Importance

Loading Importance Indicators...

Abstract

The present invention provides a method that enables the use of an aqueous solution of a copolymer of vinyl alcohol and an alkali metal neutralized product of ethylenically unsaturated carboxylic acid or carboxymethyl cellulose or a salt thereof, as a binder for secondary batteries, without causing a significant viscosity increase even if stored in the state of an aqueous solution. More specifically, the present invention provides a composition in the form of an aqueous solution containing a copolymer of vinyl alcohol and an alkali metal neutralized product of ethylenically unsaturated carboxylic acid and/or carboxymethyl cellulose or a salt thereof, wherein when the viscosity of the composition after being diluted with water (25° C. or less) to a viscosity of 200±100 mPa·s at room temperature (25° C.) and being adjusted to a temperature of 25° C. is defined as X^a1 (Pa·s), and the viscosity of the composition after being placed in an airtight container and being allowed to stand at 95° C. for 8 hours is defined as X^b1 (Pa·s), the change rate obtained by the following formula:

description='In-line Formulae' end='lead'Change rate (%)=(X^a1−X^b1)/X^b1×100description='In-line Formulae' end='tail'

is 0 to 10%.

Loading the Abstract Image...

First Claim