| 摘要 |
PURPOSE:To provide a fine gel heating medium which is prevented from caking during cooling, can comfortably be used with good flexibility and exhibits good stability with time to a repeated heating-coolig cycle, by dispersing a powdered highly water-absorbing resin in an aq. medium. CONSTITUTION:0.5-10wt% powdered highly watr-absorbing resin (having a water absorption ability of 100 times or more) such as a polyvinyl alcohol resin [which is crosslinked by ester linkage and contains carboxyl group on its side chain (usually, the carboxyl group is neutralized with an alkali metal or ammonia to form a salt)] is dispersed in an aq. medium. As said aq. medium, water may be used, but it is preferred to use a water-lower alcohol mixed solvent (having an alcohol concn. of 2-70vol%) in order to impart flexibility to the heating medium when used at a low temp. of not higher than 0 deg.. This heating medium is suitable for use as a heat insulating agent in a hot-water bottle (a foot warmer), a poultice, an ice pillow, etc. |
