Envelope construction is critical. Envelope fold lines can vary considerably, not only between
manufacturers, but also within a box from the same manufacturer. Successful printing on envelopes
depends upon the quality of the envelopes. When selecting envelopes, consider the following
Weight: The weight of the envelope paper should not exceed 90 g/m
(24 lb), or jamming might
Construction: Before printing, envelopes should lie flat with less than 6 mm (0.25 inch) of curl,
and should not contain air. Envelopes that trap air can cause problems. Do not use envelopes
that contain clasps, snaps, tie strings, transparent windows, holes, perforations, cutouts,
synthetic materials, stamping, or embossing. Do not use envelopes with adhesives that require
pressure to seal them.
Condition: Make sure that the envelopes are not wrinkled, nicked, or otherwise damaged.
Make sure that the envelopes do not have any exposed adhesive.