Container closure wth liner and method of producing the same

• US 5,542,557 A
• Filed: 08/09/1994
• Issued: 08/06/1996
• Est. Priority Date: 05/09/1991
• Status: Expired due to Term

• Current Assignee: TOYO Seikan Kaisha Limited (Toyo Seikan Group Holdings, Ltd.)
• Original Assignee: TOYO Seikan Kaisha Limited (Toyo Seikan Group Holdings, Ltd.)
• Inventors: Kikuchi, Hiroaki, Yamada, Muneki, Oda, Yasuhiro, Koyama, Masayasu
• Primary Examiner(s): Shoap, Allan N.
• Assistant Examiner(s): MCDONALD, CHRISTOPHER
• Application Number:
  US08/288,201
• Time in Patent Office: 728 Days
• Field of Search: 206/0.7, 215/348, 215/350, 215/341, 215/228, 215/347, 426/118, 426/124, 220/378
• US Class Current: 215/347
• CPC Class Codes: B29C 59/02 by mechanical means, e.g. pressing B29C59/007 takes precedence; embossing expanded porous articles B29C44/5627
• CPC Class Codes: B29C 70/80 Moulding sealing material into closure members placing sealings in closures B21D51/46
• CPC Class Codes: B29C 70/84 by moulding material on preformed parts to be joined joining plastic parts by moulding B29C65/70
• CPC Class Codes: B29K 2023/0633 LDPE, i.e. low density polyethylene
• CPC Class Codes: B29K 2023/083 EVA, i.e. ethylene vinyl acetate copolymer
• CPC Class Codes: B29K 2105/0011 Biocides
• CPC Class Codes: B29K 2105/0032 Pigments, colouring agents or opacifiyng agents
• CPC Class Codes: B29K 2105/0041 Anti-odorant agents, e.g. active carbon
• CPC Class Codes: B29K 2105/0044 Stabilisers, e.g. against oxydation, light or heat
• CPC Class Codes: B29K 2105/0085 Copolymers
• CPC Class Codes: B29K 2105/0088 Blends of polymers
• CPC Class Codes: B65D 51/244 provided with oxygen absorbers
• CPC Class Codes: B65D 51/30 for desiccators
• CPC Class Codes: B65D 53/06 Sealings formed by liquid or plastic material

Abstract

A container closure comprising a container closure shell and a resin liner applied to the inner surface side of the shell, wherein the resin liner is constituted by an upper layer portion which is composed of a resin composition containing such additives as disoxidation agent, drying agent, deodorant, antibacterial agent and thermo color agent and which forms a panel portion on the inside of the hermetically sealing portion, a lower layer portion which is composed of a thermoplastic resin having cushioning property and elasticity and which is interposed between the upper layer portion and the top surface of the shell to join them together, and a hermetically sealing portion which is formed on the outer peripheral side of the panel portion integrally with the lower layer portion. There is further provided a container closure with liner of the function separation type which is free from defects inherent in the conventional function addition-type container closures with liner, and which permits additional functions to be exhibited to a high degree without impairing hermetically sealing property, and a method of producing the same. Moreover, there is provided a method of producing the container closure with liner of the function separation type maintaining excellent produceability and high quality.

Claims

1. A container closure with a liner comprising a container closure shell and a liner of resin applied to an inner surface of said shell, wherein the liner of resin comprises (i) an upper layer portion which forms a panel, (ii) a lower layer portion which is interposed between said upper layer portion and the shell to join them together and (iii) an outer peripheral portion which forms a hermetically sealing portion, said upper layer portion (i) comprises a resin composition (A) containing additives selected from the group consisting of an oxygen absorbing agent, a drying agent, a deodorant, an antibacterial agent and a thermal color agent, and said lower layer portion (ii) and said outer peripheral portion (iii) are integrally formed and comprise a thermoplastic resin (B) with a cushioning property and elasticity and being free of said additives, said liner being formed by press-molding a molten mass of resin (B) and placing the panel of resin composition (A) onto the molten mass in the container closure shell.

2. A container closure with liner according to claim 1, wherein a fine roughness is formed on the surface of said panel portion at the side of the container.

3. A container closure with a liner according to claim 1, wherein said hermetically sealing portion and said lower layer portion comprise a blend of a low-density polyethylene with at least one of (a) an ethylene-propylene copolymer and (b) a thermoplastic elastomer in an amount of 3 to 40% by weight.

4. A container closure with a liner according to claim 1, wherein said panel portion is provided with a thin coating layer for preventing the elution of said additives.