JP2001180966A - Manufacturing method of deeply colored glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of deeply colored glass which enables to heat and fuse easily the whole layer of the colored glass and controls the glass to become less uneven in quality and color as much as possible. SOLUTION: The deeply colored glass, containing Fe2O3 (hematite) at 0.3% or more as a coloring component for soda-lime silica type glass, is manufactured by adding Li2O at 0.01-0.5% into the soda-lime silica type glass comprising SiO2-Al2O3-MgO-CaO-Na2O-K2O as basic components.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a densely colored glass having a relatively low visible light transmittance, which has both solar radiation absorbing performance and ultraviolet absorbing performance, and has an appropriate transparency and privacy. And deep colored glass useful as window glass for transportation equipment such as automobiles, ships, and aircraft.

[0002]

2. Description of the Related Art In recent years, dark gray, dark green, dark bronze colored glasses containing various coloring components including Fe ₂ O ₃ in soda-lime-silica glass have low visible light transmittance. Various types of deep-colored glass are provided on the market as various window materials. Since these deeply colored glasses are highly heat-absorbing, it is not easy to heat and melt the lower layer of the glass layer by heating from the upper layer of the glass layer by burning heavy oil in a normal glass kiln. Even if the glass is made to be inhomogeneous, unevenness and color unevenness of the glass occur, and the production efficiency and production efficiency are remarkably inferior to those in the case of producing a colorless and transparent glass. Alternatively, there are cases in which an auxiliary heating device is used in combination to heat the lower layer of the glass layer, and the production efficiency and production efficiency can be improved to some extent. Rising is also unavoidable.

[0003] For example, JP-A-8-165136 discloses that SiO ₂ , Al ₂ O ₃ , MgO, CaO, Na ₂ O, K
A neutral gray glass composition comprising soda-lime-silica-based glass composed of ₂ O and having a specific content range of Fe ₂ O ₃ (0.8 to 1.2 wt%), TiO ₂ , CoO, and Se is disclosed. ₂ O, B
It is described that ₂ O ₃ , BaO, etc. can be contained in a range of 2 wt% or less, but the purpose and effect are not mentioned.

[0004] It is an object of the present invention to provide a deeply colored glass in which the lower layer of the glass layer is easily heated and melted by an easy means, and the occurrence of unevenness and color unevenness of the glass is suppressed as much as possible.

[0005]

SUMMARY OF THE INVENTION The present invention provides a soda-lime-silica-based glass as a coloring component in terms of mass percentage of Fe.
A glass containing 0.3% or more of ₂ O ₃ (total iron), wherein the soda-lime-silica glass is SiO ₂ —Al ₂ O ₃ —MgO—CaO—Na
A base component consisting of ₂ O-K ₂ O is a dark colored glass, characterized in that the introduction of Li ₂ O 0.01~0.5%.

Basic components of the soda-lime-silica glass
Is SiO in mass percentage (%)_Two68-73, Al_TwoO_Three0 to
3, MgO 0-5, CaO 5-12, Na_TwoO 10-15, K_TwoO 0
3, Li _TwoO is included in the range of 0.1 to 0.5.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the basic component composition of the soda-lime-silica glass of the present invention, the content of SiO ₂ is 68 to 73.
%. SiO ₂ is important as a skeleton forming component of glass, and if it is less than 68%, the glass becomes unstable and devitrification tends to occur. In addition, the durability of the glass decreases. 73
%, The glass tends to be difficult to melt.
Al ₂ O ₃ improves the chemical resistance of the glass and improves the moldability of the glass, and is contained in the glass in the range of 0 to 3%. If it exceeds 3%, glass melting tends to be difficult. Preferably, it is contained in the glass in the range of 1 to 3%.

[0008] MgO is eutectic with SiO ₂ and Al ₂ O ₃ to facilitate melting of the glass and to reduce the viscosity of the glass to facilitate molding. The MgO is contained in the glass in the range of 0 to 5%. When the content exceeds 5%, the heat resistance of the glass is deteriorated and devitrification tends to occur. More preferably, it is contained in the range of 1 to 5%. CaO is also a eutectic component with SiO ₂ or Al ₂ O _3, and is a suitable component for facilitating glass melting, lowering glass viscosity and facilitating molding. , In glass in the range of 5 to 12%. If it is less than 5%, the above effect is insufficient, and if it exceeds 12%, the heat resistance of the glass is degraded and devitrification tends to occur.

Na ₂ O is an important component in reacting with SiO ₂ and Al ₂ O ₃ and melting them, and is contained in the glass in the range of 10 to 15%. If it is less than 10% in the glass, the above effect is insufficient, and if it exceeds 15%, the tendency of devitrification increases, thereby deteriorating the heat resistance of the glass and deteriorating the weather resistance and water resistance of the glass. K ₂ O reacts with SiO ₂ and Al ₂ O ₃ similarly to Na ₂ O and melts them, so that it is added to Na ₂ O and contained in the glass. If it exceeds 3%, the tendency of devitrification increases, and the heat resistance of the glass deteriorates, and the weather resistance and water resistance of the glass deteriorate.

Li ₂ O is an important component for greatly reducing the viscosity of the glass, thus facilitating the convection of the glass melt and promoting the melting and homogenization of the glass. As described above, Fe ₂ O ₃ (all iron) is used as a coloring component in soda-lime glass.
When the content is 0.3% or more, the colored glass is rich in heat ray absorption, so that the heating and melting of the lower layer of the glass layer is not easy in the heating method from the upper layer of the glass layer by burning heavy oil in a normal glass furnace, and the amount of drawn glass is suppressed. Even if such measures are taken, inhomogeneity and color unevenness of the glass occur, and the production efficiency and production efficiency are remarkably inferior to those in the case of producing colorless and transparent glass. On the other hand, by incorporating Li ₂ O into the glass, the viscosity of the glass is greatly reduced, and therefore, the convection of the glass melt is facilitated, and the melting and homogenization of the glass are promoted.

Li ₂ O is contained in the glass in the range of 0.01 to 0.5%. If it is less than 0.01%, the effect of promoting the melting and homogenization of the glass is insufficient, and if it exceeds 0.5%, it is lost. The permeability tends to increase, deteriorating the heat resistance of the glass. Preferably, it is in the range of 0.1 to 0.5%.

In the present invention, Fe ₂ O in soda-lime glass is used.
_The present invention can be applied to all glass compositions containing 0.3% or more of ₃ (total iron), and can be suitably used, for example, in the following examples filed by the present applicant.

[0013] That is, in JP-A 6-247740 discloses according to the applicant's application, as a coloring component in soda-lime-silica glass, in wt% display, Fe ₂ O ₃ (total iron) 0.
45 ~ 0.75, FeO 0.08 ~ 0.30, Se 0.0010 ~ 0.0060, CoO
_{0.0140~0.0250, Cr 2 O 3 0~0.0300,} Ni0 0~0.0350, Ti
Incorporated within a range of O ₂ 0-0.70, but neutral gray system color glass main wavelength of 490~575nm is disclosed, employing the glass composition of the present invention as a basis composition of the soda-lime-silica glass can do.

[0014] Further, Japanese Patent Application No. Hei 11
In the specification of 192942, as a coloring component in soda-lime-silica-based glass, Fe ₂ O ₃ (total iron) 0.3 to
0.8, FeO 0.06-0.18, CoO 0.0050- <0.0140, Cr ₂ O ₃
0.0030 to 0.0200, Se 0.0005 to 0.0025, and the ratio of divalent iron ions to total iron ions (Fe ²⁺
/ (Fe ²⁺ + Fe ³⁺ )) is in the range of 0.2 to 0.3, the visible light transmittance at a glass plate thickness of 3.5 mm is 35 to 55%, the solar transmittance is 35 to 60%, and the ultraviolet transmittance is 25%. Hereafter, however, visible light transmittance ≦ solar transmittance, and the main wavelength of the light source D is
A dark gray glass having an optical property of 480 to 580 nm and an excitation purity of 4% or less is described. Further, Japanese Patent Application No. 11-151962 discloses, as a coloring component in soda-lime-silica-based glass, wt%. , Fe ₂ O ₃ (total iron) 0.6-1.0, FeO 0.
10 to 0.23, Fe ²⁺ / (Fe ^{2 +} + Fe ³⁺ ) ion ratio 0.18 to 0.32, C
oO 0.010-0.030, Cr ₂ O ₃ 0.030-0.065, Se 0.0005-0.
0030, and the dominant wavelength due to the D light source is 485.
A dark green colored glass that is ~ 520 nm is described,
It is described that the UV transmittance at a plate thickness of 5 mm is 15% or less, the visible light transmittance is 10 to 35%, the solar transmittance is 15 to 35%, and the stimulus purity by the D light source is 4.0 to 15.0%. or the Pat Hei 11-192943, as a coloring component in soda-lime-silica based glass in wt% display, Fe ₂ O ₃ (total iron) is 0.7 to 1.6, FeO is 0.10 to 0.23 (however iron Ratio of ferrous ions in the ions: Fe ²⁺ / (Fe ²⁺ + F
e3 ⁺ ) is 0.10 ~ 0.20), CoO is 0.010 ~ 0.030, NiO is 0.010
-0.100, Se is contained in the range of 0 to 0.0008, and a deep green glass having a dominant wavelength of 485 to 530 nm according to a D light source is described. The ultraviolet transmittance at a plate thickness of 5 mm is 15% or less. Visible light transmittance 10 ~ 35%, solar transmittance
It is described that the stimulus purity by the D light source is 5 to 15%, and the glass composition of the present invention can be applied to any of those glasses as a basic component composition.

[0015]

Embodiments of the present invention will be described below.

[Comparative Example 1 Preparation of raw material for sample] A small amount of mirabilite and slag for clarification were added to a mixture of silica sand, feldspar, soda ash, dolomite, and limestone as raw materials for the basic component, and the following target basic component composition was obtained. In addition, asphalt, cobalt oxide, and chromium oxide were blended as coloring component raw materials, and all raw materials were prepared with the following target coloring component compositions.

Basic component composition SiO ₂ 70.4 (%) Al ₂ O ₃ 1.9 MgO 3.5 CaO 9.0 Na ₂ O 13.7 K ₂ O 0.7 Li ₂ O 0 Total 99.2 Coloring component composition Fe ₂ O ₃ (total iron) 0.75 (%) CoO 0.025 Cr ₂ O ₃ 0.025 Se 0.004 Total 0.804 The above composition is visible light transmittance at a glass thickness of 3 mm.
It is applied as a 20% privacy glass and a solar shading glass.

Examples 1-3 Preparation of Sample Raw Materials Example 1: Na ₂ O in the basic component was 0.1
%, To 13.6%, 0.1% of Li ₂ O (using lithium carbonate as a raw material) was introduced, and the mixture was blended and prepared in exactly the same manner as Comparative Example 1 including the coloring components.

Example 2: Na ₂ O in the basic component was reduced by 0.2% compared to Comparative Example 1 to 13.5%, and Li ₂ O (using lithium carbonate as a raw material) was introduced at 0.2%. The compound was prepared and prepared in exactly the same manner as in Comparative Example 1.

Example 3: Na ₂ O in the basic component was reduced by 0.3% compared to Comparative Example 1 to 13.4%, and 0.3% of Li ₂ O (using lithium carbonate as a raw material) was introduced. The compound was prepared and prepared in exactly the same manner as in Comparative Example 1.

[Glass Melting] An electric furnace which was filled with approximately 1 L of each raw material mixture in a vertically long cylindrical ceramic crucible and provided with resistance heaters on the ceiling and side walls of the furnace and heated to about 1450 ° C. And melted for 4 hours, and then allowed to cool in the furnace to remove the crucible.

[Test Method and Results] Each glass was cut together with the crucible to prepare a plate-like thin sample of a longitudinal section of the glass including the center line of the crucible. Further, both surfaces of the sample were polished to observe the remaining state of bubbles based on the decomposition of the raw material, the state of striae based on the convection of the glass melt, and the like. Glass is seen through a white light source, and the remaining state of bubbles is large (), slightly large (), slightly small (), small (), extremely small
The striae was evaluated as (), striae were striking (), slightly strong (), slightly weak (), weak (), and extremely weak ().

With respect to the remaining glass, the crushed glass pieces were set in a temperature gradient furnace, and the devitrification temperature (° C.), the maximum devitrification growth temperature (° C.), and the maximum devitrification growth rate (μm / H) were measured.

[0024] Furthermore, for the rest of the glass, the fragments were filled in a platinum crucible and heated fluidized, platinum ball pulling method by melting temperature (glass exhibits 10 ² poise temperature:
℃), working temperature (glass exhibits 10 ⁴ poise temperature:
° C). Further, the glass is formed into a fine line shape, and a softening point (glass is 10%) is obtained by a fiber elongation method.
^7.6 Poise temperature: ° C), strain point (glass is 10 ^14.5)
Temperature at which poise is exhibited: ° C) was measured. Table 1 shows the results.

[Table 1] Example and Comparative Example Comparative Example 1 Example 1 Example 2 Example 3 (Li ₂ O%) (0) (0.1) (0.2) (0.3) ────────────────────── ────────────── Glass temperature / viscosity melting temperature (° C) 1446 1437 1428 1418 Working temperature (° C) 1044 1038 1032 1028 Softening point (° C) 730 724 717 712 Strain point (° C) 520 512 504 496 Devitrification tendency Devitrification temperature (° C) 1017 1015 1014 1009 Maximum devitrification growth temperature (° C) 970 950 940 935 Maximum devitrification growth rate (μm / H) 150 210 240 280 Cross-sectional observation (evaluation)理

As shown in the table, the melting temperature (the temperature at which the glass exhibits 10 ² poises) and the working temperature (the temperature at which the glass exhibits 10 ⁴ poises) are remarkably reduced with the amount of Li ₂ O introduced. Is melted at the same temperature, the greater the amount of Li ₂ O introduced, the greater the fluidity of the glass melt and the better the melting and homogeneity in the glass melting region to the adjustment region. In addition, the float molding temperature decreases, but it is within a range that can be adequately controlled by controlling the temperature of the tin bath.

If Li ₂ O is contained in an excessive amount, the thermal properties of the glass such as the softening point and the strain point are lowered, and the devitrification rate is significantly increased. Should be fastened.

Further, as is apparent from the cross-sectional observation, reduction of bubbles and improvement of striae are apparent in the range of this embodiment.

[0029]

According to the present invention, it is possible to facilitate the heating and melting of the entire colored glass layer by an easy means and to suppress the occurrence of unevenness and uneven color of the glass as much as possible.

Continued on front page F-term (reference) 4G062 AA01 BB01 BB03 DA06 DA07 DB01 DB02 DB03 DC01 DD01 DE01 DF01 EA02 EB04 EC01 EC02 EC03 ED01 ED02 ED03 EE03 EE04 EF01 EG01 FA01 FA10 FB01 FC01 FD01 FG01 GD01 GE01 HH01 HH03 HH05 HH07 HH09 HH11 HH12 HH13 HH15 HH17 JJ01 JJ03 JJ05 JJ07 JJ10 KK01 KK03 KK05 KK07 KK10 MM01 NN05 NN07 NN13

Claims (2)

[Claims] 1. A glass containing 0.3% or more by mass of Fe ₂ O ₃ (total iron) as a coloring component in a soda-lime-silica glass,
Dark colored glass, characterized in that the introduction of Li ₂ O 0.01 to 0.5% to the base component consisting _{SiO 2 -Al 2 O 3 -MgO-} CaO-Na 2 O-K 2 O. 2. The basic composition of soda-lime-silica glass.
Is SiO in mass percentage (%)_Two 68-73, Al_TwoO_Three0 to
3, MgO 0-5, CaO 5-12, Na_TwoO 10-15, K_TwoO 0
3, Li_TwoO characterized by being included in the range of 0.1 to 0.5
The deeply colored glass according to claim 1.