A post repair coating composition

Abstract

A post repair coating composition for a food or beverage package, the coating composition comprising: a) an acrylic material having oxirane-functionality; and b) a polyamine material, wherein the coating composition is substantially free of bisphenol A (BPA), bisphenol F (BPF) and derivatives thereof.

Description

[0001] A Post Repair Coating Composition

[0002] Field of the Invention

[0003]

[0001] The present invention relates to a post repair coating composition, in particular to a post repair coating composition comprising an acrylic material having oxirane-functionality and a polyamine material, wherein the coating composition is substantially free of bisphenol A (BPA), bisphenol F (BPF) and derivatives thereof. The present invention further relates to a food or beverage can comprising a surface having a coating on at least a portion thereof, the coating being derived from the post repair coating composition. The present invention further relates to a method of repairing a score line on a food or beverage can, the method comprising applying to the score line the post repair coating composition.

[0004] Background of the Invention

[0005]

[0002] Metal containers are being equipped more and more with so-called easy open ends (EOEs) in which a user accesses the interior of the container by piercing the container in a predetermined manner, without the need for a separate opening device. Such easy open ends are routinely used in food and beverage cans.

[0006]

[0003] The principle of easy opening is obtained by reducing the thickness of the metal to thereby provide a score line which is weaker and susceptible to opening. During the scoring operation, which is often achieved by stamping with a punch, any external varnish layers present on the surface are cut and therefore the corrosion resistance of the metal substrate is compromised. This is particularly problematic in a context where: i) the metal has been stressed and therefore its resistance to corrosion is weakened; ii) the tin layer of the tinplate (where this is the substrate) is also cut; iii) the next treatment step of the packaging is sterilisation, where the presence of heat and high humidity will create high corrosion conditions; and / or iv) the container is at the beginning of its life cycle which has a minimum of two years.

[0007]

[0004] The corrosion resistance of the metal substrate may be restored by the application of a repair coating to the score line. This coating is often applied by spraying and in particular by an airless spray process.

[0008]

[0005] Current repair formulations are generally based on a crosslinkable resin, such as an epoxy resin or acrylic resin. These compositions are characterised by high volatile organic compounds (VOC), a low cross-linkage speed and a limited pot life (from a few hours to a week), as well as high levels of side product being produced.

[0009]

[0006] It is desired to provide coatings with reduced levels of volatile organic content (VOC) when compared to the current compositions.

[0010]

[0007] In addition, epoxy-based coatings are prepared from monomers such as bisphenol A and bisphenol A diglycidyl ether (“BADGE”). BPA is perceived as being harmful to human health and it is therefore desirable to eliminate it from coatings. Derivatives of BPA such as diglycidyl ethers of bisphenol A (BADGE), epoxy novolak resins and polyols prepared from BPA and bisphenol F (BPF) are also perceived to be problematic. Government authorities, particularly in Europe, are becoming even more restrictive on the amount of free BADGE or its by-products that are acceptable.

[0011]

[0008] It is an object of embodiments of the present invention to provide a solution to one or more of the above mentioned or other problems.

[0012] Summary of the Invention

[0013]

[0009] According to a first aspect of the present invention there is provided a post repair coating composition for a food or beverage package, the coating composition comprising: a) an acrylic material having oxirane-functionality; and b) a polyamine material, wherein the coating composition is substantially free of bisphenol A (BPA), bisphenol F (BPF) and derivatives thereof.

[0014]

[0010] The food or beverage package may be a food or beverage can. Thus, the post repair coating composition may be for a food or beverage can.

[0015]

[0011] There is also provided a food or beverage package, such as a food or beverage can, comprising a surface having a coating on at least a portion thereof, the coating being derived from a post repair coating composition comprising: a. an acrylic material having oxirane-functionality; and b. a polyamine material, wherein the coating composition is substantially free of bisphenol A (BPA), bisphenol F (BPF) and derivatives thereof.

[0016]

[0012] There is also provided a method of repairing a score line on a food or beverage package, such as a food or beverage can, the method comprising applying to the score line a post repair coating composition comprising: a. an acrylic material having oxirane-functionality; and b. a polyamine material, wherein the coating composition is substantially free of bisphenol A (BPA), bisphenol F (BPF) and derivatives thereof.

[0017]

[0013] The post repair coating composition may comprise a liquid carrier. The liquid carrier may comprise solvent.

[0018]

[0014] The post repair coating composition may be a two-component system, wherein the two- component system comprises a first component comprising the acrylic material (a) and a second component comprising the polyamine material (b).

[0019] Detailed Description of the Invention

[0020]

[0015] The post repair coating composition of the present invention comprises an acrylic material having oxirane-functionality. The post repair coating composition may comprise any suitable acrylic material (on the proviso that it is oxirane-functional). The acrylic material may typically be formed from a reaction mixture, the reaction mixture may comprise one or more acrylic monomer(s), for example selected from alkyl (alk)acrylate, alkyl (meth)acrylate, and / or (alk)acry lie acid.

[0021]

[0016] Suitable acrylic monomers will be well known to a person skilled in the art. The acrylic material may be formed from more than one acrylic monomer. Suitable acrylic monomers include, but are not limited to, alkyl (alk)acrylate, such as Ci to Ge alkyl (Ci to Ge alk)acrylate, for example, Ci to Ce alkyl (meth)acrylate, and (alk)acrylic acid, such as (Ci to Ge alk)acrylic acid.

[0022]

[0017] As used herein, “(alk)acrylate”, "(meth)acrylate" and like terms are used conventionally and herein to refer to both alkacrylate and acrylate, such as methacrylate and acrylate.

[0023]

[0018] Examples of suitable acrylic monomers include, but are not limited to, acrylic acid, methacrylic acid, methyl acrylate; methyl methacrylate; ethyl acrylate; ethyl methacrylate; propyl acrylate; propyl methacrylate; isopropyl methacrylate, butyl acrylate, including n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate and tert-butyl acrylate; butyl methacrylate, including n-butyl methacrylate, sec-butyl methacrylate, isobutyl methacrylate and tert-butyl methacrylate, pentyl acrylate, pentyl methacrylate, isoamyl acrylate, isoamyl methacrylate, hexyl acrylate, hexyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, decyl acrylate, decyl methacrylate, isodecyl acrylate, isodecyl methacrylate, lauryl acrylate, lauryl methacrylate, octyl acrylate, octyl methacrylate, nonyl acrylate, nonyl methacrylate, isobornyl acrylate, isobornyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, phenoxy ethyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, glycidyl methacrylate; the reaction product of (meth)acrylic acid reacted with an epoxy, such as the reaction product of (meth)acrylic acid reacted with Cardura (RTM) E10P glycidyl ester; ethylene glycol diacrylate; ethylene glycol dimethacrylate; 1 ,6-hexanediol diacrylate; 1 ,6-hexanediol dimethacrylate; 4-hydroxybutyl acrylate; 4-hydroxybutyl methacrylate; allyl methacrylate; benzyl acrylate; benzyl methacrylate; phosphate esters of 2-hydroxyethyl methacrylate; those sold under the trade name SIPOMER commercially available from Solvay) such as, for example SIPOMER PAM-100, SIPOMER PAM-200 and SIPOMER PAM-300 (phosphate esters of polypropylene glycol monoacrylate); and SIPOMER WAM, SIMPOMER WAM II and SIPOMER WAM E W50 (methacrylic monomer based on 46-50% methacrylamidoethyl ethylene urea), ureido (meth)acrylate (commercially available from BASF), rosin (meth)acrylate, cardanyl (meth)acrylate, cardanol (meth)acrylate, acrylamides such as, for example, acrylamide methacrylamide, N,N-dimethylacrylamide, N-ethylacrylamide, N-hydroxyethyl acrylamide, diacetone acrylamide, N,N-diethylacrylamide, N-isopropylacrylamide and N- isopropylmethacrylamide; 2-acrylamido-2-methyl-1 -propanesulfonic acid; silane-functional (alk)acrylic acids and / or (alk)acrylates such as, for example, 3-(trimethoxysilyl)propyl methacrylate (also known as silane A174, commercially available from Sigma Aldrich) and 3- (trimethoxysilyl)propyl acrylate (commercially available from Sigma Aldrich); and combinations thereof. Any other acrylic monomers known to those skilled in the art could also be used.

[0019] At least one of the acrylic monomers may comprise a functional group, such as a hydroxy group. The acrylic monomer may comprise a hydroxyl functional acrylic monomer. The acrylic monomer may comprise a hydroxyl functional alkyl(alk)acrylate, for example, hydroxyl functional Ci to Ce alkyl (Ci to Ge alk)acrylate, such as hydroxyl functional Ci to Ce alkyl (meth)acrylate or hydroxyl functional Ci to Ge alkyl (Ci to Ge alk)acrylate. Examples of suitable hydroxyl functional acrylic monomer(s) include, but are not limited to, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxymethyl acrylate, hydroxymethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, hydroxypentyl acrylate, hydroxypentyl methacrylate, hydroxyhexyl acrylate, hydroxyhexyl methacrylate, methyl 2-(hydroxymethyl)acrylate ethyl 2-(hydroxymethyl)acrylate, polyethylene glycol methacrylate and / or polypropylene glycol methacrylate. The hydroxyl functional acrylic monomer may comprise hydroxyethyl acrylate, hydroxyethyl methacrylate, the reaction product of (meth)acrylic acid reacted with an epoxy, such as the reaction product of (meth)acrylic acid with Cardura (RTM) E10P glycidyl ester, polyethylene glycol methacrylate and / or polypropylene glycol methacrylate.

[0024]

[0020] At least one acrylic monomer may comprise two or more ethylenically unsaturated groups, i.e., may be a multi-ethylenically unsaturated monomer. Examples of suitable multi- ethylenically unsaturated monomers include, but are not limited to, multi-ethylenically unsaturated (alk)acrylates, such as multi-ethylenically unsaturated (meth)acrylates, alkenyl (alk)acrylates, alkynyl (alk)acrylates, and combinations thereof. Examples of suitable multi- ethylenically unsaturated (alk)acrylates include, for example, polyhydric alcohol esters of acrylic acid or methacrylic acid. For example, the acrylic monomer may comprise two, three, four or more acrylate groups. For the avoidance of doubt, by “acrylate group”, and like terms as used herein, is meant salts and esters of acrylic acid, i.e. monomers having the structure R- C=CCOO-R1, wherein R represents hydrogen, alkyl, alkenyl alkynyl, aralkyl or aryl and R1represents hydrogen, alkyl, alkenyl alkynyl, aralkyl or aryl. The acrylic monomer may comprise a di(alk)acrylate. Suitable di(alk)acrylates will be known to a person skilled in the art. Examples of suitable di(alk)acrylates include, but are not limited to, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1 ,2-propanediol diacrylate, 1 ,3-propanediol diacrylate, 1 ,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,2-petanediol diacrylate, 1 ,3-petanediol diacrylate, 1 ,5-petanediol diacrylate, 1 ,2-hexanediol diacrylate, 1 ,3-hexanediol diacrylate, 1 ,4-hexanediol diacrylate, 1,6- hexanediol diacrylate, 1 ,2-propanediol dimethacrylate, 1 ,3-propanediol dimethacrylate, 1,3- butanediol dimethacrylate, 1 ,4-butanediol dimethacrylate, 1 ,2-petanediol dimethacrylate, 1,3- petanediol dimethacrylate, 1 ,5-petanediol dimethacrylate, 1 ,2-hexanediol dimethacrylate, 1,3- hexanediol dimethacrylate, 1 ,4-hexanediol dimethacrylate, 1,6-hexanediol dimethacrylate and combinations thereof. The acrylic monomer may comprise a tri(alk)acrylate. Suitable tri(alk)acrylates will be known to a person skilled in the art. Examples of suitable tri(alk)acrylates include, but are not limited to, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate and combinations thereof.

[0021] Examples of suitable alkenyl (alk)acrylates include, for example, allyl acrylate, allyl methacrylate, and combinations thereof.

[0025]

[0022] The reaction mixture from which the acrylic material is formed may further comprise one or more additional ethylenically unsaturated monomer(s). Suitable additional ethylenically unsaturated monomers will be known to a person skilled in the art. Examples of suitable additional ethylenically unsaturated monomers include, but are not limited to, aryl substituted ethylenically unsaturated monomers such as, for example, styrene, alpha-methyl styrene, 3,4- alpha-methyl styrene, 2-methyl styrene, 4-methyl styrene (vinyl toluene), 2,3-dimethyl styrene, 2-ethyl styrene, 4-tertbutylstyrene, 4-methoxystyrene, 4-phenylstyrene, 4-phenoxy styrene, 4- propyl styrene, 4-benzylstyrene, 4-cyclohexyl styrene, 4-dodecyl styrene, 4-(phenyl butyl)styrene, 2-methyl-4-isopopyl styrene, 2-ethyl-4-benzyl styrene, 4-chlorostyrene, 2,5- dichlorostyrene, 3,4-dichlorostyrene, 2,6-dichlorostyrene, 4-fluorostyrene, divinylbenzene, isopropyl styrene, t-butyl styrene, trans-beta-styrene, chloromethylstyrene, 4-hydroxystyrene, diglycidyloxymethylstyrene, 2,4-diglycidyloxymethylstyrene, 2,5-diglycidyloxymethylstyrene, 2,6- diglycidyloxymethylstyrene, 2,3,4-triglycidyloxymethylstyrene, 2,3,5-triglycidyl oxime styrene, 2,3,6-triglycidyloxymethylstyrene and 3,4,5-triglycidyloxymethylstyrene, 2,4,6- triglycidyloxymethylstyrene, unsaturated carboxylic acids or diacids (or anhydrides) such as, for examples, maleic acid (or anhydride) and itaconic acid (or anhydride), ethylenically unsaturated nitriles such as, for example, acrylonitrile or methacrylonitrile, vinyl esters such as, for example, vinyl acetate and vinyl propionate, alkenes, such as C2 to Ce alkenes, for example, ethene, propene, 1 -butene, 2-butene, 1 -pentene, 2-pentene, 1 -hexene, 2-hexene, 3-hexene, 1 -hetpene, 2-heptene, 3-heptene, 1 -octene, 2-octene, 3-octene, 4-octene and isobutylene, vinyl chloride, butadiene, isoprene, chloroprene, N-vinyl monomers such as, for example, N-vinyl pyrrolidone, N-vinyl caprolactam and N-vinyl acetamide, unsaturated fatty acid ester; allyl glycidyl ether, allyl ethyl ether, vinyl ether monomers such as, for example, methyl vinyl ether, ethyl vinyl ether, n- propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, t-butyl vinyl ether, pentyl vinyl ether, cyclopentyl vinyl ether, hexyl vinyl ether, cyclohexyl vinyl ether, 2-ethylhexyl vinyl ether, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, 1 ,4-butanediol divinyl ether, diethyleneglycol divinyl ether, triethyleneglycol divinyl ether, 1 ,4-cyclohexanedimethanol divinyl ether, 2-(2-hydroxyethyl) ethyl vinyl ether, octyl vinyl ether, benzyl vinyl ether, phenyl vinyl ether, phenethyl vinyl ether and allyl vinyl ether, vinylphosphoric acid (commercially available from Sigma Aldrich) and combinations thereof. The additional ethylenically unsaturated monomer(s) may comprise monomers, oligomers and / or polymers of the aforementioned monomers. For example, butadiene may be in the foaprm of a monomer or may be in the form of polybutadiene.

[0026]

[0023] The additional ethylenically unsaturated monomer(s) may comprise terpene monomers or derivatives thereof, rosin monomers or derivatives thereof, cardanol monomers or derivatives thereof. Examples of suitable terpene monomers or derivatives thereof include, but are not limited to, monoterpenes such as, for example, a-pinene, p-pinene, camphene, sabinene, limonene and myrcene, sesquiterpenes such as, for example, bisabolene and nerolidol, and diterpenes. Examples of suitable rosin monomers or derivates thereof include, but are not limited to, rosin, rosin acids, abietic acid, neabietic acid, palustric acid, pimaric acid, levopimaric acid, maleopimaric acid, fumaropimaric acid, isopimaric acid, rosin-formaldehyde resin, rosin alcohol and rosin phenol. Examples of suitable cardanol monomers or derivatives thereof of include, but are not limited to cardanol, anacardic acid, cardanol glycidyl ether, cardanol- formaldehyde resin, cardanol epoxies, cardanol phenols and cardanol alcohols.

[0027]

[0024] The additional ethylenically unsaturated monomer may comprise a hydroxyl functional ethylenically unsaturated monomer. The hydroxyl functional ethylenically unsaturated monomer may comprise N-hydroxyethyl acrylamide, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, 2-(2-hydroxyethyl) ethyl vinyl ether, and / or hydroxystyrene. The hydroxyl functional ethylenically unsaturated monomer may comprise the reaction product of (meth)acrylic acid with an epoxy (such as Cardura E10) and / or the reaction product of glycidyl methacrylate with a carboxylic acid functional component (such as a benzoic acid and / or an aliphatic acid, such as a aliphatic acid, for example).

[0028]

[0025] The one or more additional ethylenically unsaturated monomer(s) may comprise two or more ethylenically unsaturated groups, i.e., may be a multi-ethylenically unsaturated monomer. Examples of suitable multi-ethylenically unsaturated monomers (that are not (alk)acrylates) include, but are not limited to, diallyl phthalate, divinylbenzene, divinyltoluene, divinylnaphthalene, and combinations thereof.

[0029]

[0026] The reaction mixture from which the acrylic material is formed may be substantially free, may be essentially free or may be completely free of styrene. It will be appreciated, therefore, that the acrylic material may be substantially free, may be essentially free or may be completely free of styrene. By “substantially” free in relation to styrene, is meant that the acrylic material is formed from monomers which comprise less than 5 wt% of styrene based on the total weight of the monomers from which the acrylic material is formed. By “essentially free” in relation to styrene, is meant that the acrylic material is formed from monomers which comprise less than 1 wt% of styrene based on the total weight of the monomers from which the acrylic material is formed. By “completely free” in relation to styrene, is meant that the acrylic material is formed from monomers which comprise less than 0.01 wt% of styrene based on the total weight of the monomers from which the acrylic material is formed.

[0030]

[0027] The reaction mixture from which the acrylic material is formed may comprise no, i.e. 0 wt%, styrene based on the total solid weight of the monomers. The acrylic material, therefore, may be formed from monomers which comprise no, i.e., 0 wt%, styrene based on the total weight of the monomers from which the acrylic material is formed.

[0031]

[0028] The acrylic material may be completely free of styrene.

[0032]

[0029] The acrylic material may comprise any suitable amount of acrylic monomer. It will be appreciated that the acrylic material comprises, i.e., is formed from a reaction mixture comprising, at least one acrylic monomer. It will be appreciated that the acrylic material comprises, i.e., is formed from a reaction mixture comprising, at least one acrylic monomer having oxirane-functionality and / or at least one acrylic monomer having a group capable of reacting with another material to provide oxirane functionality. For example, the acrylic material may comprise, i.e., be formed from a reaction mixture comprising, at least one acrylic monomer having oxirane-functionality.

[0033]

[0030] The acrylic material may comprise at least 10 wt%, such as at least 20 wt%, such as at least 30 wt%, such as at least 40 wt%, such as at least 50 wt%, such as at least 60 wt%, such as at least 70 wt%, such as at least 75 wt% acrylic monomer, 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 97 wt%, such as at least 98 wt%, such as at least 99 wt%, or even >99 wt%, for example, at least 99.1 wt%, at least 99.5 wt% or at least 99.9 wt% acrylic monomer based on the total solid weight of the monomers from which the acrylic material is formed. The acrylic material may comprise 100 wt% acrylic monomer based on the total solid weight of the monomers from which the acrylic material is formed.

[0034]

[0031] The acrylic material has oxirane-functionality. The acrylic material may be provided with oxirane-functionality by any suitable means. For example, the acrylic material may be formed from one or more oxirane-functional monomers, such as from one or more ethylenically unsaturated oxirane-functional monomers, such as one or more a, p-ethylenically unsaturated monomers. The acrylic material may be formed from one or more oxirane-functional acrylic monomers.

[0035]

[0032] Suitable oxirane-functional monomers include monomers having a reactive carboncarbon double bond and an oxirane (i.e., a glycidyl) group. The oxirane-functional monomer may be a glycidyl ester of an a,p-unsaturated acid, or anhydride thereof (i.e., an oxirane group- containing a, p-ethylenically unsaturated monomer). Suitable a,p-unsaturated acids include monocarboxylic acids or dicarboxylic acids, for example. Examples of such carboxylic acids include, but are not limited to, acrylic acid, methacrylic acid, a-chloroacrylic acid, a-cyanoacrylic acid, p- methylacrylic acid (cratonic acid), a-phenylacrylic acid, p-acryloxypropionic acid, sorbic acid, a-chlorosorbic acid, angelic acid, cinnamic acid, p-chlorocinnamic acid, p-stearylacrylic acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid, maleic acid, fumaric acid, tricarboxyethylene, maleic anhydride, and combinations thereof. Examples of suitable oxirane-functional monomers include, but are not limited to, glycidyl (meth)acrylate, mono- and di-glycidyl itaconate, mono- and di-glycidyl maleate, mono- and di-glycidyl formate, allyl glycidyl ether, vinyl glycidyl ether, and combinations thereof.

[0036]

[0033] The oxirane-functional monomer may comprise glycidyl methacrylate.

[0037]

[0034] The acrylic material may be formed from a reaction mixture comprising glycidyl methacrylate.

[0038]

[0035] The acrylic material may be formed from a reaction mixture comprising one or more alkyl (alk)acrylate and glycidyl methacrylate.

[0039]

[0036] The acrylic material may be formed from a reaction mixture comprising butyl (meth)acrylate, methyl (meth)acrylate and glycidyl methacrylate.

[0037] The acrylic material may be formed from a reaction mixture comprising any suitable amount of oxirane-functional monomer. The acrylic material may be formed from a reaction mixture comprising at least 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 29, 29, or 30 wt% oxirane-functional monomer based on the total weight of monomers present. The acrylic material may be formed from a reaction mixture comprising up to 60, such as up to 50, such as up to 40, such as up to 35 wt% oxirane-functional monomer based on the total weight of monomers present. The acrylic material may be formed from a reaction mixture comprising from 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 29, 29, or 30 wt% to 60 wt% oxirane-functional monomer based on the total weight of monomers present. The acrylic material may be formed from a reaction mixture comprising from 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 29, 29, or 30 wt% to 50 wt% oxirane-functional monomer based on the total weight of monomers present. The acrylic material may be formed from a reaction mixture comprising from 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 29, 29, or 30 wt% to 40 wt% oxirane-functional monomer based on the total weight of monomers present. The acrylic material may be formed from a reaction mixture comprising from 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 29, 29, or 30 wt% to 35 wt% oxirane-functional monomer based on the total weight of monomers present.

[0040]

[0038] The acrylic material may be formed from a reaction mixture comprising from 15 to 35 wt% oxirane-functional monomer based on the total weight of monomers present.

[0041]

[0039] The acrylic material may be formed from a reaction mixture comprising from 20 to 35 wt% oxirane-functional monomer based on the total weight of monomers present.

[0042]

[0040] The acrylic material may comprise a solution polymerised acrylic material and / or an emulsion polymerised acrylic material. As used herein, “solution polymerised” means a polymer that is formed by a polymerisation method whereby a monomer is substantially dissolved in a solvent and polymerised. Once said monomer has been polymerised, the resultant solution polymerised acrylic material is suitably substantially soluble in said solvent.

[0043]

[0041] The acrylic material may be formed by a solution polymerisation method. Suitable solution polymerisation methods will be well to a person skilled in the art. The solution polymerisation method comprises a plurality of components, which may be referred to as a solution polymerisation reaction mixture.

[0044]

[0042] The solution polymerisation reaction mixture may comprise a monomer component. The monomer component may comprise one or more acrylic monomer(s) as described above. The monomer component may optionally comprise one or more additional ethylenically unsaturated monomer(s) as described above.

[0045]

[0043] The solution polymerisation reaction mixture may further comprise an initiator. The initiator may be a free radical initiator. Examples of suitable initiators include, but are not limited to, tertiary butyl perbenzoate; tert butyl peroxy 3,5,5 trimethylhexanoate; tertiary butyl peroxy 2- ethyl hexanoate; T-amyl peroxy 2-ethyl hexanoate; di tertiary butyl peroxide; tertiary butyl peracetate; tertiary butyl peroctoate; azo type initiators such as, for example, 2,2’- azobis(isobutyronitrile), 2,2'-Azobis(2-methylbutyronitrile), 2,2'-Azobis(2.4-dimethyl valeronitrile) and 2,2'-Azobis(4-methoxy-2.4-dimethyl valeronitrile); persulphate initiators such as, for example, ammonium persulphate, sodium persulphate or potassium persulphate; and combinations thereof. The initiator may comprise 2,2'-Azobis(2-methylbutyronitrile). The initiator may be soluble in the solution polymerisation reaction mixture. The initiator may be soluble in the monomer component.

[0046]

[0044] The solution polymerisation reaction mixture may comprise a solvent or mixture of solvents. Suitable solvents will be well known to a person skilled in the art. Examples of suitable solvents include, but are not limited to, aliphatic hydrocarbons such as mineral spirits and high flash point naphtha; 2,2-dimethoxypropane (DMP); Rhodiasolv (RTM) RPDE commercially available from Solvay; methyl ethyl ketone; methyl isobutyl ketone; cyclohexanone; aromatic hydrocarbons such as benzene; toluene; xylene; solvent naphtha 100, 150, 150ND, 200 and / or 200ND; those sold under the tradename SOLVESSO (RTM) commercially available from Exxon-Mobil Chemical Company; alcohols such as, for example, propanol, isopropanol, n- butanol, pentanol, hexanol or diacetone alcohol; glycols such as, for example, butyl glycol; glycol ethers such as, for example, 2-butoxy ethanol, 1 -methoxy propan-2-ol; esters such as, for example, ethyl acetate, butyl acetate, n-hexyl acetate, dibasic ester commercially available from Sigma Aldrich, propylene glycol methyl ether acetate, butyl glycol acetate and butyl diglycol acetate; glycols such as butyl glycol and dibutyl glycol; glycol ethers such as methoxypropanol, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, propylene glycol methyl ether and dipropylene glycol mono methyl ether; and combinations thereof. The solvent may comprise a mixture of solvents, such as n-butanol and butyl glycol, for example. It will be appreciated by a person skilled in the art that the solvent or mixture of solvents may be chosen such that the monomer component is substantially soluble in said solvent or mixture of solvents.

[0047]

[0045] The solution polymerisation reaction mixture may be substantially free, may be essentially free or may be completely free of alcohol solvents. By “substantially free” we mean to refer to reaction mixtures comprising less than 10 vol% alcohol solvents based on the total volume of solvent present. By “essentially free” we mean to refer to reaction mixtures comprising less than 5 vol% alcohol solvents based on the total volume of solvent present. By “completely free” we mean to refer to reaction mixtures comprising less than 1 vol% alcohol solvents based on the total volume of solvent present. The solution polymerisation reaction mixture may comprise 0 vol% alcohol solvent based on the total volume of solvent present. By using 0 wt% alcohol solvent in the solution polymerisation reaction mixture, the initiation of lactone and / or lactide polymerisation may be reduced or eliminated.

[0048]

[0046] The monomer component is caused to undergo polymerisation in the solvent or mixture of solvents to form the acrylic material. The solution polymerisation of the monomer component may be carried out as a free radical initiated solution polymerisation in a solvent or mixture of solvents.

[0047] Solution polymerisation may be carried out in a suitable reaction vessel. The monomer component, initiator and / or solvent or mixture of solvents may be added to the reaction vessel in any suitable order. For example, the solvent or mixture of solvents may be added to the reaction vessel before the monomer component and / or initiator are added to the reaction vessel. The monomer component and initiator may be added to the reaction vessel at the same time. The monomer component and / or initiator may be added to the reaction vessel over any suitable period of time. The monomer component and / or initiator may be added to the reaction vessel over a time period of 0 to 12 hours, such as 30 minutes to 8 hours, such as 1 hour to 6 hours, or even 2 hours to 4 hours. For the avoidance of doubt, when the monomer component and / or initiator are added over a time period of 0 hours, all of the monomer component and / or initiator are added at the same time (i.e. in one single addition).

[0049]

[0048] Solution polymerisation may be carried out at any suitable temperature. Solution polymerisation may be carried out at an elevated temperature. Solution polymerisation may be carried out at a temperature from 80°C to 200°C, such as from 80°C to 180°C, such as from 80°C to 160°C, such as from 80°C to 150°C, such as from 80°C to 140°C, such as from 80°C to 130°C, such as from 80°C to 120°C, such as 80°C to 110°C, or even from 90°C to 110°C. Solution polymerisation may be carried out at a temperature from 90°C to 110°C. Solution polymerisation may be carried out at reflux. Solution polymerisation may be carried out at a temperature of 80°C or above, such as 100°C or above, such as 120°C or above, such as 130°C or above, or even 135°C or above. Solution polymerisation may be carried out at a temperature of 250°C or below, such as 200°C or below, such as 180°C or below, such as 160°C or lower, such as 150°C or lower, or even 145°C or lower.

[0050]

[0049] The acrylic material may be prepared by emulsion polymerisation. Suitable emulsion polymerisation methods will be well known to a person skilled in the art. The emulsion polymerisation method may comprise a plurality of components, which may be referred to as an emulsion polymerisation reaction mixture.

[0051]

[0050] The emulsion polymerisation reaction mixture may comprise an emulsion polymerisation monomer component. The emulsion polymerisation monomer component comprises one or more acrylic monomer(s) as described above. The emulsion polymerisation monomer component may optionally comprise additional ethylenically unsaturated monomer(s) as described above.

[0052]

[0051] The emulsion polymerisation reaction mixture may further comprise an initiator. Suitable initiators are as described above (in relation to solution polymerisation methods).

[0053]

[0052] The emulsion polymerisation reaction mixture comprises water.

[0054]

[0053] The monomer component of the emulsion polymerisation reaction mixture may be caused to undergo polymerisation in the water to form the acrylic polymer particles. Thus, the polymerisation of the monomer component of the emulsion polymerisation reaction mixture is typically carried out as a free radical initiated emulsion polymerisation in water. The monomer component of the emulsion polymerisation reaction mixture may form an oil phase in the water.

[0054] The emulsion polymerisation reaction mixture may comprise a buffer. Suitable buffers will be well known to a person skilled in the art. The buffer may be operable to act as a hydrogen ion acceptor. Examples of suitable buffers include, but are not limited to, sodium bicarbonate.

[0055]

[0055] The emulsion polymerisation reaction mixture may comprise a surfactant. The surfactant may be an anionic, cationic or non-ionic type stabilizer. Suitable examples of anionic surfactants include, but are not limited to, alkyl sulphates such as, for example, sodium dodecyl sulphate or sodium polyoxy ethylene alkyl ether sulphate; aryl sulphonates such as, for example, sodium dodecylbenzene sulphonate; sulphosuccinates such as, for example, sodium diisobutyl sulpho succinate, sodium dioctyl sulpho succinate and sodium di cyclohexyl sulpho succinate; and combinations thereof. Suitable examples of nonionic emulsifiers include, but are not limited to, fatty alcohol ethoxylates such as, for example polyethylene glycol mono lauryl ether; fatty acid ethoxylates such as, for example, polyethylene glycol mono stearate or polyethylene glycol mono laurate; polyether block polymers such as, for example, polyethylene glycol / polypropylene glycol block polymers also known as pluronics, typical commercial products of this type include Tergitol XJ, XH or XD commercially available from Dow Chemical; and combinations thereof. Suitable examples of cationic emulsifiers include, but are not limited to, amine salts such as, for example, cetyl trimethyl ammonium chloride or benzyl dodecyl dimethyl ammonium bromide; and combinations thereof. It will be appreciated by a person skilled in the art that mixtures of anionic and cationic emulsifiers would typically not be desirable.

[0056]

[0056] However, the emulsion polymerisation reaction mixture may be substantially free, may be essentially free or may be completely free of surfactant. By substantially free in relation to surfactants, is meant that the emulsion polymerisation reaction mixture comprises less than 5 wt% of surfactant based on the total weight of the emulsion polymerisation reaction mixture. By essentially free in relation to surfactants, is meant that the emulsion polymerisation reaction mixture comprises less than 1 wt% of surfactant based on the total weight of the emulsion polymerisation reaction mixture. By completely free in relation to surfactants, is meant that the emulsion polymerisation reaction mixture comprises less than 0.01 wt% of surfactant based on the total weight of the emulsion polymerisation reaction mixture. The emulsion polymerisation reaction mixture may comprise no, i.e. 0 wt%, surfactant.

[0057]

[0057] The surfactant may be polymeric. The surfactant may be polymerisable with the emulsion polymerised acrylic latex material. For example, the surfactant may be polymerisable with the monomers that form the oxirane-functional acrylic polymer particles.

[0058]

[0058] The emulsion polymerisation reaction mixture may comprise a neutraliser. Suitable neutralisers are as described above (in relation to solution polymerisation methods). A neutraliser may be added to at least of portion of the emulsion polymerisation monomer component. A neutraliser may be added to at least a portion of the emulsion polymerisation monomer component prior to the polymerisation reaction, i.e. prior to the emulsion polymerisation monomer component contacting the initiator.

[0059] Advantageously, when the oxirane-functional acrylic polymer particles are formed by an emulsion polymerisation method, the oxirane-functional acrylic polymer particles may be prepared in the absence of surfactants.

[0059]

[0060] Emulsion polymerisation is typically carried out in a suitable reaction vessel. The emulsion polymerisation monomer component, initiator and / or water of the emulsion polymerisation reaction mixture may be added to the reaction vessel in any suitable order. For example, the water may be added to the reaction vessel before the emulsion polymerisation monomer component and / or initiator are added to the reaction vessel. The initiator may be added to the reaction vessel before the emulsion polymerisation monomer component. The emulsion polymerisation monomer component and / or initiator may be added to the reaction vessel over any suitable period of time. The emulsion polymerisation monomer component and / or initiator may be added to the reaction vessel over a time period of from 0 to 24 hours, such as from 30 minutes to 12 hours, such as from 1 hour to 10 hours, such as from 2 hours to 10 hours, or even from 2 to 6 hours. For the avoidance of doubt, when the emulsion polymerisation monomer component and / or initiator are added over a time period of 0 hours, all of the emulsion polymerisation monomer component and / or initiator are added at the same time (i.e. in a single addition).

[0060]

[0061] The emulsion polymerisation monomer component may be added at any suitable rate during the time period for addition of the emulsion polymerisation monomer component. The emulsion polymerisation monomer component may be added at a constant rate or the emulsion polymerisation monomer component may be added at a variable rate during the time period for addition of the emulsion polymerisation monomer component. The emulsion polymerisation monomer component may be added dropwise. By the term ‘dropwise’ and like terms as used herein is meant, unless specified otherwise, that the emulsion polymerisation monomer component is added at a rate of from 0.05 to 1.0 wt% / minute over a period of time, T, based on the total solid weight of the monomers in the emulsion polymerisation monomer component. The emulsion polymerisation monomer component may be added at a rate which results in a low level of free monomer in the emulsion polymerisation reaction mixture. The emulsion polymerisation monomer component may be added at a rate which reduces or substantially prevents the monomers of the emulsion polymerisation monomer component from being insoluble in the emulsion polymerisation reaction mixture. In other words, the emulsion polymerisation monomer component may be added at a suitable rate such that the monomers of the emulsion polymerisation monomer component are and / or remain substantially dissolved in the emulsion polymerisation reaction mixture.

[0061]

[0062] The monomer component may be added at a variable rate during the time period for addition of the monomer component. The monomer component may be added at a slower rate initially and then at an increasingly faster rate during the time period for addition of the monomer component.

[0063] Emulsion polymerisation may be carried out at any suitable temperature. Emulsion polymerisation may be carried out at a temperature from 20°C to 150°C, such as from 40°C to 120°C, such as from 50°C to 100°C, such as from 60°C to 95°C, or even from 70°C to 90°C. Emulsion polymerisation may be carried out at a temperature of 80°C. The temperature is typically held constant throughout the emulsion polymerisation process.

[0062]

[0064] The oxirane-functional acrylic polymer particles may be in a core / shell arrangement.

[0063]

[0065] The shell may be formed from a plurality of components, which may be referred to as a shell mixture. The shell mixture comprises one or more acrylic monomer(s) as described above. The emulsion polymerisation reaction mixture may optionally comprise one or more additional ethylenically unsaturated monomer(s) as described above.

[0064]

[0066] The shell mixture may further comprise one or more initiator(s). Suitable initiators are as described above in relation to the acrylic material.

[0065]

[0067] The shell mixture may be caused to undergo polymerisation to form a shell polymer. The polymerisation of the shell mixture may typically be carried out as a free radical initiated solution polymerisation in a solvent or mixture of solvents. The solvents which may be used in this process include, but are not limited to, alcohols such as n- butanol, pentanol or hexanol; or glycol ethers such as 2-butoxy ethanol, 1 -methoxy propan-2-ol or dipropylene glycol mono methyl ether. Polymerisation may be carried out at an elevated temperature. Typically, the polymerisation may be carried out in the range 80°C to 150°C. The polymerisation can be effectively carried out by adding the shell mixture, over a set time period, to the solvent mixture. The shell mixture may be caused to undergo polymerisation to form a shell polymer prior to contact with components of the core mixture.

[0066]

[0068] Where the shell mixture comprises one or more a,p-ethylenically unsaturated carboxylic acid(s), the shell polymer will have pendant carboxylic acid functional groups. This may be referred to a carboxylic acid functional shell polymer.

[0067]

[0069] The carboxylic acid functional shell polymer may be contacted with a base to form a water dispersible salt. The carboxylic acid functionality in the carboxylic acid functional shell polymer may be at least partly neutralised with the base. Typically, at least 10% of the available carboxylic acid groups are neutralised. Substantially all of the available carboxylic acid groups may be neutralised by the base. The base used for this neutralisation may comprise an amine functional material, or a mixture of amine functional materials. Examples of suitable amine functional materials include, but are not limited to, ammonia, triethylamine, diethylamine, trimethylamine and morphline or hydroxy amine materials such as ethanol amine, N-methyl ethanol amine and N,N-di methyl ethanolamine.

[0068]

[0070] The shell polymer may be dispersed in aqueous medium. In this manner, an aqueous dispersion or solution of the shell polymer may be formed.

[0069]

[0071] The shell mixture may be caused to undergo polymerisation to form a shell polymer by emulsion polymerisation in an aqueous medium, thereby forming an aqueous dispersion or solution of the shell polymer.

[0072] The core may be formed from plurality of components, which may be referred to as a core mixture. The core mixture may comprise one or more acrylic monomer(s) as described above. The emulsion polymerisation reaction mixture may optionally comprise one or more additional ethylenically unsaturated monomer(s) as described above.

[0070]

[0073] The polymer formed from the shell mixture, such as an aqueous dispersion thereof, may serve as a dispersant for a subsequent polymerisation, which may be a polymerisation of an a,p-ethylenically unsaturated monomer mixture, such as the core mixture.

[0071]

[0074] The core mixture may further comprise one or more one or more initiator(s). Suitable initiators are as described above (in relation to solution polymerisation methods).

[0072]

[0075] The core mixture may be caused to undergo polymerisation at a temperature in the range from 30°C to 99°C, such as in the range from 50°C to 95°C, such as in the range from 80°C to 90°C. Polymerisation of the core mixture may occur in the presence of the polymer formed by polymerisation of the shell mixture to thereby form a core / shell polymer, typically by emulsion polymerisation. A typical polymerisation may be carried out by adding the core mixture, at a controlled rate over a period of time, to an aqueous dispersion of shell polymer. During the polymerisation the mixture may be mixed, such as by stirring and the temperature may be held generally constant.

[0073]

[0076] Other methods to polymerise the core mixture include, but are not limited to, mixing all or part of the core ethylenically unsaturated substances with the aqueous dispersion of shell polymer and then adding the remaining core components, including initiator, to the resulting mixture over a set period of time. Suitable temperatures for this type of process are typically in the range 50°C to 95°C.

[0074]

[0077] For the core / shell latex composition the ratio of the core mixture (monomers and initiator) to shell mixture (monomers and initiator) may be from 20:80 to 90:10 by weight. The ratio of the core mixture to shell mixture may be from 60:40 to 80:20 by weight, the ratio of the core mixture to shell mixture components may be from 70:30 to 75:25.

[0075]

[0078] The post repair coating composition may comprise any suitable amount of the acrylic material. The post repair coating composition may comprise at least 50 wt%, such as at least 60 wt%, such as at least 70 wt%, such as at least 75 wt%, such at least 80 wt% of the acrylic material based on the total solid weight of the composition.

[0076]

[0079] The post repair coating composition may comprise up to 99.9 wt%, suitably up to 99 wt%, such as up to 98 wt%, such as up to 97 wt%, such as up to 96 wt%, such as up to 95 wt%, such as up to 92 wt%, such as up to 90 wt% of the acrylic material based on the total solid weight of the composition.

[0077]

[0080] The post repair coating composition may comprise from 50 to 99.9 wt%, such as from 70 to 99.9 wt%, such as from 75 to 99.9 wt%, such as from 80 to 99.9 wt%, such as from 85 to 99.9 wt%, such as from 90 to 99.9 wt% of the acrylic material based on the total solid weight of the composition. The post repair coating composition may comprise from 50, 60, 70, 75 or 80 wt% to 99.9 wt% of the acrylic material based on the total solid weight of the composition, such as from 50, 60, 70, 75 or 80 wt% to 99 wt% of the acrylic material based on the total solid weight of the composition, such as from 50, 60, 70, 75 or 80 wt% to 98 wt% of the acrylic material based on the total solid weight of the composition, such as from 50, 60, 70, 75 or 80 wt% to 97 wt% of the acrylic material based on the total solid weight of the composition, such as from 50, 60, 70, 75 or 80 wt% to 96 wt% of the acrylic material based on the total solid weight of the composition, such as from 50, 60, 70, 75 or 80 wt% to 95 wt% of the acrylic material based on the total solid weight of the composition, such as from 50, 60, 70, 75 or 80 wt% to 92 wt% of the acrylic material based on the total solid weight of the composition, such as from 50, 60, 70, 75 or 80 wt% to 90 wt% of the acrylic material based on the total solid weight of the composition.

[0078]

[0081] The acrylic material may have any suitable glass transition temperature (Tg).

[0079]

[0082] The acrylic material may have a Tg of at least -10°C, such as at least 0°C, such as at least 10°C, such as at least 20°C, such as at least 25°C. The acrylic material may have a Tg up to 100°C, such as up to 90°C, such as up to 80°C, such as up to 70°C, such as up to 60°C, such as up to 50°C. The acrylic material may have a Tg from -10 to 100°C, such as from 0 to 100°C, such as from 10 to 100°C, such as from 20 to 100°C, such as from 25 to 100°C. The acrylic material may have a Tg from -10 to 90°C, such as from 0 to 90°C, such as from 10 to 90°C, such as from 20 to 90°C, such as from 25 to 90°C. The acrylic material may have a Tg from -10 to 80°C, such as from 0 to 80°C, such as from 10 to 80°C, such as from 20 to 80°C, such as from 25 to 80°C. The acrylic material may have a Tg from -10 to 70°C, such as from 0 to 70°C, such as from 10 to 70°C, such as from 20 to 70°C, such as from 25 to 70°C. The acrylic material may have a Tg from -10 to 60°C, such as from 0 to 60°C, such as from 10 to 60°C, such as from 20 to 60°C, such as from 25 to 60°C. The acrylic material may have a Tg from -10 to 50°C, such as from 0 to 50°C, such as from 10 to 50°C, such as from 20 to 50°C, such as from 25 to 60°C. The acrylic material may have a Tg from -10 to 100°C, such as from 0 to 80°C, such as from 0 to 60°C, such as from 0 to 50°C, such as from 10 to 50°C, such as from 20 to 50°C.

[0080]

[0083] The acrylic material may have a Tg of at least 25°C.

[0081]

[0084] The acrylic material may have a Tg from 25 to 60°C.

[0082]

[0085] As reported herein, the Tg was calculated according to the Fox equation:

[0083] 1 / Tg = Wfi / Tgi + Wf2 / Tg2+ ... WfN / TgNwhere 1 , 2, ... N represent the individual monomers from which the polymer is made; Wfi, Wf2, ... WfN represent the weight fraction of monomers 1 , 2, ... N (wherein Wfi, Wf2, ... W(N add up to 1); and Tgi, Tg2, ... TgN represent the glass transition temperatures in degrees Kelvin for the homopolymers of each of monomers 1 , 2, ... N. The Tg is calculated in degrees Kelvin and converted to degrees Celsius (°C), i.e., Tg(°C) = Tg(K) - 273.

[0084]

[0086] All values for Tg reported herein were calculated in this way unless specified otherwise.

[0085]

[0087] The acrylic material may have any suitable epoxy equivalent weight (EEW) on solution. The acrylic material may have an epoxy equivalent weight on solution of at least 100, such as at least 200, such as at least 300, such as at least 400, such as at least 500, such as at least 600, such as at least 700, such as at least 800, such as at least 825, such as at least 850, such as at least 900, such as at least 950, such as at least 1 ,000, such as at least 1 ,100, such as at least 1,200, such as at least 1 ,300, such as at least 1 ,400, such as at least 1 ,500.

[0086]

[0088] The acrylic material may have an EEW on solution of at least 800.

[0087]

[0089] The acrylic material may have an EEW on solution of at least 825.

[0088]

[0090] The acrylic material may have an EEW on solution up to 3,000, such as up to 2,500, such as up to 2,400, such as up to 2,300, such as up to 2,200, such as up to 2,100, such as up to

[0089] 2,000, such as up to 1,900, such as up to 1,800.

[0090]

[0091] The acrylic material may have an EEW on solution from 800 to 2,000.

[0091]

[0092] The acrylic material may have an EEW on solution from 800 to 1,800.

[0092]

[0093] The acrylic material may have an EEW on solution from 825 to 2,000.

[0093]

[0094] The acrylic material may have an EEW on solution from 825 to 1,800.

[0094]

[0095] The acrylic material may have an EEW on solution from 850 to 2,000.

[0095]

[0096] The acrylic material may have an EEW on solution from 850 to 1,800.

[0096]

[0097] The epoxy equivalent weight (EEW) is defined as the mass of resin (in grams) containing 1 mole of epoxy groups. All values for EEW provided herein are expressed on solution unless specified otherwise. As reported herein, the EEW on solution was determined potentiometrically by reaction with hydrobromic acid according to ASTM D1652-11 (2019) ("Standard test method for epoxy content of epoxy resins”; epoxy reagent: 10% w / v solution of tetraethylammonium bromide in glacial acetic acid; solvent blank, Vs: 30 mL glacial acetic acid and 20 mL methylene chloride titrated potentiometrically with 0.1 N perchloric acid, wherein the volume of the titrant consumed in mLs = Vs; epoxy reagent and solvent blank, Vb: 10 ml epoxy reagent, 30 mL glacial acetic acid and 20 mL methylene chloride titrated potentiometrically with 0.1 N perchloric acid, wherein the volume of titrant consumed in mLs = Vb; epoxy reagent blank, Vr: Vb - Vs; sample weight: epoxy theory / 1667; test solution Vt: sample, 30 mL glacial acetic acid, 10 mL epoxy reagent titrated potentiometrically with 0.1 N perchloric acid, wherein the volume of of titrant consumed in mLs = Vt; EEW = (sample weight‘1000) / ([Vt - Vr] * 0.1)), wherein 0.1 is the normality of perchloric acid). All values for EEW reported herein were measured in this way unless specified otherwise.

[0097]

[0098] It will be appreciated by a person skilled in the art that the epoxy equivalent weight (EEW) may alternatively be expressed on solids. The acrylic material may have any suitable epoxy equivalent weight (EEW) on solids, for example the acrylic material may have an epoxy equivalent weight on solids of at least 50, such as at least 100, such as at least 150, such as at least 200, such as at least 250, such as at least 300, such as at least 350, such as at least 400, such as at least 425, such as at least 450, such as at least 475, such as at least 500, such as at least 550, such as at least 600, such as at least 650, such as at least 700, such as at least 750.

[0099] The acrylic material may have an EEW on solids up to 1 ,500, such as up to 1 ,250, such as up to 1 ,200, such as up to 1 ,150, such as up to 1 ,100, such as up to 1 ,050, such as up to 1,000, such as up to 950, such as up to 900.

[0098]

[0100] The acrylic material may have an EEW on solids from 400 to 1 ,000.

[0099]

[0101] The acrylic material may have an EEW on solids from 400 to 900.

[0100]

[0102] The acrylic material may have an EEW on solution from 425 to 1,000

[0101]

[0103] The acrylic material may have an EEW on solution from 425 to 900.

[0102]

[0104] The acrylic material may have any suitable number average molecular weight (Mn). The acrylic material may have an Mn of at least 500 Daltons (Da = g / mole), such as at least 1,000 Da, such as at least 2,000 Da, such as at least 3,000 Da, such as at least 4,000 Da, such as at least 5,000 Da, such as at least 6,000 Da, such as at least 7,000 Da, such as at least 8,000 Da, such as at least 9,000 Da. The acrylic material may have an Mn up to 250,000 Da, such as up to 200,000 Da, such as up to 150,000 Da, such as up to 100,000 Da, such as up to 50,000 Da, such as up to 25,000 Da, such as up to 20,000 Da, such as up to 15,000 Da. The acrylic material may have an Mn from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000 or 9,000 to 250,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000 or 9,000 to 200,000 Da, such as from 500, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000 or 9,000 to 150,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000 or 9,000 to 100,000 Da, such as from 500, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000 or 9,000 to 50,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000,

[0103] 6,000, 7,000, 8,000 or 9,000 to 40,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000,

[0104] 6,000, 7,000, 8,000 or 9,000 to 30,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000,

[0105] 6,000, 7,000, 8,000 or 9,000 to 25,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000,

[0106] 6,000, 7,000, 8,000 or 9,000 to 20,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000,

[0107] 6,000, 7,000, 8,000 or 9,000 to 15,000 Da.

[0108]

[0105] The acrylic material may have an Mn from 8,000 Da.

[0109]

[0106] The acrylic material may have an Mn from 9,000 to 15,000 Da.

[0110]

[0107] The acrylic material may have an Mn from 8,000 to 15,000 Da.

[0111]

[0108] The acrylic material may have an Mn from 9,000 to 15,000 Da.

[0112]

[0109] As reported herein, the Mn was determined by gel permeation chromatography using a polystyrene standard according to ASTM D6579-11 (“Standard Practice for Molecular Weight Averages and Molecular Weight Distribution of Hydrocarbon, Rosin and Terpene Resins by Size Exclusion Chromatography”. Rl detector, solvent: unstabilised THF, retention time marker: toluene, sample concentration: 10mg / ml). All values for Mn reported herein were measured in this way unless specified otherwise.

[0113]

[0110] The acrylic material may have any suitable weight-average molecular weight (Mw).

[0114]

[0111] The acrylic material may have an Mw of at least 500 Daltons (Da = g / mole), such as at least 1 ,000 Da, such as at least 2,000 Da, such as at least 3,000 Da, such as at least 4,000 Da, such as at least 5,000 Da, such as at least 6,000 Da, such as at least 7,000 Da, such as at least 8,000 Da, such as at least 9,000 Da, such as at least 10,000 Da, such as at least 15,000 Da, such as at least 20,000 Da. The acrylic material may have an Mw up to 250,000 Da, such as up to 200,000 Da, such as up to 150,000 Da, such as up to 100,000 Da, such as up to 50,000 Da, such as up to 40,000 Da, such as up to 35,000 Da. The acrylic material may have an Mw from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 250,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 200,000 Da, such as from 500, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 150,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 100,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 50,000 Da, such as from 500, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 40,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 30,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 40,000 Da, such as from 500, 1 ,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 15,000 or 20,000 to 35,000 Da.

[0115]

[0112] The acrylic material may have an Mw from 15,000 to 35,000 Da.

[0116]

[0113] The acrylic material may have an Mw from 20,000 to 35,000 Da.

[0117]

[0114] As reported herein, the Mw was determined by gel permeation chromatography using a polystyrene standard according to ASTM D6579-11 (“Standard Practice for Molecular Weight Averages and Molecular Weight Distribution of Hydrocarbon, Rosin and Terpene Resins by Size Exclusion Chromatography”. Rl detector, solvent: unstabilised THF, retention time marker: toluene, sample concentration: 10 mg / ml).

[0118]

[0115] All values for Mw reported herein were measured in this way.

[0119]

[0116] The acrylic material may have any suitable polydispersity index (PDI), i.e. the ratio of Mw / Mn. The acrylic material may have a polydispersity index of up to 10, such as up to 9, such as up to 8, such as up to 7, such as up to 6, such as up to 5, such as up to 4, such as up to 3, such as up to 2.

[0120]

[0117] A person skilled in the art will appreciate that techniques to measure the number-average molecular weight may also be applied to measure the weight-average molecular weight.

[0121]

[0118] The acrylic material may have any suitable acid value (AV).

[0122]

[0119] The acrylic material may have pendant hydroxyl groups such that it is hydroxy-functional. For example, the acrylic material may be formed from a reaction mixture comprising one or more hydroxy-functional monomer(s). For example, the acrylic material may be formed from a reaction mixture comprising up to 20 wt%, such as up to 15 wt%, such as up to 10 wt%, such as up to 9, 8, 7, 6, 5, 4, 3, 2 or 1 w% hydroxy-functional monomer(s) based on the total weight of monomers present. Alternatively or additionally, hydroxy groups may be provided by the ring opening of oxirane groups.

[0120] The post repair coating composition of the present invention comprises a polyamine material. The post repair coating composition of the present invention may comprise any suitable polyamine material. The polyamine material may be an aliphatic, cycloaliphatic or aromatic compound containing two or more amine groups. The amine groups may be primary amine groups, secondary amine groups and / or tertiary amine groups.

[0123]

[0121] The amine groups may be present in a polymer backbone of the polyamine material, and / or may be present as an end group of the polyamine material, and / or may be present as a side group of the polyamine material.

[0124]

[0122] The polyamine material may comprise two or more primary amine groups.

[0125]

[0123] The polyamine material may comprise an aliphatic, cycloaliphatic and / or aromatic polyamine having two or more primary amine groups.

[0126]

[0124] The polyamine material may comprise an aliphatic, cycloaliphatic and / or aromatic polyamine having at least one secondary and / or tertiary amine group and at least two primary amine groups.

[0127]

[0125] The polyamine may be of the formula NHR1-[-X-NR2-]-X-NHR3, wherein each X is independently a bivalent organic bridging group, such as an alkylene, alkenylene, alkynylene, and / or arylene group, and R1, R2and R3each independently represent hydrogen, an alkyl group, an alkenyl group, an alkynyl group or an aromatic group. X may be unsubstituted or may be substituted by one or more heteroatom(s), such as by one or more oxygen atom(s). For example, X may be -(CHz)m-, wherein m is at least 1 , such as from 1 to 20, such as from 1 to 10, such as from 1 to 6, such as from 1 to 4. For example, X may be -O-(Ch2)n-, wherein n is at least 1 , such as from 1 to 20, such as from 1 to 10, such as from 1 to 6, such as from 1 to 4.

[0128]

[0126] The polyamine material further comprises at least one amide group, such as at least one secondary and / or tertiary amide group.

[0129]

[0127] Examples of suitable polyamines include, but are not limited to, polyetheramines, such as poly(ethylene glycol) diamine and triethylene glycol diamine, for example, ethylene diamine, 1,2- propane diamine, 1 ,3-propane diamine, tetramethylene diamine, 1 ,6-hexane diamine, trimethyl hexane-1,6-diamine, isophrone diamine, diaminodiphenylmethane (methylene dianaline), diaminodiphenylether, diaminodiphenylsulphone, 4,4-diaminodicyclohexylmethane, 4,4-diamino- 3,3-dimethyldicyclohexylmethane, polyoxypropylene triamine (for example having an average molecular weight Mw of 400 to 450), polyoxyethylene triamine (for example having an average molecular weight Mw of 400 to 450), benzoguanamine, ortho-xylylene diamine, meta-xylylene diamine, para-xylylenediamine, 1 ,2-cyclohexanediamine, 1 ,4-cyclohexanediamine, polyaminoamides, and combinations thereof.

[0130]

[0128] The polyamine material may comprise the reaction product of an epoxidized polyolefin and a polyamide. Examples of suitable polyamides include, but are not limited to, condensation products of polyamines, such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine and those illustrated by the formula H(HNR)nNH2 where R is an alkylene radical having from 2 to 6 carbon atoms and n is an integer of 1 to 6, and oligomeric fatty acids. Examples of suitable oligomeric fatty acids include, but are not limited to, those resulting from the polymerization of drying or semi-drying oils or their free acids, or the simple aliphatic alcohol esters of these acids, such as from sources rich in linoleic acid. Examples of suitable simple drying or semi-drying oils include, but are not limited to, soybean, linseed, tung, perilla, cottonseed, corn, sunflower, safflower and dehydrated castor oils. Examples of suitable fatty acids may also be obtained from tall oil, soap stock and other similar materials. In the process for the preparation of the oligomeric fatty acid, the fatty acids with sufficient double bond functionality combine to provide a mixture of dibasic and oligomeric fatty acids. These acids are referred to as dimers, trimers and the like. The term "oligomeric fatty acids" as used herein, is intended to include any individual oligomeric fatty acid as well as mixtures of oligomeric fatty acids, the latter typically containing a predominant portion of dimer acids, a small quantity of trimer and higher polymeric fatty acids and some residual monomer. The oligomeric fatty acids containing predominantly the dimeric form of the acid with some residual monomer and small quantities of trimer and higher polymeric fatty acid, may be hydrogenated, if desired, and the hydrogenated product employed to form the polyamide. In addition, the polymeric fatty acids may be distilled to provide relatively high dimer content acids.

[0131]

[0129] The polyamine and the oligomeric fatty acid may be condensed at elevated temperatures to form the polyamide. An excess of polyamine is typically used to get an amine-functional, such as amine terminated, polyamide. By excess is meant the ratio of equivalents of amine to equivalents of carboxyl is greater than 1. The reaction product may have an amine number in the range of 50 to 80.

[0132]

[0130] Examples of suitable epoxidized polyolefin include, but are not limited to, epoxidized polybutadiene; epoxidized polyisoprene; an epoxidized copolymer of a diolefin, such as a copolymer with styrene; olefins based on fatty acids, including condensates thereof with various alcohols such as glycerol. The epoxidized polyolefin may comprise epoxidized polybutadiene, for example those characterized by a substantially linear structure having an epoxy oxygen content of 5 to 10 percent by weight, an epoxy equivalent weight of 300 to 3,000, and a hydroxyl group content of 1 to 3 percent by weight.

[0133]

[0131] It will be appreciated by a person skilled in the art that the epoxidized polyolefin should be substantially free of bisphenol A (BPA), bisphenol F (BPF) and derivatives thereof.

[0134]

[0132] The polyamine material may be commercially available. Examples of suitable commercially available polyamine materials include, but are not limited to, those sold under the trade name ARA (RTM) Cool commercially available from Huntsman Corporation, such as ARA Cool 3077, ARA Cool 1047 W80 and ARA Cool 1034 XW 90, those sold under the tradename VERSAMID (RTM) commercially available from Huntsman Corporation, such as VERSAMID 100, VERSAMID 115, VERSAMID 125 HV, VERSAMID 150, VERSAMID EH-30, VERSAMID F- 11 , VERSAMID 100 T-60, VERSAMID 125, VERSAMID 140, VERSAMID C-30 and VERSAMID EH-50, those sold under the trade name Jeffamine (RTM) commercially available from Huntsman Corporation, such as Jeffamine D-4000, Jeffamine D-2000, Jeffamine D-400, Jeffamine D230, Jeffamine HK-511 , Jeffamine ED-600, Jeffamine ED-900, Jeffamine ED-2003, Jeffamine EDR-148, Jeffamine EDR-176, Jeffamine T-403, Jeffamine T-3000 and Jeffamine T- 5000); and those sold under the trade name EPIKURE (RTM) commercially available from Westlake Epoxy, such as EPIKURE 3115, EPIKURE 115-E-73, EPIKURE 3115-X-70 and EPIKURE 3115-U-80.

[0135]

[0133] The polyamine material may be formed from reactants that are substantially free of silane. The polyamine material may be essentially free or may be completely free of silane. By “substantially free” we mean to refer to polyamine materials formed from reactants that contain 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 polyamine materials formed from reactants that contain less than 100 ppm of any of the compounds or derivatives thereof mentioned above. By “completely free” we mean to refer to polyamine materials formed from reactants that contain less than 20 parts per billion (ppb) of any of the compounds or derivatives thereof.

[0136]

[0134] The polyamine material may be formed from reactants that contain 0 wt% of silane. Thus, the polyamine material may be formed from reactants that do not include silane.

[0137]

[0135] The polyamine material may have any suitable amine value. The polyamine material may have an amine value of at least 200 mg KOH / g, such as at least 250 mg KOH / g, such as at least 300 mg KOH / g. As reported herein, the amine value may be measured according to ISO 9702:1996 (“Plastics - Amine epoxide hardeners - Determination of primary, secondary and tertiary amine group nitrogen content”).

[0138]

[0136] The post repair coating composition may comprise any suitable amount of the polyamine material. The post repair coating composition may comprise at least 1 wt%, such as at least 2 wt%, such as at least 3 wt%, such as at least 4 wt%, such as at least 5 wt%, such as at least 6 wt%, such as at least 7 wt%, such as at least 8 wt%, such as at least 9 wt%, such as at least 10 wt% of the polyamine material based on the total solid weight of the composition. The post repair coating composition may comprise up to 90 wt%, such as up to 80 wt%, such as up to 70 wt%, such as up to 50 wt%, such as up to 40 wt%, such as up to 30 wt%, such as up to 20 wt% of the polyamine material based on the total solid weight of the composition.

[0139]

[0137] The post repair coating composition may comprise from 1 , 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 90 wt% of the polyamine material based on the total solid weight of the composition, such as from 1 , 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 80 wt% of the polyamine material based on the total solid weight of the composition, such as from 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 70 wt% of the polyamine material based on the total solid weight of the composition, such as from 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 60 wt% of the polyamine material based on the total solid weight of the composition, such as from 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 50 wt% of the polyamine material based on the total solid weight of the composition, such as from 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 40 wt% of the polyamine material based on the total solid weight of the composition, such as from 1 , 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 30 wt% of the polyamine material based on the total solid weight of the composition, such as from 1 , 2, 3, 4, 5, 6, 7, 8, 9 or 10 wt% to 20 wt% of the polyamine material based on the total solid weight of the composition.

[0140]

[0138] The post repair coating composition may comprise from 2 to 20 wt% of the polyamine material based on the total solid weight of the composition.

[0141]

[0139] The post repair coating composition may comprise from 5 to 15 wt% of the polyamine material based on the total solid weight of the composition.

[0142]

[0140] The post repair coating composition may comprise any suitable weight ratio of acrylic material to polyamine material. The weight ratio of acrylic material to polyamine material may be from 20:1 to 1 :1, such as from 10:1 to 2:1 , such as from 10:1 to 5:1.

[0143]

[0141] The post repair coating composition may comprise any suitable weight ratio of acrylic material to polyamine material. The weight ratio of acrylic material to polyamine material may be at least 1 :1 , such as at least 2:1 , such as at least 3:1 , such as at least 4:1, such as at least 5:1, such as at least 6:1 , such as at least 8:1 , such as at least 9:1 , such as at least 10:1. The weight ratio of acrylic material to polyamine material may be from 50:1 to 1 :1 , such as from 50:1 to 2:1, such as from 50 to 5:1 , such as from 40:1 to 5:1, such as from 30:1 to 5:1 , such as from 25:1 to 5:1, such as from 20:1 to 5:1 , such as from 20:1 to 5:1, such as from 15:1 to 5:1 , such as from 10:1 to 5:1.

[0144]

[0142] The polyamine is operable to react with the oxirane-functionality on the acrylic material, such as upon cure, to form a crosslinked polymer network. The post repair coating composition may comprise a further crosslinker material. The post repair coating composition may comprise any suitable further crosslinker material. Suitable further crosslinker materials include, but are not limited to, the following: phenolic resins (or phenol-formaldehyde resins); aminoplast resins (or triazine-formaldehyde resins); amino resins; epoxy resins; epoxy-mimic resins, such as those based on bisphenols and other bisphenol A (BPA) replacements; isocyanate resins, isocyanurate resins, such as triglycidylisocyanurate; and combinations thereof.

[0145]

[0143] Non-limiting examples of phenolic resins are those formed from the reaction of a phenol with an aldehyde or a ketone, such as from the reaction of a phenol with an aldehyde, such as from the reaction of a phenol with formaldehyde or acetaldehyde, or even from the reaction of a phenol with formaldehyde. Non-limiting examples of phenols which may be used to form phenolic resins are phenol, butyl phenol, xylenol and cresol. General preparation of phenolic resins is described in “The Chemistry and Application of Phenolic Resins or Phenoplasts”, Vol V, Part I, edited by Dr Oldring; John Wiley and Sons / Cita Technology Limited, London, 1997. The phenolic resins are of the resol type. By “resol type” is meant resins formed in the presence of a basic (alkaline) catalyst and optionally an excess of formaldehyde. Examples of suitable commercially available phenolic resins include, but are not limited to, those sold under the trade name PHENODUR (RTM) commercially available from Cytec Industries, such as PHENODUR EK-827, PHENODUR VPR1785, PHENODUR PR 515, PHENODUR PR516, PHENODUR PR 517, PHENODUR PR 285, PHENODUR PR612, PHENODUR 520, PHENODUR 307 or PHENODUR PH2024; resins sold under the trade name BAKELITE (RTM) commercially available from Momentive, such as BAKELITE 6582 LB, BAKELITE 6535, BAKELITE PF9989, BAKELITE PF 7295 LB, BAKELITE 6736 LG, BAKELITE 6572 LB or BAKELITE PF6581 ; SFC 112 commercially available from Schenectady; DUREZ (RTM) 33356 commercially available from SHHPP; Curaphen 40-862 commercially available from Bitrez; BDP2220 / DF0181 commercially available from Bitrez; BURNOCK PH2891 commercially available from DIG Corporation; Askofen R9500 commercially available from Ask Chemicals; or combinations thereof.

[0146]

[0144] Non limiting examples of isocyanate resins include, but are not limited to, isophorone diisocyanate (I PDI) , such as those sold under the trade name DESMODUR (RTM) commercially available from Covestro, for example DESMODUR VP-LS 2078 / 2 or DESMODUR PL 340 or those sold under the trade name VESTANAT (RTM) commercially available from Evonik, for example VESTANANT B 1370, VESTANAT B 118 6A or VESTANAT B 1358 A; blocked aliphatic poly isocyan ate based on hexamethylene diisocyanate (H DI), such as those sold under the trade name DESMODUR (RTM) commercially available from Covestro, for example DESMODUR BL3370 or DESMODUR BL 3175 SN, those sold under the trade name DURANATE (RTM) commercially available from Asahi KASEI, for example DURANATE MF- K60X, those sold under the trade name TOLONATE (RTM) commercially available from Perstorp, for example TOLONATE D2 or those sold under the trade name TRIXENE (RTM) commercially available from Baxenden, for example TRIXENE-BI-7984 or TRIXENE 7981 ; or combinations thereof.

[0147]

[0145] Non-limiting examples of aminoplast resins include those which are formed from the reaction of a triazine such as melamine or benzoguanamine with formaldehyde. The resultant compounds may be etherified with an alcohol such as methanol, ethanol, butanol or combinations thereof. The preparation and use of aminoplast resins is described in “The Chemistry and Applications of Amino Crosslinking Agents or Aminoplast”, Vol V, Part II, page 21 ff., edited by Dr Oldring; John Wiley and Sons / Cita Technology Limited, London, 1998. Examples of suitable commercially available aminoplast resins include, but are not limited to, those sold under the tradename MAPRENAL (RTM) such as MAPRENAL MF980, MF 820 / 60IB or 821 / 84B commercially available from Prefere Resins and those sold under the tradename CYMEL (RTM) such as CYMEL 303, CYMEL 651 E and CYMEL 1128 commercially available from Allnex.

[0148]

[0146] The post repair coating composition may comprise a liquid carrier. The liquid carrier may comprise a solvent. The liquid carrier may comprise a single solvent or a mixture of solvents.

[0149]

[0147] The solvent suitably has sufficient volatility to essentially entirely evaporate from the coating composition during the curing process. As a non-limiting example, the curing process may be by heating to a peak metal temperature (PMT) of up to 150 °C.

[0150]

[0148] Suitable organic solvents include, but are not limited to the following: aliphatic hydrocarbons such as mineral spirits and high flash point naphtha; aromatic hydrocarbons such as benzene; toluene; xylene; solvent naphtha 100, 150, 200; those available from Exxon-Mobil Chemical Company under the SOLVESSO (RTM) trade name; alcohols such as ethanol; n- propanol; isopropanol; and n-butanol; ketones such as acetone; cyclohexanone; methylisobutyl ketone; methyl ethyl ketone; esters such as ethyl acetate; butyl acetate; n-hexyl acetate; RHODIASOLV (RTM) RPDE (a blend of succinic and adipic esters commercially available from Rhodia); glycols such as butyl glycol; glycol ethers such as methoxypropanol; ethylene glycol monomethyl ether; ethylene glycol monobutyl ether and combinations thereof.

[0151]

[0149] The liquid carrier may comprise any suitable amount of solvent. The liquid carrier may comprise any suitable amount of solvent. The liquid carrier may comprise 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%, such as at least 45 wt%, such as at least 50 wt%, 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 80 wt%, such as at least 90 wt%, such as at least 95 wt%, such as at least 99 wt% solvent based on the total weight of the liquid carrier. The remainder of the liquid carrier may typically be made up from water, for example. The liquid carrier may comprise 100 wt% solvent based on the total weight of the liquid carrier.

[0152]

[0150] The liquid carrier may be used in the post repair coating composition in amounts from 5 to 95 wt%, such as from 10 to 90 wt%, such as from 20 to 90 wt%, such as from 30 to 90 wt%, such as from 40 to 90 wt%, such as from 50 to 90 wt%, such as from 60 to 85 wt%, such as from 65 to 85 wt%, such as from 65 to 80 wt% based on the total weight of the coating composition.

[0153]

[0151] The post repair coating compositions may be substantially free of bisphenol A (BPA) and derivatives thereof. The post repair coating compositions may be essentially free or may be completely free of bisphenol A (BPA) and derivatives thereof. Derivatives of bisphenol A include, for example, bisphenol A diglycidyl ether (BADGE). The post repair coating compositions may also be substantially free of bisphenol F (BPF) and derivatives thereof. The post repair coating 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 post repair coating compositions may also be substantially free of bisphenol S (BPS) and derivatives thereof. The post repair coating 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.

[0152] The post repair coating 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.

[0154]

[0153] The post repair coating 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.

[0155]

[0154] The post repair coating 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.

[0156]

[0155] The post repair coating composition may comprise other optional materials well known in the art of formulating coatings, such as colorants, plasticizers, abrasion-resistant particles, antioxidants, hindered amine light stabilizers, UV light absorbers and stabilizers, surfactants, brighteners, defoamers, surface additives, flow control agents, thixotropic agents, fillers, reactive diluents, catalysts, grind vehicles, lubricants, waxes and other customary auxiliaries.

[0157]

[0156] The post repair coating composition may comprise a colorant (or pigment, which terms may be used interchangeably herein). The colorant may be any suitable colorant.

[0158]

[0157] 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 coating compositions 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 coating compositions of the present invention. 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. Examples for packaging coating compositions are those approved for food contact, such as 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, and those listed in Article 178.3297 of the Code of Federal Regulations, which is incorporated by reference herein.

[0159]

[0158] The colorant may comprise an anti-corrosion pigment.

[0160]

[0159] The post repair coating compositions may be provided in any suitable form. The post repair coating 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.

[0161]

[0160] The post repair coating composition may be a two component (“2K”) composition or a multi-component composition, such as a two component (“2K”) composition.

[0162]

[0161] Thus, the post repair coating composition may be provided as a two-component composition comprising a first component and a second component. The first component may comprise the acrylic material, a liquid carrier and optionally one or more ingredients selected from catalysts, pigments, fillers and other customary auxiliaries (such as any of those defined herein). The second component may comprise the polyamine material and a liquid carrier. For example, the second component may comprise a carbodiimide material and a liquid carrier.

[0163]

[0162] When the composition is provided as a multi-part composition, such as a two- component composition, the components, such as first component and second component, are suitably mixed prior to application to a substrate. The components, such as first component and second component, 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 a substrate. The components, such as first component and second component, may be mixed immediately prior to application to a substrate. The components, such as first component and second component, 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.

[0164]

[0163] For the avoidance of doubt, when the composition is provided as a multi-component composition, such as a two-component composition, suitable amounts of each material which may be present in the post repair coating composition as defined herein are based on the total composition, i.e., on the amounts present in the coating composition when the two (or more) components are combined to form one coating composition, unless specified otherwise.

[0165]

[0164] The post repair coating compositions may have any suitable solids content. “Solids content” of a composition as used herein is defined as the total weight of solid materials present in a composition over the total weight of the composition and is defined as a percentage (i.e., solid content = [total solid wt] / [total weight]*100) . The post repair coating composition may have a solids content suitable to allow the composition to be spray applied to a substrate, i.e., to be sprayable. For example, the post repair coating composition may have a solids content from 10 to 30 wt%, such as from 12 to 25 wt%, such as from 15 to 22 wt% based on the total weight the coating composition.

[0166]

[0165] The first component of the two-component system may comprise at least 80 wt%, such as at least 90 wt%, such as at least 95 wt%, such as at least 99 wt% of the acrylic material based on the total solid weight of the first component.

[0167]

[0166] The second component of the two-component system may comprise at least 80 wt%, such as at least 90 wt%, such as at least 95 wt%, such as at least 99 wt% of the polyamine material based on the total solid weight of the second component.

[0168]

[0167] The coating compositions may be applied to any suitable substrate. The substrate may be formed of metal.

[0169]

[0168] Suitable metals include, but are not limited to, the following: steel; tinplate; tinplate pretreated with a protective material such as chromium, titanium, titanate or aluminium; tin-free steel (TFS); galvanised steel, such as for example electro-galvanised steel; aluminium; aluminium alloy; and combinations thereof.

[0170]

[0169] The metal may be aluminium, aluminium alloy, or combinations thereof.

[0171]

[0170] Examples of suitable metal substrates include, but are not limited to, food or beverage packaging, and components used to fabricate such packaging or monobloc aerosol cans and / or tubes.

[0172]

[0171] The substrate may be a food or beverage package or component used to fabricate such packaging. Thus, there is also provided a food or beverage package comprising a surface having a coating on at least a portion thereof, the coating being derived from a post repair coating composition according to the present invention. The food or beverage packaging may be a can. Examples of cans include, but are not limited to, two-piece cans, three-piece cans and the like. Suitable examples of monobloc aerosol cans and / or tubes include, but are not limited to, deodorant and hair spray containers. Monobloc aerosol cans and / or tubes may be aluminium monobloc aerosol cans and / or tubes.

[0173]

[0172] The substrate may be a monobloc aerosol can and / or tube.

[0174]

[0173] The application of various pre-treatments and coatings to packaging is well established. Such treatments and / or coatings, for example, can be used in the case of metal cans, wherein the treatment and / or coating is used to retard or inhibit corrosion, provide a decorative coating, provide ease of handling during the manufacturing process, and the like. Coatings can be applied to the interior of such cans to prevent the contents from contacting the metal of the container. Contact between the metal and a food or beverage, for example, can lead to corrosion of a metal container, which can then contaminate the food or beverage. This is particularly true when the contents of the can are acidic in nature. The coatings applied to the interior of metal cans also help prevent corrosion in the headspace of the cans, which is the area between the fill line of the product and the can lid; corrosion in the headspace is particularly problematic with food products having a high salt content. Coatings can also be applied to the exterior of metal cans.

[0175]

[0174] The post repair coating compositions can be applied to the interior and / or the exterior of the package. The coating compositions could also be applied as a rim coat to the bottom of the can. The coating compositions can also be applied to caps and / or closures; such application can include, for example, a protective varnish that is applied after formation of the cap / closure, particularly those having a scored seam at the bottom of the cap.

[0176]

[0175] Metal coils, having wide application in many industries, are also substrates that can be coated according to the present invention. Coil coatings also typically comprise a colorant.

[0177]

[0176] The substrate may be a post-consumer recycled aluminum substrate.

[0178]

[0177] The post repair coating composition is suitably applied as a post repair coating. The coating may suitably be applied as a post repair coating for component parts of food and beverage cans. For example, the post repair coating composition may be applied as a repair coating for an easy open end for beverage cans or a full aperture easy open end for food cans. These end components are repair coated, after fabrication, by airless spraying of the post repair coating composition on to the exterior of the score line. Other uses as repair coatings include the coating of seams and welds, such as side seams for which the post repair coating composition may be applied to the area by spraying (airless or air driven) or roller coating. Repair coatings can also include protection of vulnerable areas where corrosion may be likely due to damage, these areas include flanges, rims and bottom rims where the coating may be applied by spraying, roller coating flow or dip coating.

[0179]

[0178] Thus, the post repair coating compositions may be applied to a score line, a seam, such as a side seam, a weld, a flange, a rim, a bottom rim, and / or any other vulnerable area where corrosion may be likely due to damage, of food or beverage packaging, such as a food or beverage can. The post repair coating compositions may be applied to at least a portion of an internal and / or external surface of said food and / or beverage can. For example, when the coating compositions are applied to a food and / or beverage can, the post repair coating compositions may be applied to at least a portion of an internal surface of said food and / or beverage can.

[0180]

[0179] The post repair coating compositions may be applied to the substrate by any suitable method. Methods of applying the post repair coating compositions will be well known to a person skilled in the art. Suitable application methods include, but are not limited to the following: electrocoating such as electrodeposition; spraying; electrostatic spraying; dipping; rolling; brushing; and the like. The post repair coating compositions may be applied to the substrate by spraying. Thus, the post repair coating compositions may be spray compositions. For the avoidance of doubt, by the term ‘spray composition’ and like terms as used herein is meant, unless specified otherwise, that the coating composition is suitable to be applied to a substrate by spraying, i.e. is sprayable.

[0180] According to a third aspect of the present invention there is provided a method of repairing a score line on a food or beverage package, such as a food or beverage can, the method comprising applying to the score line a post repair coating composition according to the first aspect.

[0181]

[0181] The method may further comprise the step of curing the post repair spray coating composition, such as by applying heat to a peak metal temperature (PMT) of up to 150°C.

[0182]

[0182] The peak metal temperature (PMT) as used herein refers to the temperature of the substrate, i.e. the metal surface of a food or beverage package, such as a food or beverage can.

[0183]

[0183] 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.

[0184]

[0184] Singular encompasses plural and vice versa. For example, although reference is made herein to “a” polyamine material, “an” acrylic material, “an” oxirane group, “an” alcohol group, 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.

[0185]

[0185] 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”.

[0186]

[0186] 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.

[0187]

[0187] 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 R27 each 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 -CHs, becomes methylene, -CH2-, when represented as an alkylene. Other alkylene groups should be understood accordingly.

[0188]

[0188] 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.

[0189]

[0189] 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.

[0190]

[0190] 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 a 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.

[0191]

[0191] 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.

[0192]

[0192] All of the features contained herein may be combined with any of the above aspects in any combination.

[0193]

[0193] 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.

[0194] Examples

[0195]

[0194] The following examples are intended to illustrate the invention and should not be construed as limiting the invention in any way.

[0196] Acrylic Example 1

[0197]

[0195] Acrylic example 1 was prepared according to the formulation in Table 1 and by the following process method. All amounts are given in parts by weight (pbw) unless otherwise specified. Table 1 - Formulation of Acrylic Example 1

[0198] * = tert-Butyl peroxy-3,5,5-trimethylhexanoate, commercially available from Nouryon

[0199] Process Method

[0200]

[0196] The polymerization was carried out using a reaction vessel equipped with heating, stirring, a reflux condenser, and a nitrogen blanket. Item 1 was added to the reaction vessel and heated to reflux (115-118°C). Whilst the vessel was heating to reflux, the components of item 2 (‘monomer mix’) and item 3 (‘initiator mix’) were mixed separately in different tanks. When the contents of the reactor were refluxing at a temperature of 115-118°C, the monomer mix and the initiator mix were simultaneously added to the reactor at a constant rate over a period of 240 minutes. After the addition was completed, the contents of the reactor were held at reflux (~118°C) for 120 minutes. During the hold, the monomer and initiator tanks were rinsed with items 4 and 5, respectively. After the hold, the reactor contents were cooled. The components of item 6 were added while cooling.

[0201]

[0197] The resultant acrylic polymer had the following characteristics:

[0202] Solids content 52.92% (205°C, 10 minutes, 0.5 g sample, 1 g diluent)

[0203] Viscosity 1 ,890 centipoise (spindle #7, 50 rpm @ 25°C)

[0204] %G A 31.7

[0205] EEW (solution) 880

[0206] Molecular Weight (Mn) 9,356

[0207] Molecular Weight (Mw) 22,877

[0208] Acrylic Examples 2-8

[0209]

[0198] Acrylic examples 2-8 were prepared according to the formulation in Table 2 and by the following process method. All amounts are given in parts by weight (pbw) unless otherwise specified. Table 2 - Formulation of Acrylic Examples 2-7

[0210] * = tert-Butyl peroxy-3,5,5-trimethylhexanoate

[0211]

[0199] The polymerization was carried out using a reaction vessel equipped with heating, stirring, a reflux condenser, and a nitrogen blanket. Addition of monomers and free radical initiator were linked to the reaction vessel by pumps which could be used to control the addition rate. Item 1 was added to the reaction vessel and heated to reflux (240-245°F). Whilst the vessel was heating to reflux, item 3 components were mixed in the initiator tank and item 2 components were mixed in the monomer tank. With the contents of the reactor refluxing at a temperature of 240-245°F, the contents of the monomer tank and the initiator tank were simultaneously added to the reactor at a constant rate over a period of 240 minutes. After the addition was completed, the contents of the reactor were held at reflux (~245°F) for 120 minutes. During the hold, the monomer and initiator tanks were rinsed with items 4 and 5, respectively. After the hold, the reactor contents were cooled. Item 6 was added while cooling.

[0212]

[0200] Properties of acrylic examples 2-8 are provided in Table 3 below. The theoretical Tg is calculated via the Fox equation, as provided herein. Table 3 - Properties of Acrylic Examples 2-7

[0213] Preparation of coating compositions 1-3

[0214]

[0201] Coating compositions 1 -3 were prepared according to the formulations in Tables 2A-C. All amounts are given in parts by weight (pbw) unless otherwise specified.

[0215]

[0202] The coating compositions were prepared as two-component compositions (comprised of Part A and Part B), which were stored separately as stable components, according to the formulations in Tables 2A and 2B. Part A was prepared by sequentially adding items 1 -3, as set out in Table 2A, to a vessel stirred with a high-speed mixer at 25°C. Mixing was continued for 10 minutes after the addition of all items was complete. Part B was prepared by sequentially adding items 1 -5, as set out in Table 2B, to a vessel stirred with a high-speed mixer at 25°C. Mixing was continued for 10 minutes after the addition of items was complete. The two components, Parts A and B, were then mixed in in the amounts outlined below in Table 2C, and by the following method, prior to application of the coating compositions to the substrate. Part B was added to Part A in a mixing vessel which was stirred with a high-speed mixing blade at SOO- WOO rpm at a temperature around 25°C. Mixing was continued for 10 minutes after the addition of both parts was complete. After mixing, each of the coating compositions were stored at a temperature around 25°C. They remained in a usable state for around 8 hours. Table 2A - Formulation of First Component of the Two-Part Compositions (Part A)

[0216] Table 2B - Formulation of Second Component of the Two-Part Compositions (Part B)

[0217] 1= polyamine curing agent, commercially available from Huntsman Corporation

[0218] 2= 2,5-thiophenediylbis(5-tert-butyl-1 ,3-benzoxazole), commercially available from BASF

[0219] 3= silicone surface additive, commercially available from BYK Chemie

[0220] Table 2C - Formulation of Coating Compositions 1-3

[0221] Comparative Coating Composition 1

[0222]

[0203] Comparative coating composition 1 is a 2K coating composition which is a 50:50 blend of PPG2982-803 / A (Part A) and PPG2982-807A (Part B), both commercially available from PPG. The comparative coating is based on a bisphenol A (BPA)-epoxy and polyamine hardener.

[0223] Preparation of coating compositions 4-10

[0224]

[0204] Coating compositions 4-10 were prepared according to the formulations in Table 3. All amounts are given in parts by weight (pbw) unless otherwise specified. Table 3 - Formulation of Coating Compositions 4-10

[0225] 1= polyamine curing agent, commercially available from Huntsman Corporation

[0226] Coating application and drying

[0227]

[0205] The coating compositions were applied to pre-coated tinplate full aperture easy open ends (FAEOEs), having a score line, by aerograph coating or by spraying as follows.

[0228]

[0206] Aerograph application: the coating compositions were applied to a tinplate full aperture easy open end (as routinely used as a component of food or beverage cans) pre-coated with clear, gold or white pigmented lacquer with print markings. As a preliminary procedure screen for dry film resistance, the coating compositions were applied with a paint aerograph in a strip of 10 to 20 mm over the score line. After application, the ends were dried for 60 seconds in an oven at a temperature of 120°C to 150°C (to achieve a peak metal temperature (PMT) from 110°C to 140°C) to produce a cured film.

[0229]

[0207] Spray application: for a more in-depth investigation, and to align with industrial application, the coating compositions were applied to a tinplate full aperture easy open end precoated with clear, gold or white pigmented lacquer with print markings with an airless spray gun. The coating compositions were applied in a strip 5 to 25 mm wide over the score line. After application, the ends were cured in an oven for 60 second at an oven temperature of 120°C (to achieve a peak metal temperature (PMT) from between 110°C and 140°C) to produce a cured film.

[0230]

[0208] The coated ends obtained were then tested no later than 3 hours after completion of the drying process in accordance with the following test methods.

[0231] Test Methods

[0232]

[0209] The performance of the coatings as a repair / protective layer over the score line was evaluated using the following tests:

[0210] Blush resistance: the industrial process for processing or sterilisation of cans containing various food fillings often uses water which is at higher pH (pH 9 -10). Corrosion resistance to a solution of Na2CO3 in water is known to be an efficient method to test the ability of coatings to withstand such industrial processes.

[0233]

[0211] Blush is white colouration of the film caused by water penetration and entrapment. To assess the resistance to blush, the coated ends were sterilised in an autoclave for 1 hour at 130°C in i) water and ii) a 0.05% solution of NaaCOs in water. The ends were completely immersed in the liquid in each case. After sterilisation, the film in the region of the score line was evaluated visually under an optical microscope, and the amount of blush was rated from 0 to 5. Grade 0 corresponds to perfect film appearance with no visible blush. Grade 5 corresponds to complete attack of the film across the whole of the score line. Grade 1 corresponds to light blush which is acceptable for food / beverage applications.

[0234]

[0212] Liquid phase test results correspond to ends that were fully immersed in the relevant solution. Vapor phase test results correspond to ends that were half immersed in the relevant solution.

[0235]

[0213] Corrosion resistance: industrial processing or sterilisation of cans containing various food fillings requires sufficient coating resistance against high pressure and high temperature conditions. Corrosion resistance to a CuSO4 solution is known to be an efficient method to test the ability of coatings to withstand such industrial processes. The coated ends were immersed in a CuSO4 solution (10 % w / w CuSO4, 10% w / w HCI (37%), 80 % w / w deionized water) for five minutes. After 5 minutes, the ends were flushed with water and dried. The score line was examined for defects under an optical microscope. The appearance of the score line was rated between 0 and 5. Grade 0 corresponds to perfect film appearance with no visible corrosion or copper deposition. Grade 5 corresponds to complete attack of the film across the whole of the score line.

[0236]

[0214] Bubble formation: the formation of bubbles / defects trapped within the film or in the coating-metal interface in the region of the scoreline was examined visually under an optical microscope. The appearance of bubbles / defects was rated between 0 and 5. Rating grade 0 corresponds to no bubbles seen along the score line and grade 5 corresponds to bubbles covering all of the score line.

[0237]

[0215] Adhesion: film adhesion was assessed after sterilisation in a 1% solution of Teepol (sodium dodecyl benzene sulphonate) in water for 1 hour at 130°C. After sterilisation, the coating was crosshatched and checked for removal with 3M 610 tape. The degree of removal was assessed visually, and adhesion was rated from 0 to 5. Grade 0 corresponds to good adhesion with no removal of coating and grade 5 corresponds to complete loss of adhesion with complete removal of the coating.

[0238]

[0216] Yellowing: to assess yellowing the coating was applied on ends which are coated with white enamel and sterilized in a 1% Teepol (sodium dodecyl benzene sulphonate, detergent) solution in water for 1 hour at 130°C. Grade 0 corresponds to no yellowing and Grade 5 to a high yellowing level.

[0239]

[0217] Tackiness: the coating was manually assessed by touching the coating to see if there was any tackiness / stickiness after curing. The tackiness was rated from 0 to 5. Grade 5 corresponds to very tacky. Grade 0 corresponds to no tackiness.

[0240]

[0218] Test results are shown in Tables 4, 5A, 5B and 5C below.

[0241] Results

[0242] Table 4 - Test results for aerograph applied coating compositions

[0243] Table 5A - Test results for spray applied coating compositions Table 5A - Test results for spray applied coating compositions

[0244] Table 5C - Test results for spray applied coating compositions

[0245]

[0219] Coating compositions 4-10 also all showed an adhesion rating of 0 (zero).

[0246]

[0220] The results show that the coating compositions of the present invention perform as good as, or better than, that of the comparative example. It can be seen from the examples that a coating composition in accordance with the present invention provides a post repair coating that i) can be cured at a lower curing temperature than would typically be expected (180-220°C), ii) has a workable pot life (of at least 8 hours), iii) can be applied using airless spray equipment, and iv) provides good corrosion resistance to the exposed metal score line to which it has been applied (which is at least comparable to the corrosion resistance provided by the comparative example).

[0247]

[0221] 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.

[0248]

[0222] 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.

[0249]

[0223] 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.

[0250]

[0224] 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 this specification (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 post repair coating composition for a food or beverage package, the coating composition comprising: a) an acrylic material having oxirane-functionality; and b) a polyamine material, wherein the coating composition is substantially free of bisphenol A (BPA), bisphenol F (BPF) and derivatives thereof.

2. The post repair coating composition according to claim 1, wherein the coating composition is a two-component system, wherein the two-component system comprises a first component comprising the acrylic material (a) and a second component comprising the polyamine material (b).

3. The post repair coating composition according to any one of claims 1 or 2, wherein the coating composition comprises a liquid carrier comprising water.

4. The post repair coating composition according to any one of claims 1 -3, wherein the acrylic material comprises a solution polymerised acrylic material and / or an emulsion polymerised acrylic material.

5. The post repair coating composition according to any one of claims 1 -4, wherein the acrylic material is formed from a reaction mixture, the reaction mixture comprising one or more acrylic monomer(s), for example selected from alkyl (alk)acrylate, alkyl (meth)acrylate, and / or (alk)acrylic acid.

6. The post repair coating composition according to claim 5, wherein at least one of the acrylic monomers comprises an oxirane-functional group.

7. The post repair coating composition according to claim 6, wherein the oxirane-functional acrylic monomer comprises glycidyl methacrylate.

8. The post repair coating composition according to any one of claims 6 or 7, wherein the acrylic material is formed from a reaction mixture comprising from 15 to 35 wt%, such as from 20 to 35 wt%, of the oxirane-functional acrylic monomer based on the total weight of monomers present.

9. The post repair coating composition according to any one of claims 5-8, wherein the reaction mixture is substantially free of styrene.

10. The post repair coating composition according to any one of claims 1 -9, wherein the acrylic material has a calculated glass transition temperature (Tg) of at least 25°C, such as from 25 to 60°C.

11. The post repair coating composition according to any one of claims 1-10, wherein the acrylic material has an epoxy equivalent weight (EEW) on solution of at least 800, such as at least 850, such as from 800 to 2,000, such as from 850 to 2,000.

12. The post repair coating composition according to any one of claims 1-11 , wherein the acrylic material has a number-average molecular weight (Mn) of at least 8,000 Da, such as from 8,000 to 15,000 Da.

13. The post repair spray according to any one of claims 1 -12, wherein the polyamine material comprises an aliphatic and / or cycloaliphatic polyamine having at least two primary amine groups, and optionally at least one secondary and / or tertiary amine group.

14. The post repair spray according to claim 13, wherein the polyamine material further comprises at least amide group, such as at least one secondary and / or tertiary amide group.

15. The post repair coating composition according to any one of claims 1-14, wherein the polyamine material has an amine value of at least 200 mg KOH / g, such as at least 250 mg KOH / g, such as at least 300 mg KOH / g.

16. The post repair coating composition according to any one of claims 1-15, wherein the composition comprises at least 50 wt%, such as at least 70 wt%, such as at least 75 wt%, such as at least 80 wt% of the acrylic material based on the total solid weight of the composition.

17. The post repair coating composition according to any one of claims 2-16, wherein the first component of the two-component system comprises at least 80 wt%, such as at least 90 wt%, such as at least 95 wt%, such as at least 99 wt% of the acrylic material based on the total solid weight of the first component.

18. The post repair coating composition according to any one of claims 1-17, wherein the composition comprises from 2 to 20 wt%, such as from 5 to 15 wt%, of the polyamine material based on the total solid weight of the composition.

19. The post repair spray coating composition according to any one of claims 2-18, wherein the second component of the two-component system comprises at least 80 wt%, such as at least 90 wt%, such as at least 95 wt%, such as at least 99 wt% of the polyamine material based on the total solid weight of the second component.

20. The post repair spray coating composition according to any one of claims 1-19, wherein the weight ratio of acrylic material to polyamine material is from 20:1 to 1 :1 , such as from 10:1 to 2:1 , such as from 10:1 to 5:1 .

21. The post repair coating composition according to any one of claims 1-20, wherein the composition is a spray composition.

22. A food or beverage package, such as a food or beverage can, comprising a surface having a coating on at least a portion thereof, the coating being derived from a post repair coating composition according to any one of claims 1 -20.

23. A method of repairing a score line on a food or beverage packages, such as a food or beverage can, the method comprising applying to the score line a post repair coating composition according to any one of claims 1-20.

24. The method according to claim 23, wherein the method further comprises the step of curing the post repair spray coating composition, such as by applying heat to a peak metal temperature (PMT) of up to 150°C.

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