PURPOSE: To provide an electrochromic display device (ECD) which prevents failure owing to thermal expansion of an electrolyte during the use of the ECD at a high temp. and which does not produce foam during the use at a room temp. or further at a low temp. with respect to the ECD which utilizes electrochemical coloring and erasing reaction.
CONSTITUTION: 11 is three-layered laminated thin films formed by using a sheet consisting of a hydrolyzed ethylene-vinyl acetate copolymer film of 15μ and a low gas transmission rate laminated on both surfaces thereof with low density PE (60μ) having good thermal adhesive strength and biaxially oriented PP (20μ) having a m.p. higher than that of PE and having electrolyte resistance, and adhering said sheet thermally with a heat sealer in such a way as to position the PE layer on the inner layer. A gas 12 such as gaseous nitrogen is sealed in the space formed in said thin films, whereby a reversible elastic body is constituted. When the ECD is manufactured by sealing such elastic body 11 in the inside of the ECD and injecting an electrolyte 8 through an injection port 9 for the electrolyte, no foam is produced despite exposure to an atmosphere of high and low temps. for a long period of time.
HATSUTORI KATSUJI
YOSHINO YOUZOU
