| (19) |
 |
|
(11) |
EP 0 936 507 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
17.11.1999 Bulletin 1999/46 |
| (43) |
Date of publication A2: |
|
18.08.1999 Bulletin 1999/33 |
| (22) |
Date of filing: 16.02.1999 |
|
|
| (84) |
Designated Contracting States: |
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AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
|
Designated Extension States: |
|
AL LT LV MK RO SI |
| (30) |
Priority: |
17.02.1998 JP 5282698
|
| (71) |
Applicant: TODA KOGYO CORP. |
|
Hiroshima-shi
Hiroshima-ken (JP) |
|
| (72) |
Inventors: |
|
- Hayashi, Kazuyuki
Hiroshima-shi,
Hiroshima-ken (JP)
- Morii, Hiroko
Hiroshima-shi,
Hiroshima-ken (JP)
- Tanaka, Yasuyuki
Onoda-shi,
Yamaguchi-ken (JP)
- Ishitani, Seiji
Hiroshima-shi,
Hiroshima-ken (JP)
|
| (74) |
Representative: Woods, Geoffrey Corlett |
|
J.A. KEMP & CO.
14 South Square
Gray's Inn
London WC1R 5LX
London WC1R 5LX (GB) |
|
| |
|
| (54) |
Black magnetic composite particles and black magnetic toner using the same |
(57) Black magnetic composite particles for a black magnetic toner comprising:
(a) magnetic iron oxide particles having an average particle diameter of from 0.055
to 0.95 µm;
(b) a coating on the surface of said magnetic iron oxide particles, comprising at
least one organosilicon compound selected from:
(1) organosilane compounds obtainable by drying or heat-treating alkoxysilane compounds,
(2) polysiloxanes or modified polysiloxanes, and
(3) fluoroalkyl organosilane compounds obtainable by drying or heat-treating fluoroalkylsilane
compounds; and
(c) carbon black fine particles adhered on at least a part of said coating, which
have a particle size of from 0.002 to 0.05 µm and which are present in an amount of
from 1 to 25 parts by weight per 100 parts by weight of said magnetic iron oxide particles.