Patent ID: 8454154

Claim:
An ink jet recording device comprising: a recording head configured to eject ink droplets onto a recording medium; a conveying member configured to convey the recording medium in a conveying direction, the recording medium having a leading edge and a trailing edge in the conveying direction; a platen disposed in confrontation with the recording head to support the recording medium while keeping a predetermined distance from the recording head; a supporting member disposed in the platen to slide in the conveying direction while supporting the recording medium; and a driving member configured to drive the supporting member to start sliding in the conveying direction at a starting timing corresponding to a position of at least one of the leading edge and the trailing edge, wherein the supporting member has a length (R) in the conveying direction, and the length (R) satisfies the equation R=H−(E 1 +E 2 ), in which: H: a length of a maximum printing region of the recording head in the conveying direction; E 1 : p 1 +f; E 2 : p 2 +f; p 1 : a length by which the recording medium overhangs the supporting member in the conveying direction when a borderless recording is performed for a leading edge area of the recording medium; p 2 : a length by which the recording medium overhangs the supporting member in a direction opposite to the conveying direction when a borderless recording is performed for a trailing edge area of the recording medium; and f: a length by which an ejecting region of the recording head that actually ejects ink droplets overhangs the recording medium in the conveying direction when the borderless recording is performed for the leading edge area of the recording medium and in a direction opposite to the conveying direction when the borderless recording is performed for the trailing edge area of the recording medium.