) may also contain the product (X2) formed by the reaction of only one of the two epoxy groups in the epoxy compound (a1) with the carboxyl group in the carboxylic acid (a2). The product (X2) has a secondary hydroxyl group, an ethylenically unsaturated group, and an epoxy group. The product (X) may also contain the unreacted epoxy compound (a1). That is, the product (X) may contain a component having an epoxy group, and this component may include at least one of the product (X2) and the epoxy compound (a1).

[0022] The photosensitive resin (A1) formed by the reaction of the product (X) and the acid anhydride (a3) contains the component (X3) formed by the reaction of the product (X1) and the acid dianhydride (a4). The component (X3) has a carboxyl group derived from the acid dianhydride (a4). Also, since a crosslinking reaction by the acid dianhydride (a4) may occur, the component (X3) is likely to have a molecular weight distribution. The photosensitive resin (A1) may also contain the unreacted product (X1).

[0023] Furthermore, the acid anhydride (a3) may contain the monoacid anhydride (a5). Therefore, the photosensitive resin (A1) formed by the reaction of the product (X) and the acid anhydride (a3) contains the component (X4) formed by the reaction of the product (X1) and the monoacid anhydride (a5). The component (X4) has a carboxyl group derived from the monoacid anhydride (a5).

[0024] As a result, the photosensitive resin (A1) can have a suitable molecular weight distribution. Therefore, a photosensitive resin (A1) having a desired molecular weight and polydispersity can be easily obtained. That is, a photosensitive resin (A1) is obtained in which the number average molecular weight Mn is 500 or more and 2500 or less, and the polydispersity Mw / Mn is in the range of 1.2 or more and 2.8 or less.

[0025] The photosensitive resin (A) preferably contains a resin having an epoxy group. When the photosensitive resin (A) contains a resin having an epoxy group, it can have reactivity with the remaining carboxyl groups in the photosensitive composition. Therefore, the photosensitive composition can exhibit thermosetting properties.

[0026] Since the photosensitive resin (A1) has an ethylenically unsaturated group derived from a carboxylic acid (a2) having an ethylenically unsaturated group, it has photoreactivity. Therefore, the photosensitive resin (A1) can impart photosensitivity (specifically, ultraviolet curability) to the photosensitive composition. Further, since the photosensitive resin (A1) has a carboxyl group derived from an acid anhydride (a3), it can impart developability with an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide to the photosensitive composition. Furthermore, when the acid anhydride (a3) contains an acid dianhydride (a4), the molecular weight of the photosensitive resin (A1) depends on the number of crosslinks by the acid dianhydride (a4). Therefore, a photosensitive resin (A1) with appropriately adjusted acid value and molecular weight can be obtained. Also, when the acid anhydride (a3) contains an acid dianhydride (a4), a photosensitive resin (A1) with a desired molecular weight and acid value can be easily obtained by controlling the amount of the acid dianhydride (a4).

[0027] The number average molecular weight of the photosensitive resin (A1) is preferably 500 or more and 2500 or less. In this case, the developability of the photosensitive composition with an alkaline aqueous solution is likely to be improved. The number average molecular weight is more preferably 800 or more and 2300 or less, still more preferably 900 or more and 2200 or less, and particularly preferably 1000 or more and 2000 or less.

[0028] The polydispersity Mw / Mn of the photosensitive resin (A1) is preferably 1.2 or more and 2.8 or less. The polydispersity Mw / Mn of the photosensitive resin (A1) is more preferably 1.3 or more and 2.7 or less, still more preferably 1.4 or more and 2.6 or less, and particularly preferably 1.5 or more and 2.5 or less. The polydispersity is the value (Mw / Mn) of the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the photosensitive resin (A1).

[0029] The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the photosensitive resin (A1) are calculated from the results of molecular weight measurement by gel permeation chromatography. The molecular weight measurement by gel permeation chromatography can be carried out, for example, under the following conditions.

[0030] GPC apparatus: SHODEX SYSTEM 11 manufactured by Showa Denko KK, Columns: Four columns of SHODEX KF-800P, KF-005, KF-003, and KF-001 in series, Mobile phase: THF, Flow rate: 1 ml / min, Column temperature: 45 °C, Detector: RI, Conversion: Polystyrene.

[0031] The acid value of the photosensitive resin (A1) is preferably 55 mgKOH / g or more and 130 mgKOH / g or less. In this case, the resolution of the cured product produced from the photosensitive composition is particularly improved. The acid value of the photosensitive resin (A1) is more preferably 60 mgKOH / g or more and 120 mgKOH / g or less, still more preferably 60 mgKOH / g or more and 110 mgKOH / g or less, and particularly preferably 60 mgKOH / g or more and less than 75 mgKOH / g.

[0032] The raw materials of the photosensitive resin (A1) and the reaction conditions during the synthesis of the photosensitive resin (A1) will be described in detail.

[0033] The epoxy compound (a1) having at least two epoxy groups can contain, for example, a compound having a bisphenol fluorene skeleton. The photosensitive resin (A1) is, for example, a reaction product of an epoxy compound having a bisphenol fluorene skeleton represented by the following formula (1) and a carboxylic acid (a2) having an ethylenically unsaturated group, and an acid anhydride (a3). That is, the photosensitive resin (A1) is synthesized by reacting an epoxy compound having a bisphenol fluorene skeleton represented by the following formula (1) with a carboxylic acid (a2) having an ethylenically unsaturated group, and then reacting the resulting product with an acid anhydride (a3). When the photosensitive composition contains the photosensitive resin (A1), the cured product of the photosensitive composition can have high heat resistance and insulation reliability. Further, when the photosensitive resin (A1) has a bisphenol fluorene skeleton, since it easily absorbs light in the wavelength range of 300 to 330 nm, the resolution of the cured product produced from the photosensitive composition can be improved. Further, when the photosensitive resin (A1) has a bisphenol fluorene skeleton, since it has a bulky structure, it can prevent the diffusion of the generated radical species, and even when exposed to light having no wavelength range of 300 to 330 nm, the resolution of the cured product produced from the photosensitive composition can be improved.

[0034] [Chemical formula]

[0035] R in formula (1) 1 ~R 8 Each of them may be hydrogen, but may also be an alkyl group having 1 to 5 carbon atoms or a halogen. This is because even if the hydrogen in the aromatic ring is substituted with a low molecular weight alkyl group or halogen, it has no adverse effect on the physical properties of the carboxyl group-containing resin (A1), and rather, the heat resistance or flame retardancy of the cured product of the photosensitive composition containing the carboxyl group-containing resin (A1) may be improved.

[0036] The epoxy compound (a1) may have, for example, a structure represented by the following formula (2). n in formula (2) is an integer, for example, within the range of 0 to 20. In order to appropriately control the molecular weight of the carboxyl group-containing resin (A1), it is particularly preferable that the average of n is within the range of 0 to 1. If the average of n is within the range of 0 to 1, even when the acid anhydride (a3) contains an acid dianhydride, an excessive increase in molecular weight is likely to be suppressed. Further, in formula (2), R 1 ~R 8 are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or a halogen.

[0037]

Chemical formula

[0038] The carboxylic acid (a2) having an ethylenically unsaturated group may contain, for example, a compound having only 1 ethylenically unsaturated group in one molecule. More specifically, the carboxylic acid (a2) having an ethylenically unsaturated group may contain, for example, acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, crotonic acid, cinnamic acid, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl phthalic acid, 2-acryloyloxypropyl phthalic acid, 2-methacryloyloxypropyl phthalic acid, 2-acryloyloxyethyl maleic acid, 2-methacryloyloxyethyl maleic acid, β-carboxyethyl acrylate, 2-acryloyloxyethyl tetrahydrophthalic acid, 2-methacryloyloxyethyl tetrahydrophthalic acid, 2-acryloyloxyethyl hexahydrophthalic acid, and 2-methacryloyloxyethyl hexahydrophthalic acid. Preferably, the carboxylic acid (a2) having an ethylenically unsaturated group contains acrylic acid.

[0039] When reacting the epoxy compound (a1) with the carboxylic acid (a2), an appropriate method can be adopted. For example, the carboxylic acid (a2) is added to a solvent solution of the epoxy compound (a1), and further, a thermal polymerization inhibitor and a catalyst are added as necessary and stirred and mixed to obtain a reactive solution. By reacting this reactive solution by a conventional method, preferably at a temperature of 60°C or higher and 150°C or lower, particularly preferably 80°C or higher and 120°C or lower, the product (X) can be obtained. The solvent in this case can contain at least one component selected from the group consisting of ketones such as methyl ethyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene and xylene, acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, and propylene glycol monomethyl ether acetate, and dialkyl glycol ethers. The thermal polymerization inhibitor contains at least one of, for example, hydroquinone and hydroquinone monomethyl ether. The catalyst can contain at least one component selected from the group consisting of tertiary amines such as benzyldimethylamine and triethylamine, quaternary ammonium salts such as trimethylbenzylammonium chloride and methyltriethylammonium chloride, triphenylphosphine, and triphenylstibine.

[0040] It is particularly preferable that the catalyst contains triphenylphosphine. That is, in the presence of triphenylphosphine, it is preferable to react the epoxy compound (a1) with the carboxylic acid (a2). In this case, the ring-opening addition reaction between the epoxy group in the epoxy compound (a1) and the carboxylic acid (a2) is particularly promoted, and a reaction rate (conversion rate) of 95% or more, or 97% or more, or almost 100% can be achieved.

[0041] When reacting the epoxy compound (a1) with the carboxylic acid (a2), the amount of the carboxylic acid (a2) relative to 1 mol of the epoxy group of the epoxy compound (a1) is preferably 0.7 mol or more and 1.0 mol or less. In this case, a photosensitive composition having excellent photosensitivity and stability can be obtained.

[0042] The product (X) thus obtained has a hydroxyl group formed by the reaction of the epoxy group of the epoxy compound (a1) and the carboxyl group of the carboxylic acid (a2).

[0043] The acid dianhydride (a4) is a compound having two acid anhydride groups. The acid dianhydride (a4) can contain an anhydride of a tetracarboxylic acid. The acid dianhydride (a4) is, for example, 1,2,4,5-benzenetetracarboxylic dianhydride, benzophenonetetracarboxylic dianhydride, methylcyclohexenetetracarboxylic dianhydride, tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, ethylenetetracarboxylic dianhydride, 9,9'-bis(3,4-dicarboxyphenyl)fluorene dianhydride, glycerin bisanhydrotrimellitate monoacetate, ethylene glycol bisanhydrotrimellitate, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5(tetrahydro-2,5-dioxo-3-furanyl)naphtho[1,2-c]furan-1,3-dione, 1,2,3,4-butanetetracarboxylic dianhydride, and at least one compound selected from the group consisting of 3,3',4,4'-biphenyltetracarboxylic dianhydride. In particular, it is preferable that the acid dianhydride (a4) contains 3,3',4,4'-biphenyltetracarboxylic dianhydride. In this case, while ensuring good developability of the photosensitive composition, the tackiness of the film formed from the photosensitive composition can be further suppressed, and the insulation reliability and plating resistance of the cured product can be further improved.

[0044] The acid anhydride (a3) may contain a monoacid anhydride (a5). The monoacid anhydride (a5) is a compound having one acid anhydride group. The monoacid anhydride (a5) can contain a dicarboxylic acid anhydride. The monoacid anhydride (a5) can contain at least one compound selected from the group consisting of, for example, phthalic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride, methylsuccinic anhydride, maleic anhydride, citraconic anhydride, glutaric anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, and itaconic anhydride. In this case, while ensuring good developability of the photosensitive composition, the tackiness of the film formed from the photosensitive composition can be further suppressed, and the insulation reliability and plating resistance of the cured product can be further improved.

[0045] When reacting the product (X) with the acid anhydride (a3), an appropriate method can be adopted. For example, the acid anhydride (a3) is added to a solvent solution of the product (X), and if necessary, a thermal polymerization inhibitor and a catalyst are further added and stirred and mixed to obtain a reactive solution. This reactive solution is reacted by a conventional method, preferably at a temperature of 60°C or higher and 150°C or lower, particularly preferably 80°C or higher and 120°C or lower, to obtain the photosensitive resin (A1). As the solvent, catalyst, and polymerization inhibitor, appropriate ones can be used, and the solvent, catalyst, and polymerization inhibitor used during the synthesis of the product (X) can also be used as they are.

[0046] It is particularly preferable that the catalyst contains triphenylphosphine. That is, it is preferable to react the product (X) with the acid anhydride (a3) in the presence of triphenylphosphine. In this case, the reaction between the secondary hydroxyl group in the product (X) and the acid anhydride (a3) is particularly promoted, and a reaction rate (conversion rate) of 90% or more, 95% or more, 97% or more, or almost 100% can be achieved.

[0047] When the acid anhydride (a3) contains the diacid anhydride (a4), the amount of the diacid anhydride (a4) is preferably 0.01 mol or more and 0.24 mol or less with respect to 1 mol of the epoxy groups of the epoxy compound (a1). In this case, the photosensitive resin (A1) with appropriately adjusted acid value and molecular weight can be easily obtained. More preferably, the amount of the diacid anhydride (a4) is 0.04 mol or more and 0.22 mol or less.

[0048] Also, when the acid anhydride (a3) further contains the monoacid anhydride (a5), the amount of the monoacid anhydride (a5) is preferably 0.05 mol or more and 0.7 mol or less with respect to 1 mol of the epoxy groups of the epoxy compound (a1). In this case, the photosensitive resin (A1) with appropriately adjusted acid value and molecular weight can be easily obtained.

[0049] It is also preferable to react the product (X) with the acid anhydride (a3) under air bubbling. In this case, excessive molecular weight increase of the produced photosensitive resin (A1) is suppressed, and thus the developability of the photosensitive composition with an alkaline aqueous solution is particularly improved.

[0050] The components other than the photosensitive resin (A1) in the photosensitive composition will be described.

[0051] As described above, the photosensitive composition contains, for example, a photosensitive resin (A) containing a resin having an ethylenically unsaturated group and a carboxyl group, a photopolymerization initiator (B), and a photopolymerizable compound (C).

[0052] The photosensitive resin (A) may contain only the photosensitive resin (A1), or may contain a photosensitive resin (A2) other than the photosensitive resin (A1). The photosensitive resin (A2) contains, for example, a resin that is a reaction product of a polymer of an ethylenically unsaturated monomer containing an ethylenically unsaturated compound having a carboxyl group and an ethylenically unsaturated compound having an epoxy group. The ethylenically unsaturated monomer may further contain an ethylenically unsaturated compound having no carboxyl group. The photosensitive resin (A2) is obtained by reacting an ethylenically unsaturated compound having an epoxy group with a part of the carboxyl groups in the polymer. The ethylenically unsaturated monomer may further contain an ethylenically unsaturated compound having no carboxyl group. The ethylenically unsaturated compound having a carboxyl group contains compounds such as acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, pentaerythritol triacrylate, and pentaerythritol trimethacrylate. The ethylenically unsaturated compound having no carboxyl group contains compounds such as 2-(meth)acryloyloxyethyl phthalate, 2-(meth)acryloyloxyethyl-2-hydroxyethyl phthalate, and linear or branched aliphatic or alicyclic (wherein the ring may have a partial unsaturated bond) (meth)acrylic acid esters. The ethylenically unsaturated compound having an epoxy group preferably contains glycidyl (meth)acrylate.

[0053] The photoinitiator (B) is a component that can improve the photosensitivity of the photosensitive composition. The photoinitiator (B) preferably contains at least one selected from the group consisting of α-aminoalkylphenone-based photoinitiators, acylphosphine oxide-based photoinitiators, and oxime ester-based photoinitiators. In this case, when the photosensitive composition is irradiated with light such as ultraviolet light for exposure, high photosensitivity can be imparted to the photosensitive composition. The photoinitiator (B) more preferably contains an acylphosphine oxide-based photoinitiator. In this case, high photosensitivity can be imparted to the photosensitive composition, and there is less coloring and high transparency can be maintained.

[0054] The α-aminoalkylphenone-based photoinitiator can contain at least one component selected from the group consisting of, for example, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, and 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone.

[0055] The acylphosphine oxide-based photoinitiator can contain at least one component selected from the group consisting of, for example, monoacylphosphine oxide-based photoinitiators such as 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide and 2,4,6-trimethylbenzoyl-ethyl-phenyl-phosphinate, and bisacylphosphine oxide-based photoinitiators such as bis-(2,6-dichlorobenzoyl)phenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and (2,5,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0056] The oxime ester-based photoinitiator can contain at least one component selected from the group consisting of, for example, 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)] and ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetoxime).

[0057] The photosensitive composition may further contain a suitable photoinitiator, sensitizer, etc. For example, the photosensitive composition may contain hydroxyketones such as 1-hydroxy-cyclohexyl-phenyl-ketone, methyl phenylglyoxylate, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, and 2-hydroxy-2-methyl-1-phenyl-propan-1-one; benzoin and its alkyl ethers; acetophenones such as acetophenone and benzyldimethyl ketal; anthraquinones such as 2-methylanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, and 2,4-diisopropylthioxanthone; benzophenones such as benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, and bis(diethylamino)benzophenone; xanthones such as 2,4-diisopropylxanthone; and α-hydroxyketones such as 2-hydroxy-2-methyl-1-phenyl-propan-1-one; and may contain at least one component selected from the group consisting of compounds containing a nitrogen atom such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone. The photosensitive composition may, together with the photoinitiator (B), contain a suitable photoinitiator such as a tertiary amine-based compound like ethyl p-dimethylbenzoate, isoamyl p-dimethylaminobenzoate, and 2-dimethylaminoethyl benzoate, and a sensitizer, etc. The photosensitive composition may, if necessary, contain at least one of a photoinitiator for visible light exposure and a photoinitiator for near-infrared light exposure. The photosensitive adhesive composition may, together with the photoinitiator (B), contain a coumarin derivative such as 7-diethylamino-4-methylcoumarin, a carbocyanine dye-based compound, a xanthene dye-based compound, etc., which are sensitizers for laser exposure methods.

[0058] The photopolymerizable compound (C) can impart photocurability to the photosensitive composition. The photopolymerizable compound (C) preferably contains at least one selected from the group consisting of a photopolymerizable monomer and a photopolymerizable prepolymer. Examples of the photopolymerizable monomer include monofunctional (meth)acrylates such as 2-hydroxyethyl (meth)acrylate; and at least one compound selected from the group consisting of polyfunctional (meth)acrylates such as diethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ε-caprolactone-modified pentaerythritol hexaacrylate, and tricyclodecane dimethanol di(meth)acrylate.

[0059] The photopolymerizable prepolymer can contain at least one compound selected from the group consisting of, for example, a prepolymer obtained by polymerizing a monomer having an ethylenically unsaturated bond and then adding an ethylenically unsaturated group, and oligo(meth)acrylate prepolymers. The oligo(meth)acrylate prepolymers can contain at least one component selected from the group consisting of, for example, epoxy (meth)acrylate, polyester (meth)acrylate, urethane (meth)acrylate, alkyd resin (meth)acrylate, silicone resin (meth)acrylate, and spiran resin (meth)acrylate.

[0060] In particular, the photopolymerizable compound (C) preferably contains at least one of a bifunctional unsaturated compound and a trifunctional unsaturated compound, that is, at least one compound having two unsaturated bonds in one molecule or at least one compound having three unsaturated bonds in one molecule. In this case, the resolution when exposing and developing the dry film prepared from the photosensitive composition is improved, and the developability of the photosensitive composition with an alkaline aqueous solution is particularly improved.

[0061] The photosensitive composition preferably further contains an epoxy compound (D). In this case, thermosetting properties can be imparted to the photosensitive composition. Further, in this case, the plating resistance and insulation properties of the cured product produced from the photosensitive composition can be improved.

[0062] The epoxy compound (D) can contain, for example, a crystalline epoxy resin (D1). Further, the epoxy compound (D) may further contain an amorphous epoxy resin (D2). Here, the "crystalline epoxy resin" is an epoxy resin having a melting point, and the "amorphous epoxy resin" is an epoxy resin having no melting point.

[0063] The crystalline epoxy resin (D1) is preferably composed of one or more components selected from the group consisting of, for example, 1,3,5-tris(2,3-epoxypropyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, a hydroquinone-type crystalline epoxy resin (specific example: product name YDC-1312 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), a biphenyl-type crystalline epoxy resin (specific example: product name YX-4000 manufactured by Mitsubishi Chemical Corporation), a diphenyl ether-type crystalline epoxy resin (specific example: product number YSLV-80DE manufactured by Nippon Steel Chemical & Material Co., Ltd.), a bisphenol-type crystalline epoxy resin (specific example: product name YSLV-80XY manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), a tetrakisphenol ethane-type crystalline epoxy resin (specific example: product number GTR-1800 manufactured by Nippon Kayaku Co., Ltd.), and a bisphenol fluorene-type crystalline epoxy resin (specific example: an epoxy resin having structure (S7)).

[0064] The crystalline epoxy resin (D1) preferably has two epoxy groups in one molecule. In this case, it is possible to further prevent cracks from occurring in the cured product during repeated temperature changes.

[0065] The crystalline epoxy resin (D1) preferably has an epoxy equivalent of 150 g / eq or more and 300 g / eq or less. This epoxy equivalent is the gram weight of the crystalline epoxy resin (D1) containing 1 gram equivalent of epoxy groups. The crystalline epoxy resin (D1) has a melting point. Examples of the melting point of the crystalline epoxy resin (D1) include 70°C or more and 180°C or less.

[0066] In particular, the epoxy compound (D) preferably contains a crystalline epoxy resin (D1-1) having a melting point of 110°C or less. In this case, the developability of the photosensitive agent composition with an alkaline aqueous solution is particularly improved. Also, in this case, the resolution (openability) of the cured product layer formed from the photosensitive composition can also be improved. The crystalline epoxy resin (D1-1) having a melting point of 110°C or less can contain at least one component selected from the group consisting of, for example, biphenyl type epoxy resins (specific example: product number YX-4000 manufactured by Mitsubishi Chemical Corporation), biphenyl ether type epoxy resins (specific example: product number YSLV-80DE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), bisphenol type epoxy resins (specific example: product number YSLV-80XY manufactured by Nippon Steel & Sumikin Chemical), and bisphenol fluorene type crystalline epoxy resins (specific example: epoxy resin having structure (S7)).

[0067] The amorphous epoxy resin (D2) includes, for example, phenol novolac epoxy resin (product number EPICLON N-775 manufactured by DIC Corporation as a specific example), cresol novolac epoxy resin (product number EPICLON N-695 manufactured by DIC Corporation as a specific example), bisphenol A novolac epoxy resin (product number EPICLON N-865 manufactured by DIC Corporation as a specific example), bisphenol A type epoxy resin (product number jER1001 manufactured by Mitsubishi Chemical Corporation as a specific example), bisphenol F type epoxy resin (product number jER4004P manufactured by Mitsubishi Chemical Corporation as a specific example), bisphenol S type epoxy resin (product number EPICLON EXA-1514 manufactured by DIC Corporation as a specific example), bisphenol AD type epoxy resin, biphenyl novolac epoxy resin (product number NC-3000 manufactured by Nippon Kayaku Co., Ltd. as a specific example), hydrogenated bisphenol A type epoxy resin (product number ST-4000D manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. as a specific example), naphthalene type epoxy resin (product numbers EPICLON HP-4032, EPICLON HP-4700, EPICLON HP-4770 manufactured by DIC Corporation as specific examples), tertiary butyl catechol type epoxy resin (product number EPICLON HP-820 manufactured by DIC Corporation as a specific example), dicyclopentadiene type epoxy resin (product number EPICLON HP-7200 manufactured by DIC as a specific example), adamantane type epoxy resin (product number ADAMANTATEX-E-201 manufactured by Idemitsu Kosan Co., Ltd. as a specific example), special bifunctional epoxy resin (product numbers YL7175-500 and YL7175-1000 manufactured by Mitsubishi Chemical Corporation as specific examples; product numbers EPICLON TSR-960, EPICLON TER-601, EPILON TSR-250-80BX, EPICLON 1650-75MPX, EPICLON EXA-4850, EPICLON EXA-4816, EPICLON EXA-4822, and EPICLON EXA-9726 manufactured by DIC Corporation as specific examples;It is preferable to contain at least one component selected from the group consisting of a product number YSLV-120TE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., a rubber-like core-shell polymer-modified bisphenol A type epoxy resin (specific example: product number MX-156 manufactured by Kaneka Corporation), a rubber-like core-shell polymer-modified bisphenol F type epoxy resin (specific example: product number MX-136 manufactured by Kaneka Corporation), and a rubber particle-containing bisphenol F type epoxy resin (specific example: product number Kaneka Ace MX-130 manufactured by Kaneka Corporation).;

[0068] When the photosensitive composition contains an epoxy compound (D), the photosensitive composition preferably contains both a crystalline epoxy resin (D1) and an amorphous epoxy resin (D2). In this case, the plating resistance and insulation properties of the cured product produced from the photosensitive composition can be further improved.

[0069] The epoxy compound (D) may contain a phosphorus-containing epoxy resin. In this case, the flame retardancy of the cured product of the photosensitive composition is improved. The phosphorus-containing epoxy resin may be contained in the crystalline epoxy resin (D1) or may be contained in the amorphous epoxy resin (D2). Examples of the phosphorus-containing epoxy resin include a phosphoric acid-modified bisphenol F type epoxy resin (specific examples: product numbers EPICLON EXA-9726 and EPICLON EXA-9710 manufactured by DIC Corporation), product number Epotote FX-305 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., and the like.

[0070] The epoxy compound (D) may contain an epoxy compound (D3) having a bisphenol fluorene skeleton. This epoxy compound (D3) includes, for example, an epoxy compound (a1) having a bisphenol fluorene skeleton (S1) represented by the formula (1) described above.

[0071] The photosensitive composition preferably contains a solvent (E). The solvent (E) includes linear, branched, secondary or polyhydric alcohols such as water, ethanol, isobutanol, 1-butanol, isopropanol, hexanol, ethylene glycol, 3-methyl-3-methoxybutanol; ketones such as methyl ethyl ketone, cyclohexanone; aromatic hydrocarbons such as toluene, xylene; petroleum-based aromatic mixed solvents such as the Swasol series (manufactured by Maruzen Petrochemical Co., Ltd.), the Solvesso series (manufactured by Exxon Chemical Co., Ltd.); cellosolves such as cellosolve, butyl cellosolve; carbitols such as carbitol, butyl carbitol; alkylene glycol alkyl ethers such as ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol methyl ether; polypropylene glycol alkyl ethers such as dipropylene glycol methyl ether; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, carbitol acetate; and at least one compound selected from the group consisting of dialkyl glycol ethers. The solvent (E) preferably contains at least one alcohol-based solvent (E1) selected from the group consisting of propylene glycol monomethyl ether, ethanol, isobutanol, 1-butanol, isopropanol, hexanol, ethylene glycol, 3-methyl-3-methoxybutanol, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol methyl ether, and polypropylene glycol alkyl ethers such as dipropylene glycol methyl ether. That is, the photosensitive composition preferably contains the alcohol-based solvent (E1). In this case, when preparing the photosensitive composition, the coatability and uniformity of the photosensitive composition can be further improved. Also, even when a thermoplastic film is used as the substrate, it is difficult to cause dissolution of the substrate and it is difficult to damage the substrate. The solvent (E) more preferably contains propylene glycol monomethyl ether. In this case, the coatability and uniformity of the photosensitive composition can be further improved, and good drying properties can also be obtained.Propylene glycol monomethyl ether is more preferably contained in a proportion of 50% by mass or more with respect to the solvent (E).

[0072] The amounts of the components in the photosensitive composition are appropriately adjusted so that the photosensitive composition has photocurability and is developable with an alkaline solution.

[0073] The amount of the photosensitive resin (A) with respect to the solid content of the photosensitive composition is preferably 50% by mass or more and 90% by mass or less, more preferably 55% by mass or more and 85% by mass or less, and still more preferably 60% by mass or more and 80% by mass or less. Also, the amount of the photosensitive resin (A1) with respect to the solid content of the photosensitive composition is preferably 50% by mass or more and 90% by mass or less, more preferably 55% by mass or more and 85% by mass or less, and still more preferably 60% by mass or more and 80% by mass or less.

[0074] The amount of the photopolymerization initiator (B) with respect to the photosensitive resin (A) is preferably 0.5% by mass or more and 20% by mass or less, more preferably 1% by mass or more and 15% by mass or less, and still more preferably 2% by mass or more and 10% by mass or less.

[0075] The amount of the photopolymerizable compound (C) with respect to the photosensitive resin (A) is preferably 5% by mass or more and 60% by mass or less, more preferably 10% by mass or more and 50% by mass or less, and still more preferably in the range of 25% by mass or more and 45% by mass or less.

[0076] When the photosensitive composition contains an epoxy compound (D), regarding the amount of the epoxy compound (D), it is preferable that the total equivalent of the epoxy groups contained in the epoxy compound (D) is more than 0 equivalent and 2 equivalents or less with respect to 1 equivalent of the carboxyl groups contained in the photosensitive resin (A), more preferably more than 0 equivalent and 1 equivalent or less, and still more preferably more than 0 equivalent and 0.5 equivalent or less.

[0077] When the photosensitive composition contains the solvent (E), the amount of the solvent (E) is preferably 50% by mass or more and 95% by mass or less with respect to the whole photosensitive composition. In this case, when applying the photosensitive composition, the coatability of the photosensitive composition can be improved.

[0078] As long as the effects of the present embodiment are not inhibited, the photosensitive composition may further contain components other than the above components.

[0079] The photosensitive composition may contain at least one resin selected from the group consisting of blocked isocyanates such as tolylene diisocyanate-based, morpholine diisocyanate-based, isophorone diisocyanate-based, and hexamethylene diisocyanate-based blocked with caprolactam, oxime, malonic acid ester, etc.; butylated urea resin; various thermosetting resins other than the above; ultraviolet curable epoxy (meth)acrylate; resins obtained by adding (meth)acrylic acid to epoxy resins such as bisphenol A type, phenol novolac type, cresol novolac type, and alicyclic type; and high molecular compounds such as diallyl phthalate resin, phenoxy resin, urethane resin, and fluororesin.

[0080] The photosensitive composition may contain a curing agent for curing the epoxy compound (D). Examples of the curing agent include imidazole derivatives such as imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; amine compounds such as dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine; hydrazine compounds such as adipic acid hydrazide, sebacic acid hydrazide; phosphorus compounds such as triphenylphosphine; acid anhydrides; phenols; mercaptans; Lewis acid amine complexes; and onium salts, and can contain at least one component selected from the group consisting of these components. Commercially available products of these components are, for example, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (all are trade names of imidazole-based compounds) manufactured by Shikoku Kasei Co., Ltd., U-CAT3503N, UCAT3502T (both are trade names of dimethylamine-blocked isocyanate compounds) manufactured by San-Apro Ltd., DBU, DBN, U-CATSA102, U-CAT5002 (all are bicyclic amidine compounds and their salts).

[0081] The photosensitive composition may contain an adhesion promoter. Examples of the adhesion promoter include guanamine derivatives such as acetoguanamine (2,4-diamino-6-methyl-1,3,5-triazine) and benzoguanamine (2,4-diamino-6-phenyl-1,3,5-triazine), and S-triazine derivatives such as 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-4,6-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine·isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine·isocyanuric acid adduct, and silane coupling agents.

[0082] The photosensitive composition may contain a rheology control agent. The rheology control agent makes it easier to optimize the viscosity of the photosensitive composition. Examples of the rheology control agent include urea-modified medium-polar polyamides (product numbers BYK-430 and BYK-431 manufactured by Big Chemie Japan Co., Ltd.), polyhydroxycarboxylic acid amides (product number BYK-405 manufactured by Big Chemie Japan Co., Ltd.), modified ureas (product numbers BYK-410, BYK-411, and BYK-420 manufactured by Big Chemie Japan Co., Ltd.), high molecular weight urea derivatives (product number BYK-415 manufactured by Big Chemie Japan Co., Ltd.), urea-modified urethanes (product number BYK-425 manufactured by Big Chemie Japan Co., Ltd.), polyurethanes (product number BYK-428 manufactured by Big Chemie Japan Co., Ltd.), castor oil wax, polyethylene wax, polyamide wax, bentonite, kaolin, and clay.

[0083] The photosensitive composition may contain at least one component selected from the group consisting of a curing accelerator; a colorant; a copolymer such as silicone and acrylate; a leveling agent; a thixotropy agent; a polymerization inhibitor; an antihalation agent; a flame retardant; an antifoaming agent; an antioxidant; a surfactant; and a polymer dispersant.

[0084] In preparing the photosensitive composition of the present embodiment, it may be adjusted by an appropriate method. For example, the photosensitive composition can be adjusted by mixing and stirring the raw materials of the photosensitive composition. Further, for example, the photosensitive composition may be prepared by kneading by an appropriate kneading method using a three-roll mill, a ball mill, a sand mill, or the like. When the raw materials contain liquid components, low-viscosity components, etc., a part of the raw materials excluding the liquid components, low-viscosity components, etc. is first kneaded to prepare a mixture, and then the liquid components, low-viscosity components, etc. are added to and mixed with the obtained mixture to prepare the photosensitive composition. When the photosensitive composition contains a solvent (E), first, a part or all of the solvent among the raw materials may be mixed and then mixed with the rest of the raw materials.

[0085] The photosensitive composition of this embodiment has a light transmittance of 85% or more at wavelengths of 450 to 800 nm when a dry film having a thickness dimension of 10 μm is produced from this photosensitive composition. Thereby, a cured film with high transparency can be obtained and can be particularly preferably used for optical applications. The absorption spectrum of the dry film produced from the photosensitive composition is measured by a spectroscopic analyzer such as a spectrophotometer, for example. The specific measurement method can be carried out in the same manner as the evaluation tests (4-1) and (4-2) of the examples described later. By measuring the absorption spectrum of the dry film produced from the photosensitive composition, the light transmittance and the absorbance can be obtained. The light transmittance at wavelengths of 450 to 800 nm is more preferably 90% or more when a dry film having a thickness dimension of 10 μm is produced from the photosensitive composition. Also, the maximum value of the absorbance in the wavelength range of 250 to 800 nm is in the wavelength range of 300 to 330 nm, and the maximum value of the absorbance in the wavelength range of 300 to 330 nm is 1 or more. Thereby, the resolution of the cured product produced from the photosensitive composition can be further improved. The maximum value of the absorbance is more preferably 1.2 or more, and even more preferably 1.5 or more. Note that the above-mentioned "dry film having a thickness dimension of 10 μm" does not mean that the thickness of the dry film produced from the photosensitive composition of this embodiment is limited to 10 μm.

[0086] The photosensitive composition according to this embodiment is suitable as a material for electrically insulating layers such as solder resist layers, interlayer insulating layers, and plating resist layers. In particular, as described above, the photosensitive composition can have high transparency and high developability, so it is suitable as an electrically insulating material for optical applications.

[0087] The photosensitive composition according to this embodiment preferably has a property such that it can be developed with an aqueous sodium carbonate solution even when it is a film with a thickness of 25 μm. In this case, since it is possible to produce a sufficiently thick electrically insulating layer from the photosensitive composition by photolithography, the photosensitive composition can be widely applied to produce interlayer insulating layers, solder resist layers, etc. in printed wiring boards. Of course, it is also possible to produce an electrically insulating layer thinner than 25 μm from the photosensitive composition.

[0088] Whether a 25-μm-thick film can be developed with an aqueous sodium carbonate solution can be confirmed by the following method. A wet coating film is prepared by applying a photosensitive composition onto a suitable substrate, and a 25-μm-thick film is formed by heating this wet coating film at 80°C for 40 minutes. With a negative mask having an exposed portion that transmits ultraviolet light and a non-exposed portion that shields ultraviolet light directly applied to this film, the film is irradiated with ultraviolet light at a condition of 500 mJ / cm 2 for exposure. After exposure, a 1% Na 2 CO 3 aqueous solution at 30°C is injected onto the film at an injection pressure of 0.2 MPa for 90 seconds, and then pure water is injected at an injection pressure of 0.2 MPa for 90 seconds. As a result of observing the film after this treatment, when the portion corresponding to the non-exposed portion in the film is removed and no residue is observed, it can be determined that a 25-μm-thick film is developable with an aqueous sodium carbonate solution. Note that for films of other thicknesses (for example, 30 μm), it is similarly possible to confirm whether development with an aqueous sodium carbonate solution is possible.

[0089] Next, the laminate 10 according to the present embodiment will be described with reference to FIGS. 1A and 1B.

[0090] The laminate 10 includes a substrate 1 and a transparent cured film 40 that overlaps the substrate 1. The transparent cured film 40 contains a cured product of the photosensitive composition described above. Since the laminate 10 includes the transparent cured film 40, it can be suitably used for optical applications.

[0091] Examples of the substrate 1 include appropriate substrates such as glass, plastic, and ceramic. More specifically, for example, the substrate 1 includes films made of thermoplastic resins such as polyethylene terephthalate, cycloolefin polymer, liquid crystal polymer, and polycarbonate. Further, the substrate 1 may be a substrate including an insulating layer 2 and conductor wiring 3 on the insulating layer 2 (see FIG. 2A).

[0092] As described above, the transparent hard film 40 contains a cured product of the photosensitive composition. Therefore, the transparent hard film 40 can also be used as a plating resist. Thus, the laminate 10 may be provided with a plating layer such as a through-hole plating 8. Specifically, for example, the laminate 10 can be produced by forming a coating film by applying a photosensitive composition onto the substrate 1, and then performing a plating process in the gaps of the cured product (transparent hard film 40) produced by exposing and developing the coating film of the photosensitive composition by photolithography or the like (see FIG. 1B).

[0093] The laminate 10 is not limited to the configurations shown in FIGS. 1A and 1B, and may include, for example, a layer different from the substrate 1 and the transparent hard film 40 between the substrate 1 and the transparent hard film 40.

[0094] The laminate 10 according to the present embodiment can be produced, for example, as follows.

[0095] On the substrate 1, a dry film with a thickness of 10 μm or less is formed by applying a photosensitive composition. After partially exposing the dry film, development is performed with an alkaline developer to form a pattern, thereby producing the transparent hard film 40 overlapping the substrate 1. Thereby, the laminate 10 including the substrate 1 and the transparent hard film 40 overlapping on the substrate 1 is obtained.

[0096] A method for manufacturing the laminate 10 will be described more specifically with reference to FIGS. 2A to 2E by way of an example.

[0097] First, as shown in FIG. 2A, the substrate 1 is prepared. In FIG. 2A, the substrate 1 includes at least one insulating layer 2 and at least one conductor wiring 3, but is not limited thereto. The substrate 1 may be, for example, a film material made of a thermoplastic resin. Hereinafter, as an example, the case where the substrate 1 includes the insulating layer 2 and the conductor wiring 3 will be described. Also, the conductor wiring 3 provided on the substrate 1 will be hereinafter referred to as the first conductor wiring 31.

[0098] Subsequently, as shown in FIG. 2B, a film 4 is formed from a photosensitive composition on one surface of the substrate 1. Examples of the method for forming the film 4 include a coating method and a dry film method.

[0099] In the coating method, for example, a photosensitive composition is applied onto the substrate 1 to form a wet coating film. The method for applying the photosensitive composition is selected from the group consisting of known methods such as a dipping method, a spraying method, a spin coating method, a roll coating method, a curtain coating method, and a screen printing method. Subsequently, in order to volatilize the organic solvent in the photosensitive composition, the wet coating film is dried, for example, at a temperature within the range of 60 to 130°C, whereby the film 4 can be obtained.

[0100] In the dry film method, first, a photosensitive composition is applied onto a suitable support made of polyester or the like and then dried to form a dry film, which is a dried product of the photosensitive composition, on the support. Thereby, a dry film with a support, which includes the dry film and the support supporting the dry film, is obtained. After overlapping the dry film in this dry film with a support on the substrate 1, pressure is applied to the dry film and the substrate 1, and subsequently, the support is peeled off from the dry film, thereby transferring the dry film from the support onto the substrate 1. Thereby, a film 4 made of the dry film is provided on the substrate 1.

[0101] By exposing the film 4, the film 4 is partially cured as shown in FIG. 2C. For this purpose, for example, after applying a negative mask to the film 4, the film 4 is irradiated with ultraviolet rays. The negative mask includes an exposure portion that transmits ultraviolet rays and a non-exposure portion that shields ultraviolet rays, and the non-exposure portion is provided at a position that coincides with the position of the through hole 9. The negative mask is a phototool such as a mask film or a dry plate. The light source of ultraviolet rays is selected from the group consisting of, for example, a chemical lamp, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a metal halide lamp, an LED, a YAG, a g-line (436 nm), an h-line (405 nm), an i-line (365 nm), and a combination of two or more of the g-line, h-line, and i-line. The light source of ultraviolet rays is not limited to these, and any light source that can irradiate ultraviolet rays capable of curing the photosensitive composition may be used.

[0102] Note that the exposure method may be a method other than the method using a negative mask. For example, the film 4 may be exposed by a direct drawing method in which ultraviolet rays emitted from a light source are irradiated only on the portion of the film 4 to be exposed. The light source applied to the direct drawing method is selected from the group consisting of, for example, a chemical lamp, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a metal halide lamp, an LED, a YAG, a g-line (436 nm), an h-line (405 nm), an i-line (365 nm), and a combination of two or more of the g-line, h-line, and i-line. The light source of ultraviolet rays is not limited to these, and any light source that can irradiate ultraviolet rays capable of curing the photosensitive composition may be used.

[0103] Also, in the dry film method, after overlapping the dry film in the dry film with a support on the substrate 1, without peeling the support, the film 4 made of the dry film is exposed by irradiating ultraviolet rays through the support, and then the support may be peeled from the film 4 before the development process.

[0104] Subsequently, by subjecting the film 4 to a development process, the unexposed portion 5 of the film 4 shown in FIG. 2C is removed, and thereby, a hole 6 is provided at a position where a through-hole 9 is formed as shown in FIG. 2D. In the development process, an appropriate developer can be used according to the composition of the photosensitive composition. The developer is, for example, an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide, or an organic amine. More specifically, the alkaline aqueous solution contains at least one component selected from the group consisting of sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, ammonium hydrogen carbonate, sodium hydroxide, potassium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, and lithium hydroxide. The solvent in the alkaline aqueous solution may be only water or a mixture of water and a hydrophilic organic solvent such as lower alcohols. The organic amine contains at least one component selected from the group consisting of, for example, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, and triisopropanolamine.

[0105] The developer is preferably an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide, and particularly preferably an aqueous sodium carbonate solution. In this case, improvement of the working environment and reduction of the burden of waste treatment can be achieved.

[0106] Thereby, a laminate 10 including a transparent cured film 40 containing a cured product of the photosensitive composition is obtained on the substrate 1.

[0107] The following treatments may be further performed on the transparent cured film 40 produced above.

[0108] For example, the transparent hard film 40 may be thermally cured by heating. The heating conditions are, for example, within the range of a heating temperature of 80 to 200°C and a heating time of 2 to 120 minutes. In this case, for example, the performance such as the strength, hardness, and chemical resistance of the interlayer insulating layer formed from the transparent hard film 40 is improved. If necessary, ultraviolet rays may be further irradiated onto the transparent hard film 40 either before or after heating, or both. Also, ultraviolet rays may be further irradiated onto the transparent hard film 40 without heating. In this case, the photocuring of the transparent hard film 40 can be further advanced.

[0109] Furthermore, the transparent hard film 40 may be subjected to a plating process. An appropriate method can be adopted for the plating process. For example, on the transparent hard film 40 in the laminate 10, the second conductor wiring 32 and the hole plating 8 can be provided by a method such as the additive method. In this case, as shown in FIG. 2E, a printed wiring board 11 is obtained that includes the first conductor wiring 31, the second conductor wiring 32, the transparent hard film 40 interposed between the first conductor wiring 31 and the second conductor wiring 32, and the through hole 9 that electrically connects the first conductor wiring 31 and the second conductor wiring 32.

[0110] Note that in FIG. 2E, the hole plating 8 has a cylindrical shape that covers the inner surface of the hole 6, but the inside of the entire hole 6 may be filled with the hole plating 8. When providing the hole plating 8, an electroless metal plating process can be performed on a part of the roughened outer surface and the inner surface of the hole 6 described later to form an initial wiring. Thereafter, the hole plating 8 can be formed by depositing the metal in the electrolyte plating solution on the initial wiring by an electrolytic metal plating process.

[0111] Also, before performing the plating treatment, the surface of the transparent cured film 40 may be roughened by subjecting the transparent cured film 40 to a roughening treatment. For example, when roughening a part of the outer surface of the transparent cured film 40 and the entire inner surface of the hole 6, it can be performed in the same procedure as a general desmear treatment using an oxidizing agent. For example, an oxidizing agent is brought into contact with the outer surface of the transparent cured film 40 to impart a rough surface to the transparent cured film 40. However, it is not limited thereto, and methods that do not impart a rough surface to the cured product, such as plasma treatment, corona treatment, UV treatment, ozone treatment, and primer treatment, can also be appropriately employed. The oxidizing agent may be an oxidizing agent available as a desmear solution. For example, an oxidizing agent can be constituted by a commercially available swelling solution for desmear and a desmear solution. Such an oxidizing agent can contain, for example, at least one permanganate selected from the group consisting of sodium permanganate and potassium permanganate.

[0112] The thickness of the transparent cured film 40 is not particularly limited, but is preferably 0.1 μm or more and 100 μm or less. The thickness of the transparent cured film 40 is more preferably 0.2 μm or more and 50 μm or less, still more preferably 0.3 μm or more and 20 μm or less, and particularly preferably 1 μm or more and 15 μm or less. As described above, the transparent cured film 40 can be suitably used as, for example, an interlayer insulating layer. When the transparent cured film 40 is used as an interlayer insulating layer, in order to ensure high resolution of the interlayer insulating layer, it is preferably 1 μm or more and 25 μm or less, and more preferably within the range of 1 μm or more and 10 μm or less.

[0113] As described above, a transparent cured film 40 made of a cured product of the photosensitive composition is provided on the substrate 1.

[0114] In the photosensitive composition of the present embodiment, an electrically insulating layer such as a plating resist layer, a solder resist layer, and an interlayer insulating layer can be formed particularly well from this dry film, which is the dried product, or from a coating film of the photosensitive composition.

Examples

[0115] Hereinafter, specific embodiments of the present invention will be presented. However, the present invention is not limited only to the embodiments.

[0116] (1) Synthesis of photosensitive resin (1-1) Synthesis Example 1 (Photosensitive resin A-1) Into a four-necked flask equipped with a reflux condenser, thermometer, air blowing tube, and stirrer, 252 parts by mass of a bisphenol fluorene type epoxy compound (an epoxy compound represented by formula (2) and having an epoxy equivalent of 252 g / eq in which all of R 1 ~R 8 are hydrogen), 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 parts by mass of methylhydroquinone, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in the flask under air bubbling with stirring under the conditions of a heating temperature of 115°C and a heating time of 12 hours. Thereby, a solution of the intermediate was prepared.

[0117] Subsequently, 58.8 parts by mass of 3,3’,4,4’-biphenyltetracarboxylic dianhydride and 7 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling with stirring under the conditions of a heating temperature of 115°C and a heating time of 6 hours. Thereby, a 65% by mass solution of photosensitive resin A1 was obtained. The polydispersity (Mw / Mn) of photosensitive resin A1 was 2.11, the number average molecular weight (Mn) was 1486, and the acid value was 59 mgKOH.

[0118] (1-2) Synthesis Example 2 (Photosensitive resin A-2) Into a four-necked flask equipped with a reflux condenser, thermometer, air blowing tube, and stirrer, a bisphenol fluorene type epoxy compound (represented by formula (2), and R 1 ~R 8252 parts by mass of an epoxy compound having an epoxy equivalent of 252 g / eq in which all are hydrogen, 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 part by mass of 4-methoxyphenol, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in a flask under air bubbling with stirring at a heating temperature of 115 °C for 12 hours. Thereby, a solution of the intermediate was prepared.

[0119] Subsequently, 73.55 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride and 15 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling with stirring at a heating temperature of 115 °C for 6 hours. Thereby, a 65% by mass solution of photosensitive resin A2 was obtained. The polydispersity (Mw / Mn) of photosensitive resin A2 was 2.04, the number average molecular weight (Mn) was 1682, and the acid value was 69 mgKOH.

[0120] (1 - 3) Synthesis Example 3 (Photosensitive Resin A-3) Into a four-necked flask equipped with a reflux condenser, thermometer, air blowing tube, and stirrer, 252 parts by mass of a bisphenol fluorene type epoxy compound (represented by formula (2), and in formula (2), R 1 ~R 8 is an epoxy compound having an epoxy equivalent of 252 g / eq in which all are hydrogen), 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 part by mass of 4-methoxyphenol, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in a flask under air bubbling with stirring at a heating temperature of 115 °C for 12 hours. Thereby, a solution of the intermediate was prepared.

[0121] Subsequently, 15.4 parts by mass of 1,2,3,6-tetrahydrophthalic anhydride, 58.8 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 15 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling with stirring at a heating temperature of 115°C for 6 hours, and then further heated under air bubbling with stirring at a heating temperature of 60°C for 6 hours. As a result, a 65% by mass solution of photosensitive resin A3 was obtained. The polydispersity (Mw / Mn) of photosensitive resin A3 was 1.99, the number average molecular weight (Mn) was 1460, and the acid value was 71 mgKOH.

[0122] (1-4) Synthesis Example 4 (Photosensitive Resin A-4) Into a four-necked flask equipped with a reflux condenser, thermometer, air inlet tube, and stirrer, 252 parts by mass of a bisphenol fluorene type epoxy compound (an epoxy compound represented by formula (2) with an epoxy equivalent of 252 g / eq where all R 1 ~R 8 in formula (2) are hydrogen), 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 parts by mass of 4-methoxyphenol, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in the flask under air bubbling with stirring at a heating temperature of 115°C for 12 hours. As a result, a solution of the intermediate was prepared.

[0123] Subsequently, 60.8 parts by mass of 1,2,3,6-tetrahydrophthalic anhydride, 58.8 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 40 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling with stirring at a heating temperature of 115°C for 6 hours, and then further heated under air bubbling with stirring at a heating temperature of 60°C for 6 hours. As a result, a 65% by mass solution of photosensitive resin A4 was obtained. The polydispersity (Mw / Mn) of photosensitive resin A4 was 1.89, the number average molecular weight (Mn) was 1552, and the acid value was 104 mgKOH.

[0124] (1 - 5) Synthesis Example 5 (Photosensitive Resin A-5) Into a four-necked flask equipped with a reflux condenser, thermometer, air inlet tube, and stirrer, 252 parts by mass of a bisphenol fluorene type epoxy compound (epoxy compound with an epoxy equivalent of 252 g / eq in which all R 1 ~R 8 in formula (2) are hydrogen), 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 parts by mass of 4-methoxyphenol, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in the flask under air bubbling with stirring at a heating temperature of 115°C for 12 hours. As a result, a solution of the intermediate was prepared.

[0125] Subsequently, 115.5 parts by mass of 1,2,3,6-tetrahydrophthalic anhydride, 7.355 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 42 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling with stirring at a heating temperature of 115°C for 6 hours, and then further heated under air bubbling with stirring at a heating temperature of 60°C for 6 hours. As a result, a 65% by mass solution of photosensitive resin A5 was obtained. The polydispersity (Mw / Mn) of photosensitive resin A5 was 1.28, the number average molecular weight (Mn) was 1,054, and the acid value was 102 mgKOH.

[0126] (1-6) Synthesis Example 6 (Photosensitive Resin A-6) Into a four-necked flask equipped with a reflux condenser, thermometer, air inlet tube, and stirrer, 252 parts by mass of a bisphenol fluorene type epoxy compound (an epoxy compound represented by formula (2) with an epoxy equivalent of 252 g / eq where all R 1 ~R 8 in formula (2) are hydrogen), 64.8 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 parts by mass of 4-methoxyphenol, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in the flask under air bubbling with stirring at a heating temperature of 115°C for 12 hours. As a result, a solution of the intermediate was prepared.

[0127] Subsequently, 60.8 parts by mass of 1,2,3,6-tetrahydrophthalic anhydride, 58.8 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 36 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling with stirring at a heating temperature of 115°C for 6 hours, and then further heated under air bubbling with stirring at a heating temperature of 60°C for 6 hours. As a result, a 65% by mass solution of photosensitive resin A6 was obtained. The polydispersity (Mw / Mn) of photosensitive resin A6 was 2.21, the number average molecular weight (Mn) was 1753, and the acid value was 98 mgKOH.

[0128] (1-7) Synthesis Example 7 (Photosensitive Resin B-1) Into a four-necked flask equipped with a reflux condenser, thermometer, air inlet tube, and stirrer, 252 parts by mass of a bisphenol fluorene type epoxy compound (epoxy compound having an epoxy equivalent of 252 g / eq represented by formula (2) and in which all of R 1 ~R 8 are hydrogen), 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 parts by mass of 4-methoxyphenol, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in the flask under air bubbling with stirring at a heating temperature of 115°C for 12 hours. As a result, a solution of the intermediate was prepared.

[0129] Subsequently, 44.13 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added to the solution of the intermediate in the flask. These were heated under air bubbling with stirring at a heating temperature of 115°C for 6 hours, and then further heated under air bubbling with stirring at a heating temperature of 60°C for 6 hours. As a result, a 65% by mass solution of photosensitive resin B1 was obtained. The polydispersity (Mw / Mn) of photosensitive resin B1 was 1.56, the number average molecular weight (Mn) was 1364, and the acid value was 46 mgKOH.

[0130] (1-8) Synthesis Example 8 (Photosensitive Resin B-2) Into a four-necked flask equipped with a reflux condenser, thermometer, air blowing tube, and stirrer, 650 parts by mass of a bisphenol fluorene type epoxy compound (epoxy compound having an epoxy equivalent of 650 g / eq represented by formula (2) and in which R 1 ~R 8 are all hydrogen), 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 parts by mass of 4-methoxyphenol, and 500 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in the flask under air bubbling with a heating temperature of 115 °C and a heating time of 12 hours. Thereby, a solution of the intermediate was prepared.

[0131] Subsequently, 60.8 parts by mass of 1,2,3,6-tetrahydrophthalic anhydride, 58.8 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 4 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling with a heating temperature of 115 °C and a heating time of 6 hours, and further heated under air bubbling with a heating temperature of 60 °C and a heating time of 6 hours. Thereby, a 65% by mass solution of photosensitive resin B2 was obtained. The polydispersity (Mw / Mn) of photosensitive resin B2 was 4.12, the number average molecular weight (Mn) was 1324, and the acid value was 55 mgKOH.

[0132] (1-9) Synthesis Example 9 (Photosensitive Resin C-1) Into a four-necked flask equipped with a reflux condenser, thermometer, air blowing tube, and stirrer, a bisphenol fluorene type epoxy compound (represented by the above formula (2) and in which R 1 ~R 8252 parts by mass of an epoxy compound having an epoxy equivalent of 252 g / eq, all of which is hydrogen, 72 parts by mass of acrylic acid, 1.5 parts by mass of triphenylphosphine, 0.2 parts by mass of 4-methoxyphenol, and 200 parts by mass of propylene glycol monomethyl ether acetate were added. A mixture was prepared by stirring these under air bubbling. This mixture was heated in a flask under air bubbling and stirring at a heating temperature of 115 °C for 12 hours. Thereby, a solution of the intermediate was prepared.

[0133] Subsequently, 123.2 parts by mass of 1,2,3,6-tetrahydrophthalic anhydride and 42 parts by mass of propylene glycol monomethyl ether acetate were added to the solution of the intermediate in the flask. These were heated under air bubbling and stirring at a heating temperature of 115 °C for 6 hours, and further heated under air bubbling and stirring at a heating temperature of 60 °C for 6 hours. Thereby, a 65% by mass solution of photosensitive resin C1 was obtained. The polydispersity (Mw / Mn) of photosensitive resin C1 was 1.18, the number average molecular weight (Mn) was 783, and the acid value was 102 mgKOH.

[0134] (1 - 10) Synthesis Example 10 (Photosensitive Resin C-2) Into a four-necked flask equipped with a reflux condenser, thermometer, air inlet tube, and stirrer, 80 parts by mass of methacrylic acid, 95 parts by mass of methyl methacrylate, 25 parts by mass of styrene, 80 parts by mass of dipropylene glycol monomethyl ether acid, 430 parts by mass of dipropylene glycol monomethyl ether, and 3.5 parts by mass of azobisisobutyronitrile were added. The mixture in this four-necked flask was heated at a heating temperature of 75 °C for 5 hours under stirring in a nitrogen stream to advance the polymerization reaction. Thereby, a copolymer solution with a concentration of 32% was obtained.

[0135] Subsequently, 0.1 part by mass of hydroquinone, 64 parts by mass of glycidyl methacrylate, and 0.8 part by mass of dimethylbenzylamine were added to this copolymer solution. While stirring these, an addition reaction was allowed to proceed by heating under the conditions of a heating temperature of 80°C and a heating time of 24 hours. Thereby, a 38% by mass solution of photosensitive resin C2 was obtained. The polydispersity (Mw / Mn) of photosensitive resin C2 was 2.13, the number average molecular weight (Mn) was 10,530, and the acid value was 104 mgKOH.

[0136] (2) Preparation of photosensitive composition [Each example and comparative example] The components shown in the table below were added into a flask and stirred and mixed at a temperature of 35°C to obtain a photosensitive composition. The details of the components shown in the table are as follows. · Photoinitiator A: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (manufactured by IGM Resins B.V., product number Omnirad TPO H). · Photoinitiator B: bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (manufactured by IGM Resins B.V., product number Omnirad 819). · Photoinitiator C: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (manufactured by IGM Resins B.V., product number Omnirad 907). · Photoinitiator D: 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone (manufactured by IGM Resins B.V., product number Omnirad 369). · Photoinitiator E: ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetoxyoxime) (manufactured by BASF Japan Ltd., product number Irgacure OXE02). · Photoinitiator F: 1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins B.V., product number Omnirad 184). · Photopolymerizable compound A: trimethylolpropane triacrylate. · Photo-polymerizable compound B: tricyclodecane dimethanol diacrylate. · Photo-polymerizable compound C: dipentaerythritol penta and hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., product number KAYARAD DPHA). · Antioxidant: Pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) (manufactured by BASF Japan Ltd., product number Irganox 1010). · Surface modifier: surfactant (manufactured by DIC Corporation, product number Megafac F-557) · Epoxy compound A: biphenyl type crystalline epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name YX-4000, melting point 105 °C, epoxy equivalent 187 g / eq.). · Epoxy compound B: bisphenol A type epoxy resin, manufactured by Nippon Steel Chemical & Material Co., Ltd., product number YD-128, epoxy equivalent 187 g / eq. · Solvent A: propylene glycol monomethyl ether. · Solvent B: methyl ethyl ketone. · Solvent C: propylene glycol monomethyl ether acetate.

[0137] (3) Preparation of test pieces Test pieces were prepared from the photosensitive composition prepared in (2) above as follows.

[0138] First, a glass epoxy copper-clad laminate (FR-4 type) having a copper foil with a thickness of 17.5 μm was prepared. The surface portion of about 1 μm thickness in the copper foil of this printed wiring board was roughened by dissolving and removing it with an etching agent (product number CZ-8101 manufactured by Meck Co., Ltd.). On this substrate, the compositions of each example and comparative example were applied with an applicator to form a wet coating film. This coating film was thermally dried under the conditions of 120 °C for 5 minutes to form a film with a thickness of 10 μm on the copper foil.

[0139] This film has a pattern including lines with line widths of 6 μm, 8 μm, and 10 μm and has a non-exposed portion. With a negative mask directly applied, the film was irradiated with ultraviolet rays by an ultra-high pressure mercury lamp under the condition of 400 mJ / cm 2 After exposure, the film was developed.

[0140] In the development process, a 1% Na 2 CO 3 aqueous solution at 30 °C was sprayed onto the film at an injection pressure of 0.05 MPa for 60 seconds. For those that could not be developed after spraying for 60 seconds, spraying was carried out for 90 seconds. For those that could not be developed after spraying for 90 seconds, spraying was carried out for 120 seconds. Subsequently, pure water was sprayed onto the film at an injection pressure of 0.05 MPa for 60 seconds. Thereby, the unexposed portions of the film were removed to form a pattern with missing lines on the film.

[0141] Subsequently, for Examples 14 and 15, heat curing was carried out under the conditions of 150 °C for 30 minutes.

[0142] Subsequently, for each of the examples and comparative examples, the film was irradiated with ultraviolet rays by a metal halide lamp under the condition of 1000 mJ / cm 2 to prepare a cured product of the photosensitive composition. Thereby , test pieces were obtained.

[0143] (4) Evaluation (4-1) Transmittance A wet coating film was formed by applying the photosensitive composition prepared in (2) above onto a film made of polyethylene terephthalate (PET: Polyethyleneterephthalate) with an applicator. This coating film was heated and dried at 120 °C for 5 minutes to prepare a film (dry film) with a thickness of 10 μm on the PET film. Subsequently, the entire surface of the film prepared on the PET film was irradiated with ultraviolet rays by an ultra-high pressure mercury lamp under the condition of 400 mJ / cm 2 After exposure, the film was developed. In the development process, a 1% Na 2 CO 3The aqueous solution was injected for 60 seconds at an injection pressure of 0.05 MPa. Subsequently, pure water was injected onto the film for 60 seconds at an injection pressure of 0.05 MPa.

[0144] Subsequently, the film was irradiated with ultraviolet light under the condition of 1000 mJ / cm 2 by a metal halide lamp to cure the photosensitive composition. The cured product prepared on a PET film was set in an ultraviolet-visible near-infrared spectrophotometer (model UV-3100PC manufactured by Shimadzu Corporation), and the transmittance of the cured product in the wavelength range of 450 to 800 nm was measured. As a reference, a PET film as the base material was used. The obtained transmittance curves were evaluated according to the following criteria, and the results are shown in Tables 1 to 3. ○: In the wavelength range of 450 nm to 800 nm, all transmittances were 90% or more. △: In the wavelength range of 450 nm to 800 nm, there was a wavelength range where the transmittance was 85% or more and less than 90%. ×: In the wavelength range of 450 nm to 800 nm, there was a wavelength range where the transmittance was less than 85%.

[0145] Also, for each of the measurement samples of the cured product prepared by the above method, after storage at -40°C for 1000 hours and after storage at 105°C for 1000 hours, the transmittance was measured by the same method as above to obtain a transmittance curve, and the transmittance curve was evaluated according to the same criteria as above.

[0146] (4-2) Absorption spectrum A wet coating film was prepared by applying the photosensitive composition prepared in (2) above onto a PET film using an applicator. This coating film was heated and dried under the conditions of 120 °C for 5 minutes to form a film (dry film) with a thickness of 10 μm on the PET film. The film formed on the PET film was set in an ultraviolet-visible-near-infrared spectrophotometer (model UV-3100PC manufactured by Shimadzu Corporation), and the absorption spectrum of the film in the range of 250 to 800 nm was measured. As a reference, a PET film as the base material was used. The obtained absorption spectra were evaluated according to the following criteria, and the results are shown in Tables 1 to 3. Also, in Tables 1 to 3, in the column of [maximum absorbance value at 300 nm to 330 nm], the maximum absorbance value is shown in parentheses.

[0147] [Wavelength range including the maximum absorbance value] ○: In the wavelength range of 250 nm to 800 nm, the maximum absorbance value is in the wavelength range of 300 nm to 330 nm. ×: In the wavelength range of 250 nm to 800 nm, the maximum absorbance value is not in the wavelength range of 300 nm to 330 nm.

[0148] [Maximum absorbance value at 300 nm to 330 nm] ○: In the wavelength range of 300 nm to 330 nm, the maximum absorbance value is 1 or more. ×: In the wavelength range of 300 nm to 330 nm, the maximum absorbance value is less than 1.

[0149] (4-3) Low tackiness Similar to (4-1) above, a film (dry film) was formed on a PET film, and stickiness was evaluated by pressing a finger against the dry film.

[0150] Furthermore, similar to (4-1) above, the film on the PET film was exposed and cured to produce a cured product of the photosensitive resin. When curing the photosensitive resin, the cured product of the photosensitive resin after peeling the negative mask after exposure was observed.

[0151] From the above results, low tackiness was evaluated according to the following criteria, and the results are shown in Tables 1 to 3. A: Even when pressing a finger on the film after heat drying, stickiness is not felt, and no sticking marks of the negative mask are seen on the cured product after exposure. B: When pressing a finger on the film after heat drying, stickiness is felt, but no sticking marks of the negative mask are seen on the cured product after exposure. C: When pressing a finger on the film after heat drying, stickiness is felt, and sticking marks of the negative mask are seen on the cured product after exposure. D: When pressing a finger on the film after heat drying, strong stickiness is felt, and furthermore, when peeling the negative mask after exposure, transfer of the cured product to the negative mask is seen.

[0152] (4-4) Developability In the preparation of the test piece in (3) above, the test piece after development processing was observed, evaluated according to the following criteria, and the results are shown in Tables 1 to 3. A: No development residue is seen in 1% Na 2 CO 3 aqueous solution, at 30 °C, 0.05 MPa, and developed for 60 seconds. B: Development residue is seen in 1% Na 2 CO 3 aqueous solution, at 30 °C, 0.05 MPa, and developed for 60 seconds, but no development residue is seen in 1% Na 2 CO 3 aqueous solution, at 30 °C, 0.05 MPa, and developed for 90 seconds. C: Development residue is seen in 1% Na 2 CO 3 aqueous solution, at 30 °C, 0.05 MPa, and developed for 90 seconds, but no development residue is seen in 1% Na 2 CO 3 aqueous solution, at 30 °C, 0.05 MPa, and developed for 120 seconds. D: Development residue is seen in 1% Na 2 CO 3 aqueous solution, at 30 °C, 0.05 MPa, and developed for 120 seconds.

[0153] (4-5) Resolution The test pieces prepared in (3) above were observed and evaluated according to the following criteria, and the results are shown in Tables 1 to 3. A: The space with a line width of 6 μm is resolvable. B: The space with a line width of 6 μm is not resolvable, but the space with a line width of 8 μm is resolvable. C: The space with a line width of 8 μm is not resolvable, but the space with a line width of 10 μm is resolvable. D: The space with a line width of 10 μm is not resolvable.

[0154] (4-6) Electroless plating resistance (plating resistance) On the exposed part outside the copper foil of the test piece prepared in (3) above, a nickel plating layer was prepared using a commercially available electroless nickel plating bath, and then a gold plating layer was formed using a commercially available electroless gold plating bath. The appearance of the layer made of the cured product and the metal layer was observed visually. In addition, a cellophane tape peeling test was performed on the layer made of the cured product of the photosensitive resin. Then, the results of the above tests were evaluated according to the following criteria, and the results are shown in Tables 1 to 3. A: No abnormality was observed in the appearance of the layer made of the cured product and the metal layer, and peeling of the layer made of the cured product did not occur in the cellophane tape peeling test. B: Slight discoloration was observed in the layer made of the cured product, but peeling of the layer made of the cured product did not occur in the cellophane tape peeling test. C: Discoloration was observed in the layer made of the cured product, but peeling of the layer made of the cured product did not occur in the cellophane tape peeling test. D: Lifting of the layer made of the cured product was observed, and peeling of the layer made of the cured product occurred in the cellophane tape peeling test.

[0155] (4-7) Electrical insulation Using the B pattern of a printed circuit board (thickness 1.6 mm) defined by IPC, the photosensitive composition was applied and cured by the method described above, and the electrical insulation of the obtained cured film was evaluated according to the following criteria. Measurement conditions: Measurement time 60 seconds, applied voltage 500 V. A: Insulation resistance value is 10 11Ω or more. B: The insulation resistance value is 10 10 Ω or more and 10 11 Ω or less. C: The insulation resistance value is 10 9 Ω or more and 10 10 Ω or less. D: The insulation resistance value is less than 10 9 Ω.

[0156] (4-8) Coating property on each substrate and resistance of the substrate By applying the photosensitive composition prepared in (2) above on a substrate (PET substrate, COP substrate, or PC substrate), followed by heat drying, exposure, and development, a cured product of the photosensitive resin was produced on the substrate, and the resistance of the substrate to the photosensitive resin was evaluated. The specific test method is as follows.

[0157] (4-8-1) PET substrate On a PET film, the photosensitive composition prepared in (2) was subjected to heat drying, exposure, and development in the same manner as described in the preparation of the test piece in (3) above to produce an evaluation sample. For Examples 14 and 15, "thermal curing under the conditions of 150 °C for 30 minutes" described in (3) above was not performed. The obtained evaluation samples were visually observed and evaluated according to the following criteria. ○: A uniform cured film is obtained. Also, no abnormalities such as whitening, cracking, and cracking occur on the substrate. ×: A uniform cured film cannot be obtained. Or, abnormalities such as whitening, cracking, and cracking occur on the substrate.

[0158] (4-8-2) COP substrate Except that the substrate in (4-8-1) above was changed to a film made of cycloolefin polymer (COP: Cyclo Olefin polymer), a cured product of the photosensitive resin was produced on the substrate in the same manner as in (4-8-1) above to obtain an evaluation sample. The obtained evaluation samples were visually observed and evaluated according to the following criteria. ○: A uniform cured film is obtained. Also, no abnormalities such as whitening, cracking, and cracking occur on the substrate. ×: A uniform cured film cannot be obtained, or abnormalities such as whitening, cracking, and splitting occur on the substrate.

[0159] (4-8-3) PC substrate Except for changing the substrate in the above (4-8-1) to a film made of polycarbonate (PC: Polycarbonate), a cured product of a photosensitive resin was produced on the substrate in the same manner as in the above (4-8-1) to obtain a sample for evaluation. The obtained sample for evaluation was visually observed and evaluated according to the following criteria. ○: A uniform cured film is obtained. Also, no abnormalities such as whitening, cracking, and splitting occur on the substrate. ×: A uniform cured film cannot be obtained, or abnormalities such as whitening, cracking, and splitting occur on the substrate.

[0160]

Table 1

[0161]

Table 2

[0162]

Table 3

Explanation of Symbols

[0163] 1 Substrate 40 Transparent cured film 10 Laminate

Claims

1. A photosensitive resin (A) containing a resin having an ethylenically unsaturated group and a carboxyl group; A photopolymerization initiator (B); A photosensitive composition comprising a photopolymerizable compound (C), The photosensitive resin (A) contains a photosensitive resin (A1) produced by reacting a product produced by reacting an epoxy compound (a1) having at least two epoxy groups with a carboxylic acid (a2) having an ethylenically unsaturated group, and an acid anhydride (a3) ​​containing an acid dianhydride (a4), the photosensitive resin (A1) has a number average molecular weight Mn of 500 or more and 2000 or less, a polydispersity Mw / Mn of 1.2 or more and 2.8 or less, and an acid value of 55 mgKOH / g or more and 130 mgKOH / g or less; The epoxy compound (a1) contains a compound having a bisphenol fluorene skeleton, the photosensitive composition does not contain an epoxy compound (D), or contains the epoxy compound (D) such that the total equivalent of the epoxy groups contained in the epoxy compound (D) is more than 0 equivalent and 0.6 equivalents or less relative to 1 equivalent of the carboxyl groups contained in the photosensitive resin (A); When a dry film having a thickness of 10 μm is produced from the photosensitive composition, the light transmittance at a wavelength of 450 to 800 nm is 85% or more, the maximum absorbance of the dry film in the wavelength range of 250 to 800 nm is in the wavelength range of 300 to 330 nm, and the maximum absorbance is 1 or more. Photosensitive composition.

2. The photosensitive resin (A) contains a resin having an epoxy group. The photosensitive composition of claim 1.

3. The acid anhydride (a3) ​​further contains an acid monoanhydride (a5). The photosensitive composition according to claim 1 or 2.

4. The acid dianhydride (a4) contains 3,3',4,4'-biphenyltetracarboxylic dianhydride. The photosensitive composition according to any one of claims 1 to 3.

5. the amount of the acid dianhydride (a4) is 0.01 mol or more and 0.24 mol or less relative to 1 mol of the epoxy compound (a1); The photosensitive composition according to any one of claims 1 to 4.

6. The photopolymerization initiator (B) contains at least one selected from the group consisting of an α-aminoalkylphenone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, and an oxime ester-based photopolymerization initiator. The photosensitive composition according to any one of claims 1 to 5.

7. The photopolymerizable compound (C) contains at least one of a difunctional unsaturated compound and a trifunctional unsaturated compound. The photosensitive composition according to any one of claims 1 to 6.

8. Further containing a solvent (E), The ratio of the solvent (E) is 50% by mass or more based on the photosensitive composition. The photosensitive composition according to any one of claims 1 to 7.

9. The solvent (E) contains an alcohol-based solvent (E1), The photosensitive composition according to claim 8.

10. The solvent (E) contains propylene glycol monomethyl ether. The photosensitive composition according to claim 8 or 9.

11. A cured product of the photosensitive composition according to any one of claims 1 to 10. Transparent cured film.

12. A substrate and the transparent cured film according to claim 11 overlying the substrate. Laminate.

13. A photosensitive composition according to any one of claims 1 to 10 is applied onto a substrate to form a dry film having a thickness dimension of 10 μm or less; The dried film is partially exposed to light and then developed with an alkaline developer to form a pattern, thereby producing a transparent cured film overlying the substrate. A method for manufacturing a laminate.

Images