TWI756114B - Optical glass - Google Patents

Abstract

The invention provides an optical glass, the components of which are expressed in mole percentage, and contain: SiO ₂ : 60-80%; B ₂ O ₃ : 3-15%; TiO ₂ : 0.5-10%; ZnO: 0.5-13%; Al ₂ O ₃ : greater than 0 but less than or equal to 10%; Na ₂ O: 2-15%; K ₂ O: 1-10%, where (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO ) is 0.2 to 3.0, and (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 0.8 to 15.0. Through reasonable component design, the optical glass obtained by the present invention has lower thermal expansion coefficient and excellent chemical stability.

Description

Optical glass

The invention relates to an optical glass, in particular to an optical glass with a refractive index of 1.48-1.60 and an Abbe number of 50-58.

Optical glass with a refractive index of 1.48 to 1.60 and an Abbe number of 50 to 58 belongs to the coronal optical glass, which is widely used in various optical systems, such as a certain crown with a refractive index of 1.517 and an Abbe number of 64.2 Optical glass, the annual output in China alone can reach more than 6,000 tons.

In recent years, with the development of automotive headlight lenses, landscape lighting, and arts and crafts, different from general precision imaging applications, the above-mentioned fields require optical glass materials to be exposed to the outdoors for a long time for ten or even decades without obvious deterioration, which requires optical glass materials. Glass has excellent water resistance, acid resistance, alkali resistance and weather resistance. On the other hand, optical glass used in automotive and other fields also needs to withstand huge outdoor temperature differences, as well as the ability to withstand huge temperature differences during use. For example, automotive headlight lenses need to withstand the impact of cold water or even ice water at 70-80 °C. . At present, the commonly used crown glass is basically developed for precision imaging equipment, and the glass has a large thermal expansion coefficient. In the design process, the durability of optical components for long-term use in harsh outdoor conditions and the ability to withstand huge temperature differences are not considered. When making a lens, the light transmittance τ _{360 nm} needs to be more than 75%. While meeting the needs of light transmission, the temperature increase of the lens caused by light absorption, especially ultraviolet light absorption, is suppressed, and the risk of thermal shock cracking is reduced.

The technical problem to be solved by the present invention is to provide an optical glass with lower thermal expansion coefficient and excellent chemical stability.

The technical scheme adopted by the present invention to solve the technical problem is:

(1) Optical glass, whose components are expressed in mole percent, containing: SiO ₂ : 60-80%; B ₂ O ₃ : 3-15%; TiO ₂ : 0.5-10%; ZnO: 0.5-13%; Al ₂ O ₃ : greater than 0 but less than or equal to 10%; Na ₂ O: 2 to 15%; K ₂ O: 1 to 10%, wherein (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.2 to 3.0, and (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 0.8 to 15.0.

(2) The optical glass according to (1), the composition of which is expressed in mole percent, further comprising: MgO+CaO+SrO+BaO: 0-10%; and/or Li ₂ O: 0-5%; and and/or P ₂ O ₅ : 0-5%; and/or ZrO ₂ : 0-5%; and/or La ₂ O ₃ : 0-5%; and/or Y ₂ O ₃ : 0-5%; and /or Gd ₂ O ₃ : 0-5%; and/or Nb ₂ O ₅ : 0-5%; and/or WO ₃ : 0-5%; and/or clarifying agent: 0-1%.

(3) Optical glass, containing SiO ₂ , B ₂ O ₃ , ZnO, Al ₂ O ₃ , Na ₂ O and K ₂ O, and its components are expressed in mole percent, (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.2-3.0, (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 0.8-15.0, the refractive index of the optical glass is 1.48-1.60, and the Abbe number is 50-58 , the thermal expansion coefficient is below 90×10 ^-7 /K.

(4) The optical glass according to (3), whose components are expressed in mole percentages, and contain: SiO ₂ : 60-80%; B ₂ O ₃ : 3-15%; TiO ₂ : 0.5-10%; ZnO : 0.5-13%; Al ₂ O ₃ : greater than 0 but less than or equal to 10%; Na ₂ O: 2-15%; K ₂ O: 1-10%; MgO+CaO+SrO+BaO: 0-10% ; Li ₂ O : 0-5%; P ₂ O ₅ : 0-5%; ZrO ₂ : 0-5%; La ₂ O ₃ : 0-5%; Y ₂ O ₃ : 0-5%; Gd ₂ O ₃ : 0-5%; Nb ₂ O ₅ : 0-5%; WO ₃ : 0-5%; Clarifier: 0-1%.

(5) The optical glass according to any one of (1) to (4), whose components are expressed in mole percent, wherein: B ₂ O ₃ /SiO ₂ is 0.04 to 0.23; and/or (TiO ₂ +ZnO) /Al ₂ O ₃ is 0.2-10.0; and/or (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) is 2.5-15.0; and/or ZnO/B ₂ O ₃ is 0.1-3.0; and/or (Na ₂ O+K ₂ O)/Al ₂ O ₃ is 1.0 to 12.0.

(6) The optical glass according to any one of (1) to (4), the composition of which is expressed in mole percent, wherein: (MgO+CaO+SrO+BaO)/ZnO is 1.0 or less; and/or (MgO+ CaO+SrO+BaO)/Al ₂ O ₃ is 1.5 or less; and/or (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) is 1.0 or less.

(7) The optical glass according to any one of (1) to (4), the components of which are expressed in mole percent, and contain: SiO ₂ : 62-78%; and/or B ₂ O ₃ : 4-12%; and/or TiO ₂ : 1-8%; and/or ZnO: 1-10%; and/or Al ₂ O ₃ : 0.5-8%; and/or Na ₂ O: 3-12%; and/or K ₂ O: 2-8%; and/or MgO+CaO+SrO+BaO: 0-5%; and/or Li ₂ O: 0-3%; and/or P ₂ O ₅ : 0-3%; and and/or ZrO ₂ : 0-3%; and/or La ₂ O ₃ : 0-3%; and/or Y ₂ O ₃ : 0-3%; and/or Gd ₂ O ₃ : 0-3%; and /or Nb ₂ O ₅ : 0-3%; and/or WO ₃ : 0-3%; and/or clarifying agent: 0-0.5%.

(8) The optical glass according to any one of (1) to (4), the components of which are expressed in mole percent, wherein: B ₂ O ₃ /SiO ₂ is 0.05 to 0.18; and/or (TiO ₂ +ZnO) /Al ₂ O ₃ is 0.5-7.0; and/or (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) is 3.0-10.0; and/or ZnO/B ₂ O ₃ is 0.2-2.0; and/or (Na ₂ O+K ₂ O)/Al ₂ O ₃ is 1.5 to 10.0; and/or (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.3 to 2.0; and/or (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 1.0 to 10.0.

(9) The optical glass according to any one of (1) to (4), whose components are expressed in mole percentages, wherein: (MgO+CaO+SrO+BaO)/ZnO is 0.5 or less; and/or (MgO+ CaO+SrO+BaO)/Al ₂ O ₃ is 0.8 or less; and/or (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) is 0.5 or less.

(10) The optical glass according to any one of (1) to (4), whose components are expressed in mole percent, and contain: SiO ₂ : 66-75%; and/or B ₂ O ₃ : 5-10%; and/or TiO ₂ : 2-6%; and/or ZnO: 2-8%; and/or Al ₂ O ₃ : 1-6%; and/or Na ₂ O: 5-10%; and/or K ₂ O: 2-6%; and/or La ₂ O ₃ : 0-1%; and/or Y ₂ O ₃ : 0-1%; and/or Gd ₂ O ₃ : 0-1%; and/or Nb ₂ O ₅ : 0-1%; and/or WO ₃ : 0-1%; and/or clarifying agent: 0-0.2%.

(11) The optical glass according to any one of (1) to (4), whose components are expressed in mole percent, wherein: B ₂ O ₃ /SiO ₂ is 0.07 to 0.14; and/or (TiO ₂ +ZnO) /Al ₂ O ₃ is 1.0-5.0; and/or (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) is 4.0-8.0; and/or ZnO/B ₂ O ₃ is 0.4-1.0; and/or (Na ₂ O+K ₂ O)/Al ₂ O ₃ is 2.0 to 7.0; and/or (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.5 to 1.5; and/or (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 2.0 to 7.0.

(12) The optical glass according to any one of (1) to (4), the composition of which is expressed in mole percent, wherein: (MgO+CaO+SrO+BaO)/ZnO is 0.3 or less; and/or (MgO+ CaO+SrO+BaO)/Al ₂ O ₃ is 0.3 or less; and/or (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) is 0.3 or less.

(13) The optical glass according to any one of (1) to (4), wherein the composition is expressed in mole percent, and contains: MgO: 0 to 5%, preferably MgO: 0 to 3%, more preferably MgO: 0 to 0% 2%; and/or CaO: 0-5%, preferably CaO: 0-3%, more preferably CaO: 0-2%; and/or SrO: 0-5%, preferably SrO: 0-3%, more preferably SrO: 0 to 2%; and/or BaO: 0 to 5%, preferably BaO: 0 to 3%, more preferably BaO: 0 to 2%.

(14) The optical glass according to any one of (1) to (4), the components of which are expressed in mole percentages, and are La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O ₃ , Nb ₂ O ₅ , and WO ₃ The total content is 5% or less, preferably 3% or less, and more preferably 1% or less.

(15) The optical glass according to any one of (1) to (4), wherein the component does not contain F; and/or does not contain Ta ₂ O ₅ ; and/or does not contain Li ₂ O; and/or does not contain With _{P2O5 ;} and/or without _ZrO2 .

(16) The optical glass according to any one of (1) to (4), wherein the optical glass has a refractive index of 1.48 to 1.60, preferably 1.50 to 1.58, more preferably 1.51 to 1.56, and an Abbe number of 50 to 50 58, preferably 51-57, more preferably 53-56.

(17) The optical glass according to any one of (1) to (4), wherein the thermal expansion coefficient α _20-300°C of the optical glass is 90×10 ^-7 /K or less, preferably 60×10 ^-7 /K ～90×10 ^-7 /K, more preferably 65×10 ^-7 /K～85×10 ^-7 /K, still more preferably 68×10 ^-7 /K～80×10 ^-7 /K; acid resistance is stable and/or the stability to water action is class 2 or higher, preferably class 1; and/or the glass sample whose stability against alkali action is measured in accordance with the test conditions and requirements of ISO 10629 The weight loss is less than 9 mg, preferably less than 7 mg, more preferably less than 5 mg.

(18) The optical glass according to any one of (1) to (4), which has a light transmittance τ _{360 nm} of 78% or more, preferably 82% or more, and more preferably 85% or more; and/ Or the Young's modulus is 6000×10 ⁷ Pa or more, preferably 6500×10 ⁷ Pa～8500×10 ⁷ Pa, more preferably 7000×10 ⁷ Pa～8000×10 ⁷ Pa; and/or the transition temperature is 610°C Below, it is preferably 500°C to 610°C, more preferably 520°C to 600°C, further preferably 530°C to 580°C; and/or the degree of bubbles is A grade or higher, preferably A ₀ grade or higher, more preferably A ₀₀ ; and/or the streaks are C or higher, preferably B or higher.

(19) A glass preform, made of the optical glass described in any one of (1) to (18).

(20) The optical element is made of the optical glass described in any one of (1) to (18), or made of the glass preform described in (19).

(21) An optical instrument, made of the optical glass described in any one of (1) to (18), or made of the optical element described in (20).

The beneficial effects of the present invention are: through reasonable component design, the optical glass obtained by the present invention has a lower thermal expansion coefficient and excellent chemical stability.

Hereinafter, although embodiment of the optical glass of this invention is demonstrated in detail, this invention is not limited to the following embodiment, It can change suitably within the range of the objective of this invention, and can implement. In addition, although there are cases where descriptions are appropriately omitted regarding overlapping descriptions, this does not limit the gist of the invention. In the following, the optical glass of the present invention may be simply referred to as glass.

[Optical glass]

The range of each component of the optical glass of the present invention will be described below. In this specification, unless otherwise specified, the content of each component and the total content are all expressed in molar percentages relative to the total amount of glass substances in the composition converted into oxides. Here, the "composition in terms of oxides" refers to the case where the oxides, complex salts, hydroxides, etc. used as raw materials of the optical glass composition of the present invention are decomposed and converted into oxides when melted. , and the total molar amount of the oxide is taken as 100%.

Unless the specific case indicates otherwise, the numerical ranges set forth herein include upper and lower limits, "above" and "below" include the endpoints, and all integers and fractions included within the range, without limitation The specific value listed when limiting the range. As used herein, "and/or" is inclusive, eg, "A; and/or B", and means only A, or only B, or both.

<Essential and optional components>

SiO ₂ is one of the main components of the glass. In the glass of the present invention, an appropriate amount of SiO ₂ can ensure that the glass has high water resistance and acid resistance, and can achieve high light transmittance. If the content of SiO ₂ is less than 60%, the water resistance, acid resistance and UV transmittance of the glass are lower than the design requirements. The lower limit of the content of SiO ₂ is preferably 62%, more preferably 66%. If the content of SiO ₂ is higher than 80%, the refractive index of the glass cannot meet the design requirements, the melting temperature of the glass will rise sharply, and it is difficult to obtain high-quality glass in production. Therefore, in the present invention, the content of SiO ₂ is limited to 80% or less, preferably 78% or less, and more preferably 75% or less.

Adding an appropriate amount of B ₂ O ₃ to the glass can transform the structure of the glass into a dense direction, improve the refractive index of the glass, and achieve high water resistance and acid resistance. If the content of B 2 O 3 is less than 3%, the above effect is not obvious. If the content of B ₂ O ₃ is higher than 15%, the water resistance and acid resistance of glass will decrease instead. Therefore, the content of B ₂ O ₃ is limited to 3 to 15%, preferably 4 to 12%, and more preferably 5 to 10%.

In some embodiments of the present invention, the value of B ₂ O ₃ /SiO ₂ will affect the production difficulty of glass. If B ₂ O ₃ /SiO ₂ is less than 0.04, the melting temperature of glass will increase, and the erosion of refractory materials will be aggravated. Introducing more colored impurities and inclusions into the glass will cause the transmittance of the glass to fail to meet the design requirements, and at the same time will lead to an increase in the probability of defects inside the product. If B ₂ O ₃ /SiO ₂ is greater than 0.23, the glass melting temperature will not decrease significantly, and the erosion of refractory materials by B ₂ O ₃ will increase, which will also lead to the introduction of more coloring impurities and inclusions into the glass, resulting in glass The short-wave transmittance does not meet the design requirements, and at the same time, the probability of defects on the surface of the product will increase. Therefore, in the present invention, the value of B ₂ O ₃ /SiO ₂ is preferably 0.04 to 0.23, more preferably 0.05 to 0.18, and further preferably 0.07 to 0.14.

A suitable amount of Al ₂ O ₃ added to the glass can improve the water resistance and acid resistance of the glass, and at the same time can reduce the thermal expansion coefficient of the glass, especially in the presence of alkali metal oxides. If the content of Al ₂ O ₃ is higher than 10%, the Abbe number of the glass is lower than the design expectation. Therefore, the content of Al ₂ O ₃ is limited to more than 0 but less than or equal to 10%, preferably 0.5 to 8%, and more preferably 1 to 6%.

ZnO has a large field strength in divalent metal oxides. Adding ZnO to glass can increase the refractive index of the glass, improve the acid resistance, water resistance and alkali resistance of the glass, and can reduce the thermal expansion coefficient of the glass, especially in the glass containing alkali metals. It is more obvious in the system. If the content of ZnO is less than 0.5%, the above effect is not obvious. If the content of ZnO exceeds 13%, the transition temperature of the glass decreases rapidly, making the glass easy to soften and deform in a high-temperature working environment, and adversely affect the glass devices that need to work at high temperature; in addition, if its content exceeds 13%, The dispersion of glass rises rapidly, and the Abbe number does not meet the design requirements. Therefore, the content of ZnO is limited to 0.5 to 13%, preferably 1 to 10%, and more preferably 2 to 8%.

The inventors have found that when the glass contains B ₂ O ₃ , the presence of ZnO further reduces the melting temperature of the glass and makes it easier to obtain high-quality products. If the value of ZnO/B ₂ O ₃ is lower than 0.1, the above effects will not Obviously; if ZnO/B ₂ O ₃ is higher than 3.0, the transition temperature of the glass decreases rapidly, and the heat resistance cannot meet the design requirements. On the other hand, when the value of ZnO/B ₂ O ₃ is 0.1 to 3.0, the water resistance, acid resistance and alkali resistance of the glass are more excellent than when B ₂ O ₃ is added alone. Therefore, in the present invention, the value of ZnO/B ₂ O ₃ is 0.1 to 3.0, preferably 0.2 to 2.0, and more preferably 0.4 to 1.0.

Adding a suitable amount of TiO ₂ to the glass can increase the refractive index of the glass, further improve the water resistance, acid resistance and alkali resistance of the glass, and at the same time can reduce the thermal expansion coefficient of the glass and improve the thermal shock resistance of the glass. If the content of TiO ₂ Below 0.5%, the above effect is not obvious. If the content of TiO ₂ exceeds 10%, the Abbe number of the glass is lower than the design expectation. On the other hand, the short-wave transmittance of the glass decreases rapidly, especially in the environment where the melting atmosphere is unstable, and it may even cause product batches. There is a big difference. More importantly, high content of TiO ₂ leads to a rapid increase in the refractive index of the glass, which increases the reflection loss of short-wave wavelengths without anti-reflection coating, resulting in a further decrease in short-wave transmittance. Further, the high content of TiO ₂ rapidly increases the dispersion of the glass, resulting in the Abbe number failing to meet the design requirements, resulting in chromatic aberration in the optical system. Therefore, the content of TiO ₂ in the present invention is limited to 0.5 to 10%, preferably 1 to 8%. In some embodiments, taking into account the refractive index of the glass, the Abbe number, and the difficulty of controlling the atmosphere during the melting process, the content of TiO ₂ is more preferably 2-6%.

In some embodiments, if the value of (TiO ₂ +ZnO)/Al ₂ O ₃ is greater than 10.0, the crystallization tendency of the glass increases and the UV transmittance decreases, if the value of (TiO ₂ +ZnO)/Al ₂ O ₃ is low At 0.2, the meltability of the glass decreases, the difficulty of discharging bubbles increases, and the intrinsic quality deteriorates. Therefore, the value of (TiO ₂ +ZnO)/Al ₂ O ₃ is preferably 0.2 to 10.0, the value of (TiO ₂ +ZnO)/Al ₂ O ₃ is more preferably 0.5 to 7.0, and the value of (TiO ₂ +ZnO)/ The value of Al ₂ O ₃ is 1.0 to 5.0.

MgO, CaO, SrO, and BaO are alkaline earth metal oxides. Adding them to glass can increase the refractive index and transition temperature of the glass, and adjust the stability and thermal expansion coefficient of the glass. However, the addition of alkaline earth metal oxides leads to a rapid increase in the Young's modulus of the glass. When the thermal expansion coefficient of the glass material is the same, the glass with a lower Young's modulus has better thermal shock resistance. Therefore, considering the above-mentioned factors, the total addition amount of the alkaline earth metal oxides, MgO+CaO+SrO+BaO, is preferably 10% or less, and more preferably 5% or less. In some embodiments, if the stability, thermal expansion coefficient and transition temperature of the glass meet the design requirements, it is further preferred not to add alkaline earth metal oxides.

In some applications, a higher refractive index and a higher Abbe number are required to achieve optical system matching, or a higher transition temperature is required, which requires the addition of small amounts of alkaline earth metal oxides. When adding alkaline earth metal oxides, in order to avoid the rapid decline of the water resistance, acid resistance and alkali resistance of the glass, it can be considered to add MgO, CaO, SrO, BaO individually or in combination in the order. If the content of MgO, CaO, SrO, BaO and other alkaline earth metal oxides alone exceeds 5%, the anti-devitrification performance of the glass will decline rapidly, and it is difficult to obtain large-diameter high-quality products. Therefore, the contents of MgO, CaO, SrO, and BaO are respectively limited to 5% or less, preferably 3% or less, and more preferably 2% or less.

The inventors have found that, in some embodiments, if there is a certain amount of alkaline earth metal oxides in the glass, the ZnO content can be adjusted to reduce the loss of chemical stability and thermal shock resistance of the glass. When the value of (MgO+CaO+SrO+BaO)/ZnO is below 1.0, preferably below 0.5, more preferably below 0.3, a higher refractive index can be easily obtained, and the chemical stability, Glass with thermal expansion coefficient and thermal shock resistance.

In some embodiments of the present invention, by making the ratio of alkaline earth metal oxide to Al ₂ O ₃ (MgO+CaO+SrO+BaO)/Al ₂ O ₃ below 1.5, the devitrification resistance and chemical resistance of the glass can be improved For stability and suppressing an increase in thermal expansion coefficient, (MgO+CaO+SrO+BaO)/Al ₂ O ₃ is preferably 0.8 or less, and more preferably (MgO+CaO+SrO+BaO)/Al ₂ O ₃ is 0.3 or less.

Li ₂ O, Na ₂ O and K ₂ O are alkali metal oxides, and in the glass of the present invention, their content is closely related to the thermal expansion coefficient, chemical stability and intrinsic quality of the glass.

Intrinsic qualities used in optical systems can often be described in terms of bubbleness and striation.

The addition of Li ₂ O to the glass can reduce the melting temperature of the glass, increase the bubble degree of the glass, and at the same time, compared with the other two alkali metal oxides, the chemical stability loss of the glass is minimal. However, if the content of Li ₂ O exceeds 5%, the solidification speed of the glass during the forming process, that is, the process of cooling the glass liquid from liquid to solid, will be slow, which is unfavorable for the production of large-scale and high-quality products (such as Production of products with a width or diameter greater than 340 mm and a thickness greater than 40 mm is prone to unqualified streaks and internal devitrification). On the other hand, it will also cause the transition temperature of the glass to drop, and the heat resistance will not meet the design requirements. Therefore, the content of Li ₂ O is limited to 5% or less, preferably 3% or less, and more preferably, no Li ₂ O is added.

In the present invention, by introducing more than 2% Na ₂ O, the high-temperature viscosity of the glass can be reduced, and it is easier to obtain large-diameter high-quality products. However, if the content of Na ₂ O exceeds 15%, the refractive index of the glass decreases, and the chemical stability of the glass decreases rapidly, which cannot meet the design requirements. Therefore, the content of Na ₂ O is limited to 2 to 15%, preferably 3 to 12%, and more preferably 5 to 10%.

Adding an appropriate amount of K ₂ O to the glass can reduce the high temperature viscosity of the glass and improve the bubble degree of the glass, especially in the case of coexisting with Na ₂ O, the addition of an appropriate amount of K ₂ O to the glass will not significantly damage the glass. chemical stability. However, if the content of K ₂ O exceeds 10%, the water resistance, acid resistance and alkali resistance of the glass are seriously deteriorated. If the content of K ₂ O is less than 1%, the effect of reducing the high temperature viscosity is not obvious. Therefore, the content of K ₂ O is limited to 1 to 10%, preferably 2 to 8%, and more preferably 2 to 6%.

In the present invention, if the value of (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is lower than 0.2, the free oxygen in the glass system is insufficient, causing components such as B ₂ O ₃ and ZnO to enter the glass mesh The probability of the road is reduced, resulting in a decrease in chemical stability. If the value of (Na ₂ O + K ₂ O)/(B ₂ O ₃ +ZnO) is greater than 3.0, there will be excess free oxygen in the glass system, which will lead to a sharp decline in the chemical stability of the glass, and the thermal expansion coefficient of the glass exceeds the design requirements. Therefore, when the value of (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is between 0.2 and 3.0, preferably between 0.3 and 2.0, and more preferably between 0.5 and 1.5, the Chemical stability and expansion coefficient are the most balanced.

In the present invention, if the value of (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is greater than 15.0, the alkali resistance of the glass decreases and the thermal expansion coefficient increases; if (B ₂ O ₃ +K ₂ O)/Al When the value of ₂ O ₃ is less than 0.8, the meltability of the glass decreases and the transition temperature increases. Therefore, the value of (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is preferably 0.8 to 15.0, more preferably the value of (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 1.0 to 10.0, and further The value of (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is preferably 2.0 to 7.0.

In the prior art, it is generally believed that the addition of alkaline earth metal oxides MgO, CaO, SrO, BaO, etc. to glass is more conducive to the improvement of chemical stability than alkali metal oxides Li ₂ O, Na ₂ O, K ₂ O, etc. The present invention It was found through experiments that in the glass of this system, because the ability of alkaline earth metal oxides to provide free oxygen is weaker than that of alkali metal oxides, when the value of (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) When it is greater than 1.0, the internal network of the glass will be seriously broken, thereby reducing the chemical stability of the glass, especially when immersed in a strong alkaline solution, if (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O ) is greater than 1.0, the alkaline earth metal ions are more likely to be eroded and precipitated. Therefore, the value of (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) is preferably 1.0 or less, more preferably 0.5 or less, and still more preferably 0.3 or less.

In the present invention, in order to obtain a suitable thermal expansion coefficient, it is necessary to add Na ₂ O and K ₂ O to the glass, but it will lead to a decrease in the chemical stability of the glass. The inventors have found through research that when Al ₂ O ₃ exists in the glass, the type and relative content of the alkali metal oxides will change the microstructure of the glass and have a greater impact on the chemical stability of the glass. In some embodiments, when the value of (Na ₂ O+K ₂ O)/Al ₂ O ₃ is satisfied in the range of 1.0 to 12.0, preferably 1.5 to 10.0, more preferably 2.0 to 7.0, the glass can achieve the desired thermal expansion coefficient At the same time, it can also improve the chemical stability of the glass.

In some embodiments, in order to obtain high-quality glass products, when the value of (SiO ₂ +TiO ₂ )/(Na ₂ O + ZnO) is greater than 15.0, the glass becomes difficult to melt and clarify, and there are bubbles and inclusions in the glass. It is difficult to obtain glass with a bubble degree above A ₀ level, and the internal streaks of the glass are serious. If the value of (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) is lower than 2.5, the thermal expansion coefficient of the glass increases rapidly, exceeding the design requirements. Therefore, it is preferable to control the value of (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) to be between 2.5 and 15.0, more preferably between 3.0 and 10.0, and even more preferably between 4.0 and 8.0.

A suitable amount of P ₂ O ₅ added to the glass can increase the strength of the glass, especially when chemical strengthening is required. However, if its content exceeds 5%, a differential phase is easily generated inside the glass, which greatly increases the molding temperature of the glass, and it is difficult to obtain high-quality glass products that meet the requirements of optical imaging. Therefore, the content of P ₂ O ₅ is limited to 0 to 5%, preferably 0 to 3%. In some embodiments, when the strength of the glass is designed to meet the usage requirements, it is more preferable not to add P ₂ O ₅ .

Adding an appropriate amount of ZrO ₂ to the glass can improve the chemical stability and thermal shock resistance of the glass, and at the same time increase the refractive index of the glass, but its characteristic is that it will significantly increase the melting temperature of the glass. If its content is higher than 5%, Inclusion defects are prone to occur in glass. Therefore, the content of ZrO ₂ is limited to 5% or less, preferably 3% or less. In some embodiments, when the chemical stability and strength of the glass are excessive, it is more preferable not to add ZrO ₂ .

In some embodiments of the present invention, when it is necessary to increase the refractive index and transition temperature of the glass, an appropriate amount of oxides such as La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O ₃ , Nb ₂ O ₅ , WO ₃ and the like can be added , but when its single or combined content exceeds 5%, the anti-devitrification performance and short-wave transmittance of the glass deteriorate. Therefore, the contents of La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O ₃ , Nb ₂ O ₅ , and WO ₃ are respectively 5% or less, preferably 3% or less, more preferably 1% or less, and further preferably not contained. Further, the total content of La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O ₃ , Nb ₂ O ₅ , and WO ₃ is preferably 5% or less, more preferably 3% or less, and still more preferably 1% or less.

In some embodiments of the present invention, by adding 0-1% of one or more components of Sb ₂ O ₃ , SnO ₂ , SnO, NaCl, sulfate and CeO ₂ as a clarifying agent, preferably Sb ₂ O ₃ is used As a clarifying agent, it can improve the clarifying effect of the glass, preferably 0-0.5% of the clarifying agent is added, more preferably 0-0.2% of the clarifying agent is added.

The addition of F into the glass will increase the volatilization of the glass raw material, which is likely to cause environmental pollution and deterioration of the glass streak. Therefore, the glass of the present invention preferably does not contain F. The addition of Ta ₂ O ₅ to the glass will greatly increase the refractive index and cost of the glass, and deteriorate the melting performance of the glass, so it is preferred that the glass of the present invention does not contain Ta ₂ O ₅ .

<Ingredients that should not be contained>

Oxides of Th, Cd, Tl, Os, Be, and Se tend to be used in a controlled manner as harmful chemical substances in recent years, not only in the glass manufacturing process, but also in the processing process and disposal after productization. Action is required. Therefore, when considering the influence on the environment, it is preferable not to actually contain them except for unavoidable mixing. Thereby, the glass becomes practically free of substances that pollute the environment. Therefore, the glass of the present invention can be manufactured, processed, and discarded without taking special measures for environmental measures.

In order to achieve environmental friendliness, the glass of the present invention does not contain As ₂ O ₃ and PbO. Although As ₂ O ₃ has the effect of eliminating bubbles and preventing glass coloration, the addition of As ₂ O ₃ will increase the platinum erosion of the glass to the furnace, especially the platinum furnace, resulting in more platinum ions entering the glass. The service life of the platinum furnace is adversely affected. PbO can significantly improve the high refractive index and high dispersion properties of glass, but both PbO and As ₂ O ₃ are substances that cause environmental pollution.

"Does not contain", "does not add" and "0%" as described herein means that the compound, molecule or element is not intentionally added to the glass of the present invention as a raw material; however, as a raw material and/or equipment for producing glass, There may be some unintentionally added impurities or components, which may be contained in a small or trace amount in the final glass, and this situation is also within the protection scope of the patent of the present invention.

Next, the performance of the optical glass of this invention is demonstrated.

<Refractive index and Abbe number>

The refractive index (nd) and Abbe number (ν _d ) of optical glass are tested according to the methods specified in GB/T 7962.1-2010.

The lower limit of the refractive index (nd) of the optical glass of the present invention is 1.48, preferably the lower limit is 1.50, more preferably the lower limit is 1.51, and the upper limit of the refractive index (nd) is 1.60, preferably 1.58, more preferably 1.56;

The lower limit of the Abbe number (ν _d ) is 50, preferably 51, and more preferably 53, and the upper limit of the Abbe number (ν _d ) is 58, preferably 57, and more preferably 56.

<Acid resistance stability>

The acid resistance stability (DA) (powder method) of optical glass is tested according to the method specified in GB/T ₁₇₁₂₉ . Acid resistance stability is sometimes referred to herein simply as acid resistance or acid resistance stability.

The acid resistance stability (D _A ) of the optical glass of the present invention is two or more types, preferably one type.

<Water resistance stability>

The water resistance stability (D _W ) (powder method) of optical glass is tested according to the method specified in GB/T 17129. Water resistance stability is sometimes referred to herein simply as water resistance or water resistance stability.

The water resistance stability (D _W ) of the optical glass of the present invention is two or more types, preferably one type.

<Alkali resistance stability>

The stability against alkali action of optical glass is measured according to the test conditions and requirements of ISO 10629, and is expressed as the weight loss of the glass sample. Alkali action stability is sometimes referred to herein simply as alkali resistance or alkali stability.

The glass was processed into a test sample of 30 mm × 30 mm × 2 mm, polished on six sides, and put into 2000 ml of NaOH solution, the concentration of the NaOH solution was 0.01 mol/L, the pH value was 12.0, and the test process was timed Monitor the pH value of the test solution with a pH meter, and replace the reaction test solution in time. After eroding at 50 °C for 100 hours, use an electronic balance to measure the weight loss of the sample, and the weight loss is expressed in mg.

The weight loss of the optical glass of the present invention according to the above test method is less than 9 mg, preferably less than 7 mg, more preferably less than 5 mg.

<Coefficient of Thermal Expansion>

The thermal expansion coefficient mentioned in the present invention refers to the average thermal expansion coefficient of glass at 20-300 °C, expressed as α _{20-300 °C} , and tested according to the method specified in GB/T7962.16-2010.

The upper limit of the average thermal expansion coefficient (α _{20-300 ℃} ) of the optical glass of the present invention is 90×10 ^-7 /K, preferably 85×10 ^-7 /K, and more preferably 80×10 ^-7 /K. The lower limit of the thermal expansion coefficient (α _{20-300 °C} ) is 60×10 ^-7 /K, preferably 65×10 ^-7 /K, and more preferably 68×10 ^-7 /K.

<Light transmittance>

The light transmittance mentioned in the present invention refers to the internal transmittance of a glass sample with a thickness of 10 mm at 360 nm, expressed as τ _{360 nm} , and tested according to the method specified in GB/T7962.12-2010.

The optical glass of the present invention has an internal transmittance at 360 nm (τ _{360 nm} ) of 78% or more, preferably 82% or more, and more preferably 85% or more.

<Transition temperature>

The glass transition temperature (T _g ) is tested according to the method specified in GB/T7962.16-2010.

The upper limit of the transition temperature (T _g ) of the glass of the present invention is 610°C, preferably the upper limit is 600°C, more preferably the upper limit is 580°C, and the lower limit of the transition temperature (T _g ) is 500°C, preferably the lower limit is 520°C, more preferably the lower limit is 530°C.

<Young's modulus>

The Young's modulus (E) of glass is calculated using the following formula:

in,

where:

E is Young's modulus, Pa;

G is the shear modulus, Pa;

V _T is the longitudinal wave velocity, m/s;

V _S is the shear wave velocity, m/s;

ρ is the glass density, g/cm ³ .

The lower limit of the Young's modulus (E) of the optical glass of the present invention is 6000×10 ⁷ Pa, preferably the lower limit is 6500×10 ⁷ Pa, more preferably the lower limit is 7000×10 ⁷ Pa, and the upper limit of the Young’s modulus (E) is 8500×10 ⁷ Pa, preferably the upper limit is 8000×10 ⁷ Pa.

＜Bubble degree＞

The bubble degree of optical glass is tested according to the test method specified in GB/T7962.8-2010.

The bubble degree of the optical glass of the present invention is A-level or higher, preferably _A0 -level or higher, and more preferably _A00 -level.

＜Stripeness＞

The fringe degree of optical glass is measured according to the method specified in MLL-G-174B. The method is to use a streak instrument composed of a point light source and a lens to compare and inspect the standard sample from the direction where the streak is most easily seen. There are no visible streaks under the conditions, B grades are fine and scattered stripes under the specified detection conditions, C grades are slight parallel stripes under the specified detection conditions, and D grades are rough stripes under the specified detection conditions.

The stripes of the optical glass of the present invention are C-rank or higher, preferably B-rank or higher.

[Production method]

The manufacturing method of the optical glass of the present invention is as follows: the glass of the present invention is produced by using conventional raw materials and conventional processes, using carbonates, nitrates, sulfates, hydroxides, oxides, etc. The furnace charge is put into a melting furnace at 1300-1500 °C for melting, and after clarification, stirring and homogenization, a homogeneous molten glass without bubbles and no undissolved substances is obtained. The molten glass is cast in a mold and annealed made. Those skilled in the art can appropriately select raw materials, process methods and process parameters according to actual needs.

[Glass Preforms and Optical Components]

A glass preform can be produced from the optical glass produced by using, for example, a means of grinding, or a means of press forming such as reheat press forming and precision press forming. That is, a glass preform can be produced by subjecting optical glass to mechanical processing such as grinding and polishing, or by producing a preform for press-molding from optical glass, reheating the preform, and then grinding the preform. Glass preforms are produced by machining, or by precision stamping of preforms produced by grinding.

It should be noted that the means for preparing the glass preform is not limited to the above-mentioned means. As described above, the optical glass of the present invention is useful for various optical elements and optical designs, and it is particularly preferable to form a preform from the optical glass of the present invention, and to perform reheat press molding, precision press molding, etc. using the preform, Manufacture of optical components such as lenses and prisms.

Both the glass preform and the optical element of the present invention are formed from the optical glass of the present invention described above. The glass preform of the present invention has the excellent characteristics of optical glass; the optical element of the present invention has the excellent characteristics of optical glass, and can provide various optical elements such as lenses and prisms with high optical value.

Examples of lenses include various lenses such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses whose lens surfaces are spherical or aspherical.

[Optical Instruments]

The optical element formed by the optical glass of the present invention can be used to make optical instruments such as photographic equipment, imaging equipment, display device and monitoring equipment, and can also be applied to the fields of vehicle lighting, display, imaging and the like.

Example

<Example of Optical Glass>

In order to further clearly illustrate and illustrate the technical solutions of the present invention, the following non-limiting Examples 1-20 are provided.

In this Example, the optical glass which has the composition shown in Table 1 - Table 2 was obtained by the manufacturing method of the said optical glass. In addition, the properties of each glass were measured by the test method according to the present invention, and the measurement results are shown in Tables 1 to 2. [Table 1] Composition (mol%) 1# 2# 3# 4# 5# 6# 7# 8# 9# 10# _SiO2 69.6 69.5 65 60 63.5 69.5 69.5 73.5 60 69.4 B ₂ O ₃ 7.7 7.7 7 12.9 7.7 7.7 5.7 3 10 7.8 Al ₂ O ₃ 2.6 3 3 3 8 3.5 5 3.7 3 3 P ₂ O ₅ 0 0 0 0 0 0.5 0 0 0 0 La ₂ O ₃ 0 0 0 0 0 0 0 0 1 0 Y ₂ O ₃ 0 0 0 0 0 0 0 0 0 0 Gd ₂ O ₃ 0 0 0 0 0 0 0 0 1 0 TiO ₂ 3.5 3.5 4 4 3.5 3 3.5 3.5 2 3.5 ZrO ₂ 0 0 0 0 0 0 0 0 0.4 0 Nb ₂ O ₅ 0 0 0 0 0 0 0 0 0 0 WO ₃ 0 0 0 0 0 0 0 0 0 0 ZnO 4.4 4.5 4.5 4.5 7.5 4 4.5 4.5 4.5 4.5 MgO 0 0 3 0 0 0 0 0 0 0 BaO 0 0 0 1 0 0 0 0 0 0 SrO 0 0 0 0 0 0 0 0 0 0 CaO 0 0 0 1 0 0 0 0 2 0 Li ₂ O 0.5 0 0 0 0 0 0 0 0 0 Na ₂ O 7 7.1 8.5 8.5 5.1 7.1 7.1 7.1 10 7.1 K ₂ O 4.6 4.6 4.9 5 4.6 4.6 4.6 4.6 6 4.6 clarifying agent 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 B ₂ O ₃ /SiO ₂ 0.11 0.11 0.11 0.22 0.12 0.11 0.08 0.04 0.17 0.11 (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ 4.73 4.1 3.97 5.97 1.54 3.51 2.06 2.05 5.33 4.13 (TiO ₂ +ZnO)/Al ₂ O ₃ 3.04 2.67 2.83 2.83 1.38 2 1.6 2.16 2.17 2.67 ZnO/B ₂ O ₃ 0.57 0.6 0.6 0.3 1 0.5 0.8 1.5 0.5 0.6 MgO+CaO+SrO+BaO 0 0 3 2 0 0 0 0 2 0 (MgO+CaO+SrO+ BaO)/ZnO 0 0 0.7 0.4 0 0 0 0 0.4 0 (MgO+CaO+SrO+BaO) /Al ₂ O ₃ 0 0 1 0.67 0 0 0 0 0.67 0 (Na ₂ O+K ₂ O)/Al ₂ O ₃ 4.46 3.9 4.5 4.5 1.2 3.3 2.3 3.2 5.3 3.9 (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) 0.96 0.96 1.17 0.78 0.64 1 1.15 1.56 1.1 0.95 (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) 0 0 0.35 0.24 0 0 0 0 0.2 0 (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) 6.41 6.29 5.31 4.92 5.32 6.53 6.29 6.64 4.28 6.28 nd 1.52760 1.52679 1.53519 1.55170 1.53375 1.52028 1.52331 1.51638 1.54577 1.52703 vd 54.28 54.45 51.90 52.58 53.64 56.07 53.96 53.67 55.03 54.47 α _{20-300 ℃} (×10 ^-7 /K) 71 73 77 80 68 73 69 67 84 73 τ _360nm (%) 86 87.2 87.1 87.5 87.1 87.4 87.2 86.8 87.9 87.2 T _g (℃) 547 557 540 525 568 560 575 589 535 557 E (×10 ⁷ Pa) 7200 7220 7380 7150 7450 7250 7300 7360 7120 7220 D _W Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 D _A Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Alkali resistance (mg) 3 3.2 3.6 4 4.1 2.7 2.7 4.3 4.1 3.2 Bubble degree A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ streak B B B C B B B C B B [Table 2] Composition (mol%) 11# 12# 13# 14# 15# 16# 17# 18# 19# 20# _SiO2 63 68.5 67.5 62.1 65.4 70 67 69.3 69 68.1 B ₂ O ₃ 7.7 7.7 7.7 11 7.7 8 9 7.4 8.4 7.5 Al ₂ O ₃ 3 3 2 3.5 3 2 3 3.2 2.5 4 P ₂ O ₅ 1 1 0 0 0 0 0 0 0 0 La ₂ O ₃ 1 0 0 0 0 0 0 0 0 0 Y ₂ O ₃ 4 0 0 0 0 0 0 0 0 0 Gd ₂ O ₃ 0.5 0 0 0 0 0 0 0 0 0 TiO ₂ 3.5 3.5 5 4 3.5 3.5 3.5 3.7 3.2 4 ZrO ₂ 0 0 0 0 0 1 0 0 0 0 Nb ₂ O ₅ 0 0 0 0 0 0 0 0 0 0 WO ₃ 0 0 0 0 0 0 0 0 0 0 ZnO 4.5 4.5 6 5 4.5 3.5 4.5 4.7 4.4 5 MgO 0 0 0 0 3 0 0 0 0 0 BaO 0 0 0 0 0 0 2 0 0 0 SrO 0 0 0 0 0 0 0 0 1 0 CaO 0 0 0 0 1 0 2 0 0 0 Li ₂ O 0 0 0 0 0 0 0 1 0 0 Na ₂ O 7.1 7.1 6.8 9.3 7.2 6.8 7.1 7.2 6.8 6.7 K ₂ O 4.6 4.6 4.9 5 4.6 5.1 1.8 3.4 4.6 4.6 clarifying agent 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 B ₂ O ₃ /SiO ₂ 0.12 0.11 0.11 0.18 0.12 0.11 0.13 0.11 0.12 0.11 (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ 4.1 4.1 6.3 4.57 4.1 6.55 3.6 3.38 5.2 3.03 (TiO ₂ +ZnO)/Al ₂ O ₃ 2.67 2.67 5.5 2.57 2.67 3.5 2.67 2.63 3.04 2.25 ZnO/B ₂ O ₃ 0.58 0.6 0.8 0.5 0.6 0.4 0.5 0.6 0.5 0.7 MgO+CaO+SrO+BaO 0 0 0 0 4 0 4 0 1 0 (MgO+CaO+SrO+BaO)/ZnO 0 0 0 0 0.9 0 0.9 0 0.2 0 (MgO+CaO+SrO+BaO)/Al ₂ O ₃ 0 0 0 0 1.33 0 1.33 0 0.4 0 (Na ₂ O+K ₂ O)/Al ₂ O ₃ 3.9 3.9 5.9 4.1 3.9 6 3 3.3 4.6 2.8 (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) 0.96 0.96 0.85 0.89 0.97 1.03 0.66 0.88 0.89 0.9 (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) 0 0 0 0 0.56 0 0.56 0 0.15 0 (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) 5.73 6.21 5.66 4.62 5.89 7.14 6.08 6.13 6.45 6.16 nd 1.56592 1.52504 1.54425 1.54326 1.53335 1.52894 1.53981 1.52989 1.52801 1.53238 vd 53.43 54.67 51.39 52.48 53.39 54.35 54.19 53.86 55.07 52.99 α _{20-300 ℃} (×10 ^-7 /K) 78 73 67 79 75 74 69 71 72 70 τ _{360 nm} (%) 85.7 86.1 85.1 88.1 87.1 87.4 87 87.2 86.8 87.5 T _g (℃) 592 550 563 526 568 561 570 537 560 574 E (×10 ⁷ Pa) 7720 7140 7340 7110 7460 7220 7360 7250 7260 7310 D _W Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 D _A Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Alkali resistance (mg) 2.2 3 2.1 3.8 3.2 2.9 3 2.8 3 3.1 Bubble degree A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ streak B B B B C B B B C B

<Example of glass preform>

A concave meniscus lens, a convex meniscus lens, and a biconvex lens are produced by using the glass obtained in the optical glass Examples 1 to 20, for example, by means of grinding, or by means of press molding such as reheat press molding and precision press molding. , Bi-concave lenses, plano-convex lenses, plano-concave lenses and other lenses, prisms and other prefabricated parts.

<Optical element example>

These preforms obtained in the above-mentioned glass preform examples are annealed, and the internal deformation of the glass is reduced while fine-tuning is performed, so that the optical properties such as the refractive index can reach desired values.

Next, each preform is ground and polished to produce various lenses and prisms such as a concave meniscus lens, a convex meniscus lens, a biconvex lens, a biconcave lens, a plano-convex lens, and a plano-concave lens. An antireflection film may also be coated on the surface of the obtained optical element.

<Optical Instrument Example>

The optical elements produced by the above-mentioned optical element embodiments are optically designed and formed by using one or more optical elements to form optical components or optical elements, which can be used for example in imaging equipment, sensors, microscopes, medical technology, digital projection, Optical communication technology/information transmission, optics/illumination in the automotive field, lithography, excimer lasers, wafers, computer chips, and integrated circuits and electronic devices including such circuits and wafers, or used in the automotive field, Monitoring of camera equipment and devices in the field of security.

Claims (33)

An optical glass, wherein its components are expressed in molar percentage, containing: SiO ₂ : 60-80%; B ₂ O ₃ : 3-15%; TiO ₂ : 0.5-10%; ZnO: 0.5-13%; Al ₂ O ₃ : greater than 0 but less than or equal to 10%; Na ₂ O: 2~15%; K ₂ O: 1~10%, wherein (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.2 to 3.0, and (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 0.8 to 15.0. The optical glass according to claim 1, wherein its components are expressed in mole percent, and further contains: MgO+CaO+SrO+BaO: 0~10%; and/or Li ₂ O: 0~5%; and/ or P ₂ O ₅ : 0~5%; and/or ZrO ₂ : 0~5%; and/or La ₂ O ₃ : 0~5%; and/or Y ₂ O ₃ : 0~5%; and/or or Gd ₂ O ₃ : 0~5%; and/or Nb ₂ O ₅ : 0~5%; and/or WO ₃ : 0~5%; and/or clarifying agent: 0~1%. An optical glass, which contains SiO ₂ , B ₂ O ₃ , ZnO, Al ₂ O ₃ , Na ₂ O and K ₂ O, the composition of which is expressed in mole percentage, (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.2~3.0, (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 0.8~15.0, the refractive index of the optical glass is 1.48~1.60, and the Abbe number is 50~58 , the thermal expansion coefficient is below 90×10 ^-7 /K. The optical glass according to claim 3, wherein its components are expressed in molar percentage, and contain: SiO ₂ : 60-80%; B ₂ O ₃ : 3-15%; TiO ₂ : 0.5-10%; ZnO: 0.5~13%; Al ₂ O ₃ : greater than 0 but less than or equal to 10%; Na ₂ O: 2~15%; K ₂ O: 1~10%; MgO+CaO+SrO+BaO: 0~10%; Li ₂ O: 0~5%; P ₂ O ₅ : 0~5%; ZrO ₂ : 0~5%; La ₂ O ₃ : 0~5%; Y ₂ O ₃ : 0~5%; Gd ₂ O ₃ : 0~5%; Nb ₂ O ₅ : 0~5%; WO ₃ : 0~5%; clarifying agent: 0~1%. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, wherein: B ₂ O ₃ /SiO ₂ is 0.04-0.23; and/or (TiO ₂ +ZnO) /Al ₂ O ₃ is 0.2-10.0; and/or (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) is 2.5-15.0; and/or ZnO/B ₂ O ₃ is 0.1-3.0; and/or (Na ₂ O+K ₂ O)/Al ₂ O ₃ is 1.0 to 12.0. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, wherein: (MgO+CaO+SrO+BaO)/ZnO is 1.0 or less; and/or (MgO+ CaO+SrO+BaO)/Al ₂ O ₃ is 1.5 or less; and/or (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) is 1.0 or less. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percentages, and contain: SiO ₂ : 62-78%; and/or B ₂ O ₃ : 4-12%; and/or TiO ₂ : 1-8%; and/or ZnO: 1-10%; and/or Al ₂ O ₃ : 0.5-8%; and/or Na ₂ O: 3-12%; and/or K ₂ O: 2~8%; and/or MgO+CaO+SrO+BaO: 0~5%; and/or Li ₂ O: 0~3%; and/or P ₂ O ₅ : 0~3%; and and/or ZrO ₂ : 0~3%; and/or La ₂ O ₃ : 0~3%; and/or Y ₂ O ₃ : 0~3%; and/or Gd ₂ O ₃ : 0~3%; and /or Nb ₂ O ₅ : 0~3%; and/or WO ₃ : 0~3%; and/or clarifying agent: 0~0.5%. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, wherein: B ₂ O ₃ /SiO ₂ is 0.05-0.18; and/or (TiO ₂ +ZnO) /Al ₂ O ₃ is 0.5-7.0; and/or (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) is 3.0-10.0; and/or ZnO/B ₂ O ₃ is 0.2-2.0; and/or (Na ₂ O+K ₂ O)/Al ₂ O ₃ is 1.5 to 10.0; and/or (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.3 to 2.0; and/or (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 1.0 to 10.0. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, wherein: (MgO+CaO+SrO+BaO)/ZnO is less than 0.5; and/or (MgO+ CaO+SrO+BaO)/Al ₂ O ₃ is 0.8 or less; and/or (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) is 0.5 or less. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percentages, and contain: SiO ₂ : 66-75%; and/or B ₂ O ₃ : 5-10%; and/or TiO ₂ : 2~6%; and/or ZnO: 2~8%; and/or Al ₂ O ₃ : 1~6%; and/or Na ₂ O: 5~10%; and/or K ₂ O: 2~6%; and/or La ₂ O ₃ : 0~1%; and/or Y ₂ O ₃ : 0~1%; and/or Gd ₂ O ₃ : 0~1%; and/or Nb ₂ O ₅ : 0~1%; and/or WO ₃ : 0~1%; and/or clarifying agent: 0~0.2%. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, wherein: B ₂ O ₃ /SiO ₂ is 0.07-0.14; and/or (TiO ₂ +ZnO) /Al ₂ O ₃ is 1.0-5.0; and/or (SiO ₂ +TiO ₂ )/(Na ₂ O+ZnO) is 4.0-8.0; and/or ZnO/B ₂ O ₃ is 0.4-1.0; and/or (Na ₂ O+K ₂ O)/Al ₂ O ₃ is 2.0 to 7.0; and/or (Na ₂ O+K ₂ O)/(B ₂ O ₃ +ZnO) is 0.5 to 1.5; and/or (B ₂ O ₃ +K ₂ O)/Al ₂ O ₃ is 2.0 to 7.0. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, wherein: (MgO+CaO+SrO+BaO)/ZnO is 0.3 or less; and/or (MgO+ CaO+SrO+BaO)/Al ₂ O ₃ is 0.3 or less; and/or (MgO+CaO+SrO+BaO)/(Na ₂ O+K ₂ O) is 0.3 or less. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percentages, and contain: MgO: 0~5%; and/or CaO: 0~5%; and/or SrO : 0~5%; and/or BaO: 0~5%. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, and contain: MgO: 0~3%; and/or CaO: 0~3%; and/or SrO : 0~3%; and/or BaO: 0~3%. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, and contain: MgO: 0~2%; and/or CaO: 0~2%; and/or SrO : 0~2%; and/or BaO: 0~2%. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, and the components of La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O ₃ , Nb ₂ O ₅ , and WO ₃ are The total content is 5% or less. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, and the components of La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O ₃ , Nb ₂ O ₅ , and WO ₃ are The total content is 3% or less. The optical glass according to any one of claims 1 to 4, wherein its components are expressed in mole percent, and the components of La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O ₃ , Nb ₂ O ₅ , and WO ₃ are The total content is 1% or less. The optical glass according to any one of claims 1 to 4, wherein its components do not contain F; and/or do not contain Ta ₂ O ₅ ; and/or do not contain Li ₂ O; and/or do not contain With _{P2O5 ;} and/or without _ZrO2 . The optical glass according to any one of claims 1 to 4, wherein the optical glass has a refractive index of 1.48-1.60; and an Abbe number of 50-58. The optical glass according to any one of claims 1 to 4, wherein the optical glass has a refractive index of 1.50 to 1.58, and an Abbe number of 51 to 57. The optical glass according to any one of claims 1 to 4, wherein the optical glass has a refractive index of 1.51 to 1.56, and an Abbe number of 53 to 56. The optical glass according to any one of claims 1 to 4, wherein the thermal expansion coefficient α _20-300°C of the optical glass is 90×10 ^-7 /K or less, and the acid resistance stability is class 2 or higher ; and/or the water resistance stability is class 2 or more; and/or the alkali resistance stability is measured in accordance with the test conditions and requirements of ISO 10629, and the weight loss of the glass sample is less than 9 mg. The optical glass according to any one of claims 1 to 4, wherein the thermal expansion coefficient α _20-300°C of the optical glass is 60×10 ^-7 /K~90×10 ^-7 /K; acid resistance Class 1 stability; and/or Class 1 stability to water; and/or stability to alkali The glass sample has a weight loss of less than 7 mg when measured in accordance with the test conditions and requirements of ISO 10629. ^and _/ ^_ Or the stability against alkali action is measured in accordance with the test conditions and requirements of ISO 10629, and the weight loss of the glass sample is less than 5 mg. The optical glass according to any one of claims 1 to 4, wherein the thermal expansion coefficient α _20-300°C of the optical glass is 68×10 ^-7 /K to 80×10 ^-7 /K. The optical glass according to any one of claims 1 to 4, wherein the optical glass has a light transmittance τ _360nm of 78% or more; and/or a Young's modulus of 6000×10 ⁷ Pa or more; and and/or the transition temperature is below 610°C; and/or the degree of bubbles is grade A or above; and/or the streak is grade C or above. The optical glass according to any one of claims 1 to 4, wherein the optical transmittance τ _360nm of the optical glass is 82% or more; and/or the Young's modulus is 6500×10 ⁷ Pa~8500× 10 ⁷ Pa; and/or the transition temperature is 500°C to 610°C; and/or the degree of bubbles is A ₀ class or higher; and/or the streak is B class or higher. The optical glass according to any one of claims 1 to 4, wherein the optical glass has a light transmittance τ _360nm of 85% or more; and/or a Young's modulus of 7000×10 ⁷ Pa~8000× 10 ⁷ Pa; and/or a transition temperature of 520°C to 600°C; and/or a bubble degree of A ₀₀ grade. The optical glass according to any one of claims 1 to 4, wherein the transition temperature of the optical glass is 530°C to 580°C. A glass preform made of the optical glass according to any one of claims 1 to 30. An optical element made of the optical glass according to any one of claims 1 to 30, or made of the glass preform according to claim 31. An optical instrument made of the optical glass according to any one of claims 1 to 30, or made of the optical element according to claim 32.