Patent ID: 8422922

Claim:
A tubular body comprising: a substrate including concave portions having one of a shape of a hemisphere, a cylinder, and an ellipse on a surface thereof; a surface layer formed on the surface of the concave portion-including side of the substrate, the surface layer having a thickness in a range of 5 μm to 400 μm; and a plurality of particles positioned at an interface between the substrate and the surface layer in each of the concave portions, wherein an average diameter of the concave portions is from about 0.01 μm to about 1,000 μm, a volume average particle diameter of the particles is from about 0.01 μm to about 15 μm, and the average diameter of the concave portions is from about 1 to about 10,000 times the volume average particle diameter of the particles, and a glass transition temperature of the surface layer is in a range of 100° C. to 200° C.