JP4665410B2 - Epoxy resin composition - Google Patents

Description

The present invention is flowable, a solvent solubility is satisfactory, relates to an epoxy resin composition capable of giving a cured product having excellent heat resistance and the like.

  Epoxy resins can be cured with various curing agents, resulting in cured products that are generally excellent in low shrinkage (dimensional stability), electrical insulation, and chemical resistance during curing. Due to technological innovation in the field of high-performance paints, even better heat resistance is required. As this heat resistance improving means, for example, there is a method of using a high-nuclear number type (high molecular weight type) phenol novolac resin as a curing agent, but its own viscosity is high, and the resulting epoxy resin composition flows. It becomes difficult to apply to fine structure parts such as advanced semiconductors and substrates. In addition, the use of a crystalline polyfunctional phenol compound having high symmetry as a curing agent has been studied, but in the case of a tetrafunctional or higher compound that can be expected to have excellent heat resistance, the melting point is almost 150 ° C. or more without exception. Yes, the compatibility with the epoxy resin and the solvent solubility are extremely poor, and it is not suitable as a curing agent.

  In addition, a technique has been proposed in which a hydroxyl group of a phenol compound containing a phosphorus atom is acetalized and used as a curing agent for a polyfunctional epoxy resin to obtain a cured product having high flame retardancy (for example, Patent Document 1). However, since the phenol compound used in the examples is bifunctional, it is difficult to obtain a cured product having excellent heat resistance, and further improvement is required.

JP 2003-286293 A (pages 3 to 6)

In view of the actual situation as described above, an object of the present invention is to develop an epoxy resin composition that can solve the above problems by developing a curing agent that is excellent in fluidity, solvent solubility, and heat resistance of a cured product to be obtained. It is to provide.

The present inventor has intensively studied to solve the above problems, contain more than two aromatic hydroxyl groups in the molecule and having a melting point 0.99 ° C. or more crystalline compounds der Ru polyhydroxy compound (a) The present inventors have found that the above-mentioned problems can be solved by using a polyacetal compound (A) in which 10 to 100 mol% of the aromatic hydroxyl group therein is acetalized as a curing agent, and the present invention has been completed.

That is, the present invention contains 10 to 100 mol% of the aromatic hydroxyl group in the polyhydroxy compound (a) which is a crystalline compound containing more than two aromatic hydroxyl groups in one molecule and having a melting point of 150 ° C. or higher. It contains an acetalized polyacetal compound (A) and an epoxy resin (B) to provide an epoxy resin composition.

  The polyacetal compound used in the present invention has low viscosity, high fluidity, excellent compatibility with epoxy resins and solvent solubility, and the resulting cured product is required in the recent electronics field and high-performance paint field. Satisfy high heat resistance. In addition, this technology is expected as an ultra-high heat-resistant curing agent with a rigid skeleton and high symmetry, but it has been applied as a curing agent for conventional epoxy resins due to its too high melting point, compatibility and solvent solubility. It is possible to improve the compatibility of the curing agent by modifying the crystallizable polyhydric phenol compound, which has been impossible, without significant performance deterioration.

Hereinafter, the present invention will be described in detail.
The epoxy resin composition of the present invention contain more than two aromatic hydroxyl groups per molecule and having a melting point 0.99 ° C. or more crystalline compounds der Ru polyhydroxy compound (a) in an aromatic hydroxyl group It is an epoxy resin composition comprising a polyacetal compound (A) and an epoxy resin (B) in which 10 to 100 mol% are acetalized as essential components.

The polyacetal compound (A) contains more than two aromatic hydroxyl groups per molecule and having a melting point 0.99 ° C. or more crystalline compounds der Ru polyhydroxy compound (a) 10 of aromatic hydroxyl groups in It is obtained by reacting ˜100 mol% with a compound capable of forming an acetal group, and from the viewpoint of industrial availability, a method of acetalization reaction using vinyl ethers is preferred. The number of aromatic hydroxyl groups in the polyhydroxy compound (a) is not preferably 2 or less from the viewpoint of the heat resistance of the resulting cured product. Furthermore, when the polyhydroxy compound (a) having more than 3 aromatic hydroxyl groups in one molecule is used, the heat resistance of the cured product can be further improved, and the effects of the present invention can be further realized. To preferred.

  The acetalization reaction using vinyl ethers is represented by the following chemical reaction formula (1)

で表される反応である。この反応により、ポリヒドロキシ化合物（ａ）中の芳香族性水酸基がビニルエーテル類によりブロックされ、該ポリヒドロキシ化合物（ａ）の粘度、溶剤溶解性等を改善することが出来る。更にこのアセタール化反応は可逆反応であることから、得られるポリアセタール化合物（Ａ）と後述するエポキシ樹脂（Ｂ）とを混合した場合には、脱ブロックによってアセタール基が水酸基に戻り、エポキシ基との硬化反応を行わせることが可能となるものである。

It is a reaction represented by By this reaction, the aromatic hydroxyl group in the polyhydroxy compound (a) is blocked with vinyl ethers, and the viscosity and solvent solubility of the polyhydroxy compound (a) can be improved. Furthermore, since this acetalization reaction is a reversible reaction, when the polyacetal compound (A) obtained and the epoxy resin (B) described below are mixed, the acetal group returns to a hydroxyl group by deblocking, and It is possible to cause a curing reaction.

  The higher the acetalization rate, the greater the effect of reducing the viscosity. Therefore, when the acetalization rate of the aromatic hydroxyl group in the polyhydroxy compound (a) is less than 10 mol%, the effect of reducing the viscosity is small, which is not preferable. Moreover, since there exists a tendency for hardening reactivity with an epoxy resin (B) to fall when an acetalization rate is high, it is preferable to adjust an acetalization rate suitably considering a desired characteristic.

Polyhydroxy compounds containing more than two aromatic hydroxyl groups in the molecule (a), since it enhances the heat resistance of the resulting cured product, melting point Ru Ah at above 0.99 ° C. Crystalline Compound . Furthermore, in particular a tetravalent hydroxy compound in the crystal compound is preferred. Specifically, 2, 7-dimers dihydroxynaphthalene is bonded via a methylene group at the 1-position to each other, 1,1 ', provides such superior heat resistance 2,2'-tetrahydroxy-trishydroxyphenylmethane As a base compound.

  The vinyl ethers are not particularly limited as long as they are compounds containing one or more vinyl ether groups in one molecule, but monovinyl ethers are mainly used from the viewpoint of improving the fluidity of the resulting polyacetal compound (A). It is preferable to use as a component, for example, an aliphatic monovinyl ether, an alicyclic monovinyl ether, a cyclic vinyl ether compound, etc. are mentioned. Specific examples of the aliphatic monovinyl ether include methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, n-propyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, 2-ethylhexyl vinyl ether and the like. Examples of the alicyclic vinyl ether include cyclohexyl monovinyl ether. Examples of cyclic vinyl ether compounds include 2,3-dihydrofuran, 3,4-dihydrofuran, 2,3-dihydro-2H-pyran, 3,4-dihydro-2H-pyran, and 3,4-dihydro-2-methoxy. -2H-pyran, 3,4-dihydro-4,4-dimethyl-2H-pyran-2-one, 3,4-dihydro-2-ethoxy-2H-pyran, 3,4-dihydro-2H-pyran-2 -Sodium carboxylate etc. are mentioned, It can use individually or as a mixture of 2 or more types. Among these, n-propyl vinyl ether and n-butyl vinyl ether are easy to obtain industrially, have a low deblocking dissociation temperature upon reaction with the epoxy resin (B) described later, and have good reactivity. 2-ethylhexyl vinyl ether is preferred. Moreover, you may use vinyl ethers other than the said monovinyl ether for the purpose of the modification effect of the polyacetal compound (A) obtained, As a use ratio at this time, 20 mol% or less with respect to the said monovinyl ether Is preferably used. Examples of the other vinyl ethers include, for example, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,4-butanedidiol divinyl ether, 1,4-cyclohexanedimethanol divinyl ether, and the like as divinyl ethers. One type or two or more types may be used in combination.

  Subsequently, the manufacturing method of the polyacetal compound (A) used by this invention is demonstrated. As a reaction method, as long as 10 to 100 mol% of the aromatic hydroxyl group in the polyhydroxy compound (a) to be used is acetalized, it is sufficient to follow the reaction conditions of the aromatic hydroxyl group and the vinyl ether group, Although not particularly limited, for example, a method in which a polyhydroxy compound (a) and an appropriate amount of vinyl ether are charged and heated while stirring and mixing can be mentioned. In this case, an organic solvent and a catalyst can be used as needed. The organic solvent that can be used is not particularly limited, and examples thereof include aromatic organic solvents such as benzene, toluene, and xylene, and ketone-based organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. A solvent containing an alcoholic hydroxyl group is not preferable because it reacts with vinyl ethers depending on conditions. These organic solvents may be appropriately selected in consideration of properties such as solubility of raw materials to be used and products, reaction conditions, economy, and the like. The amount of the organic solvent is preferably 5 to 500% by weight based on the raw material weight.

  Usually, this reaction proceeds sufficiently even in a catalyst-free system, but a catalyst may be used depending on the kind of raw material used, the desired characteristics of the resulting polyacetal compound (A), the desired reaction rate, and the like. The type of the catalyst is not particularly limited as long as it is a catalyst usually used for the reaction of a hydroxyl group and a vinyl ether group. For example, inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, toluenesulfonic acid, Methanesulfonic acid, xylenesulfonic acid, trifluoromethanesulfonic acid, oxalic acid, formic acid, trichloroacetic acid, trifluoroacetic acid and other organic acids, aluminum chloride, iron chloride, tin chloride, gallium chloride, titanium chloride, aluminum bromide, gallium bromide Lewis acids such as boron trifluoride ether complex and boron trifluoride phenol complex can be mentioned, but in view of the reaction rate improving effect and side reaction suppressing effect, phosphate esters are particularly preferable. Although it does not specifically limit as addition amount, It can use in the range of 10 ppm-1 weight% with respect to the raw material total weight. However, in the catalyst addition system, it is necessary to select the type, addition amount, and reaction conditions so as not to cause a vinyl group nucleus addition reaction to the aromatic ring.

  The reaction conditions are usually room temperature to 200 ° C., preferably 50 to 150 ° C., and may be heated and stirred for about 0.5 to 30 hours. At this time, in order to prevent the self-polymerization of vinyl ethers, the reaction in an oxygen-containing atmosphere is preferable. The progress of the reaction can be traced by measuring the residual amount of the raw material using gas chromatography, liquid chromatography or the like. Further, when an organic solvent is used, it is preferably removed by distillation or the like. When a catalyst is used, it is preferably deactivated with a deactivator or the like as necessary, and then removed by washing with water or filtering.

  The charging ratio of the polyhydroxy compound (a) and the vinyl ether in the above reaction is particularly limited as long as 10 to 100 mol% of the aromatic hydroxyl group in the polyhydroxy compound (A) can be finally acetalized. However, it is usually preferred that the vinyl ether group be used in a range of 0.1 to 3 moles per mole of the aromatic hydroxyl group in the polyhydroxy compound (a). If suitable reaction conditions are used, the desired acetalization rate can be achieved with a stoichiometric charge ratio.

  The epoxy resin (B) used in the present invention is not particularly limited, and any epoxy resin can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type Epoxy resin, resorcinol type epoxy resin, hydroquinone type epoxy resin, catechol type epoxy resin, dihydroxynaphthalene type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, triphenyl Methane type epoxy resin, tetraphenylethane type epoxy resin, dicyclopentadiene-phenol addition reaction type epoxy resin, phenol aralkyl type epoxy resin, naphtholno Rack type epoxy resin, naphthol aralkyl type epoxy resin, naphthol-phenol co-condensed novolac type epoxy resin, naphthol-cresol co-condensed novolac type epoxy resin, aromatic hydrocarbon formaldehyde resin modified phenolic resin type epoxy resin, biphenyl modified novolac type epoxy resin Tetrabromobisphenol A type epoxy resin, brominated phenol novolac type epoxy resin, alicyclic epoxy resin and the like. Moreover, an epoxy resin may be used independently and may mix 2 or more types.

  The epoxy resin composition of the present invention is not particularly limited to the above-described polyacetal compound (A) and the epoxy resin (B) as essential, but the workability and the like adapted to each application described later are provided. In order to give, it is preferable to use an organic solvent (C).

  As the organic solvent (C), the polyacetal compound (A) and the epoxy resin (B), and other curing agents, curing accelerators, various additives, etc., which are used in combination as necessary, are uniformly dissolved and dispersed. However, it is preferable to use a polar solvent having a boiling point of 160 ° C. or lower, such as methyl ethyl ketone, acetone, dimethylformamide or the like, which does not contain an alcoholic hydroxyl group. It can also be used as a mixed solvent of two or more kinds. A solvent containing an alcoholic hydroxyl group is not preferable because it reacts with vinyl ethers depending on conditions.

  In the epoxy resin composition of the present invention, the polyacetal compound (A) is used as a curing agent for the epoxy resin (B), but various other kinds are necessary as long as the effects of the present invention are not impaired. These curing agents can be used in combination.

  Although it does not specifically limit as a hardening | curing agent which can be used together, For example, an amine compound, an acid anhydride type compound, an amide type compound, a phenol type compound etc. are mentioned, As an amine type compound, ethylenediamine, propylenediamine, butylene is mentioned. Aliphatic polyamines such as diamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, pentaethylenehexamine, aromatic polyamines such as metaxylylenediamine, diaminodiphenylmethane, phenylenediamine, 1,3-bis (aminomethyl) cyclohexane, Examples thereof include alicyclic polyamines such as isophorone diamine and norbornane diamine, polyamide resins synthesized from dicyandiamide and a dimer of linolenic acid and ethylene diamine.

  Examples of the acid anhydride compound include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methyl nadic anhydride, hexahydrophthalic anhydride. And methyl hexahydrophthalic anhydride.

Examples of phenolic compounds include phenol novolak resins, cresol novolac resins, aromatic hydrocarbon formaldehyde resin-modified phenol resins, dicyclopentadiene phenol addition resins, phenol aralkyl resins, naphthol aralkyl resins, trimethylol methane resins, tetra Examples include phenylolethane resin, naphthol novolak resin, naphthol-phenol co-condensed novolak resin, naphthol-cresol co-condensed novolac resin, biphenyl-modified phenol resin, aminotriazine-modified phenol resin, and modified products thereof. Examples of the latent curing agent include imidazole, BF ₃ -amine complex, and guanidine derivative.

  Moreover, as these other hardening | curing agents, you may use independently and may mix 2 or more types.

  In the epoxy resin composition of the present invention, the amount of the curing agent used is such that curing proceeds smoothly and good physical properties of the cured product can be obtained, so that polyacetal is equivalent to 1 equivalent of epoxy group in the epoxy resin (B). When the total of the acetal group and the aromatic hydroxyl group in the compound (A) and other curing agents are used, the total of the active groups in the curing agent is 0.7 to 1.5 equivalents. Is preferred.

  Moreover, a hardening accelerator can also be further used for the epoxy resin composition of this invention suitably. Various curing accelerators can be used, and examples thereof include phosphorus compounds, tertiary amines, imidazoles, organic acid metal salts, Lewis acids, amine complex salts, and the like. Can be used in combination. For example, as a semiconductor encapsulating material, triphenylphosphine for phosphorus-based materials and 1,8-diazabicyclo- [5,4,0] -undecene (DBU) for amine-based materials have good curability and heat resistance. It is preferable because a cured product having excellent electrical characteristics and moisture resistance reliability can be obtained. The addition amount is not particularly limited, but is preferably in the range of 0.05 to 10% by weight with respect to the total amount of the epoxy resin and the curing agent.

  An inorganic filler can be blended in the epoxy resin composition of the present invention. Examples of the inorganic filler include fused silica, crystalline silica, alumina, silicon nitride, and aluminum hydroxide. When particularly increasing the blending amount of the inorganic filler, it is preferable to use fused silica. The fused silica can be used in either a crushed shape or a spherical shape. However, in order to increase the blending amount of the fused silica and suppress an increase in the melt viscosity of the molding material, it is preferable to mainly use a spherical shape. In order to further increase the blending amount of the spherical silica, it is preferable to appropriately adjust the particle size distribution of the spherical silica. The filling rate is preferably higher in consideration of flame retardancy, and particularly preferably 65% by weight or more with respect to the total amount of the epoxy resin composition. Moreover, when using for uses, such as an electrically conductive paste, electroconductive fillers, such as silver powder and copper powder, can be used.

  Various compounding agents, such as a silane coupling agent, a mold release agent, a pigment, an emulsifier, can be added to the epoxy resin composition of this invention as needed.

  A flame retardant imparting agent can be added to the epoxy resin composition of the present invention as necessary. Various flame retardants can be used, for example, halogen compounds such as decabromodiphenyl ether and tetrabromobisphenol A, phosphorus atom-containing compounds such as red phosphorus and various phosphoric acid ester compounds, melamine or derivatives thereof, etc. Inorganic flame retardant compounds such as nitrogen atom-containing compounds, aluminum hydroxide, magnesium hydroxide, zinc borate, calcium borate and the like can be mentioned.

  The epoxy resin composition of this invention is obtained by mixing each component uniformly. The epoxy resin composition of the present invention in which the epoxy resin of the present invention, a curing agent, and, if necessary, a curing accelerator are blended can be easily made into a cured product by various methods.

  The use of the epoxy resin composition of the present invention is not particularly limited, and for example, for printed circuit boards, electronic component sealing materials, resist inks, conductive pastes, resin casting materials, adhesives, and insulation. Examples thereof include coating materials such as paints, and among these, the cured product obtained has excellent dielectric properties and low moisture absorption properties, so that it is a resin composition for encapsulants for electronic components, a resin composition for printed circuit boards, and a resist. It can be suitably used for inks, conductive pastes, and interlayer insulating materials.

  For example, in order to prepare an epoxy resin composition for paints, use a disperser such as a paint shaker until a compound such as an epoxy resin, a curing agent, and if necessary, an organic solvent, a filler, and a pigment is uniform. The method of mixing is mentioned. Moreover, for powder coatings, it can be obtained by pulverizing a mixture obtained in the same manner as a semiconductor sealing material described later with a pulverizer or the like.

  In order to produce an epoxy resin composition for a semiconductor encapsulant, it is sufficient until the epoxy resin and a compounding agent such as a curing agent and a filler are uniform using an extruder, a kneader, a roll or the like as necessary. What is necessary is just to obtain a melt-mixing type epoxy resin composition by mixing them. At that time, silica is usually used as the filler, and the filling rate is preferably in the range of 30 to 95% by weight per 100 parts by weight of the epoxy resin composition. In order to improve moisture resistance and solder crack resistance and to reduce the linear expansion coefficient, it is particularly preferably 70 parts by weight or more, and in order to significantly increase these effects, 80 parts by weight or more further enhances the effect. be able to.

  As semiconductor package molding, the resin composition can be molded by casting, using a transfer molding machine, an injection molding machine or the like, and further heated at 50 to 200 ° C. for 2 to 10 hours to obtain a molded product. it can.

  Moreover, when using as a tape-shaped sealing material, after heating the resin composition obtained by the above-mentioned method and producing a semi-hardened sheet and using it as a sealing agent tape, this sealing agent tape is used as a semiconductor chip. Examples of the method include placing it on top, heating to 100 to 150 ° C, softening and molding, and completely curing at 170 to 250 ° C.

  Furthermore, when using as a potting type liquid sealing agent, the resin composition obtained by the above-mentioned method may be applied on a semiconductor chip or an electronic component and directly cured.

  Also, the method used as an underfill resin is not particularly limited, but it is described in JP-A-9-266221 and “Plastics in the Electronics Field” (published by Industrial Research Council, 1999, pages 27 to 34). The method can be adopted. More specifically, the epoxy resin composition of the present invention is injected into the gap between the semiconductor element with electrodes and the printed wiring board with solder during flip-chip mounting by a capillary flow method using a capillary phenomenon and cured. And a compression flow method in which the epoxy resin composition of the present invention is semi-cured on a substrate or a semiconductor element in advance, and then the semiconductor element and the substrate are brought into close contact with each other to be completely cured. In this case, the epoxy resin composition of the present invention is preferably used in the form of a liquid resin composition containing no organic solvent. In particular, when the capillary flow method is used, the viscosity needs to be low, and the viscosity is preferably 5000 mPa · s or less. If the said resin composition is a viscosity exceeding this, it can also inject | pour after heating to room temperature-100 degrees C or less.

  In order to make the epoxy resin composition of the present invention into a resin composition for a prepreg for a printed circuit board, it can be used without a solvent depending on the viscosity of the resin composition, but for prepreg by varnishing with an organic solvent. A resin composition is preferred. As the organic solvent, it is preferable to use a polar solvent having a boiling point of 160 ° C. or lower such as methyl ethyl ketone, acetone, dimethylformamide or the like which does not contain an alcoholic hydroxyl group, and it can be used alone or as a mixed solvent of two or more kinds. A solvent containing an alcoholic hydroxyl group is not preferable because it reacts with vinyl ethers depending on conditions. The obtained varnish is impregnated into various reinforcing substrates such as paper, glass cloth, glass nonwoven fabric, aramid paper, aramid cloth, glass mat, and glass roving cloth, and the heating temperature according to the solvent type used, preferably 50 By heating at ˜170 ° C., a prepreg that is a cured product can be obtained. The weight ratio of the resin composition and the reinforcing substrate used at this time is not particularly limited, but it is usually preferable that the resin content in the prepreg is adjusted to 20 to 60% by weight.

  In order to obtain a resin composition for a copper-clad laminate from the epoxy resin composition of the present invention, it is the same as the method for preparing the resin composition for prepreg, and the obtained prepreg is disclosed in, for example, JP-A-7-41543. A copper-clad laminate can be obtained by laminating as described, stacking copper foils as appropriate, and thermocompression bonding at 170-250 ° C. for 10 minutes to 3 hours under a pressure of 1-10 MPa.

  When the epoxy resin composition of the present invention is used as a resist ink, for example, according to the method described in JP-A No. 5-186567, a resist ink composition is prepared and then printed on a printed circuit board by a screen printing method. The method of making it a resist ink hardened | cured material after apply | coating to is mentioned.

  When using the epoxy resin composition of the present invention as a conductive paste, for example, fine conductive particles described in JP-A-3-46707 are dispersed in the resin composition, and the composition for anisotropic conductive film is used. And a paste resin composition for circuit connection which is liquid at room temperature as disclosed in JP-A-62-240183, JP-A-62-276215, JP-A-62-176139, etc. And an anisotropic conductive adhesive.

  When the epoxy resin composition of the present invention is used as a semiconductor interlayer insulating material, for example, the method described in JP-A-6-85091 can be employed. When used as an interlayer insulating film, it will be in direct contact with the semiconductor, so it is required that the linear expansion coefficient of the insulating material be close to the linear expansion coefficient of the semiconductor so that cracks due to the difference in linear expansion coefficient do not occur in a high temperature environment. The In addition, in order to deal with the problem of signal delay due to miniaturization, multilayering, and high density of semiconductors, there is a demand for technology for reducing the capacity of insulating materials, and this problem can be solved by reducing the dielectric of insulating materials. be able to. The resin composition is preferable because it has characteristics satisfying these requirements.

  Although it does not specifically limit as a method of obtaining the interlayer insulation material for buildup boards from the epoxy resin composition of the present invention, for example, Japanese Patent Publication No. 4-6116, Unexamined-Japanese-Patent No. 7-304931, Unexamined-Japanese-Patent No. 8-64960, Various methods described in JP-A-9-71762, JP-A-9-298369 and the like can be employed. More specifically, the resin composition appropriately blended with rubber, filler, and the like is applied to a wiring board on which a circuit is formed using a spray coating method, a curtain coating method, or the like, and then cured. Then, after drilling a predetermined through-hole part etc. as needed, it treats with a roughening agent, forms the unevenness | corrugation by washing the surface with hot water, and metal-treats, such as copper. As the plating method, electroless plating or electrolytic plating treatment is preferable, and examples of the roughening agent include an oxidizing agent, an alkali, and an organic solvent. Such operations are sequentially repeated as desired, and a build-up substrate can be obtained by alternately building up and forming the resin insulating layer and the conductor layer having a predetermined circuit pattern. However, the through-hole portion is formed after the outermost resin insulating layer is formed. In addition, a resin-coated copper foil obtained by semi-curing the resin composition on the copper foil is thermocompression-bonded at 170 to 250 ° C. on a circuit board on which a circuit is formed, thereby forming a roughened surface and plating treatment. It is also possible to produce a build-up substrate by omitting the process.

The epoxy resin composition of the present invention is thermally cured, molded product, laminate, cast material, adhesive, coating, it is possible to obtain a cured product having a form such as a film. For example, in the case of a melt-mixed type composition, the composition is molded by casting, using a transfer molding machine, an injection molding machine or the like, and further heated at 80 to 250 ° C. for 2 to 10 hours. A cured product can be obtained. In the case of a varnish-like composition, a coating film can be obtained by coating it on a substrate and drying it by heating, and the paint corresponds to this. In addition, it can be obtained by impregnating a substrate such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, paper, etc. and drying by heating to obtain a prepreg, which can be obtained by hot press molding This is the case for laminated materials for substrates and CFRP.

  Next, the present invention will be specifically described with reference to examples and comparative examples. “Parts” and “%” described below are based on weight unless otherwise specified.

  Synthesis Example 1 [Synthesis of polyacetal compound (A-1) of the following structural formula (a-1), acetalization rate of 100%]

（式中のｎは繰り返し数を表し、約３である。）

(In the formula, n represents the number of repetitions and is about 3.)

  Phenol novolak resin represented by the structural formula (a-1) on a flask equipped with a thermometer and a stirrer (Dainippon Ink Chemical Co., Ltd .; Phenolite TD-2131, amorphous compound having a softening point of 80 ° C., (Hydroxyl equivalent: 104 g / eq) 200 g, n-butyl vinyl ether 400 g and methyl isobutyl ketone 600 g were added, and 1 g of a phosphoric acid ester catalyst (manufactured by Daihachi Chemical; AP-8) was added thereto, followed by stirring at 80 ° C. and normal pressure for 10 hours. And reacted. Subsequently, unreacted n-butyl vinyl ether and methyl isobutyl ketone were recovered at that temperature under vacuum to obtain a viscous liquid target substance. Judging from the obtained material weight of 397 g and unreacted n-butyl vinyl ether weight of 201 g, it was estimated that substantially 100% of the hydroxyl groups were acetalized.

Synthesis Example 2 [Synthesis of Polyacetal Compound (A-2) of Structural Formula (a-1), Acetalization Rate 50%]
In Synthesis Example 1, the reaction was performed in the same manner as in Synthesis Example 1 except that the amount of n-butyl vinyl ether charged was changed to 100 g, to obtain 295 g of a semisolid target substance. Further, after the reaction was completed, the amount of unreacted n-butyl vinyl ether recovered was 0.5 g, so that it was estimated that about 50% of the hydroxyl groups in the raw material were acetalized.

  Synthesis Example 3 [Synthesis of polyacetal compound (A-3) of the following structural formula (a-3), acetalization rate of 100%]

  In Synthesis Example 1, the phenol novolak resin was added to 166 g of 1,1′-bis (2,7-dihydroxy) naphthylmethane (crystalline compound having a melting point of 274 ° C.) represented by the structural formula (a-3), and n-butyl vinyl ether. Was changed to 260 g in the same manner as in Synthesis Example 1 to obtain 339 g of viscous target substance. Since n-butyl vinyl ether distilled and recovered after completion of the reaction was 64 g, it was estimated that substantially 100% of the hydroxyl groups were acetalized.

  Synthesis Example 4 [Synthesis of Polyacetal Compound (A-4) of Structural Formula (a-4) below, Acetalization Rate of 100%]

  In Synthesis Example 1, except that the phenol novolak resin was changed to 199 g of 1,1 ′, 2,2′-tetraphenylolethane (crystalline compound having a melting point of 315 ° C.) represented by the structural formula (a-4), In the same manner as in Synthesis Example 1, 380 g of viscous target substance was obtained. Since 61 g of n-butyl vinyl ether recovered by distillation after the reaction was completed, it was estimated that substantially 100% of the hydroxyl group was acetalized.

  The four types of polyacetal compounds (A-1) to (A-4) thus obtained were converted into phenol novolak resins represented by the structural formula (a-1) [Phenolite TD-2131 manufactured by Dainippon Ink & Chemicals, Inc. Softening point 80 ° C., hydroxyl group equivalent 104 g / eq. Hereinafter referred to as (a-1). And 1,1′-bis (2,7-dihydroxy) naphthylmethane represented by the structural formula (a-3) which is a crystalline polyhydroxy compound [melting point: 274 ° C. crystalline compound, hydroxyl group equivalent: 83 g / eq . Hereinafter referred to as (a-3). And 1,1 ′, 2,2′-tetraphenylolethane represented by the structural formula (a-4) (a crystalline compound having a melting point of 315 ° C., a hydroxyl group equivalent of 100 g / eq. Hereinafter referred to as (a-4). .)). The appearance at room temperature (25 ° C.) is summarized in Table 1.

  Obviously from Table 1, it was confirmed that the polyacetal compound had a lower viscosity than the polyhydroxy compound used as a raw material and had good fluidity.

1) Solvent solubility evaluation of compounds Generality of polyacetal compounds (A-1) to (A-4) and polyhydroxy compounds (a-1), (a-3) and (a-4) obtained as described above The solubility evaluation with respect to methyl ethyl ketone (MEK) which is a solvent used for a typical epoxy resin composition varnish product, and toluene was performed. As a specific method, 100 parts of the above compound and 100 parts of the solvent are mixed, heated to 70 ° C., stirred and homogenized, and then visually observed when cooled to room temperature (25 ° C.). Thus, the solubility was evaluated. The results are shown in Table 2.

  As shown in Table 2, the crystalline compounds (a-3) and (a-4) were not dissolved in the solvent used for general epoxy resin varnish products, and a uniform composition could not be prepared. . On the other hand, all the polyacetal compounds (A-1) to (A-4) showed the same solubility as the phenol novolak resin (a-1) which is an amorphous curing agent, and a uniform composition could be prepared.

2) Compatibility evaluation with epoxy resin As epoxy resin (B), bisphenol A type liquid epoxy resin (Dainippon Ink & Chemicals, Inc .; EPICLON 850S, epoxy equivalent 188 g / eq) and cresol novolac type epoxy resin (Dainippon) Ink Chemical Industries, Ltd .; EPICLON N-665-EXP, epoxy equivalent 204 g / eq) was used for compatibility evaluation.

  Specifically, the polyacetal compounds (A-1) to (A-4) and polyhydroxy compounds (a-1), (a-3) and (a-4) obtained as described above and an epoxy resin (B ) Were mixed according to the blending ratios shown in Tables 3 to 4, heated to 80 ° C., and mixed by stirring to obtain an epoxy resin composition. Thereafter, compatibility was evaluated by observing the appearance of the composition when it was cooled to room temperature (25 ° C.).

  As shown in Tables 3 to 4, crystalline compounds (a-3) and (a-4) are incompatible with both bisphenol A type and cresol novolak type epoxy resins, and a uniform composition is prepared. could not. On the other hand, all the polyacetal compounds (A-1) to (A-4) showed the same compatibility as the phenol novolak resin (a-1) which is an amorphous curing agent, and a uniform composition could be prepared.

3) Evaluation of heat resistance of cured product As epoxy resin (B), EPICLON 850S and EPICLON N-665-EXP were used in the same manner as in the compatibility evaluation test, and 2-ethyl-4-methylimidazole was used as the curing accelerator. Using 2% by weight with respect to the whole, mixing was carried out at a blending ratio shown in Tables 5 to 6, to obtain an epoxy resin composition. The composition obtained was allowed to stand for 7 hours in a 200 ° C. hot-air circulating drier for a curing reaction, and the glass transition temperature was measured by a dynamic viscoelasticity measuring device (DMA) using the obtained test piece. Was measured. The results are shown in Tables 5-6.

  As shown in Tables 5 to 6, when polyacetal compounds (A-1) and (A-2) using phenol novolac resin (a-1) as a raw material were used as curing agents, phenol was used in either case. The glass transition temperature was similar to that of the novolak resin (a-1), no performance deterioration due to acetalization was observed, and it was confirmed that the curing reaction by deblocking was sufficiently advanced. In addition, when a crystalline compound (a-3) or (a-4), which has been lacking properly as a curing agent for an epoxy resin, is used as a raw material and the viscosity is reduced by polyacetalization, it is used as a curing agent. It was confirmed that a cured product having a glass transition temperature much higher than when a conventional phenol novolac resin was used as a curing agent was obtained.

Claims (9)

  10 to 100 mol% of the aromatic hydroxyl group in the polyhydroxy compound (a), which is a crystalline compound containing more than two aromatic hydroxyl groups in one molecule and having a melting point of 150 ° C. or higher, was acetalized. An epoxy resin composition comprising a polyacetal compound (A) and an epoxy resin (B).   The epoxy resin composition according to claim 1, wherein the crystalline compound is a tetravalent hydroxy compound. The epoxy resin composition according to claim 2, wherein the tetravalent hydroxy compound is a compound represented by the following formula (a-3) or (a-4).

  The epoxy resin composition according to claim 1, further comprising an organic solvent (C).   The epoxy resin composition of any one of Claims 1-4 prepared for the use of the resin composition for sealing materials of an electronic component.   The epoxy resin composition of any one of Claims 1-4 prepared for the use of the resin composition for printed circuit boards.   The epoxy resin composition according to claim 1, which is prepared for use as a resist ink.   The epoxy resin composition according to any one of claims 1 to 4, which is prepared for use as a conductive paste.   The epoxy resin composition according to any one of claims 1 to 4, which is prepared for use as an interlayer insulating material.