Patent ID: 6377291
Filing Date: 2002-04-23
Classification: B41J

Abstract:
An image forming apparatus which uses a thermal transfer ribbon having a plurality of ink layers of different colors containing a coloring material selected from the group consisting of a pigment and dye, and a long, film-like intermediate transfer medium capable of transferring said ink layers from said thermal transfer ribbon, comprising:a platen for holding said intermediate transfer medium when said ink layers are transferred from said thermal transfer ribbon to said intermediate transfer medium; a driving mechanism which comprises a driving source and transmission members and drives said platen, said transmission members being interposed between said driving source and said platen to mesh with each other and having a speed reducing ratio which is an integer multiple; a thermal head which has a substantially regular polygonal or substantially circular heat-generating portion and selectively heats said thermal transfer ribbon while said intermediate transfer medium and said thermal transfer ribbon are overlapped on said platen, thereby selectively transferring said ink layers onto said intermediate transfer medium; control means for forming a record image containing an area gradation image on said intermediate transfer medium by driving said thermal head, on the basis of image information, in collaboration with driving of said platen by said driving mechanism, said area gradation image being made up of sets of dots having different colors formed by said ink layers and having a color set by stacking said dots having different colors in substantially the same spot; and heating and pressing means for overlapping said intermediate transfer medium on which said record image is formed and a target body and applying heat and pressure to said intermediate transfer medium and said target body, thereby transferring said record image from said intermediate transfer medium onto said target body.