Copyright © 1981 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Polyimide resin of solvent-soluble type, which is called “X-resin” in short, was discovered lately. It is soluble in dimethylacetoamid (DMAc), and new extensive applications are expected.

Some physical, chemical and electrical characteristics are studied from the viewpoint of polymer material for hybrid application. Particularly comparison of the characteristics of X-resin specimens before and after long term exposure to humid and hot environments were made, remembering that electronic devices often operate under such conditions in Japan.

From the results obtained up to now, no conspicuous difference seems to exist between the characteristics of X-resin and those of the conventional (i.e., solvent-insoluble) resins, as published in various literature. It should be noted, however, that some unusual effects, i.e., the remarkable increase in surface resistivity σ, the evident decrease in tan δ, etc., were found in X-resin specimens after going through the above-mentioned damp-hot test. All those effects are contrary to the usual concepts of deterioration of polymer materials, but are rather advantageous for hybrid application. It is also worth noticing that silver migration into X-resin seems scarcely to occur.

Furthermore, new prospective uses of X-resin for printed wiring boards, packaging materials, binder for paste materials, etc., are investigated.