Heat sealing and packaging
AssigneeThe Crowell Corporation
InventorLewis R. Raszewski
Life of this patent
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Abstract
Sealing of elongated packaging laminates of backed antistatic foam around spaced articles being packaged, using edge seals made by first applying heated melting shoes against foam edges of both laminates, then joining the melted foam edges and subjecting the assembly to rollers that press together the joined laminates. Preferably the backing has aluminum layer secured to the foam by pressure-sensitive adhesive. Edge seals can be further subjected to pressure sustained for at least about a second, as while similar pressure is used to apply transverse heat seals to the edge-jointed laminates.
Claims8
In the process of packaging articles between two elongated wrapping laminates each having a layer of antistat foam laminated to a backing web and the foam layer of one laminate is heat sealed to the foam layer of the other laminate while the elongated laminates are advanced by side edge rollers through a heat sealing zone as articles to be heat sealed are sandwiched between them, the improvement according to which the laminates are prepared for the heat sealing by melting the foam at the side edges of both laminates at their heat sealing sites, and the laminates with the melted foam edges are pressed together to heat seal them together after an article is sandwiched between them.
Dependencies are inferred from the claim text.