WO2012091161A2

WO2012091161A2 - Curable composition and article having a cured layer from the composition

Info

Publication number: WO2012091161A2
Application number: PCT/JP2011/080577
Authority: WO
Inventors: Akito Hayashi; Tomohiro Iimura
Original assignee: Dow Corning Toray Co., Ltd.
Priority date: 2010-12-28
Filing date: 2011-12-26
Publication date: 2012-07-05
Also published as: WO2012091161A3; JP6067206B2; JP2012136676A

Abstract

This invention relates to a curable composition that contains (A) a copolymer that contains the hydroxyl group and a group having a prescribed carbosiloxane dendrimer structure and (B) an isocyanate compound, and article that bears a cured layer provided by the curable composition. The curable composition forms a high-hardness cured layer that exhibits an excellent uniformity, transparency, solvent resistance, staining/soiling resistance, and water repellency.

Description

DESCRIPTION Title of Invention CURABLE COMPOS ITI ON AND ARTICLE HAVING A CURED LAYER FROM THE

COMPOS ITION

Technical Field

[0001 ] Priority is claimed on Japanese Patent Application No. 2010-291658, filed on December 28, 2010, the content of which is incorporated herein by reference.

[0002] The present invention relates to a curable composition that forms a very hard cured layer that exhibits an excellent uniformity, transparency, solvent resistance, staining/soiling resistance, and water repellency. The invention of the present application further relates to an article that has a cured layer provided by the cure of this curable composition.

Background Art

[0003] Silicone-modified vinyl resins comprising a vinyl polymer having a straight chain polyorganosiloxane group in side chain position are known. These resins are obtained by the copolymerization of a vinyl ic compound with a straight chain

polyorganosi loxane having a polymerizable group at one terminal (Patent Document 1 ). Due to the effect of the polyorganosiloxane group in side chain position, these silicone- modified vinyl resins exhibit an excellent staining/soiling resistance and water repellency and are incorporated in diverse coating agents in order to impart these functionalities.

[0004] However, when the polyorganosiloxane has a high molecular weight, these resins exhibit a substantially diminished compatibi lity with a variety of materials and as a result problems have appeared when they are incorporated in curable systems. Thus, a cloudy white appearance has occurred; the staining/soiling resistance and water repellency have been inadequate; and the hardness has undergone a substantial decline. It has therefore been quite difficult to use these resins in applications where the articles are required to exhibit staining/soiling resistance, hardness, and durabil ity, and by

themselves these resins can only be used in a limited range of applications.

[0005]

[Patent Document 1 ] JP 61 -078806 A Disclosure of Invention

Technical Problems to be Solved

[0006] An object of the present invention is to provide a curable composition that gives a cured layer that has a high hardness and exhibits an excellent uniformity, transparency, solvent resistance, staining/soil ing resistance, and water repellency. A further object of the present invention is to provide an article that has a cured layer that exhibits these same properties.

Solution to Problems

[0007] As a result of intensive investigations in order to solve the problems identified above, the present inventors discovered that a high-hardness curable composition that exhibits an excellent transparency, staining/soiling resistance, and water repellency is obtained by using— as the base component of an isocyanate/melamine-curing type curable composition that is reactive with the hydroxyl group— a copolymer (A) that has the hydroxyl group in its molecule as a functional group that is reactive with resins and that also has in its molecule a special carbosiloxane dendrimer structure that provides properties such as a high water repellency and so forth. The present invention was achieved based on this discovery. [0008] Thus, the problems identified for the present invention are solved by a curable composition comprising (A) a copolymer that contains in its molecule the hydroxyl group and a special carbosiloxane dendrimer structure and (B) at least one curing agent selected from the group consisting of isocyanate compounds and melamine compounds. The problems identified for the present invention are also solved by an article that has a cured layer provided by the cure of this curable composition.

[0009] Thus, the aforementioned objects can be achieved by

" [ 1 ] A curable composition comprising

(A) a copolymer that contains in the molecule a hydroxyl group and a group having a carbosi loxane dendrimer structure given by the following formula ( 1 ) and

(B) at least one curing agent selected from the group consisting of isocyanate compounds and melamine compounds

wherein

Z is a divalent organic group, p is 0 or 1 ,

1 2

R and R are each independently a C J . J O alkyl group, an aryl group, or an aralkyl and

L ¹ is a silylalkyl group represented by the following structural formula (2) when i =

wherein

Z and p are defined as above,

1 2

R and R are defined as above, i is an integer from 1 to 1 0 that indicates the total number of generations of the silylalkyi group,

L^{I+ 1} is a group selected from the group consisting of the hydrogen atom, C J . J O alkyl groups, aryl groups, aralkyl groups, and the aforementioned silylalkyi group, wherein when i = c with c being an integer from 1 to 1 0 that indicates the generation of the silylalkyi group, is the hydrogen atom, a C \ . \ Q alkyl group, an aryl group, or an aralkyl group, and when i < c, is the aforementioned silylalkyi group, and a' is an integer from 0 to 3. [0010]

[2] The curable composition according to [ 1 ], wherein the copolymer (A) is a copolymer provided by the copolymerization of at least one or more selections from each of the following unsaturated monomers (a l ) and (a2):

(a l ) unsaturated monomers that have at least one hydroxyl group in the molecule and (a2) radically polymerizable unsaturated monomers given by the fol lowing formula ( )

wherein

Y is a group that contains radically polymerizable unsaturation and

Z, p, R¹ , R², L ¹ , and a' are as defined above.

[0011]

[3] The curable composition according to [2], wherein the group Y that contains radically polymerizable unsaturation in the radically polymerizable unsaturated monomer given by formula ( Γ) is a group selected from the group consisting of acryl ic group- containing organic groups and methacrylic group-containing organic groups given by the following general formulas

wherein the hydrogen atom or a methyl group and

R is a C i _ ] o alkylene group

wherein

R and R are defined as above, alkenylaryl group-containing organic groups given by the fol lowing general formula

wherein

R⁶ is the hydrogen atom or a methyl group,

7

R is a C J . J O alkyl group,

g

R is a C j _ i o alkylene group, b is an integer from 0 to 4, and c is 0 or 1 , and 2- I O alkenyl groups.

[0012]

[4] The curable composition according to [2], wherein the copolymer (A) is obtained by the copolymerization additionally of at least one or more (a3) unsaturated monomer that does not contain the hydroxyl group in the molecule.

[5] The curable composition according to [3] or [4] , characterized in that the copolymer (A) is a copolymer provided by the copolymerization of the aforementioned unsaturated monomers (al ) and (a2) and optional (a3) as constituent units thereof, wherein their mass ratios, taking the sum of the masses of the unsaturated monomers (a l ) to (a3) constituting the copolymer to be 1 00 mass parts, are in the range (a l ) : (a2) : (a3) = 0.5 - 50.0 : 0.5 - 50.0 : 0 - 99.0. [6] The curable composition according to any one of [ 1 ] to [5], wherein the unsaturated monomer (al ) constituting the copolymer (A) is at least one unsaturated monomer containing the hydroxyl group and selected from the group consisting of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate.

[7] The curable composition according to [ 1 ], wherein the curing agent is at least one (B l ) isocyanate compound.

[8] The curable composition according to [ 1 ] or [7], wherein the curing agent is at least one (B l -2) polyisocyanate compound. [9] The curable composition according to [ 1 ] to [8], wherein the molar equivalent for the NCO group in the curing agent (B) is in the range from 0.1 to 2.0 per 1 equivalent of the hydroxyl group in the copolymer (A). [0013]

[ 10] An article having a 0. 1 - to 10 μηι-thick cured layer provided by the cure of the curable composition according to any 1 of [ 1 ] to [9] .

[ 1 1 ] The article according to [ 10], that is a plate-shaped or sheet-shaped member.".

Advantageous Effects of Invention

[0014] The present invention provides a curable composition that gives a high-hardness cured layer that exhibits an excellent uniformity, transparency, solvent resistance, staining/soiling resistance, and water repellency. The present invention also provides an article that has a cured layer that exhibits the aforementioned properties.

Description of the Invention

[0015] The curable composition according to the present invention and the article according to the present invention having a cured layer provided by this composition are described in detail herebelow.

[0016] The curable composition according to the product of the present invention characteristically contains, as its base component, a copolymer (A) that contains in its molecule a hydroxyl group and a specific carbosiloxane dendrimer structure. This copolymer (A) is a copolymer obtained by the copolymerization of an unsaturated monomer having the hydroxyl group in the molecule and an unsaturated monomer having the carbosiloxane dendrimer structure in the molecule, and vinyl polymers are a favorable example of the copolymer (A). Here, a hydroxyl group-containing functional group and a group having a carbosiloxane dendrimer structure are introduced into side chain position on a chain-form molecular main chain composed of polymerized unsaturated units. The copolymer (A) according to the present invention is preferably a vinyl copolymer having the carbosiloxane dendrimer structure and the hydroxyl group in side chain position on a main chain of polymerized vinyl units.

[0017] The copolymer (A) contains a group that has a carbosiloxane dendrimer structure. This carbosiloxane dendrimer structure denotes a high molecular weight group that is highly regularly branched in a radiating manner from a single core or nucleus. A highly branched si loxane · silalkylene copolymer is an example of a carbosiloxane dendrimer having such a structure; refer in th is regard to JP 1 1 -001 530 A. The carbosiloxane dendrimer structure in the vinyl polymer in the present invention is a group given by the following formula ( 1 ). [0018] formula (1):

[0019] Z in formula (1 ) is a divalent organic group, and the number of repeat units p thereof is 0 or 1. The divalent organic group Z is not particularly limited, but can be exemplified by alkylene groups, arylene groups, aralkylene groups, ester-containing divalent organic groups, ether-containing divalent organic groups, ketone-containing divalent organic groups, and amide group-containing divalent organic groups. Organic groups preferred among the preceding are given by the following formulas.

0020]

[0021 ] R in the preceding formulas is a C j . i o alkylene group, for example, methyl ethylene, propylene, and butylene. Methylene and propylene are preferred among the preceding. R is a C\.\Q alkyl group, for example, methyl, ethyl, propyl, and butyl.

Methyl is preferred among the preceding. R¹¹ is a CJ.JO alkylene group, for example, an alkylene group such as methylene, ethylene, propylene, and butylene. Ethylene is preferred among the preceding, d is an integer from 0 to 4, and e is 0 or 1.

1 2

[0022] R and R are independently a C\.\Q alkyl group, an aryl group, or an aralkyi group, for example, a C\.\o straight-chain or branched-chain alkyl group such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and so forth; a C3.10 cyclic alkyl group such as cyclopentyl, cyclohexyl, and so forth; a C6-10 ^aryl group such as phenyl, tolyl, xylyl, and so forth; a C7.10 aralkyi group such as benzyl; and groups provided by at least partially replacing the carbon-bonded hydrogen in the preceding groups with a halogen atom, e.g., fluorine, or with an organic group that contains, e.g., a carbinol group, epoxy group, glycidyl group, acyl group, carboxyl group, amino group, methacryl group, mercapto group, amide group, or oxyalkylene group. The alkyl group, aryl group, or aralkyi group is preferably an unsubstituted C\.\Q alkyl group, aryl group, or aralkyi group; is more preferably an unsubstituted Ci_6 alkyl group or aryl group; and

particularly preferably is methyl, ethyl, or phenyl.

[0023] L¹ is the silylalkyl group given by the following formula (2) when i = 1. [0024] formula (2):

[0025] Z and p in the formula are defined as above, and R and R are defined as above. i in the preceding formula is an integer from 1 to 10 that indicates the total number of generations of the silylalkyl group, and is preferably from 1 to 5 from the perspective of synthesis and more preferably is from 1 to 3. On the other hand, i is preferably at least 2 from the standpoint of properties such as the hardness, staining/soiling resistance, water repellency, and so forth of the cured layer provided by the cure of the curable

composition according to the present invention, and second generation and third generation carbosi loxane dendrimer structures, in which i is 2 and 3, are included in the particularly favorable embodiments of the present invention. [0026] is a group selected from the group consisting of the hydrogen atom, C \ . \ Q alkyl groups, aryl groups, aralkyl groups, and the aforementioned silylalkyl group, wherein when i = c— with c being an integer from 1 to 10 that indicates the generation of the silylalkyl group and is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1 or 2— is the hydrogen atom, a C J . J O alkyl group, an aryl group, or an aralkyl group, and when i < c, is the aforementioned silylalkyl group, a' is an integer from 0 to 3 and is preferably 0 to 2, more preferably 0 or 1 , and even more preferably 0.

[0027] The aforementioned carbosiloxane dendrimer structure is a chemical structure that is highly branched in a radiative configuration from a single silicon atom, and i, which indicates the total number of generations for this silylalkyl group, indicates the degree of branching. For example, when the total number of generations i is 1 and L' is, for example, the methyl group, the aforementioned carbosiloxane dendrimer structure denotes the fol lowing structure

[0028]

wherein Z, p, R , and R are defined as above and a is an integer from 0 to 3.

[0029] Similarly, when the generation i is 2 and is, for example, the methyl group, the aforementioned carbosi loxane dendrimer structure denotes the structure given below for p = 1 . The carbosiloxane dendrimer structure indicated by the following structure is cal led a "second generation type", and the copolymer (A) according to the present invention particularly preferably has a group that has this carbosiloxane dendrimer structure

[0030]

wherein Z, R , and R are defined as above and a and a are integers from 0 to 3.

[0031] When the generation i is 3 and is, for example, the methyl group, the aforementioned carbosiloxane dendrimer structure denotes the structure given below p - 1 . The carbosiloxane dendrimer structure indicated by the following structure is called a "third generation type", and the copolymer (A) according to the present invention particularly preferably has a group that has this carbosiloxane dendrimer structure [0032]

2 2 3

wherein Z, R , and R are defined as above and a , a , and a are integers from 0 to 3.

[0033] The following are preferred for the aforementioned carbosiloxane dendrimer structure. The carbosi loxane dendrimer structure given by formula (2-5) is particularly preferred from the standpoint of the properties of the coating layer, e.g., the hardness, staining/soiling resistance, water repellency, and so forth.

[0034]

wherein Z and R are defined as above

[0035]

wherein Z and R are defined as above [0036] A group having the carbosiloxane dendrimer structure described above has a structure in which the carbosiloxane unit broadens out into a dendrimer shape, and as a consequence is a hydrophobic functional group that, in comparison to a chain-form polysiloxane unit or a simple branched polysiloxane unit, can form a cured layer with a much higher hardness, can provide the cured layer with properties such as a higher water repellency (higher water resistance), and can prevent the surface of a coating film from becoming extremely smooth. In addition, a group having the previously described carbosi loxane dendrimer structure is chemically stable and as a consequence does not cause problems such as degradation of the curable composition with elapsed time and thus makes long-term storage possible.

[0037] A group having the carbosiloxane dendrimer structure described above can be introduced into the copolymer by the copolymerization with the other unsaturated monomer of (a2) a radically copolymerizable unsaturated monomer given by the following formula ( )

[0038]

wherein Y is a group containing radical ly polymerizable unsaturation and Z, p, R , R , L ¹ , and a' are defined as above.

[0039] The unsaturation-containing group has a radically polymerizable unsaturated bond but is not otherwise particularly limited, and can be exemplified by the vinyl group, ally] group, (meth)acryl group, and so forth. [0040] Y in formula ( ) preferably has a group selected from the group consisting of acrylic group-containing organic groups and methacrylic group-containing organic groups given by the following general formulas

[0041]

wherein

4

R is the hydrogen atom or a methyl group and

R⁵ is a C i _ i o alkylene group

[0042]

wherein

4 5

R and R are defined as above,

[0043]

alkenylaryl group-containing organic groups given by the following general formula

wherein

R⁶ is the hydrogen atom or a methyl group,

7

R is a C \ . \ o alkyl group,

R is a C \ . i o alkylene group, b is an integer from 0 to 4, and c is 0 or 1, and

C2-10 alkenyl groups.

[0044] This component (a2) can be exemplified by the following formulas.

[0045]

[0047] These carbosiloxane dendrimer structure-containing unsaturated monomers can be produced, for example, according to the method for producing branched siloxane · silalkylene copolymers described in JP 1 1 -001 530 A (Japanese Patent Appl ication 09- 1 71 154).

[0048] A characteristic feature of the copolymer (A) according to the product of the present invention is that it has, in addition to the carbosi loxane dendrimer structure, the hydroxyl group in its molecule. The hydroxyl group (-OH) is a component that is reactive with isocyanate-type curing agents, and, when a curable resin undergoes curing mainly by a condensation reaction, the copolymer (A) is then efficiently incorporated into the cured resin system . As a result, the copolymer (A) according to the product of the present invention exhibits an improved affinity for curable resins, and the compatibility during curing and the transparency (uniformity) of the cured layer are improved.

[0049] This hydroxyl group (-OH) may be directly bonded to the main chain of the copolymer (A) or may be bonded to the main chain of the copolymer (A) across a divalent organic group (Z) as -Z-OH. This Z can be exemplified by the same divalent organic groups as already described above.

[0050] This hydroxyl group is introduced into the copolymer by the copolymerization with the other unsaturated monomer of (a l ) an unsaturated monomer that contains at least one hydroxyl group in the molecule. This component (a l ) can be exemplified by vinyl monomers that have the hydroxyl group in the molecule, for example, acrylate esters that have the hydroxyl group in the molecule, methacrylate esters that have the hydroxyl group in the molecule, allyl compounds that have the hydroxyl group in the molecule, vinyl ether compounds that have the hydroxyl group in the molecule, unsaturated carboxamide compounds that have the hydroxyl group in the molecule, unsaturated fatty acids that have the hydroxyl group in the molecule, unsaturated fatty acid esters that have the hydroxyl group in the molecule, and monomers obtained by addition reacting various hydroxyl group-containing monomers with an ε-caprolactone adduct. A single one of the preced ing may be used or two or more may be used in combination.

[0051] Component (a l ) can be specifical ly exemplified by the following:

(meth)acrylate esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl

(meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4- hydroxybutyl (meth)acrylate, methyl 2-(hydroxymethyl)acrylate, ethyl 2- (hydroxymethyl)acrylate, butyl 2-(hydroxymethyl)acrylate, (4- hydroxymethylcyclohexyl)methyl (meth)acrylate, glycerol mono(meth)acrylate, 2- (meth)acryloyloxyethyl 2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl

(meth)acrylate, and so forth; ally 1 compounds such as ally 1 alcohol, 2-hydroxyethyl ally 1 ether, and so forth; vinyl ether compounds such as 2-hydroxyethyl vinyl ether, 4- hydroxybutyl vinyl ether, 6-hydroxyhexyl vinyl ether, and so forth; unsaturated carboxamide compounds such as N-methylol(meth)acrylamide, N-methylolcrotonamide, and so forth; hydroxyl group-containing unsaturated fatty acids such as ricinoleic acid and so forth; hydroxyl group-containing unsaturated fatty acid esters such as alkyl ricinoleate and so forth; and monomers obtained by addition reacting these hydroxyl group-containing monomers with an ε-caprolactone adduct.

[0052] Particularly favorable examples of component (al ) are acrylate esters and methacrylate esters, in each case having a hydroxyalkyl group in the molecule, and these can be more specifically exemplified by hydroxyl group-containing vinyl monomers such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, and 2-hydroxypropyl methacrylate.

[0053] The copolymer (A) according to the product of the present invention contains the hydroxyl group and the previously described carbosiloxane dendrimer structure in its molecule and is obtained by the copolymerization of the previously described components (a l ) and (a2), but may also optionally be a copolymer obtained using (a3) an unsaturated monomer that does not contain the hydroxyl group in the molecule. In particular, the component (a3) unsaturated monomer favorably forms a portion of the main chain of the copolymer (A) and is advantageously used as desired as a means for introducing different types of functional groups into the copolymer (A) according to the product of the present invention. In addition, the co-use of these monomers makes it possible to obtain the copolymer in an economically advantageous manner while imparting desired properties, such as blocking resistance or a leveling property, to the coating layer. It may also be possible to obtain additional improvements in properties such as the solubility through the selection of an unsaturated monomer.

[0054] The component (a3) unsaturated monomer can be favorably exemplified by vinyl monomers that do not have a hydroxyl group. Specific examples are as follows: lower alkyl acrylates and lower alkyl methacrylates such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, isopropyl acrylate, and isopropyl methacrylate; glycidyl acrylate and glycidyl methacrylate; lower acrylates and methacrylates that have a C j .6 lower alkyl group, such as n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert- butyl acrylate, tert-butyl methacrylate, n-hexyl acrylate, n-hexyl methacrylate,

cyclohexyl acrylate, and cyclohexyl methacrylate; higher acrylates and methacrylates such as 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, octyl acrylate, octyl

methacrylate, lauryl acrylate, lauryl methacrylate, stearyl acrylate, and stearyl

methacrylate; the vinyl esters of lower fatty acids, such as vinyl acetate and vinyl propionate; esters of higher fatty acids, such as vinyl butyrate, vinyl caproate, vinyl 2- ethylhexanoate, vinyl laurate, and vinyl stearate; aromatic vinyl monomers such as styrene, vinyltoluene, benzyl acrylate, benzyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, and vinylpyrrolidone; amino group-containing vinyl monomers such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, and diethylaminoethyl methacrylate; am ide group-containing vinyl monomers such as acrylamide, methacrylamide, N-methylolacrylamide, N- methylolmethacrylamide, N-methylolacrylamide, N-methoxymethylmethacrylamide, isobutoxymethoxyacrylamide, isobutoxymethoxymethacrylamide, N,N- dimethylacrylamide, and Ν,Ν-dimethylmethacrylamide; carboxylic acid-containing vinyl monomers such as acryl ic acid, methacryl ic acid, itaconic acid, crotonic acid, fumaric acid, and maleic acid; ether bond-containing vinyl monomers such as tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate, butoxyethyl acrylate, butoxyethyl methacrylate, cetyl vinyl ether, and 2-ethylhexyl vinyl ether; unsaturated group-containing silicone compounds such as a polydimethylsiloxane containing the acrylic group or methacryl ic group at one terminal and a polydimethylsiloxane containing an alkenylaryl group at one terminal ; butadiene; vinyl chloride; vinylidene chloride; acrylonitrile; methacrylonitrile; dibutyl fumarate; maleic anhydride; dodecylsuccinic anhydride; acryl glycidyl ether; methacryl glycidyl ether; 3,4-epoxycyclohexylmethyl acrylate; 3,4- epoxycyclohexylmethyl methacrylate; the alkal i metal salts, ammonium salts, and organic amine salts of radically polymerizable unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, and maleic acid; radically polymerizable unsaturated monomers that have the sulfonic acid group, such as styrenesulfonic acid, as well as their alkali metal salts, ammonium salts, and organic amine salts; quaternary ammonium salts derived from acrylic acid or methacrylic acid, such as 3-methacryloxypropyltrimethylammonium chloride; and the methacrylic acid esters of alcohols that have a tertiary amine group, such as a diethylamine ester of methacrylic acid, as well as their quaternary ammonium salts. Lower acrylates and methacrylates that have a C .^ lower alkyl group are preferred. [0055] Component (a3) may also be an unsaturated monomer that has a silicon-bonded alkoxy group, and specific examples in this regard are

methacryloxypropyltriethoxysilane, acryloxypropyltriethoxysilane,

methacryloxypropyltrimethoxysilane, acryloxypropyltrimethoxysilane,

vinyltriethoxysi lane, vinyltrimethoxysilane, and vinyltris(2-methoxyethoxy)silane.

[0056] Multifunctional vinyl monomers may also be used as component (a3), for example, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1 ,4-butanediol diacrylate, 1 ,4- butanediol dimethacrylate, 1 ,6-hexanediol diacrylate, 1 ,6-hexanediol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trioxyethylacrylate, trimethylolpropane trioxyethylmethacrylate, and unsaturated group- containing silicone compounds such as a polydimethylsiloxane endblocked by an alkenylaryl group at both molecular chain terminals.

[0057] A vinyl monomer containing a fluorinated organic group may also be used as component (a3). This vinyl monomer containing a fluorinated organic group is preferably given by the general formula CH2=CR ^{1 5}COOR , wherein R^{1 5} is the hydrogen f

atom or a methyl group and R is a fluorinated organic group and can be exemplified by the fluoroalkyl groups described above and fluoroalkyloxyfluoroalkylene groups. The compounds given by the following formulas, in which z is an integer from 1 to 4, are specific examples of this component (a3): CH₂=CCH₃COO-CF3 , CH₂=CCH₃COO-C₂F5, CH2=CCH₃COO-nC₃F7, CH₂=CCH₃COO-CF(CF₃)₂, CH₂=CCH₃COO-nC₄F₉, CH2=CCH₃COO-CF₂CF(CF₃)₂, CH₂=CCH₃COO-nC5F ! j , CH₂=CCH₃COO-nC₆F _{1 3} , CH₂=CCH₃COO-nC₈F i 7, CH₂=CCH₃COO-CH₂CF₃, CH₂=CCH₃COO-CH(CF₃)₂, CH₂=CCH₃COO-CH₂CH(CF₃)2, CH₂=CCH₃COO-CH₂(CF₂)2F, CH₂=CCH₃COO- CH₂(CF₂)3 F, CH2=CCH₃COO-CH₂(CF2)4F, CH2=CCH₃COO-CH₂(CF2)6F,

CH2=CCH₃COO-CH2(CF₂)8F, CH₂=CCH3COO-CH₂CH2CF3, CH₂=CCH₃COO- CH₂CH₂(CF₂)2F, CH2=CCH3COO-CH₂CH2(CF₂)3 F, CH₂=CCH₃COO- CH₂CH2(CF2)₄F, CH2=CCH3COO-CH₂CH₂(CF2)6F, CH₂=CCH₃COO- CH₂CH₂(CF2)₈F, CH2=CCH₃COO-CH2CH₂(CF₂) i oF, CH₂=CCH₃COO- CH₂CH₂(CF₂) i 2F, CH₂=CCH3COO-CH₂CH2(CF2) i 4F, CH₂=CCH₃COO- CH₂CH₂(CF₂) i 6F, CH₂=CCH₃COO-CH2CH2CH2CF3, CH₂=CCH₃COO- CH₂CH₂CH2(CF2)2F, CH₂=CCH3COO-CH₂CH2CH2(CF2)2H, CH₂=CCH₃COO- CH₂(CF₂)₄H, CH2=CCH3COO-CH₂CH₂(CF2)3H, CH2=CCH3COO-CH₂CH₂CF(CF3)- [OCF₂CF(CF3)]_z-OC₃F7, CH₂=CCH3COO-CH2CH2CF2CF2-[OCF2CF(CF₃)]_z-

OC₃F₇CH₂=CHCOO-CF3, CH₂=CHCOO-C₂F₅, CH₂=CHCOO-nC₃F₇, CH₂=CHCOO- CF(CF₃)₂, CH₂=CHCOO-nC₄F9, CH2=CHCOO-CF₂CF(CF₃)2, CH₂=CHCOO-nC₅ F ₁ j , CH₂=CHCOO-nC₆F _{1 3}, CH₂=CHCOO-nC₈F i ₇, CH₂=CHCOO-CH₂CF₃, CH₂=CHCOO- CH(CF₃)₂, CH2=CHCOO-CH₂CH(CF₃)2, CH₂=CHCOO-CH₂(CF₂)2F, CH₂=CHCOO- CH₂(CF₂)3F, CH₂=CHCOO-CH₂(CF₂)4F, CH₂=CHCOO-CH₂(CF₂)6F, CH₂=CHCOO- CH₂(CF₂)₈F, CH2=CHCOO-CH₂CH₂CF3, CH₂=CHCOO-CH₂CH2(CF2)2F,

CH2=CHCOO-CH₂CH₂(CF2)3 F, CH2=CHCOO-CH₂CH₂(CF2)4F, CH₂=CHCOO- CH₂CH2(CF₂)6F, CH₂=CHCOO-CH₂CH2(CF2)8F, CH₂=CHCOO-CH₂CH2(CF₂) i oF, CH2=CHCOO-CH₂CH₂(CF2) i 2F, CH₂=CHCOO-CH₂CH2(CF2) i 4F, CH₂=CHCOO- CH₂CH₂(CF₂) i 6F, CH₂=CHCOO-CH2CH₂CH₂CF3, CH₂=CHCOO- CH₂CH₂CH2(CF2)2F, CH2=CHCOO-CH2CH₂CH2(CF₂)2H, CH₂=CHCOO- CH₂(CF₂)₄H, CH2=CHCOO-CH₂CH₂(CF2)3H, CH2=CHCOO-CH₂CH₂CF(CF3)- [OCF₂CF(CF3)]_z-OC₃F7, and CH₂=CHCOO-CH2CH2CF₂CF2-[OCF2CF(CF3)]_z- OC3 F7.

[0058] Vinyl monomers given by the fol lowing formulas are preferred among the preceding: CH2=CHCOO-CH₂CH₂(CF2)6F, CH₂=CHCOO-CH₂CH2(CF2)8F, CH₂=CCH₃ COO-CH2CH2(CF2)6F, CH2=CCH3COO-CH₂CH₂(CF2)8F, CH₂=CHCOO- CH₂CF₃ and CH₂=CCH3COO-CH2CF₃. Vinyl monomers given by the following formulas are particularly preferred : CH₂=CHCOO-CH₂CF₃ and CH₂=CCH₃COO- CH₂CF₃.

[0059] Copolymer (A) is a copolymer provided by the copolymerization of the previously described unsaturated monomers (al ), (a2), and optional (a3). Any ratio can be used in this copolymerization; however, letting 100 mass parts be the mass of all the unsaturated monomers, i .e. , the sum of the masses of the unsaturated monomers (a l ) to (a3), the mass ratios for the individual components can be established as suitable in the range of (a l ) : (a2) : (a3) = 0. 1 to 99.9 : 0. 1 to 99.9 : 0 to 99.8, preferably in the range of (a l ) : (a2) : (a3) = 0.5 to 50.0 : 0.5 to 80.0 : 0 to 99.0, more preferably in the range of (a l ) : (a2) : (a3) = 3.0 to 30.0 : 2.0 to 70.0 : 0 to 95.0, and particularly preferably in the range of (a l ) : (a2) : (a3) = 5.0 to 20.0 : 7.0 to 60.0 : 20 to 88.0. In addition, a copolymer (A) that satisfies the condition {mass of component (a2) } > {mass of component (a l ) } is particularly preferred.

[0060] The copolymer (A) obtained using the previously described polymerization ratios, due to the introduction of the hydroxyl group and a group having the carbosiloxane dendrimer structure at prescribed ratios on the main chain, is useful when used as a base component for the excellent hardness, uniformity, transparency, solvent resistance, staining/soiling resistance, and water repel lency of the cured layer; is useful when synthesized in solvent because it provides a transparent state that is free of cloudiness; and is useful in that the curable composition has a particularly good timewise stability and a particularly good blending stability in all types of coating agents.

[0061] Radical polymerization methods and ionic polymerization methods can be used for the copolymerization method, but radical polymerization methods are preferred therebetween and the use of solution polymerization methods is particularly favorable. This solution polymerization is carried out by reacting the previously described unsaturated monomers in a solvent for 3 to 20 hours at a temperature of 50 to 1 50°C in the presence of a radical initiator. The solvent used here can be exemplified by aliphatic hydrocarbons such as hexane, octane, decane, cyclohexane, and so forth; aromatic hydrocarbons such as benzene, toluene, xylene, and so forth; ethers such as diethyl ether, dibutyl ether, tetrahydrofuran, dioxane, and so forth; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and so forth; esters such as methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, and so forth; alcohols such as methanol, ethanol, isopropyl alcohol, butanol, and so forth; and organosiloxane oligomers such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, hexamethyldisiloxane, octamethyltrisiloxane, and so forth. The heretofore known compounds typically used in radical polymerization methods can be used as the radical initiator, and specific examples are azobis compounds such as 2,2'- azobis(isobutyronitrile), 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4- dimefhylvaleronitrile), dimethyl 2,2'-azobis(2-methylpropionate), and so forth, and organic peroxides such as benzoyl peroxide, lauroyl peroxide, tert-butylperoxy benzoate, tert-butylperoxy 2-ethylhexanoate, and so forth. A single radical initiator may be used by itself, or two or more may be used in combination. The amount of radical initiator used is preferably in the range from 0. 1 to 5 mass parts per 100 mass parts for the total of components (a l ) to (a3). A chain transfer agent may also be added to the polymerization. This chain transfer agent can be specifically exemplified by mercapto compounds such as 2-mercaptoethanol, butyl mercaptan, n-dodecyl mercaptan, 3- mercaptopropyltrimethoxysilane, a polydimethylsi loxane that has the mercaptopropyl group, and so forth, and by halides such as methylene chloride, chloroform, carbon tetrachloride, butyl bromide, 3-chloropropyltrimethoxysilane, and so forth.

[0062] After the polymerization, purification can be carried out by a method in which the unreacted residual vinyl monomer is removed by treatment under reduced pressure with heating, or by a method in which a deodorization treatment is carried out by running a hydrogenation reaction in the presence of a hydrogenation catalyst in the presence or absence of a solvent and the light components are distilled off under reduced pressure while in contact with nitrogen gas. A purified product is particularly preferably used in the case of use in topical applications where low odor and compatibi lity with other cosmetic components are required. The solvents, reaction conditions, low pressure conditions, and so forth that are used in the purification of known organopolysiloxane copolymers can be used and selected without particular l imitation in and for the hydrogenation reaction and stripping step under consideration.

[0063] The copolymer (A) used by the present invention is the base component of the curable composition, and, viewed from the perspective of the ease of blending as a starting material and the workability of the obtained curable composition during coating operations, the number-average molecular weight of copolymer (A) is preferably from 3,000 to 2,000,000 and more preferably is from 5,000 to 800,000. Its state can be exempl ified by liquid, gum, paste, bulk solid, and powder, and it is preferably a dispersion or solution provided by dilution with a solvent. [0064] A characteristic feature of the curable composition according to the present invention is that the previously described copolymer (A) is cured by (B) at least one curing agent selected from the group consisting of isocyanate compounds and melamine compounds, which are curing agents that react with the hydroxyl group. The hydroxyl group (-OH) in the copolymer (A) is reactive with isocyanate-type and melamine-type curing agents, and, when a curable resin undergoes curing mainly by a condensation reaction, the copolymer (A) is then efficiently incorporated into the cured resin system . This results in an improved compatibi lity during curing for the composition as a whole and an improved hardness, transparency (uniformity), and staining/soiling resistance for the cured layer.

[0065] This curing agent (B) may be (B l ) an isocyanate compound, (B2) a melamine compound, or a mixture of the preceding, and in each case two or more of the compounds may be used in combination. Thus, the curable composition according to the present application can use, without particular limitation, an isocyanate system, a melamine system, or a cure system that combines these systems. However, viewed from the perspective of the reactivity with the copolymer (A), the curing agent preferably contains at least one or more isocyanate compounds (B l ) and particularly preferably contains at least one polyisocyanate compound (B l -2). Even when such an isocyanate- system curing agent is selected, a melamine-system curing agent may of course as desired be used in combination therewith. A curing catalyst may also be added on an optional basis.

[0066] The amount of the curing agent (B) in the curable composition of the present invention is not particularly limited, but the curing agent (B) is generally used in the range from 1 to 50 mass parts per 100 mass parts of the resin component in the curable composition comprising components (A) and (B). [0067] However, viewed from the perspective of the various properties of the cured layer, a range more favorable than the aforementioned general range exists with regard to the type and amount of the curing agent (B) in the curable composition of the present invention. Thus, the curing agent (B) preferably contains at least one isocyanate compound (B l ) and the molar equivalent for the isocyanate (-NCO) group in the curing agent is preferably in the range from 0.1 to 2.0 per 1 equivalent of the hydroxyl group (- OH) in the copolymer (A). In addition, a range that provides from 0.5 to 1 .5 equivalents of isocyanate groups per 1 equivalent of hydroxyl groups in the copolymer (A), i.e., a - OH/-NCO equivalent ratio in the range from 1 .0/0.5 to 1 .0/ 1 .5 , is preferred. The range of 1 /0.7 to 1 .2 for the equivalent ratio is more preferred. When the isocyanate group is used at less than 0. 1 mole per 1 mole hydroxyl group in the copolymer (A), the cured layer may not exhibit a satisfactory staining/soiling resistance, water repellency, and non- stickiness. The post-cure coating layer may have a poor workability when the isocyanate group is used at more than 2 moles per 1 mole hydroxyl group. The respective amounts of use can be calculated by the usual methods from the hydroxyl value of the copolymer (A) and the isocyanate group content of the isocyanate compound.

[0068] The isocyanate compound (B l ) curing agent can be specifically exemplified by polyisocyanate compounds, e.g., aliphatic types such as xylene diisocyanate, isophorone di isocyanate, and hexamethylene diisocyanate and their polyhydric alcohol adducts, biuret types, and trimer types, and aromatic types such as tolylene diisocyanate and diphenylmethane diisocyanate, and can be further exemplified by blocked isocyanate compounds. Viewed from the perspective of curability, polyisocyanate compounds (B l - 2) are preferred and polyisocyanate compounds such as hexamethylene diisocyanate are particularly preferred. A single species of isocyanate compound may be used by itself, or two or more species may also be used in combination. [0069] Commercial ly avai lable isocyanate compound (B l ) products can be exemplified by "Burnock" (trademark) from Dainippon Ink and Chemicals, Incorporated, "Sumidur" (trademark) from Sumitomo Bayer Urethane, Ltd., "Takenate" (trademark) from Takeda Chemical Industries, Ltd., "Coronate" (trademark) from Nippon Polyurethane Industry Co., Ltd., and "Duranate" (trademark) from Asahi Kasei Chemicals.

[0070] The melamine compound (B2) curing agent can be specifically exempl ified by dimethylolmelamine, trimethylolmelamine, tetramethylolmelamine,

pentamethylolmelamine, hexamethylolmelam ine, isobutyl ether-type melamine, n-butyl ether-type melam ine, and so forth. A single species of these melamine compounds can be used by itself or two or more species can be used in combination.

[0071] A curing catalyst may be incorporated on an optional basis, and the curing catalyst can be exempl ified by organometal compounds, amine compounds, and acidic compounds. The organometal compounds can be specifically exemplified by organotin compounds such as tin octylate, di-n-butyltin dioctate, di-n-butyltin dilaurate, di-n- octyltin bis(isooctyl thioglycolate), di-n-butyltin sulfide, and di-n-octyltin oxide;

organotitanium compounds such as tetraisopropoxytitanium, tetra-n-butoxytitanium, isopropyl triisostearoyltitanate, and isopropyl tris(dioctyl pyrophospate)titanate;

organoaluminum compounds such as aluminum isopropylate and aluminum

tris(acetylacetonate); as well as by zinc octylate and magnesium naphthenate. The amine compounds can be exemplified by triethylamine, ethylenediamine, diethylenetriamine, dimethylaminoethanol, and isophoronediamine. The acidic compounds can be

exemplified by para-toluenesulfonic acid, dodecylbenzenesulfonic acid, phthalic acid, phthalic anhydride, phosphoric acid, monoalkyl phosphates, dialkyl phosphates, and organic amine blocked compounds of the preceding. A single one or two or more of these curing catalysts may be used on an optional basis. The amount for the curing catalyst is preferably from 0.001 to 5 mass parts per 100 mass parts of the resin component of the coating agent.

[0072] Additives can be exemplified by dehydrating agents, pigments, dispersing agents, defoamants, thickeners, settl ing inhibitors, sagging inhibitors, leveling agents, matting agents, anti-scratching agents, ultraviolet absorbers, photostabilizers, oxidation inhibitors, antimicrobials, and so forth; one or more of these can be used.

[0073] The dehydrating agent can be exemplified by dimethoxymethane, 1 , 1 - dimethoxyethane, 1 , 1 -dimethoxypropane, 1 , 1 -dimethoxybutane, and 1 , 1 - dimethoxycyclohexane and by hydrolyzable esters such as ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, dimethyldimethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ- methacryloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ- aminopropyltriethoxysilane, methyl silicate, ethyl silicate, and so forth. The moisture fraction in the system can be removed by the addition of this dehydrating agent, which can bring about even further improvement in the storage stabil ity. The amount of use of the dehydrating agent is preferably from 0. 1 to 50 mass parts per 100 mass parts of the resin component in the coating agent.

[0074] The quantity of use of the other additives is not particularly limited, and these additives can be added and used in the quantities of use known for the usual additives for curable resin coating agents in conformity with the particular application.

[0075] The curable composition of the present invention can be cured as such, but it is preferably coated on a substrate to thereby form on the substrate a high-hardness cured layer that exhibits an excellent uniformity, transparency, solvent resistance,

staining/soiling resistance, and water repellency.

[0076] The usual coating methods known for curable resin coating agents can be selected without particular limitation, in accordance with the shape of the substrate and the purpose of the coating, for the method of applying the coating agent of the present invention to a substrate. In specific terms, any of the following may be used: bar coating methods, rol l coating methods, blade coating methods, gravure coating methods, bead coating methods, curtain flow coating methods, immersion coating methods, and spray coating methods. Coating can be carried out on only one side or on both sides of a substrate and can be carried out on a portion of a substrate or over the entire substrate.

[0077] After application, curing can be performed at any temperature from ambient temperature to 300°C; however, drying is preferably performed for 5 seconds to 60 minutes by heating at a temperature of 60 to 250°C in order to promote solvent

evaporation and accelerate the crosslinking reaction. Higher curing temperatures provide shorter curing times, and the curing time can be further shortened by the co-use of a curing catalyst. After the coating has been dried in order to accelerate the crosslinking reaction, the coating can also be aged or matured for 1 to 7 days at a temperature of 30 to 120°C.

[0078] The thickness of the coating film provided by application of the coating agent of the present invention can be selected without particular limitation in accordance with the shape of the substrate and the purpose of the coating, but is typically in the range from 0. 1 to 100 μιτι and preferably is 0.5 to 50 μπι.

[0079] Materials that may be coated with the coating agent of the present invention can be exemplified by metals, inorganic materials, plastics, and composite materials. The metals can be exemplified by stainless steel, aluminum, tin plate, galvanized plate, mild steel sheet and plate, copper, brass, various types of plated steel sheet and plate, titanium, and so forth. The coating agent of the present invention can also be advantageously used on metal substrates that have been subjected to a surface treatment such as a conversion treatment or an alumite treatment. The inorganic material can be exempl ified by glass, mortar, slate, concrete, roof tile, and so forth. The plastics can be exemplified by moldings of, e.g., surface-treated polypropylene, polyethylene, acrylic, polycarbonate, polystyrene, polyethylene terephthalate, nylon, polyester, rubber, elastomers, and so forth and by products provided by processing the preceding into a film. The composite materials can be exemplified by fiber-reinforced thermosetting plastics (FRP), fiber- reinforced thermoplastic plastics (FRTP), laminates, sandwich materials provided by the press bonding of a metal with an organic material, and plastics bearing a vapor-deposited metal film.

[0080] The cured layer provided by the cure of the curable composition of the present invention exhibits a high hardness and an excellent uniformity, transparency, solvent resistance, staining/soi l ing resistance, and water repellency and is therefore effective, for example, for blocking greasy contaminants, dust and dirt borne in the air, and the contaminants admixed in exhaust gas and rainwater; for blocking various types of illicit materials such as graffiti, posters, bills, and stickers; and for preventing snow accretion, icing, and the attachment of aquatic microorganisms.

[0081] The article bearing the cured layer according to the present invention is not particularly limited and can be exemplified by articles used in the kitchen and home, for example, the area around kitchen stoves, the doors of storage cabinets, exhaust fans, lighting covers, and so forth, in each case bearing a cured layer for the purpose of blocking greasing contaminants; building materials, such as concrete, tile and so forth, in each case bearing a cured layer for the purpose of preventing the soiling of exterior walls; construction features such as roadway tunnels, freeway sound-deadening walls, and so forth, in each case bearing a cured layer for the purpose of preventing staining due to exhaust gases; outside features such as exterior walls, public phone booths, utility poles, public toilets, and so forth, in each case bearing a cured layer for the purpose of preventing the attachment of graffiti, posters, bills, stickers and so forth; building elements and infrastructure elements such as roofs, power l ines, and so forth, in each case bearing a cured layer for the purpose of preventing snow accretion and icing; and ships, vessels, immersed structures, and so forth, in each case bearing a cured layer for the purpose of preventing the attachment of barnacles and so forth .

[0082] Plate-form and sheet-form substrates of, e.g., a metal, inorganic material, plastic, or composite, that bear a cured layer of the present invention are very useful as high- performance materials due to the formation on their surface of a high-hardness functional coating that exhibits water repellency and staining/soiling resistance.

Examples

[0083] The present invention is specifically described by the practical examples and comparative examples given below, but the present invention is not limited to the following examples. The viscosity is the value measured at 25°C.

[0084]

Method for measuring the viscosity of the copolymer

The kinematic viscosity of the copolymer was measured by a capillary viscosity measurement procedure using a Ubbelohde viscometer.

Method for measuring the molecular weight and dispersitv of the copolymer

The molecular weight and dispersity of the copolymer were measured by gel permeation chromatography (GPC). The molecular weight obtained for the copolymer is reported as the number-average molecular weight as polystyrene.

Method for measuring the solids fraction concentration of the copolymer 1 g of the silicone-modified vinyl copolymer obtained in the particular example was weighed into an aluminum dish and then heated for 2 hours in a 1 50°C oven.

The solids fraction concentration was calculated from the amount of solvent evaporation (g).

[0085] [Synthesis Example 1 ]

355 g butyl acetate was introduced into a 1 000-mL four-neck flask equipped with a stirrer, reflux condenser, thermometer, and nitrogen introduction tube and was stirred and heated to 70°C under a nitrogen atmosphere.

The following were added dropwise to this butyl acetate over 2 hours:

(a-3- 1 ) 102.5 g of methyl methacrylate,

(a-3-2) 22.5 g of n-butyl acrylate,

(a- 1 - 1 ) 25 g of 2-hydroxyethyl methacrylate,

(a-2- 1 ) 100 g of the carbosiloxane dendrimer structure-containing vinyl monomer with the following formula,

and 2.5 g of the radical polymerization initiator V-601 from Wako Pure Chemical Industries, Ltd.

After the completion of the dropwise addition, a reaction was run for 6 hours at

70°C to obtain a silicone-modified vinyl copolymer (A l ) with a number-average molecular weight as polystyrene of 8,200, a dispersity of 9.24, a kinematic viscosity of

2

108.26 mm /s, and a solids fraction concentration of 36.9%. [0086] [Synthesis Example 2] A silicone-modified vinyl copolymer (A2) with a number-average molecular weight as polystyrene of 25,300, a dispersity of 6.92, a kinematic viscosity of 422.69

2

mm /s, and a sol ids fraction concentration of 40.4% was obtained proceeding as in Synthesis Example 1 , but using

(a-2-2) a carbosiloxane dendrimer structure-containing vinyl monomer with the following formula

in place of the component (a-2- 1 ) used in Synthesis Example 1 .

[0087] [Comparative Synthesis Example 1 ]

A si licone-modified vinyl copolymer (C I ) with a number-average molecular weight as polystyrene of 12,900, a dispersity of 9.04, a kinematic viscosity of 404.93

2

mm /s, and a sol ids fraction concentration of 39. 1 % was obtained proceeding as in

Synthesis Example 1 , but using a straight chain polysiloxane structure-containing vinyl monomer with the following formula

in place of the component (a-2- 1 ) used in Synthesis Example I .

[0088] [Comparative Synthesis Example 2]

A cloudy white silicone-modified vinyl copolymer (C2) with a number-average molecular weight as polystyrene of 2,700, a dispersity of 9.94, a kinematic viscosity of 21 .67 mm /s, and a solids fraction concentration of 3 1 .7% was obtained proceeding as in

in place of the component (a-2- 1 ) used in Synthesis Example 1 .

[0089] [Comparative Synthesis Example 3]

A cloudy white sil icone-modified vinyl polymer (C3) with a number-average molecular weight as polystyrene of 6,900, a dispersity of 7.63, a kinematic viscosity of

2

2052.79 mm /s, and a solids fraction concentration of 37.8% was obtained proceeding as in Synthesis Example 1 , but using a straight chain polysiloxane structure-containing vinyl monomer with the following formula

in place of the component (a-2- 1 ) used in Synthesis Example 1 .

[0090] Coating agents containing the silicone-modified vinyl polymers obtained in the synthesis examples and comparative synthesis examples were evaluated as described below. The Sum idur (trademark) N3300 used as the curing agent is a polyfunctional isocyanate compound in which the main component is a hexamethylene diisocyanate trimer, i.e., a polyisocyanate compound.

[0091] [Practical Example 1 ] The curable composition of Practical Example 1 , in which NCO/OH = 1 .5, was obtained by mixing the following to uniformity: 1 5 g of the silicone-modified vinyl copolymer (A l ) of Synthesis Example 1 , which had a solids fraction concentration of 36.9% and an OH value of 43.2; 1 .07 g of a polyfunctional isocyanate compound (B l ), i.e., Sumidur (trademark) N3300 from Sumitomo Bayer Urethane, Ltd., which had an NCO content of 25%; 1 .32 g of a 0.1 wt% butyl acetate solution of dibutyltin dilaurate; and 4.64 g of butyl acetate as a diluent solvent. This curable composition was coated using a Mayer bar on an aluminum plate (JIS H 4000, 5 x 50 x 150 mm) and was cured by heating for 1 5 minutes at 1 50°C to yield a coated aluminum plate having a dry film thickness of 10 μπι.

[0092] [Practical Example 2]

The curable composition of Practical Example 2, in which NCO/OH = 1 .5, was obtained by mixing the following to uniformity: 1 5 g of the silicone-modified vinyl copolymer (A2) of Synthesis Example 2, which had a solids fraction concentration of 40.4% and an OH value of 43.2; 1 . 1 8 g of a polyfunctional isocyanate compound (B l ), i .e., Sumidur (trademark) N3300 from Sumitomo Bayer Urethane, Ltd., which had an NCO content of 25%; 1 .45 g of a 0.1 wt% butyl acetate solution of dibutyltin dilaurate; and 6.50 g of butyl acetate as a diluent solvent. This curable composition was coated using a Mayer bar on an aluminum plate (JIS H 4000, 5 x 50 x 150 mm) and was cured by heating for 1 5 minutes at 1 50°C to yield a coated aluminum plate having a dry film thickness of 1 0 μπι.

[0093] [Comparative Example 1 ]

A curable composition containing a sil icone-modified vinyl resin, in which NCO/OH = 1 .5, was obtained by thoroughly mixing the following: 1 5 g of the silicone- modified vinyl copolymer (C I ) of Comparative Synthesis Example 1 , which had a solids fraction concentration of 39. 1 % and an OH value of 43.2; 1 . 14 g of a polyfunctional isocyanate compound (B l ), i .e., Sumidur (trademark) N3300 from Sumitomo Bayer Urethane, Ltd., which had an NCO content of 25%; 1 .40 g of a 0. 1 wt% butyl acetate solution of dibutyltin dilaurate; and 5.8 1 g of butyl acetate as a diluent solvent. This curable composition was coated using a Mayer bar on an aluminum plate (JIS H 4000, 5 x 50 x 1 50 mm) and was cured by heating for 1 5 minutes at 1 50°C to yield a coated aluminum plate having a dry film thickness of 1 0 μηι.

[0094] [Comparative Example 2]

A curable composition containing a sil icone-modified vinyl resin, t in which NCO/OH = 1 .5, was obtained by thoroughly mixing the following: 15 g of the si l icone- modified vinyl copolymer (C2) of Comparative Synthesis Example 2, which had a solids fraction concentration of 3 1 .7% and an OH value of 43.2; 0.92 g of a polyfunctional isocyanate compound (B l ), i.e., Sumidur (trademark) N3300 from Sumitomo Bayer Urethane, Ltd., which had an NCO content of 25%; 1 . 14 g of a 0. 1 wt% butyl acetate solution of dibutyltin dilaurate; and 1 .87 g of butyl acetate as a diluent solvent. This curable composition was coated using a Mayer bar on an aluminum plate (JIS H 4000, 5 x 50 x 150 mm) and was cured by heating for 1 5 minutes at 1 50°C to yield a coated aluminum plate having a dry film thickness of 1 0 μπι.

[0095] [Comparative Example 3]

A curable composition containing a si l icone-modified vinyl resin, in which NCO/OH = 1 .5 , was obtained by thoroughly mixing the following: 1 5 g of the silicone- modified vinyl copolymer (C3) of Comparative Synthesis Example 3, which had a solids fraction concentration of 37.8% and an OH value of 43.2; 1 .10 g of a polyfunctional isocyanate compound (B l ), i.e., Sumidur (trademark) N3300 from Sumitomo Bayer Urethane, Ltd., which had an NCO content of 25%; 1 .35 g of a 0. 1 wt% butyl acetate solution of dibutyltin dilaurate; and 5. 12 g of butyl acetate as a di luent solvent. This curable composition was coated using a Mayer bar on an aluminum plate (JIS H 4000, 5 x 50 x 150 mm) and was cured by heating for 15 minutes at 150°C to yield a coated aluminum plate having a dry film thickness of 1 0 μηι .

[0096] The following properties were evaluated on the coated aluminum plates obtained as described above, and the results are given in Table 1 .

Appearance

The appearance of the resulting coating fi lm was visual ly inspected and was evaluated using the fol lowing criteria.

O The coating film is transparent,

x : The coating film presents white cloudiness.

Staining/soiling resistance

The cured coating film was marked with a Magic Ink blue ink pen from Pentel Co., Ltd., and was air-dried for 1 0 minutes and was then wiped with a KimWipe. The status of crawl ing by the Magic Ink when marking was performed and the status of the wiping- off effort were visually inspected and evaluated using the following criteria.

O : The Magic Ink underwent crawling and could be easily wiped off.

x The Magic Ink did not undergo crawling and it was difficult to wipe off the text.

The contact angle with water

A water droplet was placed on the cured coating film and the contact angle with the water was measured using a DM-700 contact angle meter from Kyowa Interface Science Co., Ltd.

Pencil hardness The measurement was performed using a method in accordance with the pencil scratch test of JIS K 5400-6- 14.

Coefficient of friction

The measurement was carried out under the following conditions using a Heidon

Type 14 friction tester from Shinto Scientific Co., Ltd. : 100 x 15 mm SUS cylinder, 50 g load, and 100 mm/minute pull rate.

[0097] [Table 1 .]

[0098] As shown in Table 1 , the curable composition of the present invention not only exhibits a high compatibility, a high staining/soil ing resistance, and a high water repellency, but also has a higher hardness than a curable composition that contains a straight chain polysiloxane. In particular, these effects were seen to a particularly significant degree in Practical Example 1 , which used the silicone-modified vinyl copolymer (A l ) of Synthesis Example 1 ; this silicone-modified vinyl copolymer (A l ) had a second generation carbosiloxane dendrimer structure.

[0099] [Industrial Applicability]

The curable composition of the present invention has as its base component a copolymer that contains the hydroxyl group and a carbosiloxane dendrimer structure, and can provide a transparent resin solution. In addition, a cured layer provided by reacting an isocyanate compound with the copolymer of the present invention as a base component exhibits, due to the effect of the carbosiloxane dendrimer structure, a high transparency, a high hardness, and a high staining/soiling resistance. Due to this, the curable composition of the present invention, through its appl ication on any of a variety of articles, can function as a surface protectant and can impart staining/soiling resistance and thus can be used to counter a broad range of stains, dirt, and contaminants, such as oily or greasy contaminants and stains, the dust and dirt borne in the air, and the contaminants admixed in exhaust gas and rainwater. An article having a cured layer provided by the cure of the curable composition according to the present invention has a high-hardness functional coating film and thus is very useful as a high performance material.

Claims

CLAIMS 1. A curable composition comprising

(A) a copolymer that contains in the molecule a hydroxyl group and a group having a carbosiloxane dendrimer structure given by the following formula ( 1 ) and

wherein

Z is a divalent organic group, p is 0 or 1 ,

1 2

R and R are each independently a C \ . \ Q alkyl group, an aryl group, or an aralkyl group, and

L ¹ is a silylalkyl group represented by the following structural formula (2) when i

1

=

wherein Z and p are defined as above,

1 2

R and R are defined as above, i is an integer from 1 to 10 that indicates the total number of generations of the si lylalkyl group, is a group selected from the group consisting of the hydrogen atom, C ] _ i o alkyl groups, aryl groups, aralkyl groups, and the aforementioned silylalkyl group, wherein when ί = c with c being an integer from 1 to 10 that indicates the generation of the silylalkyl group, is the hydrogen atom, a C \ . \ Q alkyl group, an aryl group, or an aralkyl group, and when i < c, L*⁺' is the aforementioned silylalkyl group, and a' is an integer from 0 to 3.

The curable composition according to claim 1 , wherein the copolymer (A) is a copolymer provided by the copolymerization of at least one or more selections from each of the following unsaturated monomers (a l ) and (a2): (a l ) unsaturated monomers that have at least one hydroxyl group in the molecule and

(a2) radically polymerizable unsaturated monomers given by the following formula ( )

wherein

Y is a group that contains radically polymerizable unsaturation and Z, p, R ¹ , R², h and a' are as defined above.

The curable composition according to claim 2, wherein the group Y that contains radically polymerizable unsaturation in the radically polymerizable unsaturated monomer given by formula ( ) is a group selected from the group consisting of acrylic group-containing organic groups and methacrylic group- containing organic groups given by the fol lowing general formulas

wherein

4

R is the hydrogen atom or a methyl group and R⁵ is a C ] _ i o alkylene group

wherein

4 5

R and R are defined as above, alkenylaryl group-containing organic groups given by the following general formula

wherein

R⁶ is the hydrogen atom or a methyl group,

7

R is a C i _ i o alkyl group,

R is a C ] _ ] o alkylene group, b is an integer from 0 to 4, and c is 0 or 1 , and 2- I O alkenyl groups.

The curable composition according to claim 2, wherein the copolymer (A) is obtained by the copolymerization additionally of at least one or more (a3) unsaturated monomer that does not contain the hydroxyl group in the molecule.

The curable composition according to claim 3 or 4, characterized in that the copolymer (A) is a copolymer provided by the copolymerization of the aforementioned unsaturated monomers (a l ) and (a2) and optional (a3) as constituent units thereof, wherein their mass ratios, taking the sum of the masses of the unsaturated monomers (a l ) to (a3) constituting the copolymer to be 1 00 mass parts, are in the range (a l ) : (a2) : (a3) = 0.5 - 50.0 : 0.5 - 50.0 : 0 - 99.0. 6. The curable composition according to any one of claims 1 to 5 , wherein the unsaturated monomer (a l ) constituting the copolymer (A) is at least one unsaturated monomer containing the hydroxyl group and selected from the group consisting of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate. 7. The curable composition according to claim 1 , wherein the curing agent is at least one (B l ) isocyanate compound.

8. The curable composition according to claim 1 or claim 7, wherein the

curing agent is at least one (B l -2) polyisocyanate compound.

9. The curable composition according to claims 1 to 8, wherein the molar equivalent for the NCO group in the curing agent (B) is in the range from 0. 1 to 2.0 per 1 equivalent of the hydroxyl group in the copolymer (A).

10. An article having a 0. 1 - to 1 0 μιη-thick cured layer provided by the cure of the curable composition according to any 1 of claims 1 to 9.

1 1. The article according to claim 10, that is a plate-shaped or sheet-shaped member.