| (19) |
 |
|
(11) |
EP 0 357 042 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
06.11.1991 Bulletin 1991/45 |
| (43) |
Date of publication A2: |
|
07.03.1990 Bulletin 1990/10 |
| (22) |
Date of filing: 30.08.1989 |
|
|
| (84) |
Designated Contracting States: |
|
AT BE DE FR GB IT NL |
| (30) |
Priority: |
30.08.1988 JP 213812/88
15.06.1989 JP 152978/89
|
| (71) |
Applicant: TDK Corporation |
|
Chuo-ku,
Tokyo-to 103 (JP) |
|
| (72) |
Inventors: |
|
- Aoki, Kazuo
c/o TDK Corporation
Tokyo (JP)
- Kakinuma, Akira
c/o TDK Corporation
Tokyo (JP)
- Saito, Megumi
c/o TDK Corporation
Tokyo (JP)
- Makino, Motohiko
c/o TDK Corporation
Tokyo (JP)
|
| (74) |
Representative: Vogeser, Werner, Dipl.-Ing. et al |
|
Patent- und Rechtsanwälte
Hansmann, Vogeser, Dr. Boecker,
Alber, Dr. Strych, Liedl
Albert-Rosshaupter-Strasse 65
D-81369 München
D-81369 München (DE) |
|
| |
|
| (54) |
Composition and method for developing electrostatic latent images |
(57) A composition for developing electrostatic latent images in electrographic printing
or copying machinery is provided in which 10% to less than 40% by weight of a carrier
having a mean particle diameter of from 10 to 35 µm is blended with a magnetic toner
comprising magnetic powder and a resin. Conventional charge control agents, especially
metal complexes of azo dyes and Nigrosine dyes should be excluded from the magnetic
toner.