Patent GB-820694-A (GB)
Title: Method of and apparatus for transfer printing
IPC: B41L45/00
Filed: 1958-02-18
Abstract: 820,694. Addressing machines. ADDRESSOGRAPH - MULTI GRAPH CORPORATION. Feb. 18, 1958 [March 13, 1957], No. 5245/58. Class 100(2) In an addressing machine, a master strip comprising a thin porous material having a thermosoftening ink image on one surface thereof is moistened on the other surface, and passed to a printing station where it is pressed on, to a copy sheet by pressure members, one of which is heated, so that the ink is softened and a portion thereof is transferred to the copy sheet. The machine has a printing head 11 carrying a heated platen 12. above an impression plate 13, substantially as described in Specification 782,633. Copy sheets in the form of a web are fed over the plate 13, and a master strip 33 is fed at right angles to the copy sheets to overlie the latter, suitable guides 41, 42 for the strip being provided on, and at each side of, the platen 12. The master strip 33 is fed from a supply reel 53, over guide rollers 54, 55, a floating roller 56, a driven spindle 60, guide roller 61, through the printing station, over a guide roller 62, around another driven spindle 63, floating roller 64, and guide roller 65, and then to a rewind reel 66. A synchronized dualfeed arangement for the copy strip and master strip as described in Specification 703,336 may be uped. The master strip 33 comprises a paper or other thin porous carrier, and the thermo-softening ink image thereon may comprise a wax, such as carnauba wax, paraffin, or beeswax, and a non-drying liquid such as castor oil, mineral oil, or oleic acid. The platen temperature may be about 300‹F. The master strip is moistened on the non-image face by contact with a moistening pad 78, Fig. 1, to which water, ethyl alcohol, carbon tetrachloride, or other liquid in which the ink is insoluble, is fed from a reservoir 75, the pad and reservoir being supported by a bracket 76 between the roller 61 and the guide 41 on the platen 12. When the machine is at rest, release of tension causes the master strip 33 to sag to a portion, shown in dotted outline 33A, away from the moistening pad, thus. saturation of the strip is prevented. The liquid on the reverse face the master strip, is vaporized: by the heated platen during the printing operation. The modified moistening device shown in plan in Fig. 6, which is arranged on a bracket 102 in a position between the fixed and floating rollers 55, 56, includes a solenoid-operated means to move the moistening pad 106 positively away from the master strip 33 when the machine is inoperative. The pad, which is moistened by a reservoir of liquid 104, is carried by a support 107, pivoted on a bracket extension 108, and the other end 112 of the support is coupled by a link 116 to the armature 117 of a solenoid 110. The link 116 has catch abutments thereon adapted to co-operate with a cam 115, such that when the main switch of the machine is closed, the solenoid is energized temporarily to cause the moistening pad 106 to bear against the master strip 33, and when the main switch is opened to stop the machine the solenoid is again temporarily energized to cause the pad to move away from the master strip.