Oblon, Fisher, Spivak, McClelland & Maier
Process for producing potassium hydroxide
 A process for producing potassium hydroxide by electrolysis of potassium chloride in an electrolytic cell comprising an anode compartment and a cathode compartment partitioned by a cation exchange membrane, which process comprises supplying potassium chloride to the anode compartment for the electrolysis to form potassium hydroxide in the cathode compartment, characterized in that said cation exchange membrane is a multi-layer membrane comprising at least two layers including a main layer made of a perfluorocarbon polymer having carboxylic acid groups as its ion exchange groups with an ion exchange capacity of from 0.9 to 1.6 meq/g dry resin and having a thickness of from 80 to 300 .mu.m and a sulfonic acid film surface layer on the anode compartment side, made of a perfluorocarbon polymer having sulfonic acid groups as its ion exchange groups with an ion exchange capacity of from 0.5 to 1.5 meq/g dry resin and having a thickness of from 5 to 50 .mu.m. 
Asahi Glass Company, Ltd.
C C
C08J C25B
inventional inventional
Haruhisa Hiroaki Ryoji Koji
Miyake Ito Yamada Suzuki