Glass, crystallized glass, method for producing crystallized glass, light-emitting material, and glass fiber

Abstract

The purpose of the present invention is to provide glass having improved strength. Glass according to the present invention comprises: 20-60 mol% of B2O3; 10-55 mol% in total of at least one selected from the group consisting of Y2O3 and Al2O3; 5-30 mol% in total of at least one transition metal oxide containing a transition element other than Y and having a melting point of 900°C or higher; and 3-15 mol% in total of at least one oxide selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO.

Description

Glass, crystallized glass, method for manufacturing crystallized glass, light-emitting material, and glass fiber

[0001] This invention relates to glass, crystallized glass, a method for manufacturing crystallized glass, and a light-emitting material. Furthermore, this invention relates to glass for fiber, crystallized glass for fiber, a method for manufacturing the same, and glass fibers.

[0002] Crystallized glass, obtained by heat-treating glass, possesses both the inherent properties of glass, such as high transparency, a wide transmission wavelength range, and ease of molding, and properties unique to the crystalline material, by selecting precipitated crystals. It is expected to be a new functional material with nonlinear optical properties and ionic conductivity.

[0003] For example, Patent Document 1 proposes a crystallized glass characterized by containing 5 to 25 mol% titanium oxide, 3 to 15 mol% bismuth oxide, 45 to 75 mol% boron oxide, 5 to 25 mol% aluminum oxide, and 2 to 15 mol% alkaline earth metal oxide, and having precipitated titanium oxide crystals. It is stated that this crystallized glass is transparent and exhibits high photocatalytic function.

[0004] Furthermore, Patent Document 2 proposes a crystallized glass characterized by containing 25-25 mol% TiO, 3-15 mol% Bi2O, 45-75 mol% B2O, 5-20 mol% Al2O, 2-15 mol% MgO + CaO + SrO + BaO, and 0.3-1.8 mol% SnO, and having titania crystals precipitated. It is stated that this crystallized glass has sufficient visible light transmittance while maintaining photocatalytic function.

[0005] However, conventional oxide glass has the problem of being brittle due to its low strength. To obtain high-strength glass, chemical or physical strengthening of the glass surface is generally employed, but this method requires the formation of a strengthening layer of a certain thickness from the glass surface, making it difficult to manufacture thin glass. On the other hand, high-melting-point glass tends to have high strength, but there are limitations to melting high-melting-point glass using ordinary electric furnaces, and when using concentrating furnaces or laser heating, it is difficult to manufacture large pieces of glass like ordinary plate glass.

[0006] Furthermore, glass has excellent formability and is widely used as a base material, taking advantage of its ease of molding and processing, for large sheet glass, craft products, and thin glass sheets for smartphones.

[0007] Glass fibers are used to improve the mechanical strength of concrete and plastics, and for example, patent documents 3 to 7 disclose glass fibers with a high Young's modulus.

[0008] Furthermore, Non-Patent Document 1 summarizes the distribution of glass composition and Young's modulus, stating that glass compositions with a Young's modulus exceeding 100 GPa are rare in general silicate glass or borosilicate glass.

[0009] On the other hand, in glass produced by laser irradiation, as described in Non-Patent Literature 2, there are oxide glass compositions that exhibit a high Young's modulus, and glass compositions with a Young's modulus exceeding 175 GPa have also been reported. However, glasses with such compositions are prone to crystallization and are difficult to produce by conventional melting methods. Furthermore, as described in Non-Patent Literature 3, thermal stability against crystallization is required for the production of glass fibers, but to date, no glass material possessing both a high Young's modulus and a suitable fiber shape has been reported.

[0010] Japanese Patent Publication No. 2008-120655, Japanese Patent Publication No. 2009-57266, Japanese Patent No. 7659709 Specification, Japanese Patent Publication No. 2023-177226, Japanese Patent Publication No. 2023-176525, Japanese Patent Publication No. 2006-527158, Japanese Patent Publication No. 2003-201144

[0011] T. Rouxel et al., Journal of the American Ceramics Society, 100, 4374 (2017) Y. Guo et al., iScience, 24, 102735 (2021) H. Masai et al., Journal of Materials Research, 24, 288 (2009)

[0012] Therefore, the present invention aims to provide glass with improved strength. The present invention also aims to provide crystallized glass obtained from said glass, a method for manufacturing the same, and a light-emitting material containing said glass or crystallized glass. The present invention also aims to provide glass for fiber with improved strength. The present invention also aims to provide crystallized glass for fiber obtained from said glass for fiber, a method for manufacturing the same, and glass fibers obtained from said glass for fiber or crystallized glass for fiber.

[0013] The inventors of the present invention conducted diligent research to solve the aforementioned problems and discovered that a glass having a specific oxide composition possesses high strength, and that it combines high strength with the thermal stability necessary for fiberization. The present invention was completed by further research based on these findings.

[0014] That is, the present invention provides the invention in the following embodiments: <1> A glass comprising 20 to 60 mol% of B2O3, 10 to 55 mol% in total of at least one selected from the group consisting of Y2O3 and Al2O3, 5 to 30 mol% in total of at least one transition metal oxide containing a transition element other than Y and having a melting point of 900°C or higher, and 3 to 15 mol% in total of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO. <2> The glass according to <1>, wherein the transition element is a group 3, group 4, group 5, or group 6 element other than Y. <3> The glass according to <1>, wherein the transition metal oxide is at least one selected from the group consisting of TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, WO3, and oxides of rare earth elements other than Y. <4> A glass according to any one of <1> to <3>, containing a total of 10 to 55 mol% of Y2O3 and Al2O3. <5> A glass according to any one of <1> to <4>, containing 5 mol% or more of Y2O3 and 5 mol% or more of Al2O3. <6> A glass according to any one of <1> to <5>, wherein the transition metal oxide contains a total of 10 mol% or more of TiO2 and ZrO2. <7> A glass according to any one of <1> to <6>, which does not contain SiO2 or has an SiO2 content of 15 mol% or less. <8> A glass according to any one of <1> to <7>, which has a Young's modulus of 119 GPa or higher. <9> A glass according to any one of <1> to <8>, which has a glass transition temperature of 650°C or higher. <10> A glass according to any one of <1> to <9>, which has a Poisson's ratio of 0.27 or higher. <11> Crystallized glass obtained from the glass described in any of <1> to <10>. <12> A method for producing crystallized glass, comprising the step of heat-treating the glass described in any of <1> to <10>. <13> A light-emitting material containing the glass described in any of <1> to <10>. <14> A light-emitting material containing the crystallized glass described in <11>.<15> A fiber glass comprising a total of 10 to 60 mol% of at least one selected from the group consisting of B2O3 and SiO2, a total of 2 to 60 mol% of at least one selected from the group consisting of Y2O3 and Al2O3, a total of 1 to 30 mol% of at least one transition metal oxide containing a transition element other than Y and having a melting point of 900°C or higher, and a total of 1 to 15 mol% of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO, wherein the temperature difference ΔT(Tx-Tg) between the crystallization onset temperature (Tx) and the glass transition temperature (Tg) is 100°C or higher. <16> The fiber glass according to <15>, wherein the transition element is a group 3 element, group 4 element, group 5 element, or group 6 element other than Y. <17> The fiber glass according to <15> or <16>, wherein the transition metal oxide is at least one selected from the group consisting of TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, WO3, and oxides of rare earth elements other than Y. <18> The fiber glass according to any one of <15> to <17>, wherein the transition metal oxide contains a total of 10 mol% or more of at least one selected from the group consisting of TiO2 and ZrO2. <19> The fiber glass according to any one of <15> to <18>, wherein the Young's modulus is 90 GPa or higher. <20> The fiber glass according to any one of <15> to <19>, wherein the glass transition temperature is 550°C or higher. <21> The fiber glass according to any one of <15> to <20>, wherein the Poisson's ratio is 0.27 or higher. <22> Crystallized fiber glass obtained from the fiber glass according to any one of <15> to <21>. <23> A method for producing crystallized glass for fiber, comprising the step of heat-treating the glass for fiber described in any of <15> to <21>. <24> Glass fiber obtained from the glass for fiber described in any of <15> to <21>. <25> Glass fiber obtained from the crystallized glass for fiber described in <22>.

[0015] Because the glass of the present invention possesses high strength, it can be suitably used in applications where strength is required. Furthermore, because the glass for fiber of the present invention combines high strength with the thermal stability necessary for fiberization, it is possible to easily manufacture high-quality glass fibers with improved strength.

[0016] This is a schematic diagram illustrating the measurement method using the ultrasonic pulse method. It also shows the schematic diagram of the crystallization onset temperature and glass transition temperature obtained from the differential thermal analysis curve of powdered glass. The differential thermal analysis curve for bulk glass samples is also shown.

[0017] 1. Glass The glass of the present invention contains 20 to 60 mol% of B2O3, 10 to 55 mol% in total of at least one selected from the group consisting of Y2O3 and Al2O3, 5 to 30 mol% in total of at least one transition metal oxide containing a transition element other than Y and having a melting point of 900°C or higher, and 3 to 15 mol% in total of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO. The glass of the present invention will be described in detail below.

[0018] The glass of the present invention contains 20 to 60 mol% of B2O3. B2O3 is a component that constitutes the framework of the glass network structure.

[0019] In the glass of the present invention, the B2O3 content is preferably 25 to 55 mol%, more preferably 30 to 50 mol%, and even more preferably 35 to 45 mol%, from the viewpoint of further improving the strength of the glass.

[0020] The glass of the present invention contains at least one selected from the group consisting of Y2O3 and Al2O3. Y2O3 and Al2O3 are components that increase the strength of the glass of the present invention. From the viewpoint of further improving the strength of the glass, it is preferable that the glass of the present invention contains both Y2O3 and Al2O3.

[0021] In the glass of the present invention, the total content of at least one selected from the group consisting of Y2O3 and Al2O3 is 10 to 55 mol%, preferably 15 to 50 mol%, more preferably 20 to 45 mol%, and even more preferably 25 to 45 mol%, from the viewpoint of further improving the strength of the glass. When both Y2O3 and Al2O3 are included, from the viewpoint of further improving the strength of the glass, it is preferable to include 5 mol% or more of Y2O3 and 5 mol% or more of Al2O3, and more preferably 10 mol% or more of Y2O3 and 10 mol% or more of Al2O3.

[0022] In the glass of the present invention, when both Y2O3 and Al2O3 are included, the content ratio of these is not particularly limited. However, from the viewpoint of further improving the strength of the glass, the Y2O3 / Al2O3 (molar ratio) is preferably 0.1 to 10, more preferably 0.15 to 8, even more preferably 0.2 to 6, even more preferably 0.25 to 4, and particularly preferably 0.25 to 3.

[0023] The glass of the present invention contains a transition element other than Y, and contains a total of 5 to 30 mol% of at least one transition metal oxide having a melting point of 900°C or higher. The transition metal oxide is a component that increases the strength of the glass of the present invention. The transition element other than Y is not particularly limited, but from the viewpoint of further improving the strength of the glass, it is preferably a group 3, group 4, group 5, or group 6 element other than Y. Among the group 3 elements other than Y, from the viewpoint of the above, it is preferably a rare earth element other than Y. Among the group 4 elements, from the viewpoint of the above, it is preferably Ti, Zr, and Hf. Among the group 5 elements, from the viewpoint of the above, it is preferably Nb and Ta. Among the group 6 elements, from the viewpoint of the above, it is preferably W.

[0024] The transition metal oxides are preferably TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, WO3, and oxides of rare earth elements other than Y (for example, La2O3 and Lu2O3). These may be included individually or in combination of two or more. From the viewpoint of further improving the strength of the glass, the transition metal oxides are preferably TiO2 and ZrO2.

[0025] When the glass of the present invention is used as a light-emitting material, it is preferable that the transition elements other than Y are light-emitting elements. Light-emitting elements are elements that, when added to the base material, become light-emitting centers and exhibit fluorescence in the ultraviolet, visible, and infrared regions. Examples of light-emitting elements include Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ti, Cr, Mn, Fe, Co, Ni, Cu, and Ag. These may be included individually or in groups of two or more.

[0026] In the glass of the present invention, the total content of the transition metal oxide is preferably 10 to 25 mol%, more preferably 10 to 20 mol%, from the viewpoint of further improving the strength of the glass. Furthermore, from the viewpoint of further improving the strength of the glass, the transition metal oxide preferably contains a total of 10 mol% or more of TiO2 and ZrO2, and more preferably contains a total of 15 mol% or more of TiO2 and ZrO2.

[0027] The glass of the present invention contains a total of 3 to 15 mol% of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO. Alkali metal oxides and alkaline earth metal oxides are components that enhance the meltability of the glass and also enhance the strength of the glass of the present invention. ZnO is a component with a relatively low melting point among divalent oxides and is not a coloring component, so it can be a component that constitutes the glass of the present invention in place of alkaline earth metals. The glass of the present invention is particularly preferably composed of alkaline earth metal oxides. The alkali metal oxide is not particularly limited, but from the viewpoint of further improving the strength of the glass, Li2O is preferred. The alkaline earth metal oxide is also not particularly limited, but from the above viewpoint, MgO, CaO, and BaO are preferred, and MgO and CaO are more preferred. One of these may be included, or two or more may be included.

[0028] In the glass of the present invention, the content of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO is preferably 4 to 12 mol%, more preferably 5 to 10 mol%, in total, from the viewpoint of further improving the strength of the glass.

[0029] Further, the glass of the present invention may contain other components in addition to the essential components. The other components are not particularly limited, and examples thereof include known components used in manufacturing glass. Examples of the other components include CdO, In₂O₃, SnO, PbO, Sb₂O₃, and Bi₂O₃. These may be contained singly or in combination of two or more.

[0030] Further, when the glass of the present invention is used as a luminescent material, the glass of the present invention may contain, as other components, at least one luminescent component selected from the group consisting of CdO, In₂O₃, SnO, PbO, and Bi₂O₃. Further, the glass of the present invention may contain one or more halides (e.g., fluorides and chlorides) of luminescent elements such as Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ti, Cr, Mn, Fe, Co, Ni, Cu, Ag, Cd, In, Sn, Pb, and Bi.

[0031] When the glass of the present invention contains other components, the content of the other components is usually 15 mol% or less, and from the viewpoint of further improving the strength of the glass, it is preferably 10 mol% or less, more preferably 5 mol% or less.

[0032] Further, from the viewpoint of enhancing the strength, the glass of the present invention preferably does not contain SiO₂ which is a main component of general glass, or the content of SiO₂ is 15 mol% or less. From the above viewpoint, the content of SiO₂ is more preferably 10 mol% or less, still more preferably 5 mol% or less, even more preferably 3 mol% or less, still more preferably 2 mol% or less, particularly preferably 1 mol% or less.

[0033] Further, from the viewpoint of enhancing the strength, the glass of the present invention preferably does not contain P₂O₅ which is a component for enhancing the melting property of the glass, or the content of P₂O₅ is 10 mol% or less. From the above viewpoint, the content of P₂O₅ is more preferably 5 mol% or less, still more preferably 3 mol% or less, even more preferably 2 mol% or less, particularly preferably 1 mol% or less.

[0034] From the perspective of further improving the strength of the glass, the Young's modulus of the glass of the present invention is preferably 119 GPa or more, more preferably 125 GPa or more, still more preferably 130 GPa or more, even more preferably 135 GPa or more, and particularly preferably 140 GPa or more. Also, the Young's modulus of the glass of the present invention is usually 200 GPa or less, and from the perspective of facilitating polishing, it is preferably 190 GPa or less, more preferably 180 GPa or less. In the present invention, the Young's modulus is a value measured by the ultrasonic pulse method.

[0035] From the perspective of further improving the strength of the glass, the larger the Poisson's ratio of the glass of the present invention, the closer it is to a metallic glass with densely packed atoms, and it is considered more desirable. The glass of the present invention preferably has a Poisson's ratio of 0.27 or more, more preferably 0.28 or more, still more preferably 0.29 or more, even more preferably 0.30 or more. In the present invention, the Poisson's ratio is a value measured by the ultrasonic pulse method.

[0036] From the perspective of further improving the strength of the glass, the glass transition temperature (Tg) of the glass of the present invention is preferably 650 °C or more, more preferably 660 °C or more, still more preferably 670 °C or more, even more preferably 680 °C or more, still more preferably 690 °C or more, even more preferably 700 °C or more, and particularly preferably 720 °C or more. The glass transition temperature of the glass of the present invention is usually 800 °C or less, and from the perspective of the melting property of the glass, it is preferably 780 °C or less, more preferably 760 °C or less. In the present invention, the glass transition temperature is a value measured by differential thermal analysis (DTA).

[0037] From the perspective of precise manufacturing, the linear thermal expansion coefficient of the glass of the present invention is preferably 100×10 -7 / °C or less, more preferably 80×10 -7 / °C or less, still more preferably 70×10 -7 / °C or less. In the present invention, the linear thermal expansion coefficient is a value measured in the atmosphere using a thermo - dilatometer under the condition of a heating rate of 10 °C / min. [[ID=十六]] [[ID=十七]]

[0038] The method for manufacturing the glass of the present invention is not particularly limited and may be manufactured by known methods. For example, a method for manufacturing the glass of the present invention involves mixing the essential components and other components used as needed in the aforementioned proportions, and then melting the resulting mixture. The melting method is not particularly limited and can be a known method. For example, a method may involve heating the mixture in a crucible at a temperature of about 1300 to 1650°C for about 0.25 to 12 hours to melt it.

[0039] Because the glass of the present invention has high strength, it is suitable for use as cover glass in mobile electronic devices such as mobile phones, smartphones, personal digital assistants (PDAs), and tablet devices; as cover glass for electronic devices such as televisions (TVs), personal computers (PCs), and touch panels; as building materials such as window glass; and for use in tabletops, automobiles, airplanes, and other interior applications.

[0040] Since the glass of the present invention can be drawn as glass fibers, it can also be used as glass fibers that can reinforce resins and the like. It is suitable for reinforcing various plastics, especially plastics used in harsh environments where durability is required.

[0041] 2. Crystallized Glass The crystallized glass of the present invention is obtained from the glass of the present invention as described above. The method for manufacturing the crystallized glass of the present invention is not particularly limited and may be manufactured by known methods. For example, a method for manufacturing the crystallized glass of the present invention may include a first step of mixing the essential components and other components used as needed in the above proportions to obtain a mixture, a second step of melting the mixture, and a third step of cooling the molten mixture.

[0042] In the second step, melting should be carried out in a temperature range where the components melt and become viscous enough to be poured out of the crucible. The melting temperature is usually around 1300 to 1650°C.

[0043] In the third step, the molten mixture may be cooled by allowing it to cool naturally, or by rapidly cooling the molten mixture. Generally, it is cooled by press quenching or by allowing the molten liquid to cool naturally, but any method may be used to cool the mixture. The cooling rate is 10 in the case of press quenching. 3 ~10 5 (K / min) is approximately, and in the case of air cooling it is 10 to 10 2 It is approximately (kJ / min).

[0044] Furthermore, if glass consisting solely of the glass phase is obtained through steps 1 to 3, crystallized glass may be produced after step 3 by heat-treating the glass within the range from the glass transition temperature (Tg) to the crystallization peak temperature (Tp). The glass transition temperature (Tg) and crystallization peak temperature (Tp) can be measured by differential thermal analysis (DTA). The heat treatment time required for crystallization varies depending on the composition of the glass and the heat treatment temperature, but is usually between 1 minute and 12 hours.

[0045] 3. Light-emitting material The light-emitting material of the present invention includes the glass, glass fiber, or crystallized glass of the present invention. The light-emitting material of the present invention is suitably used, for example, in light-emitting devices, vehicle windshields having light-emitting functions, indoor and outdoor sensors, and the like.

[0046] 4. Fiberglass The fiberglass of the present invention contains a total of 10 to 60 mol% of at least one selected from the group consisting of B2O3 and SiO2, a total of 2 to 60 mol% of at least one selected from the group consisting of Y2O3 and Al2O3, a total of 1 to 30 mol% of at least one transition metal oxide containing a transition element other than Y and having a melting point of 900°C or higher, and a total of 1 to 15 mol% of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO, and the temperature difference ΔT (Tx - Tg) between the crystallization onset temperature (Tx) and the glass transition temperature (Tg) is 100°C or higher. The fiberglass of the present invention (also simply referred to as "glass" in paragraphs 0047 to 0073) will be described in detail below.

[0047] The glass of the present invention contains a total of 10 to 60 mol% of at least one selected from the group consisting of B2O3 and SiO2. B2O3 and SiO2 are components that constitute the framework of the glass network structure.

[0048] In the glass of the present invention, the content of at least one substance selected from the group consisting of B2O3 and SiO2 is preferably 20 to 55 mol%, more preferably 24 to 50 mol%, in total, from the viewpoint of further improving strength and thermal stability (hereinafter also simply referred to as "thermal stability") necessary for fiber formation. From the viewpoint of further improving strength and thermal stability, the glass of the present invention preferably contains both B2O3 and SiO2.

[0049] In the glass of the present invention, when both B2O3 and SiO2 are present, the content ratio of these is not particularly limited. However, from the viewpoint of further improving strength and thermal stability, the B2O3 / SiO2 (molar ratio) is preferably 0.1 to 40, more preferably 1 to 30, even more preferably 2 to 20, and even more preferably 2 to 15.

[0050] The glass of the present invention contains a total of 2 to 60 mol% of at least one selected from the group consisting of Y2O3 and Al2O3. Y2O3 and Al2O3 are components that enhance the strength of the glass of the present invention.

[0051] In the glass of the present invention, the content of at least one selected from the group consisting of Y2O3 and Al2O3 is preferably 10 to 54.5 mol%, more preferably 15 to 50 mol%, and even more preferably 20 to 45 mol%, in total, from the viewpoint of further improving strength and thermal stability. From the viewpoint of further improving strength and thermal stability, the glass of the present invention preferably contains both Y2O3 and Al2O3.

[0052] In the glass of the present invention, when both Y2O3 and Al2O3 are included, the content ratio of these is not particularly limited. However, from the viewpoint of further improving strength and thermal stability, the Y2O3 / Al2O3 (molar ratio) is preferably 0.2 to 3.5, more preferably 0.3 to 2.5, even more preferably 0.4 to 2, and even more preferably 0.5 to 2.

[0053] The glass of the present invention contains a transition element other than Y, and contains a total of 1 to 30 mol% of at least one transition metal oxide having a melting point of 900°C or higher. The transition metal oxide is a component that increases the strength of the glass of the present invention. The transition element other than Y is not particularly limited, but from the viewpoint of further improving the strength of the glass, it is preferably a group 3, group 4, group 5, or group 6 element other than Y. Among the group 3 elements other than Y, from the viewpoint of the above, it is preferably a rare earth element other than Y. Among the group 4 elements, from the viewpoint of the above, it is preferably Ti, Zr, and Hf. Among the group 5 elements, from the viewpoint of the above, it is preferably Nb and Ta. Among the group 6 elements, from the viewpoint of the above, it is preferably W.

[0054] The transition metal oxides are preferably TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, WO3, and oxides of rare earth elements other than Y (for example, La2O3, Lu2O3, and CeO2). These may be included individually or in combination of two or more.

[0055] In the glass of the present invention, the total content of the transition metal oxide is preferably 5 to 30 mol%, more preferably 10 to 26 mol%, and even more preferably 10 to 20 mol%, from the viewpoint of further improving strength and thermal stability.

[0056] In the glass of the present invention, from the viewpoint of further improving strength and thermal stability, it is preferable that at least one selected from the group consisting of TiO2 and ZrO2 is included in a total of 10 mol% or more, more preferably 10 to 23 mol%, and even more preferably 10 to 20 mol%. In the glass of the present invention, from the viewpoint of further improving strength and thermal stability, it is preferable that both TiO2 and ZrO2 are included.

[0057] The glass of the present invention contains a total of 1 to 15 mol% of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO. Alkali metal oxides and alkaline earth metal oxides are components that enhance the meltability of the glass and also enhance the strength of the glass of the present invention. ZnO is a component with a relatively low melting point among divalent oxides and is not a coloring component, so it can be a component that constitutes the glass of the present invention in place of alkaline earth metals. The glass of the present invention is preferably particularly rich in alkaline earth metal oxides. The alkali metal oxide is not particularly limited, but from the viewpoint of further improving the strength of the glass, Li2O is preferred. The alkaline earth metal oxide is also not particularly limited, but from the above viewpoint, MgO, CaO, and BaO are preferred, and MgO and CaO are more preferred. One of these may be included, or two or more may be included.

[0058] In the glass of the present invention, the content of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO is preferably 3 to 14 mol%, more preferably 3 to 10 mol%, in total, from the viewpoint of further improving strength and thermal stability.

[0059] Furthermore, the glass of the present invention may contain other components in addition to the essential components mentioned above. The other components are not particularly limited and include known components used in the manufacture of glass. Examples of other components include oxides of CdO, In2O3, SnO, PbO, Sb2O3, P2O5, and Bi2O3. These may be present individually or in groups of two or more.

[0060] If the glass of the present invention contains other oxides, the content of other oxides is, for example, 15 mol% or less, preferably 10 mol% or less, more preferably 5 mol% or less, even more preferably 3 mol% or less, particularly preferably 1 mol% or less, and most preferably 0 mol%, that is, it is most preferable that it does not contain other oxides.

[0061] From the viewpoint of further improving the strength of the glass, the Young's modulus of the glass of the present invention is preferably 90 GPa or higher, more preferably 100 GPa or higher, even more preferably 110 GPa or higher, even more preferably 120 GPa or higher, and particularly preferably 130 GPa or higher. Furthermore, the Young's modulus of the glass of the present invention is usually 200 GPa or lower, and from the viewpoint of achieving a good balance between strength and thermal stability, it is preferably 190 GPa or lower, more preferably 180 GPa or lower, even more preferably 170 GPa or lower, and even more preferably 160 GPa or lower. In the present invention, the Young's modulus is a value measured by the ultrasonic pulse method.

[0062] From the viewpoint of further improving the strength of the glass, a larger Poisson's ratio is considered more desirable, as it brings the glass closer to a densely packed metallic glass. The glass of the present invention preferably has a Poisson's ratio of 0.27 or higher, more preferably 0.28 or higher, even more preferably 0.29 or higher, and even more preferably 0.30 or higher. In the present invention, the Poisson's ratio is a value measured by the ultrasonic pulse method.

[0063] From the viewpoint of further improving the strength of the glass, the higher the Vickers hardness of the glass in the present invention, the harder and more desirable the material is. The glass of the present invention preferably has a Vickers hardness of 700 HV 0.2 or higher, more preferably 750 HV 0.2 or higher, even more preferably 800 HV 0.2 or higher, even more preferably 850 HV 0.2 or higher, particularly preferably 900 HV 0.2 or higher, and most preferably 950 HV 0.2 or higher. In the present invention, Vickers hardness is a value determined by a Vickers hardness test.

[0064] From the viewpoint of further improving the strength of the glass, the glass transition temperature (Tg) of the present invention is preferably 550°C or higher, more preferably 550°C or higher, even more preferably 580°C or higher, even more preferably 600°C or higher, and particularly preferably 630°C or higher. The glass transition temperature of the glass of the present invention is usually 830°C or lower, and from the viewpoint of the meltability of the glass, it is preferably 800°C or lower, and more preferably 770°C or lower. In the present invention, the glass transition temperature (Tg) and the crystallization onset temperature (Tx), which will be described later, are values ​​measured by differential thermal analysis (DTA) using powdered glass.

[0065] The glass of the present invention has a temperature difference ΔT (Tx - Tg) between the crystallization start temperature (Tx) and the glass transition temperature (Tg) of 100°C or higher, preferably 105°C or higher, more preferably 110°C or higher, and even more preferably 120°C or higher, in order to improve the thermal stability necessary for fiberization. If ΔT is less than 100°C, when the molten glass is drawn out from the nozzle and fiberized, the glass is more likely to crystallize, causing strain at the interface between the crystalline and amorphous parts, which makes it easier for cracks to form in the glass fibers. If ΔT is 100°C or higher, the glass is less likely to crystallize when fiberized, so the occurrence of cracks in the glass fibers can be effectively suppressed.

[0066] In the glass of the present invention, as a method for making ΔT 100 °C or higher, for example, there is a method of adjusting the glass composition within the range of the content of each of the above glass components. Specifically, by adopting the following glass compositions alone or in combination, it becomes easier to adjust ΔT to 100 °C or higher. (1) Make the total content of Y2O3 and Al2O3 54.5 mol% or less. (2) Make the total content of TiO2 and ZrO2 5 mol% or more. (3) Make the total content of Y2O3 and Al2O3 42 mol% or less, or make the total content of Y2O3 and Al2O3 more than 42 mol% and 54.5 mol% or less, and make the total content of alkali metal oxides, alkaline earth metal oxides, and ZnO less than 10 mol%. (4) Make (total content of B2O3 and SiO2) - (total content of Y2O3, Al2O3, and transition metal oxides) -35 mol% or more, preferably -30 mol% or more. (5) Replace part of MgO with CaO or other alkaline earth metal element oxides. (6) As a preferable condition in the above (2), contain both TiO2 and ZrO2.

[0067] When using MgO as a raw material, a higher melting temperature is required compared to when using CaO. Due to melting at high temperatures, Ti 4+ is liable to be reduced to Ti 3+ . The reduced Ti 3+ promotes crystallization in the glass, so ΔT tends to decrease. Therefore, it is desirable to add CaO to lower the melting temperature or add an oxidizing agent (such as CeO2) to make Ti 4+ in order to inhibit the generation of Ti 3+ .

[0068] The manufacturing method of the glass of the present invention is not particularly limited, and it may be manufactured by a known method. As the manufacturing method of the glass of the present invention, for example, there is a method of mixing the above essential components and other components used as necessary so as to have the above content ratio, and melting the obtained mixture. The melting method is not particularly limited, and a known method can be adopted. For example, there is a method of melting the mixture by heating it at a temperature condition of about 1300 to 1650 °C for about 0.25 to 12 hours using a crucible.

[0069] 5. Crystallized Glass for Fibers The crystallized glass for fibers of the present invention (hereinafter also simply referred to as "crystallized glass") is obtained from the glass of the present invention as described above. The method for manufacturing the crystallized glass of the present invention is not particularly limited and can be manufactured by known methods. For example, a method for manufacturing the crystallized glass of the present invention includes a first step of mixing the essential components and other components used as needed in the above proportions to obtain a mixture, a second step of melting the mixture, and a third step of cooling the molten mixture.

[0070] In the second step, melting should be carried out in a temperature range where the components melt and become viscous enough to be poured out of the crucible. The melting temperature is usually around 1300 to 1650°C.

[0071] In the third step, the molten mixture may be cooled by allowing it to cool naturally, or by rapidly cooling the molten mixture. Generally, it is cooled by press quenching or by allowing the molten liquid to cool naturally, but any method may be used to cool the mixture. The cooling rate is 10 in the case of press quenching. 3 ~10 5 (K / min) is approximately, and in the case of air cooling it is 10 to 10 2 It is approximately (kJ / min).

[0072] Furthermore, if glass consisting solely of the glass phase is obtained through steps 1 to 3, crystallized glass may be produced after step 3 by heat-treating the glass within the range from the glass transition temperature (Tg) to the crystallization peak temperature (Tp). The glass transition temperature (Tg) and crystallization peak temperature (Tp) are measured by differential thermal analysis (DTA). The heat treatment time required for crystallization varies depending on the composition of the glass and the heat treatment temperature, but is usually between 1 minute and 12 hours.

[0073] 6. Glass Fibers The glass fibers of the present invention are obtained using the glass or crystallized glass of the present invention by known methods, for example, by drawing molten glass from a nozzle and forming it into fibers. The glass fibers of the present invention not only have high strength but are also of high quality, and are therefore suitable for reinforcing various plastics, especially plastics used in harsh environments where durability is required.

[0074] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0075] 1. Glass Example 1 5 mmol of calcium carbonate, 10 mmol of yttrium oxide, 45 mmol of boron oxide, 20 mmol of aluminum oxide, and 20 mmol of titanium oxide were weighed and mixed in a mortar. The resulting mixture was then added to a platinum crucible. The platinum crucible was placed in an electric furnace maintained at 1400°C, and after 30 minutes, the molten mixture was poured onto a stainless steel plate at 200°C and pressed from above with a stainless steel iron to obtain glass.

[0076] Glass having the composition of Example 1 was melted and rapidly cooled, then heat-treated at the glass transition temperature (Tg) for 1 hour to remove residual strain, thereby obtaining glass with the desired composition.

[0077] Examples 2-27 and 34-54, Comparative Examples 1-14: Glasses with the compositions shown in Tables 1-3 were obtained using the same method as in Example 1. In the examples and comparative examples, barium carbonate and lithium carbonate were used as raw materials for Ba and Li, respectively. For other elements, oxides were used as raw materials.

[0078] The glass transition temperature (Tg) was measured using each glass obtained in Examples 1-27 and 34-54, and Comparative Examples 1-14. The Tg of each glass is shown in Tables 1-3. <Glass Transition Temperature (Tg)> The glass transition temperature (Tg) was measured using differential thermal analysis (DTA) with a Rigaku Thermo plus EVO2 in air at a heating rate of 10°C / min, using 30 mg of each obtained glass. A platinum pan was used as the measurement pan, and Al2O3 was used as the reference sample.

[0079] Examples 28-33 The glass obtained in Example 19 (glass transition temperature (Tg): 748°C, crystallization peak temperature (Tp): 916°C) was heat-treated under the conditions listed in Table 4 to obtain each crystallized glass.

[0080] Examples 55-57 The glass obtained in Example 39 (glass transition temperature (Tg): 750°C, crystallization peak temperature (Tp): 885°C) was heat-treated under the conditions listed in Table 5 to obtain each crystallized glass.

[0081] Example 58 The glass obtained in Example 45 (glass transition temperature (Tg): 744°C, crystallization peak temperature (Tp): 887°C) was heat-treated under the conditions listed in Table 5 to obtain each crystallized glass.

[0082] Examples 59 and 60: The glass obtained in Example 46 (glass transition temperature (Tg): 741°C, crystallization peak temperature (Tp): 881°C) was heat-treated under the conditions listed in Table 5 to obtain each crystallized glass.

[0083] The Young's modulus, Poisson's ratio, light transmittance, and linear thermal expansion coefficient were measured for each glass obtained in Examples 1 to 60 and Comparative Examples 1 to 14. The results are shown in Tables 1 to 5.

[0084] <Young's Modulus and Poisson's Ratio> The Young's modulus E0 and Poisson's ratio ν0 of a cylindrical glass sample with a diameter of 9 mm and a height of 9 mm were measured at room temperature using the ultrasonic pulse method. Measurements were performed using an ultrasonic pulse generator (DRR-300, JSR), an oscilloscope (TBS1102, Tektronix), a 10 MHz longitudinal wave probe, and a 5 MHz transverse wave probe. As shown in Figure 1, ultrasonic pulses were propagated from the top surface of the glass sample, reflected from the bottom surface, and measured as pulses returning to the top surface. From the ultrasonic pulse echoes obtained from the measurement, the velocities of longitudinal and transverse waves propagating through the glass sample were determined by the following equation (1), and the Young's modulus E0 and Poisson's ratio ν0 of the glass sample at room temperature were determined by the following equations (2) and (3). Here, H is the height of the glass sample, n is the number of reflections, and Δt n ρ is the time of the nth reflection, ρ is the density, and V is the reflection time. L , V S These represent the propagation speed of longitudinal waves and transverse waves, respectively.

[0085] <Light Transmittance> The light transmittance of a flat glass sample, approximately 1 mm thick, that had been mirror-polished using an abrasive was measured at room temperature. A UV-Vis-Near-Infrared spectrophotometer (UH4150, Hitachi High-Tech Science) was used to measure the transmittance in the wavelength range of 850 nm to 200 nm. The wavelengths at which the transmittance was 5%, 50%, and 80% were identified as λ5, λ5, and λ5, respectively. 50 , λ 80 This is described in Tables 1 and 2. λ 50 ya λ 80 Glass samples that possess this feature can be said to have high transparency in the visible range.

[0086] <Linear Thermal Expansion Coefficient> The linear thermal expansion coefficient of the glass samples in the temperature range of 290°C to 490°C was measured using rectangular glass samples with a length of 30 to 50 mm that had been mirror-polished with an abrasive. The measurements were performed in air using a thermal expander (DIL 402PC / 1) at a heating rate of 10°C / min.

[0087]

[0088]

[0089]

[0090]

[0091]

[0092] As shown in Tables 1 and 2, the glasses of Examples 1-27 and 34-54 were found to be high-strength (Young's modulus of 119 GPa or higher). Furthermore, the glasses of Examples 1-25, 27 and 34-54 were found to be glass that achieved both high strength and high transparency. In addition, as shown in Tables 4 and 5, the crystallized glasses of Examples 28-33 and 55-60 had a Young's modulus of 140 GPa or higher, and were found to be extremely high-strength glass.

[0093] Comparing Examples 1-4, it was found that substituting TiO2 with ZrO2 increased the Young's modulus. Comparing Examples 1, 7, and 8, or Examples 9 and 15, it was found that substituting B2O3 with Al2O3 increased the Young's modulus. Comparing Examples 1, 9, and 10, it was found that substituting Al2O3 with Y2O3 increased the Young's modulus. Comparing Examples 1 and 11, it was found that substituting CaO with MgO increased the Young's modulus. Comparing Examples 1 and 18, it was found that substituting TiO2 with ZrO2, B2O3 with Al2O3, and CaO with MgO significantly increased the Young's modulus. Comparing Examples 18 and 22, it was found that substituting B2O3 with Li2O lowered the glass transition temperature, enabling melting and processing at lower temperatures.

[0094] 2. Fiberglass Example 61 5 mmol of calcium carbonate, 20 mmol of lanthanum oxide, 10 mmol of yttrium oxide, 20 mmol of aluminum oxide, and 45 mmol of boron oxide were weighed and mixed in a mortar. The resulting powder was placed in a 30 ml platinum crucible and placed in an electric furnace heated to 1400°C. After heating in the electric furnace for 30 minutes to form a glass molten state, it was poured onto a stainless steel plate that had been preheated to 200°C and pressed from above with a stainless steel iron to obtain fiberglass.

[0095] Examples 62-109, Comparative Examples 15-28: Fiber glass with compositions shown in Tables 6-8 was obtained using the same method as in Example 61. In the examples and comparative examples, barium carbonate, calcium carbonate, and lithium carbonate were used as raw materials for Ba, Ca, and Li, respectively. For other elements, oxides were used as raw materials. It is not necessary to use oxides as raw materials; other starting materials may be used as long as the desired composition is achieved.

[0096] The fiber glass obtained in Examples 61-109 and Comparative Examples 15-28 was pulverized, and the glass transition temperature (Tg) and crystallization onset temperature (Tx) were measured using the resulting glass powder. The Tg, Tx, and ΔT(Tx-Tg) for each powder glass sample are shown in Tables 6-8.

[0097] <Glass Transition Temperature (Tg) and Crystallization Initiation Temperature (Tx)> Using a portion (30 mg) of the glass obtained in Example 61, the glass transition temperature (Tg) of the bulk glass sample was measured in air under conditions of heating rate of 10°C / min by differential thermal analysis (DTA) using a Rigaku Thermo plus EVO2. Using the obtained bulk Tg value, the remaining glass was thermal annealed in air in a general electric furnace for 1 hour to remove any residual strain in the glass from the time of production. Subsequently, the thermal annealed glass was crushed using a mortar and pestle to obtain a powder glass sample. Using this powder glass sample, the glass transition temperature (Tg) and crystallization initiation temperature (Tx) of the powder were measured in air under conditions of heating rate of 10°C / min by differential thermal analysis (DTA) using a Rigaku Thermo plus EVO2. The glass transition temperature (Tg) was defined as the temperature at which endothermic (temperature difference) was observed in the DTA curve, as shown in Figure 2. The crystallization onset temperature (Tx) was defined as the temperature at which the exothermic peak indicating crystallization began to rise in the DTA curve, as shown in Figure 2. The glass transition temperature (Tg) and crystallization onset temperature (Tx) of the powdered glass obtained in Examples 62-109 and Comparative Examples 15-28 were measured using the same method as described above. All ΔT(Tx-Tg) values ​​listed in Tables 6-8 are values ​​obtained from measurements of these powdered glass samples. As shown in Figure 2, the ΔT obtained from the DTA curve of the powdered sample is smaller than the ΔT obtained from the DTA curve of the bulk sample, indicating that DTA measurement of the powdered sample is necessary to evaluate thermal stability. The error bar for calculating the glass transition temperature in a single measurement was ±3 degrees, and the temperature difference between the bulk Tg and the powdered sample Tg was always ±3 degrees or less. A platinum pan was used as the measurement pan, and Al2O3 was used as the reference sample.

[0098] Each of the powdered glass obtained in Examples 61-109 and Comparative Examples 15-28 was added to a platinum crucible, and the platinum crucible was placed in an electric furnace maintained at 1400°C. After 30 minutes, the molten material was poured onto a stainless steel plate at 200°C and pressed from above with a stainless steel iron to obtain each type of glass.

[0099] Each of the obtained glasses was melted and rapidly cooled, then heat-treated at the glass transition temperature (Tg) for 1 hour to remove any remaining strain, thereby obtaining glasses of the desired composition. Using each of the obtained glasses, the Young's modulus and Poisson's ratio were measured by the method described above, and the Vickers hardness was measured by the method described below. The results are shown in Tables 6 to 8.

[0100] Conventional laser-based high-elasticity glass is produced by rapidly cooling materials with a small ΔT (low thermal stability) that are prone to crystallization. This method is unsuitable for the production of glass fibers by melting. On the other hand, the fiber glass of the present invention has high thermal stability, which suppresses unintended crystallization during the glass fiber manufacturing process and the resulting deterioration of fiber quality, making it suitable for glass fiber production. The great value of this invention lies in the discovery of a group of glass compositions that possess both high strength and the thermal stability necessary for fiber formation.

[0101] <Vickers Hardness> Vickers hardness (HV) was measured in an atmospheric environment at room temperature using a micro-Vickers hardness tester (Mitutoyo, HM-220). Under conditions of a load of 0.2 N and a holding time of 15 seconds, 10 indentations were made on each sample, and the average value of the 10 indentations was calculated.

[0102]

[0103]

[0104]

[0105] The fiber-reinforced glass of Examples 61 to 109 had a Young's modulus of 90 GPa or higher and a ΔT(Tx-Tg) of 100°C or higher, thus possessing both high strength and the thermal stability necessary for fiber formation. On the other hand, the fiber-reinforced glass of Comparative Examples 15 to 28 had high strength due to their high Young's modulus, but lacked the thermal stability necessary for fiber formation because their ΔT(Tx-Tg) was less than 100°C.

[0106] Comparing Example 68 with Comparative Example 26, it was found that substituting MgO with CaO increased ΔT. When MgO is used as the raw material, a higher melting temperature is required compared to when CaO is used. Furthermore, due to melting at high temperatures, Ti 4+ Ti 3+ It becomes easier to reduce to Ti. 3+ Because it promotes crystallization in the glass, ΔT tends to decrease. Comparative Example 26 is reduced Ti 3+ The discoloration was significant, and ΔT did not meet the requirement of 100°C or higher. Therefore, CaO was added to lower the melting temperature, or Ti 4+ To produce Ti, an oxidizing agent (such as CeO2) is added to create the glass. 3+ It is desirable to inhibit the generation of [the substance].

[0107] Comparing Example 74 with Comparative Example 26, it was found that ΔT increases when TiO2 is replaced with SiO2. As described above, Ti 3+ Because it promotes crystallization in the glass, ΔT tends to be small. On the other hand, since SiO2 is not easily reduced, the ΔT in Example 74 was above 100°C.

[0108] La2O3, which belongs to the same Group 3, is an oxide that forms glass more easily than Y2O3, melts at a lower temperature, and contributes less to the increase in elastic modulus. Therefore, Example 106, which uses La2O3, has a larger ΔT, but a lower glass transition temperature and a smaller Young's modulus compared to Example 100, which does not use La2O3.

Claims

1. A glass comprising 20 to 60 mol% of B2O3, 10 to 55 mol% in total of at least one selected from the group consisting of Y2O3 and Al2O3, 5 to 30 mol% in total of at least one transition metal oxide containing a transition element other than Y and having a melting point of 900°C or higher, and 3 to 15 mol% in total of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO.

2. The glass according to claim 1, wherein the transition element is a group 3 element, group 4 element, group 5 element, or group 6 element other than Y.

3. The glass according to claim 1, wherein the transition metal oxide is at least one selected from the group consisting of TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, WO3, and oxides of rare earth elements other than Y.

4. The glass according to claim 1, comprising a total of 10 to 55 mol% of Y2O3 and Al2O3.

5. The glass according to claim 1, comprising 5 mol% or more of Y2O3 and 5 mol% or more of Al2O3.

6. The glass according to claim 1, wherein the transition metal oxide contains a total of 10 mol% or more of TiO2 and ZrO2.

7. The glass according to claim 1, which does not contain SiO2 or has an SiO2 content of 15 mol% or less.

8. The glass according to claim 1, wherein the Young's modulus is 119 GPa or higher.

9. The glass according to claim 1, wherein the glass transition temperature is 650°C or higher.

10. The glass according to claim 1, wherein the Poisson's ratio is 0.27 or higher.

11. Crystallized glass obtained from the glass according to any one of claims 1 to 10.

12. A method for producing crystallized glass, comprising the step of heat-treating the glass according to any one of claims 1 to 10.

13. A light-emitting material comprising the glass described in any one of claims 1 to 10.

14. A light-emitting material comprising the crystallized glass described in claim 11.

15. A fiberglass comprising a total of 10 to 60 mol% of at least one selected from the group consisting of B2O3 and SiO2, a total of 2 to 60 mol% of at least one selected from the group consisting of Y2O3 and Al2O3, a total of 1 to 30 mol% of at least one transition metal oxide containing a transition element other than Y and having a melting point of 900°C or higher, and a total of 1 to 15 mol% of at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, and ZnO, wherein the temperature difference ΔT(Tx-Tg) between the crystallization onset temperature (Tx) and the glass transition temperature (Tg) is 100°C or higher.

16. The glass for fiber according to claim 15, wherein the transition element is a group 3 element, group 4 element, group 5 element, or group 6 element other than Y.

17. The glass for fibers according to claim 15, wherein the transition metal oxide is at least one selected from the group consisting of TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, WO3, and oxides of rare earth elements other than Y.

18. The fiber glass according to claim 15, wherein the transition metal oxide comprises a total of 10 mol% or more of at least one selected from the group consisting of TiO2 and ZrO2.

19. The fiber glass according to claim 15, wherein the Young's modulus is 90 GPa or higher.

20. The glass for fibers according to claim 15, wherein the glass transition temperature is 550°C or higher.

21. The fiber glass according to claim 15, wherein the Poisson's ratio is 0.27 or higher.

22. Crystallized glass for fibers obtained from the glass for fibers according to any one of claims 15 to 21.

23. A method for producing crystallized glass for fiber, comprising the step of heat-treating the glass for fiber according to any one of claims 15 to 21.

24. A glass fiber obtained from the glass for fiber according to any one of claims 15 to 21.

25. A glass fiber obtained from the crystallized glass for fiber according to claim 22.

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