| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cold-rolled steel sheet having an excellent mold-galling property even if used as a hard-to-mold material such as a high-strength steel sheet the surface pressure of which is increased when press-molded. <P>SOLUTION: The surface of the cold-rolled steel sheet has an organic/inorganic composite film containing an organic resin and a crystalline layered substance. The organic/inorganic composite film has a 0.10-2.0 μm average thickness and contains a ≥0.5 parts weight solid content of the crystalline layered substance based on a 100 parts weight solid content of the organic resin. The crystalline layered substance is, for example, a layered double hydroxide shown by [M<SP POS="POST">2+</SP><SB POS="POST">1-X</SB>M<SP POS="POST">3+</SP><SB POS="POST">X</SB>(OH)<SB POS="POST">2</SB>][A<SP POS="POST">n-</SP>]<SB POS="POST">x/n</SB>-zH<SB POS="POST">2</SB>O (where M<SP POS="POST">2+</SP>is preferably one or two or more of Mg<SP POS="POST">2+</SP>, Ca<SP POS="POST">2+</SP>, Fe<SP POS="POST">2+</SP>, Ni<SP POS="POST">2+</SP>and Zn<SP POS="POST">2+</SP>; M<SP POS="POST">3+</SP>is preferably one or two or more of Al<SP POS="POST">3+</SP>, Fe<SP POS="POST">3+</SP>and Cr<SP POS="POST">3+</SP>; A<SP POS="POST">n-</SP>is preferably one or two or more of OH<SP POS="POST">-</SP>, CO<SB POS="POST">3</SB><SP POS="POST">2-</SP>, Cl<SP POS="POST">-</SP>and (SO<SB POS="POST">4</SB>)<SP POS="POST">2-</SP>). <P>COPYRIGHT: (C)2012,JPO&INPIT |
