Glass for radiation and / or particle detectors

Abstract

To provide a glass suitable for radiation and / or particle detectors, in particular neutron detectors, UV detectors or neutrino detectors.SOLUTION: The foregoing problem is solved by a glass having a transmittance (at a reference thickness of 1.0 mm) of at least 65.0% at a wavelength of 260 nm, wherein the amount of ZrO2 in the glass is less than 150 ppm.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to glasses for radiation detectors, in particular neutron, UV and neutrino detectors. The present disclosure also relates to a method for producing such glasses and to the use of such glasses in radiation and / or particle detectors, in particular in neutron, UV or neutrino detectors. [Background technology]

[0002] Radiation and / or particle detectors often contain glass articles, such as lenses, covers, glass fibers, etc., which must not interfere with the measurement.

[0003] However, raw materials and manufacturing processes can contaminate glass with materials that interfere with certain radiation and / or particles. For example, certain components in glass contain elements that have neutron absorbing and / or UV absorbing capabilities. Some of those glass elements may even exhibit weak nuclear radiation, which can further affect the actual measurement.

[0004] For example, most conventional glasses contain Zr, Hf, and other contaminants, such as Fe, Ti, and / or Pt. Hf is radioactive at least in some isotopes and has neutron absorption capabilities. Since Zr and Hf are chemically closely related, Zr contaminants always contain Hf contaminants as well. Pt, Ti, and Fe, for example, absorb certain wavelengths of UV light. Therefore, such contaminated glasses are not particularly useful for radiation and / or particle detection devices, especially neutron detection devices, UV detectors, and neutrino detection devices.

[0005] Furthermore, since different physical mechanisms are used simultaneously in a particular detector, e.g. neutron detectors work by neutron absorption but also by scintillation which relies on the detection of UV radiation, and the detection of UV radiation is interfered with by UV absorption as well as by residual radioactivity etc., glass with contaminants will interfere on several levels with radiation and / or particle detectors making it difficult to correct for all detection errors. Summary of the Invention [Problem to be solved by the invention]

[0006] There is therefore a need in the art to provide glasses that are particularly useful for radiation and / or particle detection devices, in particular neutron detection devices, UV detectors or neutrino detection devices. [Means for solving the problem]

[0007] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In the present disclosure, Zr and Hf are essentially the same as ZrO 2 and HfO 2 Novel glass compositions and their uses are presented which are free of fluorine, fluorine, tin, tantalum, tantalum, fluorine, iodine ...

[0008] In one embodiment of the present disclosure, conventional materials used for refractory crucibles, such as zirconium aluminum silicate (AZS, known by the trade names Zirkosit® S32, S32 N, S32 KLP, S32 KLS, M36, M36 N, M36 EL, M36 KLB, M36 KLP, M36 KLS, etc.), or Al 2 O 3 Containing materials (Al 2 O 3It has been found that for glass melts containing 45-95% by weight of Korvisit® (known as Korvisit® AB, AB N, AB KLP, AB KLS, A, etc.), contamination of the glass melt with elements such as Fe, Ti, Pt, Ga, Zr (or their oxides) is unavoidable. This also results in the glass exhibiting neutron absorption, UV absorption and residual radioactivity, reducing its usefulness in radiation detection devices, especially neutron, neutrino and UV detection devices.

[0009] Neutron Detection Neutron detection is the effective detection of neutrons that enter a properly positioned detector. Currently the most common hardware for detecting neutrons is the scintillation detector. Scintillation neutron detectors include liquid organic scintillators, crystals, plastics and scintillation fibers.

[0010] Scintillation for neutron detection 6 Li-glasses were first reported in the scientific literature in 1957, and significant progress has been made since then. Scintillation glass fibers are 6 Li and Ce 3+ into the bulk composition of the glass. 6 Li 6 It has a high cross section for thermal neutron absorption through the Li(n,α) reaction. Neutron absorption produces tritium ions, alpha particles, and kinetic energy. The alpha particles and tritium interact with the glass matrix resulting in ionization, which transfers energy to Ce 3+ ions, and the excited state of Ce 3+ When the ions return to the ground state, photons with wavelengths between 390 nm and 600 nm are emitted.

[0011] The event results in a flash of light of several thousand photons for each neutron absorbed. A portion of the scintillation light propagates through a glass fiber, which acts as a waveguide. The fiber end is optically coupled to a pair of photomultiplier tubes (PMTs) to detect the burst of photons. The detector can be used to detect both neutrons and gamma rays, which are typically differentiated using pulse height discrimination. Considerable effort and progress has been made in reducing the sensitivity of fiber detectors to gamma rays. The original detectors suffered from spurious neutrons in gamma fields of 0.02 mR. Improvements in design, processes and algorithms now allow operation in gamma fields up to 20 mR / h (60Co).

[0012] Their scintillation 6 The glass used for the Li-fiber must of course contain as few contaminants as possible with elements that can absorb neutrons and thus interfere with the signal. Neutrons do not interact much with matter, but certain elements, such as hafnium (Hf), interact with neutrons by absorption and scattering. Hf exhibits efficient absorption of thermal and epithermal neutrons, with the absorption properties partially restored during prolonged exposure in the neutron flux. For example, the neutron absorption of Hf is 600 times higher than that of the closely chemically related zirconium (Zr).

[0013] Due to the lanthanide contraction, Zr and Hf exhibit similar atomic and ionic sizes. Zr-Hf have nearly identical sizes. They are called chemical twins because they have a similar number of valence electrons and similar properties. Due to this close chemical relationship, when Zr is present in a composition, Hf is also present.

[0014] However, because the glasses of the present invention contain little or no Zr (and Hf), scintillation fiber detectors made with them have excellent sensitivity and have fast timing (about 60 ns), allowing a large dynamic range in count rates. The detectors have the advantage that they can be formed into any desired shape and can be made very large or very small for use in a variety of applications. In addition, they 3 They do not rely on He, or other raw materials with limited availability, and they contain no toxic or regulated materials. Their performance is based on high pressure gaseous 3 Due to the higher density of neutron absorbing species in solid glass compared to He, the total neutron count 3 Equals or exceeds the performance of He tubes. 6 The thermal neutron cross section of Li is 3 Although it is smaller than He (940 bar vs. 5330 bar), 6 The atomic density of Li is 50 times greater, providing an advantage in the effective trapping density ratio of approximately 10:1.

[0015] Neutrino detection Well-known neutrino detectors are, on the one hand, radiochemical detectors (for example the Chlorine experiment at the Homestake gold mine in the USA, or the GALLEX detector in the Gran Sasso tunnel in Italy), and, on the other hand, detectors based on the Cherenkov effect, of which the Sudbury Neutrino Observatory (SNO) and Super-Kamiokande are the most notable. They detect solar and atmospheric neutrinos, allowing the measurement of neutrino oscillations and thus the conclusion of differences in neutrino masses, since the reactions occurring in the Sun and thus the solar neutrino emission are well known. Experiments such as the Double Shaw experiment, or the KamLAND detector at the Kamioka Neutrino Observatory (operating since 2002), can detect geoneutrinos and reactor neutrinos via inverse beta decay, providing complementary information from a range that solar neutrino detectors cannot cover.

[0016] It is clear that radioactive decay of other origins would make neutrino detection difficult or even impossible, so the materials used in neutrino detectors need to be free of such elements.

[0017] UV detection Radioactive emissions have also been found to affect the signal-to-noise ratio of UV detectors. The radioactive emissions of current UV-transmitting glasses are mostly due to the presence of radioactive isotopes of hafnium, which emit alpha and gamma radiation.

[0018] Naturally occurring hafnium consists of six isotopes: 174 Hf (0.16%), 176 Hf (5.26%), 177 Hf (18.6%), 178 Hf (27.28%), 179 Hf (13.62%), 180 Hf (35.08%). The resonance integral for the neutron capture cross section of natural hafnium in the energy range 1.0-100 keV is 1900-2300 barns. A barn (symbol: b) is a unit of 10 -28 m 2 (100fm 2 ) is a unit of area in metres. It is used in nuclear physics to express the cross section of any scattering process and is best understood as a measure of the probability of interaction between small particles. One barn is approximately the cross section of a uranium nucleus. The barn has never been an SI unit, but the SI standards body recognized it in the 8th edition of the SI pamphlet (updated in 2019) due to its use in particle physics.

[0019] Hafnium is chemically similar to zirconium and is present in many zirconium minerals. Therefore, the ZrO 2 Contamination at the 2 It is associated with contamination in the

[0020] Conventional UV-transmitting glass compositions have very high melting temperatures. Therefore, very heat-resistant refractory materials are required for the manufacture of glass. ZrO 2 It has been found that contamination in glassmaking is primarily due to the use of zirconium-containing refractory materials during the manufacture of glass, which may come into contact with the glass melt, for example as part of crucibles, melting tanks, fining tanks, and other equipment used during the manufacture of glass.

[0021] The present disclosure solves this problem by avoiding refractory materials containing zirconium during the manufacture of the glass, the resulting glass having reduced radioactive emissions.

[0022] Photomultiplier tubes and photodiodes are detectors that are typically constructed with an evacuated glass housing. Radioactive emissions from the glass result in increased background noise because the detector is sensitive not only to incident photons but also to radioactive emissions, and currents are generated by both the incident light and the incident radioactivity. Thus, radioactivity threatens the detection of the optical signal of interest by generating increased noise resulting in a worsened signal-to-noise ratio (S / N).

[0023] Thus, glasses according to this disclosure have alpha particle emissions of less than 40.1 Becquerels per gram, less than 31.6 Becquerels per gram, less than 4.42 Becquerels per gram, less than 2.21 Becquerels per gram, less than 1.106 Becquerels per gram, or less than 0.553 Becquerels per gram.

[0024] A neutrino detector may consist of a large amount of transparent material, such as water or ice, surrounded by a light-sensitive photomultiplier tube. Neutrinos can interact with atomic nuclei to produce charged leptons, which generate radiation that can be detected by the photomultiplier tube. Radioactive emissions from the glass housing of the photomultiplier tube strongly interfere with the detection of neutrinos.

[0025] Another drawback of radioactive emission from glass is that it is associated with solarization, which reduces the transmittance of the glass. Thus, radioactively emitting glass has a reduced lifetime in applications requiring high transmittance, especially high UV transmittance.

[0026] In a further aspect, the present disclosure relates to a glass having a transmission of at least 65.0% at a wavelength of 260 nm (at a nominal thickness of 1.0 mm), wherein the ZrO 2 is less than 150 ppm, or less than 140 ppm, or less than 130 ppm, or less than 120 ppm, or less than 110 ppm, or less than 50 ppm, or less than 20 ppm, or less than 10 ppm, or less than 5 ppm. Preferably, the glass is Zr-free.

[0027] In a further aspect, the present disclosure provides a method for the preparation of a glass having an Fe 2 O 3 , MoO 3 and W.O. 3 or less than 10 ppm, or less than 5 ppm, or less than 1 ppm.

[0028] In a further aspect, the present disclosure provides a method for producing a TiO 2 less than 20 ppm, or less than 15 ppm, or less than 10 ppm.

[0029] In a further embodiment, the present disclosure relates to glasses having an amount of one or more of gallium, uranium, thorium, yttrium, and thallium, and their oxides and isotopes in the glass of up to 300 ppm, up to 250 ppm, up to 200 ppm, up to 150 ppm, up to 100 ppm, up to 50 ppm, up to 25 ppm, up to 10 ppm, up to 5 ppm, up to 3 ppm, or up to 1 ppm.

[0030] UV detectors generally contain a photodiode or photomultiplier tube that converts UV light into an electric current. Often there is an additional semi-transparent protective window in front of the photodiode or it is placed in a transparent encapsulation material. In order not to degrade the performance of the UV detector, it is important that the protective window or encapsulation material has high UV transparency. For example, UV-transmitting glass can be used for this purpose due to its high UV transparency.

[0031] However, one problem that arises in this regard is that the signal-to-noise ratio (SNR or S / N) of the UV detector may be impaired, in particular due to a reduction in signal, due to an increase in noise, or due to a combination of both. It is desirable to obtain a UV detector with a particularly high S / N, especially in applications where low signals must be detected and / or where detection accuracy is particularly important. However, it is difficult to obtain a UV detector with a high S / N. For example, measures that allow an increase in the detection of the signal are often also associated with an increase in noise, and vice versa. Therefore, a UV detector with an improved S / N is desired. This is particularly true for UV detectors that include an additional semi-transparent protective window in front of the photodiode, and for UV detectors that have a photodiode that is arranged in a transparent encapsulation material.

[0032] Glass composition The glasses of the present disclosure have high UV transmittance, specifically at least 65.0% transmittance at a wavelength of 260 nm (at a nominal thickness of 1.0 mm).

[0033] Preferably, the glass of the present disclosure has a transmittance at a wavelength of 260 nm of at least 65.0%, such as at least 66.0%, at least 67.0%, at least 68.0%, at least 69.0%, at least 70.0%, more preferably at least 71.0%, more preferably at least 72.0%, more preferably at least 73.0%, more preferably at least 74.0%, more preferably at least 75.0%, more preferably at least 76.0%, more preferably at least 77.0%, more preferably at least 78.0%, more preferably at least 79.0%, or more preferably at least 80.0%. The transmittance values ​​in this disclosure relate to a nominal thickness of the glass of 1.0 mm, unless otherwise stated. This does not mean that the glass necessarily must have a thickness of 1.0 mm. Rather, the nominal thickness simply indicates what the transmittance would be if the glass had a thickness of 1.0 mm. The transmittance at a certain nominal thickness can be determined by measuring the transmittance of a sample having a thickness of 1.0 mm. Alternatively, the transmittance at 1.0 mm thickness can be determined by measuring the transmittance at other sample thicknesses, for example 0.7 mm, and then extrapolating to determine what the transmittance will be at 1.0 mm. Generally speaking, the extrapolation of the transmittance T1 at thickness d1 to the transmittance T2 at thickness d2 can be done using the following formula: T2=((T1 / P)^(d2 / d1))×P, where P is the wavelength-dependent reflection coefficient (P=P(λ)) given in units of "%". P can be determined via the Sellmeier n-coefficient:

[0034] In embodiments of the present disclosure, the transmittance at a wavelength of 260 nm (at a nominal thickness of 1.0 mm) may be up to 99.0%, up to 97.5%, up to 95.0%, up to 94.0%, up to 93.0%, up to 92.0%, up to 91.0%, up to 90.0%, up to 89.0%, up to 88.0%, up to 87.0%, up to 86.0%, up to 85.0%, up to 84.0%, up to 83.0%, up to 82.0%. The transmittance at a wavelength of 260 nm may be in the range of, for example, 65.0% to 99.0%, 66.0% to 97.5%, 67.0% to 95.0%, 68.0% to 94.0%, 69.0% to 93.0%, 70.0% to 92.0%, 71.0% to 91.0%, 72.0% to 90.0%, 73.0% to 89.0%, 74.0% to 88.0%, 75.0% to 87.0%, 76.0% to 86.0%, 77.0% to 85.0%, 78.0% to 84.0%, 79.0% to 83.0%, or 80.0% to 82.0%.

[0035] The glasses of the present disclosure are characterized by a particularly high resistance to solarization, which can be determined by irradiating the glass with an HOK 4 lamp for 144 hours and comparing the transmittance at a wavelength of 260 nm (at a nominal thickness of 1.0 mm) before and after irradiation. The term "HOK 4 lamp" refers to the high pressure mercury lamp HOK 4 / 120 from Phillips. The emission spectrum of an HOK 4 lamp is shown in Figure 1. The main emission of the lamp is at a wavelength of 365 nm. The power density at 200-280 nm and a distance of 1 m is 850 μW / cm 2 For the 144-hour irradiation of this disclosure, the distance between the HOK 4 lamp and the sample is selected to be 7 cm.

[0036] The smaller the difference between the transmittance before and after irradiation, the higher the solarization resistance. For example, there may be one glass (before irradiation) that each has a transmittance of 80% at a wavelength of 260 nm (with a reference thickness of 1.0 mm). After 144 hours of irradiation with an HOK 4 lamp, the transmittance may be 75% for the first glass and 70% for the second glass. Thus, the difference between the transmittance at a wavelength of 260 nm (with a reference thickness of 1.0 mm) before irradiation with an HOK 4 lamp and the transmittance at a wavelength of 260 nm (with a reference thickness of 1.0 mm) after 144 hours of irradiation with an HOK 4 lamp is 5% for the first glass and 10% for the second glass. Thus, the solarization resistance of the first glass is higher than that of the second glass, because the difference between the transmittance before and after irradiation is smaller for the first glass than for the second glass. High solarization resistance is associated with low solarization and vice versa. High solarization results in high induced extinction (Ext ind Correlated with.

[0037] Induction Dimming Ext ind can be determined based on the transmittance and thickness of the glass sample before and after 144 hours of irradiation with the HOK 4 lamp using the following formula:

number

[0038] Ext ind is the induced dimming, and T 後 is the transmittance after 144 hours of irradiation with the HOK 4 lamp, and T 前 is the transmittance before 144 hours of irradiation with the HOK 4 lamp, d is the thickness of the sample, and ln is the natural logarithm. Unless otherwise stated, the thickness of the sample, d, is given in cm, so the induced dimming is given in 1 / cm. Unless otherwise stated, the transmittance before and after irradiation with the HOK 4 lamp is given for a wavelength of 260 nm. Thus, the induced dimming described in this disclosure relates to induced dimming at a wavelength of 260 nm, unless otherwise stated.

[0039] In one embodiment, the induced dimming at a wavelength of 260 nm is at most 3.5 / cm, at most 3.2 / cm, at most 3.0 / cm, at most 2.9 / cm, at most 2.8 / cm, at most 2.7 / cm, at most 2.6 / cm, at most 2.5 / cm, at most 2.4 / cm, at most 2.3 / cm, at most 2.2 / cm, at most 2.1 / cm, at most 2.0 / cm, at most 1.9 / cm, at most 1.8 / cm, at most 1.7 / cm, at most 1.6 / cm, at most 1.5 / cm, at most 1.4 / cm, or at most 1.3 / cm. The induced extinction at a wavelength of 260 nm can be, for example, at least 0.01 / cm, at least 0.02 / cm, at least 0.05 / cm, at least 0.1 / cm, at least 0.2 / cm, at least 0.3 / cm, at least 0.4 / cm, at least 0.5 / cm, at least 0.55 / cm, at least 0.6 / cm, at least 0.65 / cm, at least 0.7 / cm, at least 0.75 / cm, at least 0.8 / cm, at least 0.85 / cm, at least 0.9 / cm, at least 0.95 / cm, at least 1.0 / cm, at least 1.05 / cm, or at least 1.1 / cm. At a wavelength of 260 nm, the induced dimming is, for example, 0.01 / cm~3.5 / cm, 0.02 / cm~3.2 / cm, 0.05 / cm~3.0 / cm, 0.1 / cm~2.0 / cm, 0.2 / cm~2.8 / cm, 0.3 / cm~2.7 / cm, 0.4 / cm~2.6 / cm, 0.5 / cm~2.5 / cm, 0.55 / cm~2.4 / cm, 0.6 / cm~2.3 / cm. cm, 0.65 / cm~2.2 / cm, 0.7 / cm~2.1 / cm, 0.75 / cm~2.0 / cm, 0.8 / cm~1.9 / cm, 0.85 / cm~1.8 / cm, 0.9 / cm~1.7 / cm, 0.95 / cm~1.6 / cm, 1.0 / cm~1.5 / cm, 1.05 / cm~1.4 / cm, or 1.1 / cm~1.3 / cm.

[0040] In one embodiment, the glasses of the present disclosure are characterized by high UV transmission and low induced dimming, a combination associated with high transmission at a wavelength of 260 nm (at a nominal thickness of 1.0 mm) after 144 hours of irradiation with HOK 4 lamps. The transmittance at a wavelength of 260 nm (at a nominal thickness of 1.0 mm) after 144 hours of irradiation with an HOK 4 lamp can be, for example, at least 54.0%, at least 55.0%, more preferably at least 56.0%, more preferably at least 57.0%, more preferably at least 58.0%, more preferably at least 59.0%, more preferably at least 60.0%, more preferably at least 61.0%, more preferably at least 62.0%, more preferably at least 63.0%, more preferably at least 64.0%, more preferably at least 65.0%, more preferably at least 66.0%, more preferably at least 67.0%, more preferably at least 68.0%, more preferably at least 69.0%, more preferably at least 70.0%, more preferably at least 71.0%, more preferably at least 72.0%, more preferably at least 73.0%, or preferably at least 74.0%.

[0041] The transmittance at a wavelength of 260 nm (at a nominal thickness of 1.0 mm) after 144 hours of irradiation with an HOK 4 lamp can be, for example, up to 95.0%, up to 94.0%, up to 93.0%, up to 92.0%, up to 91.0%, up to 90.0%, up to 89.0%, up to 88.0%, up to 87.0%, up to 86.0%, up to 85.0%, up to 84.0%, up to 83.0%, up to 82.0%, up to 81.0%, up to 80.0%, up to 79.0%, up to 78.0%, up to 77.0%, up to 76.0%, or up to 75.0%. The transmittance at a wavelength of 260 nm is, for example, 54.0% to 95.0%, 55.0% to 94.0%, 56.0% to 93.0%, 57.0% to 92.0%, 58.0% to 91.0%, 59.0% to 90.0%, 60.0% to 89.0%, 61.0% to 88.0%, 62.0% to 87.0%, 63.0% to 86.0%, 64.0% It can be in the range of 0.0 to 85.0%, 65.0% to 84.0%, 66.0% to 83.0%, 67.0% to 82.0%, 68.0% to 81.0%, 69.0% to 80.0%, 70.0% to 79.0%, 71.0% to 78.0%, 72.0% to 77.0%, 73.0% to 76.0%, or 74.0% to 75.0%.

[0042] In one embodiment, the present disclosure relates to a glass comprising the following components: [Table 1]

[0043] In one embodiment, F is added to the total mass of the glass composition. - may be present in the glass in an amount of 0 to 3% by weight, and / or Cl - can be present in the glass at 0-1 wt.%. At least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, or up to 100 wt.% of the anions can be oxygen. Oxygen is present as the oxide of the respective cation, i.e., R 2 O or RO, e.g., SiO 2 , Al 2 O 3 , B 2 O 3 , Li2 O, Na 2 OK 2 It can exist in the form of O, MgO, CaO, SrO, BaO, etc.

[0044] "Cation %" describes the "cation percent" in terms of the relative molar proportion of cations to the total amount of cations in the glass, which of course also contains anions.

[0045] "R + " describes the sum of all cations of all alkali metals in the glass. 2+ " describes the sum of all cations of all alkaline earth metals in the glass.

[0046] The glass of the present disclosure is Si 4+ In the present invention, the cationic cation content is at least 52%. 4+ Contributes to the hydrolytic resistance and permeability of the glass. 4+ If the content is too high, the melting point of the glass is too high. 4 and T g For this reason, Si 4+ The Si content should be limited to 71% cations or less. 4+ is preferably at least 52 cation %, at least 53 cation %, or at least 54 cation %. In embodiments, the content may be limited to no more than 70 cation %, no more than 69 cation %, or no more than 68 cation %.

[0047] The glass of the present disclosure is Al 3+ Contains less than 8% cations. Higher percentage of Al 3+ In addition, Al reduces the acid resistance. 3+ are the melting point and T 4 Therefore, the content of this component can be limited to a maximum of 7 cationic %, or to a maximum of 6 cationic %. In an advantageous embodiment, Al 3+is used in a minor proportion of at least 0.25 cationic %, at least 0.5 cationic %, at least 0.75 cationic %, at least 1.15 cationic %, at least 1.25 cationic %, at least 1.5 cationic %, or at least 1.75 cationic %, or at least 2.0 cationic %.

[0048] The glass of the present disclosure is B 3+ In the present invention, the cationic polymer may contain at least 1.0% cationic polymer. 3+ has a beneficial effect on the melting properties of the glass, in particular the melting point is lowered and the glass can be fused to other materials at low temperatures. Too much B 3+ has a detrimental effect on hydrolytic resistance and tends to result in high evaporative losses of the glass during manufacture, leading to clumpy glasses. It may be limited to 35 cation %, 32 cation %, or 31.5 cation %. In certain embodiments, B 3+ The content of is 30.5 cation % or less. 3+ can be at least 1.15 cationic %, at least 1.25 cationic %, at least 1.5 cationic %, at least 2.0 cationic %, at least 2.25 cationic %, at least 2.5 cationic %, at least 2.75 cationic %, or at least 2.8 cationic %.

[0049] The glass of the present disclosure is Li + Li may contain up to 8 cation %, up to 7 cation %, or up to 6.5 cation %. + Lithium oxide increases the fusibility of the glass and advantageously shifts the UV edge to shorter wavelengths. However, lithium oxide has a tendency to evaporate and also increases the cost of the mixture. In a preferred embodiment, the glass contains little Li + % or less, e.g., 0.5 cation % or less, 0.25 cation % or less, or 0.15 cation % or less, or the glass contains Li + In a preferred embodiment, the glass contains 0.01 to 8 cationic %, 0.025 to 7 cationic %, or 0.05 to 6.5 cationic % Li. + Contains:

[0050] The glass of the present disclosure is Na + Contains up to 17% cations. + Sodium oxide increases the fusibility of the glass. However, sodium oxide also leads to a decrease in UV transmittance and an increase in the thermal expansion coefficient. + In one embodiment, Na + is greater than 2.0 cation %, or greater than 3.0 cation %.

[0051] The glass of the present disclosure is K + Contains 14% or less of cations. + It increases the melting point of the glass and favorably shifts the UV edge to shorter wavelengths. Its percentage can be at least 0.5 cationic %, or at least 0.75 cationic %. However, an excessively high potassium oxide content can lead to the isotope 40 The radioactive properties of K lead to glasses that are not suitable for use in photomultiplier tubes. For this reason, the content of this element should be limited to less than 13 cation %, or even less than 12 cation %. + In one embodiment, the cationic cation may comprise at least 0.5 cationic %, or at least 0.75 cationic %. + The content is 0.5 cationic % to 14 cationic %, or 0.75 cationic % to 13 cationic %.

[0052] The glass of the present disclosure is Mg 2+ may contain up to 2 cationic % or up to 1 cationic %. 2+ is advantageous for fusibility, but at high percentages it has been found to be problematic with respect to the desired UV transmission. 2+ Not included.

[0053] The glass of the present disclosure is Ca 2+ Ca may be present in amounts up to 2% or up to 1%. 2+is advantageous for fusibility, but at high percentages it has been found to be problematic with respect to the desired UV transmittance. 2+ Not included.

[0054] The glass of the present disclosure is Sr 2+ up to 2 cationic %, up to 1 cationic %, or up to 0.5 cationic %. 2+ is advantageous for fusibility, but at high percentages it has been found to be problematic with respect to the desired UV transmittance. 2+ No or only small amounts of Sr 2+ , e.g., at least 0.01 cationic %, at least 0.025 cationic %, at least 0.05 cationic %, or at least 0.1 cationic %. A preferred embodiment is Sr 2+ Not included.

[0055] The glass of the present disclosure is Ba 2+ up to 4 cation %, or up to 3 cation %. 2+ leads to an improvement in hydrolytic resistance. However, an excessively high barium oxide content leads to glass instability. A preferred embodiment contains no more than Ba 2+ at least 0.01 cationic %, at least 0.05 cationic %, or at least 0.1 cationic %.

[0056] The glasses of the present disclosure are - The glass composition may contain F in an amount of 0 to 3 mass % based on the total mass of the glass composition. - The content of component F is preferably 2% by weight or less. In one embodiment, at least 0.1% by weight, or at least 0.3% by weight of this component is used. - improves the fusibility of the glass and influences the UV edge in the direction of shorter wavelengths.

[0057] The glasses of the present disclosure are -in an amount of less than 1% by weight, in particular less than 0.5% by weight, or less than 0.4% by weight, relative to the total weight of the glass composition. A suitable lower limit is 0.01% or 0.05% by weight.

[0058] In a preferred embodiment, B 3+ , R 2+ and R + The total content (cation %) of Si 4+ and Al 3+ The ratio of the total content (cation %) of is not more than 0.8, in particular not more than 0.75, or more preferably not more than 0.73. In one embodiment, this value is at least 0.1, preferably at least 0.2, or at least 0.3. Glasses having the specified percentage ratios show good properties in terms of hydrolytic resistance and have low induced dimming, which has many advantages, especially when used as UV-transmitting materials.

[0059] In one embodiment of the present disclosure, the cationic % Na + Content of K + The ratio of Na to the content of is at least 0.5, in particular at least 0.75. In one embodiment, the specified ratio is equal to or less than 4, in particular equal to or less than 3. Both oxides serve to improve the melting properties of the glass. However, too much Na + If too much K is used, UV transmittance will decrease. + increases the coefficient of thermal expansion. It has been found that the indicated ratios achieve the best results, i.e., the UV transmittance and the coefficient of thermal expansion are in the advantageous range.

[0060] R in the glasses of the present disclosure 2+ The sum of R is preferably 30 cation % or less, 29 cation % or less, or 27 cation % or less. The glass has an R of at least 6.5 cation %, at least 7.5 cation %, or at least 8 cation %. 2+ The alkali metal oxides increase the fusibility of the glass, but as mentioned above, in high proportions they lead to a number of drawbacks.

[0061] Alkaline Earth Oxide R + It has been found that Ba has a significant effect on hydrolysis resistance. Therefore, in one embodiment, special attention is paid to the contents of these components and their ratio to each other. Therefore, Ba in cation % 2+ of Mg in cations 2+ and Sr 2+ and Ca 2+ The ratio of the content of Ba to the total content of Ba should be at least 0.5. This value is preferably at least 0.6, and more preferably at least 0.7. 2+ provides the greatest advantage in terms of hydrolysis resistance over other alkaline earth metal oxides. Nevertheless, the specified ratio should not exceed a value of 2 or 1. In an advantageous embodiment, the glass contains at least a small amount of Ba. 2+ and Mg 2+ and / or Sr 2+ and / or Ca 2+ Not included.

[0062] The advantageous properties are in particular due to the Ca content in the glass at each cation percentage. 2+ Ba 2+ This is obtained when the ratio of the proportion to is less than 3.0. In particular, this ratio should be less than 2.5, or even less than 2. The optimal ratio is even lower, in particular less than 1.75, or even less than 1.5. In a preferred embodiment, this value is 0.

[0063] In one embodiment, the glass has a cation percentage of B 3+ Ba 2+ to at least 0.5 and not more than 85. Said ratio is preferably at least 1, or at least 1.1. In preferred embodiments, the specified ratio is limited to not more than 84, not more than 83, not more than 82, or not more than 81. In particular, said ratio is at least 1.2 and not more than 81. Glasses having the specified ratios of percentages exhibit good properties with regard to hydrolytic resistance and only small induced dimming.

[0064] R in the glasses of the present disclosure +The sum of may be at least 0.5 cationic %, or at least 0.7 cationic %. Alkaline earth metal oxides are advantageous for fusibility, but large proportions have been found to be problematic with respect to the desired UV transmittance. In one embodiment, the glass has an R of 4 cationic % or less, or 3 cationic % or less, or 2.5 cationic % or less. + Contains:

[0065] Sum of the cation content of alkaline earth metal oxides and alkali metal oxides in % R + +R 2+ may be limited to 30 cation % or less. Advantageous embodiments may contain these components in amounts of 29 cation % or less. The oxide content is preferably at least 2 cation %, at least 2.5 cation %, or at least 3 cation %. Excessively increased proportions of these components reduce the hydrolytic resistance of the glass.

[0066] B 3+ The cation content in %, R 2+ and R + The ratio of the content in % of cations of B to the sum can be at least 0.04, at least 0.05, or at least 0.068. The ratio can be limited to a maximum of 9, a maximum of 8.5, or a maximum of 8. The alkali metal borate or alkaline earth metal borate can be a salt of B 3+ It has been found to be advantageous to set the indicated ratio.

[0067] T g and T 4 B so that the solubility characteristics, including 3+ The content of Si 4+ and Al 3+ It can be advantageous to set the ratio of the content in % of cations of to the sum within a narrow range. In an advantageous embodiment, this ratio is at least 0.03 and / or not more than 0.5.

[0068] Alkali Metal Oxide R 2+ The total of alkaline earth metal oxides R + The ratio of the proportion in % of cations to the sum of is preferably at least 4.4, in particular at least 5.45, or at least 6.0. In an embodiment, this ratio is 14 or less, 13 or less, or 12 or less.

[0069] In one embodiment of the present disclosure, a glass is provided comprising the following components: [Table 2]

[0070] In one embodiment, F is added to the total mass of the glass composition. - may be present in the glass in an amount of 0 to 2% by weight, and / or Cl - can be present in the glass at 0-1 wt.%. At least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, or up to 100 wt.% of the anions can be oxygen. Oxygen is present as the oxide of the respective cation, i.e., R 2 O or RO, e.g., SiO 2 , Al 2 O 3 , B 2 O 3 , Li 2 O, Na 2 OK 2 It can exist in the form of O, MgO, CaO, SrO, BaO, etc.

[0071] In one embodiment, the glass of the present disclosure comprises Si 4+ In one embodiment, the Si 4+ The Si content should be limited to 73 cation % or less. 4+ is preferably at least 60 cationic %, at least 61 cationic %, or at least 62 cationic %. In embodiments, the content may be limited to no more than 72 cationic %, no more than 71 cationic %, or no more than 70 cationic %.

[0072] In one embodiment, the glass of the present disclosure comprises Al 3+ in a proportion of 3 cationic % or less. The content of this component may be limited to a maximum of 3 cationic %, or to a maximum of 2.5 cationic %. In an advantageous embodiment, Al 3+ is used in a minor proportion of at least 0.25 cationic %, at least 0.5 cationic %, at least 1.0 cationic %, or at least 1.5 cationic %.

[0073] In one embodiment, the glass of the present disclosure is B 3+ In certain embodiments, B may contain at least 1.0 cationic %. It may be limited to 5 cationic %, to 4.5 cationic %, or to 4 cationic %. 3+ The content of is 3.5 cation % or less. 3+ can be at least 1.5 cationic %, or at least 2.0 cationic %.

[0074] In one embodiment, the glasses of the present disclosure contain Li + In a preferred embodiment, the glass contains up to 1 cation %, up to 0.5 cation %, or up to 0.25 cation % of Li. + Not included.

[0075] In one embodiment, the glass of the present disclosure comprises Na + The glass contains up to 17% Na + In one embodiment, the cationic cations may include at least 12% or at least 13%. + The content is 12 cationic % to 17 cationic %, or 13 cationic % to 15 cationic %.

[0076] In one embodiment, the glasses of the present disclosure are +The proportion may be at least 10.5 cationic %, or at least 11.75 cationic %. However, an excessively high potassium oxide content may lead to the isotope 40 The radioactive properties of K lead to glasses that are not suitable for use in photomultiplier tubes. For this reason, the content of this element must be limited to less than 14 cation %, or even less than 13 cation %. + In one embodiment, the cationic cation may comprise at least 10.5 cationic %, or at least 11.25 cationic %. + The content is 10.5 cationic % to 14 cationic %, or 11.25 cationic % to 13 cationic %.

[0077] In one embodiment of the present disclosure, the glass of the present disclosure comprises Mg 2+ In a preferred embodiment, the alloy may contain up to 1 cationic % of Mg. 2+ Not included.

[0078] In one embodiment of the present disclosure, the glass of the present disclosure comprises Ca 2+ In a preferred embodiment, the calcium phosphate ... 2+ Not included.

[0079] In one embodiment of the present disclosure, the glass contains Sr 2+ In a preferred embodiment, the alloy may contain up to 1 cationic %, up to 0.5 cationic %, or up to 0.25 cationic % of Sr 2+ No or only small amounts of Sr 2+ , e.g., at least 0.015 cationic %, at least 0.025 cationic %, or at least 0.01 cationic %. A preferred embodiment contains Sr 2+ Not included.

[0080] In one embodiment of the present disclosure, the glass of the present disclosure is Ba 2+In a preferred embodiment, the cations may contain up to 4% or up to 3%. 2+ in a proportion of at least 0.5 cationic %, at least 1 cationic %, or at least 1.5 cationic %.

[0081] The glasses of the present disclosure are - The glass composition may contain F in an amount of 0 to 1 mass % based on the total mass of the glass composition. - The content of component F is preferably 0.8% by weight or less. In one embodiment, at least 0.1% by weight, or at least 0.3% by weight, of this component is used. - improves the fusibility of the glass and influences the UV edge in the direction of shorter wavelengths.

[0082] The glasses of the present disclosure are - in an amount of less than 1% by weight, in particular less than 0.5% by weight, or less than 0.4% by weight, relative to the total weight of the glass composition. A suitable lower limit is 0.01% or 0.05% by weight.

[0083] In one embodiment, B 3+ , R 2+ and R + The total content (cation %) of Si 4+ and Al 3+ to the sum (cation %) is less than or equal to 0.51, in particular less than or equal to 0.48, or more preferably less than or equal to 0.47. In one embodiment, this value is at least 0.2, preferably at least 0.3, or at least 0.4.

[0084] In one embodiment of the present disclosure, the cationic % Na + Content of K + is at least 0.5, in particular at least 0.75. In one embodiment, the specified ratio is less than or equal to 3, in particular less than or equal to 2. It has been found that the indicated ratio achieves the best results, i.e. the UV transmittance and the thermal expansion coefficient are in the advantageous range.

[0085] In one embodiment of the present disclosure, the R 2+ is preferably 30 cation % or less, 29 cation % or less, or 27 cation % or less. 2+ in a proportion of at least 18.5 cationic %, at least 19.5 cationic %, or at least 20 cationic %.

[0086] In one embodiment, the glass contains at least a small amount of Ba. 2+ Contains Ca 2+ and / or Mg 2+ and / or Sr 2+ Not included.

[0087] In one embodiment, the glass has a cation percentage of B 3+ Ba 2+ to at least 0.25 and not more than 3. Said ratio is preferably at least 0.5, or at least 0.75. In preferred embodiments, the specified ratio is limited to not more than 2.5, not more than 2, not more than 1.75, or not more than 1.5. In particular, said ratio is at least 1.1 and not more than 1.35.

[0088] In one embodiment, R in the glass of the present disclosure + can be at least 1 cation %, or at least 2 cation %. In one embodiment, the glass has an R of 5 cation % or less, or 4 cation % or less, or 3 cation % or less. + Contains:

[0089] In one embodiment, the sum of the contents of the alkaline earth metal oxide and the alkali metal oxide in cation % R + +R 2+ may be limited to 35 cation % or less. Advantageous embodiments may contain these components in amounts of 32 cation % or less. The oxide content is preferably at least 25 cation %, at least 26 cation %, or at least 27 cation %.

[0090] In one embodiment, B 3+ The cation content in %, R 2+ and R + to the sum of their contents in % of cations can be at least 0.04, at least 0.05, or at least 0.068. Said ratio can be limited to a maximum of 1.5, a maximum of 1.0, or a maximum of 0.5. It has been found to be advantageous to set the indicated ratios.

[0091] In one embodiment, B 3+ The content of Si 4+ and Al 3+ to the sum of their contents in cation % is at least 0.01 and / or not more than 0.1, or at least 0.03 and / or not more than 0.08.

[0092] In one embodiment, the alkali metal oxide R 2+ The total of alkaline earth metal oxides R + The ratio of the proportion in % of cations to the sum of is preferably at least 9, in particular at least 10, or at least 11. In an embodiment, this ratio is 14 or less, 13 or less, or 12 or less.

[0093] In one embodiment of the present disclosure, a glass is provided comprising the following components: [Table 3]

[0094] In one embodiment, F is added to the total mass of the glass composition. - may be present in the glass in an amount of 0 to 1% by weight, and / or Cl - can be present in the glass at 0-1 wt.%. At least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, or up to 100 wt.% of the anions can be oxygen. Oxygen is present as the oxide of the respective cation, i.e., R 2 O or RO, e.g., SiO 2 , Al 2O 3 , B 2 O 3 , Li 2 O, Na 2 OK 2 It can exist in the form of O, MgO, CaO, SrO, BaO, etc.

[0095] In one embodiment of the present disclosure, a glass is provided comprising the following components: [Table 4]

[0096] In one embodiment, F is added to the total mass of the glass composition. - may be present in the glass in an amount of 0 to 2% by weight, and / or Cl - can be present in the glass at 0-1 wt.%. At least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, or up to 100 wt.% of the anions can be oxygen. Oxygen is present as the oxide of the respective cation, i.e., R 2 O or RO, e.g., SiO 2 , Al 2 O 3 , B 2 O 3 , Li 2 O, Na 2 OK 2 It can exist in the form of O, MgO, CaO, SrO, BaO, etc.

[0097] In one embodiment, the glass of the present disclosure comprises Si 4+ In the present invention, the cationic cation content is at least 52%. 4+ The content of Si must be limited to 65 cation % or less. 4+ is preferably at least 52 cationic %, at least 53 cationic %, or at least 54 cationic %. In embodiments, the content may be limited to no more than 65 cationic %, no more than 64 cationic %, or no more than 63 cationic %.

[0098] In one embodiment, the glass of the present disclosure comprises Al 3+ in a proportion of 8 cationic % or less. The content of this component can therefore be limited to a maximum of 7.5 cationic %, or even to a maximum of 7 cationic %. In an advantageous embodiment, Al 3+ is used in a minor proportion of at least 1.5 cationic %, at least 2 cationic %, at least 2.5 cationic %, or at least 3.0 cationic %.

[0099] In one embodiment, the glass of the present disclosure is B 3+ In certain embodiments, B may contain at least 18.0 cation %. It may be limited to up to 32 cation %, up to 32.5 cation %, or up to 31.5 cation %. 3+ The content of is 31 cation % or less. 3+ can be at least 18.5 cation %, or at least 19.0 cation %.

[0100] In one embodiment, the glasses of the present disclosure contain Li + In a preferred embodiment, the glass contains a minor proportion of Li. + %, for example at least 0.15 cationic %, at least 1.25 cationic %, or at least 1.45 cationic %. In preferred embodiments, the glass contains 0.25 to 4 cationic %, 1.75 to 3.25 cationic %, or 2.0 to 2.95 cationic % Li. + Contains:

[0101] In one embodiment, the glass of the present disclosure comprises Na + The glass contains up to 6 cation % of Na + In one embodiment, the cationic cation may contain at least 2% Na. + The content is 2 cationic % to 6 cationic %, or 3 cationic % to 5 cationic %.

[0102] In one embodiment, the glasses of the present disclosure are + The proportion may be at least 0.25 cationic %, or at least 0.5 cationic %. However, an excessively high potassium oxide content may lead to the isotope 40 The radioactive properties of K lead to glasses that are not suitable for use in photomultiplier tubes. For this reason, the content of this element should be limited to less than 2 cation %, or even less than 1.5 cation %. The glasses are + In one embodiment, the cationic cation may comprise at least 0.5 cationic %, or at least 0.75 cationic %. + The content is 0.5 cationic % to 3 cationic %, or 0.75 cationic % to 2 cationic %.

[0103] In one embodiment of the present disclosure, the glass of the present disclosure comprises Mg 2+ In a preferred embodiment, the alloy may contain up to 2 cationic % or up to 1 cationic % of Mg. 2+ Not included.

[0104] In one embodiment of the present disclosure, the glass of the present disclosure comprises Ca 2+ In a preferred embodiment, the calcium phosphate ... 2+ Not included.

[0105] In one embodiment of the present disclosure, the glass contains Sr 2+ In a preferred embodiment, the cations are Sr 2+ No or only small amounts of Sr 2+ , e.g., at least 0.025 cationic %, at least 0.05 cationic %, or at least 0.1 cationic %. A preferred embodiment is Sr 2+ Not included.

[0106] In one embodiment of the present disclosure, the glass of the present disclosure is Ba 2+In a preferred embodiment, the cations may contain up to 2% or up to 1% of Ba. 2+ in a proportion of at least 0.05 cationic %, at least 0.1 cationic %, or at least 0.2 cationic %.

[0107] The glasses of the present disclosure are - The glass composition may contain F in an amount of 0 to 2 mass % based on the total mass of the glass composition. - The content of component F is preferably 1% by weight or less. In one embodiment, at least 0.1% by weight, or at least 0.3% by weight of this component is used. - improves the fusibility of the glass and influences the UV edge in the direction of shorter wavelengths.

[0108] The glasses of the present disclosure are - in an amount of less than 1% by weight, in particular less than 0.5% by weight, or less than 0.4% by weight, relative to the total weight of the glass composition. A suitable lower limit is 0.01% or 0.05% by weight.

[0109] In one embodiment, B 3+ , R 2+ and R + The total content (cation %) of Si 4+ and Al 3+ to the sum (cation %) is less than or equal to 0.8, in particular less than or equal to 0.75, or more preferably less than or equal to 0.7. In one embodiment, this value is at least 0.4, preferably at least 0.45, or at least 0.5.

[0110] In one embodiment of the present disclosure, the cationic % Na + Content of K + The ratio of to the content is at least 1, in particular at least 2. In one embodiment, the specified ratio is equal to or less than 4, in particular equal to or less than 3. It has been found that the indicated ratio achieves the best results, i.e. the UV transmittance and the thermal expansion coefficient are in the advantageous range.

[0111] In one embodiment of the present disclosure, the R 2+ The sum of is preferably 11 cation % or less, 10 cation % or less, or 9 cation % or less. 2+ in a proportion of at least 7 cationic %, at least 7.5 cationic %, or at least 8 cationic %.

[0112] In one embodiment, the cationic % of Ba 2+ of Mg in cations 2+ and Sr 2+ and Ca 2+ The ratio of the total content of Ca and CaO to the total content of Ca should be at least 0.5. This value is preferably at least 0.6, at least 0.7. Nevertheless, the specified ratio should not exceed a value of 3 or 2.5. In an advantageous embodiment, the glass contains at least a small amount of Ca 2+ and / or Ba 2+ and Mg 2+ and / or Sr 2+ Not included.

[0113] In one embodiment, the ratio of CaO / BaO is at least 0.25, at least 0.35, and not more than 2.0, or not more than 1.5.

[0114] In one embodiment, the glass has a cation percentage of B 3+ Ba 2+ to at least 20 and not more than 100. Said ratio is preferably at least 21 and not more than 90. In preferred embodiments, the specified ratio is limited to not more than 85, not more than 83, or not more than 82. In particular, said ratio is at least 23 and not more than 81.5.

[0115] In one embodiment, R in the glass of the present disclosure + can be at least 0.5 cation %, or at least 0.6 cation %. In one embodiment, the glass has an R of 3 cation % or less, or 2 cation % or less, or 1.5 cation % or less. + Contains:

[0116] In one embodiment, the sum of the contents of the alkaline earth metal oxide and the alkali metal oxide in cation % R + +R 2+ may be limited to 12 cation % or less. Advantageous embodiments may contain these components in amounts of 11 cation % or less. The oxide content is preferably at least 6 cation %, at least 7 cation %, or at least 8 cation %.

[0117] In one embodiment, B 3+ The cation content in %, R 2+ and R + to the sum of their contents in % of cations can be at least 0.5, at least 1.0, or at least 1.5. Said ratio can be limited to a maximum of 5, a maximum of 4.5, or a maximum of 4. It has been found to be advantageous to set the indicated ratios.

[0118] In one embodiment, B 3+ The content of Si 4+ and Al 3+ to the sum of their contents in cation % is at least 0.2 and / or not more than 0.8, or at least 0.3 and / or not more than 0.6.

[0119] In one embodiment, the alkali metal oxide R 2+ The total of alkaline earth metal oxides R + The ratio of the proportion in % of cations to the sum of is preferably at least 5, in particular at least 5.5, or at least 6. In an embodiment, this ratio is 11 or less, 10.5 or less, or 10 or less.

[0120] In one embodiment of the present disclosure, a glass is provided comprising the following components: [Table 5]

[0121] In one embodiment, F is added to the total mass of the glass composition. - may be present in the glass in an amount of 0 to 2% by weight, and / or Cl - can be present in the glass at 0-1 wt.%. At least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, or up to 100 wt.% of the anions can be oxygen. Oxygen is present as the oxide of the respective cation, i.e., R 2 O or RO, e.g., SiO 2 , Al 2 O 3 , B 2 O 3 , Li 2 O, Na 2 OK 2 It can exist in the form of O, MgO, CaO, SrO, BaO, etc.

[0122] In yet another embodiment of the present disclosure, a glass is provided comprising the following components: [Table 6]

[0123] In one embodiment, F is added to the total mass of the glass composition. - may be present in the glass in an amount of 0 to 2% by weight, and / or Cl - can be present in the glass at 0-1 wt.%. At least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, or up to 100 wt.% of the anions can be oxygen. Oxygen is present as the oxide of the respective cation, i.e., R 2 O or RO, e.g., SiO 2 , Al 2 O 3 , B 2 O 3 , Li 2 O, Na 2 OK 2 It can exist in the form of O, MgO, CaO, SrO, BaO, etc.

[0124] In one embodiment, the glass of the present disclosure comprises Si 4+ In the present invention, the cationic cation content is at least 56%. 4+ The content of Si must be limited to 62 cation % or less. 4+ is preferably at least 57 cationic %, at least 57.5 cationic %, or at least 58 cationic %. In embodiments, the content may be limited to no more than 61 cationic %, no more than 60 cationic %, or no more than 59.8 cationic %.

[0125] In one embodiment, the glass of the present disclosure comprises Al 3+ in a proportion of 8 cationic % or less. The content of this component can therefore be limited to a maximum of 7.5 cationic %, or even to a maximum of 7 cationic %. In an advantageous embodiment, Al 3+ is used in a minor proportion of at least 4.5 cationic %, at least 5 cationic %, at least 5.5 cationic %, or at least 6.0 cationic %.

[0126] In one embodiment, the glass of the present disclosure is B 3+ In certain embodiments, B may contain at least 18.0 cation %. It may be limited to up to 28 cation %, up to 27.5 cation %, or up to 26.5 cation %. 3+ The content of is 26% or less of cations. 3+ can be at least 20.5 cation %, or at least 22.0 cation %.

[0127] In one embodiment, the glasses of the present disclosure contain Li + In a preferred embodiment, the glass contains a minor proportion of Li. + %, for example at least 0.15 cationic %, at least 1.25 cationic %, or at least 1.45 cationic %. In preferred embodiments, the glass contains 0.25 to 4 cationic %, 1.75 to 3.25 cationic %, or 2.0 to 2.95 cationic % Li. +Contains:

[0128] In one embodiment, the glass of the present disclosure comprises Na + The glass contains up to 6 cation % of Na + In one embodiment, the cationic cation may contain at least 2% Na. + The content is 2 cationic % to 6 cationic %, or 3 cationic % to 5 cationic %.

[0129] In one embodiment, the glasses of the present disclosure are + The proportion may be at least 0.25 cationic %, or at least 0.5 cationic %. However, an excessively high potassium oxide content may lead to the isotope 40 The radioactive properties of K lead to glasses that are not suitable for use in photomultiplier tubes. For this reason, the content of this element should be limited to less than 2 cation %, or even less than 1.5 cation %. The glasses are + In one embodiment, the cationic cation may comprise at least 0.5 cationic %, or at least 0.75 cationic %. + The content is 0.5 cationic % to 3 cationic %, or 0.75 cationic % to 2 cationic %.

[0130] In one embodiment of the present disclosure, the glass of the present disclosure comprises Mg 2+ In a preferred embodiment, the alloy may contain up to 2 cationic % or up to 1 cationic % of Mg. 2+ Not included.

[0131] In one embodiment of the present disclosure, the glass of the present disclosure comprises Ca 2+ In a preferred embodiment, the calcium phosphate ... 2+ Not included.

[0132] In one embodiment of the present disclosure, the glass contains Sr 2+In a preferred embodiment, the alloy may contain up to 1 cationic %, up to 0.75 cationic %, or up to 0.5 cationic % of Sr 2+ No or only small amounts of Sr 2+ , e.g., at least 0.025 cationic %, at least 0.05 cationic %, or at least 0.1 cationic %. A preferred embodiment is Sr 2+ Not included.

[0133] In one embodiment of the present disclosure, the glass of the present disclosure is Ba 2+ In a preferred embodiment, the cations may contain up to 2% or up to 1% of Ba. 2+ in a proportion of at least 0.05 cationic %, at least 0.1 cationic %, or at least 0.2 cationic %.

[0134] The glasses of the present disclosure are - The glass composition may contain F in an amount of 0 to 2 mass % based on the total mass of the glass composition. - The content of component F is preferably 1% by weight or less. In one embodiment, at least 0.1% by weight, or at least 0.3% by weight of this component is used. - improves the fusibility of the glass and influences the UV edge in the direction of shorter wavelengths.

[0135] The glasses of the present disclosure are - in an amount of less than 1% by weight, in particular less than 0.5% by weight, or less than 0.4% by weight, relative to the total weight of the glass composition. A suitable lower limit is 0.01% or 0.05% by weight.

[0136] In one embodiment, B 3+ , R 2+ and R + The total content (cation %) of Si 4+ and Al 3+ to the sum (cation %) is less than or equal to 0.6, in particular less than or equal to 0.55, or more preferably less than or equal to 0.54. In one embodiment, this value is at least 0.4, preferably at least 0.45, or at least 0.5.

[0137] In one embodiment of the present disclosure, the cationic % Na + Content of K + The ratio of to the content is at least 1, in particular at least 2. In one embodiment, the specified ratio is equal to or less than 4, in particular equal to or less than 3. It has been found that the indicated ratio achieves the best results, i.e. the UV transmittance and the thermal expansion coefficient are in the advantageous range.

[0138] In one embodiment of the present disclosure, the R 2+ The sum of is preferably 11 cation % or less, 10 cation % or less, or 9 cation % or less. 2+ in a proportion of at least 7 cationic %, at least 7.5 cationic %, or at least 8 cationic %.

[0139] In one embodiment, the cationic % of Ba 2+ of Mg in cations 2+ and Sr 2+ and Ca 2+ The ratio of the total content of Ca and CaO to the total content of Ca should be at least 1. This value is preferably at least 1.5, at least 2.0. Nevertheless, the specified ratio should not exceed a value of 3, or 2.5. In an advantageous embodiment, the glass contains at least a small amount of Ca 2+ and / or Ba 2+ and Mg 2+ and / or Sr 2+ Not included.

[0140] In one embodiment, the ratio of CaO / BaO is at least 0.25, at least 0.35, and not more than 1.0, or not more than 0.75.

[0141] In one embodiment, the glass has a cation percentage of B 3+ Ba 2+to is at least 20 and not more than 30. Said ratio is preferably at least 21 and not more than 28. In preferred embodiments, the specified ratio is limited to not more than 27, not more than 26, not more than 25. In particular, said ratio is at least 22 and not more than 24.5.

[0142] In one embodiment, R in the glass of the present disclosure + can be at least 1 cation %, or at least 1.25 cation %. In one embodiment, the glass has an R of 3 cation % or less, or 2 cation % or less, or 1.5 cation % or less. + Contains:

[0143] In one embodiment, the sum of the contents of the alkaline earth metal oxide and the alkali metal oxide in cation % R + +R 2+ may be limited to 12 cation % or less. Advantageous embodiments may contain these components in amounts of 11 cation % or less. The oxide content is preferably at least 9 cation %, at least 9.5 cation %, or at least 10 cation %.

[0144] In one embodiment, B 3+ The cation content in %, R 2+ and R + to the sum of their contents in % of cations can be at least 0.5, at least 1.0, or at least 1.5. Said ratio can be limited to a maximum of 3.5, a maximum of 3, or a maximum of 2.5. It has been found to be advantageous to set the indicated ratios.

[0145] In one embodiment, B 3+ The content of Si 4+ and Al 3+ The ratio of the content in % of cations to the sum is at least 0.2 and / or not more than 0.8, or at least 0.3 and / or not more than 0.6.

[0146] In one embodiment, the alkali metal oxide R2+ The total of alkaline earth metal oxides R + The ratio of the proportion in % of cations to the sum of is preferably at least 5, in particular at least 5.5, or at least 6. In an embodiment, this ratio is 9 or less, 8.5 or less, or 7 or less.

[0147] In one embodiment of the present disclosure, a glass is provided comprising the following components: [Table 7]

[0148] In one embodiment, F is added to the total mass of the glass composition. - may be present in the glass in an amount of 0 to 1% by weight, and / or Cl - can be present in the glass at 0-1 wt.%. At least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, or up to 100 wt.% of the anions can be oxygen. Oxygen is present as the oxide of the respective cation, i.e., R 2 O or RO, e.g., SiO 2 , Al 2 O 3 , B 2 O 3 , Li 2 O, Na 2 OK 2 It can exist in the form of O, MgO, CaO, SrO, BaO, etc.

[0149] In this specification, "ppm" is a mass percentage.

[0150] When it is stated herein that a glass is free of an ingredient or does not contain a particular ingredient, this means that this ingredient may be present at most as an impurity. This means that it is not added in a significant amount. According to the present disclosure, "insignificant amount" means an amount less than 500 ppm, preferably less than 250 ppm, and most preferably less than 50 ppm, unless otherwise stated for the relevant ingredient.

[0151] In further embodiments, according to the present disclosure, "insignificant amounts of trace elements" refers to any element or element present at less than 10 ppm, less than 5 ppm, less than 1 ppm, less than 0.5 ppm, less than 0.125 ppm, and most preferably less than 0.05 ppm. 2 O 3 , CdO, CeO 2 , CoO, Cr 2 O 3 , CuO, Dy 2 O 3 , Er 2 O 3 ,EU 2 O 3 , Ga 2 O 3 , Gd 2 O 3 , GeO 2 , HfO 2 , La 2 O 3 , MnO 2 , MoO 3 , Nb 2 O 5 , NiO, PbO, Pr 2 O 3 , PtO 2 , Rb 2 O, Sb 2 O 3 , Sc 2 O 3 , Sm 2 O 3 , SnO 2 , Ta 2 O 5 , Tb 2 O 3 , Tm 2 O 3 , V 2 O 5 , WO 3 , Y 2 O 3 , Yb 2 O 3 and ZnO.

[0152] In one embodiment, the present disclosure provides a method for the preparation of a glass having Zr or ZrO 2or less than 150 ppm, or less than 140 ppm, or less than 130 ppm, or less than 120 ppm, or less than 110 ppm, or less than 50 ppm, or less than 20 ppm, or less than 10 ppm, or less than 5 ppm. Preferably, the glass is Zr-free.

[0153] In a further embodiment, the present disclosure provides a method for producing glass having natural Hf or HfO. 2 is less than 10 ppm, or less than 9 ppm, or less than 8 ppm, or less than 7 ppm, or less than 6 ppm, or less than 5 ppm, or less than 4 ppm, or less than 3 ppm, or less than 2 ppm, or less than 1 ppm. Preferably, the glass is Hf-free.

[0154] In the present invention, the iron content is Fe 2 O 3 This value, as will be appreciated by those skilled in the art, is used to determine the amount of all iron species present in the glass and to calculate the mass percentages, and is expressed as the percentage by weight of Fe. 2 O 3 Therefore, if one mole of iron is in the glass, the mass assumed for the calculation is 159.70 mg of Fe. 2 O 3 This procedure takes into account the fact that the amount of each individual iron species in the glass cannot be determined with certainty or is very difficult to determine. In an embodiment, the glass contains less than 100 ppm Fe, in particular less than 50 ppm, or less than 10 ppm Fe. 2 O 3 In one embodiment having a particularly low iron content, Fe 2 O 3 The percentage of Fe is less than 6 ppm, less than 5 ppm, or less than 4.5 ppm. 2 O 3The content of is optionally in the range of 0 to 4.4 ppm, 0 to 4.0 ppm, 0 to 3.5 ppm, 0 to 2.0 ppm, 0 to 1.75 ppm. In an embodiment, said content may be in the range of 0 to 1.5 ppm, or preferably 0 to 1.25 ppm. In a further embodiment, the glass comprises Fe 2 O 3 It is free of any contaminants.

[0155] In one embodiment, the glass contains less than 100 ppm, in particular less than 50 ppm, or less than 10 ppm TiO 2 Contains particularly low TiO 2 In one embodiment having a TiO content, the glass contains less than 7 ppm, less than 6 ppm, less than 5 ppm, or less than 4 ppm. 2 The content is optionally in the range of 0-6.9 ppm, 0-5.8 ppm, 0-4.7 ppm, 0-3.8 ppm, or 0-2.5 ppm. In one embodiment, the proportion of this component can be in the range of 0-1.5 ppm, 0-1.0 ppm, 0-0.75 ppm, 0-0.5 ppm, and preferably 0-0.25 ppm. In a further embodiment, the glass contains TiO 2 It is free of any contaminants.

[0156] In one embodiment, the glass contains less than 100 ppm, in particular less than 50 ppm, or less than 10 ppm, of arsenic. Glasses containing less than 100 ppm, less than 50 ppm, or less than 10 ppm, of antimony are preferred. Arsenic and antimony are toxic and harmful to the environment, and both of them increase the solarization of the glass.

[0157] Whenever a chemical element (e.g., As, Sb) is indicated herein as being absent, this statement applies to all chemical forms unless otherwise stated in a particular instance. For example, a statement that a glass has an As content of less than 10 ppm refers to the As species present (e.g., As 2 O 3 , As 2 O5 This means that the total mass percentage of all substances (including but not limited to) does not exceed 10 ppm.

[0158] In one embodiment, the glass has a refractive index n d The refractive index may be less than 1.50.

[0159] The method for producing the glass of the present invention comprises the steps of: a) melting glass raw materials at a temperature of 1500°C or higher in a melting tank containing refractory materials; b) optionally fining the melt in a fining vessel containing a refractory material; c) cooling the melt. wherein the glass melt contacts the refractory material of the melting tank and / or optional fining tank, and ZrO 2 is less than 5%, less than 4%, less than 3%, less than 2%, or less than 1% by weight. In preferred embodiments, it is less than 0.25%, less than 0.15%, less than 0.05%, or less than 0.01% by weight. In one embodiment, the refractory material is Zr and / or ZrO 2 Not included.

[0160] Fire-resistant materials should be selected taking into account the acceptable levels of contaminants according to the following formula: Contaminant [ppm] = C uv ×K×A / D In the above formula, C uv is the concentration [in ppm] of the contaminant in the refractory material, and C uv (the sum of Fe, Ti, Pt, Zr and Hf) should be less than 1000 ppm, preferably less than 500 ppm, preferably less than 100 ppm, less than 10 ppm; K is about 10 2is the corrosion rate [mm / d] at a temperature corresponding to the viscosity of the glass melt in dPas, said corrosion rate being the amount of refractory material lost into the melt, expressed as the loss in thickness of material per day in a direction perpendicular to the interface between the refractory material and the glass melt, A is the contact area between the melt and the refractory material [m 2 ], D is the glass throughput [t / d].

[0161] Contaminants should be less than 20 ppm, or less than 10 ppm, or less than 5 ppm.

[0162] In one embodiment, the refractory material is Al 2 O 3 In a preferred embodiment, the composition contains less than 0.25%, less than 0.15%, less than 0.05%, or less than 0.01% by weight of Al. 2 O 3 In one embodiment, the refractory material is Al 2 O 3 Not included.

[0163] It has been found that in the glasses of the present disclosure, reducing conditions during dissolution can increase the absorption at about 200 nm. It is therefore desirable to select reducing dissolution conditions during the manufacture of the glass such that they result in a low transmittance at about 200 nm. This can be achieved, for example, by adding one or more reducing agents, such as sugars (reducing sugars, e.g. sucrose), during dissolution, in particular in an amount of 0.1-1.0 wt. %, e.g. 0.2-0.6 wt. %. However, said conditions can result in a high proportion of Fe, which can adversely affect the transmittance at 220 nm. 2+ It must not be too reducing to avoid species.

[0164] In one embodiment of the present disclosure, when a glass is produced by induction heating the glass melt in a platinum crucible under an argon atmosphere to a temperature of 1500° C., the partial pressure of oxygen (pO 2) is less than 0.5 bar at a temperature of 1500°C.

[0165] pO at 1500°C 2 For example, the pO may be up to 0.4 bar, up to 0.3 bar, or up to 0.2 bar. 2 may be, for example, at least 0.01 bar, at least 0.02 bar, at least 0.05 bar, or at least 0.1 bar. 2 may be, for example, 0.01 bar to 0.5 bar, 0.02 bar to 0.4 bar, 0.05 bar to 0.3 bar, or 0.1 bar to 0.2 bar.

[0166] One aspect of the present disclosure is the use of a crucible or other contact material in direct contact with the molten glass material that is free of contaminants, such as zirconium, hafnium, titanium, platinum, and any other material that interferes with the radiation to be detected.

[0167] In one embodiment of the present disclosure, the crucibles and other contact materials used during the manufacturing process are at least partially made of SiO 2 It is made of.

[0168] When chemical elements are referred to in this application, the description relates to all chemical forms (e.g., all oxides, isotopes, etc.) unless otherwise stated in each individual case. For example, a statement that a glass has a Zr content of less than 100 ppm refers to the Zr species (e.g., Zr 0 , ZrO 2 This means that the sum of the mass fractions of these substances (e.g., 100 ppm or less) does not exceed 100 ppm. [Brief description of the drawings]

[0169] [Figure 1] FIG. 1 shows the emission spectrum of an HOK 4 lamp. [Diagram 2] FIG. 1 shows the results of ZrO2 analysis of various glasses. [Diagram 3] FIG. 1 shows the UV transmittance profile for glass according to the present disclosure. [Figure 4] FIG. 2 shows the UV transmittance profile for the comparative glass. [Diagram 5] FIG. 2 shows the UV transmittance profile for the comparative glass.

[0170] Description of the drawings Figure 1 shows the emission spectrum of an HOK 4 lamp. The wavelength in nm is shown on the x-axis. The relative intensity compared to the maximum intensity is shown on the y-axis.

[0171] Figure 2 shows the ZrO 2 The analytical results are shown. The glass according to the present disclosure is substantially ZrO 2 The comparative glass produced by conventional methods contained significant amounts of ZrO 2 (see also Example 3).

[0172] Figures 3-5 show UV transmittance profiles for glasses according to the present disclosure and comparative glasses using conventional manufacturing methods. Two or three measurements are shown using the same glasses (Inventive Glass 1, Comparative Glasses 2 and 3). Transmittance (y-axis) versus wavelength (x-axis) is shown. For the inventive glasses, the transmittance at lower wavelengths is better. EXAMPLES

[0173] Example 1: Manufacturing process The glasses of the present invention were made by the following process: The contaminant-free raw materials were mixed and then melted in a melting vessel containing refractory material at a temperature of at least 1500°C, at least 1600°C, for about 6 to 8 hours.

[0174] In some embodiments, the melt is further refined in a fining vessel that also contains a refractory material.

[0175] The refractory material of the melting tank and / or fining tank is ZrO 2It is important that the refractory material contains less than 5%, less than 4%, less than 3%, less than 2%, or less than 1% by weight. In preferred embodiments, it is less than 0.25%, less than 0.15%, less than 0.05%, or less than 0.01% by weight. In one embodiment, the refractory material contains Zr and / or ZrO 2 Not included.

[0176] The melt is then cooled and the glass is further processed (eg, by downdraw) into its final form.

[0177] Example 2 Analysis of exemplary glasses Analysis of one of the glasses for trace elements by laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) is presented.

[0178] [Table 8-1]

[0179] [Table 8-2]

[0180] Example 3 Comparative glass In one experiment, a glass according to the present disclosure and ZrO 2 Three comparative UVC glasses (Comparative Glasses 1-3) were produced using a conventional melting method in a crucible containing ZrO 2 The content was analyzed (see FIG. 2). 2 While the three commercial UVC glasses are free of ZrO, they still contain significant amounts of ZrO. 2 It was revealed that it contains.

[0181] In other experiments, two exemplary glasses 1 and 2 according to the present disclosure, and ZrO 2 Another comparative UVC glass (Comparative Glass 4) was produced using a conventional melting method in a crucible containing ZrO 2The glass of the present invention was analyzed for its content (see table). 2 While the three commercial UVC glasses are free of ZrO, they still contain significant amounts of ZrO. 2 The comparison glass was found to be unusable in radiation detectors due to contamination.

[0182] [Table 9]

[0183] Example 4: Corrosion of refractory crucibles A static corrosion test was used to evaluate the corrosion resistance of the materials to glass melts at temperatures between 1550 and 1650°C (heating rates from 60 to a maximum of 100 K / h) for 24 h.

[0184] First, a pre-measured sample is glued in a holder and placed in the intended furnace. A Pt crucible with the appropriate glass melt is placed underneath. Once the furnace has reached the appropriate temperature, the sample is immersed in the glass melt and pulled out again after the appropriate holding time at the test temperature.

[0185] Corrosion in glass vessels usually occurs on one side only, therefore, corrosion removal of corroded specimens at and below the flashing joints is also evaluated on one side removal only.

[0186] The depth of the flashing joint and the average removal are used to determine the corrosion removal considered below the flashing joint. In each case, the calculation is performed on one half of the sample.

[0187] To calculate removal, the following formula is used:

number

[0188] where d i denotes the average thickness of the specimen after testing at point i, and S xdenotes the thickness at the measurement points on sample 1 (x=1) and sample 2 (x=2), A denotes the average removal on one side at point i, and d a denotes the starting thickness of the sample. This calculation is repeated for the flashing joint (the thinnest point of the sample) and four other points. It is then averaged again over the four points below the flashing joint.

[0189]

number

[0190] Some materials grow or shrink, resulting in the specified value for removal, and the shrinkage factor (Sw) of the material is calculated as follows:

number

[0191] d at the top point of the sample a (initial sample thickness) and S x (specimen thickness after test) and (measured within the bonded area, if possible, without glass vapor contact).

[0192] Material for refractory crucibles containing the following components: [Table 10]

[0193] Surprisingly, it was found that although the new material corrodes faster in the glass melt, it is significantly less contaminated with Zr, Cr, Fe, Mn, Pt, Ti and Ni compared to conventional zirconium aluminium silicate (AZS) or Korvisit A® materials.

[0194] For example, contamination of the glass melt when using AZS is shown as follows: [Table 11]

[0195] Example 5: Contamination with radionuclides The comparative glass produced in a glass melting crucible made of AZS (with 40% by mass of Zr) was analyzed by gamma spectrometry. Only natural radionuclides from the U-238-, U-235- and Th-232 decay series were detected, which may be contaminants with zirconium as present in AZS refractory materials. Ir-192 and K-40 were below the detection limit, respectively. In gamma spectrometry, the daughter products of Ra-228 show signals at similar energies as Ir-192, which, depending on the type of measuring device, may lead to false positive results for Ir-192.

[0196] [Table 12]

[0197] In a second experiment, a comparative glass produced in another glass melting crucible made of AZS (with 65% Zr by mass) was analyzed by gamma spectrometry. Only natural radionuclides from the U-238-, U-235- and Th-232 decay series were detected, which may be contaminants with zirconium as present in AZS refractory materials. Ir-192 and K-40 were below the detection limit, respectively. In gamma spectrometry, the daughter products of Ra-228 show signals at similar energies as Ir-192, which, depending on the type of measuring device, may lead to false positive results for Ir-192.

[0198] [Table 13]

[0199] Example 6 Neutron detection Neutron sensitive scintillation glass fiber detectors are tested using glass fibers made from inventive glasses 1 and 2 (see Example 3) and comparative glass 4 (see Example 3).

[0200] The detection of neutron absorption varies by only ±3% for the inventive glasses, while the variation of neutron absorption with comparative glass 4 varies by approximately ±10%. Furthermore, for comparison, the specific thermal neutron detection efficiency as a function of the thermal neutron beam position along the foil span is experimentally measured for both detector configurations. Detection efficiencies of 16.16% (comparative glass 4) versus 44.08% (inventive glass 2) and 53.04% (inventive glass 1), respectively, are measured.

[0201] This demonstrates the superiority of the glasses of the present invention when used in neutron detectors.

Claims

1. A glass having a transmittance of at least 65.0% at a wavelength of 260 nm (with a reference thickness of 1.0 mm), wherein the glass contains ZrO 2 The glass wherein the amount is less than 150 ppm.

2. Hfo in the glass 2 The glass according to claim 1, wherein the amount is less than 10 ppm.

3. The glass according to claim 1 or 2, wherein the glass has an emission of less than 4.42 becquerels of alpha particles per gram of glass.

4. Fe in the glass 2 O 3 MoO 3 and WO 3 The glass according to claim 1 or 2, wherein the amount of one or more of the elements is less than 10 ppm.

5. TiO in the glass 2 The glass according to claim 1 or 2, wherein the amount of is less than 20 ppm.

6. The following composition: Ingredient content Si 4+ 52-71% cation Al 3+ 0 to 8 cationic % B 3+ 0-35% cation Li + 0-7% cation Na + 0-17% cation K + 0-14% cation Mg 2+ 0-6% cations Ca 2+ 0-2 cation percentages Sr 2+ 0-4 cation percentage Ba 2+ 0-4 cation percentage R + Total 5-30% cations R 2+ Total 0-5 cation percentage The glass according to claim 1 or 2, comprising in the indicated amount (cation %).

7. F - The glass may contain 0 to 3% by mass, and / or Cl - The glass according to claim 6, wherein the anion can be present in the glass in an amount of 0 to 1% by mass, and at least 96% by mass of the anion can be present as oxygen.

8. The glass according to claim 1 or 2, wherein the transmittance at a wavelength of 260 nm exceeds 75% (at a standard thickness of 1 mm).

9. The glass according to claim 1 or 2, wherein the amount of one or more oxides of gallium, uranium, thorium, yttrium, and thallium in the glass is up to 3 ppm.

10. A method for manufacturing glass according to claim 1 or 2, comprising the following steps: a) The step of melting the glass raw material in a melting tank containing refractory material, b) Optionally, a step of clarifying the molten material in a clarifying tank containing refractory material, c) The step of cooling the molten material. Includes, The molten glass comes into contact with the refractory material of the melting tank and / or any clarification tank, ZrO in the refractory material of the melting tank and any clarifying tank 2 The proportion is less than 5% by mass. The aforementioned method.

11. The method according to claim 10, wherein the melting step a) includes a temperature of 1500°C or higher.

12. The aforementioned fire-resistant material is Al 2 O 3 The method according to claim 10, comprising less than 5% by mass of the above.

13. The method according to claim 10, wherein reducing conditions are applied during melting.

14. Use of the glass according to claim 1 or 2 for radiation and / or particle detectors.

15. The use of glass according to claim 14, wherein the detector is selected from a neutron detector, a neutrino detector, a photomultiplier tube, or a UV detector.

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