| (19) |
 |
|
(11) |
EP 0 402 882 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
16.01.1991 Bulletin 1991/03 |
| (43) |
Date of publication A2: |
|
19.12.1990 Bulletin 1990/51 |
| (22) |
Date of filing: 13.06.1990 |
|
| (51) |
International Patent Classification (IPC)5: G03G 9/08 |
|
| (84) |
Designated Contracting States: |
|
BE DE FR GB |
| (30) |
Priority: |
14.06.1989 JP 151276/89
02.08.1989 JP 200981/89
|
| (71) |
Applicant: BANDO CHEMICAL INDUSTRIES, LIMITED |
|
Hyogo-ku
Kobe-shi (JP) |
|
| (72) |
Inventors: |
|
- Nonaka, Keizo,
c/o Bando Chemical Industries, Ltd.
Hyogo-ku,
Kobe (JP)
- Yamashiro, Jiro,
c/o Bando Chemical Ind. Ltd.
Hyogo-ku,
Kobe (JP)
- Yamaguchi, Katsuya,c/o Bando Chemical Ind. Ltd.
Hyogo-ku,
Kobe (JP)
|
| (74) |
Representative: von Kreisler, Alek, Dipl.-Chem. et al |
|
Patentanwälte
von Kreisler-Selting-Werner
Postfach 10 22 41
50462 Köln
50462 Köln (DE) |
|
| |
|
| (54) |
Master batch for production of toners used in electrophotography |
(57) A method of producing a master batch for the production of toners used in electrophotography
is disclosed, which comprises: mixing and kneading a binder resin in an amountof 100
parts by weight, at least one of dyes and pigments in an amount of 1-300 parts by
weight and an organic solvent in an amount of 5-500 parts by weight in which the binder
resin is soluble, and then, optionally crushing or granulating the mixture.
There is further disclosed a method of producing toners for use in electrophotography
which comprises: adding 100 parts by weight of a second binder resin to 2-20 parts
by weight of the master batch together with an effective amount of an additive when
necessary, to form a second mixture, kneading the second mixture to a composition;
and
(c) crushing the composition to toner particles.