STEEL STRIP HAVING EXCELLENT PAINTING SHARPNESS AND PRESS MOLDABILITY AND METHOD FOR PRODUCING ROLLING DULL ROLL

摘要

This method is characterized by making a plurality of minute recesses in the surface of a steel plate by using a dull rolling roll on the surface of which projections consisting of Cr as a main component are provided uniformly, so as to improve definition of paint applied to the steel plate and the press formability thereof, each of these recesses having a diameter d of 50- 500 mu m and a depth of 2-40 mu m, these recesses having a total volume per 1 mm<2> of the steel plate of not less than 0.10 x 10<6> mu m<3>, a distance (P1) between the centers of recesses, which are adjacent to each other in the rolling direction, of 1.0d-4.0d and a distance (P2) between the center lines of adjacent rows of recesses, with respect to the rolling direction, of 1.0d-4.0d.