Phosphorus-containing phenoxy resin, resin composition, cured product, laminate for electric / electronic circuits, and method for producing phosphorus-containing phenoxy resin

Abstract

Provided are a phosphorus-containing phenoxy resin having excellent fire-resistance and solubility, a resin composition containing said phosphorus-containing phenoxy resin and a curing agent, a cured product thereof having excellent heat resistance and strength, and a laminated plate for electric / electronic circuits.　This phosphorus-containing phenoxy resin is represented by formula (1), and has a weight average molecular weight of 10,000-200,000 and a percentage content of phosphorus of 1-6 mass%.　In the formula, X represents a divalent group represented by formula (2), and Y represents a hydrogen atom, an acyl group, or a glycidyl group. Z represents an acyl group or a hydrogen atom, and the acyl group accounts for 5 mol% or more of all of said Z. "A" represents a benzene ring, a naphthalene ring, an anthracene ring, or a phenanthrene ring. W represents a phosphorus-containing group represented by formula (3).

Description

[Technical Field]

[0001] The present invention relates to a phosphorus-containing phenoxy resin having excellent flame retardancy and solvent solubility, a resin composition containing the phosphorus-containing phenoxy resin and a curing agent, a cured product thereof having excellent flame retardancy and strength, and a laminate for electric and electronic circuits made of the resin composition. [Background technology]

[0002] Epoxy resins are widely used in fields such as paints, civil engineering, adhesives, and electrical materials due to their excellent heat resistance, adhesive properties, chemical resistance, water resistance, mechanical strength, and electrical properties. Furthermore, film-forming properties can be imparted by increasing the molecular weight using various methods. Such high-molecular-weight epoxy resins are called phenoxy resins. In particular, bisphenol A-type phenoxy resins are primarily used as base resins for paint varnishes and film molding, and are added to epoxy resin varnishes to adjust flowability and improve toughness and adhesive properties when cured. Furthermore, those containing phosphorus or bromine atoms in the skeleton are used as flame retardants incorporated into epoxy resin compositions and thermoplastic resins.

[0003] Phenoxy resins used in electrical materials such as laminates for electrical and electronic circuits require flame retardancy and solvent solubility.

[0004] Therefore, halogen-free flame-retardant technologies using phosphorus compounds have been investigated to impart flame retardancy to epoxy resins. Patent Documents 1 to 3 disclose phosphorus-containing flame-retardant epoxy resins obtained by reacting specific phosphorus compounds with epoxy resins. Patent Documents 1 and 2 disclose phosphorus-containing flame-retardant epoxy resins obtained by reacting 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide with an epoxy resin in a predetermined molar ratio. Patent Document 3 also discloses a phosphorus-containing flame-retardant epoxy resin obtained by reacting 10-(2,7-dihydroxynaphthyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide with an epoxy resin in a predetermined ratio. However, the phosphorus-containing flame-retardant epoxy resins obtained by these methods have poor solubility in epoxy resins and solvents. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 04-11662 [Patent Document 2] Japanese Patent Application Laid-Open No. 2000-309623 [Patent Document 3] Japanese Patent Application Publication No. 11-279258 Summary of the Invention

[0006] The present invention aims to provide a phosphorus-containing phenoxy resin having excellent flame retardancy and solubility, and to provide a cured product having excellent flame retardancy and strength by curing a resin composition containing the same.

[0007] In order to solve the above problems, the present inventors have conducted extensive research into phosphorus-containing phenoxy resins and have found that phosphorus-containing phenoxy resins having a specific structure have excellent flame retardancy and solubility, and have also found that a cured product obtained by curing a resin composition containing such a phosphorus-containing phenoxy resin has excellent flame retardancy and strength, thereby completing the present invention.

[0008] That is, the present invention relates to a phosphorus-containing phenoxy resin represented by the following formula (1), having a weight average molecular weight of 10,000 to 200,000 and a phosphorus content of 1 to 6 mass %. [ka] In the formula, X is independently a divalent group containing a dioxy group represented by the following formula (2), and each Y is independently a hydrogen atom, an acyl group having a hydrocarbon group of 1 to 20 carbon atoms, or a glycidyl group. Z is an acyl group having a hydrocarbon group of 1 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of the acyl group is the above. n is the average number of repetitions and is 15 to 500.

[0009] [ka] In the formula, A is a trivalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and W is a phosphorus-containing group represented by formula (3). 1 and R 2 are each independently a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom, and may be linear, branched, or cyclic. 1 and R 2 may be bonded to form a cyclic structure, and k1 and k2 are each independently 0 or 1.

[0010] The epoxy equivalent of the phosphorus-containing phenoxy resin is preferably 2000 to 50000 g / eq.

[0011] The present invention also provides a resin composition containing the above phosphorus-containing phenoxy resin and a curing agent. The resin composition contains 0.1 to 100 parts by mass of a curing agent as a solid content relative to 100 parts by mass of a solid content of the phosphorus-containing phenoxy resin. Part included It is best to do so.

[0012] The resin composition contains the phosphorus-containing phenoxy resin, an epoxy resin, and a curing agent, and the mass ratio of the solid content of the phosphorus-containing phenoxy resin to the epoxy resin can be 99 / 1 to 1 / 99. This resin composition contains 0.1 to 100 parts by mass of a curing agent as a solid content per 100 parts by mass of the total solid content of the phosphorus-containing phenoxy resin and the epoxy resin. Part included It is best to do so.

[0013] The curing agent to be blended in the resin composition is at least one selected from the group consisting of acrylic ester resins, melamine resins, urea resins, phenolic resins, acid anhydride compounds, amine compounds, imidazole compounds, amide compounds, cationic polymerization initiators, organic phosphines, polyisocyanate compounds, blocked isocyanate compounds, and active ester curing agents.

[0014] The present invention also relates to a cured product obtained by curing the above-mentioned resin composition. Furthermore, the present invention relates to a laminate for electric / electronic circuits, which is made using the above resin composition.

[0015] The present invention also provides a method for producing the above phosphorus-containing phenoxy resin, which comprises reacting a bifunctional epoxy resin represented by the following formula (4) with a compound represented by the following formula (5). [ka] During the ceremony, G is a glycidyl group, X 1 are independently divalent groups containing a dioxy group represented by the above formula (2), and X in formula (4) and formula (5) 1 Among them, the dioxy group represented by formula (2) is included as a whole. Z 1 is an acyl group having a hydrocarbon group of 1 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of the acyl group is the above. 1 The compound may be a mixture of two or more compounds selected from compounds in which both of the above groups are acyl groups, compounds in which one of the above groups is an acyl group, and compounds in which both of the above groups are hydrogen atoms. m is the average number of repetitions and is between 0 and 6.

[0016] Furthermore, the present invention provides a method for producing the phosphorus-containing phenoxy resin, characterized by reacting 0.05 moles or more and 2.0 moles or less of an acylating agent with 1 mole of an alcoholic hydroxyl group equivalent of phosphorus-containing phenoxy resin (a) represented by the following formula (6): [ka] In the formula, X 2 are independently divalent groups containing a dioxy group represented by the above formula (2), and Y 2 are each independently a hydrogen atom or a glycidyl group, and n is the average number of repetitions and is 15 to 500.

[0017] According to the present invention, a phosphorus-containing phenoxy resin having excellent flame retardancy and solubility can be provided. Furthermore, a resin composition using this phosphorus-containing phenoxy resin can provide a cured product having excellent flame retardancy and strength. DETAILED DESCRIPTION OF THE INVENTION

[0018] The phosphorus-containing phenoxy resin of the present invention has a weight average molecular weight (Mw) represented by the above formula (1) of 10,000 to 200,000, a phosphorus content of 1 to 6 mass%, and has phosphorus-containing dioxy groups represented by the above formula (2), and further has a structure in which some or all of the hydrogen atoms in the hydroxyl groups have been substituted with acyl groups (Z). Here, if the Mw is less than 10,000, film-forming properties and mechanical properties (particularly folding endurance) may be reduced, which is undesirable. If the Mw is more than 200,000, compatibility may be reduced, making the resin difficult to handle, which is undesirable. The Mw is preferably 15,000 to 160,000, more preferably 20,000 to 120,000, and even more preferably 20,000 to 120,000. The Mw of the phosphorus-containing phenoxy resin can be measured by gel permeation chromatography (GPC) as described in the examples.

[0019] The phosphorus-containing phenoxy resin of the present invention has a structure in which the hydrogen atoms in the hydroxyl groups are substituted with acyl groups, which results in low polarity, low moisture absorption, and good solubility. In addition, it also has the effect of providing excellent dielectric properties.

[0020] The phenoxy resin of the present invention can be advantageously obtained by the manufacturing method of the present invention. In this specification, the phosphorus-containing phenoxy resin obtained by the manufacturing method of the present invention is sometimes referred to as the "phosphorus-containing phenoxy resin of the present invention," the cured product obtained by curing the resin composition of the present invention is sometimes referred to as the "cured product of the present invention," and the manufacturing method of the phosphorus-containing phenoxy resin of the present invention is sometimes referred to as the "manufacturing method of the present invention."

[0021] In the above formula (1), X is independently a divalent group containing a dioxy group represented by the above formula (2), that is, a dioxy group represented by formula (2) or a group consisting of this dioxy group and another divalent group other than this. The group represented by formula (2) is called a dioxy group because it has oxygen atoms at both ends. The divalent group is either the dioxy group represented by formula (2) or another divalent group other than this, but includes the dioxy group represented by formula (2). Examples of divalent groups other than the dioxy group include a divalent group represented by -O-Ar-O-, where Ar includes a residue in which two hydroxyl groups have been removed from a bifunctional phenol compound that may be used in combination as described below. The number of moles of dioxy groups represented by formula (2) in the total number of X's is determined depending on the structure of the phosphorus-containing group represented by W and the desired phosphorus content.

[0022] The dioxy group represented by the formula (2) is a residue obtained by removing two hydroxyl groups from a phosphorus-containing bifunctional phenol compound (p1) described below. This phosphorus-containing bifunctional phenol compound (p1) is obtained by reacting an organic phosphorus compound (p2) with a quinone compound.

[0023] In formula (2), A is a trivalent aromatic hydrocarbon group having 6 to 20 carbon atoms and derived from a quinone compound. Examples of the aromatic hydrocarbon group include aromatic ring groups selected from a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthrene ring, and preferably a benzene ring group or a naphthalene ring group. These aromatic ring groups may have, as a substituent, any of an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, and an aralkyloxy group having 7 to 12 carbon atoms.

[0024] Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a t-butyl group, and a hexyl group. Examples of the alkoxy group include an alkoxy group derived from these alkyl groups. Examples of the cycloalkyl group having 5 to 8 carbon atoms include a cyclohexyl group. Examples of the aryl group or aryloxy group having 6 to 10 carbon atoms include a phenyl group, a naphthyl group, a phenoxy group, and a naphthyloxy group. Examples of the aralkyl group or aralkyloxy group having 7 to 11 carbon atoms include a benzyl group, a phenethyl group, a 1-phenylethyl group, a benzyloxy group, and a naphthylmethyloxy group. Preferred examples of A include a benzene ring, a methyl-substituted benzene ring, a 1-phenylethyl-substituted benzene ring, a naphthalene ring, a methyl-substituted naphthalene ring, or a 1-phenylethyl-substituted naphthalene ring. For applications requiring better solubility, a benzene ring, a methyl-substituted benzene ring, or a 1-phenylethyl-substituted benzene ring is preferred, and for applications requiring better flame retardancy or heat resistance, a naphthalene ring, a methyl-substituted naphthalene ring, or a 1-phenylethyl-substituted naphthalene ring is preferred.

[0025] In formula (2), W is a residue of an organic phosphorus compound (p2) described later. 1 and R 2are hydrocarbon groups having 1 to 20 carbon atoms which may have a heteroatom, and may be different or the same, and may be linear, branched, or cyclic. 1 and R 2 may be bonded to form a ring structure. Examples of heteroatoms include oxygen atoms, which can be contained between carbon atoms constituting the hydrocarbon chain or hydrocarbon ring or at the end. Examples of hydrocarbon groups having 1 to 20 carbon atoms include alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 5 to 12 carbon atoms, alkoxy groups having 1 to 8 carbon atoms, cycloalkoxy groups having 5 to 8 carbon atoms, aryl groups having 6 to 12 carbon atoms, aralkyl groups having 7 to 12 carbon atoms, alkynyl groups having 2 to 12 carbon atoms, aryloxy groups having 6 to 10 carbon atoms, and aralkyloxy groups having 7 to 11 carbon atoms, and aromatic ring groups such as a benzene ring are particularly preferred.

[0026] Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a t-pentyl group, an n-hexyl group, an isohexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, and an n-dodecyl group. Examples of the cycloalkyl group having 5 to 12 carbon atoms include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a methylcyclohexyl group, a cyclooctyl group, a trimethylcyclohexyl group, a cyclodecyl group, and a cyclododecyl group.

[0027] Examples of the alkoxy group having 1 to 8 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentoxy group, an isopentoxy group, a neopentoxy group, a t-pentoxy group, an n-hexyloxy group, an isohexyloxy group, an n-heptoxy group, an n-octyloxy group, an n-nonyloxy group, an n-decyloxy group, an n-undecyloxy group, and an n-dodecyloxy group. Examples of the cycloalkoxy group having 5 to 8 carbon atoms include a cyclopentoxy group, a cyclohexyloxy group, a cycloheptoxy group, a methylcyclohexyloxy group, a cyclooctyloxy group, a trimethylcyclohexyloxy group, a cyclodecyloxy group, and a cyclododecyloxy group.

[0028] Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, an ethylphenyl group, a styryl group, a xylyl group, an n-propylphenyl group, an isopropylphenyl group, a mesityl group, an ethynylphenyl group, a naphthyl group, and a vinylnaphthyl group.

[0029] Examples of the aralkyl group having 7 to 12 carbon atoms include a benzyl group, a methylbenzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a naphthylmethyl group, a phenethyl group, a 1-phenylethyl group, and a 2-phenylisopropyl group.

[0030] Examples of the alkynyl group having 2 to 12 carbon atoms include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynyl group, a 2-butynyl group, a 3-butynyl group, a 1,3-butadiynyl group, a phenylethynyl group, and a naphthylethynyl group.

[0031] Examples of the aryloxy group having 6 to 10 carbon atoms include a phenoxy group, an o-tolyloxy group, an m-tolyloxy group, a p-tolyloxy group, an ethylphenoxy group, a xylyloxy group, an n-propylphenoxy group, an isopropylphenoxy group, a mesityloxy group, an ethynylphenoxy group, and a naphthyloxy group.

[0032] Examples of the aralkyloxy group having 7 to 11 carbon atoms include a benzyloxy group, a methylbenzyloxy group, a dimethylbenzyloxy group, a trimethylbenzyloxy group, a naphthylmethoxy group, a phenethyloxy group, and a 2-phenylisopropoxy group.

[0033] Also, R 1 and R 2When is an aromatic ring group, it may have, as a substituent, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms.

[0034] W is preferably a phosphorus-containing group represented by the following formula (3a) or (3b). [ka] In the formula, R 3 and R 4 are each independently a hydrocarbon group having 1 to 11 carbon atoms, specifically a methyl group, an ethyl group, a t-butyl group, a cyclohexyl group, a phenyl group, a tolyl group, a benzyl group, etc., and preferably a methyl group, a cyclohexyl group, a phenyl group, a tolyl group, or a benzyl group, and more preferably a methyl group, a phenyl group, or a benzyl group. However, when four R 3 The total number of carbon atoms in each benzene ring is 14 or less, and the five R 4 The total number of carbon atoms is 14 or less.

[0035] Preferred examples of W other than those of the above formula (3a) and formula (3b) include phosphorus-containing groups represented by the following formulae (a1) to (a10). [ka]

[0036] In formula (1), each Y is independently a hydrogen atom, an acyl group having a hydrocarbon group of 1 to 20 carbon atoms, or a glycidyl group. When Y is a hydrogen atom, a hydroxyl group is provided at the terminal, when Y is an acyl group, an ester group is provided at the terminal, and when Y is a glycidyl group, an epoxy group is provided at the terminal; therefore, it is advisable to control the ratio depending on the application. The hydrocarbon group having 1 to 20 carbon atoms is preferably an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 13 carbon atoms, specific examples of which include the groups exemplified above. Among these, an acyl group having a hydrocarbon group having 1 to 7 carbon atoms is more preferred, with an acetyl group, a propanoyl group, a butanoyl group, a benzoyl group, and a methylbenzoyl group being even more preferred, and an acetyl group and a benzoyl group being particularly preferred. An acetyl group is understood to be an acyl group having a hydrocarbon group with 1 carbon atom.

[0037] In formula (1), Z is an acyl group having a hydrocarbon group of 1 to 20 carbon atoms or a hydrogen atom. At least 5 mol% of Z are acyl groups, and the remainder are hydrogen atoms. Preferably, at least 10 mol%, more preferably at least 50 mol%, and even more preferably at least 70 mol% of Z are the above-mentioned acyl groups. The upper limit is preferably 100 mol%, but substantially 95 mol% is sufficient. Specific examples of acyl groups having a hydrocarbon group of 1 to 20 carbon atoms are the same as those exemplified above for Y, and preferred acyl groups are also the same.

[0038] When all Z's (100 mol%) are acyl groups, the phosphorus-containing phenoxy resin of the present invention does not contain secondary hydroxyl groups, and the dielectric properties and moisture resistance can be further improved. On the other hand, when fine-tuning the adhesion to metals, for example, by leaving some of the Z's as hydrogen atoms, it is possible to intentionally allow an appropriate amount of secondary hydroxyl groups to be present in the phosphorus-containing phenoxy resin of the present invention, as long as this does not significantly affect other physical properties such as moisture resistance.

[0039] In formula (1), n ​​is the number of repeating units and is an average value. The value ranges from 15 to 500. From the viewpoints of moldability and handleability, it is preferably from 17 to 400, and more preferably from 20 to 300. The number n can be calculated from the number average molecular weight (Mn) obtained by GPC.

[0040] The phosphorus content of the phosphorus-containing phenoxy resin of the present invention is 1 to 6 mass%, preferably 2 to 5.5 mass%, and more preferably 3 to 5 mass%. If the phosphorus content is less than 1 mass%, the flame retardancy may be insufficient. If the phosphorus content is more than 6 mass%, the solvent solubility may be significantly reduced.

[0041] The epoxy equivalent of the phosphorus-containing phenoxy resin of the present invention is not particularly limited, but is preferably in the range of 2,000 to 50,000 g / eq. Within this range, the phosphorus-containing phenoxy resin of the present invention itself can participate in the curing reaction and be incorporated into a crosslinked structure.

[0042] The phosphorus-containing phenoxy resin of the present invention is one in which some or all of the secondary hydroxyl groups are acylated, and can be obtained by various methods. Preferred production methods include, for example, the following production method. (A): A production method in which a bifunctional epoxy resin represented by the above formula (4) is reacted with a diester compound and / or a bifunctional phenol compound represented by the above formula (5). Hereinafter, this method may be referred to as production method (A). (B): A production method in which a phosphorus-containing phenoxy resin represented by the above formula (6) (sometimes referred to as phosphorus-containing phenoxy resin (a) to distinguish it from the phosphorus-containing phenoxy resin of the present invention) is reacted with an acid component (acylating agent) such as an acid anhydride of an organic acid, an organic acid halide, or an organic acid ester. Hereinafter, this method may be referred to as production method (B). The phosphorus-containing phenoxy resins obtained by the production methods (A) and (B) are the phosphorus-containing phenoxy resins of the present invention, and are represented by the same formula (1).

[0043] The production method (A) is a method in which a bifunctional epoxy resin represented by formula (4) is reacted with a compound represented by formula (5). In the above formula (4), G is S It is a dialkyl group, and m is the number of repetitions, the average value of which is 0 or more and 6 or less. In equation (5), Z 1At least 5 mol % of the above are acyl groups having a hydrocarbon group having 1 to 20 carbon atoms, and the remainder are hydrogen atoms. 1 and Z may be a mixture of two or more compounds selected from compounds in which both of Z are acyl groups, compounds in which one is an acyl group and the other is a hydrogen atom, and compounds in which both are hydrogen atoms. 1 When both are acyl groups, it becomes a diester, and when both are hydrogen atoms, it becomes a diphenol. The compound represented by formula (5) is called a diester compound. Diester compounds are classified into 1 It is preferable that both of the above are acyl groups or that the main component (50% or more) of the compound (mixture) is such a compound.

[0044] X in formula (4) and formula (5) 1 is selected to give X in equation (1). Therefore, X in equations (4) and (5) 1 contains a dioxy group represented by formula (2). For example, X in either formula (4) or formula (5) 1 When one of the groups contains this dioxy group, the other may or may not contain this dioxy group.

[0045] The phosphorus-containing phenoxy resin of the present invention necessarily contains a dioxy group represented by formula (2). As long as this requirement is met, the dioxy group represented by formula (2) may be contained in any of the starting bifunctional epoxy resin, diester compound, and bifunctional phenol compound, and the proportion thereof is not limited. In addition, X in the above formula (4) or formula (5) 1 When the dioxy group represented by formula (2) is not included, X 1 Another divalent group can be introduced into

[0046] The bifunctional epoxy resin used in the production method (A) of the present invention is an epoxy resin represented by the above formula (4), and examples thereof include an epoxy resin obtained by reacting a bifunctional phenol compound represented by the following formula (8) with epihalohydrin in the presence of an alkali metal compound.

[0047] Examples of epihalohydrins include epichlorohydrin and epibromohydrin. Examples of alkali metal compounds include alkali metal hydroxides such as sodium hydroxide, lithium hydroxide, and potassium hydroxide; alkali metal salts such as sodium carbonate, sodium bicarbonate, sodium chloride, lithium chloride, and potassium chloride; alkali metal alkoxides such as sodium methoxide and sodium ethoxide; alkali metal salts of organic acids such as sodium acetate and sodium stearate; alkali metal phenoxides, sodium hydride, and lithium hydride.

[0048] In the reaction of a bifunctional phenol compound with epihalohydrin to obtain the starting epoxy resin, an alkali metal compound is used in an amount of 0.80 to 1.20 times by mole, preferably 0.85 to 1.05 times by mole, relative to the functional groups in the bifunctional phenol compound. Less than this amount is undesirable because the amount of residual hydrolyzable chlorine increases. The alkali metal compound is used in the form of an aqueous solution, an alcohol solution, or a solid.

[0049] In the epoxidation reaction, an excess amount of epihalohydrin is used relative to the bifunctional phenol compound. Typically, 1.5 to 15 moles of epihalohydrin are used per mole of functional groups in the bifunctional phenol compound, preferably 2 to 10 moles, and more preferably 5 to 8 moles. If the amount is greater than this, production efficiency decreases, and if it is less than this, the amount of high molecular weight epoxy resin produced increases, making it unsuitable as a raw material for phosphorus-containing phenoxy resin.

[0050] The epoxidation reaction is usually carried out at a temperature of 120°C or lower. If the reaction temperature is high, the amount of so-called difficultly hydrolyzable chlorine increases, making it difficult to achieve high purity. The temperature is preferably 100°C or lower, and more preferably 85°C or lower.

[0051] [ka] In the formula, X 1 is X in the above formula (4) or (5). 1 is the same as:

[0052] When a bifunctional phenol compound represented by the above formula (8) is reacted with epihalohydrin, m usually becomes greater than 0. In order to make m 0, an epoxy resin produced by a known method can be highly purified by distillation, crystallization, or the like, or a bifunctional phenol compound represented by the above formula (8) can be allylated and then epoxidized by oxidizing the olefin moiety.

[0053] The diester compound used in the production method (A) of the present invention can be obtained, for example, by acylation of a bifunctional phenol compound represented by the above formula (8) through a condensation reaction with an acid anhydride of an organic acid, a halide of an organic acid, or an organic acid.

[0054] By using an epoxy resin in which m in formula (4) is 0 as the raw material, the phosphorus-containing phenoxy resin of the present invention does not contain secondary hydroxyl groups, thereby further improving the dielectric properties and moisture resistance. Furthermore, when finely adjusting the adhesion to metal, for example, by using an epoxy resin with an appropriate m number, it is possible to intentionally allow an appropriate amount of secondary hydroxyl groups to be present in the phosphorus-containing phenoxy resin of the present invention, within a range that does not significantly affect other physical properties such as moisture resistance.

[0055] The bifunctional epoxy resin or diester compound used in the production method (A) of the present invention contains a dioxy group represented by the above formula (2). The total phosphorus content of the starting bifunctional epoxy resin and diester compound, and the bifunctional phenol compound used in combination as needed, determines the phosphorus content of the phosphorus-containing phenoxy resin of the present invention, so the types and amounts of the bifunctional epoxy resin, diester compound, and bifunctional phenol compound used can be adjusted depending on the desired phosphorus content.

[0056] The amount of the bifunctional epoxy resin and diester compound used is preferably 0.8 to 1.0 equivalents of ester group and / or hydroxyl group per equivalent of epoxy group. This equivalent ratio is preferred because it facilitates the promotion of high molecular weight polymerization with epoxy groups at the molecular terminals. It is also possible to replace a portion of the diester compound with a bifunctional phenol compound represented by the above formula (8). As described above, this allows the phosphorus-containing phenoxy resin of the present invention to have an appropriate amount of secondary hydroxyl groups, allowing for fine adjustment of its physical properties. In the production method (A), a polymerization reaction and an ester exchange reaction occur, resulting in an increase in Mw and the production of a phenoxy resin, while some of the hydroxyl groups of the phenoxy resin are esterified.

[0057] In the production method (A), a catalyst may be used. The catalyst may be any compound having catalytic activity that promotes the reaction between the epoxy group and the ester group. Examples of the catalyst include tertiary amines, cyclic amines, imidazoles, organic phosphorus compounds, and quaternary ammonium salts. These catalysts may be used alone or in combination of two or more.

[0058] Examples of tertiary amines include, but are not limited to, triethylamine, tri-n-propylamine, tri-n-butylamine, triethanolamine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and the like.

[0059] Examples of cyclic amines include, but are not limited to, 1,4-diazabicyclo[2,2,2]octane (DABCO), 1,8-diazabicyclo[5,4,0]undecene-7 (DBU), 1,5-diazabicyclo[4,3,0]nonene-5 (DBN), N-methylmorpholine, pyridine, and N,N-dimethylaminopyridine (DMAP).

[0060] Examples of imidazoles include, but are not limited to, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, and 1-benzyl-2-phenylimidazole.

[0061] Examples of the organic phosphorus compounds include phosphines such as tri-n-propylphosphine, tri-n-butylphosphine, diphenylmethylphosphine, triphenylphosphine, tris(p-tolyl)phosphine, tricyclohexylphosphine, tri(t-butyl)phosphine, tris(p-methoxyphenyl)phosphine, paramethylphosphine, 1,2-bis(dimethylphosphino)ethane, and 1,4-bis(diphenylphosphino)butane; tetramethylphosphonium bromide, tetramethylphosphonium iodide, tetramethylphosphonium hydroxide, tetrabutylphosphonium hydroxide, and tetramethylphosphonium iodide; Examples of the phosphonium salts include, but are not limited to, trimethylcyclohexylphosphonium chloride, trimethylcyclohexylphosphonium bromide, trimethylbenzylphosphonium chloride, trimethylbenzylphosphonium bromide, tetraphenylphosphonium bromide, triphenylmethylphosphonium bromide, triphenylmethylphosphonium iodide, triphenylethylphosphonium chloride, triphenylethylphosphonium bromide, triphenylethylphosphonium iodide, triphenylbenzylphosphonium chloride, and triphenylbenzylphosphonium bromide.

[0062] Examples of quaternary ammonium salts include, but are not limited to, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium hydroxide, triethylmethylammonium chloride, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, tetrapropylammonium bromide, tetrapropylammonium hydroxide, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium hydroxide, benzyltributylammonium chloride, and phenyltrimethylammonium chloride.

[0063] Among the catalysts listed above, 4-(dimethylamino)pyridine, 1,4-diazabicyclo[2,2,2]octane, 1,8-diazabicyclo[5,4,0]undecene-7, 1,5-diazabicyclo[4,3,0]nonene-5, 2-ethyl-4-methylimidazole, tris(p-tolyl)phosphine, tricyclohexylphosphine, tri(t-butyl)phosphine, and tris(p-methoxyphenyl)phosphine are preferred, and 4-(dimethylamino)pyridine, 1,8-diazabicyclo[5,4,0]undecene-7, 1,5-diazabicyclo[4,3,0]nonene-5, and 2-ethyl-4-methylimidazole are particularly preferred.

[0064] The amount of catalyst used is usually 0.001 to 1 mass% of the reaction solids, but when these compounds are used as catalysts, the catalyst remains as a residue in the resulting phosphorus-containing phenoxy resin, which may deteriorate the insulating properties of the printed wiring board or shorten the pot life of the composition, so the content of catalyst-derived nitrogen in the phosphorus-containing phenoxy resin is preferably 0.5 mass% or less, more preferably 0.3 mass% or less. Also, the content of catalyst-derived phosphorus in the phosphorus-containing phenoxy resin is preferably 0.5 mass% or less, more preferably 0.3 mass% or less.

[0065] In the production method (A) of the present invention, a reaction solvent may be used, and the solvent may be any solvent that dissolves the phosphorus-containing phenoxy resin. Examples include aromatic solvents, ketone solvents, amide solvents, glycol ether solvents, and ester solvents. These solvents may be used alone or in combination of two or more.

[0066] Examples of aromatic solvents include benzene, toluene, and xylene.

[0067] Examples of ketone solvents include acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, 2-heptanone, 4-heptanone, 2-octanone, cyclohexanone, acetylacetone, dioxane, diisobutyl ketone, isophorone, methylcyclohexanone, and acetophenone.

[0068] Examples of amide solvents include formamide, N-methylformamide, N,N-dimethylformamide (DMF), acetamide, N-methylacetamide, N,N-dimethylacetamide, 2-pyrrolidone, and N-methylpyrrolidone.

[0069] Examples of glycol ether solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-butyl ether, and other ethylene glycol monoalkyl ethers; ethylene glycol dialkyl ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, and propylene glycol monomethyl ether; propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol mono-n-butyl ether; ethylene glycol dialkyl ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and ethylene glycol dibutyl ether; diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, and triethylene glycol dibutyl ether; propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, and propylene glycol dibutyl ether; polypropylene glycol dialkyl ethers such as dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol dibutyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, and tripropylene glycol dibutyl ether; ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol monobutyl ether acetate; diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triethylene glycol monomethyl ether acetate, and triethylene glycol monoethyl ether acetate;Examples include polyethylene glycol monoalkyl ether acetates such as triethylene glycol monobutyl ether acetate, and propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol monobutyl ether acetate.

[0070] Examples of ester solvents include methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, benzyl acetate, ethyl propionate, ethyl butyrate, butyl butyrate, valerolactone, and butyrolactone. etc.

[0071] Other solvents include, for example, dimethyl sulfoxide, sulfolane, γ-butyrolactone, and N-methyl-2-pyrrolidone.

[0072] In the production method (A), the solid content during the reaction is preferably 35 to 95% by mass. If a highly viscous product is produced during the reaction, the reaction can be continued by adding additional solvent. After the reaction is completed, the solvent can be removed or further added as necessary.

[0073] The reaction temperature is preferably within a range that does not decompose the catalyst used. If the reaction temperature is too high, the catalyst may decompose, stopping the reaction or degrading the resulting phosphorus-containing phenoxy resin. If the reaction temperature is too low, the reaction may not proceed sufficiently to achieve the desired molecular weight. Therefore, the reaction temperature is preferably 50 to 230°C, more preferably 120 to 200°C. The reaction time is typically 1 to 12 hours, preferably 3 to 10 hours. When using a low-boiling solvent such as acetone or methyl ethyl ketone, the reaction temperature can be maintained by conducting the reaction under high pressure using an autoclave. If the heat of reaction needs to be removed, this is usually achieved by evaporation, condensation, and reflux of the solvent using the heat of reaction, indirect cooling, or a combination of these.

[0074] Next, the production method (B) of the present invention will be described. Production method (B) is a method for obtaining a phosphorus-containing phenoxy resin (a) represented by formula (6) having a weight-average molecular weight of 10,000 to 200,000, i.e., the phosphorus-containing phenoxy resin of the present invention, by reacting a phosphorus-containing phenoxy resin (a) represented by formula (6) with 0.05 to 2.0 moles of an acylating agent per mole of the alcoholic hydroxyl group equivalent of the phosphorus-containing phenoxy resin (a).

[0075] The raw material phosphorus-containing phenoxy resin (a) is X in the above formula (6). 2 It essentially contains a dioxy group represented by the above formula (2). This phosphorus-containing phenoxy resin (a) can be obtained by a conventional method. For example, a method (hereinafter referred to as the "single-step method") is used to produce the phosphorus-containing phenoxy resin by reacting a bifunctional phenol compound, which contains a dioxy group represented by formula (2) (sometimes referred to as "phosphorus-containing bifunctional phenol compound"), with an epihalohydrin in the presence of an alkali metal compound. Alternatively, a method (hereinafter referred to as the "two-step method") is used to produce the phosphorus-containing phenoxy resin by reacting a bifunctional epoxy resin containing a dioxy group represented by formula (2) with a bifunctional phenol compound in the presence of a catalyst. While the phosphorus-containing phenoxy resin (a) may be obtained by either method, the two-step method is preferred because phosphorus-containing phenoxy resins are generally easier to obtain by the two-step method than by the one-step method.

[0076] The weight average molecular weight and epoxy equivalent of the phosphorus-containing phenoxy resin (a) can be produced within the desired range by appropriately adjusting the molar ratio of the epihalohydrin and bifunctional phenolic compounds charged in the one-stage process, or by appropriately adjusting the molar ratio of the bifunctional epoxy resins and bifunctional phenolic compounds charged in the two-stage process.

[0077] The bifunctional phenol compound used in the one-step and two-step production processes is preferably a phosphorus-containing bifunctional phenol compound (p1) represented by the following formula (10). The phosphorus-containing bifunctional phenol compound (p1) can be obtained by reacting an organic phosphorus compound (p2) represented by the following formula (9) with a quinone compound using a known synthesis method. Examples of synthesis methods are described in JP-A-60-126293, JP-A-61-236787, and zh. Obshch. Khim, 42(11), pp. 2415-2418 (1972), but are not limited to these methods.

[0078] [ka] In the formula, symbols common to formula (2) or formula (3) have the same meanings as those in the formula.

[0079] Other bifunctional phenolic compounds may also be used in combination as long as the objectives of the present invention are not impaired. Examples of bifunctional phenolic compounds that may be used in combination include bisphenols such as bisphenol A, bisphenol F, bisphenol S, bisphenol B, bisphenol E, bisphenolacetophenone, bisphenolfluorene, dihydroxybiphenyl ether, and dihydroxybiphenyl thioether; biphenols; monocyclic bifunctional phenols such as catechol, resorcinol, and hydroquinone; dihydroxynaphthalenes such as 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene; and 1,1-bi-2-naphthol. These may also be substituted with a non-detrimental substituent such as an alkyl group or an aryl group. Multiple types of these bifunctional phenolic compounds may also be used in combination.

[0080] First, the one-stage method will be described. In the one-step process, 0.985 to 1.015 moles, preferably 0.99 to 1.012 moles, and more preferably 0.995 to 1.01 moles, of epihalohydrin are reacted with 1 mole of bifunctional phenolic compounds in a non-reactive solvent in the presence of an alkali metal compound, and the condensation reaction is carried out until the epihalohydrin is consumed and the weight-average molecular weight reaches 10,000 or more, thereby obtaining phenoxy resin (a). After completion of the reaction, the by-product salt must be removed by filtration or washing with water. Examples of the alkali metal compound include the same alkali metal compounds as those used in the production of the bifunctional epoxy resin represented by formula (4) used in production method (A) of the present invention.

[0081] This reaction can be carried out under normal pressure or under reduced pressure. The reaction temperature is preferably 20 to 200°C, more preferably 30 to 170°C, even more preferably 40 to 150°C, and particularly preferably 50 to 100°C, when carried out under normal pressure. The reaction temperature is preferably 20 to 100°C, more preferably 30 to 90°C, and even more preferably 35 to 80°C, when carried out under reduced pressure. A reaction temperature within this range makes it difficult for side reactions to occur and facilitates the reaction to proceed. The reaction pressure is usually normal pressure. Furthermore, when heat of reaction needs to be removed, this is usually achieved by evaporation, condensation, and reflux of the solvent used, indirect cooling, or a combination of these.

[0082] As the reactive solvent, in addition to the reaction solvents exemplified in the production method (A) of the present invention, alcohols such as ethanol, isopropyl alcohol, butyl alcohol, etc. may be used. Only one type may be used, or two or more types may be used in combination.

[0083] Next, the two-stage method will be described. As the bifunctional epoxy resin serving as the raw material epoxy resin in the two-stage process, the same bifunctional epoxy resin as that represented by the above formula (4) used in the production method (A) of the present invention is used.

[0084] The bifunctional epoxy resin used as the raw material for the two-stage process is preferably the bifunctional epoxy resin represented by the above formula (4). However, other bifunctional epoxy resins may be used in combination as long as the objectives of the present invention are not impaired. Examples of bifunctional epoxy resins that can be used in combination include bisphenol-type epoxy resins such as bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, bisphenol S-type epoxy resins, bisphenolacetophenone-type epoxy resins, diphenyl sulfide-type epoxy resins, diphenyl ether-type epoxy resins, and bisphenolfluorenone-type epoxy resins; monocyclic bifunctional phenol diglycidyl ethers such as biphenol-type epoxy resins and hydroquinone-type epoxy resins; dihydroxynaphthalene-type epoxy resins; diphenyldicyclopentadiene-type epoxy resins; alkylene glycol-type epoxy resins; and aliphatic cyclic epoxy resins. These epoxy resins may be substituted with non-detrimental substituents such as alkyl groups and aryl groups. Multiple types of these epoxy resins may be used in combination.

[0085] In the two-stage process, a catalyst can be used, and any compound having catalytic activity that promotes the reaction between the epoxy group and the phenolic hydroxyl group can be used. Examples include the same catalysts as those exemplified in Production Method (A) of the present invention. The alkali metal compounds used in the production of the bifunctional epoxy resin represented by formula (4) above can also be used. These catalysts may be used alone or in combination of two or more. The amount used is also the same as that exemplified in Production Method (A) of the present invention.

[0086] In the two-stage process, a solvent may be used. Any solvent may be used as long as it dissolves the phosphorus-containing phenoxy resin and does not adversely affect the reaction. For example, the same solvents as those exemplified in the production method (A) of the present invention may be used. These solvents may be used alone or in combination of two or more.

[0087] The amount of solvent used can be appropriately selected depending on the reaction conditions. For example, in the case of a two-stage process, a solids concentration of 35 to 95% by mass is preferred. If a highly viscous product is produced during the reaction, the reaction can be continued by adding solvent during the reaction. After the reaction is complete, the solvent can be removed by distillation or the like, or more solvent can be added, as necessary.

[0088] The reaction temperature is maintained within a range that does not decompose the catalyst used. If the reaction temperature is too high, the catalyst may decompose, stopping the reaction or degrading the resulting phosphorus-containing phenoxy resin. If the reaction temperature is too low, the reaction may not proceed sufficiently to achieve the desired molecular weight. Therefore, the reaction temperature is preferably 50 to 230°C, more preferably 100 to 210°C, and even more preferably 120 to 200°C. The reaction time is typically 1 to 12 hours, with 3 to 10 hours being preferred. When using low-boiling solvents such as acetone or methyl ethyl ketone, the reaction temperature can be maintained by conducting the reaction under high pressure using an autoclave. If the heat of reaction needs to be removed, this is typically accomplished by evaporation, condensation, and reflux of the solvent using the reaction heat, indirect cooling, or a combination of these.

[0089] The phosphorus-containing phenoxy resin of the present invention can be obtained by acylation of the hydroxyl groups in the phosphorus-containing phenoxy resin (a) represented by the above formula (6) obtained in this manner. Acylation can be carried out not only by direct esterification but also by methods such as transesterification.

[0090] Examples of the acid component used in the acylation include organic acids such as acetic acid, propionic acid, butyric acid, isobutyric acid, pentanoic acid, octanoic acid, caprylic acid, lauric acid, stearic acid, oleic acid, benzoic acid, t-butylbenzoic acid, hexahydrobenzoic acid, phenoxyacetic acid, acrylic acid, and methacrylic acid, as well as acid anhydrides, organic acid halides, and organic acid esters. Among these acylating agents, acid anhydrides represented by the following formula (7) are preferred.

[0091] [ka] In the formula, Z 2 is an acyl group having a hydrocarbon group having 1 to 20 carbon atoms.

[0092] Examples of organic acid anhydrides include acetic anhydride, benzoic anhydride, and phenoxyacetic anhydride. Examples of organic acid esters include methyl acetate, ethyl acetate, butyl acetate, methyl benzoate, and ethyl benzoate. Examples of organic acid halides include acetic acid chloride, benzoic acid chloride, and phenoxyacetic acid chloride. Acid anhydrides such as acetic anhydride and benzoic anhydride are more preferred in terms of eliminating the need for water washing after esterification and avoiding the inclusion of halogens, which are undesirable in electrical materials applications.

[0093] The compound used for esterification is preferably an organic acid halide such as acetic acid chloride, benzoic acid chloride, or phenoxyacetic acid chloride, or an acid halide or an organic acid anhydride such as acetic anhydride, benzoic acid anhydride, or phenoxyacetic acid anhydride, and more preferably an acid anhydride such as acetic anhydride or benzoic acid anhydride, since this does not require washing with water after esterification and avoids contamination with halogens, which are undesirable in electrical materials applications.

[0094] The charge ratio of an acid component such as the organic acid, acid anhydride of an organic acid, halide of an organic acid, or ester of an organic acid used for esterifying the hydroxyl groups of the phosphorus-containing phenoxy resin (a) when reacting with the phenoxy resin (a) may be the same as the target esterification ratio, or when the reactivity is low, the acid component may be charged in excess relative to the hydroxyl groups, and after the reaction reaches the target esterification ratio, the unreacted acid component may be removed.

[0095] Direct esterification with an acid component can be carried out while dehydrating using various esterification catalysts, such as acid catalysts (e.g., paratoluenesulfonic acid, phosphoric acid, etc.) or metal catalysts (e.g., tetraisopropyl titanate, tetrabutyl titanate, dibutyltin oxide, dioctyltin oxide, zinc chloride, etc.) It is usually carried out in a nitrogen atmosphere at 100 to 250°C, more preferably 130 to 230°C.

[0096] When an acid halide or an acid anhydride is used for esterification, the generated acid can be removed by any of the following methods, or a combination of these: a method of neutralizing with a basic compound and then filtering the salt; a method of neutralizing with a basic compound and then washing with water; a method of washing with water without neutralization; or a method of removing the acid by distillation or adsorption. When an acid having a boiling point lower than that of the reaction solvent is to be removed, it is preferable to remove it by distillation.

[0097] When the phosphorus-containing phenoxy resin (a) is esterified by transesterification, it is generally desirable to carry out the esterification under a nitrogen atmosphere while dealcoholizing the resin using a known esterification catalyst, such as dibutyltin oxide, dioctyltin oxide, a stannoxane catalyst, tetraisopropyl titanate, tetrabutyl titanate, lead acetate, zinc acetate, or antimony trioxide; an acid catalyst such as hydrochloric acid, sulfuric acid, phosphoric acid, or sulfonic acid; or a basic catalyst such as lithium hydroxide or sodium hydroxide.

[0098] In the production method (B) of the present invention, a reaction solvent may be used. Any solvent that dissolves the phosphorus-containing phenoxy resin may be used. Examples include the solvents exemplified in the production method (A) of the present invention. These solvents may be the same as or different from those used in the preparation of the phosphorus-containing phenoxy resin (a). Furthermore, only one type may be used, or two or more types may be used in combination.

[0099] The resin composition of the present invention is a resin composition containing at least the phosphorus-containing phenoxy resin of the present invention and a curing agent. Furthermore, various additives such as epoxy resins, inorganic fillers, coupling agents, and antioxidants can be appropriately blended into the resin composition of the present invention as needed. The resin composition of the present invention provides a cured product that satisfies the various physical properties required for various applications.

[0100] A resin composition can be prepared by blending a curing agent with the phosphorus-containing phenoxy resin of the present invention. In the present invention, the curing agent refers to a substance that contributes to the crosslinking reaction and / or chain extension reaction with the phosphorus-containing phenoxy resin. In the present invention, even substances that are usually called "curing accelerators" are considered to be curing agents as long as they contribute to the crosslinking reaction and / or chain extension reaction of the phosphorus-containing phenoxy resin.

[0101] The content of the curing agent in the resin composition of the present invention is preferably 0.1 to 100 parts by mass in terms of solid content, more preferably 80 parts by mass or less, and even more preferably 60 parts by mass or less, per 100 parts by mass of the solid content of the phosphorus-containing phenoxy resin of the present invention.

[0102] When the resin composition of the present invention contains an epoxy resin described below, the weight ratio of the solid content of the phosphorus-containing phenoxy resin of the present invention to the epoxy resin is 99 / 1 to 1 / 99. In the present invention, the "solid content" refers to the components excluding the solvent, and includes not only solid phosphorus-containing phenoxy resins and epoxy resins, but also semi-solid and viscous liquids. Furthermore, the "resin component" refers to the total of the phosphorus-containing phenoxy resin of the present invention and the epoxy resin described below.

[0103] The curing agent used in the resin composition of the present invention is not particularly limited, and any commonly known curing agent for epoxy resins can be used. From the viewpoint of improving heat resistance, preferred curing agents include phenol-based curing agents, amide-based curing agents, imidazoles, and active ester-based curing agents. These curing agents may be used alone or in combination of two or more.

[0104] Examples of phenolic curing agents include bisphenol A, bisphenol F, 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl ether, 1,4-bis(4-hydroxyphenoxy)benzene, 1,3-bis(4-hydroxyphenoxy)benzene, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, phenol novolac, bisphenol A novolac, o-cresol novolac, m-cresol novolac, p-cresol novolac, xylenol novolac, poly-p-hydroxystyrene, hydroquinone, resorcinol, catechol, t-butylcatechol, t-butylhydroquinone, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, Examples of the allylated phenol include 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated products or polyallylated products of the above dihydroxynaphthalenes, allylated bisphenol A, allylated bisphenol F, allylated phenol novolak, and allylated pyrogallol.

[0105] Examples of the amide-based curing agent include dicyandiamide and its derivatives, polyamide resins, and the like.

[0106] Examples of imidazoles include 2-phenylimidazole, 2-ethyl-4(5)-methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazole] Examples of suitable imidazoles include 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resins with the above imidazoles. Note that, since imidazoles have catalytic activity, they can generally be classified as curing accelerators, which will be described later, but in the present invention they are classified as curing agents.

[0107] Examples of active ester curing agents include compounds having two or more highly reactive ester groups per molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. Among these, phenol esters obtained by reacting a carboxylic acid compound with an aromatic compound having a phenolic hydroxyl group are more preferred. Specific examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of aromatic compounds having a phenolic hydroxyl group include catechol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyldiphenol, and phenol novolac.

[0108] Examples of other curing agents that can be used in the resin composition of the present invention include amine-based curing agents, acid anhydride-based curing agents, tertiary amines, organic phosphines, phosphonium salts, tetraphenylboron salts, organic acid dihydrazides, boron halide amine complexes, polymercaptan-based curing agents, isocyanate-based curing agents, blocked isocyanate-based curing agents, etc. These other curing agents may be used alone, or two or more may be mixed in any combination and ratio.

[0109] The resin composition of the present invention can contain an epoxy resin. The use of an epoxy resin can compensate for insufficient physical properties and improve various physical properties. The epoxy resin preferably has two or more epoxy groups in the molecule, and more preferably has three or more epoxy groups. Examples include polyglycidyl ether compounds, polyglycidyl amine compounds, polyglycidyl ester compounds, alicyclic epoxy compounds, and other modified epoxy resins. These epoxy resins may be used alone, or two or more types of epoxy resins of the same type may be used in combination, or different types of epoxy resins may be used in combination.

[0110] Examples of the polyglycidyl ether compound include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, bisphenol Z type epoxy resins, bisphenol fluorene type epoxy resins, diphenyl sulfide type epoxy resins, diphenyl ether type epoxy resins, naphthalene type epoxy resins, hydroquinone type epoxy resins, resorcinol type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, alkyl novolac type epoxy resins, styrenated phenol novolac type epoxy resins, bisphenol novolac type epoxy resins, naphthol novolac type epoxy resins, phenol aralkyl type epoxy resins, β-naphthol aralkyl type epoxy resins, naphthalenediol aralkyl type epoxy resins, α-naphthol aralkyl type epoxy resins, biphenyl aralkyl phenol type epoxy resins, biphenyl type epoxy resins, triphenylmethane type epoxy resins, dicyclopentadiene type epoxy resins, alkylene glycol type epoxy resins, and various epoxy resins such as aliphatic cyclic epoxy resins.

[0111] Examples of polyglycidylamine compounds include diaminodiphenylmethane type epoxy resins, metaxylenediamine type epoxy resins, 1,3-bisaminomethylcyclohexane type epoxy resins, isocyanurate type epoxy resins, aniline type epoxy resins, hydantoin type epoxy resins, and aminophenol type epoxy resins.

[0112] Examples of polyglycidyl ester compounds include dimer acid type epoxy resins, hexahydrophthalic acid type epoxy resins, and trimellitic acid type epoxy resins.

[0113] Examples of the alicyclic epoxy compound include aliphatic cyclic epoxy resins such as CELLOXIDE 2021 (manufactured by Daicel Chemical Industries, Ltd.).

[0114] Other modified epoxy resins include, for example, urethane-modified epoxy resins, oxazolidone ring-containing epoxy resins, epoxy-modified polybutadiene rubber derivatives, carboxyl-terminated butadiene nitrile rubber (CTBN)-modified epoxy resins, polyvinylarene polyoxides (e.g., divinylbenzene dioxide, trivinylnaphthalene trioxide, etc.), and phosphorus-containing phenoxy resins.

[0115] When the phosphorus-containing phenoxy resin of the present invention and an epoxy resin are used in the resin composition of the present invention, the amount of the epoxy resin in the total components of the phosphorus-containing phenoxy resin and the epoxy resin as solids is preferably 1 to 99 mass%, more preferably 5 to 97 mass%, even more preferably 10 to 95 mass%, and still more preferably 10 to 90 mass%. By having the epoxy resin in the above amount, the heat resistance and mechanical strength of a cured product made from the resin composition of the present invention can be improved.

[0116] The resin composition of the present invention may contain a solvent or reactive diluent to adjust the viscosity of the resin composition appropriately when handling the composition to form a coating film. In the resin composition of the present invention, the solvent or reactive diluent is used to ensure the ease of handling and workability when molding the resin composition, and there is no particular limit to the amount used. In the present invention, the term "solvent" and the aforementioned term "solvent" are used separately depending on the form of use, but the same or different substances may be used independently.

[0117] Examples of solvents that may be contained in the resin composition of the present invention include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone, etc., esters such as ethyl acetate, ethers such as ethylene glycol monomethyl ether, amides such as N,N-dimethylformamide, N,N-dimethylacetamide, etc., alcohols such as methanol, ethanol, etc., alkanes such as hexane, cyclohexane, etc., aromatics such as toluene, xylene, etc. The above-mentioned solvents may be used alone, or two or more may be mixed in any combination and ratio.

[0118] Examples of reactive diluents include monofunctional glycidyl ethers such as allyl glycidyl ether, bifunctional glycidyl ethers such as propylene glycol diglycidyl ether, polyfunctional glycidyl ethers such as trimethylolpropane polyglycidyl ether, glycidyl esters, and glycidyl amines.

[0119] These solvents or reactive diluents are preferably used in an amount of 90% by mass or less as nonvolatile matter, and the appropriate type and amount are appropriately selected depending on the application. For example, for printed wiring board applications, polar solvents with a boiling point of 160°C or less, such as methyl ethyl ketone, acetone, and 1-methoxy-2-propanol, are preferred, and the amount used is preferably 40 to 80% by mass as nonvolatile matter. For adhesive film applications, for example, ketones, acetate esters, carbitols, aromatic hydrocarbons, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone are preferred, and the amount used is preferably 30 to 60% by mass as nonvolatile matter.

[0120] If necessary, a curing accelerator (excluding those included in the term "curing agent") may be used in the resin composition of the present invention. Examples of the curing accelerator include imidazoles, tertiary amines, phosphorus compounds such as phosphines, metal compounds, Lewis acids, and amine complex salts. These curing accelerators may be used alone or in combination of two or more.

[0121] The amount of curing accelerator to be added may be appropriately selected depending on the intended use, but is preferably 0.01 to 15 parts by mass, more preferably 0.01 to 10 parts by mass, more preferably 0.05 to 8 parts by mass, and even more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the epoxy resin component in the resin composition. Use of a curing accelerator can lower the curing temperature and shorten the curing time.

[0122] In order to improve the flame retardancy of the resulting cured product, various known flame retardants can be used in the resin composition of the present invention, as long as the reliability is not reduced. Usable flame retardants include, for example, halogen-based flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, silicone-based flame retardants, inorganic flame retardants, and organic metal salt-based flame retardants. From an environmental perspective, halogen-free flame retardants are preferred, and phosphorus-based flame retardants are particularly preferred. These flame retardants may be used alone, or two or more of the same type of flame retardants may be used in combination, or different types of flame retardants may be used in combination.

[0123] The resin composition of the present invention may contain components other than those listed above (sometimes referred to as "other components" in the present invention) for the purpose of further improving its functionality. Examples of such other components include fillers, thermoplastic resins, thermosetting resins, photocurable resins, ultraviolet inhibitors, antioxidants, coupling agents, plasticizers, fluxes, thixotropic agents, smoothing agents, colorants, pigments, dispersants, emulsifiers, elasticity reducing agents, release agents, antifoaming agents, and ion trapping agents.

[0124] Examples of fillers include inorganic fillers such as fused silica, crystalline silica, alumina, silicon nitride, boron nitride, aluminum nitride, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, boehmite, talc, mica, clay, calcium carbonate, magnesium carbonate, barium carbonate, zinc oxide, titanium oxide, magnesium oxide, magnesium silicate, calcium silicate, zirconium silicate, barium sulfate, and carbon; fibrous fillers such as carbon fiber, glass fiber, alumina fiber, silica alumina fiber, silicon carbide fiber, polyester fiber, cellulose fiber, aramid fiber, and ceramic fiber; and fine particle rubber.

[0125] The resin composition of the present invention may contain a thermoplastic resin other than the phosphorus-containing phenoxy resin of the present invention. Examples of the thermoplastic resin include phosphorus-containing phenoxy resins other than those of the present invention, polyurethane resins, polyester resins, polyethylene resins, polypropylene resins, polystyrene resins, ABS resins, AS resins, vinyl chloride resins, polyvinyl acetate resins, polymethyl methacrylate resins, polycarbonate resins, polyacetal resins, cyclic polyolefin resins, polyamide resins, thermoplastic polyimide resins, polyamideimide resins, polytetrafluoroethylene resins, polyetherimide resins, polyphenylene ether resins, modified polyphenylene ether resins, polyethersulfone resins, polysulfone resins, polyetheretherketone resins, polyphenylene sulfide resins, and polyvinyl formal resins. From the viewpoint of compatibility, phosphorus-containing phenoxy resins other than those of the present invention are preferred, and from the viewpoint of low dielectric properties, polyphenylene ether resins and modified polyphenylene ether resins are preferred.

[0126] Examples of other components include organic pigments such as quinacridone, azo, and phthalocyanine pigments, inorganic pigments such as titanium oxide, metal foil pigments, and anti-rust pigments, ultraviolet absorbers such as hindered amine, benzotriazole, and benzophenone, antioxidants such as hindered phenol, phosphorus, sulfur, and hydrazide, release agents such as stearic acid, palmitic acid, zinc stearate, and calcium stearate, and additives such as leveling agents, rheology control agents, pigment dispersants, anti-cracking agents, and anti-foaming agents. The amount of these other components added is preferably 0.01 to 20% by mass based on the total solid content of the resin composition.

[0127] The resin composition of the present invention can be obtained by uniformly mixing the above-mentioned components. Resin compositions containing a phosphorus-containing phenoxy resin, a curing agent, and, if necessary, various other components can be easily cured using methods similar to those known in the art. This cured product exhibits excellent balance of low moisture absorption, dielectric properties, heat resistance, adhesion, and other properties, and exhibits good cured physical properties. "Curing" here refers to intentionally curing the resin composition using heat and / or light, and the degree of curing can be controlled depending on the desired physical properties and application. The degree of curing may be fully cured or semi-cured, and is not particularly limited; however, the reaction rate of the curing reaction between the epoxy group and the curing agent is typically 5 to 95%.

[0128] The resin composition of the present invention can be cured to obtain a cured product by the same method as for known epoxy resin compositions. Methods for obtaining a cured product include those similar to those for known epoxy resin compositions, such as casting, injection, potting, dipping, drip coating, transfer molding, and compression molding, as well as laminating the resin in the form of a resin sheet, resin-coated copper foil, or prepreg, followed by heating and pressure curing to obtain a laminate. The curing temperature is typically in the range of 80 to 300°C, and the curing time is typically about 10 to 360 minutes. This heating is preferably carried out in two stages: a primary heating step at 80 to 180°C for 10 to 90 minutes, followed by a secondary heating step at 120 to 200°C for 60 to 150 minutes. Furthermore, for formulations whose glass transition temperature (Tg) exceeds the secondary heating temperature, a tertiary heating step at 150 to 280°C for 60 to 120 minutes is preferably carried out. Such secondary and tertiary heating steps can reduce poor curing. When producing a semi-cured resin product such as a resin sheet, a resin-coated copper foil, or a prepreg, the curing reaction of the resin composition is usually allowed to proceed to an extent that the shape can be maintained by heating, etc. When the resin composition contains a solvent, most of the solvent is usually removed by techniques such as heating, decompression, or air drying, but 5% by mass or less of the solvent may remain in the semi-cured resin product.

[0129] The prepreg obtained using the resin composition of the present invention will now be described. The sheet-like substrate can be, but is not limited to, a woven or nonwoven fabric made of inorganic fibers such as glass, or organic fibers such as polyester, polyamine, polyacrylic, polyimide, Kevlar, or cellulose. The method for producing a prepreg from the resin composition of the present invention and the substrate is not particularly limited. For example, the substrate can be immersed in a resin varnish obtained by adjusting the viscosity of the resin composition with a solvent, and then heated and dried to semi-cure (B-stage) the resin component. For example, the prepreg can be obtained by heating and drying at 100 to 200°C for 1 to 40 minutes. The resin content in the prepreg is preferably 30 to 80% by mass.

[0130] A method for producing a laminate using the prepreg or insulating adhesive sheet of the present invention will be described. When forming a laminate using prepreg, one or more prepregs are laminated, and metal foil is placed on one or both sides to form a laminate, which is then heated and pressed to form an integrated laminate. The metal foil used here can be a single, alloy, or composite metal foil of copper, aluminum, brass, nickel, or the like. The conditions for heating and pressing the laminate can be appropriately adjusted to cure the resin composition. However, if the pressure is too low, air bubbles may remain inside the resulting laminate, resulting in reduced electrical properties. Therefore, it is desirable to pressurize under conditions that satisfy moldability. For example, a temperature of 160 to 220°C and a pressure of 49.0 to 490.3 N / cm are used. 2 (5-50kgf / cm 2 ) and heating time can be set from 40 to 240 minutes.

[0131] Furthermore, a multilayer board can be produced using the single-layer laminate thus obtained as an inner layer material. In this case, a circuit is first formed on the laminate by an additive method, a subtractive method, or the like, and the surface of the formed circuit is then treated with an acid solution for blackening to obtain an inner layer material. An insulating layer is formed on one or both circuit-forming surfaces of this inner layer material using a prepreg or an insulating adhesive sheet, and a conductor layer is formed on the surface of the insulating layer to form a multilayer board.

[0132] When forming an insulating layer using an insulating adhesive sheet, a laminate is formed by placing an insulating adhesive sheet on the circuit-forming surfaces of multiple inner layer materials. Alternatively, a laminate is formed by placing an insulating adhesive sheet between the circuit-forming surfaces of the inner layer materials and metal foil. This laminate is then heated and pressurized to form an integral molding, thereby forming the cured insulating adhesive sheet as an insulating layer and forming a multilayer inner layer material. Alternatively, the inner layer material and the metal foil serving as the conductor layer are combined to form the cured insulating adhesive sheet as an insulating layer. Here, the metal foil can be the same as that used in the laminate used as the inner layer material. Furthermore, the hot and pressure molding can be carried out under the same conditions as those for molding the inner layer material. When forming an insulating layer by applying a resin composition to a laminate, the resin for forming the circuit on the outermost layer of the inner layer material is preferably applied to a thickness of 5 to 100 μm with the above-mentioned resin composition, and then heated and dried at 100 to 200°C for 1 to 90 minutes to form a sheet. This is generally formed by a method called a casting method. The thickness after drying is preferably formed to 5 to 80 μm. A printed wiring board can be formed by further forming via holes and circuits on the surface of the multilayer laminate thus formed by an additive method or a subtractive method. Furthermore, by repeating the above process using this printed wiring board as an inner layer material, it is possible to form a multi-layer laminate.

[0133] When forming an insulating layer using prepreg, one or more prepreg sheets are placed on the circuit-forming surface of the inner layer material, and a metal foil is placed on the outside of the prepreg to form a laminate. This laminate is then heated and pressurized to form an integral molding, whereby the cured prepreg is formed as an insulating layer and the outer metal foil is formed as a conductor layer. Here, the metal foil may be the same as that used in the laminate used as the inner layer material. The hot-press molding can be carried out under the same conditions as those for molding the inner layer material. The surface of the multilayer laminate thus molded can be further subjected to via hole formation and circuit formation by an additive method or a subtractive method to mold a printed wiring board. Furthermore, by repeating the above process using this printed wiring board as an inner layer material, it is possible to form a multi-layer board with even more layers.

[0134] The cured product and laminate for electric / electronic circuits obtained from the resin composition of the present invention have excellent flame retardancy and strength. [Example]

[0135] The present invention will be explained in more detail below based on examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified, parts represent parts by mass and % represents % by mass. Analytical and measurement methods are shown below. Furthermore, the unit of various equivalents is g / eq.

[0136] (1) Weight average molecular weight (Mw) and number average molecular weight (Mn): The Mw was determined by GPC measurement. Specifically, a HLC8320 GPC (Tosoh Corporation) was used, equipped with columns (TSKgel SuperH-H, SuperH2000, SuperHM-H, SuperHM-H, all Tosoh Corporation) in series. The column temperature was 40°C. The eluent was DMF (containing 20 mM lithium bromide) at a flow rate of 0.3 mL / min, and a refractive index detector was used. 0.1 g of solids was dissolved in 10 mL of DMF and filtered through a 0.45 μm microfilter. 20 μL of the sample was used. Mw was calculated from a calibration curve obtained from standard polyethylene oxides (Tosoh Corporation: SE-2, SE-5, SE-8, SE-15, SE-30, SE-70, and SE-150). Data processing was performed using a GPC8020 Model II version 6.00 (Tosoh Corporation).

[0137] (2) Epoxy equivalent: Measurements were carried out in accordance with JIS K 7236. Specifically, a potentiometric titrator was used, cyclohexanone was used as the solvent, tetraethylammonium bromide acetate solution was added, and a 0.1 mol / L perchloric acid-acetic acid solution was used. For solvent-diluted products (resin varnishes), the solid content was calculated from the nonvolatile content.

[0138] (3) Phosphorus content: Sulfuric acid, hydrochloric acid, and perchloric acid were added to phosphorus-containing phenoxy resin, and the resin was heated and wet-ashed to convert all phosphorus atoms to orthophosphate. Metavanadate and molybdate were reacted in the sulfuric acid solution, and the absorbance of the resulting phosphorus vanadomolybdate complex was measured at 420 nm. The phosphorus content (P / resin) was calculated using a pre-prepared calibration curve and expressed as a percentage. For solvent-diluted products (resin varnishes), the solids content was calculated from the nonvolatile content.

[0139] (4) Nonvolatile content: Measurement was performed in accordance with JIS K 7235. The drying temperature was 200°C and the drying time was 60 minutes.

[0140] (5) Glass transition temperature (Tg): Measurements were performed in accordance with IPC-TM-650 2.4.25.c. Specifically, a 4 mm thick, 3 mm diameter sample was measured using a differential scanning calorimeter (EXSTAR6000 DSC6200, manufactured by SII NanoTechnology Inc.) in the range of 20 to 280°C at a temperature increase rate of 10°C / min for two cycles, and the glass transition temperature (Tmg) was expressed as the midpoint of the second scan measurement chart.

[0141] (6) Flame retardancy: Evaluation was carried out using the V test of UL94V (Underwriters Laboratories Inc.). Test specimens were prepared in accordance with UL94-V using the method described below. Five test specimens were tested and rated as V-0, V-1, or V-2, based on the standard's rating criteria, based on the total duration of flaming combustion after the first and second flame exposure (five specimens were each exposed to flame twice, for a total of 10 exposures). V-0 represents the best flame retardancy, with V-1 and V-2 rankings indicating worse flame retardancy. However, specimens that burned completely were marked with an X. Resin films were also evaluated using the vertical method in accordance with UL94VTM. The evaluation was rated as VTM-0, VTM-1, and VTM-2. VTM-0 was the best in terms of flame retardancy, followed by VTM-1 and VTM-2. However, those that burned completely were marked with an X.

[0142] (7) Solubility: A phosphorus-containing phenoxy resin was made into a resin varnish with a resin content of 30% using cyclohexanone, and the same amount of bisphenol A epoxy resin (YD-128, manufactured by Nippon Steel Chemical & Material Co., Ltd.) was added. The mixture was shaken for 1 hour in a shaker and then left to stand in a thermostatic bath at 25°C for 24 hours, after which the condition was visually inspected. The evaluation is as follows: 〇: Uniform and transparent ×: Cloudy or separated

[0143] (8) Strength: The test was conducted in accordance with the JIK K 7110 standard using unnotched test pieces. The strength was 100 kJ / m 2 If it is less than 100kJ / m 2 The above is considered a pass.

[0144] The abbreviations used in the examples and comparative examples are as follows:

[0145] A1: Bisphenol A epoxy resin (Nippon Steel Chemical & Material Co., Ltd., YD-128, epoxy equivalent 186, m≒0.09) A2: 3,3',5,5'-tetramethyl-4,4'-biphenol epoxy resin (Mitsubishi Chemical Corporation, YX-4000, epoxy equivalent 196, m≒0.11)

[0146] B1: 10-(2,5-diacetoxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (active equivalents 204) B2: 10-(2,7-diacetoxynaphthyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (active equivalents 229) B3: 2,2-bis(4-acetoxyphenyl)propane (Tokyo Chemical Industry Co., Ltd., active equivalent: 156)

[0147] [Phenol compounds] C1: 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (Sanko Chemical Co., Ltd., HCA-HQ, hydroxyl equivalent: 162) C2: 10-(2,7-dihydroxynaphthyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (Sanko Chemical Co., Ltd., HCA=NQ, hydroxyl equivalent: 187)

[0148] [catalyst] D1: N,N'-dimethylaminopyridine (Tokyo Chemical Industry Co., Ltd.) D2: 2-ethyl-4-methylimidazole (Curesol 2E4MZ, manufactured by Shikoku Chemicals Corporation)

[0149] [Solvents] S1: Cyclohexanone

[0150] [Acid anhydride] E1: Acetic anhydride (Fujifilm Wako Pure Chemical Industries, Ltd.) E2: Benzoic anhydride (Tokyo Chemical Industry Co., Ltd.)

[0151] [Hardening agent] H1: Dicyandiamide (manufactured by Nippon Carbide Industries Co., Ltd., product name: DIHARD, active hydrogen equivalent: 21)

[0152] Synthesis Example 1 A glass reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet, condenser, and dropping device was charged with 100 parts of C1, 315 parts of E1, 0.05 parts of dibutyltin maleate, and 186 parts of acetic acid at room temperature, and the mixture was heated to 110°C with stirring under nitrogen gas flow, and reacted for 2 hours. Thereafter, the mixture was dried under reduced pressure at 130°C and 1.3 kPa (10 torr) for 3 hours, yielding 98 parts of B1.

[0153] Synthesis Example 2 The glass reaction vessel was charged with 100 parts of C2, 272 parts of E1, 0.04 parts of dibutyltin maleate, and 160 parts of acetic acid at room temperature, and the mixture was heated to 110°C while stirring under nitrogen gas flow, and reacted for 2 hours. Thereafter, the mixture was dried under reduced pressure at 130°C and 10 torr for 3 hours, yielding 98 parts of B2.

[0154] Example 1 A glass reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet, condenser, and dropping device was charged with 100 parts of A1, 104 parts of B1, and 88 parts of S1 at room temperature, and the mixture was heated to 130°C while stirring and nitrogen gas was passed through. 0.2 parts of C1 was added, and the mixture was then heated to 145°C and reacted at that temperature for 7 hours. 389 parts of S1 was used as a dilution solvent for dilution and mixing, yielding a phosphorus-containing phenoxy resin varnish (R1) with a nonvolatile content of 30%.

[0155] Examples 2 to 7, Comparative Examples 1 to 2 A phosphorus-containing phenoxy resin varnish was obtained in the same manner as in Example 1, using the amounts (parts) of each raw material shown in Tables 1 and 2. The molar ratios in the tables represent the molar ratios of the difunctional epoxy resin to the diester compound and the difunctional phenol compound, and varnish represents the phosphorus-containing phenoxy resin varnish.

[0156] [Table 1]

[0157] [Table 2]

[0158] Example 8 100 parts (40 parts solids) of the phosphorus-containing phenoxy resin varnish (RH2) obtained in Comparative Example 2 and 600 parts of S1 were blended, and the mixture was heated to 100°C, after which 6 parts of E1 were added and reacted for 4 hours. The resulting resin varnish was added to methanol, and the precipitated insoluble matter was filtered off. The filtrate was then dried in a vacuum dryer at 150°C and 0.4 kPa (3 torr) for 1 hour to obtain a phosphorus-containing phenoxy resin. 99 parts of S1 were added to the resulting phosphorus-containing phenoxy resin and dissolved uniformly to obtain a phosphorus-containing phenoxy resin varnish (R8) with a nonvolatile content of 30%.

[0159] Example 9 A phosphorus-containing phenoxy resin varnish (R9) was obtained in the same manner as in Example 8, except that E1 was used in an amount of 14 parts and the dilution solvent S1 was used in an amount of 105 parts.

[0160] Example 10 A phosphorus-containing phenoxy resin varnish (R10) was obtained by the same procedure as in Example 8, except that 33 parts of E2 was used instead of E1 and 120 parts of the dilution solvent S1.

[0161] The phosphorus-containing phenoxy resin varnishes R1 to R10 obtained in Examples 1 to 10 and the phosphorus-containing phenoxy resin varnishes RH1 to RH2 obtained in Comparative Examples 1 and 2 were dried in a vacuum oven at 200°C and 0.4 kPa (3 torr) for 1 hour, and then vacuum-pressed at 230°C and 2 MPa for 1 hour to obtain resin films. The epoxy equivalent, phosphorus content, Mw, and solubility of the phosphorus-containing phenoxy resin varnishes were measured, and the Tg and flame retardancy of the resin films were measured. The results are shown in Table 3. In the table, the "acylation ratio" represents the content (mol %) of acyl groups in the total Z in formula (1).

[0162] [Table 3]

[0163] Examples 11 to 13 and Comparative Examples 3 and 4 A resin composition was prepared by blending 100 parts (40 parts solids) of the phosphorus-containing phenoxy resin varnish (R1, R2, R6, RH1, RH2) obtained in Examples 1, 2, and 6 and Comparative Examples 1 and 2 with 50 parts of epoxy resin A1, 2.8 parts of curing agent H1, and 0.6 parts of a 20% MEK solution of curing accelerator D2. The resulting resin composition was impregnated into glass cloth (WEA7628XS13, manufactured by Nitto Boseki Co., Ltd., 0.18 mm thick) and then dried for 8 minutes in a hot air circulating oven at 150°C to obtain a B-stage prepreg. Eight and 50 sheets of the resulting prepreg were stacked, and copper foil (3EC, manufactured by Mitsui Mining & Smelting Co., Ltd., 35 μm thick) was layered on top and bottom of the prepreg. The prepreg was then cured in a vacuum press at 130°C for 15 minutes and 170°C for 70 minutes under a pressure of 2 MPa to obtain 1.6 and 10.0 mm thick laminates. Both surfaces of the resulting laminate were etched to obtain test specimens for evaluating flame retardancy and impact strength.

[0164] [Table 4]

[0165] As can be seen from Table 3, the phosphorus-containing phenoxy resin of the present invention has excellent flame retardancy and solubility. Furthermore, as can be seen from Table 4, the cured product made from the phosphorus-containing phenoxy resin composition of the present invention also has excellent flame retardancy and strength.

[0166] The phosphorus-containing phenoxy resin and resin composition of the present invention are applicable to various fields such as adhesives, paints, civil engineering and building materials, and insulating materials for electric and electronic components, and are particularly useful in the electric and electronic fields as insulating casting materials, laminate materials, sealing materials, etc. The phosphorus-containing phenoxy resin and resin composition containing the same of the present invention are suitable for use in multilayer printed wiring boards, laminates for electric and electronic circuits such as capacitors, adhesives such as film adhesives and liquid adhesives, semiconductor sealing materials, underfill materials, interchip fill materials for 3D-LSI, insulating sheets, prepregs, heat dissipation substrates, etc.

Claims

1. A phosphorus-containing phenoxy resin represented by the following formula (1), having a weight average molecular weight of 10,000 to 200,000 and a phosphorus content of 1 to 6 mass %: 【Chemistry 1】 In the formula, X is independently a divalent group containing a dioxy group represented by the following formula (2), and each Y is independently a hydrogen atom, an acyl group having a hydrocarbon group of 1 to 20 carbon atoms, or a glycidyl group. Z is an acyl group having a hydrocarbon group of 1 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of Z is the above acyl group. n is the average number of repeating units and is 15 to 500. 【Chemistry 2】 In the formula, A is a trivalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and W is a phosphorus-containing group represented by formula (3). １ and R ２ are each independently a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom, and may be linear, branched, or cyclic; １ and R ２ may be bonded to form a cyclic structure, and k1 and k2 each independently represent 0 or 1.

2. 2. The phosphorus-containing phenoxy resin according to claim 1, having an epoxy equivalent of 2,000 to 50,000 g / eq.

3. A resin composition comprising the phosphorus-containing phenoxy resin according to claim 1 or 2 and a curing agent.

4. 4. The resin composition according to claim 3, wherein the curing agent is contained in an amount of 0.1 to 100 parts by mass as solid content per 100 parts by mass of the solid content of the phosphorus-containing phenoxy resin.

5. 4. The resin composition according to claim 3, comprising the phosphorus-containing phenoxy resin according to claim 1 or 2, an epoxy resin, and a curing agent, wherein the mass ratio of the solid content of the phosphorus-containing phenoxy resin to the solid content of the epoxy resin is 99 / 1 to 1 / 99.

6. 6. The resin composition according to claim 5, comprising 0.1 to 100 parts by mass of the curing agent as solid content per 100 parts by mass of the total solid content of the phosphorus-containing phenoxy resin and the epoxy resin.

7. The resin composition according to any one of claims 3 to 6, wherein the curing agent is at least one selected from the group consisting of acrylic ester resins, melamine resins, urea resins, phenolic resins, acid anhydride compounds, amine compounds, imidazole compounds, amide compounds, cationic polymerization initiators, organic phosphines, polyisocyanate compounds, blocked isocyanate compounds, and active ester curing agents.

8. A cured product obtained by curing the resin composition according to any one of claims 3 to 7.

9. A laminate for electric / electronic circuits, which is obtained by using the resin composition according to any one of claims 3 to 7.

10. A method for producing a phosphorus-containing phenoxy resin, comprising reacting a bifunctional epoxy resin represented by the following formula (4) with a compound represented by the following formula (5) to obtain a phosphorus-containing phenoxy resin represented by the following formula (1) having a weight-average molecular weight of 10,000 to 200,000 and a phosphorus content of 1 to 6 mass %: 【Transformation 3】 In the formula, G is a glycidyl group, and X １ are independently divalent groups containing a dioxy group represented by the following formula (2), and X in formula (4) and formula (5) １ Among them, the dioxy group represented by formula (2) is included as a whole. １ is an acyl group having a hydrocarbon group having 1 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of the acyl group is the above. １ and m is the average number of repeating units and is 0 to 6. 【Chemistry 4】 In the formula, A is a trivalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and W is a phosphorus-containing group represented by formula (3). １ and R ２ are each independently a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom, and may be linear, branched, or cyclic. １ and R ２ may be bonded to form a cyclic structure, and k1 and k2 each independently represent 0 or 1. 【Transformation 5】 In the formula, X is independently a divalent group containing a dioxy group represented by formula (2) above, and each Y is independently a hydrogen atom, an acyl group having a hydrocarbon group of 1 to 20 carbon atoms, or a glycidyl group. Z is an acyl group having a hydrocarbon group of 1 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of Z is the above acyl group. n is the average number of repeating units and is 15 to 500.

11. A method for producing a phosphorus-containing phenoxy resin, comprising reacting 0.05 moles or more and 2.0 moles or less of an acylating agent with 1 mole of an alcoholic hydroxyl group equivalent of phosphorus-containing phenoxy resin (a) represented by the following formula (6), to obtain a phosphorus-containing phenoxy resin represented by the following formula (1) having a weight-average molecular weight of 10,000 to 200,000 and a phosphorus content of 1 to 6 mass %. 【Transformation 6】 In the formula, X ２ are independently divalent groups containing a dioxy group represented by the following formula (2), and Y ２ are each independently a hydrogen atom or a glycidyl group, and n is the average number of repeating groups, and is 15 to 500. 【Transformation 7】 In the formula, A is a trivalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and W is a phosphorus-containing group represented by formula (3). １ and R ２ are each independently a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom, and may be linear, branched, or cyclic. １ and R ２ may be bonded to form a cyclic structure, and k1 and k2 each independently represent 0 or 1. 【Transformation 8】 In the formula, X and n are respectively X in formula (6). ２ , n are the same as above. Each Y is independently a hydrogen atom, an acyl group having a hydrocarbon group of 1 to 20 carbon atoms, or a glycidyl group. Z is an acyl group having a hydrocarbon group of 1 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of Z is the above acyl group.

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