A printer includes a thermal head including a plurality of heat generating elements configured to apply energy to a recording medium, and a controller configured to perform control of periodically supplying the power to the plurality of heat generating elements. The recording medium includes a first color developing portion configured to develop a first color and a second color developing portion configured to develop a second color. The controller is configured to periodically supply the power to the plurality of heat generating elements, set an average cycle for supplying the power to a first average cycle, in a case of causing the first color developing portion to develop the first color, and set an average cycle for supplying the power to a second average cycle longer than the first average cycle, in a case of causing the second color developing portion to develop the second color.

A printer driven by power of a battery, the printer including a thermal head including a plurality of heating elements arranged along a direction perpendicular to a conveying direction, a drive unit to supply power to the thermal head to drive the thermal head, and a processor to control driving and perform printing on the recording medium according to printing data, in which the processor calculates, based on a state of its own printer, a printing cycle related to printing of each line for the line configuring the printing data and an energization time for supplying power to the thermal head within the printing cycle, adjusts the energization time according to a characteristic difference between an internal resistance of the reference battery and an internal resistance of the battery, and prints for one line by supplying power to the drive unit during the energization time after adjustment.

A printing apparatus operates by receiving power from a USB PD adapter outputting a DC voltage. The printing apparatus includes a first printing section configured to perform printing on a medium, a second printing section configured to perform printing on the medium, and a negotiation information obtainer configured to obtain negotiation information between the printing apparatus and the USB PD adapter. The negotiation information includes a rated power value. When the rated power value is less than the first predetermined value, the second printing section is configured to not perform printing on the medium during a time period in which the first printing section performs printing on the medium, and the first printing section is configured to not perform printing on the medium during a time period in which the second printing section performs printing on the medium.

Provided is a portable thermal printing device including: a support plate assembly; a heat insulation plate disposed on the support plate assembly; and a heating plate disposed on the heat insulation plate and including a uniform heating plate body, a covering layer, and a heating element disposed between the uniform heating plate body and the covering layer; and an electrical connection element detachably connected to the heating element via magnetic attraction and configured to connect to an external power source and supply power to the heating element. With such a simple structure, portable thermal printing operations can be achieved.