JP3773464B2 - Water repellent treatment - Google Patents

Description

【発明の効果】
本発明の撥水処理剤によれば、処理対象物に対して超撥水性を付与することができ、しかも、十分な透明性を確保することができる。そのため、本発明の撥水処理剤は、雨水のかかる屋外で用いられ、安全のために優れた透明性（光透過率が７０％以上）が要求される部材、例えば、自動車のサイドミラー、路上のカーブミラーなどの表面を処理し、雨水の付着を防止するための撥水処理剤として、好適に用いることができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water repellent treatment agent, and more particularly to a water repellent treatment agent used for surface treatment of a side mirror of an automobile.
[0002]
[Prior art]
In recent years, various super-water-repellent paints exhibiting remarkable water repellency against water have been proposed. For example, JP-A-11-29722 discloses inorganic or organic fine particles, a coupling agent, a binder resin, and a solvent. The contained water-repellent paint exhibits a super-water-repellent property with a contact angle of 140 ° or more. For example, if such a super-water-repellent paint is applied to structures installed outdoors such as various antennas and cables, It is described that excellent super water repellency can prevent water wetting, dirt, corrosion, and ice / snow adhesion.
[0003]
On the other hand, for example, in a side mirror of an automobile, it is known to treat the surface of the mirror with a water repellent treatment agent in order to prevent the attachment of rainwater. Development of a water repellent treatment agent exhibiting such super water repellency has been desired.
[0004]
[Problems to be solved by the invention]
However, for example, even if the surface of the mirror is treated with a super water-repellent coating described in JP-A-11-29722, it is difficult to achieve super water repellency, and the mirror surface is transparent. Therefore, it is unsuitable to use the above super-water-repellent paint for such applications.
[0005]
In other words, automobile side mirrors are originally installed for safety confirmation, and even if a thick coating film is formed on the surface of the mirror, it is difficult to achieve super water repellency, and If the transparency is lowered even a little, the original function of the mirror is disturbed and the safety is greatly affected.
[0006]
Therefore, the present invention has been made in view of such problems, and the object of the present invention is to provide water repellency that can provide excellent water repellency and can ensure sufficient transparency. It is to provide a treatment agent.
[0007]
[Means for Solving the Problems]
  In order to achieve the above object, the water repellent treatment agent of the present invention comprises:It contains inorganic or organic fine particles having a primary average particle size of less than 10 nm, a coupling agent, an acid, a resin, and a solvent, and at least the inorganic or organic fine particles are dispersed by ultrasonic waves or high-speed turbulent energy. , A water repellent treatment agent that contains a coupling agent and is obtained as a secondary average particle diameter of 50 nm or less, and the resin is an acrylic resin, polystyrene resin, polycarbonate resin, polyester resin, polyethylene resin, polypropylene resin, It is at least one resin selected from the group consisting of a polyamide resin, a polyurethane resin, an acrylic-butadiene-styrene copolymer (ABS) resin, and a vinyl acetate resin, and the coupling agent is a fluoro represented by the general formula (1) An alkylsilane compound,
YRSiX ₃ (1)
Wherein Y is a fluorinated alkyl group having 2 to 12 carbon atoms, R is an alkylene group having 2 to 4 carbon atoms, X is the same or different, and an alkoxy group having 1 to 4 carbon atoms or a chlorine atom Or any one of alkyl groups having 1 to 4 carbon atoms, except that X is an all alkyl group.) The amount of inorganic or organic fine particles is 0.3 in the water repellent treatment agent. ~ 5% by weight,
The amount of the coupling agent is 0.00001 to 0.1% by weight when the inorganic or organic fine particles are previously subjected to hydrophobic treatment in the water-repellent treatment agent. When the hydrophobic treatment is not performed, the amount is 0.2 to 4% by weight, the amount of the resin is 0.001 to 0.1% by weight in the water-repellent treatment agent, and light is transmitted at a wavelength of 600 nm. Used for the surface treatment of members that require a rate of 70% or moreIt is characterized by.
[0008]
  The water repellent treatment agent of the present invention isThe resin is a silicone-acrylic resinIt is preferable.
[0009]
  The water repellent treatment agent of the present invention isThe amount of the acid is 0.00001 to 0.1% by weight in the water repellent treatment agent.It is preferable.
[0012]
And the water repellent agent of this invention can be preferably used for the surface treatment of a mirror.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
  The water repellent treatment agent of the present invention comprises inorganic or organic fine particles having a primary average particle size of less than 10 nm, a coupling agent, an acid,resinAnd contains a solvent.
[0014]
The fine particles are not particularly limited, and include inorganic fine particles and organic fine particles. Examples of the inorganic fine particles include silica fine particles such as ultrafine anhydrous silica, shirasu, and quartz glass, and metal fine particles such as aluminum oxide and titanium oxide. Examples of the organic fine particles include cross-linked polymers such as polymethyl methacrylate.
[0015]
These fine particles can be used singly or in combination, and ultrafine anhydrous silica is preferably used.
[0016]
Furthermore, among the ultrafine anhydrous silica, those whose surfaces have been subjected to hydrophobic treatment in advance are preferably used. Examples of such ultrafine particulate anhydrous silica that has been subjected to hydrophobic treatment in advance include, for example, Aerosil R976S, Aerosil R812, RY300, RX300, R812S, R976 (manufactured by Nippon Aerosil Co., Ltd.). . By using ultrafine particulate anhydrous silica that has been hydrophobically treated in advance, it has better dispersibility, workability and economy than hydrophilic silica (silica having an OH group on the surface) that has not been previously hydrophobically treated. It is possible to improve the performance.
[0017]
The fine particles have a primary average particle size of less than 10 nm, preferably 5 to 8 nm. When the primary average particle diameter is 10 nm or more, the transparency is lowered and cannot be used as a water repellent treatment agent that can ensure transparency such as poor visibility.
[0018]
The primary average particle size means not the apparent particle size in the aggregated state but the average particle size of each primary particle in the fine particle group in the aggregated state. That is, the fine particles actually have a plurality of primary particles agglomerated (that is, sticking to each other), and apparently form a powder. It means not the apparent particle size of the powder but the average particle size of each primary particle forming the powder. Since the primary average particle size is small, the electron microscopic observation is the only direct method for confirming the particle size. Specifically, for example, by electron microscopic observation, The obtained observation image can be calculated by reading it into a personal computer, measuring 3000 or more particles with a computer caliper, and determining the average diameter.
[0019]
The coupling agent is not particularly limited, and examples thereof include a silane coupling agent and a titanium coupling agent, and a fluorine-based silane coupling agent is preferably used. By using the fluorine-based silane coupling agent, the contact angle of the polka dots can be improved as compared to using other coupling agents.
[0020]
Examples of the fluorine-based silane coupling agent include a fluoroalkylsilane compound represented by the general formula (1).
[0021]
YRSiX3 (1)
(Where Y is the number of carbon atoms2-12 fluorinated alkyl groups, R is carbon number2-4 alkylene group, X is the same or different, and represents either an alkoxy group having 1 to 4 carbon atoms, a chlorine atom or an alkyl group having 1 to 4 carbon atoms.However, X excludes the case where all are alkyl groups.More specifically, for example, CF_ThreeCF₂CH₂CH₂Si (OC_ThreeH₇)_Three, CF_Three (CF₂)₂CH₂CH₂Si (OC_ThreeH₇)_Three, CF_Three(CF₂)_FourCH₂CH₂Si (OC₂H_Five)_Three, CF_Three (CF₂)_FourCH₂CH₂SiCH_Three(OC₂H_Five)₂, CF_Three (CF₂)_FourCH₂CH₂SiCH_Three (OC_ThreeH₇)₂, CF_Three (CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three, CF_Three (CF₂)_FiveCH₂CH₂SiCH_Three(OC_ThreeH₇)₂, CF_Three (CF₂)₇CH₂CH₂Si (OC₂H_Five)_Three, CF_Three (CF₂)₇CH₂CH₂Si (OCH_Three)_Three, CF_Three (CF₂)₇CH₂CH₂SiCH_Three(OC_ThreeH₇)₂And perfluoroalkylalkylene alkoxysilane compounds.
[0022]
These coupling agents can be used alone or in combination.
[0023]
Examples of the acid include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as acetic acid and formic acid. These acids can be used alone or in combination. By using an acid, hydrolysis of the coupling agent can be promoted to form a strong bond between the fine particles and the coupling agent.
[0024]
Although it does not specifically limit as a solvent, For example, alcohol, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, For example, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol Examples include glycols such as monoethyl ether. These solvents can be used singly or in combination, and alcohols are preferably used.
[0025]
  The water repellent treatment agent of the present invention further contains a resin.TheAs resinAKuryl resin, polystyrene resin, polycarbonate resin, polyester resin, polyethylene resin, polypropylene resin, polyamide resin, polyurethane resin, acrylic-butadiene-styrene copolymer (ABS) resin, vinyl acetate resinSelected from.
[0026]
These resins can be used alone or in combination of two or more. Preferably, an acrylic resin is used. Furthermore, among acrylic resins, silicone-acrylic resins are preferably used. Such silicone-acrylic resins are commercially available products such as KP541, KP543, KP545 (manufactured by Shin-Etsu Chemical Co., Ltd.), Coponil 1815L (Nihon Gosei Co., Ltd.), and Cymac US- 413 (manufactured by Toa Gosei Co., Ltd.).
[0027]
  Acrylic resin, polystyrene resin, polycarbonate resin, polyester resin, polyethylene resin, polypropylene resin, polyamide resin, polyurethane resin, acrylic-butadiene-styrene copolymer (ABS) resin, vinyl acetate resinFatBy using it, the fixability of the fine particles can be improved and the durability as a water repellent treatment agent can be improved. Furthermore, among these resins, in particular, by using a silicone-acrylic resin, fine particles can be firmly fixed and durability can be improved without reducing the transparency of the water repellent agent.
[0028]
  In order to obtain the water repellent agent of the present invention, fine particles, a coupling agent, an acid, a solvent, andTreeFat may be blended as appropriate, but it is necessary that a coupling agent be blended at least in a state where fine particles are dispersed by ultrasonic waves or high-speed turbulent energy.
[0029]
That is, for example, if a coupling agent is blended before dispersion of the fine particles, and then the excess coupling agent is removed by drying or the like, then the fine particles are dispersed by ultrasonic or high-speed turbulent energy. The virgin surface is exposed, but the exposed virgin surface is not treated with the silane coupling agent. As a result, the surface of the fine particles not treated with the silane coupling agent is increased, and water repellency is expressed. Can not be. In addition, if the surface that is not treated with the silane coupling agent remains, for example, hydrogen bonds may be formed between the untreated surfaces over time, and may be re-aggregated in the dispersion liquid even though it is dispersed with great effort. is there.
[0030]
However, if a coupling agent is blended in a state where the fine particles are dispersed by ultrasonic waves or high-speed turbulent energy, the virgin surface exposed by pulverization is also treated by the coupling agent, so that the fine particles are well dispersed. And exhibiting excellent water repellency.
[0031]
  Such preparation is not particularly limited, but more specifically, for example, fine particles, coupling agents, acids, solvents andTreeThe fats are blended at the same time and dispersed by ultrasonic or high-speed turbulent energy, or, for example, the fine particles and the solvent are blended at the same time and dispersed by ultrasonic or high-speed turbulent energy, then the cup Ring agent, acid andTreeFat is blended into this dispersion.
[0032]
  The blending ratio of each component is relative to the resulting water repellent treatment agent., FineThe particles are 0.3 to 5% by weight, preferably 0.5 to 4% by weight, and the coupling agent is 0.00001 to 0.1% by weight when the fine particles have been subjected to hydrophobic treatment in advance, preferably Is 0.0001 to 0.05% by weight, and 0.2 to 4% by weight, preferably 0.5 to 2% by weight, and the acid is 0.00001 to 0.05% when the fine particles have not been subjected to hydrophobic treatment in advance. 0.1% by weight, preferably 0.0001 to 0.05% by weight, resin is 0.001 to 0.1% by weight, preferably 0.001 to 0.05% by weight, and the remaining amount is The solvent is appropriately selected so as to be a solvent.
[0033]
If the amount of fine particles is less than 0.3% by weight, the object to be treated may not be coated with fine particles and may not exhibit excellent water repellency. If the amount is more than 5% by weight, the object to be treated is excessive. For example, when the object to be processed is a mirror, the image projected on the surface of the mirror may be difficult to see due to the coating of the fine particles.
[0034]
If the coupling agent is less than 0.00001 wt% when the fine particles have been previously hydrophobized, or less than 0.2 wt% when the fine particles have not been previously hydrophobized, the surface of the fine particles In some cases, the amount of the coupling agent for the treatment is insufficient and sufficient water repellency cannot be imparted to the fine particles, and more than 0.1% by weight when the fine particles have been subjected to hydrophobic treatment in advance. Alternatively, if the fine particles are not subjected to a hydrophobic treatment in advance, if the amount is more than 4% by weight, an excessive free coupling agent that does not contribute to the surface treatment of the fine particles remains. For example, the object to be treated is a mirror. In some cases, when the mirror surface is treated, the OH groups on the mirror (glass) surface react with the free coupling agent. Coupling agent attached to the surface of the mirror, the surface of the mirror becomes weak water-repellent state. In such a case, when the surface of the mirror is reprocessed with the water repellent treatment agent, the water repellent treatment agent may not be uniformly applied.
[0035]
In the case of dispersing by ultrasonic waves, for example, using an ultrasonic disperser having a specification with an output of about 50 to 800 W, for example, 5 minutes to 24 hours, preferably 10 minutes to 8 hours may be mixed and dispersed. .
[0036]
In addition, when dispersing by high-speed turbulent energy, for example, as described in JP-A-11-29722, a high-speed turbulent energy mixing device is used to generate a generator having a hole of several hundred μm. The turbulent flow is generated by injecting and applying a high pressure, thereby mixing and dispersing.
[0037]
By dispersing with such ultrasonic waves or high-speed turbulent energy, it is possible to reduce the secondary average particle diameter and the half width of the frequency distribution of the obtained water repellent treatment agent.
[0038]
In addition, the water repellent treatment agent of the present invention is usually added in a range that does not impair excellent water repellency and transparency, for example, a viscosity modifier, an antioxidant, an ultraviolet absorber, a rust inhibitor, a fragrance, You may mix | blend additives, such as a coloring agent, suitably.
[0039]
And, the water repellent treatment agent of the present invention thus obtained has a secondary average particle size of 50 nm or less, preferably 10 to 30 nm, and more preferably the half width of the frequency distribution is 20 nm or less. Further, it is prepared as a dispersion of fine particles of 2 to 15 nm. When the secondary average particle diameter of the obtained water repellent treatment agent exceeds 50 nm, the transparency is lowered and the contact property with water is also lowered.
[0040]
The secondary average particle size is different from the above-mentioned primary average particle size, and is the average particle size of the aggregated state (apparent) of fine particles after dispersion. For example, as a photon correlation method (PCS), an apparatus It can be measured with a Zetasander series 3000HS manufactured by Sysmec Corporation.
[0041]
Further, when the half width of the frequency distribution of the obtained water repellent treatment agent exceeds 20 nm, for example, when the object to be treated is a mirror, a uniform film thickness is obtained when the surface of the mirror is treated. May not be possible and transparency may be reduced. In addition, the half value width of this dispersed particle size can also be measured by, for example, a photon correlation method (PCS) and a Zetasanser series 3000HS manufactured by Sysmec Co., Ltd. as with the secondary average particle size.
[0042]
The water repellent treatment agent of the present invention thus has a small secondary average particle diameter, and preferably has a small half width of the frequency distribution and a relatively uniform particle diameter. On the other hand, for example, a super water repellency with a contact angle of 140 ° or more, further 150 ° or more can be imparted, and for example, the light transmittance at a measurement wavelength of 600 nm is 70% or more, and further 80 % Or more, particularly 90% or more of sufficient transparency can be ensured.
[0043]
Therefore, the water-repellent treatment agent of the present invention is used outdoors where rainwater is applied, and is a member that requires excellent transparency (light transmittance of 70% or more) for safety, such as an automobile side mirror, on the road It can be suitably used as a water repellent treatment agent for treating the surface of a curved mirror or the like to prevent adhesion of rainwater.
[0044]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples and comparative examples.
[0045]
1) Preparation of Examples and Comparative Examples
Example 1
Aerosil R976S 2.0% by weight
CF_Three(CF₂)₇CH₂CH₂SiCH_Three(OC_ThreeH₇)₂   0.005% by weight
98% sulfuric acid 0.1% by weight
Vinylol S 0.05% by weight
Isopropyl alcohol 97.845% by weight
In the above composition, Aerosil R976S (manufactured by Nippon Aerosil Co., Ltd., primary average particle diameter 7 nm, surface hydrophobic treatment), CF_Three(CF₂)₇CH₂CH₂SiCH_Three(OC_ThreeH₇)₂, 98% sulfuric acid, vinylol S (vinyl acetate resin, Showa High Polymer Co., Ltd.) was blended in isopropyl alcohol, and this was mixed with an ultrasonic disperser (F-5 type, Nippon Seiki Seisakusho Co., Ltd., output 150 W). ) And mixed and dispersed for 30 minutes to obtain a water repellent treatment agent. The resulting water repellent agent had a secondary average particle size of 40 nm and a frequency distribution half width of 15 nm.
[0046]
Example 2
Aerosil R812 4.0% by weight
CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three     0.0002% by weight
99% acetic acid 0.0001% by weight
KP-545 0.1% by weight
Ethanol 95.8997 wt%
In the above composition, Aerosil R812 (manufactured by Nippon Aerosil Co., Ltd., primary average particle diameter 7 nm, surface hydrophobic treatment), CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three, 99% acetic acid, KP-545 (silicone-acrylic resin, manufactured by Shin-Etsu Chemical Co., Ltd.) was blended in ethanol, and this was mixed with an ultrasonic disperser (Nippon Seiki Seisakusho F-5, Using an output of 150 W), the mixture was dispersed for 1 hour to obtain a water repellent treatment agent. The resulting water repellent agent had a secondary average particle size of 30 nm and a frequency distribution half width of 12 nm.
[0047]
Example 3
Aerosil RY300 1.0% by weight
Isopropyl alcohol 25.0% by weight
Ethanol 63.917% by weight
Ethylene glycol 10.0% by weight
CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three     0.03% by weight
99% formic acid 0.05% by weight
KP-543 0.003% by weight
In the above composition, Aerosil RY300 (manufactured by Nippon Aerosil Co., Ltd., primary average particle size 7 nm, surface hydrophobic treatment) is blended in ethanol, isopropyl alcohol, and ethylene glycol, and this is mixed with an ultrasonic disperser (SMT). The mixture was dispersed for 40 minutes using a ULTRA SONIC HOMOGENIZER UH-600S manufactured by COMPANY. In this dispersion, CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three99% formic acid and KP-543 (silicone-acrylic resin, Shin-Etsu Chemical Co., Ltd.) were mixed and stirred well to obtain a water repellent. The resulting water repellent agent had a secondary average particle size of 20 nm and a half width of 8 nm.
[0048]
Example 4
Aerosil 380 0.5% by weight
Ethanol 30.0% by weight
Isopropyl alcohol 68.88% by weight
CF_Three(CF₂)_FourCH₂CH₂SiCH_Three(OC_ThreeH₇)₂  0.5% by weight
99% acetic acid 0.08% by weight
KP-543 0.01 wt%
Coponille 1815L 0.03% by weight
In the above composition, Aerosil 380 (manufactured by Nippon Aerosil Co., Ltd., primary average particle size 7 nm, no surface hydrophobic treatment) was blended in ethanol, and this was mixed with an ultrasonic disperser (Nippon Seiki Seisakusho F -5 type, output 150 W) and mixed and dispersed for 1 hour. To this dispersion, isopropyl alcohol, CF_Three(CF₂)_FourCH₂CH₂SiCH_Three(OC_ThreeH₇)₂, 99% acetic acid, KP-543 (silicone-acrylic resin, manufactured by Shin-Etsu Chemical Co., Ltd.), Coponil 1815L (silicone-acrylic resin, manufactured by Nihon Gosei Co., Ltd.) A water treatment agent was obtained. The resulting water repellent agent had a secondary average particle size of 35 nm and a half width of 14 nm.
[0049]
Example 5
Aerosil RY300 0.8% by weight
Ethanol 99.09 wt%
CF_Three(CF₂)_FourCH₂CH₂SiCH_Three(OC_ThreeH₇)₂    0.04% by weight
99% formic acid 0.06% by weight
Coponille 1815L 0.01 wt%
In the above composition, Aerosil RY300 (manufactured by Nippon Aerosil Co., Ltd., primary average particle size 7 nm, surface hydrophobic treatment) was blended in ethanol, and this was mixed with an ultrasonic disperser (Nihon Seiki Seisakusho F-5). And dispersion for 50 minutes. In this dispersion, CF_Three(CF₂)_FourCH₂CH₂SiCH_Three(OC_ThreeH₇)₂, 99% formic acid, Coponil 1815L (silicone-acrylic resin, manufactured by Nihon Gosei Co., Ltd.) and mixed well to obtain a water repellent. The resulting water repellent agent had a secondary average particle size of 38 nm and a half width of 19 nm.
[0050]
Comparative Example 1
Nipsil E-743 8.0 wt%
CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three     0.08% by weight
98% sulfuric acid 0.03% by weight
KP-545 0.1% by weight
Isopropyl alcohol 63.79% by weight
Ethylene glycol 28.0% by weight
In the above composition, Nipsil E-743 (manufactured by Nippon Silica Kogyo Co., Ltd., primary average particle size 70-80 nm, no surface hydrophobic treatment), CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three, 98% sulfuric acid, KP-545 (silicone-acrylic resin, Shin-Etsu Chemical Co., Ltd.) was blended in isopropyl alcohol and ethylene glycol, and this was mixed with an ultrasonic disperser (manufactured by SMT COMPANY, ULTRA SONIC HOMOGENIZER). (UH-600S, output 600 W) was mixed and dispersed for 50 minutes to obtain a water repellent treatment agent. The resulting water repellent agent had a secondary average particle size of 350 nm and a half width of 240 nm.
[0051]
Comparative Example 2
Aerosil RY300 0.8% by weight
Ethanol 99.13 wt%
KF96 500cs 1.0 wt%
99% formic acid 0.06% by weight
Coponille 1815L 0.01 wt%
In the above composition, Aerosil RY300 (manufactured by Nippon Aerosil Co., Ltd., primary average particle size 7 nm, surface hydrophobic treatment) was blended in ethanol, and this was mixed with an ultrasonic disperser (Nihon Seiki Seisakusho F-5). And dispersion for 50 minutes. To this dispersion, KF96 500cs (silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.), 99% formic acid, and Coponil 1815L were blended and stirred well to obtain a water repellent treatment agent. The resulting water repellent agent had a secondary average particle size of 38 nm and a half width of 19 nm.
[0052]
Comparative Example 3
Aerosil 50 2.0% by weight
CF_Three(CF₂)₂CH₂CH₂Si (OC_ThreeH₇)_Three     1.0% by weight
99% acetic acid 0.04% by weight
Cymac US-413 0.08% by weight
Isopropyl alcohol 81.88% by weight
Ethylene glycol 15.0% by weight
In the above composition, Aerosil 50 (manufactured by Nippon Aerosil Co., Ltd., primary average particle size 30 nm, no surface hydrophobic treatment), CF_Three(CF₂)₂CH₂CH₂Si (OC_ThreeH₇)_Three, 99% acetic acid, Cymac US-413 (silicone-acrylic resin Toa Gosei Co., Ltd.) was blended in isopropyl alcohol and ethylene glycol, and this was mixed with an ultrasonic disperser (Nippon Seiki Seisakusho F- 5 type, output 150 W) was mixed and dispersed for 50 minutes to obtain a water repellent treatment agent. The resulting water repellent treatment agent had a secondary average particle size of 68 nm and a half width of 70 nm.
[0053]
Comparative Example 4
Aerosil R976S 3.0% by weight
99% formic acid 0.09% by weight
KP-545 0.09 wt%
Ethanol 76.82% by weight
Isopropyl alcohol 20.0% by weight
In the above composition, Aerosil R-976S (manufactured by Nippon Aerosil Co., Ltd., primary average particle size 7 nm, surface hydrophobic treatment), 99% formic acid, KP-545 (silicone-acrylic resin Shin-Etsu Chemical Co., Ltd.) Was mixed in ethanol and isopropyl alcohol, and this was mixed and dispersed for 40 minutes using an ultrasonic disperser (F-5, manufactured by Nippon Seiki Seisakusho Co., Ltd., output 150 W) to obtain a water repellent treatment agent. . The resulting water repellent agent had a secondary average particle size of 55 nm and a half width of 30 nm.
[0054]
Comparative Example 5
Aerosil RY300 2.5% by weight
CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three         0.1% by weight
Isopropyl alcohol 97.25% by weight
99% acetic acid 0.09% by weight
Cymac US-413 0.06% by weight
In the above composition, Aerosil RY300 (manufactured by Nippon Aerosil Co., Ltd., primary average particle size 7 nm, surface hydrophobic treatment), CF_Three(CF₂)_FiveCH₂CH₂Si (OC₂H_Five)_Three99% acetic acid, Cymac US-413 (silicone-acrylic resin Toa Gosei Co., Ltd.) was blended in isopropyl alcohol, and meteor mill SH-3 type (FRITSCH, rotation speed 740 min)^-1) And mixed and dispersed for 35 minutes to obtain a water repellent treatment agent. The resulting water repellent agent had a secondary average particle size of 525 nm and a half width of 320 nm.
[0055]
2) Evaluation
Contact angle test
Each Example and each Comparative Example were uniformly applied with a finger spray to a vertically arranged 15 cm × 15 cm mirror and dried for 30 minutes. Thereafter, the contact angle was measured using a contact angle meter (CA-S150 type manufactured by Kyowa Interface Chemical Co., Ltd.) to obtain an initial contact angle.
[0056]
The mirror applied with each example and each comparative example was tilted 45 degrees and 0.05 g of water droplets were dropped from a height of 10 cm to the same place, and the contact angle after dropping 160 drops was determined as the durable contact angle. . The results are shown in Table 1. The evaluation in Table 1 was as follows.
[0057]
A contact angle of 150 degrees or more ◎
A contact angle of 140 degrees or more and less than 150 degrees ○
A contact angle of 130 degrees or more and less than 140 degrees △
Contact angle less than 130 degrees ×
Transparency test
Each Example and each Comparative Example were uniformly applied with a finger spray to a vertically arranged 15 cm × 15 cm mirror and dried for 30 minutes. Thereafter, the transparency of the mirror was examined. The results are shown in Table 1. The evaluation in Table 1 was as follows.
[0058]
The coated surface does not become white and the image can be seen without change from the uncoated part.
The coated surface is slightly white and the image is slightly less visible than the uncoated portion.
The coated surface is quite white and the image is much less visible compared to the uncoated area.
The coated surface is clearly white and the image is not visible ×
Stability test
Each example and each comparative example were allowed to stand at room temperature for 1 hour and allowed to stand at room temperature for 1 month, and then the transmittance at a wavelength of 600 nm was measured for each using UV-2400PC manufactured by Shimadzu Corporation. Stability was examined. The results are shown in Table 1. The evaluation in Table 1 was as follows.
[0059]
Transmission 90% or more ◎
Transmittance 80% or more and less than 90% ○
Transmittance 70% or more and less than 80%
Transmittance less than 70% ×
[0060]
[Table 1]

【The invention's effect】
According to the water repellent treatment agent of the present invention, super water repellency can be imparted to the object to be treated, and sufficient transparency can be ensured. Therefore, the water-repellent treatment agent of the present invention is used outdoors where rainwater is applied, and is a member that requires excellent transparency (light transmittance of 70% or more) for safety, such as an automobile side mirror, on the road It can be suitably used as a water repellent treatment agent for treating the surface of a curved mirror or the like to prevent adhesion of rainwater.

Claims (4)

Containing inorganic or organic fine particles having a primary average particle diameter of less than 10 nm, a coupling agent, an acid , a resin, and a solvent;
A water repellent treatment agent that is blended with a coupling agent at least in a state where inorganic or organic fine particles are dispersed by ultrasonic waves or high-speed turbulent energy, and is obtained as a secondary average particle size of 50 nm or less. ,
The resin is selected from the group consisting of acrylic resin, polystyrene resin, polycarbonate resin, polyester resin, polyethylene resin, polypropylene resin, polyamide resin, polyurethane resin, acrylic-butadiene-styrene copolymer (ABS) resin, and vinyl acetate resin. At least one resin,
The coupling agent is a fluoroalkylsilane compound represented by the general formula (1),
YRSiX ₃ (1)
Wherein Y is a fluorinated alkyl group having 2 to 12 carbon atoms, R is an alkylene group having 2 to 4 carbon atoms, X is the same or different, and is an alkoxy group having 1 to 4 carbon atoms or a chlorine atom Or any one of alkyl groups having 1 to 4 carbon atoms, except that X is an alkyl group.
The amount of the inorganic or organic fine particles is 0.3 to 5% by weight in the water repellent agent,
The amount of the coupling agent is 0.00001 to 0.1% by weight when the inorganic or organic fine particles are previously subjected to hydrophobic treatment in the water repellent treatment agent, and the inorganic or organic fine particles are When the hydrophobic treatment is not performed, it is 0.2 to 4% by weight,
The compounding amount of the resin is 0.001 to 0.1% by weight in the water repellent agent,
A water repellent treatment agent characterized by being used for surface treatment of a member that requires a light transmittance of 70% or more at a wavelength of 600 nm . The water repellent agent according to claim 1, wherein the resin is a silicone-acrylic resin. The water repellent treatment agent according to claim 1 or 2, wherein the compounding amount of the acid is 0.00001 to 0.1% by weight in the water repellent treatment agent. The water repellent treatment agent according to any one of claims 1 to 3, which is used for surface treatment of a mirror.