| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a toner having a long service life, excellent in low temp. fixability and shelf stability and giving high image quality by incorporating a polyester resin having a specified acid value, a colorant, an electric charge controlling agent and a releasing agent and specifying the loss elastic modulus. SOLUTION: The toner contains a polyester resin having 5-30 mgKOH/g acid value, a colorant such as carbon black, an electric charge controlling agent such as a chromium complex salt and a releasing agent such as Fischer- Tropsch wax derived from natural gas and has 500-1,500 Pa loss elastic modulus G'' at 180 deg.C and 1 Hz. The polyester resin is preferably a urethane modified polyester resin synthesized by polycondensation reaction from a polyol such as polyoxyethylene (2,2)-2,2-bis(4-hydroxyphenyl)propane and a polycarboxylic acid such as fumaric acid. The toner preferably has 500-2,000 Pa storage elastic modulus G' at 180 deg.C and 1 Hz and a loss tangent of 0.7-1.0 at 180 deg.C and 1 Hz.</p> |
