| 摘要 |
PURPOSE:To improve the developability of a photosensitive composition when the composition is developed with an aqueous alkali developer, by incorporating polyurethane having carboxyl groups. CONSTITUTION:This photosensitive composition contains a diazonium compound and polyurethane resin having carboxyl groups. Diazo resin prepd. by condensing an aromatic diazonium salt with a compound having an active carbonyl group such as formaldehyde may be used as the diazonium compound. A product prepd. by reacting a diisocyanate represented by formula I with a diol having a carboxyl group represented by formula II or III may be used as the polyurethane. In the formulae I-III, each of R1 and R3-R5 is bivalent aliphatic or aromatic hydrocarbon, R2 is H, alkyl or the like, and Ar is tervalent aromatic hydrocarbon. When the composition is developed with an alkaline developer after exposure, it has high developability and gives a relief image having improved wear resistance, sensitizability and adhesion to the support. |
