COLOUR DEVELOPING COMPOSITIONS AND RECORDING MATERIAL CONTAINING SAID COMPOSITIONS Russian patent published in 2012 - IPC B41M5/333 

FIELD: chemistry.

SUBSTANCE: disclosed is a colour developing composition for recording materials, which is a reaction composition containing a mixture of compounds of formula (III) obtained from reaction of a dihydroxy diphenyl sulphone derivative of formula (I) with a dihalide of formula (ll), X-Y-X (II), where in the composition, at least 10 wt. % of the compound with n=1 is a crystalline material when content of the compound with n=1 in said reaction composition ranges from 5 to 80 wt. % of the total dry residue of the composition.

EFFECT: disclosed colour developing composition increases heat resistance.

9 cl, 8 dwg, 4 tbl, 14 ex