JP2001131480A - Wear-resistant, water-repellent coating and article having wear-resistant, water-repellent surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an article having a surface having a high coating film strength, excellent in wear resistance and water-repellent and to provide an wear resistant, water-repellent coating used for forming the water-repellent surface. SOLUTION: The water-repellent coating comprises, as essential ingredients, fine particles of a metal oxide having its surface uniformly fluorinated, a silicone resin, a friction coefficient depressant and a crosslinking agent capable of forming a three-dimensional crosslinking structure by a reaction with a silicone resin. This water-repellent coating is coated on an article to from a water-repellent surface layer having a center line average roughness (Ra) of 0.5 μm or less and excellent in wear resistance and to impart the article with excellent wear resistance and excellent stainproof properties due to the water- repellent surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a coating film having a high strength.
The present invention relates to an article having excellent abrasion resistance and having a water-repellent surface, and a wear-resistant water-repellent paint used for forming the water-repellent surface.

[0002]

2. Description of the Related Art Conventionally, snow and ice prevention of traffic vehicles, aircrafts, road signs, electric wires and cables, antennas, towers, etc., waterproofing of portable electric products and their cases, kitchen appliances around water such as sinks, etc. 2. Description of the Related Art Paints for imparting water repellency to the surface of various articles have been developed for the purpose of preventing water splash dirt, jigs for civil engineering machinery, rain streaks of houses, roads, piers, and the like.

For example, a method of coating a surface with a fluororesin or a silicone resin having a low surface energy, a method of forming a composite plating film of polytetrafluoroethylene oligomer particles on a metal surface (Japanese Patent Laid-Open No. 4-285199, EP
No. 503872), a solid having a water-repellent surface with a multi-step uneven structure including a large-periodic uneven structure on the surface (Japanese Patent Application Laid-Open No. H7-197017), and coupling of a water-repellent substance to a hydrophilic metal surface having a fine uneven structure. For imparting liquid repellency by coating an agent (Japanese Patent Application Laid-Open No. 8-246163, WO96-21523), a water-repellent coating in which a tetrafluoroethylene oligomer powder having an average particle diameter of 4 μm or more or graphite fluoride is dispersed together with a pigment Japanese Unexamined Patent Publication No. Hei 6 (1994) -22838), a coated article obtained by dispersing a powdery additive to give a continuous uneven shape having an average roughness of 0.1 to 100 μm on the coated surface (Japanese Patent Laid-Open No. 7-18209), polytetrafluoro Water-repellent paint in which ethylene low molecular oligomer powder is dispersed (Japanese Patent Laid-Open No. 6-122838), a fluorine resin powder, a binder containing a binder and an additive having a surface free energy smaller than that of the binder Paint (JP-A-9-87574), a coated article obtained by dispersing a powdery additive to give a continuous uneven shape having an average roughness of 0.1 to 100 μm on the coated surface (JP-A-7-18209), A water-repellent coating composition comprising a silicone resin compound and inorganic fine particles (JP-A-4-45181) is known.

However, if the surface is coated only with a fluororesin or a silicone resin, the contact angle of the coating film with water is at most 110 °, and practical water repellency cannot be obtained. The complex plating method, the multi-step uneven structure method, and the method of coating the fine uneven structure with a coupling agent all require complicated pretreatment steps such as plating or surface unevenness, and applicable targets are limited. Problem.

On the other hand, a water-repellent paint in which a tetrafluoroethylene oligomer powder or graphite fluoride having an average particle size of 4 μm or more is dispersed together with a pigment and a powdery additive are dispersed to form a continuous surface having an average roughness of 0.1 to 100 μm on the coating surface. The method of imparting the uneven shape can be used for applications that prevent stains on rain streaks,
For applications requiring high water repellency, such as icing and frost prevention, the water repellency is not sufficient and cannot be used. Incidentally, regarding the latter, the average particle size of the powdery additive is as large as 0.2 to 200 μm, despite the description in the claims, so that the average roughness is 1 μm or less and the contact angle with water is 15 μm.
A coating film of 0 ° or more could not be formed.

A fluororesin paint containing a fluororesin powder, a binder, and an additive having a surface free energy smaller than that of the binder can provide a coating film having high water repellency and no deterioration with time, but the material is extremely expensive. There is a problem that the film strength is low so that it is practically restricted.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a practical means capable of solving the drawbacks of conventional paints and forming a water-repellent surface layer having a coating film strength and abrasion resistance. To provide.

[0008]

Means for Solving the Problems A metal oxide fine particle having a uniformly fluorinated surface, a silicone resin, a friction coefficient reducing agent, and a crosslinking agent capable of forming a three-dimensional crosslinked structure by reacting with the silicone resin are essential. By applying the water-repellent paint contained as a component to an article, a water-repellent surface layer having a center line average roughness (hereinafter referred to as “Ra”) of 0.5 μm or less and having excellent wear resistance is formed. The present inventors have confirmed that the present invention can impart an excellent abrasion resistance and an antifouling property based on a water-repellent surface to an article. That is, the present invention provides an article having the following abrasion-resistant water-repellent paint and abrasion-resistant water-repellent surface layer. 1. Metal oxide particles (A) whose surface is uniformly fluorinated, silicone resin (B), and friction coefficient reducing agent (C)
An abrasion-resistant water-repellent paint containing, as an essential component, a crosslinking agent (D) which reacts with a silicone resin to form a three-dimensional crosslinked structure. 2. The metal oxide whose surface is uniformly fluorinated is Mg,
Al, Si, Ca, Ti, V, Cr, Mn, Fe, C
o, Cu, Zn, Ge, Zr, Ag, In, Sn, P
2. The abrasion-resistant water-repellent coating as described in 1 above, which is obtained by fluorinating a metal oxide containing at least one element selected from the group consisting of b, Sb, Ba, Ta and Ce. . 3. 3. The abrasion-resistant, abrasion-resistant, water-repellent coating according to 1 or 2, wherein the number of silicon atoms having a reactive functional group in the silicone resin is 15% or less of the total number of silicon atoms in the silicone resin. 4. 4. The abrasion-resistant water-repellent coating according to any one of the above items 1 to 3, wherein the solvent contains at least one non-polar organic solvent selected from aliphatic hydrocarbons and aromatic hydrocarbons. 5. The crosslinking agent is represented by the following formula XSi (Y) Z ₂ (wherein X is a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon in which some or all of the hydrogen atoms having 1 to 10 carbon atoms are substituted with fluorine atoms) Y is a hydrocarbon group having 1 to 20 carbon atoms or an alkoxyl group having 1 to 4 carbon atoms, and Z is a group having 1 to carbon atoms.
4 is an alkoxyl group. The abrasion-resistant water-repellent paint according to any one of the above items 1 to 4, which is an alkylsilane represented by the formula 6. (B) / (A) mass ratio of 1.5 to 3.0,
The abrasion-resistant water-repellent coating according to any one of the above items 1 to 5, wherein the mass ratio of (C) / (B) is 0.01 to 0.2. 7. The abrasion resistance according to any one of the above items 1 to 6, which contains a crosslinking agent in an amount of 0.9 to 2.5 times the theoretical reaction amount of the crosslinking agent calculated from the reactive functional group in the silicone resin. Water-repellent paint. 8. 8. The wear-resistant water-repellent paint according to the item 7, wherein the mass ratio of (D) / (B) is 0.03 to 0.6. 9. The abrasion-resistant water-repellent coating according to any one of the above 1 to 8, wherein the nonpolar organic solvent is 65 to 95% by mass of the total amount of the coating. 10. Fine particles of metal oxide having a uniformly fluorinated surface (A), silicone resin (B), and friction coefficient reducing agent (C)
And a crosslinking agent (D) capable of reacting with B to form a three-dimensional crosslinked structure as an essential component, wherein B and D form a three-dimensional crosslinked structure. Water-repellent coating. 11. An article in which the coating according to item 10 is formed on part or all of the surface. 12. The metal oxide whose surface is uniformly fluorinated is represented by M
g, Al, Si, Ca, Ti, V, Cr, Mn, Fe,
Co, Cu, Zn, Ge, Zr, Ag, In, Sn, P
The abrasion-resistant water-repellent surface according to the above item 11, which is obtained by fluorinating a metal oxide containing at least one element selected from the group consisting of b, Sb, Ba, Ta and Ce. Article having a layer. 13. 13. The article having an abrasion-resistant water-repellent surface layer according to 11 or 12, wherein the number of silicon atoms having a reactive functional group in the silicone resin is 15% or less of the total number of silicon atoms in the silicone resin. 14． The crosslinking agent is represented by the following formula XSi (Y) Z ₂ (where A is
Is a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group in which a part or all of hydrogen atoms having 1 to 10 carbon atoms are substituted with fluorine atoms, and B is a hydrocarbon group having 1 to 20 carbon atoms or carbon An alkoxyl group having 1 to 4 carbon atoms, wherein C is 1 carbon atom
To 4 alkoxyl groups. 14. The article having an abrasion-resistant water-repellent surface layer according to any one of 11 to 13, which is an alkylsilane represented by 15. The mass ratio of (B) / (A) is 1.5 to 3.0, and the mass ratio of (C) / (B) is 0.01 to 0.2.
An article having an abrasion-resistant water-repellent surface layer according to any one of the above items 11 to 14. 16. The abrasion-resistant water repellent according to any of the above items 11 to 15, which contains a crosslinking agent in an amount of 0.9 to 2.5 times the theoretical reaction amount of the crosslinking agent calculated from the reactive functional group in the silicone resin. An article having a surface layer. 17． 17. The article having the wear-resistant water-repellent surface layer according to the above item 16, wherein the mass ratio of (D) / (B) is 0.03 to 0.6. 18. The wear-resistant water-repellent material according to any of the above items 11 to 17, wherein the article is selected from a metal structure, a glass structure, a fiber structure, a ceramic structure, a wood material, a plastic structure, and a wall structure. An article having a surface layer. 19. A method for applying an abrasion-resistant water-repellent surface to an article by applying the abrasion-resistant water-repellent surface according to any one of the above items 1 to 9 to the article. In the present invention,
The term “water-repellent surface” refers to a surface state in which the contact angle of a substance surface with a water droplet is 140 ° or more. The water-repellent surface having a contact angle of 140 ° or more and having a smooth property exhibits an antifouling function that can be easily washed off by rainwater or a stream of water even if dirt composed of inorganic fine particles such as dust adheres. If the contact angle is less than 140 °, such a function is not exhibited.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As the fine particle material used in the coating material of the present invention, metal oxide particles whose surface is uniformly fluorinated (hereinafter referred to as “uniformly fluorinated”) are used. Specific examples of metal oxides include Mg, Al, Si,
Ca, Ti, V, Cr, Mn, Fe, Co, Cu, Z
n, Ge, Zr, Ag, In, Sn, Pb, Sb, B
at least one selected from the group consisting of a, Ta and Ce
Oxides containing seed elements can be mentioned. For more information,
MgO, Al ₂ O ₃ , SiO ₂ , CaO, TiO ₂ , V
₂ O ₅ , CrO, Cr ₂ O ₃ , MnO, Mn ₂ O ₃ , Mn
O ₂ , Mn ₃ O ₄ , Fe ₂ O ₃ , Fe ₃ O ₄ , CoO, Co ₃ O
₄ , Cu ₂ O, CuO, ZnO, GeO ₂ , ZrO ₂ , Ag
₂ O, InO, In ₃ O ₄ , SnO, SnO ₂ , Pb ₃ O ₄ ,
PbO ₃ , Sb ₂ O ₃ , SbO ₂ , Sb ₂ O ₅ , BaTi
O ₃ , TaO ₂ , Ta ₂ O ₅ , CeO ₂ , CaTiO ₃ and F
A metal oxide containing at least one element selected from the group consisting of eTiO ₃ can be given. Among these, preferred examples are Ti, Al, Si, Ce, Zr,
Examples include metal oxides containing at least one element selected from the group consisting of Zn, Sn, and Fe.

The metal oxide particles whose surface is uniformly fluorinated used in the present invention have a specific surface area of 3 to 300 m ^2.
/ G is preferable. The average primary particle size is not particularly limited, but is preferably 1 to 200 nm.
And more preferably 5 to 100 nm. Also,
There is no particular limitation on the crystal form of the particles. Amorphous body,
There are no restrictions on single crystals, polycrystals, etc., and there are no restrictions on amorphous, anatase, brookite, rutile and known titanium oxides, and also on α-type and γ-type known alumina. Absent.

[0011] Uniformly fluorinated metal oxide particles have good dispersibility when incorporated into a coating material as a water-repellent material, and after curing, the particles are present at a high concentration on the surface.
A uniform and excellent water-repellent coating film can be formed. Here, “uniformly” of the metal oxide particles whose surfaces are uniformly fluorinated means that the surfaces of the metal oxide particles are uniformly fluorinated, but not necessarily the entire metal oxide particles ( (Bulk) need not be 100% fluorinated. That is, on the surface of the metal oxide particles, the F ratio in a certain depth direction from the surface layer does not vary on the surfaces of different particles or the same particles, in other words, the fluorinated on the surfaces of all the particles. This means that there are no unexposed parts or parts that do not reach the desired fluorination rate. Incidentally, the fluorination rate on the surface of the metal oxide particles is determined by XPS (X-ray photoelectron spectr).
Oscopy: X-ray photoelectron spectroscopy, 10 kV, 20 mA, irradiation area 100 μm ² ) can measure fluorine-containing elements existing from the particle surface to a depth of about 100 Å, and the ratio of substituted fluorine from the analysis results Is required. In the present invention, the fluorination rate is represented by the number ratio of substituted fluorine atoms to the metal atoms in the metal oxide = F / M (F: the number of fluorine atoms, M: the number of metal element atoms), F / M is preferably 0.05 or more.

Generally, the surface of the metal oxide fine particles is covered with a surface functional group such as a hydroxyl group, which causes the surface to be hydrophilic, adsorb moisture, and have high cohesiveness and adhesion. Surface fluorination lowers the surface free energy by substituting these surface hydroxyl groups with fluorine groups, so that the surface properties that are practically preferable for powders, that is, powder fluidity, dispersibility in solvents and the like, and low moisture absorption ( Water) or water repellency. Therefore, it is optimal that substantially all surface hydroxyl groups are substituted by fluorine groups. For example, in the case of fluorinated silica, the fluorination rate F / Si is 0.10
By doing so, the Si—OH bond disappears, and instead, Si
-F bonds are formed. This can be confirmed by appropriate analytical means such as ²⁹ Si-NMR or infrared spectrum. The fluorination rate of uniformly fluorinated metal oxide particles blended in the paint and the properties of the coating film have a correlation. If the same amount is used, metal oxide particles with a high fluorination rate are used. The higher the water repellency, the lower (smooth) the average roughness of the coating film.

With metal oxide particles that have not been surface-treated, only a water-repellent coating film having a large average roughness due to aggregated particles can be obtained. Further, in the case of conventional surface-hydrophobic metal oxide particles such as hydrophobic silica, a non-hydrophobic portion appears due to high dispersion, and only a coating film having a large deterioration in water repellency with time can be obtained.

The silicone resin used as a binder in the paint of the present invention is not particularly limited. For example, a modified silicone resin such as a straight silicone resin, an acrylic silicone resin, an alkyd silicone resin, and a polyester silicone resin can be used. Among them, a straight silicone resin is preferably used. Further, a straight silicone resin in which the number of silicon atoms having a reactive functional group in the silicone resin is 15% or less of the total number of silicon atoms in the silicone resin can provide a coating material with less water-repellent deterioration over time, Particularly preferred.

As the third component of the paint of the present invention, a friction coefficient reducing agent (a paint additive also called as a frictional resistance reducing agent, a wear resistance imparting agent or a slip property improving agent) is used. These are polyether-modified silicone oil, higher fatty acid-modified silicone oil, alkyl-modified silicone oil,
A substance containing a modified silicone oil such as a fluorine-modified silicone oil as an active ingredient. Specifically, KP301, KP302, KP305, KP30 manufactured by Shin-Etsu Silicone Co., Ltd.
6. DC11PA, SH28 manufactured by Dow Corning Toray
PA, ST103PA, TSF44 manufactured by Toshiba Silicone Co., Ltd.
60, TSF4452, TSF410, TSF411,
And the like. The addition of these compounds not only improves the smoothness and lubricity of the coating, but also surprisingly works in concert with uniformly fluorinated metal oxide particles to further increase the water repellency of the coating. And the effect of reducing the deterioration over time of the water repellency.

As the fourth essential component of the paint of the present invention, a crosslinking agent capable of reacting with the silicone resin to form a three-dimensional crosslinked structure is used. As a crosslinking agent, the following formula XS
i (Y) Z ₂ (wherein X is a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group in which some or all of the hydrogen atoms having 1 to 10 carbon atoms are substituted with fluorine atoms, and Y is An alkylsilane represented by a hydrocarbon group having 1 to 20 carbon atoms or an alkoxyl group having 1 to 4 carbon atoms, and Z is an alkoxyl group having 1 to 4 carbon atoms) is preferably used.

Specifically, CH_ThreeSi (OCH_Three)_Three, C
H_ThreeSi (OC_TwoH_Five)_{Three ,} (CH_Three)_TwoSi (OCH_Three)_Two,
(CH_Three)_TwoSi (OC_TwoH_Five)_{Two ,}, CH_Three(CH_Two)₁₇Si
(OCH_Three)_Three, CH_Three(CH_Two)₁₇SiCH_Three(OCH_Three)
_Two, CH_Three(CH_Two)₁₇Si (OC_TwoH_Five)_Three, CF_Three(C
H_Two)_TwoSi (OCH_Three)_Three, CF_Three(CF_Two)_Five(CH_Two)_Two
Si (OCH_Three)_Three, CF_Three(CF_Two)₇(CH_Two)_TwoSi
(OCH_Three)_Three, CF_Three(CF _Two)₇(CH_Two)_TwoSiCH
_Three(OCH_Three)_Two And the like.

As the solvent for the coating material of the present invention, one or more organic solvents selected from the group consisting of saturated hydrocarbon-based and aromatic hydrocarbon-based nonpolar organic solvents are used. For example, hexane, heptane, methylhexane, octane, trimethylpentane, nonane, toluene, xylene, ethylbenzene, cyclohexane, methylcyclohexane and the like can be mentioned.

In the coating material of the present invention, the mass ratio of the silicone resin to the particles of the surface-fluorinated metal oxide is in the range of 1.5 to 3.0, preferably 2.0 to 2.0.
5 range. And the mass ratio of the friction coefficient reducing agent / active ingredient to the silicone resin binder is 0.01 to
It is in the range of 0.2, preferably in the range of 0.02 to 0.1. When the composition is out of the above range, a water-repellent coating film having an average roughness of 0.5 μm or less, having smoothness, lubricity and excellent abrasion resistance cannot be obtained. For example, if the mass ratio of the silicone resin to the fine particles of the metal oxide whose surface is fluorinated is less than 1.5, the coating film strength is not sufficient, and a coating film having abrasion resistance cannot be obtained. If it exceeds 3.0, the antifouling function of the water-repellent coating film cannot be sufficiently exhibited. Further, if the mass ratio of the friction coefficient reducing agent / active ingredient to the silicone resin binder is less than 0.01, the effect of addition is not sufficiently exhibited, and if it exceeds 0.2, cracks, peeling, powder blowing, etc. of the coating film occur. And a practical coating film cannot be obtained. The cross-linking agent is 0.9 to the theoretical reaction amount of the cross-linking agent calculated from the content of the reactive functional group of the silicone resin binder.
Add ~ 2.5 times the amount of crosslinking agent. If it is less than 0.9 times, the abrasion resistance effect is not clearly exhibited, and if it exceeds 2.5 times, the water repellency of the coating film decreases, and the antifouling function of the water repellent coating film cannot be sufficiently exhibited. Since it depends on the molecular weight of the crosslinking agent, it cannot be unconditionally determined, but is generally added in a mass ratio of 0.03 to 0.6 with respect to the silicone resin binder. The amount of the solvent added is 65 to 95% by mass of the total coating weight.
If it is less than 65%, the coating film may be cracked or peeled by the naked eye, and a practical coating film may not be obtained. If it is 95% or more, it is difficult to form a continuous coating film without defects.

A general method can be used for preparing the paint. The means for dispersing the paint components is not particularly limited, and for example, a roll mill, a ball mill, an attritor, a sand mill, a coball mill, a basket mill, a paint shaker, and the like can be used. In the coating composition of the present invention, since the ratio of the fine powder material to the binder is large, in order to form a coating film having high smoothness and high water repellency, the metal oxide particles are sufficiently dispersed to be close to the primary particle size. It is desirable to disperse to the state. For this reason, a method of dispersing metal oxide particles in a solvent, then adding another paint component and redispersing the same is preferably used. Dispersion conditions vary depending on the particle size of the metal oxide particles, liquid viscosity, dispersion means, etc.
Although it is not unequivocally determined, for example, uniformly fluorinated silica (primary particle size: 20 nm) is added to the solvent at 10% by mass, zirconia beads are added three times the total liquid weight, and the mixture is treated with a paint shaker for 1 hour. Then, by measuring the 50% particle size using a particle size analyzer (Microtrac UPA),
It has been found that the particles are dispersed to a substantially primary particle size. If the same dispersion share is applied to other dispersion means, the same dispersion state can be obtained.

To apply the paint of the present invention, a usual coating method can be used.
Dipping, spin coater and the like are preferable. Spray coating is easy to obtain a highly water-repellent coating film having large surface irregularities, but it is difficult to obtain a water-repellent coating film having excellent abrasion resistance and high surface smoothness according to the present invention. The method for curing the coating film is set so that the crosslinking reaction between the silicone resin and the crosslinking agent proceeds sufficiently. Usually, heat curing is used. The curing temperature can not be determined unequivocally, but if performed at too high a temperature,
The crosslinking agent volatilizes and is not economical.

By applying the wear-resistant water-repellent paint according to the present invention to the article, the center point average roughness Ra is 0.5 μm.
m, a surface layer having abrasion resistance and a water repellency having a contact angle with water of 140 ° or more can be formed. Since the surface layer has abrasion resistance, even if the surface is rubbed or a physical force is applied, the water-repellent coating on the surface is not destroyed, and the water-repellency is easily deteriorated. There is no such thing. In addition, the surface layer of the present invention has not only a water repellency having a contact angle to water of 140 ° or more but also a fine crack unique to a silicone resin coating film containing fine particles, and an average roughness of 0.5 μm or less. With high surface smoothness. Therefore, even if dirt made of inorganic fine particles such as dust adheres, the dirt can be easily washed off with rainwater or a water stream, and exhibits an antifouling function of reducing the adhesion of various dirt contained in rainwater. Contact angle is 1
If the angle is less than 40 °, such a function is not exhibited. further,
Due to the decrease in the coefficient of surface friction, snowfall and dropping properties are improved, and snow and ice accretion are excellent.

In the present invention, "surface layer" means that a highly water-repellent coating layer is present on the outermost layer of the article. The abrasion-resistant water-repellent paint of the present invention may be applied directly to the surface of the base material, or the abrasion-resistant water-repellent paint of the present invention may be applied after being subbed with another paint. . The undercoat is not particularly limited as long as it has good adhesion to the abrasion-resistant water-repellent paint of the present invention and does not impair the characteristics of the abrasion-resistant water-repellent paint.

The surface uneven structure of the article provided with the water-repellent surface layer according to the present invention is not particularly limited, and the uniformly fluorinated metal oxide particles present on the article surface and other paint components are used. High water repellency is created by the fine uneven structure formed. Specific examples of the article coated with the wear-resistant water-repellent paint of the present invention include metal structures, light metal structures, glass structures, fiber structures, ceramic structures, wood structures, plastic structures, Wall structures and the like.

[0025]

The present invention will be described in detail below with reference to examples. However, the present invention is not limited by these examples.

In the following examples, the surface condition was measured by the following method or means. (1) X-ray photoelectron spectroscopy (XPS)
Quantified by The result was obtained by the number ratio F / M of the fluorine atom to the metal atom of the metal oxide (MOx). (2) The water repellency of the coating film surface was measured by measuring the contact angle with distilled water (10 μl). As a contact angle measuring device, CA-DT type manufactured by Kyowa Interface Science Co., Ltd. was used. (3) Surfline MST-301 manufactured by Mitutoyo Corporation was used to measure the center line average roughness of the coating film surface. (4) A high-resolution digital microscope VH-6300 manufactured by KEYENCE CORPORATION was used for observation of minute cracks in the coating film (magnification: 2000 times). The results were determined based on the following three criteria. ○: No cracks △: Partially fine cracks X: Continuous large cracks (5) The dynamic friction coefficient of the coating film was measured using a surface property measuring instrument HEIDON-14DR manufactured by Shinto Kagaku Co., Ltd. Load of 22.2 g / cm ^{2 with} ASTM plane indenter, moving speed 200 mm /
min. And a moving distance of 20 mm. (6) Abrasion resistance was measured using Shinto Kagaku Co., Ltd.
Using an EIDON-14DR type, an acrylic plate (50 mm × 50 mm) was fixed to an ASTM plane indenter with double-sided tape, a load of 8 g / cm ² , and a moving speed of 200 mm / min. It was reciprocated repeatedly (up to 100 times) under the condition of a moving distance of 20 mm, and the frictional resistance and the change in the surface state were measured. The number of reciprocations at which the frictional resistance changed was recorded, and the surface condition after the test was observed. ○: No change ×: Surface scraping and flaws (7) Ash adhesion test was performed by the following method. That is, a 10% dispersion obtained by dispersing the ash in ethanol is applied to the surface of the coating film (the amount of ash attached 0.5 g / c).
m ² ), and dried at 80 ° C. for 1 hour. The coating film with the sticks was placed horizontally, and distilled water was sprayed from above with a single-particle spray (flow rate 100 ml / min). After 6 minutes, the surface of the coating film is cleaned with a high-resolution digital microscope VH-6300 manufactured by KEYENCE.
Observed using a mold. The results were determined based on the following three criteria. That is: No residue or less than 5% of the residue of the sawdust. Δ: There is a residue of the residue (5 to 20% of the residue area). X: A large amount of residue of the residue of the residue (20% or more of the residue area). Method. That is,
Place artificial snow made by crushing ice finely on the coating (0.5g
/ Cm ² ), the coating film was gradually inclined, and the inclination at which artificial snow began to fall (hereinafter referred to as a falling angle) was measured. The measurement was performed in a refrigerator at −5 ° C. in a state where samples, instruments, and the like were cooled to room temperature. Production Example: Production of Fluorinated Metal Oxide A 40 L tumble dryer was charged with 320 g of titanium oxide particles (F6, manufactured by Showa Titanium, average primary particle size: 16 nm, specific surface area: 100 m ² / g), and the pressure was reduced to 18
Pre-treated by firing at 0 ° C. for 1 hour, cooled to room temperature, filled with a gas obtained by diluting fluorine gas with nitrogen gas at normal pressure (fluorine gas content: 10% by volume), and rotating at 60 rpm for 180 hours. The surface was fluorinated at 5 ° C. for 5 hours. The same fluorination treatment was performed a total of five times. The specific surface area of the fluorinated titanium oxide particles is 99 m ² / g,
High specific surface area was maintained. The fluorination rate of the titanium oxide particles measured by XPS was fluorination rate F / Ti = 0.88. Similarly, silica (130 manufactured by Nippon Aerosil, specific surface area: 130 m ² / g, primary particle size 16 nm) and aluminum oxide (alumina) (manufactured by Nippon Aerosil, specific surface area: 100 m ² / g, primary particle size 1)
(3 nm). Table 1 shows the physical properties of these uniformly fluorinated metal oxide particles.

[0027]

[Table 1] Example 1 34.36 g of n-octane was obtained from 2.81 g of uniformly fluorinated silica particles having an average primary particle diameter of 20 nm obtained in Production Example.
And dispersed with a paint shaker for 1 hour. 11.25 g of a straight silicone resin (SR2400, manufactured by Toray Dow Corning, solid content 50%), a friction coefficient reducing agent (KP302, manufactured by Shin-Etsu Silicone, solid content 10)
%) 0.80 g, crosslinking agent (trifluoromethylethyltrimethoxysilane; AY43-0 manufactured by Toray Dow Corning Co., Ltd.)
13) 0.80 g was added, and the mixture was dispersed with a pane shaker for an additional 15 minutes. The above paint was applied to a glass substrate with a bar coater and cured at 150 ° C. for 1 hour. The film thickness after curing was about 10 μm. The coating film was subjected to a surface contact angle, average roughness, dynamic friction coefficient, abrasion resistance test, ash adhesion test, and snow fall test. Table 2 shows the results.

[0028]

[Table 2] Examples 2 to 19 In the same manner as in Example 1, coating materials having the compositions shown in Tables 2 to 4 were prepared, and coating films were formed on glass substrates. The coating properties were measured in the same manner as in Example 1. Tables 2 to 4 show the results.

[0029]

[Table 3]

[Table 4] By applying the abrasion-resistant water-repellent paint according to the present invention to an article, the center point average roughness Ra is 0.5 μm or less, abrasion-resistant, and the contact angle to water is 140 °.
A surface layer having the above water repellency can be formed.
The surface layer is not only water-repellent, but also has no fine cracks specific to the conventional silicone resin-containing water-repellent coating,
High surface smoothness. Further, the surface layer of the present invention has an average roughness of 0.5 μm or less, so that various types of dirt are less attached and the antifouling property is high. Furthermore, since it has a low surface friction coefficient, it has snow falling properties and is excellent in snow resistance and icing resistance. From the results of the abrasion resistance test, snow fall test and ash adhesion test, the excellent wear resistance, antifouling property and snow fall property of the coating film of the present invention are apparent. Comparative Examples 1 to 5 In Comparative Examples 1 to 5, paints and coating films were prepared in the same manner as in Examples 1, 4, 7, 18, and 19, respectively, except that no crosslinking agent was added. . The coating film properties were measured in the same manner as in Example 1, and the results are shown in Table 5. The wear resistance is
It is significantly inferior to the coating film of the present invention, and a change in frictional resistance is seen after 20 or less reciprocating movements, and the surface coating film is significantly scraped.

[0030]

[Table 5] Comparative Examples 6 to 13 In the same manner as in Example 1, coating materials having the compositions shown in Table 3 were prepared, and coating films were formed on glass substrates. The coating film properties were measured in the same manner as in Example 1, and the results are shown in Table 6. When the mass ratio of the binder to the metal oxide fine particles is less than 1.5, the abrasion resistance is not sufficient, and when it exceeds 3, the water repellency is reduced, and the antifouling function evaluated by the ash adhesion test is reduced. When the amount of the crosslinking agent is excessive, the antifouling function is reduced. When the amount of the crosslinking agent is insufficient, the abrasion resistance is insufficient.

[0031]

[Table 6]

According to the present invention, metal oxide particles having a surface uniformly fluorinated, a silicone resin, a friction coefficient reducing agent, and a crosslinking agent which reacts with the silicone resin to form a three-dimensional crosslinked structure are contained. By providing the article with a water-repellent surface layer having a center point average roughness (Ra) of 0.5 μm or less and a contact angle to water droplets of 140 ° or more, the article has an improved abrasion resistance and a water-repellent surface. Based antifouling function. The article having the surface layer exhibits excellent antifouling property and durability.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F006 AB39 AB67 AB74 BA02 BA11 DA04 4H020 AA03 AB01 BA11 BA32 BA36 4J038 DL031 DL072 DL152 HA166 HA196 HA206 HA216 HA446 JA02 JA03 JC32 KA03 KA06 KA07 KA15 KA20 NA05 NA07 PC03 PC08 PC02 PC10

Claims (19)

[Claims] 1. Crosslinking which forms a three-dimensional crosslinked structure by reacting a metal oxide particle (A) whose surface is uniformly fluorinated, a silicone resin (B), and a friction coefficient reducing agent (C) and (B). A wear-resistant water-repellent paint containing the agent (D) as an essential component. 2. A metal oxide whose surface is uniformly fluorinated is Mg, Al, Si, Ca, Ti, V, Cr, Mn,
Fe, Co, Cu, Zn, Ge, Zr, Ag, In, S
The abrasion resistance according to claim 1, wherein the metal oxide is obtained by fluorinating a metal oxide containing at least one element selected from the group consisting of n, Pb, Sb, Ba, Ta and Ce. Water repellent paint. 3. The number of silicon atoms having a reactive functional group in the silicone resin is 15% of the total number of silicon atoms in the silicone resin.
% Or less. 4. The abrasion-resistant water-repellent coating according to claim 1, wherein the solvent contains at least one non-polar organic solvent selected from aliphatic hydrocarbons and aromatic hydrocarbons. 5. A crosslinking agent represented by the following formula XSi (Y) Z ₂ (where X is a hydrocarbon group having 1 to 20 carbon atoms or 1 to 2 carbon atoms)
Y is a hydrocarbon group having 1 to 20 carbon atoms or an alkoxyl group having 1 to 4 carbon atoms, and Z is a hydrocarbon group in which some or all of 10 hydrogen atoms are substituted with fluorine atoms. To 4 alkoxyl groups. 5. The abrasion-resistant water-repellent paint according to claim 1, which is an alkylsilane represented by the formula (1). 6. The mass ratio of (B) / (A) is from 1.5 to 3.0.
And the mass ratio of (C) / (B) is 0.01 to
The wear-resistant water-repellent paint according to any one of claims 1 to 5, which is 0.2. 7. The theoretical reaction amount of the crosslinking agent calculated from the reactive functional group equivalent in the silicone resin is 0.9 to 2.5.
The abrasion-resistant water-repellent coating according to any one of claims 1 to 6, comprising a double amount of a crosslinking agent. 8. The mass ratio of (D) / (B) is from 0.03 to 0.5.
The abrasion-resistant water-repellent coating according to claim 7, which is 6. 9. The non-polar organic solvent is used in an amount of from 65 to 95 of the total amount of the paint.
The abrasion-resistant water-repellent coating according to any one of claims 1 to 8, which is a mass%. 10. A three-dimensional crosslinked structure is formed by reacting fine particles (A) of a metal oxide whose surface is uniformly fluorinated, a silicone resin (B), and a friction coefficient reducing agent (C) and (B). An abrasion-resistant water-repellent coating characterized by comprising a crosslinking agent (D) as an essential component, wherein (B) and (D) form a three-dimensional crosslinked structure. 11. An article wherein the coating film according to claim 10 is formed on a part or all of the surface. 12. A metal oxide whose surface is uniformly fluorinated is Mg, Al, Si, Ca, Ti, V, Cr, Mn,
Fe, Co, Cu, Zn, Ge, Zr, Ag, In, S
The antifouling / repellent material according to claim 11, which is obtained by fluorinating a metal oxide containing at least one element selected from the group consisting of n, Pb, Sb, Ba, Ta and Ce. An article having a water surface layer. 13. The number of silicon atoms having a reactive functional group in the silicone resin is one of the total number of silicon atoms in the silicone resin.
The article having an abrasion-resistant water-repellent coating layer according to claim 11 or 12 which is 5% or less. 14. The crosslinking agent of the following formula XSi (Y) Z ₂
(Wherein, X is a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group in which some or all of the hydrogen atoms having 1 to 10 carbon atoms are substituted with fluorine atoms, and Y is a hydrocarbon group having 1 to 20 carbon atoms. A hydrocarbon group or an alkoxyl group having 1 to 4 carbon atoms;
Is an alkoxyl group having 1 to 4 carbon atoms. The article having an abrasion-resistant water-repellent surface layer according to any one of claims 11 to 13, which is an alkylsilane represented by the following formula: 15. The mass ratio of (B) / (A) is from 1.5 to 3.
0, and the mass ratio of (C) / (B) is 0.01 to
An article having an abrasion-resistant water-repellent surface layer according to any one of claims 11 to 14, which is 0.2. 16. The anti-crosslinking agent according to claim 11, wherein the crosslinking agent is contained in an amount of 0.9 to 2.5 times the theoretical reaction amount of the crosslinking agent calculated from the reactive functional group in the silicone resin. An article having an abrasive water-repellent surface layer. 17. The mass ratio of (D) / (B) is from 0.03 to
An article having an abrasion-resistant water-repellent surface layer according to claim 16, which is 0.6. 18. The article according to claim 11, wherein the article is selected from a metal structure, a glass structure, a fiber structure, a ceramic structure, a wood material, a plastic structure, and a wall structure. An article having an abrasive water-repellent surface layer. 19. A method for imparting an abrasion-resistant water-repellent surface to an article by applying the abrasion-resistant water-repellent paint according to any one of claims 1 to 9 to the article.