STEEL SHEET FOR ULTRA-THIN TWO-PIECE CANS HAVING EXCELLENT ANTI-WRINKLING PROPERTIES AND METHOD FOR PRODUCING THEREOF

The present invention provides a steel sheet for a two-piece can characterized in that the equation, (N existing as AlN)/(N content)>0.5, is satisfied, the average diameter of AlN is in the range of 0.01 to 0.10 mu m, the ratio of the number of AlN with a diameter of 0.01 mu m or less to the number of AlN with a diameter of at least 0.005 mu m is 10% or less, the average diameter of MnS is in the range of 0.03 to 0.40 mu m, and the ratio of the number of MnS with a diameter of 0.03 mu m or less to the number of MnS with a diameter of at least 0.005 mu m is 50% or less. Further, by specifying chemical composition, slab reheating temperature and coiling temperature in hot rolling, and re-cold-rolling reduction ratio after annealing, a high yield of steel sheet and good can formability can be achieved, the wrinkle generation rate during neck diameter reduction after drawing, ironing and stretching can be reduced and, further, good properties can be obtained even processed at a low annealing temperature. Thus the production of a highly efficient steel sheet for a two-piece can capable of averting heat-buckle is made possible. Further, buckling generation at an annealing process, earing generation during cup forming and wrinkle generation during the diameter reduction of a can body opening can be avoided. And thus a steel sheet for a two-piece can with a thickness of 0.19mm or less can be provided.