Water soluble thioxantone photoinitiators
Abstract
Abstract The invention provides novel thioxanthone photoinitiators having the formula: ##STR1## wherein R 1 alkyl, alkoxy, alkylthio, halogeno, nitro, amino, alkyl-amino, di-alkyl-amino, hydroxy alkyl-amino, alkanoylamino, benzoylamino, N-alkanoyl-N-benzoyl-amino, sulphonamido, or acetyl, R 2 is alkylene, A is --COOH, --SO 3 H, --OSO 3 H, or --O--CO--X--COOH (where X is such that HO--CO--X--COOH is a di- or tri-carboxylic acid of up to 8 carbon atoms), n is 0, 1, or 2 and m is 1 or 2, provided that when A is --COOH, m is 2, the aforesaid alkyl, alkoxy, alkanoyl, and alkylene residues containing up to 4 carbon atoms each, as the free acid or as a salt thereof. The photoinitiators may advantageously be used in water-based photopolymerizable compositions, e.g. for use in screen stencil production.
Inventors
- 👤 John R. Curtis
- 👤 Peter E. Heaton
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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