Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D51/00—Closures not otherwise provided for
  • B65D51/005—Closures provided with linings or internal coatings so as to avoid contact of the closure with the contents

Definitions

• the present invention relates to containers, such as baby bottles and cups, used for drinking purposes and closures for these articles.
• a particular object in this area would be to improve sanitary conditions of containers used by children and babies for drinking purposes.
• Typical among these are, for example, plastic baby bottles and drinking cups.
• a typical baby bottle includes the bottle container itself and a closure formed by a rubber nipple and a collar of plastic material having a hole into which the nipple is inserted, with the collar being fastened to the container.
• Another typical type of such container is a plastic cup having a closure in the form of a lid with a spout, with the lid being screwed or snapped onto the cup.
• the plastic collar and the lid forming the closures are often made by injection molding.
• Bacterial growth sites also can be produced by other liquids, such as fruit juices, formula, and even water. When the user drinks liquid from the bottle or cup, the liquid can come into contact with the bacteria, which can be transferred to the user. Accordingly, it would be desirable to attempt to eliminate the growth of such bacteria on such products, that is to make the sites incapable or less capable of supporting bacterial growth.
• the present invention relates to closures of the type described above containing an inorganic antimicrobial agent, preferably a ceramic zeolite.
• the container closures such as the collar for the baby bottles and the lids for the cups, are made with the antimicrobial agent incorporated into the plastic resin used for molding the closures.
• a further object is to provide closures for baby bottle and juvenile drinking containers having an antimicrobial agent.
• Still a further object is to provide plastic closures for drinking containers containing an inorganic antimicrobial agent which reduce the possibility of establishment of bacterial growth sites.
• Fig. 1 is a perspective view of a collar for a baby bottle
• Fig. 1 A is a plan view of an insert of antimicrobial material for a baby bottle collar
• Fig. 2 is a perspective view of a drinking container and a lid therefore;
• Fig. 3 is a view of the underside of the lid of Fig 2 showing a modified version thereof.
• Fig. 3A is a cross-section of a ridge used for the underside of the lid of Fig. 3.
• Fig. 1 shows a collar 10 of the type used as a part of a closure for the open end of a baby bottle (not shown) .
• the collar 1 0 has a top wall 1 2 with a hole 14 through which the end of the nipple (not shown) is inserted.
• the collar has a depending skirt wall 1 6 with threads on the inner wall thereof which are used to fasten the collar to the bottle with the nipple inserted.
• the collar 10 is made of a plastic material such as, for example, polypropylene, by any suitable process, such as injection molding.
• the flange of the nipple is held between the top end the bottle and the top wall 1 2 of collar.
• Fig. 2 shows a portion of a conventional type of drinking cup 20 used by children.
• the cup has a threaded upper end 22 onto which the internally threaded wall 28 of a lid 30 is to be screwed.
• the lid 30 has a spout 32 which the child places in his/her mouth, tips the cup and drinks from it.
• the lids 20 also are of plastic and are typically made by injection molding.
• the lid is normally only rinsed in tap water, such that a film is present on these surfaces which can support the growth of bacteria. This is a particular problem in the spout area, which is hard to clean.
• the collar and lid components are made of material that has antimicrobial properties. It is preferred that the plastic resin used for forming the components contains an inorganic antimicrobial agent.
• a preferred inorganic antimicrobial agent that can be incorporated into a resin suitable for the products is an antibiotic zeolite.
• Suitable zeolites and a method for incorporating them into the resin is disclosed in U.S. patent 4,938,955.
• the resins can be those such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, ABS resins and others disclosed in said patent.
• the zeolite is kneaded into the resin and the composite of the resin and the zeolite are then processed, such as by injection molding, to form the articles 1 0 and 20 described above.
• the agent is available on the potential bacteria growth sites of the surfaces of the articles, including the interior of the spout 32, to prevent the growth of bacteria, such as would be caused by milk and other liquids coming into contact with it.
• antimicrobial agents are also suitable as described below and would be processed in the same manner with the resin.
• the inorganic antimicrobial agent incorporated in the resin a number of metal ions, which are inorganic materials, have been shown to possess antibiotic activity, including silver, copper, zinc, mercury, tin, lead, bismuth, cadmium, chromium and thallium ions. These antibiotic metal ions are believed to exert their effects by disrupting respiration and electron transport systems upon absorption into bacterial or fungal cells.
• Antimicrobial metal ions of silver, gold, copper and zinc, in particular, are considered safe even for in vivo use. Antimicrobial silver ions are particularly useful for in vivo use due to the fact that they are not substantially absorbed into the body.
• the inorganic antibiotic metal containing composition is an antibiotic metal salt.
• antibiotic metal salts include silver iodate, silver iodide, silver nitrate, and silver oxide. Silver nitrate is preferred. These salts are particularly quick acting, as no release from ceramic particles is necessary for antimicrobial function.
• Antibiotic zeolites are preferred. These have been prepared by replacing all or part of the ion-exchangeable ions in zeolite with ammonium ions and antibiotic metal ions, as described in U.S. Patent Nos. 4,938,958 and 4,91 1 ,898. Such zeolites have been incorporated in antibiotic resins (as shown in U.S.
• Patent Nos. 4,938,955 and 4,906,464) and polymer articles U.S. Patent No. 4,775,585).
• Polymers including the antibiotic zeolites have been used to make refrigerators, dish washers, rice cookers, plastic film, chopping boards, vacuum bottles, plastic pails, and garbage containers.
• Other materials in which antibiotic zeolites have been incorporated include flooring, wall paper, cloth, paint, napkins, plastic automobile parts, catheters, bicycles, pens, toys, sand, and concrete. Examples of such uses are described in US Patents 5,714,445; 5,697,203; 5,562,872; 5,1 80,585; 5,714,430; and 5, 102,401 .
• Antibiotic ceramic particles useful with the present invention include zeolites, hydroxy apatite, zirconium phosphates or other ion-exchange ceramics. Zeolites are preferred, and are described in the preferred embodiments referred to below. Hydroxy apatite particles containing antimicrobial metals are described, e.g., in U.S. Patent No. 5,009,898. Zirconium phosphates containing antimicrobial metals are described, e.g., in U.S. Patent Nos. 5,296,238; 5,441 ,71 7; and 5,405,644.
• Antibiotic zeolites are well-known and can be prepared for use in the present invention using known methods. These include the antibiotic zeolites disclosed, for example, in U.S. Patent Nos. 4,938,958 and 4,91 1 ,898.
• Zeolite is an aluminosilicate having a three dimensional skeletal structure that is represented by the formula: XM j /nO-Al j Oa-YSiO j -ZHjO.
• M represents an ion-exchangeable ion, generally a monovalent or divalent metal ion
• n represents the atomic valency of the (metal) ion
• X and Y represent coefficients of metal oxide and silica respectively
• Z represents the number of water of crystallization.
• zeolites examples include A-type zeolites, X-type zeolites, Y-type zeolites, T-type zeolites, high-silica zeolites, sodalite, mordenite, analcite, clinoptilolite, chabazite and erionite.
• the present invention is not restricted to use of these specific zeolites.
• These ion-exchange capacities are sufficient for the zeolites to undergo ion-exchange with ammonium and antibiotic metal ions.
• the specific surface area of preferred zeolite particles is preferably at least 1 50 m 2 /g (anhydrous zeolite as standard) and the SiO 2 /AI 2 O 3 mol ratio in the zeolite composition is preferably less than 14, more preferably less than 1 1 .
• the antibiotic metal ions used in the antibiotic zeolites should be retained on the zeolite particles through an ion-exchange reaction.
• Antibiotic metal ions which are adsorbed or attached without an ion-exchange reaction exhibit a decreased bacteriocidal effect and their antibiotic effect is not long-lasting. Nevertheless, it is advantageous for imparting quick antimicrobial action to maintain a sufficient amount of surface adsorbed metal ion.
• the antibiotic metal ions tend to be converted into their oxides, hydroxides, basic salts etc. either in the micropores or on the surfaces of the zeolite and also tend to deposit there, particularly when the concentration of metal ions in the vicinity of the zeolite surface is high. Such deposition tends to adversely affect the bactericidal properties of ion-exchanged zeolite.
• a relatively low degree of ion exchange is employed to obtain superior bactericidal properties.
• the zeolite particles retain metal ions having bactericidal properties at ion-exchangeable sites of the zeolite in an amount less than the ion-exchange saturation capacity of the zeolite.
• the zeolite employed in the present invention retains antimicrobial metal ions in an amount up to 41 % of the theoretical ion-exchange capacity of the zeolite.
• Such ion-exchanged zeolite with a relatively low degree of ion-exchange may be prepared by performing ion-exchange using a metal ion solution having a low concentration as compared with solutions conventionally used for ion exchange.
• the antibiotic metal ion is preferably present in the range of from about 0.1 to 20wt.% of the zeolite.
• the zeolite contains from 0.1 to 20wt.% of silver ions and from 0.1 to 20wt.% of copper or ⁇ zinc ions.
• ammonium ion can be contained in the zeolite at a concentration of about 20 wt.% or less of the zeolite, it is desirable to limit the content of ammonium ions to from 0.5 to 1 5 wt.%, preferably 1 .5 to 5 wt.%.
• Weight% described herein is determined for materials dried at temperatures such as 1 10°C, 250°C or 550°C as this is the temperature employed for the preferred post-manufacturing drying process.
• a preferred antibiotic zeolite is type A zeolite containing either a combination of ion-exchanged silver, zinc, and ammonium or silver and ammonium.
• One such zeolite is manufactured by Shinegawa, Inc. under the product number AW-10N and consists of 0.6% by weight of silver ion-exchanged in Type A zeolite particles having a diameter of about 2.5 ⁇ .
• Another formulation, AJ-10N consists of about 2% by weight silver ion-exchanged in Type A zeolite particles having a diameter of about 2.5 ;.
• Another formulation, AW-80 contains 0.6% by weight of silver ion-exchanged in Type A zeolite particles having a. diameter of about 1 .0 ⁇ .
• Another formulation, AJ-80N consists of about 2% by weight silver ion-exchanged in Type A zeolite particles having a diameter of about 1 .O ⁇ . These zeolites preferably contain about between 0.5% and 2.5% by weight of ion-exchanged ammonium.
• the zeolites are often obtained in master batches of low density polyethylene, polypropylene, or polystyrene, containing 20 wt.% of the zeolite.
• thermoplastic materials for forming the composite resin used to make the articles of the invention.
• the antibiotic particles are preferably present in a concentration by weight in the resin used to make the articles of from 0.01 to 10.0 wt%, more preferably from 0.01 to 8.0 wt%, and most preferably from 0.1 to 5.0 wt%.
• the antibiotic properties of the antibiotic zeolite particles of the invention may be assayed while in aqueous formulations using conventional assay techniques, including for example determining the minimum growth inhibitory concentration (MIC) with respect to a variety of bacteria, eumycetes and yeast. In such a test, the bacteria listed below may be employed: Bacillus cereus var mycoides,
• Penicillum funiculosum Candida a/bicans
• the assay for determining MIC can be carried out by smearing a solution containing bacteria for inoculation onto a plate culture medium to which a test sample of the encapsulated antibiotic zeolite particles is added in a particular concentration, followed by incubation and culturing of the plate.
• the MIC is defined as a minimum concentration thereof required for inhibiting the growth of each bacteria.
• the antibiotic zeolites are exceptionally suitable under relevant toxicity and biocompatibility standards for use in the articles and are not adversely affected or deteriorated upon being contacted by beverages such as milk and fruit juices.
• Fig. 1 A shows a product useful with a baby bottle in the form of an annular disk 50 having a central hole 52 made from the resin and antimicrobial agent mixture.
• the mixture is formed into flat sheets which are then cut or punched to the desired shape.
• the disks 50 also can be made by extrusion or other conventional processes.
• the disk 50 is inserted against the inner surface of the collar upper wall 1 4.
• the agent present in the disk performs the function of preventing bacteria growth, as explained above.
• Fig. 3 shows the inner surface 35 of the lid 30 as having a plurality of ridges 37 disposed thereon.
• the ridges 37 increase the available surface area of the antibiotic agent.
• Fig. 3A shows the ridges 37 as being of generally triangular shape, although other suitable shapes can be used.

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• 1999
  • 1999-10-25 EP EP19990955165 patent/EP1044139A4/de not_active Withdrawn
  • 1999-10-25 WO PCT/US1999/025046 patent/WO2000026100A1/en not_active Application Discontinuation
  • 1999-10-25 CA CA002316840A patent/CA2316840A1/en not_active Abandoned
  • 1999-10-25 AU AU11336/00A patent/AU1133600A/en not_active Abandoned

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