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Most label printer use direct
thermal printing. This is how the direct thermal printing process works. A
direct thermal printer produces a printed image by selectively heating
specially coated themochromic paper when the paper passes over the thermal
printhead. The coating turns black in the areas where it is heated,
producing the image. Two-colour
direct
thermal printers are capable of printing both black and a one additional
colour by applying heat at two different temperatures.
Thermal transfer printing is a related method that uses a heat-sensitive
ribbon
instead of thermal paper. A thermal printer comprises several key
components: The thermal head generates heat and prints on paper. The platen
is a rubber roller that feeds paper. The spring applies pressure to the
thermal head, causing it to contact the thermo sensitive paper. Lastly, the
controller board controlling the printing mechanism
In order to print, the thermo-sensitive paper is inserted 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
designated pattern. The heat activates the thermo-sensitive colouring layer
of the thermo-sensitive paper, which manifests a pattern of colour change in
response. Such a printing mechanism is known as a thermal system or direct
system.
Controller boards use embedded firmware to control the thermal printer
mechanisms. These controller boards features are designed to meet the
labelling needs in terms of functionality and printer
specifications. The firmware can manage multiple bar code types, logos, and
graphics. They enable the user to choose between different resident fonts,
including Asian fonts, and different character sizes. Controller boards can
drive various sensors like paper low, paper out, door open, top of form to
name but a few, and they are available with the most commonly used
interfaces. |