Stock material for container body of insulating paper container, insulating paper container and process for making them
View Patent ↗An insulating paper container's body has a low m.p. thermoplastic synthetic resin film laminated on its outer wall surface and a compatibly expansile ink applied to the outer surface either as a primer or as indicia to provide stock material improved in its printability for bar codes or the like as well as in its insulating property. In addition there is provided a process for making such stock material.
1. Stock material for a container body of an insulating paper container, comprising:
a base paper layer;
a thermoplastic resin film laminated on a surface of the base paper layer, and expanded with heat treatment;
an ink layer applied to at least a portion of an outer surface of the thermoplastic resin film, which ink expands commensurately with the expansion of the thermoplastic resin film; and
an ink layer at least partially filling an interface defined between the base paper layer and the thermoplastic resin film, which ink expands commensurately with the expansion of the thermoplastic resin film.
2. A stock material according to claim 1 , wherein the ink layer is applied as a primer on the outer surface of the thermoplastic resin film.
3. The stock material according to claim 1 , wherein the thermoplastic resin film is made of a low density polyethylene having a melt flow rate of 8-15 g/10 min and a thickness of 0.03-0.07 mm.
4. An insulating paper container comprising:
a container body and a bottom wall formed from at least one base paper layer;
an expanded thermoplastic resin film laminated on an outer wall surface of the base paper layer of the container body; and
an ink layer applied to at least a portion of an outer surface of the thermoplastic resin films, which ink expands commensurately with the expansion of the thermoplastic resin film; and
an ink layer at least partially filling an interface defined between the base paper layer and the thermoplastic resin film, which ink expands commensurately with the expansion of the thermoplastic resin film.
5. The insulating paper container of claim 4 , wherein the thermoplastic resin film is laminated on an outer wall surface of the base paper layer of the bottom wall and is expanded by subjecting the outer wall surface of the base paper layer of the bottom wall to a heat treatment.
6. The insulating paper container of claim 4 , wherein the thermoplastic resin film comprises a low density polyethylene having a melt flow rate of 8-15 g/10 min and a thickness of 0.03-0.07 mm.