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EP 1 546 417 A1

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(43) Date of publication: 29.06.2005 Bulletin 2005/26 (21) Application number: 03799144.5 (22) Date of filing: 26.09.2003

(51) International Patent Classification (IPC)7: C21D 8/10, C22C 38/28, C22C 38/50 (86) International application number: PCT/JP2003/012373 (87) International publication number: WO 2004/031420 (15.04.2004 Gazette 2004/16)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR Designated Extension States: AL LT LV MK (30) Priority: 01.10.2002 JP 2002288661 27.02.2003 JP 2003051427 (71) Applicant: SUMITOMO METAL INDUSTRIES, LTD. Osaka-shi,Osaka 541-0041 (JP)

(72) Inventors: Murao, Nobutoshi,Sumitomo Metal Industries, Ltd. Osaka-shi,Osaka 541-0041 (JP) Hisamune, N.,Sumitomo Metal Industries, Ltd. Osaka-shi,Osaka 541-0041 (JP) Osako, Hajime,Sumitomo Metal Industries, Ltd. Osaka-shi,Osaka 541-0041 (JP) Kondo, Kunio,Sumitomo Metal Industries, Ltd. Osaka-shi,Osaka 541-0041 (JP) (74) Representative: Nicholls, Michael John  J.A. KEMP & CO.,14, South Square,Gray's Inn London WC1R 5JJ London WC1R 5JJ (GB)