Printing method on curved surface and curved surface body printed by that method

A method for printing on a curved surface, comprising the steps of:

• applying printing ink to a protrusion portion of a relief printing master plate which is a flat plate with the protrusion portion 0.1-15 μm high in height h;
• pressing a rubber or rubbery roll-like elastic blanket, which has a curved surface with a predetermined shape set correspondingly to a curved surface of a to-be-printed curved surface body, onto the relief printing master plate disposed in a fixed position and supplied with the printing ink, so as to transfer the printing ink to the curved surface with the predetermined shape;
• and
• moving the roll-like elastic blanket having the curved surface with the predetermined shape having the printing ink transferred thereto, and
• bringing the roll-like elastic blanket into contact with the curved surface of the to-be-printed curved surface body so as to perform printing thereon, wherein
• a radial thickness T of the roll-like elastic blanket has at least a relation of 2H≦T≦8H to a level difference H among irregularities of the curved surface of the to-be-printed curved surface body,
• a material of the roll-like elastic blanket is silicone rubber, and hardness (JIS A-scale) thereof is 3-20,
• surface roughness of the roll-like elastic blanket is 0.5-2 μm in Hmax, and
• the printing ink is a UV ink having a viscosity of 5-250 PaS (at 25° C.).