Image formation method and inkjet recording apparatus
An image formation method includes: applying a white ink onto an image formation area of a non-absorbent recording medium; performing image formation with a color ink on the image formation area of the non-absorbent recording medium; and drying the white ink and the color ink. The white ink contains a white pigment, a first aqueous medium, and first binder resin particles containing a first resin. The color ink contains a color pigment, a second aqueous medium, and second binder resin particles containing a second resin. Both the first binder resin particles and the second binder resin particles include identical resin particles. The first resin and the second resin each have a glass transition temperature of at least 40° C. and no greater than 80° C.
1 . An image formation method comprising:
applying a white ink onto an image formation area of a non-absorbent recording medium;
performing image formation with a color ink on the image formation area of the non-absorbent recording medium; and
drying the white ink and the color ink, wherein
the white ink contains a white pigment, a first aqueous medium, and first binder resin particles containing a first resin,
the color ink contains a color pigment, a second aqueous medium, and second binder resin particles containing a second resin,
both the first binder resin particles and the second binder resin particles include identical resin particles,
the first resin and the second resin each have a glass transition temperature of at least 40° C. and no greater than 80° C.,
the color ink has a surface tension ST C greater than a surface tension ST W of the white ink,
a difference between the surface tension ST C of the color ink and the surface tension ST W of the white ink is at least 0.5 mN/m and no greater than 10.0 mN/m,
a drying temperature in the drying is at least the glass transition temperature of each of the first resin and the second resin and no greater than 135° C.,
the drying time in the drying is at least 3 seconds and no greater than 125 seconds, and
the color ink and the white ink contain the same surfactant.
2 . The image formation method according to claim 1 , wherein
an interval from completion of the applying a white ink to completion of the performing image formation is no greater than 10 seconds.
3 . The image formation method according to claim 1 , wherein
the image formation method is used for front printing.
4 . The image formation method according to claim 1 , wherein
each of the first resin and the second resin is urethane resin.
5 . The image formation method according to claim 1 , wherein
in the applying a white ink, the white ink is applied onto the image formation area of the non-absorbent recording medium by ink jetting, and
in the performing image formation, the image formation is performed with the color ink on the image formation area of the non-absorbent recording medium by ink jetting.
6 . The image formation method according to claim 1 , wherein
the surface tension ST C of the color ink is at least 23.00 mN/m and no greater than 35.00 mN/m, and
the surface tension ST W of the white ink is at least 20.00 mN/m and no greater than 24.00 mN/m.
7 . An inkjet recording apparatus comprising:
a conveyance section that conveys a non-absorbent recording medium;
lineheads that perform image formation on the non-absorbent recording medium; and
a drying section that dries the non-absorbent recording medium after the image formation, wherein
the lineheads include:
a white ink head that ejects a white ink onto an image formation area of the non-absorbent recording medium; and
a recording head that is located downstream of the white ink head in terms of a conveyance direction of the non-absorbent recording medium and that performs the image formation with a color ink on the image formation area of the non-absorbent recording medium,
the white ink contains a white pigment, a first aqueous medium, and first binder resin particles containing a first resin,
the color ink contains a color pigment, a second aqueous medium, and second binder resin particles containing a second resin,
both the first binder resin particles and the second binder resin particles include identical resin particles,
the first resin and the second resin each have a glass transition temperature of at least 40° C. and no greater than 80° C.,
the color ink has a surface tension ST C greater than a surface tension ST W of the white ink,
a difference between the surface tension ST C of the color ink and the surface tension ST W of the white ink is at least 0.5 mN/m and no greater than 10.0 mN/m,
a drying temperature in the drying section is at least the glass transition temperature of each of the first resin and the second resin and no greater than 135° C.,
a drying time in the drying section is at least 3 seconds and no greater than 125 seconds, and
the color ink and the white ink contain the same surfactant.