More particularly, it relates to coating films, which retain water-and oil-repellency for a long term. The present invention also relates to a method for producing these coating films.

RELATED ART Among solvent-soluble fluorocarbon resins, fluorine- containing copolymers obtained by copolymerization of hydrocarbon monomers such as hydroxyalkyl vinyl ethers with fluoroolefins are commonly used. In coating materials of such fluorine-containing copolymers, hydrocarbon monomers constitute about 50% of the material for improved solubility of the material in an organic solvent. However, an increased content of hydrocarbon monomers causes a reduced content of fluorine in a fluorine-containing copolymer, resulting in a lack of desired coating film properties including water-and oil-repellency and stain resistance, which are required for fluorocarbon resins. On the other hand, water-and oil- repellency can be improved by addition of a small amount of an organosilicon compound such as silicone oil to a fluorine- containing copolymer. However, after such treatment, it is

difficult to retain water-and oil-repellency for a long term.

Moreover, in some applications, silicone oil cannot be used because it may leach from the surface of the coating.

The inventors of the present invention reported that a fluorine-containing copolymer comprising a specific type of organosilicon compound or reactive silicone could provide a coating film having excellent water-and oil-repellency, chemical resistance and weather resistance (see, e. g. , JP KOKAI 2000-313725, JP KOKAI 2001-247622, JP KOKAI 2001-288216).

However, it has not been clarified why these excellent properties are provided by a coating film formed from a fluorine-containing copolymer comprising such an organosilicon compound or reactive silicone. The inventors of the present invention have also found that when the amount of an organosilicon compound in a fluorine-containing copolymer falls within a specific range, such a copolymer can be used to form a coating film having still further improved water-and oil-repellency. However, it has also been remained unclear what characteristics of the resulting coating film are responsible for such an effect.

JP KOKAI 09-239913 discloses a film obtained by reaction of an alkyd resin, an amino resin or a modified silicone resin, along with its atomic concentrations of the film surface as measured by means of X-ray photoelectron spectroscopy (hereinafter referred to as"XPS"). However, there is no such information about a coating film formed from a fluorine- containing copolymer.

Thus, there is a need not only to clarify why a coating

film formed from a fluorine-containing copolymer has excellent properties, but also to provide further improvements in coating film properties so as to realize a coating film suitable for a wide variety of uses, including outdoor use where weather resistance is required and interior use where stain resistance is required.

DISCLOSURE OF THE INVENTION The object of the present invention is to provide a coating film formed from a fluorine-containing copolymer and its composition as well as a method for producing the coating film, in order to overcome the above problems. More particularly, the object of the present invention is to provide a coating film formed from a fluorine-containing copolymer and its composition, wherein the coating film has excellent stain resistance, water-repellency, oil-repellency, stain removability, chemical resistance and weather resistance, and exhibits only a small decrease in stain removability even after repeat of applying and removing stain. The object of the present invention is also to provide a method for producing the coating film above.

As a result of extensive research, the inventors of the present invention have found that a coating film exhibits markedly excellent properties when the coating film satisfies certain conditions in atomic concentrations of Si and F present at its surface. They have also found that such a coating film can be formed from a composition comprising a silicone- containing fluorocopolymer, and that such a coating film allows

Si atoms to be localized at its surface. These findings led to the completion of the present invention.

Namely, the problems stated above can be overcome by a coating film satisfying the following conditions (i) and (ii) as to the atomic concentrations of silicon and fluorine present at its surface: 2.1 s NA (Si (90°)) s 25. 8 (i) 2.0 s NA (F (90°)) 32. 7 (ii) [wherein NA (Si (6)) and NA (F (0)) denote the atomic concentrations (atomic ) of silicon and fluorine, respectively, as measured by X-ray photoelectron spectroscopy at a take-off angle 6].

The coating film of the present invention has a contact angle with water in a range from 98° to 110°. Its peel strength <BR> ranges from 10 g/50 mm to 1200 g/50 mm. Its film thickness ranges from 0.0001 mm to 0.5 mm.

The coating film of the present invention is provided on a substrate selected from the group consisting of acryl, wood, plastic, metal, graphite, paper, concrete, non-combustible material and glass. Such a substrate may be discharged or electrostatically charged.

The coating film of the present invention is formed from a composition comprising a silicone-containing fluorocopolymer (A) (hereinafter referred to as"fluorocopolymer composition").

Such a fluorocopolymer composition may further comprise an acrylic resin (B), a curing agent (C), a polymerization initiator (D), a solvent (E) or a combination thereof.

The silicone-containing fluorocopolymer (A) comprises

the following components as polymerization units: (a) a fluoroolefin; and (b) a silicone selected from the group consisting of a silicone of Formula (1) : R'-Si (CH3)2-O-[Si(CH3)2-O]n-Si(Ch3)2-R2 (1) (wherein R1 represents CH2=C(CH3)COO(CH2)r1-, CH2=CHCOO(CH2)r1- or CH2=CH-; r1represents an integer of 1 to 6; Ra represents a Cl-C,., alkyl group, CH2=C (CH3) COO (CHZ) r2-, CH2=CHCOO (CH2) rz-or CH2=CH- ; r2 represents an integer of 1 to 6; and n represents an integer of 20 to 150); a silicone of Formula (2): R3-Si [OSi (CH3)3]3 (2) (whereinR3represents CH2=C (CH3) COO (CH2)r3-, CH2=CHCOO(CH2)r3- or CH2=CH- ; r3 represents an integer of 1 to 6) ; a silicone of Formula (3): CH2=C(R4) Si (RS) (R6) (R') (3) (wherein R4 represents a hydrogen atom or a methyl group; and R5, R6 and R7, which may be the same or different, each represent a hydrogen atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a t-butyl group, a sec-butyl group, asubstitutedphenylgroup,-CF3,-C2H4CF3, -C(CH3)3 or -OSi(CH3)3) ; and a combination thereof, wherein the amounts of the fluoroolefin (a) and the silicone (b) are from 15% to 85% by mole and 0.001% to 6. 0% by mole, respectively, based on the sum of polymerization units.

The silicone-containing fluorocopolymer (A) may further comprise, as an additional polymerization unit, (c) an unsaturated monomer selected from the group consisting of a

hydroxy-containing unsaturated monomer, a hydroxy-free unsaturated monomer and a combination thereof, wherein the amount of the unsaturated monomer (c) is from 1% to 70% by mole, based on the sum of polymerization units.

Such a hydroxy-containing unsaturated monomer may be selected from the group consisting of: a monomer of Formula (9): CHR31=CR32-R33 (9) (wherein R31, R and R33, which may be the same or different, each represent a hydrogen atom, a hydroxy group, a Cl-C6 alkyl group, a C1-C6 alkenyl group, a C1-C6 hydroxyalkyl group, a C2-C6 hydroxyalkenyl group, a C1-C6 alkoxyl group, a Cl-C6 hydroxyalkyloxy group, a phenyl group or a substituted phenyl group, provided that at least one of R31, R32 and R33 is a hydroxy group or a hydroxy-containing group); a monomer of Formula (10): CHR34=CR35-X-OR36 (10) (wherein R34 and R35, which may be the same or different, each represent a hydrogen atom, a hydroxy group, a C1-C6 alkyl group, a Cl-C6 alkenyl group, a C1-C6 hydroxyalkyl group, a C2-C6 hydroxyalkenyl group, a C1-C6 alkoxyl group, a phenyl group or a substituted phenyl group; R36 represents a hydrogen atom, a C1-C6 alkyl group, a C1-C6 alkenyl group, a Cl-C6 hydroxyalkyl group, a Cl-C6 hydroxyalkenyl group, a phenyl group or a substituted phenyl group; and X represents a methylene group or a carbonyl group, provided that at least one of R34, R35 and R36O is a hydroxy group or a hydroxy-containing group); a monomer of Formula (11) :

CHR37=CR38-OR39 (11) (wherein R and R, which may be the same or different, each represent a hydrogen atom, a hydroxy group, a Cl-C6 alkyl group, a C1-C6 alkenyl group, a Cl-C6 hydroxyalkyl group, a Ca-C6 hydroxyalkenyl group, a Cl-C6 alkoxyl group, a phenyl group or a substituted phenyl group; R39 represents a hydrogen atom, a Cl-C6 alkyl group, a C1-C6 alkenyl group, a Cl-C6 hydroxyalkyl group, a Cl-C6 hydroxyalkenyl group, a phenyl group or a substituted phenyl group; and X represents a methylene group or a carbonyl group, provided that at least one of R3', R38 and R390 is a hydroxy group or a hydroxy-containing group) ; and a combination thereof. The amount of the hydroxy- containing unsaturated monomer is from 1% to 50% by mole, based on the sum of polymerization units.

The silicone-containing fluorocopolymer (A) may be a copolymer formed by reaction between an unsaturated isocyanate and a silicone-containing fluorocopolymer comprising such a hydroxy-containing unsaturated monomer as a polymerization unit.

The silicone (b) as a polymerization unit of the silicone-containing fluorocopolymer (A) may be selected from the group consisting of: a silicone of Formula (4): CH2=C (CH3) COOC3H6-Si (CH3) 2-O- [Si (CH3) 2-O] p-Si (CH3) 2-R21 (4) (wherein R"represents a C1-C12 alkyl group or CH2=CH- ; and p represents an integer of 25 to 150); a silicone of Formula (5): CH2=CHCOOC3H6-Si (CH3) 2-O- [Si (CH3) 2-O] s-Si (CH3) 2-R22 (5)

(wherein R22 represents a Cl-Cl2 alkyl group or CH2=CH- ; and s represents an integer of 25 to 150); a silicone of Formula (6): R23_Si (CH3)2-O- [Si(CH3)2-O]q-Si(CH3)2-R24 (6) (wherein R23 and R24, which may be the same or different, each represent CH2=C (CH3)COO(CH2)3- or CH2=CHCOO(CH2)3- ; and q represents an integer of 20 to 150); a silicone of Formula (7): CH2=CH-Si (CH3) 2-0- [Si (CH3) 2-0] y-Si (CH3) 2-R25 (7) (wherein R25 represents a Cl-Cl2 alkyl group or CH2=CH- ; and y represents an integer of 25 to 150); a silicone of Formula (8): CH2=C (R 26) COOC 3H6-S' [OSi (CH3) 313 (8) (wherein R26 represents a hydrogen atom or a methyl group); and a combination thereof.

The problems stated above can also be overcome by a method for producing a coating film satisfying the following conditions (i) and (ii) as to the atomic concentrations of silicon and fluorine present at its surface: 2.1 NA (Si (90°)) S 25. 8 (i) 2.0 NA (F (90°)) 32. 7 (ii), which comprises the steps of applying a composition comprising the silicone-containing fluorocopolymer (A) onto a substrate and curing the composition. The step of curing the composition may be accomplished by means of cold curing, heat curing, photocuring, electron radiation curing or a combination thereof.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below.

In the present invention, atomic concentrations at a surface of a coating film are determined by X-ray photoelectron spectroscopy (XPS). Measurement conditions for XPS are as described in Example 1 below.

In general, since XPS allows the investigation of elements present near the sample surface and surrounding environments of the elements, XPS is used for qualitative and quantitative analyses. Typically, XPS enables the analysis of elements present at a depth of several nm to several tens of nm below the sample surface.

In XPS, the detection depth from the sample surface can be changed by varying the take-off angle 0 (i. e. , the angle between the sample surface and the analyzer axis). This is because the effective escape depth (L) of photoelectrons (the actual distance required for photoelectrons to pass through a sample before reaching an analyzer) depends on 0 and hence differs from the escape depth (Lo) (the minimum distance between the sample surface and the position where photoelectrons are released), as explained below. Namely, L is represented by the following equation: L = Lo/sin 0 and L increases with decrease in 0. A higher value of L increases the probability that photoelectrons lose their energy due to interaction with the sample, thus increasing the percentage of released photoelectrons that do not contribute to peaks in the

XPS spectrum. As a result, a higher value of L reduces the actually detectable depth of the sample and hence provides information concerning a portion of the sample closer to the surface.

As used herein, the atomic concentration of element X measured by XPS at a take-off angle 8 is expressed as NA (X (6)) (atomic %). Elements Si, F, C and O are used for calculation of atomic concentrations, and the sum of these elements is set to 100%. Namely, when the amount of element X measured by XPS at a take-off angle 0 is expressed as A (X (6)), NA (X (6)) is represented as follows: NA (X (0)) = A (X (#))/(A (Si (0)) +A (F (#)) +A (C (0)) +A (O (#))) x 100.

By way of example, NA (Si (6)) and NA (F (0)) are represented as follows: NA (Si (0)) = A (Si(#))/(A(Si(#)) +A (F (#)) +A (C (e)) +A (0 (#))) x 100 (I) NA (F (0)) = A (F (#))/(A(Si(#)) +A (F (#)) +A (C (#)) +A (0 (#))) x 100 (II).

In the present invention, water-repellency is evaluated by contact angle with water, oil-repellency is evaluated by oil ink repellency, and stain removability is evaluated by oil ink removability and/or peel strength. Measurement procedures and conditions for contact angle with water, oil ink repellency, oil ink removability and peel strength are as shown in Example 1 below.

In the coating film of the present invention, the atomic concentration of Si [NA (Si (90°)) (atomic %)] present at its surface is at least 2.1 atomic % and at most 50 atomic, preferably at most 30 atomic %, more preferably at most 25.8

atomic %. Below the above range, oil ink removability and oil ink repellency are reduced, and the resulting coating film is also less water-repellent. Beyond the above range, there is a need to handle a Si-rich composition in the production of coating films, but such a composition is difficult to handle.

In the coating film of the present invention, the atomic concentration of F [NA (F (90°)) (atomic %)) present at its surface is at least 1.0 atomic %, preferably at least 2.0 atomic %, and at most 50.0 atomic %, preferably at most 32.7 atomic %.

NA (F (90°)) below the above range results in insufficient water-repellency, oil-repellency and stain removability.

NA (F (90°)) beyond the above range results in reduced oil- repellency and stain removability.

The coating film of the present invention desirably satisfies the following conditions (i) and (ii) as to NA (Si (90°)) and NA (F (90°)) : 2.1 NA (Si (90°)) s 25. 8 (i) 2.0 s NA (F (90°)) 32. 7 (ii).

NA (Si (90°))/NA (F (90°)) is at least 0.063 and at most 20.0, preferably at most 12.0, more preferably at most 11.4. If NA (Si (90°))/NA (F (90°)) does not fall within the above range, the resulting coating film may have insufficient water-repellency, oil-repellency and stain removability.

More preferably, the coating film of the present invention further satisfies the following conditions (v) and (vi) as to the concentrations of Si and F at its surface, as measured by XPS: NA (Si (90°)) < NA (Si (45°)) < NA (Si (20°)) (v)

NA (F (90°)) > NA (F (45°)) > NA (F (20°)) (vi).

As stated above, the results of XPS analysis provide information concerning a portion of the sample closer to the surface at a lower take-off angle0, whereas XPS results reflect information concerning a portion deeper from the sample surface when measured at a higher take-off angle 0. Thus, the condition (v) indicates that Si is localized near the surface, while the condition (vi) indicates that the concentration of F increases with receding from the surface. Namely, the coating film of the present invention is characterized by the in-depth distributions of Si and F. Without being bound by any theory, it is believed that such in-depth distributions of Si and F contribute to excellent properties (e. g. , water-repellency, oil-repellency, stain resistance) found for the coating film of the present invention.

The coating film of the present invention has a contact angle with water of 90° to 120°, preferably 98° to 120°, and more preferably 98° to 110° ; it has excellent water-repellency.

The coating film of the present invention has a peel strength of at least 10 g/50 mm, preferably at least 25 g/50 mm, more preferably at least 27 g/50mm, and at most 1200 g/50 mm, preferably at most 1000 g/50 mm, more preferably at most 300 g/50 mm, still more preferably at most 200 g/50 mm. Namely, the coating film of the present invention has excellent stain removability.

The coating film of the present invention has an average film thickness of at least 0. 00005 mm, preferably at least 0. 0001 mm, more preferably at least 0.0002 mm, and at most 2 mm,

preferably at most 0.5 mm, more preferably at most 0.3 mm. If the coating film is too thin, some areas cannot be coated completely. Likewise, a too thick film is less economic because there is no great difference in its properties.

Any substrate, whether organic or inorganic, may be used for the coating film of the present invention. Examples of a substrate material available for use include wood, plastic (e. g., acryl, PET), FRP, metals (e. g. , aluminum, copper, zinc, nickel), graphite, paper, concrete, non-combustible materials (e. g., ceramics such as plasterboards, calcium silicate boards and flexible boards) and glass. Preferred transparent materials are acryl, PET and glass.

Such a substrate may take any form, with either flat or rough surface. Articles having the coating film of the present invention may be used for a wide variety of interior and/or outdoor uses.

Prior to formation of the coating film, a substrate may be discharged or electrostatically charged. Examples of electrostatically charging treatment include positively charging treatment, and examples of discharging treatment include corona discharge treatment. The in-depth distributions of elements (especially Si and F) in the coating film are influenced by corona discharge treatment or positively charging treatment performed on the substrate prior to coating film formation. More specifically, Si is localized at the surface and the concentration of F increases with receding from the surface. It is therefore preferable to perform the above treatment on a substrate before forming the coating film of the

present invention. In addition to the corona discharge treatment or the positively charging treatment, a substrate may be subject to any other treatment, as long as it ensures that Si is localized at the surface and the concentration of F increases with receding from the surface.

Before forming the coating film of the present invention, a substrate may be coated with an additional coating film. In such a case, the coating film of the present invention serves as a topcoat. Even when serving as a topcoat, the coating film of the present invention also exhibits excellent properties as mentioned above. After a substrate is pre-coated with an additional coating film, the above-mentioned corona discharge treatment or positively charging treatment may be performed on the pre-coated substrate, followed by formation of the coating film of the present invention.

The coating film of the present invention is formed from a composition comprising a silicone-containing fluorocopolymer (A) (hereinafter referred to as"fluorocopolymer composition").

The fluorocopolymer composition may further comprise an acrylic resin (B), a curing agent (C), a polymerization initiator (D), a solvent (E) or a combination thereof. The fluorocopolymer composition is applied onto a substrate and then cured to form the coating film of the present invention. Curing may be accomplished in any known manner, including cold curing, heat curing, photocuring (e. g. , ultraviolet curing) and electron radiation curing. As used herein, cold curing is intended to mean that the composition is cured at ambient temperature without heating.

The silicone-containing fluorocopolymer (A) comprises (a) a fluoroolefin and (b) a silicone as polymerization units.

The silicone-containing fluorocopolymer (A) may further comprise (c) an unsaturated monomer as an additional polymerization unit. These polymerization units will be described below.

Any fluoroolefin may be used as a polymerization unit (a), but preferred are CH2=CHF, CH2=CF2, CHF=CHF, CHF=CF2, CF2=CF2, CF2=CFC1 and CF2=CF (CF3), and more preferred are CF2=CF2 and/or <BR> <BR> <BR> <BR> <BR> CH2=CF2. Amixtureofseveralfluoroolefinsmaybeusedforthis purpose.

In order to satisfy the above-mentioned conditions as to NA (Si (0)) and NA (F (H)), the amount of the fluoroolefin (a) is at least 10% by mole, preferably at least 12% by mole, more preferably at least 15% by mole, still more preferably at least 25 % by mole, and at most 90% by mole, preferably at most 85% by mole, more preferably at most 80% by mole, based on the sum of polymerization units in the silicone-containing fluorocopolymer (A).

Examples of the silicone (b) include those having the following Formulae (1) to (3) and combinations thereof: Rl-Si (CH3)2-O-[Si(CH3)2-O]n-Si(CH3)2-R2 (1) [wherein R1 represents Rll (CH2) rl (wherein R"represents an unsaturated carboxyl group) or an alkenyl group, preferably <BR> <BR> <BR> <BR> <BR> represents CH2=C (CH3) COO (CH2) r1-, CH2=CHCOO (CH2) r1-or CH2=CH-; r represents an integer of 1 to 6, preferably =3 ; Ra represents a C1-C12 alkyl group, a C1-C12 alkenyl group or R12 (CH2) r2- (wherein R12 represents an unsaturated carboxyl group), preferably

represents a C1-Cl2 alkyl group, CH, =C (CH3) COO (CH2)r2-, CH2=CHCOO (CH2) r2- or CH2=CH- ; r2 represents an integer of 1 to 6, preferably r2 = 3; and n represents an integer of 20 to 150] ; R3-Si [OSi (CH3)3]3 (2) [wherein R3 represents CH2=C(CH3)COO(CH2)r3-, CH2=CHCOO(CH2)r3- or CH2=CH- ; r3 represents an integer of 1 to 6, preferably r3 = 3] ; and CH2=C (R4) Si (R5) (R6) (R7) () [wherein R4 represents a hydrogen atom or a C1-C4 alkyl group, preferably represents a hydrogen atom or a methyl group; and R5, R and R, which may be the same or different, each represent a Cl-C6 alkyl group, a Cl-C6 alkenyl group, an aryl group, a substituted aryl group, a heterocyclic group, a fluoroalkyl group or a trialkylsiloxy group, preferably represent a hydrogen atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a t-butyl group, a sec-butyl group, aphenylgroup, asubstitutedphenylgroup,-CF3,-C2H4CF3, -C(CH3)3 or -OSi(CH3)3].

Preferred examples of the silicone (b) include polydimethylsiloxane, one or both ends of which are methacryl-modified, acryl-modified or vinyl-modified.

As used herein, a"reactive silicone"refers to a silicone having an unsaturated bond (s) on one or both ends, including the methacryl-modified, the acryl-modified or the vinyl- modified polydimethylsiloxane as described above.

More preferably, the silicone (b) is selected from those having any of the following Formulae (4) to (8) or combinations thereof:

CH2=C(CH3)COOC3H6-Si(CH3)2-O-[Si(CH3)2-O]p-Si(CH3)2-R21 (4) (wherein R21 represents a C1-C12 alkyl group or CH2=CH-; and p represents an integer of 25 to 150); CH2=CHCOOC3H6-Si(CH3)2-O-[Si(CH3)2-O]s-Si(CH3)2-R22 (5) (wherein R22 represents a C1-Cl2 alkyl group or CH2=CH-; and s represents an integer of 25 to 150) ; R"-Si (CH3)2-O-[Si(CH3)2-O]q-Si(CH3)2-R24 (6) (wherein R and R, which may be the same or different, each represent CH2=C (CH3) COO (CH2) 3-or CH2=CHCOO (CH2) 3-; and q represents an integer of 20 to 150) ; CH2=CH-Si(CH3)2-O-[Si(CH3)2-O]y-Si(CH3)2-R25 (7) (wherein R25 represents a Ci-C12 alkyl group or CH2=CH- ; and y represents an integer of 25 to 150); and CH2=C (R26) COOC3H6-Si [OSi (CH3) 3] 3 (8) (wherein R26 represents a hydrogen atom or a methyl group).

These reactive silicones may be used either alone or in combination. These reactive silicones preferably have a number average molecular weight of 200 to 30,000. When the number average molecular weight falls within the above range, the resulting coating film satisfies the above-mentioned conditions as to NA (Si (0)) and NA (F (0)) and easily attain excellent coating film properties.

The amount of the silicone (b) is at least 0. 001% by mole, preferably at least 0. 01% by mole, more preferably at least 0. 02% by mole, even more preferably at least 0.03% by mole, and at most 20% by mole, preferably at most 10% by mole, more preferably at most 6.0% by mole, still more preferably at most 2. 0% by mole, even more preferably at most 1. 0% by mole, based on the sum of

polymerization units in the silicone-containing fluorocopolymer. When the amount of the silicone (b) falls within the above range, the resulting coating film satisfies the above-mentioned conditions as to NA (Si (0)) and NA (F (#)) and easily attain excellent coating film properties.

The unsaturated monomer (c) contained in the silicone-containing fluorocopolymer (A) may be an unsaturated monomer containing a hydroxy group (s) (hereinafter referred to as"hydroxy-containing unsaturated monomer"), an unsaturated monomer free from hydroxy groups (hereinafter referred to as "hydroxy-free unsaturated monomer") or a combination thereof.

The unsaturated monomer serves to increase the solubility in a solvent. A hydroxy-containing unsaturated monomer is involved in cross-linking reactions during the curing step of coating films and serves to accelerate the curing process.

Examples of a hydroxy-containing unsaturated monomer include those having any of the following formulae: CHR3l=cR32-R33 (9) (wherein R31, R and R33, which may be the same or different, each represent a hydrogen atom, a hydroxy group, a Cl-C6 alkyl group, a Cl-C6 alkenyl group, a Cl-C6 hydroxyalkyl group, a C2-C6 hydroxyalkenyl group, a C1-C6 alkoxyl group, a Cl-C6 hydroxyalkyloxy group, a phenyl group or a substituted phenyl group, provided that at least one of R31, R and R33is a hydroxy group or a hydroxy-containing group); and CHR34=CR35-X-OR36 (10) (wherein R34 and R35, which may be the same or different, each represent a hydrogen atom, a hydroxy group, a Cl-C6 alkyl group,

a C1-C6 alkenyl group, a Cl-C6 hydroxyalkyl group, a C2-C6 hydroxyalkenyl group, a C1-C6 alkoxyl group, a Cl-C6 hydroxyalkyloxy group, a phenyl group or a substituted phenyl group; R36 represents a hydrogen atom, a C1-C6 alkyl group, a Cl-C6 alkenyl group, a Cl-C6 hydroxyalkyl group, a C2-C6 hydroxyalkenyl group, a phenyl group or a substituted phenyl group; and X represents a methylene group or a carbonyl group, provided that at least one of R34, R35 and R36O is a hydroxy group or a hydroxy-containing group); and a monomer of Formula (11) : CHR37=CR38-OR39 (11) (wherein R and R, which may be the same or different, each represent a hydrogen atom, a hydroxy group, a Ci-Cg alkyi group, a Cl-C6 alkenyl group, a Cl-C6 hydroxyalkyl group, a Ca-C6 hydroxyalkenyl group, a C1-C6 alkoxyl group, a phenyl group or a substituted phenyl group; R39 represents a hydrogen atom, a Cl-C6 alkyl group, a Cl-C6 alkenyl group, a Ci-Cg hydroxyalkyl group, a Ca-C6 hydroxyalkenyl group, a phenyl group or a substituted phenyl group; and X represents a methylene group or a carbonyl group, provided that at least one of R37, R38 and R390 is a hydroxy group or a hydroxy-containing group); and a combination thereof.

A Cl-C6 hydroxyalkyl group in Formulae (9), (10) and (11) preferably has a hydroxy group at its end, as represented by -(CH2)x-OH (wherein x represents an integer of 2 to 6).

Examples of such a hydroxy-containing unsaturated monomer include hydroxybutyl vinyl, hydroxybutyl vinyl ether (e. g. , 4-hydroxybutyl vinyl ether), hydroxypropyl vinyl,

hydroxypropyl vinyl ether (e. g. , 3-hydroxypropyl vinyl ether), hydroxyethyl vinyl ether (e. g. , 2-hydroxyethyl vinyl ether), 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 2-hydroxyethyl acrylate, 2- hydroxypropyl acrylate and 2-hydroxybutyl acrylate. Among them, preferred is 4-hydroxybutyl vinyl ether. These hydroxy-containing unsaturated monomers may be used either alone or in combination.

Examples of a hydroxy-free unsaturated monomer include olefins such as ethylene and propylene, as well as esters between saturated carboxylic acids and vinyl alcohols, such as vinyl acetate, vinyl n-butyrate, vinyl isobutyrate and vinyl propionate. Examples further include monomers represented by Formula (9), (10) or (11), provided that they are free from hydroxy groups.

In a case where a combination of a hydroxy-containing unsaturated monomer (s) and a hydroxy-free unsaturated monomer (s) is used as an unsaturated monomer (c), the hydroxy-containing unsaturated monomer may have a structure where a hydrogen atom (s) of the corresponding hydroxy-free unsaturated monomer is replaced with a hydroxy group (s). For example, hydroxybutyl vinyl ether may be used as a hydroxy- containing unsaturated monomer, and butyl vinyl ether may be used as a hydroxy-free unsaturated monomer.

The amount of the unsaturated monomer (c) is at least 1% by mole, preferably at least 5% by mole, more preferably at least 10% by mole, and at most 70% by mole, preferably at most 50% by mole, more preferably at most 40% by mole, even more

preferably at most 30% by mole, based on the sum of polymerization units in the silicone-containing fluorocopolymer (A). If the amount of the unsaturated monomer (c) exceeds the above range, it is difficult to achieve properties including water-repellency and oil-repellency. If the amount of the unsaturated monomer (c) is below the above range, the silicone-containing fluorocopolymer (A) may have reduced solubility in a solvent.

The amount of a hydroxy-containing unsaturated monomer is at least 1% by mole, preferably at least 5% by mole, more preferably at least 10% by mole, and at most 50% by mole, preferably at most 30% by mole, more preferably at most 25% by mole, based on the sum of polymerization units in the silicone-containing fluorocopolymer (A). If the amount of a hydroxy-containing unsaturated monomer exceeds the above range, it is difficult to achieve properties including water- repellency and oil-repellency. If the amount of a hydroxy- containing unsaturated monomer is below the above range, it may be difficult to provide cured coating films.

The silicone-containing fluorocopolymer (A) preferably has an unsaturated bond (s) such as a double bond. This is because such unsaturated bonds are involved in polymerization and/or cross-linking between molecules of the silicone- containing fluorocopolymer (A) as well as between the silicone-containing fluorocopolymer (A) and other components during the curing step, and hence they serve to accelerate the curing process. As a result, the amount of the curing agent (C) can be reduced.

Such unsaturated bonds may be those remaining unreacted after polymerization of the silicone-containing fluorocopolymer (A) or may be introduced after the polymerization.

In a case where the silicone-containing fluorocopolymer (A) comprises a hydroxy-containing unsaturated monomer, its hydroxy group (s) may be reacted with a compound having an unsaturated bond (s) to introduce an unsaturated bond (s) into the silicone-containing fluorocopolymer (A). A compound to be reacted with a hydroxy group may be an unsaturated isocyanate having an unsaturated bond (s) and an isocyanate group (s).

Examples of such an unsaturated isocyanate include 2-isocyanato ethyl methacrylate, 2-isocyanato ethyl acrylate, 4-isocyanato butyl methacrylate, 4-isocyanato butyl acrylate, a reaction product between an unsaturated monoalcohol (1 mole) and a diisocyanate compound (1 mole), and a reaction product between an unsaturated monoalcohol (2 moles) and a triisocyanate compound (1 mole). Examples of such an unsaturated monoalcohol include hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxybutyl methacrylate, hydroxybutyl acrylate and allyl alcohol.

The fluorocopolymer composition comprising the silicone-containing fluorocopolymer (A) may further comprise an acrylic resin (B), a curing agent (C), a polymerization initiator (D), a solvent (E) or a combination thereof.

In a case where the fluorocopolymer composition comprises an acrylic resin (B) and/or a curing agent (C), the

amount of the silicone-containing fluorocopolymer (A) is at least 5% by weight, preferably at least 20% by weight, more <BR> <BR> <BR> <BR> <BR> <BR> <BR> preferably at least 30% by weight, still more preferably at least 40% by weight, and at most 95% by weight, preferably at most 80% by weight, more preferably at most 70% by weight, still more preferably at most 60% by weight, based on the sum of the silicone-containing fluorocopolymer (A), the acrylic resin (B) and the curing agent (C).

In a case where the fluorocopolymer composition comprises a curing agent (C) and/or a polymerization initiator (D), the amount of the silicone-containing fluorocopolymer (A) is at least 5% by weight, preferably at least 10% by weight, more preferably at least 25% by weight, still more preferably at least 40% by weight, and at most 95% by weight, preferably at most 85% by weight, more preferably at most 75% by weight, still more preferably at most 60% by weight, based on the sum of the silicone-containing fluorocopolymer (A), the curing agent (C) and the polymerization initiator (D).

Components other than the silicone-containing fluorocopolymer (A) will be described below.

An acrylic resin (B) refers to a polymer or copolymer of acrylic acid, methacrylic acid or derivatives thereof, including thermosetting acrylic resins and photocurable acrylic resins. Thermosetting acrylic resins are preferred in the case of using heat curing in the curing step, while photocurable acrylic resins are preferred in the case of using photocuring such as ultraviolet curing. These acrylic resins may be used either alone or in combination.

Illustrative examples of an acrylic resin (B) include those commonly called acrylic resins, such as methyl (meth) acrylate copolymers, ethyl (meth) acrylate copolymers, butyl (meth) acrylate copolymers, styrene-containing (meth) acrylate copolymers and hydroxyethyl (meth) acrylate copolymers. The term" (meth) acrylate" is intended to mean both acrylate and methacrylate.

Examples of commercially available acrylic resins include Acrydic A-814, Acrydic A-810-45 (Dainippon Ink & Chemicals, Inc. , Japan), Tesloid 4211-46, Tesloid 4212-46 (Hitachi Kasei Polymer, Co. , Ltd. , Japan), Dianal LR-620, Dianal LR-199, Dianal LR-2516, Dianal SS-792 (Mitsubishi Rayon Co., Ltd. , Japan), Hitaloid 3046C and Hitaloid 3018 (Hitachi Chemical Co. , Ltd. , Japan), each of which may be used for the present invention.

Examples of photocurable acrylic resins include photocurable (meth) acrylate resins, such as commonly known aliphatic/aromatic urethane (meth) acrylates, epoxy (meth) acrylates, polyester (meth) acrylates and polyether (meth) acrylates.

Illustrative examples include aromatic and aliphatic urethane acrylates such as Ebecryl 210, Ebecryl 8402 and Ebecryl 1290K (Daicel-UCB Co. , Ltd. ) ; epoxy acrylates such as KAYARAD EAM-2300, KAYARAD R-190 (Nippon Kayaku Co. , Ltd. , Japan) and Ebecryl 600 (Daicel-UCB Co., Ltd.) ; and polyester acrylates such as Ebecryl 80, Ebecryl 800, Ebecryl 810 (Daicel-UCB Co., Ltd.) and Aronix M-7100 (Toagosei Co. , Ltd. , Japan). These photo-crosslinkable (meth) acrylate resins may be used either

alone or in combination.

In a case where the fluorocopolymer composition comprises the acrylic resin (B), the amount of the acrylic resin (B) is at least 5% by weight, preferably at least 20% by weight, <BR> <BR> more preferably at least 40% by weight, and at most 95% by weight, preferably at most 85% by weight, more preferably at most 60% by weight, based on the sum of the silicone-containing fluorocopolymer (A), the acrylic resin (B) and the curing agent (C). The use of the acrylic resin (B) may improve properties of coating films, such as lifetime and hardness.

Any substance may be used as a curing agent (C), as long as it can accelerate curing of the fluorocopolymer composition.

Examples include substances which are polymerizable and/or cross-linkable with the silicone-containing fluorocopolymer (A).

When a composition comprising the silicone-containing fluorocopolymer (A) is cold-cured, the curing agent (C) preferably comprises polyvalent isocyanates. A"polyvalent isocyanate"refers to a compound having two or more isocyanate groups.

Preferred examples of polyvalent isocyanates include non-yellowing diisocyanates or adducts thereof (e. g., hexamethylene diisocyanate, isophorone diisocyanate); triisocyanates such as lysine triisocyanate (e. g. , 2- isocyanatoethyl-2,6-diisocyanatohexanoate) ; and polyvalent isocyanates having isocyanurates. Among them, preferred are triisocyanates (e. g. , lysine isocyanate) and polyvalent isocyanates having isocyanurates. In a case where cold curing

is performed in the presence of isocyanates, the curing process may be accelerated by addition of a known catalyst such as dibutyltin dilaurate. These polyvalent isocyanates may also be used for heat curing.

Examples of a curing agent for heat curing of the fluorocopolymer composition include a melamine curing agent, a urea resin curing agent and a polybasic acid curing agent.

Examples of such a melamine curing agent include butylated melamine, methylated melamine and epoxy-modified melamine; the degree of modification may be selected as appropriate for the intended use, and the degree of self-condensation may also be appropriately selected. Examples of a urea resin curing agent include methylated urea resins and butylated urea resins.

Examples of a polybasic acid curing agent include long chain aliphatic dicarboxylic acids, aromatic polyvalent carboxylic acids and acid anhydrides thereof.

A reactive diluent may also be used as a curing agent (C). As used herein, a"reactive diluent"refers to a compound which not only serves as a solvent, but also is involved in cross-linking reactions during the curing step and hence incorporated into the resulting coating film. Thus, a reactive diluent may be used instead of or in addition to a solvent. When compared to using an organic solvent, such an embodiment is advantageous in reducing the amount of an organic solvent released into the atmosphere. Further, because of its low viscosity, a reactive diluent allows reduction in the viscosity <BR> <BR> <BR> <BR> <BR> <BR> <BR> of the fluorocopolymer composition, resulting in an improvement in workability. Due to these properties, a reactive diluent

can be used in all curing techniques.

A reactive diluent may be monofunctional, bifunctional or multifunctional. A reactive diluent preferably has an unsaturated double bond (s) in its molecule. For example, a monofunctional acrylate or methacrylate, a bifunctional (meth) acrylate, a trifunctional (meth) acrylate, or a tetra-or higher functional (meth) acrylate may be used.

Illustrative examples of a reactive diluent include one or more members selected from the group consisting of acrylate compounds, methacrylate compounds and ethers as listed below.

Examples of a monofunctional acrylate include isobutyl (meth) acrylate, t-butyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, cyclohexyl (meth) acrylate, isobonyl (meth) acrylate, benzyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethylcarbitol (meth) acrylate, 2- ethylhexylcarbitol (meth) acrylate, phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-acryloyloxyethyl-2-hydroxypropylphthalate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-acryloyloxyethyl hydrogen phthalate, 2-acryloyloxypropyl hydrogen phthalate, dimethylaminoethyl (meth) acrylate, (3-carboxyethyl (meth) acrylate, isobonyl (meth) acrylate, oxyethylated phenol acrylate, phenol EO-modified (meth) acrylate, paracumylphenol EO-modified (meth) acrylate and nonylphenol EO-modified (meth) acrylate.

Likewise, examples of a bifunctional acrylate include 1,6-hexanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1, 9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, bisphenol A EO-modified di (meth) acrylate and isocyanuric acid EO-modified di (meth) acrylate.

Illustrative examples of trifunctional (meth) acrylate monomers include pentaerythritol triacrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytriacrylate, trimethylolpropane EO-modified triacrylate, trimethylolpropane PO-modified triacrylate and isocyanuric acid EO-modified triacrylate.

Illustrative examples of a tetra-or higher functional (meth) acrylate include ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate.

In a case where the fluorocopolymer composition comprises the curing agent (C), the amount of the curing agent (C) is at least 0. 1% by weight, preferably at least 5% by weight, and at most 40% by weight, preferably at most 30% by weight, based on the sum of the silicone-containing fluorocopolymer (A), the acrylic resin (B) and the curing agent (C). If the amount of the curing agent is below the above range, the curing agent fails to provide sufficient acceleration of the curing process.

If the amount of the curing agent exceeds the above range, it is difficult to achieve sufficient water-repellency and

oil-repellency.

In a case where the fluorocopolymer composition comprises a curing agent (C) including a reactive diluent, and a polymerization initiator (D), the amount of the silicone- containing fluorocopolymer (A) is at least 5% by weight, preferably at least 10% by weight, more preferably at least 25% by weight, still more preferably at least 40% by weight, and at most 95% by weight, preferably at most 85% by weight, more preferably at most 75% by weight, still more preferably at most 60% by weight, based on the sum of the silicone-containing fluorocopolymer (A), the curing agent (C) including the reactive diluent, and the polymerization initiator (D).

In a case where the fluorocopolymer composition comprises a photocurable acrylic resin and the curing agent (C), <BR> <BR> the total amount of the photocurable acrylic resin and the curing agent is at least 1% by weight, preferably at least 5% by weight, more preferably at least 10 wt% by weight, still more preferably at least 20 wt% by weight, and at most 90% by weight, preferably at most 85% by weight, more preferably at most 65% by weight, still more preferably at most 50% by weight, based on the sum of the silicone-containing fluorocopolymer (A), the acrylic resin (B) and the curing agent (C).

The fluorocopolymer composition may comprise a polymerization initiator (D). A polymerization initiator encompasses a photopolymerization initiator and a thermal polymerization initiator, which may be selected as appropriate for curing techniques.

Examples of a thermal polymerization initiator available

for use include benzoyl peroxide, azobisisobutyronitrile, t-butylperoxy-2-ethylhexanoate and t-butylperoxyisopropyl monocarbonate.

Examples of a photopolymerization initiator available for use in ultraviolet curing include benzoin ether, benzophenone, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl- 1- [4- (methylthio) phenyl]-2-morpholinopropan-1-one, 2- benzyl-2-dimethylamino-l- (4-morpholinophenyl)-butanone- 1, 2, 2-dimethoxy-1, 2-diphenylethan-l-one and 1-hydroxy- cyclohexyl-phenyl-ketone.

Mixing between at least one silicone-containing fluorocopolymer and at least one member selected from the group consisting of the acrylic resin (B), the curing agent (C) and the polymerization initiator (D) may be accomplished in various devices used for standard coating preparation, such as a ball mill, a paint shaker, a sand mill, a triple roll mill and a kneader. In this step, other substances such as pigments, dispersion stabilizers, viscosity adjusters and leveling agents may further be mixed and incorporated into the coating composition, if necessary.

The fluorocopolymer composition may comprise a solvent (E). Examples of a solvent include aromatic hydrocarbons (e. g. , xylene, toluene), acetic esters (e. g. , ethyl acetate, butyl acetate), ketones (e. g. , methyl ethyl ketone, methyl isobutyl ketone), glycol ethers (e. g. , ethyl cellosolve), alcohols (e. g. , butanol) and commercially available thinners.

Particularly preferred examples include butyl acetate, ethyl acetate, toluene, xylene, an aromatic hydrocarbon mixture,

methyl ethyl ketone, methyl isobutyl ketone, methanol, butanol, isopropyl alcohol, ethanol and Solvesso@. These solvents may be used either alone or in combination.

In a case where the fluorocopolymer composition comprises a curing agent (C) including a reactive diluent and a solvent (E), the amount of the silicone-containing fluorocopolymer (A) is at least 5% by weight, preferably at least 20% by weight, more preferably at least 30% by weight, still <BR> <BR> <BR> <BR> <BR> <BR> <BR> more preferably at least 40% by weight, and at most 95% by weight, preferably at most 85% by weight, more preferably at most 75% by weight, still more preferably at most 60% by weight, based on the sum of the silicone-containing fluorocopolymer (A), the curing agent (C) including the reactive diluent, and the solvent (E).

The coating film of the present invention is formed by applying the above fluorocopolymer composition onto a substrate and then curing the composition. The curing step may be accomplished by means of any known curing technique, including cold curing, heat curing, ultraviolet curing and electron radiation curing.

When cold-cured, the fluorocopolymer composition preferably comprises a polyvalent isocyanate as a curing agent (C), as stated above.

Conditions for heat curing may be selected as appropriate for the silicone-containing fluorocopolymer (A) and the curing agent (C). For example, in a case where an isocyanate compound is used as a curing agent (C), the heating temperature is preferably set in a range from 40°C to 80°C, and the heating time

is preferably set in a range from 1 to 24 hours. In a case where a melamine or a blocked isocyanate is used, the heating temperature is preferably set in a range from 140°C to 230°C, while the heating time is preferably set in a range from 1 to 20 minutes.

Ultraviolet curing may be accomplished in a known manner.

For example, it can be accomplished using a high-pressure mercury lamp under conditions of 100 to 1000 mJ/cm2. When UV-cured, the fluorocopolymer composition preferably comprises a photopolymerization initiator.

Electron radiation curing may be accomplished in a known manner. Electron radiation curing is advantageous in curing the fluorocopolymer composition in the absence of a polymerization initiator. Curing conditions are set to, e. g., 30 kGy at 110 kV or 30 kGy at 200 kV.

The present invention will be further described in the following Examples, which are not intended to limit the scope of the invention. Based on the detailed description, various changes and modifications will be apparent to those skilled in the art, and such changes and modifications fall within the scope of the invention.

EXAMPLES [Example 1] A 1L autoclave equipped with a stainless-steel stirrer (resistant up to 10 MPa) was charged with vinylidene fluoride/ tetrafluoroethylene/hydroxybutyl vinyl ether/butyl vinyl ether/a reactive silicone I (Mw = ca. 5000) at a molar ratio

of 30/40/15/14. 97/0. 03 as well as butyl acetate as a polymerization solvent and t-butyl peroxypivalate as a polymerization initiator. After the internal temperature was elevated to 60°C with stirring, the reaction was continued with stirring and stopped after 20 hours to prepare a silicone- containing fluorocopolymer. The resulting copolymer was used to form a cured coating film, and the properties of the coating film were evaluated as follows. The results obtained are shown in Tables 1 to 3 below.

Reactive silicone I: CH2=C(CH3)COOC3H6-Si(CH3)2-O-[Si(CH3)2-O]64-Si(CH3)2-C4H9 Table 1 XPS analysis at the surface of coating films NA (Si (90°) NA (F (909) NA (C (90°) NA (O(90°) NA(Si(90°)/NA(F(90°) NA(N(90°) (atomic %) (atomic %) (atomic %) (atomic %) | (atomic %) Example 1 9.9 9.5 60.7 19.9 1.04 3. 3 Example 2 12.2 8.5 54.1 25.2 1.44 3. 2 Example 3 12.7 7.3 53.1 26.9 1.73 3. 1 Example 4 14.6 4.6 57.0 23.8 3.13 3. 2 Example 5 6.7 17.0 52.4 23.9 0.39 3. 2 Example 6 2.1 32.7 50.2 15.0 0.063 3.0 Example 7 2.6 23.2 52.3 21.9 0.11 3.3 Example 8 3.1 21.7 51. 7 23.5 0.14 3.2 Example 9 20.6 2.0 60.4 17.0 10.5 3.0 Example 10 4.7 17.9 54.5 22.9 0.26 3.6 Example 11 7.7 13.4 52.0 26.9 0.57 3. 4 Example 12 5.0 9.9 56.4 28.7 0.50 1.5 Example 13 25.8 2.3 54.0 17.9 11.4 3. 2 Example 14 2.4 8.2 60.9 28.5 0.29 3. 1 Example 15 20.4 2.6 57.8 19.2 7.92 3.1 Example 16 9.9 10.4 56.9 19.7 0.95 3.2 Example 17 10.2 13.0 57.0 19.9 0.79 3. 0 Example 18 2.4 28.9 50.5 18.2 0.082 3.3 Comparative 0.0 43.8 51.1 5.1 0.00 3.2 Example 1 Comparative 0.0 41.3 52.2 6.5 0.00 4.1 Example 2 Comparative 2.0 32.9 50.2 14.9 0.060 3.1 Example 3 Table 2 Surface properties of coating films Oil ink repellency Removability of oil ink Water repellency (initial/20 times) (initial/20 times) (°) Example 1 5/5 5/5 103 Example 2 5/5 5/5 104 Example 3 5/5 5/5 104 Example 4 5/5 5/5 104 Example 5 5/5 5/5 102 Example 6 2/2 3/3 98 Example 7 4/4 4/4 100 Example 8 5/5 5/5 102 Example 9 5/5 5/5 110 Example 10 5/5 5/5 102 Example 11 5/5 5/5 102 Example 12 5/5 5/5 102 Example 13 3/3 5/5 103 Example 14 2/2 3/3 99 Example 15 5/5 5/5 107 Example 16 5/5 5/5 103 Example 17 5/5 5/5 104 Example 18 2/2 3/3 98 Comparative 1/1 1/1 91 Example 1 Comparative 1/1 1/1 90 Example 2 Comparative 1/1 1/1 96 Example 3 Table 3 Peel strength measurement Peel strength (g/50 mm) Example 1 102 Example 2 38 Example 3 36 Example 4 27 Comparative 1400 Example 1

[Conditions for cured coating film formation] The silicone-containing fluorocopolymer prepared as above was mixed with Coronate HX (Nippon Polyurethane Industry Co. , Ltd. , Japan) to give a OH/NCO ratio of 1/1, applied onto a corona-discharged PET film using a #10 bar coater, and then heated at 80°C for 24 hours. It should be noted that Coronate HX is a trimer of OCN (CH2) 6NCO.

[Composition analysis of the coating film surface] The XPS apparatus used was a SHIMADZU/KRATOS AXIS-HS (Kratos Analytical Inc. , UK).

[Analysis conditions] X-ray source for analysis: monochromatic AlKaray (60 W) Analysis area: 2 x 4 mm Elements to be analyzed: Si, F, C, O and N [Survey scanning (qualitative analysis)] Energy range for analysis: 0 to 1100 eV Pass energy: 160 eV Step: 1.0 eV Dwell: 300 ms

Conditions for a filament of a charge-neutralizing device: a current of 2 A, a potential of-1.0 V and a bias voltage of-2.7 V Take-off angle: 90° [Multiscanning (quantitative and status analysis)] Analysis energy range for each element: 87-107 eV for Si2p, 678-698 eV for F1s, 278-298 eV for Cl., 521-541 eV for 01., and 388-408 eV for N1s Pass energy: 40 eV Step: 0.1 eV Dwell: 298 ms Conditions for a filament of a charge-neutralizing device: a current of 2 A, a potential of-1.0 V and a bias voltage of-2.7V The take-off angle was set to 90° unless otherwise specified.

The concentrations of Si, F, C and O at a take-off angle 0 were determined by means of the above apparatus system as follows. First, the number of element X [A (X (6))] present at the surface of the coating film was determined for Si, F, C and 0 on the basis of the results of multiscanning. Next, the atomic concentration of element X (atomic %) was determined by the following equation: NA (X (0)) = A (X (6))/ (A (Si (0)) +A (F (0)) +A (C ((3)) +A (O (0))) X 100 (wherein X is Si, F, C or O).

For reference, the atomic concentration of N is also shown in Tables 1 and 5. The concentration of N [NA (N (6))] was determined by the following equation:

NA (N (0)) = A (N (6))/ (A (Si (0)) +A (F (0)) +A (C (0)) +A (O (0))) X 100 (wherein A (N (6)) denotes the number of N atoms present at the surface of the coating film, which is determined from the results of multiscanning).

[XPS analysis at various take-off angles 0] XPS was performed under multiscanning conditions to determine the atomic concentrations of Si, F, C and O in the same manner as shown above, except that the take-off angle 6 was set to 75°, 60°, 45°, 35°, 30° and 20°.

[Oil ink repellency] The surface of the coating film was filled with oil inks (black and red Magic Inks@), and its initial oil ink repellency was evaluated. This coating film was further allowed to stand at room temperature for 1 hour and then rubbed with a dry cloth to remove the ink. After this procedure was repeated for 20 times, the oil ink repellency of the surface of the coating film was evaluated on a scale of 1 to 5: 5 (good resistance) to 1 (no resistance).

[Repeated removal of oil ink] The surface of the coating film was filled with oil inks (black and red Magic Inks@), allowed to stand at room temperature for 1 hour, rubbed with a dry cloth to remove the inks, and then tested for initial removability of the ink. After this procedure was repeated for 20 times, the removability of the ink on the surface of the coating film was evaluated on a scale of 1 to 5: 5 (complete removal) to 1 (no removal).

[Water-repellency]

Water-repellency was evaluated as contact angle with water (unit: degree (°)).

A contact angle meter CA-DT (Kyowa Interface Science Co.

Ltd. , Japan) was used for measurement.

[Peel strength] A #31B adhesive tape (50 mm in width, Nitto Denko Co., Ltd. , Japan) was applied to the surface of the coating film using a 2 kg roller and then kept under a load of 20 g/cm2 at 70°C for 20 hours. The coating film was then allowed to stand at 23°C for 30 minutes, and was tested for its peel strength at a peel angle of 180° and at a peel rate of 300 mm/minute.

[Examples 2 to 4] The same procedure as shown in Example 1 was repeated to give copolymers, except that the amount of the reactive silicone I used in Example 1 was changed to 0. 1% by mole, 0. 2% by mole and 0.4% by mole. These copolymers were used to form coating films, and the properties of the coating film were then tested in the same manner as shown in Example 1. The results obtained are shown in Tables 1 to 3 above. It should be noted that the amount of butyl vinyl ether was reduced to balance the increase in the amount of silicone I.

Table 4 shows the data of the coating films prepared in Examples 1 to 4 and Comparative Example 1 (shown below), including the average Si concentration of each coating film determined from the weight of components (excluding a solvent) in each fluorocopolymer composition, the measured Si concentration at the surface of each coating film (measured by XPS), and the measured F concentration at the surface of each

coating film (measured by XPS). The measured Si concentration at the surface is higher than the average Si concentration in a bulk, indicating that Si moieties are localized near the surface.

Table 4 Average Si concentration of coating films and Si and F concentrations at their surface Reactive silicone Average Si concentration Si concentration at the F concentration at the (% by mole) of coating film surface of coating film surface of coating film (atomic %) (NA (Si (90°) (atomic %)) (NA (F (90°) (atomic %)) 0.00 0.0 0 42.4 0.02 0.3 7.3 21.2 0.03 (Example 1) 0.4 9.9 9.5 0.10 (Example 2) 1.2 12.2 8.5 0.20 (Example 3) 2.1 12.7 7.3 0.40 (Example 4) 4.0 14.6 4.6

The coating films of Examples 1 to 4 and Comparative Example 1 (shown below) were analyzed by XPS at varying take-off angles 0. The results obtained are shown in Table 5 below.

Table 5 XPS analysis at varying take-off angles Tale-off NA(Si(#)) NA(F(#) NA(C(#) NA(O(#) NA(N(#)) angle (atomic %) (atomic %) (atomic %) (atomic %) (atomic %) # (°) Example 1 20 18.7 0.9 51.9 28.5 1.4 30 15.3 1.0 53.0 30.7 1.5 35 13.9 3. 3 53. 0 29.8 1. 7 45 13.4 4.7 56.4 25.5 2. 1 60 11.8 7.6 57.1 23.5 2. 7 75 10.7 8.3 58.9 22.3 3.0 90 9.9 9.5 60.7 19.9 3.3 Example 2 20 22.0 0. 9 48. 1 29. 0 1. 3 30 18.0 1.2 49.0 31.8 1.6 35 18.0 1.7 48. 5 31.8 1.6 45 16.2 5.3 50.4 28.1 1.8 60 14.5 6. 4 52.5 26.6 2.6 75 13.2 7.8 53.5 25. 5 2.9 90 12.2 8.5 54.3 25.2 3. 2 Example 3 20 26.7 0.7 46.2 26.4 1. 2 30 25.5 1.1 46.6 26.8 1. 4 35 25.1 1.2 47.0 26.7 1. 6 45 22.7 2.9 47.0 27. 4 1. 9 60 15.8 5.3 50.1 28.8 2. 2 75 14.2 6.3 52.5 27.0 2. 8 90 12.7 7.3 53.1 26.9 3.1 Example 4 20 29.6 0.7 50.4 19.3 1.1 30 28.1 0.9 50.8 20.2 1.3 35 27.9 1.0 52.7 18.4 1.6 45 25.4 2.2 53.6 18.8 1.8 60 21.9 3.3 55.4 19.4 2.1 75 18.3 3.7 55.5 22.5 2.6 90 14.6 4.6 57.0 23.8 3.2 Comparative 20 0. 0 44.9 48.5 6.6 1.5 Example 1 30 0.0 43.9 49.3 6.8 1.9 35 0.0 44.8 49.2 6.0 2.2 45 0.0 46.2 50.3 3.5 2.4 60 0.0 44.0 50.5 5.5 2.6 75 0.0 44.3 50.9 4. 8 3. 1 90 0.0 43.8 51.1 5.1 3.2

Table 5 indicates that Si atoms are localized at the surface of the coating film of the present invention, whereas the concentration of F atoms increases with receding from the surface.

[Example 5] The same procedure as shown in Example 1 was repeated to give a copolymer, except that the reactive silicone I used in Example 1 was replaced with a reactive silicone II (Mw = ca.

2100,0. 03% by mole). The resulting copolymer was used to form a coating film, and the properties of the coating film were tested in the same manner as shown in Example 1. The results obtained are shown in Tables 1 and 2 above.

Reactive silicone II:

CH2=C (CH3) COOC3H6-Si (CH3) 2-O- [Si (CH3) 2-0] 25-Si (CH3) 3 [Examples 6 to 8] The same procedure as shown in Example 5 was repeated to give copolymers, except that the amount of the reactive silicone II used in Example 5 was changed to 0.001% by mole, 0. 002% by mole and 0.01% by mole. These copolymers were used to form coating films, which were then analyzed for their properties in the same manner as shown in Example 5. The results obtained are shown in Tables 1 and 2 above.

[Example 9] The same procedure as shown in Example 3 was repeated to give a copolymer, except that the reactive silicone I used in Example 3 was replaced with a reactive silicone III (Mw = ca. 10700,0. 2% by mole). The resulting copolymer was used to form a coating film, and the properties of the coating film were tested in the same manner as shown in Example 3. The results obtained are shown in Tables 1 and 2 above.

Reactive silicone III: CH2=C(CH3)COOC3H6-Si(CH3)2-O-[Si(CH3)2-O]140-Si(CH3)2-C4H9 [Example 10] The silicone-containing fluorocopolymer prepared in Example 1 was mixed with Dianal LR-199 (Mitsubishi Rayon Co., Ltd. , Japan) at a ratio of 5/5 in terms of solid content to prepare a silicone-containing fluorocopolymer composition, and the properties of the coating film were tested. The results obtained are shown in Tables 1 and 2 above.

[Example 11] A 1L autoclave equipped with a stainless-steel stirrer

(resistant up to 10 MPa) was charged with vinylidene fluoride/ tetrafluoroethylene/hydroxybutyl vinyl ether/butyl vinyl ether/a reactive silicone I (Mw = ca. 5000) at a molar ratio of 30/40/15/14.97/0. 03 as well as butyl acetate as a polymerization solvent and t-butyl peroxypivalate as a polymerization initiator. After the internal temperature was elevated to 60°C with stirring, the reaction was continued with stirring and stopped after 20 hours to prepare a hydroxy- containing copolymer. The hydroxy-containing copolymer was then mixed with 2-isocyanato ethyl methacrylate to give a NCO/OH ratio of 1/1 and then reacted to prepare a silicone-containing fluorocopolymer having an unsaturated double bond (s). This copolymer was used to form a cured coating film under the following conditions, and the properties of the resulting coating film were tested in the same manner as shown in Example 1. The results obtained are shown in Tables 1 and 2 above.

[Conditions for cured coating film formation] A 50% butyl acetate solution of the above copolymer was <BR> <BR> <BR> <BR> <BR> applied onto a corona-discharged PET film using a &num 10 bar coater, dried at 80°C for 1 minute, and then irradiated under 200 ppm oxygen using an electron beam irradiator EC250/15/180L (Iwasaki Electric Co. , Ltd. , Japan) with an acceleration voltage of 200 kV and a dose of 30 kGy.

[Example 12] The above 50% butyl acetate solution of the silicone-containing fluorocopolymer having an unsaturated double bond (s) prepared in Example 11 (100 g) was mixed with Ebecryl 80 (30 g, polyester acrylate, Daicel-UCB Co. , Ltd.),

1,6-hexanediol diacrylate (20 g) and 2-methyl-l- [4- (methyl- thio) phenyl]-2-morpholinopropanon-1-one (5 g, Ciba-Geigy) to prepare a silicone-containing fluorocopolymer composition.

This composition was used to form a cured coating film under the following conditions, and the properties of the resulting coating film were tested in the same manner as shown in Example 1. The results obtained are shown in Tables 1 and 2 above.

[Conditions for cured coating film formation] A butyl acetate solution of the above copolymer composition was applied onto a corona-discharged PET film using a #10 bar coater, dried at 80°C for 1 minute, and then irradiated in the air with ultraviolet light of 250 mJ/cm2.

[Example 13] A 1L autoclave equipped with a stainless-steel stirrer (resistant up to 10 MPa) was charged with tetrafluoroethylene /hydroxybutyl vinyl ether/butyl vinyl ether/a reactive silicone II (Mw = ca. 2100) at a molar ratio of 15/20/59/6 as well as butyl acetate as a solvent and t-butyl peroxypivalate as a polymerization initiator, to prepare a silicone-containing fluorocopolymer in the same manner as shown in Example 1. This copolymer was used to form a coating film in the same manner as shown in Example 1, and the properties of the resulting coating film were tested. The results obtained are shown in Tables 1 and 2 above.

[Example 14] The same procedure as shown in Example 13 was repeated to analyze coating film properties, except that the reactive silicone II was replaced with a reactive silicone IV (Mw = ca.

420). The results obtained are shown in Tables 1 and 2 above.

Reactive silicone IV: CH2=C (CH3) COOC3H6-Si [OSi (CH3)] 3 [Example 15] The same procedure as shown in Example 1 was repeated to analyze coating film properties, except that the reactive silicone I was replaced with a reactive silicone V (Mw = ca.

11400). The results obtained are shown in Tables 1 and 2 above.

Reactive silicone V: CH2=C (CH3) COOC3H6-Si (CH3) 2-O- [Si (CH3) 2-0] l5o-Si (CH3) 2-C4H9 [Example 16] The same procedure as shown in Example 1 was repeated to analyze coating film properties, except that the reactive silicone I was replaced with a reactive silicone VI (Mw = ca.

4750). The results obtained are shown in Tables 1 and 2 above.

Reactive silicone VI: CH2=C (CH3) COOC3H6-Si (CH3) 2-O- [Si (CH3) 2-O]60-Si(CH3)2-C4H9 [Example 17] The same procedure as shown in Example 1 was repeated to analyze coating film properties, except that the reactive silicone I was replaced with a reactive silicone VII (Mw = ca.

4600). The results obtained are shown in Tables 1 and 2 above.

Reactive silicone VII: CH2=CH-Si (CH3) 2-O- [Si (CH3) 2-o] 6o-Si (CH3) 2-CH=CH2 [Example 18] The same procedure as shown in Example 8 was repeated to analyze coating film properties, except that the reactive silicone II was replaced with the reactive silicone IV. The

results obtained are shown in Tables 1 and 2 above.

[Comparative Example 1] The same procedure as shown in Example 1 was repeated to give a copolymer, except that the reactive silicone I was excluded from the composition charged in Example 1. The molar ratio of vinylidene fluoride/ tetrafluoroethylene/hydroxybutyl vinyl ether/butyl vinyl ether/a reactive silicone I was 30. 009/40.012/15. 0045/14.9745.

The resulting copolymer was used to form a coating film in the same manner as shown in Example 1, and the properties of the resulting coating film were tested. The results obtained are shown in Tables 1 to 3 above.

[Comparative Example 2] The same procedure as shown in Example 11 was repeated to give a copolymer, except that the reactive silicone I was excluded from the composition charged in Example 11. The resulting copolymer was used to form a coating film in the same manner as shown in Example 11, and the properties of the resulting coating film were tested. The results obtained are shown in Tables 1 and 2 above.

[Comparative Example 3] The same procedure as shown in Example 5 was repeated to give a copolymer, except that the amount of the reactive silicone II was changed to 0.0008% by mole. The resulting copolymer was used to form a coating film in the same manner as shown in Example 5, and the resulting coating film was analyzed for its properties. The results obtained are shown in Tables 1 and 2 above.

The coating film of Comparative Example 3 was also analyzed by XPS at various take-off angles. The results obtained are shown in Table 6 below. In Table 6, the concentrations of Si and F were determined by the following equations: Si concentration = A (Si (#))/(A (Si (O)) +A (F (0)) +A (C (0)) +A (0 (0)) +A (N (6))) x 100 F concentration = A (F (#))/(A(Si(#)) +A (F (6)) +A (C (0)) +A (O (0)) +A (N (#))) x 100 (wherein NA (X (#)) denotes the amount of element X, as measured by XPS at a take-off angle 0).

Table 6 XPS analysis at varying take-off angles F Take-off Si concentr - concentra tien # (° ) (atomic (atomic %) Compara 20 3.9 3.0 tive Example 30 3.4 6.2 3 35 3.1 9.9 45 2.9 14.1 60 2.6 19.3 75 2.2 25.7 31. 9 31. 9

INDUSTRIAL APPLICABILITY The present invention relates to coating films having excellent stain resistance, water-and oil-repellency, chemical resistance and weather resistance. The coating films of the present invention are characterized by the in-depth distributions of Si and F, in which Si-containing moieties are localized at the surface, i. e. , the concentration of Si-

containing moieties in a silicone-containing fluorocopolymer increases with approaching to the surface of the coating films.

Thus, coating films having excellent properties can be obtained by using only a small amount of a reactive silicone. When combined with other resins and/or monomers, the silicone- containing fluorocopolymer of the present invention also <BR> <BR> results in Si-containing moieties that are highly localized near the surface. This means that coating films having excellent properties can be obtained when the copolymer is incorporated even in a small amount.

Because of their advantageous properties (e. g. , stain resistance, water-and oil-repellency, chemical resistance, weather resistance), cured coating films prepared from the silicone-containing fluorocopolymer and its composition according to the present invention are preferred for interior use (e. g. , wall, floor, furniture) where stain resistance is required; for mold release films ; for optical materials (e. g., antireflective films of display devices and the like); for outdoor use (e. g. , outer wall, film) where weather resistance is required; and for graffiti-proof applications. They are also useful for interior and exterior use for large buildings, train carriages, ships, and so on.