JPS62161820A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:The titled composition that contains an epoxy resin, a polyfunctional phenolic resin, a triazole or indazole derivative and a curing accelerator, thus showing high adhesion to metal and good drilling processability, when it is used as a material for printed circuit boards. CONSTITUTION:The objective composition contains, as essential components (A) an epoxy resin such as bisphenol A type epoxy resin, (B) a polyfunctional resin, such as bisphenol A novolac resin, (C) a triazole such as a compound of formulas I-IV (R1-R12 are H, methyl, phenyl, hydroxyl, amino) or an indazole and (D) a curing accelerator, preferably an imidazole bearing a masked imino group. The amount of component B corresponds to 0.5-1.5 equivalent of phenolic hydroxyls based on the epoxy groups, component C is 0.1-10pts.wt. per 100pts.wt. of resin A and component D is 0.01-5pts.wt. per 100pts.wt. of resin A.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an epoxy compound that has excellent contact properties with metals.

[Conventional technology]

As printed wiring boards have become more expensive, the number of holes has increased and through holes have become smaller in diameter, and materials for printed wiring boards with good drillability are now available.

In terms of drilling workability, the occurrence of smear significantly impairs through-hole reliability by interfering with the four connections between the inner layer circuit steel and the through-hole plating steel. In order to remove smear, printed plate manufacturers use a smear removal process, but it poses a safety problem because it contains concentrated sulfuric acid, hydrofluoric acid, chromic acid, and other ingredients. In addition, such treatment roughens the inner wall of the through hole and becomes an original mark that reduces the reliability of the through hole. The cause of smear is that the resin softened by the heat generated during drilling is attached to the cross section of the inner layer circuit copper foil inside the through hole. Even when the conventional prepreg for the paulownia distribution plate used for convenience is sufficiently cured, the temperature at which it softens and fuses is low, at about 250°C.

Generally, the temperature of the drill during drilling is said to be around 500℃, which is equivalent to Takumi's prepreg for printed rolling boards (
Hardened fat (e.g. Dicyancia ε hardened epoxy fallen fat)
Then, it softens and adheres to the cross section of the steel foil, forming a smear.

In addition, if printed wiring boards are used with parts mounted on them, 1
Temperatures may exceed 00°C.

Therefore, long-term heat resistance in air is required.

It was manufactured using prepreg for printed wiring boards, which has been used conventionally. When the laminate is treated for a long time in a drying oven at t-170°C, it takes about 500 hours until the bending strength retention rate becomes 50% or less. By lengthening this time, the parts can be energized and used in multiples.
Improves reliability when

An epoxy resin cured with a polyfunctional phenol resin is a finely structured system that satisfies the above requirements. When applied to a polyfunctional phenol-cured epoxy-based prepreg for printed wiring boards, the occurrence of smear during drill workability is more than half that of conventional products using dicyandiamide-cured epoxy cutting B, and long-term heat resistance. The processing time at 170°C until the odor-C1 bending strength retention rate becomes 50% or less is more than twice that of conventional products.

However, epoxy resins using polyfunctional phenol resins as curing agents do not have better contact with metals such as foils than conventional products. For example, the peeling strength of a 55 μm thick copper foil with fA on one side is approximately 2 kg / c with conventional products.
rn, whereas in products using polyfunctional phenol-cured epoxy resin, it is about 1 to 1.5 kg/cm.

Furthermore, when the shiny surface of gold #4 is subjected to roughening and oxidation treatment, the peel strength also decreases. For example, the adhesion of the conventional product to the glossy surface of copper foil treated in this way is FJl, 5k.
g/Ca, whereas for products using polyfunctional phenol-cured epoxy resins, it is approximately [15 to 1 kg/Ca].
cm. Furthermore, when measuring the peel strength after immersing these test pieces in hydrochloric acid, the peel strength of conventional products hardly decreases, but the value varies with products using polyfunctional phenol-cured epoxy resin.

[Problem that the invention seeks to solve]

The present invention is a multifunctional phenol-cured epoxy resin that meets the above-mentioned circumstances and provides excellent drill workability and long-term atmospheric heat resistance when applied to materials for printed wiring boards. The purpose of this is to improve layering properties with metals.

[Means for resolving all points of merit]

That is, the epoxy side-type composition of the present invention is characterized in that (a) epoxy phenol (bl) polyfunctional phenol (c) triazole compound or V eindazole enzyme conductor, and +dl curing accelerator as all essential components. .

Hereinafter, one aspect of the present invention will be explained in detail.

As for the epoxy type side of fa), any polyfunctional n and r may be used, for example, bisphenol A21"
J epoxy resin, bisphenol 1M epoxy resin,
Bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy 4E resin,
Bisphenol F novolac type epoxy 4I! 1 fat, phase-embedded epoxy resin, glycidyl ester type epoxy bright resin, glycidylamine type epoxy side resin, hydantoin type epoxy resin, incyanurate type epoxy resin 14, aliphatic chain type epoxy type side and so on, etc. There are halides, water additives, etc., and any molecular weight may be used, and several types may be used in combination.

The polyfunctional phenol type side of (b) may be any of the following: bisphenol A, bisphenol F1, polyvinylphenol, Alternatively, there are novolac fats such as phenol, cresol, alkylphenol, catechol, bisphenol A, and bisphenol F, and halogenated phenol resins such as these. It is also possible to use several types of these phenol compounds together. From the viewpoint of drill workability, it is preferable for the blending gt to be in a range of 0.5 to 1.5 equivalents of phenol hydroxide group to epoxy group.

Tel's triazole compounds are produced by Houzou, which costs 500 million yen under GD.

RI 5R12 in this formula is a tributary group, hydrogen,
There are methyl groups, 2-enyl groups, hydroxyl groups, amino groups, mercapto groups, halogens, carboxyl groups, etc.

In addition, the indazole conductor has the following structure.

Serving groups R, %R, etc. include hydrogen, alkyl groups, phenyl groups, halogens, hydroxyl groups, nitro groups, amino groups, benzoyl groups, acetyl layers, carboxyl groups, and mercapto groups.

Several kinds of these compounds can be used in combination.

Formulated with epoxy a (fat 100 m (0 for mold part)
．． Preferably, it is 1 to 10 parts of sodium bicarbonate.

If the amount is less than 0.1 weight and 1 part, the adhesion strength such as the strength for cutting senpai will not be sufficient, and if it is more than 107%, the heat resistance such as drill workability will decrease.

(d) as a curing accelerator, Q-tech, imidazole compound,
Organic phosphorus compounds, tertiary amines, quaternary ammonium salts, etc. are used, but when imino and imidazole compounds are masked with acrylonitrile, incyanate, melamine acrylate, etc., conventional 2 It is possible to obtain a prepreg that has more than double the storage stability.

The imidazole compounds used here include imidazole, 2-ethylimidazole, 2-ethyl-4-
Methylimidazole, 2-7enylimidazole, 2-
undecyl imidazole, 1-benzyl-2-ethylimidazole, 2-heptadecyl imidazole-4e
5yphenylimidazole, 2-methylimidacillin.

2-7enylimidazoline, 2-undecylimidacilline, 2-heptadecyl imidacilline, 2-isopropylimidazole, 2,4-dimethylimitasole, 2-phenyl-4-methylimidazole, 2-ethylimidazole Dacilin, 2-isopropylimidacyline, 2,4-dimethylimidacyline, 2-7enyl-4-methylimidacyline, etc., and masking agents include acrylonitrile, phenylene diisocyanate, toluene diisocyanate, Examples include naphthalene diisocyanate, hexamethylene diisocyanate, methylene bisphenyl isocyanate, and melamine acrylate.

These curing accelerators can be used in combination with the same or all of them. For 10 C11ffd, 0.111 to 5 weight far is preferable OO,01
[If the amount is less than -rfr, the promoting effect will be small, and if it is more than 5M, the storage stability will be poor.

Although the epoxy side-type composition according to the invention is available in the form of a droplet, a bath agent is often required when applying it to a substrate. As bath agents, acetone, methyl ethyl ketone, toluene, xylene, methyl imbutyl ketone, ethyl acetate, ethylene glycol monomethyl ether, N, N-dimethylformide.
%.

Examples include N-dimethylacetamide, methanol, and ethanol, and several types of these may be used in combination.

The above ta), (bl, (cl, (dl) are distributed and the base materials such as samurai varnished glass cloth, crow cloth or kite, cloth with components other than glass are used carefully, and the drying oven is heated to 80%. ~2
By drying in the range of 00°C, a prepreg for a printed wiring board is obtained. The prepreg is heated and pressed to produce a printing board 15-gold laminate (hereinafter referred to as cL).
It is used for various purposes.

Drying here refers to removing the solvent when drilling is used, and making the material lose its fluidity at room temperature when no solvent is used.

〔Example〕

Below, VIL1@ example of the present invention will be described.

Example 1 Brominated bisphenol A type epoxy resin (1 epoxy resin)
1530) 80 heavy mold part phenol novolac type epoxy resin (Epoxy 11200) 20. tit part phenol novolac resin 501f amount part 1.2,4-
0.53 ifi part of 2-ethyl-4-methylimidazole whose imino group was masked with quinamethylene diinocyanate to 2MMN The above compound was dissolved in methyl ethyl ketone to prepare a varnish with a non-volatile content of 60%.

Example 2 In place of 1,2,4-triazole in Example 1, 2 parts by weight of benzotriazole was blended.

Example 5 In place of 1,2,4-triazole in Example 1, 2 parts by weight of 5-amino-1,2,4) riazole was used.

Example 4 In place of the strength of 1,2,4-triazole in Example 1, 2 parts by weight of 1-hydroxybenzotriazole was blended.

Next, a comparative example will be shown to confirm the effects of these examples.

Comparative Example 1 In implementation fp01? , 2.4-) Riazole was not blended.

Comparison? I12 2-ethyl-4-methylimidazole ec instead of 2-ethyl-4-methylimidazole in which all imino groups were masked with hequinamethylene diisocyanate in Example 1.
Contains a single neck.

Comparative Example 3 In place of the phenol novolak resin in Example 1, 4 parts by weight of dicyandiamide were combined. Additionally, ethylene glycol monomethyl ether was added as a solvent.

Varnish tα1mro obtained in Examples 1 to 5 and Comparative Examples 1 to 5
After impregnating a thick glass cloth, the mixture was heated at 140° C. for 5 minutes to obtain a prepreg. 3 pieces of prepreg obtained in this way and 3
Using two sheets of 5 μm thick copper foil, heat at 170°C for 60 minutes for 50 minutes.
A 411 layered board was produced under the condition of kg/an'. Using this MCLK inner layer circuit-processed box, five MCL sheets, and six prepreg sheets, a No. 6 wiring board was fabricated. This six-layer wiring board was used to evaluate drilling resistance, air heat resistance, copper foil peeling strength, and soldering heat resistance. In addition, in order to improve the coexistence stability of prepreg, we changed the course of prepreg gel time #f:f realization. The results are shown in Table 1.

Note 1) Method for evaluating smear incidence: Through-hole plating was applied to a drilled 6-7fl wiring board, and the cut surface of the through-hole was measured using a microscope at 50°C.
00 hits, 2 around 10000 hits
The connection part between the #fI copper and the through-hole plated steel was observed and the smear occurrence rate was completely evaluated.

Smear occurrence rate; WIJ table'5 of the height of the smear occurring relative to the connection height for each connection. : Increased and averaged.

Note 2) Outside the outer layer peeling strength measurement method! 1 Form a line with a width of 1 m on the copper foil and peel off the line in the 90° force direction'ff, 5QffII
The peeling speed of Il/Ran was measured.

Inner layer steel foil peeling strength measurement method V3m @ Roughening treatment and refining steel treatment on the glossy surface of the foil f! The peel strength between the copper oxide treated surface and the prepreg resin was measured under the same conditions.

Silicic acid treatment method 1 The MCL prepared by forming a line with a beating width was immersed in 18% hydrochloric acid at 65° C. for 60 minutes.

Note 3) Soldering heat resistance: Dip in solder at 260°C for 20 seconds and visually evaluate the appearance. If there is no swelling, it is OK.

The one with F〈n was designated as tNG.

Note 4) Heated at 170° C. for a long time in an MCL-i dryer with air heat resistance etching. Bending strength fr: Measured every 100 hours, and the number of treatment hours when the bending strength before treatment became 1/2 or less of the Hanaibutton was shown in the table.

Note 5) Prepreg Gel Time The initial value is the gel time at 160°C of the prepreg immediately after coating, and the gel time at 160'C of the prepreg after storage for 60 days at a temperature of 20°C and a humidity of 40% t lll
It was fixed at 11.

As shown in Comparative Example 1, if no triazole compound is used, the steel foil tensile strength will be a low value.

As shown in Comparative Example 2, when mask imidazole is not used, the gel time of the prepreg changes significantly over time, resulting in poor storage stability. When the curing agent was changed to dicyandiamide as in Comparative Example 5, the smear occurrence rate increased and drilling performance deteriorated.

Example 6 Brominated bisphenol A type epoxy side type (epoxy equivalent: 550) 80 heavy Its phenol novolac type epoxy side type epoxy side type 200) 20 heavy Its phenol novolak & (fat 5ON111H indazole)
2-Ethyl-4-methylimidazole with all imino groups masked with 2 parts by weight of hexamethylene diisocyanate cL5″M Dogun Above compound L@
A varnish with a non-volatile content of 60% was prepared by dissolving the mixture in ethyl ketone.

Example 7 In place of indazole in Example 1, a sub-unit of 6-aminoindazole t-2 was blended.

Example 18 Instead of indazole in Example 1, 2 parts by weight of 6-hydroxyindazole-4-camboxylic acid was blended.

Comparative Example 4 2-ethyl-4-methylimidazole'k was used instead of 2-ethyl-4-methylimidazole whose imino group was masked with hexamethylene diisocyanate in Example 1.
Q. 3M Sobe arranged.

Comparative Example 5 In place of the phenol novolak perilla in Example 1, dicyandiamide vil-4 was blended. Further, the solvent was removed and ethylene glycol monomethyl ether was further added.

The varnishes obtained in Examples 6 to 8 and Comparative Example 4S-5 were used in Example 1.
An MCL plate was prepared in the same manner as ``-5'', and a % injection test was conducted.

〔Effect of the invention〕

As is clear from the above description, the epoxy resin composition of the present invention has better properties when applied to materials for ink paulownia wiring boards, drilling workability, ease of peeling off steel, and resistance to heat in air, compared to the conventional technology. It has outstanding PX resistance properties such as % contact, and also has excellent storage stability of the bath liquid, and its industrial value is 11.
1 is large.

Agent: Patent attorney Hiro Shono.

Claims (1)

[Claims] 1. (a) epoxy resin (b) polyfunctional phenol resin (c) triazole compound or indazole derivative,
and (d) an epoxy resin composition containing a curing accelerator as an essential component. 2. The epoxy resin composition according to claim 1, wherein the curing accelerator is an imidazole compound with masked imino groups.