Lexmark 22L0176 - C 770dn Color Laser Printer Manual page 16

Label components
finishes have varying degrees of surface smoothness. The smoothness is determined by the number of times the paper
passes through the rollers (wet or dry) during manufacturing. An English finish is uncoated and low gloss in appearance.
Label papers may also be used as the face sheet for pressure-sensitive paper products, such as the materials used in dual
web forms construction.
Supercalendering produces high gloss surfaces that may be slick. Some supercalendered liners are difficult for printers to
pick and feed reliably. We do not recommend using supercalendered liners designed for high-speed laser printers (50 or
more pages per minute).
Some pressure-sensitive constructions use Kraft liners or bleached Kraft liners. Kraft liners are made from sulfate pulp and
are M.F. or M.G. (machine glazed). Most machine glazed papers have a high gloss appearance. High gloss, glazed
surfaces may increase skew and are more difficult for the printer feed mechanism to handle reliably. Some Kraft liners may
produce acceptable results; however, we strongly recommend extensive testing of pressure-sensitive constructions using
Kraft liners.
Tissue-backed or plain bond liners reduce toner contamination inside the printer and improve feed performance. Slick, non-
porous liners are harder to feed and increase toner buildup in the fuser and on the backup roll. Rough backings, on the
other hand, can increase paper path friction, which can cause skew and paper jams. The face material of the liner needs to
have a melt temperature that can also withstand the fuser temperatures of nearly 225°C (437°F). Since there is a stripped
area of a maximum of 3 mm, this can expose the face material to these temperatures and could cause melting or
contamination in the fuser.
Excessive paper dust or chaff associated with the liner may affect print quality. If a liner material produces excessive paper
dust or chaff during the conversion process, some of this debris may be packaged with the material and end up in the
printer. Liner materials that produce excessive paper dust or chaff as they feed through the printer may also affect print
quality.
Your forms supplier can provide additional information on liners.
Adhesives
There are three basic types of label adhesives: removable, permanent, and semi-permanent (cold temp). All types, with
proper design, can be used with your printer. Acrylic-based adhesives are generally preferred for cut sheet label printers.
The major adhesive-related printing problem is printer and cartridge contamination. The adhesives are semi-liquid and may
contain volatile components. If the sheet jams in the fuser, the adhesive can melt, thereby contaminating parts of the printer
or releasing fumes. To avoid exposing adhesive to the paper path guides, drive rollers, charge roller, photoconductor drum,
transfer roller, and detack fingers, use full label sheets.
Zone coating means placing the adhesive only where needed. Paper labels and integrated forms typically use zone
coating. In addition, a non-adhesive border of 1 mm (0.04 in.) around the outside edge of the label sheet generates good
results. Check with your adhesive manufacturer or forms supplier for more information about designing labels for your
printer.
A stripped edge matrix along the outer border of the stock, combined with adhesive that does not ooze, helps prevent
adhesive contamination. This design requires a stiffer backing material to prevent damage when the sheet is aligned on the
reference edge. Generally, vinyl and polyester labels are well-suited for this design. Paper and dual web designs may
require testing to determine which backing produces good results. (See Label design guidelines on page 17 for more
information on matrices.)
Make sure the release strength is adequate so labels stay attached to the liner and do not peel off in the printer. Adhesives
must be able to withstand pressures to 25 psi and fuser temperatures of 225°C (437°F) without delaminating, creating
hazardous fumes, or oozing around edges of labels, perforations, or die-cuts. Shear strength should be strong enough to
prevent adhesive stringers. Contact your forms supplier for additional information.
Face sheet (printable stock)
Paper, vinyl, and polyester are the most common materials used for printable stock. Your forms supplier can provide
information on whether the printable stock you want to use can withstand temperatures of 225°C (437°F) [temperatures
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