Thermal transfer printing method and thermal head used in method thereof.

摘要

A thermal transfer printing method uses an ink sheet (12) having solid ink layers (11) whose optical reflection density is smaller than a maximum value of the optical reflection density of picture elements to be printed, and comprises the first step of printing the picture elements by moving a plain paper (4) and the ink sheet (12) in a forward direction (FW) so that the solid inkl layers are transferred onto the plain paper (4), the second step of moving the plain paper (4) in a backward direction (BW) and the third step of transferring the solid ink layers (11) in an overlapping manner onto the picture elements printed in the first step, by moving the plain paper (4) and the ink sheet (12) again in the forward direction (FW). In the first and third steps, the solid ink layers (11) are completely transferred onto the plain paper (4). The gradation of the picture elements is determined by the number of transfer times. Therefore, each picture element in the gradation can be printed in an extremely stable manner with good reproducibility.