JP2006199587A - Colored glass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide colored glass which is freed of the nickel sulfide stone or reduced in the content of the stone without spoiling design and productivity. <P>SOLUTION: The colored glass contains total iron oxides (T-Fe<SB>2</SB>O<SB>3</SB>) in terms of Fe<SB>2</SB>O<SB>3</SB>of 0.5-4 wt.% and molybdenum in terms of Mo of 0.0002 wt.% or more and less than 0.01 wt.%. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention is a colored glass containing total iron oxide (T-Fe ₂ O ₃ ) converted to at least 0.5% Fe ₂ O ₃ , particularly a colored glass that is strengthened by air cooling and used for architectural or automobile windows. In glass, the present invention relates to a colored glass in which nickel sulfide (NiS) appearing in glass is removed or reduced without impairing design and productivity.

  Nickel sulfide stone rarely occurs in glass. The particle size varies from a small one of several tens of μm to a one of several hundred μm that can be recognized with the naked eye, but these nickel sulfide stones are known to significantly impair the reliability (quality) of glass products. .

  That is, the glass is heated to a temperature near the softening point, and then the surface of the glass is generally quenched with air, thereby forming a strong compressive stress layer on the glass surface and a tensile stress layer inside. In air-cooled tempered glass with improved glass strength, serious problems are often caused when nickel sulfide stones are present in the glass.

  Nickel sulfide is known to cause a phase transition in a temperature range lower than the softening point of glass. When heated to a temperature near the softening point of the glass during air-cooling strengthening, the nickel sulfide stone transforms into a high-temperature stable phase (α-phase) and remains in the α-phase after cooling to room temperature. To do. Thereafter, as time passes, the phase gradually transitions to the room temperature stable phase (β phase). Since the phase transition from the α phase to the β phase of nickel sulfide stone involves a large volume change, strong local stress is generated around the nickel sulfide stone and sometimes cracks are generated. When the tensile stress layer existing in the glass is reached, the glass instantaneously breaks.

  Usually, it takes a long time from the strengthening of the glass containing nickel sulfide stones to the destruction caused by the phase transition of the nickel sulfide stones. It is very important not to provide it as an automobile window or the like so as not to impair the reliability of the product and the glass manufacturer.

The first step in preventing the formation of nickel sulfide stones is to not put a nickel source in the glass melting furnace. However, it is quite difficult to avoid mixing of very small amounts of nickel impurities. This is because the end material of the welding rod used in the construction and the stainless steel parts used in the mechanical equipment may cause nickel impurities. In some cases, nickel oxide is intentionally added as a coloring material for glass. In any case, it is generally difficult to completely remove the mixing of nickel impurities.
Thus, several methods have been devised so far that nickel sulfide stones are not generated even if nickel-based impurities are mixed.

  For example, in U.S. Pat. No. 4,919,698, the occurrence of nickel sulfide stones in glass is reduced by electrically oxidizing the area near the bottom of the melting furnace and at least the area between the inlet and the spring zone of the furnace. Is disclosed.

  Further, in JP-A-7-144922, a substance selected from the group consisting essentially of molybdenum, arsenic, antimony, bismuth, copper, silver, potassium dichromate, chromite iron, and combinations thereof as the crude batch substance A method for reducing the formation of nickel sulfide stones by adding at least 0.010% by weight is disclosed.

  Further, in JP-A-9-169537, a nickel-based compound contained in a glass raw material and / or a nickel-based compound mixed in the melting process of the glass raw material is produced in a melt-formed glass. A method for producing soda-lime glass characterized by suppressing nickel sulfide by adding a small amount of a zinc compound to the glass raw material is disclosed.

  The method for reducing the generation of nickel sulfide stone disclosed in the aforementioned U.S. Pat. No. 4,919,698 significantly limits the structure and operating conditions of the furnace, particularly in heat ray absorbing glass that requires measures against nickel sulfide. However, there is a problem that this method cannot be used because the inside of the furnace needs to be reduced to contain a sufficient amount of divalent iron ions exhibiting heat-absorbing ability in the glass.

  The method for reducing the formation of nickel sulfide stone disclosed in JP-A-7-144922 is also described in the text, but the addition of molybdenum, copper, iron dichromate and chromite iron There was a problem of changing the glass color tone. These colorings cannot be overlooked especially when the design is emphasized, such as automotive window glass. In addition, arsenic and antimony can not be used for float glass manufacturing because the atmosphere in the bath is contaminated by volatilization in the float bath. On the other hand, bismuth and silver are very expensive, so it is assumed that they are mass-produced. It is unsuitable to use for the production of float glass to increase the cost.

  Further, the method for reducing the formation of nickel sulfide stone disclosed in JP-A-9-169537 is characterized by suppressing nickel sulfide by adding a small amount of a zinc compound to a glass raw material. Zinc added to the float bath is significantly volatilized in the float bath, contaminating the atmosphere in the float bath, zinc oxide falling from the ceiling of the float bath, degrading the glass quality and reducing the yield was there.

The present invention has been made in view of the above-mentioned problems of the prior art, and is nickel sulfide (NiS) that appears in glass particularly in colored glass that is tempered by air cooling and used for architectural or automobile windows. In order to remove or reduce the amount, all iron oxide converted to 0.5% to 4% Fe ₂ O ₃ and molybdenum converted to 0.0002% or more and less than 0.01% Mo are included. -It aims at providing the colored glass which removed or reduced the nickel sulfide stone without impairing productivity.

The colored glass of the present invention is expressed in weight%,
Total iron oxide (T-Fe ₂ O ₃ ) converted to 0.5% to 4% Fe ₂ O ₃ , and
It is a colored glass characterized by containing molybdenum converted to Mo of 0.0002% or more and less than 0.01%.

Here, the basic glass composition of the colored glass is expressed in weight%,
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
And 0 to 5% B ₂ O ₃ .

Further, the colored glass is expressed in weight%,
Total iron oxide (T-Fe ₂ O ₃ ) converted to 0.5% to 2.2% Fe ₂ O ₃ ,
Molybdenum converted to 0.0002% or more and less than 0.01% Mo;
_{TiO 2, CeO 2, NiO,} CoO, Se, MnO, to contain the _{Cr 2 O 3, V 2 O} 5, Nd 2 O 3 and Er ₂ at least one selected from the group consisting of O ₃ in the coloring components preferable.

Also, one of the preferred forms of the colored glass is expressed in weight%,
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
And a basic glass composition consisting of 0-5% B ₂ O ₃ ;
As a coloring component,
0.5 to 2.2% of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3),
0.01% to 1.0% of TiO _2,
And 0.1-2.0% CeO ₂ ,
Furthermore, to suppress the formation of nickel sulfide stones,
A colored glass containing molybdenum converted to 0.0002% or more and less than 0.01% Mo is preferable.

Also, another preferred form of the colored glass is expressed in weight%,
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
And a basic glass composition consisting of 0-5% B ₂ O ₃ ;
As a coloring component,
0.5 to 2.2% of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3),
0-0.2% NiO,
And 0.003-0.04% CoO,
Further, it is preferably a colored glass comprising molybdenum converted to 0.0002% or more and less than 0.01% Mo in order to suppress the formation of nickel sulfide stones.

Also, another preferred form of the colored glass is expressed in weight%,
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
And a basic glass composition consisting of 0-5% B ₂ O ₃ ;
As a coloring component,
0.5 to 2.2% of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3),
0-0.2% NiO,
0.003-0.04% CoO
Contains 0.0001-0.004% Se,
Furthermore, it is preferable that the colored glass comprises molybdenum converted into Mo in an amount of 0.0002% or more and less than 0.01% in order to suppress the formation of nickel sulfide stone.

  Hereinafter, embodiments of the present invention will be described in detail.

  First, the reason for limiting the colored glass composition that suppresses the formation of the nickel sulfide stone of the present invention will be described. However, the following composition is expressed by weight%.

Iron oxide exists in the state of Fe ₂ O ₃ and FeO in glass. In the optical characteristics of glass, Fe ₂ O ₃ is a component that enhances the ability to absorb ultraviolet rays, and FeO is a component that enhances the ability to absorb heat rays. Iron oxide also has a function of suppressing the formation of nickel sulfide together with molybdenum.

Fe ₂ total iron oxide in terms of _{O 3 (T-Fe 2 O} 3) is small the effect of absorbing ultraviolet and infrared rays is less than 0.5%, not obtained the desired optical properties. On the other hand, if there is too much T-Fe ₂ O ₃ , the heat ray absorbing effect of ferrous oxide may cause the temperature of the melting tank ceiling to become higher than the heat resistant temperature during melting due to its radiant heat, which is not preferable. Furthermore, considering the case of performing continuous production in a glass melting furnace, since it takes T-Fe ₂ O ₃ time reformulation with different composition the glass base material and is too large, T-Fe ₂ O ₃ amount 4 % Or less is preferable, and 2.2% or less is more preferable.

  Molybdenum is a component for suppressing the formation of nickel sulfide stone and is an essential component of the present invention. By adding a small amount of molybdenum together with iron oxide into the colored glass, the production of nickel sulfide can be suppressed without affecting the glass color tone.

  The reason is not clear, but in the glass composition that contains both iron and molybdenum as in the present invention, the suppression effect that exceeds the effect of suppressing the formation of nickel sulfide stones that would be expected when present alone. Was found to be obtained. This is considered to be an effect caused by some kind of interaction between iron and molybdenum, for example.

  If the amount of molybdenum is less than 0.0002% in terms of Mo, a sufficient effect cannot be obtained, and addition of 0.01% or more affects the glass color tone. The color of the glass colored with molybdenum is tinged with yellowish brown color, and it is not preferable because the color tone is remarkably impaired in design as if the cigarette dust has adhered. Moreover, a large amount of addition increases the manufacturing cost of glass, and is unpreferable.

TiO ₂ , CeO ₂ and V ₂ O ₅ are coloring components that impart ultraviolet absorbing ability to glass. NiO, CoO, Se, MnO, Cr ₂ O ₃ , Nd ₂ O ₃ and Er ₂ O ₃ are added singly or in combination to mainly adjust the visible light transmittance and give a desired color tone to the glass. can do. Preferred combinations for obtaining a specific color tone are shown below.

For example, in the case of a glass having a green color tone with a visible light transmittance (YA) measured using an A light source as high as 70% or more, in addition to 0.5 to 2.2% of T-Fe ₂ O ₃ , 0 It is preferably composed of a combination of 0.01-1.0% TiO ₂ and 0.1-2.0% CeO ₂ .

In addition, in order to obtain a grayish green color tone, in addition to 0.5 to 2.2% T-Fe ₂ O ₃ , 0 to 0.2% NiO and 0.003 to 0.005. It preferably consists of a combination of 04% CoO.

Moreover, in order to obtain a gray color tone having low stimulation purity, in addition to 0.5 to 2.2% T-Fe ₂ O ₃ , 0 to 0.2% NiO, 0.003 to 0.04% Preferably, it consists of a combination of CoO and 0.0001-0.004% Se.

  The colored glass of the present invention is preferably produced by a float process, but is not necessarily limited thereto. The reason for limiting the preferred basic glass composition will be described in detail below. The following composition is expressed in weight%.

SiO ₂ (silica) is a main component that forms a glass skeleton. If the SiO ₂ content is less than 65%, the durability of the glass decreases. If it exceeds 80%, it becomes difficult to melt the glass.

Al ₂ O ₃ is a component that improves the durability of the glass, but if it exceeds 5%, it becomes difficult to melt the glass. A preferable range of Al ₂ O ₃ is 0.1 to 2%.

  MgO and CaO are used to improve the durability of the glass and adjust the devitrification temperature and viscosity during molding. When MgO exceeds 10%, the devitrification temperature rises. When CaO is less than 5% or exceeds 15%, the devitrification temperature increases. If the total of MgO and CaO is less than 5%, the durability of the glass is lowered, and if it exceeds 15%, the devitrification temperature is increased.

Na ₂ O and K ₂ O promote glass melting. When Na ₂ O is less than 10% or the total of Na ₂ O and K ₂ O is less than 10%, the dissolution promoting effect is poor, and Na ₂ O exceeds 18% or the total of Na ₂ O and K ₂ O is If it exceeds 20%, the durability of the glass will decrease. If the amount of K ₂ O is large, the cost becomes high, so it is desirable to keep K ₂ O at 5% or less.

B ₂ O ₃ is a component used to improve the durability of the glass or as a dissolution aid, but also has a function of enhancing the absorption of ultraviolet rays. If B ₂ O ₃ exceeds 5%, inconvenience at the time of molding due to volatilization or the like occurs, so 5% is made the upper limit.

The glass composition range of the present invention, in the range of 0 to 1% in a total amount of SnO ₂ as a fining agent or the reducing agent, the present invention may be added within a range not to impair the color tone of interest.

  Hereinafter, embodiments of the present invention will be described with specific examples.

Examples 1-7, Comparative Examples 1-4
Add the required amount of molybdenum trioxide, ferric oxide, titanium oxide, cerium oxide, cobalt oxide, metal selenium, nickel oxide, chromium oxide, neodymium oxide and erbium oxide to typical soda-lime silica glass batch components At the same time, a carbon-based reducing agent (specifically, coke powder or the like), a clarifying agent, and a metal nickel powder equivalent to 0.035% for promoting the formation of nickel sulfide stone were added and mixed. This raw material was put in an alumina crucible having a capacity of 250 cc, heated to 1400 ° C. in an electric furnace and melted for 2 hours and 20 minutes, and then a glass substrate was poured on a stainless steel plate and gradually cooled to room temperature to obtain a glass plate. . The number and size of the nickel sulfide stones present in the glass were measured on the obtained glass plate by microscopic observation.

Table 1 shows the basic glass composition of the obtained sample. Tables 2 and 3 show the T-Fe ₂ O ₃ concentration, FeO (Fe ₂ O ₃ conversion) / T-Fe ₂ O ₃ ratio (% by weight), TiO ₂ concentration, CeO ₂ concentration, CoO of each sample. The concentration, NiO concentration, Se concentration, and Mo concentration, the number of nickel sulfide stones (NiS), the maximum diameter (μm), and the number of NiS per glass weight (pieces / g) of each sample are shown. The numbers indicating the concentrations in Tables 1 to 3 are expressed in weight%, but the CoO concentration, NiO concentration, Se concentration, and Mo concentration are expressed in ppm. Further, the SiO ₂ concentration in Table 1 is not displayed decimal place is, this is because the rounded off following SiO ₂ decimal.

(Table 1)
Basic glass composition (wt%)
SiO ₂ 71
Al ₂ O ₃ 1.6
MgO 3.6
CaO 7.7
Na ₂ O 13.7
K ₂ O 0.9

(Table 2)
----------------------------------
Example 1 Example 2 Example 3 Example 4
----------------------------------
T-Fe ₂ O ₃ (wt%) 1.00 0.65 1.25 1.24
FeO / T-Fe ₂ O ₃ (%) 23 26 23 24
TiO ₂ (wt%) 0.03 0.15 0.03 0.03
CeO ₂ (wt%) 1.00 1.65 0 0
CoO (ppm) 0 2 180 190
NiO (ppm) 0 0 690 660
Se (ppm) 0 0 0 14
Mo (ppm) 7 11 20 60
----------------------------------
Number of NiS (pieces) 26 32 12 3
Maximum diameter (μm) 250 300 200 260
Number of NiS (pieces / g) 0.17 0.20 0.097 0.019
----------------------------------












----------------------------------
Example 5 Example 6 Example 7
----------------------------------
T-Fe ₂ O ₃ (wt%) 2.00 1.30 3.1
FeO / T-Fe ₂ O ₃ (%) 24 23 24
TiO ₂ (wt%) 0.05 0.03 0.03
CeO ₂ (wt%) 0 0 0
Nd ₂ O ₃ (wt%) 1.0 0 0
CoO (ppm) 0 180 0
NiO (ppm) 0 1000 0
Se (ppm) 0 0 0
Mo (ppm) 3 20 70
----------------------------------
Number of NiS (pieces) 19 16 0 (NiS not allowed)
Maximum diameter (μm) 240 320 0
Number of NiS (pieces / g) 0.13 0.089 0
----------------------------------

(Table 3)
----------------------------------
Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4
----------------------------------
T-Fe ₂ O ₃ (wt%) 0.12 0.65 0.12 0.12
FeO / T-Fe ₂ O ₃ (%) 22 26 22 26
TiO ₂ (wt%) 0.03 0.13 0.03 0.13
CeO ₂ (wt%) 0 1.65 0 0
CoO (ppm) 0 0 0 0
NiO (ppm) 0 0 0 0
Se (ppm) 0 0 0 0
Mo (ppm) 0 0 75 11
----------------------------------
Number of NiS (pieces) 65 45 58 63
Maximum diameter (μm) 180 240 200 200
Number of NiS (pieces / g) 0.49 0.29 0.26 0.41
----------------------------------

  Examples 1-7 are compositions within the scope of claim 1. As is apparent from Table 1, all of Examples 1-7 are in the preferred range of basic glass composition indicated in claim 2. Comparative Example 1 has a typical soda-lime-silica glass composition, but it can be seen that the present invention has an effect of removing or reducing nickel sulfide by comparing the number of NiS in Comparative Example 1 with this example.

  Moreover, Examples 1-6 are the composition within the range of Claim 3 which is a preferable range, and it turns out that it is a colored glass which removed or reduced nickel sulfide from Table 2. Of these, Examples 1 to 4 and 6 are compositions having excellent design properties, which are particularly suitable for architectural or automotive window glass, and the characteristics thereof will be described below.

  Examples 1 and 2 are compositions within the preferred range of Claim 4. These Examples 1 and 2 are colored glasses having a high visible light transmittance of 70% or more measured using the A light source and having a green color tone. As is clear from Table 2, nickel sulfide was removed or reduced. It turns out that it is colored glass. In addition, it can be seen from the comparison between Example 2 and Comparative Examples 2 and 3 that an excellent nickel sulfide reduction effect can be obtained when iron and molybdenum are simultaneously contained.

  Examples 3 and 6 are compositions within the range of claim 5, which is a preferred range. These examples are colored glass having a grayish green color (grayish green), and as is clear from Table 2, it can be seen that the colored glass has nickel sulfide removed or reduced.

  Example 4 is a composition within the range of claim 6 which is a preferred range. This Example 4 is a colored glass having a gray color tone with low stimulation purity, and as can be seen from Table 2, it can be seen that this is a colored glass from which nickel sulfide has been removed or reduced.

Comparative Example 1 is a typical soda-lime-silica glass composition, and both T-Fe ₂ O ₃ and molybdenum amounts are out of the scope of the present invention. If the number of NiS production | generations in this composition is seen, the NiS production | generation suppression effect in this invention is clear. In Comparative Example 2, only T-Fe ₂ O ₃ has a composition within the scope of the present invention, while Comparative Examples 3 and 4 have a molybdenum content within the scope of the present invention. It turns out that all are inferior to the NiS production | generation suppression effect compared with the Example of this invention.

  As described above in detail, according to the present invention, a colored glass from which nickel sulfide stones are removed or reduced without impairing design and productivity is provided.

Claims (6)

Displayed in weight%
Total iron oxide (T-Fe ₂ O ₃ ) converted to 0.5% to 4% Fe ₂ O ₃ , and
A colored glass comprising molybdenum converted to Mo in an amount of 0.0002% or more and less than 0.01%. The basic glass composition is expressed in weight%,
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
The colored glass according to claim 1, comprising 0 to 5% of B ₂ O ₃ . Displayed in weight%
Total iron oxide (T-Fe ₂ O ₃ ) converted to 0.5% to 2.2% Fe ₂ O ₃ ,
Molybdenum converted to 0.0002% or more and less than 0.01% Mo;
Containing at least one coloring component selected from the group consisting of TiO ₂ , CeO ₂ , NiO, CoO, Se, MnO, Cr ₂ O ₃ , V ₂ O ₅ , Nd ₂ O ₃ and Er ₂ O _3. The colored glass according to claim 1 or 2, characterized by the above. Displayed in weight%
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
And a basic glass composition consisting of 0-5% B ₂ O ₃ ;
As a coloring component,
0.5 to 2.2% of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3),
0.01% to 1.0% of TiO _2,
And 0.1-2.0% CeO ₂ ,
Furthermore,
The colored glass according to any one of claims 1 to 3, comprising molybdenum converted to 0.0002% or more and less than 0.01% Mo. Displayed in weight%
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
And a basic glass composition consisting of 0-5% B ₂ O ₃ ;
As a coloring component,
0.5 to 2.2% of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3),
0-0.2% NiO,
And 0.003-0.04% CoO,
Furthermore,
The colored glass according to any one of claims 1 to 3, comprising molybdenum converted to 0.0002% or more and less than 0.01% Mo. Displayed in weight%
65% to 80% of SiO _2,
0 to 5% Al ₂ O _3,
0-10% MgO,
5-15% CaO,
5-15% MgO + CaO,
10-18% Na ₂ O,
0-5% K ₂ O,
10-20% Na ₂ O + K ₂ O,
And a basic glass composition consisting of 0-5% B ₂ O ₃ ;
As a coloring component,
0.5 to 2.2% of the total iron oxide in terms of _{Fe 2 O 3 (T-Fe} 2 O 3),
0-0.2% NiO,
0.003 to 0.04% CoO,
And 0.0001-0.004% Se,
Furthermore,
The colored glass according to any one of claims 1 to 3, comprising molybdenum converted to 0.0002% or more and less than 0.01% Mo.