Glass product for resin composite materials

Abstract

The present disclosure provides a novel glass product which is suitable for use in a resin composite material and is also suitable for mass production. The glass product according to the present disclosure is a glass product for resin composite materials, the glass product comprising a glass composition containing the following components: 55 ≤ SiO2 ≤ 70, 0 ≤ B2O3 < 2, 5 ≤ Al2O3 ≤ 15, 47 ≤ (SiO2-Al2O3) ≤ 60, 0.1 ≤ MgO ≤ 10, 10 ≤ CaO ≤ 30, 0 ≤ ZnO ≤ 2 and 0 ≤ (Li2O+Na2O+K2O) ≤ 4 wherein each of the amounts is expressed in % by mass.

Description

Glass products for resin composites

[0001] FIELD OF THE INVENTION The present invention relates to glass articles suitable for use in resin composites, and more particularly to glass articles having glass fibers or other shapes suitable for use in resin composites.

[0002] Glass fiber reinforced plastics (GFRP) are resin composites in which lightweight plastics with poor mechanical properties, such as tensile strength and elastic modulus, are reinforced with glass fibers, which have excellent tensile strength and elastic modulus. They are used in a variety of applications, including automotive parts and electronic and electrical equipment. E-glass fiber is the most widely used glass fiber for resin composites. Patent Document 1 discloses a glass fiber for resin reinforcement that has better alkali resistance than E-glass. The glass composition constituting this glass fiber contains, by weight, 12% to 21% zirconium oxide (ZrO2), and sodium oxide (Na2O) and potassium oxide (KO) in a range of 13% to 18% in total (see page 3, lower right column).

[0003] Japanese Patent Application Publication No. 3-257039

[0004] As the applications of resin composite materials expand, there is a demand for glass fibers and other glass products for resin composite materials that are suitable for mass production. Therefore, an object of the present invention is to provide a new glass product that is suitable for use in resin composite materials and also suitable for mass production.

[0005] The present invention provides a glass product for a resin composite material, comprising a glass composition containing, expressed in mass%, the following components: 55≦SiO2≦70, 0≦B2O3<2, 5≦Al2O3≦15, 47≦(SiO2−Al2O3)≦60, 0.1≦MgO≦10, 10≦CaO≦30, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4.

[0006] The present invention provides a new glass product suitable for use in resin composites and suitable for mass production.

[0007] The following describes embodiments of the present invention, but the following description is not intended to limit the present invention to any particular embodiment. In this specification, "substantially free" and "substantially free" mean a content of less than 0.1 mass%, less than 0.05 mass%, less than 0.01 mass%, even less than 0.005 mass%, particularly less than 0.003 mass%, and in some cases less than 0.001 mass%. "Substantially" allows for the inclusion of trace amounts of impurities derived from glass raw materials, manufacturing equipment, molding equipment, etc. "Major component" refers to the component with the highest content by mass. "T-Fe2O3" refers to total iron oxide converted to diiron trioxide (Fe2O3). "Alkali metal oxide" refers to lithium oxide (Li2O), sodium oxide (Na2O), and potassium oxide (KO). The upper and lower limits of the content described below can be combined arbitrarily.

[0008] According to this embodiment, glass fibers and other glass products suitable for reinforcing resin composites can be obtained while limiting the contents of diboron trioxide (BO), zinc oxide (ZnO), and alkali metal oxides in the glass composition. BO tends to scatter during melting of glass raw materials and corrodes the furnace walls of melting furnaces and regenerative furnaces. Therefore, a high BO content can affect the life of manufacturing equipment. A high ZnO content increases raw material costs. Glass compositions with limited contents of these components can be suitable for mass production. Furthermore, a high alkali metal oxide content can reduce the Young's modulus and other properties of glass products. Glass compositions with limited alkali metal oxide contents can have properties suitable for reinforcing resin composites. Below, we first describe the glass compositions that make up glass products in detail.

[0009] <Components of Glass Composition> One example of the glass composition (hereinafter referred to as glass composition A) contains, expressed in mass%, the following components: 55≦SiO2≦70, 0≦B2O3<2, 5≦Al2O3≦15, 47≦(SiO2−Al2O3)≦60, 0.1≦MgO≦10, 10≦CaO≦30, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4.

[0010] Glass composition A may be a composition that is substantially free of BaO and F2. Glass composition A may contain, in mass%, components in the range of 55≦SiO2≦67. Glass composition A may contain, in mass%, components in the range of 55≦SiO2≦65. Glass composition A may contain, in mass%, components in the range of 8≦Al2O3≦15. Glass composition A may contain, in mass%, components in the range of 47≦(SiO2−Al2O3)≦57. Glass composition A may contain, in mass%, components in the range of 1≦MgO≦5. Glass composition A may contain, in mass%, components in the range of 15≦CaO≦30. Glass composition A may contain, in mass%, components in the range of 0≦(Li2O+Na2O+KO)<2. Glass composition A may contain, in mass%, a component that satisfies 0≦TiO2≦5. Glass composition A may contain, in mass%, a component that satisfies 0≦ZrO2<1. Glass composition A may contain, in mass%, a component that satisfies 0≦ZrO2≦0.5. Glass composition A may contain, in mass%, a component that satisfies 0≦T-Fe2O3≦5. Glass composition A may contain, in mass%, a component that satisfies 0≦T-Fe2O3≦0.5. Glass composition A may contain, in mass%, a component that satisfies 0≦T-Fe2O3<0.1. Glass composition A may be substantially free of ZnO. Glass composition A may be substantially free of TiO2. Glass composition A may be substantially free of B2O3. The glass composition A may be substantially free of SrO. The glass composition A may be substantially free of ZrO.

[0011] The silicon dioxide (SiO2) content in glass composition A may be 55% by mass or more and 69% by mass or less. The aluminum oxide (Al2O3) content may be 5% by mass or more and 14% by mass or less. (SiO2 - Al2O3) may be 47% by mass or more and 57% by mass or less. The magnesium oxide (MgO) content may be 0.1% by mass or more and 8% by mass or less. The calcium oxide (CaO) content may be 10% by mass or more and 28% by mass or less. The diboron trioxide (BO3) content may be 0.1% by mass or more and less than 2% by mass. However, glass composition A may be a composition that substantially does not contain BO3. The zinc oxide (ZnO) content may be 0% by mass or more and 1% by mass or less. The total content of alkali metal oxides (Li2O + Na2O + KO) may be 0.1% by mass or more and 4% by mass or less. However, glass composition A may be a composition that is substantially free of alkali metal oxides. Glass composition A may contain T-Fe2O3 in the range of 0% by mass to 5% by mass. Glass composition A may be substantially free of components other than the above-mentioned components.

[0012] (Specific Examples of Glass Composition A) As more specific examples of glass composition A, composition A-1 and composition A-2 are shown below.

[0013] (Composition A-1) Composition A-1 contains the following components in mass %: 55≦SiO2≦67, 0≦B2O3<2, 5≦Al2O3≦15, 47≦(SiO2-Al2O3)≦57, 0.1≦MgO≦10, 10≦CaO≦30, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4, 0≦T-Fe2O3≦5

[0014] The glass composition having the glass composition A-1 has excellent heat resistance, is suppressed from being deformed when heated to a high temperature, and has excellent chemical durability, particularly acid resistance.

[0015] Each component in glass composition A-1 is described below. (SiO2) SiO2 is a component that forms the glass skeleton and is the main component of composition A-1. SiO2 also adjusts the devitrification temperature and viscosity during glass formation and improves acid resistance. The SiO2 content is 55% by mass or more and 67% by mass or less, but the lower limit of the SiO2 content can be 56% by mass or more, 57% by mass or more, 58% by mass or more, 59% by mass or more, or even more than 60% by mass. The upper limit of the SiO2 content can be 65% by mass or less, 64% by mass or less, or even 63% by mass or less.

[0016] (B2O3) B2O3 is a component that forms the skeleton of glass. B2O3 is also a component that adjusts the devitrification temperature and viscosity during glass formation. The lower limit of the B2O3 content may be 0.1 mass% or more. The upper limit of the B2O3 content may be less than 2 mass%, or may be 1.5 mass% or less, 1 mass% or less, or 0.5 mass% or less. The upper limit of the B2O3 content may be 0.1 mass% or less. Composition A-1 may be substantially free of B2O3.

[0017] (Al2O3) Al2O3 is a component that forms the glass skeleton. It also adjusts the devitrification temperature and viscosity during glass formation and improves the water resistance of the glass. On the other hand, excessive Al2O3 content reduces the acid resistance of the glass. An Al2O3 content of 5% by mass or more and 15% by mass or less suppresses the increase in the devitrification temperature of the glass that would make glass production difficult, and enhances the acid resistance of the glass. Furthermore, the melting point of the glass does not become excessively high, improving uniformity during melting of raw materials. The lower limit of the Al2O3 content can be 6% by mass or more, 7% by mass or more, 8% by mass or more, 8.5% by mass or more, 9% by mass or more, 9.5% by mass or more, 10% by mass or more, 10.5% by mass or more, 11% by mass or more, or even 11.1% by mass or more. The upper limit of the Al2O3 content may be 14 mass% or less, 13 mass% or less, 12.5 mass% or less, less than 12 mass%, or even 11.9 mass% or less.

[0018] (SiO2-Al2O3) From the viewpoint of improving the acid resistance of glass, the lower limit of the value obtained by subtracting the Al2O3 content from the SiO2 content (SiO2-Al2O3) may be 47 mass% or more, more than 48 mass%, 48.5 mass% or more, more than 49 mass%, or even 49.5 mass% or more. Furthermore, the upper limit of (SiO2-Al2O3) may be 57 mass% or less, 56 mass% or less, 55 mass% or less, 54 mass% or less, 53 mass% or less, or even 52 mass% or less.

[0019] (SiO2-B2O3-Al2O3) From the viewpoint of improving the acid resistance of glass, the lower limit of the value obtained by subtracting the B2O3 content from the SiO2 content and then further subtracting the Al2O3 content (SiO2-B2O3-Al2O3) may be 45 mass% or more, 46 mass% or more, 47 mass% or more, more than 48 mass%, 48.5 mass% or more, more than 49 mass%, or even 49.5 mass% or more. Furthermore, the upper limit of (SiO2-B2O3-Al2O3) may be 56 mass% or less, 55.5 mass% or less, 55 mass% or less, 54.5 mass% or less, 54 mass% or less, 53.5 mass% or less, 53 mass% or less, 52 mass% or less, or even 51 mass% or less.

[0020] (MgO, CaO) MgO and CaO are components that adjust the devitrification temperature and viscosity during glass formation. Furthermore, MgO and CaO are also components that improve Young's modulus. The MgO content is 0.1% by mass or more and 10% by mass or less, but the lower limit can be 0.5% by mass or more, 1% by mass or more, 1.5% by mass or more, or even 2% by mass or more. The upper limit of the MgO content can be 8% by mass or less, 6% by mass or less, 5% by mass or less, 4.5% by mass or less, or even 4% by mass or less.

[0021] The CaO content is 10% by mass or more and 30% by mass or less, but the lower limit can be 12% by mass or more, 13% by mass or more, 14% by mass or more, 15% by mass or more, 16% by mass or more, 17% by mass or more, or even 18% by mass or more. The upper limit of the CaO content can be 28% by mass or less, 27% by mass or less, 26% by mass or less, 25% by mass or less, 24.5% by mass or less, 24% by mass or less, or even 23% by mass or less.

[0022] (MgO + CaO) The sum of the contents of MgO and CaO (MgO + CaO) can affect the meltability and formability of glass. From the viewpoint of obtaining meltability and formability suitable for glass production, the lower limit of (MgO + CaO) is preferably 15 mass% or more, and can be 16 mass% or more, 17 mass% or more, 18 mass% or more, 19 mass% or more, 20 mass% or more, 21 mass% or more, or 22 mass% or more. Furthermore, the upper limit of (MgO + CaO) is preferably 40 mass% or less, and can be 35 mass% or less, 32 mass% or less, 30 mass% or less, 29 mass% or less, 28 mass% or less, 27 mass% or less, or 26 mass% or less.

[0023] (SrO) Composition A-1 may further contain strontium oxide (SrO). SrO is a component that adjusts the devitrification temperature and viscosity during glass formation. On the other hand, excessive SrO content reduces the acid resistance of the glass. The lower limit of the SrO content may be 0.1 mass% or more, 0.5 mass% or more, 1 mass% or more, 2 mass% or more, 3 mass% or more, 4 mass% or more, 5 mass% or more, 6 mass% or more, 7 mass% or more, or even 8 mass% or more. The upper limit of the SrO content may be 15 mass% or less, 12 mass% or less, 10 mass% or less, 8 mass% or less, 6 mass% or less, 5 mass% or less, 4 mass% or less, 3 mass% or less, 2 mass% or less, 1.5 mass% or less, 1 mass% or less, or 0.5 mass% or less. The upper limit of the SrO content may be 0.1 mass% or less. Composition A-1 may be substantially free of SrO.

[0024] (MgO + CaO + SrO) The total content of MgO, CaO, and SrO (MgO + CaO + SrO) can affect the meltability and formability of glass. From the viewpoint of obtaining meltability and formability suitable for glass production, the lower limit of (MgO + CaO + SrO) is preferably 15 mass% or more, and can be 18 mass% or more, 20 mass% or more, 21 mass% or more, 22 mass% or more, 23 mass% or more, 24 mass% or more, 25 mass% or more, 26 mass% or more, 27 mass% or more, or 28 mass% or more. Furthermore, the upper limit of (MgO + CaO + SrO) is preferably 40 mass% or less, and can be 38 mass% or less, 36 mass% or less, 35 mass% or less, or 34 mass% or less.

[0025] (BaO) Composition A-1 may further contain barium oxide (BaO). BaO is a component that adjusts the devitrification temperature and viscosity during glass formation. On the other hand, excessive BaO content reduces the acid resistance of the glass. The upper limit of the BaO content may be 10% by mass or less, or may be 5% by mass or less, 2% by mass or less, 1.5% by mass or less, 1% by mass or less, 0.5% by mass or less, or even 0.1% by mass or less. Composition A-1 may be substantially free of BaO.

[0026] (MgO + CaO + SrO + BaO) The total content of MgO, CaO, SrO, and BaO (MgO + CaO + SrO + BaO) can affect the meltability and formability of glass. From the viewpoint of obtaining meltability and formability suitable for glass production, the lower limit of (MgO + CaO + SrO + BaO) is preferably 15 mass% or more, and can be 18 mass% or more, 20 mass% or more, 21 mass% or more, 22 mass% or more, 23 mass% or more, 24 mass% or more, 25 mass% or more, 26 mass% or more, 27 mass% or more, or 28 mass% or more. Furthermore, the upper limit of (MgO + CaO + SrO + BaO) is preferably 40 mass% or less, and can be 38 mass% or less, 36 mass% or less, 35 mass% or less, or 34 mass% or less.

[0027] (ZnO) ZnO is a component that adjusts the devitrification temperature and viscosity during glass formation. However, since the raw material for ZnO is relatively expensive, its content should be low. The upper limit of the ZnO content can be 2 mass% or less, 1.5 mass% or less, 1 mass% or less, 0.5 mass% or less, or even 0.1 mass% or less. Composition A-1 may be substantially free of ZnO.

[0028] (Li2O, Na2O, K2O) Alkali metal oxides (Li2O, Na2O, K2O) are components that adjust the devitrification temperature and viscosity during glass formation. When the total content of alkali metal oxides (Li2O + Na2O + K2O) is 0% by mass or more and 4% by mass or less, the devitrification temperature and viscosity of the glass melt can be kept within ranges suitable for glass production while suppressing an excessive increase in the devitrification temperature. Furthermore, while suppressing an increase in the melting point of the glass and enabling more uniform melting of the glass raw materials, the glass transition temperature does not decrease excessively, ensuring high heat resistance of the glass. Furthermore, the acid resistance of the glass is improved. The lower limit of (Li2O + Na2O + K2O) may be greater than 0% by mass or may be 0.1% by mass or more. The upper limit of (Li2O + Na2O + K2O) may be 3% by mass or less, or 2% by mass or less, or less than 2% by mass. The value of (LiO + NaO + KO) may be 0.1 mass% or less. Composition A-1 may be substantially free of alkali metal oxides. LiO, NaO, and KO are each optional components. In other words, the lower limit of the content of each of these components may be 0.

[0029] The lower limit of the lithium oxide (LiO) content may be 0.1% by mass or more, 0.2% by mass or more, 0.3% by mass or more, or even 0.4% by mass or more. The upper limit of the LiO content may be 4% by mass or less, 3% by mass or less, 2% by mass or less, 1.5% by mass or less, or even 1% by mass or less.

[0030] The lower limit of the sodium oxide (NaO) content may be 0.1% by mass or more, or 0.2% by mass or more, and the upper limit of the NaO content may be 4% by mass or less, or 3% by mass or less, 2% by mass or less, 1.5% by mass or less, or even 1% by mass or less.

[0031] The lower limit of the potassium oxide (K2O) content may be 0.1 mass% or more, or 0.2 mass% or more, and the upper limit of the K2O content may be 4 mass% or less, or 3 mass% or less, 2 mass% or less, 1.5 mass% or less, or even 1 mass% or less.

[0032] (TiO2) Composition A-1 may further contain titanium dioxide (TiO2). TiO2 is a component that improves the meltability and chemical durability of glass and improves its UV absorption characteristics. TiO2 is also a component that improves the acid resistance and water resistance of glass. However, since the raw material for TiO2 is relatively expensive, a low TiO2 content is preferable. The lower limit of the TiO2 content may be 0.1% by mass or more. The upper limit of the TiO2 content may be 10% by mass or less, or may be 5% by mass or less, 4% by mass or less, 3% by mass or less, 2% by mass or less, 1% by mass or less, 0.5% by mass or less, 0.3% by mass or less, or even 0.2% by mass or less. Composition A-1 may be substantially free of TiO2.

[0033] (ZrO2) Composition A-1 may further contain zirconium oxide (ZrO2). ZrO2 is a component that adjusts the devitrification temperature and viscosity during glass formation. ZrO2 is also a component that improves the acid resistance and alkali resistance of the glass. However, since the raw material for ZrO2 is relatively expensive, its content is preferably low. The upper limit of the ZrO2 content may be 7% by mass or less, or may be 6% by mass or less, 5% by mass or less, 4% by mass or less, 3% by mass or less, 2% by mass or less, 1% by mass or less, less than 1% by mass, 0.5% by mass or less, or even 0.1% by mass or less. Composition A-1 may be substantially free of ZrO2.

[0034] (Fe) Composition A-1 may further contain iron oxide. Iron (Fe) is usually Fe 2+ or Fe 3+ It exists in the state of Fe 3+ is a component that enhances the ultraviolet absorption properties of glass, and Fe 2+is a component that enhances the heat absorption properties of glass. Even if not intentionally included, Fe can be unavoidably mixed in as an industrial raw material. A low Fe content can prevent coloration of the glass. The upper limit of the Fe content, expressed in T-Fe2O3, can be 5% by mass or less, or can be 2% by mass or less, 1% by mass or less, 0.5% by mass or less, 0.4% by mass or less, 0.3% by mass or less, 0.2% by mass or less, 0.1% by mass or less, less than 0.1% by mass, 0.08% by mass or less, 0.05% by mass or less, 0.04% by mass or less, or 0.03% by mass or less. The lower limit of the Fe content, expressed in T-Fe2O3, can be 0.01% by mass or more, 0.05% by mass or more, 0.1% by mass or more, or even 0.2% by mass or more. Particularly in glass compositions with low alkali metal oxide contents, trace amounts of iron oxide can contribute to promoting fining of the glass.

[0035] (F2, Cl2) Composition A-1 may further contain fluorine (F2) and chlorine (Cl2). F2 is easily volatile, which may cause scattering during melting, and also makes it difficult to control its content in the glass. The upper limit of the F2 content may be 5% by mass or less, or may be 2% by mass or less, 1% by mass or less, 0.5% by mass or less, 0.2% by mass or less, or even 0.1% by mass or less. Composition A-1 may be substantially free of F2.

[0036] Cl2 is easily volatile, which may cause scattering during melting, and also makes it difficult to control its content in the glass. The upper limit of the Cl2 content may be 5% by mass or less, or may be 2% by mass or less, 1% by mass or less, 0.5% by mass or less, 0.2% by mass or less, or even 0.1% by mass or less. Composition A-1 may be substantially free of Cl2.

[0037] Composition A-1 may have the preferred composition described in mass % in the following paragraphs.

[0038] A composition containing the components 55≦SiO2≦65, 0≦B2O3<2, 8≦Al2O3≦15, 47≦(SiO2-Al2O3)≦57, 1≦MgO≦5, 20≦CaO≦30, 0≦ZnO≦2, 0≦T-Fe2O3≦5, and substantially containing no alkali metal oxides.

[0039] A composition containing the following components: 60<SiO2≦67, 0≦B2O3<2, 8≦Al2O3<12, 48<(SiO2-Al2O3)≦57, 1≦MgO≦5, 20≦CaO≦30, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4, 0≦T-Fe2O3≦5.

[0040] A composition containing the following components: 57≦SiO2≦65, 0≦B2O3<2, 8≦Al2O3≦15, 47≦(SiO2−Al2O3)≦57, 1≦MgO≦5, 18≦CaO≦30, 0≦ZnO≦2, 0.1≦Li2O≦4, 0.1≦(Li2O+Na2O+K2O)≦4, 0≦T-Fe2O3≦5.

[0041] A composition containing the following components: 57≦SiO2≦65, 0≦B2O3<2, 8≦Al2O3<12, 47≦(SiO2−Al2O3)≦57, 1≦MgO≦5, 18≦CaO≦30, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4, 0≦T-Fe2O3≦5, and substantially not containing ZrO2.

[0042] A composition containing the following components: 57≦SiO2≦65, 0.1≦B2O3<2, 8≦Al2O3≦15, 45≦(SiO2-B2O3-Al2O3)≦56, 1≦MgO≦5, 15≦CaO≦30, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4, 0≦T-Fe2O3≦5.

[0043] A composition containing the following components: 55≦SiO2≦65, 0≦B2O3<2, 5≦Al2O3≦15, 47≦(SiO2−Al2O3)≦57, 0.1≦MgO≦5, 10≦CaO≦30, 0.1≦SrO≦15, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4, 0≦T-Fe2O3≦5.

[0044] In each of the above compositions, B2O3 is not substantially contained (except for compositions in which 0.1≦B2O3<2 is satisfied).

[0045] In each of the above compositions, the relationship 0≦TiO2≦2, particularly 0.1≦TiO2≦2, is further satisfied.

[0046] In each of the above compositions, ZnO is not substantially contained.

[0047] In each of the above compositions, TiO2 is not substantially contained.

[0048] In each of the above compositions (excluding compositions that do not substantially contain ZrO2), the following relationship further holds: 0≦ZrO2≦7.

[0049] In the above compositions, 0≦T-Fe2O3≦5 can be replaced with 0.1≦T-Fe2O3≦5.

[0050] (Composition A-2) Composition A-2 contains the following components expressed in mass %: 65<SiO2≦75, 0≦B2O3<2, 5≦Al2O3≦15, 50<(SiO2-Al2O3)≦60, 1≦MgO≦10, 10≦CaO≦25, 0≦ZnO≦2, 0≦(Li2O+Na2O+K2O)≦4, 0≦T-Fe2O3≦5,

[0051] Glass composition A-2 has excellent heat resistance, is suppressed from deformation when heated to high temperatures, and has excellent chemical durability, particularly acid resistance.

[0052] Each component in glass composition A-2 is described below. However, descriptions of the role of each component that overlap with those in glass compositions A-1 or A-2 will be omitted. (SiO2) SiO2 is also the main component in composition A-2. The SiO2 content is greater than 65 mass% and not more than 75 mass%, with the lower limit being 66 mass% or more. The upper limit of the SiO2 content can be 72 mass% or less, 70 mass% or less, 69 mass% or less, 68 mass% or less, or even 67 mass% or less.

[0053] (B2O3)(Al2O3) In composition A-2, the contents of B2O3 and Al2O3 may have the same upper and lower limits as in composition A-1.

[0054] (SiO2-Al2O3) In composition A-2, from the viewpoint of improving the acid resistance of the glass, the lower limit of the value obtained by subtracting the Al2O3 content from the SiO2 content (SiO2-Al2O3) can be more than 50 mass%, or 51 mass% or more, 52 mass% or more, or even more than 53 mass%. Furthermore, the upper limit of (SiO2-Al2O3) can be 60 mass% or less, or 59 mass% or less, 58 mass% or less, or even 57 mass% or less.

[0055] (MgO, CaO) In composition A-2, the MgO content is 1% by mass or more and 10% by mass or less. The lower limit of the MgO content can be 1.5% by mass or more, or even 2% by mass or more. The upper limit of the MgO content can be 8% by mass or less, or 6% by mass or less, 5% by mass or less, 4.5% by mass or less, or even 4% by mass or less.

[0056] In composition A-2, the CaO content is 10% by mass or more and 25% by mass or less. The lower limit of the CaO content can be 12% by mass or more, 13% by mass or more, 14% by mass or more, or even more than 15% by mass. The upper limit of the CaO content can be 23% by mass or less, 22% by mass or less, 21% by mass or less, or even 20% by mass or less.

[0057] (SrO) Composition A-2 may further contain SrO. In composition A-2, the upper limit of the SrO content may be 10% by mass or less, 5% by mass or less, 2% by mass or less, 1.5% by mass or less, 1% by mass or less, 0.5% by mass or less, or even less than 0.1% by mass. Composition A-2 may be substantially free of SrO.

[0058] (BaO) Composition A-2 may further contain BaO. The BaO content in composition A-2 may have the same upper and lower limits as in composition A-1. Composition A-2 may be substantially free of BaO.

[0059] (ZnO) In composition A-2, the content of ZnO may have the same upper and lower limits as in composition A-1. Composition A-2 may be substantially free of ZnO.

[0060] (Li2O, Na2O, KO) In composition A-2, the total content of alkali metal oxides (Li2O + Na2O + KO) is 0% by mass or more and 4% by mass or less. The lower limit of (Li2O + Na2O + KO) can be 0.1% by mass or more, 1% by mass or more, 1.5% by mass or more, or even 2% by mass or more. The upper limit of (Li2O + Na2O + KO) can be 3.5% by mass or less, or 3% by mass or less. Composition A-2 may be substantially free of alkali metal oxides. Li2O, Na2O, and KO are each optional components. In other words, the lower limit of the content of each of these components may be 0.

[0061] In composition A-2, LiO makes a particularly large contribution to the effects based on the alkali metal oxide described above. From this perspective, the lower limit of the LiO content in composition A-2 can be 0.1% by mass or more, 0.5% by mass or more, or even 1% by mass or more. The upper limit of the LiO content can be 4% by mass or less, 3% by mass or less, 2.5% by mass or less, or 2% by mass or less.

[0062] In composition A-2, the contents of Na2O and K2O may have the same upper and lower limits as those in composition A-1.

[0063] (TiO2) Composition A-2 may further contain TiO2. The content of TiO2 in composition A-2 may have the same upper and lower limits as composition A-1. Composition A-2 may be substantially free of TiO2.

[0064] (ZrO2) Composition A-2 may further contain ZrO2. The ZrO2 content in composition A-2 may have the same upper and lower limits as composition A-1. Composition A-2 may be substantially free of ZrO2. Composition A-2 may also further satisfy the condition 0≦ZrO2≦7.

[0065] (Fe) (F, Cl) Composition A-2 may contain Fe. Composition A-2 may further contain F and Cl. The preferred contents of these components and other details are the same as those for composition A-1, and therefore will not be described here.

[0066] (Other Components) Glass composition A may contain at least one other component selected from P2O5, Sc2O3, Y2O3, La2O3, CeO2, Pr2O3, Nd2O3, Pm2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, Lu2O3, WO3, Nb2O5, Y2O3, MoO3, Ta2O5, MnO2, and Cr2O3 in a content of 0% to 5% by mass. The allowable content of each of these components may be less than 2% by mass, less than 1% by mass, less than 0.5% by mass, or even less than 0.1% by mass. The total allowable content of these components may be 5% by mass or less, or may be less than 2%, less than 1%, less than 0.5%, or even less than 0.1% by mass. However, the above other components may not be substantially contained. Furthermore, oxides of light-bearing elements (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) may not be substantially contained.

[0067] Glass composition A may also contain at least one additive selected from SO3, Br2, I2, SnO2, As2O3, and Sb2O3, each in a content of 0% by mass or more and 1% by mass or less. The allowable content of each of these components may be less than 0.5% by mass, less than 0.2% by mass, or even less than 0.1% by mass. The allowable total content of these components may be 1% by mass or less, less than 0.5%, less than 0.2%, or even less than 0.1% by mass. However, the other components may not be substantially present.

[0068] Glass composition A may contain HO, OH, H, CO, CO, He, Ne, Ar, and N, each at a content of 0% by mass or more and 0.1% by mass or less. The allowable content of each of these components may be less than 0.05% by mass, less than 0.03% by mass, or even less than 0.01% by mass. The allowable total content of these components may be 0.1% by mass or less, less than 0.05% by mass, less than 0.03% by mass, or even less than 0.01% by mass. However, the above other components may not be substantially present.

[0069] Glass composition A may contain trace amounts of precious metal elements. For example, precious metal elements such as Pt, Rh, Au, and Os may be contained in a content of 0% by mass or more and 0.1% by mass or less, respectively. The allowable content of each of these components may be less than 0.1% by mass, less than 0.05% by mass, less than 0.03% by mass, or even less than 0.01% by mass. The allowable total content of these components may be 0.1% by mass or less, less than 0.05% by mass, less than 0.03% by mass, or even less than 0.01% by mass. However, the above other components may not be substantially present.

[0070] Glass composition A may be a composition that is substantially free of CuO. Also, glass composition A may be a composition that is substantially free of CoO. Furthermore, glass composition A may be a composition that is substantially free of PbO. Also, glass composition A may be a composition that is substantially free of NiO.

[0071] <Characteristics> The characteristics that the glass composition of this embodiment can have are described below. (Melting Characteristics) The temperature at which the viscosity of molten glass reaches 1000 dPa·sec (1000 poise) is called the working temperature of the glass, and is the temperature most suitable for forming the glass. When producing glass products such as glass fibers, if the working temperature of the glass is 1100°C or higher, variation in the shape of the glass product, such as the diameter of the glass fiber, can be reduced. If the working temperature is 1300°C or lower, fuel costs for melting the glass can be reduced, glass manufacturing equipment is less susceptible to thermal corrosion, and the life of the equipment can be extended. The lower limit of the working temperature can be 1100°C or higher, and can also be 1120°C or higher, 1140°C or higher, 1150°C or higher, 1160°C or higher, 1170°C or higher, 1180°C or higher, or even 1200°C or higher. The upper limit of the working temperature may be 1300°C or less, 1280°C or less, 1270°C or less, 1260°C or less, or even 1250°C or less.

[0072] The larger the temperature difference ΔT obtained by subtracting the devitrification temperature from the working temperature, the less likely devitrification occurs during glass molding, and homogeneous glass can be produced with a high yield. ΔT can be 0°C or higher, or 10°C or higher, 20°C or higher, 30°C or higher, 40°C or higher, or even 50°C or higher. On the other hand, if ΔT is 200°C or lower, adjustment of the glass composition becomes easier. ΔT can be 200°C or lower, or 180°C or lower, 160°C or lower, or even 90°C or lower. The devitrification temperature is the temperature at which crystals form in the molten glass base and begin to grow. ΔT is, for example, 20°C or higher and 90°C or lower.

[0073] Among glass fibers, long glass fibers are produced, for example, by drawing out a molten glass base from a nozzle in a bushing installed at the bottom of a kiln, continuously winding it on a winder, and spinning it into a fibrous form. Short glass fibers are produced, for example, by pouring the molten glass base from the bottom of a kiln into a spinner rotating at high speed, and then drawing the fibrous glass that has been ejected from holes in the side of the spinner by centrifugal force further thinly using pressure such as a gas jet. Glass flakes are also produced from molten glass by methods such as the blowing method and the cup method. The same is true for powdered glass. Taking these production processes into consideration, it is desirable for a glass composition to have excellent melting properties and good formability, appropriate temperature-viscosity characteristics, and a devitrification temperature lower than the working temperature.

[0074] (Young's Modulus) The higher the Young's modulus of the glass composition forming the glass product, the better its elasticity, and the improved mechanical properties of resin composites reinforced with the glass product, including glass fiber reinforced plastics. Here, Young's modulus (GPa) can be determined by measuring the longitudinal wave velocity and shear wave velocity of elastic waves propagating through the glass using a conventional ultrasonic method, and then separately measuring the density of the glass using the Archimedes method. The lower limit of this Young's modulus can be 75 GPa or more, 85 GPa or more, 86 GPa or more, 87 GPa or more, 88 GPa or more, or even 89 GPa or more. The upper limit of Young's modulus is preferably 100 GPa or less, 99 GPa or less, 98 GPa or less, 97 GPa or less, 96 GPa or less, or even 95 GPa or less.

[0075] (Chemical Durability) Acid resistance, water resistance, and alkali resistance are suitable indicators of chemical durability in reinforcement applications of resin composites. The mass loss rate ΔW1, described below, is used as an indicator of acid resistance, with a smaller ΔW1 indicating higher acid resistance. When glass fibers or other glass products are used to reinforce plastics, the ΔW1 of the glass product is preferably 5.0% by mass or less. Therefore, ΔW1 can be 5.0% by mass or less, 4.0% by mass or less, 3.0% by mass or less, 2.0% by mass or less, 1.5% by mass or less, 1.2% by mass or less, 1.0% by mass or less, 0.9% by mass or less, 0.8% by mass or less, 0.7% by mass or less, 0.6% by mass or less, 0.5% by mass or less, 0.4% by mass or less, or even 0.35% by mass or less. ΔW1 achieved by this embodiment is, for example, 0.01 to 5.0% by mass. The mass loss rate ΔW2, described below, is used as an indicator of water resistance, with a smaller mass loss rate ΔW2 indicating higher water resistance. When glass fiber or other glass products are used to reinforce plastics, the ΔW2 of the glass product is preferably less than 0.50% by mass. ΔW2 can be less than 0.5% by mass, or can be 0.45% by mass or less, 0.4% by mass or less, 0.35% by mass or less, 0.3% by mass or less, 0.25% by mass or less, or even 0.2% by mass or less. ΔW2 that can be achieved by this embodiment is, for example, 0.01% by mass or more and less than 0.50% by mass.

[0076] The acid resistance and water resistance of the glass composition can also be used as indicators. The mass loss rate ΔW, described below, is used as an indicator of acid resistance, with a smaller ΔW indicating higher acid resistance. The ΔW of the glass composition is preferably 7.0 mass% or less. Therefore, ΔW can be less than 7.0 mass%, or can be 5.0 mass% or less, 2.0 mass% or less, 1.0 mass% or less, 0.8 mass% or less, 0.6 mass% or less, 0.5 mass% or less, 0.4 mass% or less, 0.3 mass% or less, 0.25 mass% or less, or even 0.2 mass% or less. The ΔW that can be achieved by this embodiment is, for example, 0.01 to 7.0 mass%. The alkali elution amount, described below, is used as an indicator of water resistance, with a smaller value indicating higher water resistance. The alkali elution amount of the glass composition is preferably less than 5.0 mass%. The amount of alkali elution may be less than 3.0% by mass, or may be 1.0% by mass or less, 0.5% by mass or less, 0.3% by mass or less, 0.25% by mass or less, 0.2% by mass or less, or even 0.15% by mass or less. The amount of alkali elution that can be achieved by this embodiment is, for example, 0.01% by mass or more and less than 5.0% by mass.

[0077] Glass products made of such glass having excellent chemical durability can be suitably used for glass fiber reinforced plastics and the like.

[0078] (Refractive Index) Refractive index n of the glass composition D The refractive index n may be, for example, 1.525 to 1.600. D is the refractive index at a wavelength of 589.3 nm. D may be, for example, 1.525 or more, 1.530 or more, 1.535 or more, 1.540 or more, 1.545 or more, 1.550 or more, or even 1.555 or more, and may be 1.600 or less, 1.595 or less, 1.590 or less, 1.585 or less, or even 1.580 or less. D and the n of the resin used D The difference Δn D is desirably small, and may be, for example, 0.010 or less, 0.005 or less, 0.003 or less, or even 0.002 or less.

[0079] Refractive index n of the glass composition C The refractive index n may be, for example, 1.520 to 1.595. c is the refractive index at a wavelength of 656.3 nm. C may be, for example, 1.520 or more, 1.525 or more, 1.530 or more, 1.535 or more, 1.540 or more, 1.545 or more, or even 1.550 or more, or may be 1.595 or less, 1.590 or less, 1.585 or less, 1.580 or less, or even 1.575 or less. C and the n of the resin used C The difference Δn C is desirably small, and may be, for example, 0.010 or less, 0.005 or less, 0.003 or less, or even 0.002 or less.

[0080] <Glass Product> The glass product of the present embodiment can function as a reinforcing material, more specifically, as a reinforcing material for a resin composite material. The shape of the glass product is not particularly limited, and may be, for example, at least one type selected from the group consisting of glass fiber and glass filler.

[0081] (Glass Fiber) The glass fiber of this embodiment is composed of the glass composition described above. The glass fiber of this embodiment may be either long glass fiber or short glass fiber. Long glass fiber is produced by causing a viscosity-controlled glass melt to flow out of a nozzle and winding it up with a winder. This continuous fiber is cut to an appropriate length when used. Short glass fiber is produced by blowing off the glass melt with high-pressure air, centrifugal force, or the like. Short glass fiber is sometimes called glass wool because it has a cotton-like form.

[0082] The average fiber diameter of the glass fibers is, for example, 0.1 to 50 μm. The average fiber diameter of the glass fibers may be 0.1 μm or more, 0.2 μm or more, 0.3 μm or more, 0.4 μm or more, or even 0.5 μm or more, and may be 50 μm or less, 40 μm or less, 30 μm or less, or 25 μm or less. In the case of long glass fibers, the average fiber diameter may be 1 μm or more, 2 μm or more, 3 μm or more, 4 μm or more, or even 5 μm or more. In the case of short glass fibers, the average fiber diameter may be 10 μm or less, 5 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, or even 1 μm or less.

[0083] The glass fiber may be, for example, at least one type selected from the group consisting of roving, roving cloth, continuous strand mat, milled fiber, filament mat, chopped strand, yarn, glass cloth, and glass tape, particularly at least one type selected from the group consisting of roving, roving cloth, continuous strand mat, filament mat, yarn, glass cloth, and glass tape.

[0084] (Glass Filler) The glass filler has a shape that does not fall under the category of glass fiber. The glass filler may be, for example, at least one type selected from the group consisting of glass flakes and glass powder.

[0085] Glass flakes, also known as flake glass, have a flake-like shape. The average thickness of glass flakes is, for example, 0.1 to 15 μm, and even 0.3 to 10 μm. The thickness of glass flakes corresponds to the distance t between the two main surfaces of the glass flakes 10. The average particle size of glass flakes is, for example, 0.2 to 15,000 μm. The aspect ratio of glass flakes is, for example, 2 to 1,000. The aspect ratio can be determined by dividing the average particle size by the average thickness. The average thickness can be determined by measuring the thickness t of 100 or more glass flakes using a scanning electron microscope (SEM) and calculating the average value. The average particle size of glass flakes can be determined by the particle size (D50) corresponding to a cumulative deposition percentage of 50% in the particle size distribution measured by a laser diffraction scattering method. Glass flakes can be obtained by known methods such as the blowing method and the cup method. The glass flakes may have the shape of very thin flakes. Powdered glass, also called glass beads or glass powder, has a particulate shape. Powdered glass is produced, for example, by crushing glass. The average particle size of the glass powder is, for example, 0.1 to 500 μm, or preferably 1 to 100 μm. The particle size of powdered glass is defined as the diameter of a sphere having the same volume.

[0086] <Resin Composite Material> The resin composite material of this embodiment includes a reinforcing material such as the glass fiber described above. That is, the resin composite material of this embodiment is reinforced by the reinforcing material. The resin composite material may be, for example, glass fiber reinforced plastic (GFRP) or long glass fiber mat reinforced thermoplastic (GMT). The resin contained in the resin composite material may be, but is not limited to, polyester resin, vinyl ester resin, epoxy resin, phenolic resin, etc. The resin composite material may also include additives other than the resin and reinforcing material.

[0087] Specific examples of resins suitable for resin composites are listed below: polyethylene, polyamide (nylon), polyvinyl chloride, methyl methacrylate-styrene copolymer, epoxy resin, acrylonitrile-styrene copolymer, polydiallyl phthalate, polyethylene terephthalate, amorphous polyarylate, polycarbonate, polystyrene, polyvinylidene chloride, polyacrylonitrile, polymethacrylonitrile, poly(1,3-butadiene), butadiene-acrylonitrile copolymer, polymethylisopropenyl ketone, polyisoprene, poly[(N-2-methoxyethyl)methacrylamide], chloride Vinyl-vinyl acetate copolymer, poly(1,3-dichloropropyl methacrylate), poly[2-chloro-1-(chloromethyl)ethyl methacrylate], polyacrolein, poly(1-vinyl-2-pyrrolidone), poly(N-methylmaleimide-alt-isobutene), poly(cyclohexyl-α-chloroacrylate), poly(2-chloroethyl-α-chloroacrylate), butadiene-styrene copolymer, poly(2-aminoethyl methacrylate), polyfurfuryl methacrylate, polybutyl mercaptyl methacrylate, poly(1 -phenyl-n-amyl methacrylate), poly(N-methyl methacrylamide), urea resin, poly(sec-butyl-α-bromoacrylate), poly(cyclohexyl-α-bromoacrylate), polybromoethyl methacrylate, polyethyl mercaptyl methacrylate, poly(N-allyl methacrylamide), poly(1-phenylethyl methacrylate), poly(2-vinyltetrahydrofuran), polyvinylfuran, poly(methyl-m-chlorophenylethylsiloxane), poly(p-methoxybenzyl methacrylate) acrylate), polyisopropyl methacrylate, poly(p-isopropylstyrene), poly(p,p'-xylenyl dimethacrylate), polycyclohexylmethylsilane, poly(1-phenylallyl methacrylate), poly(p-cyclohexylphenyl methacrylate), poly(2-phenylethyl methacrylate), poly(methyl m-chlorophenylsiloxane), poly[4,4-heptane bis(4-phenyl)carbonate], poly[1-(o-chlorophenyl)ethyl methacrylate], poly[oxycarbonyloxy-1,4-phenylene-1-propylbutylidene-1,4-phenylene], styrene-maleic acid copolymer, poly(1-phenylcyclohexyl methacrylate), poly(2,2,2'-trimethylhexamethylene terephthalamide), poly(oxycarbonyloxy-1,4-phenylene-1,3-dimethylbutylidene-1,4-phenylene), poly(methyl α-bromoacrylate), poly(benzyl methacrylate), poly[2-(phenylsulfonyl)ethyl methacrylate], poly(m-cresyl methacrylate), poly(oxycarbonyloxy -1,4-phenyleneisobutylidene-1,4-phenylene), poly(o-methoxyphenyl methacrylate), poly(phenyl methacrylate), poly(o-cresyl methacrylate), poly(2,3-dibromopropyl methacrylate), poly(oxycarbonyloxy-1,4-phenylene-1-methyl-butylidene-1,4-phenylene), poly(oxy-2,6-dimethylphenylene), polyvinyl benzoate, poly[2,2-propane bis[4-(2-methylphenyl)]carbonate], poly(oxycarbonyloxy-1,4-phenylene butylidene-1,4-phenylene), poly[1,1-butane bis(4-phenyl)carbonate], poly(1,2-diphenylethyl methacrylate), poly(o-chlorobenzyl methacrylate), poly(oxycarbonyloxy-1,4-phenylene-sec-butylidene-1,4-phenylene), poly(oxypentaerythritol oxyphthaloyl), poly(m-nitrobenzyl methacrylate), poly(oxycarbonyloxy-1,4-phenyleneisopropylidene-1,4-phenylene), poly[N-(2-phenylethyl)methacrylate amide], poly[1,1-cyclohexane bis[4-(2,6-dichlorophenyl)]carbonate], poly(4-methoxy-2-methylstyrene), poly(o-methylstyrene), poly[2,2-propane bis[4-(2-chlorophenyl)]carbonate], poly[1,1-cyclohexane bis(4-phenyl)carbonate], poly(oxycarbonyloxy-1,4-phenylenecyclohexylidene-1,4-phenylene), poly(o-methoxystyrene), poly(diphenylmethyl methacrylate), poly(oxycarbonyloxy-1,4-phenyleneethylidene-1,4-phenylene), poly[1,1-ethane bis(4-phenyl)carbonate], polypropylene sulfide, poly(p-bromophenyl methacrylate), poly(N-benzyl methacrylamide), poly(p-methoxystyrene), poly(4-methoxystyrene), poly[1,1-cyclopentane bis(4-phenyl)carbonate], poly(o-chlorodiphenylmethyl methacrylate).

[0088] As mentioned above, in a resin composite, it is desirable that the difference between the refractive index of the glass product, which is the reinforcing material, and the refractive index of the resin is small. The smaller the difference between the refractive index of the glass product and the refractive index of the resin, the less light is scattered at the interface between the glass product and the resin, so the transparency of the resin can be maintained and the light transmittance of the resin composite increases. The refractive index n of the resin D Examples are shown in Table 1. The refractive index of the resin can be adjusted by copolymerization with an appropriate monomer.

[0089]

[0090] Hereinafter, the embodiments of the present invention will be described in more detail with reference to Examples and Comparative Examples. (Examples and Comparative Examples) Conventional glass raw materials such as silica sand were mixed to obtain the compositions shown in Tables 2 to 6, and batches of glass raw materials were prepared for each Example and Comparative Example. Each batch was heated to 1500 to 1600°C using an electric furnace to melt it, and maintained in this state for approximately 4 hours until the composition became uniform. Thereafter, a portion of the molten glass (glass melt) was poured onto an iron plate and slowly cooled to room temperature in the electric furnace to obtain a bulk glass composition (plate-shaped product, glass sample).

[0091] The evaluation method of the properties is explained below. (Working Temperature) The relationship between viscosity and temperature of the obtained glass composition was investigated by a conventional platinum sphere pulling method, and the working temperature was determined from the results. Here, the platinum sphere pulling method is a method of measuring viscosity by applying the relationship between the load (resistance) applied when immersing a platinum sphere in molten glass and pulling the platinum sphere up at a uniform speed, and the gravity and buoyancy acting on the platinum sphere, to Stokes' law, which shows the relationship between the viscosity and the falling speed of microparticles when they settle in a fluid.

[0092] (Devitrification Temperature) A glass composition pulverized to particle diameters of 1.0 to 2.8 mm was placed in a platinum boat and held for 2 hours in an electric furnace equipped with a temperature gradient (800 to 1400°C). The devitrification temperature was determined from the maximum temperature of the electric furnace corresponding to the position where crystals appeared. When the glass became cloudy and crystals could not be observed, the maximum temperature of the electric furnace corresponding to the position where cloudiness appeared was taken as the devitrification temperature. Here, the particle diameter is a value measured by a sieving method. Note that the temperature (temperature distribution within the electric furnace), which varies depending on the location within the electric furnace, was measured in advance, and the glass composition placed in a predetermined location within the electric furnace was heated at the temperature of the predetermined location measured in advance. The temperature difference ΔT is the temperature difference obtained by subtracting the devitrification temperature from the working temperature.

[0093] (Young's modulus) Young's modulus E is calculated by measuring the longitudinal wave velocity vl and the shear wave velocity vt of elastic waves propagating through glass using a conventional ultrasonic method, and then calculating E = 3ρ v from the density ρ of the glass measured separately using the Archimedes method. t 2 ・(v l 2 -4 / 3・v t 2 ) / (v l 2 -v t 2 ) was calculated using the formula:

[0094] (Tensile Modulus) A glass fiber (filament) was produced using the obtained glass composition (bulk). That is, the glass composition (bulk) was remelted in an electric furnace and then formed into pellets while cooling. A glass fiber having a diameter of 15 μm was produced using these pellets. The tensile modulus of the obtained glass fiber was measured by a method in accordance with "Test method for tensile properties of carbon fiber single fiber R7606:2000" of the Japanese Industrial Standards (JIS).

[0095] (Chemical durability) Acid resistance ΔW The mass loss rate ΔW of the glass composition was measured according to the Japan Optical Glass Industry Association Standard (JOGIS) "Method for measuring the chemical durability of optical glass (powder method) 06-2019." The glass powder obtained by pulverizing the glass sample was sieved by sieving. Specifically, glass powder of a size that passed through a 710 μm auxiliary mesh sieve and a 600 μm standard mesh sieve, but not through a 425 μm standard mesh sieve, as specified in JIS Z 8801, was taken in an amount of grams equal to the specific gravity of the glass. The mass loss rate when this glass powder was immersed in 100 mL of a 10% by weight sulfuric acid aqueous solution at 80°C for 72 hours was determined, and this mass loss rate was defined as ΔW. Here, a 10% by weight sulfuric acid aqueous solution was used instead of the 0.01 N (mol / L) nitric acid aqueous solution used in the JOGIS measurement method. The temperature of the sulfuric acid aqueous solution was 80°C, and the volume was 100 mL instead of 80 mL in the JOGIS measurement method. Furthermore, the treatment time was 72 hours instead of 60 minutes in the JOGIS measurement method. Alkali elution amount: The alkali elution amount was measured according to the Japanese Industrial Standards (JIS) "Test Methods for Glass Apparatus for Chemical Analysis R 3502-1995." The glass powder obtained by crushing the glass sample was sieved through a standard mesh sieve specified in JIS Z 8801. The glass powder that passed through a standard mesh sieve with a 420 μm mesh size and remained on a standard mesh sieve with a 250 μm mesh size was weighed out in grams equal to the specific gravity of the glass. This glass powder was immersed in 50 mL of distilled water at 100°C for 1 hour, and the alkali components in this aqueous solution were titrated with 0.01 N sulfuric acid. The number of milliliters of 0.01N sulfuric acid required for titration was multiplied by 0.31 to determine the number of milligrams of alkali components converted to Na2O, and this number was taken as the alkali elution amount. A smaller amount of alkali elution indicates higher water resistance. - Acid resistance ΔW1 A glass fiber with a diameter of 15 μm was cut into a length of 20 mm and weighed in grams equal to the specific gravity of the glass. This glass fiber was immersed in 100 mL of 10% by weight aqueous sulfuric acid at 80°C for 24 hours, and the mass loss rate was determined, and this mass loss rate was taken as ΔW1.Water resistance ΔW2 A glass fiber having a diameter of 15 μm was cut into a length of 20 mm, and an amount equal to the specific gravity of the glass was weighed out. The glass fiber was immersed in 100 mL of distilled water at 80°C for 24 hours to determine the mass loss rate, which was designated as ΔW2. The mass loss rate was calculated using the following formula, where Wa is the mass before immersion and Wb is the mass after immersion: Mass loss rate (%) = {(Wa - Wb) / Wa} x 100.

[0096] (Refractive Index) The refractive index n of the glass composition at the red hydrogen C line (wavelength of light: 656.3 nm) was measured using an Abbe refractometer. C , the refractive index n of the yellow sodium D line (wavelength of light 589.3 nm) D was measured.

[0097] The results of these measurements are shown in Tables 2 to 6. Note that the glass compositions in the tables are all values ​​expressed in mass %.

[0098]

[0099]

[0100]

[0101]

[0102]

[0103] From Examples 1 to 48, Young's modulus was 84 to 93 GPa, tensile modulus was 76 to 88 GPa, working temperature was 1210 to 1288°C, ΔT (working temperature - devitrification temperature) was 2 to 88°C, ΔW was 0.10 to 0.96, alkali elution amount was 0.07 to 0.18, refractive index n C 1.535-1.575, n D The results obtained were 1.539 to 1.578 mass%, ΔW1 0.25 to 2.61 mass%, and ΔW2 0.16 to 0.46 mass%.

[0104] The glass composition of Comparative Example 1 has a C-glass composition. C-glass is inferior in Young's modulus and tensile modulus. The glass composition of Comparative Example 2 has an E-glass composition. E-glass is inferior in acid resistance and also slightly inferior in Young's modulus and tensile modulus. C-glass and E-glass have a high B2O3 content, which may affect manufacturing equipment. The glass composition of Comparative Example 3 has an S-glass composition. S-glass has a high working temperature and a negative ΔT, making it somewhat inferior in mass productivity.

[0105] Furthermore, glass flakes having a thickness of 0.5 to 1 μm and an average particle size of 100 to 500 μm were produced by a blowing method using the glass compositions of Examples 1 to 32 and 35 to 48. Similarly, glass long fibers having a diameter of 15 μm were crushed using the glass compositions of Examples 1 to 32 and 35 to 48 to produce milled fibers having an average fiber length of 50 to 250 μm. The refractive index n D The results are shown in Tables 7 and 8. As shown in Table 7, the glass flakes of Examples 49 to 94 were measured for refractive indexes n D As shown in Table 8, the milled fibers of Examples 95 to 140 had a refractive index of n D Results ranged from 1.533 to 1.572.

[0106]

[0107]

Claims

1. A glass product for resin composites, comprising: Expressed in mass %, 55≦SiO 2 ≦70、 0≦B 2 O 3 20 5≦Al 2 O 3 ≦15、 47≦(SiO) 2 -Al 2 Oh 3 )≦60、 0.1≦MgO≦10, 10≦CaO≦30, 0≦ZnO≦2, 0≦(L) 2 O+1 2 O+K 2 O)≦4、 A glass product comprising a glass composition containing the components:

2. 2. The glass product according to claim 1, wherein the glass product is at least one selected from the group consisting of glass fiber and glass filler.

3. The glass composition contains BaO and F 2 3. The glass product according to claim 1, which is substantially free of:

4. The glass composition has a content of SiO in terms of mass% of 55 or less. 2 3. The glass product of claim 1, wherein the glass contains ≦67% of the components.

5. The glass composition has a content of SiO in terms of mass% of 55 or less. 2 5. The glass product of claim 4, wherein the composition is ≦65.

6. The glass composition has, in mass %, 8≦Al 2 O 3 3. The glass product of claim 1, wherein the glass contains ≦15 components.

7. The glass composition has a content of 47≦(SiO 2 -Al 2 O 3 3. The glass product according to claim 1, wherein the glass contains 57% or more of the components.

8. 3. The glass product according to claim 1, wherein the glass composition contains components in the range of 1 to 5 mass %.

9. 3. The glass product according to claim 1, wherein the glass composition contains, in mass %, 15≦CaO≦30.

10. The glass composition has a content of 0≦(Li 2 O + Na 2 O+K 2 3. The glass product according to claim 1, further comprising:

11. The glass composition has a content of 0≦TiO in mass %. 2 3. The glass product of claim 1, wherein the glass contains ≦5 components.

12. The glass composition has a content of 0≦ZrO in mass %. 2 3. The glass product according to claim 1 or 2, containing the component:

13. The glass composition has a content of 0≦ZrO in mass %. 2 13. The glass product of claim 12, wherein the glass contains a component of ≦0.

5.

14. The glass composition has a content of 0≦T-Fe, expressed in mass %. 2 O 3 3. The glass product of claim 1, wherein the glass contains ≦5 components. However, T-Fe 2 O 3 is Fe 2 O 3 is the total iron oxides converted to

15. The glass composition has a content of 0≦T-Fe, expressed in mass %. 2 O 3 3. The glass product according to claim 1, wherein the glass contains a component of ≦0.

5.

16. The glass composition has a content of 0≦T-Fe, expressed in mass %. 2 O 3 16. The glass product of claim 15, containing a component of <0.

1.

17. 3. The glass product according to claim 1, wherein the glass composition is substantially free of ZnO.

18. The glass composition comprises TiO 2 3. The glass product according to claim 1, which is substantially free of:

19. The glass composition is B 2 O 3 3. The glass product according to claim 1, which is substantially free of:

20. 3. The glass product according to claim 1, wherein the glass composition is substantially free of SrO.

21. The glass composition comprises ZrO 2 3. The glass product according to claim 1, which is substantially free of:

22. 3. The glass product according to claim 1, wherein the working temperature is 1300°C or less when the temperature at which the viscosity of the glass composition is 1000 dPa·sec is defined as the working temperature.

23. 3. The glass product according to claim 1, wherein, when a temperature at which the viscosity of the glass composition is 1000 dPa·sec is defined as a working temperature, a temperature difference ΔT obtained by subtracting a devitrification temperature from the working temperature is 0°C or more.

24. 3. The glass product according to claim 1, wherein the working temperature is 1200 to 1300° C. when the temperature at which the viscosity of the glass composition is 1000 dPa·sec is defined as the working temperature.

25. 24. The glass product according to claim 23, wherein the ΔT (working temperature - devitrification temperature) is 2 to 90°C.

26. 3. The glass product of claim 2, which is glass fiber.

27. 3. The glass product of claim 2, which is a glass filler.

28. 27. The glass product according to claim 26, which is at least one selected from the group consisting of roving, roving cloth, continuous strand mat, milled fiber, filament mat, chopped strand, yarn, glass cloth and glass tape.

29. 28. The glass product according to claim 27, wherein the glass filler is at least one selected from the group consisting of glass flakes and glass powder.

30. A resin composite material comprising the glass product according to claim 1 or 2.