CHARGE CONTROLLING AGENT FOR ELECTROSTATIC CHARGE IMAGE DEVELOPMENT, AND TONER AND CHARGE IMPARTING MEMBER USING THAT

摘要

PROBLEM TO BE SOLVED: To obtain a high-quality toner for electrostatic charge image development which is excellent in electrification stability and hardly causes contamination on a copy by using barium sulfate or a compd. having a specified structure as a charge controlling agent. SOLUTION: This charge controlling agent for electrostatic charge image development consists of barium sulfate or a compd. expressed by [A-(-SO3 )2 ]Ba, and this agent is used to obtain a toner and a charge imparting member. In formula, A is an aromatic ring residue which may have substituents. As for the aromatic ring residue, arylene groups such as phenylene and naphthylene groups can be used, and especially, naphthylene groups are preferable. The residues may have 1 or more substituents except for a sulfonyl group, the substituents are 1-6C alkyl groups, hydroxyl groups, etc., and especially hydroxyl groups are preferable. Or the residues may have two or more kinds of substituents or a plural number of the same substituents. Especially, barium sulfate is preferable because it is excellent in characteristics as required and safe for a human body.