Envelope Seal Flap And Gum; Storage - Pitney Bowes DocuMatch Integrated Mail System Reference Manual

4 • Envelopes

Envelope Seal Flap and Gum

Mechanical sealing requires seal flap gum that is uniform and
adheres quickly and firmly when moistened. To prevent the
inserting operation from pulling the envelope apart, the seams
must also be securely glued.
Any inserting machine will jam if there is even the slight-
est tendency for the seal flap to adhere to the envelope's
back. On many styles of envelopes, the seal flap gum is the
first adhesive applied, and it is dried before the envelope goes
through the folding and seam gumming process. During the
manufacturing of die-cut envelopes, for instance, the enve-
lope does not go through another drying process. This trans-
lates to the seam gum being damp when the envelopes are
packed into boxes. The compression of the envelopes in the
boxes may cause the damp seam gum to remoisten the seal
flap gum, which in turn, may cause the flap to tack. This chain
of events can cause problems during the insertion process.
When you are ordering envelopes from your business forms
vendor or supplier, you should make it clear that you require
envelopes designed for automatic insertion. A knowledgeable
vendor should be able to review the DocuMatch envelope
requirements in this chapter and supply you with the kinds of
envelopes that will optimize your DocuMatch mail jobs.

Storage

Because of the glue used in their construction, proper storage
is especially important for envelopes. If they become too dry,
some envelopes will develop curled flaps, which can cause
flap opening problems. Too much moisture can cause enve-
lopes to warp or curl excessively, which can cause feeding
problems. Always store envelopes in closed boxes until ready
for use. It is best to remove the envelopes from the
DocuMatch ™ hopper and return them to a box if you know the
system will be idle for several hours or overnight.
4-8 DocuMatch ™ Mail Materials Reference Guide