JP2013163719A - Low thermally-expandable resin composition, prepreg, laminate, and wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for a printed wiring board especially excellent in low thermal expansion without the need of high filling of an inorganic filler or enhanced crosslink density of the resin composition; and a prepreg, a laminate, and a wiring board using the same.SOLUTION: A low thermally-expandable resin composition includes an epoxy resin (A) having polycyclic structure, a phosphorus compound (B) represented by chemical formula (I), and dicyandiamide (C), wherein an epoxy resin (E1), which is obtained when 0.005-0.05 mol of the phosphorus compound (B) represented by chemical formula (I) is blended or preliminary reacted with 1 mol of an epoxy group of the epoxy resin (A) having polycyclic structure, is contained.

Description

  The present invention relates to a resin composition for a printed wiring board used for an electronic device, and particularly relates to a resin composition, a prepreg, a laminated board and a wiring board that are excellent in low thermal expansion.

  Printed wiring boards are becoming narrower in pitch with the downsizing and higher performance of electronic equipment. As a semiconductor mounting method for high-density wiring, a flip chip connection method is widely used instead of the conventional wire bonding method. Flip chip connection is a method in which a wiring board and a semiconductor are mounted with solder balls, and heat close to 300 ° C. is applied to the wiring board at the time of solder reflow, and in a wiring board made of a general resin composition, due to thermal expansion of the resin. Large stress is generated at the connection interface, which may cause connection failure. Against this background, a low thermal expansion laminate is demanded.

A typical laminate is generally obtained by curing and integrally molding a resin composition mainly composed of an epoxy resin and a glass woven fabric. Epoxy resins have an excellent balance of insulation, heat resistance, cost, etc., but have a large coefficient of thermal expansion. For this reason, it is common to add inorganic fillers, such as a silica, and to suppress thermal expansion (for example, refer patent document 1).
It is possible to further reduce the thermal expansion by filling the resin composition mainly composed of epoxy resin with an inorganic filler, but increasing the filling amount reduces the insulation reliability due to moisture absorption and the adhesion between the resin and the wiring layer. There is a limit in the use of multilayer wiring boards because of insufficiency.
Moreover, as a low thermal expansion pressure molding resin composition using an epoxy resin having an aromatic ring, there is one using an epoxy resin having a bifunctional naphthalene skeleton or a biphenyl skeleton (see, for example, Patent Document 2). . However, in patent document 2, the filler which consists of fused silica powder is mix | blended 80-92.5 volume%, and cannot be used as a wiring board material.

  Conventionally, a method for reducing the coefficient of thermal expansion of a resin composition for a wiring board is generally a technique of increasing the crosslink density and increasing the glass transition temperature to reduce the coefficient of thermal expansion (see, for example, Patent Documents 3 and 4). ). However, increasing the crosslinking density means shortening the molecular chain between the functional groups, and shortening the molecular chain more than a certain level lowers the reactivity and the resin strength. On the other hand, a technique for optimizing the crosslinking density to lower the thermal expansion coefficient has also been studied (see, for example, Patent Document 5).

JP 2004-182851 A JP 05-148343 A JP 2000-243864 A JP 2000-114727 A JP 2007-314782 A

  In view of the current situation, the object of the present invention is to provide a resin composition for a printed wiring board that is particularly excellent in low thermal expansion without increasing the filling of the inorganic filler and increasing the cross-linking density of the resin composition, and the use thereof. An object of the present invention is to provide a prepreg, a laminated board and a wiring board.

  As a result of earnest research to solve the above-mentioned problems, the present invention contains an epoxy resin having a polycyclic structure and a specific phosphorus compound or dicyandiamide, or contains an epoxy resin that has been pre-reacted, in particular, a coefficient of thermal expansion. It has been found that a material for a multilayer wiring board having a small size can be obtained at low cost, and the present invention has been completed. The present invention has been completed based on such findings.

  That is, the present invention provides the following low thermal expansion resin composition, prepreg, laminate and wiring board.

1. The epoxy resin (A) having a polycyclic structure, the phosphorus compound (B) represented by the chemical formula (I), and dicyandiamide (C) are contained in 1 mol of an epoxy group of the epoxy resin (A) having a polycyclic structure. On the other hand, the low thermal expansion resin composition characterized by containing the epoxy resin (E1) which the phosphorus compound (B) shown by Chemical formula (I) mix | blended or pre-reacted by 0.005-0.05 mol.

2. The low thermal expansion resin composition according to 1 above, wherein the epoxy resin (A) having a polycyclic structure is an epoxy resin having at least one structure selected from a biphenyl structure, a naphthalene structure, an anthracene structure, and a dihydroanthracene structure.
3. An epoxy resin (A) having a polycyclic structure is a biphenyl novolac type epoxy resin represented by the following general formula (II), an anthracene type epoxy resin represented by the general formula (III), or a general formula (IV) 2. The low thermal expansion resin composition as described in 2 above, which comprises at least one selected from dihydroanthracene type epoxy resins.

(式中、Ｒ¹〜Ｒ⁴は独立に水素原子又は炭素数１〜５のアルキル基を表し、ｎは１以上の整数である。)

(In the formula, R ^{1 to} R ⁴ independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and n is an integer of 1 or more.)

(式中、Ｒ¹〜Ｒ⁴は独立に水素原子又は炭素数１〜５のアルキル基を表す。)

(Wherein R ^{1 to} R ⁴ independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.)

(式中、Ｒ¹およびＲ²は独立に水素原子又は炭素数１〜５のアルキル基を表す。ｍは０〜６の整数、ｎは０〜４の整数である。)

(In the formula, R ¹ and R ² independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. M is an integer of 0 to 6, and n is an integer of 0 to 4.)

4). 3. The epoxy resin (A) having a polycyclic structure comprises the biphenyl novolac type epoxy resin represented by the general formula (II) and the dihydroanthracene type epoxy resin represented by the general formula (IV). Low thermal expansion resin composition.
5. A prepreg characterized in that the low thermal expansion resin composition of any one of (1) to (4) is impregnated or coated in a sheet-like reinforcing base material and then B-staged.
6). The prepreg according to 5 above, wherein the sheet-like reinforcing base material is at least one selected from a glass woven fabric, a glass nonwoven fabric, and an aramid nonwoven fabric.
7). A laminate having an insulating resin layer formed using the resin composition of any one of 1 to 4 or the prepreg of 5 or 6 above.
8). 8. A wiring board obtained by subjecting a metal foil disposed on one or both sides of an insulating resin layer in the laminated board of 7 to circuit processing.

  In the low thermal expansion resin composition of the present invention, the thermal expansion coefficient can be easily reduced at low cost without increasing the filling of the inorganic filler and increasing the crosslinking density of the resin composition. High-density wiring is achieved by using the resin layer.

The low thermal expansion resin composition of the present invention contains an epoxy resin (A) having a polycyclic structure, a phosphorus compound (B) represented by the general formula (I) and dicyandiamide (C), and has a polycyclic structure. The phosphorus compound (B) represented by the chemical formula (I) contains the epoxy resin (E1) blended or pre-reacted at 0.005 to 0.05 mol with respect to 1 mol of the epoxy group of the epoxy resin (A) having It is characterized by this.
Next, each component of the low thermal expansion resin composition of the present invention (hereinafter also simply referred to as “resin composition”) will be described.

  First, the epoxy resin having a polycyclic structure as the component (A) in the epoxy resin (E1) to be contained in the low thermal expansion resin composition of the present invention has two or more epoxy groups and a polycyclic structure in the molecule. Examples thereof include naphthalene type epoxy resins, naphthalene novolac type epoxy resins, anthracene type epoxy resins, dihydroanthracene type epoxy resins, biphenyl type epoxy resins, and biphenyl novolac type epoxy resins. The molecular weight of these compounds is not particularly limited, and two or more kinds can be used in combination.

Moreover, it is preferable that (A) component is an epoxy resin which has at least 1 sort (s) chosen from the biphenyl structure, the naphthalene structure, the anthracene structure, and the dihydroanthracene structure among the epoxy resins which have said polycyclic structure.
The component (A) includes a biphenyl novolac type epoxy resin represented by the following general formula (II), an anthracene type epoxy resin represented by the general formula (III), and a dihydroanthracene represented by the general formula (IV) It is more preferable that it contains at least one epoxy resin selected from type epoxy resins.
Further, the component (A) particularly preferably contains a biphenyl novolac type epoxy resin represented by the general formula (II) and a dihydroanthracene type epoxy resin represented by the general formula (IV).

(式中、Ｒ¹〜Ｒ⁴は独立に水素原子又は炭素数１〜６のアルキル基を表し、ｎは1以上の整数である。)

(Wherein R ^{1 to} R ⁴ independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and n is an integer of 1 or more.)

(式中、Ｒ¹〜Ｒ⁴は独立に水素原子又は炭素数１〜６のアルキル基を表す。)

(In the formula, R ^{1 to} R ⁴ independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.)

(式中、Ｒ¹およびＲ²は独立に水素原子又は炭素数１〜６のアルキル基を表す。ｍは０〜６の整数、ｎは０〜４の整数である。)

(In the formula, R ¹ and R ² independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. M is an integer of 0 to 6, and n is an integer of 0 to 4.)

  Next, the component (B) in the epoxy resin (E1) contained in the resin composition of the present invention includes a phosphorus compound [10- (2,5-dihydroxyphenyl) -10-H represented by the chemical formula (I). -9-oxa-10-phosphaphenanthrene-10-oxide]. The phosphorus compound represented by the chemical formula (I) is sold by Sanko Co., Ltd. under the trade name “HCA-HQ”.

The epoxy resin (E1) contained in the resin composition of the present invention further contains dicyandiamide as the component (C).
The epoxy resin (E1) contained in the resin composition of the present invention includes a curing agent (D) and a curing accelerator (E) other than the phosphorus compound (B) and dicyandiamide (C) represented by the general formula (I). ) May be included.
The curing agent (D) may be any one as long as it has a functional group having reactivity with two or more epoxy groups in the molecule, such as an acid anhydride, an amine compound, a phenol compound, and the like. Raised. Examples of amine compounds include guanamine resins, melamine resins, triethylenetetramine, aminotriazine novolac resins, and the like. Examples of the phenolic compound include naphthalene diol, phenol novolak resin, cresol novolak resin, bisphenol A type novolak resin, aminotriazine novolak resin, bismaleimide-containing aminotriazine novolak resin, bisphenol A, and bisphenol F. These compounds may have any molecular weight, and several types may be used in combination.
Examples of the curing accelerator (E) include imidazoles and derivatives thereof, tertiary amines and quaternary ammonium salts.

The compounding quantity of the phosphorus compound (B) shown by general formula (I) is 0.005-0.05 mol with respect to 1 mol of epoxy resin (A) which has a polycyclic structure, and is 0.0075-0. 05 mol is more preferable, and 0.01 to 0.05 is particularly preferable. When the compounding amount of the phosphorus compound (B) represented by the chemical formula (I) is less than 0.005 mol, the effect of reducing the thermal expansion coefficient does not appear, and also when the amount is more than 0.05 mol, the effect of reducing the thermal expansion coefficient Does not develop.
The compounding amount of the phosphorus compound (B), dicyandiamide (C) and curing agent (D) is such that the total amount of the components (B) to (D) is 0 with respect to 1 mol of the epoxy resin (A) having a polycyclic structure. It is preferable to set it as 0.01-20 mol, and it is more preferable to set it as 0.1-10 mol. By setting it as 0.01 mol or more, the reactivity of a phosphorus compound (B), dicyandiamide (C), a hardening | curing agent (D), and an epoxy resin improves.

The epoxy resin (E1) in the resin composition of the present invention is an epoxy resin containing the epoxy resin (A) having the above polycyclic structure, the phosphorus compound (B) represented by the chemical formula (I), and dicyandiamide (C). It may be a simple blend of (A) to (C), but storage stability is improved without performing crystallization by carrying out a preliminary reaction. preferable.
When the preliminary reaction is performed, the dicyandiamide (C) may be added in its entirety in the preliminary reaction, or a part thereof may be added after the preliminary reaction. Moreover, you may add other hardening | curing agents (D) with the phosphorus compound (B) and dicyandiamide (C) shown by chemical formula (I) by preliminary reaction. At this time, the total amount of the phosphorus compound (B) represented by the chemical formula (I), dicyandiamide (C), and the other curing agent (D) is based on the equivalent of the epoxy resin (A) having a polycyclic structure. 0.05 to 20 equivalents, preferably 0.1 to 10 equivalents. By setting it as 0.05-20 equivalent with respect to the equivalent of the epoxy resin which has a polycyclic structure, the solubility of the epoxy resin which has a polycyclic structure does not become inadequate. Moreover, 0.01-100 equivalent is preferable with respect to phosphorus compound (B) and hardening | curing agent (D), 0.01-100 equivalent is more preferable, 0.03-30 equivalent is more preferable, 0.05-20 equivalent is 0.05-20 equivalent. Further preferred. By setting it as 0.01-100 equivalent, it is possible to improve the solubility of an epoxy resin (A).
In the preliminary reaction, the epoxy resin (A) having a polycyclic structure can be used in combination with another epoxy resin, and the phosphorus compound (B), dicyandiamide (C) represented by the chemical formula (I), and others The total of the equivalents of the curing agent (D) of the epoxy is 0.8 to 1.2 times the total of the equivalents of the epoxy resin further used in combination with the epoxy resin (A) having a polycyclic structure. It is preferable to adjust the compounding ratio of the resin and the curing agent.

When the epoxy resin (A) having a polycyclic structure, the phosphorus compound (B) represented by the chemical formula (I) and the dicyandiamide (C) are pre-reacted, it is preferable to add a solvent.
As the solvent, the epoxy resin (A) having a polycyclic structure, the phosphorus compound (B) represented by the chemical formula (I) and the dicyandiamide (C) can be dissolved at the temperature of the preliminary reaction, and even after the preliminary reaction is completed, the solvent can be returned to room temperature. Any resin may be used as long as the resin does not precipitate from the varnish, but in particular acetone, methyl ethyl ketone, methyl butyl ketone, toluene, xylene, ethyl acetate, N, N-dimethylformamide, N, N-dimethylacetamide, ethanol, ethylene glycol Monomethyl ether, propylene glycol monomethyl ether acetate, and the like are preferable because of excellent solubility. These solvents may be used in combination.
The blending amount of the solvent is any amount as long as the resin composition in which the epoxy compound (A) having a polycyclic structure, the phosphorus compound (B) represented by the chemical formula (I) and the dicyandiamide (C) are pre-reacted can be dissolved. However, the range of 5 to 300 parts by mass is preferable with respect to 100 parts by mass of the total amount of the pre-reacted resin composition, and the range of 30 to 200 parts by mass is more preferable.
The temperature of the preliminary reaction is preferably 80 to 250 ° C, more preferably 88 to 245 ° C, and still more preferably 90 to 240 ° C. The reaction time is preferably 10 minutes to 30 hours, more preferably 30 minutes to 20 hours, and even more preferably 1 hour to 15 hours. By setting the preliminary reaction and the reaction time in such a range, the preliminary reaction proceeds sufficiently, the precipitation of the epoxy resin hardly occurs, and the handling of the resin composition becomes easy.

An inorganic filler can be blended in the low thermal expansion resin composition of the present invention. As the inorganic filler, silica, alumina, aluminum hydroxide, calcium carbonate, clay, talc, silicon nitride, boron nitride, titanium oxide, barium titanate, lead titanate, strontium titanate and the like can be used.
The blending amount of the inorganic filler should be 300 parts by mass or less with respect to 100 parts by mass of the total resin component in order that the resin composition of the present invention can obtain a uniform and good handling property as a multilayer wiring board material. Is preferable, and it is more preferable to make it 200 mass parts or less.

Moreover, you may add an additive to the low thermal expansion resin composition of this invention. As the additive, various silane coupling agents, curing accelerators, antifoaming agents and the like can be used.
In order to maintain the characteristics of the resin composition, the amount of the additive is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, with respect to 100 parts by mass of the total resin component.
In order to disperse the inorganic filler and additives uniformly, it is effective to use a raking machine, a homogenizer, or the like.

The prepreg of the present invention is obtained by impregnating or coating the low thermal expansion resin composition of the present invention on a sheet-like reinforcing base material and then forming a B stage.
As the prepreg sheet-like reinforcing substrate, known materials used in various laminated sheets for electrical insulating materials can be used, and glass woven fabric, glass nonwoven fabric, and aramid nonwoven fabric are preferably used. The thickness of the sheet-like reinforcing base material is not particularly limited, and for example, about 0.03 to 0.5 mm can be used, and the amount of the resin composition attached to the base material is the resin of the prepreg after drying. After impregnating or coating the base material so that the content is 20 to 90% by mass, it is usually heat-dried at a temperature of 100 to 200 ° C. for 1 to 30 minutes and semi-cured (B stage). The prepreg of the present invention can be obtained.

The laminated board of this invention has the insulating resin layer obtained by carrying out lamination molding using the above-mentioned low thermal expansion resin composition or prepreg. As a specific example of a laminated board, it can manufacture by laminating | molding by the structure which piled 1-20 sheets of prepregs, and has arrange | positioned metal foil, such as copper and aluminum, on the single side | surface or both surfaces, for example. The metal foil is not particularly limited as long as it is used for electrical insulating material applications.
The molding conditions can be applied to a laminate for an electrical insulating material and a multilayer board, for example, using a multistage press, a multistage vacuum press, continuous molding, an autoclave molding machine, etc., at a temperature of 100 to 250 ° C., a pressure of 0.2 to It can be molded in a range of 10 MPa and a heating time of 0.1 to 5 hours.
Further, the prepreg of the present invention and the inner layer wiring board can be combined and laminated to produce a multilayer board.
The wiring board of the present invention is obtained by subjecting a metal foil disposed on one or both sides of an insulating resin layer in a laminate to circuit processing, and is obtained by subjecting the above-mentioned laminate to general circuit processing. Can do.

EXAMPLES Next, although an Example demonstrates this invention in more detail, this invention is not limited to these description. In addition, the performance of the copper clad laminated board obtained by each Example and the comparative example measured and evaluated the glass transition temperature (Tg) and the thermal expansion coefficient ((alpha) ₁ , (alpha) ₂ ) with the following method.

That is, the copper clad laminate was immersed in an aqueous solution of 150 g / liter ammonium persulfate at 40 ° C. for 20 minutes to remove the copper foil by etching. Thereafter, a sample was cut out to 4 × 20 mm, and the primary heating was performed at a heating rate of 10 ° C./min and a measurement temperature range: room temperature to 220 by a tensile method (load 5 g) using a TMA test apparatus (manufactured by DuPont, TMA2940). Secondary heating is measured at a temperature rate of 10 ° C./min and a measurement temperature range: room temperature to 260 ° C., and the inflection point at the time of secondary heating is the glass transition temperature (Tg), and 50 to 120 ° C. The thermal expansion coefficient (α ₁ ) was measured from the average of the thermal expansion coefficients, and the thermal expansion coefficient (α ₂ ) was measured from the average of the thermal expansion coefficients of 200 to 250 ° C.

Example 1
In a four-neck separable flask equipped with a thermometer, a condenser, and a stirrer, 200 g of dihydroanthracene type epoxy resin (trade name YX-8800, manufactured by Japan Epoxy Resin Co., Ltd.) and biphenyl novolac type epoxy resin as component (A) (Nippon Kayaku Co., Ltd., trade name NC-3000-H) 165 g, (B) component phosphorus compound of formula (I) (Sanko Co., Ltd., trade name HCA-HQ) 5.5 g, (C) component dicyandiamide 3.4 g (manufactured by Kanto Chemical Co., Ltd.), 37.4 g of cresol novolak resin (Dainippon Ink Chemical Co., Ltd., trade name KA-1165) as component (D), propylene glycol monomethyl ether acetate (Kanto Chemical Co., Ltd.) as solvent 161 g) was added and pre-reacted at 140 ° C. for 3 hours.
After the preliminary reaction, 132 g of cresol novolac resin (Dainippon Ink Chemical Co., Ltd., trade name KA-1165) and 133 g of propylene glycol monomethyl ether acetate (manufactured by Kanto Chemical Co., Ltd.) were added and dissolved by heating at 100 ° C. for 30 minutes. . After dissolution, 0.4 g of 1-cyanoethyl-2-phenylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name 2PZ-CN), 170 g of silica (manufactured by Admatechs Co., Ltd., trade name SO-G1) as an accelerator, aluminum hydroxide 562 g (manufactured by Showa Denko KK, trade name HP-350) and 253 g of methyl isobutyl ketone (manufactured by Kanto Chemical Co., Inc.) were added and stirred at room temperature for 1 hour to prepare a varnish. The blending amount of the phosphorus compound represented by the chemical formula (I) of the component (B) is 0.01 mol with respect to 1 mol of the epoxy group of the epoxy resin having a polycyclic structure of the component (A).
Next, the obtained varnish was impregnated into a glass woven fabric having a thickness of 0.1 mm (basis weight 105 g / m ² ) and heated at 160 ° C. for 5 minutes to obtain a semi-cured (B stage state) prepreg. Two sheets of this prepreg are stacked, and 18 μm copper foil (made by Furukawa Electric, trade name F2-WS, Rz: 2.0 μm, Ra: 0.3 μm) is stacked on both sides thereof, 185 ° C., 90 minutes, 3.0 MPa. A double-sided copper-clad laminate was produced under pressing conditions. The performance measurement and evaluation results of the obtained copper-clad laminate are shown in Table 1.

Example 2
Preliminary using 13.8 g of phosphorus compound (HCA-HQ) of chemical formula (I) as component (B), 31.4 g of cresol novolac resin (KA-1165) as component (D), and 156 g of propylene glycol monomethyl ether acetate as solvent. The reaction was carried out, and 131 g of cresol novolak resin (KA-1165), 140 g of propylene glycol monomethyl ether acetate, 171 g of silica (SO-G1), 564 g of aluminum hydroxide (HP-350) and 253 g of methyl isobutyl ketone were added after the preliminary reaction. A varnish was produced in the same manner as in Example 1 except that a double-sided copper-clad laminate was produced. The compounding amount of the phosphorus compound represented by the chemical formula (I) of the component (C) is 0.025 mol with respect to 1 mol of the epoxy group of the epoxy resin having a polycyclic structure of the component (A). The performance measurement and evaluation results of the obtained copper-clad laminate are shown in Table 1.

Example 3
(B) 27.0 g of the phosphorus compound of formula (I) (HCA-HQ) as component, 21.6 g of cresol novolac resin (KA-1165) as component (D), and 150 g of propylene glycol monomethyl ether acetate as solvent The reaction is performed and changed to 131 g of cresol novolak resin (KA-1165), propylene glycol monomethyl ether acetate 151 g, silica (SO-G1) 172 g, aluminum hydroxide (HP-350) 568 g, and methyl isobutyl ketone 252 g. A varnish was prepared in the same manner as in Example 1 except that a double-sided copper-clad laminate was prepared. (B) The compounding quantity of the phosphorus compound shown by chemical formula (I) is 0.049 mol with respect to 1 mol of epoxy groups of the epoxy resin having a polycyclic structure of component (A). The performance measurement and evaluation results of the obtained copper-clad laminate are shown in Table 1.

Comparative Example 1
In a four-necked separable flask equipped with a thermometer, a condenser, and a stirrer, 200 g of dihydroanthracene type epoxy resin (YX-8800), 165 g of biphenyl novolac type epoxy resin (NC-3000-H), dicyandiamide 3 as a curing agent 4 g, 41.5 g of cresol novolak resin (KA-1165) and 163 g of propylene glycol monomethyl ether acetate as a solvent were added and pre-reacted at 140 ° C. for 3 hours.
Thereafter, 131 g of cresol novolac resin (KA-1165) and 161 g of propylene glycol monomethyl ether acetate were added and dissolved by heating at 100 ° C. for 30 minutes. After dissolution, 2PZ-CN: 0.4 g, silica (SO-G1) 170 g, aluminum hydroxide (HP-350) 561 g, and methyl isobutyl ketone 254 g are added as curing accelerators, and stirred at room temperature for 1 hour to produce a varnish. did. A double-sided copper-clad laminate was prepared in the same manner as in Example 1, and the performance measurement / evaluation results of the obtained copper-clad laminate are shown in Table 1.

Comparative Example 2
Preliminary reaction is carried out using 41.3 g of the phosphorus compound of formula (I) (HCA-HQ) as a curing agent, 26.3 g of cresol novolak resin (KA-1165), and 144 g of propylene glycol monomethyl ether acetate as a solvent. Example 1 was repeated except that 131 g of cresol novolak resin (KA-1165), 151 g of propylene glycol monomethyl ether acetate, 173 g of silica (SO-G1), 572 g of aluminum hydroxide (HP-350), and 248 g of methyl isobutyl ketone were used. To prepare a varnish and a double-sided copper-clad laminate. The blending amount of the phosphorus compound represented by the chemical formula (I) of the component (B) is 0.075 mol with respect to 1 mol of the epoxy group of the epoxy resin having a polycyclic structure of the component (A). The performance measurement and evaluation results of the obtained copper-clad laminate are shown in Table 1.

Comparative Example 3
Preliminary reaction is performed without using dicyandiamide as a curing agent, using 27 g of phosphorus compound of formula (I) (HCA-HQ), 40.9 g of cresol novolac resin (KA-1165), and 142 g of propylene glycol monomethyl ether acetate as a solvent. Comparative Example, except that 161 g of cresol novolak resin (KA-1165), 158 g of propylene glycol monomethyl ether acetate, 173 g of silica (SO-G1), 572 g of aluminum hydroxide (HP-350), 275 g of methyl isobutyl ketone were added after the preliminary reaction. The procedure was the same as in Example 1, but the resin was deposited and a copper clad laminate could not be produced.

Comparative Example 4
A varnish was prepared in the same manner as in Comparative Example 3 except that 0.2 g of the curing accelerator 2PZ-CN was added during the preliminary reaction and 0.2 g was added after the preliminary reaction. A double-sided copper-clad laminate was prepared in the same manner as in Example 1, and the performance measurement / evaluation results of the obtained copper-clad laminate are shown in Table 1.

Comparative Example 5
In a flask, phenol novolac type epoxy resin (DIC Corporation, trade name N-770) 200 g, dicyandiamide 2.2 g and cresol novolac resin (KA-1165) 113 g, propylene glycol monomethyl ether acetate 170 g, methyl isobutyl ketone 156 g as a solvent. Was stirred and dissolved at room temperature for 2 hours. Thereafter, 0.2 g of 2PZ-CN, 101 g of silica (SO-G1), and 343 g of aluminum hydroxide (HP-350) were added as curing accelerators, and stirred at room temperature for 1 hour to prepare a varnish. A double-sided copper-clad laminate was produced in the same manner as in Example 1, and the performance measurement / evaluation results of the copper-clad laminate are shown in Table 1.

Comparative Example 6
200 g of phenol novolac type epoxy resin (N-770) as an epoxy resin, 16.8 g of phosphorus compound of formula (I) (HCA-HQ) as a curing agent, 12.8 g of cresol novolak resin (KA-1165), and propylene glycol as a solvent Preliminary reaction is performed using 143 g of monomethyl ether acetate, and 88 g of cresol novolac resin (KA-1165) added after the preliminary reaction, 29 g of propylene glycol monomethyl ether acetate, 104 g of silica (SO-G1), 365 g of aluminum hydroxide (HP-350) A varnish was prepared in the same manner as in Comparative Example 1 except that 166 g of methyl isobutyl ketone was used. A double-sided copper-clad laminate was produced in the same manner as in Example 1, and the performance measurement / evaluation results of the copper-clad laminate are shown in Table 1.

From Table 1, the thermal expansion coefficient α ₁ of Examples 1 to 3 is 12 ppm / K or less, whereas the thermal expansion coefficient α ₁ of Comparative Examples 1 to 6 is as high as 13 ppm / K or more. Since the rate α _{2 is} also lower in Examples 1 to 3 than in the comparative example, it can be seen that the resin composition of the present invention has excellent low thermal expansion.
Comparative Example 3 does not contain dicyandiamide, and the sample was not able to be produced because the resin was precipitated. Therefore, the epoxy resin (A) having a polycyclic structure, the phosphorus compound (B) represented by the chemical formula (I), and dicyandiamide (C) are essential for the resin composition of the present invention, and even one is missing. It turns out that the function does not express.
Moreover, since the inorganic filler in the resin composition in the Example of this invention is less than 70 mass%, and the glass transition temperature is less than 200 degreeC, the low thermal expansion resin composition of this invention is the high filling of an inorganic filler. It turns out that it is not what increased the crosslink density of the resin composition or the resin composition.

  According to the present invention, it is possible to reduce the thermal expansion coefficient at low cost without increasing the filling of the inorganic filler and increasing the crosslinking density of the resin composition, and the high density of the wiring board is achieved. It is easy to downsize equipment.

Claims (8)

The epoxy resin (A) having a polycyclic structure, the phosphorus compound (B) represented by the chemical formula (I), and dicyandiamide (C) are contained in 1 mol of an epoxy group of the epoxy resin (A) having a polycyclic structure. On the other hand, the low thermal expansion resin composition characterized by containing the epoxy resin (E1) which the phosphorus compound (B) shown by Chemical formula (I) mix | blended or pre-reacted by 0.005-0.05 mol.

  The low thermal expansion resin composition according to claim 1, wherein the epoxy resin (A) having a polycyclic structure is an epoxy resin having at least one structure selected from a biphenyl structure, a naphthalene structure, an anthracene structure, and a dihydroanthracene structure. object. An epoxy resin (A) having a polycyclic structure is a biphenyl novolac type epoxy resin represented by the following general formula (II), an anthracene type epoxy resin represented by the general formula (III), or a general formula (IV) The low thermal expansion resin composition according to claim 2, comprising at least one selected from dihydroanthracene-type epoxy resins.

(In the formula, R ^{1 to} R ⁴ independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and n is an integer of 1 or more.)

(Wherein R ^{1 to} R ⁴ independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.)

(In the formula, R ¹ and R ² independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. M is an integer of 0 to 6, and n is an integer of 0 to 4.)   The epoxy resin (A) having a polycyclic structure contains a biphenyl novolac type epoxy resin represented by the general formula (II) and a dihydroanthracene type epoxy resin represented by the general formula (IV). 2. A low thermal expansion resin composition as described in 1. above.   A prepreg characterized in that the low thermal expansion resin composition according to any one of claims 1 to 4 is impregnated or coated in a sheet-like reinforcing base material and then B-staged.   The prepreg according to claim 5, wherein the sheet-like reinforcing base material is at least one selected from a glass woven fabric, a glass nonwoven fabric, and an aramid nonwoven fabric.   A laminated board comprising an insulating resin layer formed using the low thermal expansion resin composition according to any one of claims 1 to 4 or the prepreg according to claim 5 or 6.   The wiring board obtained by carrying out circuit processing of the metal foil arrange | positioned at the single side | surface or both surfaces of the insulating resin layer in the laminated board of Claim 7.