A composition

Abstract

A composition for a closure for packaging, the composition comprising: (a) a polyol material; and (b) a non-blocked isocyanate material; wherein the composition is substantially free of covalent halogen-containing resin materials and precursors thereof. The invention extends to methods producing a closure for packaging, closures for packaging and packaging comprising said closures.

Description

A CompositionField

[0001] The present invention relates to a composition for a closure for packaging, such as food and / or beverage packaging. The composition comprises a polyol material and a non-blocked isocyanate material and is substantially free of covalent halogen-containing resin materials and precursors thereof. The invention extends to methods for producing a closure for packaging, such as food and / or beverage packaging. The invention also extends to closures and packaging, such as food and / or beverage packaging, having a sealing compound on at least a portion thereof, the sealing compound being derived from a composition according to the invention.Background

[0002] Food and / or beverage packaging is typically hermetically sealed to protect the contents from spoiling. The contents should be protected from spoiling even during processes of manufacture where extreme conditions are often applied, such as, for example, during heat sterilization and / or pasteurization of foodstuffs. In order to ensure the insulation of the contents from the environment, suitable sealing compounds are typically applied to the lids, or closures, of the food and / or beverage packaging.

[0003] Sealing compounds for food and / or beverage packaging should have sufficient stability towards the packaged contents both during sterilization and / or pasteurization processes and also during subsequent storage, which can often extend over a period of several months or even years. The sealing compounds should also have good adhesion to the closure and have good chemical resistance to the packaged contents, which in some cases may be chemically aggressive. Further, there should be a minimal amount of alteration to the packaged contents from materials that are products of erosion of the container, or from the sealing compound itself. Accordingly, the sealing compound, as well as any other coatings used to coat the internal surfaces of the package, should be designed such that it is able to withstand contact with these aggressive chemicals and to minimise the release of material from the sealing compound into the contents of the container.

[0004] Typically sealing compounds used for closures of food and / or beverage packaging contain polyvinyl chloride (PVC) plastisols, i.e., a colloidal dispersion of PVC particles in a liquid plasticizer. It is known that plasticizer migration from the sealing composition occurs under the influence of certain foodstuffs, in particular fatty and oily substances, and thermal stress (such as pasteurization, sterilization, etc.). The degree of plasticizer migration can, in some cases, exceed levels that are allowable under regulations in foodstuffs legislation. Additionally, under certain pasteurized and sterilized conditions, plasticizer migration may cause a loss of vacuum resulting in packaging that is not hermetically sealed.Furthermore, PVC plastisol-based sealing compounds can start to dissolve and / or swell during thermal stress (such as pasteurization, sterilization, etc.), particularly when the packaged contents include solvent-containing materials.

[0005] The disposal of PVC-containing waste is becoming increasingly problematical and costintensive.

[0006] It is an object of aspects of the present invention to provide a solution to one or more of the above-mentioned problems.Summary

[0007] According to the present invention there is provided a composition for a closure for packaging, the composition comprising:(a) a polyol material; and(b) a non-blocked isocyanate material; wherein the composition is substantially free of covalent halogen-containing resin materials and precursors thereof.

[0008] The composition may be applied to a closure for packaging. The composition may be applied to a closure for packaging at an application temperature, T. The composition may be a liquid at the application temperature, T.

[0009] There is also provided a method for producing a closure for packaging, the method comprising the steps of:(i) providing a closure for packaging, the closure having an interior and an exterior surface;(ii) applying a composition to at least a portion of the interior surface of the closure at an application temperature, T, the composition comprising:(a) a polyol material; and(b) a non-blocked isocyanate material; wherein the coating composition is substantially free of covalent halogencontaining resin materials and precursors thereof; and wherein the composition is liquid at the application temperature, T; and(iii) at least partially curing the composition to form a sealing compound.

[0010] There is also provided a closure for packaging produced by a method comprising the steps of:(i) providing a closure for packaging, the closure having an interior and an exterior surface;(ii) applying a composition to at least a portion of the interior surface of the closure at an application temperature, T, the composition comprising:(a) a polyol material; and(b) a non-blocked isocyanate material;wherein the composition is substantially free of covalent halogen-containing resin materials and precursors thereof; and wherein the composition is liquid at the application temperature, T; and(Hi) at least partially curing the composition to form a sealing compound.

[0011] There is also provided a closure for packaging, the closure having disposed on at least a portion thereof a sealing compound, the sealing compound being derived from a composition comprising:(a) a polyol material; and(b) a non-blocked isocyanate material; wherein the composition is substantially free of covalent halogen-containing resin materials and precursors thereof.

[0012] There is also provided packaging comprising a closure, the closure having disposed on at least a portion thereof a sealing compound, the sealing compound being derived from a composition comprising:(a) a polyol material; and(b) a non-blocked isocyanate material; wherein the composition is substantially free of covalent halogen-containing resin materials and precursors thereof.Detailed Description

[0013] The present invention relates to a composition. The composition comprises a polyol material. By “polyol”, and like terms as used herein, is meant a material having at least two hydroxyl groups. The polyol material may comprise any suitable polyol material.

[0014] The polyol material may comprise a hydroxyl-functional polymer. For example, the polyol material may comprise a polyester, a polyolefin, a polyacrylate, a polyether, an alkyd resin, a polycarbonate, a polycaprolactone, a polyurethane, a polysiloxane, copolymers thereof and / or combinations thereof, wherein each of the aforementioned polymers comprise at least two hydroxyl groups.

[0015] The polyol material may comprise a polyester, a polyether, a polycarbonate and / or combinations thereof.

[0016] The polyol material may comprise a polyester polyol. The polyester polyol may suitably be of the following formula: HO-[-R'-O-C(=O)-R”-C(=O)-]n-O-R'”-OH, wherein each R group is independently an alkylene group, an alkenylene group, an alkynylene group or an arylene group, and n is at least 1 . The hydroxyl groups of the polyester polyol may be present at one or more terminal ends of polymer backbone and / or may be present as side group(s).

[0017] The polyol material may comprise a commercially available polyester polyol. Suitable commercially available polyester polyols include, but are not limited to, those sold under the tradename Tego (RTM) commercially available from Evonik, such as Tego Addbond LP 1600,LP1611 , LTW, LTW-B, LTH, 2440 and 2325; those sold under the trade name URALAC (RTM) commercially available from DSM, such as URALAC P1580; and combinations thereof.

[0018] The polyol material may comprise a polyether polyol. The polyether polyol may suitably be of the following formula: HO-R'-[O-R"-O-]n-R"’-OH, wherein each R group is independently an alkylene group, an alkenylene group, an alkynylene group or an arylene group, and n is at least 1. Each R group may independently be an alkylene group, such as a C1 -C10 alkylene group, such as a C1 -C6 alkylene group, such as a C1 -C4 alkylene group, such as a C2-C4 alkylene group, such as ethylene or propylene. Each R group may be propylene. The hydroxyl groups of the polyether polyol may be present at one or more terminal ends of polymer backbone and / or may be present as side group(s).

[0019] The polyol ethers may include alkoxylated polyol ethers.

[0020] Examples of suitable polyether polyols include, but are not limited to, polybutylene glycol, polypropylene glycol, polyethylene glycol, poly(tetramethylene) glycol (PTMEG; otherwise known as polytetrahydrofuran) and / or combinations thereof.

[0021] The polyol material may comprise one or more polyether polyol(s). For example, the polyol material may comprise a single polyether polyol or may comprise a combination of two or more polyether polyols.

[0022] The polyol material may comprise one or more polypropylene glycol(s). For example, the polyol material may comprise a single polypropylene glycol or may comprise a combination of two or more polypropylene glycols.

[0023] The polyol material may comprise poly(tetramethylene) glycol.

[0024] The polyol material may comprise a commercially available polyether polyol. Examples of suitable commercially available polyether polyols include those sold under the trade name DESMOPHEN (RTM) commercially available from Covestro, such as DESMOPHEN 1380 and DESMOPHEN 1110, those sold under the trade name Acclaim (RTM) commercially available from Covestro, such as Acclaim Polyol 4200; those sold under the trade name TERATHANE (RTM) commercially available from Invista, such as TERATHANE 650, 1000, 1800 and 2000; those sold under the tradename PolyTHF (RTM) commercially available from BASF, such as PolyTHF 250, 650, 1000, 1400, 1800 and 2000; and / or combinations thereof.

[0025] The polyol material may comprise a polycarbonate polyol. The polycarbonate polyol may suitably be of the following formula: HO-[-R’-O-C(=O)-O-]n-R”'-OH, wherein each R group is independently an alkylene group, an alkenylene group, an alkynylene group or an arylene group, and n is at least 1. The hydroxyl groups of the polycarbonate polyol may be present at one or more terminal ends of polymer backbone and / or may be present as side group(s).

[0026] The polyol material may comprise a commercially available polycarbonate polyol. Examples of suitable commercially available polycarbonate polyols include those sold under the trade name ETERNACOLL (RTM) commercially available from UBE Corporation, such as ETERNACOLL UH200, PH200D, UH100, PH100, PH300D, PH50, UD100, UH300, UH50, UM90(1 / 1 ), UM90(1 / 3) and UM90(3 / 1 ); those sold under the trade name DESMOPHEN (RTM)commercially available from Covestro, such as DESMOPHEN C1200, C2100, C2102 and C2202; and combinations thereof.

[0027] The polyol material may comprise a polycarbonate-polyester polyol. The polyol material may comprise a commercially available polycarbonate-polyester polyol. Examples of suitable commercially available polycarbonate-polyester polyols include those sold under the trade name ETERNACOLL (RTM) commercially available from UBE Corporation, such as ETERNACOLL UH50-100 and UHC50-200; and combinations thereof.

[0028] The polyol material may comprise a polycarbonate-polyether polyol. The polyol material may comprise a commercially available polycarbonate-polyether polyol. Examples of suitably commercially available polycarbonate-polyether polyols include those sold under the trade name ETERNACOLL (RTM) commercially available from UBE Corporation, such as ETERNACOLL UT-200; and combinations thereof.

[0029] The polyol material may have any suitable hydroxyl value (OHV; also known as hydroxyl number or OHN, which terms may be used interchangeably herein). The polyol material may have a hydroxyl value of at least 10 mg KOH / g, such as at least 15 mg KOH / g, such as at least 20 mg KOH / g, such as at least 25 mg KOH / g, such as at least 30 mg KOH / g, such as at least 35 mg KOH / g, such as at least 40 mg KOH / g, such as at least 45 mg KOH / g, such as at least 50 mg KOH / g.

[0030] The polyol material may have a hydroxyl value of at least 25 mg KOH / g.

[0031] The polyol material may have a hydroxyl value of at least 50 mg KOH / g.

[0032] The polyol material may have a hydroxyl value of at least 100 mg KOH / g.

[0033] The polyol material may have a hydroxyl value of at least 200 mg KOH / g.

[0034] The polyol material may have a hydroxyl value of at least 300 mg KOH / g.

[0035] The hydroxyl values (OHV) reported herein are suitably expressed on solids.

[0036] As reported herein, the hydroxyl value is the number of mg of KOH equivalent to the hydroxyl groups in 1g of material. In such as method, a sample (typically, 0.1 to 3g) was weighed accurately into a conical flask and is dissolved, using light heating and stirring as appropriate, in 20ml of tetrahydrofuran. 10ml of 0.1M 4-(dimethylamino)pyridine in tetrahydrofuran (catalyst solution) and 5ml of a 9 vol% solution of acetic anhydride in tetrahydrofuran (i.e. 90ml acetic anhydride in 910ml tetrahydrofuran; acetylating solution) were then added to the mixture. After 5 minutes, 10ml of an 80 vol% solution of tetrahydrofuran (i.e. 4 volume parts tetrahydrofuran to 1 part distilled water; hydrolysis solution) was added. After 15 minutes, 10ml tetrahydrofuran was added and the solution is titrated with 0.5M ethanolic potassium hydroxide (KOH). A blank sample was also run where the sample of solid polyurethane imide is omitted. The resulting hydroxyl number is expressed in units of mg KOH / g and is calculated using the following equation:Hydroxyl value = ((V2 - Vi) x molarity of KOH solution (M) x 56.1) / weight of solid sample (g)wherein Vi is the titre of KOH solution (ml) of the polyurethane imide sample and V2 is the titre of KOH solution (ml) of the blank sample.

[0037] All values for hydroxyl value reported herein were measured in this way unless specified otherwise.

[0038] The polyol material may have any suitable acid value (AV; also known as acid number or AN, which terms may be used interchangeably herein). The polyol material may have an acid value up to 10 mg KOH / g, such as up to 5 mg KOH / g, such as up to 2 mg KOH / g, such a up to 1 mg KOH / g, such as up to 0.5 mg KOH / g. The polyol material may have an acid value from 0 to 10 mg KOH / g, such as from 0 to 5 mg KOH / g, such as from 0 to 2 mg KOH / g, such as from 0 to 1 mg KOH / g, such as from 0 to 0.5 mg KOH / g. The polyol material may have an acid value of 0 mg KOH / g.

[0039] The polyol material may have an acid value up to 1 mg KOH / g.

[0040] The polyol material may have an acid value up to 0.5 mg KOH / g.

[0041] The acid values reported herein are suitably expressed on solids.

[0042] As reported herein, the acid value was determined by titration with 0.1 N methanolic potassium hydroxide solution. The sample of polymer (0.1 - 3 grams depending on acid value) was weighed accurately (on a balance with accuracy to weigh in milligrams) into a conical flask and was then dissolved in 25 millilitres of a solvent mixture containing dichloromethane and ethanol (3 / 1 w / w) and a few drops of 0.1% solution bromo thymol blue indicator; using light heating and stirring as appropriate. The solution was then cooled to room temperature (20 - 30 °C) and the solution titrated with the potassium hydroxide solution. The resulting acid value (acid number) is expressed in units of mg KOH / g and is calculated using the following equation.Acid Value = (titre KOH solution (mis) x molarity KOH solution x 56.1 ) I Weight of solid sample (grams)

[0043] All values for acid value reported herein were measured in this way unless specified otherwise.

[0044] The polyol material may be a liquid, solution, dispersion or a solid (i.e., powder) at room temperature. The polyol material may be a liquid at room temperature. The term “liquid” when used in relation to the polyol material refers to a polyol material which is a fluid that is able to flow freely and has a near constant volume at room temperature.

[0045] The polyol material may have a viscosity from 10 to 50,000 mPa.s, such as from 20 to 25,000 mPa.s, such as from 30 to 20,000 mPa.s, such as from 40 to 15,000 mPa.s, such as from 50 to 10,000 mPa.s, such as from 60 to 9,000 mPa.s at 75°C. As reported herein, the viscosity of the polyol material may be determined in accordance with DIN 53019 / 1 at a shear rate of 10 s1.

[0046] When the polyol material is a liquid, the polyol material may have any suitable bulk density at 25°C. For example, the polyol material may have a bulk density at 25°C from 1 to 2g / cm3, such as from 1 to 1.7 g / cm3, such as from 1 to 1.5 g / cm3, such as from 1 to 1.2 g / cm3, or even 1 g / cm3.

[0047] The composition may comprise any suitable amount of polyol material. The composition may comprise up to 90 wt%, such as up to 85 wt%, such as up to 80 wt%, such as up to 75 wt%, such as up to 70 wt%, such as up to 65 wt%, such as up to 60 wt%, such as up to 55 wt% polyol material based on the total weight of the composition. The composition may comprise at least 5 wt%, such as at least 10 wt%, such as at least 15 wt%, such as at least 20 wt%, such as at least 25 wt%, such as at least 30 wt%, such as at least 35 wt%, such as at least 40 wt% polyol material based on the total weight of the composition.

[0048] The composition may comprise from 5 to 90 wt%, such as from 5 to 85 wt%, such as from 5 to 80 wt%, such as from 5 to 75 wt%, such as from 5 to 70 wt%, such as from 5 to 65 wt%, such as from 5 to 60 wt%, such as from 5 to 55 wt% polyol material based on the total weight of the composition. The composition may comprise from 10 to 90 wt%, such as from 10 to 85 wt%, such as from 10 to 80 wt%, such as from 10 to 75 wt%, such as from 10 to 70 wt%, such as from 10 to 65 wt%, such as from 10 to 60 wt%, such as from 10 to 55 wt% polyol material based on the total weight of the composition. The composition may comprise from 15 to 90 wt%, such as from 15 to 85 wt%, such as from 15 to 80 wt%, such as from 15 to 75 wt%, such as from 15 to 70 wt%, such as from 15 to 65 wt%, such as from 15 to 60 wt%, such as from 15 to 55 wt% polyol material based on the total weight of the composition. The composition may comprise from 20 to 90 wt%, such as from 20 to 85 wt%, such as from 20 to 80 wt%, such as from 20 to 75 wt%, such as from 20 to 70 wt%, such as from 20 to 65 wt%, such as from 20 to 60 wt%, such as from 20 to 55 wt% polyol material based on the total weight of the composition. The composition may comprise from 25 to 90 wt%, such as from 25 to 85 wt%, such as from 25 to 80 wt%, such as from 25 to 75 wt%, such as from 25 to 70 wt%, such as from 25 to 65 wt%, such as from 25 to 60 wt%, such as from 25 to 55 wt% polyol material based on the total weight of the composition. The composition may comprise from 30 to 90 wt%, such as from 30 to 85 wt%, such as from 30 to 80 wt%, such as from 30 to 75 wt%, such as from 30 to 70 wt%, such as from 30 to 65 wt%, such as from 30 to 60 wt%, such as from 30 to 55 wt% polyol material based on the total weight of the composition. The composition may comprise from 35 to 90 wt%, such as from 35 to 85 wt%, such as from 35 to 80 wt%, such as from 35 to 75 wt%, such as from 35 to 70 wt%, such as from 35 to 65 wt%, such as from 35 to 60 wt%, such as from 35 to 55 wt% polyol material based on the total weight of the composition. The composition may comprise from 40 to 90 wt%, such as from 40 to 85 wt%, such as from 40 to 80 wt%, such as from 40 to 75 wt%, such as from 40 to 70 wt%, such as from 40 to 65 wt%, such as from 40 to 60 wt%, such as from 40 to 55 wt% polyol material based on the total weight of the composition.

[0049] The composition may comprise from 40 to 60 wt% polyol material based on the total weight of the composition.

[0050] The composition comprises a non-blocked isocyanate material. Suitable non-blocked isocyanate materials are those having on average at least two isocyanate (NCO) groups permolecule. The non-blocked isocyanate materials may be monomers, oligomers or prepolymers having at least two isocyanate groups per molecule. The prepolymers may have been prepared, for example, by the reaction of a diisocyanate with a chain extender.

[0051] By “non-blocked”, and like terms as used herein, in relation to the isocyanate material is meant that at least 50%, such as at least 55 wt%, such as at least 60 wt%, such as at least 65 wt%, such as at least 70 wt%, such as at least 75 wt%, such as at least 80 wt%, such as at least 85 wt%, such as at least 90 wt%, such as at least 95 wt%, such as at least 99 wt%, such as at least 99.9 wt%, or even 100 wt% of the isocyanate groups of the material are free isocyanate groups, i.e., are not chemically blocked, for example, by one or more isocyanate blocking agents. For example, at least 95 wt%, such as at least 99 wt%, such as at least 99.9 wt% of the isocyanate groups of the material are free isocyanate groups, i.e., are not chemically blocked, for example, by one or more isocyanate blocking agents. Isocyanate blocking agents will be known to a person skilled in the art. Examples of blocking agents include amino acids; cyclized amino acids; sugars; malonic acid; malonic esters; oximes, such as acetoxime, methylethyl ketoxime, diethyl ketoxime, acetophenone oxime, cyclohexanone oxime, cyclopentanone oxime, formaldoxime and acetaldoxime; phenols; and caprolactams.

[0052] The composition may be substantially free, may be essentially free or may be completely free of isocyanate blocking agents. By “substantially free” we mean to refer to compositions containing less than 0.5 wt% of isocyanate blocking agents. By “essentially free” we mean to refer to compositions containing less than 0.1 wt% of isocyanate blocking agents. By “completely free” we mean to refer to compositions containing less than 0.01 wt% of isocyanate blocking agents.

[0053] The non-blocked isocyanate material may comprise any suitable non-blocked isocyanate material. Examples of suitable non-blocked isocyanate materials include, but are not limited to, those based on hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, methylene-4,4'-bis(cyclohexyl isocyanate), bis-(4-isocyanatocyclohexyl)methane, methylene diphenyl diisocyanate, bis-(4-isocyanatophenyl)methane, tetramethyl-meta-xylylene diisocyanate, meta xylylene diisocyanate, para xylylene diisocyanate, cyclohexane diisocyanate, naphthalene diisocyanate, trimethyl hexamethylene diisocyanate and / or combinations thereof. For example, the non-blocked isocyanate material may comprise a based on hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, methylene-4,4’-bis(cyclohexyl isocyanate), bis-(4-isocyanatocyclohexyl)methane, methylene diphenyl diisocyanate, bis-(4-isocyanatophenyl)methane, tetramethyl-meta-xylylene diisocyanate, meta xylylene diisocyanate, para xylylene diisocyanate, cyclohexane diisocyanate, naphthalene diisocyanate, trimethyl hexamethylene diisocyanate and / or combinations thereof.

[0054] The non-blocked isocyanate material may comprise a biuret. A person skilled in the art will know that a biuret is a compound of the formula R1R2N-C(=O)-N(R3)-C(=O)-NR4R5, wherein each R group is independently an alkylene group, an alkenylene group, an alkynylene group oran arylene group. The non-blocked isocyanate material may comprise an isocyanurate. When the non-blocked isocyanurate material comprises an isocyanurate, the substantial absence of isocyanate blocking agents in the isocyanurate and / or the composition may be indicative that isocyanurate is derived from a non-blocked isocyanate.

[0055] The non-blocked isocyanate material may comprise a polyisocyanate based on hexamethylene-1 ,6-diisocyanate (H D I).

[0056] The non-blocked isocyanate material may comprise a commercially available nonblocked isocyanate material. Examples of suitable commercially available non-blocked isocyanate material include, but are not limited to, those sold under the trade name DESMODUR (RTM) commercially available from Covestro, such as DESMODUR N3600; those sold under the trade name Tolonate (RTM) commercially available from Vencorex, such as Tolonate HDB-LV; and / or combinations thereof.

[0057] The non-blocked isocyanate material may have any suitable isocyanate (NCO) content. The non-blocked isocyanate material may have an isocyanate (NCO) content of at least 5 wt%, such as at least 10 wt%, such as at least 15 wt%, or even at least 20 wt%.

[0058] The non-blocked isocyanate material may be a liquid, solution, dispersion or a solid (i.e., powder) at room temperature. The non-blocked isocyanate material may be a liquid at room temperature. The term “liquid” when used in relation to the non-blocked isocyanate material refers to a non-blocked isocyanate material which is a fluid that is able to flow freely and has a near constant volume at room temperature.

[0059] The non-blocked isocyanate material may have a viscosity from 10 to 50,000 mPa.s, such as from 20 to 25,000 mPa.s, such as from 30 to 20,000 mPa.s, such as from 40 to 15,000 mPa.s, such as from 50 to 10,000 mPa.s, such as from 60 to 9,000 mPa.s at 75°C. As reported herein, the viscosity of the non-blocked isocyanate material may be determined in accordance with DIN 53019 / 1 at a shear rate of 10 s‘1.

[0060] When the non-blocked isocyanate material is a liquid, the non-blocked isocyanate material may have any suitable bulk density at 25°C. For example, the non-blocked isocyanate material may have a bulk density at 25°C from 1 to 2 g / cm3, such as from 1 to 1 .7 g / cm3, such as from 1 to 1.5 g / cm3, such as from 1 to 1 .2 g / cm3, or even 1 g / cm3.

[0061] The composition may comprise any suitable amount of non-blocked isocyanate material. The composition may comprise any suitable amount of non-blocked isocyanate material. The composition may comprise up to 90 wt%, such as up to 85 wt%, such as up to 80 wt%, such as up to 75 wt%, such as up to 70 wt%, such as up to 65 wt%, such as up to 60 wt%, such as up to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise at least 5 wt%, such as at least 10 wt%, such as at least 15 wt%, such as at least 20 wt%, such as at least 25 wt%, such as at least 30 wt%, such as at least 35 wt%, such as at least 40 wt% non-blocked isocyanate material based on the total weight of the composition.

[0062] The composition may comprise from 5 to 90 wt%, such as from 5 to 85 wt%, such as from 5 to 80 wt%, such as from 5 to 75 wt%, such as from 5 to 70 wt%, such as from 5 to 65 wt%, such as from 5 to 60 wt%, such as from 5 to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise from 10 to 90 wt%, such as from 10 to 85 wt%, such as from 10 to 80 wt%, such as from 10 to 75 wt%, such as from 10 to 70 wt%, such as from 10 to 65 wt%, such as from 10 to 60 wt%, such as from 10 to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise from 15 to 90 wt%, such as from 15 to 85 wt%, such as from 15 to 80 wt%, such as from 15 to 75 wt%, such as from 15 to 70 wt%, such as from 15 to 65 wt%, such as from 15 to 60 wt%, such as from 15 to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise from 20 to 90 wt%, such as from 20 to 85 wt%, such as from 20 to 80 wt%, such as from 20 to 75 wt%, such as from 20 to 70 wt%, such as from 20 to 65 wt%, such as from 20 to 60 wt%, such as from 20 to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise from 25 to 90 wt%, such as from 25 to 85 wt%, such as from 25 to 80 wt%, such as from 25 to 75 wt%, such as from 25 to 70 wt%, such as from 25 to 65 wt%, such as from 25 to 60 wt%, such as from 25 to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise from 30 to 90 wt%, such as from 30 to 85 wt%, such as from 30 to 80 wt%, such as from 30 to 75 wt%, such as from 30 to 70 wt%, such as from 30 to 65 wt%, such as from 30 to 60 wt%, such as from 30 to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise from 35 to 90 wt%, such as from 35 to 85 wt%, such as from 35 to 80 wt%, such as from 35 to 75 wt%, such as from 35 to 70 wt%, such as from 35 to 65 wt%, such as from 35 to 60 wt%, such as from 35 to 55 wt% non-blocked isocyanate material based on the total weight of the composition. The composition may comprise from 40 to 90 wt%, such as from 40 to 85 wt%, such as from 40 to 80 wt%, such as from 40 to 75 wt%, such as from 40 to 70 wt%, such as from 40 to 65 wt%, such as from 40 to 60 wt%, such as from 40 to 55 wt% non-blocked isocyanate material based on the total weight of the composition.

[0063] The composition may comprise from 40 to 60 wt% non-blocked isocyanate material based on the total weight of the composition.

[0064] The composition may comprise from 50 to 60 wt% non-blocked isocyanate material based on the total weight of the composition.

[0065] The composition may comprise any suitable molar ratio of hydroxyl groups to isocyanate groups (OH:NCO). The molar ratio of hydroxyl groups to isocyanate groups (OH:NCO) may be from10:1 to 1 :10, such as from 10:1 to 1 :5, such as from 10:1 to 1 :2, such as from 10:1 to 1 :1, such as from 5:1 to 1 :1, such as from 2:1 to 1 :1, such as from 1 .5:1 to 1 :1 , or even 1 :1 .

[0066] The molar ratio of hydroxyl groups to isocyanate groups (OH:NCO) may be 1 :1 .

[0067] The molar ratio of hydroxyl groups to isocyanate groups (OH:NCO) may be greater than 1, i.e., the hydroxyl groups may be in excess of the isocyanate groups. When the compositioncomprises an excess of hydroxyl groups compared to isocyanate groups, this may be achieved by any suitable means. For example, suitable amounts of polyol material and non-blocked isocyanate material may be included in the composition such that the molar ratio of hydroxyl groups to isocyanate groups (OH:NCO) is greater than 1.

[0068] At least a portion of the non-blocked isocyanate material, such as at least 10, 20, 30, 40, 50, 60, 70, 80, 90 or 100 wt% of the non-blocked isocyanate material may be pre-reacted with the polyol material. By “pre-reacted”, and like terms as used herein, is meant that at least a portion of the non-blocked isocyanate material is reacted with the polyol material at any suitable time, T, before cure (wherein “cure” is as described herein). For example, at least a portion of the non-blocked isocyanate material may be reacted with the polyol material before the polyol material and non-blocked isocyanate material are added to the composition. It will be appreciated by the skilled person that the reaction of a hydroxyl group and isocyanate group produces a urethane group / linkage. As such, when at least a portion of the non-blocked isocyanate material is pre-reacted with the polyol material, the composition may comprise a polyurethane (i.e., a material having two or more urethane groups). For the avoidance of doubt, when at least a portion of the non-blocked isocyanate material is pre-reacted with the polyol material, the reaction product, i.e., polyurethane, present in the composition must be derived from a polyol and a non-blocked isocyanate material. The substantial absence of isocyanate blocking agents in the composition may be indicative that the reaction product, i.e., polyurethane, is derived from a non-blocked isocyanate material.

[0069] As described herein, the molar ratio of hydroxyl groups to isocyanate groups (OH:NCO) may be greater than 1 , i.e., the hydroxyl groups may be in excess of the isocyanate groups. When the hydroxyl groups are in excess of the isocyanate groups, it will be appreciated that the reaction product of the non-blocked isocyanate material and the polyol material, i.e., polyurethane, will suitably remain hydroxyl-functional even when 100 wt% of the isocyanate material is pre-reacted with the polyol material.

[0070] As will be described hereinbelow, the composition may be provided as a multi-part composition, such as a two-part composition. For example, the composition may comprise at least a first part and a second part, wherein at least one of the first part and / or second part is at room temperature. When the composition comprises at least a first part and a second part, the polyol material and at least a portion of the non-blocked isocyanate material may be provided in separate parts of the composition. For example, the polyol material may be present in one part of the composition and at least a portion of the non-blocked isocyanate material may be present in the other part of the composition. When the polyol material and non-blocked isocyanate material are provided in separate parts of the composition, at least a portion of the non-blocked isocyanate material, such as at least 10, 20, 30, 40, 50, 60, 70, 80, 90 wt% of the non-blocked isocyanate material, may be “pre-reacted” with the polyol material (wherein “pre-reacted” is as defined hereinabove). When at least a portion of the non-blocked isocyanate material is prereacted with the polyol material and the composition comprises at least a first part and a secondpart, the reaction product of the non-blocked isocyanate material and the polyol material, i.e., polyurethane, may suitably be present in in one part of the composition and the remainder of the non-blocked isocyanate material may suitably be present in the other part of the composition. For example, the reaction product of the non-blocked isocyanate material and the polyol material, i.e., polyurethane, may be provided in a first part of the composition. The remainder of the non-blocked isocyanate material may then be provided in a second part of the composition. In such scenarios, the polyol material is typically in excess of the remaining isocyanate material.

[0071] The composition may further comprise a catalyst. Suitable catalysts will be well known to the person skilled in the art. The catalyst may be a non-metal, a metal catalyst or a combination thereof. Suitable non-metal catalysts include, but are not limited to, amine catalysts such as 1,4- Diazabicyclo[2.2.2]octane, DABCO™ (commercially available from Sigma Aldrich); phosphoric acid; blocked phosphoric acid; phosphatised resins such as, for example, phosphatised epoxy resins and phosphatised acrylic resins; CYCAT (RTM) XK 406 N (commercially available from Allnex); sulfuric acid; sulfonic acid; CYCAT 600 (commercially available from Allnex); NACURE (RTM) 5076 or NACURE 5925 (commercially available from King industries); acid phosphate catalyst such as NACURE XC 235 (commercially available from King Industries); and combinations thereof.

[0072] Suitable metal catalysts will be well known to the person skilled in the art. Suitable metal catalysts include, but are not limited to the following: tin containing catalysts, such as monobutyl tin tris (2-ethylhexanoate), dibutyltin dilaurate, (DBTDL); zirconium containing catalysts, such as K-KAT (RTM) 4205, K-KAT 6212 (commercially available from King Industries); titanate based catalysts, such as t-butyl titanate, for example Tyzor TnBT (commercially available from Dorf Ketal); bismuth containing catalysts, such as K-KAT XC-B221 , K-KAT 348, K-KAT XK 651 , K- KAT XK 640 and K-KAT XK 651 (commercially available from King Industries); zinc containing catalysts such as K-KAT XK 672 (commercially available from King Industries); and combinations thereof.

[0073] The catalyst may comprise a metal catalyst.

[0074] The catalyst may comprise a titanate-based catalyst, such as t-butyl titanate.

[0075] The composition may comprise any suitable amount of catalyst. The composition may comprise at least 0.001 wt%, such as at least 0.002 wt%, such as at least 0.003 wt%, such as at least 0.004 wt%, such as at least 0.005 wt% catalyst based on the total weight of the composition. The composition may comprise up to 0.1 wt%, such as up to 0.05 wt%, such as up to 0.025 wt%, such as up to 0.01 wt% catalyst based on the total weight of the composition.

[0076] The composition may comprise from 0.001 to 0.1 wt%, such as from 0.001 to 0.05 wt%, such as from 0.001 to 0.025 wt%, such as from 0.001 to 0.01 wt% catalyst based on the total weight of the composition. The composition may comprise from 0.002 to 0.1 wt%, such as from 0.002 to 0.05 wt%, such as from 0.002 to 0.025 wt%, such as from 0.002 to 0.01 wt% catalyst based on the total weight of the composition. The composition may comprise from 0.003 to 0.1 wt%, such as from 0.003 to 0.05 wt%, such as from 0.003 to 0.025 wt%, such as from 0.003 to0.01 wt% catalyst based on the total weight of the composition. The composition may comprise from 0.004 to 0.1 wt%, such as from 0.004 to 0.05 wt%, such as from 0.004 to 0.025 wt%, such as from 0.004 to 0.01 wt% catalyst based on the total weight of the composition. The composition may comprise from 0.005 to 0.1 wt%, such as from 0.005 to 0.05 wt%, such as from 0.005 to 0.025 wt%, such as from 0.005 to 0.01 wt% catalyst based on the total weight of the composition.

[0077] The composition may comprise from 0.005 to 0.01 wt% catalyst based on the total weight of the composition.

[0078] The composition may comprise a colorant. As used herein, the term "colorant" means any substance that imparts colour and / or other opacity and / or other visual effect to the composition. The colorant can be added to the composition in any suitable form, such as discrete particles, dispersions, solutions and / or flakes. A single colorant or a mixture of two or more colorants can be used in the compositions of the present invention. Suitable colorants will be well known to a person skilled in the art. Suitable colorants are listed in U.S. Patent No. 8,614,286, column 7, line 2 through column 8, line 65, which is incorporated by reference herein.

[0079] The colorant may be approved for food contact. For example, the colorant may comprise those listed in Article 178.3297 of the Code of Federal Regulations, which is incorporated by reference herein.

[0080] Examples of suitable colorants include, but are not limited to, titanium dioxide; iron oxides, such as black iron oxide; aluminium paste; aluminium powder such as aluminium flake; carbon black; ultramarine blue; phthalocyanines, such as phthalocyanine blue and phthalocyanine green; chromium oxides, such as chromium green oxide; graphite fibrils; ferried yellow; quindo red; and combinations thereof.

[0081] The colorant may comprise titanium dioxide.

[0082] The colorant, when present, may be used in the composition in any suitable amount. The composition may comprise at least 0.01 wt%, such as at least 0.05 wt%, such as at least 0.1 wt%, such as at least 0.2 wt%, such as at least 0.25 wt%, such as at least 0.3 wt%, or even at least 0.35 wt% based on the total weight of the composition. The composition may comprise up to 10 wt%, such as up to 7.5 wt%, such as up to 5 wt%, such as up to 2.5 wt%, such as up to 2 wt%, such as up to 1 .5 wt% colorant based on the total weight of the composition.

[0083] The composition may comprise from 0.01 to 10 wt%, such as from 0.05 to 10 wt%, such as from 0.1 to 10 wt%, such as from 0.2 to 10 wt%, such as from 0.25 to 10 wt%, such as from 0.3 to 10 wt%, or even from 0.35 to 10 wt% based on the total weight of the composition. The composition may comprise from 0.01 to 7.5 wt%, such as from 0.05 to 7.5 wt%, such as from 0.1 to 7.5 wt%, such as from 0.2 to 7.5 wt%, such as from 0.25 to 7.5 wt%, such as from 0.3 to 7.5 wt%, or even from 0.35 to 7.5 wt% based on the total weight of the composition. The composition may comprise from 0.01 to 5 wt%, such as from 0.05 to 5 wt%, such as from 0.1 to 5 wt%, such as from 0.2 to 5 wt%, such as from 0.25 to 5 wt%, such as from 0.3 to 5 wt%, or even from 0.35 to 5 wt% based on the total weight of the composition. The composition maycomprise from 0.01 to 2.5 wt%, such as from 0.05 to 2.5 wt%, such as from 0.1 to 2.5 wt%, such as from 0.2 to 2.5 wt%, such as from 0.25 to 2.5 wt%, such as from 0.3 to 2.5 wt%, or even from 0.35 to 2.5 wt% based on the total weight of the composition. The composition may comprise from 0.01 to 2 wt%, such as from 0.05 to 2 wt%, such as from 0.1 to 2 wt%, such as from 0.2 to 2 wt%, such as from 0.25 to 2 wt%, such as from 0.3 to 2 wt%, or even from 0.35 to 2 wt% based on the total weight of the composition. The composition may comprise from 0.01 to 1.5 wt%, such as from 0.05 to 1.5 wt%, such as from 0.1 to 1.5 wt%, such as from 0.2 to 1.5 wt%, such as from 0.25 to 1 .5 wt%, such as from 0.3 to 1 .5 wt%, or even from 0.35 to 1 .5 wt% based on the total weight of the composition.

[0084] The composition may comprise from 0.05 to 1 .5 wt% colorant based on the total weight of the composition.

[0085] The composition may comprise from 0.25 to 1 .5 wt% colorant based on the total weight of the composition.

[0086] The composition may comprise other optional materials well known in the art of formulating composition for sealing compounds, such as plasticizers, abrasion-resistant particles, anti-oxidants, hindered amine light stabilizers, UV light absorbers and stabilizers, surfactants, flow control agents, thixotropic agents, fillers, organic solvents, reactive diluents, catalysts, grind vehicles, lubricants, waxes and other customary auxiliaries. For example, the composition may comprise a slip agent, a wax, a silica, a propellant and / or combinations thereof.

[0087] The composition may further comprise a slip agent. Slip agents may typically be included to adjust the torque, i.e., in the case of closures which must be screwed or twisted onto the food and / or beverage packaging. Examples of suitable slip agents include, but are not limited to, fatty acids, such as stearic acid and oleic acid; silicone oils, such as dimethylpolysiloxane and methylhydrogenopolysiloxane; and combinations thereof.

[0088] Waxes and / or silicas may typically be included to obtain specific flow properties, for example to obtain a thixotropic composition. Propellants may typically be included where it is desired to obtain a foamed sealing compound. Suitable propellants include, but are not limited to, azodicarbonamides or sulfohydrazides.

[0089] Suitable lubricants will be well known to the person skilled in the art. Suitable examples of lubricants include, but are not limited to, carnauba wax and polyethylene type lubricants.

[0090] Surfactants may optionally be added to the composition in order to aid in flow and wetting of the substrate. Suitable surfactants will be well known to the person skilled in the art. The surfactant, when present, may be chosen to be compatible with food and / or beverage packaging applications. Suitable surfactants include, but are not limited to, alkyl sulphates (e.g., sodium lauryl sulphate); ether sulphates; phosphate esters; sulphonates; and their various alkali, ammonium, amine salts; aliphatic alcohol ethoxylates; alkyl phenol ethoxylates (e.g. nonyl phenol polyether); salts and / or combinations thereof.

[0091] The compositions are substantially free of covalent halogen-containing resin materials and precursors thereof. As used herein, a halogen-containing resin material refers to a material in which a halogen is covalently bound to the material. This is distinguished from a material in which a halogen atom is present as a counterion for ionic functionality, for example. Examples of covalent halogen-containing resin materials include, for example, polyvinyl chloride (PVC) resins. The compositions may be essentially free or may be completely free of covalent halogen-containing resin materials and precursors thereof. The covalent halogen-containing resin materials and precursors thereof mentioned above may not be added to the composition intentionally but may be present in trace amounts because of unavoidable contamination from the environment. By “substantially free” we mean to refer to compositions containing less than 1000 parts per million (ppm) of covalent halogen-containing resin materials and precursors thereof. By “essentially free” we mean to refer to compositions containing less than 100 ppm of covalent halogen-containing resin materials and precursors thereof. By “completely free” we mean to refer to compositions containing less than 20 parts per billion (ppb) of covalent halogen-containing resin materials and precursors thereof.

[0092] The polyol material and / or the non-blocked isocyanate material may be substantially free, may be essentially free or may be completely free of organic solvents. By “substantially free” we mean to refer to polyol materials and / or non-blocked isocyanate materials that contain less than 1 wt% of organic solvents based on the total weight of the polyol material and / or the nonblocked isocyanate material. By “essentially free” we mean to refer to polyol materials and / or non-blocked isocyanate materials that contain less than 0.5 wt% of organic solvents based on the total weight of the polyol material and / or the non-blocked isocyanate material. By “completely free” we mean to refer to polyol materials and / or non-blocked isocyanate materials that contain less than 0.05 wt% of organic solvents based on the total weight of the polyol material and / or the non-blocked isocyanate material.

[0093] The composition may comprise one or more liquid component(s). The composition may further comprise one or more solid, or powder, component(s), typically dispersed, suspended and / or dissolved in the liquid phase / component(s). The liquid component(s) may be present as a result of the use of one or more viscous component(s). For example, the liquid component(s) may be present as part of one or more of the components, i.e., raw ingredients, of the liquid composition and not directly added as a solvent.

[0094] The composition may be substantially free, may be essentially free or may be completely free of organic solvents. By “substantially free” we mean to refer to compositions that contain less than 1 wt% of organic solvents based on the total weight of the composition. By “essentially free” we mean to refer to compositions that contain less than 0.5 wt% of organic solvents based on the total weight of the composition. By “completely free” we mean to refer to compositions that contain less than 0.05 wt% of organic solvents based on the total weight of the composition.

[0095] The compositions may be substantially free of bisphenol A (BPA) and derivatives thereof. The compositions may be essentially free or may be completely free of bisphenol A (BPA) andderivatives thereof. Derivatives of bisphenol A include, for example, bisphenol A diglycidyl ether (BADGE). The compositions may also be substantially free of bisphenol F (BPF) and derivatives thereof. The compositions may be essentially free or may be completely free of bisphenol F (BPF) and derivatives thereof. Derivatives of bisphenol F include, for example, bisphenol F diglycidyl ether (BPFGE). The compositions may also be substantially free of bisphenol S (BPS) and derivatives thereof. The compositions may be essentially free or may be completely free of bisphenol S (BPS) and derivatives thereof. Derivatives of bisphenol S include, for example, bisphenol S diglycidyl ether (BPSGE). The compounds or derivatives thereof mentioned above may not be added to the composition intentionally but may be present in trace amounts because of unavoidable contamination from the environment. By “substantially free” we mean to refer to compositions containing less than 1000 parts per million (ppm) of any of the compounds or derivatives thereof mentioned above. By “essentially free” we mean to refer to compositions containing less than 100 ppm of any of the compounds or derivatives thereof mentioned above. By “completely free” we mean to refer to compositions containing less than 20 parts per billion (ppb) of any of the compounds or derivatives thereof.

[0096] The compositions may be substantially free, essentially free or may be completely free of tin, for example of dialkyltin compounds, including oxides or other derivatives thereof. Examples of dialkyltin compounds include, but are not limited to, dibutyltindilaurate (DBTDL); dioctyltindilaurate; dimethyltin oxide; diethyltin oxide; dipropyltin oxide; dibutyltin oxide (DBTO); dioctyltinoxide (DOTO) or combinations thereof. By “substantially free” we mean to refer to compositions containing less than 1000 parts per million (ppm) of any of the compounds or derivatives thereof mentioned above. By “essentially free” we mean to refer to compositions containing less than 100 ppm of any of the compounds or derivatives thereof mentioned above. By “completely free” we mean to refer to compositions containing less than 20 parts per billion (ppb) of any of the compounds or derivatives thereof.

[0097] The compositions may be substantially free, may be essentially free or may be completely free of bromine. By “substantially free” we mean to refer to compositions containing less than 1000 parts per million (ppm) of bromine. By “essentially free” we mean to refer to compositions containing less than 100 ppm of bromine. By “completely free” we mean to refer to compositions containing less than 20 parts per billion (ppb) of bromine.

[0098] The compositions may be substantially free, may be essentially free or may be completely free of formaldehyde. By “substantially free” we mean to refer to compositions containing less than 1000 parts per million (ppm) of formaldehyde. By “essentially free” we mean to refer to compositions containing less than 100 ppm of formaldehyde. By “completely free” we mean to refer to compositions containing less than 20 parts per billion (ppb) of formaldehyde. The compositions may comprise 0 wt% of formaldehyde.

[0099] The composition may suitably be applied to a closure for packaging. The composition may be applied to a closure for packaging at any suitable temperature. The composition may be applied to a closure at an application temperature, T. For the avoidance of doubt, by “applicationtemperature, T” is meant the temperature at the point at which the composition is applied to the substrate. For example, if the composition is applied to the substrate at room temperature, then the application temperature, T, will be room temperature. If the composition is applied to the substrate at 40°C, then the application temperature, T, will be 40°C.

[0100] The composition may be liquid at the application temperature, T. By “liquid”, and like terms as used herein, in relation to the composition is meant that the composition is a fluid that is able to flow freely and has a near constant volume at room temperature. The liquid composition may have a low or medium viscosity, such as a low viscosity, at the application temperature, T. By “low viscosity” is meant a composition having a viscosity from 1 to 10,000 mPa.s at the application temperature, T. By “medium viscosity” is meant a composition having a viscosity from 10,000 to 100,000 mPa.s at the application temperature, T.

[0101] The application temperature, T, may be at least 20, 30, 40 or 50°C. Thus, the composition may be liquid at least 20, 30, 40 or 50°C.

[0102] The application temperature, T, may be room temperature. Thus, the composition may be liquid at room temperature.

[0103] The application temperature, T, may be 20°C. Thus, the composition may be liquid at 20°C.

[0104] The application temperature, T, may be 30°C. Thus, the composition may be liquid at 30°C.

[0105] The application temperature, T, may be 40°C. Thus, the composition may be liquid at 40°C.

[0106] It may be necessary to heat the composition to the application temperature, T, prior to application. For example, when the compound is not a liquid at room temperature it may be necessary to heat the composition to the application temperature, T, prior to application such that it is a liquid upon application to the substrate. It will be appreciated by a person skilled in the art that when the composition is a liquid at room temperature, it may not be necessary, although it is not excluded, to heat the composition prior to application to the substrate. If required, the liquid composition may be heated to the application temperature, T, at any suitable time prior to application to the substrate, such as up to 1 hour, up to 30 minutes, up to 10 minutes, up to 5 minutes, up to 2 minutes, or up to 1 minute prior to application to the substrate. It will be appreciated by a person skilled in the art that, if required, the composition should be heated for a suitable time so as to ensure that the composition is a liquid prior to application to the substrate (at the application temperature, T).

[0107] The composition may have any suitable viscosity at the application temperature, T. The composition may have a viscosity of up to 100,000 mPa.s, such as up to 50,000 mPa.s, such as up to 10,000 mPa.s, such as up to 5,000 mPa.s, such as up to 1,000 mPa.s at the application temperature, T. The composition may have a viscosity of at least 100 mPa.s, such as at least 200 mPa.s, such as at least 300 mPa.s, such as at least 400 mPa.s, such as at least 500 mPa.s at the application temperature, T. The composition may have a viscosity from 1 to 100,000mPa.s, such as from 100 to 100,000 mPa.s, such as from 200 to 100,000 mPa.s, such as from 300 to 100,000 mPa.s, such as from 400 to 100,000 mPa.s, such as from 500 to 100,000 mPa.s at the application temperature, T. The composition may have a viscosity from 1 to 50,000 mPa.s, such as from 100 to 50,000 mPa.s, such as from 200 to 50,000 mPa.s, such as from 300 to 50,000 mPa.s, such as from 400 to 50,000 mPa.s, such as from 500 to 50,000 mPa.s at the application temperature, T. The composition may have a viscosity from 1 to 10,000 mPa.s, such as from 100 to 10,000 mPa.s, such as from 200 to 10,000 mPa.s, such as from 300 to 10,000 mPa.s, such as from 400 to 10,000 mPa.s, such as from 500 to 10,000 mPa.s at the application temperature, T. The composition may have a viscosity from 1 to 5,000 mPa.s, such as from 100 to 5,000 mPa.s, such as from 200 to 5,000 mPa.s, such as from 300 to 5,000 mPa.s, such as from 400 to 5,000 mPa.s, such as from 500 to 5,000 mPa.s at the application temperature, T. The composition may have a viscosity from 1 to 1 ,000 mPa.s, such as from 100 to 1 ,000 mPa.s, such as from 200 to 1 ,000 mPa.s, such as from 300 to 1 ,000 mPa.s, such as from 400 to 1 ,000 mPa.s, such as from 500 to 1 ,000 mPa.s at the application temperature, T.

[0108] The composition may have a viscosity of 100 to 15,000 mPa.s at the application temperature, T. The composition may have a viscosity of 100 to 5,000 mPa.s at the application temperature, T. The composition may have a viscosity of 200 to 2,500 mPa.s at the application temperature, T. The composition may have a viscosity of 300 to 2,000 mPa.s at the application temperature, T.

[0109] The composition may have a first viscosity, V1 , at room temperature and a second viscosity, V2, at the application temperature, T. The first viscosity, V1, may be higher than the second viscosity, V2.

[0110] For example, the composition may have a first viscosity, V1, at 20°C. The composition may have a first viscosity, V1, of 800 to 2,500 mPa.s at 20°C. The composition may have a first viscosity, V1 , of 1 ,000 to 2,000 mPa.s at 20°C.

[0111] For example, the composition may have a second viscosity, V2, at 40°C. The composition may have a second viscosity, V2, of 100 to 700 mPa.s at 40°C. The composition may have a second viscosity, V2, of 200 to 600 mPa.s at 40°C.

[0112] As reported herein, the viscosity was determined in accordance with DIN 53019 / 1 at a shear rate of 10 s’1. All values for viscosity reported herein were measured in this way unless specified otherwise.

[0113] The composition may be provided in any suitable form. The composition may be a one component (“1 K”) or a multi-component composition, such as a two component (“2K”) composition. A 1 K composition will be understood as referring to a composition wherein all the components are maintained in the same container after manufacture, during storage, etc. A 1 K composition can be applied to a substrate and cured by any conventional means, such as by heating, forced air, radiation cure and the like. A 2K, or multi- component, composition will be understood as referring to a composition wherein various components are maintained separately until just prior to application.

[0114] The composition may be a two component (“2K”) composition or a multi-component composition, such as a two component (“2K”) composition.

[0115] Thus, the composition may be provided as a two-component composition comprising a first part and a second part. The first part may comprise the polyol material and optionally one or more ingredients selected from catalysts, pigments, fillers and other customary auxiliaries (such as any of those defined herein). The second part may comprise the non-blocked isocyanate material.

[0116] When the composition is provided as a multi-part composition, such as a two-part composition, the parts, such as first part and second part, may be provided in any suitable form. One or each of the first and second parts may be a liquid at room temperature. One or each of the first and second parts may be a solid at room temperature. One of the parts may be a solid at room temperature and the other part may be a liquid at room temperature. For example, the first part may be in the form of a liquid and the second part may be in the form of a solid at room temperature. For example, the first part may be in the form of a solid and the first part may be in the form of a liquid at room temperature. The first and second parts may have substantially the same viscosity at room temperature or may have different viscosities at room temperature.

[0117] At least one of the first and second parts may suitably be a liquid at the application temperature, T. For example, the first part and / or the second part may be a liquid at the application temperature, T. For example, the first part and the second part may be a liquid at the application temperature, T. The first part and the second part may have substantially the same viscosity at the application temperature, T. For the avoidance of doubt, when one of the parts is solid, or substantially solid, at the application temperature, T, the composition should typically be suitable to be applied to the substrate as a liquid upon mixing of the first and second parts (at the application temperature, T).

[0118] When the composition is provided as a multi-part composition, such as a two-part composition, the parts, such as first part and second part, are suitably mixed prior to application to the substrate, i.e., closure. The parts, such as first part and second part, may be mixed at any suitable time prior to application to the substrate, such as up to 1 hour, up to 30 minutes, up to 10 minutes, up to 5 minutes, up to 2 minutes, or up to 1 minute prior to application to the substrate. The parts, such as first part and second part, may be mixed immediately prior to application to the substrate. The parts, such as first part and second part, may be mixed by any suitable method. Suitable methods will be known to a person skilled in the art and include static and / or dynamic mixing. The parts, such as first part and second part, may suitably be mixed to homogenization. The parts may be mixed at room temperature or may be mixed at the application temperature, T, for example the parts may be mixed at the application temperature, T.

[0119] The composition may be a curable composition. By “curable composition”, and like terms as used herein, is meant that the composition has an initial state at the application temperature,T, and a final state in which the composition has been transformed into a substantially continuous, coalesced state.

[0120] The composition may be cured by any suitable method. For example, the composition may be cured by heat curing, by chemical curing or by a combination thereof.

[0121] The composition may be cured heat curing. The composition, when heat cured, may be cured at any suitable temperature. The composition, when heat cured, may be cured at temperatures from 120 to 300 °C, such as from 140 to 280 °C, such as from 160 to 260 °C, such as from 180 to 240 °C, such as from 200 to 240 °C, or even from 200 to 220 °C.

[0122] The composition is suitably cured, such as by heating, to form a sealing compound. It will be understood therefore that a sealing compound, or like terms as used and described herein, refers to a cured material that is derived from the compositions of the present invention.

[0123] By “sealing compound”, and like terms as used herein, is meant a material disposed on an interior surface of a closure to aid sealing of the closure to a food and / or beverage package (or container). For example, the sealing compound may be operable to hermetically seal the closure to the food and / or beverage package (or container). A sealing compound may also be referred to as a sealing liner or a gasket.

[0124] The terms “sealing compound”, “sealing liner”, “cured composition”, “compound” and “gasket” may be used interchangeably herein.

[0125] Thus, there is also provided a method for producing a closure for packaging, such as for food and / or beverage packaging, the method comprising the steps of:(iii) providing a closure for packaging, such as for food and / or beverage packaging, the closure having an interior and an exterior surface;(ii) applying a composition according to the present invention to at least a portion of the interior surface of the closure at an application temperature, T, wherein the composition is liquid at the application temperature, T; and(iii) at least partially curing the composition to form a sealing compound.

[0126] As already defined herein, the application temperature, T, may be at least 20, 30 or 40 °C. The application temperature, T, may be from 20 to 80°C, such as from 20 to 70°C, such as from 20 to 60°C, such as from 20 to 50°C. The application temperature, T, may be from 30 to 80°C, such as from 30 to 70°C, such as from 30 to 60°C, such as from 30 to 50°C. The application temperature, T, may be from 40 to 80°C, such as from 40 to 70°C, such as from 40 to 60°C, such as from 40 to 50°C.

[0127] The sealing compound may have any suitable Shore A hardness. The sealing compound may have a Shore A hardness of at least 10, such as at least 15, such as at least 20, such as at least 25, such as at least 30, such as at least 35, such as at least 40, such as at least 45, such as at least 50, such as at least 55, such as at least 60, such as at least 65, such as at least 70. The sealing compound may have a Shore A hardness of up to 100, such as up to 95, such as up to 90.

[0128] The sealing compound may have a Shore A hardness from 10 to 100, such as from 15 to100, such as from 20 to 100, such as from 25 to 100, such as from 30 to 100, such as from 35 to 100, such as from 40 to 100, such as from 45 to 100, such as from 50 to 100, such as from 55 to 100, such as from 60 to 100, such as from 65 to 100, such as from 70 to 100. The sealing compound may have a Shore A hardness from 10 to 95, such as from 15 to 95, such as from 20 to 95, such as from 25 to 95, such as from 30 to 95, such as from 35 to 95, such as from 40 to 95, such as from 45 to 95, such as from 50 to 95, such as from 55 to 95, such as from 60 to 95, such as from 65 to 95, such as from 70 to 95. The sealing compound may have a Shore A hardness from 10 to 90, such as from 15 to 90, such as from 20 to 90, such as from 25 to 90, such as from 30 to 90, such as from 35 to 90, such as from 40 to 90, such as from 45 to 90, such as from 50 to 90, such as from 55 to 90, such as from 60 to 90, such as from 65 to 90, such as from 70 to 90.

[0129] The sealing compound may have a Shore A hardness from 20 to 100.

[0130] The sealing compound may have a Shore A hardness from 70 to 100.

[0131] Values for Shore A hardness as reported herein are measured at room temperature unless specified otherwise.

[0132] As reported herein, the Shore A hardness was determined according to ASTM D2240- 15(2021 ) (“Standard Test Method for Rubber Property — Durometer Hardness”). All values for Shore A hardness reported herein were measured in this way unless specified otherwise.

[0133] The compositions of the present invention are for a closure for packaging. Thus, the sealing compounds derived from the compositions of the present inventions are also for a closure for packaging.

[0134] A “package” or “packaging” (which terms may be used interchangeably herein) is anything used to contain another item, particularly for shipping from a point of manufacture to a consumer, and for subsequent storage by a consumer. A package will be therefore understood as something that is sealed so as to keep its contents free from deterioration until opened by a consumer. The manufacturer will often identify the length of time during which the food or beverage will be free from spoilage, which typically ranges from several months to years. Thus, the present “package” is distinguished from a storage container or bakeware in which a consumer might make and / or store food; such a container would only maintain the freshness or integrity of the food item for a relatively short period. A package according to the present invention can be made of metal or non-metal, for example, plastic, laminate or glass, and be in any form. An example of a suitable package is a laminate tube. Another example of a suitable package is glassware, such as jars, bottles, etc. Another example of a suitable package is a metal can. The term “metal can” includes any type of metal can, container or any type of receptacle or portion thereof that is sealed by the food and / or beverage manufacturer to minimize or eliminate spoilage of the contents until such package is opened by the consumer. One example of a metal can is a food can; the term “food can(s)” is used herein to refer to cans, containers or any type of receptacle or portion thereof used to hold any type of food and / orbeverage. The term “metal can(s)” specifically includes food cans and also specifically includes “can ends” including “E-Z open ends”, which are typically stamped from can end stock and used in conjunction with the packaging of food and beverages. The term “metal cans” also specifically includes metal caps and / or closures such as bottle caps, screw top caps and lids of any size, lug caps, and the like. The metal cans can be used to hold other items as well, including, but not limited to, personal care products, bug spray, spray paint, and any other compound suitable for packaging in an aerosol can. The cans can include “two piece cans” and “three-piece cans” as well as drawn and ironed one-piece cans; such one piece cans often find application with aerosol products. Packages can also include plastic bottles, plastic tubes, laminates and flexible packaging, such as those made from PE, PP, PET and the like. Such packaging could hold, for example, food, toothpaste, personal care products, cosmetic products, pharmaceutical products and the like.

[0135] The packaging may contain any suitable product(s). Suitable examples of food and / or beverage products that may be contained in the packages of the present invention include, but are not limited to, acid-based food or beverages, milk-based products, meat-based products, onions, sauerkraut, fish in sauce, marinades, mussels, fruits in sweet sauces, energy drinks, coffee drinks, soups, mustard, mayonnaise, ketchup, salad dressings, pickled vegetables, etc.

[0136] The packaging may also be used to contain non-food products, such as hair spray, hair dye, paints and stains, joint compound, concrete mixes, glue, cleaning compositions, etching compositions, pharmaceuticals, nutraceuticals, fertilizers, and the like.

[0137] The packaging may be food and / or beverage packaging.

[0138] The packaging may be packaging for personal care products.

[0139] The packaging may comprise metal, plastic and / or glass.

[0140] Closures in accordance with the present invention include any closure, lid, cap, etc. that is meant to seal the opening of package (or container), such as a food and / or beverage package (or container). Closures include, but are not limited to, caps; lids; crown corks for glassware, such as jars, bottles, etc.; twist-off closures (also known as screw closures); roll-on closures for glassware, such as jars, bottles, etc.; pilfer-proof closures; pull-off closures for single use packaging, such as bottles, cans, etc.; and easy-peel lids; as well as further closures customary in the packaging industry for cans, bottles, tubs, barrels and the like.

[0141] The closure may be a rigid metal closure, for example, a twist-off metal closure which may include lugs or threads, for example, which are operable to engaged with the packaging (or container). Such twist-off metal closures may be used with plastic or glass packaging (or containers), such as jars or bottles for example, which are configured to engage with the threads, lugs, or any other suitable other engagement means of the closure.

[0142] The closure may be formed from any suitable material. For example, the closure may comprise plastic and / or metal, such as metal. Examples of suitable metals include, but are not limited to, aluminium; aluminium alloy; black plate; steel; tinplate; tinplate pre-treated with a protective material such as chromium, titanium, titanate and / or aluminium; tin-free steel (TFS);galvanised steel, such as for example electro-galvanised steel; iron alloys, which may optionally be provided with a passivation coating based on nickel, chromium and / or tin compounds and combinations thereof.

[0143] The closures may be formed via any suitable method. For example, the closure may be formed from coiled metal stock. Suitable methods for forming a closure will be known to a person skilled in the art. For example, the closure may be formed by stamping, drawing, redrawing, wall ironing, bending, beading, embossing, debossing, flanging, necking, stretching, blow-stretching, and / or any other suitable method.

[0144] The composition may be applied to an uncoated or a coated closure.

[0145] The composition may be applied to an uncoated closure. For the avoidance of doubt an uncoated closure extends to a surface that is cleaned prior to application.

[0146] The composition may be applied to a coated closure. For example, the composition may be applied on top of a coating layer or on top of a multi-layer coating system. For example, the composition may be applied on top of a primer. For example, the composition may be applied on top of a two, three, four, etc. layer coating system, such as on top of a two-layer coating system. The coating layers may be derived from any suitable coating composition such as those based on, for example, epoxy resins, the combination of epoxy and phenolic resins, polyacrylate resins; polyester resins; polyvinyl chloride (PVC) resins; polyurethane resins; polysiloxane resins; hydrocarbon resins; and / or combinations thereof. The coating layers may be derived from a coating composition based on an organosol. Suitable organosol will be well known to a person skilled in the art and include PVC, polyester and / or polyacrylate-based organosols. When the closure is coated with a multi-layer coating system, the primer layer may be derived from a polyester-based coating composition and the second, third, fourth, etc. coating layer(s) may independently be derived from an organosol-based coating composition, such as a PVC, polyester and / or polyacrylate-based organosol, such as a polyester and / or polyacrylate-based organosol.

[0147] The composition may be applied on top of a primer.

[0148] The composition may be applied on top of a two-layer coating system.

[0149] The composition may be applied to the closure once or multiple times.

[0150] When the closure is coated, each coating layer may independently be applied to the closure before or after the formation thereof. For example, one or more coating compositions may be applied to a substrate, such as a metal sheet, foil or the like, and at least partially cured to form a coating layer before the coated substrate is formed into the final closure (via one or more of the methods described herein, or otherwise). Alternatively or additionally, one or more coating compositions may be applied to the closure after the formation thereof and at least partially cured to form a coating layer.

[0151] When the closure is coated, each coating composition, from which the coating layer is suitably derived, may be applied to the closure by any suitable method. Methods of applying the coating compositions will be well known to a person skilled in the art. Suitable applicationmethods include, but are not limited to, electrocoating such as electrodeposition; spraying; electrostatic spraying; dipping; rolling; brushing; and the like.

[0152] The composition may suitably be applied to the interior surface of the closure. It will be appreciated that when the composition is applied to a coated closure, the one or more coating layers of the coated closure may also suitably be applied to the interior surface of the closure.

[0153] The composition may be applied to the interior surface of the closure by any suitable method. For example, composition may be applied to the interior surface of the closure using the "flow-in process" (as known to a person skilled in the art). In this process the composition is pressed or sprayed at slightly elevated temperature, typically about 40 °C, in the uncured state from one or more nozzles into the closure parts, which are rotated at a high speed of rotation with the inside facing upwards on a suction cup or the like. The composition is converted into the desired shape and form as a result of the centrifugal forces. After this ‘‘flowing-in’’ process is complete, the composition is suitably cured to form the sealing compound.

[0154] The compositions are suitably applied to the interior surface of the closure. For the avoidance of doubt, by ‘‘interior surface”, and like terms as used herein, in relation to a closure is meant the surface of the closure that is on the inside of the food and / or beverage package, i.e., forms the food and / or beverage-contact surface, upon fitting of the closure to said food and / or beverage package (or container). It will be appreciated that by applying the compositions to the interior surface of the closure means that, upon cure to form a sealing compound, that the sealing compound is operable to hermetically seal the food and / or beverage package (or container) upon fitting of the closure to said food and / or beverage package (or container).

[0155] The composition may be applied to at least a portion of the interior surface of the closure, such as to a portion of the interior surface to the closure. For example, the composition may be applied to a portion of the interior surface of the closure such that it forms an annular gasket that enhances the seal between the closure and a food and / or beverage package (or container). The gasket suitably sealingly engages the package (or container), such as sealingly engages a rim thereof, when the closure is fitted onto the package (or container).

[0156] There is also provided a closure for packaging, such as for food and / or beverage packaging, produced by a method comprising the steps of:(i) providing a closure for packaging, such as for food and / or beverage packaging, the closure having an interior and an exterior surface;(ii) applying a composition according to the present invention to at least a portion of the interior surface of the closure at an application temperature, T, wherein the composition is liquid at the application temperature, T; and(iii) at least partially curing the composition to form a sealing compound.

[0157] The application temperature, T, is as already defined herein.

[0158] There is also provided a closure for packaging, such as for food and / or beverage packaging, the closure having disposed on at least a portion thereof a sealing compound, the sealing compound being derived from a composition according to the present invention.

[0159] There is also provided packaging, such as for food and / or beverage packaging, comprising a closure, the closure having disposed on at least a portion thereof a sealing compound, the sealing compound being derived from a composition according to the present invention.

[0160] The term "alk” or “alkyl", as used herein unless otherwise defined, relates to saturated hydrocarbon radicals being straight, branched, cyclic or polycyclic moieties or combinations thereof and contain 1 to 20 carbon atoms, such as 1 to 10 carbon atoms, such as 1 to 8 carbon atoms, such as 1 to 6 carbon atoms, or even 1 to 4 carbon atoms. These radicals may be optionally substituted with a chloro, bromo, iodo, cyano, nitro, OR19, OC(O)R20, C(O)R21, C(O)OR22, NR23R24, C(O)NR25R26, SR27, C(O)SR27, C(S)NR25R26, aryl or Het, wherein R19to R27each independently represent hydrogen, aryl or alkyl, and / or be interrupted by oxygen or sulphur atoms, or by silano or dialkylsiloxane groups. Examples of such radicals may be independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tertbutyl, 2-methylbutyl, pentyl, iso-amyl, hexyl, cyclohexyl, 3-methylpentyl, octyl and the like. The term “alkylene”, as used herein, relates to a bivalent radical alkyl group as defined above. For example, an alkyl group such as methyl which would be represented as -CH3, becomes methylene, -CH2-, when represented as an alkylene. Other alkylene groups should be understood accordingly.

[0161] The term “alkenyl”, as used herein, relates to hydrocarbon radicals having, such as up to 4, double bonds, being straight, branched, cyclic or polycyclic moieties or combinations thereof and containing from 2 to 18 carbon atoms, such as 2 to 10 carbon atoms, such as from 2 to 8 carbon atoms, such as 2 to 6 carbon atoms, or even 2 to 4 carbon atoms. These radicals may be optionally substituted with a hydroxyl, chloro, bromo, iodo, cyano, nitro, OR19, OC(O)R20, C(O)R21, C(O)OR22, NR23R24, C(O)NR25R26, SR27, C(O)SR27, C(S)NR25R26, or aryl, wherein R19to R27each independently represent hydrogen, aryl or alkyl, and / or be interrupted by oxygen or sulphur atoms, or by silano or dialkylsiloxane groups. Examples of such radicals may be independently selected from alkenyl groups include vinyl, allyl, isopropenyl, pentenyl, hexenyl, heptenyl, cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, 1 -propenyl, 2-butenyl, 2- methyl-2-butenyl, isoprenyl, farnesyl, geranyl, geranylgeranyl and the like. The term “alkenylene”, as used herein, relates to a bivalent radical alkenyl group as defined above. For example, an alkenyl group such as ethenyl which would be represented as -CH=CH2, becomes ethenylene, -CH=CH-, when represented as an alkenylene. Other alkenylene groups should be understood accordingly.

[0162] The term "alkynyl", as used herein, relates to hydrocarbon radicals having, such as up to 4, triple bonds, being straight, branched, cyclic or polycyclic moieties or combinations thereof and having from 2 to 18 carbon atoms, such as 2 to 10 carbon atoms, such as from 2 to 8 carbon atoms, such as from 2 to 6 carbon atoms, or even from 2 to 4 carbon atoms. These radicals may be optionally substituted with a hydroxy, chloro, bromo, iodo, cyano, nitro, OR19, OC(O)R20, C(O)R21, C(O)OR22, NR23R24, C(O)NR25R26, SR27, C(O)SR27, C(S)NR25R26, or aryl,wherein R19to R27each independently represent hydrogen, aryl or lower alkyl, and / or be interrupted by oxygen or sulphur atoms, or by silano or dialkylsiloxane groups. Examples of such radicals may be independently selected from alkynyl radicals include ethynyl, propynyl, propargyl, butynyl, pentynyl, hexynyl and the like. The term “alkynylene”, as used herein, relates to a bivalent radical alkynyl group as defined above. For example, an alkynyl group such as ethynyl which would be represented as -C=CH, becomes ethynylene, -C=C-, when represented as an alkynylene. Other alkynylene groups should be understood accordingly.

[0163] The term “aryl” as used herein, relates to an organic radical derived from an aromatic hydrocarbon by removal of one hydrogen, and includes any monocyclic, bicyclic or polycyclic carbon ring of up to 7 members in each ring, wherein at least one ring is aromatic. These radicals may be optionally substituted with a hydroxy, chloro, bromo, iodo, cyano, nitro, OR19, OC(O)R20, C(O)R21, C(O)OR22, NR23R24, C(O)NR25R26, SR27, C(O)SR27, C(S)NR25R26, or aryl, wherein R19to R27each independently represent hydrogen, aryl or lower alkyl, and / or be interrupted by oxygen or sulphur atoms, or by silano or dialkylsilcon groups. Examples of such radicals may be independently selected from phenyl, p-tolyl, 4-methoxyphenyl, 4-(tert- butoxy)phenyl, 3-methyl-4-methoxyphenyl, 4-fluorophenyl, 4-chlorophenyl, 3-nitrophenyl, 3- aminophenyl, 3-acetamidophenyl, 4-acetamidophenyl, 2-methyl-3-acetamidophenyl, 2-methyl-3- aminophenyl, 3-methyl-4-aminophenyl, 2-amino-3-methylphenyl, 2,4-dimethyl-3-aminophenyl, 4-hydroxyphenyl, 3-methyl-4-hydroxyphenyl, 1 -naphthyl, 2-naphthyl, 3-amino-1 -naphthyl, 2- methyl-3-amino-1 -naphthyl, 6-amino-2-naphthyl, 4,6-dimethoxy-2-naphthyl, tetrahydronaphthyl, indanyl, biphenyl, phenanthryl, anthryl or acenaphthyl and the like. The term “arylene”, as used herein, relates to a bivalent radical aryl group as defined above. For example, an aryl group such as phenyl which would be represented as -Ph, becomes phenylene, -Ph-, when represented as an arylene. Other arylene groups should be understood accordingly.

[0164] For the avoidance of doubt, the reference to alkyl, alkenyl, alkynyl, aryl or aralkyl in composite groups herein should be interpreted accordingly, for example the reference to alkyl in aminoalkyl or alk in alkoxyl should be interpreted as alk or alkyl above etc.

[0165] As used herein, unless otherwise expressly specified, all numbers such as those expressing values, ranges, amounts or percentages may be read as if prefaced by the word "about", even if the term does not expressly appear. Also, the recitation of numerical ranges by endpoints includes all integer numbers and, where appropriate, fractions subsumed within that range (e.g. 1 to 5 can include 1 , 2, 3, 4 when referring to, for example, a number of elements, and can also include 1.5, 2, 2.75 and 3.80, when referring to, for example, measurements). The recitation of end points also includes the end point values themselves (e.g. from 1.0 to 5.0 includes both 1.0 and 5.0). Any numerical range recited herein is intended to include all subranges subsumed therein.

[0166] Singular encompasses plural and vice versa. For example, although reference is made herein to "a" polyol material, “a” non-blocked isocyanate material, “an” isocyanate, and the like, one or more of each of these and any other components can be used. As used herein, the term"polymer" refers to oligomers and both homopolymers and copolymers, and the prefix "poly" refers to two or more.

[0167] The terms "comprising", "comprises" and "comprised of” as used herein are synonymous with "including", "includes" or "containing", "contains", and are inclusive or open-ended and do not exclude additional, non-recited members, elements or method steps. Additionally, although the present invention has been described in terms of “comprising”, the coating compositions detailed herein may also be described as “consisting essentially of” or “consisting of”.

[0168] As used herein, the term "and / or," when used in a list of two or more items, means that any one of the listed items can be employed by itself or any combination of two or more of the listed items can be employed. For example, if a list is described as comprising group A, B, and / or C, the list can comprise A alone; B alone; C alone; A and B in combination; A and C in combination, B and C in combination; or A, B, and C in combination.

[0169] All of the features contained herein may be combined with any of the above aspects in any combination.

[0170] For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the following examples.ExamplesExamples 1 and 2

[0171] Examples 1 and 2, which are each PVC-free compositions in accordance with the present invention, were prepared according to the formulations in Table 1. The compositions of examples 1 and 2 are each liquid at room temperature. All amounts are given in parts by weight (pbw) unless specified otherwise.Table 1 : Formulation of Examples 1 and 21a trifunctional polypropylene ether polyol commercially available from Covestro2a linear polypropylene ether polyol commercially available from Covestro3an aliphatic polyisocyanate (low-viscosity HDI trimer) commercially available from Covestro4liquid aliphatic polyisocyanate based on hexamethylene diisocyanate commercially available from Vencorex Chemicals; 23.5 ± 1 .0% NCO content5tetra-n-butyl titanate catalyst commercially available from Dorf Ketal6titanium dioxide commercially available from Tronox7additive commercially available from BYK ChemieExample 3

[0172] Example 3, which is a PVC-free liquid composition in accordance with the present invention, was prepared in accordance with Table 2 and by the following method.

[0173] Components 1-4 were mixed for 10 minutes with mixing at 2,000 rpm. Then, components 5-8 were added and the mixture was further stirred for 10 minutes at 20 rpm to form a dispersion. After this time, component 9 was added. The mixture was then stirred for 30 minutes at 2,000 rpm followed by a further 5 minutes at 20 rpm.Table 2: Formulation of Example 31a trifunctional polypropylene ether polyol commercially available from Covestro2a linear polypropylene ether polyol commercially available from Covestro3an aliphatic polyisocyanate (low-viscosity HDI trimer) commercially available from Covestro4tetra-n-butyl titanate catalyst commercially available from Dorf Ketal5titanium dioxide commercially available from Tronox6additive commercially available from BYK ChemieComparative Example 1

[0174] Comparative example 1 is XG-DR283, a 1 K polyurea-based composition comprising a caprolactam-blocked isocyanate commercially available from PPG. XG-DR283 is a liquid at room temperature and is PVC-free.

[0175] The compositions were tested in accordance with the following test methods.

[0176] Pot life: the homogenized compound was placed on a plate system in a rotation viscometer. The viscosity was measured continuously at a 50 rpm. The pot life of the material was determined as the point when the viscosity reached double the initial viscosity value.

[0177] Closure preparation: 0.6 to 0.9 grams (g) of each of the compounds was applied with a nozzle inside the compound canal of a 63 mm Twist-Off-Lid. The compounds were cured in accordance with the temperature and time parameters set out in Table 3.

[0178] Overall migration: total migration was tested in accordance with Commission Regulation (EU) No 10 / 2011 of 14 January 2011. The closures were twisted onto 100 mL glass jars filled with isooctane (filtered through 0.2 pm PTFE hydrophobic membrane filters). The jars were clamped between two stainless steel plates to avoid leakage of the isooctane during processing and storage. The jars were processed by pasteurization and / or sterilization at temperatures of 100 or 131 °C (100°C for example 1 and comparative example 1 ; 131 °C for examples 2 and 3) and then stored at 40°C for 10 days. During processing and storage, the jars were kept upside down to ensure that the test liquid was in constant contact with the compound. After 10 days, the test liquid was transferred to previously weighed / tared glass jars. A precision balance with an accuracy of at least 0.0001g was used for weighing. The test liquid was evaporated at room temperature and the jars were then weighed again. The total migration of the non-volatile components corresponded to the balanced residue in the glass. Results were recorded as “above” or “below” the regulated overall migration limit of 10 mg per dm2of food contact surface.

[0179] Deformation: the closures were twisted onto 100 mL glass jars and sterilized with water at 121 °C. They were then placed in an autoclave to which overpressure was applied (start temp: 80 °C; end temp: 90°C; 60 min; 1.8 bar overpressure). After processing, the compounds were inspected visually and given a rating from -3 to +3 as follows:

[0180] Shore A hardness: the Shore A hardness was measured in accordance with ASTM D2240- 15(2021) (“Standard Test Method for Rubber Property - Durometer Hardness”) at room temperature.

[0181] The results are shown in Table 3.Table 3: Results

[0182] The results show that the compositions of the present invention have certain improved properties compared to the compositions of the art. In particular, the compositions of the present invention have lower total migration compared to the compositions of the art.

[0183] Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

[0184] All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive.

[0185] Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in thisspecification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

CLAIMS1. A composition for a closure for packaging, the composition comprising:(a) a polyol material; and(b) a non-blocked isocyanate material; wherein the composition is substantially free of covalent halogen-containing resin materials and precursors thereof.

2. The composition according to claim 1 , wherein the composition may be applied to a closure for packaging at an application temperature, T, and wherein the composition is liquid at the application temperature, T, for example at an application temperature of at least 20, 30 or 40°C.

3. The composition according to any one of claims 1 or 2, wherein the polyol material and / or the non-blocked isocyanate material are liquid at room temperature; and / or wherein the polyol material and / or the non-blocked isocyanate material has a viscosity from 50 to 9,500 mPa.s at 75°C.

4. The composition according to any one of claims 1-3, wherein the non-blocked isocyanate material has an isocyanate (NCO)-content of at least 5%, such as at least 20%.

5. The composition according to any one of claims 1-4, wherein the polyol material has a hydroxyl value (OHV) of at least 25 mg KOH / g.

6. The composition according to any one of claims 1-5, wherein the polyol material comprises a hydroxyl-functional polyester, polyolefin, polyacrylate, polyether, alkyd resin, polycarbonate, polycaprolactone, polyurethane, polysiloxanes, copolymers thereof and / or combinations thereof.

7. The composition according to claim 6, wherein the polyol material comprises one or more polyether polyol, such as one or more polypropylene glycol, polyester polyol, polycarbonate polyol and / or combinations thereof.

8. The composition according to any one of claims 1-7, wherein the non-blocked isocyanate material comprises a polyisocyanate based on hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, methylene-4,4'-bis(cyclohexyl isocyanate), bis-(4-isocyanatocyclohexyl)methane, methylene diphenyl diisocyanate, bis- (4-isocyanatophenyl) methane, tetramethyl-meta-xylylene diisocyanate, meta xylylenediisocyanate, para xylylene diisocyanate, cyclohexane diisocyanate, naphthalene diisocyanate, trimethyl hexamethylene diisocyanate and / or combinations thereof, such as a polyisocyanate based on hexamethylene-1 ,6-diisocyanate (HDI).

9. The composition according to any one of claims 1 -8, wherein at least a portion of the nonblocked isocyanate material is pre-reacted with the polyol material.

10. The composition according to any one of claims 1 -9, wherein the composition comprises a catalyst, such as a titanate-based catalyst, such as t-butyl titanate.11 . The composition according to any one of claims 1 -10, wherein the composition comprises a colorant.

12. The composition according to any one of claims 1 -11 , wherein the composition comprises a slip agent.

13. The composition according to any one of claims 1 -12, wherein the composition comprises at least a first part and a second part, wherein the polyol material is present in one part of the composition and at least a portion of the non-blocked isocyanate material is provided in another part of the composition.

14. The composition according to claim 13, wherein the polyol material is pre-reacted with a portion of the non-blocked isocyanate material.

15. The composition according to any one of claims 1-14, wherein the molar ratio of hydroxyl groups to isocyanate groups is greater than 1.

16. The composition according to any one of claims 1-15, wherein the composition is substantially free of bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS), bisphenol A diglycidyl ether (BADGE), bisphenol F diglycidyl ether (BFDGE) and bisphenol S diglycidyl ether (BSDGE).

17. The composition according to any one of claims 1 -16, wherein the polyol material and / or the non-blocked isocyanate material is substantially free of organic solvents.

18. The composition according to any one of claims 1-17, wherein the composition is substantially free of isocyanate blocking agents.

19. A method for producing a closure for packaging, the method comprising the steps of:(a) providing a closure having an interior and an exterior surface;(b) applying a composition according to any one of claims 1-18 to at least a portion of the interior surface of the closure at an application temperature, T, wherein the composition is liquid at the application temperature, T; and(c) at least partially curing the composition to form a sealing compound.

20. The method according to claim 19, wherein the application temperature is at least 20, 30, or 40°C.

21. The method according to any one of claims 19 or 20, wherein the composition is applied to a coated closure.

22. A closure for packaging produced according to the method of any one of claims 19-21 .

23. A closure for packaging, the closure having disposed on at least a portion thereof a sealing compound, the sealing compound being derived from a composition according to any one of claims 1 -18.

24. Packaging comprising a closure according to any one of claims 22 or 23.

25. The composition according to any one of claims 1 -18, the method according to any one of claims 19-21 , the closure according to any one of claims 22 or 23, or the packaging according to claim 24, wherein the packaging is food and / or beverage packaging.

26. The composition according to any one of claims 1 -18 or 25, the method according to any one of claims 19-21 or 25, the closure according to any one of claims 22, 23 or 25, or the packaging according to any one of claims 24 or 25, wherein the closure comprises a metal.

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