7.0 Thermal Paper - Theory & Specification
The print head’s life expectancy is composed of both a mechanical and an electrical component. Both of
these factors are strongly influenced by the quality of the thermal paper used.
MECHANICAL
The print head has a theoretical rating of 60 kilometers. This number is based upon the assumption that
the head will be used with a good quality, top coated thermal paper. Uncoated and poorly top coated
thermal papers are abrasive to the print head and have been found to wear through the head after less
than one kilometer.
Other factors which may contribute to premature mechanical wear are the use of non-thermal inks and
stray metallic particles stuck in ticket perforations. Certain inks colors such as opaque white (which con-
tains titanium dioxide) are also highly abrasive.
Unfortunately, there are no available devices for quantitatively measuring the abrasiveness of a given
ticket. Fortunately, we have developed a slightly subjective, but effective method of weeding out overly
abrasive ticket stock.
ELECTRICAL
Each heat element, dot, on the print head has a theoretical life expectancy of 100 million activations.
This is based on the assumption that each activation will cause the dot temperature to approach the
dot’s maximum recommended temperature. Running at lower temperatures will increase the theoretical
life expectancy, while slight temperature increases will seriously (exponentially) degrade the head life.
The thermal paper can affect the electrical head life in two ways. Insensitive, slow to image papers, will
typically encourage the user to increase the voltage to darken the printed image. This will directly
increase the head temperature resulting in reduced head life. Additionally, the higher temperatures will
frequently cause the ink to peel off the ticket and deposit onto the print head. The ink debris will disrupt
the normal transfer of heat from the head to the paper. This further increases the head temperature
above the desired level. The use of non-thermal inks and/or non-top coated papers also will cause the
ink to release and deposit on the print head.
SPECIFICATION
Based upon the above technical information, BOCA has always tried to encourage our customers to use
the proper thermal papers to maximize the life of their print heads. BOCA provides an extensive series
of papers which meet the above criteria for low abrasion and high sensitivity. We have also tested and
approved a number of Ricoh thermal papers which meet our criteria. While we have not had the oppor-
tunity to test other manufacturers’ thermal papers, we feel confident that other papers manufactured with
the above goals in mind should be acceptable for use in our printers. The following list of papers have
been approved by BOCA.
300 dpi usage
BOCA
HS7
Please note that the 300 dpi papers may be used on 200 dpi printers. In fact, doing so will increase the
electrical life of the head as this will allow the head to operate at a lower temperature. DO NOT use 300
dpi heads with 200 dpi paper.
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