The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 1991
Filed:
Jun. 12, 1990
Charles W Spehrley, Jr, Hartford, VT (US);
Spectra, Inc., Hanover, NH (US);
Abstract
In the particular embodiments described in the specification, a hot melt ink jet system includes a temperature-controlled platen provided with a heater and with a thermoelectric cooler electrically connected to a heat pump, and a temperature control unit for controlling the operation of the heater and the heat pump to maintain a substrate on the platen which receives the ink at a temperature which provides a desired spot size without causing print-through. In certain embodiments, the substrate temperature is from about 20.degree. C. above to about 20.degree. C. below the melting point of the ink and is determined by subtracting half the difference between the jetting temperature and the temperature at which the ink has a viscosity of about 200-300 cp from the latter temperature. The apparatus also includes a second thermoelectric cooler to solidify hot melt ink in a selected zone more rapidly to avoid offset by a pinch roll coming in contact with the surface of the substrate to which hot melt ink has been applied. An airtight enclosure surrounding the platen is connected to a vacuum pump and has slits adjacent to the platen to hold the substrate in thermal contact with the platen.