JP2013231898A - Photosensitive resin composition, photosensitivity laminate, flexible circuit board, and perpetual pattern formation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition favorable for forming a cure film, such as a solder resist, presenting high insulation and excellent in bending resistance.SOLUTION: A photosensitive resin composition includes an acid modification ethylenically unsaturated group-containing polyurethane resin, a radical polymerizable compound, a thermal crosslinking agent, and a photoinitiator. The polyurethane resin is photosensitive resin composition including structures represented by general formulas (a1), (a2), and (a3). The general formula (a1) is -O-L(-R)-O-, where Lrepresents an organic group of 2+r valences, r represents an integer of 1-3, Rrepresents a group having ethylenically unsaturated group. The general formula (a2) is Y(-X-), where Xrepresents *-NH-C(=O)O- or *-OC(=O)NH-, where * represents a bond in a side connecting to Y. The general formula (a3) is -O-L-O-, where Lrepresents a divalent linking group of not having an ethylenically unsaturated group, a carboxyl group, and a siloxane structure.

Description

  The present invention relates to a photosensitive resin composition suitable as a solder resist material for a flexible circuit board, and a photosensitive laminate, a flexible circuit board, and a permanent pattern forming method using the photosensitive resin composition.

  As a method for forming a permanent pattern such as a solder resist, for example, a photosensitive resin composition is laminated on a substrate such as a copper-clad laminate on which a permanent pattern is formed using a screen printing machine or a roll coater. A method for forming a permanent pattern by forming a laminated body, exposing the photosensitive layer in the laminated body, developing the photosensitive layer after the exposure to form a pattern, and then performing a curing treatment, etc. Are known.

A solder resist formed on a flexible printed circuit board is required to have a high degree of insulation (folding resistance) as well as a high degree of insulation.
Patent Document 1 discloses a curable urethane resin obtained by reacting a specific terminal acid anhydride group-containing urethane prepolymer and a specific hydroxyl group-containing resin, and a cured film formed using the curable urethane resin. Is excellent in electrical insulation and the like.

JP 2010-150463 A

This invention makes it a subject to provide the photosensitive resin composition suitable for formation of cured films, such as a soldering resist which is excellent also in folding resistance, while showing a higher degree of insulation.
Another object of the present invention is to provide a photosensitive laminate, a flexible circuit board, and a permanent pattern forming method using the photosensitive resin composition.

The object of the present invention has been achieved by the following means.
<1> A photosensitive resin composition containing (A) an acid-modified ethylenically unsaturated group-containing polyurethane resin, (B) a radical polymerizable compound, (C) a thermal crosslinking agent, and (D) a photopolymerization initiator. And
The photosensitive resin composition in which the (A) polyurethane resin has a structure represented by the following general formula (a1), a structure represented by the following general formula (a2), and a structure represented by the following general formula (a3) object:

—O—L ^a1 (—R ^a1 ) _r —O— General formula (a1)
In the formula, L ^a1 represents a 2 + r-valent organic group. r shows the integer of 1-3. R ^a1 represents a group having an ethylenically unsaturated group;

Y ^a2 (-X ^a2- ) _b ... General formula (a2)
In the formula, X ^a2 represents * —NH—C (═O) O— or * —OC (═O) NH—, and “*” represents a bond on the side linked to Y ^a2 . Y ^a2 represents a b-valent linking group. b represents an integer of 3 or more;

-O-L ^a3 -O- General formula (a3)
In formula, ^La3 shows the bivalent coupling group which does not contain an ethylenically unsaturated group and a carboxyl group.
<2> ^{L a3} in formula _{(a3), - (CH 2} CH 2 O) n U1 CH 2 CH 2 -, - _[CH 2 CH _(CH 3) O] _{^{n U1 -CH 2 CH (CH 3}} ) _{-, - (CH 2 CH 2} CH 2 CH 2 O) n U1 -CH 2 CH 2 CH 2 CH 2 -, the structure represented by the following general formula (LL1), represented by the following general formula (LL2) structure The photosensitive resin composition according to <1>, which is a structure represented by the following general formula (LL3) or a structure represented by the following general formula (LL4):

Here, n ^{U1 to} n ^U4 , n and n ′ represent a number of 1 or more. R ^LL1 , R ^LL2 and R each represent a divalent chain hydrocarbon group or a divalent cyclic hydrocarbon group.
<3> The photosensitive resin composition according to <1> or <2>, in which the general formula (a1) is represented by the following general formula (a1-1) or the following general formula (a1-2):

In the formula, R ¹ , R ² and R ³ represent a hydrogen atom or a substituent. A represents a divalent organic group. X represents an oxygen atom, a sulfur atom or —N (R ¹² ) —, and R ¹² represents a hydrogen atom or a substituent.

In the formula, R ^a1-2 represents a hydrogen atom or methyl. L ^a1-2 represents a divalent organic group.
^<4> molecular weight of ^{L a3} is 400～8,000, <1> to the photosensitive resin composition according to any one of <3>.
<5> The molecular weight of the ^{L a3} in the general formula (a3) is 500 to 5,000, the photosensitive resin composition according to <4>.
<6> (A) The polyurethane resin has a mass average molecular weight of 5,000 to 60,000, an acid value of solid content of 10 to 120 mgKOH / g, and an ethylenically unsaturated group content of 0.05. The photosensitive resin composition of any one of <1>-<5> which is -1.2 mmol / g.
<7> (A) The photosensitive resin according to any one of <1> to <6>, wherein the polyurethane resin has 10 to 60% by mass of the structure represented by the general formula (a3) in the resin. Resin composition.
<8> (A) The polyurethane resin is at least one diisocyanate compound, at least one diol compound having an ethylenically unsaturated group and two hydroxyl groups, at least one diol compound having a carboxyl group and two hydroxyl groups, At least one diol compound having neither an ethylenically unsaturated group nor a carboxyl group, and three or more groups selected from a hydroxyl group and an isocyanate group, each having no ethylenically unsaturated group and a carboxyl group The photosensitive resin composition according to any one of <1> to <7>, which is a resin obtained by reacting a trifunctional or higher functional compound.
<9> The photosensitive resin composition according to <8>, wherein the diisocyanate compound has a 2,2-diphenylpropane type, diphenylmethane type, biphenyl type, naphthalene type, phenanthrene type, or anthracene type skeleton.
<10> The photosensitive laminated body which has a photosensitive layer containing the photosensitive resin composition of any one of <1>-<9> on a base material.
The flexible circuit board which has a resist pattern obtained by photocuring the photosensitive layer containing the photosensitive resin composition of any one of <1>-<9> on a <11> base material.
The flexible circuit board as described in <11> whose <12> base material is a polyimide film.
<13> A permanent pattern forming method including exposing a photosensitive layer formed using the photosensitive resin composition according to any one of <1> to <9>.

  In this specification, when there are a plurality of substituents, linking groups, ligands, etc. (hereinafter referred to as substituents) indicated by specific symbols, or a plurality of substituents etc. are specified simultaneously or alternatively. In some cases, each substituent group may be the same as or different from each other. The same applies to the definition of the number of substituents and the like. Further, when a plurality of substituents and the like are adjacent (particularly adjacent), they may be connected to each other or condensed to form a ring.

The photosensitive resin composition and the photosensitive laminate of the present invention can be suitably used for forming a cured film such as a solder resist that is excellent in both insulation and folding resistance.
The flexible circuit board of the present invention has a cured film such as a solder resist excellent in both insulation and folding resistance.
According to the method for forming a permanent pattern of the present invention, it is possible to form a cured film such as a solder resist excellent in both insulation and folding resistance.

(Photosensitive resin composition)
The photosensitive resin composition of the present invention comprises (A) a specific acid-modified ethylenically unsaturated group-containing polyurethane resin, (B) a radical polymerizable compound, (C) a thermal crosslinking agent, and (D) a photopolymerization initiator. contains.

<Acid-modified ethylenically unsaturated group-containing polyurethane resin>
The acid-modified ethylenically unsaturated group-containing polyurethane resin used in the present invention is an acid-modified polyurethane resin having an ethylenically unsaturated group in the side chain and a branched structure. In the present invention, the side chain is a chain branched from the chain of atoms constituting the main chain of the polyurethane resin, and having an ethylenically unsaturated group in the side chain means an ethylenically unsaturated group. Such side chains are included.
The ethylenically unsaturated group is a group having an ethylene bond that is consumed in the measurement of bromine value and iodine value, and is not a group showing aromaticity such as benzene. The ethylenically unsaturated group is preferably a vinyl group which may have a substituent.
Moreover, acid modification means having an acidic group in resin. Examples of the acidic group include a phosphoric acid group, a sulfonic acid group, a carboxyl group, a boric acid group, a sulfonamide group, and a phenolic hydroxyl group, and among them, a carboxyl group is more preferable.

  The preferred molecular weight, acid value, ethylenically unsaturated group content and solid content (nonvolatile component) concentration of the resin solution used in the present invention will be described below.

<< Molecular weight >>
The mass average molecular weight of the acid-modified ethylenically unsaturated group-containing polyurethane resin used in the present invention is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5,000 to 50,000, 000 to 40,000 is more preferable, and 5,000 to 30,000 is particularly preferable. When the weight average molecular weight is less than 5,000, when the photosensitive resin composition of the present invention is used for a photosensitive solder resist, sufficient strength of the cured film may not be obtained. If it exceeds 1, application suitability and developability may deteriorate. In addition, when an inorganic filler is used, it is excellent in the dispersibility of the inorganic filler, excellent in crack resistance and heat resistance, and excellent in developability of non-image areas with an alkaline developer.
Here, the mass average molecular weight is determined using, for example, a high-speed GPC apparatus (manufactured by Toyo Soda Co., Ltd., HLC-802A), a 0.5 mass% THF solution as a sample solution, and the column is TSKgel HZM-M 1 Using a book, 200 μL of sample can be injected, eluted with the THF solution, and measured at 25 ° C. with a refractive index detector or UV detector (detection wavelength 254 nm). And the mass mean molecular weight was calculated | required from the molecular weight distribution curve calibrated with the standard polystyrene.

<< Acid value >>
The acid value of the acid-modified ethylenically unsaturated group-containing polyurethane resin used in the present invention is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10 mgKOH / g to 120 mgKOH / g, 15 mgKOH / g -110 mgKOH / g is more preferable, and 20 mgKOH / g-90 mgKOH / g is particularly preferable. If the acid value is less than 10 mgKOH / g, the developability may be insufficient, and if it exceeds 120 mgKOH / g, the development rate may be too high, and the development may be difficult to control.
Here, the acid value can be measured in accordance with, for example, JIS K0070. In addition, when a sample does not melt | dissolve, a dioxane or tetrahydrofuran is used as a solvent. The acid value is the solid content acid value of the resin.

<< ethylenically unsaturated group content >>
There is no restriction | limiting in particular as ethylenically unsaturated group content of the acid-modified ethylenically unsaturated group containing polyurethane resin used for this invention, Although it can select suitably according to the objective, 0.05 mmol / g-2. 0 mmol / g is preferable, 0.3 mmol / g to 1.9 mmol / g is more preferable, 0.5 mmol / g to 1.8 mmol / g is further preferable, and 0.7 mmol / g to 1.8 mmol / g is further preferable In particular, it is particularly preferably 1.2 mmol / g or less. If the ethylenically unsaturated group content is less than 0.05 mmol / g, the heat resistance and plating solution resistance of the cured film may be inferior, and if it exceeds 2.0 mmol / g, folding resistance may deteriorate. There is.
Here, ethylenically unsaturated group content can be calculated | required by measuring a bromine number, for example. The bromine number can be measured, for example, according to JIS K2605.
Here, the ethylenically unsaturated equivalent is typically a vinyl group equivalent, and the number of grams of bromine (Br ₂ ) added to 100 g of the resin to be measured obtained by the bromine number (gBr ₂ / 100 g) is converted to the number of moles of added bromine (Br ₂ ) per 1 g of resin.

<< Solid content concentration of acid-modified ethylenically unsaturated group-containing polyurethane resin solution >>
The acid-modified ethylenically unsaturated group-containing polyurethane resin used in the present invention is usually synthesized and stored in a solution state. There is no restriction | limiting in particular in the solid content concentration of the polyurethane resin in the said solution, Although it can select suitably according to the objective, 10-90 mass% is preferable, 20-80 mass% is more preferable, 30-75 mass% Is more preferable, 40 to 75 mass% is more preferable, and 45 to 75 mass% is further preferable.
When there is too little content of the said solid content, the viscosity of the photosensitive resin composition prepared using the said resin solution will become inadequate, and printability may not be provided to the said composition. Moreover, when there is too much content of the said solid content, it will become high viscosity and will become agitating failure and it may not become a homogeneous resin solution.

  The acid-modified ethylenically unsaturated group-containing polyurethane resin used in the present invention will be described below.

  The acid-modified ethylenically unsaturated group-containing resin used in the present invention has a structure represented by the following general formula (a1).

—O—L ^a1 (—R ^a1 ) _r —O— General formula (a1)

In general formula (a1), L ^a1 represents a 2 + r-valent organic group. In general formula (a1), the oxygen atoms at both ends constitute a urethane bond. r shows the integer of 1-3. R ^a1 represents a group having an ethylenically unsaturated group. In the general formula (a1), —O—L ^a1 —O— constitutes the main chain of the polyurethane resin (however, a part of the structure in L ^a1 may constitute a side chain). R ^a1 is bonded to L ^a1 and constitutes a side chain of the polyurethane resin.
L ^a1 is preferably a group obtained by removing 2 + r hydrogen atoms from a saturated hydrocarbon having 3 to 30 carbon atoms, preferably 3 to 25 carbon atoms, more preferably 3 to 10 carbon atoms. The saturated hydrocarbon may have a linear structure, a branched structure, or a cyclic structure. The saturated hydrocarbon has an arylene group, an ether bond (—O—), an imino bond (—NH—), an amide bond (—CONH—), an ester bond (—COO— or —OCO—) in the chain. Even if a sulfonamide bond (—NHSO ₂ — or —SO ₂ NH—), a urethane bond (—NHCOO— or —OCONH—), a ureylene bond (—NHCONH—), a carbonate bond (—OCOO—) or the like is present Good. Examples of the saturated hydrocarbon include propane, 2-methylpropane, butane, pentane, hexane, heptane, octane, and cyclohexane.
R ^a1 preferably has at least one of the groups represented by the following general formulas (1) to (3).

In the general formula (1), R ^{1 to} R ³ represent a hydrogen atom or a monovalent organic group. Here, examples of the monovalent organic group include a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an alkylthio group, and an arylthio group. , Amino group, alkylamino group, arylamino group, acylamino group, sulfonamido group, alkyl or arylsulfonyl group, alkyl or arylsulfinyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group, acyloxy group, carbamoyl group, sulfamoyl Group, hydroxyl group, mercapto group, cyano group, nitro group, carboxyl group, sulfo group, ureido group, urethane group and the like, and these groups may be further substituted with these substituents. In addition, the same group is mentioned also in each subsequent group and the monovalent organic group or substituent in each general formula.
R ¹ is preferably a hydrogen atom or an alkyl group which may have a substituent. Among them, a hydrogen atom or a methyl group is more preferable in terms of high radical reactivity. R ² and R ³ have a hydrogen atom, a halogen atom, an amino group, a carboxyl group, an alkoxycarbonyl group, a sulfo group, a nitro group, a cyano group, an alkyl group that may have a substituent, or a substituent. An aryl group which may have a substituent, an aryloxy group which may have a substituent, an alkylamino group which may have a substituent, an aryl which may have a substituent An amino group, an alkylsulfonyl group which may have a substituent, and an arylsulfonyl group which may have a substituent are preferable. Among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, a substituent is preferable because of high radical reactivity. An alkyl group which may have a group and an aryl group which may have a substituent are more preferable.

X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —, and R ¹² represents a hydrogen atom or a monovalent organic group. R ¹² is preferably an alkyl group which may have a substituent, and among them, a hydrogen atom, a methyl group, an ethyl group, and an isopropyl group are more preferable in terms of high radical reactivity.
Here, the substituent that each of the above groups may have (substituent that may be present in an alkyl group that may have a substituent) is not particularly limited, and may be appropriately selected depending on the purpose. For example, the groups mentioned in the above-mentioned monovalent organic groups can be mentioned, and halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups Amino group, alkylamino group, arylamino group, acylamino group, carbamoyl group, alkoxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, carboxyl group, sulfo group, nitro group, and cyano group are preferred.

In General formula (2), R < ⁴ > -R < ⁸ > shows a hydrogen atom or monovalent organic group. R ^{4 to} R ⁸ are not particularly limited and may be appropriately selected depending on the intended purpose. Here, as a monovalent organic group, the group quoted by R < ¹ > -R < ³ > in the said General formula (1) is mentioned. R ^{4 to} R ⁸ are a hydrogen atom, a halogen atom, an amino group, an alkylamino group which may have a substituent, a dialkylamino group which may have a substituent, or an arylamino which may have a substituent. Group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group which may have a substituent, aryl group which may have a substituent, alkoxy group which may have a substituent , An aryloxy group which may have a substituent, an alkylsulfonyl group which may have a substituent, and an arylsulfonyl group which may have a substituent are preferable. An atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group which may have a substituent, and an aryl group which may have a substituent are more preferable.

Examples of the substituent that each of the above groups may have include the same as those in the general formula (1).
Y represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² has the same meaning as R ^{12 in} the general formula (1), and preferred examples thereof are also the same.

In General formula (3), R < ⁹ > -R < ¹¹ > shows a hydrogen atom or monovalent organic group. Here, as a monovalent organic group, the group quoted by R < ¹ > -R < ³ > in the said General formula (1) is mentioned. R ⁹ is preferably a hydrogen atom or an alkyl group which may have a substituent. Among them, a hydrogen atom or a methyl group is more preferable in terms of high radical reactivity. R ¹⁰ and R ¹¹ are a hydrogen atom, a halogen atom, an amino group, an alkylamino group which may have a substituent, a dialkylamino group which may have a substituent, or an arylamino which may have a substituent. Group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group which may have a substituent, aryl group which may have a substituent, alkoxy group which may have a substituent An aryloxy group which may have a substituent, an alkylsulfonyl group which may have a substituent, and an arylsulfonyl group which may have a substituent are preferable. Among these, from the viewpoint of high radical reactivity, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group that may have a substituent, and an aryl group that may have a substituent are more preferable.

Here, as a substituent which each said group may have, the thing similar to General formula (1) is mentioned.
Z represents an oxygen atom, a sulfur atom, —N (R ¹³ ) —, or an optionally substituted phenylene group. R ¹³ represents a hydrogen atom or a monovalent organic group. R ¹³ is preferably an alkyl group which may have a substituent, and among them, a methyl group, an ethyl group, and an isopropyl group are more preferable in terms of high radical reactivity.

R ^a1 in the general formula (a1) preferably has a group represented by the general formula (1) among the groups represented by the general formulas (1) to (3). Further, from the viewpoint of forming a crosslinked cured film, a group in which R ¹ in the general formula (1) is a methyl group and R ² and R ³ are hydrogen atoms, and R ^{1 to} R ³ in the general formula (1) are all. It is preferable to have a group that is a hydrogen atom or a styryl group in which Z in the general formula (3) is a phenylene group. More preferably, ^{R a1} in formula (a1) has the general formula (1) groups ^{R 1} in is ^{R 2} and ^{R 3} are hydrogen atom a methyl group or ^R 1 to R ³ in the general formula (1), All have groups that are hydrogen atoms. More preferably, in terms of compatibility between storage stability and formation of cross-linked cured film, the R ^a1 in formula (a1) R ¹ in the general formula (1) is a methyl group and R ² and R ³ are hydrogen atoms A group which is
X in the general formula (1) is preferably an oxygen atom, and the group having an ethylenically unsaturated group is preferably a methacryloyloxy group or an acryloyloxy group, and more preferably a methacryloyloxy group.

Examples of a method for preparing a polyurethane resin having a structure represented by the general formula (a1) include (i) a method of polymerizing a diol compound having an ethylenically unsaturated group and a diisocyanate compound, and (ii) a carboxyl group. A method of reacting a compound having an epoxy group and an ethylenically unsaturated group in the molecule after polymerizing the containing diol and the diisocyanate compound is mentioned.
Hereinafter, the polyurethane resin obtained by the method (i) is also referred to as polyurethane resin (i), and the polyurethane resin obtained by the method (ii) is also referred to as polyurethane resin (ii). Further, in this specification, the term “polyurethane resin having an ethylenically unsaturated group in the side chain” is used as a concept including at least both polyurethane resins (i) and (ii).
In the present invention, the polyurethane resin (i) can be suitably used.

-Polyurethane resin (i)-
The polyurethane resin (i) is a basic skeleton composed of a reaction product of at least one diisocyanate compound represented by the following general formula (4) and at least one diol compound represented by the following general formula (5). A polyurethane resin having

OCN-X ⁰ -NCO ... General formula (4)
HO-Y ⁰ -OH General formula (5)

In the general formula (4), X ⁰ and Y ⁰ represent a divalent group.
When a diol compound in which Y ^{0 in the} general formula (5) is -L ^a1 (—R ^a1 ) _r — in the general formula (a1) is used, a polyurethane resin having a structure represented by the general formula (a1) is obtained. It is done.

Here, as the diol compound in which Y 2 ^O in the general formula (5) is —L ^a1 (—R ^a1 ) _r — in the general formula (a1), for example, commercially available like trimethylolpropane monoallyl ether is available. And compounds such as halogenated diol compounds, triol compounds, aminodiol compounds, and compounds containing unsaturated groups, such as carboxylic acids, acid chlorides, isocyanates, alcohols, amines, thiols, and halogenated alkyl compounds The compound manufactured by reaction of these is mentioned.
Y ^O in the general formula (5) is, ^-L a1 ^(-R _{a1) r} in formula (a1) - The a is diol compound, more specifically, the following formula (UE-1) ~ (UE- The diol compound represented by 7) is mentioned.

In General Formulas (UE-1) to (UE-7), E ¹ represents a single bond or a divalent linking group (a divalent organic residue), and E ² represents a single bond or ₂ other than —CH ₂ —. A valent linking group is shown. A represents a divalent linking group. Q represents any group of the general formulas (1) to (3). Examples of the divalent linking group for E ¹ and E ² include —O—, —S—, —OCH (CH ₂ —Q) CH ₂ —, —CO ₂ —CH ₂ —, —OCH ₂ C (CH _{2 -Q) 2 CH 2 -,} - O-CONHCH 2 CH 2 -, - OC (= O) -, - CONHCH 2 CH 2 -, - CH 2 C (CH 2 -Q) 2 CH 2 -, - CH _{2 -, - NHCONHCH 2 CH 2} -, - NHCH (CH 2 -Q) CH 2 -, - NCH (CH 2 -Q) CH 2 -, - NHCH 2 C (CH 2 -Q) 2 CH 2 -, - _{NH-CH (CH 2 -Q)} CH 2 -, - C (= O) -, - CO 2 -CH 2 CH 2 -, - CO 2 -CH 2 CH 2 CH 2 - and the like. Here, Q represents any group of the general formulas (1) to (3).
Specific examples of these compounds include compounds described in paragraphs “0057” to “0060” of JP-A-2005-250438.

  In the polyurethane resin used in the present invention, the structure represented by the general formula (a1) is preferably a structure represented by the following general formula (a1-1) or (a1-2), The structure represented by 1) is particularly preferable.

In general formula (a1-1), R ¹ , R ² and R ³ represent a hydrogen atom or a substituent. A represents a divalent organic group. X represents an oxygen atom, a sulfur atom or —N (R ¹² ) —, and R ¹² represents a hydrogen atom or a substituent.
^{R 1,} R 2, ^{R 3} and X in the preferred embodiment of the units represented by general formula (a1-1) is the same meaning as ^{R 1,} R 2, ^{R 3} and X in the general formula (1).

  The polyurethane resin having the structure represented by the general formula (a1-1) includes a diol compound represented by the following general formula (a1-1) ′ and a diisocyanate compound represented by the general formula (4). It can be obtained by reaction.

In general formula (a1-1) ′, A, X, R ¹ , R ² and R ³ have the same meaning as in general formula (a1-1). Examples of the compound represented by the general formula (a1-1) ′ include compounds described in paragraphs [0064] to [0066] of JP-A-2005-250438, and can be suitably used in the present invention.
By using a polyurethane resin comprising the diol compound represented by the general formula (a1-1) ′ as a constituent component, excessive molecular motion of the polymer main chain caused by the secondary alcohol having a large steric hindrance can be suppressed, and the layer It is considered that an improvement in coating strength can be achieved.

In general formula (a1-2), R ^a1-2 represents a hydrogen atom or methyl. L ^a1-2 represents a divalent organic group not containing —NHC (═O) — and —C (═O) NH—.

In general formula (a1-2), L ^a1-2 is preferably an alkylene group having 1 to 20 carbon atoms, an arylene group, or a combination thereof. The alkylene group may have a straight chain structure, a branched structure, or a cyclic structure. Moreover, you may have substituents, such as a halogen atom.
When L ^a1-2 has an alkylene group having 1 to 20 carbon atoms, the alkylene group is preferably unsubstituted. The alkylene group preferably has 1 to 20 carbon atoms, more preferably 2 to 10 carbon atoms. Specific examples of the alkylene group include ethylene, propylene, butylene, pentylene, hexylene and the like.
When L ^a1-2 has an arylene group, the number of carbon atoms of the arylene group is preferably an integer of 6 to 30, and more preferably 6 to 20. The arylene group includes a structure in which the arylene group is linked by a single bond. Specific examples of the arylene group include phenylene, biphenylene, naphthylene, and the like, which may have a substituent.
In the case where L ^a1-2 is an alkylene group, an arylene group, or a combination thereof, a carbonyl (C═O), an imino bond (—NH—), an ester bond ( -COO- or -OCO-), an ether bond (-O-) sulfonamide linkage (-NHSO ₂ - or _-SO 2 NH-), a carbonate bond (-OCOO-), or a group having a heterocyclic ring (specifically , A group obtained by removing two hydrogen atoms from a heterocyclic ring such as triazine, isocyanuric acid, and piperazine) may be interposed or bonded as a bonding group. Among these, ^La1-2 has an unsubstituted alkylene group having 2 to 6 carbon atoms, or an unsubstituted alkylene group having 4 to 9 carbon atoms including an ether bond (—O—) as a linking group, and a substituent. A phenylene group is preferred.

  The polyurethane resin having the structure represented by the general formula (a1-2) can be obtained, for example, by reacting the following diol compound with the diisocyanate compound represented by the general formula (4).

  The polyurethane resin used in the present invention has a branched structure by having a structure represented by the following general formula (a2).

Y ^a2 (-X ^a2- ) _b ... General formula (a2)

In the formula, X ^a2 represents * —NH—C (═O) O— or * —OC (═O) NH—, and “*” represents a bond on the side linked to Y ^a2 . All X ^a2 are linked to Y ^a2 . Y ^a2 represents a b-valent linking group that does not contain an ethylenically unsaturated group and a carboxyl group. b represents an integer of 3 or more.
X ^a2 is preferably linked to a polymer residue at a bond other than the bond linked to Y ^a2 . This polymer residue is preferably a polyurethane residue. The polyurethane residue may also have a branch due to the structure represented by the general formula (a2).

In general formula (a2), Y ^a2 is a hydrocarbon having 3 to 30 carbon atoms, more preferably 3 to 25 carbon atoms, still more preferably 3 to 10 carbon atoms, or a carbonyl group (C═O) in the hydrocarbon chain. , Ether bond (—O—), imino bond (—NH—), amide bond (—CONH—), ester bond (—COO— or —OCO—), sulfonamide bond (—NHSO ₂ — or —SO ₂ NH) It is preferably a group in which three hydrogen atoms are removed from those intervened by-), carbonate bond (-OCOO-), thiophosphate bond [-OP (= S) (O-) ₂ ] and the like. The hydrocarbon may have a straight chain structure, a branched structure, or a cyclic structure. The hydrocarbon is preferably a saturated hydrocarbon, and examples of the saturated hydrocarbon include propane, butane, pentane, hexane, heptane, octane, cyclohexane, 2-methylpropane, 2-ethylpropane, 2,2 -Dimethylpropane, 2,2-diethylpropane, 2-methyl-2-ethylpropane.

  Although the polyurethane resin used for this invention has a structure represented by the said general formula (a2), it is preferable that these content is 0.1-5 mass% in the total weight of a polyurethane resin.

As a raw material for introducing the structure of the general formula (a2), triol and / or triisocyanate is preferably used, and triol is more preferably used. That is, the structure of the general formula (a2) is a structure obtained when the polyurethane resin has triol and / or triisocyanate as a constituent component, and preferably a structure obtained by having triol as a constituent component.
Although the compound of the following structure is mentioned as the said triol and triisocyanate, This invention is not limited to these. The raw material for introducing the structure of the general formula (a2) is 0.1 to 20 mol with respect to 100 mol of the total amount of starting materials used for the synthesis of the polyurethane resin (that is, the total amount of polyol + polyisocyanate). It is preferably 0.5 to 15 mol, more preferably 1 to 10 mol, and particularly preferably 1 to 5 mol.

  The polyurethane resin used in the present invention is acid-modified, and examples of the acid in this acid modification include carboxylic acid and sulfonic acid, and carboxylic acid is particularly preferable. For the synthesis of the polyurethane resin (i), it is preferable to use acid-modified by using a diol compound having a carboxyl group. Examples of the diol compound having a carboxyl group include those represented by the following formulas (17) to (19).

In the formulas (17) to (19), R ¹⁵ represents a hydrogen atom or a substituent (for example, a cyano group, a nitro group, a halogen atom such as —F, —Cl, —Br, —I, etc.), —CONH ₂ , —COOR ¹⁶ , —OR ¹⁶ , —NHCONHR ¹⁶ , —NHCOOR ¹⁶ , —NHCOR ¹⁶ , —OCONHR ¹⁶ (wherein R ¹⁶ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group having 7 to 15 carbon atoms. ) And the like, as long as it is an alkyl group, an aralkyl group, an aryl group, an alkoxy group, or an aryloxy group that may have a), may be appropriately selected according to the purpose. A hydrogen atom, an alkyl group having 1 to 8 carbon atoms, and an aryl group having 6 to 15 carbon atoms are preferable. In the formulas (17) to (19), L ⁹ , L ¹⁰ and L ¹¹ may be the same or different from each other, and may be a single bond or a substituent (for example, an alkyl group, an aralkyl group or an aryl group). As long as it is a divalent aliphatic or aromatic hydrocarbon group that may have an alkyl group, an alkoxy group, or a halogen atom. A C1-C20 alkylene group and a C6-C15 arylene group are preferable, and a C1-C8 alkylene group is more preferable. If necessary, the L ^{9 to} L ¹¹ may have another functional group that does not react with the isocyanate group, for example, a carbonyl group, an ester group, a urethane group, an amide group, a ureido group, or an ether group. In addition, you may form a ring by two or three of said R < ¹⁵ >, L < ⁹ >, L < ¹⁰ >, L < ¹¹ >.
In the formula (18), Ar is not particularly limited as long as it is a trivalent aromatic hydrocarbon group which may have a substituent, and can be appropriately selected according to the purpose. Several to 15 aromatic groups are preferred.

  The diol compound having a carboxyl group represented by the formulas (17) to (19) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, 3,5-dihydroxybenzoic acid, 2, 2-bis (hydroxymethyl) propionic acid, 2,2-bis (2-hydroxyethyl) propionic acid, 2,2-bis (3-hydroxypropyl) propionic acid, bis (hydroxymethyl) acetic acid, bis (4-hydroxy Phenyl) acetic acid, 2,2-bis (hydroxymethyl) butyric acid, 4,4-bis (4-hydroxyphenyl) pentanoic acid, tartaric acid, N, N-dihydroxyethylglycine, N, N-bis (2-hydroxyethyl) -3-carboxy-propionamide and the like. These may be used individually by 1 type and may use 2 or more types together.

  There is no restriction | limiting in particular as a diol compound which has a carboxyl group, According to the objective, it can select suitably, For example, the compound described in Paragraph [0047] of Unexamined-Japanese-Patent No. 2007-2030 etc. are mentioned.

  The presence of such a carboxyl group is preferable because the polyurethane resin can be provided with characteristics such as hydrogen bonding properties and alkali solubility. By introducing a carboxyl group in this way, the acid value can be adjusted to the preferred range in the present invention as described above.

Moreover, in the synthesis | combination of the polyurethane resin which has an ethylenically unsaturated group in a side chain, the compound which ring-opened tetracarboxylic dianhydride with the diol compound other than the diol compound mentioned above can also be used together.
The compound obtained by ring-opening the tetracarboxylic dianhydride with a diol compound is not particularly limited and may be appropriately selected depending on the intended purpose. For example, JP-A-2005-250438, paragraph [0095] to And the compounds described in [0101].

  In preparation of the polyurethane resin used in the present invention, at least a diol compound represented by the following general formula (a3) 'is copolymerized in addition to the diol compound described above. By copolymerizing a diol compound of the following general formula (a3) ', the polyurethane resin used in the present invention has a structure represented by the following general formula (a3).

-O-L ^a3 -O- General formula (a3)
HO-L ^a3 —OH ... General formula (a3) ′

In General Formula (a3) and General Formula (a3) ′, L ^a3 represents a divalent linking group that does not contain an ethylenically unsaturated group and a carboxyl group.

L ^a3 includes, for example, an alkylene group, an arylene group, and a divalent heterocyclic group, and the alkylene group includes —O—, —OCOO—, a phenylene group, and —OCO—Z ¹ — in the chain of the alkylene group. COO— (Z ¹ represents an alkylene group, an alkenylene group, or an arylene group) may be included.

Among the diol compounds represented by the general formula (a3) ′, as the low-molecular diol compounds, those having a mass average molecular weight of less than 400 are preferable, and for example, described in paragraph [0048] of JP-A-2007-2030 And the like, and the like.
In the present invention, a polymer diol compound is preferable and will be described in detail below.

-Polymer diol compound-
The polymer diol compound is not particularly limited and may be appropriately selected depending on the intended purpose. For example, polyethylene glycol, polypropylene glycol, polyethylene oxide, polypropylene oxide, ethylene oxide / propylene oxide block copolymer or random copolymer Polyether diols such as coalesced polytetramethylene glycol, block copolymer or random copolymer of tetramethylene glycol and neopentyl glycol; polyhydric alcohol or polyether diol and maleic anhydride, maleic acid, fumaric acid, Polyester diols that are condensates of polybasic acids such as itaconic anhydride, itaconic acid, adipic acid, terephthalic acid, isophthalic acid; reaction of glycol or bisphenol with carbonate Alternatively, polycarbonate diols obtained by reacting phosgene with glycol or bisphenol in the presence of alkali; caprolactone-modified polymer diols such as caprolactone-modified polytetramethylene diol, polybutadiene-based polymers such as polyolefin-based polymer diols and hydrogenated polybutadiene diols Examples thereof include polymer diols and silicone polymer diols. These may be used alone or in combination of two or more.

In the present invention, preferred forms of L ^{a3 in} the general formulas (a3) and (a3) ′ are — (CH ₂ CH ₂ O) n ^U1 CH ₂ CH ₂ —, — [CH ₂ CH (CH ₃ ) O ] _{^{n U1 -CH 2 CH (CH 3}} ) -, - (CH 2 CH 2 CH 2 CH 2 O) n U1 -CH 2 CH 2 CH 2 CH 2 -, the structure represented by the following general formula (LL1), A structure represented by the following general formula (LL2), a structure represented by the following general formula (LL3), or a structure represented by the following general formula (LL4).

Here, R ^LL1 , R ^LL2, and R represent a divalent chain hydrocarbon group or a divalent cyclic hydrocarbon group. n ^{U1 to} n ^U4 , n and n ′ represent a number of 1 or more.
As the divalent chain hydrocarbon group, an alkylene group, an alkenylene group or an alkynylene group is preferable. These may have a branched or substituted group. More preferable carbon number is 2-8, ethylene group, trimethylene group, propylene group, tetramethylene group, 2-methyl-tetramethylene group, pentamethylene group, hexamethylene group, octamethylene group, 2-butenylene group, A 2-butynylene group is a suitable example.
The divalent cyclic hydrocarbon group is preferably a 5-membered ring, a 6-membered ring or a 7-membered ring, more preferably a 5-membered ring or a 6-membered ring, and even more preferably a 6-membered ring. . A single ring or a condensed ring may be used, and a single ring is preferable. Either an aromatic ring or an aliphatic ring may be used. Among these, preferred examples of the aromatic ring include a benzene ring and a naphthalene ring, and preferred examples of the aliphatic ring include a cyclohexane ring and a bicyclo [2.2.2] octane ring.

  The polyether diol compound is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include compounds described in paragraphs [0068] to [0076] of JP-A-2005-250438. Can be mentioned.

  The polyester diol compound is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include paragraphs [0077] to [0079] and paragraphs [0083] to [0085] of JP-A-2005-250438. No. 1-No. 8 and no. 13-No. 18 and the like, and the like.

  There is no restriction | limiting in particular as said polycarbonate diol compound, According to the objective, it can select suitably, For example, Unexamined-Japanese-Patent No. 2005-250438 Paragraph [0080]-[0081] and Paragraph [0084] No. 9-No. 12 and the like, and the like.

In addition to the diol compound described above, a diol compound having a substituent that does not react with an isocyanate group can be used in combination.
There is no restriction | limiting in particular as a diol compound which has a substituent which does not react with the said isocyanate group, According to the objective, it can select suitably, For example, Paragraph [0087]-[0088] of Unexamined-Japanese-Patent No. 2005-250438 And the described compounds.

The mass average molecular weight of such a polymer diol compound is preferably 400 to 8,000, more preferably 500 to 5,000, still more preferably 600 to 3,000, and 800 to 2 Is particularly preferred. If the mass average molecular weight is less than 400, sufficient folding resistance may not be obtained, and if it exceeds 8,000, the glass transition temperature (Tg) of the resulting polyurethane resin will be too low. May deteriorate.
Here, the mass average molecular weight is a high-speed GPC apparatus (HLC-802A, manufactured by Toyo Soda Co., Ltd.), a 0.5 mass% THF solution is used as a sample solution, and one TSKgel HZM-M column is used. Then, 200 μL of sample is injected, eluted with the THF solution, and measured at 25 ° C. with a refractive index detector or a UV detector (detection wavelength 254 nm).

  The mass ratio of the partial structure represented by the general formula (a3) in the acid-modified ethylenically unsaturated group-containing polyurethane resin is preferably 10 to 60%, more preferably 15 to 60%, and more preferably 20 to 20%. It is more preferable that it is 55%, and it is further more preferable that it is 30 to 50%. When the mass ratio is less than 10%, it may be difficult to suppress warping after curing, and when it exceeds 60%, the sensitivity of photocuring may be excessively lowered and resolution may be deteriorated.

As the polyurethane resin used in the present invention, those having at least one carboxyl group at the end of the polymer main chain are also preferably used because they are excellent in developability of non-image areas with an alkaline developer. It has at least one carboxyl group at the terminal of the polymer main chain and preferably has 2 or more and 5 or less carboxyl groups, and having two carboxyl groups is excellent in developability and has a fine pattern forming property. Is particularly preferable.
The polyurethane resin has two main chain ends, but preferably has at least one carboxyl group at one end, and may have at least one carboxyl group at both ends.

  You may have the structure represented by the following general formula (AD) at the terminal of the principal chain of the polyurethane resin.

General formula (AD)
-L ^100- (COOH) _n

In the general formula (AD), L ¹⁰⁰ represents an (n + 1) -valent organic linking chain, n represents an integer of 1 or more, preferably 1 to 5, and particularly preferably 2.
The organic linking group represented by L ¹⁰⁰ includes one or more atoms selected from a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom. Specifically, the organic linking group represented by L ¹⁰⁰ 1-30 are preferable, as for the number of atoms which comprises the main skeleton of a coupling group, 1-25 are more preferable, 1-20 are still more preferable, and 1-10 are especially preferable.
The “main skeleton of the organic linking group” means an atom or an atomic group used only for linking the main chain of the polyurethane resin and the terminal COOH, and when there are a plurality of linking paths, The atom or atomic group which comprises the path | route with the fewest number of atoms used is pointed out.

  The method for introducing at least one carboxyl group at the end of the main chain of the polyurethane resin is not particularly limited and may be appropriately selected depending on the intended purpose. For example, as a raw material for producing a polyurethane resin, at least one Examples include a method using a carboxylic acid compound having a carboxyl group.

  Examples of the carboxylic acid compound include a monocarboxylic acid compound having one carboxyl group, a dicarboxylic acid compound having two carboxyl groups, a tricarboxylic acid compound having three carboxyl groups, a tetracarboxylic acid compound having four carboxyl groups, and a carboxyl group. Examples thereof include pentacarboxylic acid compounds having five groups. Among these, a dicarboxylic acid compound having two carboxyl groups is particularly preferable in terms of excellent developability and fine pattern formability.

  The carboxylic acid compound is not particularly limited as long as it has at least one carboxyl group, and can be appropriately selected according to the purpose. However, a compound represented by the following general formula (ADH) is preferable.

General formula (ADH)
^{H-O-L 200 -Y 100} -L 100 - (COOH) n

In the general formula (ADH), L ¹⁰⁰ and n represent the same meaning as in the general formula (AD). Y ¹⁰⁰ represents a divalent or higher valent atom. L ²⁰⁰ represents a single bond or an alkylene group which may have a substituent.
Examples of the divalent or higher atom in Y ¹⁰⁰ include an oxygen atom, a nitrogen atom, a carbon atom, and a silicon atom. Among these, a nitrogen atom and a carbon atom are particularly preferable. Here, the atom represented by Y ¹⁰⁰ being divalent or more means that at least Y ¹⁰⁰ has two bonds in which the terminal —COOH is bonded via L ¹⁰⁰ and L ^{200. 100} may further have a hydrogen atom or a substituent.
Examples of the substituent which can be introduced into Y ^100, a hydrogen atom, an oxygen atom, a sulfur atom, a substituted group configured to include an atom selected from a nitrogen atom and a halogen atom. Among these, a hydrocarbon group having 1 to 50 carbon atoms is preferable, a hydrocarbon group having 1 to 40 carbon atoms is more preferable, and a hydrocarbon group having 1 to 30 carbon atoms is particularly preferable.

The alkylene group for L ^200, preferably an alkylene group having 1 to 20 carbon atoms, more preferably an alkylene group having 2 to 10 carbon atoms. Examples of the substituent that can be introduced into the alkylene group include a halogen atom (—F, —Br, —Cl, —I), an alkyl group that may have a substituent, and the like.

  The carboxylic acid compound represented by the general formula (ADH) is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include lactic acid, malic acid, hydroxyhexanoic acid, citric acid, and a diol compound. Examples include a reaction product of an acid anhydride. These may be used individually by 1 type and may use 2 or more types together. Among these, malic acid is particularly preferable.

  As a diisocyanate compound used for preparation of the polyurethane resin used for this invention, it can select suitably according to the objective besides the thing mentioned above, For example, the diisocyanate compound represented by following General formula (6) can be used. .

OCN-L ¹ -NCO General formula (6)

In the general formula (6), L ¹ represents a divalent aliphatic or aromatic hydrocarbon group which may have a substituent. If necessary, L ¹ may have another functional group that does not react with an isocyanate group, for example, an ester group, a urethane group, an amide group, or a ureido group.

  There is no restriction | limiting in particular as a diisocyanate compound represented by the said General formula (6), According to the objective, it can select suitably, For example, the dimer of 2, 4- tolylene diisocyanate and 2, 4- tolylene diisocyanate 2,6-tolylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3'-dimethylbiphenyl-4,4 ' Aromatic diisocyanate compounds such as diisocyanates; aliphatic diisocyanate compounds such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, dimer acid diisocyanate; isophorone diisocyanate, 4,4′-methyl Alicyclic diisocyanate compounds such as bis (cyclohexyl isocyanate), methylcyclohexane-2,4 (or 2,6) diisocyanate, 1,3- (isocyanatomethyl) cyclohexane; 1 mol of 1,3-butylene glycol and tolylene diisocyanate 2 A diisocyanate compound which is a reaction product of a diol such as an adduct with a mole and a diisocyanate;

The diisocyanate compounds represented by the general formula (4) or (6) may be used in combination with different types, but at least one of them should be an aromatic diisocyanate compound in terms of improving folding resistance. Is preferred. Examples of the aromatic diisocyanate compound include bisphenol A type (hereinafter also referred to as 2,2-diphenylpropane type), bisphenol F type (hereinafter also referred to as diphenylmethane type), biphenyl type, naphthalene type, phenanthrene type, or A diisocyanate compound having an anthracene skeleton is preferable, and a diisocyanate compound having a bisphenol A type or bisphenol F type skeleton is more preferable.
Each of these types of skeletons is represented by the following general formula.

In the above, R ^<a> , R ^<b > shows a substituent and as a substituent, a C2-C5 alkyl group is preferable. l ₁ and l _{2 each} represents an integer of 0 to 4. l ₁ and l ₂ are preferably 0 or 1. l ₃ represents an integer of 0-6. l ₄ represents an integer of 0 to 8. l ₃ is preferably 0 to 2, and l ₄ is preferably 0 or 2. When l _{1 to} l ₄ is 2 or more, a plurality of R ^a and R ^b may be the same as or different from each other.

  The diisocyanate compound is more preferably combined with an aromatic diisocyanate compound and an aliphatic diisocyanate compound from the viewpoint of suppressing warping after curing and improving folding resistance. The aromatic diisocyanate compound is preferably a diisocyanate compound having a bisphenol A-type, bisphenol F-type, biphenyl-type, naphthalene-type, phenanthrene-type, or anthracene-type skeleton, such as a bisphenol A-type or bisphenol F-type skeleton. The diisocyanate compound is more preferable. As the aliphatic diisocyanate compound, for example, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate and dimer acid diisocyanate are preferable, and hexamethylene diisocyanate and trimethylhexamethylene diisocyanate are more preferable.

In the polyurethane resin having an ethylenically unsaturated group in the side chain used in the present invention, the diisocyanate compound and the diol compound are added to an aprotic solvent with a known catalyst having an activity corresponding to the respective reactivity, and heated. To be synthesized. The molar ratio of the diisocyanate used in the synthesis and the diol compound: As the _(M a M _b), is not particularly limited and may be appropriately selected depending on the intended purpose, 1: 1.2 to 1.2: 1 Preferably, by treatment with alcohols or amines, a product having desired physical properties such as molecular weight or viscosity is finally synthesized in a form in which no isocyanate group remains.

  The polyurethane resin having an ethylenically unsaturated group in the side chain used in the present invention is, in particular, the aforementioned diisocyanate compound and a diol compound, a (meth) acrylate compound having two hydroxyl groups in the molecule, and two in the molecule. It is preferably obtained by reacting a carboxylic acid having a hydroxyl group and the above-mentioned polymer diol compound, and in addition to this, obtained by reacting a compound having one hydroxyl group and a carboxyl group represented by the general formula (ADH). Also good.

-Polyurethane resin (ii)-
The polyurethane resin (ii) is a polyurethane resin obtained by reacting a carboxyl group-containing polyurethane with a compound having an epoxy group and an ethylenically unsaturated group in the molecule. More specifically, the polyurethane resin (ii) comprises a carboxyl group-containing polyurethane resin obtained by polymerizing diisocyanate and a carboxyl group-containing diol, and a compound having an epoxy group and an ethylenically unsaturated group in the molecule. It is a polyurethane resin obtained by reaction. In order to make the polyurethane resin (ii) a polyurethane resin as defined in the present invention, the diol compound and diisocyanate compound described in the above-mentioned polyurethane resin (i) are appropriately used as raw materials when preparing the polyurethane resin (ii). Used as
In the preparation of the polyurethane resin (ii), compounds represented by the following general formulas (IV-1) to (IV-16) can be used as compounds having an epoxy group and an ethylenically unsaturated group in the molecule.

In General Formulas (IV-1) to (IV-16), R ₁₄ represents a hydrogen atom or a methyl group, R ₁₅ represents an alkylene group having 1 to 10 carbon atoms, and R ₁₆ represents 1 to 1 carbon atoms. 10 hydrocarbon groups are shown. p shows 0 or the integer of 1-10.

In addition, when a carboxyl group-containing polyurethane and a compound having an epoxy group or oxetane group in the molecule are reacted, a partial structure in which X, Y, or Z is connected to the polyurethane main chain has -CO _2- (β-position or γ It has a structure having an aliphatic group)-(*) substituted with a hydroxyl group or an acyloxy group at the position. Here, the partial structures of the general formulas (1) to (3) exist on the (*) side.

In addition, the polyurethane resin (ii) may further be copolymerized with a low molecular weight diol having a carboxyl group-free mass average molecular weight of 500 or less. The carboxyl group-free low molecular weight diol can be added as long as the alkali solubility is not lowered and the elastic modulus of the cured film can be kept sufficiently low.
As said low molecular weight diol compound, the compound described in the paragraph [0048] of Unexamined-Japanese-Patent No. 2007-2030 etc. are mentioned, for example.

  These high molecular compounds may be used individually by 1 type, and may use 2 or more types together.

  Also in the polyurethane resin (ii), those having at least one carboxyl group at the terminal of the polymer main chain are preferable in order to obtain the same effect as described in the polyurethane resin (i), and the polyurethane resin (i) The polymer main chain end-capping method and the group represented by the general formula (A) as described above are preferable, and the preferable range is the same as that described for the polyurethane resin (i).

—Synthesis Method of Polyurethane Resin (ii) Obtained by Reacting Carboxyl Group-Containing Polyurethane with Compound Having Epoxy Group and Ethylenically Unsaturated Group in the Molecule—
As a method for synthesizing the polyurethane resin (ii), a diisocyanate compound and a diol compound are synthesized in an aprotic solvent by adding a known catalyst having an activity corresponding to each reactivity and heating. The molar ratio of the diisocyanate and diol compound to be used is preferably 1: 1.2 to 1.2: 1. When an isocyanate group remains at the end of the polymer, it is finally treated with an alcohol or an amine. Synthesized with no isocyanate groups remaining.

<< Content of acid-modified ethylenically unsaturated group-containing polyurethane resin >>
There is no restriction | limiting in particular in content of the acid-modified ethylenically unsaturated group containing polyurethane resin in solid content of the photosensitive resin composition of this invention, Although it can select suitably according to the objective, 5-80 mass% is Preferably, 10 to 75% by mass is more preferable, 10 to 70% by mass is further preferable, 10 to 60% by mass is further preferable, 10 to 50% by mass is further preferable, and 20 to 50% by mass is further preferable, It is particularly preferably 30 to 50% by mass.
If the content of the acid-modified ethylenically unsaturated group-containing polyurethane resin is too small, the folding resistance may not be kept good. If the content is too large, the developability may be impaired.

<Radically polymerizable compound>
There is no restriction | limiting in particular as a radically polymerizable compound used for this invention, Although it can select suitably according to the objective, The compound which has one or more functional groups which have an ethylenically unsaturated group is preferable.

Examples of the functional group having an ethylenically unsaturated group include a (meth) acryloyl group, a (meth) acrylamide group, a vinylphenyl group, a vinyl ester group, a vinyl ether group, an allyl ether group, and an allyl ester group.
There is no restriction | limiting in particular as a compound which has one or more functional groups which have the said ethylenically unsaturated group, Although it can select suitably according to the objective, At least 1 selected from the monomer which has a (meth) acryl group. Species are preferred.

There is no restriction | limiting in particular as a monomer which has the said (meth) acryloyl group, According to the objective, it can select suitably, For example, polyethyleneglycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meta) ) Monofunctional acrylates and monofunctional methacrylates such as acrylates; polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, dicyclopentane dimethylol di (meth) acrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate , Trimethylolpropane diacrylate, neopentyl glycol di (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol Tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, tri (acryloyloxyethyl) isocyanate Nurate, tri (acryloyloxyethyl) cyanurate, glycerin tri (meth) acrylate; a polyfunctional alcohol such as trimethylolpropane, glycerin, bisphenol and (meth) acrylate after addition reaction of ethylene oxide or propylene oxide; Examples thereof include polyfunctional acrylates and methacrylates such as epoxy acrylates which are reaction products of an epoxy resin and (meth) acrylic acid. Among these, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, dicyclopentane dimethylol di (meth) acrylate, Polyfunctional acrylates and methacrylates such as tricyclodecane dimethanol (meth) acrylate and epoxy acrylates which are reaction products of epoxy resin and (meth) acrylic acid are more preferable.
As radically polymerizable compounds, polyfunctional acrylates and methacrylates such as those having two or more acryloyloxy groups and methacryloyloxy groups, epoxy acrylates which are reaction products of epoxy resin and (meth) acrylic acid, and urethane in the main chain Polyfunctional urethane (meth) acrylate having a bond is particularly preferable.

  There is no restriction | limiting in particular as content in the said photosensitive resin composition solid content of the said radically polymerizable compound, Although it can select suitably according to the objective, 5 mass%-50 mass% are preferable, and 10 mass % To 40% by mass is more preferable. When the content is 5% by mass or more, developability and exposure sensitivity are good, and when the content is 50% by mass or less, the adhesiveness of the photosensitive layer can be prevented from becoming too strong.

<Thermal crosslinking agent>
The photosensitive resin composition of the present invention may contain a thermal crosslinking agent. There is no restriction | limiting in particular in the said thermal crosslinking agent, According to the objective, it can select suitably, In order to improve the film | membrane intensity | strength after hardening of the photosensitive layer formed using the said photosensitive resin composition, developability etc. In the range that does not adversely affect the above, for example, a compound containing an epoxy compound (for example, an epoxy compound having at least two oxirane groups in one molecule), or an oxetane compound having at least two oxetanyl groups in one molecule is used. An epoxy compound having an oxirane group, an epoxy compound having an alkyl group at the β-position, an oxetane compound having an oxetanyl group, a polyisocyanate compound, a polyisocyanate or a derivative thereof as described in JP-A-2007-47729 Compounds obtained by reacting a blocking agent with the isocyanate group of That.

  Moreover, a melamine derivative can be used as the thermal crosslinking agent. Examples of the melamine derivative include methylol melamine, alkylated methylol melamine (a compound obtained by etherifying a methylol group with methyl, ethyl, butyl, or the like). These may be used individually by 1 type and may use 2 or more types together. Among these, alkylated methylol melamine is preferable and hexamethylated methylol melamine is particularly preferable in that it has good storage stability and is effective in improving the surface hardness of the photosensitive layer or the film strength itself of the cured film.

  1 mass%-50 mass% are preferable, and, as for content in the said photosensitive resin composition solid content of the said thermal crosslinking agent, 3 mass%-30 mass% are more preferable. When the content is 1% by mass or more, the film strength of the cured film is improved, and when the content is 50% by mass or less, developability and exposure sensitivity are improved.

  Examples of the epoxy compound include an epoxy compound having at least two oxirane groups in one molecule and an epoxy compound having at least two epoxy groups having an alkyl group at the β-position in one molecule.

Examples of the epoxy compound having at least two oxirane groups per molecule include, for example, bisphenol F type epoxy resin (Epototo YDF-170, manufactured by Tohto Kasei Co., Ltd.), bixylenol type or biphenol type epoxy resin (“YX4000, Japan Epoxy resin "etc.) or a mixture thereof, a heterocyclic epoxy resin having an isocyanurate skeleton, etc. (" TEPIC, Nissan Chemical Industries, Ltd. "," Araldite PT810, Ciba Specialty Chemicals "), Bisphenol A type epoxy resin, novolac type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin Resin, halogenated epoxy resin (for example, low brominated epoxy resin, highly halogenated epoxy resin, brominated phenol novolac type epoxy resin, etc.), allyl group-containing bisphenol A type epoxy resin, trisphenolmethane type epoxy resin, diphenyldimethanol type Epoxy resin, phenol biphenylene type epoxy resin, dicyclopentadiene type epoxy resin (“HP-7200, HP-7200H; manufactured by Dainippon Ink & Chemicals, Inc.”), glycidylamine type epoxy resin (diaminodiphenylmethane type epoxy resin, dioxygen) Glycidylaniline, triglycidylaminophenol, etc.), glycidyl ester type epoxy resin (phthalic acid diglycidyl ester, adipic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester) , Dimer acid diglycidyl ester, etc.) hydantoin type epoxy resin, alicyclic epoxy resin (3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, bis (3,4-epoxycyclohexylmethyl) adipate, Dicyclopentadiene diepoxide, “GT-300, GT-400, ZEHPE3150; manufactured by Daicel Chemical Industries, Ltd.”), imide type alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, bisphenol A novolac type epoxy resin , Tetraphenylol ethane type epoxy resin, glycidyl phthalate resin, tetraglycidyl xylenoyl ethane resin, naphthalene group-containing epoxy resin (naphthol aralkyl type epoxy resin, naphthol novolak type epoxy resin) Tetrafunctional naphthalene type epoxy resin, commercially available products are “ESN-190, ESN-360; manufactured by Nippon Steel Chemical Co., Ltd.”, “HP-4032, EXA-4750, EXA-4700; manufactured by Dainippon Ink and Chemicals, Inc.” A reaction product of a polyphenol compound obtained by addition reaction of a phenol compound with a diolefin compound such as divinylbenzene or dicyclopentadiene and epichlorohydrin, or a ring-opening polymer of 4-vinylcyclohexene-1-oxide with peracetic acid. Epoxy resin having a linear phosphorus-containing structure, epoxy resin having a cyclic phosphorus-containing structure, α-methylstilbene liquid crystal epoxy resin, dibenzoyloxybenzene liquid crystal epoxy resin, azophenyl liquid crystal epoxy resin, Azomethine phenyl type liquid crystal epoxy tree Copolymers of fat, binaphthyl type liquid crystal epoxy resin, azine type epoxy resin, glycidyl methacrylate copolymer epoxy resin ("CP-50S, CP-50M; manufactured by NOF Corporation"), cyclohexylmaleimide and glycidyl methacrylate Examples thereof include epoxy resins, bis (glycidyloxyphenyl) fluorene type epoxy resins, and bis (glycidyloxyphenyl) adamantane type epoxy resins. These may be used alone or in combination of two or more.

In addition to the epoxy compound having at least two oxirane groups in one molecule, an epoxy compound containing at least two epoxy groups having an alkyl group at the β-position can be used, and the β-position is an alkyl group. Particularly preferred is a compound containing an epoxy group substituted with a (specifically, a β-alkyl-substituted glycidyl group or the like).
In the epoxy compound containing at least an epoxy group having an alkyl group at the β-position, all of two or more epoxy groups contained in one molecule may be a β-alkyl-substituted glycidyl group, and at least one epoxy group May be a β-alkyl-substituted glycidyl group.

Examples of the oxetane compound include oxetane compounds having at least two oxetanyl groups in one molecule.
Specifically, for example, bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, 1,4-bis [(3-methyl- 3-Oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) In addition to polyfunctional oxetanes such as methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate or oligomers or copolymers thereof, compounds having an oxetane group; Novolac resin, poly (p-hydroxystyrene), cardo type bisphenol , Calixarenes, calixresorcinarenes, and ether compounds such as silsesquioxane and other hydroxyl group-containing resins. In addition to these, an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate A polymer etc. are also mentioned.

  Further, as the polyisocyanate compound, a polyisocyanate compound described in JP-A No. 5-9407 can be used, and the polyisocyanate compound is aliphatic, cycloaliphatic or aromatic containing at least two isocyanate groups. It may be derived from a group-substituted aliphatic compound. Specifically, bifunctional isocyanate (for example, a mixture of 1,3-phenylene diisocyanate and 1,4-phenylene diisocyanate, 2,4- and 2,6-toluene diisocyanate, 1,3- and 1,4-xylylene). Diisocyanate, bis (4-isocyanate-phenyl) methane, bis (4-isocyanatocyclohexyl) methane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, etc.), the bifunctional isocyanate, trimethylolpropane, pentalithol tol Polyfunctional alcohols such as glycerin; alkylene oxide adducts of the polyfunctional alcohols and adducts of the bifunctional isocyanates; hexamethylene diisocyanate, hexamethylene-1,6-di Isocyanate or cyclic trimers thereof derivatives; and the like.

  As an isocyanate group blocking agent in a compound obtained by reacting a blocking agent with the polyisocyanate compound, that is, a compound obtained by reacting a blocking agent with an isocyanate group of polyisocyanate and derivatives thereof, alcohols (for example, isopropanol, tert-butanol etc.), lactams (eg ε-caprolactam etc.), phenols (eg phenol, cresol, p-tert-butylphenol, p-sec-butylphenol, p-sec-amylphenol, p-octylphenol, p -Nonylphenol, etc.), heterocyclic hydroxyl compounds (eg, 3-hydroxypyridine, 8-hydroxyquinoline, etc.), active methylene compounds (eg, dialkyl malonate, methyl ethyl ketoxime, Cetyl acetone, alkyl acetoacetate oxime, acetoxime, cyclohexanone oxime, etc.) and the like. In addition to these, compounds having at least one polymerizable double bond and at least one blocked isocyanate group in the molecule described in JP-A-6-295060 can be used.

  Examples of the melamine derivative include methylol melamine, alkylated methylol melamine (a compound obtained by etherifying a methylol group with methyl, ethyl, butyl, or the like). These may be used individually by 1 type and may use 2 or more types together. Among these, alkylated methylol melamine is preferable and hexamethylated methylol melamine is particularly preferable in that it has good storage stability and is effective in improving the surface hardness of the photosensitive layer or the film strength itself of the cured film.

<Photopolymerization initiator>
The photopolymerization initiator is not particularly limited as long as it has the ability to initiate the polymerization of the polymerizable compound, and can be appropriately selected according to the purpose. Those having photosensitivity are preferable, and may be an activator that generates an active radical by causing some action with a photoexcited sensitizer, and is an initiator that initiates cationic polymerization according to the type of monomer. May be.
The photopolymerization initiator preferably contains at least one component having a molecular extinction coefficient of at least about 50 within a wavelength range of about 300 nm to 800 nm. The wavelength is more preferably 330 nm to 500 nm.
As said photoinitiator, a neutral photoinitiator is preferable. Moreover, the other photoinitiator may be included as needed.

  The neutral photopolymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably a compound having at least an aromatic group, such as (bis) acylphosphine oxide or an ester thereof. More preferred are acetophenone compounds, benzophenone compounds, benzoin ether compounds, ketal derivative compounds, and thioxanthone compounds. Two or more neutral photopolymerization initiators may be used in combination.

  Examples of the photopolymerization initiator include (bis) acylphosphine oxide or esters thereof, acetophenone compounds, benzophenone compounds, benzoin ether compounds, ketal derivative compounds, thioxanthone compounds, oxime derivatives, organic peroxides, thiols, and the like. Compound etc. are mentioned. Among these, from the viewpoints of the sensitivity and storage stability of the photosensitive layer and the adhesion between the photosensitive layer and the printed wiring board forming substrate, oxime derivatives, (bis) acylphosphine oxide or esters thereof, acetophenone compounds, benzophenone Of these compounds, benzoin ether compounds, ketal derivative compounds, and thioxanthone compounds are preferred.

  Examples of the (bis) acylphosphine oxide, the acetophenone compound, the benzophenone compound, the benzoin ether compound, the ketal derivative compound, and the thioxanthone compound include, for example, paragraph [0042] of JP 2010-256399 A Examples thereof include (bis) acylphosphine oxides, acetophenone compounds, benzophenone compounds, benzoin ether compounds, ketal derivative compounds, and thioxanthone compounds.

  Examples of the oxime derivative include oxime derivatives described in paragraphs [0043] to [0059] of JP2010-256399A.

The said photoinitiator may be used individually by 1 type, and may use 2 or more types together.
There is no restriction | limiting in particular as content in the said photosensitive resin composition solid content of the said photoinitiator, Although it can select suitably according to the objective, 0.1 mass%-30 mass% are preferable, 0.5 mass%-20 mass% are more preferable, and 0.5 mass%-15 mass% are especially preferable.

<Flame Retardant>
The photosensitive resin composition of the present invention preferably contains one or more flame retardants.
Examples of flame retardants include phosphorus compounds, brominated compounds such as pentabromodiphenyl ether, octabromodiphenyl ether, decabromodiphenyl ether, tetrabromobisphenol A, hexabromocyclododecane, and chlorinated compounds such as chlorinated paraffin. However, a flame retardant comprising a phosphorus-containing compound (phosphorus-containing flame retardant) is preferable.

<< Phosphorus containing flame retardant >>
Examples of phosphorus-containing flame retardants include condensed phosphoric acid compounds, polyphosphoric acid melamine salts, phosphazene compounds, and organic phosphinic acid metal salts. These may be used alone or in combination of two or more.

  Examples of the condensed phosphoric acid compound include resorcinol bis-diphenyl phosphate, resorcinol bis-dixylenyl phosphate, bisphenol A bis-diphenyl phosphate, and commercially available products can be used. Examples of the commercially available products include CR-733S. , CR-741, CR-747, PX-200 (manufactured by Daihachi Chemical Co., Ltd.), FP-600, FP-700 (manufactured by Adeka), Reofos RDP, Reofos BAPP (manufactured by Ajinomoto Fine Techno Co., Ltd.) ), Etc.

  As a polyphosphate melamine salt, it is a compound represented, for example by the following general formula, and n shows one or more numbers. Commercial products can be used. As this commercial item, AP750, AP760, OP1312 (above, Clariant Japan company make), FP-2100J, FP-2200 (above, made by Adeka company), Hishiguard 6ME (Nihon Chemical Industry Co., Ltd. make), FCP-770 (Suzuhiro Chemical Co., Ltd.).

  Examples of the phosphazene compound include compounds represented by the following general formula. R is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and a commercially available product can be used. As this commercial item, SPS-100 (made by Otsuka Chemical Co., Ltd.) etc. are mentioned, for example.

Examples of the organic metal phosphinate, and for example those represented by the following general formula, ^{A P} and ^{B P} represents an alkyl group or an aryl group, M is, Mg, Ca, Al, Sb , Sn, Ge, It is at least one selected from Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Ni, and Na, and m represents an integer of 1 to 4. Here, M is preferably Al. Further, ^AP and ^BP are preferably an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group or an ethyl group. As the organic phosphinic acid metal salt, a commercially available product can be used, and examples of the commercially available product include OP-935 (manufactured by Clariant Japan).

In the present invention, an organic phosphinic acid metal salt is particularly preferable.
5 mass%-30 mass% are preferable, and, as for content in the said photosensitive resin composition solid content of the said flame retardant, 10 mass%-20 mass% are more preferable. If it is in the said preferable range, it is excellent in the resolution of a composition, and the flame retardance of a cured film, folding resistance, and insulation reliability can also be kept favorable.

<Thermosetting catalyst>
The photosensitive resin composition of the present invention may contain a thermosetting catalyst. As the thermosetting catalyst, for example, those described in paragraph [0093] of JP-A-2008-250074 can be used.

<Inorganic fine particles>
The photosensitive resin composition of the present invention may contain inorganic fine particles (inorganic filler). By containing inorganic fine particles, dripping at the time of coating can be prevented while keeping the tackiness of the composition good.
Examples of the inorganic fine particles include kaolin, barium sulfate, barium titanate, silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica. As a commercial item of the said barium sulfate, B-30 (made by Sakai Chemical Industry Co., Ltd.) etc. are mentioned, for example.
Among these, compounds having a silicon atom such as silica (compounds containing silicon as a constituent atom, such as silica and talc), barium sulfate and aluminum hydroxide are preferable, and barium sulfate and silica are particularly preferable.

  The average particle size of the inorganic fine particles is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5 μm or less, preferably 1 μm or less, more preferably 0.5 μm or less. If the average particle size is 5 μm or more, folding resistance may deteriorate.

  The content of the inorganic fine particles in the solid content of the photosensitive resin composition of the present invention is preferably 2 to 30% by mass, and more preferably 5 to 20% by mass.

<Other ingredients>
The other components are not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include fillers, thermal polymerization inhibitors, plasticizers, colorants (color pigments or dyes), and further groups. Adhesion promoters and other auxiliaries to the material surface (for example, conductive particles, fillers, antifoaming agents, leveling agents, peeling accelerators, antioxidants, fragrances, surface tension modifiers, chain transfer agents, etc.) May be used in combination.
By appropriately containing these components, it is possible to adjust properties such as the stability and film properties of the intended photosensitive resin composition.
Examples of the plasticizer include paragraphs [0103] to [0104] of JP-A-2008-250074.
Examples of the colorant include paragraphs [0105] to [0106] of JP-A-2008-250074.
Examples of the adhesion promoter include paragraphs [0107] to [0109] of JP-A-2008-250074.

  The photosensitive resin composition of the present invention usually contains an organic solvent. There is no restriction | limiting in particular in the said solvent, According to the objective, it can select suitably. Preferred examples of the organic solvent include ketone solvents such as acetone, methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone, alcohol ester solvents such as propylene glycol monomethyl ether acetate and diethylene glycol monoethyl ether acetate, aromatics such as toluene, xylene and solvent naphtha. System solvents and the like.

(Photosensitive laminate)
The photosensitive laminate of the present invention comprises at least a substrate and a photosensitive layer on the substrate, and further laminates other layers as necessary.
The photosensitive layer is a layer including a layer derived from the photosensitive resin composition of the present invention.
The photosensitive layer is obtained by, for example, directly applying the photosensitive resin composition of the present invention on the substrate using a spin coater, a slit spin coater, a roll coater, a die coater, a curtain coater, and the like, and then drying. Can be provided.
The drying conditions vary depending on each component, the type of solvent, the use ratio, and the like, but are usually about 60 seconds to 110 ° C. for about 30 seconds to about 60 minutes.

  There is no restriction | limiting in particular as thickness of the said photosensitive layer, Although it can select suitably according to the objective, 1 micrometer-100 micrometers are preferable, 2 micrometers-50 micrometers are more preferable, and 4 micrometers-30 micrometers are especially preferable.

<Base material>
The substrate is not particularly limited and can be appropriately selected according to the purpose. For example, the substrate can be arbitrarily selected from those having a high surface smoothness to those having an uneven surface. A substrate is preferred. Specific examples include known printed wiring board manufacturing substrates (printed substrates), glass plates (soda glass plates, etc.), synthetic resin films, paper, metal plates, and the like. A polyimide film on which metal wiring is formed is particularly preferable.

  The photosensitive laminate of the present invention can be widely used for forming a high-definition permanent pattern in the field of electronic materials, and can be suitably used for forming a permanent pattern of a printed circuit board, particularly a flexible wiring board.

(Permanent pattern forming method)
The permanent pattern forming method of the present invention includes at least an exposure step, and further includes other steps as necessary.

<Exposure process>
The exposure step is not particularly limited as long as it is a step of exposing the photosensitive layer formed by the photosensitive resin composition of the present invention, and can be appropriately selected according to the purpose. For example, the present invention The process etc. which expose with respect to the photosensitive layer in the said photosensitive laminated body are mentioned.

  There is no restriction | limiting in particular as said exposure, According to the objective, it can select suitably, For example, digital exposure, analog exposure, etc. are mentioned.

<Other processes>
There is no restriction | limiting in particular as said other process, According to the objective, it can select suitably, For example, the surface treatment process of a base material, a development process, a hardening process process, a post exposure process etc. are mentioned.

-Development process-
The developing step is a step of removing an unexposed portion of the photosensitive layer.
There is no restriction | limiting in particular as a removal method of the said exposed part, According to the objective, it can select suitably, For example, the method etc. which remove using a developing solution are mentioned.

  There is no restriction | limiting in particular as said developing solution, According to the objective, it can select suitably, For example, the developing solution as described in Paragraph [0171]-[0173] of Unexamined-Japanese-Patent No. 2008-250074 etc. are mentioned.

-Curing process-
The curing treatment step is a step of performing a curing treatment on the photosensitive layer in the formed pattern after the development step is performed.
There is no restriction | limiting in particular as said hardening process, Although it can select suitably according to the objective, For example, a whole surface exposure process, a whole surface heat processing, etc. are mentioned suitably.

  The method for the entire surface exposure treatment and the entire surface heat treatment is not particularly limited and may be appropriately selected depending on the purpose. For example, in paragraphs [0176] to [0177] of JP-A-2008-250074 The method of description is mentioned.

In the case where the permanent pattern forming method is a permanent pattern forming method for forming at least one of a protective film, an interlayer insulating film, and a solder resist pattern, on a printed circuit board, particularly on a flexible wiring board in the present invention. A permanent pattern can be formed by the permanent pattern forming method, and soldering can be performed as follows.
That is, by the development, a hardened layer that is the permanent pattern is formed, and the metal layer is exposed on the surface of the printed board. The metal layer exposed on the surface of the printed wiring board is subjected to Ni plating and gold plating, and then soldered. Then, a semiconductor or a component is mounted on the soldered portion. At this time, the permanent pattern by the hardened layer functions as a protective film, an insulating film (interlayer insulating film), a solder resist, particularly a flexible solder resist, and prevents external impact and conduction between adjacent electrodes. The

(Flexible circuit board)
The flexible circuit board of the present invention includes at least a base and a permanent pattern formed by the permanent pattern forming method, and further includes other members appropriately selected as necessary.
There is no restriction | limiting in particular as another member, According to the objective, it can select suitably, For example, the buildup board | substrate etc. in which the insulating layer was further provided between the base material and the said permanent pattern are mentioned.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated more concretely, this invention is not restrict | limited to these Examples at all. In the examples, “part” means “part by mass”.

(Analysis method)
The acid value, mass average molecular weight, and ethylenically unsaturated group content in the preparation examples were measured by the following methods.

<Acid value>
The acid value was measured according to JIS K0070. However, when the sample did not dissolve, dioxane or tetrahydrofuran was used as a solvent.

<Mass average molecular weight>
The mass average molecular weight was measured using a high-speed GPC apparatus (HLC-802A manufactured by Toyo Soda Co., Ltd.). That is, 0.5% by mass of THF (tetrahydrofuran) solution was used as a sample solution, two TSKgelGMH6 columns were used, 200 μL of sample was injected, eluted with the THF solution, and a refractive index detector at 25 ° C. It was measured. Next, the mass average molecular weight was determined from the molecular weight distribution curve calibrated with standard polystyrene.

<Ethylenically unsaturated group content>
The ethylenically unsaturated group content was determined by measuring the bromine number according to JIS K2605.

(Preparation example)
<Preparation of resin>
The following acid-modified ethylenically unsaturated group-containing polyurethane resins A to L were prepared by the method shown below. In addition, the numerical value in the parenthesis shown below each structural unit shows the molar ratio of each structural unit (mixing molar ratio of the monomer derived from each structural unit).

Preparation Example 1 Synthesis of acid-modified ethylenically unsaturated group-containing polyurethane resin A To a 1 L three-necked round bottom flask equipped with a condenser and a stirrer was 62.90 g of 2,2-bis (hydroxymethyl) butyric acid (DMBA). (0.469 mol), glycerol monomethacrylate (GLM) 82.00 g (0.512 mol), polypropylene glycol (molecular weight 1000) (PPG1000) 169.05 g (0.169 mol), 4,4-diphenylmethane diisocyanate (MDI) 14.39 g (0.058 mol), hexamethylene diisocyanate (HMDI) 183.75 g (1.093 mol), trimethylolethane (TME) 10.24 g, 4-hydroxy-2,2,6,6-tetra Methylpiperidine-N-oxyl free radical 1.54 g, Rohekisanon 522.34G, and as a catalyst, trade name: Neostann U-600 (Nitto Kasei Co., Ltd., an inorganic bismuth) was added 1.54 g, at 65 ° C., the mixture was heated and stirred 6 h. After cooling to room temperature, the concentration was adjusted with cyclohexanone to obtain an acid-modified ethylenically unsaturated group-containing polyurethane resin A solution having a solid content concentration of 50% by mass. The obtained acid-modified ethylenically unsaturated group-containing polyurethane resin A had a weight-average molecular weight of 22,000, a solid content acid value of 51 mgKOH / g, and an ethylenically unsaturated group content of 1.0 mmol / g.

Preparation Examples 2 to 12 Synthesis of acid-modified ethylenically unsaturated group-containing polyurethane resins B to L The raw materials to be used were adjusted except that the raw materials corresponding to the partial structures described above were changed to diol compounds, monool compounds, and diisocyanate compounds. In the same manner as in Example 1, acid-modified ethylenically unsaturated group-containing polyurethane resins B to L were prepared.

<Preparation of flame retardant dispersion>
3.64 parts by mass of metal phosphate (trade name: OP-935, manufactured by Clariant Japan), 19.97 parts by mass of each resin solution (solid content concentration 40% by mass), and 0.18 parts by mass of dispersant ( (Product name: BYK-W903, manufactured by Big Chemie Japan) and 3.26 parts by mass of cyclohexanone were weighed, and a motor mill M-50 (manufactured by Eiger) dispersed with zirconia beads having a diameter of 0.65 mm was used. To obtain a flame retardant dispersion.

<Preparation of pigment dispersion>
0.018 parts by mass of a blue pigment (manufactured by BASF, HELIOGEN BLUE D7086), 0.005 parts by mass of yellow pigment (manufactured by BASF, Pariotol Yellow D0960), and melamine (melamine, manufactured by Wako Pure Chemical Industries, Ltd.) 0 548 parts by mass and 69.29 parts by mass of cyclohexanone were weighed for 90 minutes using a motor mill M-50 (manufactured by Eiger) dispersing machine filled with zirconia beads having a diameter of 0.65 mm. Got.

Example 1
A photosensitive resin composition having the following composition was prepared.

-Composition of photosensitive resin composition solution-
・ Flame retardant dispersion ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 27.06 parts by mass ・ Pigment dispersion ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... 4.26 parts by mass-Acid-modified ethylenically unsaturated group-containing polyurethane resin A solution (adjusted to a solid content concentration of 40%) ... 6 .66 parts by mass-Irg-369 (manufactured by Ciba Specialty Chemicals) ... 0.50 parts by mass-Photopolymerization initiator (DETX-S, manufactured by Nippon Kayaku Co., Ltd.) ... 0.0047 parts by mass Photopolymerization initiator (EAB-F, Hodogaya Chemical Co., Ltd.) ... 0.0166 parts by mass-Radical polymerizable compound (Lipoxy VR-60, Showa Denko Co., Ltd.) ... 4.77 parts by mass-Surfactant (B1176 (3% diluted), manufactured by DIC)-... 1.94 parts by mass-Thermal crosslinking agent (Epo) Over preparative YDF-170, manufactured by Tohto Kasei Co., Ltd.) ...... 4.78 parts by mass Solvent (cyclohexanone) · · · · · · 2.80 parts by weight

(Examples 2 to 12)
The photosensitive resin composition was prepared in the same manner as in Example 1 except that the acid-modified ethylenically unsaturated group-containing polyurethane resin A solution was replaced with acid-modified ethylenically unsaturated group-containing polyurethane resins B to L in Example 1. Was prepared.

(Comparative Example 1)
In Example 1 above, instead of the acid-modified ethylenically unsaturated group-containing polyurethane resin A solution, a curable urethane resin (hereinafter referred to as “resin M”) described in Production Example 14 of JP 2010-150463 A is used. A photosensitive resin composition was obtained in the same manner as in Example 1 except that.

(Test example)
<Minimum development time>
The photosensitive resin composition of each of the above Examples and Comparative Examples was applied to the entire surface of the copper foil substrate by screen printing, dried in a hot air circulation drying oven at 80 ° C. for 30 minutes, allowed to cool to room temperature, and then 30 ° C. A 1% Na ₂ CO ₃ aqueous solution was developed at a spray pressure of 0.15 MPa for 10 seconds to 60 seconds at intervals of 5 seconds, and the presence or absence of residual development of the dried coating film was visually confirmed. The time when the coating film completely disappeared was defined as the shortest development time in each example and comparative example.

<Insulation>
The photosensitive resin compositions of the above examples and comparative examples were applied by screen printing on a rigid substrate on which a comb wiring of L / S 50 μm / 50 μm was formed instead of the copper foil substrate, and dried with hot air circulation It was dried at 80 ° C. for 30 minutes using an oven. After cooling this to room temperature, it was exposed under the condition of an exposure amount of 300 mJ / cm ² , and a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. was 1.5 times the shortest development time under a spray pressure of 0.15 MPa. Development was performed over time, and thermosetting was performed at 150 ° C. for 60 minutes using a hot-air circulating drying oven, and then cooled to room temperature to prepare a test plate.
Using the obtained test plate, the insulation was evaluated by the following method.

A bias voltage of DC 50 V was applied to the test plate produced as described above, and the test plate was subjected to 80 ° C. and 85% R.D. H. The resistance value after 1,000 hours and the presence or absence of a short circuit were confirmed in a constant temperature and humidity chamber. The judgment criteria are as follows. The results are shown in Table 1 below.
[Criteria]
A: Insulation resistance value after humidification 10 ⁸ Ω or more, no short circuit B: Insulation resistance value after humidification 10 ⁷ Ω or more, less than 10 ⁸ Ω, no short circuit C: Insulation resistance value after humidification, less than 10 ⁷ Ω, short circuit

<Folding resistance>
The photosensitive resin compositions of the above Examples and Comparative Examples were applied by screen printing on a copper foil substrate (Espanex) on which a wiring pattern of L / S 100 μm / 100 μm was created, and a hot air circulation type drying furnace was used. And dried at 80 ° C. for 30 minutes. After cooling this to room temperature, it was exposed under the condition of an exposure amount of 300 mJ / cm ² , and a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. was 1.5 times the shortest development time under a spray pressure of 0.15 MPa. Development was performed over time, and thermosetting was performed at 150 ° C. for 60 minutes using a hot-air circulating drying oven, and then cooled to room temperature to prepare a test plate.
Using the obtained test plate, folding resistance was evaluated by the following method.

The test plate was cut to a width of 0.5 cm and a length of 10 cm, the coating surface was bent outward at 180 ° C., a 200 g weight was placed on it, put back, and a 200 g weight was placed again for 3 seconds, and then cracks were observed. The presence or absence of was observed with an optical microscope. This operation was repeated, and folding resistance was evaluated according to the following evaluation criteria. The results are shown in Table 1 below.
〔Evaluation criteria〕
A: The number of times of bending until the occurrence of cracks is 10 times or more B: The number of times of bending until the occurrence of cracks is 7 to 9 times C: The number of times of bending until the occurrence of cracks is 6 times or less

As shown in Table 1, the cured film formed using the photosensitive resin composition (Examples 1 to 12) of the present invention containing the polyurethane resin defined in the present invention is either insulative or folding resistant. Also showed excellent properties.

Claims (13)

A photosensitive resin composition containing (A) an acid-modified ethylenically unsaturated group-containing polyurethane resin, (B) a radical polymerizable compound, (C) a thermal crosslinking agent, and (D) a photopolymerization initiator,
The (A) polyurethane resin has a structure represented by the following general formula (a1), a structure represented by the following general formula (a2), and a structure represented by the following general formula (a3). Photosensitive resin composition:
—O—L ^a1 (—R ^a1 ) _r —O— General formula (a1)
In the formula, L ^a1 represents a 2 + r-valent organic group. r shows the integer of 1-3. R ^a1 represents a group having an ethylenically unsaturated group;
Y ^a2 (-X ^a2- ) _b ... General formula (a2)
In the formula, X ^a2 represents * —NH—C (═O) O— or * —OC (═O) NH—, and “*” represents a bond on the side linked to Y ^a2 . Y ^a2 represents a b-valent linking group. b represents an integer of 3 or more;
-O-L ^a3 -O- General formula (a3)
In formula, ^La3 shows the bivalent coupling group which does not contain an ethylenically unsaturated group and a carboxyl group. ^{L a3} in formula (a3) ^{_{is, - (CH 2 CH 2 O}} ) n U1 CH 2 CH 2 -, - _[CH 2 CH _(CH 3) O] _{^{n U1 -CH 2 CH (CH 3}} ) -, - _{(CH 2 CH 2 CH 2 CH} 2 O) n U1 -CH 2 CH 2 CH 2 CH 2 -, the structure represented by the following general formula (LL1), the structure represented by the following general formula (LL2), the following general The photosensitive resin composition according to claim 1, wherein the photosensitive resin composition has a structure represented by the formula (LL3) or a structure represented by the following general formula (LL4):

Here, n ^{U1 to} n ^U4 , n and n ′ represent a number of 1 or more. R ^LL1 , R ^LL2 and R each represent a divalent chain hydrocarbon group or a divalent cyclic hydrocarbon group. The photosensitive resin composition according to claim 1 or 2, wherein the general formula (a1) is represented by the following general formula (a1-1) or the following general formula (a1-2):

In the formula, R ¹ , R ² and R ³ represent a hydrogen atom or a substituent. A represents a divalent organic group. X represents an oxygen atom, a sulfur atom or —N (R ¹² ) —, and R ¹² represents a hydrogen atom or a substituent.

In the formula, R ^a1-2 represents a hydrogen atom or methyl. L ^a1-2 represents a divalent organic group. The molecular weight of the L ^a3 is characterized in that it is a 400～8,000, photosensitive resin composition according to any one of claims 1 to 3. The photosensitive resin composition according to claim 4, wherein the molecular weight of L ^a3 in the general formula (a3) is 500 to 5,000.   (A) The polyurethane resin has a mass average molecular weight of 5,000 to 60,000, an acid value of solid content of 10 to 120 mgKOH / g, and an ethylenically unsaturated group content of 0.05 to 1. It is 2 mmol / g, The photosensitive resin composition of any one of Claims 1-5 characterized by the above-mentioned.   The photosensitive resin according to any one of claims 1 to 6, wherein (A) the polyurethane resin has 10 to 60 mass% of the structure represented by the general formula (a3) in the resin. Resin composition. (A) The polyurethane resin comprises at least one diisocyanate compound, at least one diol compound having an ethylenically unsaturated group and two hydroxyl groups, at least one diol compound having a carboxyl group and two hydroxyl groups, At least one diol compound having neither a saturated group nor a carboxyl group, and a trifunctional compound having three or more groups selected from a hydroxyl group and an isocyanate group, having neither an ethylenically unsaturated group nor a carboxyl group The photosensitive resin composition of any one of <1>-<7> which is resin obtained by making the above compound react.   The photosensitive resin composition according to claim 8, wherein the diisocyanate compound has a skeleton of 2,2-diphenylpropane type, diphenylmethane type, biphenyl type, naphthalene type, phenanthrene type, or anthracene type.   The photosensitive laminated body which has a photosensitive layer containing the photosensitive resin composition of any one of Claims 1-9 on a base material.   A flexible circuit board comprising a resist pattern obtained by photocuring a photosensitive layer containing the photosensitive resin composition according to any one of claims 1 to 9 on a base material.   The flexible circuit board according to claim 11, wherein the base material is a polyimide film.   A method for forming a permanent pattern, comprising exposing a photosensitive layer formed using the photosensitive resin composition according to claim 1.