JPH0198668A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition which can give a cracking-resistant protective film useful for protecting electrodes, circuits, etc. formed on the surfaces of wiring boards, electronic components, etc., by adding a specified amount of an inorganic powder treated with a corrosion inhibitor to a resin composition. CONSTITUTION:A thermoplastic resin (A) such as an epoxy, polyimide, silicone, unsaturated polyester or phenolic resin is mixed with ordinary additives (B) such as a curing agent, a cure accelerator and a flexibilizer and 5-60wt.%, based on the total composition, corrosion inhibitor-treated inorganic powder (C) obtained by immersing a high-conductivity inorganic powder (a) comprising BN, AlN, Al2O3, MgO, diamond or the like, of a particle diameter of 0.1-20mu in a solution of a corrosion inhibitor (b) such as benzotriazole, benzimidazole, thiourea or triazine.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an electrode 9 formed on the surface of a wiring board, electronic component, etc.
This invention relates to a resin composition for protecting circuits and the like.

(Prior Art) Conventionally, nine electrode circuits and the like have been formed on the surfaces of wiring boards, electronic components, etc. using metals such as copper and silver because of their good electrical conductivity.

The surface of each of these electrode circuits is usually exposed. Therefore, the electrode is more sensitive to water than K.

This has the disadvantage that circuits etc. are corroded.

In order to eliminate the above-mentioned drawbacks, a protective film is generally formed using a resin composition.

These resin compositions include metal surface technology vol.
．． Nap, pp. 396-401 (1973).

Corrosion prevention technology vol! 27.1la12. 661-670
(1978), Corrosion NAC (
corrosion-NACE) vo/38. Ma
1, pp. 60-62 (1982), Corrosion-NACE
vol! 32. k8゜pages 339-341 (1976)
Resin compositions containing corrosion inhibitors such as nitrogen-containing and sulfur-containing compounds such as benzotriazole and benzothiazole are known.

(Problems to be Solved by the Invention) If the resin composition shown above is used, corrosion, electrolytic corrosion, etc. of the nine electrode circuits etc. can be improved. However, when the corrosion inhibitor is hydrophilic, it is difficult to uniformly disperse the corrosion inhibitor in the resin composition. Furthermore, the thermal conductivity of these resin compositions is 1710 to 1/1,000 lower than that of metals, aluminum oxide, aluminum nitride, boron nitride, etc.
1~0.3 W/m-K (0,09~0.2'IKc
al/hm-°C), and the coefficient of linear expansion is 2 to 3 times higher than that of metals, on the order of 5 to 10XIO-17"e.

As described above, conventional resin compositions have low thermal conductivity and large i-expansion coefficients, so when covering two electrode circuits, etc., there are drawbacks such as cracks occurring in the coated resin composition in a thermal shock test. There is.

The object of the present invention is to provide a resin composition that does not have the above-mentioned drawbacks.

(Means for Solving the Problems) The present invention includes 5 to 50% of inorganic powder treated with a corrosion inhibitor in the entire composition.
The present invention relates to a resin composition containing 60'M amount.

In the present invention, the corrosion inhibitor is not particularly limited, but includes benzotriazole, naphtholtriazole, tolutriazole, 2-mercaptoxazolethiol,
Methylbenzothiazole.

Mercaptothiazoline, dithiocarbamic acid, thiourea, thioacetamide, thiosemicarbazide.

Thiophenol, p-thiocresol, thiobenzoic acid, toluidine, indazole, indole, 2-picoline, 26-lutidine, m-anisidine, p-phenetidine, nitrophenylhydrazine, nitrosophenol, λ4-dinitrophenylhydrazine, triazine, diamino Triazine, trihydroactriazine, 3-amino-1°2.4-)riazine, 6-aza-2-thiothymine, etc. are used.

The inorganic powder is not particularly limited, but it is preferable to use a powder with high thermal conductivity.9 For example, diamond powder, BN
It is preferable to use powder, A/N powder, A/*Os powder, MgO powder, etc., with a particle size of about 0.1 to 20 μm.

There are no particular restrictions on the resin, but examples include thermosetting resins such as epoxy resins, polyimide resins, silicone resins, unsaturated polyester resins, and phenolic resins, together with their curing agents, curing accelerators, flexibility agents, etc. used,
In addition to the above, thermoplastic resin compositions such as saturated polyester resin compositions may also be used.

For information on how to treat inorganic powders with corrosion inhibitors.

Although there are no particular limitations, K can be obtained, for example, by immersing inorganic powder in a corrosion inhibitor solution.

It is necessary that the inorganic powder treated with a corrosion inhibitor be contained in the total composition in an amount of 5 to 60% by weight, and if it is less than 5% by weight, the effect of improving corrosion of the electrode circuit, etc., electrolytic corrosion, etc. will be small; Moreover, if the adhesive strength exceeds 60 volts, the adhesive strength of the resin composition becomes weak.

(Example) The present invention will be explained in detail below.

Example 1 AI whose main component is fine powder with a particle size of 1 μm or less! N powder (Tokuyama Soda Co., Ltd., F grade) was immersed in 44-dinitrophenylhydrazine (Wako Tsumugi Pharmaceutical Co., Ltd., reagent) No. 5 multi-aqueous solution,
It was then dried to obtain corrosion-inhibited A/N powder.

Next, 100 parts by weight of the epoxy resin composition was treated with corrosion prevention treatment AI! A resin composition was prepared by adding 20 parts by weight of N powder to 0 parts by weight.

The epoxy resin composition was prepared using methyltetrahydrophthalic anhydride (manufactured by Hitachi Chemical Co., Ltd., trade name HN-2200) as an acid anhydride curing agent. Dissolution.

The mixture and hydrogenated bisphenol A type epoxy resin (manufactured by Asahi Denka, trade name BP-4080, epoxy equivalent: 23
5-255. Average epoxy weight per [245) 301,
Bisphenol A type epoxy resin (Shell Chemical Exhibition, trade name Epicor) 834. Epoxy equivalent: 225-280.
A uniform mixture of 70 parts by weight (average epoxy equivalent: 250) was used.

On the other hand, one dimension is marked 5oxso, the thickness is IM, and the thickness is 3 on one side.
1 on the steel foil side of a glass nonwoven composite laminate (manufactured by Shin-Kobe Denki, product name E-668) covered with 5 μm copper foil.
Etching treatment was performed using a commonly known method, and the distance between opposing electrodes was 0.2 mm.

A kusiya electrode was prepared having an electrode length of 30 a+m and an electrode width of 0.5 cm and consisting of 20 pairs of electrodes. After that, the resin composition obtained above was printed on the comb-shaped electrode to a thickness of 30 μm by a screen printing method.

It was cured at 140° C. for 40 minutes to form a protective film.

Next, a bias voltage of K100V was applied to the comb-shaped electrode on which the protective film was formed, and the sample was left in an atmosphere of 65° C. and 90° relative humidity (RH) for 100 hours. The initial insulation resistance is 4
The resistance was 10"Ω, and after 100 hours, it decreased to 2X10"Ω, but there was almost no significant difference. Even when the interdigitated electrodes were corroded and the space between the interdigitated electrodes was observed with a microscope at 40x magnification, copper dendrites due to electrolytic corrosion were observed. was not seen.

Further, 100 cycles of a liquid phase thermal shock test (in Fluorinert) from 150°C for 5 minutes to -65°C for 5 minutes were conducted, but no cracks were observed in the protective film.

Comparative Example 1 100 parts by weight of the same epoxy resin composition as in Example 1 was treated with ArN as in Example 1 without corrosion inhibitor treatment.
A resin composition was prepared by adding 20 mL of the powder. Thereafter, a protective film was formed on the comb-shaped electrode in the same manner as in Example 1.

Next, as in Example 1, a bias voltage of 100 V was applied to the interdigitated electrodes, and K100 was applied in an atmosphere of 65° C. and 90 SRH.
I left it for a while. The initial insulation resistance was 5 x 10'', but it decreased to K 5 x 10' after 100 hours, and corrosion was observed in a part of the comb-shaped electrode.

When the space between the comb-shaped electrodes was observed using a microscope with a magnification of 40 times, steel dendrites due to electrolytic corrosion were observed.

Furthermore, when a liquid phase thermal shock test (in Fluorinert) was conducted for 100 cycles from 150° C. for 5 minutes to −65° C. for 5 minutes, many cracks occurred in the protective film on the wiring shoulders.

Example 2 Alumina powder with an average particle size of 1.1 μm (alumina purity 99
．． 54 or more) was immersed in an lOS acetone solution of mercaptobenzothiazole (manufactured by Wako Pure Chemical Industries, Ltd., reagent) and then dried to obtain corrosion inhibitor-treated alumina powder 1. In addition, the same alumina powder as above was added to Indazole (manufactured by Wako Pure Chemical Industries, Ltd., reagent) 5
The powder was immersed in an aqueous solution (70°C) of K, and then dried to obtain corrosion inhibitor-treated alumina powder 2.

Next, 40 parts by weight of corrosion-inhibited alumina powder 1 and 40 parts by weight of corrosion-inhibited alumina powder 2 were added to 100 parts by weight of the epoxy resin composition to obtain a resin composition.

The epoxy resin composition has an average epoxy equivalent of 220
To a uniform mixture of 80 parts by weight of O-cresol novolac epoxy resin and 20 parts by weight of bisphenol A epoxy resin having an average epoxy equivalent of 475, 1 part by weight of O-cresol novolak epoxy resin was added.
A mixture prepared by adding 20.5 parts by weight of 06 phenol novolac resin and 0.5 parts by weight of triethylamine, heating and mixing was used.

On the other hand, the dimensions are 300x300+ma and the thickness is 0.2 am
A comb-shaped electrode consisting of 12 pairs of electrodes with an inter-electrode pitch of 4 mm, an electrode length of 20 aoi, and an electrode width of 1 mm was produced by punching a copper plate. After that, as shown in Fig. 1, the comb-shaped electrodes 1 are placed in a mold so that the electrode length (wrap length) 3 of the part where the inter-electrode distance 2 is wrapped by lams is 15 mmK, and then heated to 130°C. The heated resin composition was heated to 17
The mixture was injected into a mold at 0° C. to fill the spaces between the electrodes and coat the electrodes to obtain a rectangular parallelepiped-shaped molded product with a thickness of 5 ann and dimensions of 60×30 mm.

The molded product was deasphalted from the mold in 5 minutes at 170°C, and
It was cured for 3 hours at 5°C.

A bias voltage of 500 V was applied to the shaped electrode, and the product was left in an atmosphere of 65° C. and 90 SRH for 300 hours. The initial insulation resistance was 4 x 1014 Ω, which decreased to 3 x 10” Ω after 300 hours, but there was no corrosion of the comb-shaped electrodes, and even when observing the area between the comb-shaped electrodes with a microscope at 40x magnification, no copper due to electrolytic corrosion was observed. No dendrites were observed.

Comparative Example 2 To 100 parts by weight of the same epoxy resin composition as in Example 2, 80 parts by weight of the same alumina powder as in Example 1, which was not treated with a corrosion inhibitor, was added to prepare a resin composition. Thereafter, in the same manner as in Example 2, a resin composition was filled between the electrodes and the periphery of the electrodes was covered with the resin composition to obtain a rectangular parallelepiped-shaped molded product. The curing conditions were the same as in Example 2.

A bias voltage of 500 V was applied to the formed comb-shaped electrode, and the electrode was left in an atmosphere of 65° C. and 90° RH for 300 hours.

The initial insulation resistance is 3 x 1014, 30
After 0 hours, it decreased to 1.5×1G”t.

A portion of the comb-shaped electrodes was corroded, and when the space between the comb-shaped electrodes was observed under a microscope with a magnification of 40 times, copper dendrites due to electrolytic corrosion were observed.

(Effects of the Invention) The resin composition of the present invention prevents corrosion of nine electrode circuits formed on the surfaces of wiring boards, electronic components, etc.

It is a resin composition that can eliminate defects caused by electrolytic corrosion, etc., does not cause cracks, and is extremely suitable as a protective film.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a state in which interdigitated electrodes are placed facing each other in a mold. Explanation of symbols 1...Comb-shaped electrode 2...Distance between electrodes 3...
・Electrode length of the wrapped part Patent attorney Kunihiko Wakabayashi Figure 1

Claims (1)

[Claims] 1. 5 to 60% of inorganic powder treated with corrosion inhibitor in the entire composition
A resin composition containing % by weight.