TUBULAR BODY

摘要

PROBLEM TO BE SOLVED: To provide a tubular body, in which the increase of the weight due to the film, which aims for coloration, is very small and the high brightness coloring is favorably recognized visually by a method wherein a thin interference film having the specified value of thickness is formed by the physical metallization of a thin film material on the outer surface of a coating film formed on the outer surface of a tube stock, which is produced by winding a sheet-like prepreg around a core material and then firing the prepreg. SOLUTION: A tube stock 1 is formed into a tube by winding a sheet-like prepreg around a core material and further winding a forming tape spirally on the prepreg and then firing and finally removing the forming tape. Then, a coating film 2 is formed on the outer surface of the tube stock 1. Further, the outer surface S of the coating film 2 is finished smoothly. Furthermore, with a thin film material by means of a vacuum metallizing means as physical metallization, a thin interference film having the thickness of 7,000Åor less is formed on the surface of the coating film 2 of the tube stock 1. Due to the thin interference film A, the light R1 reflected at the surface of the thin interference film A and the light R2 reflected at the boundary surface (or the outer surface S of the coating film) on the tubular body side of the thin interference film A interfere with each other, resulting in vanishing a specified wavelength corresponding to the film thickness (d) at that region and the refractive index of the thin interference film A so as to form color and, at the same time, obtaining the coloring having the hue in a visible range.