Abstract A process for the preparation of printing plates from electrophotographic reproduction material, having a support suitable for printing purposes and a photoconductive layer thereon, by charging, imagewise exposure to light, developing the latent electrostatic image on the layer with a finely divided toner, subsequent heating, and removal of the photoconductive layer in the nonimage areas. The latent electrostatic image is produced on a layer which contains at least one known polymerizable organic photoconductor containing or forming during heating olefinic double bonds, and the image is made visible by means of a developer which, at least partially, consists of one or more finely divided solid substances forming radicals when heated. The reproduction material with the developed image thereon is heated to a temperature between 50* and 300* C., preferably to a temperature between 100* and 200* C., and finally the organic photoconductive layer is removed, in known manner, in the nonimage areas by dissolving it away.
A process according to claim 1 in which the photoconductive insulating layer comprises a polymerizable organic photoconductor containing vinyl groups in admixture with an alkali-soluble binding agent, and the photoconductive layer is removed from the support in the nonimage areas by treatment with an aqueous alkaline liquid.
Claim 2
Dependent Claim
31 words
A process according to claim 1 in which the finely divided material which forms radicals when heated is contacted with the latent electrostatic image in the form of a dry powder.
Claim 3
Dependent Claim
34 words
A process according to claim 1 in which the finely divided material which forms radicals when heated in contacted with the latent electrostatic image in the form of a dispersion in a dielectric liquid.
Claim 4
Dependent Claim
25 words
A process according to claim 1 in which the polymerizable organic photoconductor is selected from the group consisting of vinylcarbazoles, vinyloxazoles, vinyltriazoles, vinyldibenzofuran, and hydroxyethyl-diphenyltriazoles.
Claim 5
Dependent Claim
39 words
A process according to claim 1 in which the finely divided material which forms radicals when heated is selected from the group consisting of benzoyl peroxide, dichlorobenzoyl peroxide, succinyl peroxide, azoisobutyric nitrile, tetraphenyl hydrazine, dehydrolophine, diazidostilbene, and sodium trichloroacetate.