TAMPER PROOF BOTTLE CAP

• US 3,720,343 A
• Filed: 11/19/1971
• Issued: 03/13/1973
• Est. Priority Date: 11/19/1971
• Status: Expired due to Term

• Current Assignee: Edwin M. Irish Jr
• Original Assignee: Edwin M. Irish Jr
• Inventors: Irish, Edwin M. Jr.
• Primary Examiner(s): Hall, George T.
• Application Number:
  US05/200,397
• Time in Patent Office: 480 Days
• Field of Search: 215/38A,7,42,46A
• US Class Current: 215/246
• CPC Class Codes: B32B 15/046 of foam
• CPC Class Codes: B32B 15/082 comprising vinyl resins; comprising acrylic resins
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: B32B 2435/02 for containers
• CPC Class Codes: B32B 27/304 comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
• CPC Class Codes: B65D 39/02 Disc closures discs with flanges B65D39/04
• CPC Class Codes: B65D 41/54 Caps or cap-like covers made of shrinkable material or formed in situ by dipping, e.g. using gelatine or celluloid
• CPC Class Codes: B65D 45/00 Clamping or other pressure-applying devices for securing or retaining closure members screw-threaded or bayonet connections between stoppers or caps and containers B65D39/08, B65D41/04, B65D41/34; expansible stoppers B65D39/12; for pressure vessels in general F16J13/00

Abstract

A milk bottle cap, apparatus and method, especially adapted as tamperproof closures for plastic milk bottles and the like. The bottle cap comprises a laminated disc structure containing a top layer of a rigid material, preferably an impervious plastic material, an intermediate layer which can be aluminum foil or the like, and a plastic foam disc for contact with the bottle opening. The disc, when placed on the bottle opening, is then sealed in place over the bottle opening and maintained in place by a heat shrink tube which is heat shrunk around and partially over the closure disc, and sealed thereto, and having a depending skirt in intimate sealing contact with the threads on the neck of the bottle. A tear strip is provided to initially break the seal to permit removal. The heat shrink material has sufficient strength and rigidity whereby the cap can be re-engaged, after removal, on the bottle threads for reclosure of the bottle.

Claims

1. A closure cap for threaded neck plastic containers and the like comprising:

a. a laminated top disc adapted to engage over, and in sealing relationship with a container opening;

b. a heat shrinkable plastic tube partially extending and engaging over and combined with said top disc, said tube;

i. beiNg partially heat shrunk into said engagement with said top disc; and

ii. including a depending skirt adapted for sealing engagement over and with the threaded neck of a container by further heat shrinking subsequent to placement of the cap on a container.

2. A closure cap as claimed in claim 1, wherein said tube consists of thin-wall rigid polyvinylchloride heat-shrinkable tubing.

3. A closure cap as claimed in claim 2, wherein said laminated top disc comprises an upper disc of plastic material, an intermediate disc of aluminum foil and a lower disc of compressible material having sufficient resilience to make a leak-proof seal with the container opening.

4. A closure cap as claimed in claim 2, wherein said laminated disc includes a layer of aluminum foil, an upper layer of material of substantially rigid material and a lower layer of resilient material, said layers being adhesively secured to one another.

5. A closure cap as claimed in claim 3, wherein the top layer consists of rigid polyvinylchloride sheet material, said aluminum foil having a vinyl heat-seal thereon and the lower layer consisting of a foamed plastic material resilient in nature.

6. A closure cap as claimed in claim 5, wherein said upper layer and said foil are adhesively sealed by the application of heat to the vinyl heat-sealed coat, said foil and said foamed plastic being adhesively secured by a pressure sensitive adhesive.

7. A closure cap as claimed in claim 1 and including a tear strip and tab in said depending skirt, said tear strip constituting tamper-proof detection means and on removal permitting removal of the cap from a container and rethreading on the threaded neck plastic container.

8. A closure cap as claimed in claim 1, wherein said tube consists of thin-wall rigid heat shrinkable tubing of oriented polymeric material.