JPH10140047A - Additive for powder coating and powder coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject additive comprising an inorganic powdery material mixed with a liquid fluorine atom-containing organic compound and capable of imparting excellent water repellency and excellent oil repellency to powder coatings. SOLUTION: This additive comprises a powdery mixture obtained by mixing (A) 100 pts.wt. of an inorganic fine powdery material having a specific surface area of >=2m<2> /g (preferably silica, alumina, titania) with (B) 1-200 pts.wt. of a fluorine atom-containing organic compound which is liquid at 5-50 deg.C. The component A is preferably preliminarily subjected to a hydrophobic surface- forming treatment using a silane treating agent. The additive is preferably added to the powder coating composition in an amount of 0.1-50wt.%, preferably 0.5-30wt.%. The addition of the additive to the powder coating enables to form coating films excellent in water repellency and oil repellency to various kinds of substrate surfaces.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an additive for a powder coating and a powder coating composition, and more particularly to an additive for a powder coating capable of imparting excellent water repellency and oil repellency to the powder coating, and to a powder coating additive. The present invention relates to a powder coating composition which is added and blended.

[0002]

2. Description of the Related Art Powder coatings are excellent in environmental aspects because they do not use solvents, and are being developed because they can be expected to save labor. As such a powder coating, for example,
Epoxy-based powder coatings, polyester-based powder coatings, acrylic-based powder coatings, etc. have been commercialized, and these powder coatings are mixed with polydimethylsiloxane and methylphenylpolysiloxane for polyester-based powder coatings. Resin compositions (see JP-A-54-96536) and epoxy resin powder coating compositions (JP-A-1-152169).
No. Gazette Bulletin) has been proposed. However, although these compositions are excellent in coating surface smoothness, moisture resistance and thermal shock resistance, they have a drawback that water repellency and oil repellency are not sufficient.
On the other hand, as a method for forming a film having excellent water repellency and oil repellency, for example, after forming a protective layer composed of a hydrolyzed condensate of an organotrialkoxysilane on the surface of a base material, a gaseous A method of contacting a fluoroalkyl group-containing organosilane is known (see Japanese Patent Publication No. 7-45586). However, this method has a problem that the operation is complicated because the surface processing step is performed in two stages. A method of chemically adsorbing fluorocarbon group-containing trichlorosilane on the surface of a substrate has also been proposed (see JP-A-5-193056).
Since this step is performed after applying the paint, there is a problem that the operation is complicated. For this reason, there has been a long-awaited demand for a powder coating material that exhibits excellent water and oil repellency simply by coating.

[0003]

The inventors of the present invention have made intensive studies to solve the above problems, and as a result, have reached the present invention.
That is, an object of the present invention is to provide a powder coating additive which can impart excellent water repellency and oil repellency to a powder coating and a powder coating composition obtained by adding and blending the additive.

[0004]

According to the present invention, there are provided (A) 100 parts by weight of an inorganic fine powder having a specific surface area of 2 m ² / g or more and (B) 5 parts by weight of an inorganic fine powder.
Fluorine atom-containing organic compound 1 which is liquid within the range of -50 ° C
To 200 parts by weight of a powdery mixture, and an additive for a powder coating; and 0.1 to 50% by weight of the additive for a powder coating. And a powder coating composition.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the powder coating additive of the present invention will be described. (A) used in the additive of the present invention
The inorganic fine powder of the component may have a specific surface area of 2 m ² / g or more, preferably 50 m ² / g or more, more preferably 1 m ² / g or more.
It is a fine powder having a specific surface area of not less than 00 m ² / g. Examples of such inorganic fine powder include silica, alumina, titania, calcium carbonate, calcium silicate, barium sulfate, magnesia, talc, mica, clay, boron nitride, iron sand, iron oxide, zinc oxide, glass beads, glass flake, and glass. Examples include a balloon, diatomaceous earth, and metal powder. Among them, silica, alumina and titania are preferred. Examples of the silica include dry silica produced by a dry method, wet silica produced by a wet method, fused silica, and crystalline silica. Alumina and titania include those produced by the same method. It is preferable that the inorganic fine powder has been subjected to a surface hydrophobizing treatment with a silane-based treating agent in advance. The silane-based treating agent to be used may be any one which can react with the above-mentioned inorganic fine powder and hydrophobize the surface thereof, and can impart trimethylsilyl group, dimethylsilyl group or monomethylsilyl group to the surface of the above-mentioned inorganic fine powder. preferable. Examples of the silane-based treating agent capable of providing a trimethylsilyl group include trimethylchlorosilane and hexamethyldisilane, and examples of the silane-based treating agent capable of imparting a dimethylsilyl group include dimethyldichlorosilane, dimethyldimethoxysilane, and polydimethylsilazane. Examples of the silane-based treating agent capable of providing a monomethylsilyl group include methyltrichlorosilane and methyltrimethoxysilane. In addition, γ- (2-
Aminoethyl) aminopropyltrimethoxysilane, γ
Silane coupling agents having organic functional groups such as methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropylmethyldimethoxysilane can be used.

The fluorine-containing organic compound (B), which is the other component of the additive of the present invention, is a component characteristic of the present invention, and is a simple substance, an oligomer or It is a polymer. In addition, 5-50
The term “liquid within the range of ° C.” means that it is only necessary to be liquid under a certain temperature condition within this range. Examples of such a fluorine atom-containing organic compound include organosilicon compounds such as a fluorine atom-containing organosilane and a fluorine atom-containing organopolysiloxane, as well as perfluoroalkylethylene, perfluoropolyethylene, perfluoroalkane, perfluoroalkyl alcohol, and perfluoroalkyl alcohol. Fluoropolyether, perfluoroalkyl acrylate, and perfluoroalkyl methacrylate are exemplified. Among these, a fluorine atom-containing organosilane or a fluorine atom-containing organopolysiloxane is preferable, and in particular, a formula: F (CF ₂ ) _a —R ¹ — (wherein R ¹ is an alkylene group or an alkyleneoxyalkylene) bonded to a silicon atom. And a is an integer of 4 or more.) More preferred is an organosilane or organopolysiloxane having a group represented by the formula: Examples of such an organosilane include an alkoxysilane and a hydrosilane represented by the following formula. In the following formula, Me represents a methyl group, and Et represents an ethyl group. _{F (CF 2) C 2 H} 4 Si (OMe) 3 F (CF 2) C 2 H 4 SiMe (OMe) 2 F (CF 2) 4 C 2 H 4 Si (OMe) 3 F (CF 2) 4 C _{2 H 4 SiMe (OMe) 2} F (CF 2) 4 C 2 H 4 SiMe 2 (OMe) F (CF 2) 8 C 2 H 4 Si (OMe) 3 F (CF 2) 8 C 2 H 4 Si ( OEt) ₃ F (CF ₂ ) ₈ C ₂ H ₄ OC ₂ H ₄ Si (OEt) ₃ F (CF ₂ ) C ₂ H ₄ SiH ₃ F (CF ₂ ) C ₂ H ₄ SiMeH ₂ F (CF ₂ ) ₈ C ₂ H ₄ SiH ₃

The fluorine-containing organopolysiloxane is represented by the general formula: {F (CF ₂ ) _a -R ¹ -R ² _b SiO _{(3-b) / 2} } _n (R ³ _c S
_{iO (4-c) / 2} ) m - (O 1/2 X) compounds represented by _y is preferred. In the above formula, R ¹ is an alkylene group or an alkyleneoxyalkylene group. Examples of the alkylene group include ethylene, methylethylene, ethylethylene, propylethylene, butylethylene, propylene, butylene, 1-methylpropylene, pentylene, hexylene, heptylene, octylene, A nonylene group and a decylene group; Examples of the alkyleneoxyalkylene group include, for example,
Examples include an ethyleneoxyethylene group, an ethyleneoxypropylene group, an ethyleneoxybutylene group, a propyleneoxyethylene group, a propyleneoxypropylene group, a propyleneoxybutylene group, a butyleneoxyethylene group, and a butyleneoxypropylene group. R ² is the same or different alkyl group or aryl group, and examples of the alkyl group include a methyl group, an ethyl group, a propyl group,
Butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, hexadecyl and octadecyl groups. As the aryl group, for example,
Examples include a phenyl group, a tolyl group, and a xylyl group. R ³
Is a substituted or unsubstituted monovalent hydrocarbon group, and examples of the unsubstituted monovalent hydrocarbon group include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and nonyl. Alkyl groups such as phenyl, tolyl, and xylyl groups; alkenyl groups such as vinyl, allyl, and 5-hexenyl; and monovalent substitution. As the hydrocarbon group, 3-glycidoxypropyl group, 2- (3,4-epoxycyclohexylethyl)
Group, 3- (3,4-epoxycyclohexylpropyl)
An organic group containing an epoxy group such as a 3,4-epoxycyclohexyl group; an organic group containing an amino group such as a 3-aminopropyl group or 3- (2-aminoethyl) aminopropyl group; 3-hydroxypropyl group, acryloxy Examples thereof include a propyl group, a methacryloxypropyl group, a 3-mercaptopropyl group, and a 3-isocyanatopropyl group. X
Is a hydrogen atom or a monovalent hydrocarbon group having 1 to 5 carbon atoms, and examples of the monovalent hydrocarbon group having 1 to 5 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group and a pentyl group. Is done. a is an integer of 4 or more, preferably 4
Is an integer of １２12, and 4, 6, and 8 are exemplified. b is 0
And c is an integer of 0 to 3. n is a number greater than 0, m and y are numbers greater than 0, and m / y
n is preferably in the range of 0 to 200. Examples of the structure of the organopolysiloxane include a straight chain, a straight chain having a branched chain, a network, and a three-dimensional structure. At least one compound represented by the formula: F (CF ₂ ) _a -R ^1-in the molecule is used. SiO
_It preferably has a siloxane unit represented by _3/2 (wherein R ¹ and a are the same as described above).

As such an organopolysiloxane, a compound represented by the following average unit formula is exemplified. In the following formula, Me represents a methyl group, and Ph represents a phenyl group. ｛Me ₃ SiO _1/2 ｝ _0.9 (SiO _4/2 ) _1.0 ｛F (CF ₂ ) ₄
C ₂ H ₄ SiO _3/2 ｝ _0.1 ｛Me ₂ SiO _2/2 ｝ _1.8 ｛F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 ｝
_12.2 {MeSiO _3/2 } _0.7 {F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 }
_5.5 {MeSiO _3/2 } _0.7 {F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 }
_5.5 (O _1/2 H) _1.0 (SiO _4/2 ) _0.35 ｛F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 ｝ _4.34 ｛F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 ｝ ₈ ｛F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 ｝ ₁₂ (O _1/2 Me) ₁ ｛MeSiO _3/2 ｝ _0.5 ｛F (CF ₂ ) ₄ C ₂ H ₄ OC ₂ H ₄ Si
O _3/2 ｝ _2.0 ｛F (CF ₂ ) ₈ C ₂ H ₄ (CH ₃ ) SiO｝ ₁ ｛Ph ₂ SiO｝
₁₀ ｛Me ₂ SiO｝ ₁₈ ｛PhSiO _3/2 ｝ ₂ ｛F (CF ₂ ) ₈ C _{2
H 4 SiO 3/2} 1 {PhSiO} 3/2} 9 {F (CF 2) 4 C 2 H 4 SiO 3/2} 1 {Me 3 SiO 1/2} 1.2 {SiO 4/2} 1 {PhSi
O _3/2 ｝ ₉ ｛F (CF ₂ ) ₄ -C ₂ H ₄ SiO _3/2 ｝ ₁ ｛Me ₃ SiO _1/2 ｝ _1.2 ｛SiO _4/2 ｝ ₁ ｛F (CF ₂ ) ₄ C _{2
H 4 SiO 3/2} 1 {Ph} 2 SiO} 9 {F (CF 2) 4 C 2 H 4 SiO 3/2} 1 {F (CF 2) 8 C 2 H 4 (CH 3) SiO} 1 { Ph ₂ SiO｝ ₈
｛PhSiO _3/2 ｝ ₁ ｛Me ₃ SiO _1/2 ｝ _0.7 ｛SiO _4/2 ｝ ₁ ｛Ph ₂ SiO｝
₁₀ ｛F (CF ₂ ) ₈ -C ₂ H ₄ SiO _3/2 ｝ ₁ ｛Me ₃ SiO _1/2 ｝ _0.7 ｛SiO _4/2 ｝ ₁ ｛Ph ₂ SiO｝
₈ ｛F (CF ₂ ) ₈ -C ₂ H ₄ MeSiO｝ ₁ ｛PhSiO _3/2 ｝ ₁₀ ｛F (CF ₂ ) ₈ C ₂ H ₄ SiO _3/2 ｝ ₁ ｛Ph ₂ SiO _2/2 ｝ ₁₀ F (CF ₂ ) ₈ C ₂ H ₄ SiO _3/2 ｝ ₁ ｛Ph ₂ SiO｝ ₅ ｛PhSiO _3/2 ｝ ₅ ｛F (CF ₂ ) ₈ C ₂
H ₄ SiO _3/2 ｝ ₁ ｛F (CF ₂ ) ₈ C ₂ H ₄ SiO _3/2 ｝ ₃ ｛PhSiO _3/2 ｝
₇ (NH ₂ C ₃ H ₆ —SiO _3/2 ) ₃ ｛F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 ｝ ₃ ｛PhMeSi
O _2/2 ｝ ₇ (NH ₂ C ₃ H ₆ —SiO _3/2 ) ₄ (O _1/2 Me) ₃

Embedded image

Embedded image ｛F (CF ₂ ) ₄ C ₂ H ₄ SiO _3/2 ｝ ₂ ｛PhSiO _3/2 ｝
_{7 {HO (CH 2) 3} -SiO 3/2} 3

The organopolysiloxane is, for example,
General formula: F (CF ₂ ) _a -R ¹ -R ² _b SiZ _3-b (wherein, R
¹ , R ² , a and b are the same as above, and Z is a halogen atom such as chlorine or bromine or an alkoxy group such as methoxy, ethoxy, propoxy or butoxy. After hydrolyzing the fluoroorganosilane represented by the formula (1 ₎ , a condensation reaction is carried out, or the above fluoroorganosilane and the general formula: R ³ _c SiZ _{(4- c)} (wherein R ³ , Z and c
Is the same as above. ) Is co-hydrolyzed with an organic solvent in the presence of an aqueous solution and then subjected to a condensation reaction. As a method of co-hydrolysis, for example, a method of dissolving a mixture of silanes represented by the above general formula in an organic solvent, and then dropping this solution into an aqueous solution with stirring, or while stirring this organic solvent solution, There is a method in which an aqueous solution is dropped therein. The organic solvent used at this time is preferably one that dissolves the above-mentioned silane and the resulting organopolysiloxane; ethers such as diethyl ether and tetrahydrofuran; ketones such as acetone and methyl isobutyl ketone; α, α, Examples include fluorine-based solvents such as α-trifluorotoluene and hexafluoroxylene; and volatile silicone-based solvents such as hexamethyldisiloxane, hexamethylcyclotrisiloxane, and octamethylcyclotetrasiloxane. The concentration of the silane in the organic solvent is usually
It is preferable that the concentration of the resulting organopolysiloxane be in the range of 10 to 80% by weight. As the aqueous solution, an aqueous solution of an acid such as sulfuric acid, nitric acid or hydrochloric acid is used as necessary. Among these, an aqueous solution of hydrochloric acid is preferable. In this case, the concentration of hydrogen chloride needs to be 5% by weight or more. The temperature during and after dropping is 0 to 1
A range of 20 ° C. is preferred. The aqueous layer can be separated from the solution of the organopolysiloxane thus obtained by adding an organic solvent or water as necessary and allowing to stand. After separation of the aqueous layer, it is preferable to wash with water until the organic solvent layer containing the organopolysiloxane becomes neutral, and to further dehydrate. The dehydration may be carried out using a water separation tube under the azeotropic condition of an organic solvent. As the organic solvent used at this time, a solvent having low solubility in water is preferable. The organopolysiloxane thus obtained contains some residual silanol groups and alkoxy groups, and its content is usually in the range of 0.01 to 10% by weight, preferably 0.05 to 10% by weight. It is in the range of 5% by weight.

The additive of the present invention is obtained by adding 1 to 200 parts by weight of the component (B) to 100 parts by weight of the component (A). Particularly, the compounding amount of the component (B) is 5 to 150 parts by weight. It is preferably in the range of parts. If the amount is less than 1 part by weight, the effect of improving water repellency and oil repellency is insufficient.
If the amount exceeds 0 parts by weight, the powder form cannot be maintained.

The additive of the present invention can be easily produced by uniformly mixing the above components (A) and (B). This mixing can be performed using a conventional mixer such as a Henschel mixer, a super mixer, a dental mixer, a V-type blender, a double cone mixer, a Nauta mixer, or the like. At this time, it is preferable to previously charge the component (A) into the mixer, and to add the component (B) while stirring the mixture. However, the mixing order may be reversed.

Next, the powder coating composition of the present invention will be described. The powder coating composition of the present invention is characterized by containing the powder coating additive of the present invention described above. Its content is in the range of 0.1% to 50% by weight, but preferably in the range of 0.5% to 30% by weight. This is because if the amount is less than 0.1% by weight, the effect of improving water repellency and oil repellency is insufficient, and if it exceeds 50% by weight, the adhesion of the coating film to the substrate is reduced. Such a powder coating composition of the present invention contains, as a main component, ordinary powder coating components, for example, various thermosetting or thermoplastic resin vehicles and pigments for coating. Examples of thermosetting resins include epoxy resin, epoxy / novolak (low-temperature curing) resin, acrylic resin, polyester resin, and acrylic resin.
Examples include polyester resin, epoxy / polyester blend resin, polyester-modified silicone resin, acrylic-modified silicone resin, epoxy-modified silicone resin, phenolic resin, and the like. Examples of the thermoplastic resin include nylon, PVC, polypropylene, and polyethylene. Among these, from the viewpoint of durability,
Thermosetting resin vehicles are preferred.

The powder coating composition of the present invention includes 99.9% to 50% by weight of a resin vehicle for coating selected from the group consisting of (C) epoxy resin, polyester resin and acrylic resin. D) A composition comprising 0.1% to 50% by weight of the above-mentioned additive of the present invention is preferred. The epoxy resin of the component (C) may be any polyfunctional resin, for example, glycidyl ethers, glycidyl esters, glycidylamines, linear aliphatic epoxides, alicyclic epoxides, and hydantoin type epoxy resins. And the like. Polyester resins include saturated and unsaturated polyester resins. Examples of the acrylic resin include a copolymer of an unsaturated ester and an unsaturated carboxylic acid, an epoxy copolymer, and a glycidyl ester copolymer.
Copolymers such as acrylic / polyester resins and epoxy / polyester blend resins can also be used.

The powder coating composition of the present invention may contain, if necessary, conventionally used silicone-based additives, curing agents, and other leveling agents. Examples of curing agents for resin vehicles for coatings include aliphatic monocarboxylates, bisazlactones, aliphatic dicarboxylic esters, aminoplasts, aminotriazine derivatives, lithium salts / quaternary ammonium compounds, and tetrakismethoxymethylglycoluril. No. When epoxy resin is used as a resin vehicle for paint, various aromatic amines, imidazole,
Dicyandiamide, dihydrazide compounds, and acid anhydrides are exemplified. Further, a curing accelerator may be used in combination.

The addition of a silane coupling agent to the composition of the present invention to improve the adhesion to various substrates, and the addition of a curing accelerator to improve the curability of the composition according to the present invention. It does not matter as long as the purpose of is not spoiled. Examples of the silane coupling agent to be used include a compound represented by the following formula. _{H 2 NCH 2 CH 2 Si (} OC 2 H 5) 3 NH 2 CH 2 CH 2 NH (CH 2) 3 Si (OCH 3) 3

Embedded image CH ₂ ＣＨCHSi (OCH ₃ ) ₃ CH ₂ ＣＨCHSi (OC ₂ H ₅ ) ₃

Embedded image CH ₂ ＣＨCHSi (OOCCH ₃ ) ₃ HS (CH ₂ ) ₃ Si (OCH ₃ ) ₃

Embedded image These silane coupling agents can be used alone or as a mixture of two or more kinds, and the amount of addition is preferably in the range of 0.01 to 10% by weight based on the composition of the present invention.
In addition to these, additives such as various pigments, dyes, light absorbers, fluorescent paints, photosensitizers, and color formers can be added to the composition of the present invention as needed.

The composition of the present invention comprises a resin vehicle for paints,
It can be easily produced by uniformly mixing the additive of the present invention and other raw material components for powder coating.
Means for mixing the additive of the present invention with various powder coating components include, for example, a Henschel mixer, a super mixer,
Examples include a dental mixer, a V-type blender, a double cone mixer, a Nauta mixer, a kneader mixer, a twin screw extruder, and two rolls. The mixing conditions are as follows:
It may be at room temperature or under heating.

As a method for treating a substrate with the composition of the present invention, a usual method for treating a powder coating, for example, a fluid immersion method, an electrostatic bed method, an electrostatic spray method, and a cascade method. In particular, a method using a triboelectric powder electrostatic gun is simple. After uniformly applying the composition of the present invention to the substrate surface by such a method, under appropriate heating temperature conditions,
For example, a coating film can be formed by heating at a heating temperature of 100 to 250 ° C. for 30 seconds to 60 minutes.

As the substrate to which the composition of the present invention is applied,
For example, various glasses, ceramics, metals, synthetic resins, and the like can be used. It is preferable that the surface of the substrate to be used is previously washed with an organic solvent, a detergent, or the like. Examples of the coated article to which the composition of the present invention has been applied include microwave oven parts,
Household appliances such as water heaters, stoves, kitchen appliances and refrigerators; heavy electrical appliances; parts of bicycles and automobiles; metal products such as agricultural equipment; building materials such as gates and fences; road materials such as traffic signs and guardrails; Can be

The composition of the present invention as described above forms a coating film having excellent water and oil repellency and low surface tension on various substrate surfaces. Further, since this coating film has excellent antifouling properties, mold release properties, heat resistance, weather resistance, and chemical resistance, it can be used for various applications requiring these properties. Such a composition of the present invention comprises water droplets, snow, ice, oil, thermoplastic powder,
Anti-adhesion agent for resin fine powder; anti-fouling coating agent;
It is suitably used as a coating agent for peeling or releasing.

[0020]

The present invention will be described below in detail with reference to examples.
In the examples, the water repellency of the coating film was evaluated by measuring the contact angle with water, and the oil repellency was evaluated by measuring the contact angle with methylene iodide and hexadecane.
The contact angle was measured according to the following method. Water, methylene iodide and hexadecane were dropped at five places on the coating film using a microsyringe at a temperature of 20 ° C. The contact angles were measured using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.), and the average of these was defined as the contact angle of the film.

[0021]

In Synthesis Example 1] flask, water 84 g, a mixture of isopropyl alcohol 50g and 1,3-bis (trifluoromethyl) benzene 125g was charged into which stirring this formula: C ₄ F ₉ C A mixed solution of 160 g of nonafluorohexyltrichlorosilane represented by ₂ H ₄ SiCl ₃ and 84 g of 1,3-bis (trifluoromethyl) benzene was added dropwise. After completion of the dropwise addition, the mixture was mixed for 2 hours. Next, this was allowed to stand, an aqueous layer was separated, and the obtained organic solvent layer was repeatedly washed with pure water until neutral. After washing, the organic solvent is removed by heat stripping under reduced pressure, and the formula: {C ₄ F ₉ C ₂ H ₄ SiO _3/2 } _x (O _1/2 H) _y (where x and y are 124 g of a fluorine atom-containing organopolysiloxane represented by the following formula: This organopolysiloxane was a colorless liquid at 25 ° C. 60 parts of the obtained organopolysiloxane and a wet-process silica having a specific surface area of 200 m ² / g [manufactured by Nippon Silica Co., Ltd .;
100 parts of Nipsil LP] was mixed for 2 minutes using a dental mixer to obtain a powdery mixture.

[0022]

[Synthesis Example 2] 9 g of water, 49 g of methanol,
0.2 g of tetrabutyl titanate, 11.7 g of 3-glycidoxypropyltrimethoxysilane, formula: C ₄ F ₉ C ₂ H
73 g of nonafluorohexyltrimethoxysilane represented by ₄ -Si (OCH ₃ ) ₃ was added, and these were stirred at 60 ° C. for 6 hours. Then, the mixture is heated to 80 ° C. and the volatile components are removed by stripping under reduced pressure to obtain the formula: {C ₄ F ₉ C ₂ H ₄ SiO _3/2 ｝ _n } QSiO _3/2 ｝ _m (where n is The average is 8, m is an average, 2. Q is 3.
-Represents a glycidoxypropyl group. ) Was obtained in an amount of 70 g. This organopolysiloxane was a white liquid at 25 ° C.
90 parts of the obtained organopolysiloxane and a specific surface area of 150 m
100 parts of ² / g dry process silica (4% carbon content) was mixed for 2 minutes using a dental mixer to obtain a powdery mixture.

[0023]

Example 1 Thermosetting polyester resin powder coating [manufactured by Toupe Co., Ltd .; trade name, tor powder # 4000] 10
To 0 parts, 2 parts of the powdery mixture obtained in Synthesis Example 1 was added and mixed with a spatula for 2 minutes to prepare a powder coating composition. The obtained powder coating composition was applied to an iron plate by spraying. Next, this was heated at 200 ° C. for 20 minutes to form a coating film on an iron plate. The contact angle of the coating film was measured, and the results are shown in Table 1.

[0024]

Example 2 A dental mixer was prepared by mixing 60 parts of the fluorine-containing organopolysiloxane obtained in Synthesis Example 1 and 100 parts of titanium oxide having a specific surface area of 50 m ² / g [manufactured by Nippon Aerosil Co., Ltd .; trade name: titanoxide 25]. And mixed for 2 minutes to obtain a powdery mixture. This powdery mixture 2
To 100 parts of a thermosetting polyester resin-based powder coating (manufactured by Toupe Co., Ltd .; trade name, Toa Powder # 4000), and mixed with a dental mixer for 2 minutes to obtain a powder coating composition. Was prepared. The obtained powder coating composition was applied to an iron plate by spraying. Then add this to 200
C. for 20 minutes to form a coating on the iron plate. The contact angle of the coating film was measured, and the results are shown in Table 1.

[0025]

Example 3 To 100 parts of a glycidyl acrylic resin-based powder coating (manufactured by Shinto Paint Co., Ltd .; trade name Inovax A), 2 parts of the powdery mixture obtained in Synthesis Example 2 was added, and a spatula was used. The powder coating composition was prepared by mixing for 2 minutes. The obtained powder coating composition was applied to an iron plate by spraying. Next, this was heated at 180 ° C. for 20 minutes to form a coating film on an iron plate. By measuring the contact angle of this coating,
The results are shown in Table 1.

[0026]

Comparative Example 1 A powder coating composition was prepared in the same manner as in Example 1 except that the powdery mixture obtained in Synthesis Example 1 was not added and blended. The contact angle of the obtained powder coating composition was measured in the same manner as in Example 1, and the results are shown in Table 1.

[0027]

Comparative Example 2 A powder coating composition was prepared in the same manner as in Example 3 except that the powdery mixture obtained in Synthesis Example 2 was not added and blended. The contact angle of the obtained powder coating composition was measured in the same manner as in Example 3, and the results are shown in Table 1.

[0028]

[Table 1]

[0029]

Example 4 To 100 parts of hydrophobic silica having a specific surface area of 110 m ² / g (trade name: R972, manufactured by Nippon Aerosil Co., Ltd.), 50 parts of perfluorooctyl methacrylate which is liquid at 30 ° C. was added, and a dental mixer was used. And mixed for 3 minutes to prepare a fine powder mixture. 2.5 parts of the obtained fine powder mixture was added to 100 parts of an epoxy resin-based powder coating [Toe Corporation; trade name: Toa Powder # 1000] and mixed for 2 minutes to prepare a powder coating composition. Prepared.
The obtained powder coating composition was applied to an iron plate by spraying. Next, this was heated at 180 ° C. for 20 minutes to form a coating film on an iron plate. The contact angle of the coating film was measured, and the results are shown in Table 2.

[0030]

Comparative Example 3 A powder coating composition was prepared in the same manner as in Example 4 except that the fine powder mixture was not added and blended. The contact angle of the obtained powder coating composition was measured in the same manner as in Example 4, and the results are shown in Table 2.

[0031]

Example 5 100 parts of dry-processed silica (carbon content: 4%) having a specific surface area of 150 m ² / g, which had been subjected to surface hydrophobization treatment with hexamethyldisilazane, was charged with the formula: C ₈ F ₁₇ C ₂ H ₄ Si (OCH ₂₎ C
H _{3) 3} was added to 90 parts of perfluorooctyl trimethoxysilane is liquid at 30 ° C. is shown in mixed for 2 minutes using a dental mixer to prepare a powdery mixture. 2 parts of the obtained powdery mixture is coated with a thermosetting polyester resin-based powder coating [Toupe Co., Ltd .; trade name: Powder # 400]
0] and mixed with a dental mixer for 2 minutes to prepare a powder coating composition. The obtained powder coating composition was applied to an iron plate by spraying. Next, this was heated at 200 ° C. for 20 minutes to form a coating film on an iron plate. The contact angle of the coating film was measured, and the results are shown in Table 2.

[0032]

[Table 2]

[0033]

The powder coating additive of the present invention comprises a powdery mixture obtained by mixing a liquid fluorine-containing organic compound with an inorganic fine powder, and has excellent repellency for various powder coatings. Water and oil repellency can be imparted. Further, the powder coating composition of the present invention containing the additive is characterized in that a coating film having excellent water repellency and oil repellency can be formed on various substrate surfaces.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 183/08 C09D 183/08

Claims (7)

[Claims] 1. A mixture of (A) 100 parts by weight of an inorganic fine powder having a specific surface area of 2 m ² / g or more and (B) 1 to 200 parts by weight of a liquid fluorine-containing organic compound in the range of 5 to 50 ° C. An additive for powder coatings comprising the obtained powdery mixture. 2. The composition according to claim 1, wherein the component (A) is selected from the group consisting of silica, alumina and titania.
The additive for powder coating according to the above. 3. The powder coating additive according to claim 1, wherein the component (A) has been subjected to a surface hydrophobization treatment with a silane-based treatment agent in advance. 4. The powder coating additive according to claim 1, wherein the component (B) is a fluorine atom-containing organosilane or a fluorine atom-containing organopolysiloxane. The component (B) is represented by the general formula: {F (CF ₂ ) _a -R ¹ -R ² _b SiO _{(3-b) / 2} } _n (R ³ _c S
iO _{(4-c) / 2} ) _m- (O _1/2 X) _y (wherein, R ¹ is an alkylene group or an alkyleneoxyalkylene group, R ² is the same or different alkyl group or aryl group, R ³ is a substituted or unsubstituted monovalent hydrocarbon group, X is a hydrogen atom or a monovalent hydrocarbon group having 1 to 5 carbon atoms, a is an integer of 4 or more, and b is 0 to 2 C is an integer of 0 to 3, n is a number exceeding 0, and m and y are numbers of 0 or more.) 4. The additive for powder coating according to item 4. 6. The powder coating additive according to claim 1, wherein the additive is used in an amount of not less than 0.1%.
A powder coating composition comprising 1% by weight to 50% by weight. 7. (C) 99.9% by weight to 50% by weight of a resin vehicle for coating selected from the group consisting of epoxy resin, polyester resin and acrylic resin, and (D) inorganic fine powder having a specific surface area of 2 m ² / g or more. 7. A powdery mixture obtained by mixing 100 parts by weight of a body with 1 to 200 parts by weight of a liquid fluorine-containing organic compound within a range of 5 to 50 ° C., comprising 0.1 to 50% by weight. A powder coating composition as described in the above.