Hydrophilic copolymer, coating composition containing same, and anti-fogging use thereof

Abstract

The present invention relates to a hydrophilic copolymer and a coating composition containing the same, as well as its anti-fog application. The hydrophilic copolymer contains repeating units derived from a siloxy-functionalized monomer and a hydrophilic organic monomer. The hydrophilic copolymer and coating composition can be used to impart anti-fog and scratch resistance. The present invention also relates to an article comprising a coating formed from the coating composition.

Description

[Technical Field]

[0001] The present invention relates to a hydrophilic copolymer and a coating composition comprising the copolymer. In particular, the hydrophilic copolymer comprises repeating units derived from a siloxy-functionalized monomer and a hydrophilic organic monomer. The copolymer and coating composition provide anti-fogging and / or scratch resistance to plastic substrates or articles. The present invention also relates to an article comprising a coating film formed from the coating composition. [Background technology]

[0002] Transparent plastic substrates, such as those made from polycarbonate and poly(meth)acrylate, are widely used in automotive and architectural applications, for example, as safety glass, protective shields, etc. Such transparent substrates suffer from the disadvantage that when the surface temperature of the substrate is below the dew point of atmospheric moisture, droplets of water condense on the surface, causing fogging and a hazy appearance.

[0003] A conventional approach to solving the problem of fogging is to coat a hydrophilic coating on the surface of a transparent substrate. Typical hydrophilic coating solutions used for anti-fogging purposes are based on low-molecular-weight dispersants or surfactants with hydrophilic groups. Hydrophilic coatings formed from such coating solutions generally have poor scratch resistance. To improve scratch resistance, interest has grown in polymer-based coatings formed by crosslinking reactions, such as using polyisocyanates as crosslinking agents to react with hydroxyl groups in the polymer. While the resulting crosslinked system improves scratch resistance to some extent, it is still insufficient for practical use. Crosslinking of epoxy groups can also improve scratch resistance. However, epoxy groups tend to cause yellowing, thereby degrading the transparency and durability of the coating.

[0004] Additionally, due to the presence of hydrophilic groups in the coating, moisture from the surrounding environment is adsorbed into the hydrophilic coating, causing the performance of the coating to deteriorate over time. The adhesion of the coating to the substrate is also adversely affected.

[0005] Therefore, there remains a need to provide an anti-fog coating that has sufficient scratch resistance for practical use, strong adhesion to the substrate, and performance that does not deteriorate over time. Summary of the Invention

[0006] In an embodiment, the present invention provides: A first repeating unit represented by general formula (1): [ka] A second repeating unit represented by general formula (2): [ka] and optionally A third repeating unit represented by general formula (3): [ka] In particular, the hydrophilic copolymer comprises R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 9 are each independently selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally containing a heteroatom; X is -(L F ) m -L 1 -Si(OR 11 ) a (R 12 ) 3-aa monovalent siloxy-containing group represented by Y is -(L F ) m -(L 2 ) n -C(O)-N(R 21 )(R 22 ) a monovalent hydrophilic group represented by Z is -(L F ) m -(L 3 ) n -C(O)-L 4 -R 31 is a monovalent organic group represented by where L F each independently represents a divalent organic group selected from -O-, -N(R)-, -C(O)-, -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O-, or -OC(O)N(R)-, where R represents a hydrogen atom or an alkyl group having from 1 to about 6 carbon atoms; L 1 , L 2 and L 3 each independently represents a substituted or unsubstituted divalent hydrocarbon group having from 1 to about 20 carbon atoms and optionally containing a heteroatom; L 4 is selected from an oxygen atom or a sulfur atom; R 11 are each independently an alkyl group having from 1 to about 12 carbon atoms; R 12 are each independently a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally containing heteroatoms; R 21 and R 22 are each independently selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally containing a heteroatom; R 31 is selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally having one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl; each of the subscripts m and n is independently 0 or 1; and The subscript a is 1, 2, or 3.

[0007] In another embodiment, the present invention relates to a method for preparing a hydrophilic copolymer according to the above embodiment, wherein the hydrophilic copolymer has the formula C(R 1 )(R 2 )=C(R 3 )X, a first monomer of formula C(R 4 )(R 5 )=C(R 6 ) Y, and optionally a second monomer of formula C(R 7 )(R 8 )=C(R 9 ) Z undergoes radical polymerization in the presence of an initiator, where R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , X, Y and Z are as defined above.

[0008] In another embodiment, the present invention relates to a coating composition comprising a hydrophilic copolymer according to the above embodiment. In an embodiment, the coating composition is a curable coating composition.

[0009] In another embodiment, the present invention relates to a two-pack or multi-pack coating system comprising at least a first package composition and a second package composition, and optionally a third package composition, wherein the first package composition comprises a hydrophilic copolymer according to the above-described embodiments; and the second package composition comprises a catalyst.

[0010] In another further embodiment, the present invention relates to a method for preparing a coating composition, comprising blending a hydrophilic copolymer according to the above embodiment with a catalyst, and optionally with a component selected from a surfactant, a solvent, a crosslinker, an adhesion promoter, or a combination of two or more thereof.

[0011] In another further embodiment, the present invention relates to a cured composition formed from a curable coating composition according to the above embodiment. In some embodiments, the cured composition is formed in the absence of a crosslinker.

[0012] In yet another embodiment, the present invention relates to an article comprising a substrate, wherein at least a portion of a surface of the substrate comprises a coating formed from a coating composition according to the above-described aspect. In some embodiments, the article is selected from safety glass, a protective shield, an automobile headlight, a windshield, eyeglasses, goggles, a mirror, a transparent container, a window, or a camera lens.

[0013] In yet another embodiment, the present invention relates to a method for imparting anti-fog and / or scratch resistance to a substrate or article, comprising applying to the substrate or article any of the hydrophilic copolymers, coating compositions, two-pack or multi-pack coating systems, or cured compositions according to the above embodiments.

[0014] According to the present invention, a coating composition containing the hydrophilic copolymer of the present application can form a coating film that is transparent, exhibits excellent anti-fogging properties, has strong adhesion to transparent substrates such as polycarbonate and (meth)acrylate, and has sufficient scratch resistance for practical use. In some preferred embodiments, the coating film according to the present invention exhibits excellent durability, and the anti-fogging properties and adhesive performance can be maintained even after immersion in water at 40°C for 1 hour and then drying at 80°C for 30 minutes. DETAILED DESCRIPTION OF THE INVENTION

[0015] In the specification and claims of this application, the following terms and expressions shall be understood as follows.

[0016] The singular forms "a," "an," and "the" include plurals, and reference to a particular number includes at least that particular number unless the context clearly indicates otherwise.

[0017] The use of any and all examples or exemplary language (e.g., "such as") presented in this application is intended merely to better illustrate the invention and does not pose a limitation on the scope of the invention unless specifically stated otherwise.

[0018] No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0019] The terms "comprise," "include," "contain," and grammatical equivalents thereof are understood to be inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps, and also include the more restrictive terms "consisting of" and "consisting essentially of."

[0020] Other than in the examples, or unless otherwise noted, all numbers expressing amounts of substances, temperatures, lengths of time, quantified properties of substances, and the like described in this specification and claims are understood to be modified in all instances by the term "about," whether or not the term "about" is used in the expression.

[0021] Any numerical range recited herein is understood to include all subranges within that range, and any combination of the various endpoints of such range or subrange.

[0022] Furthermore, all compounds, materials, or substances explicitly or implicitly disclosed and / or claimed herein as belonging to a group of structurally, compositionally, and / or functionally related compounds, materials, or substances are understood to include the individual members of that group and all combinations thereof.

[0023] Throughout this disclosure, the term "hydrocarbon group" means any hydrocarbon, whether saturated or unsaturated, aliphatic or aromatic, cyclic or acyclic, from which one or more hydrogen atoms have been removed; and refers to any of alkyl, alkenyl, alkynyl, cyclic alkyl, cyclic alkenyl, cyclic alkynyl, aryl, aralkyl, and alkaryl groups, which may optionally contain one or more heteroatoms. In one embodiment, the hydrocarbon group may contain up to about 20 carbon atoms, and in another embodiment, up to about 16 carbon atoms.

[0024] The term "alkyl" refers to any monovalent, saturated, straight-chain, branched-chain, or cyclic hydrocarbon group. Examples of alkyl include methyl, ethyl, propyl, butyl, and cyclohexyl. The term "alkenyl" refers to any monovalent, straight-chain, branched-chain, or cyclic hydrocarbon group containing one or more carbon-carbon double bonds, where the bonding position of the group can be either the carbon-carbon double bond or another position. Examples of alkenyl include vinyl, propenyl, allyl, methallyl, and cyclohexylvinyl. The term "alkynyl" refers to any monovalent straight-chain, branched-chain, or cyclic hydrocarbon group containing one or more carbon-carbon triple bonds and, optionally, one or more carbon-carbon double bonds, where the group can be attached through the carbon-carbon triple bond, the carbon-carbon double bond, or elsewhere. Examples of alkynyl include acetylenyl, propargyl, and methylacetylenyl.

[0025] As used herein, the term "aryl" refers to any monovalent aromatic hydrocarbon having from about 6 to about 30 carbon atoms, preferably from about 6 to about 20 carbon atoms, and more preferably from about 6 to about 18 carbon atoms. Examples of aryl include phenyl and naphthyl. The term "aralkyl" refers to any alkyl group (as defined herein) in which one or more hydrogen atoms have been replaced with an equal number of similar and / or different aryl groups (as defined herein). Examples of aralkyl include benzyl and phenethyl. The term "alkaryl" refers to any aryl group (as defined herein) in which one or more hydrogen atoms have been replaced with an equal number of similar and / or different alkyl groups (as defined herein). Examples of alkaryl include tolyl and xylyl.

[0026] The term "heteroatom" means any of the elements in Groups 13-17, excluding carbon, and includes, for example, oxygen, nitrogen, silicon, sulfur, phosphorus, fluorine, chlorine, bromine, and iodine. In some embodiments, the heteroatom is a halogen atom selected from fluorine, chlorine, bromine, and iodine. In some embodiments, the heteroatom is oxygen, nitrogen, or sulfur.

[0027] Useful monovalent hydrocarbon groups include: straight or branched chain alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl such as n-hexyl, heptyl such as n-heptyl, octyl such as n-octyl, isooctyl, and 2,2,4-trimethylpentyl, nonyl such as n-nonyl, decyl such as n-decyl, and cyclopentyl, cyclohex ... cycloalkyls such as cycloheptyl, and methylcyclohexyl; alkenyl groups, such as straight-chain or branched alkenyl groups, for example, vinyl, propenyl, allyl, and methallyl, and cyclic alkenyls, for example, cyclohexenyl; alkynyl groups, for example, acetylenyl, propargyl, and methylacetylenyl; aryl groups, for example, phenyl and naphthyl; alkaryl groups, for example, o-, m-, and p-tolyl, xylyl; and aralkyl groups, for example, phenethyl and benzyl.

[0028] Useful divalent hydrocarbon groups include alkylene, alkenylene, alkynylene, or any combination of two or more thereof, which may optionally contain one or more heteroatoms, such as oxygen, nitrogen, sulfur, or halogen atoms. In some embodiments, the divalent hydrocarbon group may optionally contain one or more functional groups, including, for example, a hydroxyl group, a mercapto group, an ether group, an ester group, an amine group, or a carboxyl group. The divalent hydrocarbon group may contain 1 to about 20 carbon atoms, for example, 1 to about 16 carbon atoms, preferably 1 to about 12 carbon atoms, and more preferably about 3 to about 10 carbon atoms.

[0029] A "hydrophilic" material (e.g., hydrophilic group, hydrophilic monomer, hydrophilic (co)polymer, etc.) refers to a material that has an affinity for or can absorb water. A hydrophilic material may be soluble or insoluble in water. In some embodiments, a hydrophilic material may contain hydrophilic and hydrophobic portions, but the hydrophobic portions are present in relatively insignificant amounts, and the material as a whole is hydrophilic.

[0030] In an embodiment, the present invention provides a hydrophilic copolymer comprising repeating units derived from a siloxy-functional monomer and a hydrophilic organic monomer. Due to the repeating units functionalized with a siloxy group, the hydrophilic copolymer can be crosslinked even without a crosslinking agent, resulting in a cured product with high crosslink density. The repeating units derived from the hydrophilic monomer can provide the copolymer with sufficient hydrophilic properties and exhibit anti-fogging performance. The hydrophilic copolymer can further comprise repeating units derived from an additional organic monomer, which can adjust the properties of the copolymer, such as its hydrophilic properties.

[0031] Preferably, the hydrophilic copolymer of the present application is: A first repeating unit represented by general formula (1): [ka] A second repeating unit represented by general formula (2): [ka] and optionally A third repeating unit represented by general formula (3): [ka] wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 9are each independently selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms, preferably from 1 to about 12 carbon atoms, and more preferably from 1 to about 8 carbon atoms, or from 1 to about 6 carbon atoms. The hydrocarbon group herein optionally contains a heteroatom, such as a halogen atom, or an oxygen, nitrogen, or sulfur atom.

[0032] X in formula (1) is -(L F ) m -L 1 -Si(OR 11 ) a (R 12 ) 3-a where L is a monovalent siloxy-containing group represented by F represents a divalent organic group selected from -O-, -N(R)-, -C(O)-, -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O- or -OC(O)N(R)-, where R represents a hydrogen atom or an alkyl group having 1 to about 6 carbon atoms, preferably 1 to about 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl; and in one embodiment, L F is selected from -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O-, or -OC(O)N(R)-; preferably -C(O)O- or -C(O)N(R)-. 1 L represents a substituted or unsubstituted divalent hydrocarbon group having 1 to about 20 carbon atoms, preferably 1 to about 16 carbon atoms, and more preferably 1 to about 10 carbon atoms, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. 1 may optionally contain one or more heteroatoms selected from, for example, oxygen, nitrogen, or sulfur atoms. 1 may optionally include one or more functional groups selected from, for example, hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups. 1may be a straight or branched chain alkylene group, a cycloalkylene group, an arylene group, or any combination of two or more thereof, and may contain or be substituted with one or more functional groups selected from, for example, hydroxyl groups, mercapto groups, ether groups, ester groups, amine groups, amide groups, or carboxyl groups. 1 R is a straight or branched chain alkylene group having 2 to 8, and preferably 3 to 6, carbon atoms. 11 R is each independently an alkyl group having from 1 to about 12 carbon atoms, preferably from 1 to 8 carbon atoms, and more preferably from 1 to 6 carbon atoms, examples of which include methyl, ethyl, n-propyl, and isopropyl. 12 R is each independently a monovalent hydrocarbon group having 1 to about 16 carbon atoms, preferably 1 to about 12 carbon atoms, more preferably 1 to about 8 carbon atoms, or 1 to about 6 carbon atoms. 12 may be optionally substituted with a heteroatom, for example a halogen atom such as Cl or Br. The subscript m is 0 or 1; and a is 1, 2, or 3.

[0033] In an embodiment, X in formula (1) is -L 1 -Si(OR 11 ) a (R 12 ) 3-a or -L F -L 1 -Si(OR 11 ) a (R 12 ) 3-a and L F , L 1 , R 11 , R 12 and subscript a are each as defined above. In one embodiment, X is -L F -L 1 -Si(OR 11 ) a (R 12 ) 3-a where L F is -C(O)O- or -C(O)N(R)-;L1 is a linear or branched alkylene group having 2 to 8, and preferably 3 to 6, carbon atoms, optionally containing one or more functional groups selected from, for example, hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups; R 11 are each independently an alkyl group having from 1 to about 8 carbon atoms; R 12 are each independently selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms; and a is 2 or 3.

[0034] Y in equation (2) is -(L F ) m -(L 2 ) n -C(O)-N(R 21 )(R 22 ) where L F represents a divalent organic group selected from -O-, -N(R)-, -C(O)-, -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O- or -OC(O)N(R)-, where R represents a hydrogen atom or an alkyl group having 1 to about 6 carbon atoms, preferably 1 to about 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl; and in one embodiment, L F is selected from -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O-, or -OC(O)N(R)-; preferably -C(O)O- or -C(O)N(R)-. 2 L represents a substituted or unsubstituted divalent hydrocarbon group having 1 to about 20 carbon atoms, preferably 1 to about 16 carbon atoms, and more preferably 1 to about 10 carbon atoms, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. 2may optionally contain one or more heteroatoms selected from, for example, oxygen, nitrogen, or sulfur atoms. 2 may optionally include one or more functional groups selected from, for example, hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups. 2 R may be a straight or branched chain alkylene group, a cycloalkylene group, an arylene group, or any combination of two or more thereof, and may contain or be substituted with one or more functional groups selected from, for example, a hydroxyl group, a mercapto group, an ether group, an ester group, an amine group, an amide group, or a carboxyl group. 21 and R 22 R may each independently be selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms, preferably from 1 to about 12 carbon atoms, and more preferably from 1 to about 8 carbon atoms, or from 1 to about 6 carbon atoms. 21 and R 22 may optionally contain one or more heteroatoms, such as O, S, or N. For example, R 21 and R 22 R may each independently be selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms. 21 and R 22 Examples of include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, phenyl, benzyl, ethylphenyl, tolyl, or xylyl. The subscripts m and n are independently 0 or 1.

[0035] In an embodiment, Y in formula (2) is: -L F -L 2 -C(O)-N(R 21 )(R 22 ) (Y1) Here, L Fis selected from -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O-, or -OC(O)N(R)-; L 2 R is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl; 21 and R 22 are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; -L F -C(O)-N(R 21 )(R 22 ) (Y2) Here, L F is selected from -O-, -N(R)-, -C(O)-, -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O-, or -OC(O)N(R)-; R 21 and R 22 are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; -L 2 -C(O)-N(R 21 )(R 22 ) (Y3) Here, L 2 R is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl; 21 and R 22are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; or -C(O)-N(R 21 )(R 22 ) (Y4) where R 21 and R 22 are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms.

[0036] In one embodiment, Y in formula (2) is selected from the above formulas (Y1), (Y2), (Y3) or (Y4), wherein R 21 and R 22 are each independently selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms. According to this embodiment, the second repeat unit may contribute to improved long-term anti-fogging properties of coatings formed from the hydrophilic copolymer.

[0037] Z-(L F ) m -(L 3 ) n -C(O)-L 4 -R 31 where L is a monovalent organic group represented by Frepresents a divalent organic group selected from -O-, -N(R)-, -C(O)-, -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O- or -OC(O)N(R)-, where R represents a hydrogen atom or an alkyl group having 1 to about 6 carbon atoms, preferably 1 to about 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl; and in one embodiment, L F is selected from -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O-, or -OC(O)N(R)-; preferably -C(O)O- or -C(O)N(R)-. 3 L represents a substituted or unsubstituted divalent hydrocarbon group having 1 to about 20 carbon atoms, preferably 1 to about 16 carbon atoms, and more preferably 1 to about 10 carbon atoms, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. 3 may optionally contain one or more heteroatoms selected from, for example, oxygen, nitrogen, or sulfur atoms. 3 may optionally include one or more functional groups selected from, for example, hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups. 3 L is a straight or branched chain alkylene group, a cycloalkylene group, an arylene group, or any combination of two or more thereof, which may contain or be substituted with one or more functional groups selected from, for example, a hydroxyl group, a mercapto group, an ether group, an ester group, an amine group, an amide group, or a carboxyl group. 4 is selected from an oxygen atom or a sulfur atom. 31 R may be selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms, preferably from 1 to about 12 carbon atoms, more preferably from 1 to about 8 carbon atoms, or from 1 to about 6 carbon atoms. 31may optionally contain one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl groups. The subscripts m and n are independently 0 or 1.

[0038] In one embodiment, Z in formula (3) is: -L F -L 3 -C(O)-OR 31 or -L F -L 3 -C(O)-SR 31 , where L F is selected from -OC(O)-, -C(O)O-, -N(R)C(O)-, -C(O)N(R)-, -N(R)C(O)O-, or -OC(O)N(R)-; L 3 is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl; and R 31 is a hydrogen atom or optionally substituted with one or more functional groups selected from a hydroxyl group, a mercapto group, an ether group, an ester group, an amine group, or a carboxyl group, and is selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms; -L F -C(O)-OR 31 or -L F -C(O)-SR 31 , where L F is selected from —O—, —N(R)—, —C(O)—, —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—; and R 31is a hydrogen atom or optionally substituted with one or more functional groups selected from a hydroxyl group, a mercapto group, an ether group, an ester group, an amine group, or a carboxyl group, and is selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms; -L 3 -C(O)-OR 31 or -L 3 -C(O)-SR 31 , where L 3 is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl; and R 31 is a hydrogen atom or optionally substituted with one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl groups, and is selected from an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; or -C(O)-OR 31 or -C(O)-SR 31 , where R 31 is a hydrogen atom or optionally substituted with one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl groups, and is selected from an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms.

[0039] The properties of the hydrophilic copolymer and the coating compositions formed therefrom can be controlled or adjusted by varying the molar ratios of the various repeating units (i.e., the monomers from which the repeating units are derived) of the copolymer. In embodiments, the first repeating unit represents about 1 mol% to about 40 mol%, preferably about 2 mol% to about 35 mol%, more preferably about 3 mol% to about 30 mol%, such as about 4 mol% to about 25 mol%, or about 5 mol% to about 20 mol% of the hydrophilic copolymer. A high molar ratio of the first repeating unit is advantageous from the standpoint of long-term anti-fogging properties of coatings formed from the hydrophilic copolymer. The second repeating unit represents about 25 mol% to about 85 mol%, preferably about 30 mol% to about 80 mol%, and more preferably about 35 mol% to about 75 mol%, such as about 40 mol% to about 70 mol%, or about 45 mol% to about 65 mol% of the hydrophilic copolymer. The third repeat unit represents about 0 mol% to about 50 mol%, preferably about 5 mol% to about 45 mol%, and more preferably about 10 mol% to about 40 mol%, such as about 15 mol% to about 39 mol%, or about 20 mol% to about 38 mol% of the hydrophilic polymer. In embodiments, when a third repeat unit is present, the molar ratio of the second repeat unit to the third repeat unit may vary from about 1:1 to about 5:1, preferably from about 1.1:1 to about 4:1, and more preferably from about 1.2:1 to about 3:1.

[0040] The molecular weight of the hydrophilic copolymer may vary depending on the polymerization conditions, including, for example, the monomers and their relative amounts used to form the copolymer, the polymerization temperature and time, etc. In embodiments, the hydrophilic copolymers herein may have a weight average molecular weight (Mw) of about 50,000 to 500,000, preferably about 60,000 to 400,000, and more preferably 70,000 to 300,000, as measured by gel permeation chromatography (GPC) using polystyrene standards; and a number average molecular weight (Mn) of about 5,000 to 120,000, preferably about 6,000 to 90,000, and more preferably 7,000 to 600,000.

[0041] In an embodiment, the hydrophilic copolymer is a copolymer of a first and a second repeat unit. In a preferred embodiment, the hydrophilic copolymer is a terpolymer of a first, a second, and a third repeat unit.

[0042] The hydrophilic copolymers herein may be prepared by radical polymerization, for example by radical addition polymerization of monomers corresponding to the respective repeating units. These monomers have the formula C(R 1 )(R 2 )=C(R 3 a first monomer which is a siloxy-functionalized monomer of formula C(R 4 )(R 5 )=C(R 6 )Y, and optionally a second monomer which is a hydrophilic organic monomer of formula C(R 7 )(R 8 )=C(R 9 )Z, wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 Each of X, Y, and Z is the same as defined above for formulas (1), (2), and (3). Radical polymerization is well known in the art, and the specific conditions for carrying out the radical polymerization can be selected depending on the monomers used to form the hydrophilic copolymer. For example, the radical polymerization may be carried out at a temperature ranging from about 40° C. to about 100° C. for a time period of about 1 to about 10 hours. The radical polymerization can be carried out in the presence of an initiator. The initiator can be, for example, a thermal initiator or a photoinitiator.

[0043] Examples of suitable thermal initiators include, but are not limited to, azo initiators, inorganic peroxide initiators, or organic peroxide initiators, such as an azo initiator selected from 2,2'-azobis-(2-methylpropionitrile), 2,2'-azobis-(2-methylbutanenitrile), or 2,2'-azobis-(2,4-dimethylvaleronitrile); an inorganic peroxide initiator selected from ammonium persulfate, sodium persulfate, or potassium persulfate; and an organic peroxide initiator selected from benzoyl peroxide or dilauroyl peroxide. In an embodiment, the thermal initiator is 2,2'-azobis-(2-methylpropionitrile) (AIBN) or 2,2'-azobis-(2,4-dimethylvaleronitrile) (ABVN).

[0044] Examples of suitable photoinitiators include, but are not limited to, benzoin methyl ether, diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone (HMPP), 1-hydroxycyclohexyl phenyl ketone, and benzoylphosphine oxides, such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

[0045] The radical polymerization may be carried out in a solvent. Illustrative examples of solvents include, but are not limited to, hydrocarbon solvents, alcohol solvents, ether solvents, amide solvents, ester solvents, and halohydrocarbon solvents. Examples of hydrocarbon solvents include n-hexane, n-pentane, benzene, toluene, and xylene. Examples of alcohol solvents include C1-C5 alcohols, such as methanol, ethanol, propanol, isopropanol (IPA), n-butanol, t-butanol, methoxypropanol, and methoxybutanol. Examples of ether solvents include diethyl ether, diisopropyl ether, methyl-t-butyl ether, tetrahydrofuran (THF), cyclopentyl methyl ether, dimethoxyethane, and 1,4-dioxane. Examples of amide solvents include dimethylformamide (DMF), dimethylacetamide (DMAc), and N-methyl-2-pyrrolidone (NMP). Examples of ester solvents include C1-C4 alkyl acetic acid esters, such as ethyl acetate. Examples of halohydrocarbon solvents include chloroform, methylene chloride, and 1,2-dichloroethane. These solvents may be used alone or in combination of two or more. In some embodiments, amide solvents, such as dimethylformamide (DMF) and dimethylacetamide (DMAc), are used to prepare the hydrophilic copolymers of the present application.

[0046] In another embodiment, the present invention provides a coating composition comprising a hydrophilic copolymer according to the above-described embodiment, which may be present in an amount ranging from about 30% to about 99.9% by weight, preferably from about 35% to about 99% by weight, more preferably from about 40% to about 98% by weight, and even more preferably from about 45% to about 97% by weight, based on the total solids content of the composition.

[0047] The composition may further comprise a component selected from a catalyst, a surfactant, a solvent, a crosslinker, or any combination of two or more of these.

[0048] Practical examples of catalysts that may be used in the coating compositions of the present application include, but are not limited to, catalysts of the formula [(R 41 )4N] + [OC(O)R 42 ] - and tetraalkylammonium carboxylates of the formula: 41 is selected from alkyl groups having 1 to about 6 carbon atoms, and R 42 is selected from a hydrogen atom, an alkyl group having from 1 to about 10 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms. 41 is an alkyl group having 1 to about 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, or isobutyl. 42 is methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, 2-ethylhexyl, phenyl, or benzyl. For example, tetraalkylammonium carboxylate catalysts include, but are not limited to, tetrabutylammonium carboxylates, such as tetrabutylammonium formate, tetra-n-butylammonium acetate (TBAA), tetra-n-butylammonium propionate, tetra-n-butylammonium-2-ethylhexanoate, and tetra-n-butylammonium benzoate; and tetramethylammonium acetate, tetramethylammonium-2-ethylhexanoate, tetramethylammonium benzoate, tetraethylammonium acetate, tetraisopropylammonium acetate, and tetrahexylammonium acetate. Among these catalysts, tetrabutylammonium carboxylate catalysts are generally preferred, and tetra-n-butylammonium acetate and tetra-n-butylammonium formate are more preferred.

[0049] The catalyst may be present in the coating composition in at least a catalytically effective amount, which in most cases may range from about 0.1% to about 5% by weight, preferably from about 0.2% to about 4.5% by weight, and more preferably from about 0.5% to about 4% by weight, based on the solids content of the hydrophilic copolymer.

[0050] The surfactant may include a nonionic surfactant, an ionic surfactant such as an anionic surfactant, or a combination thereof.

[0051] Practical examples of suitable nonionic surfactants include, but are not limited to, polyhydroxyl alcohol fatty acid esters, alcohol ethoxylates, polyoxyethylene lauryl ether, polyoxyethylene monostearate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, ethoxylated castor oils, such as polyethylene glycol castor oil, and others. In embodiments, the nonionic surfactant is selected from polyhydroxyl alcohol fatty acid esters, such as esters formed from polyhydroxyl alcohols having about 2 to 20 hydroxyl groups, such as sugars, ethylene glycol, glycerin, pentaerythritol, sorbitol, and others, and fatty acids having about 1 to about 30 carbon atoms. In a preferred embodiment, the nonionic surfactant is selected from sugar fatty acid esters, such as monoesters, diesters, or triesters of sucrose or glucose with higher fatty acids, such as lauric acid, stearic acid, oleic acid, and palmitic acid, or lower fatty acids, such as acetic acid and isobutyric acid. In one embodiment, a nonionic surfactant is used that comprises a sucrose fatty acid ester selected from sucrose monolaurate, sucrose dilaurate, sucrose monostearate, or sucrose distearate.

[0052] Practical examples of suitable anionic surfactants include, but are not limited to, alkali metal sulfonate, sulfate, phosphate, and carboxylate surfactants. Specific examples of these surfactants include alkali metal sulfonates such as sulfosuccinates, glycerin fatty acid ester sulfonates, and sulfonates of monohydric alcohol esters; alkali metal salts of sulfonated aromatic hydrocarbons such as sodium dodecylbenzenesulfonate and sodium α-naphthalenesulfonate; sodium lauryl sulfates such as sodium cetostearyl sulfate, triethanolamine lauryl sulfate, and sodium lauryl ether sulfate; phosphates such as potassium cetyl phosphate; and carboxylates such as alkali metal salts of carboxylic acids having about 6 to 30 carbon atoms. In embodiments, the anionic surfactant is selected from sulfosuccinates, such as alkali metal (e.g., sodium or potassium) sulfonates of succinic acid monoesters or diesters, preferably sulfonates of succinic acid monoesters or diesters with fatty acid alcohols having about 3 to 30 carbon atoms, preferably about 4 to 25 carbon atoms, and more preferably about 6 to 20 carbon atoms. Practical examples of sulfosuccinate surfactants include, but are not limited to, sodium sulfonates of succinic acid monoesters, such as disodium lauryl sulfosuccinate, and sodium sulfonates of succinic acid diesters, such as dioctyl sodium sulfosuccinate. In embodiments, anionic surfactants are used, including sulfosuccinate surfactants, such as dioctyl sodium sulfosuccinate.

[0053] The surfactant may be present in the coating composition of the present invention in an amount ranging from about 1% to about 25% by weight, preferably from about 3% to about 20% by weight, and more preferably from about 5% to about 15% by weight, based on the solids content of the hydrophilic copolymer.

[0054] The coating composition may contain one or more solvents for dissolving or dispersing various components. Practical examples of solvents include, but are not limited to, hydrocarbon solvents, alcohol solvents, ether solvents, amide solvents, ester solvents, and halohydrocarbon solvents. Examples of hydrocarbon solvents include n-hexane, n-pentane, benzene, toluene, and xylene. Examples of alcohol solvents include C1-C4 alcohols, such as methanol, ethanol, propanol, isopropanol (IPA), n-butanol, and t-butanol. Examples of ether solvents include diethyl ether, diisopropyl ether, methyl t-butyl ether, tetrahydrofuran (THF), cyclopentyl methyl ether, dimethoxyethane, and 1,4-dioxane. Examples of amide solvents include dimethylformamide (DMF), dimethylacetamide (DMAc), and N-methyl-2-pyrrolidone (NMP). Examples of ester solvents include C1-C4 alkyl esters of acetic acid, such as ethyl acetate. Examples of halohydrocarbon solvents include chloroform, methylene chloride, and 1,2-dichloroethane. These solvents may be used alone or in combination of two or more thereof. In some embodiments, C1-C5 alcohol solvents, such as methanol, ethanol, propanol, isopropanol (IPA), n-butanol, t-butanol, methoxypropanol, and methoxybutanol, are used in coating compositions, particularly curable coating compositions.

[0055] The solvent may be present in the coating composition of the present invention in an amount sufficient to disperse the various components, which may typically range from about 10% to about 95% by weight, preferably from about 15% to about 80% by weight, and more preferably from about 20% to about 75% by weight, based on the total weight of the coating composition.

[0056] A crosslinking agent may be optionally used. If used, the crosslinking agent is preferably selected from alkoxysilane compounds. The alkoxysilane compound may be any of trialkylmonoalkoxysilanes, dialkyldialkoxysilanes, alkyltrialkoxysilanes, and tetraalkoxysilanes (also known as tetraalkylorthosilicates), with alkyltrialkoxysilanes and tetraalkoxysilanes being preferred. Examples of trialkylmonoalkoxysilanes include trimethylmethoxysilane, trimethylethoxysilane, triethylethoxysilane, triethylmethoxysilane, and mixtures thereof. Examples of dialkyldialkoxysilanes include dimethyldimethoxysilane, diethyldiethoxysilane, diethyldimethoxysilane, and mixtures thereof. Examples of alkyltrialkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, and mixtures thereof. Examples of tetraalkoxysilanes (ie, tetraalkylorthosilicates) include tetramethoxysilane, dimethoxydiethoxysilane, tetraethoxysilane, methoxytriethoxysilane, tetrapropoxysilane, and mixtures thereof.

[0057] The crosslinking agent may be present in an amount of at most about 10% by weight, preferably no more than about 5% by weight, and more preferably no more than about 1% by weight, based on the solids content of the hydrophilic copolymer. In embodiments, the crosslinkable coating composition of the present invention can be cured to form a cured composition in the absence of any crosslinking agent. In most conventional curable coating compositions, a crosslinking agent is generally required to cause the coating to cure. However, crosslinking agents such as alkoxysilane compounds can undergo self-hydrolysis or condensation, resulting in undesirable side reactions and by-products. Therefore, it is advantageous to avoid the use of such crosslinking agents.

[0058] The coating composition may further contain optional additives, such as adhesion promoters and leveling agents known for use in the coating field, depending on the intended purpose of the composition. The adhesion promoter may generally be selected by one skilled in the art depending on the substrate to be coated. For example, if the substrate to be coated is a polymer substrate, the adhesion promoter may be a (meth)acrylate polymer, such as a (meth)acrylate polyol copolymer, functionalized with a hydroxyl group, a carboxyl group, or an acid anhydride group; and if the substrate to be coated is a glass substrate, the adhesion promoter may be an alkoxysilane functionalized with an amino group, a vinyl group, or a thiol group. Practical examples of commercially available additives include, but are not limited to, Joncryl acrylate from BASF as an adhesion promoter for polymer substrates. 登録商標 587, Momentive Performance Materials' Silquest as an adhesion promoter for glass substrates TM A1110 Silane and Silquest TM A1100 silane and Momentive Performance Materials' CoatOSil as a leveling agent 登録商標 Coating additives included.

[0059] In embodiments, the coating composition may be present in the form of a two-package or multi-package coating system comprising at least a first-package composition and a second-package composition, where the first-package composition comprises the hydrophilic copolymer; and the second-package composition comprises the catalyst. The multi-package coating system may further comprise a third-package composition comprising one or more additional components selected from any additive conventionally used in coating compositions, such as surfactants, solvents, crosslinking agents, adhesion promoters, or leveling agents. The additional components may also be present in the first-package composition and / or the second-package composition, provided that they do not react with the component(s) already present in the packaged compositions. In embodiments, the coating composition may be present in the form of a two-package coating system comprising a first-package composition containing the hydrophilic copolymer and the crosslinking agent; and a second-package composition containing the catalyst, with the remaining components being present in the first-package composition, the second-package composition, or both. In one embodiment, the coating composition is present in the form of a two-package coating system, comprising a first package composition containing a hydrophilic copolymer, a crosslinker, and a solvent; and a second package composition containing a catalyst, a surfactant, an adhesion promoter, and optionally a solvent that may be different from the solvent of the first package composition. In another embodiment, the coating composition is present in the form of a two-package coating system, comprising a first package composition containing a hydrophilic copolymer, a crosslinker, an adhesion promoter, and a solvent; and a second package composition containing a catalyst, a surfactant, and optionally a solvent that may be different from the solvent of the first package composition. In a further embodiment, the coating composition is present in the form of a two-package coating system, comprising a first package composition containing a hydrophilic copolymer, a crosslinker, an adhesion promoter, a surfactant, and a solvent; and a second package composition containing a catalyst and optionally a solvent that may be different from the solvent of the first package composition. From the standpoint of storage stability, the coating composition is preferably present in the form of a two-package or multi-package coating system.Each of the components may be present in the two-pack or multi-pack coating system in amounts similar to those described above for the coating composition.

[0060] The coating compositions of the present application may be prepared by simply blending the hydrophilic copolymer with the various components in the desired ratios. These components may be dispersed or dissolved in a solvent prior to blending, or may be mixed together directly in a solvent. The crosslinkable composition may optionally be diluted to a solids content appropriate for the coating method adapted to apply the coating composition to a substrate.

[0061] In a further embodiment, the present invention provides an article comprising a substrate, wherein at least a portion of a surface of the substrate comprises a coating formed from a coating composition according to the above embodiment.

[0062] Practical examples of suitable substrates include, but are not limited to, polymeric substrates such as (meth)acrylic polymers, e.g., poly(methyl methacrylate), polycarbonate, polyesters, e.g., polyethylene terephthalate and polybutylene terephthalate, polyamides, polyimides, acrylonitrile-styrene copolymers, styrene-acrylonitrile-butadiene terpolymers, polyvinyl chloride, polyethylene, or any combination of two or more of these, and any other suitable substrate, such as glass.

[0063] The composition may be applied to a substrate by conventional techniques, such as brush coating, spray coating, dip coating, roller coating, or flow coating. The coating amount or amount of coating may be such that the coating has a dry film thickness ranging from about 0.5 μm to about 30 μm, preferably from about 1 μm to about 25 μm, more preferably from about 2 μm to about 20 μm, and even more preferably from about 3 μm to about 15 μm, for example, from about 4 μm to about 12 μm or from about 5 μm to about 10 μm.

[0064] The coating composition may be thermally or UV cured following application of the composition to a substrate. In embodiments, the wet film of the coating composition on the substrate may be optionally flashed off before being thermally cured in air or an inert atmosphere by exposure to elevated temperatures, for example, from about 40°C to about 200°C, preferably from about 50°C to about 180°C, and more preferably from about 60°C to about 150°C. In another embodiment, the wet film of the coating composition on the substrate may be cured by exposure to suitable radiation, such as ultraviolet radiation. Curing times may vary, for example, from about 0.5 hours to about 4 hours, preferably from about 1 hour to about 3 hours, depending on the composition of the wet film.

[0065] The coating film formed from the coating composition of the present application can substantially limit or prevent fogging of the substrate. In an embodiment, the coating film has strong adhesion to the substrate and exhibits good scratch resistance. In one preferred embodiment, the coating film can maintain its anti-fogging properties and scratch resistance for a long period of time. Therefore, substrates with such anti-fogging coatings can be used in various applications, including, but not limited to, safety glass, protective shields, automobile headlights, windshields, eyeglasses, goggles, mirrors, transparent containers, windows, or camera lenses.

[0066] In yet another aspect, the present invention provides the use of a hydrophilic copolymer, coating composition, or cured composition according to any of the above-described aspects to impart anti-fog and scratch resistance to a substrate or article. Substrates herein include, but are not limited to, polymeric substrates, such as (meth)acrylic polymers, e.g., poly(methyl methacrylate), polycarbonate, polyesters, e.g., polyethylene terephthalate and polybutylene terephthalate, polyamides, polyimides, acrylonitrile-styrene copolymers, styrene-acrylonitrile-butadiene terpolymers, polyvinyl chloride, polyethylene, or any combination of two or more thereof, and any other suitable substrate, such as glass. Articles herein include, but are not limited to, safety glass, protective shields, automobile headlights, windshields, eyeglasses, goggles, mirrors, transparent containers, windows, or camera lenses. In a preferred embodiment, the anti-fog properties of the substrate or article can be maintained after immersion in water at 40°C for 1 hour, followed by drying at 80°C for 30 minutes. [Example]

[0067] The present invention will be described more specifically with reference to examples, but these examples should not be construed as limiting the scope of the present invention. In the following description, "parts" and "%" refer to "parts by weight" and "% by weight" unless otherwise specified.

[0068] material All alkoxysilane compounds were obtained from Momentive Performance Materials. OT-70 (dioctyl sodium sulfosuccinate) was obtained from Solvay. L-1695 (sucrose monolaurate) was obtained from Mitsubishi Chemical. Joncryl 587 is an adhesion promoter from BASF.

[0069] General Procedure for Preparing Hydrophilic Copolymers All reactants were dried to a moisture level of less than 200 ppm before use. A 250 mL four-neck flask was dried and equipped with a mechanical stirrer, a condenser, a nitrogen gas conduit, and a dropping funnel. Then, 40 parts of dimethylacetamide (DMAc) was charged at room temperature. Separately, a mixed solution was prepared by dissolving the reactants and 0.4 parts of 2,2'-azobis-(2,4-dimethylvaleronitrile) (ABVN) as an initiator in 40 parts of DMAc. The flask was gradually heated to 65°C under a N2 atmosphere, and the mixed solution was added through the dropping funnel over a period of 3 hours. The resulting mixture was allowed to react at 65°C for an additional 5 hours and then cooled to room temperature. Finally, a copolymer dispersion was obtained.

[0070] General Procedure for Preparing Coatings on Polycarbonate Substrates The prepared copolymer dispersion was mixed with methyltrimethoxysilane (MTMS) as a crosslinker (if used), a catalyst solution (20% tetra-n-butylammonium acetate (TBAA) in isopropanol), and a surfactant solution (70% OT-70 in isopropanol and 10% L-1695 in propylene glycol monomethyl ether) in isopropanol (IPA) as a solvent to obtain a coating solution with a solid content of 15 wt %.

[0071] A polycarbonate substrate (PC grade: 2467) was wiped with isopropanol and dried with deionized air. The coating solution prepared above was then applied to the dried polycarbonate substrate surface by flow coating and allowed to flash off at room temperature for 5 minutes. The polycarbonate substrate was then cured in an oven at 120°C for 2 hours and then cooled to room temperature.

[0072] Performance evaluation The coated polycarbonate substrates were then tested for initial properties and properties after a water immersion procedure, which involved immersing the coated polycarbonate substrates in water at 40°C for 1 hour, followed by drying at 80°C for 30 minutes, and then cooling to room temperature.

[0073] Properties tested included the appearance of the coating as observed by the naked eye, the thickness of the dried coating, the adhesion of the coating to the substrate, and anti-fog properties. The coatings were also tested for scratch resistance. Further details of each test are provided below. Thickness is reported as a range because the thickness of the coating from top to bottom varies.

[0074] exterior The coating was visually inspected with the naked eye and given an "OK" result if the dried film was clear and no peeling occurred.

[0075] Adhesion Test Adhesion testing was performed according to ASTM D3359, Method B. A grid pattern with 25 2 mm x 2 mm squares was created by cutting six times in each direction of the coating with a knife. Approximately 4 inches (about 10 cm) of adhesive tape (3M810) was applied over the grid pattern, and the tape was peeled from the coating at an angle as close to 180° as possible within 90 ± 30 seconds of application. The grid pattern was then visually inspected for the presence of peeled squares. A rating of 5B to 0B was used, with 5B indicating the best adhesion, with none of the squares affected by the peel test. If less than 5% of the total square area was affected by the peel test, the specimen was rated 4B. 3B, 2B, and 1B represent peels of 5-15%, 15-35%, and 35-65%, respectively. Peeling of more than 65% was rated 0B.

[0076] Anti-Fog Test The anti-fogging tests included Anti-fogging Test 1 (AF-1) and Anti-fogging Test 2 (AF-2), which were performed as follows.

[0077] For AF-1, the coated specimen was held 5 cm above the water bath surface in a container held in a heating jacket maintained at 60°C. The specimen covered the opening of the container, with the coated surface facing downward so that the coated surface was exposed to steam from the water bath for 90 seconds. The formation of a water layer on the specimen (if any) was visually observed, and the time when cloudiness appeared was recorded as the result for AF-1.

[0078] For AF-2, the coated specimen was held 4 cm above the opening of a vessel containing a water bath maintained at 60°C. The water level was 10 cm below the vessel opening. Thus, the coated surface of the specimen was facing downward toward the water surface, with a total distance of 14 cm between the coated surface and the water surface. The coated surface was exposed to steam from the water bath for 90 seconds. The time when clouding occurred was recorded as the result for AF-2.

[0079] Scratch resistance test The test was carried out by scratching the coating with steel wool (0000#) at 14 Kpa for 11 cycles. The haze value was measured before and after scratching, and the increase in haze value was reported as the scratch resistance result.

[0080] Examples 1 to 9 Hydrophilic copolymers were prepared using the reactants shown in Table 1 below. Each prepared copolymer dispersion was mixed with a catalyst solution, a surfactant solution, a solvent, an MTMS crosslinker, and an adhesion promoter in the amounts shown in Table 1 to obtain a coating composition. Each coating composition was applied to a polycarbonate substrate and tested for initial properties and properties after water immersion using the procedures described above. The results are shown in Table 1 below.

[0081] The results in Table 1 show that all coatings according to the present invention exhibit initial anti-fog properties and strong adhesion to the substrate, and that by adjusting the copolymer composition, long-term anti-fog properties can be obtained.

[0082] Examples 10 to 17 Hydrophilic copolymers were prepared using the reactants shown in Table 2 below. Each prepared copolymer dispersion was mixed with a catalyst solution, solvent, and surfactant solution in the amounts shown in Table 2 to obtain a coating composition. No crosslinker was used. Each coating composition was applied to a polycarbonate substrate and tested for initial properties and properties after water immersion using the procedures described above. The results are shown in Table 2 below.

[0083] From Table 2, it can be seen that an anti-fog coating with good scratch resistance and adhesion was formed without using a crosslinker.

[0084] [Table 1]

[0085] [Table 2]

[0086] Examples 18 to 22 Following the general procedure for preparing hydrophilic copolymers, hydrophilic copolymers were prepared using the reactants shown below in Table 3. Each of the prepared copolymer dispersions (40% solids) was mixed with 0.4 parts of catalyst solution, 22.5 parts of solvent, and surfactant solution (0.75 parts of OT-70 solution and 2.55 parts of L-1695 solution) to obtain coating compositions.

[0087] Each coating composition was applied to a polycarbonate substrate and tested for initial properties and properties after water immersion using the procedures described above, with the results shown in Table 3 below.

[0088] From Table 3, it can be seen that hydrophilic copolymers formed from acrylamide compounds having tertiary amino groups (e.g., N,N-dimethylacrylamide or N,N-diethylacrylamide) demonstrate coatings with improved long-term anti-fog properties compared to corresponding copolymers formed from acrylamide compounds having primary amino groups (e.g., acrylamide) or acrylamide compounds having secondary amino groups (e.g., Nt-butylacrylamide or N-isopropylacrylamide).

[0089] [Table 3]

[0090] Examples 23 to 24 Following the general procedure for preparing hydrophilic copolymers, hydrophilic copolymers were prepared using the reactants shown below in Table 4. Each of the prepared copolymer dispersions was mixed with a catalyst solution, a surfactant solution, a solvent, an MTMS crosslinker, and an adhesion promoter (aminopropyltrimethoxysilane or aminopropyltriethoxysilane) in the amounts shown in Table 4 to obtain coating compositions.

[0091] Each coating composition was applied to a glass plate and cured at 125°C for 1 hour. The resulting coatings on the glass plates were tested for initial properties and properties after water immersion using the procedures described above. The results are shown in Table 4 below.

[0092] [Table 4]

[0093] Examples 25 and 26 Two samples in the form of a two-pack coating system were prepared and stored prior to use. The polymer dispersion prepared in Example 1, methyltrimethoxysilane (MTMS), tetra-n-butylammonium acetate (TBAA), OT-70 and L-1695 as surfactants, Joncryl 587 as an adhesion promoter, and propylene glycol monomethyl ether (PGME) and isopropanol (IPA) as solvents were stored in two pots (Pot A and Pot B) as shown in Table 5 below. The numbers in parentheses following each compound indicate the amount of the corresponding component.

[0094] The two pots in each of Examples 25 and 26 were then placed in a 50°C oven. The appearance of the contents of each pot remained unchanged after four weeks. The contents of Pots A and B were then mixed together and coated onto a polycarbonate substrate using the general procedure for preparing coatings on polycarbonate substrates described above.

[0095] [Table 5]

[0096] While the present disclosure has been described with reference to preferred embodiments, those skilled in the art will recognize that various changes can be made and equivalents substituted for elements thereof without departing from the scope of the disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings disclosed without departing from the essential scope thereof. Therefore, it is not intended that the present disclosure be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this disclosure, but rather, the disclosure is intended to include all embodiments falling within the scope of the appended claims.

Claims

1. 1. A hydrophilic copolymer comprising: A first repeating unit represented by general formula (1): 【Transformation 7】 A second repeating unit represented by general formula (2): 【Transformation 8】 and optionally A third repeating unit represented by general formula (3): 【Chemistry 9】 wherein R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , R ８ and R ９ are each independently selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally containing heteroatoms; X is -(L Ｆ ) ｍ -L １ -Si(OR １１ ) ａ (R １２ ) ３－ａ a monovalent siloxy-containing group represented by Y is -(L Ｆ ) ｍ - (L ２ ) ｎ -C(O)-N(R ２１ ) (R ２２ ) a monovalent hydrophilic group represented by Z is -(L Ｆ ) ｍ - (L ３ ) ｎ -C(O)-L ４ -R ３１ is a monovalent organic group represented by where L Ｆ each independently represents a divalent organic group selected from —O—, —N(R)—, —C(O)—, —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—, where R represents a hydrogen atom or an alkyl group having from 1 to about 6 carbon atoms; L １ , L ２ and L ３ each independently represents a substituted or unsubstituted divalent hydrocarbon group having from 1 to about 20 carbon atoms and optionally containing heteroatoms; L ４ is selected from an oxygen atom or a sulfur atom; R １１ are each independently an alkyl group having from 1 to about 12 carbon atoms; R １２ each independently represents a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally containing heteroatoms; R ２１ and R ２２ are each independently selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally containing heteroatoms; R ３１ are each independently selected from a hydrogen atom or a monovalent hydrocarbon group having from 1 to about 16 carbon atoms and optionally having one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl; each of the subscripts m and n is independently 0 or 1; and The subscript a is 1, 2 or 3.

2. L Ｆ is independently selected from —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—; preferably —C(O)O— or —C(O)N(R)—.

3. X is -L １ -Si(OR １１ ) ａ (R １２ ) ３－ａ or -L Ｆ -L １ -Si(OR １１ ) ａ (R １２ ) ３－ａ , preferably -L Ｆ -L １ -Si(OR １１ ) ａ (R １２ ) ３－ａ where L Ｆ is selected from —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—; L １ is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups; R １１ are each independently an alkyl group having from 1 to about 8 carbon atoms; R １２ are each independently selected from an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; and a is 2 or 3.

4. Y is: -L Ｆ -L ２ -C(O)-N(R ２１ )(R ２２ ) (Y1) Here, L Ｆ is selected from —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—; L ２ is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups; R ２１ and R ２２ are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; -L Ｆ -C(O)-N(R ２１ )(R ２２ ) (Y2) Here, L Ｆ is selected from —O—, —N(R)—, —C(O)—, —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—; R ２１ and R ２２ are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; -L ２ -C(O)-N(R ２１ )(R ２２ ) (Y3) Here, L ２ is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups; R ２１ and R ２２ are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; or -C(O)-N(R ２１ )(R ２２ ) (Y4) Here, R ２１ and R ２２ are each independently selected from a hydrogen atom, an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms; Preferably, Y is selected from the above formula (Y1), (Y2), (Y3) or (Y4), wherein R ２１ and R ２２ are each independently selected from an alkyl group having from 1 to about 12 carbon atoms, an aryl group having from about 6 to about 16 carbon atoms, an aralkyl group having from about 7 to about 16 carbon atoms, or an alkaryl group having from about 7 to about 16 carbon atoms.

5. The copolymer includes a third repeat unit, wherein the monovalent organic group Z is: -L Ｆ -L ３ -C(O)-O-R ３１ or -L Ｆ -L ３ -C(O)-S-R ３１ , where L Ｆ is selected from —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—; L ３ is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups; and R ３１ is a hydrogen atom or optionally substituted with one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl groups, and is selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms; -L Ｆ -C(O)-O-R ３１ or -L Ｆ -C(O)-S-R ３１ , where L Ｆ is selected from —O—, —N(R)—, —C(O)—, —OC(O)—, —C(O)O—, —N(R)C(O)—, —C(O)N(R)—, —N(R)C(O)O—, or —OC(O)N(R)—; and R ３１ is a hydrogen atom or optionally substituted with one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl groups, and is selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms; -L ３ -C(O)-O-R ３１ or -L ３ -C(O)-S-R ３１ , where L ３ is a divalent hydrocarbon radical having 1 to about 20 carbon atoms, optionally containing one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, amide, or carboxyl groups; and R ３１ is a hydrogen atom or optionally substituted with one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl groups, and is selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms; or -C(O)-O-R ３１ or -C(O)-S-R ３１ , where R ３１ is a hydrogen atom or optionally substituted with one or more functional groups selected from hydroxyl, mercapto, ether, ester, amine, or carboxyl groups, and is selected from an alkyl group having 1 to about 12 carbon atoms, an aryl group having about 6 to about 16 carbon atoms, an aralkyl group having about 7 to about 16 carbon atoms, or an alkaryl group having about 7 to about 16 carbon atoms.

5. The hydrophilic copolymer of claim 1, wherein the copolymer is selected from the group consisting of:

6. 6. The hydrophilic copolymer of any one of claims 1 to 5, wherein the first repeat unit represents from about 1 mol% to about 40 mol%, preferably from about 2 mol% to about 35 mol%, and more preferably from about 5 mol% to about 30 mol% of the hydrophilic copolymer; the second repeat unit represents from about 25 mol% to about 85 mol%, preferably from about 30 mol% to about 80 mol%, and more preferably from about 35 mol% to about 75 mol% of the hydrophilic copolymer; and the third repeat unit represents from about 0 mol% to about 50 mol%, preferably from about 5 mol% to about 45 mol%, and more preferably from about 10 mol% to about 40 mol% of the hydrophilic copolymer.

7. 7. The hydrophilic copolymer of any one of claims 1 to 6, wherein the copolymer is a copolymer of the first repeat unit and the second repeat unit; or a terpolymer of the first repeat unit, the second repeat unit, and the third repeat unit.

8. 8. The hydrophilic copolymer of any one of claims 1 to 7, wherein the copolymer has a weight average molecular weight (Mw) of about 50,000 to 500,000, preferably about 60,000 to 400,000, and more preferably 70,000 to 300,000; and a number average molecular weight (Mn) of about 5,000 to 120,000, preferably about 6,000 to 90,000, and more preferably 7,000 to 600,000, as measured by gel permeation chromatography (GPC) using polystyrene standards.

9. Formula C(R １ ) (R ２ ) = C(R ３ ) X, a first monomer of formula C(R ４ ) (R ５ ) = C(R ６ ) Y, and optionally a second monomer of formula C(R ７ ) (R ８ ) = C(R ９ ) a third monomer of Z, where R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , R ８ , R ９ 9. A process for preparing the hydrophilic copolymer of any one of claims 1 to 8, wherein X, Y and Z are defined as in claim 1 undergo radical polymerization in the presence of an initiator selected from an azo initiator, an inorganic peroxide initiator, or an organic peroxide initiator, preferably an azo initiator, more preferably 2,2'-azobis-(2-methylpropionitrile), 2,2'-azobis-(2-methylbutanenitrile), or 2,2'-azobis-(2,4-dimethylvaleronitrile).

10. 10. A coating composition comprising the hydrophilic copolymer of any one of claims 1 to 8 or prepared by the method of claim 9.

11. the composition further comprises a catalyst, a surfactant, a solvent, a crosslinker, an adhesion promoter, or any combination of two or more thereof; Preferably, the catalyst comprises a tetraalkylammonium carboxylate compound; Preferably, the surfactant comprises a nonionic surfactant, preferably a polyhydroxy alcohol fatty acid ester, more preferably a sugar fatty acid ester; an ionic surfactant, preferably an alkali metal sulfonate of sulfosuccinic acid, more preferably a succinic acid monoester or diester; or a combination thereof; and Preferably, the crosslinker is selected from trialkylmonoalkoxysilanes, dialkyldialkoxysilanes, alkyltrialkoxysilanes, and tetraalkoxysilanes. The coating composition of claim 10.

12. 12. The coating composition of claim 10 or 11, wherein the hydrophilic copolymer is present in an amount of from about 30% to about 99.9% by weight based on the total solids content of the composition.

13. 10. A two-pack or multi-pack coating system comprising at least a first package composition and a second package composition, and optionally a third package composition, wherein the first package composition comprises the hydrophilic copolymer of any one of claims 1 to 8 or the hydrophilic copolymer prepared by the method of claim 9; and the second package composition comprises a catalyst.

14. 14. The two-pack or multi-pack coating system of claim 13, further comprising a surfactant, a solvent, a crosslinker which is preferably an alkoxysilane compound, an adhesion promoter, or any combination of two or more thereof, any one of which may be present in at least one of the first package composition, the second package composition, and, if present, the third package composition.

15. 10. A method for preparing a coating composition comprising blending a hydrophilic copolymer of any one of claims 1 to 8 or a hydrophilic copolymer prepared by the method of claim 9 with a catalyst, and optionally a component selected from a surfactant, a solvent, a crosslinker, an adhesion promoter, or any combination of two or more of these.

16. 16. A cured composition formed by curing the coating composition of any one of claims 10 to 12, with or without a crosslinking agent; or by mixing a first package composition and a second package composition as defined in claim 13 or 14, followed by curing.

17. 15. An article comprising a substrate, at least a portion of a surface of the substrate comprising a coating formed from the coating composition of any one of claims 10 to 12, or from the two-pack or multi-pack coating system of claims 13 or 14, preferably the article is selected from safety glass, a protective shield, an automobile headlight, a windshield, eyeglasses, goggles, a mirror, a transparent container, a window, or a camera lens.

18. 18. The article of claim 17, wherein the substrate is selected from glass, a (meth)acrylic polymer, a polycarbonate, polyethylene terephthalate, polybutylene terephthalate, a polyamide, a polyimide, an acrylonitrile-styrene copolymer, a styrene-acrylonitrile-butadiene terpolymer, polyvinyl chloride, polyethylene, or a combination thereof.

19. 13. A method for imparting anti-fog and / or scratch resistance to a substrate or article, comprising applying to the substrate or article a hydrophilic copolymer of any one of claims 1 to 8, a hydrophilic copolymer prepared by the method of claim 9, a coating composition of any one of claims 10 to 12, a two-pack or multi-pack coating system of claim 13 or 14, or a cured composition of claim 16.

Images