Abstract: A composition for coating a substrate for use in an image wise developable or transferal system comprises (I) a free base of a cationic solvent dye capable of developing a color or at least a more intense color upon reaction with an organic acid developing compound and (II) a binder which is a wax or resin which does not develop said free base and which has been mixed with said free base in the presence of a non developing substantially non-polar solvent. Various forms of coating including the color developer composition in a layer or particulate form are applicable to different end uses.

Abstract: An image wise developable sheet which develops in an image wise fashion areas of the coated substrate thereof to which there has been an image wise selective application of pressure, heat, light or electrical discharge. The coating which is developable comprises (1) a free base of a cationic solvent dye capable of developing a colour or at least a more intense colour upon reaction with an organic acid developing compounds and (11) a binder which is a wax or resin which does not develop said free base and which has been mixed with said free base in the presence of a non-developing substantially non-polar solvent. Various forms of coating thereof including the colour developer composition in a layer or particulate form are applicable to different end uses.

Abstract: An imagewise developable system comprising (I) a substrate supported presence of a mixture of a free base of a cationic solvent dye capable of developing a color or a more intense color upon reaction with an organic acid developing agent and a non developing binder and (II) a substrate supported organic acid developing agent not in the reactive presence of said free base of solvent dye but selectively migratable to imagewise develop the free base under an action selected from the group consisting of applying selective imagewise pressure to the system, applying selective imagewise heat to the system and applying selective electrical discharges to the system.