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PROBLEM: Film is not properly adhered or starts to come off some time after
lamination.
SOLUTION: Unless there is something wrong with the film, this problem comes from
film being run at too low a temperature. Check the heat setting on the laminator. If the
film is not sticking to the item, it is likely that more heat is required.
If you are using 1.5-mil film, this problem can occur if you are running the machine too
slowly. Because 1.5-mil film is thin and therefore loses heat easily, it can cool off too
much between the heat shoes and the roller nip if it is run too slowly.
If you are running thicker films, you may have this problem if you try to go too fast. In
this case, the thicker film may not have enough time on the heat shoes to reach its
adhesive melt temperature. Thicker films may be run at low speeds with no problem.
When laminating posters or other thicker material with 1.5-mil film, the paper itself can
absorb enough of the heat from the film to drop the adhesive below its melt tempera-
ture. The film may start to come off immediately, or it may start to fall off after a few
days. The solution here is to run the work at a higher temperature. About 280° to
290 °F will usually do the job.
Sometimes you may see film detach from an item along one edge (the edge that was
put in first). This happens when the material is put all the way into the nip before the
machine is started. The area of film between the shoes and the nip can cool off too
much while the machine is idle. The adhesive may not be hot enough to stick.
The way to prevent this is to let a few inches of film go though before putting in sheets
to be laminated. This serves other purposes besides ensuring the front edge of the
piece will be properly sealed: it gives the machine a chance to take up the slack that
develops in the film whenever the machine is stopped, and it prevents the following
problem as well.
PROBLEM: A laminated item comes out with a large “oily” spot on or near the
leading edge.
SOLUTION: It’s excess adhesive, not oil, that causes this effect. When a machine is
left heated but idle for a few minutes or longer, the adhesive from the film over the
shoes can form droplets if material is not put in immediately. This excess adhesive
saturates an area of paper, creating what looks like an oily spot. The solution, as
mentioned above, is just to let a few inches of film go through before feeding in your
work.
Anytime you are laminating unfamiliar or costly items, it is a good idea to start with an
expendable sample or test piece. Laminating a test piece first gives you an indication of
the results you’ll get and also takes care of any pooled adhesive.
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