Ultraviolet optical filter for disinfection and coating method thereof

Abstract

The invention discloses an ultraviolet optical filter for disinfection and a coating method thereof, and relates to the technical field of optical thin film manufacturing. According to the invention, high-purity fused JGS1 quartz glass is used as a coating substrate, lanthanum fluoride and magnesium fluoride are used as coating materials, so that the ultraviolet optical filter with higher transmittance is prepared, and coating is carried out in a thermal resistance evaporation mode in a vacuum environment, so that the stability of fluoride is enhanced, the transmittance of the ultraviolet optical filter is improved, and the service life of the ultraviolet optical filter is prolonged. According to the present invention, the film material is adopted, and the small amount of the silver fluoride is doped in the film material, such that the fluorine loss phenomenon existing in the film coating process of the fluoride can be solved, the large temperature drift phenomenon occurring after the temperature rising during the use of the traditional ultraviolet light filter can be reduced, and the energy transmission efficiency of the ultraviolet sterilization lamp can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of optical film manufacturing, in particular to an ultraviolet filter for disinfection and a coating method thereof. Background Art

[0002] The effect of ultraviolet rays is to destroy the protein structure of organisms, thereby achieving the effect of sterilization and disinfection. Due to its non-targetedness, it can inactivate all organisms and is harmful to the human body. Therefore, it is necessary to select ultraviolet rays of a certain wavelength for transmission, and ultraviolet light in other bands needs to be cut off. Due to the particularity and stability of the material, it is necessary to deposit thin films at the molecular atomic level under vacuum conditions. Vacuum coating equipment mainly refers to a type of coating that needs to be performed under a higher vacuum degree. There are many types, including vacuum resistance heating evaporation, electron gun heating evaporation, magnetron sputtering, MBE molecular beam epitaxy, PLD laser sputtering deposition, ion beam sputtering and many other types.

[0003] In the past, hafnium oxide and silicon dioxide were usually used for coating. The combination of these two materials has the following problems: first, the transmittance is not high before 220nm in the ultraviolet band, which affects the transmission efficiency of ultraviolet light; second, the transmittance will decrease after the lens has been working for a period of time, and the transmission energy at the corresponding special wavelength position will drop seriously. This is because the processes used for hafnium oxide and silicon dioxide have serious problems with temperature drift of the lenses after coating. Since the environment in which the product is used has a large temperature difference of -40℃ to 80℃, this poses a challenge to the temperature drift of the product. Summary of the invention

[0004] The object of the present invention is to provide an ultraviolet filter for disinfection and a preparation method thereof, so as to solve the problems existing in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for preparing a UV filter for disinfection, comprising the following preparation steps: (1) Ultrasonic cleaning or manual wiping of the substrate to remove dirt and dust on the surface of the lens; (2) After the substrate is cleaned, clean the ion source and obtain a UV filter for disinfection.

[0006] Furthermore, the substrate in step (1) is UV-grade fused quartz JGS1.

[0007] Furthermore, the cleaning agent used in step (1) is ether.

[0008] Furthermore, the ultrasonic cleaning frequency in step (1) is 21 kHz and the time is 15 min.

[0009] Furthermore, the process parameters for cleaning the ion source in step (2) are: temperature of 400° C., voltage of 300 V, current of 3 A, and time of 5 min.

[0010] A coating method for an ultraviolet filter for disinfection includes the following preparation steps: (1) Under vacuum at 400°C, a thermal resistance evaporation method was used to coat a UV filter for disinfection. The resistance evaporation current was 88A. The first layer was lanthanum fluoride, and the second layer was magnesium fluoride. Four layers were coated in sequence, and then the temperature was kept for 20 minutes, and finally cooled for 2.5 hours. (2) The anti-virus UV filter after coating is cleaned with an organic solvent, aged, and then cleaned with an organic solvent again and stored in a vacuum.

[0011] Furthermore, the vacuum degree of step (1) is 3×10 -3 Pa.

[0012] Furthermore, the thickness of each coating layer in step (1) is 10-90 nm, and the film material of each coating layer contains 10% silver fluoride.

[0013] Furthermore, the organic solvent in step (2) is ethanol.

[0014] Furthermore, the aging process conditions in step (2) are: humidity of 85%, temperature of 85° C., and time of 50 h.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention adopts high-purity molten JGS1 quartz glass as a coating substrate, and adopts lanthanum fluoride and magnesium fluoride as coating materials, so as to prepare an ultraviolet filter with higher transmittance, and performs coating by thermal resistance evaporation in a vacuum environment, so as to enhance the stability of fluoride, improve the transmittance of the ultraviolet filter, reduce the loss at ultraviolet 220nm, and dope a small amount of silver fluoride in the film material, so as to solve the fluoride loss phenomenon existing in the coating process of fluoride, reduce the large temperature drift phenomenon of the traditional ultraviolet filter due to the temperature rise during use, which affects the use effect, and also improve the energy transmission efficiency of the ultraviolet germicidal lamp. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 This is a comparison chart of the two filters; Figure 2 Design of spectrum of magnesium fluoride material with absorption of 0.4% at short wavelength under new structure; Figure 3This is a high and low temperature drift experiment diagram using hafnium oxide and silicon dioxide; Figure 4 This is a high and low temperature drift experiment diagram of Example 1. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] Example 1

[0019] (1) Ultrasonic cleaning of UV-grade fused quartz JGS1 substrates with ether at a frequency of 21 kHz for 15 min, or manual wiping to remove dirt and dust from the lens surface; (2) After the substrate is cleaned, the ion source is cleaned with the following process parameters: temperature of 400°C, voltage of 300V, current of 3A, time of 5min, and a UV filter for disinfection.

[0020] (3) At 400°C and vacuum degree of 3×10 -3 Pa environment, thermal resistance evaporation coating was carried out on the anti-virus UV filter, the resistance evaporation current was 88A, the first layer was lanthanum fluoride, the second layer was magnesium fluoride, and 4 layers were coated in sequence, the thickness of each coating layer was 50nm, and the composition of the film material of each coating layer contained 10% silver fluoride, and then kept warm for 20 minutes, and finally cooled for 2.5 hours; (4) The anti-virus UV filter after coating was cleaned with ethanol, aged for 50 h in an environment with a humidity of 85% and a temperature of 85°C, and then cleaned with ethanol and stored in a vacuum.

[0021] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for preparing an ultraviolet filter for disinfection, characterized in that: The method comprises the following preparation steps: (1) Ultrasonic cleaning of the substrate; (2) After the substrate is cleaned, clean the ion source and obtain a UV filter for disinfection.

2. The method for preparing a virus-killing ultraviolet filter according to claim 1, characterized in that: The substrate in step (1) is UV-grade fused quartz JGS1.

3. The method for preparing a virus-killing ultraviolet filter according to claim 1, characterized in that: The cleaning agent used in step (1) is ether.

4. The method for preparing a virus-killing ultraviolet filter according to claim 1, characterized in that: The ultrasonic cleaning frequency in step (1) is 21 kHz and the time is 15 min.

5. The method for preparing a virus-killing ultraviolet filter according to claim 1, characterized in that: The process parameters for cleaning the ion source in step (2) are: temperature of 400°C, voltage of 300V, current of 3A, and time of 5min.

6. A method for coating a UV filter for disinfection, characterized in that: The method comprises the following preparation steps: (1) Under vacuum at 400°C, a thermal resistance evaporation method was used to coat a UV filter for disinfection. The resistance evaporation current was 88A. The first layer was lanthanum fluoride, and the second layer was magnesium fluoride. Four layers were coated in sequence, and then the temperature was kept for 20 minutes, and finally cooled for 2.5 hours. (2) The anti-virus UV filter after coating is cleaned with an organic solvent, aged, and then cleaned with an organic solvent again and stored in a vacuum.

7. The method for preparing a virus-killing ultraviolet filter according to claim 6, characterized in that: The vacuum degree of step (1) is 3×10 -3 Pa.

8. The method for preparing a virus-killing ultraviolet filter according to claim 6, characterized in that: The thickness of each coating layer in step (1) is 10-90 nm, and the film material of each coating layer contains 10% silver fluoride.

9. The method for preparing a virus-killing ultraviolet filter according to claim 6, characterized in that: The organic solvent in step (2) is ethanol.

10. The method for preparing a virus-killing ultraviolet filter according to claim 6, characterized in that: The aging process conditions of step (2) are: humidity of 85%, temperature of 85°C, and time of 50h.

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