TWI738994B - Oxazolidone ring-containing epoxy resin, method for producing the thereof, curable resin composition and cured product - Google Patents

Abstract

The present invention provides an epoxy resin composition containing an oxazolidinone ring that is excellent in adhesiveness, dielectric properties, and flame retardancy, and is useful as an epoxy resin for electronic circuit boards. An epoxy resin composition containing an oxazolidinone ring, which is obtained from an epoxy resin (a) and an isocyanate compound (b), and the epoxy resin (a) contains a bisphenol type represented by the following formula (1) The epoxy resin (a1) and the biphenyl type epoxy resin (a2) represented by the following formula (2), and the epoxy resin (a1) is 5% to 50% by mass, the epoxy resin (a1) and the ring The total amount of the oxygen resin (a2) is 55% by mass to 100% by mass. In the formula, X is a cycloalkylene group having 5 to 8 ring members having an alkyl group, an aryl group, or an aralkyl group as a substituent.

Description

Epoxy resin composition containing oxazolidinone ring, its production method, curable resin composition, and cured product

The present invention relates to an epoxy resin composition containing an oxazolidinone ring, a method for producing an epoxy resin composition, and a method for producing an epoxy resin composition containing an oxazolidinone ring that provides a cured product excellent in low dielectric properties, high heat resistance, and high adhesiveness. A curable resin composition in which an oxygen resin composition is an essential component, a cured product obtained from the curable resin composition, a prepreg, and a laminate.

Epoxy resin has excellent adhesion, flexibility, heat resistance, chemical resistance, insulation, and hardening reactivity, so it is used in coatings, civil engineering bonding, casting, electrical and electronic materials, and film materials. Especially in the use of printed wiring boards as one of electrical and electronic materials, epoxy resins are widely used by imparting flame retardancy.

As one of the applications of printed wiring boards, portable devices or infrastructure devices such as base stations connecting them have been required to be highly functional as the amount of information has increased dramatically in recent years. In portable devices, high multilayers or fine wiring are made for the purpose of miniaturization. In order to make the substrate thinner, materials with a lower dielectric constant are required. Due to the fine wiring, the bonding surface is reduced, so bonding is required. Materials with higher connectivity. In the base station facing substrate, in order to suppress the attenuation of high-frequency signals, materials with lower dielectric loss tangent are required.

Although the characteristics of low dielectric constant, low dielectric loss tangent, and high adhesion are derived from the structure of epoxy resin as the matrix resin of the printed wiring board, a new epoxy resin or its modification technology is required to a large extent.

Regarding the low dielectric constant of epoxy resin, Patent Document 1 discloses 4,4'-[1,3-phenylenebis(1-methylethylene)]bis[2,6-dimethyl ] Diglycidyl etherate of phenol. In addition, Patent Document 2 discloses an epoxy resin obtained by reacting an epoxy resin having an alcoholic hydroxyl equivalent of 1000 g/eq. or more (1.0 meq/g or less) with an isocyanate compound having two or more isocyanate groups in the molecule. It is also disclosed that the epoxy resin polymerized by the oxazolidinone ring has a low dielectric constant, a low dielectric loss tangent, and a high glass transition temperature.

The epoxy resin containing an oxazolidone ring obtained by reacting an epoxy resin with an isocyanate is also disclosed in Patent Document 3. As a raw material epoxy resin, there are the following examples: Compounds obtained by glycidylation, compounds obtained by glycidylation of tris(glycidyloxyphenyl) alkanes or aminophenols, etc., or novolacs such as phenol novolacs, etc. The compound obtained by radicalization.

Regarding the low dielectric constant of epoxy resins, Patent Document 4 discloses as a raw material epoxy resin that glycidylating dihydric phenols obtained by reacting cycloaliphatic ketones with phenols is disclosed. A compound and an oxazolidinone ring-containing epoxy resin obtained by reacting with an isocyanate compound having two or more isocyanate groups in the molecule.

Regarding the high heat resistance of epoxy resins, Patent Document 5 discloses as a raw material epoxy resin that obtained by reacting a tetramethylbiphenol type epoxy resin with an isocyanate compound having two or more isocyanate groups in the molecule Epoxy resin.

However, none of the epoxy resins disclosed in any of the documents fully meets the requirements for dielectric properties based on high functionality in recent years, and the flame retardancy and adhesiveness are insufficient. [Prior Art Literature]

[Patent Document] [Patent Document 1] Japanese Patent Laid-Open No. 5-293929 [Patent Document 2] Japanese Patent Laid-Open No. 9-278867 [Patent Document 3] Japanese Patent Laid-Open No. 5-43655 [Patent Document 4 ] Japanese Patent Laid-Open No. 2016-169362 [Patent Document 5] Japanese Patent Laid-Open No. 2016-69563

[Problems to be Solved by the Invention] Therefore, the problem to be solved by the present invention is to provide excellent properties with low dielectric properties, high heat resistance, and high adhesiveness, and are useful in applications such as lamination, molding, casting, and bonding. The epoxy resin composition, the curable resin composition containing the epoxy resin composition as an essential component, and the cured product thereof. [Technical means to solve the problem]

In order to solve the above-mentioned problems, the inventors conducted diligent research on materials with low dielectric constant and low dielectric loss tangent. As a result, they found that a mixture of epoxy resins containing two specific epoxy resins as essential components and an isocyanate compound The epoxy resin composition containing the oxazolidinone ring obtained by the reaction can simultaneously achieve low dielectric constant, low dielectric loss tangent, and high flame retardancy that are not available at the present, and furthermore, the adhesion is also good, thus completing the present invention .

That is, the present invention is an epoxy resin composition containing an oxazolidone ring, which is an epoxy resin composition containing an oxazolidone ring obtained from an epoxy resin (a) and an isocyanate compound (b), and It is characterized in that the epoxy resin (a) is a mixture of an epoxy resin (a1) represented by the following formula (1) and an epoxy resin (a2) represented by the following formula (2) as essential components And the epoxy resin (a1) is 5% by mass to 50% by mass, and the total amount of the epoxy resin (a1) and the epoxy resin (a2) is 55% by mass to 100% by mass.

式中，X為具有至少一個選自由碳數1～4的烷基、碳數6～10的芳基及碳數7～11的芳烷基所組成的群組中的取代基的、環員數5～8的伸環烷基。R¹ 及R² 分別獨立地為碳數1～8的烷基、碳數5～8的環烷基、碳數1～4的烯基、碳數6～10的芳基或碳數7～10的芳烷基，k1及k2分別獨立地為0～4的整數。G為縮水甘油基。m及n表示重複數，平均值為0～2。[化1]

In the formula, X is a ring member having at least one substituent selected from the group consisting of an alkyl group having 1 to 4 carbons, an aryl group having 6 to 10 carbons, and an aralkyl group having 7 to 11 carbons. A cycloalkylene group of 5-8. R ¹ and R ² are each independently an alkyl group having 1 to 8 carbons, a cycloalkyl group having 5 to 8 carbons, an alkenyl group having 1 to 4 carbons, an aryl group having 6 to 10 carbons, or a carbon number of 7 to In the aralkyl group of 10, k1 and k2 are each independently an integer of 0-4. G is glycidyl. m and n represent the number of repetitions, and the average value is 0-2.

In addition, the present invention is a method for producing an epoxy resin composition containing an oxazolidinone ring, characterized in that, in the presence of a catalyst, the content represented by the formula (1) is made to contain 5% to 50% by mass. The epoxy resin (a1) and the epoxy resin (a) containing the epoxy resin (a1) of 55 to 100% by mass in total and the epoxy resin (a2) represented by the formula (2), Reacts with isocyanate compound (b).

It is desirable that in the epoxy resin composition containing the oxazolidone ring, or the method for producing the same, one or two or more of the following requirements are satisfied.

1) The alcoholic hydroxyl equivalent of the epoxy resin (a) is 1000 g/eq. or more. 2) The isocyanate compound (b) has an average of 1.8 or more isocyanate groups in the molecule. 3) The epoxy equivalent of the epoxy resin composition containing the oxazolidinone ring is 200 g/eq. to 600 g/eq. 4) The softening point of the epoxy resin composition containing the oxazolidinone ring is 50°C to 150°C. 5) The isocyanate group of the isocyanate compound (b) is in the range of 0.02 mol or more and less than 0.5 mol with respect to 1 molar group of the epoxy resin (a).

In addition, the present invention is a curable resin composition characterized in that the epoxy resin composition containing the oxazolidinone ring and a curing agent are essential components.

The active hydrogen group of the hardening agent is preferably 0.2 mol relative to the 1 molar group of all epoxy resins including the oxazolidinone ring-containing epoxy resin composition in the hardening resin composition. Ear ~ 1.5 moles.

Furthermore, the present invention is a cured product obtained by curing the curable resin composition. In addition, the present invention is a prepreg and a laminated board obtained from the curable resin composition.

[Effects of the Invention] The epoxy resin composition of the present invention and the cured product of the curable resin composition containing the same exhibit cured physical properties that maintain adhesive force and are highly flame-retardant. Furthermore, it has excellent dielectric properties and exhibits good properties in laminates and electronic circuit boards that require low dielectric constant and low dielectric loss tangent.

Hereinafter, an embodiment of the present invention will be described in detail. The epoxy resin composition containing an oxazolidinone ring of the present invention is obtained by reacting an epoxy resin (a) with an isocyanate compound (b). Here, the epoxy resin (a) is a mixture containing the epoxy resin (a1) represented by the formula (1) and the epoxy resin (a2) represented by the formula (2) as essential components.

The epoxy resin composition containing the oxazolidone ring contains epoxy resin (a1) and epoxy resin (a2) containing the oxazolidone ring obtained by reacting the epoxy resin (a1) alone with the isocyanate compound (b) The epoxy resin (A2) containing the oxazolidone ring, which is obtained by reacting with the isocyanate compound (b) alone, and the epoxy resin (a1) and the epoxy resin (a2) are both reacted with the isocyanate compound (b) The epoxy resin (A12) containing the oxazolidinone ring further includes unreacted epoxy resin (a1) and epoxy resin (a2).

In addition, epoxy resin (a) may contain epoxy resin (a3) other than epoxy resin (a1) and epoxy resin (a2). In the above case, it further includes epoxy resin (a3) containing oxazolidone ring-containing epoxy resin (A3), epoxy resin (a1) and epoxy resin (a3) obtained by reacting epoxy resin (a3) alone with isocyanate compound (b) ) Both epoxy resin (A13) containing oxazolidone ring, epoxy resin (a2) and epoxy resin (a3) obtained by reacting both with isocyanate compound (b) react with isocyanate compound (b) The obtained epoxy resin (A23) and epoxy resin (a1) containing oxazolidinone ring react with epoxy resin (a2) and epoxy resin (a3) isocyanate compound (b) containing oxazolidine Ketone ring epoxy resin (A123), and unreacted epoxy resin (a3). Furthermore, the epoxy resin (a3) may contain two or more other epoxy resins. In this case, as described above, the epoxy resin composition containing the oxazolidinone ring contains the oxazolidinone The types of cyclic epoxy resins and unreacted epoxy resins have increased, and the epoxy resins in the epoxy resin (a) are desirably two or three.

In addition, the epoxy resin composition containing the oxazolidone ring also contains an epoxy resin having a urethane structure as a by-product.

As an epoxy resin composition containing an oxazolidinone ring, each epoxy resin (for example, the above A1, A2, A12, a1, a2, A3, A13, A23, A123, a3, etc.) is isolated or concentrated The method is not particularly specific to the method of the present invention, and since each has a molecular weight distribution, it is difficult to perform isolation or concentration by the existing isolation method. In addition, the epoxy resin containing the oxazolidinone ring is similar in structure, so it is difficult to determine the content ratio by analysis by nuclear magnetic resonance (NMR) or infrared spectrophotometer. In the present invention, a specific effect is found in these mixtures, so it is not expressed as "oxazolidone ring-containing epoxy resin" but as "oxazolidone ring-containing epoxy resin composition" . The physical properties of the epoxy resin composition containing an oxazolidinone ring of the present invention can be measured by the same operation as a normal epoxy resin. Therefore, the epoxy resin composition containing the oxazolidinone ring of the present invention does not need to separate each epoxy resin from the reactant, and a part of the epoxy resin may be removed as needed.

The epoxy equivalent (g/eq.) of the epoxy resin composition containing an oxazolidinone ring is preferably 200 to 600, more preferably 215 to 550, and still more preferably 220 to 500. If the epoxy equivalent is low, in addition to the fear of shortening the molecular length and deterioration of adhesion, there are also concerns that the content of the oxazolidinone ring will decrease, and the concentration of hydroxyl groups in the cured product will increase, so the dielectric constant Becomes high. If the epoxy equivalent is high, there is a concern that the molecular length becomes longer than necessary, and adverse effects such as deterioration in solvent solubility or increase in resin viscosity may increase. In addition, there is a concern that the crosslinking density of the cured product becomes low, and therefore, the elastic modulus decreases at the temperature of reflow soldering, which becomes a major problem in use.

In addition, when the softening point is used in a prepreg or a film material, it is preferably 50°C to 150°C, more preferably 55°C to 135°C, and still more preferably 60°C to 120°C. In this case, there is no concern that the softening point is too low, so the lower limit does not need to be paid special attention. If the softening point is high, there is a concern that the viscosity of the resin will increase, the impregnation in the prepreg will deteriorate, or the solubility of the solvent will deteriorate, or the solvent will remain in the resin without being volatilized when it is heated and dried. Voids and the like are generated when the laminate is formed, which becomes a major problem in use.

The epoxy resin (a) used to obtain the epoxy resin composition containing the oxazolidinone ring of the present invention contains the epoxy resin (a1) and the epoxy resin (a2) as essential components, and the epoxy resin ( The sum of a1) and epoxy resin (a2) is 55 mass% to 100 mass% in epoxy resin (a), and epoxy resin (a1) is 5 mass% to 50 mass% in epoxy resin (a) , May contain less than 45% by mass of epoxy resin (a1) and epoxy resin (a3) other than epoxy resin (a2).

The epoxy equivalent of the epoxy resin (a) is preferably 100 to 500, and more preferably 150 to 300. The epoxy equivalent is measured after mixing all epoxy resins including the epoxy resin (a1) and the epoxy resin (a2). In addition, when the epoxy equivalent of the epoxy resin used is known, it can also be calculated|required by calculation.

Since the alcoholic hydroxyl group of the epoxy resin (a) reacts with isocyanate to form a urethane bond, there is a concern that the heat resistance (glass transition point) of the cured product may be lowered. In addition, the concentration of the hydroxyl group in the cured product increases, so there is a concern that the dielectric constant of the cured product becomes higher. Therefore, the alcoholic hydroxyl equivalent (g/eq.) in the epoxy resin (a) is preferably 1000 or more, more preferably 3000 or more, and still more preferably 5000 or more. The alcoholic hydroxyl equivalent is measured after mixing all epoxy resins including the epoxy resin (a1) and the epoxy resin (a2). Furthermore, the larger the alcoholic hydroxyl group equivalent, the smaller the alcoholic hydroxyl group. For example, when m in the formula (1) and n in the formula (2) are 0, the alcoholic hydroxyl group disappears, and the alcoholic hydroxyl group equivalent theoretically becomes infinite, so there is no need to specify the upper limit.

The alcoholic hydroxyl group of the epoxy resin (a) is an alcoholic hydroxyl group generated by the reaction of a phenol compound and epihalohydrin. When the epihalohydrin is epichlorohydrin, these alcoholic hydroxyl groups are derived from 2-chloro-3-hydroxypropyl alcoholic hydroxyl groups (α ), derived from the alcoholic hydroxyl group (β) of 1-chloromethyl-2-hydroxyethyl produced by the addition of a phenol compound to the β position of epichlorohydrin, by adding a phenol compound to the epoxy resin The secondary alcoholic hydroxyl group (γ) produced, and the α-glycol (δ) produced by the hydrolysis of the epoxy group of the epoxy resin. The alcoholic hydroxyl group in the present invention refers to all of (α), (β), (γ) and (δ). Therefore, the alcoholic hydroxyl equivalent is measured as (α), (β), (γ) and (δ). ) All.

In the formula (1), X represents a substituted cycloalkylene group having 5 to 8 ring members. The substituent is an alkyl group having 1 to 4 carbons, an aryl group having 6 to 10 carbons, or an aralkyl group having 7 to 11 carbons, and has at least one of these. The number of substituents may be one or two or more. The cycloalkane ring constituting the cycloalkylene having 5 to 8 ring members is any one of a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, or a cyclooctane ring, preferably a cyclopentane ring Or cyclohexane ring.

Regarding the substituent, for example, examples of the alkyl group having 1 to 4 carbon atoms include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, second butyl, and tertiary butyl. For example, examples of aryl groups having 6 to 10 carbons or aralkyl groups having 7 to 11 carbons include phenyl, benzyl, tolyl, o-xylyl, etc., but are not limited to these, and there are multiple In the case of, they may be the same or different. From the viewpoint of availability and adhesiveness in a laminate, the preferred substituent is a methyl group or a phenyl group.

Furthermore, the cycloalkylene group is preferably a 1,1-cycloalkylene group, and the purpose of the substituent is to use the benzene ring bonded to the 1-position carbon of the cycloalkylene group or the steric interaction between the substituents. The repulsive effect of the cycloalkane ring restricts the mobility of the cycloalkane ring, so that the dielectric properties are improved, and the heat resistance is also improved. If the substitution position is a position that can restrict mobility, it can be bonded to any position, and it is preferably bonded to a carbon atom close to the 1-position of the cycloalkylene group. The preferred position of the substituent is the carbon atom at the 2-position or 5-position in the cyclopentane ring. In the cyclohexane ring, it is a carbon atom at the 2-position, 3-position, 5-position or 6-position, and more preferably a carbon atom at the 2-position or 6-position. In the cycloheptane ring, it is a carbon atom at the 2-position, 3-position, 6-position or 7-position, and more preferably a carbon atom at the 2-position or 7-position. In the cyclooctane ring, it is a carbon atom at position 2, 3-, 4-, 6-, 7-, or 8-position, more preferably 2-, 3-, 7-, or 8-position, and even more preferably 2. Carbon atom at position or 8 position.

In addition, the number of substituents requires at least one for the above-mentioned reasons, and from the viewpoint of heat resistance at the time of making a cured product, it is preferably three or more, and more preferably three.

In formula (1), the -O- group (ether bond) is preferably the ortho position or the para position with respect to the carbon atom to which X is bonded, and more preferably the para position.

In formula (1), R ¹ each independently represents an alkyl group having 1 to 8 carbons, a cycloalkyl group having 5 to 8 carbons, an alkenyl group having 1 to 4 carbons, an aryl group having 6 to 10 carbons, or An aralkyl group having 7 to 10 carbon atoms. For example, examples of the alkyl group having 1 to 8 carbons include methyl, ethyl, propyl, isopropyl, n-butyl, tertiary butyl, hexyl, etc., as the cycloalkyl group having 5 to 8 carbons, Examples include cyclohexyl, etc., as the alkenyl group having 1 to 4 carbons, 1-propenyl or 2-propenyl, etc., as the aryl group having 6 to 10 carbons or the aralkyl group having 7 to 10 carbons, A phenyl group, a benzyl group, a phenethyl group, a 1-phenylethyl group, a naphthyl group, etc. are mentioned, but it is not limited to these, and each may be the same or different. From the viewpoint of availability and physical properties such as heat resistance when used as a cured product, preferred R ¹ is a 1-phenylethyl group or a methyl group. In addition, ^{the substitution position of R 1} is preferably an ortho position or a meta position with respect to the carbon atom to which X is bonded, and more preferably an ortho position. In addition, k1 is each independently 0, 1, 2, 3, or 4, preferably 0, 1, or 2.

In formula (1), m is the number of repetitions, and its average value (number average) is 0 to 2, 0 to 1 is a preferred range, 0 to 0.5 is a more preferred range, and 0 to 0.3 is a still more preferred range. Moreover, the number of repetitions (integer) can usually be in the range of an integer of 0-2. It may be a single compound having a repeating number of any integer from 0 to 2, or it may be a mixture of a plurality of integers from 0 to 2 as m. In the epoxidation of general polyhydric hydroxyl resins using epichlorohydrin and the like, they are obtained as a mixture, and therefore have the advantage that they can be used as they are if it is a mixture.

In the formula (2), R ^{2 , k2 and n have the same meanings as R 1} , k1 and m in the formula (1), and can be changed independently of each other. The substitution position of R ² is preferably the ortho position or the meta position with respect to the carbon atom of the biphenyl bond, and more preferably the ortho position. In addition, the -O- group is preferably the ortho position or the para position with respect to the carbon atom of the biphenyl bond, and more preferably the para position.

The epoxy resin (a1) can be obtained by a known method as follows: a method of reacting a cycloalkylene-containing phenol compound represented by the following formula (3) with epihalohydrin in the presence of a base such as sodium hydroxide , Or the allyl etherification of the cycloalkylene-containing phenol compound represented by the formula (3) by the allyl etherate, followed by oxidation of the allyl group with an oxidizing agent such as peroxide to epoxidize the allyl group Wait.

式中，R¹ 、k1及X分別與式（1）的R¹ 、k1及X為相同含義。[化2]

Wherein, R ^1, k1 and X, respectively R & lt formula (1) is ^1, k1 and X have the same meaning.

The epoxy equivalent of the epoxy resin (a1) is preferably 100 to 500, and more preferably 150 to 300. In addition, the alcoholic hydroxyl equivalent is preferably 1,000 or more, more preferably 2,000 or more, and still more preferably 5,000 or more.

The phenol compound represented by the formula (3) can be obtained by reacting corresponding cyclic aliphatic ketones and phenols. Specifically, the cycloalkylene-containing phenol compounds shown below may be mentioned, but they are not limited to these.

[化3]

These exemplified cycloalkylene-containing phenol compounds can be produced, for example, by the method disclosed in Japanese Patent Laid-Open No. 4-282334 or Japanese Patent Laid-Open No. 2015-51935, and are also available as commercially available products. Examples include: BisP-TMC, BisOC-TMC, BisP-MZ, BisP-3MZ, BisP-IPZ, BisCR-IPZ, Bis26X-IPZ, BisOCP-IPZ, BisP-nBZ, BisOEP-2HBP (the above are product names, Honshu Chemical Industry Manufacturing) and so on.

As the epoxy resin (a1), for example, 4,4'-(2-methylcyclohexylidene)diphenol glycidyl ether, 4,4'-(3-methylcyclohexylidene)diphenol glycidyl Ether, 4,4'-(4-methylcyclohexylene) diphenol glycidyl ether, 4,4'-(3,3,5-trimethylcyclohexylene) diphenol glycidyl ether, 4,4 '-(3,3,5-trimethylcyclohexylene)-bis-phenylphenol glycidyl ether, 4,4'-(3,3,5-trimethylcyclohexylene)-bis-phenyl Phenol glycidyl ether, 4,4'-(3,3,5-trimethylcyclohexylene)-bis-dimethylphenol glycidyl ether, 4,4'-(3,3,5-trimethyl Cyclohexylidene)-bis-tert-butylphenol glycidyl ether, etc., but it is not limited to these, and these epoxy resins may be used alone, or two or more of them may be used in combination.

As the epoxy resin (a1), in terms of the ease of obtaining and the good physical properties of the cured product, a suitable combination of 4,4'-(3,3,5-trimethylcyclohexylidene) diphenol and table The epoxy resin represented by the following formula (4) obtained by halohydrin.

式中，m與式（1）的m為相同含義。[化4]

In the formula, m has the same meaning as m in formula (1).

The epoxy resin (a2) can be obtained by a known method: a method of reacting a biphenol compound represented by the following formula (5) with epihalohydrin in the presence of a base such as sodium hydroxide, or using allyl After allyl etherification of the biphenol compound represented by the formula (5), a method of epoxidizing the allyl group by oxidizing the allyl group with an oxidizing agent such as peroxide.

式中，R² 及k2分別與式（2）的R² 及k2為相同含義。[化5]

In the formula, R ^{2 and k2 have the same meaning as R 2} and k2 in the formula (2), respectively.

The epoxy equivalent of the epoxy resin (a2) is preferably 100 to 500, and more preferably 150 to 300. In addition, the alcoholic hydroxyl equivalent is preferably 1,000 or more, more preferably 2,000 or more, and still more preferably 5,000 or more.

As the biphenol compound represented by formula (5), for example, 4,4'-biphenol, 2,4'-biphenol, 2,2'-biphenol, 3,3'-biphenol, 2, 2'-dimethyl-4,4'-biphenol, 3,3'-dimethyl-4,4'-biphenol, 2,2',6,6'-tetramethyl-4,4' -Biphenol, 2,2',5,5'-tetramethyl-4,4'-biphenol, 2,2',3,3',6,6'-hexamethyl-4,4'- Biphenol, 2,2'-diethyl-4,4'-biphenol, 3,3'-diethyl-4,4'-biphenol, 2,2',6,6'-tetraethyl -4,4'-biphenol, 2,2',5,5'-tetraethyl-4,4'-biphenol, 2,2'-diallyl-4,4'-biphenol, 3 ,3'-diallyl-4,4'-biphenol, 2,2',6,6'-tetraallyl-4,4'-biphenol, 2,2',5,5'- Tetraallyl-4,4'-biphenol, 2,2',5,5'-tetra-tert-butyl-4,4'-biphenol, 2,2',6,6'-tetra- Tertiary butyl-4,4'-biphenol, 2,2'-cyclohexyl-4,4'-biphenol, 2,2'-diphenyl-4,4'-biphenol, 2,2' ,3,3',5,5'-hexamethylbiphenyl-4,4'-diol etc., but it is not limited to these. In addition, these biphenol compounds may be used alone, or two or more of them may be used in combination. In particular, when 4,4'-biphenol is used, it is preferably used in combination with another biphenol compound.

These exemplified phenol compounds are also available as commercially available products, for example: BP, 26X-BP, TTB-BP, DM-BP, PCR-BP, TMP-BP, 24B-BP (the above are product names, Honshu Chemical industry manufacturing) etc.

As the epoxy resin (a2), for example, 4,4'-bis(glycidyloxy)biphenyl, 2,2'-bis(glycidyloxy)biphenyl, 3,3',5 ,5'-Tetramethyl-4,4'-bis(glycidyloxy)biphenyl, 3,3'-dimethyl-4,4'-bis(glycidyloxy)biphenyl, 3 ,3',5,5'-Tetra-tert-butyl-4,4'-bis(glycidyloxy)biphenyl, 3,3'-cyclohexyl-4,4'-bis(glycidyl (Oxy)biphenyl, 3,3'-diphenyl-4,4'-bis(glycidyloxy)biphenyl, etc., but not limited to these, these epoxy resins can be used alone or in combination Two or more.

As the epoxy resin (a2), in terms of the ease of obtaining and the good physical properties of the cured product, it is suitable to be composed of 2,2',6,6'-tetramethyl-4,4'-biphenol and table The epoxy resin represented by the following formula (6) obtained from halohydrins.

式中，n與式（2）的n為相同含義。[化6]

In the formula, n has the same meaning as n in formula (2).

The blending ratio of epoxy resin (a1) and epoxy resin (a2) is 1/9-9/1 in terms of mass ratio, epoxy resin (a1) must contain 5 mass%-50% in epoxy resin (a) quality%. If the epoxy resin (a1) exceeds 50% by mass, the heat resistance or adhesiveness may not be sufficiently exhibited, and the flame retardancy may be insufficient in a flame-retardant formulation using a phosphorus-based flame retardant. The usage amount of the epoxy resin (a2) varies depending on the usage amount of the epoxy resin (a1), and the total usage amount of the epoxy resin (a1) and the epoxy resin (a2) must be 55% by mass or more. That is, it is understood that: Regarding the amount of epoxy resin (a2) used, when the epoxy resin (a1) is 5% by mass, it is used in the range of 50% to 95% by mass, and the epoxy resin (a1) When) is 50% by mass, use within the range of 5% by mass to 50% by mass. If the total is less than 55% by mass, the dielectric properties may be insufficient. The blending ratio (a1/a2) of epoxy resin (a1) and epoxy resin (a2) in epoxy resin (a) is based on mass %, preferably 5-50/95-50, more preferably 25- 40/75 to 55, more preferably 40 to 45/60 to 55.

As the epoxy resin (a), as long as the effect of the present invention is not impaired, 45% by mass or less of the epoxy resin (a1) and epoxy resin (a3) other than the epoxy resin (a2) may be used in combination. In this case, the blending ratio of the epoxy resin (a1) and the epoxy resin (a2) is based on a mass ratio, and is preferably 4/6 to 5/5. The purpose of using the epoxy resin (a3) in combination is, for example, to impart other characteristics such as further improvement of solvent solubility. Therefore, the amount of the epoxy resin (a3) used is preferably as small as possible, more preferably 35% by mass or less, still more preferably 20% by mass or less, and particularly preferably 10% by mass or less.

The epoxy equivalent of the epoxy resin (a3) is preferably 100 to 500, and more preferably 170 to 300. In addition, the alcoholic hydroxyl equivalent is preferably 1,000 or more, more preferably 2,000 or more, and still more preferably 5,000 or more.

Examples of epoxy resins (a3) that can be used in combination include: bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetramethyl bisphenol F type epoxy resin, bisphenol fluorene type epoxy resin, and naphthalene Diphenol type epoxy resin, bisphenol S type epoxy resin, disulfide type epoxy resin, hydroquinone type epoxy resin, resorcinol type epoxy resin, phenol novolak type epoxy resin, methyl Phenolic novolak type epoxy resin, alkyl novolak type epoxy resin, styrenated phenol novolak type epoxy resin, naphthol novolak type epoxy resin, β-naphthol aralkyl type epoxy resin, two Naphthol aralkyl type epoxy resin, α-naphthol aralkyl type epoxy resin, biphenyl aralkyl phenol type epoxy resin and other polyglycidyl ether compounds, diaminodiphenylmethane tetraglycidyl ether , N,N,N',N'-tetraglycidyl-1,3-benzenedi(methylamine) and other polyglycidyl amine compounds, dimer acid type epoxy resins and other polyglycidyl ester compounds, fats Alicyclic epoxy compounds such as tricyclic epoxy resins are not limited to these, and these epoxy resins may be used alone or in combination of two or more kinds.

Among the epoxy resins (a3) that can be used in combination, for the purpose of further reducing the dielectric constant, epoxy resins containing aliphatic substituents or bisphenol AF type epoxy resins having a fluorine atom in the molecule are preferable in order to increase heat resistance. Polyfunctional phenol novolac type epoxy resins and cresol novolac type epoxy resins are preferred for the purpose of further improving performance, and bisphenol S type epoxy resins or bisphenol novolak type epoxy resins are preferred for the purpose of increasing the refractive index and further improving heat resistance. Bisphenol fluorene type epoxy resin is preferably diphenyl ether type epoxy resin or benzophenone type epoxy resin for the purpose of improving thermal conductivity, and bisphenol A type epoxy resin is respectively preferable for the purpose of reducing viscosity Or bisphenol F type epoxy resin, but it is not limited to these.

When manufacturing the epoxy resin composition containing an oxazolidinone ring of this invention, the isocyanate compound (b) is used together with the epoxy resin (a). The reaction of the epoxy resin (a) and the isocyanate compound (b) can be used to obtain a desired epoxy resin composition containing an oxazolidone ring. The isocyanate compound (b) may be an isocyanate compound having an average of 1.8 or more isocyanate groups (-N=C=O) in the molecule, and a known and commonly used isocyanate compound can be used. The monofunctional isocyanate compound may be contained in a small amount, but it serves as a terminal group and is therefore effective for the purpose of lowering the degree of polymerization, but the degree of polymerization does not increase, so it is not preferable for the purpose of the present invention.

Specifically, examples include: 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 3,5-toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenyl Methane diisocyanate, 4,4'-diphenylmethane diisocyanate, m-xylene diisocyanate, p-xylene diisocyanate, tetramethyl xylene diisocyanate, 1,4-naphthalenediyl diisocyanate, 1,5 -Naphthalenediyl diisocyanate, 2,6-naphthalenediyl diisocyanate, 2,7-naphthalenediyl diisocyanate, naphthalene-1,4-diyl bis(methylene) diisocyanate, naphthalene-1,5- Diyl bis(methylene) diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, biphenyl-4,4'-diisocyanate, 3,3'-dimethyl bisphenyl-4,4'-di Isocyanate, 2,3'-dimethoxybisphenyl-4,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, 3,3'-dimethoxydiphenylmethane- 4,4'-diisocyanate, 4,4'-dimethoxydiphenylmethane-3,3'-diisocyanate, diphenyl sulfite-4,4'-diisocyanate, diphenyl sulfide-4 ,4'-Diisocyanate, bicyclo[2.2.1]heptane-2,5-diylbismethylene diisocyanate, bicyclo[2.2.1]heptane-2,6-diylbismethylene diisocyanate , Isophorone diisocyanate, 4,4'-methylene biscyclohexyl diisocyanate, lysine diisocyanate, 1,1-bis(isocyanate methyl)cyclohexane, 1,2-bis(isocyanate methyl) )Cyclohexane, 1,3-bis(isocyanatemethyl)cyclohexane, 1,4-bis(isocyanatemethyl)cyclohexane, 1,3-cyclohexylene diisocyanate, 1,4-cyclohexylene Diisocyanate, 4-methyl-1,3-cyclohexylene diisocyanate, 2-methyl-1,3-cyclohexylene diisocyanate, 1-methylbenzene-2,4-diisocyanate, 1-methyl Benzene-2,5-diisocyanate, 1-methylbenzene-2,6-diisocyanate, 1-methylbenzene-3,5-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethyl Hexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, methane diisocyanate, ethane-1,2-diisocyanate, propane-1,3-diisocyanate, butane- 1,1-diisocyanate, butane-1,2-diisocyanate, butane-1,4-diisocyanate, 2-butene-1,4-diisocyanate, 2-methylbutene-1,4- Diisocyanate, 2-methylbutane-1,4-diisocyanate, pentane-1,5-diisocyanate, 2,2-dimethylpentane-1,5-diisocyanate, hexane-1,6 -Diisocyanate, heptane-1,7-diisocyanate, octane-1,8-diisocyanate, nonane-1,9-diisocyanate, decane-1,10-diisocyanate, dimethylsilane diisocyanate , Difunctional isocyanate compounds such as diphenylsilane diisocyanate, or triphenylmethane triisocyanate Esters, 1,3,6-hexamethylene triisocyanate, 1,8-diisocyanato-4-isocyanate methyl octane, bicycloheptane triisocyanate, tris(isocyanate phenyl) phosphorothioate, Lysine triisocyanate, undecane triisocyanate, tris(4-phenylisocyanate phosphorothioate)-3,3',4,4'-diphenylmethane tetraisocyanate, polymethylene polyphenyl Multifunctional isocyanate compounds such as isocyanates, or multimers such as dimers or trimers of the isocyanate compounds, or blocked isocyanates masked with blocking agents such as alcohols or phenols, or diurethanes Compounds and the like are not limited to these, and these isocyanate compounds may be used alone, or two or more of them may be used in combination.

Among these isocyanate compounds, a bifunctional isocyanate compound or a trifunctional isocyanate compound is preferable, and a bifunctional isocyanate compound is more preferable. If the number of functional groups of the isocyanate compound is large, the storage stability may decrease, and if the number of functional groups of the isocyanate compound is small, the heat resistance or dielectric properties may not be improved.

Particularly preferred isocyanate compound (b) is selected from 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 3,5-toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4 '-Diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, m-xylene diisocyanate, p-xylene diisocyanate, tetramethylxylene diisocyanate, 1,4-naphthalenediyl diisocyanate , 1,5-naphthalenediyl diisocyanate, 2,6-naphthalenediyl diisocyanate, 2,7-naphthalenediyl diisocyanate, 3,3'-dimethyl bisphenyl-4,4'-diisocyanate , M-phenylene diisocyanate, p-phenylene diisocyanate, cyclohexane-1,4-diyl diisocyanate, cyclohexane-1,3-diyl bismethylene diisocyanate, cyclohexane-1,4-di Bismethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 4,4 '-Methylenebiscyclohexyl diisocyanate, bicyclo[2.2.1]heptane-2,5-diylbismethylene diisocyanate, bicyclo[2.2.1]heptane-2,6-diylbismethylene One or more of the group consisting of diisocyanate and isophorone diisocyanate.

The reaction of the epoxy resin (a) and the isocyanate compound (b) can be performed by a known method. The specific reaction methods are: 1) Melt the epoxy resin (a), use dry gas flushing or reduce the pressure in the system to remove the water in the epoxy resin, and then add the isocyanate compound (b) and catalyst The method of reaction; or 2) Pre-mix the epoxy resin (a) and the catalyst, use dry gas flushing or reduce the pressure in the system to remove the water in the epoxy resin, and then add the isocyanate compound (b) ) And the method of reaction. The amount of moisture in the system at this time is preferably 0.5% by mass or less, more preferably 0.1% by mass or less, and still more preferably 0.05% by mass or less. In addition, in any method, when the resin has a high viscosity and is difficult to stir, if necessary, a non-reactive solvent can also be used.

Regarding the usage amount of the epoxy resin (a) and the isocyanate compound (b), it is preferable that the isocyanate group of the isocyanate compound (b) be 0.02 mol or more and less than 1 mole of the epoxy resin (a) The range of 0.5 mol is more preferably the range of 0.1 mol or more and 0.45 mol or less, still more preferably the range of 0.15 mol or more and 0.4 mol or less, and particularly preferably the range of 0.2 mol or more and 0.35 mol or less . If the ratio of isocyanate groups is low, the amount of oxazolidone rings produced decreases, and there is a concern that the effect of improving the dielectric properties and heat resistance of the cured product cannot be obtained. In addition, if the ratio of isocyanate groups is large, not only the residual amount of epoxy groups decreases, but also the thickening becomes violent during the reaction, and the reaction becomes difficult. In addition, even if it is obtained, the solvent solubility or the impregnation property in the glass cloth deteriorates, and it is difficult to use it for laminated board applications.

The reaction mechanism for forming the oxazolidinone ring is as described in Patent Document 4. The epoxy resin (a) and the isocyanate compound (b) react with the epoxy group of the epoxy resin (a) and the isocyanate group of the isocyanate compound (b) by adding a catalyst to form an oxazolidinone ring. In addition, when the epoxy resin (a) contains an alcoholic hydroxyl group, the isocyanate group of the isocyanate compound (b) and the alcoholic hydroxyl group undergo an addition reaction to form a urethane bond. The addition temperature of the catalyst is preferably room temperature to 150°C, more preferably room temperature to 100°C.

Usable catalysts include: lithium compounds, complex salts of boron trifluoride, quaternary ammonium salts, tertiary amines, phosphines, phosphonium salts, combinations of triphenyl antimony and iodine, imidazoles These catalysts, alkali metal hydroxides, etc., are not limited to these, and these catalysts may be used alone, or two or more of them may be used in combination. In addition, it can also be divided and used in fractions. Among these catalysts, quaternary ammonium salts, tertiary amines, phosphines, or phosphonium salts are preferred, and tetramethylammonium iodide is more preferred in terms of reaction activity and reaction selectivity. If it is a catalyst with low reaction activity, the reaction time may be longer and the productivity may decrease. If it is a catalyst with low reaction selectivity, there is a concern that the polymerization reaction of epoxy groups may proceed and the target physical properties may not be obtained. .

The amount of the catalyst is not particularly limited. It is preferably 0.0001% to 5% by mass relative to the total mass of the epoxy resin (a) and isocyanate compound (b), more preferably 0.0005% to 1% by mass, and still more preferably 0.001% by mass to 0.5% by mass, particularly preferably 0.002% by mass to 0.2% by mass. If the amount of the catalyst is large, there is a concern that the self-polymerization reaction of the epoxy group proceeds depending on the situation, and therefore the resin viscosity becomes high. In addition, there is a concern that the self-polymerization reaction of isocyanate is promoted and the formation of oxazolidinone ring is suppressed. Furthermore, there is a concern that it may remain as an impurity in the produced resin, and when it is used in various applications, particularly as a material for a laminate or a sealing material, it may cause a decrease in insulation or a decrease in moisture resistance. If the amount of the catalyst is small, there is a concern that the efficiency for obtaining an epoxy resin composition containing an oxazolidinone ring may decrease.

The reaction temperature is preferably 100°C to 250°C, more preferably 100°C to 200°C, and still more preferably 120°C to 160°C. If the reaction temperature is low, there is a concern that the formation of the oxazolidone ring cannot proceed sufficiently, and the isocyanurate ring is formed due to the trimerization reaction of the isocyanate group. In addition, if the reaction temperature is high, there is a concern that local high molecular weight will be caused and the production of insoluble gel components will increase. Therefore, the rate of addition of the isocyanate compound (b) must be adjusted. If the rate of addition of the isocyanate compound (b) is high, there is a concern that cooling is not available for heat generation, and the preferred reaction temperature cannot be maintained. In addition, if the addition rate is slow, there is a concern that productivity is significantly reduced.

The reaction time is preferably 15 minutes to 10 hours after the completion of the addition of the isocyanate compound (b), more preferably 30 minutes to 8 hours, and still more preferably 1 hour to 5 hours. If the reaction time is short, a large amount of isocyanate groups may remain in the product. If the reaction time is long, there is a concern that productivity is significantly reduced.

In addition, when the epoxy resin (a) and the isocyanate compound (b) are reacted, various modifiers can be further used in the epoxy resin composition of the present invention within a range that does not affect the effect. It is easy to adjust the molecular weight (epoxy equivalent) etc. by using a modifier. With respect to 100 parts by mass of the epoxy resin (a), the amount used is preferably 80 parts by mass or less, more preferably 25 parts by mass or less, and still more preferably 10 parts by mass or less.

Usable modifiers include bisphenols such as bisphenol A and bisphenol F, diphenols, monocyclic bifunctional phenols such as resorcinol and hydroquinone, dihydroxy naphthalenes, and novolacs. Various phenols such as resins, heavy oil-modified phenol resins, or polyphenol resins obtained by the condensation reaction of various phenols and various aldehydes, or amine compounds, but are not limited to these. These modifiers can be It can be used alone, or two or more of them can be used in combination. In addition, when these modifiers have an aromatic ring, the aromatic ring may be substituted with a substituent that has no adverse effects such as an alkyl group or an aryl group.

In addition, a non-reactive solvent can also be used as needed. For example, various hydrocarbons such as hexane, heptane, octane, dimethylbutane, cyclohexane, methylcyclohexane, benzene, toluene, xylene, ethylbenzene, etc., or dibutyl ether, Ethers such as dioxane and tetrahydrofuran, or cellosolves such as methyl cellosolve and ethyl cellosolve, or glycol ethers such as ethylene glycol dimethyl ether, etc., but are not particularly limited to these. These solvents It can be used alone, or two or more of them can be used in combination. The amount of these solvents used is preferably 1 part by mass to 900 parts by mass relative to 100 parts by mass of the epoxy resin (a), and more preferably 5 parts by mass to 100 parts by mass.

The reaction product obtained as described above can be obtained as the epoxy resin composition containing the oxazolidone ring of the present invention by removing a part of the solvent or catalyst, or unreacted product or product as needed, or as needed.

Next, the curable resin composition of the present invention will be described. The curable resin composition of the present invention includes the oxazolidone ring-containing epoxy resin composition of the present invention and a curing agent.

The hardener is not particularly limited as long as it can harden the epoxy resin. Phenolic hardeners, acid anhydride hardeners, amine hardeners, hydrazine hardeners, active ester hardeners, phosphorus-containing hardeners, etc. can be used Hardener for epoxy resin. These hardeners may be used alone, or two or more of them may be used in combination. Among these, dicyandiamine, a phenol-based curing agent, or an active ester-based curing agent is preferable, and a phenol-based curing agent or an active ester-based curing agent is more preferable.

The amount of hardener used is preferably such that the active hydrogen group of the hardener is set to 0.2 mol to 1.5 mol relative to 1 mole of all epoxy groups of the epoxy resin composition containing the oxazolidinone ring It is more preferably 0.3 mol to 1.5 mol, still more preferably 0.5 mol to 1.5 mol, particularly preferably 0.8 mol to 1.2 mol. When the active hydrogen group of the hardening agent is not in the above-mentioned range, there is a concern that hardening is incomplete and good hardened physical properties cannot be obtained. For example, in the case of using a phenol-based hardener or an amine-based hardener, an active hydrogen group of approximately equal moles relative to the epoxy group is formulated, and in the case of using an acid anhydride-based hardener, relative to 1 mole of the ring An oxy group is used to prepare an acid anhydride group of 0.5 mol to 1.2 mol, preferably 0.6 mol to 1.0 mol.

The active hydrogen group in the present invention refers to a functional group having an active hydrogen reactive with an epoxy group (including a functional group having a potential active hydrogen that generates active hydrogen due to hydrolysis or the like, or showing equivalent The functional group for curing action), specifically, an acid anhydride group, a carboxyl group, an amino group, or a phenolic hydroxyl group can be mentioned. Furthermore, with regard to the active hydrogen group, 1 mol of carboxyl or phenolic hydroxyl group is calculated as 1 mol, and 1 mol of amine group (NH ₂ ) is calculated as 2 mol. In addition, when the active hydrogen group is not clear, the active hydrogen equivalent can be determined by measurement. For example, by reacting a monoepoxy resin with a known epoxy equivalent such as phenyl glycidyl ether with a hardening agent whose active hydrogen equivalent is unknown, the amount of monoepoxy resin consumed can be measured, and the hardening agent used can be determined. Active hydrogen equivalent.

Specific examples of phenol resin curing agents include bisphenols such as bisphenol A and bisphenol F, or dihydroxybenzenes such as resorcinol, hydroquinone, and di-tertiary butyl hydroquinone. Type, or hydroxynaphthalenes such as dihydroxynaphthalene and trihydroxynaphthalene, or phenols and/or naphthols such as phenol novolak resin, cresol novolak resin, trihydroxyphenylmethane type novolak resin, naphthol novolak resin, etc. Condensates with aldehydes and/or condensing agents, etc.

In this case, phenols include phenol, cresol, xylenol, butylphenol, amylphenol, nonylphenol, butylmethylphenol, trimethylphenol, phenylphenol, and the like. Examples of naphthols include 1-naphthol and 2-naphthol. Aldehydes include: formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, hexanal, benzaldehyde, chloral, bromoaldehyde, glyoxal, malonaldehyde, succinal, glutaraldehyde, adipaldehyde , Pimelic aldehyde, sebacaldehyde, acrolein, crotonaldehyde, salicylaldehyde, o-phthalaldehyde, hydroxybenzaldehyde, etc. Condensing agents include: xylylene glycol, bis(hydroxymethyl)biphenyl, bis(methoxymethyl)biphenyl, bis(ethoxymethyl)biphenyl, bis(chloromethyl)biphenyl Benzene etc.

In addition, a benzoxazine compound that opens a ring during heating to become a phenol compound is also useful as a curing agent. For example, bisphenol F type or bisphenol S type benzoxazine compound etc. are mentioned, but it is not limited to these.

Examples of acid anhydride hardeners include methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, pyromellitic dianhydride, phthalic anhydride, trimellitic anhydride, and methyl nadic Sour etc.

Examples of amine hardeners include diethylenetriamine, triethylenetetramine, metaxylylenediamine, isophorone diamine, diaminodiphenylmethane, diaminodiphenyl sulfide, and diaminodiphenylmethane. Aminodiphenyl ether, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, dicyandiamine, as a dimer acid and other acid and polyamine condensate The polyamide-amine and other amine compounds.

Examples of active ester curing agents include reaction products of polyfunctional phenolic compounds and aromatic carboxylic acids as described in Japanese Patent No. 5152445, and commercially available products include Epiclon HPC-8000-65T (product Name, DIC Co., Ltd.), etc.

Examples of other curing agents include phosphine compounds such as triphenylphosphine, phosphonium salts such as tetraphenylphosphonium bromide, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, Imidazoles such as 2-undecylimidazole and 1-cyanoethyl-2-methylimidazole, imidazole salts as salts of imidazoles and trimellitic acid, isocyanuric acid, boric acid, etc., trimethyl chloride Quaternary ammonium salts such as ammonium chloride, diazabicyclic compounds, salts of diazabicyclic compounds and phenols or phenol novolac resins, complex compounds such as boron trifluoride and amines or ether compounds, Aromatic phosphonium, or enzymatic salt, etc.

A hardening accelerator can be used as needed. Examples of usable hardening accelerators include imidazoles such as 2-methylimidazole, 2-ethylimidazole, and 2-ethyl-4-methylimidazole, 2-(dimethylaminomethyl)phenol , 1,8-diaza-bicyclo(5,4,0)undecene-7 and other tertiary amines, triphenylphosphine, tricyclohexylphosphine, triphenylphosphine triphenylborane and other phosphines , Tin octoate and other metal compounds. With respect to 100 parts by mass of the epoxy resin component in the epoxy resin composition of the present invention, 0.02 parts by mass to 5 parts by mass of the hardening accelerator are used as needed. By using a hardening accelerator, the hardening temperature can be lowered, or the hardening time can be shortened.

Furthermore, if necessary, epoxy resins other than the oxazolidinone ring-containing epoxy resin composition of the present invention may be used within a range that does not impair the physical properties of the curable resin composition. Examples of usable epoxy resins include: bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetramethyl bisphenol F type epoxy resin, hydroquinone type epoxy resin, and bisphenol Fluorene type epoxy resin, bisphenol S type epoxy resin, disulfide type epoxy resin, resorcinol type epoxy resin, biphenyl aralkyl phenol type epoxy resin, naphthalene diphenol type epoxy resin, Phenol novolak type epoxy resin, styrenated phenol novolak type epoxy resin, cresol novolak type epoxy resin, alkyl novolak type epoxy resin, bisphenol novolak type epoxy resin, naphthol novolak type epoxy resin Type epoxy resin, β-naphthol aralkyl type epoxy resin, dinaphthol aralkyl type epoxy resin, α-naphthol aralkyl type epoxy resin, triphenylmethane type epoxy resin, four Hydroxyphenylethane type epoxy resin, dicyclopentadiene type epoxy resin, alkylene glycol type epoxy resin, polyglycidyl ether compound of aliphatic cyclic epoxy resin, or diaminodiphenylmethane Type epoxy resin, m-xylylenediamine type epoxy resin, 1,3-bisaminomethyl cyclohexane type epoxy resin, isocyanurate type epoxy resin, aniline type epoxy resin, hydantoin Polyglycidyl amine compounds such as urea type epoxy resins and aminophenol type epoxy resins, or polyglycidyl ester compounds such as dimer acid type epoxy resins and hexahydrophthalic type epoxy resins, or alicyclics Formula epoxy compound. In addition, urethane-modified epoxy resin [for example, AER4152 (product name, manufactured by Asahi Kasei Electronic Materials Co., Ltd.), etc.], the epoxy resin composition containing an oxazolidinone ring of the present invention may be mentioned. Epoxy resins containing oxazolidinone rings, epoxy modified polybutadiene rubber derivatives [such as PB-3600 (product name, manufactured by Daicel Chemical Industry Co., Ltd.), etc.], CTBN modified epoxy resins [For example, Epotohto YR-102, Epotohto YR-450 (the above are product names, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), etc.], but not limited to these. These rings Oxygen resin may be used alone, or two or more kinds may be used in combination.

In addition, an organic solvent and/or a reactive diluent can be used in the epoxy resin composition and the curable resin composition containing the oxazolidinone ring of the present invention to adjust the viscosity. These organic solvents and/or reactive diluents may be used alone, or two or more of them may be mixed.

Examples of the organic solvent include: amines such as N,N-dimethylformamide, N,N-dimethylacetamide, or dioxane, tetrahydrofuran, ethylene glycol monomethyl ether, and dimethyl acetamide. Diethylene glycol, ethylene glycol diethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether and other ethers, or acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone Other ketones, or methanol, ethanol, 1-methoxy-2-propanol, 2-ethyl-1-hexanol, benzyl alcohol, ethylene glycol, propylene glycol, butyldiglycol, pine oil and other alcohols Class, or ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, cellosolve acetate, ethyl diethylene glycol acetate, propylene glycol monomethyl ether acetate , Carbitol acetate, benzyl alcohol acetate and other acetates, or methyl benzoate, ethyl benzoate and other benzoates, or methyl cellosolve, cellosolve, butyl cellosolve, etc. Cellosolves, or carbitols such as methyl carbitol, carbitol, and butyl carbitol, or aromatic hydrocarbons such as benzene, toluene, and xylene, or subsulfides such as dimethyl sulfoxide , Or alkanes such as hexane and cyclohexane, or acetonitrile, N-methylpyrrolidone, etc. Examples of reactive diluents include monofunctional glycidyl ethers such as allyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and cresyl glycidyl ether. , Or resorcinol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, cyclohexane dimethanol Difunctional glycidyl ethers such as glycidyl ether and propylene glycol diglycidyl ether, or glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, trimethylolethane polyglycidyl ether, pentaerythritol polyglycidyl ether Glycidyl ethers such as polyfunctional glycidyl ethers, glycidyl esters such as glycidyl neodecanoate, and glycidyl amines such as phenyl diglycidyl amine and tolyl diglycidyl amine.

These organic solvents and/or reactive diluents are preferably used in an amount with a non-volatile content of 90% by mass or less, and the appropriate kind or amount of use can be appropriately selected according to the application. For example, in the use of printed wiring boards, polar solvents such as methyl ethyl ketone, acetone, 1-methoxy-2-propanol and the like with a boiling point of 160°C or less are preferred, and the amount used is preferably 40 mass based on non-volatile content. %～80% by mass. In addition, for adhesive film applications, for example, ketones, acetates, carbitols, aromatic hydrocarbons, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. are preferably used. The use amount thereof is preferably 30% by mass to 60% by mass in terms of non-volatile components.

The curable resin composition can be blended with other thermosetting resins and thermoplastic resins within a range that does not impair the characteristics. Examples include: phenol resin, acrylic resin, petroleum resin, indene resin, coumarone-indene resin, phenoxy resin, polyurethane resin, polyester resin, polyamide resin, Polyimide resin, polyimide imide resin, polyetherimide resin, polyphenylene ether resin, modified polyphenylene ether resin, polyether oxide resin, polyimide resin, polyether ether ketone resin, polyphenylene Sulfide resin, polyvinyl formal (polyvinyl formal) resin, etc., but it is not limited to these.

In the curable resin composition, various conventionally known flame retardants can be used for the purpose of improving the flame retardancy of the obtained cured product. Usable flame retardants include, for example, halogen flame retardants, phosphorus flame retardants, nitrogen flame retardants, silicone flame retardants, inorganic flame retardants, and organic metal salt flame retardants. Wait. From the viewpoint of the environment, 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 them may be used in combination.

As the phosphorus-based flame retardant, either an inorganic phosphorus-based compound or an organic phosphorus-based compound can be used. Examples of inorganic phosphorus compounds include ammonium phosphates such as red phosphorus, monoammonium phosphate, diammonium phosphate, triammonium phosphate, and ammonium polyphosphate, and inorganic nitrogen-containing phosphorus compounds such as phosphamide. Examples of organic phosphorus compounds include: aliphatic phosphate esters, phosphate ester compounds, condensed phosphate esters, phosphonic acid compounds, phosphinic acid compounds, phosphine oxide compounds, phosphorous compounds, organic nitrogen-containing phosphorus compounds and other general organic compounds. Phosphorus compounds, or metal salts of phosphinic acid, in addition to these include: 9,10-dihydro-9-oxa-10-phosphinphenanthrene-10-oxide (DOPO), 10-(2,5- Dihydroxyphenyl)-10H-9-oxa-10-phosphinphenanthrene-10-oxide (DOPO-HQ), 10-(2,7-dihydroxynaphthyl)-10H-9-oxa-10- Phosphophenanthrene-10-oxide (DOPO-NQ) and other cyclic organophosphorus compounds, or phosphorus-containing epoxy resins or phosphorus-containing resins as derivatives obtained by reacting these compounds with compounds such as epoxy resins or phenol resins Hardener, etc.

Examples of epoxy resins containing phosphorus include Albert (Epotohto) FX-305, Albert (Epotohto) FX-289B, TX-1320A, Albert (Epotohto) TX-1328 (the above are product names, Nippon Steel & Sumikin Chemical Co., Ltd.), but not limited to these. The epoxy equivalent of the phosphorus-containing epoxy resin may be 200-800, preferably 300-780, and more preferably 400-760. In addition, the phosphorus content of the phosphorus-containing epoxy resin may be 0.5% by mass to 6% by mass, preferably 2% by mass to 5.5% by mass, and more preferably 3% by mass to 5% by mass.

As phosphorus-containing hardeners, in addition to phosphorus-containing phenols such as DOPO-HQ, DOPO-NQ, and diphenylphosphinylhydroquinone, Japanese Patent Publication No. 2008-501063 or Japanese Patent No. 4548547 can be used. In the manufacturing method shown in the No. Bulletin, DOPO, aldehydes, and phenol compounds are reacted to obtain phosphorus-containing phenol compounds. In this case, DOPO is condensed and added to the aromatic ring of the phenol compound via aldehydes to be incorporated into the molecule. In addition, a production method as shown in Japanese Patent Laid-Open No. 2013-185002 can be used to further react with aromatic carboxylic acids to obtain a phosphorus-containing active ester compound from a phosphorus-containing phenol compound having DOPO as a unit structure. . In addition, it is possible to obtain a phosphorus-containing benzoxazine compound having a DOPO unit structure using a production method as shown in Japanese Patent Publication No. WO2008/010429. The phosphorus content of the phosphorus-containing hardener may be 0.5% by mass to 12% by mass, preferably 2% by mass to 11% by mass, and more preferably 4% by mass to 10% by mass.

The blending amount of the flame retardant is appropriately selected according to the kind of phosphorus flame retardant, the components of the curable resin composition, and the degree of desired flame retardancy. For example, the phosphorus content in the organic component (excluding the organic solvent) in the curable resin composition is preferably 0.2% by mass to 6% by mass, more preferably 0.4% by mass to 4% by mass, and still more preferably 0.5% by mass to 3.5. % By mass, particularly preferably 0.6% by mass to 3% by mass. If the phosphorus content is small, it may be difficult to ensure flame retardancy, and if the phosphorus content is too large, there is a concern that it may adversely affect heat resistance. In addition, when a phosphorus-based flame retardant is used, a flame retardant auxiliary such as magnesium hydroxide may be used in combination.

In addition, the epoxy resin containing phosphorus is treated as a compound corresponding to both phosphorus-based flame retardants and epoxy resins, and the curing agent containing phosphorus is treated as a compound corresponding to both phosphorus-based flame retardants and curing agents. And deal with. Therefore, when an epoxy resin containing phosphorus is used, other phosphorus-based flame retardants are sometimes unnecessary. Similarly, when using a hardening agent containing phosphorus, other hardening agents and/or phosphorus-based flame retardants may not be necessary.

A filler may be used in the curable resin composition as needed. Specific examples include: fused silica, crystalline silica, alumina, silicon nitride, aluminum hydroxide, boehmite, magnesium hydroxide, talc, mica, calcium carbonate, calcium silicate, calcium hydroxide, Magnesium carbonate, barium carbonate, barium sulfate, boron nitride, carbon, carbon fiber, glass fiber, alumina fiber, silica alumina fiber, silicon carbide fiber, polyester fiber, cellulose fiber, aromatic polyamide fiber, Ceramic fiber, fine particle rubber, thermoplastic elastomer, pigment, etc. The reason why fillers are generally used is the effect of improving impact resistance. In addition, when metal hydroxides such as aluminum hydroxide, boehmite, and magnesium hydroxide are used, they have an effect of functioning as a flame-retardant auxiliary agent and improving flame retardancy. The blending amount of these fillers is preferably 1 part by mass to 150 parts by mass, and more preferably 10 parts by mass to 70 parts by mass relative to 100 parts by mass of organic components (excluding organic solvents) in the curable resin composition. If the blending amount is large, there is a concern that the adhesiveness required for use as a laminated sheet may decrease, and there is a concern that the hardened product becomes brittle and sufficient mechanical properties cannot be obtained. In addition, if the blending amount is small, there is a concern that the impact resistance of the cured product is improved, etc., which is not the blending effect of the filler.

When the curable resin composition is used as a plate-shaped substrate or the like, in terms of its dimensional stability, bending strength, and the like, a fibrous filler can be cited as a preferable filler. More preferably, it is a glass fiber substrate in which glass fibers are knitted into a net shape.

In the curable resin composition, various additives such as silane coupling agents, antioxidants, mold release agents, defoamers, emulsifiers, thixotropy imparting agents, smoothing agents, flame retardants, and pigments can be further blended as necessary. These additives are preferably in the range of 0.01% by mass to 20% by mass with respect to the curable resin composition.

The curable resin composition of the present invention can be obtained by uniformly mixing the respective components. Hardening of the curable resin composition can be used to obtain hardened articles such as laminates, cast articles, molded articles, adhesives, insulating layers, and films. As a method for obtaining a cured product, the same method as that of a known epoxy resin composition can be used. The method inherent to the curable resin composition of the present invention is not required, and casting, injection, pouring, dipping, and dripping can be preferably used. Methods such as coating, transfer molding, compression molding, etc., or forming into resin sheets, resin-coated copper foils, prepregs, etc., and laminating them to heat and press hardening to form laminates. The curing temperature at this time is usually in the range of 100°C to 300°C, and the curing time is usually about 10 minutes to 5 hours.

Examples of applications using the curable resin composition include: printed wiring board materials, resin compositions for flexible wiring boards, interlayer insulating materials for build-up substrates, and other insulating materials for circuit boards, semiconductor sealing materials, conductive pastes, conductive films, Adhesive films, resin casting materials, adhesives, etc. for build-up. Among these various applications, printed wiring board materials, insulating materials for circuit boards, and adhesive films for build-up can be used as passive components such as capacitors or active components such as integrated circuit (IC) wafers to be embedded in the substrate The so-called electronic component built-in substrate is used as an insulating material. Among these applications, in terms of properties such as high flame retardancy, high heat resistance, low dielectric properties, and solvent solubility, it is preferable to use printed wiring board materials, resin compositions for flexible wiring boards, and interlayer insulation for build-up substrates. Used in materials for circuit boards (laminates) and semiconductor sealing materials.

When the curable resin composition is made into a plate-like laminate such as a laminate, the filler used is preferably a fibrous filler in terms of its dimensional stability, bending strength, etc., and more preferably glass The fiber is woven into a net-like glass fiber cloth.

By impregnating a fibrous reinforcing base material with a curable resin composition, the prepreg of the present invention used in a printed wiring board or the like can be produced. As the fibrous reinforcing substrate, a woven fabric or non-woven fabric of organic fibers such as inorganic fibers such as glass, polyester resins, etc., polyamine resins, polyacrylic resins, polyimide resins, and aromatic polyamide resins can be used. , But not limited to this. The method for producing a prepreg from an epoxy resin composition is not particularly limited, and it can be obtained, for example, by preparing a varnish-like epoxy resin composition containing the organic solvent and then mixing the organic solvent for adjustment. For a resin varnish with an appropriate viscosity, after the resin varnish is impregnated in the fibrous base material, it is heated and dried to semi-harden the resin component (B-staged). The heating temperature is preferably 50°C to 200°C, and more preferably 100°C to 170°C, depending on the type of organic solvent used. The heating time can be adjusted according to the type of organic solvent used or the curability of the prepreg, and is preferably 1 minute to 40 minutes, more preferably 3 minutes to 20 minutes. At this time, the mass ratio of the epoxy resin composition to the reinforcing substrate used is not particularly limited, but it is generally preferable to adjust so that the resin component in the prepreg becomes 20% by mass to 80% by mass.

The curable resin composition of the present invention can be molded into a sheet shape or a film shape and used. In this case, a conventionally known method can be used for sheeting or filming. The method of manufacturing the adhesive sheet is not particularly limited. For example, it can be obtained by using a reverse roll coater, a cutaway wheel coater, and a mold on a supporting base film that is not dissolved in the resin varnish. The resin varnish is applied by a coater such as a coater, and then heated and dried to B-stage the resin component. In addition, if necessary, another supporting base film is laminated as a protective film on the coated surface (adhesive layer), and dried, thereby obtaining an adhesive sheet having a release layer on both surfaces of the adhesive layer. Examples of the supporting base film include metal foils such as copper foil, polyolefin films such as polyethylene films and polypropylene films, polyester films such as polyethylene terephthalate films, polycarbonate films, silicone films, and polyamides. Among these supporting base films, such as an imine film, a polyethylene terephthalate film having excellent dimensional accuracy and excellent cost without defects such as breakage is preferable. In addition, a metal foil, particularly a copper foil, which facilitates the multilayering of the laminate is preferred. The thickness of the supporting base film is not particularly limited, but it is preferably 10 μm to 150 μm, and more preferably 25 μm to 50 μm in terms of having strength as a support and hardly causing lamination failure. The thickness of the protective film is not particularly limited, but is usually 5 μm to 50 μm. Furthermore, in order to easily peel off the molded adhesive sheet, it is preferable to perform surface treatment with a release agent in advance. In addition, the thickness of the coating resin varnish is preferably 5 μm to 200 μm, and more preferably 5 μm to 100 μm as the thickness after drying. The heating temperature is preferably 50°C to 200°C, and more preferably 100°C to 170°C, depending on the type of organic solvent used. The heating time can be adjusted according to the type of organic solvent used or the curability of the prepreg, and is preferably 1 minute to 40 minutes, more preferably 3 minutes to 20 minutes. The adhesive sheet obtained as described above is usually an insulating adhesive sheet with insulating properties, but it can also be obtained by mixing conductive metal or metal-coated fine particles in an epoxy resin composition. piece. Furthermore, the supporting base film is peeled off after being laminated on the circuit board, or after heating and curing to form an insulating layer. If the support base film is peeled off after heating and hardening the adhesive sheet, it is possible to prevent adhesion of dirt and the like during the hardening step. Here, the insulating adhesive sheet is also an insulating sheet.

The method of manufacturing the laminated board of this invention using the prepreg of this invention or the said insulating adhesive sheet is demonstrated. For example, when a prepreg is used to form a laminate, one or more prepregs are laminated, and metal foils are arranged on one side or both sides to form a laminate, and the laminate is heated under pressure. The prepreg is hardened and integrated to obtain a laminated board. Here, as the metal foil, individual, alloy, or composite metal foils such as copper, aluminum, brass, and nickel can be used. As the conditions for heating and pressing the laminate, as long as the epoxy resin composition is hardened, the heating and pressing can be adjusted appropriately. However, if the pressure is too low, the resulting laminate may be Air bubbles remain inside and the electrical characteristics are reduced. Therefore, it is desirable to pressurize under the condition that satisfies the moldability. The heating temperature is preferably 160°C to 250°C, more preferably 170°C to 220°C. The pressurizing pressure is preferably 0.5 MPa to 10 MPa, more preferably 1 MPa to 5 MPa. The heating and pressing time is preferably 10 minutes to 4 hours, and more preferably 40 minutes to 3 hours. Furthermore, the single-layer laminated board obtained as mentioned above can be made into a multilayer board as an inner layer material. In this case, first, circuit formation is performed on the laminate by an additive method or a subtractive method, and the surface of the formed circuit is treated with an acid solution to perform a blackening treatment to obtain an inner layer material. On one side or both sides of the circuit forming surface of the inner layer material, an insulating layer is formed by using a prepreg or an insulating adhesive sheet, and a conductor layer is formed on the surface of the insulating layer, thereby forming a multilayer board.

In the case of forming an insulating layer using an insulating adhesive sheet, the insulating adhesive sheet is arranged on the circuit forming surface of a plurality of inner layer materials to form a laminate. Alternatively, an insulating adhesive sheet is arranged between the circuit formation surface of the inner layer material and the metal foil to form a laminate. Then, the laminate is heated and pressurized to perform integral molding, thereby forming a cured product of the insulating adhesive sheet as an insulating layer, and forming a multilayered inner layer material. Alternatively, the inner layer material and the metal foil as the conductor layer are formed as a hardened product of the insulating adhesive sheet and used as an insulating layer. Here, the metal foil can use the same metal foil as the metal foil used in the laminated board used as an inner layer material. In addition, the heating and press molding can be performed under the same conditions as the molding of the inner layer material.

In addition, when the insulating layer is formed using the prepreg, one or a plurality of prepregs are arranged on the circuit forming surface of the inner layer material, and a metal foil is arranged on the outer side to form a laminated body. Then, the laminate is heated and pressurized to be integrally molded, thereby forming a hardened prepreg as an insulating layer, and forming a metal foil on the outer side as a conductor layer. Here, the metal foil can be the same as the metal foil used in the laminated sheet used as the inner layer sheet. In addition, the heating and press molding can be performed under the same conditions as the molding of the inner layer material. On the surface of the multilayer build-up board formed as described above, the formation of via holes or the formation of circuits is further performed by an additive method or a subtractive method, and a printed wiring board can be formed. In addition, by using the printed wiring board as an inner layer material and repeating the above-mentioned construction method, it is possible to further form a multilayer multilayer board.

In addition, when a curable resin composition is applied to a laminate to form an insulating layer, the curable grease composition is applied to a thickness of preferably 5 μm to 100 μm, and then the temperature is 100°C to 200°C, preferably It is formed into a sheet by heating and drying at 150°C to 200°C for 1 minute to 120 minutes, preferably 30 minutes to 90 minutes. It is usually formed by a method called a casting method. It is desirable to set the thickness after drying to 5 μm to 150 μm, preferably 5 μm to 80 μm. Furthermore, the viscosity of the curable resin composition is preferably in the range of 10 mPa·s to 40,000 mPa·s at 25°C, more preferably It is 200 mPa·s～30000 mPa·s. On the surface of the multi-layer build-up board formed as described above, the formation of via holes or the formation of circuits is further performed by an additive method or a subtractive method, and a printed wiring board can be formed. In addition, by using the printed wiring board as an inner layer material and repeating the above-mentioned construction method, a multilayer laminated board can be further formed.

The sealing material obtained by using the curable resin composition of the present invention includes tape-like semiconductor wafers, potting type liquid sealing, underfilling, semiconductor interlayer insulating films, etc., and can be preferably used among these. For example, semiconductor packaging molding includes: casting an epoxy resin composition, or molding the epoxy resin composition using a transfer molding machine, an injection molding machine, etc., and then heating at 50°C to 200°C for 2 hours to 10 It is a method of obtaining a molded product in small hours.

In order to prepare the curable resin composition as a semiconductor sealing material, the curable resin composition may be preliminarily mixed with a compounding agent such as an inorganic filler, or a coupling agent, a mold release agent, etc., as necessary, and then used for extrusion. Discharge machine, kneader, roller, etc. fully melt and mix until uniform. In this case, silica is generally used as an inorganic filler. In this case, it is preferable to blend the inorganic filler in the curable resin composition at a ratio of 70% by mass to 95% by mass. In the case where the curable resin composition obtained as described above is used as a tape-like sealing material, it can be exemplified by heating it to produce a semi-cured sheet, and after making a sealing material tape, the sealing material tape is placed on A method of forming a semiconductor wafer by heating to 100°C to 150°C to soften it, and then completely hardening it at 170°C to 250°C. In addition, in the case of using as a potting type liquid sealing material, the curable resin composition obtained is dissolved in a solvent as necessary, and then applied to a semiconductor wafer or electronic component and directly cured.

In addition, the curable resin composition of the present invention can also be used as a resist ink. In this case, the epoxy resin composition may include a vinyl monomer having an ethylenically unsaturated double bond, a cationic polymerization catalyst as a hardener, and a pigment, talc, and filler to prepare a resist. After the ink composition is applied on a printed circuit board by a screen printing method, a method of forming a cured resist ink. The curing temperature at this time is preferably in the temperature range of about 20°C to 250°C.

The cured product of the present invention can take the form of a laminate, a molded product, an adhesive, a coating film, a film, and the like. A curable resin composition was prepared, and the cured epoxy resin of the laminate was evaluated by heating and curing. As a result, the specific epoxy resin (a) and the isocyanate compound (b) were reacted to obtain the oxazolidine-containing compound of the present invention Compared with the conventionally known epoxy resins, the epoxy resin composition of the ketone ring not only has low dielectric properties, and further has low viscosity and good workability, but also has high flame retardancy and high adhesiveness. , And the solvent solubility is also improved. [Example]

Hereinafter, examples and comparative examples are given to specifically describe the present invention, but the present invention is not limited to these. Unless otherwise specified, "parts" means parts by mass, and "%" means parts by mass. The measurement method can be measured according to the following methods, respectively. The unit of equivalent is "g/eq.".

(1) Epoxy equivalent: Measured in accordance with JIS K7236. Specifically, a potentiometric titration apparatus was used, methyl ethyl ketone was used as a solvent, a tetraethylammonium bromide acetic acid solution was added, and a 0.1 mol/L perchloric acid-acetic acid solution was further used. (2) Softening point: Measured in accordance with JIS K7234 standard and ring and ball method. Specifically, an automatic softening point device (manufactured by Meitec Co., Ltd., ASP-MG4) was used. (3) Number average molecular weight (Mn), weight average molecular weight (Mw), and degree of dispersion (Mw/Mn): The main body (manufactured by Tosoh Co., Ltd., HLC-8220GPC) uses a series of pipe columns (Tosoh) TSKgelG4000HXL, TSKgelG3000HXL, TSKgelG2000HXL) manufactured by Tosoh Co., Ltd., and the column temperature is set to 40°C. In addition, tetrahydrofuran was used as the eluent at a flow rate of 1 mL/min, and a differential refraction detector was used as the detector. Mn, Mw, and Mw/Mn were converted using a calibration curve obtained from standard monodisperse polystyrene. (4) Solvent solubility: Visually judge the state when diluted with toluene to 50% non-volatile content. The case where it is completely dissolved and transparent is referred to as "○", the case where it is cloudy or separated is referred to as "×", and the case where it is slightly turbid is referred to as "△".

(5) Glass transition temperature: Measured in accordance with JIS K7121 standard and differential scanning calorimetry. Exter (EXTER) DSC6200 manufactured by SII Company was used to measure from 20°C at a temperature increase rate of 10°C/min, and the extrapolated glass transition onset temperature (Tig) of the DSC chart obtained in the second cycle ) And find out. (6) Copper foil peeling strength and interlayer adhesion: Measured in accordance with JIS C6481. The interlayer adhesion is measured by peeling between the 7th layer and the 8th layer. (7) Relative permittivity and dielectric loss tangent: According to IPC-TM-650 2.5.5.9, using a material analyzer (manufactured by AGILENT Technologies), the capacitance method is used to measure the permittivity and the frequency of 1 GHz. Dielectric loss tangent. (8) Flame retardancy: According to UL94 (Underwriters Laboratories Inc.'s safety certification standard), it was evaluated by the vertical method, and the total flame retention time (second) of 5 test pieces was shown. A small residual flame time indicates more preferable flame retardancy.

Synthesis Example 1 In a reaction device equipped with a stirring device, a thermometer, a nitrogen introduction device, a cooling pipe, and a water separator, at room temperature, 100 parts of 4,4'-(3,3,5-trimethyl) Cyclohexylidene) diphenol (manufactured by Benzhou Chemical Industry Co., Ltd., BisP-TMC), 358 parts of epichlorohydrin, and 4 parts of ion-exchanged water were heated to 50°C while stirring. After uniformly dissolving, 5.3 parts of 49% sodium hydroxide aqueous solution was charged and reacted for 3 hours. Secondly, after the temperature was raised to 64°C, the pressure was reduced to such an extent that water reflux was generated, 48 parts of 49% sodium hydroxide aqueous solution was added dropwise over 3 hours, and the refluxing distilled water was separated from the surface by the separation tank in the dropwise addition. Chlorohydrin, the epichlorohydrin is returned to the reaction vessel, and the water is removed to the outside of the system to perform the reaction. After the reaction, the temperature was increased to 70°C to perform dehydration, and the temperature was set to 135°C to recover the remaining epichlorohydrin. Return to normal pressure, add 204 parts of methyl isobutyl ketone (MIBK) to dissolve. 127 parts of ion-exchanged water was added, and the mixture was stirred and left to stand to dissolve the by-produced salt in the water to remove it. Next, 2.9 parts of 49% sodium hydroxide aqueous solution was charged, and stirring reaction was performed at 80 degreeC for 90 minutes, and purification reaction was performed. MIBK was added, and ionic impurities were removed by washing with water several times. The solvent is recovered to obtain the epoxy resin (epoxy resin a) represented by the formula (1). The epoxy equivalent of the obtained epoxy resin a was 216, the alcoholic hydroxyl equivalent was 5510, and the average value of m was 0.04.

(Epoxy resin) Epoxy resin a: The epoxy resin obtained in Synthesis Example 1 Epoxy resin b: Biphenyl type epoxy resin (manufactured by Mitsubishi Chemical Corporation, YX-4000, epoxy equivalent 196, alcoholic hydroxyl equivalent 5000 ) Epoxy resin c: Biphenyl aralkyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., NC-3000, epoxy equivalent 275, alcoholic hydroxyl equivalent 4520)

(Isocyanate compound) Isocyanate A: a mixture of 2,4-toluene diisocyanate (65%) and 2,6-toluene diisocyanate (35%) (manufactured by Mitsui Chemicals SKC Polyurethane Co., Ltd., Cosmo Cosmonate (registered trademark) T-65, NCO concentration 48%) Isocyanate B: 2,4'-diphenylmethane diisocyanate (50%) and 4,4'-diphenylmethane diisocyanate (50%) %) (BASF INOAC Polyurethane Co., Ltd., Lupranate (registered trademark) MI, NCO concentration 33%) Isocyanate C: Polymethylene poly Phenyl polyisocyanate (BASF INOAC Polyurethane Co., Ltd., Lupranate (registered trademark) M20S, NCO concentration 31%)

(Catalyst) TMAI: Tetramethylammonium iodide (manufactured by Tokyo Chemical Industry Co., Ltd., reagent)

(Hardener) PN: phenol novolac resin (manufactured by Showa Denko Co., Ltd., shonol (registered trademark) BRG-557, softening point 80°C, phenolic hydroxyl equivalent 105) DCPD: dicyclopentadiene /Phenol co-condensation resin (manufactured by Kunei Chemical Co., Ltd., GDP9140, phenolic hydroxyl equivalent 196) DICY: Dicyandiamine (manufactured by Japan Carbide Industry Co., Ltd., DIHARD, active hydrogen equivalent 21) SMA: styrene/ Maleic acid copolymer resin (manufactured by Cray Valley, SMA2000, acid anhydride equivalent 316)

(Hardening accelerator) 2E4MZ: 2-ethyl-4-methylimidazole (manufactured by Shikoku Chemical Industry Co., Ltd., Curezol (registered trademark) 2E4MZ)

(Flame retardant) LC-950: Phenolic hardener containing phosphorus (manufactured by Shin-AT&C, LC-950PM60, phenolic hydroxyl equivalent 341, phosphorus content 9.3%, propylene glycol monomethyl ether solution, non-volatile content 60%) SPB-100: Phosphononitrile-based flame retardant (manufactured by Otsuka Chemical Co., Ltd., SPB-100, 13% phosphorus content)

Example 1 40 parts of epoxy resin a as epoxy resin (a1), 60 parts of epoxy resin b as epoxy resin (a2), and 0.1 parts As a catalyst, TMAI was heated while introducing nitrogen gas, and the temperature was maintained at 120°C for 30 minutes to remove water in the system. Next, while maintaining the reaction temperature of 130° C. to 140° C., 8.6 parts (modification rate: 20 mol%) of isocyanate A as the isocyanate compound (b) was dropped over 3 hours. After the dropping was completed, stirring was continued for 3 hours while maintaining the same temperature to obtain an epoxy resin composition (resin 1) containing an oxazolidinone ring. With respect to the obtained epoxy resin composition containing an oxazolidinone ring, epoxy equivalent, softening point, molecular weight distribution, and solvent solubility were measured. In addition, the so-called modification rate means the percentage of the modification rate of the isocyanate group of the isocyanate compound (b) relative to 1 equivalent of epoxy group of the epoxy resin (a) [(b)/(a)× 100]. Here, (a) and (b) represent the number of moles of the epoxy group of the epoxy resin (a) and the number of moles of the isocyanate group of the isocyanate compound (b). The measurement results are shown in Table 1.

Example 2 to Example 8 According to the loading amount (parts) of each raw material shown in Table 1, the same device as in Example 1 was used and the same operation was used to synthesize an epoxy resin composition containing an oxazolidinone ring Things. The epoxy equivalent, softening point, molecular weight distribution, and solvent solubility of the obtained oxazolidinone ring-containing epoxy resin composition were measured in the same manner as in Example 1. The measurement results are shown in Table 1. The epoxy resin composition containing the oxazolidinone ring obtained in these Examples 2 to 8 was referred to as Resin 2 to Resin 8.

[Table 1]

Comparative Example 1 to Comparative Example 7 Set the loading amount (part) of each raw material shown in Table 2, using the same device as in Example 1, and using the same operation to synthesize an epoxy resin containing an oxazolidinone ring Composition. The epoxy equivalent, softening point, molecular weight distribution, and solvent solubility of the obtained oxazolidinone ring-containing epoxy resin composition were measured in the same manner as in Example 1, and the measurement results are shown in Table 2. The epoxy resin composition containing the oxazolidinone ring obtained in these comparative examples 1 to 7 was referred to as resin H1 to resin H7.

[Table 2]

Example 9 100 parts of resin 1, 38 parts of PN as a hardening agent, and 0.12 parts of 2E4MZ as a hardening accelerator were prepared and dissolved in MEK, propylene glycol monomethyl ether, N,N-di The curable resin composition varnish is obtained in a mixed solvent prepared from methylformamide.

The obtained curable resin composition varnish was impregnated in a glass cloth (manufactured by Nittobo Co., Ltd., WEA 116E106S136, thickness 0.1 mm). The impregnated glass cloth was dried in a hot air circulating oven at 150°C for 11 minutes to obtain a prepreg. Put 8 pieces of the obtained prepreg on top and bottom of copper foil (manufactured by Mitsui Metal Mining Co., Ltd., 3EC-III, thickness 35 μm), and perform 2 MPa vacuum pressing to obtain a 1.0 mm thick laminate. Table 3 shows the results of the glass transition temperature, copper foil peel strength, and interlayer adhesion of the laminate.

In addition, the obtained prepreg was unwound, and a powdered prepreg powder that passed through 100 mesh was made with a sieve. Put the obtained prepreg powder into a mold made of fluororesin, and perform vacuum pressing of 2 MPa under the temperature conditions of 130°C×15 minutes + 190°C×80 minutes to obtain a 50 mm square × 2 mm thick test piece . Table 3 shows the results of the relative dielectric constant and dielectric loss tangent of the test piece.

Example 10 to Example 20 The resin 2 to resin 18, epoxy resin c, PN, and 2E4MZ of Example 2 to Example 8 were prepared with the blending amounts (parts) in Table 3 and Table 4. The same as in Example 9 The same operation was performed on the device to obtain a laminate and a test piece. The same test as in Example 9 was performed, and the results are shown in Table 3 and Table 4.

[table 3]

[Table 4]

Comparative Example 8 to Comparative Example 13 The resins H1 to H7, other epoxy resins c, PN, and 2E4MZ of Comparative Example 1 to Comparative Example 7 were blended with the blending amounts (parts) in Table 5, and the same equipment as in Example 9 was used. The same operation was performed to obtain a laminate and a test piece. The same test as in Example 9 was performed, and the results are shown in Table 5.

[table 5]

Example 21 to Example 26 The resin 1, resin 6, resin 7, resin 8, PN, 2E4MZ and flame retardant of Example 1 to Example 8 were prepared with the blending amount (parts) of the formula in Table 6, and used and implemented The same device as in Example 9 uses the same operation to obtain a laminate and a test piece. The same test as in Example 9 was performed, and the results are shown in Table 6. In addition, both sides of the obtained laminated board were etched to prepare test pieces for flame retardancy measurement, and the flame retardancy test was performed. The results are shown in Table 6.

[Table 6]

Comparative Example 16 to Comparative Example 19 Resin H1 to Resin H7, PN, 2E4MZ, and flame retardant of Comparative Example 1 to Comparative Example 7 were prepared with the blending amounts (parts) of the formulations in Table 7, and the same equipment as in Example 9 was used , Use the same operation to obtain laminates and test pieces. The same test as in Example 9 was performed, and the results are shown in Table 7. In addition, both sides of the obtained laminated board were etched to prepare test pieces for flame retardancy measurement, and the flame retardancy test was performed. The results are shown in Table 7.

[Table 7]

without.

without.

Claims (14)

An epoxy resin composition containing an oxazolidinone ring, which is an epoxy resin composition containing an oxazolidinone ring obtained from an epoxy resin (a) and an isocyanate compound (b), and is characterized in that: The epoxy resin (a) is a mixture of an epoxy resin (a1) represented by the following formula (1) and an epoxy resin (a2) represented by the following formula (2) as essential components, and the epoxy resin (a1) is 5% by mass to 50% by mass, and the total amount of epoxy resin (a1) and epoxy resin (a2) is 55% by mass to 100% by mass;

In the formula, X is a ring member having at least one substituent selected from the group consisting of an alkyl group with 1 to 4 carbons, an aryl group with 6 to 10 carbons, and an aralkyl group with 7 to 11 carbons. A cycloalkylene group of 5 to 8; R ¹ and R ² are each independently an alkyl group with 1 to 8 carbons, a cycloalkyl group with 5 to 8 carbons, an alkenyl group with 1 to 4 carbons, and 6 carbons. ~10 aryl group or carbon number 7-10 aralkyl group, k1 and k2 are each independently an integer of 0-4; G is glycidyl; m and n represent the number of repetitions, and the average value is 0-2. The epoxy resin composition containing an oxazolidinone ring as described in claim 1, wherein the alcoholic hydroxyl group equivalent of the epoxy resin (a) is 1000 g/eq. or more. The epoxy resin composition containing an oxazolidinone ring as described in the first or second item of the scope of patent application, wherein the isocyanate compound (b) has an average of 1.8 or more isocyanate groups in the molecule. The epoxy resin composition containing oxazolidinone ring as described in item 1 or item 2 of the scope of patent application has an epoxy equivalent of 200 g/eq. to 600 g/eq. The epoxy resin composition containing the oxazolidinone ring as described in item 1 or item 2 of the scope of patent application has a softening point of 50°C to 150°C. A method for producing an epoxy resin composition containing an oxazolidinone ring, characterized in that, in the presence of a catalyst, the epoxy resin represented by the following formula (1) ( a1) and an epoxy resin (a) containing a total of 55% to 100% by mass of the epoxy resin (a1) and the epoxy resin (a2) represented by the following formula (2), and the isocyanate compound (b) )reaction;

In the formula, X is one having at least one substituent selected from the group consisting of an alkyl group with 1 to 4 carbons, an aryl group with 6 to 10 carbons, and an aralkyl group with 7 to 11 carbons, and a ring member with 5 to 8 Cycloalkylene; R ¹ and R ² are each independently an alkyl group with 1 to 8 carbons, a cycloalkyl group with 5 to 8 carbons, an alkenyl group with 1 to 4 carbons, and an aryl group with 6 to 10 carbons. Or an aralkyl group with 7 to 10 carbon atoms, k1 and k2 are each independently an integer of 0 to 4; G is a glycidyl group; m and n represent the number of repetitions, and the average value is 0 to 2. The method for producing an epoxy resin composition containing an oxazolidinone ring as described in claim 6, wherein the alcoholic hydroxyl equivalent of the epoxy resin (a) is 1000 g/eq. or more. The method for producing an epoxy resin composition containing an oxazolidinone ring as described in item 6 or item 7 of the scope of patent application, wherein the isocyanate compound (b) has an average of 1.8 or more isocyanate groups in the molecule . The method for producing an epoxy resin composition containing an oxazolidinone ring as described in item 6 or item 7 of the scope of the patent application, wherein the epoxy resin (a) has 1 molar group of The isocyanate group of the isocyanate compound (b) is in the range of 0.02 mol or more and less than 0.5 mol. A curable resin composition characterized in that the epoxy resin composition containing the oxazolidinone ring described in any one of items 1 to 5 of the scope of patent application and a hardener are used as essential components. The curable resin composition according to claim 10, wherein the curing agent is an epoxy resin curing agent having an active hydrogen group, and is relative to all epoxy resins in the curable resin composition. The active hydrogen group of the hardener is 0.2 mol~1.5 mol. A hardened product characterized by hardening the hardenable resin composition described in item 10 or item 11 of the scope of patent application. A prepreg characterized in that it is obtained from the curable resin composition described in item 10 or item 11 of the scope of patent application. A laminated board, characterized in that it is obtained from the curable resin composition described in item 10 or item 11 of the scope of patent application.