Vinyl surface issues (rough, dull or mottled)
• Mottling or a dull finish is common among highly pliable and conformable cast
and calendered vinyl. The surface of the film can appear to be slightly dull as
the liner leaves minor embossing.
Mottling usually occurs when a roll of graphic film is wound too tightly or
stored at a high humidity. It is not a surface defect and will disappear
within a few days of installation. To remove mottling prior to cutting or
printing, release the tension of the roll for a few days by loosening the tape
used to fasten the end of the roll. Applying light heat with a heat gun will also
• Thermal printing on mottled film could create an undesired printing effect. For
optimal results, use the suggestions above to remove mottling prior to thermal
Special Considerations and Uses
Mottling is a special consideration for vinyl films. Mottle looks like a haze, or blotchy
dull spots on the vinyl film surface. This condition occurs when the glossy top surface
of soft, conformable vinyl film is pressed against the release liner in a wound roll.
While conform-ability is a benefit of vinyl films, it also makes them prone to mottling.
Factors affecting the level and severity of mottle include heat, time wound in a roll,
roll tightness, film formulation, and liner type. Also, film color and gloss level have an
effect. Mottle will show up more on higher gloss films and darker colors.
(TIP) To prevent mottle, store vinyl films in a cool area, away from direct sunlight or a
heat source. Rolls should be wound as loosely as possible and suspended or kept in
boxes with end plugs. Laying rolls on their sides can produce a "band" of mottle.
(TIP) Mottle can be reversed. To eliminate mottle, unroll the vinyl and leave it lying in
a warm area. Or, carefully use a heat gun (or hand-held hair dryer) over the film
surface. The mottle should begin to disappear. Once film is applied to a substrate,
most mottle will eventually disappear with time and exposure to heat or sunlight.