Thermally laminated tab liner
AssigneeTekni-Plex, Inc.
InventorPhilip D. Bourgeois
Life of this patent
Estimating the term…
Abstract
Liner having an induction heat sealable layer for sealing to a rim of a container, and a pull tab for ease of removal of the liner from the container rim. An insert is disposed between multilayer upper and lower components, has a heat bondable polyolefin layer that is thermally laminated to polyolefin layers of the upper and lower components, forming a pull tab between the integrated polyolefin layers. The resulting composite resists delamination and can be formed in a single thermal lamination step, avoiding the multiple lamination steps, associated high equipment costs, and complex layer constructions of the prior art.
Claims16
A method of forming an induction heat sealable liner for sealing to a rim of a container, the method comprising:
- providing three separate multi-layer components comprising:
- an upper multilayer component (UMC) comprising an upper support layer and a lower heat bondable polyolefin layer;
- and
- a lower multilayer component (LMC) comprising an upper heat bondable polyolefin layer, a lowermost induction heat sealable layer for sealing to a rim of a container, and an inductive heating layer therebetween;
- an insert comprising an upper heat bondable polyolefin insert layer and a lower heat resistant separable layer,
- stacking the three multi-layer components and thermally laminating the stacked composite to form a composite liner, wherein the method includes:
- disposing a first area of the UMC and LMC heat bondable polyolefin layers facing one another,
- disposing the insert between a second area of the UMC and LMC heat bondable polyolefin layers such that the lower heat resistant separable layer is facing the LMC heat bondable polyolefin layer, and the UMC and insert heat bondable polyolefin layers are facing one another, and
- forming a non-separable first liner portion during the thermally laminating step by at least partially melting the facing UMC and LMC heat bondable polyolefin layers in the first area by application of heat and pressure to form an integral polyolefin layer in the first liner portion of the composite liner, and
- forming a second liner portion having a pull tab formed in the second area by at least partially melting the facing insert and UMC heat bondable polyolefin layers to form an integral polyolefin layer in the second liner portion of the composite liner;
- and
- attaching the composite liner to a container rim by induction heat sealing, wherein the heat resistant separable layer resists bonding during both the thermally laminating and the induction heat sealing to produce the pull tab in the second liner area.
Dependencies are inferred from the claim text.