HEAT-SENSITIVE IMAGE RECORDING MEDIUM AND PROCESS

摘要

Certain squaric acid derivatives and sulfonate esters are useful for the thermochemical generation of acid. The thermal acid generators may be used in imaging media in conjunction with acid-sensitive materials which undergo a color change when contacted by the acid generated. Preferably, the acid-sensitive materials undergo an irreversible color change, so that the image can be fixed by neutralizing all the acid generated with excess base, thereby preventing further color change in the image during long term storage.