Fluorine-containing epoxy resin for electrical materials and method for producing the same

Abstract

Provided is a fluorine-containing epoxy resin for electrical materials, said fluorine-containing epoxy resin having a low dielectric constant, a low dielectric dissipation factor and a small coefficient of linear expansion. The fluorine-containing epoxy resin for electrical materials is characterized by being represented by formula (E) [where: n stands for an integer of 0 or more, and the average value of n is not more than 0.18; and M stands for a group represented by formula (E1), formula (E2) or formula (E3) (where Z represents hydrogen or a fluoroalkyl group having 2-10 carbon atoms)].

Description

Technical Field

[0001] The present disclosure relates to a fluorine-containing epoxy resin for electrical materials and a method for producing the same.

Background Art

[0002] Phenolic resins, epoxy resins, polyimide resins, etc. are used as laminating materials for multilayer printed wiring boards. However, with the high-speed arithmetic processing of computers, there is a strong demand to increase the signal propagation speed of multilayer printed wiring boards. In addition, in satellite communication and mobile radio, since high frequencies in the gigahertz (GHz) band are used, it is necessary that the printed wiring board material used for transceiver devices is excellent in terms of high-frequency transmission characteristics. In order to meet this requirement, materials with lower dielectric constant and dielectric loss tangent are desired compared to conventional materials such as epoxy resins and polyimide resins.

[0003] For example, Patent Document 1 describes a laminate obtained by laminating a prepreg obtained by impregnating a sheet-like base material with an impregnating varnish containing a fluorine-containing epoxy compound having a specific structure.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure provides a fluorine-containing epoxy resin for electrical materials having a low dielectric constant and a low dielectric loss tangent, and a small coefficient of linear expansion. The present disclosure also provides a novel method for producing a fluorine-containing epoxy resin.

Means for Solving the Problems

[0006] The present disclosure provides the following formula (E):

Chemical Formula

Chemical formula

Chemical formula

Chemical formula

[0007] The average value of the above n is preferably 0.09 to 0.18.

[0008] The above M is represented by the following formula (E2):

Chemical formula

[0009] The molar ratio (1,3-isomer / 1,4-isomer) of the 1,3-isomer and 1,4-isomer of the group represented by the above formula (E2) is preferably 0 / 100 to 100 / 0.

[0010] The fluorine-containing epoxy resin for electrical materials of the present disclosure may have a content of 0 to 10% by mass of a compound represented by the following formula (F):

Chemical formula

[0011] The fluorine-containing epoxy resin for electrical materials of the present disclosure is represented by the following formula (G): HO-M-OH (In the formula, M is the same as defined above), the content of the fluorine-containing diol represented thereby may be 0 to 10% by mass.

[0012] The present disclosure also provides the following formula (G): HO-M-OH (In the formula, M is the following formula (E1): [Chemical formula] a group represented by, the following formula (E2): [Chemical formula] a group represented by, or the following formula (E3): [Chemical formula] (In the formula, Z is hydrogen or a fluoroalkyl group having 2 to 10 carbon atoms.) A step of reacting a fluorine-containing diol represented by a compound having a double bond to obtain a fluorine-containing olefin having two double bonds, and a step of oxidizing the fluorine-containing olefin to obtain a fluorine-containing epoxy resin, and a method for producing a fluorine-containing epoxy resin characterized by comprising the steps.

[0013] The present disclosure further provides a curable composition containing the fluorine-containing epoxy resin for electrical materials or the fluorine-containing epoxy resin obtained by the above production method, and a curing agent. [Advantages of the Invention]

[0014] The fluorine-containing epoxy resin for electrical materials of the present disclosure has a low dielectric constant and a low dielectric tangent, and a small coefficient of linear expansion. The production method of the present disclosure can produce a specific fluorine-containing epoxy resin by a novel production method. [Embodiments for Carrying Out the Invention]

[0015] The fluorine-containing epoxy resin for electrical materials of the present disclosure is represented by the above formula (E). In the above formula (E), n is an integer of 0 or more, and the average value of n is 0.18 or less. By the average value of n being 0.18 or less, while having a low dielectric constant and a low dielectric tangent, the coefficient of linear expansion becomes low, which is particularly suitable for electrical material applications. The fluorine-containing epoxy resin for electrical materials of the present disclosure is particularly suitable for electrical material applications also in terms of excellent heat resistance, low water absorption and moisture absorption, and excellent mechanical properties. The present disclosure also relates to the use of the fluorine-containing epoxy resin for electrical materials of the present disclosure in electrical materials. The fluorine-containing epoxy resin for electrical materials of the present disclosure may optionally contain a compound represented by the following formula (F), a compound represented by the formula (G), a solvent, etc., or may be a composition containing the compound represented by the above formula (E).

[0016] The average value of the above n is preferably 0.18 or less, more preferably 0.16 or less. Further, from the viewpoints of the mechanical properties and adhesion of the cured product, the average value of n is preferably 0 or more, more preferably 0.01 or more, still more preferably 0.08 or more, even more preferably 0.09 or more, and particularly preferably 0.1 or more. Incidentally, the average value of the above n may be 0. The above n is a numerical value obtained by the area ratio of GPC (gel permeation chromatography). For example, when the area ratio of the compound with n = 0 to the total area of the compounds in the formula (E) is 0.93, the area ratio of the compound with n = 1 is 0.06, and the area ratio of the compound with n = 2 is 0.01, the average value of n is 0.08 (= 1 * 0.06 + 2 * 0.01). The GPC conditions are not limited, but for example, it can be measured using Shodex KF-801 and KF-802 as columns, each 30 cm, and chloroform as the developing solvent.

[0017] As the above M, a group represented by the formula (E1) or a group represented by the formula (E2) is preferable, and a group represented by the formula (E2) is more preferable.

[0018] M is a group represented by the above formula (E2), and the molar ratio (1,3-isomer / 1,4-isomer) of the 1,3-isomer and 1,4-isomer of the group represented by the formula (E2) is preferably 0 / 100 to 100 / 0. The molar ratio (1,3-isomer / 1,4-isomer) is more preferably 95 / 5 to 50 / 50, still more preferably 95 / 5 to 70 / 30, and particularly preferably 95 / 5 to 80 / 20. The 1,3-isomer and 1,4-isomer of the group represented by the formula (E2) have the structures shown below.

[0019] 1,3-isomer of the group represented by the formula (E2)

Chemical formula

[0020] 1,4-isomer of the group represented by the formula (E2)

Chemical formula

[0021] The fluorine-containing epoxy resin for electrical materials of the present disclosure preferably has an epoxy equivalent of 250 or more. More preferably, it is 260 or more, and still more preferably 265 or more. The above epoxy equivalent is preferably 310 or less, and more preferably 300 or less. The above epoxy equivalent is a value measured by the method of JIS K-7236.

[0022] The fluorine-containing epoxy resin for electrical materials of the present disclosure preferably has a glass transition temperature of 100 to 200°C. The above glass transition temperature is more preferably 110°C or higher, still more preferably 120°C or higher, and even more preferably 130°C or higher. Also, the glass transition temperature may be 150°C or lower. The above glass transition temperature is determined as the midpoint of the endothermic curve in the second run by heating (first run) - cooling - heating (second run) the temperature range from 30°C to 250°C at a rate of 10°C / min using a DSC (differential scanning calorimeter: SEIKO, RTG220).

[0023] The fluorine-containing epoxy resin for electrical materials of the present disclosure preferably has a linear expansion coefficient of 150 ppm or less. More preferably, the linear expansion coefficient is 100 ppm or less, still more preferably 70 ppm or less, even more preferably 60 ppm or less, particularly preferably 55 ppm or less, and most preferably 50 ppm or less. The lower limit of the linear expansion coefficient is not particularly limited, and may be, for example, 10 ppm or more. The above linear expansion coefficient is a value measured by thermomechanical analysis (TMA).

[0024] The fluorine-containing epoxy resin for electrical materials of the present disclosure preferably has a relative permittivity of 3.8 or less. More preferably, it is 3.4 or less, still more preferably 3.0 or less, and particularly preferably 2.6 or less. The lower limit of the relative permittivity is not limited, and may be, for example, 2.2 or more or 2.4 or more. The above relative permittivity is a value measured at 11 GHz by an automatic balance bridge (parallel plate capacitor method) conforming to JIS C 2138.

[0025] The fluorine-containing epoxy resin for electrical materials of the present disclosure preferably has a dielectric loss tangent of 0.05 or less. More preferably, it is 0.03 or less, still more preferably 0.02 or less, and particularly preferably 0.01 or less. The lower limit of the dielectric loss tangent is not limited, and may be, for example, 0.001 or more or 0.002 or more. The above dielectric loss tangent is a value measured at 11 GHz by an automatic balance bridge (parallel plate capacitor method) conforming to JIS C 2138.

[0026] The fluorine-containing epoxy resin for electrical materials of the present disclosure preferably has a refractive index of 1.40 to 1.50. More preferably, it is 1.45 or less, still more preferably 1.43 or less, and particularly preferably 1.42 or less. Also, it may be 1.41 or more or 1.42 or more. The above refractive index is a value measured by an Abbe refractometer.

[0027] The glass transition temperature, coefficient of linear expansion, relative permittivity, dielectric loss tangent, and refractive index are values obtained using a test piece prepared by adding 2 parts by mass of 2-ethyl-4-methylimidazole to 100 parts by mass of the fluorine-containing epoxy resin for electrical materials of the present disclosure, heating the mixture to 50°C and uniformly mixing it, and then curing the resulting curable composition at 200°C for 5 hours.

[0028] The fluorine-containing epoxy resin for electrical materials of the present disclosure has the following formula (F):

Chemical formula

[0029] The fluorine-containing epoxy resin for electrical materials of the present disclosure has the following formula (G): HO-M-OH (wherein M is the same as defined above). It is preferably 0 to 10% by mass, more preferably 0 to 5% by mass, still more preferably 0 to 3% by mass, and particularly preferably 0 to 2% by mass. The content of the fluorine-containing diol may be 0.01% by mass or more or 0.1% by mass or more. The fluorine-containing epoxy resin for electrical materials of the present disclosure can be produced using the compound represented by formula (G) as a raw material. In such a case, the compound represented by formula (G) as a raw material may remain in the fluorine-containing epoxy resin for electrical materials. The fluorine-containing epoxy resin for electrical materials of the present disclosure may contain the compound represented by formula (G) within the above range. When containing the compound represented by the above formula (G), the fluorine-containing epoxy resin for electrical materials of the present disclosure can also be referred to as a fluorine-containing epoxy resin for electrical materials represented by formula (E) and a composition containing the compound represented by formula (G).

[0030] Since the average value of n in formula (E) of the fluorine-containing epoxy resin for electrical materials of the present disclosure is 0.18 or less, it has a low dielectric constant and a low dielectric tangent, a small coefficient of linear expansion, excellent mechanical properties, and is particularly suitable as a material for electrical material applications (electronic material applications), especially as a low dielectric constant material. The present disclosure relates to the use of the above fluorine-containing epoxy resin as a low dielectric material. The electrical material applications using the fluorine-containing epoxy resin for electrical materials of the present disclosure are not particularly limited, but are also useful as printed circuit boards for high frequencies that require high frequency characteristics, that is, substrates for electronic devices such as antennas, radars, network routers, backplanes, wireless infrastructure, etc., and substrates for various automotive sensors and substrates for engine management sensors, and are particularly suitable for applications aimed at reducing transmission loss in the millimeter wave band. The present disclosure also relates to the use of the above fluorine-containing epoxy resin for printed circuit boards for high frequencies. In addition, the fluorine-containing epoxy resin for electrical materials of the present disclosure can be used in electronic materials such as pastes, B-stage films, copper foils with resin, or prepregs for printed circuit boards, particularly multilayer substrates compatible with high frequencies, insulating materials for build-up, etc.

[0031] The fluorine-containing epoxy resin for electrical materials of the present disclosure can be obtained, for example, by reacting a fluorine-containing diol represented by the following formula (G): HO-M-OH (wherein M is the same as defined above) with epichlorohydrin. For example, by controlling the reaction temperature or the reaction amount of epichlorohydrin, the average value of n in the above formula (E) can be adjusted to 0.18 or less. For example, it can be made 0.18 or less by using an excessive amount of epichlorohydrin. It is also possible to adjust the average value of n after the reaction. For example, methods such as separating the initial fraction by vacuum distillation, methods described in JP-A-2006-233078 of making it 0.18 or less using a poor solvent and a good solvent, and methods of efficiently making it 0.18 or less by dissolving in a solvent and then cooling and crystallizing can be mentioned.

[0032] The fluorine-containing epoxy resin for electrical materials of the present disclosure can also be obtained by a production method of a fluorine-containing epoxy resin, which includes a step of reacting a fluorine-containing diol represented by the following formula (G): HO-M-OH (wherein M is the same as defined above) with a compound having a double bond to obtain a fluorine-containing olefin having two double bonds, and a step of oxidizing the above fluorine-containing olefin to obtain a fluorine-containing epoxy resin. In this production method, a fluorine-containing epoxy resin in which n in the general formula (E) is 0 can be obtained.

[0033] The compound having a double bond may be any compound that has a double bond in its molecular structure and can react with the hydroxyl group of the fluorine-containing diol to obtain the above fluorine-containing olefin. For example, a compound represented by CH2=CH-R (wherein R is an organic group or a silyl group) is preferable. Examples of the above R include an alkyl group having 1 to 10 carbon atoms in which a part of the hydrogen atoms bonded to the carbon atoms are substituted with halogen atoms; a hydroxyalkyl group having 1 to 10 carbon atoms, a silylalkyl group having 1 to 10 carbon atoms, a silyl group, and the like. Specific examples of the compound having a double bond include allyl halides such as allyl chloride and allyl bromide; compounds such as allyl alcohol and allyl silane.

[0034] The step of obtaining the fluorine-containing olefin is not particularly limited as long as a compound having a hydroxyl group and a double bond of the fluorine-containing diol can react to obtain the fluorine-containing olefin, but it may be carried out at 20 to 80 °C, preferably at 30 to 60 °C.

[0035] In the step of oxidizing the fluorine-containing olefin to obtain a fluorine-containing epoxy resin, the oxidation can be carried out by reacting the fluorine-containing olefin with an oxidizing agent. Specifically, it can be carried out by adding an oxidizing agent to a reaction vessel filled with the fluorine-containing olefin.

[0036] The oxidizing agent is not particularly limited as long as it can oxidize the double bond of the fluorine-containing olefin to convert it into an epoxy group. For example, oxidizing agents such as hydrogen peroxide and peracetic acid can be used. The amount of the oxidizing agent used is preferably 2 to 5 moles, more preferably 2.1 to 3 moles, per 1 mole of the fluorine-containing olefin.

[0037] The oxidation of the fluorine-containing olefin is preferably carried out at 30 °C or higher, more preferably at 40 °C or higher. Also, it is preferably carried out at 80 °C or lower, more preferably at 70 °C or lower.

[0038] The present disclosure also provides a curable composition containing the fluorine-containing epoxy resin for electrical materials or the fluorine-containing epoxy resin obtained by the above production method, and a curing agent. The curable composition of the present disclosure is particularly suitable for electrical materials.

[0039] As the above-mentioned curing agent, a curing agent for epoxy resin is preferred.Examples of the curing agent for epoxy resins include 4,4'-diaminodicyclohexylmethane, 1,4-diaminocyclohexane, 2,6-diaminopyridine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 2,2'-bis(4-aminophenyl)propane, benzidine, 4,4'-diaminophenyloxide, 4,4'-diaminophenylsulfone, bis(4-aminophenyl)methylphosphine oxide, bis(4-aminophenyl)phenylphosphine oxide, bis(4-aminophenyl)methylamine, 1,5-diaminonaphthalene, m-xylylenediamine, 1,1'-bis(p-aminophenyl)furane, p-xylylenediamine, hexamethylenediamine, 6,6'-diamino-2,2'-dipyridyl, 4,4'-diaminobenzophenone, 4,4'-diaminoazobenzene, bis(4-aminophenyl)phenylmethane, 1,1-bis(4-aminophenyl)cyclohexane, 1,1-bis(4-amino-3-methylphenyl)cyclohexane, 2,5-bis(m-aminophenyl)-1,3,4-oxadiazole, 2,5-bis(p-aminophenyl)-1,3,4-oxadiazole, 2,5-bis(p-aminophenyl)-1,3,4-oxadiazole, 5,5-di(m-aminophenyl)-(2,2')bis(1,3,4-oxadiazolyl), 4,4'-diaminodiphenyl ether, 4,4'-bis(p-aminophenyl)-2,2'-dithiazole, m-bis(4-p-aminophenyl-2-thiazolyl)benzene, 4,4'-diaminobenzanilide, 4,4'-diaminophenylbenzoate, N,N'-bis(4-aminobenzyl)-p-phenylenediamine, 4,4'-methylenebis(2-dichloroaniline), benzoguanamine, methylguanamine, tetramethylbutanediamine, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bis(anhydrotrimellitate), glycerol tris(anhydrotrimellitate), maleic anhydride, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, boron trifluoride complex, etc. These can be used alone or in combination of two or more. The compounding amount of the curing agent for the epoxy resin is preferably 0.1 to 50 parts by mass with respect to 100 parts by mass of the fluorine-containing epoxy resin and, if necessary, the non-fluorine-containing epoxy resin.

[0040] Examples of the curing agent for the epoxy resin, which overlap with those described above, include polyamines, polycarboxylic acids, acid anhydrides, and phenols. In addition, imidazoles, polymercaptans, and organic acid hydrazides are included. Examples of the polyamine include diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, dimethylaminopropylamine, diethylaminopropylamine, dibutylaminopropylamine, hexamethylenediamine, N-aminoethylpiperazine, trimethylhexamethylenediamine, bis-(hexamethylene)triamine, polyoxypropylenediamine, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, 3-amino-1-cyclohexylaminopropane, 4,4'-diaminodicyclohexylmethane, isophoronediamine, 1,3-bis(aminomethyl)cyclohexane, a mixture of N-dimethylcyclohexylaminopropane and 4,4'-diaminodicyclohexylaminopropane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylether, diaminodiphenylsulfone, m-phenylenediamine, 2,4-toluylenediamine, 2,6-toluylenediamine, 2,3-toluylenediamine, 3,4-toluylenediamine, metaxylylenediamine, xylylenediamine, dicyandiamide, and diacetoneacrylamide. Examples of the polycarboxylic acid include phthalic acid, hydroxyisophthalic acid, succinic acid, sebacic acid, maleic acid, dodecenylsuccinic acid, chlorendic acid, pyromellitic acid, trimellitic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, and methylnadic acid. Examples of the acid anhydride include maleic anhydride, dodecenyl succinic anhydride, chlorendic anhydride, sebacic anhydride, phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, cyclopentane tetracarboxylic dianhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, tetramethylene maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, 5-(2,5-dioxotetrahydroxyfuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, and methyl nadic anhydride. Examples of the phenols include bisphenol A, bisphenol F, bisphenol S, bisphenol AD, hydroquinone, resorcinol, methylresorcinol, biphenol, tetramethylbiphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thiodiphenols, phenol novolak resin, cresol novolak resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpene phenol resin, dicyclopentadiene phenol resin, bisphenol A novolak resin, trisphenol methane type resin, naphthol novolak resin, brominated bisphenol A, brominated phenol novolak resin, and other various polyhydric phenols, and polyhydric phenol resins obtained by the condensation reaction of various phenols with various aldehydes such as benzaldehyde, hydroxybenzaldehyde, crotonaldehyde, and glyoxal, polyhydric phenol resins obtained by the condensation reaction of xylene resin with phenols, co-condensation resins of heavy oil or pitches with phenols and formaldehydes, phenol-benzaldehyde-xylylene dimethoxide polycondensate, phenol-benzaldehyde-xylylene dichloride polycondensate, phenol-benzaldehyde-4,4'-dimethoxide biphenyl polycondensate, phenol-benzaldehyde-4,4'-dichloride biphenyl polycondensate, and other various phenol resins.

[0041] The curing agent for the epoxy resin may be used alone or in combination of two or more. In one embodiment, the curable composition of the present disclosure preferably contains a curing agent for an epoxy resin in an equivalent ratio of the total of a fluorine-containing epoxy resin and a non-fluorine epoxy resin of 0.01 to 10 equivalents, more preferably 0.1 to 5 equivalents, and still more preferably 0.5 to 2 equivalents. Such an embodiment is preferable from the viewpoint of curability.

[0042] The curable composition of the present disclosure may contain a cationic or anionic polymerization initiator instead of or together with the curing agent. A cationic or anionic polymerization initiator is a compound that initiates and / or accelerates the curing reaction of the curable composition by heating or light. As the cationic polymerization initiator, any compound that generates cationic species such as Bronsted acid and Lewis acid by heating or light may be used. Examples thereof include onium salts, protonic acid esters, and Lewis acid-amine complexes. The cationic polymerization initiator may be used alone or in combination of two or more. As the anionic polymerization initiator, any compound that generates anionic species such as Bronsted base and Lewis base by heating or light may be used. Examples thereof include imidazoles and tertiary amines. The anionic polymerization initiator may be used alone or in combination of two or more.

[0043] The fluorine-containing epoxy resin for electrical materials of the present disclosure can be dissolved in a solvent and used as a paint for electrical materials such as varnish. In other words, the curable composition of the present disclosure preferably further contains a solvent. Also, the curable composition of the present disclosure is preferably a paint for electrical materials.

[0044] Examples of the solvent include toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, dimethylformamide, N-methylpyrrolidone, etc., and these can be used alone or in combination of two or more. The amount of the solvent in the curable composition of the present disclosure is usually 20 to 95% by mass.

[0045] The curable composition of the present disclosure may contain, as components other than the fluorine-containing epoxy resin, curing agent, and the above solvent for electrical materials of the present disclosure, commonly used non-fluorine-containing epoxy resins such as bisphenol A epoxy resin, brominated bisphenol A epoxy resin, novolac epoxy resin, epoxy curing agents, etc. Examples of the non-fluorine-containing epoxy resin include, although overlapping with the above, hydrogenated epoxy resin, alicyclic epoxy resin, or epoxy resin containing an isocyanurate ring, or bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, phenol aralkyl type epoxy resin, biphenyl aralkyl type epoxy resin, hydrogenated epoxy resin obtained by hydrogenating the aromatic ring of the above various epoxy resins, dicyclopentadiene type epoxy resin, and the like.

[0046] The amount of the non-fluorine-containing epoxy resin is preferably 90 parts by mass or less, more preferably 80 parts by mass or less, still more preferably 50 parts by mass or less, even more preferably 30 parts by mass or less, and particularly preferably 10 parts by mass or less with respect to 100 parts by mass of the fluorine-containing epoxy resin of the present disclosure.

[0047] The present disclosure also provides a coating film obtained by applying the curable composition of the present disclosure to a substrate. The coating method of the curable composition is not particularly limited, and examples thereof include spray coating, roll coating, coating with a doctor blade, dip (immersion) coating, impregnation coating, spin flow coating, curtain flow coating, etc. Among them, immersion and impregnation coating are preferred. After applying the curable composition of the present disclosure, the coating film may be dried or fired. The above drying is preferably carried out at a temperature of 70 to 300 °C for 5 to 60 minutes. The above firing is preferably carried out at a temperature of 260 to 410 °C for 10 to 30 minutes. The thickness of the above coating film is not limited and may be appropriately set according to the use. For example, it may be 1 to 1000 μm. The base material is not particularly limited and may be appropriately set according to the application. For example, base materials such as aluminum, SUS, copper, iron, polyimide, polyester, and polyamide can be used.

[0048] The curable composition of the present disclosure can be impregnated and coated on a sheet-like base material, for example, and dried at room temperature to 160 ° C. to obtain a prepreg without adhesiveness. The drying temperature is determined by the solvent and curing agent used. Next, stack the required number of the obtained prepregs and heat-cure at 100 to 250 ° C. under a pressure of 1 to 100 kgf / cm 2 to obtain a laminate. The number of laminations is not particularly limited, but when used for printed wiring boards, etc., it is usually 2 to 50 layers. The present disclosure also provides a printed wiring board including a prepreg obtained by impregnating and coating a sheet-like base material with the curable composition of the present disclosure. As the sheet-like base material, almost all those generally used for laminated materials can be used. The thickness of the sheet-like base material is not particularly limited, but is usually 0.03 to 10 mm, preferably 0.03 to 1 mm. Examples of the sheet-like base material include woven fabrics or non-woven fabrics made of inorganic fibers such as glass fibers and carbon fibers, and organic fibers such as Kevlar (aromatic polyamide manufactured by DuPont), or sheets of polytetrafluoroethylene porous bodies. Preferred sheet-like base materials include glass cloths made of various glass fibers such as E glass, C glass, A glass, S glass, D glass, YM-31-A glass, and Q glass using SiO2, Al2O3, etc. as components.

Examples

[0049] Next, the present disclosure will be described with reference to examples, but the present disclosure is not limited to such examples only.

[0050] Each numerical value in the examples was measured by the following method.

[0051] GPC measurement Using Shodex KF-801 and KF-802 each with a length of 30 cm as columns, the measurement was carried out using chloroform as the developing solvent.

[0052] Water absorption rate of fluorine-containing epoxy resin A film with a thickness of 0.1 mm was prepared, immersed in water under the condition of 23 °C, and the mass after 24 hours was designated as W24. After drying the film at 100 °C for 24 hours, the mass was designated as W0, and it was determined by the following formula. Water absorption rate = (W24 - W0) / W0 * 100 %

[0053] Moisture absorption rate of fluorine-containing epoxy resin A film with a thickness of 0.1 mm was prepared, kept in a thermo-hygrostat (SH-221 manufactured by Espec Corporation) at 85 °C and 85% for 24 hours, and the mass after that was designated as Z24. After drying the film after the test at 100 °C for 24 hours, the mass was designated as Z0, and it was determined by the following formula. Moisture absorption rate = (Z24 - Z0) / Z0 * 100 %

[0054] Glass transition temperature of fluorine-containing epoxy resin Using DSC (Differential Scanning Calorimeter: manufactured by SEIKO, RTG220), the temperature range from 30 °C to 250 °C was heated (first run) - cooled - heated (second run) at a rate of 10 °C / min, and the midpoint of the endothermic curve in the second run was taken as Tg (°C).

[0055] Dielectric constant and dielectric loss tangent of fluorine-containing epoxy resin Measured at 11 GHz using a cavity resonator (manufactured by Kanto Electronic Application Development Co., Ltd.) and analyzed using a network analyzer (manufactured by Agilent Technologies, Inc., model 8719ET).

[0056] Coefficient of thermal linear expansion of fluorine-containing epoxy resin Using a thermomechanical analyzer SS-6100 (manufactured by Seiko Instruments Inc.), the elongation of the film was measured under the conditions of tensile mode, temperature range of 25 to 150 °C, heating rate of 2 °C / min, initial load of 10 mN, and 10 mm between chucks. The average coefficient of thermal linear expansion was calculated using the following formula from the obtained measurement results. Here, L(30) is the sample length at 30 °C, and L(100) is the sample length at 100 °C. Average coefficient of thermal linear expansion = (1 / L(30))[(L(100) - L(30)) / (100 - 30)]

[0057] Example 1 86 g (0.21 mol) of the compound of the following formula A and 382 g (4.13 mol) of epichlorohydrin were mixed, 16.8 g (0.42 mol) of sodium hydroxide and 2 mL of water were added, and the mixture was heated to reflux with stirring. After reacting for 10 hours, the sodium chloride formed was removed by filtration through a glass filter, and the excess epichlorohydrin was removed under reduced pressure. When the purified product was examined by GPC, a fluorine-containing epoxy resin B1 with an epoxy equivalent of 290 was obtained, in which the ratio of the compounds with m = 0, 1, 2 in the following formula B was 93:6:1 (area ratio) and the average value of n was 0.08.

[0058]

Chemical formula

[0059]

Chemical formula

[0060] Example 2 The fluorine-containing epoxy compound with n = 0.08 obtained in Example 1 was subjected to vacuum distillation (138 °C to 150 °C / 1 mmHg), and a fluorine-containing epoxy resin B2 with an epoxy equivalent of 271 was obtained as an initial fraction, in which the ratio of the compounds with m = 0, 1, 2 in the formula B was 99:1:0 (area ratio) and the average value of n was 0.01.

[0061] Comparative Example 1 430 g (1 mol) of the compound of formula A and 750 g of a 10% aqueous sodium hydroxide solution (1.88 mol as NaOH) were heated and dissolved with stirring. While maintaining the solution at 58 °C, 145 g (1.57 mol) of epichlorohydrin was rapidly mixed, and the reaction was carried out at 58 - 63 °C for about 40 minutes and then refluxed for 10 hours. Purification was carried out in the same manner as in Example 1. When the purified product was examined by GPC, a fluorine-containing epoxy resin B3 in which the ratios of the compounds with m = 0, 1, 2, 3 in formula B were 29:32:23:16 (area ratio) and the average value of n was 1.27 was obtained. The epoxy equivalent was 609.

[0062] Comparative Example 2 430 g (1 mol) of the compound of formula A and 750 g of a 10% aqueous sodium hydroxide solution (1.88 mol as NaOH) were heated and dissolved with stirring. While maintaining the solution at 58 °C, 203 g (2.2 mol) of epichlorohydrin was gradually added, and the reaction was carried out at 58 - 63 °C for about 1 hour and then refluxed for 10 hours. Purification was carried out in the same manner as in Example 1. When the purified product was examined by GPC, a fluorine-containing epoxy resin B4 in which the ratios of the compounds with m = 0, 1, 2 in formula B were 80:15:5 (area ratio) and the average value of n was 0.25 was obtained. The epoxy equivalent was 331.

[0063] Example 3 384 g (4.8 mol) of an aqueous sodium hydroxide solution (50 wt%) was added to 328 g (0.8 mol) of bis(1,1,1,3,3,3-hexafluoro-2-hydroxyisopropyl)cyclohexane. The inside of the reaction system was purged with nitrogen, heated to 40 °C, 3.2 g (0.01 mol) of tetrabutylammonium bromide was added, and then 154 g (2 mol) of allyl chloride was gradually added dropwise and reacted. After completion of the reaction, 70 g of toluene was added, and the mixture was subjected to liquid separation. The organic layer was washed with water until it became neutral. After liquid separation, the organic layer was evaporated to remove the solvent and other components by an evaporator, and then a fluorine-containing allyl ether compound (structural formula C) was obtained by precision distillation.

[0064]

Chemical formula

[0065] Subsequently, the synthesis of the fluorine-containing epoxy resin by oxidation with hydrogen peroxide was carried out. 97 g (0.2 mol) of the fluorine-containing allyl ether compound of Structural Formula C, 300 g of benzonitrile, and 10 g (0.1 mol) of triethylamine were added. The reaction solution was adjusted to 80 °C, and 42 g (0.6 mol) of a 35% aqueous hydrogen peroxide solution was gradually added dropwise while stirring. After the addition was completed, the reaction solution was cooled to room temperature and stirred for 1 day. The reaction product was distilled to obtain about 12 g of the glycidyl ether compound of Formula D. The average value of n was 0, and this was designated as the fluorine-containing epoxy resin D1. The epoxy equivalent was 270.

[0066]

Chemical Formula

[0067] Example 4 To 100 parts of the epoxy resin obtained in Example 1, 2 parts of 2-ethyl-4-methylimidazole as a catalyst was added as a catalyst, and the mixture was heated to 50 °C and uniformly mixed to obtain a curable composition. The curable composition cured under the condition of 200 °C for 5 hours was used as a test piece, and the dielectric constant, dielectric loss tangent, and linear expansion coefficient were measured. The results are shown in Table 1.

[0068] Examples 5 and 6 A curable composition was prepared in the same manner as in Example 4, except that the fluorine-containing epoxy resins obtained in Example 2 (B2) and Example 3 (D1) were used in Example 4, and various physical properties of the cured product were measured. The results are shown in Table 1.

[0069] Comparative Examples 3 and 4 A curable composition was prepared in the same manner as in Example 4, except that the fluorine-containing epoxy resins obtained in Comparative Example 1 (B3) and Comparative Example 2 (B4) were used in Example 4, and various physical properties of the cured product were measured. The results are shown in Table 1.

[0070]

Table 1

[0071] Example 7 2 g of the fluorine-containing epoxy resin B1 obtained in Example 1, 8 g of a commercially available phenol cresol novolac epoxy resin (EPICLON N-673-80M manufactured by DIC Corporation, epoxy equivalent 208 g / eq), an equivalent amount of a commercially available phenol novolac resin (PHENOLITE TD-2093-60M manufactured by DIC Corporation, hydroxyl group equivalent 104 g / eq) as a curing agent, and 0.2 g of ethyl 4-methylimidazole as a curing accelerator were dissolved in methyl ethyl ketone to obtain a curable composition with a solid content concentration of 50%. This varnish was applied to Fukuda Metal CF-T9 electrolytic copper foil (12 μm thick), dried at 40° C. for 10 minutes, then dried at 120° C. for 10 minutes, and the coating-drying process was repeated once more to obtain a 50 μm thick resin-coated copper foil. Four sheets of this resin-coated copper foil were press-molded at 170° C. and 3 MPa to obtain a laminate. This was useful as a low-dielectric build-up material.

Claims

1. The following formula (E): 【Chemical 1】 (In the formula, n is an integer of 0 or more, and the average value of n is 0.18 or less. M is the following formula (E1): [Chemical 2] A group represented by, the following formula (E2): 【Chemical Formula 3】 A group represented by, or the following formula (E3): [Chemical Formula 4] (In the formula, Z is hydrogen or a fluoroalkyl group having 2 to 10 carbon atoms.) A printed circuit board for high frequencies containing a fluorine-containing epoxy resin, characterized by being represented by.)

2. The printed circuit board for high frequencies according to Claim 1, wherein the average value of n is 0.09 to 0.

18.

3. The printed circuit board for high frequencies according to Claim 1 or 2, wherein M is a group represented by the following formula (E2): [Chemical Formula 5]

4. The printed circuit board for high frequencies according to Claim 3, wherein the molar ratio (1,3-isomer / 1,4-isomer) of the 1,3-isomer and the 1,4-isomer of the group represented by the formula (E2) is 0 / 100 to 100 / 0.

5. The following formula (F): 【Chemical Formula 6】 (In the formula, M and n are the same as above) The printed circuit board for high frequencies according to Claim 1, wherein the content of the compound represented by is 0 to 10% by mass.

6. The following formula (G): HO - M - OH The printed circuit board for high frequencies according to Claim 1, wherein the content of the fluorine-containing diol represented by (in the formula, M is the same as defined above) is 0 to 10% by mass.

7. The following formula (G): HO - M - OH (In the formula, M is the following formula (E1): 【Chemical Formula 7】 A group represented by, the following formula (E2): 【Chemical 8】 A group represented by, or the following formula (E3): 【Chemical Formula 9】 (In the formula, Z is hydrogen or a fluoroalkyl group having 2 to 10 carbon atoms.) A fluorine-containing diol represented by, and a compound having a double bond are reacted to obtain a fluorine-containing olefin having two double bonds, and A method for producing a fluorine-containing epoxy resin, comprising a step of oxidizing the fluorine-containing olefin to obtain a fluorine-containing epoxy resin. ​

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