Glass material

Abstract

Provided in the present invention is a glass material, which comprises the following components in percentages by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; and SrO: 2-15%. By means of a rational component design, the glass material obtained in the present invention has relatively high light transmittance.

Description

Glass material

[0001] The present application claims priority to the Chinese patent application No. 202411314581.6, filed on September 20, 2024, and entitled "Glass material", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to a glass material, in particular to a glass material with high light transmittance. BACKGROUND

[0003] In recent years, with the continuous integration of optical and electronic information science, life science and new material science, the application of glass materials as optoelectronic basic materials in the fields of optical transmission, optical storage and optoelectronic display has made rapid progress. Optical instruments and equipment are developing rapidly in terms of digitization, integration and high precision, and higher performance requirements are put forward for glass materials used in optical instruments and equipment.

[0004] With the rapid development of large field of view high resolution endoscope system, large numerical aperture low absorption optical fiber and other technologies, as the core material of optical fiber, the glass needs higher refractive index to achieve larger numerical aperture, and the core material glass needs high transmittance to achieve low light absorption under the condition of 3-5 meters light path. In the prior art, high content of PbO is added to the glass material to achieve the above performance, but with the requirements of environmental protection policy and the improvement of health consciousness, lead-containing glass cannot meet the requirements of environmental protection. Patent document CN101389575A discloses a glass with a refractive index of 1.55-1.69 and an Abbe number of 55-65, which does not contain PbO, but contains 46-70wt% of B2O3. Excessive B2O3 will increase the difficulty of glass forming and easily produce stripes. Patent document CN1215032A discloses a glass with a refractive index of 1.55-1.63 and an Abbe number of 55-63, which contains 45-50wt% of SiO2. Excessive SiO2 will increase the melting temperature and high temperature viscosity of the glass, which is not conducive to improving the light transmittance of the glass. SUMMARY

[0005] Based on the above reasons, the technical problem to be solved by the present application is to provide a glass material with high light transmittance.

[0006] The technical solution adopted by the present application to solve the technical problem is:

[0007] The glass material contains, in terms of weight percentage, SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; and SrO: 2-15%.

[0008] Further, the glass material, the components of which are expressed in percentage by weight, further comprises: Al2O3: 0-10%; and / or ZrO2: 0-10%; and / or Gd2O3: 0-8%; and / or Y2O3: 0-8%; and / or Yb2O3: 0-5%; and / or Nb2O5: 0-5%; and / or WO3: 0-5%; and / or ZnO: 0-4.5%; and / or Rn2O: 0-6.5%; and / or MgO: 0-5%; and / or CaO: 0-4%; and / or TiO2: 0-5%; and / or Ta2O5: 0-5%; and / or P2O5: 0-4%; and / or F: 0-5%; and / or fining agent: 0-1%, the Rn2O being one or more of Li2O, Na2O, K2O, and the fining agent being one or more of Sb2O3, SnO2, SnO, CeO2.

[0009] The glass material, the components of which are expressed in percentage by weight, consists of SiO2: 17-32%; B2O3: 18-32%; Ln2O3: 7.5-28%, preferably Ln2O3: 10-25%, more preferably Ln2O3: 11-20%, the Ln2O3 being the total content of La2O3, Gd2O3, Y2O3, Yb2O3; BaO: 12-27.5%; SrO: 2-15%; Al2O3: 0-10%; ZrO2: 0-10%; Gd2O3: 0-8%; Y2O3: 0-8%; Yb2O3: 0-5%; Nb2O5: 0-5%; WO3: 0-5%; ZnO: 0-4.5%; Rn2O: 0-6.5%; MgO: 0-5%; CaO: 0-4%; TiO2: 0-5%; Ta2O5: 0-5%; P2O5: 0-4%; F: 0-5%; fining agent: 0-1%, the Rn2O being one or more of Li2O, Na2O, K2O, and the fining agent being one or more of Sb2O3, SnO2, SnO, CeO2.

[0010] Further, the glass material, the components of which are expressed in percentage by weight, wherein: B2O3 / SiO2 is 0.7-1.7, preferably B2O3 / SiO2 is 0.75-1.5, more preferably B2O3 / SiO2 is 0.8-1.3, further preferably B2O3 / SiO2 is 0.85-1.1.

[0011] Further, the glass material, the components of which are expressed in percentage by weight, wherein: B2O3 / SiO2 is 0.7-1.7, preferably B2O3 / SiO2 is 0.75-1.5, more preferably B2O3 / SiO2 is 0.8-1.3, further preferably B2O3 / SiO2 is 0.85-1.1.

[0012] Further, the glass material, the components of which are expressed in percentage by weight, wherein: (La2O3+SrO) / BaO is 0.5-2.5, preferably (La2O3+SrO) / BaO is 0.7-2.0, more preferably (La2O3+SrO) / BaO is 0.8-1.8, further preferably (La2O3+SrO) / BaO is 0.9-1.5.

[0013] Further, the glass material, the components of which are expressed in percentage by weight, wherein: SrO / La2O3 is 0.1-1.5, preferably SrO / La2O3 is 0.2-1.2, more preferably SrO / La2O3 is 0.3-1.0, further preferably SrO / La2O3 is 0.35-0.8.

[0014] Further, the glass material, the components of which are expressed in percentage by weight, wherein: La2O3 / SiO2 is 0.3-1.2, preferably La2O3 / SiO2 is 0.35-1.0, more preferably La2O3 / SiO2 is 0.4-0.9, further preferably La2O3 / SiO2 is 0.45-0.8.

[0015] Further, the glass material, the components of which are expressed in percentage by weight, wherein: (BaO+SrO) / (ZrO2+Al2O3) is 1.0-15.0, preferably (BaO+SrO) / (ZrO2+Al2O3) is 1.5-10.0, more preferably (BaO+SrO) / (ZrO2+Al2O3) is 2.0-8.0, further preferably (BaO+SrO) / (ZrO2+Al2O3) is 2.5-5.0.

[0016] Further, the glass material, the components of which are expressed in percentage by weight, wherein: Al2O3 / B2O3 is 0.01-0.45, preferably Al2O3 / B2O3 is 0.05-0.4, more preferably Al2O3 / B2O3 is 0.1-0.3.

[0017] Further, the glass material, the components of which are expressed in percentage by weight, wherein: ZrO2 / SiO2 is 0.01-0.4, preferably ZrO2 / SiO2 is 0.05-0.35, more preferably ZrO2 / SiO2 is 0.1-0.3.

[0018] Further, the glass material, the components of which are expressed in percentage by weight, wherein: Al2O3 / ZrO2 is 0.2-8.0, preferably Al2O3 / ZrO2 is 0.5-6.0, more preferably Al2O3 / ZrO2 is 0.8-4.0, further preferably Al2O3 / ZrO2 is 1.0-2.0.

[0019] Further, the glass material, the components of which are expressed in percentage by weight, wherein: (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 1.0 or less, preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 0.8 or less, more preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 0.5 or less, further preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 0.3 or less, the Rn2O being one or more of Li2O, Na2O, K2O.

[0020] Further, the glass material, the components of which are expressed in percentage by weight, wherein: (ZnO+CaO+Rn2O) / La2O3 is 1.0 or less, preferably (ZnO+CaO+Rn2O) / La2O3 is 0.8 or less, more preferably (ZnO+CaO+Rn2O) / La2O3 is 0.5 or less, further preferably (ZnO+CaO+Rn2O) / La2O3 is 0.3 or less, the Rn2O being one or more of Li2O, Na2O, K2O.

[0021] Further, the glass material, the components of which are expressed in percentage by weight, wherein: SiO2: 21-30%, preferably SiO2: 22-28%; and / or B2O3: 21-30%, preferably B2O3: 22-29%; and / or La2O3: 11-20%, preferably La2O3: 12-18%; and / or BaO: 15-25%, preferably BaO: 16-23%; and / or SrO: 3-13%, preferably SrO: 5.5-11%; and / or Al2O3: 1-8%, preferably Al2O3: 2-7%; and / or ZrO2: 0.5-8%, preferably ZrO2: 1-7%; and / or Gd2O3: 0-5%, preferably Gd2O3: 0-1.5%, more preferably free of Gd2O3; and / or Y2O3: 0-5%, preferably Y2O3: 0-1.5%, more preferably free of Y2O3; and / or Yb2O3: 0-3%, preferably Yb2O3: 0-2%, more preferably free of Yb2O3; and / or Nb2O5: 0-3%, preferably Nb2O5: 0-1%, more preferably free of Nb2O5; and / or WO3: 0-3%, preferably WO3: 0-1%, more preferably free of WO3; and / or ZnO: 0-3%, preferably ZnO: 0-2%, more preferably free of ZnO; and / or Rn2O: 0-5%, preferably Rn2O: 0-2%; and / or MgO: 0-3%, preferably MgO: 0-2%, more preferably free of MgO; and / or CaO: 0-3%, preferably CaO: 0-2%, more preferably free of CaO; and / or TiO2: 0-3%, preferably TiO2: 0-2%, more preferably free of TiO2; and / or Ta2O5: 0-3%, preferably Ta2O5: 0-1%, more preferably free of Ta2O5; and / or P2O5: 0-2%, preferably P2O5: 0-1%, more preferably free of P2O5; and / or F: 0-3%, preferably F: 0-2%, more preferably free of F; and / or fining agent: 0-0.5%, preferably fining agent: 0-0.2%, the Rn2O being one or more of Li2O, Na2O, K2O, and the fining agent being one or more of Sb2O3, SnO2, SnO, CeO2.

[0022] Further, the glass material, the components of which are expressed in percentage by weight, wherein: Li2O: 0-5%, preferably Li2O: 0-3%, more preferably Li2O: 0-2%; and / or Na2O: 0-5%, preferably Na2O: 0-3%, more preferably Na2O: 0-2%, further preferably free of Na2O; and / or K2O: 0-5%, preferably K2O: 0-3%, more preferably K2O: 0-2%, further preferably free of K2O.

[0023] Further, the glass material has an average light transmittance τ in the range of 400 to 800 nm of 99.0% or more, preferably 99.5% or more, more preferably 99.7% or more 400～800nm Further, the glass material has an average light transmittance τ in the range of 400 to 800 nm of 99.0% or more, preferably 99.5% or more, more preferably 99.7% or more 400nm Further, the glass material has an average light transmittance τ in the range of 400 to 800 nm of 99.0% or more, preferably 99.5% or more, more preferably 99.7% or more

[0024] Further, the glass material has a thickness of 1 to 12 mm, preferably 2 to 12 mm, more preferably 5 to 10 mm, further preferably 2 mm or 5 mm or 8 mm or 10 mm.

[0025] Further, the glass material has a refractive index n d Further, the glass material has a refractive index n d of 1.59 to 1.66, preferably 1.60 to 1.65, more preferably 1.61 to 1.64; and / or an Abbe number v d of 55 to 61, preferably 56 to 60, more preferably 57 to 59; and / or a transition temperature T g of 650°C or less, preferably 600 to 650°C, more preferably 605 to 645°C, further preferably 610 to 640°C; and / or a water resistance stability D W of 3 or more, preferably 2 or more, more preferably 1; and / or a density p of 3.60 g / cm 3 or less, preferably 3.50 g / cm 3 or less, more preferably 3.40 g / cm 3 or less; and / or a Knoop hardness H K of 500 x 10 7 Pa or more, preferably 515 x 10 7 Pa or more, more preferably 530 x 10 7 Pa or more; and / or a Young's modulus E of 7000 x 10 7 Pa or more, preferably 7300 x 10 7 Pa or more, more preferably 7600 x 10 7 Pa or more; and / or an abrasion degree F A of 200 or less, preferably 175 or less, more preferably 150 or less; and / or a thermal expansion coefficient a 20 / 300℃ of 90 x 10 -7 / K or less, preferably 50 x 10 -7 / K to 85 x 10 -7 / K, more preferably 55 x 10 -7 / K to 80 x 10 -7 / K, further preferably 60 x 10 -7 / K to 72 x 10-7 a high temperature viscosity of 1200°C of 60 dPaS or less, preferably 40 dPaS or less, more preferably 30 dPaS or less; and / or an anti-crystallization property of B class or more, preferably A class.

[0026] A glass preform made of the above glass material.

[0027] A glass element made of the above glass material or the above glass preform.

[0028] An optical instrument containing the above glass material or containing the above glass element.

[0029] The present application has the beneficial effect that the glass material obtained by the present application has a high light transmittance by a rational component design. DETAILED DESCRIPTION

[0030] Hereinafter, the embodiments of the glass material of the present application will be described in detail, but the present application is not limited to the following embodiments, and can be implemented by appropriately changing within the scope of the object of the present application. Further, as for the repeatedly described parts, although there are appropriately omitted descriptions, the gist of the present application is not limited thereby. In the following, the glass material of the present application is sometimes referred to as glass.

[0031] [GLASS MATERIAL]

[0032] Hereinafter, the range of each component of the glass material of the present application will be described. In the present specification, if not otherwise specified, the content of each component, the total content, and the entire content are all expressed in terms of weight percentage with respect to the total amount of glass material converted into an oxide composition. Here, the "converted into an oxide composition" means that, in the case where the oxide, the composite salt, and the hydroxide, etc. used as raw materials for the composition components of the glass material of the present application are decomposed and converted into an oxide at the time of melting, the total amount of the oxide is taken as 100%.

[0033] Unless otherwise indicated in a specific case, the numerical ranges set forth herein include the upper and lower limits, "and / or" includes both conjunctive and disjunctive, and all integers and fractions within the range, and are not limited to the specific values listed in the defined range. As used herein, "and / or" is inclusive, e.g., "A and / or B" means only A, or only B, or both A and B.

[0034] [ESSENTIAL COMPONENTS AND OPTIONAL COMPONENTS]

[0035] SiO2is the skeleton of the glass material, as a glass network former, has the effect of maintaining the chemical stability of the glass and improving the glass resistance to devitrification, if the content of SiO2is less than 17%, the above effect is not obvious, therefore the lower limit of the content of SiO2is 17%, preferably the lower limit is 21%, more preferably the lower limit is 22%. If the content of SiO2is higher than 32%, the melting property of the glass decreases, the transition temperature and the high temperature viscosity rise, which is not conducive to the improvement of the light transmittance of the glass, therefore the upper limit of the content of SiO2is 32%, preferably the upper limit is 30%, more preferably the upper limit is 28%.

[0036] B2O3is a component forming the glass network structure, is a necessary component of the glass of the present application, by containing 18% or more of B2O3, the melting property, the resistance to devitrification and the light transmittance of the glass can be improved; if the content of B2O3exceeds 32%, the chemical stability of the glass becomes poor, the volatilization of the glass increases, which is not conducive to the stable control of the optical constants, and the striation degree is prone to deterioration. Therefore, the content of B2O3is 18-32%, preferably 21-30%, more preferably 22-29%.

[0037] In some embodiments, the ratio between the content of B2O3and the content of SiO2, B2O3 / SiO2, is controlled in the range of 0.7-1.7, which can reduce the high temperature viscosity of the glass while preventing the decrease of the Young's modulus. Therefore, it is preferred that B2O3 / SiO2is 0.7-1.7, more preferably B2O3 / SiO2is 0.75-1.5. Further, controlling B2O3 / SiO2in the range of 0.8-1.3 can further optimize the transmittance and the thermal expansion coefficient of the glass. Therefore, it is further preferred that B2O3 / SiO2is 0.8-1.3, more further preferred that B2O3 / SiO2is 0.85-1.1.

[0038] La2O3is a necessary component of the glass of the present application, can increase the refractive index of the glass, improve the chemical stability and mechanical strength of the glass, and can reduce the relative partial dispersion of the glass, in the present application, by containing 7.5% or more of La2O3to obtain the above effects, preferably containing 11% or more of La2O3, more preferably containing 12% or more of La2O3. If the content of La2O3exceeds 23%, the anti-crystallization property and the thermal stability of the glass tend to deteriorate. Therefore, in the present application, the content of La2O3is 23% or less, preferably the content is 20% or less, more preferably 18% or less.

[0039] In some embodiments, the ratio of the content of La2O3 to the content of SiO2, La2O3 / SiO2, is controlled in the range of 0.3 to 1.2, so that the glass has excellent wear resistance while preventing the transformation temperature from rising. Therefore, it is preferable that La2O3 / SiO2 be 0.3 to 1.2, more preferable that La2O3 / SiO2 be 0.35 to 1.0. Further, controlling La2O3 / SiO2 in the range of 0.4 to 0.9 can further optimize the light transmittance of the glass. Therefore, it is further preferable that La2O3 / SiO2 be 0.4 to 0.9, and more further preferable that La2O3 / SiO2 be 0.45 to 0.8.

[0040] Gd2O3 can increase the refractive index and chemical stability of the glass, but if its content is higher than 8%, the glass has poor resistance to devitrification and wear resistance. Therefore, the content of Gd2O3 is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 1.5%. In some embodiments, it is further preferable that Gd2O3 is not contained.

[0041] Y2O3 can increase the refractive index of the glass, reduce the density and the upper limit of crystallization temperature, but if its content is higher than 8%, the glass has poor resistance to devitrification and weather resistance. Therefore, the content of Y2O3 in the present application is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 1.5%. In some embodiments, it is further preferable that Y2O3 is not contained.

[0042] Yb2O3 is also a component that imparts high refractive and low dispersion properties to the glass, and if its content exceeds 5%, the glass has poor resistance to crystallization. Therefore, the content of Yb2O3 is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 2%. In some embodiments, it is further preferable that Yb2O3 is not contained.

[0043] In some embodiments, the total content of La2O3, Gd2O3, Y2O3, and Yb2O3, Ln2O3, is controlled in the range of 7.5 to 28%, so that the desired refractive index is easily obtained while improving the chemical stability, and preventing the glass from having poor resistance to crystallization. Therefore, it is preferable that the content of Ln2O3 be 7.5 to 28%, more preferable that the content of Ln2O3 be 10 to 25%, and further preferable that the content of Ln2O3 be 11 to 20%.

[0044] ZrO2 can adjust the optical constant of the glass, improve the resistance to devitrification and chemical stability, but if its content exceeds 10%, the melting property of the glass decreases, the melting temperature rises, and it is easy to cause inclusions in the glass and decrease the transmittance, and it is difficult to maintain a low transformation temperature. Therefore, the content of ZrO2 is 0 to 10%, preferably 0.5 to 8%, and more preferably 1 to 7%.

[0045] In some embodiments, the ratio between the content of ZrO2 and the content of SiO2, ZrO2 / SiO2, is controlled in the range of 0.01 to 0.4, which can improve the hardness and chemical stability of the glass and prevent the anti-crystallization performance from deteriorating. Therefore, ZrO2 / SiO2 is preferably 0.01 to 0.4, more preferably 0.05 to 0.35, and further preferably 0.1 to 0.3.

[0046] Nb2O5 can increase the refractive index and dispersion of the glass, and can also improve the anti-crystallization and chemical stability of the glass. If the content of Nb2O5 exceeds 5%, the dispersion of the glass increases, the optical properties of the glass of the present application cannot be achieved, and the light transmittance of the glass decreases. Therefore, the content of Nb2O5 is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is further preferred that Nb2O5 is not contained.

[0047] WO3 can increase the refractive index and dispersion of the glass. If the content of WO3 is too high, the light transmittance of the glass decreases and the anti-crystallization performance deteriorates. Therefore, the content of WO3 is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is further preferred that WO3 is not contained.

[0048] ZnO can decrease the transition temperature of the glass, improve the chemical stability of the glass, and decrease the high-temperature viscosity of the glass. If the content of ZnO is too high, the anti-crystallization performance of the glass deteriorates and the thermal expansion coefficient increases. Therefore, the content of ZnO in the present application is 0 to 4.5%, preferably 0 to 3%, and more preferably 0 to 2%. In some embodiments, it is further preferred that ZnO is not contained.

[0049] Alkali metal oxide Rn2O (Rn2O is one or more of Li2O, Na2O, and K2O) can decrease the transition temperature of the glass, adjust the optical constants and high-temperature viscosity of the glass, and improve the melting property of the glass. However, when the content of Rn2O is high, the resistance to devitrification and chemical stability of the glass decrease. Therefore, the content of Rn2O in the present application is 0 to 6.5%, preferably 0 to 5%, and more preferably 0 to 2%.

[0050] Li2O can decrease the transition temperature of the glass. However, a high content of Li2O is not conducive to the acid resistance and thermal expansion coefficient of the glass, and corrodes the melting container (such as a platinum crucible). Therefore, the content of Li2O is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 2%.

[0051] Na2O can improve the melting property of the glass and decrease the transition temperature of the glass. However, when the content of Na2O is too high, the chemical stability and weather resistance of the glass decrease. Therefore, the content of Na2O is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 2%. In some embodiments, it is further preferred that Na2O is not contained.

[0052] K2O has the effect of improving the thermal stability and melting property of the glass, but when the content of K2O exceeds 5%, the devitrification resistance of the glass decreases. Therefore, the content of K2O is 0-5%, preferably 0-3%, more preferably 0-2%. In some embodiments, it is further preferred that K2O is not contained.

[0053] MgO can reduce the melting temperature and relative partial dispersion of the glass, but when the content of MgO is too high, the anti-crystallization performance and stability of the glass decrease. Therefore, the content of MgO is 0-5%, preferably 0-3%, more preferably 0-2%. In some embodiments, it is further preferred that MgO is not contained.

[0054] CaO helps to improve the density and processing performance of the glass, but when the content of CaO is too high, it is difficult to achieve the design requirements for the optical constants of the glass, and the anti-crystallization performance deteriorates. Therefore, the content of CaO is 0-4%, preferably 0-3%, more preferably 0-2%. In some embodiments, it is further preferred that CaO is not contained.

[0055] In some embodiments, the ratio between the total content of ZnO, CaO, and Rn2O (ZnO+CaO+Rn2O) and the content of La2O3 (ZnO+CaO+Rn2O) / La2O3) is controlled to be below 1.0, which can improve the chemical stability and light transmittance of the glass and prevent the density and abrasion degree from deteriorating. Therefore, it is preferred that (ZnO+CaO+Rn2O) / La2O3 is below 1.0, more preferably (ZnO+CaO+Rn2O) / La2O3 is below 0.8, further preferably (ZnO+CaO+Rn2O) / La2O3 is below 0.5, more further preferably (ZnO+CaO+Rn2O) / La2O3 is below 0.3.

[0056] SrO can improve the devitrification resistance of the glass and improve the melting performance of the glass, but if its content is too high, it is difficult to achieve the design requirements for the refractive index of the glass, and the cost of the glass will also rapidly increase. Therefore, the content of SrO is 2-15%, preferably 3-13%, more preferably 5.5-11%.

[0057] In some embodiments, the ratio between the content of SrO and the content of La2O3 (SrO / La2O3) is controlled to be within the range of 0.1-1.5, which can improve the chemical stability and Young's modulus of the glass and prevent the thermal expansion coefficient of the glass from increasing. Therefore, it is preferred that SrO / La2O3 is 0.1-1.5, more preferably SrO / La2O3 is 0.2-1.2, further preferably SrO / La2O3 is 0.3-1.0, more further preferably SrO / La2O3 is 0.35-0.8.

[0058] In some embodiments, by controlling the ratio between the total content of Y2O3, Gd2O3, ZnO, CaO, Rn2O and the content of SrO (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO to be below 1.0, the high temperature viscosity and transition temperature of the glass can be reduced while preventing the deterioration of hardness. Therefore, it is preferred that (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO be below 1.0, more preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO be below 0.8, further preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO be below 0.5, more further preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO be below 0.3.

[0059] BaO has the effects of adjusting the refractive index of the glass, improving the transmittance and devitrification resistance of the glass, and reducing the refractive index temperature coefficient and thermal expansion coefficient of the glass in the present application. If the content of BaO is too high, the chemical stability of the glass will decrease. Therefore, the content of BaO is 12-27.5%, preferably 15-25%, more preferably 16-23%.

[0060] In some embodiments, by controlling the ratio between the total content of La2O3 and SrO (La2O3+SrO) and the content of BaO (La2O3+SrO) / BaO to be in the range of 0.5-2.5, the thermal expansion coefficient and transition temperature of the glass can be reduced while preventing the decrease of the Young's modulus of the glass. Therefore, it is preferred that (La2O3+SrO) / BaO be in the range of 0.5-2.5, more preferably (La2O3+SrO) / BaO be in the range of 0.7-2.0, further preferably (La2O3+SrO) / BaO be in the range of 0.8-1.8, more further preferably (La2O3+SrO) / BaO be in the range of 0.9-1.5.

[0061] TiO2 has the effect of increasing the refractive index of the glass and can participate in the formation of the glass network. The appropriate amount of TiO2 can make the glass more stable, but too much TiO2 will result in the decrease of the light transmittance of the glass and obvious glass coloring. Therefore, the content of TiO2 in the present application is 0-5%, preferably 0-3%, more preferably 0-2%. In some embodiments, it is further preferred that TiO2 not be contained.

[0062] Al2O3 can improve the stability and devitrification resistance of the glass and increase the strength of the glass. When the content of Al2O3 exceeds 10%, the chemical stability and melting property of the glass will decrease. Therefore, the content of Al2O3 in the present application is 0-10%, preferably 1-8%, more preferably 2-7%.

[0063] In some embodiments, the ratio of the content of Al2O3 to the content of ZrO2, Al2O3 / ZrO2, is controlled in the range of 0.2 to 8.0, which can reduce the high-temperature viscosity of the glass while preventing the anti-crystallization performance of the glass from deteriorating. Therefore, it is preferred that Al2O3 / ZrO2 be in the range of 0.2 to 8.0, more preferably, Al2O3 / ZrO2 be in the range of 0.5 to 6.0. Further, Al2O3 / ZrO2 is in the range of 0.8 to 4.0, which can further optimize the hardness and abrasion of the glass. Therefore, it is further preferred that Al2O3 / ZrO2 be in the range of 0.8 to 4.0, and more further preferred that Al2O3 / ZrO2 be in the range of 1.0 to 2.0.

[0064] In some embodiments, the ratio of the content of Al2O3 to the content of B2O3, Al2O3 / B2O3, is controlled in the range of 0.01 to 0.45, which can reduce the thermal expansion coefficient of the glass while preventing the transition temperature of the glass from increasing and improving the light transmittance of the glass. Therefore, it is preferred that Al2O3 / B2O3 be in the range of 0.01 to 0.45, more preferably, Al2O3 / B2O3 be in the range of 0.05 to 0.4, and further preferably, Al2O3 / B2O3 be in the range of 0.1 to 0.3.

[0065] In some embodiments, the ratio of the total content of BaO and SrO, BaO+SrO, to the total content of ZrO2 and Al2O3, ZrO2+Al2O3, (BaO+SrO) / (ZrO2+Al2O3) is controlled in the range of 1.0 to 15.0, which can reduce the density of the glass while optimizing the abrasion of the glass. Therefore, it is preferred that (BaO+SrO) / (ZrO2+Al2O3) be in the range of 1.0 to 15.0, more preferably, (BaO+SrO) / (ZrO2+Al2O3) be in the range of 1.5 to 10.0. Further, (BaO+SrO) / (ZrO2+Al2O3) is in the range of 2.0 to 8.0, which can further optimize the high-temperature viscosity of the glass. Therefore, it is further preferred that (BaO+SrO) / (ZrO2+Al2O3) be in the range of 2.0 to 8.0, and more further preferred that (BaO+SrO) / (ZrO2+Al2O3) be in the range of 2.5 to 5.0.

[0066] Ta2O5 can increase the refractive index of the glass and improve the resistance of the glass to devitrification, but if its content is too high, the thermal stability of the glass decreases and the density increases; on the other hand, compared with other components, Ta2O5 is very expensive, and from the practical and cost perspectives, the use amount of Ta2O5 should be reduced as much as possible. Therefore, the content of Ta2O5 in the present application is limited to 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is further preferred that Ta2O5 be not contained.

[0067] P2O5 can improve the resistance to devitrification of the glass, but if its content is too high, the chemical stability of the glass becomes poor. Therefore, the content of P2O5 is 0-4%, preferably 0-2%, and more preferably 0-1%. In some embodiments, it is further preferred that P2O5 is not contained.

[0068] In the present application, by containing 0-1% of one or more components of Sb2O3, SnO2, SnO, and CeO2 as fining agents, the fining effect of the glass can be improved, and the bubble degree of the glass can be improved. Preferably, the content of the fining agent is 0-0.5%, and more preferably, the content of the fining agent is 0-0.2%.

[0069] F can be used to adjust the refractive index of the glass and reduce the refractive index temperature coefficient. However, during its production process, it causes environmental load problems due to its volatilization, and in the forming operation temperature range, it forms inhomogeneous parts due to its volatilization from the surface of the glass, which reduces the glass quality and the consistency of the optical constants. Therefore, the content of F is 0-5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is further preferred that F is not contained.

[0070] <Components not to be contained>

[0071] In the glass of the present application, even if transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are contained in small amounts, alone or in combination, the glass will be colored, and absorption will occur at specific wavelengths in the visible light region, thereby reducing the effect of the present application of improving the visible light transmittance. Therefore, for glass materials that require transmittance at wavelengths in the visible light region, it is preferred that they are not actually contained.

[0072] The oxides of Th, Cd, Tl, Os, Be, and Se have a tendency to be controlled in use as harmful chemical substances in recent years, and measures for environmental protection are necessary not only in the manufacturing process of the glass, but also in the processing process and disposal after productization. Therefore, in the case where the influence on the environment is taken into consideration, it is preferred that they are not actually contained except for inevitable mixing. Thus, the glass material becomes one that does not actually contain substances that pollute the environment. Therefore, even without taking special measures for environmental countermeasures, the glass material of the present application can be manufactured, processed, and disposed of.

[0073] In order to achieve environmental friendliness, the glass material of the present application preferably does not contain As2O3 and PbO. Although As2O3 has the effect of eliminating bubbles and better preventing the glass from being colored, the addition of As2O3 increases the platinum attack of the glass on the furnace, particularly on the platinum furnace, resulting in more platinum ions entering the glass, which adversely affects the service life of the platinum furnace.

[0074] The "not containing" "0%" described herein means that the compound, molecule or element is not intentionally added as a raw material to the glass material of the present application; but as a raw material and / or equipment for producing the glass material, there may be some impurities or components that are not intentionally added, which may be contained in a small amount or trace amount in the final glass material, and such a case is also within the protection scope of the present application.

[0075] Next, the performance of the glass material of the present application is described.

[0076] <Refractive index and Abbe number>

[0077] The refractive index (n d ) and Abbe number (ν d ) of the glass material are tested according to the method specified in GB / T 7962.1-2010.

[0078] In some embodiments, the upper limit of the refractive index (n d ) of the glass material of the present application is 1.66, preferably 1.65, and more preferably 1.64.

[0079] In some embodiments, the lower limit of the refractive index (n d ) of the glass material of the present application is 1.59, preferably 1.60, and more preferably 1.61.

[0080] In some embodiments, the upper limit of the Abbe number (ν d ) of the glass material of the present application is 61, preferably 60, and more preferably 59.

[0081] In some embodiments, the lower limit of the Abbe number (ν d ) of the glass material of the present application is 55, preferably 56, and more preferably 57.

[0082] <Transition temperature>

[0083] The transition temperature (T g ) of the glass material is tested according to the method specified in GB / T 7962.16-2010.

[0084] In some embodiments, the transition temperature (T g ) of the glass material of the present application is 650℃ or lower, preferably 600-650℃, more preferably 605-645℃, and further preferably 610-640℃.

[0085] <Resistance to water action>

[0086] The resistance to water action (D W ) of the glass material (powder method) is tested according to the method specified in GB / T 17129.​

[0087] In some embodiments, the water resistance stability (D) of the glass material of the present invention is... W It is classified into three or more categories, preferably two or more categories, and more preferably one category.

[0088] <Density>

[0089] The density (ρ) of the glass material was tested according to the method specified in GB / T7962.20—2010.

[0090] In some embodiments, the density (ρ) of the glass material of the present invention is 3.60 g / cm³. 3 The preferred value is 3.50 g / cm³. 3 The preferred value is 3.40 g / cm³. 3 the following.

[0091] Knoop Hardness

[0092] Knoop hardness (H) of glass materials K Test according to the method specified in GB / T7962.18—2010.

[0093] In some embodiments, the Knoop hardness (H) of the glass material of the present invention is... K ) is 500×10 7 Pa or higher, preferably 515 × 10 Pa 7 Pa or higher, more preferably 530 × 10 Pa 7 Pa or above.

[0094] Young's Modulus

[0095] The Young's modulus (E) of glass materials is obtained by ultrasonic testing of its longitudinal wave velocity and transverse wave velocity, and then calculated using the following formula: G = V S 2 ρ

[0096] In the formula: E is Young's modulus, Pa;

[0097] G is the shear modulus, Pa;

[0098] V T The transverse wave velocity is in m / s;

[0099] V S The longitudinal wave velocity is given in m / s.

[0100] ρ is the density of glass, in g / cm³ 3 .

[0101] In some embodiments, the Young's modulus (E) of the glass material of the present invention is 7000 × 10⁻⁶. 7Pa or more, preferably 7300 x 10 7 Pa or more, more preferably 7600 x 10 7 Pa or more.

[0102] <abrasion degree>

[0103] The abrasion degree (F A ) of the glass material refers to the ratio of the abrasion amount of the sample to the abrasion amount (volume) of the standard sample (H-K9 glass) under the same conditions, multiplied by 100, and is expressed by the following formula:

[0104] In the formula, V refers to the volume abrasion amount of the sample to be measured;

[0105] V0 refers to the volume abrasion amount of the standard sample;

[0106] W refers to the mass abrasion amount of the sample to be measured;

[0107] W0 refers to the mass abrasion amount of the standard sample;

[0108] p refers to the density of the sample to be measured;

[0109] p0 refers to the density of the standard sample.

[0110] In some embodiments, the abrasion degree (F A ) of the glass material of the present application is 200 or less, preferably 175 or less, and more preferably 150 or less.

[0111] <coefficient of thermal expansion>

[0112] The coefficient of thermal expansion (a 20 / 300℃ ) of the glass material is tested according to the method specified in GB / T 7962.16-2010 at 20-300℃.

[0113] In some embodiments, the coefficient of thermal expansion (a 20 / 300℃ ) of the glass material of the present application is 90 x 10 -7 / K or less, preferably 50 x 10 -7 / K-85 x 10 -7 / K, more preferably 55 x 10 -7 / K-80 x 10 -7 / K, and further preferably 60 x 10 -7 / K-72 x 10 -7 / K.

[0114] <anti-crystallization property>

[0115] The test method for the anti-crystallization property of the glass material is as follows: the sample glass is cut into a size of 20 x 20 x 10 mm, and is placed in a temperature-controlled oven at T gThe glass sample is taken out from the muffle furnace and cooled. The surface and interior of the glass sample are observed to determine whether devitrification or crystal particles are present. If the glass sample does not have devitrification or crystal particles, the glass has excellent resistance to devitrification.

[0116] According to the foregoing test method, "A" indicates that the surface of the glass does not have devitrification or crystal particles and the interior of the glass does not have crystal particles, "B" indicates that the interior of the glass does not have crystal particles but the surface layer of the glass has devitrification or crystal particles, "C" indicates that the interior of the glass has 1-10 crystal particles, "D" indicates that the interior of the glass has 10-20 crystal particles, and "X" indicates that the interior of the glass has more than 20 intensive crystal particles.

[0117] In some embodiments, the glass material of the present application has a resistance to devitrification of grade B or above, preferably grade A.

[0118] <High temperature viscosity>

[0119] The high temperature viscosity of the glass material is tested by using a THETA Rheotronic II high temperature viscometer by a rotation method, and the numerical value is dPaS (poise). The smaller the numerical value, the smaller the viscosity.

[0120] In some embodiments, the high temperature viscosity of the glass material at 1200°C is 60 dPaS or less, preferably the high temperature viscosity at 1200°C is 40 dPaS or less, and more preferably the high temperature viscosity at 1200°C is 30 dPaS or less.

[0121] <400-800 nm average light transmittance>

[0122] The 400-800 nm average light transmittance (τ 400～800nm ) of the glass material is tested according to the method specified in GB / T 7962.12-2010. The higher the 400-800 nm average light transmittance, the smaller the average light transmission loss of the glass material.

[0123] In some embodiments, the 400-800 nm average light transmittance (τ 400～800nm ) of the glass material with a thickness of 12 mm or less is 99.0% or more, preferably 99.5% or more, and more preferably 99.7% or more.

[0124] The thickness of the above-mentioned glass material is preferably 1-12 mm, more preferably 2-12 mm, further preferably 5-10 mm, and more further preferably 2 mm or 5 mm or 8 mm or 10 mm.

[0125] <400 nm light transmittance>

[0126] The 400 nm light transmittance (τ 400nm) is tested according to the method prescribed in GB / T 7962.12-2010. The higher the 400 nm light transmittance of the glass material, the lower the light absorption of the glass material in the blue band, and the closer the lighting effect to white light.

[0127] In some embodiments, the 400 nm light transmittance (τ 400nm ) of the glass material is 99.0% or more, preferably 99.5% or more, and more preferably 99.7% or more.

[0128] The thickness of the glass material is preferably 1 to 12 mm, more preferably 2 to 12 mm, further preferably 5 to 10 mm, and more further preferably 2 mm or 5 mm or 8 mm or 10 mm.

[0129] [Manufacturing method]

[0130] The manufacturing method of the glass material of the present application is as follows: The glass of the present application is produced using conventional raw materials and processes, including but not limited to using oxides, hydroxides, fluorides, various salts (carbonates, nitrates, sulfates, phosphates, metaphosphates), boric acid, etc. as raw materials, and after batching according to conventional methods, the prepared batch is put into a smelting furnace (such as a platinum, gold or platinum alloy crucible) at 1000 to 1400°C for smelting, and after refining and homogenization, a homogeneous molten glass without bubbles and undissolved substances is obtained, which is cast in a mold and annealed to form the glass material. Those skilled in the art can appropriately select raw materials, process methods and process parameters according to actual needs.

[0131] [Glass preform and glass element]

[0132] A glass preform can be made from the manufactured glass material using, for example, a grinding processing means, or a re-press forming, precision press forming, etc. That is, a glass preform can be made by mechanical processing such as grinding and polishing of the glass material, or by re-press forming of a preform blank for press forming made of the glass material, followed by grinding processing, or by precision press forming of a preform blank made by grinding processing.

[0133] It should be noted that the means for preparing a glass preform is not limited to the above means. As described above, the glass material of the present application is useful for various glass elements and optical designs, among which it is particularly preferable to form a preform blank from the glass material of the present application, and to use the preform blank for re-press forming, precision press forming, etc. to make glass elements such as lenses, prisms, etc.

[0134] Both the glass preform and the glass element of the present invention are formed from the glass material described above. The glass preform of the present invention possesses the excellent properties of the glass material; the glass element of the present invention possesses the excellent properties of the glass material, and can provide various lenses, prisms, and other glass elements with high optical value.

[0135] Examples of lenses include concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, plano-concave lenses, and so on, where the lens surface is spherical or aspherical.

[0136] The glass material of this invention can be used to draw glass components such as optical fibers.

[0137] [Optical Instruments]

[0138] The glass elements formed from the glass material of this invention can be used to manufacture optical instruments such as photographic equipment, video equipment, endoscopes, display devices, and monitoring equipment.

[0139] Example

[0140] <Examples of Glass Materials>

[0141] To further illustrate and explain the technical solution of the present invention, the following non-limiting embodiments are provided.

[0142] In this embodiment, glass materials with the compositions shown in Tables 1 to 3 were obtained using the glass material manufacturing method described above. Furthermore, the properties of each glass were measured using the testing method described in this invention, and the measurement results are shown in Tables 1 to 3. In the following embodiments, the average light transmittance (τ) of the glass material from 400 to 800 nm is... 400～800nm ) and 400nm light transmittance (τ) 400nm The test results were obtained using 10mm thick glass material.

[0143] Table 1.

[0144] Table 2.

[0145] Table 3.

[0146] <Example of Glass Prefabricated Components>

[0147] The glass obtained in Examples 1 to 24 is used to manufacture preforms of various lenses and prisms, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, by means of grinding, hot pressing, precision stamping, or other molding.

[0148] <Example of glass element>

[0149] The preforms obtained in the above glass preform example are annealed to reduce internal deformation of the glass and fine-tune the optical properties such as refractive index to the desired values.

[0150] Next, each preform is ground and polished to produce various lenses such as concave meniscus lenses, convex meniscus lenses, lenticular lenses, double concave lenses, plano-convex lenses, and plano-concave lenses, and prisms. The surface of the obtained glass element can also be coated with an antireflection film.

[0151] <Example of optical instrument>

[0152] The glass element obtained in the above glass element example is used in optical design to form an optical component or optical assembly using one or more glass elements, which can be used, for example, in imaging devices, sensors, microscopes, medical technology, digital projection, communication, optical communication technology / information transmission, optics / illumination in the automotive field, photolithography technology, excimer lasers, wafers, computer chips, and integrated circuits and electronic devices including such circuits and chips, or in the field of vehicle-mounted imaging devices and apparatuses.

Claims

1. Glass material, characterized in that, comprising, in percent by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; SrO: 2-15%.

2. The glass material of claim 1, wherein, comprising, in percent by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; SrO: 2-15%; Al2O3: 0-10%; ZrO2: 0-10%; Gd2O3: 0-8%; Y2O3: 0-8%; Yb2O3: 0-5%; Nb2O5: 0-5%; WO3: 0-5%; ZnO: 0-4.5%; Rn2O: 0-6.5%; MgO: 0-5%; CaO: 0-4%; TiO2: 0-5%; Ta2O5: 0-5%; P2O5: 0-4%; clarifier: 0-1%, said Rn2O being one or more of Li2O, Na2O, K2O, and the clarifier being one or more of Sb2O3, SnO2, SnO, CeO2.

3. Glass material, characterized in that comprising, in percent by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; SrO: 2-15%; Al2O3: 0-10%; ZrO2: 0-10%; Gd2O3: 0-8%; Y2O3: 0-8%; Yb2O3: 0-5%; Nb2O5: 0-5%; WO3: 0-5%; ZnO: 0-4.5%; Rn2O: 0-6.5%; MgO: 0-5%; CaO: 0-4%; TiO2: 0-5%; Ta2O5: 0-5%; P2O5: 0-4%; clarifier: 0-1%, said Rn2O being one or more of Li2O, Na2O, K2O, and the clarifier being one or more of Sb2O3, SnO2, SnO, CeO2. comprising, in percent by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; SrO: 2-15%; Al2O3: 0-10%; ZrO2: 0-10%; Gd2O3: 0-8%; Y2O3: 0-8%; Yb2O3: 0-5%; Nb2O5: 0-5%; WO3: 0-5%; ZnO: 0-4.5%; Rn2O: 0-6.5%; MgO: 0-5%; CaO: 0-4%; TiO2: 0-5%; Ta2O5: 0-5%; P2O5: 0-4%; clarifier: 0-1%, said Rn2O being one or more of Li2O, Na2O, K2O, and the clarifier being one or more of Sb2O3, SnO2, SnO, CeO2. comprising, in percent by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; SrO: 2-15%; Al2O3: 0-10%; ZrO2: 0-10%; Gd2O3: 0-8%; Y2O3: 0-8%; Yb2O3: 0-5%; Nb2O5: 0-5%; WO3: 0-5%; ZnO: 0-4.5%; Rn2O: 0-6.5%; MgO: 0-5%; CaO: 0-4%; TiO2: 0-5%; Ta2O5: 0-5%; P2O5: 0-4%; clarifier: 0-1%, said Rn2O being one or more of Li2O, Na2O, K2O, and the clarifier being one or more of Sb2O3, SnO2, SnO, CeO2. comprising, in percent by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; SrO: 2-15%; Al2O3: 0-10%; ZrO2: 0-10%; Gd2O3: 0-8%; Y2O3: 0-8%; Yb2O3: 0-5%; Nb2O5: 0-5%; WO3: 0-5%; ZnO: 0-4.5%; Rn2O: 0-6.5%; MgO: 0-5%; CaO: 0-4%; TiO2: 0-5%; Ta2O5: 0-5%; P2O5: 0-4%; clarifier: 0-1%, said Rn2O being one or more of Li2O, Na2O, K2O, and the clarifier being one or more of Sb2O3, SnO2, SnO, CeO2. comprising, in percent by weight: SiO2: 17-32%; B2O3: 18-32%; La2O3: 7.5-23%; BaO: 12-27.5%; SrO: 2-15%; Al2O3: 0-10%; ZrO2: 0-10%; Gd2O3: 0-8%; Y2O3: 0-8%; Yb2O3: 0-5%; Nb2O5: 0-5%; WO3: 0-5%; ZnO: 0-4.5%; Rn2O: 0-6.5%; MgO: 0-5%; CaO: 0-4%; TiO2: 0-5%; Ta2O5: 0-5%; P2O5: 0-4%; clarifier: 0-1%, said Rn2O being one or more of Li2O, Na2O, K2O, and the clarifier being one or more of Sb2O3, SnO2, SnO, CeO2. F：0～5％； ​ 4. The glass material according to any one of claims 1 to 3, characterized in that ​ ​ ​ ​ 4) SrO / La2O3 is 0.1 to 1.5, preferably SrO / La2O3 is 0.2 to 1.2, more preferably SrO / La2O3 is 0.3 to 1.0, further preferably SrO / La2O3 is 0.35 to 0.8; 5) La2O3 / SiO2 is 0.3 to 1.2, preferably La2O3 / SiO2 is 0.35 to 1.0, more preferably La2O3 / SiO2 is 0.4 to 0.9, further preferably La2O3 / SiO2 is 0.45 to 0.8; 6) (BaO + SrO) / (ZrO2 + Al2O3) is 1.0 to 15.0, preferably (BaO + SrO) / (ZrO2 + Al2O3) is 1.5 to 10.0, more preferably (BaO + SrO) / (ZrO2 + Al2O3) is 2.0 to 8.0, further preferably (BaO + SrO) / (ZrO2 + Al2O3) is 2.5 to 5.0; 7) Al2O3 / B2O3 is 0.01 to 0.45, preferably Al2O3 / B2O3 is 0.05 to 0.4, more preferably Al2O3 / B2O3 is 0.1 to 0.3; 8) ZrO2 / SiO2 is 0.01 to 0.4, preferably ZrO2 / SiO2 is 0.05 to 0.35, more preferably ZrO2 / SiO2 is 0.1 to 0.3; 9) Al2O3 / ZrO2 is 0.2 to 8.0, preferably Al2O3 / ZrO2 is 0.5 to 6.0, more preferably Al2O3 / ZrO2 is 0.8 to 4.0, further preferably Al2O3 / ZrO2 is 1.0 to 2.0; 10) (Y2O3 + Gd2O3 + ZnO + CaO + Rn2O) / SrO is 1.0 or less, preferably (Y2O3 + Gd2O3 + ZnO + CaO + Rn2O) / SrO is 0.8 or less, more preferably (Y2O3 + Gd2O3 + ZnO + CaO + Rn2O) / SrO is 0.5 or less, further preferably (Y2O3 + Gd2O3 + ZnO + CaO + Rn2O) / SrO is 0.3 or less; 11) (ZnO + CaO + Rn2O) / La2O3 is 1.0 or less, preferably (ZnO + CaO + Rn2O) / La2O3 is 0.8 or less, more preferably (ZnO + CaO + Rn2O) / La2O3 is 0.5 or less, further preferably (ZnO + CaO + Rn2O) / La2O3 is 0.3 or less, the Rn2O is one or more of Li2O, Na2O, K2O, and Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, Yb2O3.

5. The glass material according to any one of claims 1 to 3, characterized in that , its components being expressed in percentage by weight, wherein: SiO2: 21-30%, preferably SiO2: 22-28%; and / or B2O3: 21-30%, preferably B2O3: 22-29%; and / or La2O3: 11-20%, preferably La2O3: 12-18%; and / or BaO: 15-25%, preferably BaO: 16-23%; and / or SrO: 3-13%, preferably SrO: 5.5-11%; and / or Al2O3: 1-8%, preferably Al2O3: 2-7%; and / or ZrO2: 0.5-8%, preferably ZrO2: 1-7%; and / or Gd2O3: 0-5%, preferably Gd2O3: 0-1.5%, more preferably free of Gd2O3; and / or Y2O3: 0-5%, preferably Y2O3: 0-1.5%, more preferably free of Y2O3; and / or Yb2O3: 0-3%, preferably Yb2O3: 0-2%, more preferably free of Yb2O3; and / or Nb2O5: 0-3%, preferably Nb2O5: 0-1%, more preferably free of Nb2O5; and / or WO3: 0-3%, preferably WO3: 0-1%, more preferably free of WO3; and / or ZnO: 0-3%, preferably ZnO: 0-2%, more preferably free of ZnO; and / or Rn2O: 0-5%, preferably Rn2O: 0-2%; and / or MgO: 0-3%, preferably MgO: 0-2%, more preferably free of MgO; and / or CaO: 0-3%, preferably CaO: 0-2%, more preferably free of CaO; and / or TiO2: 0-3%, preferably TiO2: 0-2%, more preferably free of TiO2; and / or Ta2O5: 0-3%, preferably Ta2O5: 0-1%, more preferably free of Ta2O5; and / or P2O5: 0-2%, preferably P2O5: 0-1%, more preferably free of P2O5; and / or F: 0-3%, preferably F: 0-2%, more preferably free of F; and / or fining agent: 0-0.5%, preferably fining agent: 0-0.2%, said Rn2O being one or more of Li2O, Na2O, K2O, and the fining agent being one or more of Sb2O3, SnO2, SnO, CeO2.

6. The glass material according to any one of claims 1 to 3, characterized in that , its components being expressed in percentage by weight, wherein: Li2O: 0-5%, preferably Li2O: 0-3%, more preferably Li2O: 0-2%; and / or Na2O: 0-5%, preferably Na2O: 0-3%, more preferably Na2O: 0-2%, further preferably free of Na2O; and / or K2O: 0-5%, preferably K2O: 0-3%, more preferably K2O: 0-2%, further preferably free of K2O.

7. The glass material according to any one of claims 1 to 3, characterized by 400 to 800 nm average light transmittance τ of a glass material having a thickness of 1 to 12 mm 400～800nm is 99.0% or more, preferably 99.5% or more, more preferably 99.7% or more; and / or the 400 nm light transmittance τ of a glass material having a thickness of 1 to 12 mm 400nm is 99.0% or more, preferably 99.5% or more, more preferably 99.7% or more; and / or the refractive index n d is 1.59 to 1.66, preferably 1.60 to 1.65, more preferably 1.61 to 1.64; and / or the Abbe number v d is 55 to 61, preferably 56 to 60, more preferably 57 to 59; and / or the transition temperature T g is 650°C or less, preferably 600 to 650°C, more preferably 605 to 645°C, further preferably 610 to 640°C; and / or the water resistance stability D W is Class 3 or more, preferably Class 2 or more, more preferably Class 1; and / or the density p is 3.60 g / cm 3 or more, preferably 3.50 g / cm 3 or more, more preferably 3.40 g / cm 3 or more; and / or the Knoop hardness H K is 500 x 10 7 Pa or more, preferably 515 x 10 7 Pa or more, more preferably 530 x 10 7 Pa or more; and / or the Young's modulus E is 7000 x 10 7 Pa or more, preferably 7300 x 10 7 Pa or more, more preferably 7600 x 10 7 Pa or more; and / or the abrasion degree F A is 200 or less, preferably 175 or less, more preferably 150 or less; and / or the thermal expansion coefficient a 20 / 300℃ is 90 x 10 -7 / K or less, preferably 50 x 10 -7 / K to 85 x 10 -7 / K, more preferably 55 x 10 -7 / K to 80 x 10 -7 / K, further preferably 60 x 10 -7 / K to 72 x 10 -7 / K; and / or the high temperature viscosity at 1200°C is 60 dPaS or less, preferably 40 dPaS or less, more preferably 30 dPaS or less; and / or the anti-crystallization property is Class B or more, preferably Class A.

8. Glass preform, characterized in that , made of a glass material according to any one of claims 1-7.

9. Glass element, characterized in that , made of a glass material according to any one of claims 1-7 or of a glass preform according to claim 8.

10. Optical instrument, characterized in that , containing a glass material according to any one of claims 1-7, or containing a glass element according to claim 9.

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