Wafer Seals and
Glue
At times there may be a reference made to the possible necessity
of wafer seals or glue. Below is a brief overview of some options.
Ask the printer or bindery for more details.
Wafer seals
Wafer seals are small adhesive discs (or other standard or custom
shapes) that are applied to seal the folded piece—most
commonly for mailing purposes, but also for decorative and other
functional purposes as well. To determine how many wafer seals
a given brochure requires, ask your Post Office or mail house.
Wafer sealing is
done mechanically, but bear in mind that most wafer sealing
units have only one head—in other words, most are only
capable of applying one wafer seal at a time per piece. So,
if the folded piece requires more than one wafer seal, that
means more than one pass through the machine, which adds time
and cost. Sometimes it's better to put the piece in an envelope,
both for economical and aesthetic reasons.
Colors—metallics,
colors, standard white, clear, custom printed
Shapes—circular,
diamond, square with rounded corners, thin rectangular (think
tape), custom shapes
Varieties—plain,
perforated, permanent, resealable
Glue
Another option is to glue the open edge of the folded brochure.
This process is done with a special glue attachment on the folding
machine. Glue attachments are not commonplace at most offset
printing plants—gluing is most often used for longer run
web-press jobs such as direct mail. Glue is also cleverly used
in the bindery for other practical reasons such as to pin a
gate fold cover into place as it goes through the saddle stitcher.
The glue would then be sheared off in the final trim.
The glue, commonly
called fugitive glue or "booger glue" is hot or cold,
can be applied in dots or in a stream, and can be used on a
wide range of paper stocks—ask the printer or bindery for
guidelines.
Which is Better?
Both of the
above options are perfectly acceptable methods for sealing the
folded sheet for mailing purposes. Envelopes, of course, are
an excellent and more protective option (and also more costly).
The envelope allows the brochure to remain virtually untouched,
whereas the wafer seal or glue presents an aesthetic issue,
leading to the question of what's worse—a torn wafer seal
stuck to the cover of the brochure, or glue residue on the inside?
As far as pricing goes, glue is generally more economical. Wafer
seals can be costly, especially if multiple seals or custom
designs are required.
