Closure for a product retaining container

Abstract

A closure for a product retaining container constructed for being inserted and securely retained in a portal forming neck of the container has a substantially cylindrical shape and substantially flat terminating surfaces forming the opposed ends of said closure, wherein at least one of said terminating surfaces is at least partially covered by a decorative layer. Indicia may be applied on at least one of the two substantially flat terminating surfaces forming the opposed ends of a closure by means of hot stamping.

Claims

1. A closure for a product retaining container constructed for being inserted and securely retained in a portal forming neck of the container with the closure being in direct fluid communication with a fluid product within the product retaining container, the closure comprising: a substantially cylindrical shape comprising a length; substantially flat terminating surfaces forming opposed ends of said closure and defining a gas permeation property of the closure corresponding to a gas permeation rate through the opposed ends of the closure when the closure is disposed in the portal forming neck of the container; and a decorative layer only partially covering at least one of said terminating surfaces such that the gas permeation property of the closure is not significantly altered by presence of the decorative layer, the decorative layer comprising a plastic material and being compositionally different from a material of said terminating surfaces; wherein in use the entire length of the closure fits into the portal forming neck of the container without the closure extending beyond a lateral width of the portal forming neck of the container.

2. The closure of claim 1, wherein said decorative layer is applied to said terminating surfaces by means of heat transfer, pressure transfer and/or hot stamping.

3. The closure of claim 1, wherein said decorative layer comprises a first color; wherein said terminating surfaces comprise a second color; and wherein the first color differs from the second color.

4. The closure of claim 1, wherein said decorative layer comprises at least one plastic film.

5. The closure of claim 1, wherein said decorative layer comprises a polyester.

6. The closure of claim 1, wherein said decorative layer comprises a pigment or dye.

7. The closure of claim 1, further comprising a hot melt adhesive affixing said decorative layer to said at least one of said terminating surfaces.

8. The closure of claim 1, wherein said decorative layer comprises one or more materials that are compliant or approved as food contact substances (FCS) by the U.S. Food and Drug Administration (FDA) or the European Union (EU).

9. The closure of claim 1, wherein said decorative layer comprises a thickness of 0.5 microns to 100 microns.

10. The closure of claim 1, wherein said decorative layer forms an indicia.

11. The closure of claim 10, wherein said indicia comprises one or more indicia selected from the group consisting of letters, symbols, colors, graphics, and wood tones.

12. The closure of claim 1, wherein a surface of said decorative layer is in complete, intimate, bonded engagement with said at least one of said terminating surfaces.

13. The closure of claim 1, wherein said closure comprises a synthetic closure.

14. The closure of claim 13, wherein said closure comprises one or more thermoplastic polymers.

15. The closure of claim 1, wherein said closure comprises pieces of natural cork.

16. The closure of claim 15, wherein said pieces of natural cork are agglomerated by an adhesive or embedded in a plastic material.

17. The closure of claim 1, wherein said closure is wholly or partially formed of a foamed material.

18. The closure of claim 17, wherein a cell size and/or cell distribution in the foamed material are substantially uniform throughout an entire length and/or diameter of the foamed material.

19. The closure of claim 17, wherein the foamed material comprises a substantially closed cell foam.

20. The closure of claim 17, wherein the foamed material comprises a cell size characterized by a range of between about 0.025 mm minimum and about 0.5 mm maximum.

21. The closure of claim 1, further comprising a silicone layer positioned on at least one surface.

22. A closure for a product retaining container constructed for being inserted and securely retained in a portal forming neck of the container with the closure being in direct fluid communication with a fluid product within the product retaining container, the closure comprising: an elongated, cylindrically shaped core member formed from foamed plastic material and comprising terminating end surfaces forming opposed ends of the cylindrically shaped core member, wherein the terminating end surfaces define a gas permeation property of the closure corresponding to a gas permeation rate through the opposed ends of the core member when the closure is disposed in the portal forming neck of the container; a decorative layer only partially covering at least one terminating end surface such that the gas permeation property of the closure is not significantly altered by presence of the decorative layer, the decorative layer comprising a plastic material and being compositionally different from a material of the at least one terminating end surface; and at least one peripheral layer peripherally surrounding and intimately bonded to the cylindrically shaped core member with the at least one terminating end surface of the core member being devoid of said at least one peripheral layer; wherein the closure comprises a length, and in use the entire length of the closure fits into the portal forming neck of the container without the closure extending beyond a lateral width of the portal forming neck of the container; and wherein the closure is adapted to seal the fluid product in the container for a desired length of time without substantially any degradation of the product or degradation of the closure.

23. The closure of claim 22, wherein the core member comprises at least one thermoplastic polymer selected from the group consisting of polyethylenes, metallocene catalyst polyethylenes, polybutanes, polybutylenes, polyurethanes, silicones, vinyl-based resins, thermoplastic elastomers, polyesters, ethylenic acrylic copolymers, ethylene-vinyl-acetate copolymers, ethylene-methyl-acrylate copolymers, thermoplastic polyurethanes, thermoplastic olefins, thermoplastic vulcanizates, flexible polyolefins, fluorelastomers, fluoropolymers, polyethylenes, polytetrafluoroethylenes, and blends thereof, ethylene-butyl-acrylate copolymers, ethylene-propylene-rubber, styrene butadiene rubber, styrene butadiene block copolymers, ethylene-ethyl-acrylic copolymers, ionomers, polypropylenes, and copolymers of polypropylene and copolymerizable ethylenically unsaturated comonomers, olefin block copolymers and mixtures thereof.

24. The closure of claim 22, wherein said core member comprises a density ranging between about 100 kg/m.sup.3 to about 500 kg/m.sup.3.

25. The closure of claim 22, wherein said core member comprises a density ranging between about 200 kg/m.sup.3 to about 350 kg/m.sup.3.

26. The closure of claim 22, wherein said core member comprises closed cells having an average cell size ranging from between about 0.02 mm to about 0.50 mm and/or a cell density ranging between about 8,000 cells/cm.sup.3 to about 25,000,000 cells/cm.sup.3.

27. The closure of claim 26, wherein said core member comprises an average cell size ranging between about 0.05 mm and 0.1 mm and/or a cell density ranging between about 1,000,000 cells/cm.sup.3 to about 8,000,000 cells/cm.sup.3.

28. The closure of claim 22, wherein said at least one peripheral layer is selected from the group consisting of foamed plastics and non-foamed plastics.

29. The closure of claim 22, wherein said at least one peripheral layer is selected from the group consisting of foamable or non-foamable thermoplastic polyurethanes, thermoplastic olefins, thermoplastic vulcanizates, EPDM rubber, flexible polyolefins, fluoroelastomers, fluoropolymers, polyethylenes, polytetrafluoroethylenes, olefin block copolymers, and blends thereof.

30. The closure of claim 22, wherein said at least one peripheral layer comprises a thickness ranging between about 0.05 mm and about 5 mm.

31. The closure of claim 22, wherein said at least one peripheral layer comprises a thickness ranging between about 0.1 mm and about 2 mm.

32. The closure of claim 22, wherein said at least one peripheral layer comprises a tough, score and mar resistant surface and/or a density ranging between about 300 kg/m.sup.3 and 1,500 kg/m.sup.3.

33. The closure of claim 22, wherein said at least one peripheral layer comprises a density between about 750 kg/m.sup.3 and about 1100 kg/m.sup.3.

34. The closure of claim 22, wherein said closure is further defined as being formed by extrusion and/or injection molding.

35. The closure of claim 22, wherein said core member comprises an extruded core member.

36. The closure of claim 22, wherein said core member and said at least one peripheral layer are further defined as being extruded simultaneously.

37. The closure of claim 22, wherein said core member is further defined as being extruded separately and subsequent thereto said at least one peripheral layer is formed in extrusion equipment peripherally surrounding and enveloping the core member.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) For a fuller understanding of the nature and objects of the invention herein described, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

(2) FIG. 1 is a perspective view of a synthetic closure according to an embodiment of the present disclosure;

(3) FIG. 2 is a cross sectional-side elevation of a synthetic closure according to an embodiment of the present disclosure;

(4) FIG. 3 is a perspective view of a stamping tool suitable for use in the method according to the present disclosure;

(5) FIG. 4 is a cross-sectional side elevation of a synthetic closure, a stamping foil and a stamping tool suitable for use in the method according to the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(6) By referring to FIGS. 1 to 4, along with the following detailed disclosure, the construction and production method for the closures of the present disclosure can best be understood. In these Figures, as well as in the following detailed disclosure, the synthetic closure of the present disclosure, and its method of production, is depicted and discussed as a bottle closure for wine products. However, as detailed above, the present disclosure is applicable as a synthetic closure for use in sealing and retaining any desired product in any desired closure system. However, due to the stringent and difficult demands and requirements placed upon closures for wine products, the following detailed disclosure focuses upon the applicability of the synthetic bottle closures of the present disclosure as a closure for wine bottles. However, it is to be understood that this detailed discussion is provided merely for exemplary purposes and is not intended to limit the present disclosure to this particular application and embodiment.

(7) In FIG. 1, an exemplary construction of a synthetic closure 20 is depicted comprising a generally cylindrical shape formed by core member 22 and outer layer or skin layer 24 which peripherally surrounds and is intimately bonded to core member 22. In an exemplary embodiment, core member 22 comprises a substantially cylindrically shaped surface 26, terminating with substantially flat end surfaces 27 and 28. Parts of the substantially flat end surface 27 are covered by a decorative layer 29 forming the number 2009 and a circle. It should be appreciated that the closures of the present disclosure are not restricted to such layered products. It should be noted, however, that the synthetic closure of the present disclosure may also comprise only one single component (e.g. a foamed, partially foamed or unfoamed cylindrically shaped body made from thermoplastic material) without any additional layers. Whenever applicable, the following detailed description of a synthetic closure having a layered structure (i.e. a core member and at least one outer layer) shall also apply to such single component synthetic closures.

(8) In an exemplary embodiment, outer layer or skin layer 24 is intimately bonded directly to core member 22, peripherally surrounding and enveloping surface 26 of core member 22. Outer layer or skin layer 24 incorporates exposed surface 29, which comprises a substantially cylindrical shape and forms the outer surface of synthetic bottle closure 20 of the present disclosure, along with flat end of surfaces 27 and 28.

(9) In order to assist in assuring entry of synthetic bottle closure 20 into the portal of the bottle into which closure 20 is inserted, the terminating edge of peripheral layer 24 may be beveled or chamfered (not depicted). Similarly, the terminating edge of peripheral layer 24 also may comprise a similar bevel or chamfer (not depicted). Although any desired bevel or chamfered configuration can be employed, such as a radius, curve, or flat surface, it has been found that merely cutting the ends with an angle of about 45, the desired reduced diameter area is provided for achieving the desired effect.

(10) By incorporating chamfered or beveled ends on synthetic bottle closure 20, automatic self-centering is attained. As a result, when synthetic bottle closure 20 is compressed and ejected from the compression jaws into the open bottle for forming the closure thereof, synthetic bottle closure 20 is automatically guided into the bottle opening, even if the clamping jaws are slightly misaligned with the portal of the bottle. By employing this configuration, unwanted difficulties in inserting bottle closure 20 into any desired bottle are obviated. However, in applications which employ alternate stopper insertion techniques, chamfering of ends may not be needed. Further, in order to facilitate the insertion of the closure into the bottle neck, the outer surface can fully or partly be coated with suitable lubricants, in particular with silicones.

(11) In order to produce the attributes required for use in the wine industry, core 22 is formed from foam plastic material using a continuous extrusion process. Although other prior art systems have employed molded foamed plastic material, these processes have proven to be more costly and incapable of providing a final product with the attributes of the present disclosure.

(12) In an exemplary embodiment, core member 22 is formed as an extruded, medium or low density closed cell foamed plastic comprising one or more plastics selected from the group consisting of inert polymers, homopolymers, and copolymers.

(13) The thermoplastic polymer may be selected from the group consisting of polyethylenes, metallocene catalyst polyethylenes, polybutanes, polybutylenes, polyurethanes, silicones, vinyl based resins, thermoplastic elastomer, polyesters, ethylene acrylic copolymers, ethylene-vinyl-acetate copolymers, ethylene-methyl acrylate copolymers, ethylene-butyl-acrylate copolymers, ethylene-propylene-rubber, styrene butadiene rubber, styrene butadiene block copolymers, styrene block copolymers, ethylene-ethyl-acrylic copolymers, ionomers, polypropylenes, and copolymers of polypropylene and copolymerizable ethylenically unsaturated commoners, as well as ethylenic acrylic copolymers, ethylene-vinyl-acetate copolymers, ethylene-methyl-acrylate copolymers, thermoplastic polyurethanes, thermoplastic olefins, olefin block copolymers, thermoplastic vulcanizates, flexible polyolefins, fluoroelastomers, fluoropolymers, polyethylenes, teflons (polytetrafluoroethylenes), ethylene-butyl-acrylate copolymers, ethylene-propylene-rubber, ethylene-ethyl-acrylic copolymers and blends thereof. Furthermore, if a polyethylene is employed, it has been found that the polyethylene may comprise one or more polyethylenes selected from the group consisting of high density, medium density, low density, linear low density, ultra high density, and medium low density.

(14) More particularly, the thermoplastic polymer may be selected from the group consisting of polyethylenes, metallocene catalyst polyethylenes, polybutanes, polybutylenes, polyurethanes, silicones, vinyl/based resins, thermoplastic elastomers, polyesters, ethylenic acrylic copolymers, ethylene-vinyl-acetate copolymers, ethylene-methyl-acrylate copolymers, thermoplastic polyurethanes, thermoplastic olefins, thermoplastic vulcanizates, flexible polyolefins, fluoroelastomers, fluoropolymers, polyethylenes, polytetrafluoroethylenes, and blends thereof, ethylene-butyl-acrylate copolymers, ethylene-propylene-rubber, styrene butadiene rubber, styrene butadiene block copolymers, styrene block copolymers, ethylene-ethyl-acrylic copolymers, ionomers, polypropylenes, and copolymers, ionomers, polypropylenes, and copolymers of polypropylene and copolymerizable ethylenically unsaturated comonomers, olefin block polymers, and mixtures thereof.

(15) Regardless of the foamable plastic material selected for forming core member 22, the resulting extruded foam product may have a density ranging between about 100 kg/m.sup.3 to 500 kg/m.sup.3. Although this density range has been found to provide an effective core member, the density of the extruded foam core member 20 preferably ranges between about 200 kg/m.sup.3 to 350 kg/m.sup.3. In another embodiment, the resulting extruded foam product may have a density ranging between about 100 kg/m.sup.3 to 600 kg/m.sup.3. Although this density range has been found to provide an effective core member, the density of the extruded foam core member 20 preferably ranges between about 200 kg/m.sup.3 to 400 kg/m.sup.3.

(16) Since core member 22 is substantially closed cell in structure, additives can intermixed with the plastic material to form a closed cell foam. The resulting core member 22 of the present disclosure may have average cell sizes ranging from between about 0.02 millimeters to 0.50 millimeters and/or a cell density ranging between about 25,000,000 cells/cm.sup.3 to 8,000 cells/cm.sup.3. Although this cell configuration has been found to produce a highly effective product, it has been found that the most desirable product possesses an average cell size ranging between about 0.05 and 0.1 millimeters with a cell density ranging between about 8,000,000 cells/cm.sup.3 to 1,000,000 cells/cm.sup.3. In another embodiment, an average cell size ranges between about 0.05 and 0.3 millimeters. Furthermore, in order to assure that core member 22 possesses inherent consistency, stability, functionality and capability of providing long-term performance, the cell size of core member 22 may be homogeneous throughout its entire length and diameter. According to an exemplary embodiment of the disclosure, the foam has a cell size characterized by a range of between about 0.025 mm minimum and about 0.5 mm maximum, in particular between about 0.05 mm minimum to about 0.35 mm maximum.

(17) In order to control the cell size of core member 22 and attain the desired cell size detailed above, a nucleating agent can be employed. It has been found that by employing a nucleating agent selected from the group consisting of calcium silicate, talc, clay, titanium oxide, silica, barium sulfate, diatomaceous earth, and mixtures of citric acid and sodium bicarbonate, the desired cell density and cell size is achieved.

(18) In this regard, it has been found that cell size and cell density is most advantageously realized in the formation of core member 22 by employing between about 0.1 and 10 parts by weight of the nucleating agent for every 100 parts by weight of the plastic foam. In this way, the desired physical characteristics of core member 22 are realized along with the desired control of the cell size and cell density. This leads to product consistency currently not available with natural materials.

(19) As is well known in the industry, a blowing agent can be employed in forming extruded foam plastic material. In the present disclosure, a variety of blowing agents can be employed during the extruded foaming process whereby core member 22 is produced. Typically, either physical blowing agents or chemical blowing agents are employed. Suitable blowing agents that have been found to be efficacious in producing the core member of the present disclosure comprise one or more selected from the group consisting of: aliphatic hydrocarbons having 1-9 carbon atoms, halogenated aliphatic hydrocarbons having 1-9 carbon atoms and aliphatic alcohols having 1-3 carbon atoms. Aliphatic hydrocarbons include methane, ethane, propane, n-butane, isobutane, n-pentane, isopentane, neopentane, and the like. Among halogenated hydrocarbons and fluorinated hydrocarbons they include, for example, methylfluoride, perfluoromethane, ethyl fluoride, 1,1-difluoroethane (HFC-152a), 1,1,1-trifluoroethane (HFC-430a), 1,1,1,2-tetrafluoroethane (HFC-134a), pentafluoroethane, perfluoroethane, 2,2-difluoropropane, 1,1,1-trifluoropropane, perfluoropropane, perfluorobutane, perfluorocyclobutane. Partially hydrogenated chlorocarbon and chlorofluorocarbons for use in this disclosure include methyl chloride, methylene chloride, ethyl chloride, 1,1,1-trichlorethane, 1,1-dichloro1-fluoroethane (HCFC-141b), 1-chloro1,1-difluoroethane (HCFC-142b), 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123) and 1-chloro-1,2,2,2-tetrafluoroethane (HCFC-124). Fully halogenated chlorofluorocarbons include trichloromonofluoromenthane (CFC11), dichlorodifluoromenthane (CFC-12), trichlorotrifluoroethane (CFC-113), dichlorotetrafluoroethane (CFC-114), chloroheptafluoropropane, and dichlorohexafluoropropane. Fully halogenated chlorofluorocarbons are not preferred due to their ozone depiction potential. Aliphatic alcohols include methanol, ethanol, n-propanol and isopropanol. Suitable inorganic blowing agents useful in making the foam of the present disclosure include carbon dioxide, nitrogen, carbon, water, air, nitrogen, helium, and argon.

(20) Chemical blowing agents include azodicarbonamide, azodiisobutyro-nitride, benzenesulfonhydrazide, 4,4-oxybenzene sulfonylsemicarbazide, p-toluene sulfonylsemicarbazide, barium azodicarboxlyate, N,N-Dimethyl-N,N-dinitrosoterephthalamide, trihydrazinotriazine, and hydrocerol.

(21) To produce the desired product, the blowing agent is incorporated into the plastic melt in a quantity ranging between about 0.005% to 10% by weight of the weight of the plastic material.

(22) As detailed above, either a physical blowing agent or a chemical blowing agent can be employed as part of the manufacturing process for forming core member 22 of the present disclosure. However, it has been found that the selection of a physical blowing agent is appropriate since physical blowing agents allow core member 22 of synthetic bottle closure 20 to be achieved with a lower density, which is closer to natural cork.

(23) In this regard, a blowing agent which is inert is particularly contemplated. Although any desired inert blowing agent may be employed, the blowing agent may be selected from the group consisting of nitrogen, carbon dioxide, sulphur dioxide, water, air, nitrogen, helium, and argon. In addition, hydrocarbons can be employed as the blowing agent which may be selected from the group consisting of butane, isobutene, pentane, isopentane and propane.

(24) In addition to attaining core member 22 which possesses a construction with physical characteristics similar to nature cork, the synthetic bottle closure 20 of the present disclosure can also comprise a peripheral layer 24. The peripheral layer 24 is of particular importance in attaining synthetic bottle closure 20 which is capable of meeting and exceeding all of the difficult requirements imposed upon a closure or stopper for the wine industry.

(25) As discussed above, the wine industry incorporates corking machines which incorporate a plurality of cooperating, movable jaws which move simultaneously to compress the bottle stopper to a diameter substantially smaller than the diameter of the portal into which the stopper is inserted. Then, once fully compressed, the stopper is forced out of the jaws directly into the bottle, for expanding and immediately closing and sealing the bottle.

(26) Due to the operation of the cooperating jaws which are employed to compress the stopper for insertion into the bottle, sharp edges of the jaw members are forced into intimate contact with the outer surface of the stopper. Although cork material has been successful in resisting permanent damage from the jaw edges in most instances, other prior art synthetic stoppers have been incapable of resisting these cutting forces. As a result, longitudinal cuts, score lines or slits are formed in the outer surface of the stopper, enabling liquid to seep from the interior to the exterior of the bottle.

(27) This inherent problem, existing with prior art cork and synthetic closures, can be eliminated by incorporating peripheral layer 24 which surrounds and envelopes substantially the entire outer surface 26 of core member 22. In addition, by forming peripheral layer 24 from high density, rugged, score-resistant material, synthetic bottle closure 20 overcomes all of the prior art difficulties and achieves a bottle closure having physical properties equal to or superior to conventional cork material.

(28) In an exemplary embodiment, peripheral layer 24 is formed from plastic material identical or similar to the plastic material employed for core member 22. However, as detailed below, the physical characteristics imparted to peripheral layer 24 differ substantially from the physical characteristics of core member 22.

(29) In a particularly contemplated construction, peripheral layer 24 has a thickness ranging between about 0.05 and 5 millimeters and, more preferably, between about 0.1 and 2 millimeters. Although these ranges have been found to be efficacious to producing synthetic bottle closure 20 which is completely functional and achieves all of the desired goals, an exemplary embodiment for wine bottles comprises a thickness of between about 0.1 and 1 millimeter.

(30) In producing peripheral layer 24 and achieving the desired tough, score and mar-resistant surface for core member 22, peripheral layer 24 may comprise a density ranging between about 300 kg/m.sup.3 to 1,500 kg/m.sup.3. In particularly contemplated embodiments, it has been found that the density of peripheral layer 24 ranges between about 750 kg/m.sup.3 to 1100 kg/m.sup.3.

(31) In accordance with the present disclosure, the synthetic bottle closure 20 of the present disclosure should be formed with peripheral layer 24 intimately bonded to substantially the entire surface 26 of core member 22. If any large unbonded areas exist, flow paths for gas and liquid could result. Consequently, secure, intimate, bonded interengagement of peripheral layer 24 with core member 22 is required for attaining a bottle closure for the wine industry.

(32) In order to achieve this integral bonded interconnection between peripheral layer 24 and core member 22, peripheral layer 24 is formed about core member 22 in a manner which assures intimate bonded engagement. The desired secure, intimate, bonded, interengagement may be attained by simultaneous co-extrusion of core member 22 and peripheral layer 24 or by applying peripheral layer 24 to core member 22 after core member 22 has been formed. By employing either process, intimate bonded interengagement of peripheral layer 24 to core member 22 is attained.

(33) By using equipment well known in this industry, the synthetic bottle closure 20 of the present disclosure can be produced by co-extruding core member 22 simultaneously with peripheral layer 24 to provide a final product wherein peripheral layer 24 is intimately bonded to core member 22 in a single, continuous operation. If co-extrusion process is employed, once the continuous elongated co-extruded layers forming synthetic bottle closure 20 have been completely formed and are ready for final processing, the elongated dual component material produced is cut to the precise length desired for forming synthetic bottle closures 20.

(34) After each bottle closure 20 has been formed with the desired length, the desired chamfer, if needed, is formed at each end of peripheral layer 24 in order to provide the benefits detailed above. Once the chamfer or radius has been achieved, synthetic bottle closure 20 is ready for distribution to the desired consumer, unless appropriate coatings and/or printing will be applied. Closure 20 may be coated with a suitable lubricant (e.g. silicone coating) before distribution to the desired consumer.

(35) In the alternate construction, core member 22 is formed as an elongated, continuous, extruded foam product and is cooled or allowed to cool until ready for subsequent processing. Then, whenever desired, the continuous elongated length forming core member 22 is fed through a cross-head machine which enables peripheral layer 24 to be formed and positioned in the desired location peripherally surrounding core member 22 in intimate bonded interengagement therewith. Once the dual component product has been completed, the elongated length of material is cut to the desired length for forming bottle closure 20, as detailed above, with the desired chamfer or radius being formed in peripheral layer 24, attaining the final product.

(36) In a further alternate embodiment, synthetic bottle closure 20 of the present disclosure is formed by employing generally conventional injection molding techniques. As is well known, injection molding is a manufacturing process where plastic is forced into a mold cavity under pressure. The mold cavity is essentially a negative of the part being produced, and the cavity is filled with plastic, and the plastic changes phase to a solid, resulting in a positive. Typically, injection pressures range from 5,000 to 20,000 psi. Because of the high pressures involved, the mold must be clamped shut during injection and cooling.

(37) By employing this process, a plurality of separate and independent bottle closures 20 can be simultaneously formed in a multi-cavity mold having the precisely desired shape and configuration. Consequently, if beveled or chamfered edges are desired, the desired configuration is incorporated into the mold, thereby producing a product with the final shaped desired.

(38) Typically, injection molding is employed to produce products having a single composition. However, if desired core member 22 may be formed with outer peripheral layer 24 surrounding and intimately bonded thereto using alternate techniques such as multi-step molding and multi-component molds, or subsequent coating operations, such as spray coating, tumble coating, or immersion coating. By employing these procedures, synthetic bottle closures 20 of the present disclosure are formed in an injection molding process, as desired, achieving the unique synthetic bottle closure of the present disclosure.

(39) As discussed above, intimate bonded interengagement of peripheral layer 24 to core member 22 is required for providing a synthetic bottle closure 20 capable of being used in the wine industry. In this regard, although it has been found that the processes detailed above provide secure intimate bonded interengagement of peripheral layer 24 to core member 22, alternate layers or bonding chemicals can be employed, depending upon the particular materials used for forming core member 22 and peripheral layer 24.

(40) If desired, well known bonding agents or tie layers can be employed on the outer surface of core member 22 in order to provide secure intimate bonded interengagement of peripheral layer 24 therewith. If a tie layer is employed, the tie layer would effectively be interposed between core member 22 and peripheral layer 24 to provide intimate bonded interengagement by effectively bonding peripheral layer 24 and core member 22 to the intermediately positioned tie layer. However, regardless of which process or bonding procedure is employed, all of these alternate embodiments are within the scope of the present disclosure.

(41) As detailed above, a wide variety of plastic materials can be employed to produce the extruded synthetic bottle closure 20 of the present disclosure. Although each of the plastic materials detailed herein can be employed for both core member 22 and peripheral layer 24, an exemplary plastic material for forming both core member 22 and peripheral layer 24 comprises one or more selected from the group consisting of medium density polyethylenes, low density polyethylenes, metallocene catalyst polyethylenes, polypropylenes, polyesters, ethylene-butyl-acrylate copolymers, vinyl-acetate copolymers, ethylene-methyl acrylate copolymers, styrene block copolymers, olefin block copolymers, and blends of these compounds.

(42) It has also been discovered that the outer peripheral layer or skin layer 24 may comprise a thermoplastic composition which differs from the thermoplastic composition employed for the core member. In this regard, the outer peripheral layer 24 may comprise one or more selected from the group consisting of foamable or non-foamable thermoplastic polyurethanes, thermoplastic olefins, styrene block copolymers, olefin block copolymers, thermoplastic vulcanizates, flexible polyolefins, fluoroelastomers, fluoro-polymers, polyethylenes, Teflons, and blends thereof. In addition, peripheral layer 24 may be formed from thermoplastic olefinic elastomers such as petrothene TPOE, thermoplastic urethanes, thermoplastic polyesters, and other similar product formulas.

(43) The particular composition employed for peripheral layer 24 is selected to withstand the compression forces imposed thereon by the jaws of the corking machine. However, many different polymers, as detailed above, are able to withstand these forces and, as a result, can be employed for peripheral layer 24.

(44) In order to form synthetic bottle closure 20 with all of the desirable inherent physical and chemical properties detailed above, one compound that has been found to be most advantageous to employ for outer peripheral layer 24 is metallocene catalyst polyethylene. As detailed below, outer peripheral layer 24 may comprise 100% metallocene catalyst polyethylene or, if desired, the metallocene catalyst polyethylene may be intermixed with a polyethylene. In this regard, it has been found that outer peripheral layer 24 may comprise between about 25% and 100% by weight based upon the weight of the entire composition of one or more polyethylenes selected from the group consisting of medium density polyethylenes, medium low density polyethylenes, and low density polyethylenes.

(45) A formulation which has been found to be highly effective in providing an outer peripheral layer 24 is metallocene catalyst polyethylene.

(46) Another formulation which has been found to be highly effective in providing an outer peripheral layer 24 is a thermoplastic vulcanizate.

(47) Another formulation which has been found to be highly effective in providing an outer peripheral layer 24 which meets all of the required physical and chemical attributes to attain a commercially viable synthetic bottle closure 20 is a polyether-type thermoplastic polyurethane and/or olefin block copolymer or blends thereof.

(48) By employing this material and forming the material in peripheral, surrounding, bonded engagement with any desired foamed core member 22, a highly effective, multi-layer synthetic closure is attained which is able to meet and exceed all requirements for a wine bottle closure.

(49) In the construction of this embodiment, the particular polyether-type thermoplastic polyurethane employed for forming outer peripheral layer 24 comprises Elastollan LP9162, manufactured by BASF Corporation of Wyandotte, Mich. (US). As detailed below in the test data provided, this compound has been found to produce an outer layer in combination with core member 22 which provides all of the physical and chemical characteristics required for attaining a highly effective synthetic closure 20 for the wine industry.

(50) In another embodiment of the present disclosure, the outer peripheral layer comprises thermoplastic vulcanizates (TPV). Such thermoplastic vulcanizates are well known in the art and are commercially available, for example, under the tradename Santoprene from ExxonMobil Chemical Company of Houston, Tex. (US), Sarlink and Uniprene from Teknor Apex Company (US) or OnFlex from PolyOne Inc. of Avon Lake, Ohio (US).

(51) In addition to employing the polyether-type thermoplastic polyurethane detailed above, another compound that has been found to be highly effective in providing all of the desirable attributes required for outer peripheral layer 24 is a blend of thermoplastic olefins and thermoplastic vulcanizates. In an exemplary embodiment, the blend of thermoplastic olefins and thermoplastic vulcanizates comprises between about 100% and 90% by weight based upon the weight of the entire composition of the thermoplastic olefin and between about 100% and 90% by weight based upon the weight of the entire composition of the thermoplastic vulcanizate. As detailed below in the test data, the construction of synthetic closure 20 using an outer peripheral surface 24 formed from this blend provides a wine bottle closure which exceeds all requirements imposed thereon.

(52) Another compound that has also been found to provide a highly effective outer peripheral layer 24 for synthetic closure 20 of the present disclosure comprises flexible polyolefins manufactured by Huntsman Corporation of Salt Lake City, Utah. These compounds are sold under the trademark REXflex FPO, and comprise homogeneous reactor-synthesized polymers, produced under proprietary technology which attains polymers having unique combinations of properties.

(53) In a further alternate embodiment, a highly effective synthetic bottle closure 20 is attained by employing metallocene catalyst polyethylenes and/or olefin block copolymers, either independently or in combination with one selected from the group consisting of low density polyethylenes, medium density polyethylenes, and medium low density polyethylenes. In this embodiment, these materials may be employed for both core member 22 and peripheral layer 24.

(54) Still further additional compounds which have been found to provide highly effective outer peripheral surfaces 24 for forming synthetic bottle closures 20, in accordance with the present disclosure, comprise teflon, fluoroelastomeric compounds and fluoropolymers. These compounds, whether employed individually or in combination with each other or with the other compounds detailed above have been found to be highly effective in producing an outer peripheral layer 24 which is capable of satisfying all of the inherent requirements for synthetic bottle closure 20.

(55) Any of the compounds detailed herein for providing outer peripheral layer 24 can be employed using the extrusion processes detailed above to produce an outer layer which is securely and integrally bonded to core member 22, either as a foamed outer layer or a non-foamed outer layer. In addition, these compounds may also be employed using the molding processes detailed above to produce the desired synthetic bottle closure 20 of the present disclosure.

(56) In addition, it has also been found that additives may be incorporated into outer peripheral layer 24 in order to further enhance the performance of the resulting synthetic bottle closure 20. As detailed above, these additional additives include slip resistant additives, lubricating agents, and sealing compounds.

(57) It has also been discovered that further additional additives may be incorporated into either core member 22 and/or outer layer 24 of synthetic closure 20 in order to provide further enhancements and desirable performance characteristics. These additional additives incorporate antimicrobial agents, antibacterial compounds, and or oxygen scavenging materials. Suitable oxygen scavenging additives include, for example, sodium ascorbate, sodium sulfite, edetate dipotassium (dipotassium EDTA), hydroquinone, and similar substances are used to actively bind free oxygen. Oxygen scavenging additives are known in the art and are commercially available, for example, under the tradename Shelfplus O2 from Ciba AG at Basel (CH).

(58) The antimicrobial and antibacterial additives can be incorporated into the present disclosure to impart an additional degree of confidence that in the presence of a liquid the potential for microbial or bacterial growth is extremely remote. These additives have a long-term time release ability and further increase the shelf life without further treatments by those involved with the bottling of wine. This technology has been shown to produce short as well as long term results (microbial and bacterial kills in as little as ten minutes with the long term effectiveness lasting for tens of years) which cannot be achieved with a natural product.

(59) By employing any desired combination of these agents or additives, a further enhanced synthetic closure is realized which is capable of providing a product performance which has heretofore been incapable of being provided by either cork closures or conventional synthetic closures.

(60) In order to attain the desired chemical and physical properties for the synthetic closure 20, core member 22 can comprise between about 0% and 75% by weight of metallocene catalyst polyethylene, and between about 25% and 100% by weight of one or more polyethylenes as detailed above. In forming peripheral layer 24 in secure, bonded interengagement therewith, it has been found that any of the formulations detailed above may be employed, with the selected formulations being affixed to core member 22 by co-extrusion or cross-head extrusion methods.

(61) As described hereinbefore, the method of applying indicia 29 on at least one of the two substantially flat terminating surfaces 27, 28 of the closure 20 comprises the following steps: A. providing a stamping foil 50 comprising at least a carrier film and a decorative layer; B. providing a stamping tool 40 that is patterned so as to form a negative image of indicia 29 by raised regions 45 on the surface of stamping tool 40; C. placing stamping foil 50 on top of or slightly above said terminating surface 27 of closure 20 with said decorative layer facing towards flat terminating surface 27, whereby flat terminating surface 27 is at least partially covered by stamping foil 50; D. pressing stamping foil 50 against terminating surface 27 of closure 20 by means of stamping tool 40 under application of heat and/or pressure, whereby those portions of the decorative layer that have been in contact with raised regions 45 of stamping tool 40 are being transferred from the stamping foil 50 and permanently affixed to terminating surface 27 of closure 20, thereby forming the desired indicia 29 on terminating surface 27 of closure 20; and E. removing the used stamping foil 50, thereby uncovering indicia 29 formed on terminating surface 27 of closure 20.

(62) In FIG. 3 a hot stamping tool 40 for pressing the stamping foil 50 against the terminating surface 27 of the closure 20 is depicted. The hot stamping tool 40 has raised regions 45 forming a negative image of the numbers 2009 and a circle. The hot stamping tool 40 may be made of metal and is connected to a heating unit (not depicted) and/or pressure unit (not depicted) so as to allow the hot stamping tool 40 to be heated to a desired temperature and/or applied to the terminating surface 27 of the closure 20 with the desired pressure.

(63) FIG. 4 is a schematic representation of a suitable assembly for carrying out the method according to the present disclosure. A stamping foil 50 is arranged in a position between terminating surface 27 of closure 20 and stamping tool 40, the raised portion 45 of stamping tool 40 facing in the direction of the upper surface of the stamping foil 50. The stamping foil 50 comprises at least a carrier film (not depicted) and a decorative layer 29, the decorative layer 29 of stamping foil 50 facing towards the terminating surface 27 of the closure 20. In addition to the carrier film and the decorative layer 29 the stamping foil 50 may contain further layers. In order to allow an faster throughput of the method according to the disclosure, the stamping foil 50 is movably arranged between terminating surface 27 of closure 20 and stamping tool 40 and the used stamping foil 50 can be rolled on roll 55, whereby unused stamping foil 50 is rolled off supply roll 56 for stamping of the subsequent closure 20. The raised portion 45 of stamping tool 40 is pressed against terminating surface 27 of closure 20, whereby the area of the decorative layer 29 of stamping foil 50 that has been in contact with the raised regions 45 stamping tool 40 are transferred from stamping foil 50 and permanently affixed to terminating surface 27 of closure 20, thereby forming the numbers 2009 and a circle 29 on terminating surface 27 of closure 20. Once the transfer has been completed, the used stamping foil 50 is removed from the closure, if necessary, and rolled on roll 55.

(64) In order to demonstrate the efficacy of the present disclosure, samples of synthetic bottle closures 20, manufactured in accordance with the present disclosure and having a foamed core member and a solid peripheral layer were produced and tested. These sample products were produced on conventional co-extrusion equipment. Core member 22 was produced by employing low density polyethylene (LDPE) using an inert gas as physical blowing agent. The degree of foaming was adjusted so as to produce samples having a density of approximately 240 kg/m.sup.3. In forming peripheral layer 24, a mixture of EPDM and PP and metallocene PE was employed. In the forming process, peripheral layer 24 was foamed in the extrusion equipment peripherally surrounding core member 22 and being intimately bonded thereto. The resulting products were cut in lengths suitable for forming bottle closure 20. The resulting closures had a diameter of 22.5 mm and a length of 44 mm.

(65) The sample closures were subjected to hot stamping as described in the preceding paragraph, thereby transferring the letters 2009 and a circle 29 to terminating surface 27 of closure 20. Hot stamping was effected at a temperature of approximately 120 degrees Celsius using a stamping foil 50 whose decorative layer 29 contained the following portions: (a) an adhesive layer portion having a thickness of about 0.5 to about 5 microns in one embodiment and a thickness of about 0.5 to about 20 microns in another embodiment, (b) a pigmented or colored lacquer layer portion having a thickness of about 1 to about 10 microns in one embodiment and a thickness of about 1 to about 15 microns in another embodiment, and (c) a transparent protective lacquer layer portion having a thickness of about 1 to about 10 microns in one embodiment and a thickness of about 1 to about 15 microns in another embodiment, with the adhesive layer portion (a) facing directly towards terminating surface 27 of closure 20, portion (b) being arranged on top of portion (a) and being in close interconnection therewith, and portion (c) being arranged on top of portion (b) and being in close interconnection therewith. The adhesive layer portion of the decorative layer 29 contained an adhesive having an activation temperature of approximately 110 to 115 degrees Celsius. All materials of the decorative layer 29, in particular the materials of protective layer portion (c) were compliant or approved as food contact substances (FCS) by the U.S. Food and Drug Administration (FDA) or the European Union (EU).

(66) Testing of the sample closures showed that the decorative layer 29 is securely affixed and completely bonded to surface 27 of closure 20. Moreover, contrary to previous expectations, the application of a decorative layer 29 on terminating surface 27 in accordance with the method of the disclosure does not significantly alter the gas permeation and mechanical properties of the closure.

(67) It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently obtained and, since certain changes may be made in carrying out the above method without departing from the scope of this disclosure, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. Furthermore, it should be understood that the details of the disclosure described in the foregoing detailed description are not limited to the specific embodiments shown in the drawings but are rather meant to apply to the disclosure in general as outlined in the summary and in the claims.

(68) It is also to be understood that the following claims are intended to cover all of the generic and specific features of the disclosure herein described, and all statements of the scope of the disclosure which, as a matter of language, might be said to fall there between.