Colour formers
Abstract
Abstract Colourless colour formers which are compounds characterised by the general formula: WHEREIN R1, R2 and R3 each independently represents hydrogen, an optionally substituted alkyl radical having from one to five carbon atoms or forms part of a heterocyclic ring containing the attached nitrogen atom; R4 represents a halogen atom or an alkyl, aryl, aralkyl, alkoxy, nitro, optionally substituted amino, acyl, carboxy, cyano or sulphamyl radical; n represents an integer of from 0 to 4; A represents an optionally substituted aromatic ring the points of attachment being at two pairs of ortho positions; Y represents a direct link, optionally substituted methylene, oxygen, sulphur or a group of the formula -NR6- wherein R6 denotes hydrogen or an optionally substituted alkyl, aryl or aralkyl radical; and Z represents an optionally substituted divalent organic radical such that a five-or six-membered ring is formed with Y, -NR3- and A.
Inventors
- 👤 N Hughes
- 👤 A Renfrew
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
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