Polyfunctional vinyl resin, method for producing same, polyfunctional vinyl resin composition, and cured product thereof

Abstract

Provided is a resin material which has high storage stability, shows a low dielectric constant and a low dielectric loss tangent, and also has high heat resistance. A polyfunctional vinyl resin represented by general formula (1). In the formula (1), R1 independently represents a C1-8 hydrocarbon group, X independently represents a hydrogen atom or a vinyl group-containing group represented by formula (1a), at least one is a vinyl group-containing group, and R2 is a hydrogen atom or a C1-8 alkyl group or alkenyl group. I represents an integer of 1-3, and n represents a number of repetitions, the average value of which is 1-5. # imgabs0 #--CO-CR2 = CH2 (1a), and a method for manufacturing the same.

Description

Technical Field

[0001] The present invention relates to a polyfunctional vinyl resin and a polyfunctional vinyl resin composition having a low dielectric loss tangent, high heat resistance, and high storage stability, which can be used for printed circuit boards, sealing materials, casting materials, etc. for electronic devices, and a cured product thereof. Background Art

[0002] With the increase in information communication volume in recent years, information communication in high frequency bands has become prevalent. In order to obtain more excellent electrical properties, especially to reduce transmission loss in high frequency bands, an electrical insulating material having a low dielectric constant and a low dielectric loss tangent is required. Further, since printed circuit boards or electronic components using these electrical insulating materials are exposed to high-temperature reflow soldering during installation, a material having high heat resistance, that is, a high glass transition temperature, is desired. In particular, recently, due to environmental problems, lead-free solders having a high melting point are used, and thus the demand for electrical insulating materials having even higher heat resistance has increased. For these requirements, cured resins using vinyl resins having various chemical structures have been proposed so far.

[0003] As such a cured resin, for example, a cured resin such as a divinylbenzyl ether resin of bisphenol or a polyvinylbenzyl ether resin of a phenol novolak type has been proposed (Patent Document 1, Patent Document 2). However, these vinylbenzyl ether resins not only do not provide sufficient dielectric properties but also have insufficient heat resistance.

[0004] As vinylbenzyl ether resins having improved these properties, vinylbenzyl ether resins having several specific structures have been proposed and attempts have been made to improve heat resistance (Patent Document 3, Patent Document 4, Patent Document 5). However, the improvement of the properties cannot be said to be sufficient, and further improvement of the properties is desired.

[0005] A polyfunctional vinyl resin composition is disclosed, which is characterized by containing a polyfunctional vinyl resin obtained by vinylbenzyl etherifying at least one hydroxyl group selected from a phenol aralkyl resin, a naphthol aralkyl resin, a biphenyl type phenol novolak resin, and a biphenyl type naphthol novolak resin (Patent Document 6). However, the vinylbenzyl etherified polyfunctional vinyl resin synthesized according to the manufacturing method disclosed therein has a large total halogen content and a large amount of residual vinyl aromatic halomethyl compounds, and thus the dielectric loss tangent and heat resistance do not satisfy those of an insulating material corresponding to high frequencies, and in terms of moldability, molding defects are likely to occur, and it is not a desired material.

[0006] It is known to carry out vinylbenzylation of the phenolic hydroxyl groups of a polyfunctional phenyl ether oligomer obtained by reacting a polyphenol having three or more and less than nine phenolic hydroxyl groups in the molecule and having an alkyl or alkylene group at the 2- and 6-positions of at least one of the phenolic hydroxyl groups with a monophenol compound (Patent Document 7). However, the vinylbenzyl ether resin obtained by this technique has a high viscosity, and thus has a high molding processing temperature, and if exposed to a high temperature in an air atmosphere, the dielectric loss tangent deteriorates significantly.

[0007] Techniques related to methacryloyl-terminated PPE in which the phenolic hydroxyl groups of a polyfunctional phenyl ether (PPE) oligomer are capped with methacryloyl groups have also been widely proposed. In order to improve the convenience during prepreg manufacture, the molecular weight of PPE is reduced, or the solubility in a solvent is improved by using a PPE having a branched structure (Patent Documents 8 and 9). However, since the molecular weight of PPE is reduced, a decrease in dielectric properties and heat resistance is found. In addition, the effect of improving the solvent solubility due to the introduction of the branched structure is also limited, and further improvement is required.

[0008] Therefore, existing vinyl resins do not form a cured product that has both a low dielectric loss tangent required for use as an electrical insulating material, particularly for high-frequency applications, and high heat resistance that can withstand lead-free solder processing. In addition, they are also insufficient in terms of reliability and processability.

[0009] Prior Art Documents

[0010] Patent Documents

[0011] Patent Document 1: Japanese Patent Laid-Open No. 63-68537

[0012] Patent Document 2: Japanese Patent Laid-Open No. 64-65110

[0013] Patent Document 3: Japanese Patent Publication No. 1-503238

[0014] Patent Document 4: Japanese Patent Laid-Open No. 9-31006

[0015] Patent Document 5: Japanese Patent Laid-Open No. 2004-323730

[0016] Patent Document 6: Japanese Patent Laid-Open No. 2003-306591

[0017] Patent Document 7: Japanese Patent Laid-Open No. 2007-308685

[0018] Patent Document 8: Japanese Patent Publication No. 2003-515642

[0019] Patent Document 9: Japanese Patent Laid-Open No. 2021-109944 Summary of the Invention

[0020] An object of the present invention is to provide a polyfunctional vinyl resin and a resin composition thereof that have a cured product with high storage stability, a low dielectric constant, a low dielectric loss tangent, and a high glass transition temperature, and the purpose is to provide a resin composition, a cured product, or a material containing the same that can be used as a dielectric material, an insulating material, and a heat-resistant material in fields such as the electrical and electronic industries and the aerospace industry.

[0021] To solve the problem, the present inventors conducted in-depth research and as a result found that: by using a polyfunctional vinyl resin represented by the following general formula (1), the above problems can be solved, and the present invention has been completed.

[0022] That is, the present invention is a polyfunctional vinyl resin represented by the following general formula (1).

[0023]

[0024] -CO-CR 2 =CH2 (1a)

[0025] In the formula, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, X independently represents a hydrogen atom or a vinyl group-containing group represented by the above formula (1a), at least one is a vinyl group-containing group, R2 is a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms. i is an integer of 1 to 3, n represents the number of repetitions, and its average value is a number of 1 to 5.

[0026] The present invention is a method for producing a polyfunctional vinyl resin, which is a method for producing the above polyfunctional vinyl resin, characterized in that dicyclopentadiene is reacted with a phenol having a substituent represented by the following general formula (2) at a ratio of 0.08 to 0.80 times the molar amount, and after obtaining a polyhydric hydroxyl resin represented by the following general formula (3), the obtained polyhydric hydroxyl resin is reacted with one or more of an acid anhydride represented by the following general formula (4a) or an acyl halide represented by the following general formula (4b). Preferably, for the obtained polyfunctional vinyl resin as a reactant, the solvent and volatile impurities are removed under reduced pressure in a temperature range of 100 to 180 °C to make it a solid.

[0027]

[0028] Among them, R1 and i have the same meanings as defined in the above general formula (1), respectively.

[0029]

[0030] Among them, R1, i, and n have the same meanings as defined in the above general formula (1), respectively.

[0031]

[0032] Among them, R3 has the same definition as R2 in the above formula (1a), and R4 represents a halogen.

[0033] The present invention is a polyfunctional vinyl resin composition, which contains a polyfunctional vinyl resin and a radical polymerization initiator as essential components; and a cured product of the polyfunctional vinyl resin obtained by curing it.

[0034] Furthermore, it is a prepreg comprising a semi-cured product of the polyfunctional vinyl resin composition and a fibrous substrate, a resin sheet including a support film; a laminate formed by laminating and molding these prepregs and / or resin sheets.

[0035] The polyfunctional vinyl resin and the resin composition of the present invention have high storage stability. Furthermore, the cured product obtained by curing the resin composition has a low dielectric constant and a low dielectric loss tangent, and high heat resistance, and is suitable as an electronic material for high-speed communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The GPC chart of the polyfunctional vinyl resin obtained in Example 1 is shown.

[0037] Figure 2 The IR chart of the polyfunctional vinyl resin obtained in Example 1 is shown. DETAILED DESCRIPTION OF THE INVENTION

[0038] The present invention will be described in detail below.

[0039] The polyfunctional vinyl resin of the present invention is represented by the following general formula (1).

[0040]

[0041] In general formula (1), R1 represents a hydrocarbon group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 8 carbon atoms, an aralkyl group having 7 to 8 carbon atoms, or an allyl group. As the alkyl group having 1 to 8 carbon atoms, any of linear, branched, or cyclic forms may be used, and examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, methylbutyl, n-hexyl, dimethylbutyl, n-heptyl, methylhexyl, trimethylbutyl, n-octyl, dimethylpentyl, ethylpentyl, isooctyl, ethylhexyl, etc. hydrocarbon groups, cyclohexyl, cycloheptyl, cyclooctyl, methylcyclohexyl, dimethylcyclohexyl, ethylcyclohexyl, methylcycloheptyl, etc. cycloalkyl groups having 5 to 8 carbon atoms, but are not limited thereto. As the aryl group having 6 to 8 carbon atoms, phenyl, tolyl, xylyl, ethylphenyl, etc. may be mentioned, but are not limited thereto. As the aralkyl group having 7 to 8 carbon atoms, benzyl, α-methylbenzyl, etc. may be mentioned, but are not limited thereto. Among these substituents, from the viewpoints of ease of acquisition and reactivity during formation of the cured product, methyl or phenyl is preferred, and methyl is particularly preferred. Regarding the substitution position of R1, relative to the oxy group, any of ortho, meta, and para positions may be used, and the ortho position is preferred.

[0042] i is the number of substitutions of R1, which is 1 to 3, preferably 1 or 2, more preferably 2.

[0043] In general formula (1), X independently represents a hydrogen atom or a vinyl-containing group represented by the following formula (1a), and at least one is a vinyl-containing group, which is a group derived from a vinyl-containing acid anhydride or acyl halide as a raw material.

[0044] -CO-CR 2 =CH2 (1a) In formula (1a), R2 is a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms. As the alkyl group, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl, etc. may be mentioned. As the alkenyl group, for example, vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, and octenyl, etc. may be mentioned. R2 is preferably a hydrogen atom or methyl.

[0045] In general formula (1), n is the number of repetitions, representing a number of 1 or more, and representing a number of 1 to 5 on average, preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and further preferably 1.0 to 2.0. The average value is the number average.

[0046] The average molecular weight of the polyfunctional vinyl resin of the present invention is preferably 400 to 2000, more preferably 450 to 1000, in terms of weight average molecular weight (Mw), and the number average molecular weight (Mn) is preferably 300 to 2000, more preferably 400 to 1000, and further preferably 450 to 800.

[0047] The vinyl equivalent (g / eq.) is preferably 200 to 600, more preferably 220 to 400, and still more preferably 250 to 350. On the other hand, the hydroxyl equivalent (g / eq.) is preferably 10,000 or more, more preferably 15,000 or more, and particularly preferably in the range of 20,000 to 30,000.

[0048] As the molecular weight distribution, the content of the n = 1 component is preferably 50 to 95 area%, more preferably 60 to 90 area%, and the content of the n = 2 component or higher is 5 to 50 area%, preferably 10 to 40 area%.

[0049] The polyfunctional vinyl resin of the present invention can be suitably obtained by reacting a polyhydric hydroxyl resin represented by the following general formula (3) with an acid anhydride represented by the following general formula (4a) or an acyl halide represented by the following general formula (4b).

[0050]

[0051] In the general formula (3), R1 and n have the same meanings as defined in the above general formula (1).

[0052] In the general formulas (4a) and (4b), R3 is a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms. Examples of the alkyl group include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl. Examples of the alkenyl group include vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, and octenyl. From the viewpoints of ease of acquisition and reactivity when forming a cured product, R3 is preferably a hydrogen atom or a methyl group.

[0053] R4 represents a halogen, preferably a chlorine atom or a bromine atom.

[0054] The polyhydric hydroxyl resin represented by the general formula (3) can be obtained, for example, by reacting a phenol having a substituent represented by the following general formula (2) with dicyclopentadiene in the presence of a Lewis acid such as a boron trifluoride-ether catalyst.

[0055]

[0056] In the general formula (2), R1 and i have the same meanings as R1 and i in the above general formula (1), respectively, and the preferred substituents are also the same.

[0057] Examples of the substituted phenols described above include cresol, ethylphenol, propylphenol, isopropylphenol, n-butylphenol, tert-butylphenol, amylphenol, isoamylphenol, neopentylphenol, cyclopentylphenol, hexylphenol, (methylpentyl)phenol, (dimethylbutane)phenol, cyclohexylphenol, phenylphenol, tolylphenol, xylenylphenol, benzylphenol, α-methylbenzylphenol, allylphenol, dimethylphenol, diethylphenol, dipropylphenol, diisopropylphenol, di(n-butyl)phenol, di(tert-butyl)phenol, dipentylphenol, diisoamylphenol, dineopentylphenol, dicyclopentylphenol, dihexylphenol, dicyclohexylphenol, diphenylphenol, di(tolyl)phenol, di(xylenyl)phenol, dibenzylphenol, bis(α-methylbenzyl)phenol, methylethylphenol, methyl tert-butylphenol, methylallylphenol, tolylphenylphenol, etc. From the viewpoints of ease of availability and reactivity when forming a cured product, cresol, phenylphenol, benzylphenol, dimethylphenol, diphenylphenol, and dibenzylphenol are preferred, and cresol, phenylphenol, and dimethylphenol are particularly preferred.

[0058] As the substitution position, the ortho position is preferred, and 2,6-disubstituted phenols represented by the following general formula (2-1) having two substituents are more preferred.

[0059]

[0060] R1 has the same meaning as defined in the above general formula (2).

[0061] Examples of the above 2,6-disubstituted phenols include 2,6-dimethylphenol, 2,6-diethylphenol, 2,6-dipropylphenol, 2,6-diisopropylphenol, 2,6-di(n-butyl)phenol, 2,6-di(tert-butyl)phenol, 2,6-dihexylphenol, 2,6-dicyclohexylphenol, 2,6-diphenylphenol, 2,6-di(tolyl)phenol, 2,6-dibenzylphenol, 2,6-bis(α-methylbenzyl)phenol, 2-ethyl-6-methylphenol, 2-allyl-6-methylphenol, 2-tolyl-6-phenylphenol, etc. From the viewpoints of ease of availability and reactivity when forming a cured product, 2,6-diphenylphenol and 2,6-dimethylphenol are preferred, and 2,6-dimethylphenol is particularly preferred.

[0062] The catalyst used for the above reaction is a Lewis acid, specifically boron trifluoride, boron trifluoride-phenol complex, boron trifluoride-ether complex, aluminum chloride, tin chloride, zinc chloride, iron chloride, etc. Among them, from the viewpoint of ease of handling, boron trifluoride-ether complex is preferred. When using boron trifluoride-ether complex as the catalyst, the amount used is 0.001 to 20 parts by mass, preferably 0.5 to 15 parts by mass, relative to 100 parts by mass of dicyclopentadiene.

[0063] Regarding the ratio of phenols to dicyclopentadiene in the reaction, relative to 1 mole of phenols, the amount of dicyclopentadiene is 0.08 to 0.80 mole, preferably 0.09 to 0.60 mole, more preferably 0.10 to 0.50 mole, further preferably 0.10 to 0.40 mole, and particularly preferably 0.10 to 0.20 mole. In this reaction, not only the polyhydroxy resin represented by the general formula (3) is sometimes included, but also a structure in which the dicyclopentadiene structure is bonded to the hydroxyl group of phenol.

[0064] The hydroxyl equivalent (g / eq.) of the polyfunctional hydroxy resin is preferably 150 to 500, more preferably 160 to 300, and most preferably 170 to 250. In terms of the average molecular weight, the weight-average molecular weight (Mw) is preferably 300 to 1000, more preferably 400 to 700, and the number-average molecular weight (Mn) is preferably 300 to 1000, more preferably 400 to 700. The softening point is preferably 50 to 100 °C, more preferably 60 to 90 °C.

[0065] As the reaction method, it can be a method of charging phenols having a substituent and a catalyst into a reactor and dropping dicyclopentadiene over 1 to 10 hours.

[0066] As the reaction temperature, it is preferably 50 to 200 °C, more preferably 100 to 180 °C, and further preferably 120 to 160 °C. The reaction time is preferably 1 to 10 hours, more preferably 3 to 10 hours, and further preferably 4 to 8 hours.

[0067] After the reaction is completed, an alkali such as sodium hydroxide, potassium hydroxide, or calcium hydroxide is added to deactivate the catalyst. Then, a solvent such as aromatic hydrocarbons like toluene and xylene, and ketones like methyl ethyl ketone and methyl isobutyl ketone is added to dissolve it. After washing with water, the solvent is recovered under reduced pressure, and thus the target phenolic resin can be obtained. It should be noted that it is preferable to react as much dicyclopentadiene as possible, leaving a part of the phenols having a substituent unreacted. It is preferably 10% or less unreacted, and this is recovered under reduced pressure.

[0068] During the reaction, according to the need for viscosity adjustment, etc., solvents such as aromatic hydrocarbons like benzene, toluene, and xylene, halogenated hydrocarbons like chlorobenzene and dichlorobenzene, ethers like ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, and ketones like methyl isobutyl ketone, cyclopentanone, and cyclohexanone can be used.

[0069] The polyfunctional vinyl resin of the present invention can be suitably obtained by reacting the polyhydroxy resin thus obtained with an acid anhydride represented by the general formula (4a) containing a vinyl group or an acyl halide represented by the general formula (4b).

[0070]

[0071] Examples of the acid anhydride of formula (4a) containing a vinyl group include acrylic anhydride, methacrylic anhydride, etc., and methacrylic anhydride is preferred. Examples of the acyl halide of formula (4b) containing a vinyl group include acryloyl chloride, methacryloyl chloride, methacryloyl bromide, etc., and methacryloyl chloride and methacryloyl bromide are preferred.

[0072] Regarding the reaction of the polyhydroxy resin with the vinyl group-containing acid anhydride or acyl halide, a method of reacting the polyhydroxy resin in a solvent in the presence of a basic compound can be mentioned. In this case, it can be a method of dissolving the polyhydroxy resin, the basic compound, and the solvent in a reactor and then adding the acid anhydride or acyl halide and reacting them.

[0073] Regarding the usage ratio of the polyhydroxy resin to the vinyl group-containing acid anhydride or acyl halide, relative to 1 equivalent of the phenolic hydroxyl group of the polyhydroxy resin, it is advisable to react in such a way that the acid anhydride or acyl halide preferably becomes 0.5 to 2.0 equivalents, more preferably 0.8 to 1.5 equivalents.

[0074] The solvent used for the production of the polyfunctional vinyl resin of the present invention is not particularly limited. For example, aromatic hydrocarbons such as benzene, toluene, and xylene, halogenated hydrocarbons such as chlorobenzene and dichlorobenzene, ethers such as tetrahydrofuran, dioxane, diethylene glycol dimethyl ether, cyclopentyl methyl ether, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone, alcohols such as methanol, ethanol, n-propanol, isopropanol, and n-butanol, aprotic polar solvents such as dimethylacetamide, dimethylformamide, and dimethyl sulfoxide, etc. One or more of these solvents can be used. Water can also be used in combination with the above solvents.

[0075] Regarding the amount of the solvent used, relative to the total mass of the polyhydroxy resin, it is preferably 20 to 300% by mass, more preferably 25 to 250% by mass, and particularly preferably 25 to 200% by mass. In particular, aprotic polar solvents cannot be used for purification such as water washing, and they have a high boiling point and are difficult to remove. Therefore, it is not preferred that the usage amount thereof exceeds 300% by mass relative to the total mass of the polyhydroxy resin.

[0076] As the basic compound used for the production of the polyfunctional vinyl resin of the present invention, organic base compounds, alkali metal hydroxides, carbonates, etc. are preferred. As specific examples, triethylamine, diisopropylethylamine, pyridine, dimethylaminopyridine, sodium hydroxide, potassium hydroxide, potassium carbonate, and sodium carbonate can be mentioned, and triethylamine, pyridine, dimethylaminopyridine, sodium hydroxide, and potassium hydroxide are preferred.

[0077] The vinyl group-containing acyl halide or acid anhydride reacts with the phenolic hydroxyl group to generate an equimolar amount of acidic substances, which hinders the progress of the reaction. Therefore, a basic compound can be used for neutralization.

[0078] Regarding the amount of the basic compound used, it is usually 1.0 to 2.5 moles, preferably 1.0 to 1.8 moles, and more preferably 1.0 to 1.5 moles relative to 1 mole of the phenolic hydroxyl group of the polyhydric hydroxyl resin.

[0079] The reaction temperature for the production of the polyfunctional vinyl resin of the present invention is usually 15 to 150 °C, preferably 35 to 120 °C. In addition, in order to obtain a higher purity polyfunctional vinyl resin, it is preferable to raise the reaction temperature in two or more stages. For example, it is particularly preferable that the first stage is 15 to 50 °C and the second stage is 45 to 120 °C.

[0080] The reaction time for the production of the polyfunctional vinyl resin of the present invention is usually 0.5 to 10 hours, preferably 1 to 8 hours, and particularly preferably 1 to 5 hours. By having a reaction time of 0.5 hours or more, the reaction proceeds sufficiently, and by being 10 hours or less, the amount of by-products generated can be suppressed to a low level.

[0081] In the case where self-polymerization of an acid anhydride or acyl halide containing a vinyl group is a concern, polymerization inhibitors such as quinones, nitro compounds, nitrophenols, nitroso compounds, nitrone compounds, phenols, and oxygen can be used.

[0082] After the reaction is completed, the solvent is distilled off under heating and reduced pressure or directly dissolved in a solvent such as a ketone solvent having 4 to 7 carbon atoms (for example, methyl isobutyl ketone, methyl ethyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, etc.), an aromatic hydrocarbon such as benzene, toluene, xylene, or an ether such as cyclopentyl methyl ether, and water having low solubility in the target product, a lower alcohol such as methanol, or a mixed solvent thereof is added for washing, whereby by-products salts and impurities can be removed.

[0083] General vinyl resins are unstable under heating conditions, but the polyfunctional vinyl resin of the present invention has high stability, can distill off the solvent under heating conditions, and can remove volatile impurities. Therefore, it can be stably stored as a solid. The softening point is preferably 50 to 120 °C, and more preferably 70 to 100 °C.

[0084] In order to make the obtained vinyl resin as a reaction product into a solid, as the heating conditions for solvent distillation and impurity removal, 100 °C to 180 °C is preferable, and 120 °C to 160 °C is more preferable. When the temperature is lower than this range, the resin viscosity increases, so the acid generated from the acid anhydride or acyl halide tends to remain. In addition, when the temperature is higher than this range, the possibility of gelation of the polyfunctional vinyl resin increases. In addition, the distillation of the solvent and the removal of volatile impurities are preferably carried out under reduced pressure.

[0085] Regarding the production of the polyfunctional vinyl resin of the present invention, it is usually carried out while blowing an inert gas such as nitrogen into the system (in the gas or in the liquid). By carrying out the reaction while blowing the inert gas into the system, the resulting product can be prevented from coloring.

[0086] The blowing amount of the inert gas per unit time varies depending on the volume of the kettle used in this reaction. Preferably, for example, the blowing amount of the inert gas per unit time is adjusted in such a way that the volume of the kettle can be replaced in 0.5 to 20 hours.

[0087] The polyfunctional vinyl resin of the present invention can be cured alone, and is also preferably used as a polyfunctional resin composition containing various additives. For example, in order to promote curing, a radical polymerization initiator can be added for curing.

[0088] As the radical polymerization initiator (also referred to as a radical polymerization catalyst.), for example, as described later, by means such as heating to cause a crosslinking reaction to cure the resin composition of the present invention. In order to lower the reaction temperature at this time or to promote the crosslinking reaction of the unsaturated groups, a radical polymerization initiator can also be contained and used. The amount of the radical polymerization initiator used for this purpose is preferably 0.01 to 12 parts by mass, more preferably 0.1 to 8 parts by mass, relative to 100 parts by mass of the polyfunctional vinyl resin. Since the radical polymerization initiator is a radical polymerization catalyst, hereinafter it will be represented by the radical polymerization initiator.

[0089] If representative examples of the radical polymerization initiator are listed, there are peroxides such as benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hex-3-yne, di-tert-butyl peroxide, tert-butyl cumyl peroxide, α,α'-bis(tert-butylperoxy-m-isopropyl)benzene, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, dicumyl peroxide, di-tert-butyl peroxyisophthalate, tert-butyl peroxybenzoate, 2,2-bis(tert-butylperoxy)butane, 2,2-bis(tert-butylperoxy)octane, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, bis(trimethylsilyl) peroxide, trimethylsilyl triphenylsilyl peroxide, etc., but are not limited to these. In addition, although not a peroxide, 2,3-dimethyl-2,3-diphenylbutane can also be used as a radical polymerization initiator (or polymerization catalyst). However, the catalysts and radical polymerization initiators used in the curing of this resin composition are not limited to these examples.

[0090] As long as the effects are not hindered, the polyfunctional vinyl resin of the present invention can be blended with vinyl resins other than itself and other thermosetting resins. For example, vinyl ester resins, polyvinylbenzyl resins, polyallyl resins, epoxy resins, oxetane resins, maleimide resins, acrylate resins, polyester resins, polyurethane resins, polycyanate resins, phenolic resins, benzoxazine resins, etc. can be cited.

[0091] However, relative to the total amount of the resins, it is preferable to contain 20 parts by weight or more, more preferably 30 parts by weight or more, and still more preferably 50 parts by weight or more of the polyfunctional vinyl resin of the present invention.

[0092] It is also possible to blend thermoplastic resins such as polystyrene resin, polyphenylene ether resin, polyetherimide resin, polyethersulfone resin, PPS resin, polycyclopentadiene resin, polycycloolefin resin, and thermoplastic elastomers such as styrene-ethylene-propylene copolymer, styrene-ethylene-butene copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, hydrogenated styrene-butadiene copolymer, hydrogenated styrene-isoprene copolymer, and rubber-like substances such as polybutadiene and polyisoprene.

[0093] In the case where the vinyl resin to be blended is one or more vinyl compound classes having one or more polymerizable unsaturated hydrocarbon groups in the molecule, the type thereof is not particularly limited. That is, the vinyl compound classes only need to be compounds capable of forming crosslinks and curing by reacting with the polyfunctional vinyl resin of the present invention. More preferably, the polymerizable unsaturated hydrocarbon group is a carbon-carbon unsaturated double bond, and more preferably, the compound has two or more carbon-carbon unsaturated double bonds in the molecule.

[0094] The average number of carbon-carbon unsaturated double bonds per molecule of the vinyl compound class as the curable resin (the number of vinyl groups (including substituted vinyl groups). Also referred to as the terminal double bond number.) varies depending on the Mw of the vinyl compound class. For example, it is preferably 1 to 20, more preferably 2 to 18. If the terminal double bond number is too small, there is a tendency that it is difficult to obtain sufficient heat resistance as a cured product. In addition, if the terminal double bond number is too large, the reactivity increases excessively, and for example, adverse situations such as a decrease in the storage stability of the composition or a decrease in the fluidity of the composition may occur.

[0095] As vinyl compounds, for example, triallyl isocyanurate (TAIC) and other triallyl isocyanurate compounds, modified polyphenylene ether (PPE) modified with (meth)acryloyl or styryl at the terminal, polyfunctional (meth)acrylate compounds having two or more (meth)acryloyl groups in the molecule, vinyl compounds having two or more vinyl groups in the molecule such as polybutadiene (polyfunctional vinyl compounds), and vinylbenzyl compounds such as styrene and divinylbenzene can be cited. Among them, compounds having two or more carbon-carbon double bonds in the molecule are preferred. Specifically, TAIC, polyfunctional (meth)acrylate compounds, modified PPE resins, polyfunctional vinyl compounds, and divinylbenzene compounds can be cited. If these are used, it is considered that crosslinking is more suitably formed by a curing reaction, and the heat resistance of the cured product of the resin composition can be further improved. These can be used alone or in combination of two or more. A compound having one carbon-carbon unsaturated double bond in the molecule can be used in combination. As the compound having one carbon-carbon unsaturated double bond in the molecule, compounds having one vinyl group in the molecule (monovinyl compounds) can be cited.

[0096] In the polyfunctional vinyl resin composition of the present invention, in order to improve the flame retardancy of the obtained cured product, various known flame retardants can be used within the range not reducing the reliability. As the flame retardants that can be used, for example, halogen-based flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, silicone-based flame retardants, inorganic-based flame retardants, and organic metal salt-based flame retardants can be cited. From the viewpoint of the environment, halogen-free flame retardants are preferred, and phosphorus-based flame retardants are particularly preferred. These flame retardants can be used alone, or two or more flame retardants of the same series can be used in combination, or flame retardants of different series can be combined and used.

[0097] In the polyfunctional vinyl resin composition of the present invention, in order to further improve its functionality, components other than the above-listed components (sometimes referred to as "other components" in the present invention) can be included. As such other components, filler materials, ultraviolet ray preventives, antioxidants, coupling agents, plasticizers, solders, thixotropy imparting agents, smoothing agents, colorants, pigments, dispersants, emulsifiers, low elasticizing agents, mold release agents, defoaming agents, ion trappers, etc. can be cited.

[0098] Examples of the filler include inorganic fillers such as fused silica, crystalline silica, alumina, silicon nitride, boron nitride, aluminum nitride, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, boehmite, talc, mica, clay, calcium carbonate, magnesium carbonate, barium carbonate, zinc oxide, titanium oxide, magnesium oxide, magnesium silicate, calcium silicate, zirconium silicate, barium sulfate, and carbon; fibrous fillers such as carbon fiber, glass fiber, alumina fiber, silica-alumina fiber, silicon carbide fiber, polyester fiber, polyamide fiber, cellulose fiber, aramid fiber, and ceramic fiber; and particulate rubber, etc.

[0099] Examples of the other components include organic pigments such as quinacridone-based, azo-based, and phthalocyanine-based pigments; inorganic pigments such as titanium oxide, metal foil pigments, and rust-preventive pigments; ultraviolet absorbers such as hindered amine-based, benzotriazole-based, and benzophenone-based ultraviolet absorbers; antioxidants such as hindered phenol-based, phosphorus-based, sulfur-based, and hydrazide-based antioxidants; mold release agents such as stearic acid, palmitic acid, zinc stearate, and calcium stearate; leveling agents, rheology control agents, pigment dispersants, anti-shrinking agents, defoaming agents, and other additives. The blending amount of these other components is preferably in the range of 0.01 to 20% by mass based on all the solid components in the resin composition.

[0100] The multifunctional vinyl resin composition of the present invention can be made into a resin varnish by dissolving it in a solvent. Examples of the solvent include methyl ethyl ketone, acetone, toluene, xylene, tetrahydrofuran, dioxolane, dimethylformamide, methyl isobutyl ketone, methoxypropanol, cyclohexanone, methyl cellosolve, ethyl diglycol acetate, propylene glycol monomethyl ether acetate, γ-butyrolactone, etc. The selection and appropriate usage amount can be appropriately selected according to the use. For example, in the use of printed wiring boards, solvents having a boiling point of 160°C or lower such as methyl ethyl ketone, acetone, toluene, xylene, and 1-methoxy-2-propanol are preferred, and it is also preferred to use them in a proportion such that the non-volatile component is 20 to 80% by mass. On the other hand, in the use of build-up adhesive films, for example, ketones such as acetone, methyl ethyl ketone, and cyclohexanone; ester compounds such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, carbitol acetate, and γ-butyrolactone; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. are preferably used, and it is preferred to use them in a proportion such that the non-volatile component is 20 to 80% by mass. The laminate of the present invention is obtained by curing the resin varnish. Specifically, printed wiring boards, printed circuit boards, flexible printed wiring boards, build-up wiring boards, etc. can be cited.

[0101] The cured product obtained by curing the multi-functional vinyl resin composition of the present invention can be used as a molded article, a laminate, a cast product, an adhesive, a coating film, or a film. For example, the cured product of a semiconductor sealing material is a cast product or a molded article. As a method for obtaining the cured product for this use, the compound can be molded using a casting or transfer molding machine, an injection molding machine, etc., and then heated at 80 to 230 °C for 0.5 to 10 hours to obtain a cured product. In addition, the cured product of a resin varnish is a laminate. As a method for obtaining this cured product, the resin varnish can be impregnated into a base material such as the above-mentioned fibrous filler or paper, heated and dried to obtain a prepreg, and the prepregs can be laminated with each other alone or laminated with a metal foil such as a copper foil, and then hot-pressed to obtain the cured product. The uncured sheet or partially cured sheet of the multi-functional vinyl resin composition of the present invention can be suitably used as, for example, an interlayer film, a bonding sheet, a cover sheet, a bump sheet for a flip chip bonder, an insulating layer for a substrate, or a bonding layer.

[0102] By incorporating an inorganic high-dielectric powder such as barium titanate or an inorganic magnet such as ferrite, it can be used as a material for electronic components, particularly a material for high-frequency electronic components.

[0103] Next, the prepreg and its cured product of the present invention will be described. In the prepreg of the present invention, a base material is added to improve mechanical strength and increase dimensional stability.

[0104] As such a base material, various glass cloths such as untwisted gauze, cloth, chopped strand mat, and surface mat, asbestos cloth, metal fiber cloth, and other synthetic or natural inorganic fiber cloths, woven or non-woven fabrics made of liquid crystal fibers such as wholly aromatic polyamide fiber, wholly aromatic polyester fiber, and polybenzoxazole fiber, woven or non-woven fabrics made of synthetic fibers such as polyvinyl alcohol fiber, polyester fiber, and acrylonitrile fiber (non-woven·BR>Z), natural fiber cloths such as cotton cloth, linen cloth, and felt, carbon fiber cloth, kraft paper, cotton paper, natural cellulose-based cloths such as paper-glass mixed fiber paper, etc., are each used alone or two or more of them are used in combination.

[0105] Regarding the proportion of the base material, in the prepreg, it can be 5 to 90% by mass, preferably 10 to 80% by mass, and more preferably 20 to 70% by mass. If the base material ratio is less than 5% by mass, the dimensional stability and strength of the cured product tend to decrease. In addition, if the base material ratio is more than 90% by mass, the dielectric properties of the cured product tend to decrease.

[0106] In the prepreg of the present invention, if necessary, a coupling agent can be used to improve the adhesion at the interface between the resin and the base material. As the coupling agent, general coupling agents such as silane coupling agents, titanate coupling agents, aluminum-based coupling agents, and zirconium aluminate coupling agents can be used.

[0107] As a method for producing the prepreg of the present invention, for example, the following method can be cited: The polyfunctional vinyl resin composition of the present invention and other components as needed are uniformly dissolved or dispersed in the above-mentioned aromatic, ketone-based solvents, or a mixed solvent thereof, impregnated into a substrate, and then dried. The impregnation is carried out by dipping (immersion), coating, etc. Regarding the impregnation, it can be repeated several times as needed. In addition, at this time, it is also possible to repeatedly impregnate with multiple solutions having different compositions and concentrations to adjust to the finally desired resin composition and resin amount.

[0108] By curing the prepreg of the present invention by means of heating or the like, a cured product is obtained. There is no particular limitation on its manufacturing method. For example, multiple prepregs can be overlapped, and while bonding the layers under heating and pressure, thermal curing is carried out to obtain a cured product (laminated board) with the required thickness. It is also possible to combine a once-bonded and cured cured product with a prepreg to obtain a multi-layer laminate with a new layer structure. The lamination molding and curing are usually carried out simultaneously by hot pressing or the like, or the two can be carried out separately. That is, by performing heat treatment on the uncured or semi-cured prepreg obtained by pre-lamination molding or by using another method for treatment, it can be cured.

[0109] The molding and curing can be carried out, for example, in the range of temperature: 80 to 300 °C, pressure: 0.1 to 1000 kgf / cm 2 , time: 1 minute to 10 hours. More preferably, it is carried out in the range of temperature: 150 to 250 °C, pressure: 1 to 500 kgf / cm 2 , time: 1 minute to 5 hours.

[0110] The laminate of the present invention refers to a laminate composed of a layer of the prepreg of the present invention and a layer of a metal foil. As the metal foil used herein, for example, copper foil, aluminum foil, etc. can be cited. There is no particular limitation on its thickness, and it is in the range of 3 to 200 μm, more preferably in the range of 3 to 105 μm.

[0111] As a method for producing the laminate of the present invention, for example, the following method can be cited: The prepreg obtained from the polyfunctional vinyl resin composition of the present invention and a substrate described above and the metal foil are laminated in a layer structure corresponding to the purpose, and while bonding the layers under heating and pressure, thermal curing is carried out. In the laminate of the polyfunctional vinyl resin composition of the present invention, the cured product and the metal foil are laminated in an arbitrary layer structure. The metal foil can be used as the surface layer or as the intermediate layer. In addition to the above, it is also possible to repeat the lamination and curing multiple times to make it multi-layered.

[0112] In the adhesion to a metal foil, an adhesive can also be used. Examples of the adhesive include epoxy-based, acrylic-based, phenolic-based, cyanoacrylate-based adhesives, etc., but are not particularly limited to these. The above-mentioned lamination and curing can be carried out under the same conditions as those for the production of the cured product of the prepreg of the present invention.

[0113] The multifunctional vinyl resin composition of the present invention can also be formed into a film shape. There is no particular limitation on its thickness, which is in the range of 3 to 200 μm, and more preferably in the range of 5 to 105 μm.

[0114] As a method for manufacturing the film of the present invention, there is no particular limitation. For example, there can be mentioned a method of uniformly dissolving or dispersing the multifunctional vinyl resin composition and other components used as required in a solvent such as an aromatic-based or ketone-based solvent, or a mixed solvent thereof, coating it on a resin film such as a PET film, and then drying it. The coating can be repeated several times as required. In addition, at this time, multiple solutions with different compositions and concentrations can also be used for repeated coating to adjust to the finally desired resin composition and resin amount.

[0115] When using the resin sheet of the present invention as a bonding sheet, for example, two substrates can be bonded with the resin sheet. Each of the two substrates is, for example, a laminated board or a printed wiring board. Specifically, for example, the multifunctional vinyl resin composition is formed into a sheet shape on a support film by a coating method or the like and then heated, and the resin sheet is produced by drying or semi-curing it. The resin sheet is overlapped on a substrate (the first substrate), the support film is peeled off from the resin sheet, and another substrate (the second substrate) is overlapped. That is, the first substrate, the resin sheet (multifunctional vinyl resin composition), and the second substrate are laminated in sequence. Then, by heating and curing, the first substrate and the second substrate are bonded via the cured product of the multifunctional vinyl resin composition.

[0116] From the multifunctional vinyl resin composition of the present invention and a metal foil, a resin-coated metal foil can be obtained. Examples of the metal foil used herein include copper foil, aluminum foil, etc. There is no particular limitation on its thickness, which is in the range of 3 to 200 μm, and more preferably in the range of 5 to 105 μm.

[0117] As a method for manufacturing the resin-coated metal foil, there is no particular limitation. For example, there can be mentioned a method of uniformly dissolving or dispersing the multifunctional vinyl resin composition and other components used as required in a solvent such as an aromatic-based or ketone-based solvent, or a mixed solvent thereof, coating it on the metal foil, and then drying it. The coating can be repeated several times as required. In addition, at this time, multiple solutions with different compositions and concentrations can also be used for repeated coating to adjust to the finally desired resin composition and resin amount.

[0118] The substrate for electronic materials is formed using the laminate of the present invention. The above-mentioned substrate for electronic materials can be suitably used as components for various electrical and electronic devices such as mobile phones, PHS, notebook personal computers, PDAs (portable information terminals), portable video phones, personal computers, supercomputers, servers, routers, liquid crystal projectors, engineering workstations (EWS), pagers, word processors, televisions, video recorders of the viewfinder type or the monitor direct view type, electronic notebooks, electronic desktop computers, car navigation devices, POS terminals, devices including touch panels, etc., which require reliability in an environment where heat resistance and water resistance are needed and transmission reliability of high-frequency signals. In particular, due to the excellent heat stability of the dielectric properties of the cured product of the present invention, the dimensional stability corresponding to the formation of fine pattern circuits, and the moldability, it can be suitably used as a circuit substrate for the above-mentioned electrical and electronic devices. Specifically, single-sided, double-sided, multilayer printed circuit boards, flexible substrates, and build-up substrates can be cited. A multilayer circuit board using a metal plating as the above-mentioned conductor layer is also included as a preferred example.

[0119] Examples

[0120] Examples and comparative examples are cited to specifically illustrate the present invention, but the present invention is not limited to these examples. Unless otherwise specified, "parts" means parts by mass, and "%" means mass%. In addition, regarding the measurement methods, the following methods are respectively used for measurement.

[0121] The test conditions of the polyhydric hydroxyl resin, polyfunctional vinyl resin, and cured product are shown.

[0122] (1) Hydroxyl equivalent:

[0123] It is measured according to the JIS K0070 standard, and the unit is expressed as "g / eq.". Unless otherwise specified, the hydroxyl equivalent of the polyhydric hydroxyl resin means the phenolic hydroxyl equivalent.

[0124] (2) Softening point:

[0125] It is measured according to the JIS K7234 standard, ring and ball method. Specifically, an automatic softening point device (manufactured by Meitech Co., Ltd., ASP-MG4) is used.

[0126] (3) Vinyl equivalent:

[0127] It is measured according to the JIS K0070 standard. Specifically, the sample is reacted with Wijs solution (iodine monochloride solution), placed in the dark, and then the excess iodine chloride is reduced to iodine, and the iodine component is titrated with sodium thiosulfate to calculate the iodine value. The iodine value is converted to the vinyl equivalent.

[0128] (4) Relative dielectric constant and dielectric loss tangent:

[0129] Measured according to IPC-TM-650 2.5.5.9. Specifically, it is evaluated by using a material analyzer (manufactured by AGILENT Technologies) and obtaining the relative permittivity and dielectric loss tangent at a frequency of 1 GHz by volumetric method.

[0130] (5) Glass transition temperature (Tg):

[0131] Measured according to JIS C6481 standard. Specifically, it is represented by the peak of tanδ when measured with a dynamic viscoelasticity measuring device (manufactured by Hitachi High-Technologies Corporation, EXSTAR DMS6100) under the condition of temperature increase at 5 °C / minute.

[0132] (6) GPC (gel permeation chromatography) measurement:

[0133] Use a device with columns (manufactured by Tosoh Corporation, TSKgel G4000HXL, TSKgel G3000HXL, TSKgel G2000HXL) connected in series to the main body (manufactured by Tosoh Corporation, HLC-8220GPC), and set the column temperature to 40 °C. As the eluent, use tetrahydrofuran (THF), set the flow rate to 1 mL / minute, and use a differential refractive index detector as the detector. The measurement sample uses 50 μL of a substance obtained by dissolving 0.1 g of the sample in 10 mL of THF and filtering with a microfilter. Mw and Mn are obtained by conversion using a calibration curve obtained with standard polystyrene (manufactured by Tosoh Corporation, PStQuick Kit-H). Data processing uses the GPC-8020 model II version 6.00 manufactured by Tosoh Corporation.

[0134] (7) IR:

[0135] Use a Fourier transform infrared spectrophotometer (manufactured by Perkin Elmer Precisely, SpectrumOne FT-IR Spectrometer 1760X), use diamond ATR, coat the sample dissolved in toluene on the ATR, dry it, and then measure the absorbance at a wavenumber of 650 - 4000 cm -1 -1.

[0136] The abbreviations used in the examples and comparative examples are as follows.

[0137] [Aromatic hydroxy compound]

[0138] P1: Aromatic polyhydroxy compound obtained in Synthesis Example 1

[0139] P2: Aromatic polyhydroxy compound obtained in Synthesis Example 2

[0140] [Multifunctional vinyl resin, vinyl compound]

[0141] V1: The multifunctional vinyl resin obtained in Example 1

[0142] V2: The multifunctional vinyl resin obtained in Example 2

[0143] VH1: Multifunctional vinyl resin (PPE resin modified with vinyl benzyl ether at the end, manufactured by Mitsubishi Gas Chemical Company, Inc., OPE-2ST, Mn1187)

[0144] VH2: Multifunctional vinyl resin (PPE resin modified with methacryloyl at the end, manufactured by SABIC Japan Co., Ltd., SA9000, Mw1600)

[0145] PO: Organic peroxide (manufactured by NOF Corporation, Perbutyl P)

[0146] AO: Antioxidant (manufactured by ADEKA Corporation, ADK STAB AO-60)

[0147] Synthesis Example 1

[0148] In a reaction apparatus comprising a glass separable flask equipped with a stirrer, a thermometer, a nitrogen inlet tube, a dropping funnel, and a condenser, 500 parts of 2,6-dimethylphenol (the following structural formula) was charged,

[0149]

[0150] 7.3 parts of 47% BF3 ether complex was added, and the mixture was heated to 100 °C while stirring. While maintaining this temperature, 67.6 parts of dicyclopentadiene (the following structural formula) (0.12 times the molar amount relative to 2,6-dimethylphenol) was added dropwise over 1 hour.

[0151]

[0152] Furthermore, the reaction was carried out at a temperature of 115 - 125 °C for 4 hours, and 11 parts of calcium hydroxide was added. Further, 19 parts of a 10% aqueous oxalic acid solution was added. Then, the mixture was heated to 160 °C, dehydrated, and then heated to 200 °C under a reduced pressure of 5 mmHg to evaporate unreacted raw materials. 1320 parts of methyl isobutyl ketone (MIBK) was added to dissolve the product, 400 parts of warm water at 80 °C was added, and the mixture was washed with water, and the lower-layer aqueous layer was separated and removed. Then, the mixture was heated to 160 °C under a reduced pressure of 5 mmHg to evaporate MIBK, and 164 parts of a reddish-brown aromatic polyhydroxy compound (P1) was obtained.

[0153] The hydroxyl equivalent of the obtained aromatic polyhydroxy compound (P1) was 195, and the softening point was 73°C. The Mw obtained by GPC was 470, the Mn was 440, the content of the n = 1 body was 86.2 area%, and the content of n = 2 bodies or more was 11.0 area%.

[0154] Synthesis Example 2

[0155] In the same reaction apparatus as in Synthesis Example 1, 400 parts of phenol and 7.5 parts of 47% BF3 ether complex were charged, and the mixture was heated to 70°C with stirring. While maintaining this temperature, 70.2 parts (0.12 times the molar amount relative to phenol) of dicyclopentadiene were added dropwise over 2 hours. Further, the reaction was carried out at a temperature of 125 to 135°C for 4 hours, and 11.7 parts of calcium hydroxide were added. Further, 20 parts of a 10% aqueous oxalic acid solution were added. Then, it was heated to 160°C, dehydrated, and then heated to 200°C under a reduced pressure of 5 mmHg to evaporate unreacted raw materials. 1100 parts of MIBK were added to dissolve the product, 330 parts of warm water at 80°C were added, and it was washed with water, and the lower-layer water tank was separated and removed. Then, it was heated to 160°C under a reduced pressure of 5 mmHg to evaporate MIBK, and 158 parts of a reddish-brown aromatic polyhydroxy compound (P2) were obtained.

[0156] The hydroxyl equivalent of the obtained aromatic polyhydroxy compound (P2) was 177, and the softening point was 92°C. The Mw obtained by GPC was 450, the Mn was 390, the content of the n = 1 body was 67.5 area%, and the content of n = 2 bodies or more was 32.5 area%.

[0157] Example 1

[0158] In the same apparatus as in Synthesis Example 1, 100 parts of polyhydroxy resin (P1), 42.6 parts of pyridine (1.05 equivalents relative to the hydroxyl equivalent of P1), 3.1 parts of dimethylaminopyridine (0.05 equivalents relative to the hydroxyl equivalent of P1), and 200 parts of toluene were charged, and the temperature was raised to 80°C to dissolve. After cooling to 20°C, 94.9 parts (1.2 equivalents relative to the hydroxyl equivalent of P1) of methacrylic anhydride (the following structural formula) were added dropwise over 30 minutes,

[0159]

[0160] Furthermore, the reaction was carried out at 115°C for 3 hours. The obtained resin was dissolved in 360 parts of toluene and washed with 241 parts of methanol water with a methanol concentration of 30%. Then, the solvent was distilled off under reduced pressure at 150°C under a reduced pressure of 5 mmHg to obtain 130 parts of a solid polyfunctional vinyl resin (V1).

[0161] The hydroxyl equivalent of the obtained polyfunctional vinyl resin (V1) is 25,000, the vinyl equivalent is 290, and the softening point is 86 °C. It is a polyfunctional vinyl resin represented by formula (1), R1 is methyl, i is 2, the Mw obtained by GPC is 650, the Mn is 550, the content of the n = 1 body is 78.9 area%, and the content of n = 2 bodies or more is 19.4 area%.

[0162] The GPC of the polyfunctional vinyl resin (V1) is shown in Figure 1 , and the IR diagram is shown in Figure 2 .

[0163] Example 2

[0164] In the same apparatus as in Synthesis Example 1, 100 parts of a polyhydric hydroxyl resin (P1), 42.6 parts of pyridine (1.05 equivalents relative to the hydroxyl equivalent of P1), 3.1 parts of dimethylaminopyridine (0.05 equivalents relative to the hydroxyl equivalent of P1), and 200 parts of toluene were charged, heated to 80 °C, and dissolved. After cooling to 20 °C, 64.3 parts of methacryloyl chloride (the following structural formula) (1.2 equivalents relative to the hydroxyl equivalent of P1) was added dropwise over 30 minutes,

[0165]

[0166] Furthermore, the reaction was carried out at 115 °C for 3 hours. The obtained resin was dissolved in 290 parts of toluene and washed with 211 parts of methanol water with a methanol concentration of 30%. Then, the solvent was distilled off under reduced pressure at 5 mmHg and 150 °C to obtain 130 parts of a solid polyfunctional vinyl resin (V2).

[0167] The hydroxyl equivalent of the obtained polyfunctional vinyl resin (V2) is 22,000, the vinyl equivalent is 295, and the softening point is 87 °C. It is a polyfunctional vinyl resin represented by formula (1), R1 is methyl, i is 2, the Mw obtained by GPC is 640, the Mn is 540, the content of the n = 1 body is 79.6 area%, and the content of n = 2 bodies or more is 18.4 area%.

[0168] Comparative Example 1

[0169] In the same apparatus as in Synthesis Example 1, 100 parts of a polyhydric hydroxyl resin (P2), 46.9 parts of pyridine (1.05 equivalents relative to the hydroxyl equivalent of P2), 3.5 parts of dimethylaminopyridine (0.05 equivalents relative to the hydroxyl equivalent of P2), and 200 parts of toluene were charged, heated to 80 °C, and dissolved. After cooling to 20 °C, 104.5 parts of methacrylic anhydride (1.2 equivalents relative to the hydroxyl equivalent of P2) were added dropwise over 30 minutes, and the mixture was further reacted at 115 °C for 3 hours. The resulting resin was dissolved in 390 parts of toluene and washed with 254 parts of methanol-water having a methanol concentration of 30%. Then, the solvent was distilled off under reduced pressure at 5 mmHg and heated to 150 °C, and as a result, a polymerization reaction occurred and the target vinyl resin was not obtained.

[0170] Examples 3 to 6, Comparative Examples 2 to 5

[0171] They were mixed in the blending ratios (parts) shown in Table 1, dissolved in toluene, and a homogeneous vinyl resin composition varnish having a nonvolatile content of 50% was obtained. The obtained vinyl resin composition varnish was coated on a PET film, dried at 130 °C for 5 minutes, peeled off from the PET film, and a resin composition was obtained. The resin composition was sandwiched between mirror plates, cured under reduced pressure at 130 °C for 30 minutes, and further cured at 220 °C while applying a pressure of 2 MPa for 100 minutes to obtain a cured product. The measurement results of the relative dielectric constant, dielectric loss tangent, and Tg of the obtained cured product are shown in Table 1.

[0172] [Table 1]

[0173]

[0174] Compared with the comparative examples, the polyfunctional vinyl resin of the examples has good storage stability and exhibits excellent physical properties such as a low dielectric constant and a low dielectric loss tangent.

[0175] Industrial Applicability

[0176] The polyfunctional vinyl resin of the present invention can be used as a dielectric material, an insulating material, and a heat-resistant material in fields such as the electrical and electronic industries and the aerospace industry. For example, it can be used as a printed circuit board, a sealing material, and a casting material for electronic devices, and particularly as a material with low signal loss for electronic components in high-speed communication devices.

Claims

1. A polyfunctional vinyl resin represented by the following general formula (1), wherein, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, X independently represents a hydrogen atom or a vinyl group-containing group represented by the above formula (1a), at least one is a vinyl group-containing group, R2 is a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms, i is an integer of 1 to 3, n represents the number of repetitions, and its average value is a number of 1 to 5.

2. A method for producing a polyfunctional vinyl resin, which is a method for producing the polyfunctional vinyl resin according to claim 1, characterized in that, Dicyclopentadiene is reacted at a ratio of 0.08 to 0.80 times the molar amount with respect to the substituted phenol represented by the following general formula (2) to obtain a polyhydroxy resin represented by the following general formula (3), and then the obtained polyhydroxy resin is reacted with one or more of an acid anhydride represented by the following general formula (4a) or an acyl halide represented by the following general formula (4b). Among them, R1 and i have the same meanings as defined in the above general formula (1), respectively. Among them, R1, i and n have the same meanings as defined in the above general formula (1), respectively. Among them, R3 has the same meaning as the definition of R2 in the above formula (1a), and R4 represents a halogen.

3. The method for producing a polyfunctional vinyl resin according to claim 2, wherein, For the obtained polyfunctional vinyl resin as a reactant, the solvent and volatile impurities are removed under reduced pressure in a temperature range of 100 to 180 °C to make it a solid.

4. A polyfunctional vinyl resin composition comprising, as essential components, the polyfunctional vinyl resin according to claim 1 and a radical polymerization initiator.

5. A cured product obtained by curing the polyfunctional vinyl resin composition according to claim 4.

6. A prepreg comprising the polyfunctional vinyl resin composition according to claim 4 or a semi-cured product thereof, and a fibrous substrate.

7. A resin sheet comprising a resin layer of the polyfunctional vinyl resin composition according to claim 4 or a semi-cured product thereof, and a support film.

8. A laminate formed by laminating and molding the prepreg according to claim 6 and / or the resin sheet according to claim 7.

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