| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the generation of thermal deformation in a disk by using a toner having a softening temp. equal to or below a thermal deformation temp. of the desk. SOLUTION: The toner having the softening temp. equal to or below the thermal deformation temp. of the disk is used. The difference between the thermal deformation temp. of the disk and the softening temp. of the toner is >=1 deg.C, preferably >=2 deg.C and further desirably >=5 deg.C in the view point of greatly improving the fixing strength of the toner. The softening temp. of the toner is changed by changing the kinds of a binder resin used for the toner to give a prescribed softening temp. and the softening temp. of the binder resin is >=80 deg.C, desirably 190 deg.C. As the representative example of the binder resin, a polyester, a styrene-acrylic ester based resin and the like are mentioned. The polyester suitably used in the binder resins is obtained by the polycondensation reaction of a polyvalent carboxylic acid with a polyhydric alcohol.</p> |
