Thermographic recording process

Abstract

Abstract INFORMATION IS REPRODUCED BY THE STEPS OF EXPOSING TO A MAINLY VISIBLE LIGHT IMAGE A RECORDING LAYER CONTAINING AT LEAST ABOUT 80% BY WEIGHT OF A NORMALLY WATER-SOLUBLE POLYMER OF CERTAIN SELECTED TYPES WHICH IS SUBSTANTIALLY INSENSITIVE TO VISIBLE LIGHT BUT WHEN HEATED UNDERGOES A LOSS IN ITS NORMAL SOLUBILITY IN AQUEOUS SOLVENTS AND CONTACTING THE EXPOSED RECORDING LAYER WITH AN AQUEOUS SOLVENT FOR THE PURPOSE OF REMOVING THE UNEXPOSED SOLUBLE AREAS THEREOF THEREBY LEAVING A RELIEF IMAGE CORRESPONDING TO THE ORGINAL. THE RECORDING LAYER CONTAINS UNIFORMLY DISTRIBUTED THERETHROUGH A FINELY DIVIDED SUBSTANCE THAT ABSORBS AND CONVERTS VISIBLE RADIATION INTO HEAT, THE AMOUNT OF SUCH SUBSTANCE BEING SUFFICIENT TO IMPART TO THE RECORDING LAYER AN OPTICAL DENSITY OF ABOUT 0.2-1 IN THE EVENT REFLEX EXPOSURE IS PRACTICED OR OF AT LEAST ABOUT 0.2 IN THE EVENT THE EXPOSURE IS DIRECT. THE RECORDING LAYER IS SUBSTANTIALLY TRANSPARENT EXCEPT FOR THE RADIATION ABSORBING AND CONVERTING SUBSTANCE. THE TIME OF THE EXPOSURE DOES NOT EXCEED 10-2 SECONDS, AND THE INTENSITY OF THE RADIATION IS SUFFCIENTLY LARGE AS TO GENERATE WITHIN THAT TIME BY VIRTURE OF THE ABSORPTION AND CONVERSION EFFECT OF THE SUBSTANCE SUFFICIENT HEAT TO PRODUCE A LOSS IN SOLUBILITY IN THE POLYMER IN THE EXPOSED AREA.

Inventors

• 👤 Eric Maria Brinckman

Bibliographic Details