CN116515217A - Flexible filter film for absorbing harmful ultraviolet light and preparation method thereof - Google Patents

Abstract

The invention provides a flexible filter film for absorbing harmful ultraviolet light, which has strong absorption near 257nm and high transmittance near 222nm. The flexible filter film includes an absorbing material and a film-forming material, The absorbing material includes base material, and the film-forming material is perfluoroplastic. The invention also provides a preparation method of the flexible filter film for absorbing harmful ultraviolet light. The flexible filter film provided by the invention is attached to the krypton chloride excimer lamp tube, which can make the krypton chloride excimer lamp a short-wave ultraviolet light source with high efficiency, low cost and large irradiation range, which greatly improves the krypton chloride excimer lamp. The scope of application and commercial value of molecular lamps.

Description

A flexible filter film for absorbing harmful ultraviolet light and its preparation method

This invention patent application is a divisional case with an application date of October 25, 2022 and an application number of CN202211313416.X Apply.

technical field

The invention belongs to the technical field of light-absorbing materials, and in particular relates to a flexible filter film for absorbing harmful ultraviolet light and a preparation method thereof.

Background technique

A large amount of experimental evidence has confirmed that short-wave ultraviolet light near 222nm is safe for the human body, but the lack of pure short-wave ultraviolet light source has always been the bottleneck in the field of human antivirus for short-wave ultraviolet light.

For more than a decade, short-wave UV LEDs have not made significant progress. Currently the most promising short-wave UV lamp source (UV light around 222nm) is the krypton chloride excimer lamp. Since the krypton chloride excimer lamp is a gas discharge lamp, in addition to ultraviolet light near 222nm, there is also a part of long-wavelength ultraviolet light. There has been a lot of evidence that these long-wavelength ultraviolet light is harmful to the human body, and the degree of harm depends on Irradiation intensity and dose.

To make the krypton chloride excimer lamp a safe lamp for human irradiation, it is necessary to filter the harmful light. With the traditional filter technology, only short-wave ultraviolet light source (222nm) with low efficiency, high cost and small irradiation range can be obtained, and its commercial value is very limited.

The traditional band-pass filter (film), or narrow-band filter, its filtering principle is the principle of light interference, therefore, the filter is mainly used in the case of quasi-parallel light, that is, to filter ultraviolet light at a single angle In order to effectively filter out harmful light.

However, the light emitted by the krypton chloride excimer lamp is multi-spectral, the spatial distribution of the luminous area is wide, and the angle of the light beam is a large angle. Therefore, using the above filter to filter out the light emitted by the krypton chloride excimer lamp not only The efficiency is low, and harmful light cannot be filtered out. Therefore, the safety of the human body cannot be guaranteed.

In the prior art, Interstellar Light (Shanghai) Industrial Co., Ltd. discloses a broad-spectrum killing and disinfection system, which uses a hundred layers of nano-optical interference coating (that is, filters light by interference method) to carry out harmful ultraviolet light of excimer lamps. Filtering, hoping to obtain pure and harmless 222nm ultraviolet rays, because the strong reflection of light incident at a large angle on the filter is not considered, so that only the light at a small space angle near the normal of the vertical filter can pass through, so , this filtering method is difficult to achieve large-scale killing. At the same time, because the ultraviolet light incident on the filter has not been effectively collimated, the filtered ultraviolet light still retains strong harmful light, which is difficult to ensure safety. and effectiveness.

In order to use this filter to obtain pure ultraviolet light, it must go through a complex light processing device. For example, the laboratory uses this light source for in-person killing experiments, and can use the blocking method to change the wide light source into a small light source. Then through collimation processing, a single angle of light is obtained, and then filtered with this filter. This method has the disadvantage of low utilization rate of light energy.

U.S. Patent Publication US20200234941A1 discloses an ultraviolet sterilizing device. In order to eliminate the additional harmful light emitted by the krypton chloride excimer lamp when ultraviolet light is used to sterilize the skin (hand), it adopts a very complicated filter device. The output light is collimated light, and then the 222nm interference filter is used to filter out the additional harmful light, but the structure of the ultraviolet sterilizer is complex, the light loss is large, and due to the difficulty of collimation, it can only be used for a small area. antivirus.

In order to make full use of the 222nm ultraviolet light emitted by the krypton chloride excimer lamp to achieve high-efficiency and large-scale antivirus, the Chinese patent publication CN202111295083.8 discloses that the harmful light in the excimer light is filtered out with an absorption filter, thereby ensuring radiation. According to the safety of the human body, this avoids the problem of poor wide-angle filtering effect of interference filters, but this absorption filter scheme also has the following problems in filtering:

1. Since there are very few materials that pass through deep ultraviolet light, the light transmission requirements of this filter are the same as those of the interference-type bandpass filter. It requires the filter to absorb all ultraviolet light above 235nm, and it must The light has a high transmittance. For broadband absorption, the absorbing material is required to have multiple absorption peaks, or multiple absorption groups. Materials with such absorption groups generally have higher terminal absorption near 222nm (some ultraviolet absorption peaks appear below 200nm) , so when detecting, you will see the phenomenon that the absorption spectrum shifts upward at 190-200nm, which is actually the absorption peak below 200nm is close to the end of the long-wave direction, so it is called terminal absorption.), therefore, it is difficult to ensure alignment The filter efficiency of the molecular light source.

2. This absorption filter is still in the form of a traditional filter. It is made of a flat plate or a combination of flat plates. Since the excimer is ultraviolet light with a wide spatial range and a wide emission angle, but this light is irradiated on the flat plate, For a small angle (the angle with the normal direction of the plate is small), the light transmittance is high, but for the incident light at a large angle, the light incident on the plate is almost completely reflected, and the deep ultraviolet is easily absorbed by the surrounding substances. This not only results in a low light energy utilization rate of the light source, but also makes the spatial irradiation area of this light small due to the large-angle light being reflected by the plate, and the light uniformity is poor, and safety is difficult to guarantee. The killing effect is not ideal.

Based on this, the present invention is proposed.

Contents of the invention

Aiming at the problems in the prior art, the inventor has carried out careful research and analysis on this. Obviously, it is necessary to use a filter to filter the excimer light source with a wide spatial range and a wide angle of light, while retaining a large spatial range and a wide angle. For the lighting characteristics of the light source, the best method is to use a flexible filter film or an absorption filter element that is compatible with the luminous tube. At least the direction of illumination is conformal, rather than using a flat filter. Since the krypton chloride excimer light source mainly emits 222nm deep ultraviolet light, there are also other wavelengths of ultraviolet light. They actually come from the transition of other energy levels formed by the mixed gas in the light during the discharge process, mainly from three Energy levels, as shown in Figure 1.

For the first peak, its peak wavelength is about 235nm. Due to the short wavelength, it has poor penetrating ability in organisms, and the skin epidermis and tear film layer basically block the light it emits. Therefore, it only needs to be filtered slightly; for 325nm Due to the long wavelength of ultraviolet light, the damage to organisms is not achieved through DNA damage, but through other mechanisms. Considering that the human body itself has the ability to repair, the radiation dose required to cause obvious damage to the human body is very high. High, and the 325nm and 235nm light energy emitted by the excimer lamp account for a small proportion of the light energy emitted by the entire lamp. In the case of killing people, the radiation intensity cannot be very high, so no special deal with.

Among the ultraviolet light emitted by the excimer lamp, the 257nm ultraviolet light is the most harmful to humans. According to the IEC62471 standard, the 257nm UVC radiation must be below 0.2μW/c㎡ to ensure long-term exposure safety, and the irradiance of short-term exposure to UVC radiation should not exceed 1.7μW/c㎡. WS/T 367-2012 "Technical Specifications for Disinfection in Medical Institutions", "Technical Specifications for Hospital Disinfection" in 2009, GB19258-2003 for ultraviolet germicidal lamps and other relevant standards have related requirements for the power intensity and detection of ultraviolet germicidal lamps. For the current commercial 222nm excimer lamps, in order to achieve disinfection, the light intensity of new lamps should be greater than 90μW/c㎡, the light intensity of old lamps needs to reach 70μW/c㎡, and when the light intensity is lower than 40μW/c㎡, it can reach No disinfection effect. Among the ultraviolet light emitted by the current 222nm excimer, the light intensity at 257nm on the surface reaches about 1.6% of the total light intensity. At 257nm, it reaches 1.12μW/c㎡. Even if it reaches 0.64μW/c㎡ for 40μW/c㎡, it is still far beyond the safe value of 0.2μW/c㎡. Therefore, in the effective antivirus area that meets the requirements , the crowd can only be exposed to this light for a short time. In order to achieve safe and effective antivirus, it is necessary to filter out the 257nm ultraviolet light to achieve safe irradiation for human disinfection.

From the above analysis, it can be seen that for excimer light, it is only necessary to absorb the ultraviolet light near 257nm ultraviolet light to ensure the safety of the human body. Such an optical filter has higher requirements for absorbing materials than bandpass filters. Much simpler, thereby reducing the design requirements of the absorbent material. Absorption requirements for absorbent materials are shown in Figure 2.

Those skilled in the art know that many materials are soft to a certain extent, easy to bend, and easy to stick on the surface of the lamp tube. Among them, plastic is a good choice, and it can absorb the selected material through conventional plastic processing technology. The material is mixed into the plastic film-forming material to form a flexible soft film, which is pasted on the surface of the lamp tube.

Since DUV belongs to short-wave UV with short wavelength and high photon energy, it will degrade many plastics. In order to ensure flexibility and tolerance, it is the best choice to find plastics that are not easy to degrade to make optical filters. Among them, fluorine-containing plastics are very A good film-forming material not only has a strong ability to resist ultraviolet light degradation, but also has a very mature technology of modifying materials by doping.

In order to ensure the flexibility and tolerance of the filter film, the film-forming material is preferably a perfluorinated material; at the same time, in order to ensure the short-wave ultraviolet transmission of 222nm, the film-forming material is preferably an amorphous perfluororesin.

Among the perfluorinated materials, perfluorinated materials that are transparent to deep ultraviolet rays are generally amorphous plastics, which are formed by copolymerization or homopolymerization of different plastic monomers.

At present, there are many transparent perfluorinated materials commercially available, such as DuPont's TeflonAF series, such as AF1600, which have good transparency to deep ultraviolet rays and are also very stable under ultraviolet light irradiation, and can be used as film-forming materials for films. The selected absorbing material can be doped into this plastic by appropriate process to form a flexible filter film completed according to the plastic processing method.

For example, commercial Teflon AF solution is used, which is dissolved in Made of Teflon AF amorphous fluoropolymer in FC-40, add an appropriate amount of nano-powder of selective absorption materials to the solution, shake or process in ultrasonic or other methods, so that the nanoparticles are fully dissolved in the solution, and then pass Form a thin layer on the glass substrate by spraying, spinning, brushing, dipping, etc., then heat and bake, and take off the transparent absorbing film from the glass substrate after cooling to obtain a flexible filter film.

For ultraviolet disinfecting, the scattered light emitted from the filter can not only disinfect the virus, but also overcome the blocking effect when the direct light encounters obstacles. Although the UV transparency of some perfluorinated materials is not ideal, the UV absorption ability of this material is very weak. Therefore, perfluorinated materials with less than ideal transparency can also be used as film-forming materials to reduce costs.

As for the choice of absorbent material, it needs to be considered that it has a synergistic effect with the performance of the film-forming material. For example, when adding UV-absorbing substances to the film-forming material, if the size of the absorbing particles is too large, the dispersion will not be good, and strong scattered light will be generated when incident on the particles, although forward scattered light is beneficial to killing Yes, but the backscattered light may spread to other places and be lost. Therefore, in order to ensure the effective transmission of 222nm light, the particle size of the absorbing material should not be too large, which can be 1 to 4 times that of 222nm. Of course, the absorption The particle size is better than 222nm, preferably less than half wavelength or even 1/4 wavelength, but considering that the smaller the scattering particles, the more difficult the process is, the particle range should be within the range of 50-800nm, preferably 80-200nm .

The absorbing material with a particle size of 50-800nm is obtained by mixing the commercially available absorbing material with deionized water at a mass ratio of 1:10-200, and then stirring under heating for 1-10 hours.

In order to reduce the 222nm light scattering loss caused by the addition, it is required that the light refractive index of the absorbing material should be as consistent as possible with the film-forming material. Therefore, organic absorbing materials can be considered; at the same time, the particles of the absorbing material should be small and uniformly dispersed in the film-forming material. In the material; considering that many absorbing materials are mixed into the solvent to produce strong absorption at the short-wave end, after adding the absorbing material, it is necessary to avoid strong absorption at 222nm. The inventors have found that the absorbent materials that can meet the several conditions listed above are guanidinium-based materials or base-based materials.

The inventors have found through experiments that, in addition to preparing flexible filter films by spraying, they can also use perfluoroplastic monomers and absorbing materials to grind, and then make filter films by calendering or extrusion.

It is also possible to dope the absorbing material into the perfluoroplastic through a suitable process such as spinning or immersing to make a filter film.

In order to ensure softness and transmittance at 222nm, the thickness of this filter film should be between 0.5-1000 microns.

Based on the above considerations, the present invention provides a flexible filter film for absorbing harmful ultraviolet light and a preparation method thereof. The flexible filter film of the present invention is a flexible and resistant to short-wave strong ultraviolet light, and has a high A thin film with a transmittance of 85% and a transmittance lower than 80% at 257nm can make the krypton chloride excimer lamp source a short-wave ultraviolet light source with high efficiency, low cost, and large irradiation range. Ultraviolet light is widely used to provide technical guarantee in the occasion of human killing.

One set of technical solutions of the present invention is a flexible filter film for absorbing harmful ultraviolet light, which has strong absorption near 257nm and high transmittance near 222nm, and the flexible filter film includes absorbing material and a film-forming material, the absorbing material includes a guanidinium-based material or a base-based material, and the film-forming material is a perfluoroplastic.

Further, the guanidine salt material is guanidine isothiocyanate; the base material is one or more of adenine, adenosine, guanosine, deoxyadenosine, deoxyguanosine, and guanine kind. Adenine, Adenosine, Guanosine, Deoxyadenosine, Deoxyguanosine, Guanine, etc. have strong absorption near 257nm and at 222nm near high transmittance.

Further, the film-forming material is fully transparent amorphous perfluoroplastic.

Further, the thickness of the flexible filter film is between 0.5-1000 microns.

Further, the absorbing material is nano powder, and the weight ratio of the absorbing material in the flexible filter film is in the range of 1-15%, preferably 5%.

Another set of technical solutions of the present invention is a method for preparing a flexible filter film for absorbing harmful ultraviolet light, comprising the following steps:

S1: At room temperature, add 1-15% of the absorbing material nano-powder to the film-forming material solvent so that the two are evenly mixed;

S2: Spray the uniformly mixed mixture on the substrate to form a coating film;

S3: keeping the substrate with the coating film in an environment of 160 ° C ~ 240 ° C for 4 hours;

S4: cooling, and taking off the coating film from the substrate to obtain a flexible filter film.

Further, the particle size of the nano-powder of the absorbing material is 50-800nm.

Further, in step S1, the mixture is vibrated with an ultrasonic irradiation device with an intensity of 10-90 MPa, so as to increase the mixing speed of the absorbing material in the film-forming material solvent.

Another set of technical solutions of the present invention is a method for preparing a flexible filter film for absorbing harmful ultraviolet light, which involves grinding perfluoroplastic monomers and absorbing materials, and then making a flexible filter film by calendering or extrusion. light film.

Another set of technical proposals of the present invention is a method for preparing a flexible filter film for absorbing harmful ultraviolet light. The mixture of the film-forming material and the absorbing material is processed into a thin film by using a spinning or immersion process to obtain a flexible filter film. filter film.

The present invention has the advantage over prior art that:

1. There is no need to convert the light emitted by the krypton chloride excimer lamp into quasi-flat light, which overcomes the problems of low efficiency and inability to filter out harmful light in traditional band-pass filters/films or narrow-band filters;

2. There is no need to use complex filter devices to collimate ultraviolet light, and there is no problem of large light loss and small anti-virus range;

3. The light absorption ability at 257nm is much greater than that at 222nm, which improves the filtering efficiency;

4. A flexible filter film is used to attach to the krypton chloride excimer lamp tube, which avoids the situation that the light at a large angle will be reflected by the plate, and can ensure a large irradiation space area, wide-angle illumination, and good uniformity of light.

5. A flexible filter film is used to attach the krypton chloride excimer lamp tube, which can make the krypton chloride excimer lamp a short-wave ultraviolet light source with high efficiency, low cost and large irradiation range, which greatly improves the krypton chloride excimer lamp. The scope of application and commercial value of the lamp.

Description of drawings

These and/or other aspects and advantages of the present invention will become clearer and easier to understand from the following detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, wherein:

Fig. 1 is the light component analysis diagram of the krypton chloride excimer light source mentioned in the summary of the invention;

Fig. 2 is the transmittance requirement curve of the optical filter mentioned in the summary of the invention;

Fig. 3 is the ultraviolet absorption curve of the flexible filter film obtained in Example 1 of the present invention;

Fig. 4 is the transmittance curve of the flexible film that embodiment 1 gains;

Fig. 5 is the ultraviolet absorption curve of the flexible filter film obtained in Example 2 of the present invention;

Fig. 6 is the ultraviolet light absorption curve of the flexible filter film obtained in Example 3 of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

It should be noted that, in the present invention, "in-person disinfecting" means that there are people in ordinary clothes who do not need special protection to carry out disinfection in the on-site environment.

Example 1

A preparation method for a flexible filter film for absorbing harmful ultraviolet light is as follows: first, at normal temperature, 10 g of pure guanidine isothiocyanate is dissolved in 30 ml of deionized water, and after it is completely dissolved, the undissolved substances are filtered out, and then Pour it into 100ml of perfluorinated solvent, heat it to 80°C, and make it into a nano-water-in-oil emulsion by means of high-pressure homogenization, high-speed stirring or strong ultrasonic treatment, and then pour them into an amorphous fluoropolymer solution (AF1601 ), then fully mix it by stirring, and then apply the mixed solution on a clean flat glass by spraying means to form a thin layer with a thickness of about 2-5 μm, and then send it into a high-temperature baking oven to slowly Heating to above the solvent removal temperature (temperature is 160° C.), and keeping the temperature at a constant temperature for 4 hours, then slowly cooling to normal temperature, and then peeling off the formed film layer from the glass to obtain a flexible filter film with a thickness of about 2 microns. After testing, the ultraviolet light absorption curve of the film is shown in Figure 3.

As can be seen from Figure 3, the absorption curve of the flexible filter film obtained in this embodiment has an absorption rate of 0.04 at 222, an absorption rate of 0.087 at 235nm, and an absorption rate of 0.168 at 257nm. Obviously, the absorption rate of 257nm is 4.2 times that of 222nm , 235nm absorption rate is more than 2 times of 222nm absorption rate.

It can be seen from FIG. 4 that the transmittance of the flexible filter film obtained in this embodiment is 88% at 222nm, and 75% at 257nm. In order to ensure the effectiveness of human disinfection, the higher the transmittance at 222nm, the better. However, there are few materials with high transparency and stability to ultraviolet radiation at 222nm. After adding materials, due to residual absorption and scattering, it will inevitably decrease. The transmittance at 222nm, however, although the forward scattering caused by the addition of absorbing particles reduces the transmittance, this part of the light is also effective for sterilization, so the transmittance of 88% is very good. In order to ensure the safety of disinfecting people, the transmittance of 257nm should be as low as possible under the condition of high transmittance of 222nm. The transmittance difference of the filter film at these two wavelengths is the quality of the filter film. The key indicator, the greater the transmittance difference at the two wavelengths, the better. Our preliminary test results here have reached a transmittance difference of 13%. If the influence of scattering is considered (because the wavelength of 222nm is shorter and the scattering is larger), the ratio of the non-scattering state can exceed 15%.

Of course, it is also possible to directly dissolve 30ml of guanidine isothiocyanate aqueous solution and 200ml of perfluorinated solvent into the amorphous fluoropolymer (AF1601) solution, and make nano-oil by means of high-pressure homogenization, high-speed stirring or strong ultrasonic treatment. Water-in-emulsion (treatment for about 6 hours), and then spray the mixed solution on a clean flat glass to form a thin layer of about 2-5μm thick, and then send it into a high-temperature oven for slow heating Warm to above the solvent removal temperature (temperature is 160°C), and keep at constant temperature for 4 hours, then slowly cool to room temperature, and then peel off the formed film from the flat glass, and an absorption curve similar to that shown in Figure 3 can also be obtained.

Example 2

A preparation method of a flexible filter film for absorbing harmful ultraviolet light is as follows: firstly, at a temperature of 80° C., 1 g of pure adenine is dissolved in 50 ml of deionized water, and after it is completely dissolved, the undissolved substances are filtered out, and then, Pour it into 100ml of perfluorinated solvent at a temperature of 90°C, process it into a nano-water-in-oil emulsion by means of high-pressure homogenization, high-speed stirring or strong ultrasound, and then pour them into an amorphous fluoropolymer solution (AF2400 ), and then fully mix it by stirring, and then apply the mixed solution on a clean flat glass by spraying means to form a thin layer with a thickness of about 2-5 μm, and then send it into a high-temperature baking furnace to slowly add Warm to above the solvent removal temperature (the temperature is 240° C.), and keep at a constant temperature for 4 hours, then slowly cool to normal temperature, and then peel off the formed film layer from the flat glass to obtain a flexible filter film with a thickness of about 2 microns. The UV absorption curve of the film is shown in Fig. 4 .

As can be seen from Figure 4, the absorption curve of the flexible filter film obtained in this embodiment has an absorption rate of 0.021 at 222nm, an absorption rate of 0.064 at 235nm, and an absorption rate of 0.150 at 257nm. Obviously, the absorption rate of 257nm is 7 times that of 222nm , The absorption rate at 235nm is more than three times that at 222nm.

Example 3

A preparation method for a flexible filter film for absorbing harmful ultraviolet light is as follows: first, at a temperature of 80°C, dissolve 10g of pure adenine into 500ml of water (deionized water), and filter out undissolved substances after it is completely dissolved , Then, mix 1Kg of amorphous perfluorinated material AF2400 with adenine aqueous solution, mix and grind it into fine powder in a ball mill, and then extrude it into a flexible filter film according to the AF2400 calendering process. The UV absorption curve of the film is shown in FIG. 5 .

As can be seen from Fig. 5, the absorption rate of the flexible filter film obtained in this embodiment is 0.057 at 222nm, 0.072 at 235nm, and 0.150 at 257nm. Obviously, the absorption rate at 257nm is 2.6 times that of 222nm , the absorption rate at 235nm is more than 1.3 times that at 222nm.

Having described various embodiments of the present invention, the foregoing description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and alterations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (10)

1. A flexible filter film for absorbing harmful ultraviolet light, which has strong absorption near 257nm and high transmittance near 222nm, is characterized in that the flexible filter film includes absorbing material and film-forming material, the absorbing material includes base material, and the film-forming material is perfluoroplastic. 2. The flexible filter film for absorbing harmful ultraviolet light according to claim 1, wherein the base material is adenine, adenosine, guanosine, deoxyadenosine, deoxyguanosine , one or more of guanine. 3. The flexible filter film for absorbing harmful ultraviolet light according to claim 1, characterized in that, the film-forming material is transparent amorphous perfluoroplastic. 4. The flexible filter film for absorbing harmful ultraviolet light according to claim 1, characterized in that the thickness of the flexible filter film is between 0.5-1000 microns. 5. The flexible filter film for absorbing harmful ultraviolet light according to claim 1, characterized in that, the absorbing material is a nano-powder, and the weight ratio of the absorbing material in the flexible filter film is 1-15% within range. 6 . The flexible filter film for absorbing harmful ultraviolet light according to claim 5 , wherein the absorbing material accounts for 5% by weight of the flexible filter film. 7. The method for preparing a flexible filter film for absorbing harmful ultraviolet light according to any one of claims 1-6, characterized in that, comprising the steps of: S1: At room temperature, add 1-15% of the absorbing material nano-powder to the film-forming material solvent so that the two are evenly mixed; S2: Spray the uniformly mixed mixture on the substrate to form a coating film; S3: keeping the substrate with the coating film in an environment of 160 ° C ~ 240 ° C for 4 hours; S4: cooling, and taking off the coating film from the substrate to obtain a flexible filter film. 8. The preparation method according to claim 7, characterized in that, in step S1, the mixture is vibrated by an ultrasonic irradiation device with an intensity of 10-90 MPa, so as to increase the concentration of the absorbing material in the film-forming material solvent. mixing speed. 9. The method for preparing a flexible filter film for absorbing harmful ultraviolet light according to any one of claims 1-6, wherein the perfluoroplastic monomer is ground with the absorbing material, and then pressed or extruded The process is made into a flexible filter film. 10. The method for preparing a flexible filter film for absorbing harmful ultraviolet light according to any one of claims 1-6, wherein the mixture of the film-forming material and the absorbing material is processed and formed by a process of rotation or immersion film to obtain a flexible filter film.