Opening device and method for manufacturing the same, and a packaging material provided with said opening device

Patent metadata

Field	Value
Publication number	US-10399738-B2
Application number	US-201615339124-A
Country	US
Kind code	B2
Filing date	Oct 31, 2016
Priority date	Dec 14, 2009
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

An opening device for a packaging container, the packaging container being formed from a packaging material having an upper side constituting the outside of the packaging container and a lower side constituting the inside of the container, the opening device including two operational parts, a preformed support part arranged on the upper side of the packaging material and a membrane part arranged on the lower side of the container and extending into openings of the support part such as to mechanically connect the two parts, and wherein the materials of the membrane part and the support part are thermally incompatible polymer materials.

First claim

The invention claimed is:

1. A method for manufacturing an opening device comprising:
arranging a preform in a first mold half, the preform including through openings;
arranging the first mold half on a first side of packaging material, in register with a hole pattern of the packaging material, so that the through openings of the preform are in register with the hole pattern of the packaging material;
arranging a second mold half on a second side of the packaging material so that at least one mold cavity is defined by the mold halves, the preform and the packaging material; and
injecting a melt of polymer material that is thermally incompatible with the preform into the at least one mold cavity to cause the melt to at least partly penetrate through the through openings of the preform and through the packaging material at the hole pattern of the packaging material so that the preform is a support part of the opening device and the injected melt is a membrane part of the opening device,
wherein: i) the packaging material is a laminate that includes a cardboard core sandwiched between coating layers of polymer and a metallic foil between the cardboard core and one of the coating layers of polymer; ii) the hole pattern of the packaging material includes a plurality of spaced-apart through holes in the cardboard core each covered by the metallic foil; and iii) the injecting of the melt of polymer material includes injecting the melt of polymer material so that the melt of polymer material penetrates the metallic foil spanning the through holes in the cardboard core.

2. The method according to claim 1 , further comprising advancing a movable part inside the mold cavity to reduce a volume of the mold cavity locally and form a weakening line in the membrane part after the injection of the melt of polymer material.

3. The method according to claim 1 , further comprising allowing the melt of polymer material to cool, after the injecting of the melt of polymer material, so that the polymer material shrinks in the openings of the preform to seal the openings of the preform.

4. The method according to claim 1 , wherein the through openings of the preform possess a conical shape.

5. The method according to claim 1 , wherein the melt of polymer material is thermally compatible with the packaging material.

6. The method according to claim 1 , wherein
one portion of the membrane part of the opening device penetrates through at least one of the through openings after the opening device is formed, and
an other portion of the membrane part of the opening device is positioned below the at least one through opening of the support part after the opening device is formed.

7. The method according to claim 1 , wherein dimensions of the membrane part on both sides of the at least one opening exceed dimensions of the at least one opening.

8. The method according to claim 1 , wherein the through openings of the support part possess an axial extent and a varying cross-sectional size along the axial extent to mechanically connect the membrane part to the support part by way of the through openings.

9. A method for manufacturing an opening device comprising:
arranging a support part on an upper side of packaging material, the support part comprising at least one opening and the packaging material comprising a hole pattern, the support part being made of a material;
positioning the support part relative to the packaging material so that a portion of the support part fits in the hole pattern of the packaging material;
injecting a polymer material on a lower side of the packaging material so that the polymer material at least partly penetrates through the packaging material and into the at least one opening of the support part, the polymer material being a melted polymer which is thermally incompatible with the material from which the support part is made; and
allowing the melted polymer material to cool after the polymer material at least partly penetrates through the packaging material and into the at least one opening of the support part so that the polymer material shrinks in the at least one opening of the support part and forms a membrane part of the opening device,
wherein: i) the packaging material is a laminate that includes a cardboard core sandwiched between coating layers of polymer and a metallic foil between the cardboard core and one of the coating layers of polymer; ii) the hole pattern of the packaging material includes a plurality of spaced-apart through holes in the cardboard core each covered by the metallic foil; and iii) the injecting of the polymer material includes injecting the polymer material so that the polymer material penetrates the metallic foil spanning the through holes in the cardboard core.

10. The method according to claim 9 , further comprising
surrounding the support part on the upper side of the packaging material with a first mold half;
surrounding the lower side of the packaging material with a second mold half such that a mold cavity is defined between the first mold half and the second mold half; and
the injection of the polymer material including injecting the polymer material into the mold cavity formed between the first mold half and the second mold half.

11. The method according to claim 10 , further comprising advancing a movable part inside the mold cavity to reduce a volume of the mold cavity locally and form a weakening line in the membrane part after the injection of the polymer material.

12. The method according to claim 9 , wherein the support part possesses a first surface facing the packaging material and an oppositely facing second surface, the at least one opening of the support part being a through opening that opens to the first and second surfaces of the support part, the through opening possessing a cross-section that varies along its length so that the cross-section of a portion of the through opening that opens to the second surface is larger than the cross-section of a portion of the through opening that opens to the first surface.

13. The method according to claim 9 , wherein the at least one opening of the support part is a through opening possessing a conical shape.

14. The method according to claim 9 , wherein the melt of the polymer material is thermally compatible with the packaging material.

15. The method according to claim 9 , wherein
a portion of the membrane part of the opening device penetrates through the at least one opening of the support part after the opening device is formed, and
an other portion of the membrane part of the opening device remains below the at least one opening of the support part after the opening device is formed.

16. The method according to claim 9 , wherein dimensions of the membrane part on both sides of the at least one opening exceed dimensions of the at least one opening.

17. The method according to claim 9 , wherein the at least one opening in the support part comprises plural openings in the support part, each of the openings in the support part possessing an axial extent and a varying cross-sectional size along the axial extent to mechanically connect the membrane part to the support part by way of the openings.

Assignees

• Tetra Laval Holdings & Finance

Inventors

• Andersson Pär

Classifications

• B65D5/72

  Contents-dispensing means · CPC title

• B29L2031/565

  for containers · CPC title

• B65D17/4011 Primary

  for opening completely by means of a tearing tab · CPC title

• B29C45/14754 Primary

  being in movable or releasable engagement with the coating, e.g. bearing assemblies · CPC title