Image forming apparatus and method of controlling same

An image forming apparatus comprising:

• a printhead configured to add energy to an image material including a plurality of color development layers that have different color development characteristics and develop colors in response to heat;
• a control unit configured to output, based on image data, a signal pattern used to control the energy to be added to the image material by the printhead;
• a detection unit configured to detect a temperature of the image material;
• and
• a setting unit configured to set a predetermined threshold based on the image data,
• wherein the control unit causes the image formation by the printhead to wait in a case in which it is determined that the temperature detected by the detection unit exceeds the predetermined threshold.

An image forming apparatus comprising:

• a printhead configured to add energy to an image material including a plurality of color development layers that have different color development characteristics and develop colors in response to heat, the plurality of color development layers including a first color development layer and a second color development layer that are formed by layering the first color development layer and the second development layer in that order as viewed from a side of the printhead;
• a detection unit configured to detect a temperature of the image material;
• a setting unit configured to set a predetermined threshold based on the image data;
• and
• a control unit configured to output, based on image data, signal patterns for controlling the energy to be added to the image material by the printhead, the signal patterns including (i) signal patterns for developing respective color development layers of the plurality of color development layers and (ii) a signal pattern for developing colors reproduced by developing color development layers that are not colors reproduced by developing all of the color development layers, the control unit causing the image formation by the printhead to wait in a case in which it is determined that the temperature detected by the detection unit exceeds the predetermined threshold,
• wherein the setting unit sets the predetermined threshold based on a frequency of a signal pattern used to develop a color designated in the image data.