Cassette for heat transfer sheet

Abstract: A cassette for heat transfer sheet, wherein a dislay means for displaying information concerning the number of recordable picture surfaces is provided on the outer surface of the cassette case of the cassette for heat transfer or on the heat transfer sheet housed within the cassette.

Description: This invention relates to to a cassette for heat transfer sheet. US-A-4496955 discloses a cassette in which a web of thermally transferable material is bi-directionally movable between a supply reel and a take up reel housed in the cassette. JP-A-59 196 283 discloses a cassette housing an ink ribbon wherein a core body is stuck to the leading end of the ink ribbon by a single surface sticky tape. EP-A-75672 discloses a ribbon structure of a typewriter wherein the leader and trailer are formed by adhering over the inked side of the ribbon a thin adhesive faced tape or foil, and wherein the tape or foil is provided with a region of adhesive engagement for attachment to supply and take-up spools. Cassette for heat transfer sheet The heat transfer sheet can be used generally in a state of its being wound around bobbins, but it becomes important in operation to house such heat transfer sheet so that it can be mounted on and dismounted from a printer in a simple manner. The cassette of the present invention for this purpose is adapted to house a delivery roll for the heat transfer sheet and a take-up roll and is formed from a plastic containing a lubricant. For example, by the use of a cassette in which at least one of the cassette body and lid which are plastic molded products and the bobbins comprises a plastic containing a lubricant, generation of dust can be prevented, whereby white dropout of the printed image formed by a printer can be prevented as much as possible to contribute to formation of a clear image. The delivery roll and the take-up roll of the heat transfer sheet wound on the bobbins is subjected to moisture barrier packaging after or before assembled in a cassette. Also, if necessary, a cushioning material may be employed. After such moisture barrier packaging, the package may be placed in a box by itself or together with a packaged image-receiving sheet (moisture barrier packaged, if necessary). The cassette used generally has a sectional shape of spectacles or otherwise of the letter S. When a cassette as described above is not used, the delivery roll and the take-up roll are packaged for moistureproofness with the use of a cushioning material and mounted on a heat-sensitive printer. When the heat transfer sheet is wound on a delivery roll, the terminal end is first fixed by adhesion to the winding core of the delivery roll by a double adhesive coated tape as set out in the appended claim. As the method for adhesion fixing, although both surfaces can be caused to adhere firmly with a strong adhesive tape so that the heat transfer sheet will not peel off from the winding core, in this case, during usage, the terminal end can be detected by detecting the variation of the torque imposed on the heat transfer sheet from the prescribed torque during ordinary operation at the time when transfer of the prescribed number of sheets has been completed. Also, in addition to the above case, when adhesion fixing is carried out at the terminal end of the heat transfer sheet with the use of the double-coated tacky tape with different adhesive forces on the surfaces, namely, a double-coated tacky tape with greater adhesive force between the heat transfer sheet and the tacky tape than the adhesive force between the winding core and the tacky tape, since the heat transfer sheet is completely wound on the wind-up roll at the time when use of the heat transfer sheet is completed, the terminal end can be determined by detecting a variation in the torque at that time. The heat transfer sheet is fixed on the wind core so that the terminal end of the heat transfer sheet will be wound up by insertion thereof into a cutout formed in the longitudinal direction of the winding core. In mounting the roll, the cassette body can be divided into the two portions of an upper part and a lower part to make mounting of the roll of the heat transfer sheet in the cassette easier. In this case, after mounting respectively the delivery roll and the wind-up roll, the upper and lower cassette body can be integrated by sealing according to a method such as ultrasonic sealing. Also, when the delivery roll is mounted in the cassette, for prevention of jolting of the bobbin, the core of the bobbin may be supported with a mechanism such as a spring. Further, it is preferable to prevent the roll from reverse rotation by fitting a concave portion of the bobbin end and a concave portion of the cassette case simultaneously with placing a rubber against the portion. Further, the external surface of the above cassette case or the heat transfer sheet itself housed in the cassette is also provided with a display means for displaying information concerning the recordable number of picture faces and others. As for other items of information, they may be classified into the kinds of heat transfer sheets, for example, for Standard, for OHP, for Monochromatic, etc. The printing conditions can be altered by having these information items recognized by a printer. The above information items may be displayed by the label of a bar code (either optical or magnetic), letters or color labels. Alternatively, they can be displayed by the color of the cassette. Alternatively, it is possible to practice such a method as sticking of a color label or sticking of a reflection plate, applying marks, letters or magnetic patterns of a bar code, etc. directly or indirectly, by provision thereof on a separate sheet. Or, the method in which holes are opened or projections are provided on the cassette may also be employed. Similarly, various information items may be also displayed in the heat transferable sheet or the cassette housing the sheet therein. Information in this case may include front and back, head and tail, size, kind, etc. Alternatively, in the cassettes , there may be also provided a hidden mark evidencing its genuineness, including printing with an ink discriminable by UV-ray irradiation, provision of an interference pattern, provision of a mark of drop-out color, etc.

Claims: A cassette for heat transfer sheet comprising: a cassette case having a display means on the outer surface thereof; a delivery roll and a take-up roll of a heat transfer sheet, said delivery and take-up rolls being capable of housing in said cassette case, said cassette being formed at least partially of a plastic containing a lubricant; said delivery roll having a winding core, and the terminal end of said heat transfer sheet being secured by adhesion to the winding core of said delivery roll by a double-coated tacky tape in such a manner that the adhesive force between said heat transfer sheet and said tacky tape is greater than that between said winding core and said tacky tape.

Inventors: AKADA MASANORI, KAMAKARI KATSUHIRO, KANTO JUMPEI, KITA TATSUYA, KUTSUKAKE MASAKI, NAKAMURA MASAYUKI, NISHITANI NOBUHISA, SAITO HITOSHI, AKADA, MASANORI, KAMAKARI, KATSUHIRO, KANTO, JUMPEI, KITA, TATSUYA, KUTSUKAKE, MASAKI, NAKAMURA, MASAYUKI, NISHITANI, NOBUHISA, SAITO, HITOSHI, Kamakari, Katsuhiro, 102, Daikoku Mansion, 5-10,
Applicants: DAINIPPON PRINTING CO LTD, DAI NIPPON INSATSU KABUSHIKI KAISHA
Application year: 1988
Main classification: B41J17
IPC codes: B41M5, B41J17