Patent ID: 7147730

Claim:
A method of producing a high carbon steel sheet, comprising the steps of: hot rolling a steel having chemical composition specified by JIS G 4051, JIS G 4401 or JIS G 4802, coiling the hot rolled steel sheet at 520 to 600° C., descaling the coiled steel sheet, annealing the descaled steel sheet at 640 to 690° C. for 20 hr or longer (primary annealing), cold rolling the annealed steel sheet at a reduction rate of 50% or more, and annealing the cold rolled steel sheet at 620 to 680° C. (secondary annealing), and wherein the temperature T 1 of the primary annealing and the temperature T 2 of the secondary annealing satisfy the following formula (1), 1024−0.6× T 1 ≦ T 2 ≦1202−0.80× T 1 . . . (1).