JP2001207020A - Epoxy resin composition for wiring board, prepreg for wiring board, and metal foil lined laminate board using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition greatly reduced in dusting and improved in machinability and handleability, useful suitably for wiring boards, a prepreg using the same, and to provide a metal foil lined laminate board using the same. SOLUTION: The epoxy resin composition for printed wiring boards essentially contains (a) a macromolecular resin which is a copolymer having a weight- average molecular weight of 200,000 to 1,500,000 and essentially containing an acrylic ester, (b) an epoxy resin, and (c) a curing agent. The prepreg for wiring boards is manufactured by impregnating glass woven fabric or glass nonwoven fabric with the epoxy resin composition for B-staging. The metal foil lined laminate board is fabricated by molding under heat and pressure a sheet of the prepreg or a laminate of two or more of the same and provided with metal foil on one or both sides.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an epoxy resin composition for a wiring board, a prepreg for a wiring board, and a metal foil-clad laminate using the same.

[0002]

2. Description of the Related Art Epoxy laminates are manufactured by impregnating a woven glass or nonwoven glass fabric with a varnish solution of an epoxy resin composition, drying and drying a B-staged prepreg, and applying heat and pressure. The epoxy resin composition is obtained by blending a curing agent and a curing accelerator with an epoxy resin having an epoxy equivalent of about 150 to 1000, and blending a flame retardant and a filler as necessary.

[0003] In many cases, glass woven fabric or glass non-woven fabric is used in the form of a roll. As a result, a prepreg is also manufactured in the form of a roll and then cut into a predetermined size to be used in the next manufacturing process of a laminated board. Is done.

[0004]

However, conventional epoxy resin prepregs generate a large amount of dust from the cut surface and surface during cutting and before lamination, and resin powder is generated when forming a metal foil-clad laminate. Adhesion to the metal foil surface tends to cause dent defects. As a countermeasure, there is a method in which the prepreg is reheated after cutting the prepreg to fuse the adhered powder.However, by reheating, the curing reaction of the prepreg progresses, and the prepreg characteristics change. Heated prepregs also have disadvantages such as rubbing during transportation and re-dusting, and cannot be said to be a definitive solution. In addition, the production efficiency decreases due to the increase in the number of steps.

SUMMARY OF THE INVENTION An object of the present invention is to provide an epoxy resin composition suitable for wiring boards which has extremely reduced dusting properties and has improved workability and handleability, a prepreg and a metal foil-clad laminate using the same. To provide.

[0006]

The present invention relates to the following. (1) (a) A high molecular weight resin which is a copolymer having a weight average molecular weight of 200,000 to 1,500,000 and an acrylate ester as an essential component, (b) an epoxy resin and (c) a curing agent are blended as essential components. Epoxy resin composition for printed wiring boards. (2) The epoxy resin composition for a printed wiring board according to item (1), wherein the high molecular weight resin of (a) is contained in an amount of 10 to 30% by weight based on the total amount of resin solids. (3) The epoxy resin composition for a printed wiring board according to item (1) or (2), wherein the high molecular weight resin (a) is a copolymer containing butyl acrylate and acrylonitrile as essential components. (4) A prepreg for a printed wiring board obtained by impregnating the epoxy resin composition for a wiring board according to any one of the above items (1) to (3) into a glass woven fabric or a glass nonwoven fabric to form a B stage. (5) A metal foil-clad laminate obtained by disposing a metal foil on one or both sides of a prepreg for a printed wiring board according to the item (4) or a laminate obtained by laminating two or more of the prepregs and heating and pressing the same.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The high molecular weight resin (a) is a polymer or a copolymer containing an acrylate ester as a main component, and the high molecular weight resin having a weight average molecular weight of 200,000 to 1.5 million is limited. Not done. It is preferable to use a resin which has a completely saturated structure in terms of chemical structure, does not cause a decrease in strength due to oxidation, embrittlement, aging and the like, and has tackiness and adhesiveness. Such a high molecular weight resin is generally known as an acrylic rubber and can be easily obtained. By mixing such a high-molecular-weight resin in the varnish, it plays a role of preventing adhesion of the prepreg resin and forming a film to prevent dust generation. The above weight average molecular weight can be measured by gel permeation chromatography using a standard polystyrene calibration curve.

[0008] The acrylate constituting the high molecular weight resin may be any acrylate, such as methyl acrylate, ethyl acrylate, butyl acrylate, and the like.
1 carbon atoms such as ethyl methacrylate and butyl methacrylate
Acrylic acid alkyl esters having ８8 alkyl groups are preferably used. High molecular weight resins containing two or more of these resins as structural components in the structure can also be used.

When a resin having a reactive group (functional group) is used as a high molecular weight resin, the compatibility of the resin with an epoxy resin or a curing agent in a varnish solution is improved. By cross-linking with the above resin, the adhesiveness and the film strength are improved, and the properties of the cured substrate can be improved, which is preferable. In order to provide a reactive group to a high molecular weight resin, unsaturated carboxylic acids such as acrylic acid and methacrylic acid, unsaturated monomers having a cyano group such as acrylonitrile, and glycidyl such as glycidyl acrylate and glycidyl methacrylate are contained. Unsaturated monomers and unsaturated monomers having a hydroxyl group such as hydroxyethyl methacrylate can be copolymerized with acrylic esters. The proportion of the unsaturated monomer having such a functional group is preferably from 0.1 to 40% by weight, more preferably from 5 to 30% by weight, based on the total amount of the monomer.

The amount of the high molecular weight resin is preferably 10 to 30% by weight based on the total resin solid content of the epoxy resin composition in order to obtain good prepreg characteristics.
-25% by weight is more preferred. If the compounding amount is too small from this range, the effect of preventing dust generation from the prepreg tends to decrease, and if too large, the viscosity of the epoxy resin composition tends to increase and moldability tends to decrease, Further, there is a tendency that laminate properties such as heat resistance of the laminate and deterioration of glass transition temperature (Tg) are lowered.

As the epoxy resin (b), a compound having two or more epoxy groups in a molecule is used.
For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, polyfunctional phenol diphenol There are glycidyl ether compounds, diglycidyl ether compounds of polyfunctional alcohols, halides thereof, hydrogenated products thereof, and the like, and some of them can be used in combination. The mixing amount of the epoxy resin is preferably from 10 to 85% by weight based on the total resin solid content of the epoxy resin composition.

(C) As the curing agent, those known as curing agents for epoxy resins can be used. For example, amines, phenolic compounds, phenolic resins, acid anhydrides and the like can be mentioned, but there is no particular limitation as long as they are generally used for an electrically insulating varnish. The amount of the curing agent is 5 to 8 with respect to the total resin solid content of the epoxy resin composition.
0% by weight is preferred.

Examples of the amines include diethylamine, diethylenetriamine, triethylenetetramine, diethylaminopropylamine, aminoethylpiperazine, mensendiamine, metaxylylenediamine, dicyandiamide, diaminodiphenylmethane, diaminodiphenylsulfone, methylenedianiline, and metaphenylenediamine. Is raised.

The phenol compound includes biphenol, bisphenol A, bisphenol F and the like, and the phenol resin includes phenol novolak resin, cresol novolak resin, bisphenol A novolak resin and the like. Those having a substituent such as a halogen atom such as bromine or an alkyl group such as a methyl group or a butyl group may be used.

Examples of the acid anhydride include hexahydrophthalic anhydride (HPA) and tetrahydrophthalic anhydride (THP).
A), pyromellitic anhydride (PMDA), chlorendic anhydride (HET), nadic anhydride (NA), methylnadic anhydride (MNA), dodecynylsuccinic anhydride (DDSA), phthalic anhydride (PA), methylhexa Examples include hydrophthalic anhydride (MeHPA) and maleic anhydride. Some of these curing agents may be used in combination.

The epoxy resin composition may optionally contain (d) a curing accelerator. (D) As the curing accelerator, an imidazole compound, an organic phosphorus compound, a tertiary amine, a quaternary ammonium salt, or the like is used, and the use of an imidazole compound in which a secondary amino group is masked with a masking agent is more excellent. A prepreg exhibiting improved storage stability can be obtained. The compounding amount of the curing accelerator is the epoxy resin 1
It is preferably 0.01 to 5% by weight based on 00 parts by weight.

The above imidazole compounds include imidazole, 2-methylimidazole, 2-ethyl-4-
Methylimidazole, 2-phenylimidazole, 2-
Undecylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 4,5-
Diphenylimidazole, 2-methylimidazoline, 2
-Ethyl-4-methylimidazoline, 2-phenylimidazoline, 2-undecylimidazoline, 2-heptadecylimidazoline, 2-isopropylimidazole,
Examples include 2,4-dimethylimidazole, 2-phenyl-4-methylimidazole, 2-methylimidazoline, 2-isopropylimidazoline, 2,4-dimethylimidazoline, and 2-phenyl-4-methylimidazoline.

Examples of the masking agent include acrylonitrile, phenylene diisocyanate, toluene diisocyanate, naphthalene diisocyanate, hexamethylene diisocyanate, methylene bisphenyl isocyanate, melamine acrylate and the like. Some of these curing accelerators may be used in combination.

The epoxy resin composition may further contain a filler, a coloring agent, an antioxidant, a reducing agent, an ultraviolet ray opaque agent, and the like, if necessary.

Each component of the epoxy resin composition is dissolved or dispersed in a solvent to form an epoxy resin varnish, which is impregnated into a glass woven fabric or a glass nonwoven fabric, and dried to form a prepreg. The type of glass woven fabric or glass non-woven fabric used here is not particularly specified, and those having a thickness of 0.02 to 0.4 mm can be used according to the thickness of the target prepreg or laminate. The resin impregnation amount is appropriately determined in consideration of the thickness of the target prepreg or laminated plate, but is preferably 30 to 80% by weight, more preferably 40 to 70% by weight, based on the entire prepreg. Drying conditions when producing prepreg are as follows:
Although the conditions for forming the B-stage are appropriately selected, it is preferable to select a drying temperature of 60 to 200 ° C. and a drying time of 1 to 30 minutes in accordance with the desired prepreg characteristics.

The prepregs obtained according to the desired thickness of the laminated board are laminated, and a metal foil is laminated on one or both sides thereof, and heated and pressed to produce a laminated board. Copper foil, aluminum foil and the like are used as the metal foil. Metal foil thickness is usually 5
２００200 μm.

The heating temperature during the production of the laminate is preferably 1
The temperature is 30 to 200 ° C, more preferably 160 to 180 ° C, the pressure is preferably 0.5 to 10 Mpa, more preferably 1 to 4 Mpa, and the prepreg characteristics, the capacity of the press machine, the thickness of the target laminated board, and the like. Determined by The obtained metal foil-clad laminate is subjected to ordinary circuit processing to form a printed wiring board.

[0023]

Example 1 Bisphenol A type epoxy resin (using Epicoat E5048 (trade name of Yuka Shell Epoxy Co., Ltd.)) 100
Parts by weight, 15 parts by weight of a phenol novolak resin (trade name: Phenolite TD-2131 of Dainippon Ink and Chemicals, Inc.), 0.5 parts by weight of 2-phenylimidazole, and acrylic rubber (weight average molecular weight) as a high molecular weight resin : 1.2 million, trade name HT of Teikoku Chemical Industry Co., Ltd.
R-600) was dissolved in a mixed solvent of methyl ethyl ketone, toluene and ethylene glycol monomethyl ether (weight ratio: 10: 10: 1) to obtain a varnish having a resin solid content of 50% by weight (high molecular weight resin). Is 30% by weight of the total solids). This varnish is 50 μm thick
Impregnated into glass woven fabric (MIL part number 1080 type)
Dry in a dryer at 160 ° C. for 6 minutes, resin content 62% by weight
A prepreg in the B-stage state was obtained. This prepreg did not scatter resin powder from the cut end and the surface during cutting and handling. The obtained four prepregs are stacked, copper foil having a thickness of 18 μm is arranged on both sides thereof, and a pressure of 3M is applied.
The mixture was heated and pressed at a temperature of 175 ° C. for 90 minutes to obtain a double-sided copper-clad laminate. The copper foil peel strength of this double-sided copper-clad laminate was 1.55 kN / m.

Example 2 Bisphenol A novolak type epoxy resin (using Epicron N-865, trade name of Dainippon Ink and Chemicals, Inc.) 25 parts by weight, bisphenol A type epoxy resin (trade name of Yuka Shell Epoxy Co., Ltd. Epicoat) 82
8), 70 parts by weight, 45 parts by weight of bisphenol A novolak resin (using phenolite vh-4170 of Dainippon Ink and Chemicals, Inc.), 33 parts by weight of tetrabromobisphenol A, 0.9 parts by weight of undecyl imidazole And acrylic rubber (Mw: 480,000, trade name HTR of Teikoku Chemical Industry Co., Ltd.)
-790) was dissolved in a mixed solvent of methyl ethyl ketone, toluene and ethylene glycol monomethyl ether (weight ratio: 10: 14: 1) to obtain a varnish having a resin solid content of 52% by weight (high molecular weight resin). The mixing ratio is 20% of the total solids). The varnish was impregnated into a 50 μm glass woven fabric and dried in a dryer at 170 ° C. for 4 minutes to obtain a prepreg in a B-stage state having a resin content of 58% by weight.
This prepreg did not scatter resin powder from the cut end and the surface during cutting and handling. The obtained four prepregs were stacked, copper foil having a thickness of 18 μm was placed on both sides thereof, and heated and pressed at a pressure of 3 Mpa and a temperature of 175 ° C. for 90 minutes to obtain a double-sided copper-clad laminate. The copper foil peel strength of the double-sided copper-clad laminate was 1.45 kN / m.

Comparative Example 1 A resin solid content of 54% was obtained in the same manner as in Example 1 except that the compounding amount of the high molecular weight resin in Example 1 was changed to 12 parts by weight.
% Varnish (9% of total solids). The varnish was impregnated into a glass woven fabric having a thickness of 50 μm, and dried in a dryer at 160 ° C. for 5 minutes.
A prepreg in the B-stage state was obtained. In this prepreg, resin powder scattered from the cut end and the surface during cutting and handling. The obtained four prepregs were stacked, copper foil having a thickness of 18 μm was placed on both sides thereof, and heated and pressed at a pressure of 3 Mpa and a temperature of 175 ° C. for 90 minutes to obtain a double-sided copper-clad laminate. As a result of measuring the copper foil peeling strength of this double-sided copper-clad laminate, it was 1.50 kN / m.

Comparative Example 2 A varnish having a resin solid content of 56% was obtained in the same manner as in Example 1 except that no high molecular weight resin was used. A prepreg having a resin content of 62% was obtained in the same manner as in Example 1 using this varnish. In this prepreg, resin powder scattered from the cut end and the surface during cutting and handling. The obtained four prepregs were stacked, copper foil having a thickness of 18 μm was placed on both sides thereof, and heated and pressed at a pressure of 3 Mpa and a temperature of 175 ° C. for 90 minutes to obtain a double-sided copper-clad laminate. The copper foil peel strength of this double-sided copper-clad laminate was 1.35 kN / m.

Comparative Example 3 A resin solid content of 5 was obtained in the same manner as in Example 2 except that the compounding amount of the high molecular weight resin in Example 2 was changed to 94 parts by weight.
A varnish of 0% by weight was obtained (the blending ratio of the high molecular weight epoxy resin was 35% of the total solids). Using this varnish, a prepreg having a resin content of 58% by weight was obtained in the same manner as in Example 2. This prepreg did not scatter resin powder from the cut end and the surface during cutting and handling. The obtained four prepregs were stacked, copper foil having a thickness of 18 μm was placed on both sides thereof, and heated and pressed at a pressure of 3 Mpa and a temperature of 175 ° C. for 90 minutes to obtain a double-sided copper-clad laminate. The copper foil peel strength of this double-sided copper-clad laminate was 1.51 kN / m.

After etching the copper foil of the double-sided copper foil-clad laminate thus obtained, PCT resistance and substrate solder heat resistance were measured. Table 1 shows the results.

Incidentally, the PCT resistance is as follows: saturated vapor pressure, 120
In a pressure cooker at 2027 hPa and 2027 hPa, Table 1
4 shows the results of visual observation of changes in the appearance after the time treatment described in Example 1. Each symbol represents ○: no change, ×: occurrence of measling or bleeding, and three symbols show the results of evaluation using three test pieces, respectively.

The solder heat resistance of the substrate is 120 ° C., 2
After treatment in a pressure cooker of 027 hPa for 2 hours, D-6 / 100 treatment (boiling for 6 hours), and then C-192 / 40 /
This is a result of observing the base material immersed in a solder bath at 260 ° C. for 20 seconds after performing 90 treatments (standing for 192 hours in a thermo-hygrostat at 40 ° C. and 90% humidity). Each symbol represents ○: no change, Δ: occurrence of measling, ×: occurrence of blistering, and three symbols indicate the results of evaluation using three test pieces, respectively.

[0031]

[Table 1]

[0032]

According to the present invention, it is possible to obtain a prepreg with less scattering of resin powder at the time of cutting or handling, without lowering the laminate properties such as heat resistance. Also, by using this prepreg, a laminate excellent in copper foil peeling strength can be obtained.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Yoshiyuki Takeda 1500 Oji Ogawa, Shimodate-shi, Ibaraki F-term (reference) 4F100 AB01B AB33B AG00A AK25A AK27A AK53A AL01A AL05A BA02 CA02A DH01A EJ82A GB43L JL11 YY00A 4J002 BG042 BG052 CC043 CC053 CC063 CD021 CD051 CD061 CD071 CD111 EJ036 EL136 EL146 EL146 FD133 FD146 FD150 GQ00

Claims (5)

[Claims] (1) (a) a weight average molecular weight of 200,000 to 150
An epoxy resin composition for a printed wiring board, comprising, as essential components, a high molecular weight resin which is a copolymer containing an acrylic ester as an essential component, (b) an epoxy resin and (c) a curing agent. 2. The epoxy resin composition for a printed wiring board according to claim 1, wherein the high molecular weight resin (a) is contained in an amount of 10 to 30% by weight based on the total amount of resin solids. 3. The epoxy resin composition for a printed wiring board according to claim 1, wherein the high molecular weight resin (a) is a copolymer containing butyl acrylate and acrylonitrile as essential components. 4. A prepreg for a printed wiring board, wherein the prepreg for a printed wiring board is formed by impregnating the epoxy resin composition for a wiring board according to any one of claims 1 to 3 into a glass woven fabric or a glass nonwoven fabric to form a B stage. 5. A metal foil-clad laminate obtained by disposing a metal foil on one or both sides of a prepreg for a printed wiring board according to claim 4 or a laminate obtained by laminating two or more of the prepregs and heating and pressing the laminate. .