| 摘要 |
PURPOSE:The title toner which is excellent in fixability and adaptability to offset printing and can prolong the life of a photosensitive material, obtained by mixing a polyester resin synthesized in the presence of a metal-free catalyst with a colorant. CONSTITUTION:A polyester resin of a chloroform-insoluble matter content >=5wt% is obtained by polycondensing an alcohol (e.g., ethylene glycol) with a carboxylic acid (e.g., terephthalic acid) and, optionally, 30-80mol%, based on the alcohol component, at least trifuctional monomer (e.g., sorbitol) and 30-80mol%, based on the acid component, at least tribasic carboxylic acid monomer (e.g., 1,2,4-benzenetricarboxylic acid) in the presence of a metal-free catalyst (e.g., toluenesulfonic acid) is mixed with a colorant (e.g., carbon black) and, optionally, additives such as an offset preventing agent and a charge controller, and 0.01-10wt% hydrophobic fine silica powder. The obtained mixture is kneaded, ground and classified to obtain the title toner of a particle diameter of 1-50mum. |
