JP2024047871A - Liquid repellent additive - Google Patents

Abstract

To provide a liquid repellent additive capable of imparting good liquid repellency to an ultraviolet curable composition containing inorganic particles.SOLUTION: There is provided a liquid repellent additive containing an ester-based reaction product of a hydroxyl group-containing fluorinated polymer (A) and at least one (meth)acrylate-based monomer (B) selected from the group consisting of a carboxylic acid halide having a (meth)acrylate group, a carboxylic acid anhydride having a (meth)acrylate group and a carboxylic acid having a (meth)acrylate group, wherein the reaction ratio between the hydroxyl groups in the hydroxyl group-containing fluorinated polymer (A) and the (meth)acrylate-based monomer (B) is 1:1.0 to 1:1.5 by a molar ratio and the hydroxyl group-containing fluorinated polymer (A) is obtained by copolymerization of the following (a) to (C): (a) at least one (meth)acrylate monomer containing a perfluoroether moiety, (b) at least one hydroxyl group-containing (meth)acrylate-based monomer and (c) at least one (meth)acrylate-based monomer.SELECTED DRAWING: None

Description

The present invention relates to a liquid repellent additive.

A known technique for imparting liquid repellency to an ultraviolet-cured coating film is to add a liquid repellent additive made of a fluorine-containing oligomer to the ultraviolet-cured paint (Patent Documents 1 and 2). The fluorine-containing oligomers described in Patent Documents 1 and 2 have UV-reactive groups in their structure, and thus are chemically bonded to the ultraviolet-cured coating film, resulting in excellent durability of the coating film's liquid repellency. Patent Documents 1 and 2 use a urethane reaction with an isocyanate having a UV-reactive group as a method for introducing a UV-reactive group into the structure of the fluorine-containing oligomer.

On the other hand, a technique is known in which inorganic particles such as colloidal silica or hollow silica are blended into UV-curable paint in order to impart scratch resistance and lower the refractive index of the UV-curable coating film (Patent Document 3).

However, when a liquid-repellent additive made of a fluorine-containing oligomer having a urethane structure as described in Patent Documents 1 and 2 is used for an ultraviolet-curing paint containing inorganic particles, the urethane structure in the fluorine-containing oligomer structure interacts with the inorganic particles, causing the inorganic particles to aggregate, making it difficult to apply the liquid-repellent additive to an ultraviolet-curing paint containing inorganic particles.

Patent No. 5997998 JP 2020-032658 A Japanese Patent Application Laid-Open No. 61-181809

The present invention aims to provide a liquid-repellent additive that can impart good liquid repellency not only to UV-curable compositions that do not contain inorganic particles, but also to UV-curable compositions that contain inorganic particles.

In order to solve the above problems, the present inventors conducted extensive research and discovered that the use of a fluorine-containing oligomer having an ester structure can suppress the aggregation of inorganic particles.

The present invention has been completed based on these findings, and includes the following broad aspects.
[Item 1]
A liquid repellent additive comprising an ester-based reaction product of a hydroxyl group-containing fluorine-based polymer (A) and at least one (meth)acrylate-based monomer (B) selected from the group consisting of a carboxylic acid halide having a (meth)acrylate group, a carboxylic acid anhydride having a (meth)acrylate group, and a carboxylic acid having a (meth)acrylate group,
a reaction ratio of the hydroxyl groups in the hydroxyl group-containing fluorine-based polymer (A) to the (meth)acrylate monomer (B) is 1:1.0 to 1:1.5 in terms of molar ratio;
The hydroxyl group-containing fluorine-based polymer (A) is selected from the following (a) to (c):
A liquid repellent additive obtained by copolymerizing the following monomers: (a) at least one (meth)acrylate monomer containing a perfluoroether moiety; (b) at least one (meth)acrylate monomer containing a hydroxyl group; and (c) at least one (meth)acrylate monomer.
[Item 2]
Item 2. The liquid repellent additive according to item 1, wherein the monomer (a) comprises a (meth)acrylate monomer having one perfluoroether moiety and a (meth)acrylate monomer having a plurality of perfluoroether moieties.
[Item 3]
Item 3. The liquid repellent additive according to item 2, wherein the (meth)acrylate monomer containing one perfluoroether moiety is represented by the following formula (a1), and the (meth)acrylate monomer containing a plurality of perfluoroether moieties is represented by the following formula (a2):

(In the formula, R ¹ represents a hydrogen atom or a methyl group.
^R2 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms (the saturated aliphatic hydrocarbon group may be linear or branched and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-) or an amide bond (-CONH- or -NHCO-)).
^R3 represents a hydrogen atom or a methyl group.
^R4 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms (the saturated aliphatic hydrocarbon group may be linear or branched and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-) or an amide bond (-CONH- or -NHCO-)).
and n is an integer from 1 to 10.
[Item 4]
Item 4. The liquid repellent additive according to any one of Items 1 to 3, wherein the fluorine content of the hydroxyl group-containing fluorine-based polymer (A) is 20 to 35 mass %.
[Item 5]
Item 5. The liquid repellent additive according to any one of Items 1 to 4, wherein the (meth)acrylate monomer (B) is a carboxylic acid halide having a (meth)acrylate group.
[Item 6]
Item 6. The liquid repellent additive according to any one of items 1 to 5, which is dissolved in a solvent.
[Item 7]
Item 7. The liquid repellent additive according to any one of items 1 to 6, which is added to a UV curable resin.
[Item 8]
Item 8. A liquid-repellent composition comprising a UV curable resin and the liquid-repellent additive according to any one of Items 1 to 7.
[Item 9]
Item 9. A liquid-repellent cured resin obtained by irradiating the liquid-repellent composition according to item 8 with ultraviolet light.
[Item 10]
Item 10. An article comprising the liquid-repellent cured resin according to item 9.

The present invention provides a liquid-repellent additive that can impart good liquid repellency to UV-curable paints that contain inorganic particles.

The liquid repellent additive of the present invention is
A hydroxyl group-containing fluorine-based polymer (A),
(B) at least one (meth)acrylate monomer selected from the group consisting of a carboxylic acid halide having a (meth)acrylate group, a carboxylic acid anhydride having a (meth)acrylate group, and a carboxylic acid having a (meth)acrylate group;
Includes ester reaction products with

<Hydroxyl Group-Containing Fluorine-Based Polymer (A)>
The hydroxyl group-containing fluorine-based polymer (A) is a polymer obtained by copolymerizing the following monomers (a) to (c).
(a) at least one (meth)acrylate monomer containing a perfluoroether moiety; (b) at least one (meth)acrylate monomer containing a hydroxyl group; and (c) at least one (meth)acrylate monomer.

(a) At least one (meth)acrylate monomer containing a perfluoroether moiety
The perfluoroether moiety in the monomer (a) is
—O-(perfluoroalkyl group),
—O—(perfluoroalkylene group),
(perfluoroalkylene group)-O-(perfluoroalkyl group),
etc.

Specific _examples of _the perfluoroalkyl _{group include} linear or branched C1 to _C8 , preferably _{C1 to C4} , perfluoroalkyl groups such as _-CF3 , _{-CF2CF3 , -CF2CF2CF3} , -CF( _CF3 ) ₂ , _{and -CF2CF2CF2CF3} .

Specific examples of the perfluoroalkylene group include linear or _branched divalent C2 to _C8 , preferably _C2 to _C4 perfluoroalkylene groups such as _-CF2- , _-CF2CF2- , _-CF ( _CF3 )-, _{-CF2CF2CF2- , -CF2CF ( CF3} ) _- , _-CF ( _{CF3 ) CF2-} , and _{-CF2CF2CF2CF3-} .

Monomer (a) is preferably a monomer represented by the following formula (a1) or (a2):

(In the formula, R ¹ represents a hydrogen atom or a methyl group.
^R2 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms (the saturated aliphatic hydrocarbon group may be linear or branched and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-) or an amide bond (-CONH- or -NHCO-)).
^R3 represents a hydrogen atom or a methyl group.
^R4 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms (the saturated aliphatic hydrocarbon group may be linear or branched and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-) or an amide bond (-CONH- or -NHCO-)).
n is an integer from 1 to 10.

^R1 represents a hydrogen atom or a methyl group, preferably a methyl group.

^R2 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms. The saturated aliphatic hydrocarbon group may be linear or branched, and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-), or an amide bond (-CONH- or -NHCO-).

Examples of divalent saturated aliphatic hydrocarbon groups _having 1 to 10 carbon atoms include divalent saturated aliphatic hydrocarbon groups having 1 to 10 carbon atoms, such as _-CH2- , _{-CH2CH2- , -CH} (CH3)-, _{-CH2CH2CH2- ,} -CH2CH _{( CH3} )-, -CH( _{CH3 ) CH2-} , _{and -CH2CH2CH2CH3- ,} which are preferably _divalent saturated aliphatic hydrocarbon groups having ₁ to ₁₀ carbon _{atoms, and more preferably 1 to 4 carbon atoms .}

Examples of the divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms and an ether bond include -CH ₂ -O-CH ₂ CH ₂ -, -CH ₂ CH ₂ -O-CH ₂ -, -(CH ₂ CH ₂ -O) _l - (l is an integer of 1 to 5), and the like.

Examples of divalent saturated aliphatic hydrocarbon groups having ₁ to 10 carbon atoms and an ester bond include _{-CH2CH2 -COO-} , -CH2CH2 _{- OCO-} , -CH2CH2CH2- _COO- , -CH2CH2CH2- _OCO- , _{-CH2CH2 -} COO _- CH2-, -CH2CH2 _- OCO- _, -CH2CH2-COO _{- CH2-} , _-CH2CH2 -OCO- _CH2- , and the like.

Examples of the divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms and an amide bond include _{-CH2CH2 -} NHCO-, -CH2CH2 _- CONH-, _{-CH2- NHCO} -CH2-, and -CH2 _- CONH _{- CH2-} .

^R3 represents a hydrogen atom or a methyl group, preferably a methyl group.

^R4 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms. The saturated aliphatic hydrocarbon group may be linear or branched, and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-), or an amide bond (-CONH- or -NHCO-).

Examples of divalent saturated aliphatic hydrocarbon groups _having 1 to 10 carbon atoms include divalent saturated aliphatic hydrocarbon groups having 1 to 10 carbon atoms, such as _-CH2- , _{-CH2CH2- , -CH} (CH3)-, _{-CH2CH2CH2- ,} -CH2CH _{( CH3} )-, -CH( _{CH3 ) CH2-} , _{and -CH2CH2CH2CH3- ,} which are preferably _divalent saturated aliphatic hydrocarbon groups having ₁ to ₁₀ carbon _{atoms, and more preferably 1 to 4 carbon atoms .}

Examples of the divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms and an ether bond include -CH ₂ -O-CH ₂ CH ₂ -, -CH ₂ CH ₂ -O-CH ₂ -, -(CH ₂ CH ₂ -O) _l - (l is an integer of 1 to 5), and the like.

Examples of divalent saturated aliphatic hydrocarbon groups having ₁ to 10 carbon atoms and an ester bond include _{-CH2CH2 -COO-} , -CH2CH2 _{- OCO-} , -CH2CH2CH2- _{COO- ,} -CH2CH2CH2-OCO-, _{-CH2CH2 -} COO _- CH2-, -CH2CH2 _- OCO- _, -CH2CH2-COO _{- CH2-} , _-CH2CH2 -OCO- _CH2- , and the like.

Examples of the divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms and an amide bond include _{-CH2CH2 -} NHCO-, -CH2CH2 _- CONH-, _{-CH2- NHCO} -CH2-, and -CH2 _- CONH _{- CH2-} .

n is an integer from 1 to 10, preferably from 2 to 10, more preferably from 3 to 9, even more preferably from 4 to 8, and particularly preferably from 5 to 7.

Monomer (a) is commercially available or can be produced by known methods. Examples of commercially available products include AC-500, AC-600, and AC-1000 (all manufactured by Sinochem).

Monomer (a) may be used alone or in combination of two or more types.

((b) At least one hydroxyl group-containing (meth)acrylate monomer)
The monomer (b) has one or two hydroxyl groups, preferably one.
The monomer (b) is preferably a monomer represented by the following formula (b1):

(In the formula, ^R5 represents H or a methyl group.
^R6 represents a linear or branched alkylene group.
m represents an integer of 1 to 20.

^R5 represents H or a methyl group, and is preferably a methyl group.

^R6 represents a linear or branched alkylene group, preferably a linear or branched alkylene group having 1 to 6 carbon atoms, and more preferably a linear or branched alkylene group having 1 to 4 carbon atoms.

Examples of straight chain or branched alkylene groups include C 1 to C 4 alkylene groups such as -CH ₂ -, -CH ₂ CH ₂ -, -CH(CH ₃ )-, -CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )-, -CH(CH ₃ )CH ₂ -, _and -CH ₂ CH ₂ CH _{2 CH 3} -.

m is an integer from 1 to 20, preferably from 1 to 10, and more preferably from 1 to 4.

Monomer (b) is available as a commercially available product, or can be produced by a known method. Examples of commercially available products include Blenmer E, Blenmer PE-90, Blenmer PE-200, Blenmer PE-350, Blenmer P, Blenmer PP-1000, Blenmer PP-500, and Blenmer PP-800 (all manufactured by NOF Corp.), Light Ester HO-250 (N), Light Ester HOP (N), Light Ester HOA (N), Light Ester HOP-A (N), and Light Ester HOB (N) (all manufactured by Kyoeisha Chemical Co., Ltd.).

Monomer (b) may be used alone or in combination of two or more types.

(c) At least one (meth)acrylate monomer
Examples of the (meth)acrylate monomer include methyl acrylate (MA), ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, s-butyl acrylate, t-butyl acrylate, pentyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, methyl methacrylate (MMA), ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, pentyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, and benzyl methacrylate. These may be used alone or in combination of two or more.

(Method for producing hydroxyl group-containing fluoropolymer (A))
The hydroxyl group-containing fluorine-based polymer can be obtained by copolymerizing the above-mentioned monomers (a), (b) and (c). The copolymerization reaction proceeds advantageously by reacting in the presence of a radical initiator at 70 to 90° C. for 4 to 12 hours.

As for the radical initiator, it is preferable to carry out the polymerization in the presence of a radical polymerization initiator. Examples of radical polymerization initiators that can be used in the production method of the present invention include t-butyl hydroperoxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxyisobutyrate, t-butyl-α-cumyl peroxide, di-α-cumyl peroxide, α,α'-bis(t-butylperoxy)-p-diisopropylbenzene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-hexyne-3 acetyl peroxide, succinic acid peroxide, diisobutyryl peroxide, lauroyl peroxide, benzoyl peroxide, t-butyl peroxyacetate, t-butyl peroxyisobutyrate, di-isobutyl Examples of the azo compounds include peroxydicarbonate, t-butylperoxyisopropyl carbonate, methyl ethyl ketone peroxide, cyclohexanone peroxide, 2,2'-azobisisobutyronitrile, dimethyl 2,2'-azobisisobutyrate, dimethyl azobisisobutyrate (V-601, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(isobutylamidine) dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] and its disulfate, and 2,2'-azobis(2-methylamidoxime) dihydrochloride; potassium persulfate, sodium persulfate, ammonium persulfate, potassium persulfate, t-butyl hydroperoxide, benzoyl peroxide, and cumene hydroperoxide. These radical polymerization initiators may be used alone or in combination of two or more. The molecular weight of the copolymerization reaction may be adjusted using a chain transfer agent such as lauryl mercaptan, octyl mercaptan, dodecyl mercaptan, 2-mercaptoethanol, octyl thioglycolate, 3-mercaptopropionic acid, or thioglycerin.

The proportions of the monomers (a), (b) and (c) used to obtain the hydroxyl group-containing fluoropolymer are, with the total of these being 100 mass %,
Monomer (a): preferably 40 to 70% by mass, more preferably 50 to 60% by mass,
Monomer (b): preferably 10 to 40% by mass, more preferably 20 to 30% by mass,
Monomer (c): preferably 10 to 40% by mass, more preferably 20 to 30% by mass,
It is.

In the monomer (a) used to obtain the hydroxyl group-containing fluoropolymer (A), the preferred mass ratio of the monomer represented by formula (a1) to the monomer represented by formula (a2) is monomer (a1):monomer (a2) = 1:0 to 1:0.4. If the amount of monomer (a2) relative to monomer (a1) is 0.4 or less, the liquid is less likely to become turbid and the appearance is less likely to be poor, which is preferable.

The fluorine content of the hydroxyl group-containing fluoropolymer (A) is preferably 15 to 40% by mass, more preferably 20 to 35% by mass, and even more preferably 22 to 32% by mass. A fluorine content of 15% by mass or more is preferable because it provides good liquid repellency. A fluorine content of 40% by mass or less is preferable because it is less likely to cause repelling on the surface of the cured resin obtained by mixing with a UV curable resin and curing it.

The weight average molecular weight of the hydroxyl group-containing fluoropolymer (A) is preferably 3,000 to 100,000, more preferably 20,000 to 40,000. The weight average molecular weight can be calculated as a value converted into the molecular weight of standard polystyrene by gel permeation chromatography (GPC).

<(Meth)acrylate Monomer (B)>
The (meth)acrylate monomer (B) is at least one (meth)acrylate monomer selected from the group consisting of a carboxylic acid halide having a (meth)acrylate group, a carboxylic acid anhydride having a (meth)acrylate group, and a carboxylic acid having a (meth)acrylate group.

Examples of the halogen of the carboxylic acid halide having a (meth)acrylate group include fluoride, chloride, bromide, and iodide. Examples of the carboxylic acid halide having a (meth)acrylate group include acryloyl chloride, methacryloyl chloride, acryloyl bromide, methacryloyl bromide, acryloyl iodide, methacryloyl iodide, acryloyl fluoride, and methacryloyl fluoride.

Examples of carboxylic acid anhydrides having a (meth)acrylate group include acrylic anhydride and methacrylic anhydride.

Examples of carboxylic acids having a (meth)acrylate group include acrylic acid and methacrylic acid.

Among these, from the viewpoint of ease of purification after the esterification reaction of the hydroxyl group-containing fluorine-based polymer (A) and the (meth)acrylate-based monomer (B), it is preferable to use a carboxylic acid halide having a (meth)acrylate group as the (meth)acrylate-based monomer (B).

The (meth)acrylate monomer (B) may be used alone or in combination of two or more types.

<Ester reaction products>
The ester reaction product can be obtained by reacting a hydroxyl group-containing fluorine-based polymer (A) with a (meth)acrylate-based monomer (B) such that the reaction ratio between the hydroxyl group in the hydroxyl group-containing fluorine-based polymer (A) and the (meth)acrylate-based monomer (B) is 1:1.0 to 1:1.5, preferably 1:1.0 to 1:1.2, in terms of molar ratio. If necessary, the reaction is carried out in the presence of a base. Examples of the base include organic bases such as triethylamine, tributylamine, pyridine, 4-dimethylaminopyridine, diazabicyclononene, and diazabicycloundecene; inorganic bases such as sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and cesium carbonate; alkali metal alkoxides such as sodium methoxide, sodium ethoxide, and potassium tert-butoxide; and organic lithiums such as methyl lithium and butyl lithium. If necessary, the reaction may be carried out using a condensing agent, a catalyst, or the like.

1.0 to 1.5 equivalents, preferably 1.0 to 1.2 equivalents, of (meth)acrylate monomer (B) are used per equivalent of hydroxyl groups in hydroxyl-containing fluoropolymer (A), and the mixture is reacted at 25 to 80°C for 1 to 48 hours. It is preferable that 95% or more (more preferably 97% or more, even more preferably 98% or more, particularly preferably 99% or more, and most preferably 100%) of the hydroxyl groups in hydroxyl-containing fluoropolymer (A) are reacted with (meth)acrylate monomer (B) and esterified. Hydroxyl groups have the ability to adsorb to inorganic particles, so if 95% or more of the hydroxyl groups are esterified, aggregation of the inorganic particles is suppressed, which is preferable.

The weight average molecular weight of the ester reaction product is preferably 3,000 to 100,000, more preferably 20,000 to 40,000. The weight average molecular weight can be calculated as a value converted into the molecular weight of standard polystyrene by gel permeation chromatography (GPC).

<Liquid-repellent additive, liquid-repellent composition, liquid-repellent cured resin, and article>
The liquid repellent additive of the present invention is preferably a liquid liquid repellent additive that contains an ester-based reaction product and further contains a solvent. The solvent is not particularly limited as long as it is capable of dissolving the ester-based reaction product, and examples of the solvent include methylene chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, 1,1,1-trichloroethane, trichloroethylene, perchloroethylene, tetrachlorodifluoroethane, trichlorotrifluoroethane, methyl acetate, ethyl acetate, butyl acetate, amyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-hexafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, nitroethane, propylene glycol, propylene glycol monomethyl ether, propylene glycol Examples of suitable solvents include butyl ether acetate (PGMEA), dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol diacetate, tripropylene glycol, 3-methoxybutyl acetate (MBA), 1,3-butylene glycol diacetate, cyclohexanol acetate, dimethylformamide, dimethylsulfoxide, methyl cellosolve, cellosolve acetate, butyl cellosolve, butyl carbitol, carbitol acetate, ethyl lactate, isopropyl alcohol, methanol, ethanol, pentane, hexane, heptane, octane, cyclohexane, benzene, toluene, xylene, anisole, tetralin, cyclohexylbenzene, mesitylene, petroleum ether, tetrahydrofuran, and 1,4-dioxane.

The liquid repellent additive of the present invention may be appropriately blended with rust inhibitors, catalysts, antibacterial agents, flame retardants, defoamers, thickeners, viscosity regulators, leveling agents, UV absorbers, preservatives, antifreeze agents, wetting agents, pH adjusters, stabilizers, antifungal agents, light resistance stabilizers, weather resistance stabilizers, neutralizing agents, matting agents, drying accelerators, foaming agents, non-adhesive agents, deterioration inhibitors, etc., within the scope that does not impair the object of the present invention.

The liquid-repellent additive of the present invention can be added to a UV-curable resin to form a liquid-repellent composition. The UV-curable resin and the liquid-repellent composition are preferably liquid. By curing this liquid-repellent composition, liquid repellency can be imparted to the cured resin. The ester-based reaction product of the present invention can be added to a UV-curable resin to impart liquid repellency to the cured product, and is therefore useful as a liquid-repellent additive for UV-curable resins.

The liquid-repellent additive of the present invention can also be used for UV-cured resins containing inorganic particles. The liquid-repellent additive of the present invention does not have a urethane structure or a hydroxyl group, which are functional groups that are highly adsorbent to inorganic particles, and has low adsorption to inorganic particles. Therefore, even if the additive is added to a UV-cured resin containing inorganic particles, the aggregation of the inorganic particles is suppressed and the dispersibility of the inorganic particles in the UV-cured resin is not impaired.

As inorganic particles, for example, inorganic particles with an average temporary particle size of 5 nm or more and 100 nm or less can be used.

Preferred examples of inorganic particles include silica (colloidal silica, hollow silica, fumed silica, precipitated silica, etc.), alumina, zirconia, titania, zinc oxide, and other metal oxide particles.

The content of inorganic particles in the UV curable resin is not particularly limited, but can be, for example, 1 to 20% by mass, preferably 2 to 15% by mass.

Examples of UV-curable resins that can be used include acrylic resins, epoxy resins, and melamine resins. The UV-curable resin may be a bifunctional or higher curable resin in order to satisfy physical properties such as heat resistance, hot water resistance, and chemical resistance. UV-curable resins that are low in molecular weight and amorphous are preferred in order to obtain a low-viscosity, liquid-type liquid-repellent composition.

The liquid-repellent composition of the present invention preferably contains 20 to 40 mass% of UV-curable resin (solid content) and 0.05 to 2.0 mass% of the solid content of the liquid-repellent additive, with the total solid content being 100 mass%, and more preferably contains 25 to 35 mass% of UV-curable resin (solid content) and 0.2 to 0.7 mass% of the solid content of the liquid-repellent additive.

A liquid-repellent cured resin can be obtained by curing the liquid-repellent composition of the present invention by UV (ultraviolet) radiation. Curing can be carried out under the curing conditions for UV-curable resins. In a preferred embodiment, an article having a cured film as a cured resin can be obtained by applying the liquid liquid-repellent composition of the present invention to a substrate and curing it with UV radiation. This cured film has a liquid-repellent surface. Examples of substrates include silicon wafers, synthetic resins, glass, metals, and ceramics.

The synthetic resin may be either a thermoplastic resin or a thermosetting resin. Examples of glass include silicate glass, alkali silicate glass, soda-lime glass, potassium-lime glass, lead glass, barium glass, and borosilicate glass. Examples of metals include gold, silver, copper, iron, nickel, aluminum, and platinum. Examples of ceramics include oxides (e.g., aluminum oxide, zinc oxide, titanium oxide, silicon oxide, zirconia, and barium titanate), nitrides (e.g., silicon nitride and boron nitride), sulfides (e.g., cadmium sulfide), and carbides (e.g., silicon carbide).

The liquid-repellent composition can be applied to a substrate by, for example, roll coating, gravure coating, microgravure coating, flow coating, bar coating, spray coating, die coating, spin coating, dip coating, etc., and can be selected taking into consideration the type, shape, productivity, and controllability of film thickness of the substrate.

The present invention will be further explained below with reference to examples, but the present invention is not limited thereto.

<Materials used>
・AC-600:
Poly[oxy[trifluoro(trifluoromethyl)-1,2-ethanediyl]], α-(1,1,2,2,3,3,3-heptafluoropropyl)-ω-[1,2,2,2-tetrafluoro-1-[[2-[(2-methyl-1-oxo-2-propen-1-yl)oxy]ethoxy]carbonyl]ethoxy]-

(n=1 (average))
MMA: Methyl methacrylate PE-90:
Poly(oxy-1,2-ethanediyl), α-(2-methyl-1-oxo-2-propen-1-yl)-ω-hydroxy-

(m=2 (average))
Acryl-Cl: acryloyl chloride AOI: 2-isocyanatoethyl acrylate, Karenz AOI (manufactured by Showa Denko K.K.)
Futergent 601ADH2: Liquid repellent having a urethane structure and a hydroxyl group (manufactured by NEOS Corporation)
TMPT: Trimethylolpropane triacrylate DPHA: Dipentaerythritol hexaacrylate IPA-ST: IPA-dispersed silica (30 wt%) (manufactured by Nissan Chemical Industries, Ltd.)
MEK-ST-40: MEK-dispersed silica (40 wt%) (manufactured by Nissan Chemical Industries, Ltd.)
Irg184: Irgacure 184 (manufactured by BASF Japan Ltd.)

( ^1H -NMR Analysis)
Equipment: JNM-ECZ400S manufactured by JEOL Ltd.
Frequency: 400MHz
Deuterated solvent: deuterated methanol. Reference peak: tetramethylsilane was set at 0.00 ppm.

(GPC)
The weight average molecular weight (Mw) was determined by measuring a chromatogram by gel permeation chromatography (GPC) under the following conditions, and calculating the value converted into the molecular weight of standard polystyrene.
GPC device: HPLC Prominence manufactured by Shimadzu Corporation
Detector: Differential refractive index detector Column: TSKgel ALPHA-3000 manufactured by Tosoh Corporation
Eluent: Tetrahydrofuran Eluent flow rate: 0.6 ml/min Column temperature: 40° C.
Calibration curve: Created using data from 8 standard polystyrene samples

(FT-IR)
Apparatus: Nicolet iS50 manufactured by Thermo Fisher Scientific
Measurement method: ATR method

(Adsorption to glass)
A 1 wt % ethyl acetate solution of the reactive fluorine-containing oligomer synthesized in Synthesis Examples 1 to 5 below was prepared. A glass was immersed in the solution and then pulled up to form an additive film on the glass. Then, each glass sample was immersed in an ethyl acetate solvent, removed, and dried. Then, the water contact angle of the dried glass sample was measured. If the contact angle is 40° or less, it can be determined that the compound is little adsorbed to the glass.

(Liquid appearance)
The appearance of each coating liquid was visually observed.
Evaluation criteria: ◯: No silica aggregation was observed and the silica was uniformly dispersed.
×: Silica aggregation is observed.

(Coating appearance)
The coating of each film sample was visually inspected.
Evaluation criteria: ◯: The coating film is transparent and not cloudy.
×: The coating film is cloudy.

(Water contact angle measurement)
The contact angle of the prepared film sample was measured using DMo-702 (manufactured by Kyowa Interface Science Co., Ltd.) The contact angle is preferably 100° or more.

<Synthesis Example 1>
In a three-neck flask (500 ml) equipped with a cooling tube, 50 parts by mass of AC-600, 20 parts by mass of PE-90, 30 parts by mass of MMA, 200 parts by mass of butyl acetate, 0.22 parts by mass of lauryl mercaptan, and 0.25 parts by mass of V-601 (oil-soluble azo polymerization initiator, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were placed. Nitrogen gas was introduced into the reaction solution, and the inside of the reaction vessel was replaced with nitrogen. After the nitrogen replacement, the reaction solution was heated to 80° C. while stirring to start the reaction. Then, stirring was continued at 80° C. for 8 hours. The end of the reaction was confirmed by the disappearance of the peaks characteristic of each acrylate in ¹ H-NMR. 100 mol % of potassium carbonate and 100 mol % of acrylic acid chloride were added to the synthesized fluorine-containing oligomer PE-90, and stirring of the reaction solution was continued at 50° C. for 8 hours. The end of the reaction was confirmed using ¹ H-NMR. The reaction solution was filtered to remove inorganic compounds, thereby obtaining a reactive fluorine-containing oligomer 1. The weight average molecular weight (Mw) in terms of polystyrene measured by GPC was 30,000. In addition, a test of the adsorption of the reactive fluorine-containing oligomer 1 to glass was carried out (Table 2).

<Synthesis Example 2>
Reactive fluorine-containing oligomer 2 was synthesized by the same procedure as in Synthesis Example 1, except that the monomer weights were changed to those shown in Table 1. The weight average molecular weight (Mw) in terms of polystyrene measured by GPC was 30,000. In addition, a test of the adsorption of reactive fluorine-containing oligomer 2 to glass was carried out (Table 2).

<Synthesis Example 3>
In a three-neck flask (500 ml) equipped with a cooling tube, 50 parts by mass of AC-600, 20 parts by mass of PE-90, 30 parts by mass of MMA, 200 parts by mass of butyl acetate, 0.22 parts by mass of lauryl mercaptan, and 0.25 parts by mass of V-601 (oil-soluble azo polymerization initiator, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were placed. Nitrogen gas was introduced into the reaction solution, and the inside of the reaction vessel was replaced with nitrogen. After the nitrogen replacement, the reaction solution was heated to 80°C while stirring to start the reaction. Then, stirring was continued at 80°C for 8 hours. The end of the reaction was confirmed by the disappearance of the peaks characteristic of each acrylate in ¹ H-NMR. 50 mol% of AOI and 1 mol% of triethylamine were added to the synthesized fluorine-containing oligomer PE-90, and stirring of the reaction solution was continued at 50°C for 8 hours. The end of the reaction was confirmed by the disappearance of -N=C=O absorption using FT-IR. The target reactive fluorine-containing oligomer 3 was obtained. The weight average molecular weight (Mw) in terms of polystyrene measured by GPC was 30,000. Furthermore, a test of the adsorption of reactive fluorine-containing oligomer 3 to glass was carried out (Table 2).

<Synthesis Examples 4 and 5>
Reactive fluorine-containing oligomers 4 and 5 were synthesized by the same procedure as in Synthesis Example 1, but using monomer weights as shown in Table 1. The weight average molecular weight (Mw) in terms of polystyrene measured by GPC was 30,000. In addition, the reactive fluorine-containing oligomers 4 and 5 were subjected to a glass adsorption test (Table 2).

<Preparation of UV curable liquid>
A UV curable liquid was prepared according to the formulation shown in Table 3.

Example 1
The reactive fluorine-containing oligomer 1 synthesized in Synthesis Example 1 was added to the UV curing liquid so that the active ingredient concentration was 0.3 wt %, to prepare a coating liquid. The coating liquid was applied to a PET film using a bar coater No. 8. The coated film was dried at 100°C for 1 minute. The dried film was cured with UV to prepare a film sample. Thereafter, the liquid appearance of the coating liquid, the coating film appearance of the film sample, and the water contact angle were measured. The results are shown in Table 4.

<Examples 2 to 4, Comparative Examples 1 to 8>
A coating solution was prepared and a film sample was produced in the same manner as in Example 1, except that the composition was changed to that shown in Table 2. Then, the liquid appearance of the coating solution and the coating appearance of the film sample were evaluated, and the water contact angle was measured. The results are shown in Tables 4 and 5.

The fluorine-containing oligomers of Examples 1 to 4 have no hydroxyl groups or urethane structures, and therefore have low adsorption to silica, making it possible to suppress the aggregation of silica particles. In addition, the fluorine-containing oligomers used in Examples 1 to 4 also have low adsorption to glass.

On the other hand, in Comparative Examples 1 to 8, the silica particles aggregated because compounds having hydroxyl groups and/or urethane structures were used. In addition, the compounds also had high adsorption to glass.

Claims (10)

A liquid repellent additive comprising an ester-based reaction product of a hydroxyl group-containing fluorine-based polymer (A) and at least one (meth)acrylate-based monomer (B) selected from the group consisting of a carboxylic acid halide having a (meth)acrylate group, a carboxylic acid anhydride having a (meth)acrylate group, and a carboxylic acid having a (meth)acrylate group,
a reaction ratio of the hydroxyl groups in the hydroxyl group-containing fluorine-based polymer (A) to the (meth)acrylate monomer (B) is 1:1.0 to 1:1.5 in terms of molar ratio;
The hydroxyl group-containing fluorine-based polymer (A) is selected from the following (a) to (c):
A liquid repellent additive obtained by copolymerizing the following monomers: (a) at least one (meth)acrylate monomer containing a perfluoroether moiety; (b) at least one (meth)acrylate monomer containing a hydroxyl group; and (c) at least one (meth)acrylate monomer. The liquid repellent additive according to claim 1, wherein the monomer (a) includes a (meth)acrylate monomer containing one perfluoroether moiety and a (meth)acrylate monomer containing multiple perfluoroether moieties. The liquid repellent additive according to claim 2, wherein the (meth)acrylate monomer containing one perfluoroether moiety is represented by the following formula (a1), and the (meth)acrylate monomer containing a plurality of perfluoroether moieties is represented by the following formula (a2):
(In the formula, R ¹ represents a hydrogen atom or a methyl group.
^R2 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms (the saturated aliphatic hydrocarbon group may be linear or branched and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-) or an amide bond (-CONH- or -NHCO-)).
^R3 represents a hydrogen atom or a methyl group.
^R4 represents a divalent saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms (the saturated aliphatic hydrocarbon group may be linear or branched and may optionally have an ether bond (-O-), an ester bond (-COO- or -O-CO-) or an amide bond (-CONH- or -NHCO-)).
and n is an integer from 1 to 10. The liquid repellent additive according to claim 1, wherein the fluorine content of the hydroxyl group-containing fluoropolymer (A) is 20 to 35 mass %. The liquid repellent additive according to claim 1, wherein the (meth)acrylate monomer (B) is a carboxylic acid halide having a (meth)acrylate group. The liquid repellent additive according to claim 1, which is dissolved in a solvent. The liquid repellent additive according to claim 1, which is added to a UV curable resin. A liquid-repellent composition comprising a UV-curable resin and the liquid-repellent additive according to claim 1. A liquid-repellent cured resin obtained by irradiating the liquid-repellent composition according to claim 8 with ultraviolet light. An article comprising the liquid-repellent cured resin according to claim 9.