Particulate electrophotographic toner material

Claim 1

Particulate toner material for use in the development of latent electrostatic images, wherein said particulate toner material is capable of acquiring by triboelelectric contact electrification a net positive charge and contains thermoplastic resin(s) as binder in combination with a colorant and a colourless compound capable of imparting a positive charge to the particulate toner material in contact electrification, characterized in that said colourless compound corresponds to the following general Formula (A) or is a polymer consisting essentially of repeating units according to general formula (B) or is an amine-salt or quaternary ammonium derivative thereof: ##STR12## wherein: each of R 1 , R 2 , R 3 and R 4 independently of each other, stands for a 1-6C alkyl group, R 5 represents hydrogen or a 1-5C alkyl group, R 6 represents hydrogen, a 1-12C alkyl group, a 3-12 C alkenyl group, or a 7-12C aralkyl group, m is 1 to 4, and R 7 represents where m is 1 an acyl group, a N-substituted carbamoyl group or a N-substituted thiocarbamoyl group, where m is 2 a carbonyl thiocarbonyl or a diacyl group, a N-substituted dicarbamoyl group or a N-substituted dithiocarbamoyl group, where m is 3 a triacyl group, a N-substituted tricarbamoyl group or a N-substituted trithiocarbamoyl group, and where m is 4 a tetraacyl group, a N-substituted tetracarbamoyl group or a N-substituted tetrathiocarbamoyl group, the N-substituents of said carbamoyl and thiocarbamoyl groups being a hydrocarbon group or a heterocyclic group, and R 8 represents hydrogen an alkyl group or an aralkyl group, or R 7 and Rhu 8 together represent the necessary atoms to close a saturated heterocyclic nitrogen containing ring; ##STR13## wherein: each of R 1 , R 2 , R 3 and R 4 , independently of each other, stands for a 1-6C alkyl group, R 5 represents hydrogen or a 1-5C alkyl group, R 6 represents hydrogen, a 1-12 C alkyl group, a 3-12C alkenyl group, or a 7-12C aralkyl group, each of A and B, independently of each other, represents a 2-12C alkylene group, 7-18 aralkylene group, a 5-12 cycloalkylene group or an arylene group, and n is 2 to 200.