Printing apparatus and print control method

A printing apparatus configured to heat a sheet-shaped print medium in which a plurality of color development layers that develop colors in accordance with heating are stacked in correspondence with a plurality of colors so as to form an image on the print medium by causing a desired color development layer in the plurality of color development layers to independently develop the color, the apparatus comprising:

• a printhead including a plurality of heating elements;
• a drive unit configured to drive each of the plurality of heating elements of the printhead using a first pulse for preheating a predetermined color development layer, and a second pulse applied after the first pulse to cause the predetermined color development layer to develop the color;
• and
• a pulse control unit configured to, when developing a specific color, perform a control in which a pulse width of the first pulse is increased and/or a control in which the number of times of application of the second pulse is increased such that another color development layer that is not used to reproduce the specific color does not develop the color,
• wherein the pulse control unit performs a control in which an application timing of the first pulse for preheating the color development layer to be caused to develop the color matches at least an application timing of the second pulse used for color development of another color development layer different from the color development layer.

A printing apparatus configured to heat a sheet-shaped print medium in which a plurality of color development layers that develop colors in accordance with heating are stacked in correspondence with a plurality of colors so as to form an image on the print medium by causing a desired color development layer of the plurality of color development layers to develop the color, comprising:

• a printhead including a plurality of heating elements;
• a drive unit configured to drive each of the plurality of heating elements of the printhead using a first pulse for preheating a predetermined color development layer, and a second pulse applied after the first pulse to cause the predetermined color development layer to develop the color;
• a conveyance unit configured to convey the print medium in a first direction with respect to the printhead;
• and
• a control unit configured to perform a control in which the drive unit uses the first pulse in a first pixel that is located in an image non-forming region of the print medium, and the drive unit uses the second pulse in a second pixel that is located in an image forming region of the print medium and is to be printed after the first pixel,
• wherein in a case where the color development layer to be caused to develop the color at a position of the second pixel is a first color development layer and in a case where the color development layer to be caused to develop the color is a second color development layer different from the first color development layer, the control unit performs, based on image data, changing a duty ratio of the first pulse used at a position of the first pixel and/or changing an application time of the first pulse.

A print control method of a printing apparatus configured to heat, by a printhead including a plurality of heating elements, a sheet-shaped print medium in which a plurality of color development layers that develop colors in accordance with heating are stacked in correspondence with a plurality of colors so as to form an image on the print medium by causing a desired color development layer of the plurality of color development layers to develop the color, comprising:

• when driving each of the plurality of heating elements of the printhead using a first pulse for preheating a predetermined color development layer, and a second pulse applied after the first pulse to cause the predetermined color development layer to develop the color,
• performing a control in which the first pulse is used in a first pixel that is located in an image non-forming region of the print medium, and the second pulse is used in a second pixel that is located in an image forming region of the print medium and is to be printed after the first pixel;
• and
• performing, based on input image data, changing a duty ratio of the first pulse used at a position of the first pixel and/or changing an application time of the first pulse in a case where the color development layer to be caused to develop the color at a position of the second pixel is a first color development layer and in a case where the color development layer to be caused to develop the color is a second color development layer different from the first color development layer.