Image forming method

摘要

The method forms an image by directly depositing aqueous ink ejected from an inkjet recording apparatus (1) onto a recording medium (22). The method comprises: using, as the inkjet recording apparatus (1), an apparatus including: an image formation unit (14) having a line head type inkjet head (72C, 72M, 72Y, 72K) disposed opposite a circumferential surface of an image formation drum (70), the inkjet head (72C, 72M, 72Y, 72K) depositing the aqueous ink onto the recording medium (22) while the recording medium (22) is held and conveyed in rotation on the circumferential surface of the image formation drum (70); and a drying unit (16) arranged on a downstream side of the image formation unit (14), the drying unit (16) having a drying device (78, 80, 82) disposed opposite a circumferential surface of a drying drum (76), the drying device (78, 80, 82) drying a solvent in the aqueous ink deposited on the recording medium (22), the drying unit (16) drying the solvent by means of the drying device (78, 80, 82) while the recording medium (22) is held and conveyed in rotation on the circumferential surface of the drying drum (76); using, as the recording medium (22), a special paper which is a recording medium (22) successively laminated from a base paper (211), a first layer (212) containing a binder and a second layer (213) containing a white pigment, the base paper (211) with the first layer (212) provided thereon having a Cobb water absorbency of not higher than 5.0 g/m 2 with a contact time of 15 seconds based on a water absorbency test stipulated in JIS P8140, and the second layer (213) having a water absorption amount of not lower than 2 ml/m 2 and not higher than 8 ml/m 2 with a contact time of 0.5 seconds according to Bristow's method, and having a layer surface pH of not higher than 5.5 after pH adjustment; and using, as the aqueous ink, a special ink containing at least a resin dispersant (A), a pigment (B) that is dispersed by the resin dispersant (A), self-dispersible polymer micro-particles (C) and an aqueous liquid medium (D).