Coating processes – Transfer or copy sheet making
Patent
1987-02-03
1989-04-11
Robinson, Ellis P.
Coating processes
Transfer or copy sheet making
428195, 428207, 428484, 4284881., 428913, 428914, B41M 312
Patent
active
048205516
DESCRIPTION:
BRIEF SUMMARY
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a National Phase application of PCT/EP 86/00 335 filed June 4, 1986 and based, in turn, upon German National application PE 35 20 308.0 filed 7 June 1985 under the International Convention.
FIELD OF THE INVENTION
The invention concerns a thermocolor ribbon for thermal-transfer printing and a process for the production of this ribbon, the ribbon comprising a layer of a melt-applied color on one side of a plastic foil as carrier, where the melt-applied color contains a wax or a waxlike substance, a coloring agent and an organic binding agent.
BACKGROUND OF THE INVENTION
Thermocolor ribbons usually comprise a foil-like carrier which may, for instance, consist of paper or plastic, and a layer of a melt-applied color, particularly in the form of a layer of coloring agent or carbon black bound to wax. In these thermocolor ribbons, the melt-applied color is melted by means of a thermal printing head, and transferred to a recording paper. In this instance, one speaks generally of a TCR ribbon ("Thermal Carbon Ribbon"). Thermal printers which impress a thermal character during the printing process are known, e.g. from DE-OS 2 062 494 and 2 406 613 as well as from DE-OS 3 224 445. During the printing process, the procedure is, in detail, as follows: the print head of a thermal printer presses the thermocolor ribbon against the recording paper, thereby causing the print head to develop temperatures which may maximally lie at about 400.degree. C. The uncoated backside of the thermocolor ribbon or the foil-like carrier is, during the printing operation, in direct contact with the print head or the thermal symbol formed thereon. At the instant of the printing operation proper, the relative speed between the thermocolor ribbon and the printing paper is zero. The melt-applied color is transferred from the thermocolor ribbon to the printing paper through a melting process in the shape of the character to be imprinted. Upon disengagement of the thermocolor ribbon, the melted symbol remains attached to the printing paper and solidifies.
In addition to the thermocolor ribbons described above, with simple foil-like carriers, there are also thermocolor ribbons where the thermal symbol is created not by a thermal print head, but by the resistive heating of a specially designed foil-like carrier. The melt-applied color, which is the "operative layer" during the printing process, also contains the materials enumerated above. Within the art, the foregoing is called an "ETR" thermocolor ribbon ("Electro Thermal Ribbon"). A thermotransfer-printing system of this type is described in U.S. Pat. No. 4,309,117.
Thermocolor ribbons are already known which print several times (i.e. they are designed for multi-use). Such thermocolor ribbons are described, for instance, in EP-A 0 063 000. In accordance therewith, the melt-applied color of the thermocolor ribbon is of particulate material, which is insoluble in the solvent of the coating liquid and does not melt below 100.degree. C., and further incorporates a particulate material with a melting point between 40.degree. and 100.degree. C. The particulate material not melting below 100.degree. C. should preferably be a metal oxide, a metal, organic resin or carbon black. The layer os the melt-applied color which represents a solid mixture shall, by means of said special particulate material, receive a heterogeneous structure, which allows only a small quantity of the molten material to be transferred to be used-up during a single printing operation.
In connection with the known thermocolor ribbons, it has become evident that improvements are needed in their printouts.
SUMMARY OF THE INVENTION
It is, therefore, the object of the invention to further develop the process described initially, so that a thermocolor ribbon becomes available which produces particularly sharp imprints.
SUMMARY OF THE INVENTION
In accordance with the invention, the object is attained in that a coating liquid which contains a thermoplastic bonding
REFERENCES:
patent: 2872340 (1959-02-01), Newman et al.
patent: 3287153 (1966-11-01), Schwarz et al.
patent: 3935362 (1976-01-01), Tat-Hin Sund et al.
patent: 4296150 (1981-10-01), Mecke et al.
patent: 4309117 (1982-01-01), Chang et al.
patent: 4592945 (1986-06-01), Mecke et al.
patent: 4661393 (1987-04-01), Uchiyama et al.
patent: 4675063 (1987-06-01), Mecke et al.
IBM Technical Disclosure Bulletin, vol. 27, No. 3, Aug. 1984.
Krauter Heinrich
Kuchenreuther Wieland
Mecke Norbert
Schmedes Albert
Dubno Herbert
Pelikan Akteingesellschaft
Robinson Ellis P.
Ryan P. J.
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