Image formation apparatus and image formation method

An image formation method performed by an image formation apparatus when executing a decorative medium printing program, the image formation method comprising:

• forming, by a non-lustrous image formation unit, a non-lustrous image of a non-lustrous developer on a first surface of a transparent medium;
• before or after the forming of the non-lustrous image, forming, by a lustrous image formation unit, a lustrous image of a lustrous developer comprising a metallic pigment including a first region and a second region on a second surface that is an opposite surface of the first surface of the transparent medium;
• and
• after forming one of the non-lustrous image and the lustrous image and before forming the other of the non-lustrous image and the lustrous image, flipping over the transparent medium by a reconveyance mechanism of the image formation apparatus, wherein
• in the forming of the lustrous image, a difference between a first adhesion ratio and a second adhesion ratio is 18.75% or more and 37.50% or less, where the first adhesion ratio is an amount of the lustrous developer adhered to the transparent medium per unit area in the first region, and the second adhesion ratio is an amount of the lustrous developer adhered to the transparent medium per unit area in the second region.

An image formation apparatus comprising:

• a storage storing a decorative medium printing program;
• a first image formation unit configured to form a first image of a non-lustrous developer;
• a second image formation unit configured to form a second image of a lustrous developer comprising a metallic pigment;
• a conveyance path that extends from a medium feeder to a discharge port through a transfer part at which the first image and the second image are transferred to a transparent medium which is a transparent medium;
• a reconveyance mechanism including a reconveyance path and configured to return the transparent medium from downstream to upstream of the transfer part with the transparent medium being flipped over;
• and
• a controller configured to control, based on printing data, the first image formation unit and the second image formation unit, and the reconveyance mechanism, wherein
• the decorative medium printing program controls, when executed by the controller, (i) the first image formation unit to form the first image on a first surface of the transparent medium, the reconveyance mechanism to return the transparent medium from downstream to upstream of the transfer part with the transparent medium being flipped over, and the second image formation unit to form the second image including a first region and a second region on a second surface of the transparent medium, which is an opposite surface of the first surface of the transparent medium, or (ii) the second image formation unit to form the second image including the first region and the second region on the second surface, the reconveyance mechanism to return the transparent medium from downstream to upstream of the transfer part with the transparent medium being flipped over, and the first image formation unit to form the first image on the first surface of the transparent medium, thereby obtaining the transparent medium that comprises the first image on the first surface and the second image on the first region and the second region of the second surface, such that a ratio of a second adhesion ratio to a first adhesion ratio is 62.50% or more and 81.25% or less, where the first adhesion ratio is an amount of the lustrous developer adhered to the transparent medium per unit area in the first region of the second surface, and the second adhesion ratio is an amount of the lustrous developer adhered to the transparent medium per unit area in the second region of the second surface.

An image formation method performed by an image formation apparatus by executing a decorative medium printing program, the image formation method comprising:

• forming, by a non-lustrous image formation unit, a non-lustrous image of a non-lustrous developer on a first surface of a transparent medium;
• before or after the forming of the non-lustrous image, forming, by a lustrous image formation unit, a lustrous image of a lustrous developer comprising a metallic pigment including a first region and a second region on a second surface that is an opposite surface of the first surface of the transparent medium;
• and
• after forming one of the non-lustrous image and the lustrous image and before forming the other of the non-lustrous image and the lustrous image, flipping over the transparent medium by a reconveyance mechanism of the image formation apparatus, wherein
• in the forming of the lustrous image, a rate of a second adhesion ratio to a first adhesion ratio is 62.50% or more and 81.25% or less, where the first adhesion ratio is an amount of the lustrous developer adhered to the transparent medium per unit area in the first region, and the second adhesion ratio is an amount of the lustrous developer adhered to the transparent medium per unit area in the second region.

An image formation apparatus comprising:

• a non-lustrous image formation unit configured to form a non-lustrous image and a correction image of a non-lustrous developer on a medium;
• a lustrous image formation unit configured to form a lustrous image of a lustrous developer on the medium;
• and
• a controller configured to control, based on printing data, the non-lustrous image formation unit and the lustrous image formation unit, wherein
• the controller is configured to control the non-lustrous image formation unit to form the correction image in a second region excluding a first region on a surface of the medium, and control the lustrous image formation unit to form the lustrous image including the first region and the second region superimposed on the correction image on the surface of the medium, and control the non-lustrous image formation unit to form the non-lustrous image superimposed on the lustrous image, such that a difference of a second adhesion ratio from a first adhesion ratio is set to 18.75% or more and 37.50% or less and an adhesion ratio of the correction image is set to a value same as the difference, where the first adhesion ratio is an amount of the lustrous developer adhered to the medium per unit area in the first region, and the second adhesion ratio is an amount of the lustrous developer adhered to the medium per unit area in the second region.