JPS60260627A - Production of prepreg for printed wiring board - Google Patents

Abstract

PURPOSE:To obtain the titled prepreg, by impregnating a glass cloth or a nonwoven glass fabric with a varnish obtained by mixing a specified epoxy resin with a polycondensation product between bisphenol A and formaldehyde, a cure accelerator, and a solvent and drying the impregnated cloth or fabric. CONSTITUTION:The titled prepreg is obtained by impregnating a glass cloth or a nonwoven glass fabric with a varnish essentially consisting of (a) an epoxy resin comprising 1-100wt% glycidyl ether of a polycondensation product between bisphenol A or F and formaldehyde or a mixture thereof, (b) a polycondensation product between bisphenol A and formaldehyde in an amount of, preferably, 1-100pts.wt., per 100pts.wt. component (a), (c) a cure accelerator (e.g., imidazole compound) in an amount of, preferably, 0.01-5pts.wt. per 100 pts.wt. component (a), and (d) a solvent (e.g., acetone), and drying the impregnated cloth or fabric at 80-200 deg.C.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to epoxy glass cloth, which is a material for printed wiring boards;
The present invention relates to a method for producing an epoxy-glass nonwoven fabric fabric leg.

[Prior art]

Print layout +11ii! BACKGROUND ART As the density of boards increases, the diameter of through-holes becomes smaller, and prepregs for printed wiring boards with excellent drillability and metal-clad laminates obtained using prepregs are required. In terms of drilling workability, the occurrence of smear significantly impairs the through-hole conductivity by preventing conduction between the inner layer circuit steel and the through-hole plated steel. In order to remove smear, printed circuit board manufacturers either perform a smear removal process or use concentrated sulfuric acid, hydrofluoric acid, and other sound sources, which poses safety issues and also causes damage to the inner wall of the through hole and reduces reliability. The cause of this is that the resin softened by the frictional heat generated by the drill or the drill adheres to the cross section of the inner layer circuit copper.

Dicyandiamide, which has been conventionally used as a curing agent for epoxy glass fabric prepregs, has poor compatibility with resins and often remains unreacted.

For this reason, cured resin products soften as the resin decomposes when the temperature exceeds 250°C.In order to prevent such softening of the cured product, a curing agent that is compatible with the epoxy resin and has good reactivity is required. be done. The 1st epoxy position and 1st fat are also required to be heat resistant and have good reactivity.

[Purpose of the invention]

The present invention is intended for use in printed wiring boards with the aim of improving drill workability, which is a disadvantage of conventional epoxy resin-cycyandiamide yarns, and improving heat discoloration and storage stability, which are disadvantages of epoxy tung fat-borifphenol yarns. The present invention relates to a method for producing an epoxy-glass cloth prepreg and an epoxy-glass nonwoven prepreg.

[Structure of the invention]

The present invention is based on (a) a glycidyl etherified product of a polycondensed metal with bisphenol A or bisphenol F formaldehyde, or a mixture thereof at an epoxy position containing 1 to 100% by weight (b) a disarmament metal of bisphenol A and formaldehyde ( This is a method for producing a prepreg for a printed wiring board, which comprises impregnating a glass nonwoven cloth covered with a purple glass cloth with a varnish containing c) hardening accelerator and (d) a solvent as all essential components, and then drying the impregnated varnish.

The present invention will be explained in detail below.

The epoxy resin (a) contains, as an essential component, a glycidyl etherate of a polycondensed metal of bisphenol A-f or bisphenol F and formaldehyde, or a mixture thereof in an amount of 1 to 10% by volume. The molecular violet of ゛ 1 (・There is no limit.

There are no restrictions on the type of epoxy resin used as a component other than the above, and the epoxy resin of the present invention has a faster curing speed and higher crosslinking density than phenol novolac type epoxy resin or cresol novolac type epoxy resin alone. Therefore, drill workability is good.

This is thought to be because the epoxy resin (a) or the epoxy resin (b) has good compatibility because it contains an epoxy resin having the same skeleton as the polycondensate.

Examples of other epoxy resins that can be incorporated into the epoxy resin of the present invention include bisphenol A type epoxy resin, bisphenol Fm epoxy resin, bisphenol S type epoxy resin, phenol noholac type epoxy resin, cresol/Ho7 ivy type epoxy resin, and resin. There are cyclic epoxy resins, glycidyl ester type epoxy resins, glycidylamine type epoxy resins, hydantoin type epoxy resins, incyanurate type epoxy resins, and their halogenated and hydrogenated 7JD products, and several types are used in combination. You can also do that. Furthermore, there are no restrictions on the method of mixing these epoxy resins or their hardness.

When flame retardancy is required for the manufactured prepreg, a halogenated epoxy resin may be used in addition to the glycidyl ether of a disarmament metal of bisphenol A or bisphenol F and formaldehyde, which are essential components, or a mixture thereof. Become.

In addition, it is necessary to make the manufactured prepreg flame retardant, and the essential components of the epoxy resin (a) are glycidyl ethers of disarmament metals such as bisphenol At, bisphenol F, and formaldehyde, or mixtures thereof r epoxy resin 100 weight In order to contain more than 8 parts by weight of fat, halogenated epoxy resin alone cannot provide sufficient flame retardancy, and tetrabromobisphenol A1 decabromodiphenyl ether, antimony trioxide, tetraphenylphosine 74: 1. It is preferable to include a compound called a flame retardant. In order to maintain the properties of prepreg for printed wiring boards, the amount of flame retardants other than halogenated epoxy resin should be kept to the minimum necessary, and at most 100M parts of epoxy resin. It is desirable that the amount is 60 parts by weight or less.

Further, when a common phenol resin is used as a curing agent for an epoxy resin, there is a problem of discoloration upon heating of the cured product, but in the present invention, there is no problem because (b) a polycondensate of bisphenol A and formaldehyde is used.

There is no restriction on the molecular weight of the polycondensed metal of bisphenol A and formaldehyde (b), and the bisphenol A monomer may be the same.

The amount to be blended is not limited, but is 1 to 100 parts by weight per 100 parts by weight of the epoxy resin.

Further, all of the 7 enol novolak resins may be used in combination within a range that does not impair the effects of the present invention.

As the curing accelerator (c), imidazole compounds, organic phosphorus compounds, tertiary amines, quaternary ammonium salts, etc. are used, but secondary amino group-coated acrylonitrile,
By using an imidazole compound masked with incyanate, melamine, acrylate, etc., it is possible to obtain a prepreg with storage stability more than twice that of conventional prepreg. The imidazole compounds used in this are imidazole, 2-
Ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 1-benzyl-2-methylimidazole, 2
-Heptadecylimidazole, 4,5-diphenylimidazole, 2-methylimidacillin, 2-ether-4-
Methylimidacilline, 27enylimidazoline, 2-undecylimidazoline, 2-heptadecyl imidazoline, 2-isopropylimidazole, 2,4-dimethylimidazole, 2-phenyl-4-methylimidazole,
2-ethylimidazoline, 2-inpropylimidai
IJ:y, 2.4--)jfyb4 i fi“l
'l) 7.2-7, , a: 1-2-4-methylimidacillin, etc. (Masking agents include acrylonitrile, 7-ethylene diincyanate, toluene diincyanate, naphthalene diincyanate, and heyasa. Examples include methylene diisocyanate, methylene bisphenyl isocyanate, and melamine acrylate.

These curing accelerators may be used in combination with persimmons or grapes, and l: is preferably epoxy (0.01 to 5 parts by weight based on 100 parts of fat). If the amount is less than 0.011 parts, the effect will be small, and if it is more than 5 M parts, there will be no storage stability.

The solvent for (d) is acetone, methyl ethyl ketone,
Toluene, xylene, methyl in phthyl ketone, ethyl acetate, ethylene glycol monomethyl ether, N, N
-Dimethylformamide, N,N-dimethylacetamide, methanol, ethanol, etc., and some of these may be used in combination.

Also, (a) s (b), (c), id) above are essential components, and it is possible to mix them with any other compound sound. After mixing and applying the varnish to the glass cloth or glass non-woven cloth,
It is dried in a drying oven 9 at a temperature of 80 to 200°C to obtain a prepreg for printed wiring boards. Is prepreg heated and pressed to produce printed wiring boards or metal clad laminations? Used for manufacturing.

All examples of the present invention will be described below.

Example 1 Bisphenol A 1,000g, 57% formalin 22
0 g, oxalic acid 10 g? The mixture was placed in a four-loop flask equipped with an r-cooling tube and a stirrer, refluxed for 2 hours to react, and then dehydrated and concentrated to obtain bisphenol A novolac resin [A) W. This purple varnish was prepared using the following formulation.

Epicron N-865 (bisphenol novolac type epoxy resin) 100 parts by weight (Product name: Dainippon Ink @
) Bisphenol A novolac resin [A] 60 weight tS 2E4MZ-CN (1-cyanoethyl-2ethyl-4-
Methylimidazole) 0.5 parts by weight 10- (Product name: Nishikoku Kasei ■) Methyl ethyl ketone 100 parts by weight A glass cloth with a thickness of 0.1 mm+ was impregnated with this varnish, and dried at 130°C for 5 minutes to obtain a prepreg. Ta.

Example 2 Bisphenol A novolac resin [A
) 8011 (brominated bisphenol A epoxy resin) 80 parts by weight (product name: manufactured by Ciba Kaigy Co., Ltd.) Ebicuron N-86520 parts by weight Bisphenol A novolac Resin [A] 3ON parts LX-1006 (Incyanate mask imidazole) (Part name: Dai-Kogyo Co., Ltd.) 0.5 parts by weight Acetone
90 parts by weight of this varnish was impregnated into a 1 mm thick glass cloth.
The prepreg was dried at 10°C for 5 minutes.

Example 6 Bisphenol A novolac resin CA in Example 1
) A varnish was obtained by blending as follows using x.

Ebicuron N-880 (Bisphenol A novolac type Evo dried resin) 50 parts by weight (Product name Ni-Dainichifu Insen-
(manufactured by) ESB-400 (brominated bisphenol A type Evochishi resin) 50 weight is (product name: manufactured by Sumitomo Kaji ■) Bisphenol A novolac I (lff1 (A) 40
Sadashigebe C1l Z AZINE (2,4-diamino-6(2'
1 part (Product name: manufactured by Nishikoku Kasei) Methyl ether ketone 90 parts ・1 part (Product name: Nishikoku Kasei) impregnate the cloth
Example 4 The bisphenol A novolac resin (A
)' was used to obtain a varnish mixture as follows.

Araldite 8011 80 parts by weight Epicron N-88020 parts by weight Bisphenol A novolak 1lt (A) 10Jti parts H-1 (phenol novolac resin) 20 parts by weight (product name: manufactured by Meiwa Kasei ■) 2PZ-CN (1-cyanony Y- h-2-phenylimidazole) 0.5 parts by weight (Product name: Shikoku Kasei Co., Ltd.) Acetone 90 parts by weight This varnish was impregnated into a glass cloth of tO11 and heated to 110°C.
The prepreg was dried for 5 minutes to obtain a prepreg.

Comparative Example 1 Araldite 8011 80 double parts EOCN102 (Taresol novolac type epoxy resin 20 parts by weight 15- (trade name manufactured by Nippon Kayaku) Dicyandiamide 4 parts by weight BDMA (benzyldimethylamine) 0.5 parts by weight Methyl ethyl ketone 5 oii parts A glass cloth having a thickness of 1 mm was impregnated with 40 parts by weight of ethylene glycol monomethyl ether and dried at 160° C. for 5 minutes to obtain a prepreg.

Comparative Example 2 In Example 1, EOCN102. A prepreg was coated in the same manner as in Example 1 using S'+0(] weight.

Comparative Example 3 In Example 2, 0.3 parts by weight of 2E4MZ (2-ethyl-4-methylimidazole trade name: Shikoku Kasei ■) was used instead of 0.5 parts by weight of LX-1006.
Prepreg was obtained in the same manner as above.

14- Comparative Example 4 Bisphenol A novolak lf in run flJ2
A prepreg tray was obtained in the same manner as in Example 2 except that 50 parts by weight of fat (A) was replaced by phenol novolak resin H-1,303i Dobe.

Table 1 shows the varnish formulations and drying conditions of Examples and Comparative Examples.

Table 1 Varnish formulation and drying conditions Gripreg 15 obtained in Examples 1 to 4 and Comparative Examples 1 to 4 above
A 6-layer printed wiring board was produced by heat forming at 170℃ for 60 minutes using 36 sheets of 35μ wire and 36 sheets of 35μ wire W, and drilling was performed. .

Hole diameter 1.0φohm, number of stacked 2 sheets is 12,000 bi
I drilled holes up to ts.

The results of the drill workability test and other characteristic tests of the 6-layer printed wiring board are shown in Table 2 above.

17- Note 1) Smear occupancy rate of the copper cross section of the inner layer of the through-hole using 20 nitrile combs, rotation speed 60.00 Orpm, 1 layer, 2 sheets Note 2) Drilling conditions Note 1) 20 holes with the maximum roughness of the inner wall of the through-hole as per vclmj 3) Extraction with DMF 100°C, 10 hours Note 4) Using a viscoelastic spectrometer Average feed rate of 2,400 Dim/min Bisphenol A novolac as shown in Table 2 It can be seen that when resin (A) is not used, the smear occurrence rate is non-electrically small.

Of course, when comparing Example 1 using bisphenol A novolac type epoxy resin 7 and Comparative Example 2 using cresol novolac type epoxy resin, the force in Example 1 is lower due to the extraction rate by DMF and 1g is higher. When comparing Example 2 and Comparative Example 4r, there is a significant difference in heat discoloration, indicating that bisphenol A novolak resin (A) has good heat discoloration.

When Example 2 and the three comparative examples are compared, there is a remarkable difference in storage stability, and the effect of masked imidazole on storage stability is clear.

〔Effect of the invention〕

As described above, it can be seen that the printed wiring pattern J prepreg of the present invention has much better drilling workability for multilayer wiring boards and storage stability of the prepreg than the prior art.

Claims (1)

[Scope of Claims] 1. (a) Ebosenshimi fat containing 1 to 100% by weight of a glycidyl ether of a polycondensed metal of bisphenol A or bisphenol F and formaldehyde, or a mixture thereof (b) Bisphenol A and formaldehyde A method for producing a prepreg for a printed wiring board, which comprises impregnating a polycondensed metal material (c) a curing accelerator and (d) a solvent into a varnish cloth or a glass nonwoven fabric, which is blended as all essential components, and then drying it. 2. The method for producing a prepreg for printed wiring according to claim 1, wherein the curing accelerator is an imidazole compound in which a secondary amine group is masked.