JP2002080830A - Hydrophilic member and its production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrophilic member which maintains a sufficient film hardness and durability and is less prone to fog and less prone to allow a water droplet and dirt to adhere, and a method for producing the same. SOLUTION: The hydrophilic member has at least a substrate 1 and a hydrophilic film to be formed on the substrate as the utmost outer layer, and the above hydrophilic film comprises at least film-forming elements of alumina particles 2 and an amorphous silica 3, and part of the alumina particles is exposed from its surface and, simultaneously, the surface roughness in any 5 μm square of the above hydrophilic film, measured by an atomic force microscope, is 5-35 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a member having a hydrophilic surface, more specifically, an antifogging property and an antifouling property are required.
For example, the present invention relates to a hydrophilic member such as a glass, a mirror, a reflection plate, and a protection plate, which is particularly suitable as a bathroom mirror, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Transparent members such as glass and plastic, reflecting members such as mirrors and metal plates, and other members having a design on the surface, may cause moisture in the air when the surface temperature falls below the dew point temperature. Are easily aggregated on the surface and fogging is likely to occur. Also, if rainwater or splashes adhere to the surfaces of these members, they tend to adhere as water droplets rather than as water films. As described above, if fogging or water droplets are present on the surface of the member, the original function of the member may not be exhibited, or the appearance and design of the member may be reduced due to light scattering.

The following techniques are known as techniques for making the surface of a substrate hydrophilic in order to eliminate such fogging and light scattering. In JP-A-9-278431, a surface treatment material comprising phosphoric acid or a salt thereof, a soluble aluminum compound, a water-soluble silicate, a surfactant and a solvent is applied to the surface of a base material, A method for forming irregularities on the surface by performing a heat treatment on the surface is disclosed. Japanese Patent Application Laid-Open No. 11-100234 discloses that
A film made of metal oxide particles and a metal oxide having a particle diameter of 0 nm is formed, and the arithmetic average roughness (Ra) is 1.5 to 80.
There is disclosed a method for forming unevenness having an average unevenness interval (Sm) of 4 to 300 nm in nm.

[0004]

SUMMARY OF THE INVENTION The present inventors have recently proposed:
Without reducing the film hardness and durability, the surface condition of the hydrophilic member is controlled to effectively prevent the adhesion of dirt, and the hydrophilicity is maintained to a high degree to exhibit excellent anti-fog properties. It has been found that a conductive member can be obtained. Accordingly, an object of the present invention is to provide a hydrophilic member that is not easily fogged and hardly adheres to water droplets and dirt while maintaining sufficient film hardness and durability.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a hydrophilic member having at least a substrate and a hydrophilic film formed as an outermost layer on the substrate. Wherein the hydrophilic coating comprises at least alumina film and a film-forming element of amorphous silica, a part of the alumina particles are exposed from the surface, and the atomic force of the hydrophilic coating The surface roughness in an arbitrary 5 μm square measured by a microscope is 5 to 35 nm.

The function of the above hydrophilic member is considered as follows. It is generally said that the glass surface exhibits high hydrophilicity, but it cannot be said that ordinary glass sheets and mirrors have high wettability to water. This is presumably because contaminants adhered to the surface and the hydrophilicity of the surface was impaired.
In the hydrophilic member of the present invention, by exposing the alumina particles on the surface, the adsorbed water layer on the surface of the alumina particles is stably present for a long period of time. In addition, the film-forming element made of amorphous silica in the present invention can be formed using an organometallic compound of silicon and / or a hydrolyzate thereof. The amorphous silica body formed by such a method has a hydrophilic silanol group on the surface,
It is generally known that there are innumerable fine pores, and it is considered that the hydrophilicity is enhanced by firmly holding the adsorbed water. With these alumina and amorphous silica,
While maintaining hydrophilicity, the conductivity can be prevented from being attracted by increasing the electrical conductivity, and the adsorbed water layer acts as a protective layer on the surface to adhere the contaminants to the hydrophilic coating surface. It is thought that can be prevented.

[0007] Among substances generated and adhered in the bathroom, cationic surfactants are mentioned as those which particularly affect the hydrophilic surface. The cationic surfactant is contained as a main component of the rinse, and has a property of strongly adsorbing to a negatively charged hydrophilic surface such as a glass surface and making the surface lipophilic. Therefore, it is used to protect metal surfaces and various surfaces in addition to hair, and when rinsing adheres to a hydrophilic surface, the hydrophilicity is immediately lost and water repellency is exhibited. On such surfaces, sebum dirt, secretions of the human body, and insoluble fatty acid metal salts (metal soaps, typically calcium oleate) formed by the reaction of proteins and soaps with metal ions such as calcium in water are hydrophobic. It is considered that adsorption or adhesion occurs due to the temporary bonding, which becomes dirty and accumulates. Alumina particles are solid acidic substances, and when they come into contact with a nearly neutral liquid such as tap water, the surface has a positive charge, so that adsorption of a rinse component can be prevented. Therefore, when the alumina is exposed from the surface and coated with amorphous silica as in the hydrophilic member of the present invention, it is possible to prevent water repellency due to adhesion of a rinse component and maintain hydrophilicity for a long time. it is conceivable that.

[0008] The present invention also relates to a surface roughness in an arbitrary 5 µm square measured by an atomic force microscope of 5 to 35 n.
When m, a water film is quickly formed under wet conditions. (Here, “surface roughness” is JIS-B06
The center line average roughness (Ra), which is a parameter defined by J. 01 (1994), can be obtained by plane-expanding data obtained by an atomic force microscope. For example, when a mirror, which is a hydrophilic member according to the present invention, is disposed in a bathroom, if steam or splashes adhere to the surface, the water with the hydrophilic coating on the surface continues to be retained as a water film. In this state, even if the surface temperature is equal to or lower than the dew point temperature, if the water vapor is in contact with the surface, or if water droplets are attached due to the attachment of splashes, the water film on the hydrophilic coating is maintained. Furthermore, since the uniform water film makes it difficult for the dirt substance to directly contact the surface of the base material, dirt is hardly adhered. That is, the hydrophilic member according to the present invention can also exhibit excellent antifouling properties. For example, in a bathroom environment, an effect of preventing adhesion of a metal soap or a rinsing component is exhibited, and in a building material such as an outer wall, an effect of preventing adhesion of urban dust outside is exhibited.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In a first preferred embodiment of the hydrophilic member according to the present invention, as shown in a schematic sectional view of FIG. 1, a hydrophilic coating formed as an outermost layer on a substrate 1 comprises:
At least an alumina particle 2 and a film-forming element 3 made of amorphous silica. At this time, the particle size is 3 nm.
In the case of the following alumina particles, the exposure of the alumina particles on the surface is insufficient, and when the particle size is 100 nm or more, it is not preferable because of cloudiness and a decrease in film strength. The shape of the alumina particles may be spherical, rectangular, flat, feathered, chain-like, or the like, but spherical or rectangular is preferred for appropriately controlling the surface roughness.

As the coating film forming material for fixing the alumina particles, a metal oxide which forms chemically adsorbed water on the surface and easily exhibits hydrophilicity is preferable. Alumina particles are
In order to disperse easily as a coating solution because it is a solid acid and is stably dispersed in an acidic state, it is necessary to carry out dehydration condensation polymerization based on a hydrolyzable organometallic compound of silicon and / or a hydrolyzate thereof. Amorphous silica formed is preferred. Such an amorphous silica precursor can easily coexist with hydrochloric acid, nitric acid, sulfuric acid, acetic acid, citric acid, sulfonic acid, maleic acid, etc., which are generally used as a hydrolysis catalyst. Further, as a precursor of amorphous silica,
An organometallic compound of silicon and / or a hydrolyzate thereof can be suitably used. For example, in the case of an alkoxide, methoxide, ethoxide, propoxide, butoxide and the like are used. It may be a polymerized one. In particular,
Tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, diethoxydimethoxysilane, and the like can be suitably used.Other than this, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, Methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, ethyltributoxysilane, silanol, tetrachlorosilane, tetrabromosilane, and the like can also be used. The use of an amorphous silica precursor prepared from a commercially available hydrolyzable silane derivative makes it possible to easily form the hydrophilic coating of the present invention. According to the second preferred embodiment of the present invention, as shown in FIG. 2, when a line segment is set only in a portion having a raised portion on the surface of the hydrophilic coating and not including the raised portion ( The line segment A), Rz (ten-point average roughness) and Sm (average interval of unevenness) indicated by the cross-sectional curve of the line segment are 10 nm ≦ Rz ≦ 40 nm and 10 nm ≦ Sm ≦ 300 nm, respectively, and When a line segment is set so as to pass through a portion (line segment B), Rz (ten-point average roughness) and Sm (average interval of unevenness) indicated by a cross-sectional curve of the line segment are respectively 40 nm ≦ R.
z ≦ 200 nm and 300 nm ≦ Sm ≦ 1500 nm
It is.

Here, in the present invention, "ten point average roughness"
(Rz) ”is defined in JIS-B0601 (1994).
Parameters defined by the
Set a line segment and use the cross-sectional curve at that line segment,
5th from the highest peak in a 5μm × 5μm square
Absolute value (R₁, R_Three, R_Five, R₇,
R ₉) And the lowest to fifth valley bottom
Absolute value of the altitude (R_Two, R_Four, R₆, R₈, R_Ten) Average
And the value obtained by the following equation. What
In the present invention, the length of the set line segment is not particularly defined.
However, considering the variation of Rz, take as long as possible
Set. The above JIS standards are Japanese Industrial Standards (East Japan)
4-1-24 Akasaka, Minato-ku, Kyoto)
It is readily available.

[0012]

[Formula 1]

Further, in the present invention, the “average interval of unevenness (Sm)” is a parameter defined by ISO, and a roughness curve having an evaluation length N times the sampling length equal to the cutoff value is expressed by N aliquoted, mean spacing S of spacing irregularities in each section (width Sm _i phases adjacent pair of peaks and valleys)
m ′ is obtained by the following equation. Then, Sm is obtained as an arithmetic average value of the N Sm's.

[0014]

[Formula 2]

The ten-point average roughness (Rz) and the average interval of unevenness (Sm) can be determined by measuring the surface shape of 5 μm × 5 μm at an arbitrary position of the coating using an atomic force microscope. .

According to a second preferred embodiment of the present invention, the hydrophilic metal oxide particles are made to have a particle size of 3 to 40 nm (preferably 1 to 40 nm).
A first hydrophilic metal oxide particle having a mode of the particle diameter at 0 to 30 nm, and 40 to 300 nm (preferably 40 to 300 nm).
(100 nm) and second hydrophilic metal oxide particles having a mode value of the particle diameter. That is,
As the hydrophilic metal oxide particles, those having the above two particle diameter ranges are used in combination. As a result, the above-described conditions of Rz and Sm can be realized relatively easily.

As shown in the schematic cross-sectional view of FIG. 2, a hydrophilic metal oxide particle 4 having a first particle size, a hydrophilic metal oxide particle 5 having a second particle size, and a hydrophilic metal oxide particle 5 having a second particle size. The above-described Rz and Sm are realized by further forming the hydrophilic film of the present invention on the formed concavo-convex structure forming film by the non-crystalline inorganic amorphous material 6. Thereby, large and small irregularities are formed on the surface of the base material 1 on the surface of the hydrophilic member. It is considered that these large and small irregularities increase the surface area of the hydrophilic coating and maximize the hydrophilicity of the surface of the hydrophilic coating. That is, it is considered that a water film can be easily formed on the surface of the hydrophilic member, and a sufficient amount of the water film can be maintained uniformly. It is thought that the spread of the film is promoted.

According to a preferred embodiment of the present invention, preferred examples of the hydrophilic metal oxide particles include SiO ₂ , Al
₂ O ₃ , photocatalytic TiO ₃ , ZrO ₂ and conductive SnO ₂
And one or more selected from the group consisting of: SiO ₂ is a colloidal silica, Al ₂
O ₃ is easily available as an alumina sol, ZrO ₂ as a zirconia sol, and SnO ₂ as a tin oxide sol, and exhibits a high degree of hydrophilicity. Among them, particularly, colloidal silica exhibits a high degree of hydrophilicity, and various particle sizes are easily available, and the surface structure is easily controlled. Moreover, since the alumina sol firmly holds the adsorbed water layer on the surface, it is possible to maintain a high degree of hydrophilicity.

Photocatalytic TiO ₂ has the effect of generating active oxygen species from water molecules in response to excitation by irradiation with light having energy equal to or greater than its band gap energy, thereby oxidizing and decomposing organic substances, and directly decomposing organic substances. Demonstrate the effect to make. Therefore, in mirrors such as bathrooms, surfactants and alcohol contained in shampoos and rinses that cause adhesion and reduce hydrophilicity, or metal soap,
For sebum and mirrors used outdoors,
Substances that inhibit hydrophilicity, such as exhaust gas components that are included in the atmosphere and inhibit the hydrophilicity of the surface and lipophilic components such as tire chips, can be decomposed and removed. In addition, the photocatalytic metal oxide particles themselves have a superhydrophilic surface to enhance the hydrophilicity of the coating surface and exhibit an antifogging effect, and an antifouling effect by making it easy for lipophilic soil to flow down by rainwater or showers etc. Can be demonstrated. In order to utilize such photocatalytic properties, it is desirable that at least a part of the particles is crystallized in an anatase type or a brookite type.

The conductive SnO2 can enhance the conductivity and suppress the adhesion of dirt. In addition, even if it is other than the above, it is easy to exhibit hydrophilicity as long as the particles can form an oxide on at least the surface, and for example, particles of nitride, boride, carbide and the like may be used.

The shape of these hydrophilic metal oxide particles can be various shapes such as spherical, rectangular, flat, feathered, and chain-like, and spherical or rectangular due to the ease of forming the uneven structure. Is preferred.

According to a preferred embodiment of the present invention, the hydrophilic inorganic amorphous substance is selected from the group consisting of amorphous silica, alkali silicate, alkali borosilicate, alkali zirconate and alkali phosphates. One comprising at least one selected from the group consisting of salts is exemplified. These substances easily form a chemically adsorbed water layer due to the presence of water, and can exhibit a high degree of long-term hydrophilicity. Among these, an alkali silicate is preferable, and more preferably, at least one of sodium silicate, potassium silicate, lithium silicate, and ammonium silicate is used. Generally, it is considered that the adhesiveness is stronger in the order of sodium silicate and potassium silicate, and the water resistance is stronger in the order of ammonium silicate and lithium silicate. However, it is more preferable to include lithium silicate in consideration of the film properties, film hardness, water resistance, and the like.

According to a preferred embodiment of the present invention, the coating of the hydrophilic member according to the present invention may contain boric acid and / or a boric acid compound. Thereby, the water resistance and chemical durability of the coating can be improved. Preferred examples of boric acid or boric acid compound include orthoboric acid, metaboric acid, tetraboric acid, zinc borate, potassium borate, sodium borate, barium borate, magnesium borate, lithium borate, borate ester and the like. Is mentioned.

According to a preferred embodiment of the present invention, the coating of the hydrophilic member according to the present invention may contain phosphoric acid and / or a phosphoric acid compound. Thereby, the curing of the film can be promoted, and the durability of the film can be improved. Preferred examples of phosphoric acid or a phosphoric acid compound include:
Phosphoric anhydride, metaphosphoric acid, pyrophosphoric acid, orthophosphoric acid,
Triphosphate, tetraphosphate, zinc phosphate, zinc hydrogen phosphate, aluminum phosphate, aluminum hydrogen phosphate, ammonium phosphate, ammonium hydrogen phosphate, ammonium sodium phosphate, potassium phosphate, potassium hydrogen phosphate, Examples thereof include calcium phosphate, calcium hydrogen phosphate, sodium phosphate, lithium hydrogen phosphate, and phosphate esters.

According to a preferred embodiment of the present invention, the coating of the hydrophilic member of the present invention may contain a precursor of a substance which becomes ZrO ₂ by heat treatment. Thereby, Zr is taken into the SiO ₂ structure in the alkali silicate,
Chemical durability can be improved. Preferred examples of the precursor of the substance that becomes ZrO ₂ by heat treatment include:
Zirconium chloride oxide, zirconium oxychloride, zirconium chloride, zirconium nitrate, zirconium acetylacetonate, zirconium butoxide, zirconium propoxide and the like.

According to a preferred embodiment of the present invention, the zeta potential of the surface of the hydrophilic film at pH = 7 is -40 to 40 m
V, more preferably -30 to 30 mV. By controlling the zeta potential to a range close to 0 in this manner, the adhesion of charged dirt is effectively prevented. For example, a cationic surfactant contained as a main component of a rinse generated and adhered in a bathroom, and an anionic surfactant contained in a shampoo, by controlling the zeta potential, the adhesion is suppressed, and the hydrophilicity is not reduced. It is possible to prevent the development of water repellency and maintain the antifogging property for a longer period of time. More preferably, the zeta potential is -25 to 0 mV. As a result, the adhesion of negatively charged dirt such as silica or clay mineral can be effectively prevented, and thus the hydrophilic member according to the present invention is used outdoors where it is exposed to atmospheric dust and car exhaust gas. This is advantageous.

According to a preferred embodiment of the present invention, the static contact angle of water of the hydrophilic coating is 35 degrees or less. This allows
When water droplets adhere, a water film can be efficiently formed, and as a result, the anti-fogging property can be improved. Also,
It is more preferable to set the static contact angle of water of the hydrophilic film to 20 degrees or less, since a rapid water film can be formed.
In addition, with respect to dirt having relatively low polarity such as oily dirt generated from exhaust gas or the like, dirt can be easily removed with rainwater or the like if the contact angle is 35 degrees or less, and more preferably. 20 degrees or less.

In the present invention, the substrate means an article expected to have an antifogging effect, an antifouling effect, and a hydrophilic effect.
It may be made of a metal material, an organic material, or a composite thereof. Preferable examples of the substrate include articles requiring antifogging and antifouling properties, such as tiles, sanitary ware, tableware, glass, mirrors, reflectors, protective plates, protective films, ceramics, calcium silicate plates, cement, and wood. , Resins, metals, building materials such as ceramics, daily necessities and the like. More preferred examples include glass and glass lids, which are transparent members, mirrors and reflectors that require a light reflecting function, and protective plates, protective films and films that require light transmission.

More specifically, the substrate is used as a mirror such as a rearview mirror for a vehicle, a side mirror for a vehicle, a mirror for a bathroom, a mirror for a toilet, a dental mirror, a road mirror; a spectacle lens, an optical lens, and a camera. Lenses, lenses for endoscopes, lenses for lighting, lenses for semiconductors, lenses for copiers; prisms; windows of buildings and towers; automobiles, railway vehicles, aircraft, ships, submersibles, snowmobiles, ropes Way glass, amusement park gondola, window glass for vehicles like spaceships; cars, railcars, aircraft, ships, submarines, snowmobiles, snowmobiles, motorcycles, ropeway gondola, amusement park gondola, space Windshield for ship-like vehicles; protective goggles, sports goggles, protective mask shield, sports mask shield, helmet shield, frozen Glass goods display case; and the cover glass of the measuring equipment. In particular, a bathroom member is preferable as an easily fogging use, and a bathroom mirror is most preferable.

The preferred means for producing the hydrophilic member according to the first aspect of the present invention include a step of preparing a substrate, an alumina particle and an organometallic compound of hydrolyzable silicon which is a precursor of amorphous silica. And / or a step of preparing a coating agent comprising at least a hydrolyzate thereof, a step of coating the substrate with the coating agent to form a coating, and, if necessary, at least a coating surface of the coating. This can be achieved through a heat treatment step.

Further, as a preferable means for producing the hydrophilic member in the second aspect of the present invention, a step of preparing a substrate, which comprises at least hydrophilic metal oxide particles and a hydrophilic inorganic amorphous substance. Preparing a first coating agent, coating the substrate with a first coating agent, forming a first coating, if necessary, heat treating at least the coated surface of the first coating. Providing a second coating agent comprising at least alumina particles and an organometallic compound of hydrolyzable silicon which is a precursor of amorphous silica and / or a hydrolyzate thereof; Coating the coating with a second coating agent, forming a second coating, if necessary, heat-treating at least the coated surface of the second coating, Possible it is.

In the second means, the weight ratio of the amount of SiO ₂ of the hydrophilic inorganic amorphous substance to the hydrophilic metal oxide particles is in the range of 10: 1 to 1: 4, and When the weight ratio between the amount of one hydrophilic metal oxide particle and the amount of the second hydrophilic metal oxide particle is 40: 1 to 1: 4, an uneven structure having an appropriate shape can be formed on the surface. .

Further, in the method for producing a hydrophilic member according to the first and second aspects, the ratio of the silica solid content of the alumina particles to the precursor of the amorphous silica may be 3: 7 to 19: 1. desirable. When the ratio is less than 3: 7, the hydrophilic property cannot be sufficiently exhibited,
When the amount of alumina is larger than 19: 1, the film strength cannot be sufficiently exhibited.

The method for applying the coating agent is not particularly limited, and examples thereof include spray coating, flow coating, spin coating, dip coating, and roll coating. Although the optimal mixture concentration differs depending on these application methods, after application,
Since the film is formed by drying, it is considered that there is no influence on the uneven shape of the hydrophilic film unless the ratio of each component is changed.

In a preferred embodiment of the present invention, the heat treatment brings the surface temperature of the coated surface to 80 to 500 ° C. If the temperature is lower than 80 ° C., the polymerization of the film-forming element is difficult to proceed sufficiently,
Above is not preferable because hydrophilicity is reduced.

[0036]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

Example 1 First, alumina particles were prepared. When this was observed with an electron microscope, the particle size was about 60 to 90 nm. 1 g of the alumina particles was added to a mixed solution of 5 g of 1N hydrochloric acid and 94 g of distilled water, and dispersed by ultrasonic waves to prepare a 1% alumina dispersion (solution A). Next, tetraethoxysilane (hereinafter referred to as TEOS: molecular formula Si (OC ₂ H ₅ ) ₄ )
g, 37.6 g of ethanol (molecular formula C ₂ H ₅ OH), 23.5 g of water, and 0.3 g of hydrochloric acid were prepared, and the mixture was stirred and sufficiently hydrolyzed TEOS to form a precursor of amorphous silica. As a result, a solution (solution B) of about 8.35% in terms of SiO2 component was obtained. Next, coating solution 1 was prepared by mixing 15 g of solution A, 4.2 g of solution B, 50 g of ethanol, and 30.8 g of distilled water. At this time, the total solid concentration was 0.5%, and Al2O3: SiO2 = 3: 7. next,
A coating liquid 2 was prepared by mixing 10 g of the liquid A, 4.8 g of the liquid B, 50 g of ethanol, and 35.2 g of distilled water. At this time, the total solid concentration was 0.5%, and Al2O3: S
iO2 = 2: 8. Next, 30 g of the solution A and alkali silicate (SLN73 (components: SiO ₂ , Na ₂ O, Li ₂
O, B ₂ O ₃ ), manufactured by Nippon Chemical Industry Co., Ltd., SiO2 2
(3.5%) 0.9 g, ethanol 5 g, distilled water 64.1
g was mixed to prepare a coating liquid 3. At this time, the total solid content concentration was 0.5%, and Al2O3: SiO2 =
6: 4. Next, 30 g of the solution A and an alkali silicate (SLN73 (components: SiO ₂ , Na ₂ O, Li ₂ O, B ₂
O ₃ ), manufactured by Nippon Chemical Industry Co., Ltd., SiO 2 fraction 23.5
%), 5 g of ethanol and 68.9 g of distilled water were mixed to prepare a coating liquid 4. At this time, the total solid concentration was 0.5%, and Al2O3: SiO2 = 5: 5.
It is. A 5 mm-thick silver-plated mirror cut into a 10 cm square was prepared as a substrate, and used as a # 1 sample. This is polished and washed with cerium oxide, and then coated with the above coating liquids 1, 2,
3 and 4 are applied one by one by spin coating, and then heat-treated at 150 ° C. for 30 minutes with a hot air drier,
Samples # 2, # 3, # 4, and # 5 were obtained. At this time, the contact angle of water of the # 2 sample was 19 degrees. Next,
5 hair rinses (Super Mildrinse, Shiseido)
% Solution was prepared, and samples # 1 to # 5 were sufficiently immersed and washed with running water.
The # 5 sample was water-repellent, and the # 2 and # 4 samples formed a water film. From the above, alumina particles: amorphous silica exhibit hydrophilicity in a region where the amount of alumina particles is larger than 3: 7, and in the case of a coating film formed of alumina particles and alkali silicate, alumina particles: alkali silicate ( It is considered that hydrophilicity can be maintained in a region where SiO2) is larger than 5: 5 and alumina particles are more.

Example 2 First, a glass mirror having a thickness of 5 mm was cut into a 10 cm square as a substrate. Next, as a hydrophilic inorganic amorphous substance, lithium silicate (lithium silicate 35 (Nissan Chemical Industries, Ltd.)
)), And silica particles (Snowtex ZL, particle size 7) as second hydrophilic metal oxide particles.
A solution prepared by dispersing 0 to 100 nm (manufactured by Nissan Chemical Industries, Ltd.) in ion-exchanged water so as to have a solid content of 0.05% is prepared, and spin-coated on the prepared base material which is polished and washed with cerium oxide. To coat the lower layer. This was mixed with 30 g of solution A, 2.4 g of solution B, 50 g of ethanol, and 17.6 g of distilled water used in Example 1 to prepare a coating solution (total solid content concentration was 0.5%, Al 2 O 3: Si).
O2 = 5: 5). This coating solution is applied as a top layer by spin coating, and further at 150 ° C. for 30 minutes.
After a heat treatment for 5 minutes, a # 6 sample was obtained. The surface shapes of the # 1 and # 6 samples used in Example 1 were measured. First, using a scanning probe microscope (manufactured by Shimadzu Corporation, Model SPM-9500), the shape of an arbitrary 5 μm square area on the surface of the hydrophilic coating of the test sample was measured, and the surface roughness was calculated. The sample was 0.3 nm and the # 6 sample was 19.3 nm. Next, as shown in FIG. 1 using the measured shape, a portion of the surface of the hydrophilic coating of the test specimen which does not pass through the metal oxide particles having a large particle diameter exposed to the surface in an arbitrary 5 μm square region is shown. Set the minutes, Rz and S
m was calculated (these are referred to as Rz1 and Sm1).
In addition, a line segment was set in a portion passing through the metal oxide particles having a large particle size, and Rz and Sm were calculated (these values are Rz2 and Sm2). The # 1 sample had Rz 0.08 nm and Sm 0 nm, while the # 6 sample had Rz122 nm, Sm1 236 nm, Rz2 46 nm, and Sm2 356 nm. When these # 1 and # 6 samples were placed in a bathroom and showered, the # 1 sample immediately repelled water, whereas the # 6 sample formed a water film. The hot water was discharged from the shower as it was and the door was kept closed. As a result, the # 1 sample was fogged.
The sample kept the water film even after 10 minutes, and there was no fogging. When the respective water contact angles were measured, the # 1 sample was 45 degrees, while the # 6 sample was 17 degrees.

Example 3 Samples # 1 and # 6 used in Example 2 were immersed in a diluted rinse solution and washed with running water in the same manner as in Example 1. After this is sufficiently dried in a dryer at 60 ° C., water is sprayed thereon, and then
The operation of drying with a dryer at ℃ was repeated four times. When the # 1 sample and the # 6 sample were taken out of the dryer and observed, the surface of the # 1 sample was found to have a large amount of circular spots that seemed to be scales, whereas the # 6 sample was hardly observed. .

[0040]

According to the present invention, it is possible to provide a hydrophilic member which is hard to be fogged and to which water droplets and dirt are hardly attached while maintaining sufficient film hardness and durability.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a cross section of a hydrophilic member according to a first embodiment of the present invention. 1: Base material 2: Alumina particles 3: Film forming element using amorphous silica

FIG. 2 is a conceptual diagram showing a cross section of a hydrophilic member according to a second embodiment of the present invention. 1: Base material 2: Alumina particles 3: Film forming element made of amorphous silica 4: Hydrophilic metal oxide particles composed of a first particle size 5: Hydrophilic metal oxide composed of a second particle size Particles 6: hydrophilic inorganic amorphous material

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C03C 17/25 C03C 17/25 A 4J038 C09D 1/02 C09D 1/02 5/00 5/00 Z 183/02 183 / 02 // C04B 41/61 C04B 41/61 41/80 41/80 A 41/81 41/81 Z 41/84 41/84 A 41/85 41/85 Z 41/87 41/87 C Z 41/89 41/89 C (72) Inventor Takayuki Kato 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka F-term (reference) 4D075 CA02 CA34 CA37 CA39 DA06 DB12 DB13 DB14 DB31 DC02 DC38 EC02 EC03 EC24 EC53 4F100 AA17C AA19B AA20B AA21C AA27C AA28C AA33C AB01A AD00A AD01A AE00A AE01A AE09A AG00A AK01A AP00A AR00B AT00A BA02 BA03 BA07 BA10A BA10B BA10C BA13 CC00B CC00C DD07B DD07C DE01B EH461 EH462 EJ422 GB08 JA12C JB05B JB05C JL06 JL07 JM02B JM02C YY00B YY00C 4G028 BA01 4G059 EA01 EA05 EB07 EB09 4H020 AA01 AB02 4J038 AA011 DL031 DL061 GA16 HA211 HA216 HA246 HA416 HA441 HA446 HA456 HA476 JC32 KA08 KA12 KA20 MA14 NA05 NA 06 NA20 PB02 PB05 PC02 PC03 PC04 PC06 PC08

Claims (25)

[Claims] 1. A hydrophilic member comprising at least a substrate and a hydrophilic film formed as an outermost layer on the substrate, wherein the hydrophilic film is made of alumina particles and amorphous silica. At least part of the alumina particles are exposed from the surface, and the surface roughness of the hydrophilic film in an arbitrary 5 μm square measured by an atomic force microscope is 5 to 35 nm. A hydrophilic member, characterized in that: 2. The particle size of the alumina particles is 3 to 100 n.
The hydrophilic member according to claim 1, wherein m is m. 3. The hydrophilic film is further coated on a concavo-convex structure forming film containing at least hydrophilic metal oxide particles and a hydrophilic inorganic amorphous material, and the surface of the hydrophilic film is coated with the hydrophilic film. When a line segment is set only in a portion having a protruding portion and not including the protruding portion, Rz (ten-point average roughness) and Sm (average interval of unevenness) indicated by a cross-sectional curve in the line segment are as follows. , 10n each
m ≦ Rz ≦ 40 nm and 10 nm ≦ Sm ≦ 300 nm
When a line segment is set so as to pass through the raised portion, Rz (ten-point average roughness) and Sm (average interval of unevenness) indicated by a cross-sectional curve in the line segment are respectively 40 nm ≦ Rz ≦
3. The hydrophilic member according to claim 1, wherein 200 nm and 300 nm ≦ Sm ≦ 1500 nm. 4. The method according to claim 1, wherein the hydrophilic metal oxide particles are SiO ₂ ,
Al ₂ O ₃ , photocatalytic TiO ₃ , ZrO ₂ and conductive Sn
The hydrophilic member according to any one of claims 1 to 3 from the group consisting of O ₂ comprises one or more selected. 5. The method according to claim 1, wherein the hydrophilic metal oxide particles have a first mode having a particle size of 3 nm or more and less than 40 nm, and a mode having a mode of 40 nm or more and 300 nm or less. The hydrophilic member according to any one of claims 1 to 4, further comprising a second hydrophilic metal oxide particle. 6. The mode of the particle size of the first hydrophilic metal oxide particles is 10 to 30 nm, and the mode of the particle size of the second hydrophilic metal oxide particles is 40. ~ 100nm
The hydrophilic member according to claim 5, which is: 7. The hydrophilic inorganic amorphous material contains at least one selected from the group consisting of amorphous silica, alkali silicate, alkali borosilicate, alkali zirconate, and metal phosphate. The hydrophilic member according to any one of claims 1 to 6. 8. The hydrophilic coating according to claim 1, wherein the surface of the hydrophilic coating has a zeta potential of −40 to 40 mV at pH = 7 and a static contact angle of water of the coating of 35 ° or less. 4. The hydrophilic member according to item 1. 9. The hydrophilic member according to claim 8, wherein the zeta potential is -30 to 30 mV. 10. The hydrophilic member according to claim 9, wherein the zeta potential is −25 to 0 mV. 11. The static contact angle is not more than 20 degrees,
A hydrophilic member according to claim 8. 12. The hydrophilic member according to claim 1, wherein the substrate is selected from the group consisting of an inorganic material, a metal material, an organic material, and a composite thereof. 13. The group consisting of tiles, sanitary ware, tableware, glass, mirrors, reflectors, protective plates, protective films, ceramics, calcium silicate plates, cement, wood, resins, metals, and ceramics. Claims 1 to 1 selected from
3. The hydrophilic member according to claim 1. 14. The method according to claim 14, wherein the substrate is glass, a glass lid, a mirror,
The hydrophilic member according to any one of claims 1 to 11, wherein the hydrophilic member is selected from the group consisting of a reflection plate, a protection plate, a film, and a protection film. 15. The hydrophilic member according to claim 1, wherein the substrate is a bathroom member. 16. The method according to claim 1, wherein the substrate is a bathroom mirror.
The hydrophilic member according to any one of claims 11 to 11. 17. A step of preparing a base material, and preparing a coating agent comprising at least alumina particles and an organometallic compound of hydrolyzable silicon which is a precursor of amorphous silica and / or a hydrolyzate thereof. Manufacturing a hydrophilic member, comprising: a step of coating the base material with the coating agent to form a coating; and, if necessary, a step of heat-treating at least a coating surface of the coating. Method. 18. A step of preparing a substrate, a step of preparing a first coating agent comprising at least hydrophilic metal oxide particles and a hydrophilic inorganic amorphous material, and coating the substrate with a first coating agent. Coating with an agent to form a first coating, if necessary, heat-treating at least the coated surface of the first coating, alumina particles and a hydrolyzable precursor of amorphous silica Providing a second coating agent comprising at least an organometallic compound of silicon and / or a hydrolyzate thereof; coating the first coating with a second coating agent; A method for producing a hydrophilic member, comprising: a step of forming; and, if necessary, a step of heat-treating at least a coated surface of the second coating. 19. The precursor of the hydrophilic inorganic amorphous substance is an alkali silicate, an alkali borosilicate, an alkali zirconate, a metal phosphate, an organometallic compound of hydrolyzable silicon, and hydrolysis. 20. The method for producing a hydrophilic member according to claim 18, comprising one or more selected from the group consisting of an organometallic compound of silicon. 20. The method according to claim 19, wherein the hydrophilic metal oxide particles are made of SiO.
_2, Al ₂ O _3, photocatalytic TiO _3, comprising one or more selected from ZrO ₂ and conductive SnO _2, the production method of the hydrophilic member according to claim 18 or 19. 21. The hydrophilic metal oxide particles may have 3 to 4 particles.
A first hydrophilic metal oxide particle having a mode of particle size at 0 nm and a second hydrophilic metal oxide particle having a mode of particle size at 40 to 300 nm at least. The method for producing a hydrophilic member according to any one of claims 18 to 20, wherein: 22. The hydrophilic inorganic amorphous substance SiO ₂
Weight and the hydrophilic metal oxide particles in a weight ratio of 10: 1 to 1
The weight ratio of the first hydrophilic metal oxide particles to the second hydrophilic metal oxide particles is 40: 1 to 1: 4. 22. The method for producing a hydrophilic member according to 21. 23. The method according to claim 17, wherein the ratio of the silica solid content of the alumina particles and the precursor of the amorphous silica is 3: 7 to 19: 1. A method for producing a hydrophilic member. 24. The coating agent further comprises at least one selected from the group consisting of boric acid, boric acid compounds, phosphoric acid, phosphoric acid compounds, and precursors of substances that become ZrO ₂ by heat treatment. 24. The method for producing a hydrophilic member according to any one of 17 to 23. 25. The heat treatment according to claim 25, wherein the surface temperature of the coated surface is 80.
It is carried out by raising the temperature to 500 ° C.
25. The method for producing a hydrophilic member according to any one of 24.