Xanthene derivative and a production process of the same

Abstract

This invention relates to a xanthene derivative that develops color on oxidation, so that it is favorably used for a photoresist, a PS plate or a proofing agent. The xanthene derivative, which has the following structural formula (I), is produced by putting a fluoran derivative represented by the following structural formula (II) to an esterification reaction and then to a reduction reaction. ##STR1## In the above formulae R.sub.1 and R.sub.2 independently stand for hydrogen, an alkyl radical with 1 to 8 carbon atoms, a tetrahydrofurfuryl radical, a substitued or an unsubstituted phenyl radical, a substituted or an unsubstituted benzyl radical or a cyclic alkyl radical; in addition, R.sub.1 and R.sub.2 are able to form a ring in pairs. R.sub.3 and R.sub.6 independently stand for hydrogen, chlorine, fluorine, a lower alkyl radical or a lower alkoxy radical. R.sub.4 and R.sub.5 independently stand for hydrogen, chlorine, fluorine, a lower alkyl radical, a lower alkoxy radical, a lower alkoxyalkyl radical, a substituted or an unsubstituted phenyl radical, a substituted or an unsubstituted benzyl radical, an amino radical, a N-substituted or N,N-substituted amino radical or a cyclic alkyl radical; in addition, R.sub.3 and R.sub.4, R.sub.4 and R.sub.5, and R.sub.5 and R.sub.6 are able to form a ring in pairs respectively. R.sub.7 stands for an alkyl radical, a substituted or an unsubstituted phenyl radical or a substituted or an unsubstituted benzyl radical. X stands for hydrogen, chlorine, fluorine, bromine, a nitro radical, a lower alkyl radical or a lower alkylamino radical; and n stands for an integer from 1 to 4 inclusive.