JP2016505642A - Coating composition, cured coating, and method of making and using the same - Google Patents

Abstract

Disclosed is a coating composition comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid. A cured coating formed from the coating composition is also disclosed. Further disclosed is a method of making and using a coating composition comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid. [Selection] Figure 1

Description

  [0001] The present invention relates to a coating composition, particularly a polyvinyl alcohol (PVOH), a coating composition comprising one or more metal alkoxides, and a reaction product of an organic acid, and a cured coating formed from the coating composition, and It relates to a method of manufacturing and using it.

  [0002] Food and beverage packaging materials are known. Such food and beverage packaging materials typically provide the desired amount of gas barrier performance to protect the food packaged therein. Traditionally, thermoplastic resins such as polypropylene have been used to provide gas barrier properties.

  [0003] Polyvinyl alcohol (PVOH) is known to provide high gas barrier performance among thermoplastic resins. However, PVOH has poor gas barrier performance in high humidity environments due to the presence of hydroxyl groups that attract water. Many attempts have been made to improve the performance of PVOH. For example, methods for producing PVOH-ethylene copolymers in Japanese Patent Application 2006-219518 and US Patent 7,435,446; silicon in Japanese Patent Application 2010-89321, US Patent 7,341,782, and US Patent 7,763,335 See a method using a sol-gel reaction with an alkoxide and polyvinyl alcohol; and a method using an esterification reaction between PVOH and acrylic acid in Japanese Patent Application 2008-36914 and US Pat. No. 7,524,900.

Japanese Patent Application 2006-219518 US Patent 7,435,446 Japanese Patent Application 2010-89321 US Patent 7,341,782 US Patent 7,763,335 Japanese Patent Application 2008-36914 US Patent 7,524,900

  [0004] Although efforts have been made to improve the performance of PVOH as a gas barrier, the known approaches do not provide a coating composition that has both water resistance and gas barrier properties; The method used to form the object requires the use of unstable reactants; the method used to form the coating composition requires the use of one or more inorganic acids (eg, HCl). And / or the film obtained from the coating composition has one or more drawbacks such as (but not limited to) being too cloudy to be used as a food packaging material component.

  [0005] Efforts continue in the development of coating compositions that include a reaction product of PVOH that provides both water resistance and very good gas barrier properties even at relatively high humidity conditions.

  [0006] The present invention continues efforts to develop a coating composition that includes a reaction product of PVOH that provides both water resistance and very good gas (eg, oxygen) barrier properties. In particular, the present invention relates to a coating composition comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid.

  [0007] In one exemplary embodiment of the present invention, the coating composition comprises a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid, the coating composition optionally comprising a colorant. One or more optional additives such as In some desirable embodiments, the polyvinyl alcohol comprises hydrolyzed polyvinyl alcohol, the one or more metal alkoxides comprise methyltrimethoxysilane, tetraethoxysilane, or combinations thereof, and the organic acid comprises at least one carboxylic acid. Contains low molecular weight organic acids containing acid groups.

[0008] The present invention further includes the disclosed coating composition, wherein the coating composition is heated to a curing temperature for a period of time to remove all or substantially all of the solvent used to form the coating composition. Relates to the cured coating. The cured coating of the present invention provides very good water resistance and very good oxygen transmission rate (OTR) as measured by a water rub test (discussed below). In some exemplary embodiments, the cured coating of the present invention comprises (i) room temperature water, at least about 20 water resistance as measured using a water rub test, and (ii) 23 ° C. and about It has an oxygen transmission rate of less than 50 cc / m ² / day measured at a relative humidity of less than 50%. In another exemplary embodiment, the cured coating of the present invention comprises (i) water at room temperature, at least about 50 water resistance as measured using a water rub test, and (ii) 23 ° C. and about 80 It has an oxygen transmission rate of less than 50 cc / m ² / day measured at% relative humidity.

  [0009] Another aspect of the invention relates to a coating comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid and having a contact angle of at least 35 °. In other aspects of the invention, the coating has a contact angle of at least 40 °, or at least 45 °.

  [0010] A further aspect of the invention relates to a gas and moisture barrier coating comprising a reaction product of polyvinyl alcohol and one or more metal alkoxides and having a contact angle of at least 35 °. In other aspects of the invention, the coating has a contact angle of at least 40 °, or at least 45 °.

[0011] Another aspect of the invention includes a substrate, and a moisture and gas barrier coating thereon, the coating comprising a reaction product of polyvinyl alcohol and one or more metal alkoxides after being cured. The coating has the following properties: (i) a contact angle of at least 35 °; (ii) water resistance at least about 20 as measured using water rub test using room temperature water; or (iii) 23 ° C. and about 50 Relates to articles having one or more of an oxygen transmission rate of less than 50 cc / m ² / day, measured at a relative humidity of less than 50%. In further embodiments, the coated substrate comprises a film, foil, or sheet. In a further aspect of the invention, the coated substrate further comprises an oxygen scavenging film.

  [0012] The present invention further relates to the disclosed coating compositions and methods of making cured coatings. In one exemplary embodiment, the method of making a coating composition of the present invention comprises forming a mixture comprising polyvinyl alcohol in a solvent; adding an organic acid to the mixture; and one or more metal alkoxides. Adding to the mixture. The method of producing the coating composition (or cured coating therefrom) can further include the step of curing the coating composition to remove the solvent. In desirable embodiments, the method catalyzes a reaction between (1) (i) a hydroxyl group on polyvinyl alcohol and (ii) one or more metal alkoxides; and (2) (i) on polyvinyl alcohol Using in the mixture an amount of organic acid that allows an esterification reaction between the remaining hydroxyl groups of (ie, hydroxyl groups that have not reacted with one or more metal alkoxides) and the organic acid. .

  [0013] The present invention also relates to the disclosed coating compositions and methods of using the cured coating. In one exemplary embodiment, a method of using the coating composition of the present invention includes the steps of applying the coating composition onto a substrate and curing the coating composition. In some exemplary embodiments, a method of using the coating composition of the present invention applies the coating composition onto a substrate, such as a film, to form a multilayer article that can include an oxygen scavenging layer. The process of carrying out is included.

  [0014] In another exemplary embodiment, a method of using the cured coating of the present invention includes the step of at least partially encapsulating a food product with a cured coating. In some exemplary embodiments, the method of using the coating composition or cured coating of the present invention includes shielding the food product from environmental exposure for long-term storage of the food product.

[0015] These and other features and advantages of the present invention will become apparent after a review of the following detailed description of the disclosed embodiments and the appended claims.
[0016] The present invention will be further described with reference to the accompanying drawings.

[0017] FIG. 1 shows an exemplary coating composition of the present invention coated on a substrate. [0018] FIG. 2 is a cross-sectional view of an exemplary article comprising one or more food items packaged within a food packaging material, wherein an exemplary cured coating of the present invention comprises one component of the food packaging material. Indicates.

  [0019] To facilitate an understanding of the principles of the invention, specific embodiments of the invention are described below, and specific terms are used to describe the specific embodiments. However, it will be understood that the use of specific terms is not intended to limit the scope of the invention. Changes in the principles of the invention that are discussed, further modifications, and such further applications are believed to be normally conceived by one of ordinary skill in the art to which the invention belongs.

  [0020] Further, with respect to the drawings used to describe the invention, it should be noted that some aspects of the invention include one or more of the features shown in the drawings. In some aspects, the invention may actually include one or more of the features shown in the drawings and other features not specifically shown in the drawings. In still other aspects, the invention may actually include one or more of the features shown in the drawings, but may not include other features. Thus, in some aspects of the invention, features not specifically shown in the drawings are specifically excluded from the invention (ie, if a feature is not shown in the drawing, the feature is In some embodiments it is clearly excluded from the present invention).

  [0021] It should be noted that the singular forms "a", "and", and "the" as used in the specification and claims include a plurality of indications unless the description clearly indicates otherwise. It is. Thus, for example, reference to “oxide” includes a plurality of such oxides, and description of “oxide” includes descriptions of one or more oxides and equivalents known to those skilled in the art.

  [0022] For example, the amount, concentration, volume, process temperature, process time, recovery rate or yield, flow rate, and similar values of components in compositions used in the description of some embodiments of the invention, and ranges thereof “About” modifying can occur, for example, through normal measurement and handling procedures; through accidental errors in these procedures; differences in the components used to perform the method; and similar approximate considerations; Refers to changes in quantity. The term “about” also encompasses amounts that vary with time for a formulation or mixture having a particular initial concentration, as well as amounts that vary with the mixing or processing of a formulation or mixture having a particular initial concentration. The claims encompass equivalent ranges of these quantities, whether modified by the term “about” or not.

  [0023] The term "polyvinyl alcohol" as used herein refers to a polymer having a degree of polymerization in the range of about 300 to about 5000. This is produced by polymerizing vinyl acetate and then partially hydrolyzing. The hydrolysis process is based on partial replacement of ester groups in vinyl acetate with hydroxyl groups and is completed in the presence of aqueous sodium hydroxide. After adding the aqueous saponifying agent stepwise, the polyvinyl alcohol is precipitated, washed and dried. The degree of hydrolysis is determined by the time when the saponification reaction is stopped. Acetate groups are hydrolyzed by transesterification with methanol in the presence of anhydrous sodium methylate or aqueous sodium hydroxide. The physical properties and their specific functional uses are determined by the degree of polymerization and the degree of hydrolysis.

[0024] As used herein, the term "metal alkoxide" refers to a compound of an inorganic alkoxide precursor (in most cases the formula M (OR) _n, where M is silicon, or Al, Ti, or Zr N represents the valence of the element M; n groups: -OR is defined as an alkoxide) of the same or different organic group, for example an alkoxy group). Such compounds may include silicon and alcohols of the general formula: Si (OR) ₄ where R is one or more different alkyl groups.

[0025] An "organic acid" as used herein is defined as an organic compound (eg, containing carbon) having acidic properties. Most ordinary organic acids are carboxylic acids whose acidity is related to their carboxyl group: —COOH (eg, formic acid, acetic acid, lactic acid, citric acid, propionic acid, valeric acid, oxalic acid, merit acid, etc.) . The sulfonic acid containing group: —SO ₂ OH is a relatively strong acid. Alcohols having —OH can act as acids, but they are usually very weak. The acidity is determined by the relative stability of the acid conjugate base. Also, other groups, thiol groups: -SH, enol groups, and phenol groups can usually give weak acidity. In biological systems, organic compounds containing these groups are generally called organic acids.

  [0026] The present invention relates to a coating composition comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid. The present invention further relates to a cured coating (eg, a film) comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid. The invention further relates to the disclosed coating compositions and methods of making and using the cured coatings.

  [0027] In one exemplary embodiment, the coating composition of the present invention comprises (i) a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid, and optionally (ii) one type. Contains the above optional additives. Suitable optional additives include, but are not limited to, colorants, inorganic nanoparticle fillers, crosslinking agents, antioxidants, adhesion promoters, oxygen scavengers, or combinations thereof. If present, each additive can be present in any amount, but is usually based on the total weight of solids in the coating composition (or of the cured coating formed from the coating composition). Present in an amount of about 5.0 weight percent (wt%) or less (or greater than 0 wt% to about 3.0 wt%; or greater than 0 wt% to about 1.0 wt%) (based on total weight) Let

  [0028] The coating composition of the present invention usually further comprises a solvent system, at least during the formation of the coating composition. Suitable solvents for certain coating compositions of the present invention can include, but are not limited to, water (eg, deionized water), methanol, ethanol, ethylene glycol, 2-propanol, or combinations thereof. In one exemplary embodiment, the coating composition includes a solvent comprising deionized and ethanol in a 1: 1 weight ratio.

  [0029] In a preferred embodiment of the present invention, the polyvinyl alcohol used to form the reaction product in the coating composition of the present invention comprises hydrolyzed polyvinyl alcohol. As used herein, the term “hydrolyzed” polyvinyl alcohol is used to denote polyvinyl alcohol in which at least about 90% of the acetate groups on the raw material polyvinyl acetate used to form the polyvinyl alcohol are hydrolyzed. . Typically, the hydrolyzed polyvinyl alcohol used in the present invention is at least about 90% (or about 91%, or about 92%, or about 93% of the acetate groups on the raw material polyvinyl acetate used to form the polyvinyl alcohol. Or about 94%, or about 95%, or about 96%, or about 97%, or about 98%, or about 99%, or 100%). This makes it possible to make polyvinyl alcohol soluble in the reaction medium.

  [0030] Further, the polyvinyl alcohol used to form the reaction product in the coating composition of the present invention typically comprises polyvinyl alcohol having a degree of polymerization in the range of about 300 to about 5000. In desirable embodiments, the polyvinyl alcohol used to form the reaction product in the coating composition of the present invention has a degree of polymerization in the range of about 400 to about 4000 (or about 450 to about 2000; or about 470 to about 1800). Or any degree of polymerization between about 300 and about 5000).

  [0031] In one desirable embodiment of the present invention, the polyvinyl alcohol used to form the reaction product in the coating composition is a hydrolyzed polyvinyl alcohol having a degree of polymerization in the range of about 470 to about 1800 (eg, 95 %).

  [0032] A number of commercially available polyvinyl alcohols can be used to form the reaction products in the coating compositions of the present invention. Suitable commercially available polyvinyl alcohols are commercially available from Nippon Synthetic Chemical (city, state, country), with hydrolysis having a degree of polymerization of 1800 (98-99% mol% hydrolysis) PVOH. OKS-1081, which is commercially available from Nippon Synthetic Chemical (city, state, country), and has a degree of polymerization of 470 (99.0 to 99.6% mol% hydrolysis) PVOH is OKS 8049; PVA105 which is commercially available from Kuraray America, Inc. (Houston, TX) and has a degree of polymerization of 500 (98-99% mol% hydrolysis) PVOH; and Kuraray America, Inc. ( EXCEVAL® HR-3010 which is a commercially available hydrolysis (99.0-99.6% mol% hydrolysis) PVOH-ethylene copolymer from Houston, TX), but is not limited thereto. .

  [0033] The one or more metal alkoxides used to form the reaction product in the coating composition of the present invention may comprise any metal alkoxide. In one embodiment of the present invention, the metal alkoxide includes silicon alkoxide. Suitable silicon alkoxides for use in the present invention include, but are not limited to, methyltrimethoxysilane, tetraethoxysilane, vinyltrimethoxysilane, glycidoxypropyltrimethoxysilane, or any combination thereof. . In one exemplary embodiment, the one or more silicon alkoxides used to form the reaction product in the coating composition of the present invention include methyltrimethoxysilane, or tetraethoxysilane, or combinations thereof. . In another exemplary embodiment, the one or more silicon alkoxides used to form the reaction product in the coating composition of the present invention comprises tetraethoxysilane.

  [0034] A number of commercially available silicon alkoxides can be used to form the reaction products in the coating compositions of the present invention. Suitable commercially available silicon alkoxides include methyltrimethoxysilane commercially available under the trade name KBM-13 from Shin-Etsu Chemical (Tokyo, Japan); Shin-Etsu Chemical Co., Ltd. under the trade name KBE-04. Tetraethoxysilane (TEOS) from numerous suppliers; vinyltrimethoxysilane commercially available from Shin-Etsu Chemical under the trade name KBM-1003; and commercially available from Shin-Etsu Chemical under the trade name KBM-403 Glycidoxypropyltrimethoxysilane which can be, but is not limited to.

  [0035] The coating composition of the present invention is formed from PVOH using one or more metal alkoxides (MA) and one or more metal alkoxides used, and a coating composition. The PVOH / MA ratio (ie, “MA” is one or more present in the coating composition) may vary depending on a number of factors such as (but not limited to) the desired final properties in the cured coating Represents the total amount of the metal alkoxide. Typically, the coating composition of the present invention comprises the above-described polyvinyl alcohol (PVOH) and one or more metal alkoxides (MA) at about 9/1 (ie, 1 part by weight of one or more metal alkoxides). 9 parts by weight PVOH) to about 5/5 PVOH / MA ratio. In some exemplary embodiments, the polyvinyl alcohol (PVOH) and the one or more metal alkoxides (MA) are present at a PVOH / MA ratio of about 8/2 to about 7/3.

  [0036] The organic acid used to form the reaction product in the coating composition of the present invention can include any organic acid. Suitable organic acids for use in the present invention include, but are not limited to, low molecular weight organic acids. As used herein, the term “low molecular weight organic acid” is used to refer to an organic acid having a molecular weight of less than 120 grams per mole of organic acid. In some embodiments, the organic acid used to form the reaction product in the coating composition of the present invention comprises a carboxylic acid. In some desirable embodiments, the organic acid used to form the reaction product in the coating composition of the present invention comprises a carboxylic acid selected from formic acid, acetic acid, propionic acid, or combinations thereof.

  [0037] The present invention further relates to a method of making a coating composition. In one exemplary embodiment, the method of making the coating composition of the present invention forms a mixture comprising polyvinyl alcohol in a solvent; an organic acid is added to the mixture; and then one or more metal alkoxides are added. Adding to the mixture. As discussed above, in a preferred embodiment, the method catalyzes a reaction between (1) (i) a hydroxyl group on polyvinyl alcohol and (ii) one or more metal alkoxides; and (2 ) (I) any remaining hydroxyl groups on the polyvinyl alcohol (ie, hydroxyl groups that have not reacted with one or more metal alkoxides) (eg, any proportion of the remaining hydroxyl groups, preferably the remaining hydroxyl groups Between a large proportion (> 50%, or> 60%, or> 70%, or> 80%, or> 90%, or> 95%) or all of the remaining hydroxyl groups) and (ii) the organic acid Using an amount of an organic acid in the mixture that enables the esterification reaction of

  [0038] The amount of each reactant and solvent can be varied in the coating composition of the present invention, but typically the polyvinyl alcohol is about 5% to about 20% by weight (pbw) of the coating composition. Present in a given coating composition in an amount in the range; the one or more metal alkoxides are present in an amount ranging from about 1% to about 20% pbw of the coating composition; the organic acid is about 1% of the coating composition. The solvent is present in an amount ranging from about 60% to about 95% pbw of the coating composition; where all parts by weight represent the total weight of the coating composition. It is a standard.

  [0039] In some embodiments, the polyvinyl alcohol is present in an amount ranging from about 5% to about 20% pbw of the coating composition; one or more metal alkoxides are from about 1% to about 20 of the coating composition. Present in an amount in the range of about 1% to about 10% pbw of the coating composition; the solvent in the range of about 60% to about 95% pbw of the coating composition. Present, in which all parts by weight are based on the total weight of the coating composition. Regardless of the amount of each component, as discussed above, in desirable embodiments, the coating composition has a PVOH / SA ratio of about 9/1 to about 6/4 or 5/5, more preferably about 8 A PVOH / SA ratio of from / 2 to about 7/3.

  [0040] The method of making the coating composition of the present invention can further include applying the coating composition onto a substrate, such as any substrate suitable for the food packaging industry. The coating composition can be applied onto a given substrate using any known coating method. Furthermore, the coating composition can be applied on any given substrate. In one exemplary embodiment, the coating composition is applied over a substrate that includes a film. Such a representative embodiment is shown in FIG.

  [0041] A representative coating composition 10 of the present invention is coated on an outer surface 21 of a substrate 20, as shown in FIG. In this embodiment, the substrate 20 includes a film. However, exemplary coating compositions 10 may include polymer substrates, paper substrates, metal foil substrates, fabrics, hard surfaces (eg, glass, wood, stone, etc.), or any other substrate (but these It should be understood that any number of different types of substrates can be applied (but not limited to).

  [0042] In some embodiments, the coating composition includes (1) polyvinyl alcohol, (2) one or more metal alkoxides, (3) an organic acid, (4) a solvent system, and (5) discussed above. It should be understood that one or more optional additives may be included. In other embodiments, the coating composition comprises (1) polyvinyl alcohol, (2) one or more metal alkoxides, (3) an organic acid, (4) a solvent system, and (5) one or more as discussed above. From the optional additives. As used herein, the term “substantially composed” is used to describe a coating composition that may unintentionally contain some residual component, such as one or more impurities. In other embodiments, the coating composition comprises (1) polyvinyl alcohol, (2) one or more metal alkoxides, (3) an organic acid, (4) a solvent system, and (5) one or more as discussed above. Of optional additives.

  [0043] Further, in the method of making the coating composition of the present invention, the coating composition is cured to remove the solvent (eg, water, ethanol, or combinations thereof) to provide the cured coating of the present invention. Can be further included. While the curing process can include various parameters (eg, temperature and time), typically the curing process is a mixture or coating composition or coated composition (ie, already coated on a substrate). Heating to a temperature of at least 50 ° C. for a time of at least about 30 minutes. In other embodiments, the curing step may include subjecting the mixture or coating composition or coated composition (ie, already coated on a substrate) to a temperature of about 50 ° C. to about 140 ° C. for about 5 minutes to about 30. Heating for a time in the range of minutes (or a time in the range of about 2 minutes to about 10 minutes to about 100 ° C. to about 140 ° C.).

  [0044] The resulting cured coating typically contains up to 100% by weight of a reaction product formed from polyvinyl alcohol, one or more metal alkoxides, and an organic acid. As discussed above, the cured coating can include one or more optional additives. Typically, the cured coating comprises about 70-100% by weight of a reaction product formed from polyvinyl alcohol, one or more metal alkoxides, and an organic acid, and about 30% to 0% by weight of one or more. Additives, more usually about 85-100% by weight of a reaction product formed from polyvinyl alcohol, one or more metal alkoxides and an organic acid, and about 15% to 0% by weight. Contains the above additives.

  [0045] (i) a first reaction between a hydroxyl group on the polyvinyl alcohol and one or more metal alkoxides; and (ii) a second reaction between the remaining hydroxyl groups on the polyvinyl alcohol and the organic acid. The reaction product obtained from the esterification reaction is believed to have a molecular structure similar to that of the PVOH polymer. In other words, the resulting reaction product has very little, if any, inorganic polymer chains formed from one or more metal alkoxides.

  [0046] In some embodiments, the cured coating comprises (1) (i) polyvinyl alcohol, (ii) one or more metal alkoxides, and (iii) a reaction product of an organic acid, and (2) the above One or more optional additives discussed in 1. can be included. In other embodiments, the cured coating comprises (1) (i) polyvinyl alcohol, (ii) one or more metal alkoxides, and (iii) a reaction product of an organic acid, and (2) one of the types discussed above. It can consist essentially of the above optional additives. As used herein, the term “substantially composed” refers to one or more impurities, one or more solvent components (eg, trapped within the coating thickness), one or more unreacted reactants. Or a cured coating that may unintentionally contain some residual component, such as any combination thereof. In other embodiments, the cured coating comprises (i) polyvinyl alcohol, (ii) one or more metal alkoxides, and (iii) a reaction product of an organic acid, and (2) one or more optional ones discussed above. It consists of typical additives. Ethanol can be added to the reaction mixture, which controls the size of the particles formed during the reaction. This results in a stable coating composition (ie stable viscosity and long shelf life). Add to claims.

  [0047] The cured coating desirably has a combination of properties that allow the cured coating to be used, for example, as a food packaging material. Two properties used to evaluate the cured coatings of the present invention are (1) water rub test and (2) oxygen transmission rate test (ie OTR test), both of which are in the Examples section below. Describe. Desirably, the cured coatings of the present invention use room temperature water and have a water resistance of at least about 20 as measured using a water rub test. More desirably, the cured coatings of the present invention use room temperature water and have at least about 30 (or at least about 40, or at least about 50, or at least about 60, or at least about 70, as measured using a water friction test. Or at least about 80, or at least about 90, or at least about 100). Desirably, the cured coatings of the present invention also pass a water friction test using heated water (eg, about 60-70 ° C, preferably about 70-80 ° C).

[0048] Further desirably, the cured coatings of the present invention have an oxygen transmission rate of less than 50 cc / m ² / day as measured using the OTR test at 23 ° C. and a relative humidity of less than about 50%. More desirably, the cured coatings of the present invention are less than 45 cc / m ² / day (or about 40 cc / m ² / day, or about 30 cc as measured using the OTR test at 23 ° C. and a relative humidity of less than about 50%. / M ² / day, or less than about 25 cc / m ² / day, or less than about 20 cc / m ² / day, or less than about 15 cc / m ² / day, or less than about 10 cc / m ² / day) Have speed.

[0049] In some exemplary embodiments of the present invention, the cured coating comprises (i) at least about 20 water resistance as measured using water rub test using room temperature water, and (ii) 23 It has an oxygen transmission rate of less than 50 cc / m ² / day measured at 0 ° C. and a relative humidity of less than about 50%. In another exemplary embodiment of the present invention, the cured coating comprises (i) water at room temperature, at least about 50 water resistance as measured using a water rub test, and (ii) 23 ° C. and about 50 It has an oxygen transmission rate of less than 25 cc / m ² / day measured at a relative humidity of less than%. In yet another exemplary embodiment of the present invention, the cured coating comprises (i) water resistance at room temperature as measured using a water rub test using (i) room temperature water, and (ii) 23 ° C. and about It has an oxygen transmission rate of less than 10 cc / m ² / day measured at a relative humidity of less than 50%.

[0050] Desirably, the cured coatings of the present invention provide the desired degree of water resistance and oxygen transmission rate at higher relative humidity conditions. In some exemplary embodiments of the invention, the cured coating comprises (i) water at room temperature, at least about 50 water resistance as measured using a water rub test, and (ii) 23 ° C. and about It has an oxygen transmission rate of less than 10 cc / m ² / day measured at 65% relative humidity. In another exemplary embodiment of the present invention, the cured coating comprises (i) water at room temperature, at least about 50 water resistance as measured using a water rub test, and (ii) 23 ° C. and about 80 It has an oxygen transmission rate of less than 50 cc / m ² / day measured at% relative humidity.

  [0051] Desirably, the cured coating of the present invention has the above properties even though it has a relatively thin coating thickness. For example, in some exemplary embodiments of the present invention, the cured coating has the water resistance and oxygen transmission rate described above when the cured coating has a coating thickness of less than 10 microns (μm). In another exemplary embodiment of the present invention, the cured coating has the water resistance and oxygen transmission rate described above when the cured coating has a coating thickness of less than about 5 μm. In yet another exemplary embodiment of the present invention, the cured coating has the above water resistance and oxygen transmission rate when the cured coating has a coating thickness of less than about 1.0 μm.

  [0052] The present invention further relates to the disclosed coating compositions and methods of using cured coatings. In one exemplary embodiment, a method of using the coating composition of the present invention includes applying the coating composition onto a substrate and curing the coating composition. As discussed above, in some exemplary embodiments, the method of using the coating composition of the present invention comprises applying the coating composition onto a substrate such as a film to form a multilayer article. Including.

  [0053] In another exemplary embodiment, a method of using the cured coating of the present invention includes at least partially encapsulating a food product with a cured coating. In some exemplary embodiments, the method of using the coating composition or cured coating of the present invention includes shielding the food product from environmental exposure to oxygen for long-term storage of the food product. Such use is illustrated in FIG.

  [0054] As shown in FIG. 2, an exemplary article 100 includes one or more food items 40 packaged within one or more food packaging materials 10 and 30, and one or more food packaging materials 10 and 30. At least a portion of which includes a representative cured coating 10 of the present invention. As shown in FIG. 2, the exemplary cured coating 10 has an inner surface 11 and an outer surface 12, while the base container 30 has an inner surface 31, an outer surface 32, and an upper end 33. The food product 40 is supported by the base container 30 (i.e., on the inner surface 31), which may consist of, for example, a paper product, a STYROFOAM® product, or a molded polymer product (eg, a molded polypropylene product). it can. The exemplary cured coating 10 forms a gas barrier along the outer surface 12 between the food product 40 and the environment.

  [0055] The present invention is described above for purposes of illustration and is further illustrated below, but they should not be construed as limiting the scope of the invention in any way. On the contrary, the solution may have various other aspects, modifications, and equivalents thereof, after reading the description herein, from the spirit of the invention and / or the claims. It is clearly understood that it can itself be suggested to one skilled in the art without departing.

  [0056] In the examples below, the following materials shown in Table 1 were used. The metal alkoxide used in the examples is a silicon alkoxide, but any metal alkoxide can be used.

Sample preparation method:
Gas and moisture barrier coating formulations were prepared as follows.
[0057] A solution of PVOH was prepared by mixing 10 g of PVOH in 900 g of deionized water at room temperature using a mechanical disperser. After mixing for 20 minutes, the PVOH dispersion was heated at 95 ° C. for 4 hours, thereby dissolving the PVOH to obtain a solution containing 10 wt% PVOH. Dilute 27 g PVOH solution to 5% by adding 13.5 g DI water, then 1.157 g silicon alkoxide (100%), 1.12 g acid catalyst, and 13.5 g alcohol (95% ) Was added over 10 minutes at room temperature with stirring. The reaction mixture was stirred at room temperature for about 1 hour until the reaction was complete. A stable coating formulation was obtained.

A cured gas and moisture barrier film was prepared as follows.
[0058] Using a pipette, a 10 g / mL coating formulation was applied onto a substrate (polypropylene or PET sheet obtained from Teijin Limited). The coating formulation was developed on a substrate using a coating bar available from KBY to form a film having a wet thickness of 20-80 microns. The coated film was then cured for 3-10 minutes at 100-140 ° C. to form a cured coating / film having a thickness of 1-4 microns.

Test method:
[0059] The following test methods were used in the examples.
Water resistance test:
[0060] For a given cured coating sample, the sample was subjected to various tests to evaluate the water resistance or moisture resistance of the cured coating sample. These tests are described below.

(1) Water friction test (ASTM-D4752):
[0061] The cured coated film prepared in the above sample preparation method was fixed on a glass plate placed on a stable table. A 5 cm × 5 cm white cotton cloth was attached to the finger part of the clock meter using a spinal clip. The cloth on the finger part of the clock meter was lowered onto the coating film. The hand crank was rotated 50 cycles at a speed of 1 revolution per second. The white cotton fabric rubbed with the test fabric was visually inspected for the coating on it and the coated film was inspected to determine if there was a change in appearance and transparency. When the appearance of the cured film was changed, the hand crank was stopped and the cycle number was recorded.

(2) Boiling water test:
[0062] The cured coated film prepared in the sample preparation method described above was immersed in boiling water at 100 ° C. for 20 seconds. The film was then removed from the water and the cured coating surface was visually inspected for defects and tackiness. Next, the film surface was dried at 100 ° C. for 2 minutes. The film was again visually inspected for defects, tackiness, and transparency. A film is characterized as having good water resistance if it has no defects, is not tacky and is transparent.

Oxygen transmission rate test:
[0063] By using the MOCON method (JIS-K7126-2 / ASTM-D3985) for the predetermined cured coating sample prepared in the above sample preparation method, the gas barrier property of the sample is evaluated and the oxygen transmission rate is measured. did. This method is a steady state equilibrium method using a coulometric sensor. In the test, Mocon Oxtran 2/20 commercially available from Mocon, Inc. (Minneapolis, MN, USA) was used. This test is described below.

  [0064] The cured film sample prepared in the sample preparation method described above was cut to form a 10 cm x 10 cm sample and placed in the apparatus. The temperature was set to 23 ° C. and the device was set to converged mode. Air was passed over one side of the sample and nitrogen was passed over the other side. The amount of oxygen permeating through the sample into the nitrogen stream was measured by a sensor. The test was conducted for 24 hours.

Contact angle test:
[0065] Described in US Pat. No. 5,268,733 using the Tantec CAM-Plus contact angle meter available from ChemInstruments International (Mentor, OH, USA) for a given cured coating sample prepared in the above sample preparation method. The surface properties of the sample were evaluated by the half-angle measurement method (ASTM-D7334-08), and the hydrophobicity of the coating was measured. The lower the contact angle, the more hydrophilic the film. The contact angle is defined as the angle between the film surface and the tangent where the droplet contacts the film. The value of the contact angle of the droplet is determined by the surface energy of the film and the surface tension of the liquid. If complete wetting occurs between the liquid and the film surface, the droplet spreads on the film and the contact angle is approximately equal to 0, whereas if the moisture is only partial, The resulting contact angle is in the range of 0-180 °.

Example 1: Effect of acid catalyst on coating properties:
[0066] Samples 1-7 were prepared by mixing OKS-1081 in a solvent system comprising deionized water and ethanol in a 1: 1 weight ratio to give a solids content of 5 wt% (ie 27 g Of OKS-1081 was added to 60.55 g DI / ethanol). The prescribed acid and silicon alkoxide were then added to the mixture. Each mixture was stirred at room temperature (23 ° C.) for 1 hour. The parts by weight of each component are given in Table 2 below.

  [0067] Each sample is formed into a cured coating by coating a predetermined sample on a polypropylene film to give a cured coating thickness of 2.0 μm and curing each coating at 100 ° C. for 7 minutes. did. Each cured coating was then tested for water resistance and oxygen transmission rate using the water friction test and oxygen transmission rate (OTR) test described above. Samples 1, 5, and 6 are samples of the present invention, and samples 2-4 and 7 are comparative examples. The results are shown in Table 3 below.

Example 2: Effect of PVOH polymer / copolymer on coating properties:
[0068] Samples 8-19 were prepared by mixing a given PVOH in a solvent system containing a 1: 1 weight ratio of deionized water and ethanol to give a solids content of 5 wt% (ie 27 g Of PVOH was added to 60.55 g DI / ethanol). The prescribed acid and silicon alkoxide were then added to the mixture. Each mixture was stirred at room temperature (23 ° C.) for 1 hour. Samples 9 to 16 are samples of the present invention, and samples 8 and 17 to 19 are comparative examples. The parts by weight of each component are given in Table 4 below.

  [0069] Each sample is formed into a cured coating by coating a predetermined sample on a polypropylene film to give a cured coating thickness of 2.0 μm and curing each coating at 100 ° C. for 7 minutes. did. Each cured coating was then tested for water resistance and oxygen transmission rate using the water friction test and oxygen transmission rate (OTR) test described above. The results are shown in Table 5 below.

Example 3: Contact angle and hot water resistance of cured coatings using various acid catalysts:
[0070] Samples 20-26 and a control sample were prepared by mixing OKS-1081 in a solvent system comprising a 1: 1 weight ratio of deionized water and ethanol to give a solids content of 5 wt%. (Ie 27 g of OKS-1081 was added to 60.55 g of DI / ethanol). Next, the prescribed acid and TEOS were added to the mixture of samples 20-26. Each mixture was stirred at room temperature (23 ° C.) for 1 hour. The parts by weight of each component are given in Table 6 below.

  [0071] Each sample is formed into a cured coating by coating a predetermined sample on a polypropylene film to give a cured coating thickness of 2.0 μm and curing each coating at 100 ° C. for 7 minutes. did. Each cured coating was then tested for contact angle and water resistance using the water friction test and boiling water test described above. Samples 20 to 23 are samples of the present invention, and samples 24 to 26 are comparative examples. The results are shown in Table 7 below.

  [0072] As shown in Table 7, Samples 25-26 give a slightly higher contact angle after the sol-gel reaction compared to the control. Accordingly, the water resistance of the cured coatings of Samples 25 to 26 is improved, but the water resistance is inferior.

  [0073] In contrast, Samples 20-23, which use relatively low molecular weight carboxylic acids, give high contact angles, which exhibit stronger hydrophobicity. Furthermore, the cured coatings of Samples 20-23 also give better water resistance, possibly due to less steric hindrance during esterification.

[0074] Although described in detail herein with respect to particular aspects thereof, those skilled in the art will readily conceive modifications, changes, and equivalents to these aspects upon obtaining the above understanding. Will be accepted. Further, as discussed above, the coating compositions of the present invention, the coatings or films produced therefrom, and the methods of making and using the same include the disclosed compositions, the coatings or films produced therefrom, And any one or combination of the elements / steps / features described herein of and how to make and use it can be included, can consist essentially of, or can consist of You should understand what you can do. For example, the coating composition of the present invention, the coating or film produced therefrom, and the method of making and using it can include one or more of the elements described above and consist essentially of it. Or can be constructed from this. Further, the coating compositions of the present invention, the coatings or films produced therefrom, and methods of making and using the same may include other ones that are not specifically discussed herein. It can be included with the elements and can consist essentially of or consist of these. Therefore, the scope of the present invention should be evaluated as that of the claims and their equivalents. All parts and percentages in the examples and the rest of the specification are by weight unless otherwise specified. Further, all numerical ranges set forth in the specification or claims, such as those indicating a particular set of characteristics, units of measure, conditions, physical state, or proportions, are clearly mentioned or otherwise It is intended to literally include all numbers falling within such ranges as indicated by the method, as well as any subset of numbers within any ranges so indicated. For example, whenever a numerical range with a lower limit, R _L and an upper limit, R _U, is disclosed, any number R falling within the range is specifically disclosed. In particular, the next number R in this range: R = R _L + k (R _U −R _L ), where k is a variable in the range of 1% to 100% in 1% increments, for example k is 1%, 2%, 3%, 4%, 5%, ... 50%, 51%, 52%, ... 95%, 96%, 97%, 98%, 99%, or 100% ) Is specifically disclosed. Furthermore, any numerical range represented by any two values of R calculated above is also specifically disclosed. In addition to those shown and described herein, any modification of the present invention will become apparent to those skilled in the art from the foregoing description and accompanying drawings. Such modifications are intended to fall within the scope of the claims. All publications cited herein are hereby incorporated by reference in their entirety.

Claims (54)

  A coating composition comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid.   The coating composition of claim 1 further comprising a solvent comprising water, methanol, ethanol, or a combination thereof.   The method according to claim 1 or 2, further comprising one or more optional additives including colorants, inorganic nanoparticle fillers, crosslinking agents, antioxidants, adhesion promoters, oxygen scavengers, or combinations thereof. Coating compositions.   The coating composition according to any of claims 1 to 3, wherein the polyvinyl alcohol has been solubilized and hydrolyzed and has a degree of polymerization in the range of about 300 to about 5000.   The coating composition of any of claims 1-4, wherein the polyvinyl alcohol is fully hydrolyzed and has a degree of polymerization in the range of about 500 to about 3500.1000.   6. A coating composition according to any preceding claim, wherein the polyvinyl alcohol (PVOH) and the one or more metal alkoxides (MA) are present in a PVOH / MA ratio of about 9/1 to about 5/5.   The coating composition of any of claims 1-6, wherein the polyvinyl alcohol (PVOH) and the one or more metal alkoxides (MA) are present in a PVOH / MA ratio of about 8/2 to about 7/3.   The coating composition according to claim 1, wherein the one or more metal alkoxides comprise one or more silicon alkoxides.   9. The one or more silicon alkoxides according to any of claims 1 to 8, wherein the one or more silicon alkoxides comprise tetraethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, glycidoxypropyltrimethoxysilane, or any combination thereof. Coating composition.   The coating composition according to claim 1, wherein the organic acid comprises a carboxylic acid.   The coating composition according to any of claims 1 to 10, wherein the organic acid comprises a carboxylic acid selected from formic acid, acetic acid, propionic acid, or combinations thereof.   The coating composition according to claim 1, wherein the organic acid comprises acetic acid.   The polyvinyl alcohol is present in an amount ranging from about 5% to about 20% by weight of the coating composition (pbw) and the one or more metal alkoxides are in an amount ranging from about 1% to about 20% pbw of the coating composition. The organic acid is present in an amount ranging from about 1% to about 10% pbw of the coating composition; the solvent is present in an amount of from about 65% to about 90% pbw of the coating composition; The coating composition according to claim 1, wherein the parts are based on the total weight of the coating composition.   Polyvinyl alcohol is present in an amount ranging from about 5% to about 20% pbw of the coating composition, and one or more metal alkoxides are present in an amount ranging from about 1% to about 20% pbw of the coating composition; The organic acid is present in an amount ranging from about 1% to about 10% pbw of the coating composition, the solvent is present in an amount ranging from about 65% to about 90% pbw of the coating composition, and the total weight The coating composition according to claim 1, wherein the parts are based on the total weight of the coating composition.   The reaction product is (i) a first reaction between some hydroxyl groups of the polyvinyl alcohol and one or more metal alkoxides; and (ii) between the remaining hydroxyl groups on the polyvinyl alcohol and the organic acid. The coating composition according to claim 1, which has a molecular structure formed by the second esterification reaction.   The coating composition comprises (i) a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid, and (ii) a colorant, an inorganic nanoparticle filler, a crosslinking agent, an antioxidant, an adhesion promoter, The coating composition according to any one of claims 1 to 15, substantially consisting of one or more optional additives selected from the group consisting of oxygen scavengers or combinations thereof.   The coating composition comprises (i) a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid, and (ii) a colorant, an inorganic nanoparticle filler, a crosslinking agent, an antioxidant, an adhesion promoter, The coating composition according to any one of claims 1 to 15, comprising one or more optional additives selected from the group consisting of oxygen scavengers or combinations thereof.   The coating composition according to any one of claims 1 to 17, which is coated on a substrate.   The coating composition according to any one of claims 1 to 17, which is coated on a substrate, wherein the substrate comprises a film.   A cured coating comprising the coating composition according to claim 1. The cured coating is (i) at least about 20 water resistance as measured using water rub test at room temperature and (ii) 50 cc / m measured at 23 ° C. and less than about 50% relative humidity. 21. A cured coating according to claim 20 having an oxygen transmission rate of less than ² / day. The cured coating is (i) at room temperature water using at least about 50 water measured using a water rub test, and (ii) 25 cc / m measured at 23 ° C. and less than about 50% relative humidity. A cured coating according to claim 20 or 21, having an oxygen transmission rate of less than ² / day. The cured coating is (i) at room temperature water, measured using a water rub test and at least about 50 water resistance, and (ii) 10 cc / m measured at 23 ° C. and less than about 50% relative humidity. 23. A cured coating according to any of claims 20-22 having an oxygen transmission rate of less than ² / day. The cured coating is (i) at room temperature water, measured using a water rub test and at least about 50 water resistance, and (ii) 10 cc / m ² measured at 23 ° C. and about 65% relative humidity. 24. A cured coating according to any one of claims 20 to 23 having an oxygen transmission rate of less than / day. The cured coating is (i) at least about 50 water resistance as measured using water rub test with room temperature water, and (ii) 50 cc / m ² measured at 23 ° C. and about 80% relative humidity. 25. A cured coating according to any of claims 20 to 24 having an oxygen transmission rate of less than 1 day.   26. A cured coating according to any of claims 20-25, wherein the cured coating has a coating thickness of less than 10 microns ([mu] m).   27. A cured coating according to any of claims 20 to 26, wherein the cured coating has a coating thickness of less than about 5 [mu] m.   28. A cured coating according to any of claims 20 to 27, wherein the cured coating has a coating thickness of about 1.0 [mu] m or less.   29. A cured coating according to any of claims 20 to 28, wherein the cured coating has a contact angle of at least 40 [deg.].   30. A cured coating according to any of claims 20 to 29, wherein the coating has a contact angle of at least 45 [deg.].   A coated substrate comprising a substrate and a coating thereon, the coating comprising a cured coating according to any of claims 20-30.   32. A coated substrate according to claim 31, wherein the substrate comprises a film.   32. The coated substrate of claim 31, wherein the substrate further comprises a deoxygenated film.   34. An article comprising one or more food products packaged in one or more food packaging materials, at least a portion of the one or more food packaging materials comprising a cured coating according to any of claims 20-33. . A method for producing a coating composition according to any of claims 1 to 17, comprising:
Forming a mixture comprising polyvinyl alcohol in a solvent;
Adding an organic acid to the mixture; and adding one or more metal alkoxides to the mixture;
Including:
(1) catalyze the reaction between (i) hydroxyl groups on polyvinyl alcohol and (ii) one or more metal alkoxides; and (2) (i) the remaining hydroxyl groups on polyvinyl alcohol and (ii) Said process wherein an amount of organic acid is added to the mixture which allows an esterification reaction with the organic acid. Applying the coating composition onto the substrate;
36. The method of claim 35, further comprising:   40. The method of claim 36, wherein the substrate comprises a film.   38. A method according to any of claims 35 to 37, further comprising curing the coating composition to remove the solvent.   38. A method according to any of claims 35 to 37, wherein the solvent comprises water, alcohol, glycol, or a combination thereof.   40. The method of claim 38, wherein the curing step comprises heating the mixture to a temperature of at least 100 <0> C for a time of at least about 5 minutes. Including the reaction product of polyvinyl alcohol and one or more metal alkoxides;
(I) at least about 20 water resistance as measured using water friction test using room temperature water, and (ii) less than 50 cc / m ² / day measured at 23 ° C. and less than about 50% relative humidity. A coating having an oxygen transmission rate of The coating is (i) water at room temperature, measured using a water rub test to have a water resistance of at least about 50, and (ii) 25 cc / m ² measured at 23 ° C. and less than about 50% relative humidity. 42. The coating of claim 41, having an oxygen transmission rate of less than / day. The coating is (i) water-resistant at room temperature, measured using a water rub test, at least about 50, and (ii) 10 cc / m ² measured at 23 ° C. and less than about 50% relative humidity. 42. The coating of claim 41, having an oxygen transmission rate of less than / day. The coating is (i) water-resistant at room temperature, measured using a water rub test, at least about 50, and (ii) 10 cc / m ² / measured at 23 ° C. and about 65% relative humidity. 42. The coating of claim 41 having an oxygen transmission rate of less than a day. The coating is (i) water-resistant at room temperature, measured using a water friction test, at least about 50, and (ii) 50 cc / m ² / measured at 23 ° C. and about 80% relative humidity. 42. The coating of claim 41 having an oxygen transmission rate of less than a day.   42. The coating of claim 41, wherein the coating has a coating thickness of less than 10 microns ([mu] m).   42. The coating of claim 41, wherein the coating has a coating thickness of less than about 5 [mu] m.   42. The coating of claim 41, wherein the coating has a coating thickness of about 1.0 [mu] m or less. Comprising a reaction product of polyvinyl alcohol, one or more metal alkoxides, and an organic acid;
A coating having a contact angle of at least 35 °.   50. The coating of claim 49, wherein the coating has a contact angle of at least 40 degrees.   50. The coating of claim 49, wherein the coating has a contact angle of at least 45 degrees. Comprising a reaction product of polyvinyl alcohol and one or more metal alkoxides;
Gas and moisture barrier coatings having a contact angle of at least 35 °.   53. The coating of claim 52, wherein the coating has a contact angle of at least 40 degrees.   53. The coating of claim 52, wherein the coating has a contact angle of at least 45 degrees.

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