JPH0859289A - Method for producing ultraviolet light-sharply cutting glass for high brightness light source - Google Patents

Abstract

PURPOSE: To obtain colorless and transparent glass excellent in solarization- resistant characteristics against high brightness infrared light by preparing raw glass having a specific composition, and subsequently heating the raw glass to deposit the fine particles of CuCl2 and/or CuBr2 . CONSTITUTION: Raw glass having a composition comprising SiO2 : 62-80-mol.%, B2 O3 : 10-20mol.%, Al2 O3 : 1-10mol.%, Li2 O+Na2 O+K2 O: 5-15mol.% copper oxide: 0.01-2mol.% in terms of CuO, Cl+Br: 0.01-2mol.%, the oxides of tin and antimony: 0.1-3mol.% in terms of SnO and Sb2 O3 , the oxide of one or more metals selected from iron, lead, cerium, titanium and bismuth: 0.01-5mol.% is prepared, heated and melted at 1200-1800 deg.C for 5min to several days, and subsequently molded into a prescribed shape. The fine particles of CuCl2 and/or CuBr2 can be deposited by a thermal treatment at 500-730 deg.C for 0.1-4hrs. The deposited fine particles of the CuCl2 and/or the CuBr2 have a particle diameter of 0.5-400nm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an ultraviolet sharp cut glass for a high brightness light source such as a mercury lamp or a metal halide lamp.

[0002]

2. Description of the Related Art Heretofore, as glass for cutting off ultraviolet rays, there have been known ones which are commercially available as so-called ultraviolet sharp cut glasses and cover glasses for protecting solar cells of artificial satellites from ultraviolet rays. These glasses shield ultraviolet rays by utilizing the absorption in the ultraviolet region of glasses doped with various ions. However, glass doped with these ions
Since the rate of change in transmittance with respect to wavelength near the ultraviolet absorption edge is relatively gentle, absorption in the visible region cannot be avoided in order to cut near-ultraviolet light, and the glass becomes yellow, In addition, there is a problem that the near-ultraviolet region cannot be cut with colorless glass that does not absorb in the visible region.
Also, in order to eliminate this drawback, Japanese Patent Publication No. 46-346
4, JP-A-4-18501, JP-A-4-275942,
Japanese Patent Laid-Open No. 5-13235 proposes an ultraviolet absorbing glass having a small wavelength inclination width. This glass is characterized by precipitating CuCl or CuBr crystals in the glass.

[0003]

However, when these glasses are exposed to a high-intensity light source, such as a high-pressure mercury lamp or a metal halide lamp, which emits strong ultraviolet rays, there is a problem that the glass is colored by solarization. However, it was insufficient as a glass for a high brightness light source.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems of the prior art and to provide a method for producing an ultraviolet sharp cut glass for a high brightness light source which is colorless and is less likely to cause solarization by ultraviolet rays.

[0005]

[Means for Solving the Problems] In the present invention, copper oxide is expressed as CuO in terms of CuO of 0.01 to 2% Cl + Br 0.01 to 2% Tin and antimony oxides of SnO and Sb ₂ O, respectively. in terms of ₃ to prepare a raw glass containing _{2 O 3 0.01~ 3% SnO +} Sb, Cu by heat-treating raw glass
In the production of UV sharp cut glass for high-brightness light sources by precipitating Cl or / and CuBr fine particles, the raw glass contains 0.001 to 5 mol% of at least one oxide selected from iron, lead, cerium, titanium and bismuth. It is a method for producing an ultraviolet sharp cut glass for a high-brightness light source.

The ultraviolet sharp cut glass for a high-intensity light source produced by the present invention has CuCl or / and CuBr fine particles (crystals) having a very sharp absorption in the ultraviolet region, which are deposited in the visible region. It is possible to selectively block only the ultraviolet rays without absorbing the above-mentioned light and has a solarization resistance property against the high-intensity ultraviolet rays.

The present invention provides CuCl and / or CuBr by preparing a raw glass having the above-mentioned specific composition and heat-treating it.
It deposits fine particles. First, the reason for limiting the raw glass will be described.

In the base glass of the present invention, in order to deposit CuCl or / and CuBr fine particles in the glass, copper is 0.01 to 3 mol% as CuO in terms of oxide, and Cl or / and Br is O.O1 to 2 It is necessary to contain it by mol%. Cu
When O 2 is less than 0.01 mol%, CuCl and / or CuBr fine particles are not sufficiently precipitated and the ultraviolet ray shielding performance is insufficient. On the other hand, even if it exceeds 3 mol%, the ultraviolet shielding performance is not further improved, and conversely, giant particles of CuCl or / and CuBr fine particles are deposited and the transparency of the glass is lost. The mixing ratio of Cl and Br is appropriately selected depending on the shielding wavelength.

If the sum of Cl and Br is less than 1 mol% O.O, Cu
Cl or / and CuBr fine particles are not sufficiently deposited and the ultraviolet ray shielding performance is not sufficient. On the other hand, even if it exceeds 2 mol%, the ultraviolet ray shielding performance is not further improved, and conversely, phase separation of the glass is likely to occur and the transparency of the glass may be lost. Note that C
l and Br may be used alone.

The oxides of tin and antimony are respectively SnO.
, Sb ₂ O ₃ converted to a total content of 0.01 to 3 mol%, the glass is not colored blue or green, and CuCl or / and CuBr fine particles are more likely to be deposited. SnO, Sb
_{When the} total content of ₂ O ₃ is less than 0.01 mol%, the glass tends to be colored blue or green. On the contrary, when it exceeds 3 mol%, the glass is colored red and a colorless product is obtained. It is hard to be caught.

Oxides of iron, lead, cerium, titanium and bismuth act to improve the solarization resistance to ultraviolet rays. If the total amount of these oxides is less than 0.001 mol%, there is almost no effect. On the contrary, if the total amount exceeds 5 mol%, copper colloids are precipitated in the glass and the glass turns red. Or, the glass is colored yellow due to the influence of these components, and it is difficult to obtain a colorless glass. Of these, bismuth oxide is preferable because it has a large effect. In particular, those containing 0.1 to 3 mol% of bismuth oxide are most suitable as the raw glass in the present invention.

As the composition of the raw glass, the following two types are preferable in order to suppress clouding and red coloration during glass forming and heat treatment and to improve chemical durability.

The composition of the first type of raw glass is mol%
Indication, SiO ₂ 62-80% B ₂ O ₃ 10-20% Al ₂ O ₃ 1-10% Li ₂ O + Na ₂ O + K ₂ O 5-15% Copper oxide 0.01- 2% Cl + Br 0.01 to 2% Tin and antimony oxides are converted into SnO and Sb ₂ O ₃ , respectively SnO + Sb ₂ O ₃ 0.01 to 3% At least selected from iron, lead, cerium, titanium and bismuth. Consists of 0.001 to 5% of a kind of oxide.

In such a raw glass, the content of SiO ₂ is
If it is less than 62 mol%, clouding of the glass or coloring due to copper colloid is likely to occur due to the phase separation of the glass. Conversely, if it exceeds 80 mol%, the glass formation temperature becomes high, and C
Any of these is not preferable because the volatilization of u, Cl and Br components increases.

When the content of B ₂ O ₃ is less than 10 mol%, Cu
Precipitation of Cl and CuBr is difficult to obtain, and conversely, if it exceeds 20 mol%, the chemical durability of the glass becomes low, so neither is preferable. If the Al ₂ O ₃ content is less than 1 mol%, the glass tends to become cloudy due to phase separation, while if the Al ₂ O ₃ content exceeds 10 mol%, vitrification tends to be difficult, which is not preferable.

When the total content of Li ₂ O, Na ₂ O and K ₂ O is less than 5 mol%, the glass formation temperature becomes high and Cu and C are contained.
Both l and Br components are volatilized. On the other hand, when the total amount exceeds 15 mol%, copper colloids are likely to precipitate in the glass to cause red coloration and the chemical durability is lowered, which is not preferable. Note that when the ratio of Li ₂ O to the total amount of Li ₂ O, Na ₂ O, and K ₂ O is 0.25 or more, Cu having a controlled grain size is formed.
Particularly preferred is that Cl or / and CuBr fine particles can be easily deposited.

Of these, particularly preferred glass bases are as follows.

SiO ₂ 63 to 72% B ₂ O ₃ 12 to 18% Al ₂ O ₃ 2 to 8% Li ₂ O + Na ₂ O + K ₂ O 7 to 13% Copper oxide in terms of CuO 0.1 to 1.5% Cl + Br 0.1 to 1.5% The oxides of tin and antimony are converted into SnO and Sb ₂ O ₃ , respectively, and are composed of SnO + Sb ₂ O ₃ 0.05 to 2% bismuth oxide 0.1 to 3%.

On the other hand, the composition of the second elemental glass is expressed in mol%, SiO ₂ 50 to 80% B ₂ O ₃ 10 to 30% Al ₂ O ₃ 1 to 20% Li ₂ O + Na ₂ O + K ₂ O 5 to 20% ZrO ₂ 0.3 to 10% Copper oxide is CuO equivalent 0.01 to 2% Cl 0 to 2% Br 0 to 2% Cl + Br 0.01 to 2% Tin and antimony oxides are SnO, respectively. , Sb ₂ O ₃ , SnO + Sb ₂ O ₃ 0.01 to 3% 0.001 to 5% of at least one oxide selected from iron, lead, cerium, titanium and bismuth.

In such a raw glass, the content of SiO ₂ is
If it is less than 50 mol%, the chemical durability of the glass is insufficient. Conversely, if it exceeds 80 mol%, the glass formation temperature becomes high and the Cu, Cl, and Br components volatilize. Neither is preferable.

When the content of B ₂ O ₃ is less than 10 mol%, Cu
Precipitation of Cl and CuBr is difficult to obtain, and conversely, if it exceeds 30 mol%, the chemical durability of the glass becomes low, so neither is preferable. If the Al ₂ O ₃ content is less than 1 mol%, the glass tends to become cloudy due to phase separation, while if the Al ₂ O ₃ content exceeds 20 mol%, vitrification becomes difficult, which is not preferable.

If the total content of Li ₂ O, Na ₂ O and K ₂ O is less than 5 mol%, the glass formation temperature becomes high and Cu and C
Both l and Br components are volatilized. On the other hand, when the total amount exceeds 15 mol%, copper colloids are likely to precipitate in the glass to cause red coloration and the chemical durability is lowered, which is not preferable. Note that when the ratio of Li ₂ O to the total amount of Li ₂ O, Na ₂ O, and K ₂ O is 0.25 or more, Cu with a controlled grain size is formed.
Particularly preferred is that Cl or / and CuBr fine particles can be easily deposited.

When the ZrO ₂ content is less than 0.3 mol%,
When glass is formed, white turbidity occurs due to phase separation, and copper colloid precipitates easily during the heat treatment, causing glass to turn red. On the other hand, when it exceeds 10 mol%, the glass formation temperature rises and Cu, Cl, and Br components volatilize. This is not preferable either.

Of these, the particularly preferable raw glass is as follows.

SiO ₂ 55-75% B ₂ O ₃ 12-25% Al ₂ O ₃ 2-15% Li ₂ O + Na ₂ O + K ₂ O 7-17% ZrO ₂ 0.3-3% Copper oxide Converted to CuO 0.1 to 2% Cl 0 to 2% Br 0 to 2% Cl + Br 0.1 to 2% TinO and Sb ₂ O ₃ are converted into SnO and Sb ₂ O ₃ , respectively, and SnO + Sb ₂ O ₃ 0.05 to 2% Bismuth oxide 0.1 to 3%.

The particle size of CuCl and / or CuBr fine particles to be deposited is preferably 0.5 to 400 nm. Particle size 0.5
If it is less than nm, the absorption of CuCl and / or CuBr is not sufficient and the expected ultraviolet ray shielding is insufficient.
If it exceeds nm, visible light is scattered in the glass and the transparency of the glass is lost, which is not preferable. Within this range, a particle size of 1 to 100 nm is particularly preferable because it sufficiently shields ultraviolet rays and makes the glass transparent to visible light.

Examples of raw materials used in the production of the ultraviolet sharp cut glass of the present invention include the following substances.

Examples of raw materials for copper, chlorine and bromine include chlorides and bromides of copper such as CuCl, CuCl ₂ , CuBr and CuBr _2, and copper as a simple substance of copper or an oxide or hydroxide of copper.
Inorganic salts such as sulfate and organic salts can be used. Further, chlorine and bromine can be supplied as alkali chloride, alkali bromide, ammonium chloride, ammonium bromide and chlorides and bromides of other additive components. Furthermore,
Chlorine and bromine can be introduced as a simple substance or as a gas of chloride or bromide by reacting with glass.

As a raw material of tin, stannous oxide (SnO),
In addition to oxides such as stannic oxide (SnO ₂ ), chlorides and organotin compounds can be used.

As the raw material of antimony, in addition to oxides such as antimony trioxide (Sb ₂ O ₃ ) and antimony pentoxide (Sb ₂ O ₅ ) and complex oxides such as sodium pyroantimonate,
Chlorides and organic antimony compounds can be used.

Examples of raw materials for iron, lead, cerium, titanium and bismuth include iron oxide (Fe ₂ O ₃ , FeO), lead oxide (PbO, Pb ₃ O ₄ ), cerium oxide (CeO ₂ ), titanium oxide ( In addition to oxides such as TiO ₂ ) and bismuth oxide (Bi ₂ O ₃ , Bi ₂ O ₅ ), nitrides and organometallic compounds can be used.

As the silicon raw material, for example, a silicon oxide such as silicon dioxide, a nitride, an organic silicon compound, or a silicate such as an alkali silicate can be mixed with another alkali compound.

As boric acid raw material, boric acid (H ₃ BO ₃ ),
In addition to oxides such as anhydrous boric acid (B ₂ O ₃ ), nitrides, organoboron compounds, and borate salts such as alkali borate can be used as a mixture with other alkali compounds.

As the aluminum raw material, hydroxides and oxides such as aluminum hydroxide (Al (OH) ₃ ) and alumina (Al ₂ O ₃ ) as well as nitrides and organic aluminum compounds can be used.

Typical examples of the alkali metal raw material are carbonates, but other alkali compounds such as hydroxides and chlorides can be appropriately used.

As a raw material of iron, iron alone, iron oxides or halides can be used.

As zirconium raw materials, in addition to oxides such as zirconium oxide (ZrO ₂ ), chlorides, complex oxides such as organozirconium compounds and zircon (ZrSiO ₄ ) may be mixed with other silicon compounds. You can

Further, in order to control the redox of the glass melt to make the glass colorless, an oxidizing agent such as nitrate or sulfate or a reducing agent such as carbon may be appropriately added to the raw material batch.

The means for producing the ultraviolet sharp cut glass of the present invention is not particularly limited, and for example, various raw materials are weighed and mixed in a predetermined amount, and the mixture is heated and melted at 1200 to 1800 ° C. for 5 minutes to several days, and then predetermined. A method of forming into a shape is used. CuCl or / and CuBr fine particles are 500 to 730 ° C.,
It can be deposited by heat treatment for 0.1 to 4 hours.
As the precipitation method, the molded glass is once cooled to room temperature and then heated to be kept at a predetermined temperature to precipitate fine particles, and the cooling process to the molding temperature or the glass after molding is cooled to room temperature. There is a method of precipitating fine particles by maintaining a predetermined temperature in the process or controlling a cooling rate, and either method is preferable.

In the method for producing an ultraviolet sharp cut glass according to the present invention, it is essentially difficult for the glass to undergo phase separation or coloring even during the cooling process from the melt state.
Various methods such as a pressing method, a roll-out method, a float method, and a Danner method, and glass molding of a predetermined shape in an atmosphere are possible.

[0041]

【Example】

(Examples 1 to 11) Raw materials were blended so as to obtain 500 g of the glass having the composition shown in Table 1, which was placed in a platinum crucible and melted at 1550 ° C for 2 hours, and then poured onto a stainless steel plate to obtain a plate-shaped glass. Molded. The temperature of this molded glass shown in Table 1,
Fine particles were deposited in the glass by performing heat treatment for a period of time. While observing the appearance of this fine particle-deposited glass, it was polished to a thickness of 1 mm, the spectral transmittance was measured, and the wavelength showing 1% transmittance and the wavelength inclination width at which the transmittance changed from 80% to 10% were obtained. It was The particle size of the fine particles in the glass was measured by observation with a transmission electron microscope. In addition, 1
250 ~ 380nm using 00W ultra high pressure mercury lamp as light source
The glass was placed at a position where the ultraviolet intensity of the above was 150 mW / cm ² and the change in transmittance ΔT% after 100 hours of exposure was measured. ΔT% was calculated by the following formula.

ΔT% = T% (transmittance before exposure at a wavelength of 430 nm) -T% (transmittance after exposure at a wavelength of 430 nm) The appearance of glass and other measured values are shown in Table 1.

(Comparative Examples 1 to 8) Glasses having the compositions shown in Table 2 were prepared in the same manner as in the examples, the appearance was observed, and the ultraviolet exposure test similar to the examples was conducted. As a result, a large change in transmittance was observed by UV irradiation.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

EFFECTS OF THE INVENTION According to the present invention, a colorless and transparent UV sharp cut glass for a high brightness light source, which is excellent in solarization resistance to high brightness UV, is manufactured.

Claims (2)

[Claims] 1. In terms of mol%, copper oxide is converted to CuO 0.01 to 2% Cl + Br 0.01 to 2% Tin and antimony oxides are converted to SnO and Sb ₂ O ₃ , respectively, and SnO + Sb ₂ Prepare an elementary glass containing 0.01 to 3% of O ₃ and heat treat the elementary glass to Cu.
In the production of UV sharp cut glass for high-brightness light sources by precipitating Cl or / and CuBr fine particles, the raw glass contains 0.001 to 5 mol% of at least one oxide selected from iron, lead, cerium, titanium and bismuth. A method for producing an ultraviolet sharp-cut glass for a high-brightness light source containing. 2. The base glass contains bismuth oxide in an amount of 0.1 to
The method for producing an ultraviolet sharp cut glass for a high-intensity light source according to claim 1, which contains 3 mol%.