Printing apparatus, printing method, printing control method, and computer program
A printing head configured to apply white light-blocking ink, specialty gloss ink, and color ink is controlled, and the inks are applied so that the color ink, the specialty gloss ink, and the white light-blocking ink are formed in this order onto a printing medium having light-transmissive properties. When the printing medium is viewed from the surface on which ink has not been formed, a white ink layer is formed behind the color ink layer and the metallic ink layer, and light-blocking properties can be ensured. Because the amount of the metallic ink can be reduced, adequate expression of the color ink can be ensured.
1. A printing apparatus for printing using a plurality of inks, the printing apparatus comprising:
a printing head configured to apply the inks including at least a light-blocking ink, a specialty gloss ink, and a color ink as the inks; and
a control unit configured to control the printing head in at least one of a first mode and a second mode,
the first mode being for applying the inks onto a printing medium having light-diffusing properties in the order of the light-blocking ink, the specialty gloss ink over the light-blocking ink, and the color ink over the specialty gloss ink,
the second mode being for applying the inks onto a printing medium having light-transmissive properties in the order of the color ink, the specialty gloss ink over the color ink, and the light-blocking ink over the specialty gloss ink.
2. The printing apparatus according to claim 1 , wherein
the control unit is configured to apply the specialty gloss ink onto the printing medium at a predetermined percentage set as an upper limit.
3. The printing apparatus according to claim 1 , wherein
the specialty gloss ink is a texture-expressing ink including a pigment expressing a predetermined texture.
4. The printing apparatus according to claim 3 , wherein
optical characteristics of the specialty gloss ink printed on a surface of the printing medium are dependent on an angle of reflection.
5. The printing apparatus according to claim 3 , wherein
the specialty gloss ink is a metallic ink including a pigment expressing a metallic finish.
6. The printing apparatus according to claim 1 , further comprising
a main scanning unit configured to move the printing head in a width direction of the printing medium, wherein
the printing head includes a plurality of nozzles aligned in a direction intersecting a movement direction of the printing head for each of the inks to discharge the inks,
the nozzles is arranged in the order of the nozzles for the light-blocking ink, the nozzles for the specialty gloss ink, and the nozzles for the color ink from an upstream position in the movement direction of the printing head.
7. The printing apparatus according to claim 1 , wherein
in the second mode, the control unit is configured to apply a fixed amount of at least one of the light-blocking ink and the specialty gloss ink in a predetermined region including a region for applying the color ink regardless of an image to be printed.
8. The printing apparatus according to claim 1 , wherein
the printing medium having light-diffusing properties for the second mode is of a color whose brightness is lower than a print density realizable by black ink or the color ink, and
in the first mode, the control unit is configured to apply the light-blocking ink onto the printing medium having light-diffusing properties so that a value of a brightness index L* for a region in which the light-blocking ink has been applied is 70 or higher.
9. A printing method using a plurality of inks, the printing method comprising:
selecting a mode from a plurality of modes including a first mode and a second mode;
applying the inks onto a printing medium having light-diffusing properties in the order of color ink, specialty gloss ink over the color ink, and light-blocking ink over the specialty gloss ink in the first mode; and
applying the inks onto the printing medium in the order of light-blocking ink, specialty gloss ink over the light-blocking ink, and color ink over the specialty gloss ink in the second mode.