Toyo Boseki Kabushiki Kaisha

Yohzo Yamada

Satoshi Maeda

Yasunari Hotta

Tetsuo Shimomura

Minako Arichi

Yoshihiro Ikuzawa

A toner for electrophotography which comprises, as a binder resin, a polyester resin obtained from carboxylic acids containing aromatic monomer in a proportion of 80 mol % or more relative to the entire carboxylic acid component, and alcohols containing aliphatic diols having 2 to 4 carbon atoms in a proportion of 70-100 mol % relative to the entire alcohol component and alicyclic alcohols in a proportion of 0-30 mol % relative to the entire alcohol component, and having a specific gravity of 1.3 or more, a glass transition temperature of 58.degree. C. or more, and a number average molecular weight of 1,000-6,000. The toner of the present invention is superior in image characteristics, fixability, storage stability (resistance to blocking), resistance to plasticizer and charge stability. Therefore, even after a long-term storage of a sheet copied using the toner of the present invention, by keeping same in direct contact with a vinyl chloride transparent sheet or an eraser, transfer of coloring materials and attaching of resin onto the vinyl chloride sheet or the eraser do not occur.

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Ohtsu, Japan

Yohzo Yamada