Production of composite separation membrane

Abstract

Abstract PURPOSE:To obtain stably a composite sepn. membrane having high performance and heat resistance by coating a soln. of a silicone resin on the surface of a microporous arom. polyimide film which is beforehand produced, drying the coated layer thereof and removing gradually the solvent. CONSTITUTION: A microporous arom. polyimide film is produced by a dry filming or wet filming method wherein the arom. polyamic acid or soluble arom. polyimide obtd. by polymerizing an arom. tetracarboxylic acid component and an arom. diamine component is dissolved uniformly in an org. polar solvent and the soln. prepd. in such a way is used as a doping liquid. The method of coating a silicone resin soln. on a microporous film is exemplified by a coating method wherein the soln. is cast on the surface of the microporous film to a uniform thickness, a coating method wherein the soln. of a low viscosity is sprayed on the surface of the microporous film and a coating method wherein the microporous film is brought into contact with a roll wet with the soln.

Inventors

• 👤 Hiroshi Makino
• 👤 牧埜　弘
• 👤 Takashi Harada
• 👤 隆 原田

Bibliographic Details