| (19) |
 |
|
(11) |
EP 1 116 803 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
02.05.2003 Bulletin 2003/18 |
| (43) |
Date of publication A2: |
|
18.07.2001 Bulletin 2001/29 |
| (22) |
Date of filing: 10.01.2001 |
|
|
| (84) |
Designated Contracting States: |
|
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
Designated Extension States: |
|
AL LT LV MK RO SI |
| (30) |
Priority: |
12.01.2000 JP 2000003623
04.01.2001 JP 2001000149
|
| (71) |
Applicant: Nippon Paint Co., Ltd. |
|
Osaka-shi, Osaka 531-0077 (JP) |
|
| (72) |
Inventors: |
|
- Satoshi, Ikeda
Yamato-shi, Kanagawa 242-0021 (JP)
- Masayuki, Kamimura
Ichikawa-shi, Chiba 272-0025 (JP)
- Kazuo, Sonomura
Katsushika-ku, Tokyo 125-0041 (JP)
|
| (74) |
Representative: Hubert, Philippe et al |
|
Cabinet Beau de Loménie 158, rue de l'Université
75340 Paris Cédex 07
75340 Paris Cédex 07 (FR) |
|
| |
|
| (54) |
Method of pickling aluminium can bodies |
(57) This invention provides a method of pickling an aluminum can body comprising ejecting
a pickling agent from a tank against an aluminum can body caused to traverse said
tank overhead to clean them and recycling the used agent to said tank,
- wherein said pickling agent is an acidic aqueous solution containing (A) a polyethylene
glycol type detergent nonionic surfactant having an HLB value of 14 to 18 and (B)
a low-foaming nonionic surfactant having an HLB value of 2 to 12,
- the concentration of (A) is 100 to 5000 ppm and the ratio of (A) to (B) is 10:90 to
90:10, and
- the pickling agent in the tank is withdrawn out of the system from below the agent
level.