Thermal transfer printer that is capable of maintaining intermediate transfer sheet tension constant

An intermediate transfer type thermal transfer line printer in which ink of a multi-color ink sheet is transferred on an intermediate sheet using a line thermal head to form a primary image, and the primary image is retransferred on a transfer medium using a retransfer mechanism to thereby form a full-color image on the transfer medium, wherein

• the thermal transfer line printer is provided with a tension roller disposed to face to a moving path of the intermediate transfer sheet, a rotatable tension roller support frame that supports the tension roller rotatably and presses the tension roller against the intermediate transfer sheet, a tension roller position detection mechanism that detects a position of the tension roller, and a controller that controls operation of an intermediate transfer sheet feeding motor that feeds at least the intermediate transfer sheet,
• wherein the tension roller position detection mechanism is provided with a detector disposed on the tension roller support frame and a sensor that detects the position of the detector, and
• wherein the controller, when feeding the intermediate transfer sheet, controls the intermediate transfer sheet feeding motor so as to maintain the detector in a detection range of the sensor.