A quartz tube with low ultraviolet transmission and a preparation method thereof

Abstract

The application relates to the technical field of quartz tube production, in particular to a quartz tube with low ultraviolet transmittance and a preparation method thereof; the quartz tube is made of the following raw materials in parts by weight: 40-50 parts of quartz sand, 4-8 parts of a functional additive, 4-6 parts of a synergistic additive, 6-10 parts of high borosilicon, 10-14 parts of boron oxide, 3-5 parts of zinc oxide, 5-7 parts of praseodymium oxide and 6-8 parts of aluminum nitrate; the quartz sand, the functional additive, the synergistic additive, the high borosilicon, the boron oxide, the zinc oxide, the praseodymium oxide and the aluminum nitrate are fully mixed at normal temperature to obtain a mixed base material, the mixed base material is put into a continuous smelting furnace to smelt, a molten raw material is obtained, the molten raw material is drawn and cut to obtain the quartz tube, and then the quartz tube is cleaned, dried and inspected in sequence; the prepared quartz tube not only has excellent low ultraviolet transmittance and high light transmittance, but also has the advantage of high bending strength.

Description

Technical Field

[0001] This invention relates to the field of quartz tube manufacturing technology, specifically to a low ultraviolet transmittance quartz tube and its preparation method. Background Technology

[0002] Quartz tubes are made of silicon dioxide, a special industrial glass and an excellent basic material. Quartz glass possesses a range of superior physical and chemical properties. It is used in electric heaters, electric stoves, and electric warmers for its heating function.

[0003] Because current ordinary UV-filtering quartz glass tubes cannot completely filter out ultraviolet light, excessive transmittance can be harmful to human health when used in lamps. Furthermore, they have limitations in terms of pressure resistance and safety. Therefore, effectively improving the quality of quartz tubes has become a crucial issue that urgently needs to be addressed by my country's quartz tube manufacturing industry.

[0004] Therefore, the present invention provides a quartz tube with low ultraviolet transmittance and a method for preparing the same, in order to solve the related technical problems mentioned above. Summary of the Invention

[0005] The purpose of this invention is to provide a low ultraviolet transmittance quartz tube and its preparation method. The low ultraviolet transmittance quartz tube prepared by this invention not only has excellent low ultraviolet transmittance and high light transmittance, but also has the advantage of high flexural strength.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A first aspect of the present invention provides a quartz tube with low ultraviolet transmittance, said quartz tube being made from the following raw materials in parts by weight: 40-50 parts quartz sand, 4-8 parts functional additives, 4-6 parts synergistic additives, 6-10 parts high borosilicate, 10-14 parts boron oxide, 3-5 parts zinc oxide, 5-7 parts praseodymium oxide, and 6-8 parts aluminum nitrate.

[0008] The present invention is further configured such that the silica content in the quartz sand is ≥99%, and the impurity weight content is less than 10ppm.

[0009] A further provision of the present invention is that the preparation process of the functional additive is as follows:

[0010] Neodymium carbonate was placed in an appropriate amount of nitric acid at a solid-liquid ratio of 0.02 to 0.05 g / mL. After the neodymium carbonate was completely dissolved, ammonium nitrate and a combustion aid were added to the resulting solution. The solution was then concentrated to a viscous state at 60 to 70°C.

[0011] The obtained viscous product was placed in a muffle furnace for 20-22 minutes, then removed from the muffle furnace and cooled to room temperature. The cooled product was washed 2-4 times with deionized water and then dried at 80-82°C to obtain the dried product.

[0012] The dried product was ultrasonically dispersed in an appropriate amount of mixed liquid at a solid-liquid ratio of 0.12–0.14 g / mL for 20–30 min. Then, 2.5% by weight of nano-titanium dioxide and 1.2% by weight of 25 wt% ammonia water were added to the dispersion. The mixture was stirred and mixed at 42–46 °C and 80–90 r / min for 4 h. The resulting product was then filtered and dried at 80–82 °C to obtain the functional additive.

[0013] The present invention is further configured such that: the amount of ammonium nitrate added is 2.5 to 4.5% of the mass of neodymium carbonate, and the amount of combustion improver added is 3.2 to 5.2% of the mass of neodymium carbonate.

[0014] A further feature of this invention is that the combustion aid is selected from either ethylene glycol or glycine.

[0015] A further feature of the present invention is that the temperature of the muffle furnace is 460–480°C.

[0016] A further embodiment of the present invention is that the mixture is composed of ethanol and ultrapure water at a mass ratio of 0.25 to 0.29:1.

[0017] A further provision of the present invention is that the preparation process of the synergistic adjuvant is as follows:

[0018] Cerium nitrate hexahydrate, cuprous chloride, ferrous chloride, and water were mixed at a mass ratio of 0.22–0.24:0.14–0.16:0.08–0.12:1 at 800–840 rpm for 20–30 min. The mixture was then heated to 60–64 °C under a nitrogen atmosphere and treated at 120–140 rpm for 120–140 min.

[0019] Carbon dioxide gas was introduced into the obtained composite solution. After the introduction of carbon dioxide gas was completed, the temperature was raised to 96-98℃ for 40-50 min, and then raised to 130-150℃ for 60-70 min. The resulting synergistic solution was cooled to room temperature, filtered, and dried at 60-64℃ to obtain the synergistic adjuvant.

[0020] The present invention is further configured such that the amount of carbon dioxide gas introduced is 0.032 to 0.042 g / min, and the introduction time is 3 to 6 min.

[0021] A second aspect of the present invention also provides a method for preparing a low ultraviolet transmittance quartz tube as described above, comprising the following steps:

[0022] Step 1: Accurately weigh the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate respectively. Then, mix the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate thoroughly at room temperature to obtain a mixed base material.

[0023] Step 2: The mixed base material is put into a continuous melting furnace and melted at 2050-2250℃ to obtain molten raw material;

[0024] Step 3: The molten raw material is drawn and cut to obtain a quartz tube, which is then washed, dried and inspected to finally obtain a finished quartz tube with low ultraviolet transmittance.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] The low UV transmittance quartz tube prepared by this invention uses quartz sand, functional additives, synergistic additives, high borosilicate silicon, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate as raw materials. These materials are thoroughly mixed at room temperature to obtain a mixed base material. This mixed base material is then melted in a continuous melting furnace to obtain a molten raw material. Finally, the molten raw material is drawn and cut to obtain quartz tubes. These tubes are then washed, dried, and inspected to obtain the final low UV transmittance quartz tube. The prepared quartz tube not only has excellent low UV transmittance and high luminous efficacy but also high flexural strength. The low UV transmittance quartz tube produced by this invention has a broader market prospect and is more suitable for widespread application. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a statistical chart of the ultraviolet light transmittance of the present invention;

[0029] Figure 2 This is a statistical chart of the flexural strength of the present invention. Detailed Implementation

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1

[0032] This embodiment provides a quartz tube with low ultraviolet transmittance, which is made from the following raw materials in parts by weight: 40 parts quartz sand, 4 parts functional additives, 4 parts synergistic additives, 6 parts high borosilicate, 10 parts boron oxide, 3 parts zinc oxide, 5 parts praseodymium oxide and 6 parts aluminum nitrate.

[0033] The silica content in the quartz sand is ≥99%, and the impurity content is less than 10 ppm by weight.

[0034] The preparation process of functional additives is as follows:

[0035] Neodymium carbonate was placed in an appropriate amount of nitric acid at a solid-liquid ratio of 0.02 g / mL. After the neodymium carbonate was completely dissolved, ammonium nitrate and a combustion aid were added to the resulting solution. The solution was then concentrated to a viscous state at 60°C.

[0036] The obtained viscous product was placed in a muffle furnace for 20 minutes, then removed from the muffle furnace and cooled to room temperature. The cooled product was washed twice with deionized water and then dried at 80°C to obtain the dried product.

[0037] The dried product was ultrasonically dispersed in an appropriate amount of mixed liquid at a solid-liquid ratio of 0.12 g / mL for 20 min. Then, 2.5% by weight of nano-titanium dioxide and 1.2% by weight of 25 wt% ammonia water were added to the dispersion. The mixture was stirred and mixed at 42℃ and 80 r / min for 4 h. The resulting product was then filtered and dried at 80℃ to obtain the functional additive.

[0038] Furthermore, the amount of ammonium nitrate added is 2.5% of the mass of neodymium carbonate, and the amount of combustion improver added is 3.2% of the mass of neodymium carbonate.

[0039] Ethylene glycol is selected as the combustion improver.

[0040] The temperature of the muffle furnace is 460℃.

[0041] The mixture is made by mixing ethanol and ultrapure water at a mass ratio of 0.25:1.

[0042] The preparation process of the synergistic agent is as follows:

[0043] Cerium nitrate hexahydrate, cuprous chloride, ferrous chloride and water were mixed at a mass ratio of 0.22:0.14:0.08:1 at 800 r / min for 20 min, and then heated to 60 °C under a nitrogen atmosphere and treated at 120 r / min for 120 min.

[0044] Carbon dioxide gas was introduced into the obtained composite solution. After the carbon dioxide gas was introduced, the temperature was raised to 96℃ for 40 min, and then raised to 130℃ for 60 min. The resulting synergistic solution was cooled to room temperature, filtered, and dried at 60℃ to obtain the synergistic adjuvant.

[0045] Furthermore, the carbon dioxide gas flow rate was 0.032 g / min, and the flow time was 3 min.

[0046] Furthermore, this embodiment also provides a method for preparing a low ultraviolet transmittance quartz tube as described above, comprising the following steps:

[0047] Step 1: Accurately weigh the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate respectively. Then, mix the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate thoroughly at room temperature to obtain a mixed base material.

[0048] Step 2: The mixed base material is put into a continuous melting furnace and melted at 2050℃ to obtain molten raw material;

[0049] Step 3: The molten raw material is drawn and cut to obtain a quartz tube, which is then washed, dried and inspected to finally obtain a finished quartz tube with low ultraviolet transmittance.

[0050] Example 2

[0051] This embodiment provides a quartz tube with low ultraviolet transmittance, which is made of the following raw materials in parts by weight: 45 parts quartz sand, 6 parts functional additives, 5 parts synergistic additives, 8 parts high borosilicate, 12 parts boron oxide, 4 parts zinc oxide, 6 parts praseodymium oxide and 7 parts aluminum nitrate.

[0052] The silica content in the quartz sand is ≥99%, and the impurity content is less than 10 ppm by weight.

[0053] The preparation process of functional additives is as follows:

[0054] Neodymium carbonate was placed in an appropriate amount of nitric acid at a solid-liquid ratio of 0.03 g / mL. After the neodymium carbonate was completely dissolved, ammonium nitrate and a combustion aid were added to the resulting solution. The solution was then concentrated to a viscous state at 65°C.

[0055] The obtained viscous product was placed in a muffle furnace for 21 min, then removed from the muffle furnace and cooled to room temperature. The cooled product was washed three times with deionized water and then dried at 81°C to obtain the dried product.

[0056] The dried product was ultrasonically dispersed in an appropriate amount of mixed liquid at a solid-liquid ratio of 0.13 g / mL for 25 min. Then, 2.5% by weight of nano-titanium dioxide and 1.2% by weight of 25 wt% ammonia water were added to the resulting dispersion. The mixture was stirred and mixed at 44 °C and 85 r / min for 4 h. The resulting product was then filtered and dried at 81 °C to obtain the functional additive.

[0057] Furthermore, the amount of ammonium nitrate added is 3.5% of the mass of neodymium carbonate, and the amount of combustion improver added is 4.2% of the mass of neodymium carbonate.

[0058] Glycine was selected as the combustion improver.

[0059] The temperature of the muffle furnace is 470℃.

[0060] The mixture was prepared by mixing ethanol and ultrapure water at a mass ratio of 0.27:1.

[0061] The preparation process of the synergistic agent is as follows:

[0062] Cerium nitrate hexahydrate, cuprous chloride, ferrous chloride and water were mixed at a mass ratio of 0.23:0.15:0.1:1 for 25 min at 820 r / min. Then, the mixture was heated to 62 °C under a nitrogen atmosphere and treated at 130 r / min for 130 min.

[0063] Carbon dioxide gas was introduced into the obtained composite solution. After the carbon dioxide gas was introduced, the temperature was raised to 97°C for 45 min, and then raised to 140°C for 65 min. The resulting synergistic solution was cooled to room temperature, filtered, and dried at 62°C to obtain the synergistic adjuvant.

[0064] Furthermore, the carbon dioxide gas flow rate was 0.037 g / min, and the flow time was 4 min.

[0065] Furthermore, this embodiment also provides a method for preparing a low ultraviolet transmittance quartz tube as described above, comprising the following steps:

[0066] Step 1: Accurately weigh the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate respectively. Then, mix the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate thoroughly at room temperature to obtain a mixed base material.

[0067] Step 2: The mixed base material is put into a continuous melting furnace and melted at 2150℃ to obtain molten raw material;

[0068] Step 3: The molten raw material is drawn and cut to obtain a quartz tube, which is then washed, dried and inspected to finally obtain a finished quartz tube with low ultraviolet transmittance.

[0069] Example 3

[0070] This embodiment provides a quartz tube with low ultraviolet transmittance, which is made from the following raw materials in parts by weight: 50 parts quartz sand, 8 parts functional additives, 6 parts synergistic additives, 10 parts high borosilicate, 14 parts boron oxide, 5 parts zinc oxide, 7 parts praseodymium oxide and 8 parts aluminum nitrate.

[0071] The silica content in the quartz sand is ≥99%, and the impurity content is less than 10 ppm by weight.

[0072] The preparation process of functional additives is as follows:

[0073] Neodymium carbonate was placed in an appropriate amount of nitric acid at a solid-liquid ratio of 0.05 g / mL. After the neodymium carbonate was completely dissolved, ammonium nitrate and a combustion aid were added to the resulting solution. The solution was then concentrated to a viscous state at 70°C.

[0074] The obtained viscous product was placed in a muffle furnace for 22 min, then removed from the muffle furnace and cooled to room temperature. The cooled product was washed four times with deionized water and then dried at 82°C to obtain the dried product.

[0075] The dried product was ultrasonically dispersed in an appropriate amount of mixed solution at a solid-liquid ratio of 0.14 g / mL for 30 min. Then, 2.5% by weight of nano-titanium dioxide and 1.2% by weight of 25 wt% ammonia water were added to the resulting dispersion. The mixture was stirred and mixed at 46 °C and 90 r / min for 4 h. The resulting product was then filtered and dried at 82 °C to obtain the functional additive.

[0076] Furthermore, the amount of ammonium nitrate added is 4.5% of the mass of neodymium carbonate, and the amount of combustion improver added is 5.2% of the mass of neodymium carbonate.

[0077] Ethylene glycol is selected as the combustion improver.

[0078] The temperature of the muffle furnace is 480℃.

[0079] The mixture was prepared by mixing ethanol and ultrapure water at a mass ratio of 0.29:1.

[0080] The preparation process of the synergistic agent is as follows:

[0081] Cerium nitrate hexahydrate, cuprous chloride, ferrous chloride and water were mixed at a mass ratio of 0.24:0.16:0.12:1 for 30 min at 840 r / min. Then, the mixture was heated to 64 °C under a nitrogen atmosphere and treated at 140 r / min for 140 min.

[0082] Carbon dioxide gas was introduced into the obtained composite solution. After the carbon dioxide gas was introduced, the temperature was raised to 98℃ for 50 min, and then raised to 150℃ for 70 min. The resulting synergistic solution was cooled to room temperature, filtered, and dried at 64℃ to obtain the synergistic adjuvant.

[0083] Furthermore, the carbon dioxide gas flow rate was 0.042 g / min, and the flow time was 6 min.

[0084] Furthermore, this embodiment also provides a method for preparing a low ultraviolet transmittance quartz tube as described above, comprising the following steps:

[0085] Step 1: Accurately weigh the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate respectively. Then, mix the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate thoroughly at room temperature to obtain a mixed base material.

[0086] Step 2: The mixed base material is put into a continuous melting furnace and melted at 2250℃ to obtain molten raw material;

[0087] Step 3: The molten raw material is drawn and cut to obtain a quartz tube, which is then washed, dried and inspected to finally obtain a finished quartz tube with low ultraviolet transmittance.

[0088] Comparative Example 1: The preparation method and specific ratio of raw materials for the low UV transmittance quartz tube provided in this example are roughly the same as those in Example 1. The main difference is that this example does not contain functional additives.

[0089] Comparative Example 2: The preparation method and specific ratio of raw materials for the low UV transmittance quartz tube provided in this example are roughly the same as those in Example 1. The main difference is that neodymium carbonate is replaced by cerium carbonate in this example.

[0090] Comparative Example 3: The preparation method and specific ratio of raw materials for the low UV transmittance quartz tube provided in this example are roughly the same as those in Example 1. The main difference is that this example does not contain any synergistic additives.

[0091] Effect test

[0092] Quartz tubes prepared by Examples 1 to 3 of the present invention are designated as Experimental Examples 1 to 3; quartz tubes prepared by Comparative Examples 1 to 3 are designated as Comparative Examples 1 to 3; and the performance of each group of quartz tube samples is then tested.

[0093] Test 1: Transmittance test and result analysis:

[0094] According to the testing standard of ISO 9050:2003, the ultraviolet light transmittance (wavelength 190-400nm) and visible light transmittance of each group of quartz tubes were tested. The relevant data are recorded in Table 1.

[0095] Table 1: Experimental Data Recording Table

[0096] Example 1 group 6.5 88.2 Example 2 group 6.4 88.1 Example 3 6.5 88.1 Comparison Group 1 29.5 75.0 Comparison of 2 groups 11.2 85.5 Comparison of 3 groups 22.5 82.2

[0097] From Table 1 and Figure 1 It can be seen that, compared with the control group, the quartz tubes of Examples 1-3 significantly reduced ultraviolet light transmittance and increased visible light transmittance. Meanwhile, the differences between the example groups were not significant. These results indicate that the quartz tubes of Examples 1-3 have a significant effect of low ultraviolet transmittance and high light transmittance.

[0098] To verify the effects of each component of this additive, comparative experiments 1 to 3 were conducted.

[0099] The main difference in the raw material ratio between Comparison Group 1 and Example Group 1 lies in the absence of functional additives. Compared with Example Group 1, Comparison Group 1 showed a 23% increase in ultraviolet light transmittance and a 13.1% decrease in visible light transmittance. This result indicates that functional additives play an important role in the ultraviolet and visible light transmittance of quartz tubes.

[0100] The main difference in the raw material ratios of the quartz tubes in Comparison Group 2 and Example Group 1 was that neodymium carbonate was replaced by cerium carbonate. Compared with Example Group 1, the ultraviolet light transmittance of Comparison Group 2 increased by 4.7%, while the visible light transmittance decreased by 2.7%. This result indicates that replacing neodymium carbonate with cerium carbonate affects the ultraviolet and visible light transmittance of quartz tubes.

[0101] The main difference in the raw material formulation between Group 3 and Group 1 was the absence of synergistic additives. Compared to Group 1, Group 3 showed a 16% increase in ultraviolet transmittance and a 6% decrease in visible light transmittance. This result indicates that synergistic additives play a significant role in the ultraviolet and visible light transmittance of quartz tubes.

[0102] Test Experiment 2, Mechanical Performance Test and Result Analysis:

[0103] The flexural strength was determined using a universal testing machine, and the relevant data are recorded in Table 2.

[0104] Table 2: Experimental Data Recording Table

[0105] Example 1 group 150 Example 2 group 149 Example 3 150 Comparison Group 1 135 Comparison of 2 groups 149 Comparison of 3 groups 125

[0106] From Table 2 and Figure 2 It can be seen that, compared with the control group, the quartz tubes of Examples 1-3 have significantly improved mechanical strength properties, while the differences between the example groups are not significant. These results indicate that the quartz tubes of Examples 1-3 have a significantly higher flexural strength.

[0107] To verify the effects of each component of this additive, comparative experiments 1 to 3 were conducted.

[0108] The main difference in the raw material ratio between Comparison Group 1 and Example Group 1 lies in the absence of functional additives. Compared to Example Group 1, the flexural strength of Comparison Group 1 decreased by 15 MPa. This result indicates that functional additives play a role in the flexural strength of quartz tubes.

[0109] The main difference in the raw material ratio between the quartz tubes in Group 2 and Example 1 was that neodymium carbonate was replaced by cerium carbonate. Compared with Example 1, the flexural strength of Group 2 decreased by 1 MPa. This result indicates that replacing neodymium carbonate with cerium carbonate has little impact on the flexural strength of quartz tubes.

[0110] The main difference in the raw material formulation between Group 3 and Example 1 was the absence of synergistic additives. Compared to Example 1, the flexural strength of Group 3 decreased by 25 MPa. This result indicates that synergistic additives play an important role in the flexural strength of quartz tubes.

[0111] As described above, the low UV transmittance quartz tube prepared by this invention not only effectively enhances UV resistance but also promotes visible light transmission; moreover, it possesses high flexural strength. This indicates that the low UV transmittance quartz tube produced by this invention has a broader market prospect and is more suitable for widespread application.

[0112] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0113] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A quartz tube with low ultraviolet transmittance, characterized in that: The quartz tube is made from the following raw materials in parts by weight: 40-50 parts quartz sand, 4-8 parts functional additives, 4-6 parts synergistic additives, 6-10 parts high borosilicate, 10-14 parts boron oxide, 3-5 parts zinc oxide, 5-7 parts praseodymium oxide and 6-8 parts aluminum nitrate. The preparation process of the functional additive is as follows: Neodymium carbonate was placed in an appropriate amount of nitric acid at a solid-liquid ratio of 0.02 to 0.05 g / mL. After the neodymium carbonate was completely dissolved, ammonium nitrate and a combustion aid were added to the resulting solution. The solution was then concentrated to a viscous state at 60 to 70°C. The obtained viscous product was placed in a muffle furnace for 20-22 minutes, then removed from the muffle furnace and cooled to room temperature. The cooled product was washed 2-4 times with deionized water and then dried at 80-82°C to obtain the dried product. The dried product was ultrasonically dispersed in an appropriate amount of mixed liquid at a solid-liquid ratio of 0.12–0.14 g / mL for 20–30 min. Then, 2.5% by weight of nano-titanium dioxide and 1.2% by weight of 25 wt% ammonia water were added to the dispersion. The mixture was stirred and mixed at 42–46 °C and 80–90 r / min for 4 h. The resulting product was then filtered and dried at 80–82 °C to obtain the functional additive. The preparation process of the synergistic agent is as follows: Cerium nitrate hexahydrate, cuprous chloride, ferrous chloride, and water were mixed at a mass ratio of 0.22–0.24:0.14–0.16:0.08–0.12:1 at 800–840 rpm for 20–30 min. The mixture was then heated to 60–64 °C under a nitrogen atmosphere and treated at 120–140 rpm for 120–140 min. Carbon dioxide gas is introduced into the obtained composite solution. After the introduction of carbon dioxide gas is completed, the temperature is raised to 96-98℃ for 40-50 min, and then raised to 130-150℃ for 60-70 min. The resulting synergistic solution is cooled to room temperature, filtered, and dried at 60-64℃ to obtain the synergistic adjuvant.

2. A low ultraviolet transmittance quartz tube according to claim 1, characterized in that: The amount of ammonium nitrate added is 2.5 to 4.5% of the mass of neodymium carbonate, and the amount of combustion improver added is 3.2 to 5.2% of the mass of neodymium carbonate.

3. A low ultraviolet transmittance quartz tube according to claim 1, characterized in that: The combustion aid is selected from either ethylene glycol or glycine.

4. A low ultraviolet transmittance quartz tube according to claim 1, characterized in that: The temperature of the muffle furnace is 460–480°C.

5. A quartz tube with low ultraviolet transmittance according to claim 2, characterized in that: The mixture is prepared by mixing ethanol and ultrapure water at a mass ratio of 0.25 to 0.29:

1.

6. A quartz tube with low ultraviolet transmittance according to claim 1, characterized in that: The carbon dioxide gas is introduced at a rate of 0.032–0.042 g / min for a duration of 3–6 min.

7. A method for preparing a low ultraviolet transmittance quartz tube according to any one of claims 1 to 6, characterized in that, Includes the following steps: Step 1: Accurately weigh the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate respectively. Then, mix the quartz sand, functional additives, synergistic additives, high borosilicate, boron oxide, zinc oxide, praseodymium oxide, and aluminum nitrate thoroughly at room temperature to obtain a mixed base material. Step 2: The mixed base material is put into a continuous melting furnace and melted at 2050-2250℃ to obtain molten raw material; Step 3: The molten raw material is drawn and cut to obtain a quartz tube, which is then washed, dried and inspected to finally obtain a finished quartz tube with low ultraviolet transmittance.

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