JP4438976B2 - Glass plate with water droplet adhesion prevention and heat ray blocking - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a glass plate that has both water droplet adhesion prevention and heat ray reflectivity.
[0002]
[Prior art]
Conventionally, glass is used for the window part of a house. However, this glass is cloudy when it is cold or rainy, and the visibility of windows is blurred due to rain or splashes. Further, when the moisture dries, the moisture and the stain on the glass surface remain in a spotted pattern. In any case, it becomes a factor that deteriorates the visibility of the window.
[0003]
Moreover, since it permeate | transmits a heat ray, a glass window part becomes a factor which reduces the air conditioning effect.
[Problems to be solved by the invention]
An object of the present invention is to provide a glass plate that has both water droplet adhesion prevention and heat ray reflectivity.
[0004]
[Means for Solving the Problems]
Invention of Claim 1 solves the subject regarding said glass plate, providing the heat ray reflective layer which consists of a resin layer containing aluminum powder and an ultraviolet absorber on at least one side of a transparent glass substrate, A substantially transparent surface layer containing photocatalyst particles, silicone or amorphous silica, and a water-repellent fluororesin is laminated on one side of a glass substrate, and the surface of the surface layer has a contact angle with water of 90 ° or more. It is characterized by being.
[0005]
The photocatalyst is photoexcited, and the organic group bonded to the silicon atom in the silicone molecule by photocatalysis is at least partially substituted with a hydroxyl group to exhibit hydrophilicity, and the silicone exhibits water repellency exposed to the outside air, The water-repellent fluororesin is exposed to the outside air and both water-repellent parts are microscopically dispersed on the surface, and the presence of the photocatalyst binds to silicon atoms in the silicone molecule in response to photoexcitation of the photocatalyst. The structure in which both the hydrophilic part and the water-repellent part are microscopically dispersed on the surface is because the silicone in which the organic group is at least partially substituted with a hydroxyl group permanently maintains hydrophilicity. Is maintained. In such a structure, since the hydrophilic surface and the water-repellent surface are adjacent to each other, the hydrophilic deposit that is easily adapted to the hydrophilic surface is not compatible with the adjacent water-repellent portion. Conversely, hydrophobic deposits that do not conform to the water-repellent surface also do not conform to the adjacent hydrophilic portion. Therefore, the hydrophilic deposit and the hydrophobic deposit are not fixed to the surface of the surface layer, and the surface is maintained in a clean state.
[0006]
Furthermore, even when amorphous silica is used in place of silicone, both the portion exhibiting water repellency where amorphous silica is exposed to the outside air and the portion exhibiting water repellency where water repellent fluororesin is exposed to the outside air are on the surface. Due to the microscopically dispersed structure and the presence of the photocatalyst, the amorphous silica remains permanently hydrophilic in response to photoexcitation of the photocatalyst, so that the hydrophilic portion and the water repellent portion A structure in which both are microscopically dispersed on the surface is maintained. In such a structure, since the hydrophilic surface and the water-repellent surface are adjacent to each other, the hydrophilic deposit that is easily adapted to the hydrophilic surface is not compatible with the adjacent water-repellent portion. Conversely, hydrophobic deposits that do not conform to the water-repellent surface also do not conform to the adjacent hydrophilic portion. Therefore, the hydrophilic deposit and the hydrophobic deposit are not fixed to the surface of the surface layer, and the surface is maintained in a clean state.
[0007]
As mentioned above, the contact angle with water on the surface of the glass plate is 90 ° or more, water is very difficult to adhere, and it is effective for the loss of visibility such as cloudy weather due to condensation in the cold or rainy weather, rain or splashing Can be prevented. In addition, it is possible to reduce dirt remaining when moisture dries. In addition, since the glass surface can be cleaned by flowing water or raining on the glass surface, it is also possible to remove the dirt in places where cleaning is not possible, such as high positions.
[0008]
By laminating the heat ray reflective layer on the glass plate, the heat retention is improved, and the glare of the light rays that are projected through the glass plate is eliminated. However, when dust or dirt adheres to the heat ray reflective layer, the reflected light from the aluminum powder contained in the heat ray reflective layer strikes the dust or dirt, thereby enhancing the presence thereof and deteriorating the aesthetic appearance. On the other hand, in the glass plate of the present invention, a substantially transparent surface layer containing photocatalyst particles, silicone or amorphous silica, and a water-repellent fluororesin is provided on the heat ray reflective layer, and the surface is clean. Therefore, the appearance is not impaired by the adhesion of dust.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view of a first embodiment of the glass plate of the present invention.
A glass substrate 1 is substantially composed of a coating film of silicone or amorphous silica containing a photocatalyst 3 and a water repellent fluororesin 4 through a heat ray reflective layer 2 comprising a resin layer containing aluminum powder and an ultraviolet absorber on one side. A transparent surface layer 5 is laminated.
[0010]
FIG. 2 shows a cross-sectional view of a second embodiment of the glass plate of the present invention.
A heat ray reflective layer 2 made of a resin layer containing aluminum powder and an ultraviolet absorber is deposited on the lower surface of the glass substrate 1, and a silicone or amorphous silica containing a photocatalyst 3 and a water-repellent fluororesin 4 on the upper surface. A substantially transparent surface layer 5 made of the above coating is laminated.
[0011]
FIG. 3 shows a cross-sectional view of a third embodiment of the glass plate of the present invention.
Heat-reflective layers 2a and 2b containing aluminum powder and an ultraviolet absorber are deposited on both surfaces of the glass substrate 1, and the photocatalyst 3 and the silicone containing the water-repellent fluororesin 4 are coated on the upper heat-reflective layer 2b. A substantially transparent surface layer 5 made of a regular coating film is laminated.
[0012]
In said 1st thru | or 3rd embodiment, soda-lime glass, tempered glass, acrylic glass, a polycarbonate resin board, a polymethylmethacrylate resin board etc. can be used as the glass base material 1. FIG. Moreover, you may provide the transparent intermediate layer which consists of a silica, silicone, etc. between the glass base material 1 and the heat ray reflective layer 2 for adhesiveness improvement.
[0013]
Next, as the heat ray reflective layer 2, a glass substrate 1 is formed on one or both sides of a glass substrate 1 with a thermosetting acrylic resin and an ultraviolet absorber and a thickness of 0.05 to 2.0 μm and an average diameter of 5 to 50 m. It is possible to apply a coating film having a heat ray reflection ultraviolet absorption ability to which aluminum foil powder is added and dispersed so as to form 1 to 10 μm to form a dry coating film. This heat ray reflective layer may be formed as a primer for the surface layer, or may be formed as a coating layer on the opposite surface of the glass substrate. A film containing a heat ray reflective layer may be bonded to the opposite surface of the glass substrate.
[0014]
The thermosetting acrylic resin paint includes alkyl methacrylates such as methyl methacrylate, butyl methacrylate and 2-ethylhexyl methacrylate, alkyl acrylates such as methyl acrylate, ethyl acrylate and butyl acrylate, glycidyl methacrylate, acrylamide, acrylonitrile, vinyl acetate, Vinyl ethers such as ethyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, at least one vinyl monomer exemplified by styrene, ethylene glycol dimethacrylate, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-glycol Sidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β (aminoethyl) γ-amino B be those derived from the pill at least one silane coupling agent such as triethoxy silane, it is necessary to contain the silane coupling agent 2 to 50% by weight.
[0015]
Further, the thermosetting acrylic resin is selected from peroxides such as dicumyl peroxide and benzoyl peroxide or azo compounds such as azobisisobutyronitrile in a solution containing the monomer and the silane coupling agent. It can be easily obtained by adding a radical polymerization catalyst and reacting under heating.
[0016]
Examples of the solvent for the thermosetting acrylic resin coating include diacetone alcohol, propylene biglycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, isobutyl alcohol, isobutyl alcohol, isopropyl alcohol, n-butyl alcohol, n- Examples thereof include propyl alcohol, xylene and toluene.
[0017]
Examples of the ultraviolet absorber include benzophenone, benzotriazole, cyanoacrylate, triazine, and salicylate. Particularly preferred are benzophenone ultraviolet absorbers, specifically 2hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2′-dihydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2′-dihydroxy-4,4′-diethoxybenzophenone, 2,2′-dihydroxy-4,4 '-Dipropoxybenzophenone, 2,2'-dihydroxy-4,4'-dibutoxybenzophenone, 2,2'-dihydroxy-4-methoxy-4'-ethoxybenzophenone, 2,2'-dihydroxy-4-methoxy- Examples thereof include 4′-butoxyphenone and 2,4-dihydroxybenzophenone.
[0018]
In the case where the light reflecting layer is laminated so that the surface of the layer is exposed as in the first and second embodiments, organotrialkoxysilane, colloidal is used in order to improve the weather resistance and scratch resistance. It is desirable to apply a colloidal silica-containing organosiloxane coating composed of silica and a solvent and heat cure to form a protective film.
[0019]
Next, when a photocatalyst is irradiated with light (excitation light) having an energy larger than the energy gap between the conduction band and the valence band of the crystal (ie, a short wavelength), excitation of the electrons in the valence band (photoexcitation) Refers to substances that can generate conduction electrons and holes, such as anatase-type titanium oxide, rutile-type titanium oxide, zinc oxide, tin oxide, ferric oxide, dibismuth trioxide, and tungsten trioxide. An oxide such as strontium titanate can be suitably used.
[0020]
For silicone, the average formula R _p SiO _{(4-p) / 2}
(In the formula, R is a functional group composed of one or more monovalent organic groups, or a functional group composed of two or more selected from monovalent organic groups and hydroxyl groups, and p is 0 <p. <A number satisfying 2) is applicable.
[0021]
Next, polytetrafluoroethylene, polychlorotrifluoroethylene, polyhexafluoropropylene, tetrafluoroethylene-hexafluoropropylene copolymer or the like can be applied as the water-repellent fluororesin.
[0022]
In a substantially transparent surface layer containing photocatalyst particles, silicone or amorphous silica, and a water-repellent fluororesin, in order for the surface layer to have a contact angle with water of 90 ° or more, the photocatalyst and fluororesin The blending ratio of the fluororesin with respect to the total amount of the regular silica is preferably 50% by weight or more, more preferably 60% by weight or more.
[0023]
Next, the thickness of the surface layer is preferably 0.4 μm or less. By setting the film thickness to 0.4 μm or less, white turbidity due to irregular reflection of light can be prevented, and the surface layer becomes substantially transparent. More preferably, it is 0.2 μm or less. Coloring of the surface layer due to light interference can be prevented. Further, the thinner the surface layer, the higher the transparency. Furthermore, if the film thickness is reduced, the wear resistance of the surface layer is improved.
[0024]
The above surface layer requires at least one side of a transparent glass substrate provided with a heat ray reflective layer on one side, a photocatalyst particle, a water-repellent fluororesin as well as a silicone precursor as well as water, ethanol, propanol Etc., catalysts that promote hydrolysis of silicone precursors such as hydrochloric acid, nitric acid, sulfuric acid, acetic acid, maleic acid, basic compounds such as tributylamine, hexylamine, aluminum triisopropoxide, tetraisopropyl Coating compositions that contain a catalyst that cures silicone precursors such as titanate and other silicone precursors and surfactants that improve the dispersibility of coating liquids such as silane coupling agents can be applied to spray coating and dip coating. Coating method, flow coating method, spin coating method, roll coating Law, brushing, applying by a method sponge coating, etc., the heat treatment can be formed by standing at room temperature, to more polymerization curing of ultraviolet irradiation.
[0025]
Example 1
(Adjustment of primer coating for forming a heat ray reflective layer) In a 500 ml separable flask with a Dimroth condenser, 40 parts of γ-methacryloxypropyltrimethoxysilane, 40 parts of methyl methacrylate, 5 parts of ethyl acrylate, 5 parts of vinyl acetate, glycidyl methacrylate 10 parts, 0.2 part of ethylene glycol dimethacrylate, 0.5 part of azobisisobutyl nitrile as a polymerization catalyst, 20 parts of diacetone alcohol and 80 parts of ethylene glycol monomethyl ether as a solvent, and 80 to 90 ° C. under a nitrogen stream For 5 hours. The viscosity of the obtained thermosetting acrylic resin solution was 38500 cst, and the alkoxysilyl group content in the copolymer was 40% by weight. Next, it adjusted with the mixed solvent which made the ratio of diacetone alcohol and ethylene glycol monomethyl ether 20/80 so that the obtained resin solution might be 10% of non volatile matter. The viscosity of the primer paint obtained by this adjustment was 20 to 40 cst.
[0026]
The primer paint obtained as described above was dissolved by adding 13 parts by weight of 2,4-dihydroxybenzophenone as an ultraviolet absorber to 100 parts by weight of the solid content in the thermosetting acrylic paint. 50 parts by weight of aluminum paste (made by Silver Line, trade name: SS-6246AR, average thickness 0.2 μm, average diameter 16.0 μm, hue silver, aluminum powder amount 64% by weight) with respect to the solid content in the paint The added and dispersed coating liquid was applied to a soda-lime glass plate using a flow method so as to have a dry coating film thickness of 5 μm, and cured at about 120 ° C. for about 30 minutes to form a heat ray reflective layer.
[0027]
Next, a substantially transparent surface layer containing photocatalyst particles, silicone, and a water-repellent fluororesin was formed on the heat ray reflective layer as follows.
[0028]
On the heat ray reflective layer, anatase-type titanium oxide sol (Nissan Chemical, TA-15), silica sol (Nippon Synthetic Rubber, Glasca A solution), methyltrimethylmethoxysilane (Nippon Synthetic Rubber, Glasca B solution) and poly Coating liquid obtained by mixing tetrofluoroethylene (PTFE) particles (Daikin Industries, Lubron L-5) and ethanol and stirring for 2 to 3 hours is applied onto a 10cm square soda lime glass plate by spray coating. Then, it was treated at 200 ° C. for 15 minutes to form a coating film comprising 33 parts by weight of anatase-type titanium oxide particles, 66 parts by weight of polytetrafluoroethylene particles, 6 parts by weight of silica, and 5 parts by weight of silicone. The surface of the coating film was irradiated with an ultraviolet light source at an ultraviolet illuminance of 0.3 mW / cm ² for 1 day to obtain a substantially transparent surface layer containing photocatalyst particles, silicone, and a water-repellent fluororesin. . The contact angle of the surface layer with water was 97.2 °, and when the glass plate was tilted, the water drops fell while rolling.
[0029]
This glass plate is provided with a heat ray reflective layer on one side of glass, and a substantially transparent surface layer containing photocatalyst particles, silicone and water repellent fluororesin is laminated on the heat ray reflective layer, Since the surface has a contact angle with water of 90 ° or more, it is used as a window glass, blocks heat rays, has excellent heat retention, and has no glare, and the surface is kept clean. As a result, it was possible to form a highly transparent window in which the appearance was not impaired by the adhesion of dust.
[0030]
(Example 2)
A heat ray reflective layer is formed on one side of a soda-lime glass plate in the same manner as in Example 1, and a colloidal silica-containing organopolysiloxane coating composed of organotrialkoxysilane, colloidal silica, and a solvent is further formed thereon and cured by heating. Thus, a protective film was formed. Further, a substantially transparent surface layer containing photocatalyst particles, silicone and water repellent fluororesin was formed on the other surface of the glass plate in the same manner as in Example 1.
[0031]
The glass plate obtained is used as a window glass in a house, cuts off heat rays, has excellent heat retaining properties, has no glare, and maintains a clean surface. It was possible to form a highly transparent window that was never seen.
[0032]
(Example 3)
A substantially transparent surface layer containing a heat ray reflective layer and photocatalyst particles, silicone, and a water-repellent fluororesin was formed on both surfaces of the soda-lime glass plate in the same manner as in Example 1. Next, a heat ray reflective layer is formed on the other surface of the glass plate, and a colloidal silica-containing organopolysiloxane coating composed of organotrialkoxysilane, colloidal silica and a solvent is further formed on the heat ray reflective layer, followed by heat curing. Thus, a protective film was formed.
[0033]
Using the obtained glass plate as a window glass, heat rays are cut off, heat retention is excellent, and there is no feeling of glare, and the surface is maintained in a clean state. It was possible to form a highly transparent window.
[0034]
【The invention's effect】
As described above in detail, the glass plate of the present invention is provided with a heat ray reflective layer on at least one side of a transparent glass substrate, and photocatalyst particles and silicone or amorphous silica and water repellency are provided on one side of the glass substrate. A substantially transparent surface layer containing a fluororesin is laminated, and the surface of the surface layer has a contact angle with water of 90 ° or more, so that it blocks heat rays and is excellent in heat retention. Since there is no glare and the surface is kept clean, it has the advantage that the aesthetics are not impaired by the adhesion of dust.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a first embodiment of a glass plate of the present invention.
FIG. 2 is a cross-sectional view of a second embodiment of the glass plate of the present invention.
FIG. 3 is a cross-sectional view of a third embodiment of the glass plate of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Heat ray reflective layer 3 Photocatalyst 4 Water-repellent fluororesin 5 Surface layer

Claims (1)

A heat ray reflective layer composed of a resin layer containing aluminum powder and an ultraviolet absorber is provided on at least one side of a transparent glass substrate, and photocatalyst particles, silicone or amorphous silica, and a water-repellent fluororesin are provided on one side of the glass substrate. A glass plate having water droplet adhesion preventing properties and heat ray blocking properties, wherein a substantially transparent surface layer is laminated, and the surface of the surface layer has a contact angle with water of 90 ° or more.

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