| Thermal Printer |
Article Index for Thermal |
Website Links For Thermal |
Information AboutThermal Printer |
| CATEGORIES ABOUT THERMAL PRINTER | |
| computer printers | |
| non-impact printers | |
| thermochromism | |
|
See Also: Thermal transfer printer A thermal printer (or '''direct thermal printer''') produces a printed image by selectively heating coated Thermochromic Paper when the paper passes over the thermal Print Head . The coating turns Black in the areas where it is heated, producing an image. Two-color direct thermal printers are capable of printing both black and an additional Color (often Red ), by applying Heat at two different Temperature s. Thermal Transfer Printing is a related method that uses a heat-sensitive ribbon instead of heat-sensitive paper. ESSENTIAL MECHANISMS A thermal printer comprises these key components:
In order to print, one inserts thermo-sensitive paper between the thermal head and the platen. The printer sends an Electrical Current to the Heating Resistor of the thermal head, which in turn generates heat in a prescribed pattern. The heat activates the thermo-sensitive coloring layer of the thermo-sensitive paper, which manifests a pattern of color change in response. Such a printing mechanism is known as a thermal system or '''direct system'''. The paper is impregnated with a solid-state mixture of a dye and a suitable matrix; a combination of a Fluoran Leuco Dye and an Octadecylphosphonic Acid is an example. When the matrix is heated above its melting point, the dye reacts with the acid, shifts to its colored form, and the changed form is then conserved in metastable state when the matrix solidifies back quickly enough. See Thermochromism . APPLICATIONS Thermal printers print faster and more quietly than Dot Matrix Printer s. They are also more economical since their only consumable is the paper itself. Possible commercial applications of thermal printers include Filling Station pumps, information Kiosk s, and Point Of Sale systems. Through the 1990s , many Fax machines used thermal printing technology. Toward the beginning of the 21st Century , however, Thermal Wax Transfer , Laser , and Inkjet printing technology largely supplanted thermal printing technology in fax machines in order to allow plain-paper printouts. Early formulations of the thermo-sensitive coating used in thermal paper were sensitive to incidental heat, Abrasion , Friction (which can cause heat, thus darkening the paper), light (which can fade printed images), and Water . However, more modern thermal coating formulations have resulted in exceptional image stability; theoretically, thermally-printed text should remain legible at least 50 years. SEE ALSO
|
|
|