To reduce a printing unevenness of a thin film by providing a printing protrusion on a letterpress arranged on an outer periphery of a cylindrical printing roller, and providing a dummy printing protrusion to be brought into pressure contact with a printing surface before the protrusion, thereby alleviating an impact in the case of bringing the protrusion into contact with the printing surface.

On a letterpress 7, a printing protrusion 71 having a pattern shape to be formed and a dummy printing protrusion 72 for alleviating an impact in the case of bringing the protrusion 71 into pressure contact with a material to be printed by bringing the protrusion 72 into pressure contact with the material before the protrusion 71 is brought into pressure contact with the material. The protrusion 72 is, for example, provided at the letterpress 7 so as to be brought into pressure contact with a position out of a thin film printing range of a printing surface to be cut out after the thin film printing. Accordingly, even if a film thick distribution occurs at this position according to its impact, no influence is affected. Thus, the thin film having small printing unevenness can be printed, and a glass board having a uniform and good thin film can be formed.