Patent Application
20230365455
The present invention relates to a glass composition and a method for producing a glass composition.
A standard solid sample that enables an analysis for a trace element has been in demand for an element analysis of a solid matter, such as an inductively coupled plasma (ICP) mass spectrometry, a secondary ion mass spectrometry (SIMS), and an X-ray fluorescence (XRF) analysis.
A first aspect of the present invention is a glass composition including, as main content components, by mass %, a TeO2 content percentage of 50% to 80%, a Bi2O3 content percentage of 0% to 30%, a WO3 content percentage of 0% to 30%, a ZnO content percentage of 0% to 30%, a BaO content percentage of 0% to 30%, a GeO2 content percentage of 0% to 30%, and a Ga2O3 content percentage of 0% to 30%, wherein at least any one of additive target elements is introduced, the additive target elements including, Si4+ of 1 mg/kg to 1,500 mg/kg, B3+ of 1 mg/kg to 1,500 mg/kg, P5+ of 1 mg/kg to 1,500 mg/kg, Li+ of 1 mg/kg to 1,500 mg/kg, Na+ of 1 mg/kg to 1,500 mg/kg, K+ of 1 mg/kg to 1,500 mg/kg, Mg2+ of 1 mg/kg to 1,500 mg/kg, Ca2+ of 1 mg/kg to 1,500 mg/kg, Al3+ of 1 mg/kg to 1,500 mg/kg, and Sr2+ of 1 mg/kg to 1,500 mg/kg. The glass composition is a glass composition including, as main content components, by mass %, a TeO2 content percentage of 50% to 80%, a Bi2O3 content percentage of 0% to 30%, a WO3 content percentage of 0% to 30%, a ZnO content percentage of 0% to 30%, a BaO content percentage of 0% to 30%, a GeO2 content percentage of 0% to 30%, and a Ga2O3 content percentage of 0% to 30%, wherein the glass composition contains an additive target element being an element different from Te, Bi, W, Zn, Ba, Ge, and Ga, and the glass composition contains the additive target element by 1 mg/kg to 1,500 mg/kg per one element. The glass composition is a glass composition including at least any one of additive target elements being introduced to main content components, the additive target elements including Si4+ of 1 mg/kg to 1,500 mg/kg, B3+ of 1 mg/kg to 1,500 mg/kg, P5+ of 1 mg/kg to 1,500 mg/kg, Li+ of 1 mg/kg to 1,500 mg/kg, Na+ of 1 mg/kg to 1,500 mg/kg, K+ of 1 mg/kg to 1,500 mg/kg, Mg2+ of 1 mg/kg to 1,500 mg/kg, Ca2+ of 1 mg/kg to 1,500 mg/kg, Al3+ of 1 mg/kg to 1,500 mg/kg, and Sr2+ of 1 mg/kg to 1,500 mg/kg.
A second aspect of the present invention is a method for producing the glass composition described above.
Hereinafter, description is made on an embodiment of the present invention (hereinafter, referred to as the “present embodiment”). The present embodiment described below is an example for describing the present invention, and is not intended to limit the present invention to the contents described below.
A glass composition according to the present embodiment is a glass composition including, as main content components, by mass %, a TeO2 content percentage of 50% to 80%, a Bi2O3 content percentage of 0% to 30%, a WO3 content percentage of 0% to 30%, a ZnO content percentage of 0% to 30%, a BaO content percentage of 0% to 30%, a GeO2 content percentage of 0% to 30%, and a Ga2O3 content percentage of 0% to 30%, wherein at least any one of additive target elements is introduced, the additive target elements including, Si4+ of 1 mg/kg to 1,500 mg/kg, B3+ of 1 mg/kg to 1,500 mg/kg, P5+ of 1 mg/kg to 1,500 mg/kg, Li+ of 1 mg/kg to 1,500 mg/kg, Na+ of 1 mg/kg to 1,500 mg/kg, K+ of 1 mg/kg to 1,500 mg/kg, Mg2+ of 1 mg/kg to 1,500 mg/kg, Ca2+ of 1 mg/kg to 1,500 mg/kg, Al3+ of 1 mg/kg to 1,500 mg/kg, and Sr2+ of 1 mg/kg to 1,500 mg/kg.
The glass composition according to the present embodiment is a glass composition including main content components of the glass composition of, by mass %, a TeO2 content percentage of 50% to 80%, a Bi2O3 content percentage of 0% to 30%, a WO3 content percentage of 0% to 30%, a ZnO content percentage of 0% to 30%, a BaO content percentage of 0% to 30%, a GeO2 content percentage of 0% to 30%, and a Ga2O3 content percentage of 0% to 30%, wherein the glass composition contains an additive target element being an element different from Te, Bi, W, Zn, Ba, Ge, and Ga, and the glass composition contains the additive target element by 1 mg/kg to 1,500 mg/kg per one element.
The glass composition according to the present embodiment is a glass composition including at least any one of additive target elements being introduced to main content components, the additive target elements including Si4+ of 1 mg/kg to 1,500 mg/kg, B3+ of 1 mg/kg to 1,500 mg/kg, P5+ of 1 mg/kg to 1,500 mg/kg, Li+ of 1 mg/kg to 1,500 mg/kg, Na+ of 1 mg/kg to 1,500 mg/kg, K+ of 1 mg/kg to 1,500 mg/kg, Mg2+ of 1 mg/kg to 1,500 mg/kg, Ca2+ of 1 mg/kg to 1,500 mg/kg, Al3+ of 1 mg/kg to 1,500 mg/kg, and Sr2+ of 1 mg/kg to 1,500 mg/kg.
In the present specification, a content percentage of each of main content components is expressed with mass % with respect to the total glass weight in terms of an oxide-converted composition, unless otherwise stated. Assuming that oxides, complex salt, and the like, which are used as raw materials as glass constituent components are all decomposed and turned into oxides at the time of melting, the oxide-converted composition described herein is a composition in which each component contained in the glass is expressed with a total mass of the oxides as 100%. A content percentage of the additive target element is expressed as a content amount in a cation state with “mg/kg”, unless otherwise stated. “mg/kg” is used similarly to mass ppm.
The expression that a Q content percentage of “0% to N %” is an expression indicating a case in which the Q component is not contained and a case in which the Q component is contained by a percentage of N % or less excluding 0%.
The expression “devitrification resistance stability” indicates resistance of the glass with respect to devitrification. Here, “devitrification” indicates a phenomenon of losing transparency of the glass due to crystallization, phase splitting, or the like at the time of raising a temperature of the glass to a glass transition temperature or higher or at the time of reducing the temperature to a liquid phase temperature or lower from a molten state.
The glass composition according to the present embodiment has a low melting temperature and high devitrification resistance stability. In the glass composition that has hitherto been produced, an unintended element is contained by a minute amount as “impurity”. The glass composition according to the present embodiment is a glass composition containing an intended element by a minute amount while reducing a content amount of an unintended element. Thus, the glass composition may be used as a standard solid sample for a mass analysis such as an inductively coupled plasma (ICP) mass spectrometry, a secondary ion mass spectrometry (SIMS), and an X-ray fluorescence (XRF) analysis.
A component composition of the glass composition according to the present embodiment is described below.
In the present specification, the main content components indicate, for example, various oxides such as TeO2, Bi2O3, WO3, ZnO, BaO, GeO2, and Ga2O3 that are generally adopted for a glass composition, and indicate a component forming the glass composition according to the present invention before the additive target element is introduced.
TeO2 is a component that lowers a melting temperature of the glass and improves devitrification resistance stability, and is an essential component in the present invention. However, when the content percentage is excessively high, devitrification resistance stability is reduced. From such a viewpoint, the content percentage of TeO2 is 50% to 80%. A lower limit of the content percentage is preferably 55%, more preferably, 60%. An upper limit of the content percentage is preferably 75%, more preferably, 70%.
Bi2O3 is a component that can lower a melting temperature of the glass and enhance devitrification resistance stability of the glass by coexisting with TeO2. However, when the content percentage is excessively high, the content percentage of TeO2 is relatively reduced, and devitrification resistance stability is rather degraded. From such a viewpoint, the content percentage of Bi2O3 is 0% to 30%. A lower limit of the content percentage is preferably 5%, more preferably, 10%. An upper limit of the content percentage is 25%, more preferably, 20%.
WO3 is a component that can lower a melting temperature of the glass and enhance devitrification resistance stability of the glass by coexisting with TeO2. However, when the content percentage is excessively high, the content percentage of TeO2 is relatively reduced, and devitrification resistance stability is rather degraded. From such a viewpoint, the content percentage of WO3 is 0% to 30%. A lower limit of the content percentage is preferably 5%, more preferably, 10%. An upper limit of the content percentage is 25%, more preferably, 20%.
ZnO is a component that can improve devitrification resistance stability of the glass and enhance devitrification resistance stability of the glass by coexisting with TeO2. However, when an excessively high amount thereof is introduced, a melting temperature of the glass is increased. From such a viewpoint, the content percentage of ZnO is 0% to 30%. A lower limit of the content percentage is preferably 7%, more preferably, 15%. An upper limit of the content percentage is preferably 26%, more preferably, 22%.
BaO is a component that can improve devitrification resistance stability of the glass and enhance devitrification resistance stability of the glass by coexisting with TeO2. However, when an excessively high amount thereof is introduced, a melting temperature of the glass is increased. From such a viewpoint, the content percentage of BaO is 0% to 30%. A lower limit of the content percentage is preferably 7%, more preferably, 15%. An upper limit of the content percentage is preferably 26%, more preferably, 22%.
GeO2 is a component that improves devitrification resistance stability of the glass. However, when the content percentage is excessively high, a melting temperature of the glass is increased. GeO2 is also an expensive raw material. From such a viewpoint, the content percentage of GeO2 is 0% to 30%. A lower limit of the content percentage is preferably 5%, more preferably, 10%. An upper limit of the content percentage is preferably 25%, more preferably, 20%.
Ga2O3 is a component that improves devitrification resistance stability of the glass. However, when the content percentage is excessively high, a melting temperature of the glass is increased. Ga2O3 is also an expensive raw material. From such a viewpoint, the content percentage of Ga2O3 is 0% to 30%. A lower limit of the content percentage is preferably 5%, more preferably, 10%. An upper limit of the content percentage is preferably 25%, more preferably, 20%.
Stable glass cannot be formed with TeO2 alone. However, stable glass with high devitrification resistance stability can be obtained by coexisting with a certain amount of Bi2O3, WO3, ZnO, BaO, GeO2, Ga2O3, and the like. Therefore, a total content percentage of Bi2O3, WO3, ZnO, BaO, GeO2, and Ga2O3 (Bi2O3+WO3+ZnO+BaO+GeO2+Ga2O3) is 15% to 50%. A lower limit of the total content percentage is preferably 25%, more preferably, 30%. An upper limit of the total content percentage is preferably 40%, more preferably, 35%.
A content percentage of a first oxide included in the main content components is 50% to 80%. A lower limit of the content percentage is preferably 55%, more preferably, 60%. An upper limit of the content percentage is preferably 75%, more preferably, 70%. It is preferred that oxides containing cations (Si4+, B3+, P5+, Li+, Na+, K+, Mg2+, Ca2+, Al3+, and/or Sr2+) that may be added as the additive target element, for example, oxides such as SiO2, B2O3, and P2O5 be not contained. The first oxide is more preferably TeO2.
A content percentage of a second oxide included in the main content components is 0% to 30%. A lower limit of the content percentage is preferably 5%, more preferably, 10%. An upper limit of the content percentage is preferably 25%, more preferably, 20%. Note that the second oxide is at least any one of Bi2O3, WO3, ZnO, BaO, GeO2, and Ga2O3. Note that, when the second oxide includes two or more kinds of oxides, similarly to a case in which the second oxide includes one kind of oxide, a content percentage of each oxide is also 0% to 30%.
When the second oxide is one or more kinds selected from Bi2O3, WO3, ZnO, BaO, GeO2, Ga2O3, the total content percentage of Bi2O3, WO3, ZnO, BaO, GeO2, and Ga2O3 (Bi2O3+WO3+ZnO+BaO+GeO2+Ga2O3) is preferably 15% to 50%.
A content percentage of a third oxide included in the main content components is 0% to 1%. An upper limit of the content percentage is preferably 0.5%. The third oxide is preferably at least any one of BeO, PbO, As2O3, Tl2O, CdO, UO2, and Th2O3. Note that, when the third oxide includes two or more kinds of oxides, similarly to a case in which the third oxide includes one kind of oxide, a content percentage of each oxide is also 0% to 1%.
When the third oxide is one or more kinds selected from BeO, PbO, As2O3, Tl2O, CdO, UO2, and Th2O3, the total content percentage of BeO, PbO, As2O3, Tl2O, CdO, UO2, and Th2O3 (BeO+PbO+As2O3+Tl2O+CdO+UO2+Th2O3) is further preferably 1% or less.
In accordance with a purpose of an element analysis or the like, in the glass composition according to the present embodiment, cations Si4+, B3+, P5+, Li+, Nat, K+, Mg2+, Ca2+, Al3+ and/or Sr2+ as the additive target element are each introduced by a mass of 1 mg/kg to 1,500 mg/kg (=mass ppm). As the cations that may be added as the additive target element, one to 10 kinds of additive elements may be selected for a piece of glass and added in a glass composition.
BeO, PbO, As2O3, Tl2O, CdO, UO2, and Th2O3 are components that disadvantageously affect a human body and the environment. Therefore, the concentration percentage of each of the components including BeO, PbO, As2O3, Tl2O, CdO, UO2, and Th2O3 is preferably 1% or less. Further, the total content percentage of BeO, PbO, As2O3, Tl2O, CdO, UO2, and Th2O3 (BeO+PbO+As2O3+Tl2O+CdO+UO2+Th2O3) is preferably 1% or less.
The components are not limited to those described above, and any other arbitrary components may be added within a range in which the glass composition being an object of the present embodiment can be achieved.
A method for producing a glass composition according to the present embodiment is described below.
The method for producing a glass composition according to the present embodiment includes:
Step i) to Step iii)
In order to prevent contamination with impurities, all the crucible and the tool for melting such as a lid and a stirring blade are immersed in advance in the acid solution, preferably for approximately 1 to 24 hours, more preferably, approximately 5 to 16 hours. The acid solution is preferably an acid solution including at least any one of a hydrofluoric acid, a hydrochloric acid, a nitric acid, and a sulfuric acid, more preferably, a hydrofluoric acid solution with a concentration of 30% to 50%. The crucible and the tool for melting such as a lid and a stirring blade that are immersed are cleansed, rinsed with purified water, and then dried.
The crucible and the tool for melting such as a lid and a stirring blade contain metal being at least any one of platinum, gold, and iridium because such metal has low reactivity with glass melt, which prevents erosion of the crucible with the melt, and has high acid resistance.
Step iv)
The main content components such as an oxide, a hydroxide, a carbonate, and a nitrate are weighed so as to obtain the above-mentioned component composition (mass %) of the glass composition according to the present embodiment.
The weighed main content components are mixed and fed into the crucible. Then, the additive target element is added by a certain amount, in accordance with a purpose. The additive target element is introduced by a method of directly feeding a raw material such as an oxide, a hydroxide, a carbonate, and a nitrate or a method of dripping a constant amount of a nitrate aqueous solution containing the additive target element. When the method of dripping a constant amount is adopted, the solution is not limited to the nitrate aqueous solution, and may be a solution in which the additive target element is stably dissolved.
The additive target elements are one or more kinds of cations selected from a group consisting of Si4+, B3+, P5+, Li+, Na+, K+, Mg2+, Ca2+, Al3+, and Sr2+, and are each added by a mass of 1 mg/kg to 1,500 mg/kg. As the cations that may be added as the additive target element, one to 10 kinds of additive elements may be selected for a piece of glass and added in a glass composition.
The crucible is covered with a lid, and melting and stirring are performed for homogenization at a temperature of 800 degrees Celsius to 900 degrees Celsius, preferably, a temperature of 800 degrees Celsius to 850 degrees Celsius, for 30 minutes to 8 hours, preferably, 1 hour to 5 hours.
Step v)
After the temperature is suitably reduced, casting in a mold or the like is performed, and then slow cooling is performed. With this, each glass sample is obtained. In order to determinate vitrification, no crystallization is visually confirmed.
Suitable characteristics of the glass composition according to the present are described below.
A melting temperature of the glass composition according to the present embodiment is 900 degrees Celsius or lower, in order to prevent volatilization of the additive target element during melting, which changes a concentration level of the additive target element. An upper limit of the melting temperature is preferably 850 degrees Celsius, more preferably, 800 degrees Celsius.
The glass composition according to the present embodiment has devitrification resistance stability, and further contains an intended element by a minute amount while reducing a content amount of an unintended element.
The glass composition according to the present embodiment having the above-mentioned characteristics may be used as, for example, a standard solid sample for an element analysis, and may be used suitably as a standard solid sample that enables an analysis of Si4+, B3+, P5+, Li+, Na+, K+, Mg2+, Ca2+, Al3, or Sr2+, in particular.
Next, examples of the present invention and comparative examples are described. The present invention is not limited to those examples.
The glass composition in each of the examples and each of the comparative examples was produced by the following procedures.
First, according to chemical compositions (mass %) described in Table 1 to Table 8, glass raw materials such as an oxide, a hydroxide, a carbonate, and a nitrate were weighed so that the total weight thereof was 100 g.
In a case of an addition at a high concentration (200 ppm or more), the additive target element was introduced by a method of directly feeding raw materials containing the additive target element. In a case of an addition at a low concentration (less than 200 ppm), the additive target element was introduced by a method of dripping a constant amount of a nitrate aqueous solution containing the additive target element.
Subsequently, the weighed glass raw materials were mixed and fed in a platinum crucible, and were melted and stirred for homogenization at a temperature of 800 degrees Celsius to 1100 degrees Celsius, for 1 hour to 2 hours. Then, casting in a mold or the like was performed after the temperature was suitably reduced, and slow cooling was performed. With this, each glass sample was obtained. In order to determinate vitrification, no crystallization was visually confirmed.
In order to prevent contamination with impurities, all of a platinum crucible, a platinum lid used during melting, a platinum stirring blade used during melting were immersed in advance in a hydrofluoric acid solution with a concentration of 30% to 50% for approximately 5 to 16 hours for cleansing, rinsed with purified water, and then dried before use.
First, after cleansing a glass sample surface with a dilute acid, each of the glass samples thus produced was pulverized. The pulverized glass sample was dissolved in the acid solution, and the volume thereof was determined by pure water. The solution thus obtained was used as a test solution.
The test solution described above was subjected to an additive element quantitative analysis by using an ICP emission spectrometric apparatus (ICPS-8100 produced by Shimadzu Corporation) or an ICP mass spectroscopy apparatus (Agilent 7700x produced by Agilent Technologies). In this state, a liquid standard sample containing the additive target element at a known concentration was used to create a calibration curve within an appropriate concentration range. Then, an amount of the additive target element in the glass being an analysis target was obtained.
Tables 1 to 8 show a component composition (on a mass basis), a melting temperature, and presence or absence of devitrification in each of the examples and each of the comparative examples.
As shown above, it was confirmed that the glass composition in each of the examples had a low melting temperature without devitrification. Meanwhile, in Comparative Examples 2, 3, and 6, the melting temperature was 900 degrees Celsius or higher, and devitrification was confirmed in all the comparative examples.
Based on the ICP quantitative value of the glass composition in each of the examples, it was confirmed that the intended additive target element was introduced by the intended amount in the glass composition.
| Number | Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/011319 | Mar 2021 | WO | international |
The present invention claims priority to International Patent Application No. PCT/JP2021/011319, filed on Mar. 19, 2021, the contents of which are incorporated by reference herein in its entirety in designated states where the incorporation of documents by reference is approved.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2021/042286 | Nov 2021 | US |
| Child | 18225481 | US |
