JP5390491B2 - Epoxy resin, production method thereof, epoxy resin composition and cured product - Google Patents

Description

  The present invention relates to an epoxy resin that gives a cured product excellent in high thermal decomposition stability, high heat resistance, low thermal expansibility, flame retardancy, low hygroscopicity, its production method, an epoxy resin composition using this epoxy resin, and It relates to the cured product, and is suitably used for insulating materials in the electric and electronic fields such as semiconductor sealing, printed wiring boards, and heat dissipation boards.

  In recent years, in electronic devices, high-density mounting of semiconductor packages, high integration and high speed of LSIs, and the like have been demanded, and materials with higher dimensional stability are required. Furthermore, with the progress of single-sided packaging of packages, reduction of package warpage has become an important issue, and development of a base resin having lower thermal expansion is required. In response to the above trend, measures to dissipate heat generated from the elements have become very important issues. More recently, in-vehicle electronic components are exposed to a high temperature environment for a long time, so that in addition to the physical heat resistance typified by the conventional glass transition point, a chemical typified by thermal decomposition stability. There is a strong demand for improved heat resistance.

  However, no conventionally known epoxy resins satisfy these requirements. For example, the well-known bisphenol type epoxy resin is in a liquid state at room temperature and is widely used because it is excellent in workability and easy to mix with a curing agent, an additive, etc. There is a problem in terms of moisture resistance. Also, phenol novolac type epoxy resins are known as improved heat resistance, but there are problems with moisture resistance and impact resistance. Patent Document 1 proposes an epoxy compound of a phenol aralkyl resin for the purpose of improving moisture resistance and impact resistance, but it is not sufficient in terms of heat resistance and flame retardancy.

  In Patent Document 2, an epoxy resin having a biphenyl and naphthalene structure with an increased aromatic structure content is proposed as having excellent flame retardancy, but still has a high thermal decomposition stability and low thermal expansion. Is not enough. Further, Patent Document 3 proposes a naphthol aralkyl type epoxy resin having a structure in which naphthol is linked by a naphthylene group. However, since all aromatic structures are naphthalene rings, viscosity and softening point are increased. There was a problem that the handleability and moldability were lowered. Further, it is still not sufficient in terms of thermal decomposition stability and low thermal expansion.

  For example, Non-Patent Document 1 shows an epoxy resin having an etheretherketone group as a material having excellent thermal decomposition stability. However, since it has strong crystallinity, it has a high melting point of 185 ° C. Therefore, it is difficult to adjust the epoxy resin composition and there is a problem in moldability. For example, since it is difficult to use the epoxy resin alone, an example in which the epoxy resin is used in combination with other epoxy resins is shown, but the usage ratio of the epoxy resin is still 15 mol%. In addition, since the epoxy equivalent of both is substantially the same, the weight ratio is 15 wt%. In this case, the curing agent is limited to acid anhydrides. Non-Patent Document 2 also shows an example of synthesizing an epoxy resin having the same structure. The melting point of the obtained epoxy resin is 175 ° C., and it is used as a varnish after being dissolved in a solvent. Requires highly polar DMF, NMP, m-cresol, and the like, and is greatly restricted from the viewpoint of practicality. Moreover, as an epoxy resin composition, there was a restriction | limiting in selection also in the hardening | curing agent from a compatible viewpoint. Although the physical properties of an epoxy cured product obtained using a diamine compound as a curing agent are disclosed, amine-based curing agents are problematic for application to electronic materials from the viewpoint of pot life and electrical insulation. was there.

JP 63-238122 A JP 2000-273281 A JP 2004-57992 A

S.H.Hwang, et.al., Polym.Adv.Technol., 12,441 (2001) K.S.Lee, et.al., Bull. Korean Chem. Soc., 22,424 (2001)

  Accordingly, the object of the present invention is to provide a cured product that is excellent in moldability and solvent solubility, as well as high thermal decomposition stability, high heat resistance, low thermal expansion, flame retardancy, low moisture absorption, and high thermal conductivity. It is to provide an epoxy resin to be provided, a production method thereof, an epoxy resin composition using the epoxy resin, and a cured product thereof.

（但し、ｍは１から１５の数を示し、ｎは０から１５の数を示す）

（但し、ｍは１から１５の数を示す） That is, the present invention is an epoxy resin obtained by reacting an epoxy resin represented by the following general formula (1) or a phenolic resin represented by the following general formula (2) with epichlorohydrin. Moreover, it is an epoxy resin whose sum of m and n is a number of 1 to 15 in General formula (1).

(However, m represents a number from 1 to 15, and n represents a number from 0 to 15.)

(Where m is a number from 1 to 15)

（但し、Ｘはハロゲン原子を示す） Moreover, this invention is a manufacturing method of the epoxy resin characterized by making the phenolic resin represented by the said General formula (2) react with epichlorohydrin. Here, as the phenolic resin represented by the general formula (2), a method obtained by reacting resorcinol with a condensing agent represented by the general formula (3) is suitable.

(However, X represents a halogen atom)

  Furthermore, this invention is an epoxy resin composition which consists of an epoxy resin and a hardening | curing agent, Comprising: Said epoxy resin was mix | blended as an epoxy resin component, It is an epoxy resin composition characterized by the above-mentioned. An inorganic filler can be blended in the epoxy resin composition. Moreover, this invention is a hardened | cured material obtained by hardening this epoxy resin composition.

  The epoxy resin of the present invention has a large chemical bond energy and an aromatic ether ether ketone unit having a large intermolecular force in the main chain structure, thereby being excellent in thermal decomposition stability, heat resistance, and low thermal expansion. At the same time, the cured product is excellent in flame retardancy and low hygroscopicity due to high aromaticity. On the other hand, by introducing a bent structure derived from resorcinol, crystallinity is suppressed, and melt mixing with a curing agent and the like, and solvent solubility are excellent. Thereby, compatibility of the handleability at the time of adjusting the epoxy resin composition which was difficult with the conventional epoxy resin, and the outstanding cured | curing material property is achieved.

GPC chart of phenolic resin of Reference Example 1 Infrared absorption spectrum of the phenolic resin of Reference Example 1 GPC chart of phenolic resin of Reference Example 2 GPC chart of the epoxy resin of Example 1 Infrared absorption spectrum of the epoxy resin of Example 1 GPC chart of the epoxy resin of Example 2

  Hereinafter, the present invention will be described in detail.

  First, the epoxy resin of this invention is demonstrated. In the general formula (1), m represents a number from 1 to 15, and this number is an average value (number average). m is preferably in the range of 1 to 10, more preferably 1 to 5, and even more preferably 1 to 2. In the epoxy resin of the present invention, m may consist of only one integer, and in this case, m is an integer of 1 to 15, preferably an integer of 1 or 2.

  n represents a number from 0 to 15, and a preferable value of n varies depending on the application to be applied. This number is an average value (number average). For example, for the use of a semiconductor encapsulant that requires a high filling rate of the filler, a material having a low viscosity is desirable, and the value of n is 0 to 5, preferably 0 to 2, and more preferably n. 0 is contained at 30 wt% or more. In the epoxy resin of the present invention, n can be composed of only one integer. In this case, n is an integer of 0 to 15, but preferably an integer of 0 or 1.

  The sum of m and n varies depending on the application used. For example, for a semiconductor encapsulant that requires a high filling factor of filler, one having a low viscosity is desirable, and the sum of m and n is preferably in the range of 1-15. Advantageously, the sum of m and n is 1 to 5, preferably 1 to 2, more preferably 50 wt% or more of the sum of 1. An epoxy resin in which m is 1 and n is an integer of 0 gives a low viscosity.

  In the general formula (1), m is 0, which is an epoxy resin of resorcinol, and does not correspond to the epoxy resin represented by the general formula (1) in the present invention. As a resin (diluent). If m is 0 as one of the epoxy resins represented by the general formula (1) in the present invention, the number average value of m is 0.1 to 5, preferably 0.2 to It is preferable that m is 0 in the range of 2. In this case, it is preferable that m is 1 and 30 wt% or more is included. When m is 0, the epoxy resin of the present invention is an epoxy resin mixture in which it is present.

  The epoxy resin of the present invention is produced, for example, by reacting the phenolic resin represented by the general formula (2) with epichlorohydrin. In the general formula (2), m has the same meaning as described in the general formula (1). The epoxy resin produced by reacting the phenolic resin represented by the general formula (2) and epichlorohydrin contains the epoxy resin represented by the general formula (1) as a main component. The phenolic resin represented by the general formula (2) may be a mixture of isomers.

  In the case of producing the epoxy resin of the present invention by reacting the phenolic resin represented by the general formula (2) with epichlorohydrin, or in the method for producing the epoxy resin of the present invention, it is represented by the general formula (2). A phenolic resin and epichlorohydrin are reacted. For the reaction between the phenolic resin and epichlorohydrin, 0.80 to 1.20 times equivalent, preferably 0.85 to 1.05 times equivalent of sodium hydroxide, potassium hydroxide, etc. with respect to the hydroxyl group in the phenolic resin. Alkali metal hydroxides are used. If it is less than this, the amount of residual hydrolyzable chlorine increases, which is not preferable. The metal hydroxide is used in an aqueous solution or solid state.

  In the reaction, an excessive amount of epichlorohydrin is used with respect to the phenolic resin. Usually, 1.5 to 15 times mole of epichlorohydrin is used with respect to 1 mole of hydroxyl group in the phenolic resin, preferably in the range of 2 to 8 times mole. If it is more than this, the production efficiency will be reduced, and if it is less than this, the amount of epoxy resin high molecular weight will be increased and the viscosity will be high.

  The reaction is usually performed at a temperature of 120 ° C. or lower. If the temperature is high during the reaction, the amount of so-called hardly hydrolyzable chlorine increases and it becomes difficult to achieve high purity. Preferably it is 100 degrees C or less, More preferably, it is the temperature of 85 degrees C or less.

  In the reaction, a quaternary ammonium salt or a polar solvent such as dimethyl sulfoxide or diglyme may be used. Examples of the quaternary ammonium salt include tetramethylammonium chloride, tetrabutylammonium chloride, benzyltriethylammonium chloride, and the addition amount thereof ranges from 0.1 to 2.0 wt% with respect to the phenolic resin. preferable. If the amount is less than this, the effect of adding a quaternary ammonium salt is small. If the amount is more than this, the amount of hardly hydrolyzable chlorine produced increases, and high purity becomes difficult. Moreover, as addition amount of a polar solvent, the range of 10-200 wt% is preferable with respect to phenolic resin. If the amount is less than this, the effect of addition is small.

  After completion of the reaction, excess epichlorohydrin and solvent are distilled off, the residue is dissolved in a solvent such as toluene and methyl isobutyl ketone, filtered, washed with water to remove inorganic salts and residual solvent, and then the solvent is distilled off. It can be set as an epoxy resin.

  Advantageously, the obtained epoxy resin is further added with 1 to 30 times the amount of alkali metal hydroxide such as sodium hydroxide or potassium hydroxide with respect to the remaining hydrolyzable chlorine, and a re-ring closure reaction is carried out. Is called. The reaction temperature at this time is usually 100 ° C. or lower, preferably 90 ° C. or lower.

The phenolic resin represented by the general formula (2) can be obtained by a known method. Advantageously, there is a method of reacting resorcinol with a condensing agent represented by the general formula (3). X represents a group (atom) that undergoes a condensation reaction with OH, and is preferably a halogen atom. Here, it is preferable to react 0.1 to 0.9 mol of the condensing agent represented by the general formula (3) with respect to 1 mol of resorcinol.
If resorcinol is used in an amount twice as much as the condensing agent, a phenolic resin mainly composed of a phenolic resin in which m is 1 or more in general formula (2) can be obtained. If resorcinol is used in excess of 2 moles, a phenolic resin containing resorcinol in which m is 0 can be obtained. In order to ensure that both ends have a phenolic group, resorcinol should be used in an amount of more than 2 moles, preferably 3 to 10 moles. Resorcinol remaining in the system after the reaction may be used as it is in the epoxidation reaction or removed as a phenolic resin mixture containing resorcinol without being removed. As a removal method, a method such as vacuum distillation or water washing can be applied.

  When selectively obtaining a phenolic resin having m of 2 or more, the molar ratio of resorcinol to the condensing agent should be close to 1: 1, and a phenolic resin having a larger m can be obtained as the ratio is closer to 1: 1. . And when obtaining the phenolic resin whose m is an integer of 1-15, after obtaining the phenolic resin which consists of a mixture of the component from which m differs, it is advantageous to distill or chromatograph this. Note that the phenolic resin in which m is 0 is resorcinol, which gives an epoxy resin in which n is 0 in the general formula (1) as described above. It is good to leave.

  The epoxy resin composition of the present invention is an epoxy resin produced by reacting an epoxy resin represented by the above general formula (1) or a phenolic resin represented by the general formula (2) with epichlorohydrin (hereinafter, referred to as “epoxy resin”). These are collectively referred to as the epoxy resin of the present invention) and a curing agent as essential components. As a hardening | curing agent mix | blended with the epoxy resin composition of this invention, what is generally known as a hardening | curing agent of an epoxy resin can be used. Examples include dicyandiamide, polyhydric phenols, acid anhydrides, aromatic and aliphatic amines.

  Specifically, examples of polyhydric phenols include bisphenol A, bisphenol F (isomer mixture), 4,4′-dihydroxydiphenylmethane, 4,4′-dihydroxydiphenyl ether, and 4,4′-dihydroxybenzophenone. 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxydiphenyl sulfone, fluorene bisphenol, 4,4′-dihydroxybiphenyl, 2,2′-dihydroxybiphenyl, hydroquinone, resorcin, 1,5-naphthalenediol, 1 , 6-naphthalenediol, 2,6-naphthalenediol, 2,7-naphthalenediol, etc., or tris (hydroxyphenyl) methane mixture, tris- (4-hydroxyphenyl) methane, 1, , 2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolac, o- cresol novolak, naphthol novolak, a trivalent or more phenols represented by polyvinyl phenol. Furthermore, phenols such as phenol and o-cresol, monovalent phenols such as naphthols, bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4′-biphenol, 2,2′-biphenol, Divalent phenols such as hydroquinone, resorcin, naphthalenediol, formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, 1,4-dihydroxymethylbenzene, 1,4-dimethoxymethylbenzene, 1,4-bischloromethylbenzene 4,4′-dihydroxymethylbiphenyl, 4,4′-dimethoxymethylbiphenyl, 4,4′-bischloromethylbiphenyl, 1,5-bischloromethylnaphthalene, 1,4-bischloromethylnaphthalene There are polyhydric phenolic compounds synthesized by condensation agent. Moreover, you may use the phenolic resin represented by the said General formula (2) as a part or all of a hardening | curing agent.

  Examples of the acid anhydride include phthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyl hymic anhydride, nadic anhydride, and trimellitic anhydride.

  Examples of amines include 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenylsulfone, m-phenylenediamine, p-xylylenediamine, 1,5-diaminonaphthalene. Aromatic amines such as ethylenediamine, hexamethylenediamine, diethylenetriamine, and triethylenetetramine.

  Among the curing agents, it is preferable to use a phenolic compound from the viewpoints of electrical insulation, low hygroscopicity, high thermal conductivity, low thermal expansion, and the like. In particular, from the viewpoint of thermal decomposition stability, low thermal expansion, and low hygroscopicity of the cured product, an aralkyl type obtained by condensing phenols with 1,4-dihydroxymethylbenzene, 4,4′-dimethoxymethylbiphenyl, etc. It is desirable to use a phenolic resin or a phenolic resin represented by the general formula (2). From the viewpoint of heat resistance and high thermal conductivity, polyhydric phenolic compounds such as phenol novolac, tris (hydroxyphenyl) methanes, 1,1,2,2-tetrakis (hydroxyphenyl) ethanes are desirable.

  In the resin composition of the present invention, one or more of the above curing agents can be mixed and used.

  Moreover, you may mix | blend another kind of epoxy resin other than the epoxy resin of this invention as an epoxy resin component in the epoxy resin composition of this invention. As the epoxy resin in this case, all ordinary epoxy resins having two or more epoxy groups in the molecule can be used. Examples include resorcinol, bisphenol A, 4,4'-dihydroxydiphenylmethane, bisphenol A, bisphenol F (isomer mixture), 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl ether, 4,4'- Dihydroxybenzophenone, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfone, fluorene bisphenol, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, hydroquinone, resorcinol, 1,5-naphthalenediol , 1,6-naphthalenediol, 2,6-naphthalenediol, 2,7-naphthalenediol, etc., or phenol novolak, bisphenol A novolak, o- Resole novolak, m-cresol novolak, p-cresol novolak, xylenol novolak, poly-p-hydroxystyrene, tris (hydroxyphenyl) methane mixture, tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, fluoroglycinol, pyrogallol, t-butyl pyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, phenol aralkyl resin, Derived from aralkyl-type phenol resin having 4,4′-biphenylene group, trivalent or higher phenols such as dicyclopentadiene resin, or halogenated bisphenols such as tetrabromobisphenol A There is that glycidyl ether product and the like. These epoxy resins can be used alone or in combination of two or more. And in the case of the composition which uses the epoxy resin of this invention as an essential component, the compounding quantity of the epoxy resin of this invention is 30-100 wt% in the whole epoxy resin, Preferably it is good to be the range of 60-100 wt%. If it is less than this, the improvement effects such as high thermal decomposition stability, high heat resistance, low thermal expansion, flame retardancy, low hygroscopicity, and high thermal conductivity when cured are small.

  In addition, an appropriate amount of an inorganic filler can be added to the epoxy resin composition of the present invention. Examples of the inorganic filler include metals, metal oxides, metal nitrides, metal carbides, metal hydroxides, and carbon materials. As the metal, silver, copper, gold, platinum, zircon, etc., as the metal oxide, silica, alumina, magnesium oxide, titanium oxide, tungsten trioxide, etc., as the metal nitride, boron nitride, aluminum nitride, silicon nitride, etc. Metal carbide as silicon carbide, metal hydroxide as aluminum hydroxide, magnesium hydroxide, etc., carbon material as carbon fiber, graphitized carbon fiber, natural graphite, artificial graphite, spherical graphite particles, mesocarbon microbeads, Examples include whisker-like carbon, microcoil-like carbon, nanocoil-like carbon, carbon nanotube, and carbon nanohorn. As the shape of the inorganic filler, a crushed shape, a spherical shape, a whisker shape, and a fibrous shape can be applied, but a spherical shape is preferable in order to increase the filling rate. In order to ensure the insulating property and high thermal conductivity of the cured epoxy resin, a metal oxide is preferable as the inorganic filler, and alumina, boron nitride, and aluminum nitride are particularly preferable. These inorganic fillers may be blended singly or in combination of two or more. Ordinary coupling agent treatment may be applied to the inorganic filler for the purpose of improving the wettability between the inorganic filler and the epoxy resin, reinforcing the interface of the inorganic filler, and improving the dispersibility.

  The blending amount of the inorganic filler is preferably 50 wt% or more, more preferably 70 wt% or more. If it is less than this, the effect of improving thermal conductivity is small. The amount of the inorganic filler used is usually 75 wt% or more from the viewpoint of low hygroscopicity and high solder heat resistance, and particularly preferably 80 wt% or more.

  A conventionally well-known hardening accelerator can be used for the epoxy resin composition of this invention. Examples include amines, imidazoles, organic phosphines, Lewis acids, etc., specifically 1,8-diazabicyclo (5,4,0) undecene-7, triethylenediamine, benzyldimethylamine, Tertiary amines such as ethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol, imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, Organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine, tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / ethyltriphenyl Rate, tetra-substituted phosphonium tetra-substituted borate such as tetrabutylphosphonium-tetrabutyl borate, 2-ethyl-4-methylimidazole · tetraphenyl borate, and the like tetraphenyl boron salts such as N- methylmorpholine tetraphenylborate. As addition amount, it is the range of 0.2-10 weight part normally with respect to 100 weight part of epoxy resins.

  Further, the epoxy resin composition of the present invention includes polyester, polyamide, polyimide, polyphenylene ether, polyetherimide, polyphenylene sulfide, polyether sulfone, liquid crystal polymer, polyether, polyurethane, petroleum resin, indene coumarone resin, phenoxy. An oligomer or a polymer compound such as a resin may be blended as appropriate, and additives such as pigments, refractory agents, thixotropic agents, coupling agents, fluidity improvers, and the like may be blended. Examples of the pigment include organic or inorganic extender pigments and scaly pigments. Examples of the thixotropic agent include silicon-based, castor oil-based, aliphatic amide wax, polyethylene oxide wax, and organic bentonite. Further, if necessary, the resin composition of the present invention includes halogen-based flame retardants such as brominated epoxies, phosphorus-based flame retardants such as red phosphorus, phosphate esters, and phosphorus atom-containing epoxy resins, and antimony trioxide. Flame retardant aids, mold release agents such as carnauba wax and ester wax, coupling agents such as γ-glycidoxypropyltrimethoxysilane, colorants such as carbon black, low stress agents such as silicone oil, calcium stearate Additives such as a lubricant such as epoxy silane, amino silane, ureido silane, vinyl silane, alkyl silane, organic titanate, and aluminum alcoholate can be used.

  The epoxy resin composition of the present invention is generally kneaded with a mixing roll, an extruder, etc., after thoroughly mixing the above-mentioned epoxy resin, curing agent component and other compounding components at a predetermined compounding amount with a mixer or the like, It can be obtained by cooling and grinding.

  Alternatively, the above blended components may be aromatic solvents such as benzene, toluene, xylene, chlorobenzene, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, aliphatic hydrocarbon solvents such as hexane, heptane, methylcyclohexane, ethanol, Alcohol solvents such as isopropanol, butanol and ethylene glycol, ether solvents such as diethyl ether, dioxane, tetrahydrofuran and diethylene glycol dimethyl ether, polarities such as N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide and N-methylpyrrolidone It can be dissolved in a solvent to obtain a varnish-like epoxy resin composition. The varnish-like epoxy resin composition can be made into a prepreg-like epoxy composition by impregnating a fibrous filler such as glass fiber, carbon fiber, or aramid fiber and then removing the organic solvent by drying.

  In order to obtain a cured product using the epoxy resin composition of the present invention, for example, methods such as transfer molding, press molding, cast molding, injection molding, and extrusion molding are applied. Moreover, methods, such as a vacuum press, are taken as a method for hardening the prepreg-like epoxy resin composition. The temperature at this time is usually in the range of 120 to 220 ° C.

  The cured epoxy resin of the present invention can be obtained by heating and curing with the above molding method. Usually, the molding temperature is 80 ° C. to 250 ° C., and the molding time is 1 minute to 20 hours. In order to increase the crystallinity of the cured epoxy resin, it is desirable to cure at a low temperature for a long time. The preferred curing temperature is in the range of 100 ° C to 180 ° C, more preferably 120 ° C to 160 ° C. The preferable curing time is 10 minutes to 6 hours, more preferably 30 minutes to 3 hours. Further, the crystallinity can be further increased by post-cure after molding. Usually, the post-cure temperature is 130 ° C. to 250 ° C., and the time is in the range of 1 hour to 20 hours, but preferably 1 hour at a temperature 5 ° C. to 40 ° C. lower than the endothermic peak temperature in differential thermal analysis. It is desirable to perform post-cure over 24 hours from the beginning.

  The cured epoxy resin of the present invention can be laminated with another type of substrate. As the base material to be laminated, it is in the form of a sheet, a film, a metal base material such as copper foil, aluminum foil, stainless steel foil, polyethylene, polypropylene, polystyrene, polyacrylate, polymethacrylate, polyethylene terephthalate, polybutylene terephthalate, Examples thereof include polymer base materials such as polyethylene naphthalate, liquid crystal polymer, polyamide, polyimide, and polytetrafluoroethylene.

  Hereinafter, the present invention will be described more specifically with reference to examples. In the examples, the molecular weight, physical properties, and the like were measured by sample preparation and measurement according to the following methods.

1) Molecular weight distribution of phenolic resin and epoxy resin Using a GPC measuring device (manufactured by Nippon Waters, 515A type GPC), three TSKgel G2000HXL (manufactured by Tosoh) and one TSKgel G4000HXL (manufactured by Tosoh) are used for detection. The measurement was carried out with RI as the solvent, tetrahydrofuran as the solvent, a flow rate of 1.0 ml / min, and a column temperature of 38 ° C.

2) Melt viscosity Measured at 150 ° C. using a CAP2000H rotational viscometer manufactured by BROOKFIELD.

3) Measurement of hydroxyl group equivalent Using a potentiometric titrator, 1,4-dioxane is used as a solvent, acetylation is performed with 1.5 mol / L acetyl chloride, and excess acetyl chloride is decomposed with water to 0.5 mol / L. -Titration using potassium hydroxide.

4) Measurement of epoxy equivalent Using a potentiometric titrator, methyl ethyl ketone was used as a solvent, a brominated tetraethylammonium acetic acid solution was added, and the potential was measured using a 0.1 mol / L perchloric acid-acetic acid solution.

5) Hydrolyzable chlorine 0.5 g of the sample was dissolved in 30 ml of dioxane, 1N-KOH, 10 ml was added and the mixture was boiled and refluxed for 30 minutes, cooled to room temperature, and further added with 100 ml of 80% acetone water. It was measured by potentiometric titration with 002N-AgNO ₃ aqueous solution.

6) Infrared absorption spectrum It measured by the KBr tablet method with the JEOL make and JIR-100 type | mold measuring apparatus.

7) State of composition The prepared epoxy resin composition (before curing) was visually observed to evaluate the uniformity of mixing. ○: Good uniformity, Δ: Slightly undissolved portion remains, ×: Many undissolved portions of the epoxy resin remain and poor uniformity.

8) Thermogravimetric measurement Using a TG / DTA6200 model manufactured by Seiko Denshi Kogyo Co., Ltd. and a differential thermothermal gravimetric analyzer, the temperature was increased at a rate of 10 ° C / min in a nitrogen stream. The temperature at 5 wt% weight reduction (T-5%), the temperature at 10 wt% weight reduction (T-10%), and the residual carbon ratio at 700 ° C. were determined.

9) Linear expansion coefficient, glass transition point (Tg)
Using a TMA120C thermomechanical measuring device manufactured by Seiko Instruments Inc., the temperature was increased at a rate of 10 ° C./min.

10) Water absorption rate The rate of change in weight after absorbing water for 100 hours under conditions of 85 ° C and 85% relative humidity.

11) Bending strength It measured according to JIS-K-6911.

Reference example 1
In a 2 L separable flask, 87.3 g (0.4 mol) of 4,4′-difluorobenzophenone, 176.2 g (1.6 mol) of resorcinol, 221 g of anhydrous potassium carbonate, 940 g of N-methylpyrrolidone (NMP) Then, 140 g of toluene was charged and stirred at room temperature for 1 hour under a nitrogen stream. Then, it heated up at 140 degreeC and stirred for 4 hours, distilling off water. Thereafter, the mixture was further heated to 205 ° C. and stirred for 4 hours while distilling off NMP. After cooling, the reaction product was added dropwise to a large amount of water (5 L), and the product was filtered through a glass filter. The product was dissolved in 900 g of MIBK, neutralized with 30% aqueous sulfuric acid solution, and washed with water repeatedly. Thereafter, MIBK was removed from the MIBK layer under reduced pressure to obtain 117 g of a resinous solid (phenol resin A). The softening point is 102.5 ° C., the melt viscosity at 150 ° C. is 1.49 Pa · s, and the OH equivalent is 172 g / eq. Met. A GPC chart is shown in FIG. From the GPC measurement, the product component ratio is 54.8% for m = 1 in the general formula (2), 23.4% for m = 2, 19.1% for m ≧ 3, and 2.7% for others. there were. The infrared absorption spectrum is shown in FIG.

Reference example 2
In a 2 L separable flask, 65.5 g (0.6 mol) of 4,4′-difluorobenzophenone, 66.1 g (0.6 mol) of resorcinol, 165.7 g of anhydrous potassium carbonate, N-methylpyrrolidone (NMP) 770 g and 120 g of toluene were charged and stirred at room temperature for 1 hour under a nitrogen stream. Then, it heated up at 140 degreeC and stirred for 4 hours, distilling off water. Thereafter, the temperature was further raised to 160 ° C., and the mixture was stirred under reduced pressure for 4 hours while distilling off NMP. After returning to room temperature, 900 g of MIBK was added and dissolved, neutralized with a 30% aqueous sulfuric acid solution, and then washed with water repeatedly. Thereafter, MIBK was removed from the MIBK layer under reduced pressure, and further heated and stirred at 210 ° C. for 4 hours to remove the remaining resorcinol to obtain 67 g of a resinous solid (phenol resin B). The softening point is 132 ° C., the melt viscosity at 180 ° C. is 3.2 Pa · s, and the OH equivalent is 468 g / eq. Met. A GPC chart is shown in FIG. From the GPC measurement, the product component ratio is 10.5% for m = 1, 14.5% for m = 2, 14.2% for m = 3, and 12.2 for m = 4 in the general formula (2). 6%, m = 5 was 9.9%, m = 6 was 7.4%, m ≧ 7 was 26.9%, and the others were 4.0%.

Example 1
30.0 g of phenol resin A obtained in Reference Example 1, 112.9 g of epichlorohydrin, and 16.9 g of diethylene glycol dimethyl ether were charged, and 14.6 g of 48.8% aqueous sodium hydroxide solution was added at 65 ° C. under reduced pressure (about 130 Torr). The solution was added dropwise over 3 hours. During this time, the generated water was removed from the system by azeotropy with epichlorohydrin, and the distilled epichlorohydrin was returned to the system. After completion of the dropwise addition, the reaction was continued for another hour and dehydrated. Thereafter, epichlorohydrin was removed under reduced pressure, and 93 g of MIBK was added and dissolved therein, the produced salt was removed by filtration, and further washed with water, and then the MIBK solution was recovered. To this, 5.3 g of 48.8% potassium hydroxide aqueous solution was added and reacted at 80 ° C. for 2 hours. Then, after repeating washing with water, MIBK was removed from the MIBK layer under reduced pressure to obtain 30.5 g of a resinous solid (epoxy resin A). The softening point is 62 ° C., the melt viscosity at 150 ° C. is 0.2 Pa · s, hydrolyzable chlorine is 380 ppm, and the epoxy equivalent is 252 g / eq. Met. A GPC chart is shown in FIG. 4, and an infrared absorption spectrum is shown in FIG. Shown in The obtained epoxy resin was easily soluble in MIBK and toluene, and a resin solution of 50 wt% or more could be adjusted.

Example 2
30.0 g of phenol resin B obtained in Reference Example 2, 59.3 g of epichlorohydrin, and 8.9 g of diethylene glycol dimethyl ether were charged, and 5.3 g of 48.8% sodium hydroxide aqueous solution was added at 65 ° C. under reduced pressure (about 130 Torr). The solution was added dropwise over 3 hours. During this time, the generated water was removed from the system by azeotropy with epichlorohydrin, and the distilled epichlorohydrin was returned to the system. After completion of the dropwise addition, the reaction was continued for another hour and dehydrated. Thereafter, epichlorohydrin was removed under reduced pressure, and 80 g of MIBK was added and dissolved therein, and the produced salt was removed by filtration, and after further washing with water, the MIBK solution was recovered. To this, 1.8 g of 48.8% potassium hydroxide aqueous solution was added and reacted at 80 ° C. for 2 hours. Then, after repeating washing with water, MIBK was removed from the MIBK layer under reduced pressure to obtain 34.7 g of a resinous solid (epoxy resin B). The softening point is 94 ° C., the melt viscosity at 150 ° C. is 3.6 Pa · s, the hydrolyzable chlorine is 320 ppm, and the epoxy equivalent is 422 g / eq. Met. A GPC chart is shown in FIG. The obtained epoxy resin was easily soluble in MIBK and toluene, and a resin solution of 50 wt% or more could be adjusted.

Reference example 3
In a 2 L separable flask, 87.3 g (0.4 mol) of 4,4′-difluorobenzophenone, 176.2 g (1.6 mol) of hydroquinone, 98.7 g of 86.0% potassium carbonate, N-methylpyrrolidone (NMP) ) 941 g and 145 g of toluene were charged and stirred at room temperature for 1 hour under a nitrogen stream. Then, it heated up at 140 degreeC and stirred for 4 hours, distilling off water. Thereafter, the mixture was further heated to 205 ° C. and stirred for 4 hours while distilling off NMP. After cooling, the reaction product was added dropwise to a large amount of water (5 L), and the product was filtered through a glass filter. The product was further recovered by washing with 1500 ml of water. Then, after neutralizing with 30% sulfuric acid aqueous solution, it was dried to obtain 150.8 g of a solid. The melting point peak based on the capillary method was 208.3 ° C. to 215.4 ° C. The OH equivalent was 214.0 g / eq.

Comparative Example 1
40.0 g of the phenolic compound obtained in Reference Example 3, 864.5 g of epichlorohydrin, and 120 g of diethylene glycol dimethyl ether were charged, and 18.0 g of 48.8% aqueous sodium hydroxide solution was added over 3 hours at 65 ° C. under reduced pressure (about 130 Torr). And dripped. During this time, the generated water was removed from the system by azeotropy with epichlorohydrin, and the distilled epichlorohydrin was returned to the system. After completion of the dropwise addition, the reaction was continued for another hour and dehydrated. Thereafter, epichlorohydrin was concentrated, and this was added dropwise to 2 L of MeOH. The resulting product was filtered, washed with ethanol, and dried to obtain 29.5 g of a white powdery epoxy resin (epoxy resin C). From GPC measurement, n = 1 was 97.9%, and n = 2 bodies was 2.1%. Hydrolyzable chlorine is 450 ppm, epoxy equivalent is 262 g / eq. The melting point obtained by the capillary method at a heating rate of 2 ° C./min was 192.7 ° C. to 194.6 ° C. The obtained epoxy resin was hardly soluble in MIBK and toluene, and a resin solution of 10 wt% or more could not be prepared.

Examples 3-8 and Comparative Examples 2-4
As epoxy resin components, the epoxy resins synthesized in Examples 1 and 2 (epoxy resins A and B), the epoxy resin synthesized in Comparative Example 1 (epoxy resin C), and the biphenyl type epoxy resin (epoxy resin D; manufactured by Mitsubishi Chemical Corporation) YX-4000H, epoxy equivalent 195, melting point 105 ° C.), as a curing agent component, phenol resins (phenol resins A and B) synthesized in Reference Examples 1 and 2, phenol aralkyl resins (phenol resin C; manufactured by Meiwa Kasei Co., Ltd.) MEH-7800SS, OH equivalent 175, softening point 67 ° C.) and phenol novolak (phenol resin D; manufactured by Gunei Chemical Co., PSM-4261; OH equivalent 103, softening point 82 ° C.) were used. These resin components are made into fine powders of 1 mm pass with a pulverizer, further mixed with the composition shown in Table 1 using triphenylphosphine as a curing accelerator, kneaded with a heating roll at 100 ° C. and epoxy. A resin composition was obtained. The epoxy resin composition was molded at 150 ° C., post-cured at 175 ° C. for 6 hours to obtain a cured product test piece, and then subjected to various physical property measurements. Table 1 shows the evaluation results. The uniformity of the adjusted epoxy resin composition was visually observed. In addition, the compounding quantity shown in Table 1 is a weight part.

Claims (5)

An epoxy resin represented by the following general formula (1).

(However, m represents a number from 1 to 15, and n represents a number from 0 to 15.)   The epoxy resin according to claim 1, wherein the sum of m and n is 1 to 15 in the general formula (1). The epoxy resin according to claim 1, obtained by reacting a phenolic resin represented by the following general formula (2) with epichlorohydrin.

(Where m is a number from 1 to 15) A method for producing an epoxy resin, comprising reacting a phenolic resin represented by the following general formula (2) with epichlorohydrin.

(Where m is a number from 1 to 15) The phenolic resin represented by the general formula (2) is obtained by reacting 0.1 to 0.9 moles of the condensing agent represented by the general formula (3) with respect to 1 mol of resorcinol, and then the phenol. The method for producing an epoxy resin according to claim 4, wherein a reactive resin and epichlorohydrin are reacted.

(However, X represents a halogen atom)

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