Oki LD670 User Manual page 6

(10) If label paper is used, adhesive matter adhering to the cutter blade, thermal head,
paper transport, or paper holder may cause a cutting error, print error, or paper
transport error. Remove adhesive matter periodically (typically on a monthly
basis).
(11) If paper is left inserted in the printer for a long time, the paper may become
deformed and result in thin (faint) printed characters. Before starting printing
in such cases, feed the paper by 20 to 30 mm.
(12) If the type of paper used is other than the recommended ones, the print quality
and thermal head life are not guaranteed. In particular, if the type of thermal
paper contains Na+, K+, or Cl-, the thermal head life may be significantly
shortened.
(13) When using full-sheet label paper, note that the paper may adhere to the head
and cause noise if the top margin is less than 3 mm. You should therefore set
the top margin to 3 mm or a greater value when printing on this type of paper.
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