JPS61123620A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition having excellent adhesivity and moisture-proof insulation property and useful as a coating film for the pretection of a circuit board, by compounding specific amounts of an aminosilane coupling agent and 2-ethyl-4-methylimidazole to a base resin consisting of a thermosetting epoxy resin. CONSTITUTION:The objective composition can be produced by compounding (A) 100pts.(wt.) of a base resin consisting of a thermosetting epoxy resin with (B) 0.2-3pts. of an aminosilane coupling agent (e.g. gamma-aminopropyltriethoxysilane) and (C) 0.2-3pts. of 2-ethyl-4-methylimidazole as a cure accelerator.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a resin composition for a protective film on a circuit board used in radio receivers and television receivers.

BACKGROUND OF THE INVENTION Conventionally, resin compositions for protective coatings on circuit boards constituting radio receivers and television receivers have been required to have excellent adhesion to the substrate and moisture-proof insulation properties, and epoxy resin compositions, Acrylic resin compositions, urethane resin compositions, etc. are used.

These protective coating resin compositions are used for copper-clad laminates.

After forming a predetermined circuit conductor on a thin-film/thick-film hybrid integrated circuit board, a pattern for a protective film is screen printed and cured under predetermined curing conditions.

Typically, curing is performed at a curing temperature of 120''C to 200'C.
It took 6 minutes to 2 hours.

Problems to be Solved by the Invention When conventional resin compositions are used, a curing time of at least 16 minutes or more is required, resulting in a long production time. Further, when the curing time of conventional resin compositions is shortened, for example, at 200° C. for 6 minutes, the moisture-proof insulation properties deteriorate, making the compositions unsuitable for practical use.

The present invention solves these problems and provides a resin composition that can shorten the curing time and has excellent moisture-proof insulation properties.

Means to Solve the Problems The resin composition of the present invention contains 0.2 to 3 parts by weight of an aminosilane polishing agent and a polishing accelerator to 100 parts by weight of a base resin made of a thermosetting epoxy resin. It contains 0.5 to 3 parts by weight of 2-ethyl-4-methylimidazole.

Function The resin composition of the present invention contains a base resin made of a thermosetting epoxy resin, an aminosilica 7 coupling agent that improves the adhesion to the circuit board, and 2-ethyl-4-methylimidazole that accelerates the curing reaction. By adding and blending them in the appropriate proportions, excellent moisture-proof insulation properties can be obtained compared to when each is added alone.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings and tables. In this example, the base resin is a thermosetting epoxy resin, such as C-467G manufactured by Shikoku Kasei.

An aminosilane coupling agent such as γ-aminoethoxy-γ-aminopropyltrimethoxysilane and N-β-aminoethoxy-γ-aminopropyltrimethoxysilane is added in an amount of 0.2 to 3 times per 100 parts of Asahi Kaken C1-20 or the like. Department,
The curing accelerator 2-ethyl-4-methylimidazole was added to 0.
The ingredients added at a ratio of 5 to 3 parts by weight were thoroughly stirred and mixed.

Next, after forming a comb-shaped conductor pattern with a line width and spacing of 0.2jff using conductors 2 made of silver-palladium on the ceramic substrate 1 shown in FIG. 1, the resin composition 3 was cured under the conditions shown in Table 1. . Curing was determined by differential thermal analysis of the prepared sample cured resin composition based on the presence or absence of exothermic peaks in unreacted areas. As shown in Fig. 2 &, if the curing was complete, no exothermic peak appeared, and as shown in Fig. fiJ2, if the curing was insufficient, an exothermic peak was observed due to uncured.

The adhesion between the cured resin composition and the circuit board was determined according to JIS D-0202 after boiling the prepared sample in water for 5 hours.
, 8-12, and the adhesion was determined based on the peeled area ratio. Moisture-proof insulation properties were determined by applying a voltage of 30 V to the prepared sample in a high temperature and high humidity environment of 60"C/90%, and determining the silver migration rate generated from the silver/palladium conductor after 1000 hours. , adhesion and moisture-proof insulation properties are based on differential thermal analysis results under each addition condition.
The test was carried out under the optimum curing conditions.

As is clear from Table 1, the protective film made of paste resin alone (sample number 1) is not satisfactory in terms of adhesion and moisture-proof insulation. When 2-ethyl-4-methylimidazole was added to the base resin (sample number 2.3) and when an aminosilane coupling agent was added (sample number 4).
．． 6) Both have insufficient moisture-proof insulation.

In the case of the addition ratio of the present invention, (sample number 7,8゜11
．． 12) For the first time, the curing time is short and both adhesion and moisture-proof insulation properties are suitable for practical use. In addition, resin compositions outside the additive blending ratio of the present invention (sample numbers 8, 9, 1)
0.13), the curing time was long and the adhesion and moisture-proof insulation properties were insufficient, making it unsuitable for practical use.

Effects of the Invention As described above, the resin composition of the present invention has excellent adhesion and moisture-proof insulation properties, and can shorten curing time, thereby improving productivity and being extremely advantageous in practice.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a circuit board coated with the resin composition of the present invention, and FIGS. 2a and 2b are differential thermal analysis charts showing the cured state of the resin. 3...Coating resin. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure: A1/X (・c)

Claims (1)

[Claims] 0.2 to 3 parts of aminosilane coupling agent is added to 100 parts by weight of the base resin made of thermosetting epoxy resin.
Part by weight, 0.2 of 2-ethyl-4-methylimidazole
A resin composition characterized in that it is blended in a proportion of ~3 parts by weight.