TWO-PIECE SEAMLESS ALUMINUM CONTAINER, AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To provide a light-colored, low-saturation two-piece seamless Al container by specifying the lightness, chromaticity, and saturation of an outer surface of the container which is obtained by drawing and ironing an Al sheet covered with synthetic resin thereby improving adhesion of the resin film to Al. SOLUTION: A two-piece seamless Al container is obtained by drawing and ironing an Al sheet covered with a synthetic resin film. The inequalities of L*>60, and c*=(a*<2> +b*<2> )<1/2> <5 are satisfeid, where L* is the lightness, a* and b* are B* are chromaticity when the outer surface of the container is expressed in terms of the chromaticity of L*a*b* color specification system, and c* is the saturation obtained from the chromaticity a* and b*. Concerning an inner surface of the container, the surface roughness Ra (B) of a bottom part satisfies the inequality of Ra<=0.5μm, the surface roughness Ra(W) of a body wall part and the surface roughness Ra(F) of an upper body part satisfy the inequality Ra(W)=(Rz/ Ra)(B) is preferably satisfied between a bottom part B and upper part F.