Laminated lidstock

• US 20090178945A1
• Filed: 06/13/2008
• Published: 07/16/2009
• Est. Priority Date: 01/11/2008
• Status: Active Grant

• Current Assignee: Cryovac Incorporated (Sealed Air)
• Original Assignee: Cryovac Incorporated (Sealed Air)
• Inventors: Moehlenbrock, Andrew W., Wilson, Douglas, Stephens, Chad, Karam, Debra C.
• Granted Patent: US 7,681,732 B2
• Time in Patent Office: Days
• US Class Current: 206/484
• CPC Class Codes: B32B 2250/24 All layers being polymeric
• CPC Class Codes: B32B 2250/44 Number of layers variable across the laminate
• CPC Class Codes: B32B 2255/10 on synthetic resin layer or on natural or synthetic rubber layer
• CPC Class Codes: B32B 2255/26 Polymeric coating
• CPC Class Codes: B32B 2270/00 Resin or rubber layer containing a blend of at least two different polymers
• CPC Class Codes: B32B 2307/31 Heat sealable
• CPC Class Codes: B32B 2307/4023 on the layer surface, e.g. ink
• CPC Class Codes: B32B 2307/7244 Oxygen barrier
• CPC Class Codes: B32B 2307/748 Releasability
• CPC Class Codes: B32B 2307/75 Printability
• CPC Class Codes: B32B 2439/62 Boxes, cartons, cases
• CPC Class Codes: B32B 2439/70 Food packaging
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/18 characterised by the use of special additives
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/34 comprising polyamides
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: B32B 3/10 characterised by a discontinuous layer, i.e. formed of separate pieces of material
• CPC Class Codes: B32B 3/266 characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
• CPC Class Codes: B32B 7/06 : permitting easy separation
• CPC Class Codes: B32B 7/12 : using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: B32B 7/14 : applied in spaced arrangements, e.g. in stripes
• CPC Class Codes: B65D 2577/205 : integral with the closure
• CPC Class Codes: B65D 77/206 : so as to uncover one or more preformed openings made through some layers of the cover
• CPC Class Codes: B65D 77/2096 : Adhesive means
• CPC Class Codes: Y10S 206/807 : Tamper proof
• CPC Class Codes: Y10S 428/915 : Fraud or tamper detecting
• CPC Class Codes: Y10T 156/1052 : with cutting, punching, tearing or severing
• CPC Class Codes: Y10T 428/1486 : Ornamental, decorative, pattern, or indicia

Abstract

A laminated lidstock includes a substrate film, a support web; a pressure sensitive adhesive disposed between the substrate and support webs, and covering the substrate film and support web except for a clear area disposed near one end of the laminated lidstock; a first die cut disposed in the substrate film; a second die cut disposed in the support web; a pull tab; and a tamper evidence device including an end portion of the support web, defined by a first end, a first side edge, and a second side edge of the package made from the laminated lidstock, and the second die cut, capable of indicating tampering of the package upon removal of the tamper evidence device from the support web; wherein at least one of the substrate film and the support web carries a registration device.

Claims

1. A laminated lidstock comprising:

a) a substrate film comprising

i) an outer laminating layer comprising a thermoplastic material, the outer laminating layer having an outer surface to which a support web can be adhered with a pressure sensitive adhesive; and

iii) an inner sealing layer comprising a thermoplastic material, the inner layer having a surface which can be sealed to a tray;

b) a support web comprising having an outer surface and an inner surface, comprising a thermoplastic material selected from polyester, polyamide, and polyolefin;

c) a pressure sensitive adhesive disposed between the substrate film and the support web, and covering the outer surface of the outer laminating layer of the substrate film, and the inner surface of the support web except for a clear area disposed near, and spaced from, a first end of the laminated lidstock;

d) a first die cut disposed in the substrate film, but not substantially present in the support web;

e) a second die cut disposed in the support web, but not substantially present in the substrate film;

f) a pull tab spaced, apart from a first end of a package made from the laminated lidstock, comprising an intermediate portion of the support web, spaced from the first die cut, defined by the second die cut, a first side of a package made from the laminated lidstock, and a second side edge of a package made from the laminated lidstock; and

g) a tamper evidence device disposed at one end of the laminated lidstock, the tamper evidence device comprising a first end portion of the support web, defined by a first end of a package made from the laminated lidstock, a first side edge of the package made from the laminated lidstock, a second side edge of the package made from the laminated lidstock, and the second die cut, the tamper evidence device capable of indicating tampering of the package upon removal of the first end portion of the support web from the substrate film;

wherein at least one of the substrate film and the support web carries a registration device.

2. The laminated lidstock of claim 1 wherein at least one of substrate film and the support web comprises an oxygen barrier having an oxygen permeability, of the barrier material, less than 50 cm³ O₂/m²·

day·

atmosphere measured at a thickness of 1 mil (ASTM D

     3985).

3. The laminated lidstock of claim 1 wherein the support web comprises a coating, adhered to the outer surface of the support web, comprising the oxygen barrier material.

4. The laminated lidstock of claim 1 wherein the second die cut comprises a score.

5. The laminated lidstock of claim 1 wherein printed indicia is disposed on at least one of

(a) the outer surface of the outer laminating layer of the substrate film, and

(b) the inner surface of the support web;

such that the printed indicia are disposed between the substrate film and the support web.

6. The laminated lidstock of claim 1 wherein the tamper evidence device comprises a printed message disposed on the outside surface of the substrate film, near the first end of the lidstock, and a printed portion disposed on the support web, in covering relationship to the printed message, such that the printed message is hidden until the first end portion of the support web is removed from the substrate film.

7. The laminated lidstock of claim 1 wherein the tamper evidence device comprises a discrete label disposed on the outside surface of the laminated lidstock, and overlapping the second die cut, such that the label is distorted when the first end portion of the support web is removed from the substrate film.

8. A method of making a laminated lidstock comprising:

a) providing a substrate film comprising;

i) an outer laminating layer comprising a thermoplastic material, the outer laminating layer having an outer surface to which a support web can be adhered with a pressure sensitive adhesive;

ii) an inner sealing layer comprising a thermoplastic material, the inner sealing layer having an inner surface which can be sealed to a tray;

b) providing a support web, having an outer surface and an inner surface, comprising a thermoplastic material selected from polyester, polyamide, and polyolefin;

c) applying a coating of pressure sensitive adhesive to substantially the entire inner surface of the support web;

d) providing, in a selected portion of the inner surface of the support web, a clear area near and spaced apart from a first end of the support web;

e) curing the coating of pressure sensitive adhesive;

f) bringing the substrate film and the support web together such that the pressure sensitive adhesive is disposed between the substrate film and the support web, covers the outer surface of the substrate film and the inner surface of the support web except for the clear area disposed near and spaced apart from one end of the support web, and adheres the substrate film and the support web together;

g) making a first die cut in the substrate film, but not substantially in the support web; and

h) making a second die cut in the support web, but not substantially in the substrate film;

such that a pull tab is provided, spaced apart from a first side edge of a package made from the laminated lidstock, the pull tab comprising an intermediate portion of the support web, spaced from the first die cut, defined by the second die cut, a first side edge of a package made from the laminated lidstock, and a second side edge of a package made from the laminated lidstock; and

a tamper evidence device is provided at one end of the laminated lidstock, comprising a first end portion of the support web, defined by the first end of a package made from the laminated lidstock, the first side edge of a package made from the laminated lidstock, the second side edge of a package made from the laminated lidstock, and the second die cut, the tamper evidence device capable of indicating tampering of the package upon removal of the first end portion of the support web from the substrate film.

9. The method of claim 8 wherein at least one of substrate film and the support web comprises an oxygen barrier having an oxygen permeability, of the barrier material, less than 50 cm³ O₂/m²·

day·

atmosphere measured at a thickness of 1 mil (ASTM D

     3985).

10. The method of claim 8 wherein the support web comprises a coating, adhered to the outer surface of the support web, comprising the oxygen barrier material.

11. The method of claim 8 wherein the second die cut comprises a score.

12. The method of claim 8 wherein the printed indicia is disposed on at least one of

(a) the outer surface of the outer laminating layer of the substrate film, and

(b) the inner surface of the support web;

such that the printed indicia are disposed between the substrate film and the support web.

13. The method of claim 8 wherein the tamper evidence device comprises a printed message disposed on the outside surface of the substrate film, near the first end of the lidstock, and a printed portion disposed on the support web, in covering relationship to the printed message, such that the printed message is hidden until the first end portion of the support web is removed from the substrate film.

14. The method of claim 8 wherein the tamper evidence device comprises a discrete label disposed on the outside surface of the laminated lidstock, and overlapping the second die cut, such that the label is distorted when the first end portion of the support web is removed from the substrate film.

15. A tamper evident reclosable package comprising:

a) a tray comprising a tray bottom, tray sides, and a tray flange, wherein the tray bottom and tray sides define a tray cavity;

b) a food product disposed in the tray cavity; and

c) a laminated lidstock, hermetically sealed to the tray flange, comprising

i) a substrate film comprising

(a) an outer laminating layer comprising a thermoplastic material, the outer laminating layer having an outer surface to which a support web can be adhered with a pressure sensitive adhesive, and

(b) an inner sealing layer comprising a thermoplastic material, the inner sealing layer having a surface which can be sealed to the tray flange;

ii) a support web having an outer surface and an inner surface, comprising a thermoplastic material selected from polyester, polyamide, and polyolefin;

iii) a pressure sensitive adhesive disposed between the substrate film and the support web, and covering the outer surface of the outer laminating layer of the substrate film and the inner surface of the support web except for a clear area disposed near and spaced apart from a first end of the package;

iv) a first die cut disposed in the substrate film, but not substantially present in the support web;

v) a second die cut disposed in the support web, but not substantially present in the substrate film;

vi) a pull tab, spaced apart from a first end of the package, the pull tab comprising an intermediate portion of the support web, spaced from the first die cut, defined by the second die cut, a first side edge of the package, and a second side edge of the package; and

vii) a tamper evidence device disposed at one end of the laminated lidstock, the tamper evidence device comprising a first end portion of the support web, defined by the first end of the package, the first side edge of the package, the second side edge of the package, and the second die cut, the tamper evidence device capable of indicating tampering of the package upon removal of the first end portion of the support web from the substrate film;

wherein the inner sealant layer of the substrate film is sealed to the tray flange.

16. The package of claim 15 wherein at least one of substrate film and the support web comprises an oxygen barrier having an oxygen permeability, of the barrier material, less than 50 cm³ O₂/m²·

day·

atmosphere measured at a thickness of 1 mil (ASTM D

     3985).

17. The package of claim 15 wherein the support web comprises a coating, adhered to the outer surface of the support web, comprising the oxygen barrier material.

18. The package of claim 15 wherein the second die cut comprises a score.

19. The package of claim 15 wherein printed indicia is disposed on at least one of

(a) the outer surface of the outer laminating layer of the substrate film, and

(b) the inner surface of the support web;

such that the printed indicia are disposed between the substrate film and the support web.

20. The package of claim 15 wherein the tamper evidence device comprises a printed message disposed on the outside surface of the substrate film, near the first end of the lidstock, and a printed portion disposed on the support web, in covering relationship to the printed message, such that the printed message is hidden until the first end portion of the support web is removed from the substrate film.