Principles Of The Lamination Process - usi CRL 40 Instruction Manual

5.

PRINCIPLES OF THE LAMINATION PROCESS

The lamination process uses a specialised laminating film consisting of a heat stable base film (polyester)
coated with an adhesive co-polymer resin. Whilst dry to touch at room temperatures, at approx 250 o F the
resin softens into a very aggressive contact adhesive. Two webs of the coated film are drawn over a
matching pair of hot surfaces (heat shoes) to heat activate the resin. They are passed between two heated
rubber rollers under pressure to form a hot sticky sandwich of film. Two pull rollers stretch the film flat
while it is being cooled by fans. Articles are fed between the two film layers as they enter the laminating nip
and are encapsulated between the two film webs.
Under heat and pressure the two adhesive film layers impregnate the article's surface with molten adhesive
providing a long lasting flexible airtight seal. The cooled adhesive film forms part of the strength of the
laminate.
The key points affecting the quality of a lamination are the quality of the laminating film used, the heat shoe
design and the quality and temperature of the heated rubber nip rollers.
Fig 5.1 THE PROCESS
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