Abstract: A graft copolymer of recurring units of (C.sub.6 -C.sub.18)alkyl (meth)acrylate (A), N-vinylpyrrolidone (B), glycidyl (meth)acrylate (C), and glycidyl (meth)acrylate units esterified with (meth)acrylic acid (D) onto which polymeric side chains of units of N-vinylpyrrolidone, (C.sub.1 -C.sub.3)alkyl acrylate and, if appropriate, (C.sub.1 -C.sub.3)alkyl methacrylate are grafted. The polymer is suitable as a binder for colorless, negatively chargeable liquid toners, in particular in combination with graft copolymers of (C.sub.1 -C.sub.6)alkyl (meth)acrylate, (C.sub.6 -C.sub.18)alkyl (meth)acrylate and units in which chains of N-vinyl-pyrrolidone units are grafted onto one of the units mentioned, as a charge control agent. After fixing of the electrophotographically produced toner image, the toners give colorless resist masks or printing screens with a high resistance toward etching agents and solvents.

Abstract: A process for the production of a colored image by an electrophotographic route by electrostatic charging, imagewise exposure to light and toning of a photoconductor material with a colorless transparent toner which includes a colorless polymeric binder and a colorless polymeric charge control agent, and transfer of the toner image to a colored layer which is soluble in a solvent and is on a layer carrier, fixing of the toner image and removal of the areas of the colored layer not covered by the toner image by washing out with a solvent. The process utilizes the high photosensitivity of electrophotographic materials, without the possibility of color falsification due to colored toners. The procedure is simpler compared with known electrophotographic processes, since the same toner can be employed in all steps and does not have to be washed off.

Abstract: The invention relates to a hydrophilic copolymer having the general structure:. . . --(A).sub.m -- . . . --(B).sub.n -- . . . --(C).sub.o -- . . . --(D).sub.p -- . . .in whichA is at least one polymerizable monomer having an acidic side group,B is at least one polymerizable monomer having a basic side group,C is at least one polymerizable monomer having a non-polar, non-hydrophilic side group, andD is at least one polymerizable monomer capable of increasing the hydrophilic character of monomer A or to form a chelate with monomer A,m, n, o and p are the monomer contents of monomers A, B, C and D, respectively, in mol %, with m+n+o+p=100 mol %, with the proviso that m and n are each.gtoreq.2 mol % and p is .gtoreq.1 mol %,wherein the copolymer is a linear copolymer having a random structure of the monomers. The copolymer is useful as a hydrophilizing agent for lithographic and offset printing plates, and as a binder in light-sensitive lithographic layers.

Abstract: The invention relates to a hydrophilic copolymer having the general structure: ##STR1## in which R.sup.1 denotes H, CH.sub.3 or C.sub.2 H.sub.5,R.sup.2 denotes an alkyl or cycloalkyl radical having 1 to 17 carbon atoms,R.sup.3 denotes CH.sub.3, C.sub.2 H.sub.5 or C.sub.3 H.sub.7,m is 2, 3 or 4 andn, o, p denote the fractions of the monomer units having acidic side groups, neutral, non-ionizable monomer units and monomer units having basic side groups respectively, in mol %, with n+o+p =100 mol %, with the proviso that n and p are each .gtoreq.5 mol %,wherein the copolymer is a linear copolymer having a random structure of monomer units. The copolymer is useful as a hydrophilizing agent for lithographic and offset printing plates.

Abstract: The invention relates to a thermally crosslinkable hydrophilic copolymer have the general structure:. . . --(A).sub.m --. . . --(B).sub.n --. . . --(C).sub.o --. . . --(D).sub.p --. . .in whichA is at least one polymerizable monomer having an acidic side group,B is at least one polymerizable monomer having a basic side group,C is at least one polymerizable monomer having a non-polar, non-hydrophilic side group, andD is N-butoxymethylmethacrylamide,m, n, o and p are the monomer contents of monomers A, B, C and D, respectively, in mol %, with m+n +o+p=100 mol %, with the proviso that the sum of m+n=about 5 to 90 mol %, m and n are each .gtoreq.2 mol % and p is .gtoreq.1 mol %,wherein the copolymer is a linear copolymer having a random structure of the monomers. The copolymer is useful as a hydrophilizing agent for lithographic and offset printing plates.

Abstract: The invention relates to a hydrophilic copolymer having the general structure: ##STR1## in which R.sup.1 denotes H, CH.sub.3 or C.sub.2 H.sub.5,R.sup.2 denotes an alkyl or cycloalkyl radical having 1 to 17 carbon atoms,R.sup.3 denotes CH.sub.3, C.sub.2 H.sub.5 or C.sub.3 H.sub.7,m is 2, 3 or 4 andn, o, p denote the fractions of the monomer units having acidic side groups, neutral, non-ionizable monomer units and monomer units having basic side groups respectively, in mol %, with n+o+p=100 mol %, with the proviso that n and p are each .gtoreq.2 mol %,wherein the copolymer is a linear copolymer having a random structure of monomer units. The copolymer is useful as a hydrophilizing agent for lithographic and offset printing plates.