JPS61113641A - Phenolic resin composition for electrolytic corrosion resistance use - Google Patents

Abstract

PURPOSE:To obtain the titled composition free from ammonia suitable for electronic parts such as coil bobbins non-corrosive to various metals such as copper even if used under high temperature-high humidity conditions for a long time, by regulating the chlorine ion in the composition so as to keep its concentration constant. CONSTITUTION:The objective phenolic resin composition free from ammonia with the chlorine ion concentration therein retained <=300ppm. This composition can be obtained by incorporating (A) 40-50pts.wt. of a resol-type phenolic resin with (B) 50-60pts.wt. of filler comprising clay, talc, aluminum hydroxide and calcium carbonate, (C) 2pts.wt. of pigment carbon black and (D) 1.5pts.wt. of lubricating agent, followed by kneading using a hot roll.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a phenolic resin composition that has excellent electrolytic corrosion resistance against copper or other free metals used in electronic parts such as coil bobbins. .

[Prior art]

Phenolic resins have traditionally been used for coil bobbins due to their heat resistance, strength, and moldability, but copper wire is often used for coils, and novolac-type phenolic resins are susceptible to ammonia produced during the reaction. There is a problem in that copper wires are chemically corroded and disconnected. In order to deal with such problems, ammonia-free products have been developed using resol-type phenolic resins. However, in recent years, as electronic parts such as coil bobbins have become thinner and smaller, and wire rods have become ultra-fine, even ammonia-free materials can become
There has been a problem with electrochemical corrosion of copper wires.

[Purpose of the invention]

The present invention eliminates stain corrosion by reducing ionic impurities in the material, especially the amount of chlorine ions, which cause electrolytic corrosion, even with ammonia-free materials. The present invention was completed based on the knowledge obtained and the study conducted based on this knowledge.

The purpose is to provide a phenolic resin composition that causes less electrolytic corrosion of metals in electronic parts such as coil bobbins.

[Structure of the invention]

In the present invention, the chloride ion concentration in the resin composition is 300 p.
This is an electrolytic corrosion-resistant ammonia-free phenol resin composition characterized in that the electrolytic corrosion resistant ammonia-free phenol resin composition has a content of pm or less.

The chloride ion concentration referred to here is a value measured by potentiometric titration after extracting a sample with distilled water.

In carrying out the present invention, the stain-eating property is improved by suppressing ionic impurities such as ammonia and chlorine ions, which are factors that corrode copper wire, and here, raw materials with less ionic impurities are used. Select and mix. Therefore, the resins used are resol type phenolic resin,
As the filler, clay, Merck, aluminum hydroxide, and calcium carbonate having a low chloride ion content are preferred.

To explain the present invention in detail, clay is added as a filler to 40 to 50 parts by weight of a resol type phenolic resin.
Talc, aluminum hydroxide and calcium carbonate 50-60
i [parts by weight, 2 parts by weight of pigment carbon black, and 1.5 parts by weight of lubricant were blended and kneaded with hot rolls.

The obtained composition was molded into a block, and a copper wire was wound around it. An electrolytic corrosion model test was conducted to measure the disconnection time when a constant voltage was continuously applied in a constant temperature and humidity chamber. There was no disconnection for more than an hour.

With a novolac type phenolic resin composition, the corrosion breakage time is several tens of hours, and even with resol type ammonia-free materials, when fillers with high chlorine content such as asbestos and organic fibers are used, the wire breaks in about 100 hours. Ta.

According to the resin composition of the present invention, it was possible to obtain a disconnection life that is 10 times longer than that of a conventional product against electrolytic corrosion of the copper wire of a coil bobbin.

〔Effect of the invention〕

According to the present invention, when the conventional ammonia-free phenol composition was subjected to the test shown in Figure 1 under high temperature and humid conditions, the steel wire used as the winding wire broke in about 100 hours;
It had the effect of not breaking the wire for more than 0 hours.

It is suitable as a highly reliable composition for recent high-performance, miniaturized electronic components.

(Example-1) Roll kneading of resol type phenol [40 parts by weight of fat, 20 parts by weight of Lz-20, 20 parts by weight of aluminum hydroxide, 15 parts by weight of talc, 2 parts by weight of lubricant, 2 parts by weight of pigment, 2 parts by weight of slaked lime A composition was obtained.

(Example-2) 40 parts by weight of resol type phenolic resin, 20 parts by weight of calcium carbonate, part of aluminum hydroxide 201ii, 15 parts of talc
parts by weight, 2 parts by weight of lubricant, 2 parts by weight of pigment, and 2 parts by weight of slaked lime were mixed with rolls to obtain a composition.

(Comparative Example-1) 40 parts by weight of resol type phenol It fat, 10 parts by weight of Aspes, 103 parts by weight of magnesium hydroxide, 20 parts by weight of aluminum hydroxide, 10 parts by weight of organic fiber, 2 parts by weight of lubricant, 2 parts by weight of pigment, slaked lime 2 parts by weight was mixed with a roll to obtain a composition.

(Comparative Example-2) 40 parts by weight of novolac type phenolic resin, 20 parts by weight of clay, 20 parts by weight of aluminum hydroxide, 15 parts by weight of talc, 2 parts by weight of lubricant, 2 parts by weight of pigment, 5.3 parts by weight of hexamethylenetetramine. A composition was obtained by cross-rolling.

When we evaluated Examples 1 and 2 and Comparative Examples 1 and 2, we found that even with the cyanmonia-free phenol compositions shown in the table, those with a high chloride ion concentration had a short wire breakage time and a low chloride ion concentration. Even when the temperature was low, the wire broke in a short time even when it contained ammonia, such as a novolac type phenol resin composition.

According to the present invention, the ammonia-free phenol resin composition with reduced cyclochloride ions has an effect of increasing the disconnection time by more than 10 times.

Note 1) The chloride ion concentration is based on the measurement method described in the section of “Structure of the Invention”.

Note 2) 7/% near amount is based on ASTM D834K.

Note 3) In the electrolytic corrosion model test shown in Figure K1, the test piece block (2) was wrapped with copper wire (1) at regular intervals, placed under 90% high temperature humidification at 40°C, and DClooV was continuously applied to measure the disconnection time. do.

[Brief explanation of drawings]

FIG. 1 is a model test diagram used for electrolytic corrosion evaluation in the present invention. 1 is a copper wire, 2 is a test piece block.

Claims (1)

[Claims] An ammonia-free phenol resin composition for electrical corrosion resistance, characterized in that the chlorine ion concentration in the resin composition is 300 ppm or less.