Abstract: A transfer ink film having one major surface containing sublimable dyes is passed through a path between the surface of a drum and a thermal head having a plurality of heating elements which are selectively energized in response to input image signal, while a record sheet is fed from a record-sheet feed part of a printing apparatus to said path so as to be superposed on the transfer ink film. As a result, the dyes are transferred by sublimation from the transfer ink film to the superposed record sheet. During the feed of the record sheet, any dust particles or the like attached to the surface of the sheet are removed by an adhesive roller, an electric discharge brush and so on whereby a high-quality image can be obtained on the record sheet. The record sheets are contained in the form of a stack in a sealed cassette which is detachably inserted into the record-sheet feed part of the printing apparatus.