Patent ID: 6857734

Claim:
An inkjet printer having an inkjet print head through which a photo-curing type ink is ejected onto a print media in a printing process, comprising: a photo-irradiation device irradiating a beam of light to a target ink position on the print media onto which the photo-curing type ink has been ejected following the election of the photo-curing type ink through the inkjet print head; wherein the photo-curing type ink is an UV-curing type ink, and the photo-irradiation device is an ultraviolet irradiation device; the ultraviolet irradiation device comprises: an ultraviolet light generation section for generating the ultraviolet light; and one or more optical fibers through which the ultraviolet light generated by the ultraviolet light generation section is guided to a position close to the inkjet print head, the ultraviolet irradiation device irradiates the ultraviolet light onto the print media through the tips of the optical fibers; and the tips of the optical fibers are coupled in motion to the print speed of the inkjet print head and are set movably in a main scanning direction of the inkjet print head so that the ultraviolet light is irradiated onto the target ink position on the print media immediately following the ejection of the UV-curing type ink; and wherein when the inkjet print head is a serial scanning on-demand type head, a mean shifting speed H 1 of the tip of each optical fiber in the main scanning direction of the inkjet print head is given by the expression H 1 ≧W 1 ×V 1 /D, wherein W 1 is a print width in a sub scanning direction, V 1 is a relative speed between the inkjet print head and the print media in the main scanning direction, and D is an irradiation diameter of each optical fiber.