MXPA00004251A - Oxygen scavenging system and compositions - Google Patents

Abstract

An oxygen scavenging system and composition capable of providing good oxygen absorption activity and capabilities, wherein the system comprises a modified anionic hydrotalcite particulate material and a transition metal ion source.

Description

SYSTEM AND COMPOSITIONS OF OXYGEN SWEEPING Field of the Invention The present invention is related to a novel oxygen scavenging system and the resulting compositions that can be used to retain product quality and improve the shelf life of oxygen sensitive materials. The present compositions can be formed into shaped structures, e.g., films, coatings, three-dimensional solids, fibers, fabrics and the like, as well as in products configured toward or over which the compositions or structure are incorporated, applied to or be part of. a container structure.

BACKGROUND OF THE INVENTION The present oxygen scavenging system comprises a modified anionic, particle-like hydrotalcite in combination with a metal ion. transition or a source for that ion. It can be formed into a composite composition of the system in a carrier that allows the system to be combined with oxygen when it is in the presence of moisture. Specifically, the composition utilizes particles resembling modified anionic hydrotalcite having certain anionic groups and a metal ion d? transition or source for said ion, as is fully described herein below. The oxygen scavenging composition containing particles of the present invention has unexpectedly been found to provide effective oxygen uptake from the interior of a container without adversely affecting the color, taste or odor of packaged products contained therein that ST normally associates with conventional agents and / or secondary oxidation products thereof. The present oxygen scavenging system and the resulting composition have been found to provide high sweeping activity and capacity. The resulting composition has the ability to chemically combine effectively with oxygen, such as from within a container, without undue migration of the components of the oxygen scavenging system or its oxidation by-products from the matrix of the composition. . The inhibition of migration is of particular advantage in that it significantly reduces or eliminates the adverse effects of color, taste or odor of the articles in contact with the composition and also provides a means of using high levels of components. sweeping while filling government regulations directed to quantities of foreign material allowed in food products. . In order to improve conservation, it is a conventional practice to pack food or other materials into laminated packaging material that generally includes a barrier layer, i.e., a layer having a low oxygen permeability. The sheet material may be thin, in which case it is wrapped around the material being packaged, or may be thick enough to form a shaped container body that is provided with a lid or other separate closure. The polymeric sheet material may constitute part or all of the exposed surface area inside the container or its closure means. ST knows how to include an agent d? Oxygen sweep in sheet material. The oxygen scavenging agent reacts with the oxygen that is trapped in the package or that enters the package. This is described, for example, in the Patents of E.U.A. Nos. 4,536,409 and 4,702,966 and in the prior art in these references. The Patent of E.U.A. No. 4,536,409, for example, discloses cylindrical containers formed from said sheet material and provided with metal caps, When the container is formed of a glass or metal body and is provided with a hermetically sealed metal closure, the permeation of oxygen through the body and the closure is theoretically impossible due to the impermeability of the materials that form the body and lid. As a practical matter, metallic cans can reliably impede the entry of oxygen. Nevertheless, some oxygen intake may occur by diffusion between the package or the like placed between a container body and its lid or end portion. It has long been recognized that when conventional containers of these types are used for the storage of oxygen sensitive materials, the storage life of the stored materials is very limited. This quality of the packaged material tends to deteriorate over time, in part because dissolved oxygen is typically present in the package from the time it is filled; and partly due to the oxygen input that occurs during storage. When the container is in the form of > a can, the can end or other closure in many cases includes push components or pull components that are intended to be, respectively, pushed or pulled in order to allow the removal of fluid or other material in the container without removing the closure complete of the container. These pushing or pulling components are often defined by discontinuities or lines of weakness in the closure panel. Problems that may arise in these lines of weakness or discontinuities include the risk of oxygen permeation in the container and the risk corrosion of the metal where the normal protective lacquer coating breaks in lines of weakness or discontinuities. It is desirable to extend the shelf life of packaged products using materials capable of being manufactured into or as part of a film, coating material, closure, packaging or other member of a package intended for storage of oxygen sensitive products. Various types of oxygen scavengers have been proposed for this purpose. For example, it is well known to pack iron powder into a seal for use with dry foods. See literature from Mitsubishi Gas Chemical Company, Inc., "Ageless (R) - A New Age in Food Preservation" (date unknown). However, these materials require the addition of water-soluble salts to improve the oxygen scavenging regime. In the presence of moisture, salts and iron tend to migrate to liquids, producing off-flavors. Similarly, U.S. Patent No. 4,536,409 issued to Farrell et al. recommends potassium sulfite as a sweeper, with similar results. It is known in the art that the ascorbate compounds (ascorbic acid, its alkali metal salts, optical isomers and derivatives thereof) as well as sulfites, bisulfites, phenolics, etc. they can be oxidized by molecular oxygen, and in this way can serve as an oxygen scavenging material. For example, U.S. Patent No. 5,075,362, issued to Hofeldt et al. , describes the use of ascorbate compounds in container closures as oxygen scavengers. U.S. Patent No. 5,284,871 issued to Graff relates to the use of an oxygen scavenging composition made from a solution of a reducing agent and dissolved copper species that are blended into food, cosmetics and pharmaceuticals. Copper ascorbate is used in these examples. The reference indicates that the relatively high level of Cu2 + (- 5 ppm) is required in the feed for the sweeping to be effective but indicates that small amounts of Cu2 + can be combined with oxygen in feed to cause food damage. In order to avoid damage, it is required to reduce the amount of O. of space above or partially flush with the vessel with an inert gas (Col. 5, lines 32-39). A paper by E. Graff, "Copper (II) Ascorbate: A Novel Food Preservation System", Journal of Agricultural Food Chemistry, Vol. 42, pages 1616-1619 (1994) identifies copper gluconate as a preferred raw material. It is also known - well in the scientific literature (See "Polymer Compositions Containing Oxygen Scavenging Compounds", Teumac, FN; and col. WO.91 / 17044, published on November 4, 1991, filed on May Ia, 1991) that the oxidation rate of ascorbate compounds can be significantly increased by the use of catalysts. Typical oxidation catalysts for ascorbic acid and its derivatives are water soluble transition metal salts. In each of the above references, the active component of the agents used of oxygen scavenging systems that are easily transferred to the food or other packaged product or materials or that produce oxidation by-products that are known to adversely affect a wide range of packed material. Hydrotalcite is a mineral that runs naturally, commonly classified as a clay. Generally speaking, clays are broken up into broad groups of cationic materials that are commonly found in natural or anionic materials, which is found rare in nature. These materials are used in a wide range of applications, such as industrial absorbers, catalysts, fillers.; discoloration agents and the like. The hydrotalcite that occurs naturally are hydroxide-carbonate minerals of the formula Mg6Al2 (OH) 16C03.4H20 - " It is well known that the hydrotalcite mineral is strongly bound to carbonate. The carbonate can be expelled by thermal calcination. Recently, hydrotalcites with anions other than carbonate have been synthesized. They are generally double layer hydroxides (LDH) which include anionic hydrotalcite-like compounds (HTLC). They have been described in the Patents of E.U.A. 5,399,329 and 5,507,980 as well as by W. T. Reiche in Chem Tech (1986) 58-63, the teachings of which are hereby incorporated by reference in their entirety. These new materials have anions in their crystal structure that are easily exchanged. It is highly desired to provide an effective oxygen scavenging system and composition having a high oxygen absorption and capacity regime.

It is further desired to provide an oxygen scavenging system and composition which are capable of inhibiting the release of oxidation by-products which may adversely affect the color, taste or odor of the packaged material. It is further desired to provide an oxygen scavenging system and composition which are capable of inhibiting the release of by-products of oxidation which may adversely affect the color, taste or odor of the packaged material. It is further desired to provide an oxygen scavenging composition having the active scavenging system contained within a carrier and the system still provides a high oxygen absorption rate and capacity. It is further desired to provide an effective oxygen scavenging system that is thermally stable and, thus, capable of allowing the packing system to be formed and processed by conventional techniques including processing steps at elevated temperature. It is further desired to provide an effective oxygen scavenging system and composition having the system contained within an appropriate carrier to form at least part of a package or container that improves the storage stability of the oxygen sensitive articles contained therein. .

SUMMARY OF THE INVENTION The present invention is directed to a composition comprising a carrier having uniformly distributed therein an oxygen scavenging system capable of exhibiting high initial oxygen scavenging activity and improved oxygen scavenging capacity while avoiding the improper migration of the components of the composition and their oxidation by product (s) of the carrier. The F inhibition to migration significantly reduces or eliminates the adverse effects of color, taste and odor, of packaged items that are in contact with or contained in a container having the composition. Specifically, the present composition comprises a carrier having a combination of an anionic hydrotalcite-like material and an ion source. of transition metal, as fully described below. F The present invention is further directed to shaped structures containing or derived from the present composition. These structures may comprise one or more layers of an appropriate film to form a closed package (e.g., bag) as well as semi-rigid or rigid containers, including closures, such as sealing sealants, sealing gaskets, sealant compositions applied to the fluid (e.g., corona cap packaging compositions applied by melting), lid covering discs, and the like, formed with or containing the present composition. , Detailed Description The present invention is directed to an oxygen scavenging composition comprising a carrier, which has uniformly distributed therein an effective oxygen scavenging system comprising a modified anionic hydrotalcite-like material and a metal ion source. distributed transition therein, as fully described belowThe present invention further provides an improved container for packaging materials, such as foods, beverages and the like, which are susceptible to oxidative degradation. The present improved container is capable of retaining improved product quality and shelf life of the packaged material without adversely affecting the color, taste or odor of the packaged material by the present oxygen scavenging composition. It further provides a packaging system having high levels of oxygen scavenging agent therein while filling government regulation standards with quantities of such agents contained in food products. The term "system", as used herein and in the appended claims, refers to active oxygen scavengers comprising at least one modified anionic hydrotalcite-like material in combination with at least one metal ion source. of Transition. The transition metal ion source can be present as a transition metal compound that forms a substantial mixture. homogeneous with material similar to modified anionic hydrotalcite; or as a transition metal compound coated on the surface of the particulate material similar to modified anionic hydrotalcite; or as transition metal ions substituted for at least a portion of the non-transition metal ions, M "and even M, of the modified anionic hydrotalcite particulate material, or a combination thereof. is used herein and in the appended claims, refers to the active oxygen scavengers forming the system and a carrier component, the carrier can be a polymer matrix in which the particulate material forming the present system d) oxygen scavenging is uniformly distributed, or a film or mat (woven or non-woven) which removes the particulate material substantially evenly distributed therein or deposited therein, or a bag or sack permeable to it. the moisture contained in the present particulate material distributed therein The material similar to anhydrous hydrotalcite which is a component of the oxygen scavenging system of the This invention has the general formula: W \ -W ", (OH); nH, 0 (x + y) - wherein M "represents magnesium (preferred), calcium, zinc, nickel, copper or cobalt or mixtures thereof in their valence state plus 2, M represents aluminum (preferred), chromium, or iron or mixtures thereof in its valence state plus 3. In certain cases the present HTLC may also contain Ml cations representing an alkali metal cation selected from sodium (preferred), potassium or mixtures thereof having a valence state plus 1. M1 may be present, when "a" (as defined below) has a value of at least 2, in a molar quantity and equal to a value from 0 to approximately 0.5 The mdlar ratio of Mp to M111 is from 1 to 5; represents hydroxyl groups, x has a numerical value of about 0.1 to 0.5, and n has a numerical value from 0 to 4 and generally from 1 to 4. symbol A of the above formula represents, at least in part, a group of anion-containing oxygen scavenging This oxygen scavenging group or containing anion can be, for example, inorganic anions such as bisulfite, dithionite and the like which are capable of reacting with oxygen or organic anions such as for example, ascorbates, thiolates or phenolates and the like which are capable of reacting with oxygen. The remainder of the anion A being residual anion of the HTLC precursor, as fully described below. the anion A should be at least about 60 mole%, preferably about or less about 80 mole% and more preferably at least about 90 mole% in the form of the inorganic or organic oxygen scavenging anions described above with the remaining residual anions of the original hydrotalcite and / or other anions. The symbol "a" of the above formula represents the numerical value of the valence of the anion A. For example, the value of "a" for a anion of dithionite is 2, while the value of "a" for the bisulfite, ascorbate or phenolate. 1. The value of "a" for the residual anion will depend on the identity of the anion and, in general, will have a value of 1 to 3. F in general, when the present material similar to modified anionic hydrotalcite has anions To which mainly represents monovalent anions, such as bisulfite, phenolate or ascorbate, as ST described above, or ST form in a manner that does not provide M1 as part of the resulting product, the oxygen scavenger of the present invention can be represented by the General Formula : W ^ W (OH); nH, 0 where each symbol is the same as the one defined above. The term "ascorbate anion" as used herein and in the appended claims refers to the deprotonated spice of ascorbic acid, in either its D or L form and any derivative, or analog thereof, including, for example, Erythorbic acid and mixtures thereof. It is preferred that the ascorbate anion be selected from the deprotonated species of ascorbic acid D- or L-, or fatty acid derivatives of ascorbic acid as well as mixtures thereof.

The term "phenolate anion" as used herein and in the appended claims refers to (i) deprotonated hydroxyl group containing aromatic ring compound or condensed aromatic ring. Examples of phenolic compounds from d? which the phenolate anion can be derived include phenol, pricatecol, resorcinol, pyrogallol, pyrocatechol monoethyl ether, resorcinol monoethyl ether, hydroquinone, 1,4-trihydroxybenzene, tetrahydroquinone, 2,4-dibutyl phenol and the like; or (ii) hydroxyl group containing aromatic ring or fused aromatic ring compounds further containing a carboxylic acid desprotonate group such as salicylate anion, 3-hydroxy benzoate, 4-hydroxybenzoate, 3, 4, 5-trihydroxybenzoate and the similar. The term "hydrotalcite-like" is a recognized term in the art (see Cavani et al Catalyst Today 11. 173, 1991) and is used herein in a manner consistent with such use. The present modified anionic hydrotalcite-like materials can be formed by a variety of means. In a case, an anionic HTLC having a labile anion can be used as the precursor in forming the present material. The anion of the precursor anionic hydrotalcite-like material must be F sufficiently labile to readily exchange with the oxygen scavenging anion. HTLC having lower alkanoic acid anions, such as a C-C5 monocarboxylic acid anion (e.g., formic, acetic, propionic or butyric acid anions or the like) is a preferred anionic HTLC to be used as the precursor material. The formation of said precursor material is described in the U.S. Patent. 5,399,329, the complete teachings of which are incorporated herein by reference. The present oxygen scavenging anionic hydrotalcite-like component of the present system is formed by anion exchange of the above-described precursor material, in the absence of oxygen, with alkali metal or alkali metal salts of an oxygen scavenging anion, described in the foregoing. Alternatively, the present modified anionic hydrotalcite-like material can F be formed by reacting, in the absence of oxygen, either the salt or conjugated acid (protonated form) of at least one of the present oxygen scavenging anions with HTLC having anions of carbonate. The reaction can be carried out in deoxygenated water as the reaction medium. The reaction product is washed with deoxygenated water in the absence of atmospheric oxygen to produce an active water-insoluble oxygen scavenging material of the present invention. Yet another way of forming the modified anionic hydrotalcite-like material present uses previously calcined hydrotalcite. The calcined hydrotalcite without associated anions can be reacted with conjugated acids of the oxygen scavenging anions described above in the absence of oxygen to provide the present materials. In the case of bisulfite, this can be achieved by using a solution of sulfur dioxide in water. In yet another method, an appropriate source of trivalent metal (such as aluminum hydroxide) can be reacted, in the absence of oxygen, with an appropriate source of divalent metal (such as magnesium oxide or nickel hydroxide) in the presence of conjugated acids of the oxygen scavenging anions described above to provide the materials present. The preferred modified anionic hydrotalcite-like material used to form the oxygen scavenging system of the present invention has magnesium as M11. However, the magnesium can be replaced at least partially with a transition metal ion, such as cations selected from nickel, cobalt, zinc, copper, manganese or mixtures thereof. In addition, the preferred material has aluminum as Mp? . However, aluminum can be partially replaced (up to about 50 mole percent) of the family of cations selected from chromium, iron or mixtures thereof. It is believed, although it does not mean that it is a limitation to the present invention, that the HTLC precursor has the ability to have the oxygen scavenging anions described above becoming part of the structure of the HTLC. Because the oxygen scavenging HTLC present has a plate-like structure with a small thickness of about 0. 005 to 0.1 microns (typically 0.02 to 0.06 microns) and a ratio between width to thickness dimensions of at least about 50 and generally in the range of 50 to 5000 and typically 50 to 1000, the greatest ion exchange occurs in the surface of the plate. This allows the oxygen scavenging anion to be able to react easily with oxygen in the presence of moisture to provide the desired oxygen scavenging agent. In addition, it is believed that the currently modified HTLC reacts with any oxidation by-products (through the hydroxyl group) or the oxidation by-products that can be formed are adsorbed to or absorbed within the crystal nature of the present modified HTLC. The present oxygen scavenging agent is formed by anion exchange to provide an oxygen scavenging anion containing HTLC as described above. The anion A of the present agent should be at least about 60 mole percent oxygen scavenger anion, with preferably at least about 80 mole percent and more preferably at least about 90 mole percent. Minor molar percentages may be acceptable where the lower amount still provides sufficient oxygen scavenging activity for a particular application. The exact percentage can easily be determined by one skilled in the art, however, the high degree of anionic sites located on the surface of the HTLC provides the ability to provide a high capacity oxygen scavenger. This capability allows one to achieve prolonged storage capacity of the resulting packaged product. The amount of oxygen scavenging agent will depend on the expected application of the resulting sweeping composition. When large amounts of composition are used to sweep small volumes of oxygen (such as in pot coating applications), the amount of oxygen scavenging agent may be as low as about 0.5 weight percent of the composition and preferably at least 1 percent by weight d? the composition. In other conventional applications, such as cap liners and the like, where the charge of the particle in the polymer carrier is low and / or the amount r of composition is small, the amount of oxygen scavenging agent should be when less about 2 weight percent, preferably 2 to 20 weight percent, more preferably 4 to 15 weight percent based on the weight of the composition The exact amount of oxygen scavenging agent required A particular application can be easily determined by the artisan The present invention provides a means to achieve a broad scale of sweetener agent content that includes high weight percentages The oxygen scavenging system of the present invention has been found to provide a degree high activity, regimen and oxygen scavenging capacity when the agent is placed in the presence of oxygen and moisture.D This way, the HTLC system acts The above description must be maintained in the absence of oxygen during formation and the absence of oxygen from moisture during storage. When the present system is formulated towards a composition d? Oxygen sweep with a carrier, such as a polymorphic matrix, the carrier must be able to d? maintain the system substantially? free of moisture to the degree necessary to trigger (initiate) the occurrence of a high oxygen scavenging regime to provide conservation of the packaged goods contemplated, even though the HTLC has the capacity d? Sweeping oxygen when used alone, it has unexpectedly been found that the present system comprising modified HTLC and a source of transition metal ion provides a composition having improved oxygen scavenging activity and capacity. In this way, the present system and composition are able to remove initially? oxygen inside the atmosphere d? a container at a high initial rate and has the ability to remove larger quantities of oxygen per unit of the system d? which can be obtained by compositions that only contain a modified HTLC. In addition, this activity and unexpected improved sweep capability is provided by the present system without allowing the components of the present system and / or any resulting byproducts of oxidation to migrate towards y. adversely affect the color, taste, or smell of the articles contained within the resulting container, the modified HTLC oxygen scavenging component of the present system is used in combination with small amounts of ions d? transition metal. These ions may be provided for the presence of an inorganic or organic transition metal compound and / or by ion replacement with some M "and / or M111 of the F HTLC. this mixture or combination has been found to provide a composition having activity, and improved oxygen scavenging capacity. It has been unexpectedly found that a highly effective oxygen scavenger can be obtained by combining the above-described modified HTLC with a transition metal compound. . The transition metal compound can be in the form of a salt, chelate, complete or compound in which the transition metal is associated with other elements or groups by ionic or covalent bonds. F Metal? S d? Transition found useful in the present are those of the seri? d? metals of the Periodic Table in which the filling of the shell more external to eight electrons is interrupted to take the penultimate shell from 8 to 12 or 32 electrons. These elements use both their penultimate shell orbits as well as the outermost orbits of the shell in the link.

In this way, the transition elements include elements of the first transition series of; the Periodic Table composed of the elements 21 to 29 (Se, Ti, V, Cr, Mn, Fe, Co, Ni and Cu or mixtures thereof) and, of these, the preferred metals are cobalt, copper, tin iron, nickel and manganese, or mixtures d? the same with copper and cobalt being more preferred. The positive oxidation state of the metal when introduced as part of the system is not necessarily that of the active state that results in improved activity and capacity to the system. Appropriate transition metal compounds to provide the presence of the metal ion may be in the form of an organic transition metal complex, chelant or organic carboxylic acid salt. Examples of suitable organic transition metal compounds are: (1) Metal salts of mono-, di- and polycarboxylic acids having a carbon chain length of or about. The carbon chain may be aliphatic or aromatic, substituted or unsubstituted, may contain unsaturation or may be a fatty acid. The illustrative examples d? said metal salts are: aliphatic monocarboxylic acids such as formic, acetic, propionic, butyric,. valico, caproic, caprylic, cáplic, • lauric, tridecanic, myristic, pentadecanoic and the like; F aliphatic dicarboxylic acids such as oxalic, malonic, succinic, glutaric, adipic, pyrolic, azelaic, sebacic and the like; polycarboxylic acids such as citric acid and the like; acids containing unsaturation such as oleic, linoleic, sorbic, glutaconic, hydromuconic, octenedioic acids and the like; F aromatic acids such as benzoic, salicylic and the like and may be unsubstituted or substituted; fatty acids such as, higher carbon monoacids, preferably having the carboxyl group terminally located, for example, palmitic, stearic, nonadecanoic acid and the like; the acid may be substituted with hydrocarbyl groups F which may be composed of straight or branched chains, typically an aliphatic group having 1-6 carbon atoms or an aromatic group, for example. cyclohexanbutyric acid and 2-ethylhexanoic acid. In addition, the acids may have other substitution groups such as aldehyde or hydroxyl groups, for example, as they are contained in glycoxylic acid, glycolic acid, or gluconic acid and the like; (2) Metal / base chelate acid complexes such as those formed with ethylenediaminetetraacetic acid, phthalocyanine, tetraphenyl porphines and naphthalocyanines, and the like; (3) Metal sulphonic acid containing compounds such as p-toluenesulfonic acid and the like; (4) Salt of Metal Ionomer in which a polymeric counterion is employed. These ionomers are well known in the art; or (5) Metal ligands in which the transition metal is associated with acetylacetonate, benzoylacetonatb, 2, 2, 6,6-tetramyl-3,5-heptanedione and the like. Preferred organic transition metal compounds are, for example, cobalt (II) neodecanoate, cobalt (II) oleate, cobalt (II) 2-ethylhexanota, copper (II) stearate, copper (II) 2-ethylhexanoate, copper ( II) palmitate, copper (II) acetate, copper (II) gluconate, cobalt (II) acetate, iron (II) acetate, iron (III) acetylacetonate, iron (II) gluconate, manganese (II) acetate, nickel (II) 2-ethylhexanoate and the like. . Alternatively, compound d? metal d? transition can be in the form of a salt d? Inorganic transition metal. The salt can? be a salt soluble in water or insoluble in water. The salts may be transition metal halides, sulfites, sulphates, sulphides, phosphites, phosphates, pyrophosphates, phosphides, hypophosphites, nitrites, nitrates, oxides, carbonates, hydroxides, chlorates, bromates, chromates, chromites, titanates, borides, perchlorates. , tetrafluoroborates, tungstates and the like and mixtures thereof. Examples of such salts include Cobr? (I or II), bromide d? Copper (I or II), Copper chloride (I or II), Copper oxide (I or II), Copper carbonate (II), Copper fluoride (II), Copper (II) hydroxide, Copper iodide ( I or II), Copper (II) nitrate, Copper (II) nitrite, Copper (II) sulfate, Cobalt (II) bromide, Cobalt (II) carbonate, Cobalt (II) chloride, Cobalt (II), Cobalt (II) nitrate, Cobalt (II) sulfate, Cobalt oxide (II or III), Iron bromide (II or III), Iron chloride (II or III), Iron fluoride ( II or III), iron nitrate (III), iron oxide (II or III), iron perchlorate (II or III), iron phosphate (III), iron sulphate (II or III), iron sulphide ( II), Manganese (II) bromide, Manganese carbonate (II), chloride Manganese (II), Manganese oxide (II, III or I FV), Manganese hypophosphite (II), Manganese nitrate (II), Manganese sulfate (II), Nickel (II) bromide, Nickel chloride (II) ), Nickel (II) hydroxide, "Nickel (II) oxide." The preferred inorganic salts useful for forming the present oxygen scavenging system and composition are copper (II) sulfate, copper (I) chloride, copper (II), cobalt (II) sulfate, iron (II) chloride, iron (III) chloride, iron (II) sulfate, manganese (II) sulfate, tin sulphate (II) and nickel sulfate (II) The term "compound" as used herein and in the appended claims refers, except where specifically indicated otherwise, to materials having the transition metal in a non-zero valence state and bound to an opposite fraction, such as in a salt, complex, chelate or other form that provides a stable material. oxygen scavenger of the present invention comprises modified HTLC oxygen scavenger and a source of transition metal ion. When the source of transition metal ion is in the form of a compound d? Inorganic or organic transition metal, as described above, can be physically mixed with the particle modified HTLC to provide a substantially uniform mixture of the modified HTLC and transition metal compound. this mixture is uniformly distributed in the carrier to provide the "oxygen scavenging composition in the present invention." The physical mixture can be formed by initially mixing the modified HTLC and a transition metal compound and then introducing this mixture into a carrier. the modified HTLC and the transition metal compound can be mixed separately with the carrier and then each of the charged carriers can be mixed together to provide a uniform mixture of the transition metal compound and the modified HTLC in a carrier matrix. Modified HTLC can be coated with the transition metal compound to provide an intimate mixture of the two components forming the oxygen scavenging system of the present invention As stated above, the modified HTLC has a layer structure and, of this way, it provides a high surface area that can and at least partially coated with a transition metal compound. This coating can be made by any conventional manner such as by treating HTLC modified with a solution of transition metal compound to the point of incipient moisture and then removing the solvent. The present modified HTLC system / transition metal compound can be in intimate mixture of modified HTLC and transition metal compound in combination with modified HTLC coated with transition metal compound. Still further, the transition metal compound can be used as a source of transition metal ion which is an ion exchanged with a portion of the non-transition metals (e.g., Ca + 2, Mg + 2) of the modified HTLC. This can be achieved by introducing a transition metal compound (preferably as a salt) to the reagents used to form modified HTLC. Alternatively, a preformed modified HTLC may be contacted with a solution of a transition metal salt over a period of time and at elevated temperature to cause ion exchange to occur (eg, at least 60 minutes). preferably from 120 to 360 minutes of contact time It is desirable to wash the resulting modified HTLC with water or a mixture of water and alcohol to remove the exchanged salt byproduct.The resulting product may be composed of modified HTLC having metal compound of transition intimately mixed with it and / or coated on its surface as well as transition metal ion as part of the modified HTLC. The aqueous solution used to coat the transition metal compound towards and / or ion exchange of the ion d? Transition metal with the modified HTLC must be free of oxygen. The process must be done in an oxygen-free atmosphere. The oxygen scavenging combination of the present invention has been found to provide activity and scavenging rate of effective oxygen when the agent is placed in the presence of oxygen and moisture. In this way, the currently described oxygen scavenging compositions of the invention should be maintained in the absence of oxygen during formation and the absence of oxygen or moisture during storage. When the present system t is formulated into an oxygen scavenging composition with a carrier, such as a polymorphic matrix, the carrier must be able to keep the agent substantially free of moisture to the degree required to trigger (initiate) a high rate of Oxygen sweep The amount of sweep component d? HTLC oxygen modified from the system will depend on the expected application of the resulting scavenging composition. When large amounts of composition are used to sweep small volumes of oxygen (as might be the case if relatively thick polymorphic coating is used to coat the entire inner surface of a can), the amount of modified HTLC oxygen scavenging component can be as low as about 0.05 weight percent of the composition and preferably at least 1 weight percent of the composition. Generally speaking, modified HTLC can be used on the t scale of 0.05-90% based on the total weight of the composition; more preferably 0.5-40%, and especially preferably 1.0-25% based on the total weight of the composition. In some conventional applications, such as cap coatings, crown packing compositions, can sealers, and the like, wherein the charge of the particles in the polymer carrier is low and / or the amount of composition is small, the amount of component d? The modified hydrotalcite oxygen scavenging may be at least about 1 weight percent, preferably 2 to 40 weight percent, and more preferably 3 to 25 weight percent based on the weight of the composition. The amount of modified HTLC oxygen scavenging component required for a particular application can be easily determined by the artisan. When the particulate material sweep d? Oxygen is incorporated into a package, the amount is usually F at least 0.05 weight percent (e.g., 0.05 to 90%) based on the total weight of the composition, generally at least 1% and preferably at least 2 % (e.g., 2 to 9%, preferably 2 to 40% and more preferably 2 to 25%). In the case of a plastisol, lacquer, or hot melt applied to the central panel of a closure, where the carrier does not otherwise serve as a package, the amount may be much higher. For example, the charges d? 20 to 60 percent by weight, or in some cases up to F 90 percent? N weight can be worked. When the composition is in the form of a film, mat, bag or sack, the oxygen scavenger must be present in an amount to effectively sweep oxygen during the contemplated storage period of the container for the appropriate contents. An amount of approximately 0.01 to 2 grams of the sweeping combination will effectively sweep oxygen from a normal sized container. The present invention provides the ability F to achieve a wide range d? content of modified HTLC scavenger agent including high weight percentages. The transition metal component described above should be present in the present composition F in a molar ratio of modified HTLC to transition metal of the transition metal compound from about 3000: 1 to 1: 1 with 2000: 1 to 5. : 1 being preferred and from 100: 1 to 10: 1 being more preferred. In certain applications, the ratio may be higher or lower to provide effective oxygen scavenging. The exemplary modified HTLC and transition metal compound suitable for use in the present invention are finely divided solids which are particularly suitable for replacing part or all of the filler commonly encountered in sealant, coating, or film compositions which are intended applications. at the moment. The particle size of these components can vary from 10 to F500 microns with 20 to 50 microns being preferred. The present composition as an integer is effectively anhydrous, that is, it provides a content d? lower humidity qu? It is necessary to trigger (initiate a substantial regime) the oxygen scavenging. DT this way, it is preferred that the carrier component of the composition is a polymorphic matrix which is also preferably anhydrous. Generally, the polymorphic matrix substantially protects the moisture scavenger under normal atmospheric conditions, and therefore, the oxygen scavenging agent remains substantially inert to the sweeping activity. However, once a high degree of moisture is reached, as in a closed package environment of food products, the sweep activity is initiated or triggered. The ingress of moisture into the polymer matrix carrying the composition is conventionally accelerated by common practices such as hot filling, sterilization, pasteurization, retort and the like. The polymorphic matrix must be sufficiently permeable to allow moisture and oxygen to pass into the mass of the matrix and make contact with the particulate materialIn one embodiment of the present invention, the carrier of the present composition comprises a material d? polymorphic matrix, TS say, polymeric material (including optional additives such as plasticizers, fillers, surfactants, etc.) which will form a solid matrix having distributed thereon the oxygen scavenging system of the present invention. The polymorphic matrix carrier should be selected with respect to the nature of the composition (film, dispersion, latex, plastisol, dry mixes, solution or melt) and its use as part of the container and / or closure in a conventional manner. r Can the carrier? selected from at least one polymeric material that can form, a solid or a semi solid matrix. The polymorphic carrier can be derived from a variety of polymers that are available from a variety of bulk physical configurations such as films, dispersion, latex, plastisol, dry mix, solution or melt (e.g., thermoplastic meltable polymer). The particular physical configuration of the selected polymer will depend, d? the final structure towards which the present composition is eventually formed or incorporated. The polymorphic matrix is derived from polymer types that can be thermoplastic or thermosettable. The primary functions served by the polymeric matrix for purposes of the present invention are to provide a compatible carrier (a material that is stable under normal packing temperature conditions and does not deactivate the oxygen scavenger activity of the present metal ion system). modified hydrotalcite transition) for the oxygen scavenging system that ST completely describes above and allow the entry of both oxygen and water into the composition under dictated conditions and d? a way that allows them to get in touch with the components of the system. The range of the polymer in general can be very broad. however, the polymer matrix can also be selected to perform additional functions depending on the physical configuration in which it is provided in a final structure to which it is configured or incorporated. In this way, the particular polymer or mixture of polymers selected finally will be determined by the end use in which it exerts its oxygen scavenging effect. Consequently, appropriate polymers from which the polymorphic matrix can be derived include polyolefins, vinyl polymers, polyethers, polyesters, polyamides, phenol-formaldehyde condensation polymers, polysiloxanes, ionic polymers, polyurethanes, acrylics and naturally occurring polymers. such as cellulosics, tannins, polysaccharides and starches. Suitable materials for use as the polymer matrix component of latex compositions, e.g., for can ends, are described in U.S. Pat. 4,360,120; of E.U.A. 4,368,828 and EP 0182674. Suitable polymeric materials for use when the compositions are organic solutions or aqueous dispersions are described in U.S. Pat. 4,360,120; E.U.A. 4,368,828; and GB 2, 084,601. Suitable materials for use in thermoplastic compositions include the materials proposed in US Patents. 4,619,848; E.U.A. 4,529,740; E.U.A. 5,014,447; E.U.A. 4,698,469; GB 1,112,023; GB 1,112,024; GB 1,112,025 and EP 129309. The teachings of each of the references cited above are F herein incorporated by reference in their entirety. In particular, the polymeric carrier can generally be selected from polyolefins, such as, for example, polyethylene, polypropylene, ethylene / propylene copolymers, ethylene / propylene modified with acid copolymers, polybutadiene, butyl rubber, styrene / bitadiene rubber, styrene carboxylated / butadiene, polyisoprene, styrene / isoprene / styrene block copolymers, styrene / butadiene / styrene block copolymers, styrene / ethylene / butylene / styrene block copolymers, ethylene / vinyl acetate copolymer, ethylene / acrylate and ethylene / (meth) acrylate copolymers (eg, ethylene / butylacrylate or ethylene / butyl methacrylate copolymers), ethylene / vinyl alcohol copolymers, alternating copolymers of ethylene or propylene / carbon monoxide, homopolymers and chloride copolymers of vinyl, polymers and copolymers of dichloride d? vinylidene, F ethylene / acrylic polymers, polyamides, and vinyl acetate polymers, and mixtures of one or more of these. The polyethylenes found useful in forming the present composition include high density polyethylene (HDPE), polyethylene d? low density (LDPE), linear low density polyethylene (LLDPE), ultra low density polyethylene (ULDPE) and the like as well as copolymers formed from? tylene with one or more different lower alkenes (eg octane) ) and the like. Compositions in accordance with the invention particularly useful for forming films and the like may comprise a thermoplastic polymer such as, for example, polyethylene or polyethylene copolymers such as ethylene / vinyl acetate and the like or polyethylene mixtures such as, mixtures of HDPE and butyl rubber; polyethylene and copolymer of ethylene / acetate d? vinyl, as well as polyethylene and styrene / butadiene / styrene block polymer and the like. Polyethylene, if used, TS < preferably a low density polyethylene, and it can be a polyethylene d? Very low or ultra low density that can be branched or linear. The ethylene / vinyl acetate copolymer, if used, preferably has a melt index in the range of 3 to 15, preferably 5 to 10, and generally contains 5 to 40%, preferably 5 to 30%. ? vinyl acetate.

Particularly preferred compositions for use as coatings and the like for semi-rigid packages (e.g., bot? S) are a plastisol or a dry polymer blend. These can be used in combination with a plasticizer to form the polymer matrix. Suitable materials to be used when the compositions are plastisols include homopolymers and copolymers of vinyl chloride. Instead of preparing such compositions as true plastisols, they can be provided as dry mixtures of the polymer and plasticizer. The proportion of plasticizer present in a plastisol d? Vinyl resin can be any conventional proportion, typically from 30 to 150 parts by weight of plasticizer per hundred parts of vinyl resin. The polymer carrier can be formed from various thermosetting resins such as polyurethanes, phenolics, resins d? epoxy-oster, epoxy resins, polyesters and alkyds. These resins are normally formed in solutions or suspensions with organic liquids and are applied to the intimate surface of a vessel followed by high temperature application to remove the liquid and cause solidification (eg, by cross-linking) of the r? v? stimulus of resin on the substrate.

The carrier d? matrix d? The polymer of the present composition can be selected from those used to form coatings on at least a portion of the inner surface of a package (e.g., a rigid container such as a can, can lid, box, carton, or the like). The polymer matrix can be selected from classes of polymer commonly referred to as epoxies, phenolics (e.g., phenol-formaldehyde condensation polymer), lakes (e.g., cellulose esters or ethers, shellac, resins). of alkyl and the like), polyurethanes and the like. The carrier matrix can be mixed with the components of the above-described oxygen scavenging system to provide encapsulated particles that can be subsequently used in a second polymer matrix or applied to (such as by application of solvent or melt) the surface of a second material carrier. The polymeric carriers used to form the composition may also contain conventional plasticizers, including phthalates, adipates, glycols, citrates and epoxidized oils and the like, such as, for example, dioctyl phthalate, diisooctyl phthalate, or diisodecyl phthalate, which " are readily available Other plasticizers usable with butyl benzyl phthalate, acetyl tributyl citrate, diethyl diphenyl phosphate and diisobutyl phthalate A particularly useful combination of plasticizers for use with a vinyl chloride / vinyl acetate copolymer resin is a mixture of diisodecyl phthalate and diisooctyl phthalate in a weight ratio of about 7-8: 1, In addition, the carriers of the invention may additionally contain inert filler, slip aids, process aids, pigments, stabilizers , antioxidants, tackifying resins, foaming agents and other conventional additives in quantity s conventional, depending on the nature of the composition and its final use. If the carrier comprises a thermoplastic polymer, the total amount of these additives is generally less than 10%, more preferably less than 3%, based on the total weight of the composition. However, when the carrier is in the form of a plastisol, dispersion, organic solution or latex, the amounts of additives based on the total weight of the composition may be higher. When an antioxidant is incorporated, it must be present in amounts capable of stabilizing the polymorphic composition against degradation due to free radicals formed during processing. However, the amount of antioxidant should be. small enough to allow the present sweeping system d? modified HTLC oxygen / transition metal compound of the present composition react effectively with molecular oxygen. The specific amount will depend on the antioxidant? used and can be determined through minor experimentation. In certain cases, the amount d? Normally used filler may be at least partially replaced by the particle-modified HTLC oxygen scavenging agent. solids currently required that have been mixed, coated or exchanged in ions with the transition metal compound, as described above. A preferred aspect of the invention is that the oxygen scavenging system should remain substantially inert in the composition and in the package or other solid deposit formed with the present composition until the composition is on or in the se container. Exposure of the composition to the high humidity that normally exists within a se container, therefore, will result in sufficient moisture permeation into the composition and will cause the present oxygen scavenging system to initiate oxygen scavenging to a high degree . This will result in improved shelf life of the packaged material. In addition, the sweeping reaction can be further accelerated by heating the composition sufficiently while it is in the closed container to cause increased moisture permeation. In this way, the oxygen scavenging system will preferably remain substantially inert in the carrier until the scavenging reaction is accelerated by heating in the presence of moisture. The scavenging reaction of the present composition can be accelerated by pasteurization (typically at 50a-100C) or sterilization (typically at 100a-150aC) of the container after it is filled with an aqueous filler and se. This shot seems to be a consequence of the present composition, when heated, which allows moisture to penetrate into the composition and make contact with the present oxygen scavenger system. The moisture is trapped in the composition, thus leading the sweeping system into contact with sufficient water to allow reaction with the oxygen present. This oxygen can be permeated through the composition either of the oxygen trapped inside the container when it is filled or subsequently enters the container of the surrounding atmosphere.

Although some conventional oxygen scavengers degrade when subjected to elevated temperatures, the present oxygen scavenger system has been found to be stable at the elevated temperatures commonly experienced in processing polymers into films or coatings, removing solvents from compositions Plastisol, pasteurization, sterilization and similar processes commonly found in packaging technology. The composition of the invention can be formulated in any convenient form, such as melt extrusion, plastisol, organic solution, dry mix, latex or dispersion. The main ingredients of the composition, in addition to the sweeping system d? Oxygen and carrier are typically typical of those conventionally present for the intended purpose. It is preferred that the composition is not aqueous (ie, an anhydrous solution, plastisol or thermoplastic melt) so as to prevent the start of the scavenger reaction within the composition. The present composition can be used to form a film carrying the present oxygen scavenging system. The carrier can be formed of a polymeric material, such as those described above, capable of forming a film and on the surface thereof is deposited the present scanning composition d? oxygen. The film may be composed of a single layer or a plurality of layers. The surface of the film may be coated with the present oxygen scavenging composition by forming a suspension or dispersion of the particles in a polymer and depositing the suspension or dispersion by a conventional means, such as spraying or knife coating application or similar, directly to the surface d? the carrier film. The particulate nature of the carrier film will depend on the contemplated application and the ability of the carrier formed to have the oxygen scavenger adhered to its surface and substantially retain its integrity during use. Alternatively, the carrier can be T? the shape of a fibrous mat (woven or non-woven). The present oxygen scavenging composition is contained in the interstices of the mat structure. The fibers forming the mat can be formed of any suitable material or synthetic fiber such as cotton, glass, nylon, polyethylene, and copolymers of ethylene with one or more ethylenically unsaturated monomer, polypropylene and copolymers of propylene with one or more ethylenically unsaturated monomer and the similar. The particulate nature of the carrier mat will depend on the application of its use and the ability of the mat to retain the components of the oxygen scavenging system within the interstices of the mat structure during use. The scavenger may be deposited towards the mat structure by any means such as by immersing the mat towards a dispersion or suspension of the scavenging system and then separating the liquid from the mat or by first forming scavenger particles / polymer composition which is deposited by fusion on and towards the mat structure. In another embodiment, the present oxygen scavenging system may be retained within a carrier in the form of a bag or bag of appropriate size to be inserted into a container having an oxygen sensitive material therein. The bag or sack should be enough? porous to allow moisture and F oxygen to penetrate through the material that forms the bag or bag to conditions d? room temperature. The present composition d? Oxygen scavenging in this way is composed of the bag or bag carrier having in it the oxygen scavenging system, itself, or contained in a polymer matrix and provided in the form d? small particles of sufficient particle size to allow the bag structure to retain the particles in it. The bag or ejaco can be formed of natural or synthetic materialssuch as paper, cotton cloth, polymer films and the like in well-known ways in "packaging" technology A fourth embodiment is to use a carrier in the form of a porous inorganic material, such as a ceramic having the present Oxygen scavenging system distributed therein Ceramic can be formed to any desired configuration (e.g., spheres, cubes, cylinders and the like) and whose size TS is suitable for insertion into the container having the oxygen sensitive material Useful porous inorganic materials include conventional clay, cement pastes and the like It has been found that the above-described oxygen scavenging compositions can be used for the preservation of oxygen sensitive foods stored at ambient conditions. advantage over those compositions that have oxygen scavengers directly mixed towards and e form a filler of a polymer matrix because the present compositions inhibit the release of scavenging agent and / or oxidation by-products that can contaminate the food material. The oxygen scavenging system of the present invention is composed d? particulate material that contains, as a part of its structure, a fraction of sweep, of oxygen triggered by humidity. It has been found that the nature of the system is such that the oxygen scavenging fraction is highly reactive with molecular oxygen, however, it is bound to the hydrotalcite in a manner that substantially impedes the migration d? the fraction of oxygen scavenging or its oxidized product towards the packed material. Therefore, the present invention unexpectedly provides a composition d? Highly desired oxygen sweeping that does not cause discoloration or subtraction of the flavor of the packaged food product, >; The amount of the present oxygen scavenger containing particles depends on the type of application. When the ST particulate material enters a package, the amount is usually at least 0.5 weight percent based on the polymeric matrix material, generally at least 1% and preferably at least 2%. It is generally unnecessary for the amount to be greater than 20% and 4% -10% TS frequently a convenient maximum. 'In the case of a plastisol, lacquer or hot melt applied to the central panel of a closure, where the matrix otherwise does not serve as a packing, the particle charges d? Sweeper can be higher. For example, loads of 20 percent by weight to 60%, or in some cases up to 90%, can be worked. When the composition is in the form of a film, mat, bag or sack, the oxygen scavenger must be present in an amount to effectively sweep oxygen during the contemplated storage period of the container for the appropriate contents. An amount on the 0.01 to 2 gram scale of the oxygen scavenger having at least about 60 mole percent oxygen scavenging anion A is usually sufficient to provide the desired oxygen scavenging capacity in a container d? normal size (50-1000 ml). The present composition can be used as part of a packaging container that can provide storage stability to the material packaged therein without detracting from the taste, odor of the material. The present composition must be exposed to the internal atmosphere of the resulting sealed container in any form such as a coating on all or a portion of the inner surface of the container body or closure element (e.g., lid, can end) or as an insert in the form d? a film, mat, ball, sack or ceramic structure. The composition d? the invention in the form of a film, for example, can be laminated to cardboard to form cardboard boxes of pinion top. The film can comprise layers d? Oxygen barrier and / or thermally sealable layers. The invention formed with a polymer carrier in the form of a film can be applied as a central panel covering on a container closure. The closure can be a lid, end d? boat, cap or film material. The invention also includes container closures which carry a solid deposit formed on the closure from a polymer matrix or film composition and which is positioned to seal around, or on a line of weakness, in the closure. The solid deposit may be a package deposited around the closure and formed of the composition. Instead of, or in addition to the reservoir which is said package, the composition can be deposited on the inner face of a closure in a position where there is a discontinuity or line of weakness around a pushing or pulling component to open the sealed container by the closing. The container occupies, as is conventional, only a minor part of the exposed surface area of the closed container, often less than 25% of the surface area. In this way, the area of the solid deposit can be very small r relative to the area of the container. Despite this, the invention can provide greatly improved storage stability to the contents. The invention also includes filled containers, sealed with said closures. The sealed container comprises a container body, the closure fitted therein, and the packaged material that is contained within the container body. The container body is preferably made of glass or metal. The F closure preferably is made of metal. The packaged material may be any beverage, food material or other material that is to be stored within the container, but the invention is of particular value when the filling is a material whose shelf life or product quality is normally restricted due to the input of oxygen or contamination during storage. The container body may be a canister, generally made of metal, in which case the closure is a can end. F Generally the complete closure is made of metal or polymeric material, but the closure panel may include a removable component of either metal or polymeric material.

Instead of a can body, the container body can be a bottle or jar in which case the closure is a lid. The bottle or jar is preferably made of glass but can be made of a polymeric material with very low oxygen permeability. The lid can be made of a polymeric material, for example a polypropylene, which can include a barrier layer. metal and may include a push or pull component of metal or polymeric material, The cap may be a crown cap such as a lever cap crown or twist spacer, a screw cap, tab cap, pressure / torsion, or pressure / torsion cap, screw cap, laminated metal cap, continuous screw cap or any other conventional form of metal cap or polymer cap suitable for closing the bottle or jar. A package is normally provided between the container body and the closure. This package can be used to carry the composition of the invention (in particular, as a polymer matrix containing composition) either as a mixture in the packaging composition or as a separate component applied to the packaging but it is possible that the composition, the invention is used elsewhere in the closure or in another place in the container. In that case, the packaging forming composition may be any conventional, non-altered composition suitable for forming the package. When the closure is a lid, the present scavenging composition can form a total package or a "portion of a total package." This is typically true for small diameter caps such as those smaller than 50 mm in diameter, for large diameter caps The package is a ring-like package and can be deposited in a conventional manner from the packaging forming composition For example, a ring-like package can be formed into a lid by being applied in liquid form as a ring and then can be converted to a ring. solid form by drying, heating to cure or cooling to harden a thermoplastic, as appropriate.The oxygen scavenging composition could be mixed into the packing material, deposited on the packing material, or applied to an area of the cover not covered by the packaging (the central panel) The composition of the packaging formation, for this purpose, may be a dispersion, latex, plastisol, dry mix, appropriate thermoplastic composition or organic solution. The lid, which bears the package, is then pressed to one side d? Proper sealing around the open end of the filled and closed container body in a conventional manner,. If the composition is formed with a thermoplastic polymer matrix, it could be applied as a low viscosity melt while the lid is being spun, so as to pull the composition into the shape of a ring, or can be used as a ring. applied as a melt that is then molded into the desired configuration, often a disk having a thickened ring-like portion. In addition, the package may be in the form of a pre-formed ring or disc that is retained (eg, by mechanical or adhesive means) within the cap. If the closure is a can end, the oxygen scavenging composition is typically not used in the packaging composition because, under typical conditions d? Boat stitching, packaging is not substantially exposed to oxygen in the package. Also, seams are not particularly vulnerable to entry d? oxygen. The oxygen scavenging composition is typically applied in a central panel or other inner surface of the can, such as applied as a coating of a can. It is particularly preferred that the package or coating in the container closure is formed by applying a fluid or molten composition of the present invention formed with a fluid polymer matrix and solidifying it on the closure. The method of application and solidification is generally conventional. S? it particularly prefers that the container and the can end should both be made of metal or the container body should be made of glass and the closure of metal or plastic, since the "use of the compositions defined to form the package then to give particularly beneficial results." In particular, excellent results can be achieved when the container body is a glass bottle and the TS closure is a metal cap. of or in addition to using the fluid or meltable polymer matrix composition of the invention to form a package, it is possible to deposit the composition elsewhere on the internal surface of the closure. It can be applied as a total coating to the internal face d? The closure panel can be applied on only part of the inside face, in particular, when the panel includes one or more push or pull components defined in the panel by discontinuities or lines of weakness, the composition can be applied mainly to cover only the discontinuity or line of weakness, for example a type of closure, usually a boat end, includes at least one, and often two, push components that are defined by partial marking lines through the metal panel so that the pressure of the finger can push a circular area of the panel towards the container, so as to allow access to the contents of the container . In this way, there can be a small thrust component F to allow pressure release and a larger thrust component to allow the liquid to be poured from the container. Said system is described, for example, in DE 3,639,426. In particular, the composition of the first embodiment of the present invention can be deposited as an annular crown (or a disc) that covers the line of weakness. The line d? weakness can be simply? a weakened line in the metal panel, but may be a total cut F around the push component, for example as in DE 3,639,426, in which case the push component generally has a slightly larger area than the opening in the panel which is defined by the cutting line and the composition of the invention can then form a seal between the pushing component and the rest of the closure panel. In all cases where pushing or pulling components are going to form inside the metal panel, there is a serious risk d? What? the formation of the push or pull components can damage the polymer lacquer coating that is generally present on the inner surface of the metal panel. This can expose the metal to corrosion. The application of a composition of the present invention to a container as described herein can both inhibit the corrosion of the metal container as well as improve the storage stability of the contents of the container, especially contents, which contain water, such as beer. . In addition to using metal, glass and plastic containers, the compositions can be used in a cardboard or laminate container such as a juice box. Said container is a cardboard box or tube with an inner coating. The composition can be placed on or laminated to the inner lining of the carton pack, along a line of weakness in the pack closure, or at any other convenient location in the pack. Alternatively, the present composition can placed inside the container like a film, mat or sack. Additionally, the composition of the present invention can be compounded and extruded, injection molded or thermoformed to the desired configurations when the polymer matrix TS a thermoplastic resin. For example, the present compositions can be formed into films themselves or as a >; component of a film composition used to prepare flexible packaging, such as bags, or the films can be laminated to material d? metal that can then be formed into cans and closures. Also, the compositions may be included in flexible packaging such as films or laminates of multiple layers or as a lath, patch, label or coating on a thermoplastic bag or lid material. When the present composition is part? d? a multilayer film, F the formed layer of the present composition can be the surface layer which will be exposed to the inner surface of the resulting flexible package or an inner layer which is covered by a surface layer having sufficient permeability to allow the and moisture penetrating into and contacting the layer containing the present composition. In this way, the term "exposed to the interior", as used herein and in the appended claims, will mean exposure and F whether direct or indirect of the present composition to the internal atmosphere of a sealed container having packaged product contained therein. same. The compositions can also be used in conjunction with or as a portion of an obvious rape membrane for pharmaceuticals and foods.

The following examples are provided for illustrative purposes only and F is not intended to be a limitation on the teachings herein or on the appended claims thereto. All parts and percentages are weight unless manifested otherwise. To test the sweeping ability d? oxygen, each sample was tested in triplicate by being placed in gas-tight, vacuum-sealed containers equipped with a diaphragm to allow gas to be introduced and samples of ST gas to be removed for periodic F analysis. The containers having a sample were injected with 100 cc of ambient air (approximately 20.6% d? 02) and pasteurized at 60aC for 45 minutes and then stored in the dark to avoid photo oxidation. The higher oxygen concentration was measured at regular intervals by withdrawing samples that were then analyzed using a MOCON8"9 Model HS-750 Superior Oxygen Analyzer All samples were prepared and tested in triplicate and the data was averaged F to obtain the values reported.

Example I Preparation of bisulfite-functional hydrotalcite Under a nitrogen atmosphere, 45 parts of - ei - Sodium bisulfite was dissolved in 255 parts of deionized water that had previously been purged with argon. To this ST solution they added 20 parts of an uncalcined hydrocarbonite, functional carbonate with an Mg / Al ratio of 1.0 ([Mg.5Al.5 (OH) 2] (CD3) .25 'XH20) (from Alcoa, HTC-10L). The suspension was stirred for 1 hour under argon with heating at about 60 ° C. The solids were then collected by vacuum filtration under an argon atmosphere and ST washed with 600 parts of deoxygenated water, purged with nitrogen. Long the solids were taken in 300 parts of water purged with argon and stirred for 1 hour before filtering again and washing with 1500 parts of water purged with nitrogen. The product was dried in a vacuum oven at 80 aC for 6 hours to provide a white fine powder. This ST product labeled "HTLC Bisulfite I".

Example II 'A series d was made? samples introducing 0.2 parts of HTLC / Bisulfite I of Example 1 into gas-impermeable sacks of 7.62 cm by 10.16 cm followed by the addition of a transition metal salt in the amount indicated in Table 1 below (all salt additions) they were equimolarßs in metal ion).

The bags were equipped with diaphragms and sealed thermally under vacuum. O.2 parts of water were introduced into each bag followed by 100 cc of air through the diaphragms. The oxygen content of each bag was measured at regular intervals then by removing 3 cc samples from the atmosphere in the bags through the gas syringe and injecting into the Superior 02 MOCON (R) analyzer model HS750. Samples without added water were also monitored to test the stability in air; these dry samples did not show significant sweep. ' Table 1 Soluble Transition Metal Catalyst Test Description Quantity Sweep Oxygen 1 hour or 2 days or 7 days (g) mol / g mol / g or mol / g, HTLC Control Bisulfite I 313 + 0 616 + 61 616 + 62 1 Manganese Sulphate Monohydrate (II) 0.011 313 + 45 659 + 44 715 + 25 2 Sulfate Heptahydrate d? Iron (II) 0.018 372 + 26 682 + 66 766 + 45 3 Pentahydrate1 d? Iron Sulfate (III) 0.032 469 + 22 721 + 77 760 + 80 Iron Chloride (II) Tetrahydrate 0.013 290 + 67 759 + 63 850 + 58 Hexahydrate d? Iron Chloride (III) 0.017 417 + 13 640 + 38 703 + 43 Nickel (II) Sulphate Hexahydrate 0.017 298 + 47 687 + 55 771 + 70 Copper Sulfate Pentahydrate (II) 0.016 253 + 100 549 + 60 787 +34 Copper Chloride (I) 0.006 413 + 16 727 + 30 769 + nd Double the molar amount of metal ion was used.

The above data show that the presence of transition metal salt increased the activity and oxygen capacity d? The anionic hydrotalcite to provide improved systems d? sweep d? oxygen.

Example III A series of samples were made in which a portion of the magnesium ions of the hydrotalcite was exchanged in ions with transition metal ions to produce an anionic HTLC rich in d ion. transition metal. Under a nitrogen atmosphere, 1 part of a transition metal salt was introduced into 85 parts of deionized water, purged with argon and stirred until dissolved. To this solution, 20 parts were added? of a 'uncalcitrated carbonate functional hydrotalcite (Mg / Al ratio of 1.0; [Mg0.5Al0.5 (OH) 2] (C03) 25? 20] (HT'C-10 Alcon) ST added and the suspension warmed at 95 aC for one hour while stirring under argon.The suspension was allowed to cool to 40 ° C and then 15 parts of sodium bisulfite was added to the suspension.The suspension was again heated to 95 C and maintained at that temperature for One hour The suspension was then allowed to cool to room temperature The suspension was filtered under vacuum under a nitrogen atmosphere and washed with 500 parts of water purged with nitrogen to remove the magnesium salt byproduct. it was dried in a vacuum oven at 80 C for about 6 hours Table 2 provides the identity and amount of transition metal salt used, the product yield exchanged in ion, and the amount of transition metal (d? salt) and sulfur (from the F bisulfite) analyzed by means of ICP.

Table 2 ICP Analysis Description Product Salt d? Metal S Metal Ion Me- Trans. (% in such of Trans (% by weight) Trans of HTLC / weight) Used Bisulfite Part Parties Monohydrate of 17.4 1.17 + 0.07 4.6 + 0.4 Manganese Sulfate (II) Heptahydrate of 17.9 0.70 + 0.03 4.6 + 0.2 Sulfate d? Iron (II) P? Ntahydrate d? 17.0 0.137 + 4.75 + Iron Sulfate 0.003 0.09 (III) Tetrahydrate 17.4 0.97 + 0.02 4.9 + 0.1 Iron Chloride (II) H? Xahidrate 0.136 + 4.64 + Iron Chloride 0.003 0.09 (III) Hexahydrate 17.4 1.10 + 0.02 .8 + 0.1 Nickel (II) Sulphate Phenyl Hydrate of 1.21 + 0.02 5.4 + 0.1 Copper Sulphate (II) Copper Chloride (I) 21.1 2.68 + 0.05 7.7 + 0.2 Chloride dihydrate d? Copper (II) 1 18.6 1.69 + 0.03 5.4 + 0.1 Tin Sulfate 1 18.4 1.70 + 0.03 4.73+ (II) 0.09 Sulfate Hydrate1.2227 1.01 + 0.02 7.6 + 0.2 Cobalt (II) 1 HTC-10 used in 240 parts / Bisulfite d? Sodium used in 180 parts.

EXAMPLE IV Preparation of functional bisulfite hydrotalcite Under a nitrogen atmosphere, 90 parts of sodium bisulfite were dissolved in 510 parts of deionized water which had previously been purged of oxygen with nitrogen. To this solution were added 100 parts of uncalcined HTLC acetate, which has a leaf-like morphology and the formula [Mg.7SAl.25 (OH) 2] (02CCH3) .2S • xH20 (obtained from LaRoche Industries, Inc. ). The suspension was stirred for 1 hour under nitrogen, and then the solids were collected through vacuum filtration under an atmosphere d? nitrogen. The material was taken in 600 parts of deionized water purged with nitrogen and stirred for 1 hour. The solids were collected again through vacuum filtration and washed with 6000 parts of water purged with nitrogen. The material was dried for 9 hours at 80 aC in a vacuum oven to provide approximately 60 parts of a fine white powder labeled HTLC / Bisulfite II, ST prepared a series of oxygen scavenging systems from the HTLC / Bisul phyte II above forming a physical mixture of HTLC / Bisulfite II with a cobalt compound in amounts indicated in Table III. The amount used was based on the amount required to react with 20.6 ce of oxygen in the test sacks. In each case where the transition metal is part of the oxygen scavenging system formed, oxygen was rapidly consumed within the first hour of testing. The ST results provide in Table III below.

Table 3 Catalysis of Co (II) Soluble Oxidation of (Bi) Sulphite of Hydrotalcite Test Description% of 1% of 1 CAPACITY week week @ 1 week Capaci- Capaci- (mL 02 / g) dad @ dad @ 1 Hour 1 Hour HTLC / Bisul phito II control 23 95 31.0 1 HTLC / Bisulfite II Similar to sheet + 2 HTLC / Bisulfite II Similar to sheet + 0.5% CoSQ4 84 96 30.1 3 HTLC / Bisulfite II Similar to sheet + 5% Vit B «73 99 31.1 Example V Co: To the leaf-like hydrotalcite exchanged with bisul phyte Example 6 of the U.S. Patent. 5,518,704 (Aristech Chemical Corporation) was modified as follows. 15.13 g of pseudobohmite (Versal 700, LaRoche) and 13.7 g of acetic acid were suspended in 500 mL of water in a 3 L flask equipped with a condenser and then heated at 55 aC for 30 minutes with stirring. 40.9 g of Co (OH) 2 were added to the suspension followed by 1.5 L d? water purged with nitrogen. The mixture was heated at 90 ° C for 6 hours under argon and then cooled to room temperature. The suspension was extremely difficult to filter under vacuum and thus rotatively evaporated at 60 ° C to a thick mud. A portion of it was partially dried in a vacuum oven at 80 aC. 25 g of this crude product was placed in a solution purged with argon of 22.5 g of sodium metabisulfite? 127.5 g of water and ST stirred overnight. The suspension was vacuum filtered, rinsed with 1 L of water, and dried in an oven d? vacuum at 80aC for 6 hours to provide 2.5 g of a purple powder.

Example VI Mg: Al: Co-hydrotalcite sheet-like exchanged with bisul phyte. 7.75 g of pseudobohmite (Versal 700, LaRoche) and 6.85 g of acetic acid were suspended in 500 mL of water in a 3 L flask equipped with a condenser and then heated at 55 aC for 30 minutes with stirring. 8.41 g of Mg (OH) 2 (MagChem-325, Martin Magnesia Specialties) and 1.02 g of Co (OH) 2 were added to the F suspension followed by 750 mL of water purged with nitrogen. The mixture was heated at 90 ° C for 6 hours under nitrogen and then allowed to cool to 40 ° C. 36.0 g of sodium bisulfite were added and stirred for 1 hour. After resting overnight, the suspension had partially settled. It was easily filtered under vacuum and washed with 2 L of water. The yield of the purple powder after drying in the vacuum oven at 80 aC for 6 hours was 19.4 g.

Example VII The samples exchanged with ions of Examples V and VI were tested for oxygen-absorbing capacity according to the procedure of Example IV above. The results showed very rapid oxygen scavenging by the materials exchanged with ions as shown in Table IV below.

Table 4 Co (II) -Containing Hydrotalcite Bisulfites with Morphology Similar to Leaf DESCRIPTION% of 1% of 1 CAPACITY Week Week @ 1 week CapaciCapaci (mL 02 / g) dad @ dad @ 1 hour 1 hour Co: To the Bisulfite of Hydro- 96 100 38.8 similar to Mg Sheet: Co: To the Bisulfite of 97 100 21, 9 Hydrotalcite similar to Leaf

Claims (9)

1. - An oxygen scavenging composition comprising a carrier having substantially distributed therein a combination of a hydrotalcite-like material and a transition metal compound, the hydrotalcite-like material being present at 0.05 to 90 percent in weight of the composition and represented by the formula: - wherein M1 represents an alkali metal selected from sodium or potassium; Mp represents magnesium, zinc, nickel, copper, cobalt and mixtures thereof; M? P represents aluminum, chromium, iron and mixtures thereof; A represents an anion, at least 60 per F molar of the oxygen scavenging anion compound selected from bisulfite, dithionite, ascorbate, thioylate, phylolate or mixtures thereof; x TS a numerical value d? approximately 0.1 to 0.5; a is a numerical value average of the valence of a, and represents O when "a" TS less than 2 and a value of 0 to 0.5 when "a" TS at least 2; and n is a numerical value from 0 to 4; F '. and the transition metal compound is present in an amount such that the molar ratio of HSM to transition metal is from 3000: 1 to 1: 1. 2.- The composition d? according to claim 1, wherein the transition metal compound has a transition metal selected from Se, Ti, V, Cr, Mn, Fe, Co, Ni, Sn, Cu or mixtures thereof. 3. The composition according to claim 2, wherein the transition metal is selected from Co, Cu, Fe or mixtures thereof. The composition according to claim 1. wherein the oxygen scavenging anion A is selected from ascorbate anion, thiolate anion, phenolate anion or mixtures thereof 5. The composition according to claim 2, wherein the anion The oxygen scavenger is selected from ascorbate duct, thiolate anion, phenolate anion or mixtures thereof 6. The composition according to claim 1, wherein the oxygen sweeping anion TS bisulphite, dithionate or mixtures thereof 7 - The composition according to claim 2, wherein the oxygen sweeping anion A is bisulfite, dithionate or mixtures thereof 8. The composition according to claim 4 , where the anion A sweeping oxygen eno is an ascorbate anion 9.- The composition d? according to claim 5, wherein the oxygen scavenging anion A is an ascorbate anion. 10. The composition according to claim 1, wherein the carrier is a thermoplastic resin selected from the group consisting of polyethylene, ethylene / vinyl acetate copolymers, sodium chloride homopolymers. vinyl, vinyl chloride copolymers and mixtures thereof. 11. The composition according to claim 5, wherein the carrier is a thermoplastic resin selected from the group consisting of polyethylene, copolymers of ethylene / vinyl acetate, homopolymers of vinyl chloride, copolymers of vinyl and mixtures thereof. 1

2. The composition according to claim 7, wherein the carrier is a thermoplastic resin selected from the group consisting of polyethylene, ethylene / vinyl acetate copolymers, vinyl chloride homopolymers. copolymers? chloride d? vinyl and mixtures thereof. 1

3. The composition according to claim 1, wherein the carrier is a polymer matrix comprising polyethylene not selected from the group consisting of in linear polyethylenes of high, low, very low, ultra low and low density, mixtures thereof and mixtures of polyethylene with other polymers. 1

4. The composition according to claim 1, wherein the carrier is a polymer matrix comprising a mixture of at least one polyethylene and at least one ethylene / vinyl acetate copolymer. 1

5. The composition according to claim 1, where? the carrier is a polymer matrix comprising a polymer selected from the group consisting of polyolefin, ethylene / vinyl acetate copolymer, butyl rubber, styrene / butadiene rubber, styrene / butadiene block copolymers / styrene, isoprene, styrene / isoprene / styrene block copolymers, styrene / ethylene / butylene / styrene block copolymers, and mixtures thereof. 1

6. The composition according to claim 1, wherein the carrier is a polymorphic matrix comprising an epoxide, phenolic. polyurethane, polyvinyl chloride homopolymer, polyvinyl chloride copolymers and mixtures thereof. 1

7. A product that is a container having a suitable interior cavity for containing an oxygen-sensitive material that has, as when it is part of the container and exposed to the interior of the container, the composition according to claim 1. A product that is a container having a suitable interior cavity for containing an oxygen sensitive material that has, as at least part of the container and exposed to the interior of the container, the composition in accordance with. claim 2. 19. A product that is a container having an interior cavity suitable for containing an oxygen sensitive material having, as at least part of the container and exposed to the interior of the container, the composition according to claim 5. 20. A product that is a container having an interior cavity suitable for containing an oxygen sensitive material having, as at least part of the container and exposed to the interior of the container, the composition according to claim 7.