| (19) |
 |
|
(11) |
EP 0 564 287 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
23.03.1994 Bulletin 1994/12 |
| (43) |
Date of publication A2: |
|
06.10.1993 Bulletin 1993/40 |
| (22) |
Date of filing: 01.04.1993 |
|
| (51) |
International Patent Classification (IPC)5: C23C 22/36 |
|
| (84) |
Designated Contracting States: |
|
DE FR GB |
| (30) |
Priority: |
03.04.1992 JP 82509/92
|
| (71) |
Applicant: Nippon Paint Co., Ltd. |
|
Kita-ku,
Osaka-shi,
Osaka 531 (JP) |
|
| (72) |
Inventors: |
|
- Jo, Masahiro
Moriguchi-shi,
Osaka 570 (JP)
- Mino, Yasutake
Kobe-shi,
Hyogo 658 (JP)
- Sobata, Tamotsu
Shirakawa,
Ibaraki-shi,
Osaka 567 (JP)
|
| (74) |
Representative: Murgitroyd, Ian G. et al |
|
Murgitroyd and Company
373 Scotland Street
Glasgow G5 8QA
Glasgow G5 8QA (GB) |
|
| |
|
| (54) |
Method for zinc-phosphating metal surface to be treated by the cationic electrodeposition
coating |
(57) By using a zinc-phosphating solution, which does not contain a nickel ion, but contains
0.1 to 4 g/l of a cobalt ion, 0.1 to 3 g/l of a manganese ion, a phosphating accelerator,
200 to 500 mg/l of a simple fluoride compound in terms of HF concentration and a complex
fluoride compound in a mole ratio of 0.01 to 0.5 relative to the simple fluoride compound,
a zinc phosphate coating film suitable for cationic electrodeposition coating and
superior in coating film adhesiveness and corrosion resistance, especially in warm
brine resistance and scab resistance, is formed on the metal surface simultaneously
having an iron-based, a zinc-based and an aluminum-based surface by using an identical
solution.