JPH06192598A - Ultraviolet ray absorbing glass - Google Patents

Abstract

PURPOSE:To obtain a glass capable of suppressing coloring of reflected light without lowering transmittance of visible light and excellent in heat radiation- reflecting property and useful for car, etc., by forming a specific intermediate film between an ultraviolet ray absorbing film and glass. CONSTITUTION:The glass is obtained by forming an intermediate film having a refractive index of (nfXng)<1/2> which is a intermediate of a refractive index nf of a ultraviolet ray absorbing film and a refractive index ng of glass having a heat radiation-reflecting performance and simultaneously an optical film thickness of lambda/4 wavelength of visible light having 400-700nm wavelength. between an ultraviolet ray absorbing film consisting essentially of one or more compounds among zinc oxide, titanium oxide and cerium oxide on the glass surface and the glass.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet absorbing glass having an ultraviolet absorbing film formed on the glass surface.

[0002]

2. Description of the Related Art It is important to shield ultraviolet rays entering a room or the inside of a vehicle in order to prevent not only sunburn of a human body but also deterioration of ornaments in the room or the vehicle.

Conventionally, organic compounds such as benzophenone and benzotriazole have been mainly known as ultraviolet absorbers, but these organic compounds have a problem that they are prone to deterioration due to absorption of ultraviolet rays. It was

Therefore, from the viewpoint of no deterioration, several methods have been proposed for forming an ultraviolet absorbing glass by forming a film of an inorganic compound such as zinc oxide, titanium oxide or cerium oxide having an ultraviolet absorbing property on the surface of the glass. It has been.

On the other hand, in the summer, heat from sunlight raises the temperature in the room and reduces the cooling efficiency. Therefore, in order to prevent this, it is necessary to impart heat ray reflectivity to glass for automobiles, construction, etc. As a result, it has become an important issue to limit the invasion of solar radiation into the room and improve the cooling efficiency.

The current heat ray-reflecting glass is mainly obtained by forming a coating film of a noble metal, a conductive metal oxide, a nitride, etc. on the surface, but these thin films have poor ultraviolet absorption. In addition, there is a problem in that visible light is remarkably absorbed depending on the material, and the material cannot be used in a site requiring high visible light transmittance such as automobiles and general construction.

[0007]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the above-mentioned problems of the prior art, and to provide a glass having both ultraviolet absorption and heat ray reflectivity and high visible light transmittance. It is intended to be newly provided.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, in which zinc oxide on the glass surface,
In an ultraviolet absorbing glass on which an ultraviolet absorbing film containing at least one of titanium oxide and cerium oxide as a main component is formed, between the ultraviolet absorbing film and the glass, the refractive index of the ultraviolet absorbing film and the refractive index of the glass are The present invention provides an ultraviolet-absorbing glass having an intermediate film having an intermediate refractive index and heat ray reflecting performance.

Examples of the ultraviolet absorbing film of the present invention include a film containing at least one of zinc oxide, titanium oxide and cerium oxide as a main component, and specifically, ZnO,
_{TiO 2, CeO 2, ZnO-} TiO 2, ZnO-Ce
O _2, TiO ₂ -CeO ₂ or ZnO-TiO ₂ -C
A film made of eO ₂ or the like can be mentioned, and these components can further contain other components.

Of these, CeO ₂ --TiO ₂ type ultraviolet absorbing films are preferable because they are excellent in ultraviolet absorbing properties, and have excellent surface hardness and chemical durability. However, since the film of this system has a very high refractive index, and there is a possibility that the high reflectance causes a decrease in the visible light transmittance, a low refractive material such as SiO ₂ is added to increase the refractive index of the film. 1.9-2.
It is preferably about 1. As described above, it is particularly preferable to reduce the refractive index of the ultraviolet absorbing film and to pay attention to the optical characteristics of the intermediate film formed thereunder, since the decrease of the visible light transmittance is prevented while maintaining the high ultraviolet absorbing performance.

As a specific composition ratio (weight ratio) for providing effective ultraviolet absorption and high durability and preventing the reflectance from increasing, for example, CeO ₂ / Ti is used.
_{O 2 / SiO 2 = 1.0~5.0 /} 1.0 / 0.5~
It is 1.5.

The ultraviolet absorbing film of the present invention has an ultraviolet absorbing ability,
100 nm or more 8 considering visible light transmittance, film strength, etc.
It preferably has a film thickness of 00 nm or less.

In the present invention, it is important that the intermediate film has a refractive index intermediate between the refractive index of the ultraviolet absorbing film and the refractive index of glass.

From the viewpoint of suppressing reflection of visible light and increasing reflection in the near infrared region, the refractive index of the intermediate film is particularly preferably non-reflective, that is, the refractive index of the ultraviolet absorbing film is n _f. , And the refractive index of glass is _ng ,
It is a case of forming an intermediate layer having _{n m = (n f × n} g) 1/2 refractive index such as to establish the refractive index n _m of the intermediate layer. In practice, (n _f × n _g ) ^1/2 ± 10%
It does not matter if the refractive index is in the range.

Although the film thickness of the intermediate film is not particularly limited, in order to suppress the color unevenness due to the film thickness unevenness of the ultraviolet absorbing film, it is 4
Transparent film having an optical thickness of lambda / 4 wavelength of visible light 00～700Nm, i.e., the optical thickness n _m d (d is film thickness),
λ _0/4 (λ ₀ is the desired design wavelength) is preferably. Incidentally, practically, no problem even in the optical thickness of λ _0/4 ± 10% range.

In this case, if the intermediate film has an optical film thickness of λ / 4 wavelength of visible light, the non-reflective condition is satisfied for visible light. Therefore, the reflected light at the interface between the ultraviolet absorbing film and the intermediate film ( R1) and light reflected at the interface between the interlayer film and the glass (R
Since the amplitude (intensity) of 2) is equal and the phases are opposite, R1 and R2 are attenuated by combining, and the reflectance is reduced. On the other hand, in the near-infrared ray whose wavelength is longer than that of visible light, the antireflection condition is no longer satisfied, and the phases are aligned.
And R2 will be amplified by synthesis, resulting in a high reflectance in this region.

Further, when the intermediate film is formed under such conditions, visible light is reflected substantially only at the interface between the air on the outermost surface and the ultraviolet absorbing film. It also has an effect of preventing coloring of reflected light due to interference of reflection.

The composition of the intermediate film of the present invention includes:
Films satisfying the above optical characteristics, such as SiO ₂ and Ge
O ₂ , Al ₂ O ₃ , ZrO ₂ , TiO ₂ , SnO ₂ , I
The material is not particularly limited as long as it is a transparent film containing n ₂ O ₃ , Ta ₂ O ₅ , ZnO, CeO ₂ or the like, or a mixture thereof, for example, ZrO ₂ —SiO _{2 and the} like. From the viewpoint of enhancing the absorption ability, it is preferable that the intermediate film also contains an ultraviolet absorbing oxide such as zinc oxide, titanium oxide, or cerium oxide. A specific example, ZnO-SiO _2, ZnO
_{-Al 2 O 3, ZnO-GeO} 2, TiO 2 -SiO
_{2, TiO 2 -Al 2 O 3} , TiO 2 -GeO 2, Ce
_{O 2 -SiO 2, CeO 2 -Al} 2 O 3, CeO 2 -G
Two-component system such as eO ₂ or ZnO, TiO
_It is a three-component system or a four-component system in which one or more components selected from ₂ and CeO ₂ are added.

Further, a heat conductive property can be enhanced by adding a conductive component to the intermediate film. These conductive _{components, Sb-SnO 2, Sn-} In 2 O 3 or Al-Z
nO etc. can be mentioned.

In the present invention, having a heat ray reflecting property means, for example, one having a heat shielding ability (ratio of difference between solar radiation transmittance of glass and visible light transmittance) of 1 or more. .

It is also possible to enhance the heat ray reflection performance by dispersing the ultrafine particles of the conductive component in the intermediate film or forming the intermediate film into a conductive film.

The method of forming the ultraviolet absorbing film and the intermediate film in the present invention is not particularly limited, and the method conventionally used for forming a film, that is, a dry method such as a vacuum vapor deposition method, a sputtering method or a CVD method can be used to obtain a sol-gel. Method, spray pyrolysis method, wet method such as coating pyrolysis method,
Wide choice.

[0023]

The present invention will be further described below with reference to examples of the present invention, but the present invention is not limited thereto. The films obtained in the following Examples and Comparative Examples were evaluated by appearance (visual inspection), ultraviolet transmittance (T _uv : ISO-905).
0), visible light transmittance (T _v : JIS-R3106),
Solar transmittance (T _E : JIS-R3106), heat shielding ability (ratio of difference between solar transmittance of glass and visible light transmittance, ΔT _E
/ ΔT _V ) and chroma (C ^* : (a ^{* 2} + b ^{* 2} ) ^1/2 in CIEL ^* a ^* b ^* ).

Example 1 22 g of 1-propanol, 7 g of acetylacetone and 30 g of cerium nitrate were mixed and dissolved and stirred overnight (A
liquid). Liquid A (26 g), ethyl silicate 40 (3.6 g), and titanium acetylacetonate (Ti (OPr) ₂ (Acac) ₂ ) were added to 58 g of 2-propanol at 8.7 g and 0.
Coating solution B was prepared by mixing 0.6 g of 1N-hydrochloric acid aqueous solution. 4.5 g of ethyl silicate 40, 4.3 g of tetraisopropyl titanate and 3.0 g of 0.1N-hydrochloric acid aqueous solution were sequentially added to ethanol and mixed well to prepare a coating liquid C.

Coating solution C was coated on soda lime glass ( _ng = 1.52) by spin coating at 200 ° C.
By firing for 30 minutes at a refractive index of 1.74 and a film thickness of 68 nm.
An intermediate film (TiO ₂ : SiO ₂ = 40/60 by weight) composed of an iO ₂ —SiO ₂ transparent film was obtained. in addition,
The coating solution B is applied by a spin coating method and baked at 600 ° C. for 5 minutes to be a CeO ₂ —TiO ₂ —SiO ₂ -based ultraviolet absorbing film (weight ratio CeO ₂ : TiO ₂ : SiO ₂ = 6).
4/18/18) was formed. The ultraviolet absorption film had a refractive index of 2.05 and a film thickness of 180 nm. The results of the optical characteristics are shown in Table 1.

Example 2 Ethyl silicate 40, tetraisopropyl titanate and 0.2N-hydrochloric acid aqueous solution were sequentially added to ethanol and mixed well to prepare an intermediate film forming coating solution, which was applied onto soda lime glass by spin coating. 30 at 200 ℃
TiO ₂ with a refractive index of 1.72 and a film thickness of 75 nm after firing
-Intermediate film consisting of a SiO ₂ -based transparent film (TiO 2 in weight ratio)
₂ : SiO ₂ = 38/62) was obtained.

A cerium oxide colloid sol (Taki Chemical Co., Ltd .: trade name Nidral U-15) was applied thereon by a spin coating method and baked again at 200 ° C. for 30 minutes to form an ultraviolet absorbing film, which was then subjected to ultraviolet absorption. I got a glass. The cerium oxide coating had a refractive index of 1.95 and a thickness of 290 nm. The characteristics of the obtained ultraviolet absorbing glass are shown in Table 1.

Example 3 Ethyl silicate, cerium nitrate and acetylacetone were sequentially added to ethanol to prepare an intermediate film coating solution, which was applied onto soda lime glass by spin coating and baked at 400 ° C. for 10 minutes to obtain a refractive index of 1 Ce of 68.68 and film thickness of 68 nm
Intermediate film consisting of O ₂ —SiO ₂ transparent film (C by weight ratio)
eO ₂ : SiO ₂ = 40/60) was obtained. On top of that, zinc oxide ultrafine particle dispersion coating liquid (Sumitomo Cement: trade name Z
C-120M) was applied by a spin coating method and the same treatment as in Example 1 was carried out to form an ultraviolet absorbing film to obtain an ultraviolet absorbing glass. The refractive index of the zinc oxide coating is 1.88,
The film thickness was 520 nm. The characteristics of the obtained ultraviolet absorbing glass are shown in Table 1.

Example 4 The intermediate film shown in Example 1 was prepared by using antimony-containing tin oxide ultrafine particles having an average particle diameter of 10 nm in a weight ratio of SiO ₂ / TiO _2.
UV light was obtained in the same manner as in Example 1 except that a film having a refractive index of 1.73 and a film thickness of 70 nm was formed by using a coating liquid dispersed so that ₂ / Sb-SnO ₂ = 30/10/60. An absorption glass was created. The characteristics of this glass are shown in Table 1.

Comparative Example An ultraviolet absorbing glass was prepared by forming an ultraviolet absorbing film on glass in the same manner as in Example 1 without forming the intermediate film shown in Example 1. The characteristics of this glass are shown in Table 1.

[0031]

[Table 1]

[0032]

As described above, according to the present invention, heat ray reflectivity can be imparted to the ultraviolet absorbing glass without lowering the visible light transmittance, and coloring of reflected light of visible light can be suppressed. In addition, the application of UV-absorbing glass will be expanded to fields such as automobiles and construction.

Claims (6)

[Claims] 1. An ultraviolet absorbing glass having a glass surface on which an ultraviolet absorbing film containing at least one of zinc oxide, titanium oxide and cerium oxide as a main component is formed. An ultraviolet-absorbing glass, wherein an intermediate film having a refractive index intermediate between the refractive index of the absorbing film and the refractive index of glass and having heat ray reflecting performance is formed. 2. The intermediate film has a refractive index n _f of the ultraviolet absorbing film,
When the refractive index of the glass and n _g, the refractive index n _m of the intermediate _{layer, n m = (n f ×} n g) of claim 1, wherein the ^half is an intermediate layer, such as to establish UV absorbing glass. 3. The ultraviolet absorbing glass according to claim 1, wherein the intermediate film has an optical film thickness of λ / 4 wavelength of visible light of 400 to 700 nm. 4. The intermediate film contains at least one of zinc oxide, titanium oxide, and cerium oxide, and is provided with ultraviolet ray absorbing ability as well as heat ray reflecting ability. The ultraviolet absorbing glass according to any one of 1. 5. The ultraviolet absorbing glass according to claim 1, wherein the ultraviolet absorbing film is made of cerium oxide, titanium oxide and silicon oxide. 6. The intermediate film contains a conductive component, whereby the heat ray reflectivity is further enhanced.
5. The ultraviolet absorbing glass according to any one of item 5.