Photochromic film with multiple light responses and preparation method and application thereof

Abstract

This invention discloses a photochromic thin film with multiple photoresponses, its preparation method, and its applications, belonging to the field of organic functional materials technology. The raw materials for the photochromic thin film with multiple photoresponses include: a photosensitive monomer, a photoacid monomer, and Dow Corning DC 184; the structural formula of the photosensitive monomer is [insert structural formula here]; wherein, R... 1 ~R 7 Each is independently selected from one of -H, -CH3, -CF3, -CCl3, -CBr3, -N(Me)2, -CN, -OMe, R 8 Selected from -(CH2) n CH=CH2、-(CH2OCH2) n CH=CH2、-(CH2) n One of OCOC(CH3)=CH2, where n is 1~5. This invention provides a photochromic thin film with multiple photoresponses, which can achieve multi-dimensional information storage by controlling the light wavelength and irradiation time, significantly improving information storage capacity and encryption complexity.

Description

Technical Field

[0001] This invention belongs to the field of organic functional materials technology, specifically relating to a photochromic thin film with multiple photoresponses, its preparation method, and its application. Background Technology

[0002] Responsive color-changing materials can change color under the influence of external fields (heat, force, light, electricity, magnetism, etc.), and have broad application prospects in optical anti-counterfeiting, stress sensing, information storage, and material damage detection. Among them, light stimulation has become an ideal signal input method for anti-counterfeiting systems due to its non-contact precise control, high spatiotemporal resolution, and multi-dimensional parameter programmability. By adjusting parameters such as wavelength, intensity, and spatial distribution of the light field, high-density optical information encryption and dynamic anti-counterfeiting can be achieved.

[0003] Given the advantages of light stimulation, photoresponsive color-changing materials have become an excellent choice for encryption and anti-counterfeiting. Although numerous studies have been conducted on encryption using photoresponsive polymers, the development of these materials still faces many limitations, such as single wavelength response, poor operability, excessively long or short read times, and the ability to provide only a single encryption mode. Therefore, it is necessary to develop photoresponsive materials with multi-dimensional encryption capabilities and suitable read times to overcome these challenges. Summary of the Invention

[0004] To address the problems mentioned in the background section, the present invention aims to provide a photochromic thin film with multiple photoresponses, its preparation method, and its applications. The core function of this photochromic thin film with multiple photoresponses relies on the synergistic effect of photosensitive monomers and photoacid-releasing monomers, enabling precise response to multiple wavelengths of light: under red and green light irradiation, the photosensitive monomers in the film undergo a reversible Z / E configuration transition in the neutral state; under ultraviolet light irradiation, the photoacid-releasing monomers in the film are excited and release proton hydrogen, which specifically binds to the nitrogen atom of the dimethylamino group in the photosensitive monomer, thereby driving the photosensitive monomer from the neutral state to the proton state. By precisely controlling the light wavelength and irradiation time, and combining it with mask exposure technology, multiple isomerization can be directionally induced in the target area of ​​the film, thereby enabling multi-dimensional information storage applications. The aforementioned multiple isomerization process of the photosensitive monomers allows the film to produce richer reversible color changes, providing core support for differentiated identification and dynamic control in information storage, optical encryption, and anti-counterfeiting, further enhancing the flexibility and security of information storage.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: On the one hand, the present invention provides a photochromic film with multiple photoresponses, wherein the raw materials of the photochromic film with multiple photoresponses include: photosensitive monomer, photoacid monomer, and Dow Corning DC 184.

[0006] The structural formula of the photosensitive monomer is shown in formula (1): Equation (1);

[0007] Among them, R 1 ~R 7 Each is independently selected from one of -H, -CH3, -CF3, -CCl3, -CBr3, -N(Me)2, -CN, -OMe, R 8 Selected from -(CH2) n CH=CH2、-(CH2OCH2) n CH=CH2、-(CH2) n One of OCOC(CH3)=CH2, where n is 1~5.

[0008] Furthermore, the method for preparing the photosensitive monomer includes the following steps:

[0009] (1) Under a nitrogen atmosphere, Sodium hydride was dissolved in an organic solvent and stirred to react, yielding a precursor solution.

[0010] (2) Add Br-R to the precursor solution 8 An alkylation reaction was carried out, and after the reaction was completed, a saturated ammonium chloride solution was added to quench the reaction. The organic phase was then separated and collected. The organic phase was washed, dried, and concentrated to obtain the crude product.

[0011] (3) The crude product is purified by column chromatography and then recrystallized to obtain the photosensitive monomer.

[0012] Further, the steps described in step (1) The molar ratio of sodium hydride to sodium hydride is 1:(1.5~10).

[0013] The organic solvent mentioned in step (1) includes N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide or N-methylpyrrolidone;

[0014] The temperature of the reaction in step (1) is 0°C and the reaction time is 15~60 min.

[0015] Furthermore, the aforementioned and Br-R 8 The molar ratio is 1:(1~10).

[0016] Furthermore, the alkylation reaction in step (2) is carried out at room temperature;

[0017] The washing process in step (2) specifically involves washing the organic phase sequentially with a saturated sodium bicarbonate solution, deionized water, and a saturated sodium chloride solution.

[0018] The drying in step (2) is carried out using an anhydrous desiccant, which includes anhydrous sodium sulfate or anhydrous magnesium sulfate;

[0019] The concentration described in step (2) is vacuum concentration.

[0020] Further, in step (3), the crude product is dissolved in dichloromethane for column chromatography; the eluent for the column chromatography is a mixture of petroleum ether and ethyl acetate;

[0021] In step (3), a methanol / water system is used for recrystallization.

[0022] Furthermore, the photo-emitting acid monomer can release protonated hydrogen in response to ultraviolet light.

[0023] Furthermore, the photoluminescent acid monomer is selected from one of haloaryl ester photoluminescent acid monomers, sulfonate photoluminescent acid monomers, and sulfonyloxyoxime photoluminescent acid monomers, preferably haloaryl ester photoluminescent acid monomers.

[0024] Furthermore, the general structural formula of the haloaryl ester photoluminescent acid monomer is Ar-O-CO-R. 9 Ar is selected from halogenated aryl groups, and R... 9 It is selected from one of C1-C12 saturated alkyl, C1-C12 haloalkyl, C1-C12 alkyl containing unsaturated bonds, C6-C12 aryl, C6-C12 haloaryl, and C1-C12 substituted alkyl containing heteroatoms or functional groups;

[0025] And / or, the general structural formula of the sulfonate photoluminescent acid monomer is R 10 -SO3 - M + (where R) 10 It is an organic hydrophobic group, SO3 - M is a sulfonate anion. + (is a cation), where R 10 Selected from one of C1-C12 alkyl, C6-C18 aryl, C1-C12 haloalkyl, and C6-C18 haloaryl, its core function is to enhance the compatibility of the monomer with the polydimethylsiloxane system and toluene solvent, and to prevent phase separation. + Selected from H + Na + K + One of the organic ammonium ions;

[0026] And / or, the general structural formula of the sulfonyloxyoxime photoluminescent acid monomer is R 11 -SO2-ON=(R 12 (R) 13 (where R is in the formula) 11 R is a sulfonyl substituent.12 R 13 (for oxime substituents), where R 11 Selected from one of C1-C12 alkyl, C6-C18 aryl, C1-C12 haloalkyl, and C6-C18 haloaryl, electron-withdrawing substituents can lower the photolysis energy barrier and improve response sensitivity. 12 R 13 Each is independently selected from -H, C1-C10 alkyl, C6-C18 aryl, -CN, COOR 14 One of them, R 14 It is a C1-C6 alkyl group.

[0027] Furthermore, the Ar selected from halogenated aryl groups includes 2,6-Dichlorophenyl, 2,4-Dibromophenyl, 2,6-Difluorophenyl, 2,4,6-Trichlorophenyl, 4-Chlorophenyl, 2-Bromonaphthyl;

[0028] The R 9 The selected C1-C12 saturated alkyl groups include methyl, ethyl, n-propyl, and isopropyl; the selected C1-C12 haloalkyl groups include trifluoromethyl, difluoromethyl, chloromethyl, and bromomethyl; the selected C1-C12 alkyl groups containing unsaturated bonds include vinyl, allyl, 3-butynyl, and 3-butenyl; the selected C6-C12 aryl groups include phenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, phenethyl, and naphthylmethyl; the selected C6-C12 haloaryl groups include 4-chlorophenyl, 2,4-dichlorophenyl, 4-fluorophenyl, and 4-bromophenyl; and the selected C1-C12 substituted alkyl groups containing heteroatoms or functional groups include methoxymethyl, ethoxyethyl, cyanomethyl, and trifluoromethoxymethyl.

[0029] The R 10 The selected C1-C12 alkyl groups include methyl, ethyl, propyl, tert-butyl, and dodecyl; the C6-C18 aryl groups include phenyl, 1-naphthyl, 2-naphthyl, 2-methylphenyl, 3-methylphenyl, and 4-methylphenyl; the C1-C12 haloalkyl groups include monofluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, and bromomethyl; the C6-C18 haloaryl groups include 2-fluorophenyl, 3-chlorophenyl, 3-fluorophenyl, 4-chlorophenyl, and 2-bromophenyl; the organic ammonium ions include tetraalkylammonium ions, pyridinium ions, and imidazolium ions, and the tetraalkylammonium ions include tetramethylammonium ions, tetrabutylammonium ions, tetraethylammonium ions, and tetra-n-propylammonium ions;

[0030] The R 11The selected C1-C12 alkyl groups include methyl, ethyl, n-propyl, and isobutyl; the C6-C18 aryl groups include phenyl, biphenyl, 2-methoxyphenyl, 3-methoxyphenyl, 4-methoxyphenyl, 1-naphthyl, 2-naphthyl, 2-methylphenyl, 3-methylphenyl, and 4-methylphenyl; the C1-C12 haloalkyl groups include fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, bromomethyl, and bromoethyl; and the C6-C18 haloaryl groups include 2-fluorophenyl, 2-bromophenyl, 4-iodophenyl, 4-fluorophenyl, 2-bromonaphthyl, 2,4-difluorophenyl, and 2,4,6-trichlorophenyl; the R 12 R 13 The selected C1-C10 alkyl groups include methyl, ethyl, n-propyl, n-butyl, isobutyl, and cyclohexyl; the C6-C18 aryl groups include phenyl, 2-methoxyphenyl, 3-methoxyphenyl, 4-methoxyphenyl, 2-methylphenyl, 3-methylphenyl, and 4-methylphenyl; the R 14 The selected C1-C6 alkyl groups include methyl, ethyl, n-propyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, and cyclohexyl.

[0031] Furthermore, Dow Corning DC 184 comprises a base component and a curing agent; the mass ratio of the base component to the curing agent is (5~10):1. This ratio range ensures complete curing of the photochromic film with multiple photoresponses, while also possessing good flexibility and stability.

[0032] Furthermore, the mass ratio of the photosensitive monomer to the photoacid monomer is 1:(15~30). This ratio range ensures that the proton hydrogen released by the photoacid monomer can sufficiently induce a configurational change in the photosensitive monomer, while avoiding film performance degradation caused by insufficient or excessive photoacid monomer. Specifically, this ratio ensures that the proton hydrogen released by the photoacid monomer can fully combine with the nitrogen atom of the dimethylamino group in the photosensitive monomer, thereby efficiently triggering the configurational change of the photosensitive monomer, while avoiding the impact of excessive or insufficient proton hydrogen on the photosensitivity performance.

[0033] Furthermore, the mass ratio of the photosensitive monomer to Dow Corning DC 184 is 1:(900~1200).

[0034] On the other hand, the present invention provides a method for preparing a photochromic thin film with multiple photoresponses as described above, comprising the following steps:

[0035] (1) Dissolve the photosensitive monomer and photoacid monomer in a solvent, and add the base components of Dow Corning DC 184 and the curing agent in sequence under continuous stirring to obtain a mixture;

[0036] (2) Stir the mixture described in step (1) for a period of time, then quickly transfer it to a mold and then cure it to obtain the photochromic film with multiple light responses.

[0037] Furthermore, the solvent mentioned in step (1) includes toluene. Toluene has the best solubility for both monomers, resulting in better uniformity of the prepared film.

[0038] Furthermore, the stirring rate in step (2) is 200~700 r / min, the stirring time is 5~10 min, and the stirring temperature is room temperature. These stirring parameters ensure that the raw materials are fully mixed to form a uniform and stable reaction mixture, avoiding any impact on the photoresponse performance of the film due to uneven mixing.

[0039] Furthermore, the curing temperature is 60~80℃, and the curing time is 10~15h. These curing parameters ensure complete solvent evaporation and complete film formation.

[0040] On the other hand, the present invention provides an application of the photochromic film with multiple photoresponses as described above or the photochromic film with multiple photoresponses prepared by any of the above-described preparation methods in information storage, optical encryption and anti-counterfeiting.

[0041] Furthermore, under red and green light irradiation, the photosensitive monomer in the photochromic film with multiple photoresponses undergoes a reversible Z / E configuration transition in the neutral state, accompanied by a corresponding color change. Under ultraviolet light irradiation, the photoacid monomer in the photochromic film with multiple photoresponses is excited to release proton hydrogen. This proton hydrogen specifically binds to the nitrogen atom of the dimethylamino group in the photosensitive monomer, thereby causing the photosensitive monomer to undergo a configuration transition from the neutral state to the proton state, resulting in a significant color change in the photochromic film with multiple photoresponses. It possesses multiple photoresponse characteristics, and its response mechanism is precisely matched to the light wavelength.

[0042] With regard to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] (1) The photochromic thin film of the present invention possesses a clear and controllable multi-photoresponse characteristic. Its core mechanism lies in the fact that the photosensitive monomer can respond to light stimulation of specific wavelengths through different configurational transition paths: under red and green light irradiation, the photosensitive monomer undergoes Z / E configurational isomerization in the neutral state; while under ultraviolet light irradiation, the proton hydrogen released by the photoacid monomer specifically binds to the nitrogen atom of the dimethylamino group in the photosensitive monomer, driving it to undergo a configurational transition from the neutral state to the proton state. This multi-response mechanism is clear, the triggering path is independent and the response efficiency is high, effectively breaking through the technical limitation of existing photosensitive color-changing materials that can only achieve a single encryption mode. By adjusting parameters such as light wavelength and irradiation time, multi-dimensional information storage can be achieved, significantly improving the information storage capacity and encryption complexity. It can effectively solve the problem of high-capacity information storage that urgently needs to be solved in the current field of optical encryption materials, and provides a feasible technical path for improving the performance and expanding the practical application of optical encryption materials.

[0045] (2) By adjusting the light wavelength and irradiation time, combined with mask exposure technology, this invention can accurately induce the isomerization of the target area of ​​the thin film. It is easy to operate and the reading time is controllable, which solves the problems of single light response wavelength and unreasonable reading time in the existing system.

[0046] (3) The photochromic thin film with multiple photoresponses of the present invention has a simple preparation process, readily available raw materials, mild reaction conditions, and is easy to industrialize. When applied to the fields of encryption and anti-counterfeiting, it has high information security and is not easy to be cracked, and has broad application prospects. Attached Figure Description

[0047] Figure 1 The graph shows the change of storage modulus with temperature under dynamic thermomechanical analysis temperature scanning of the photochromic thin film with multiple photoresponses prepared in Example 1 of the present invention.

[0048] Figure 2 The graph shows the loss factor of the photochromic thin film with multiple photoresponses prepared in Example 1 of the present invention as a function of temperature under dynamic thermomechanical analysis temperature scanning.

[0049] Figure 3 This is a schematic diagram illustrating the application of the photochromic thin film with multiple photoresponses prepared in Example 1 of the present invention.

[0050] Figure 4 This is a schematic diagram illustrating the application of the photochromic thin film with multiple photoresponses prepared in Example 1 of the present invention. Detailed Implementation

[0051] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments, but the scope of protection and implementation of the present invention are not limited thereto.

[0052] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; the materials and reagents used are commercially available unless otherwise specified.

[0053] Example 1

[0054] Photochromic thin film with multiple photoresponses: raw materials include photosensitive monomer, photoacid monomer, and Dow Corning DC184; the photosensitive monomer is... Photoluminescent acid monomer is .

[0055] Preparation of photosensitive monomers: (1) (0.274 mmol) and sodium hydride (2.05 mmol) were added together to a 10 mL Schlenk tube. After removing the air by pumping out the air, nitrogen gas was introduced into the Schlenk tube. Under the nitrogen atmosphere, 3 mL of N,N-dimethylformamide was added, and the mixture was stirred at 0 °C for 15 min to obtain the precursor solution. (2) 4-bromo-1-butene (1.64 mmol) was added dropwise to the precursor solution. After the addition was complete, the mixture was transferred to room temperature and the reaction continued for 12 h. The reaction progress could be monitored by thin-layer chromatography (TLC, with petroleum ether: ethyl acetate = 3:1 as the developing solvent). After the raw materials had reacted completely, saturated ammonium chloride solution (10 mL) was added to quench the reaction, and then the aqueous phase and organic phase were separated. The aqueous phase was extracted with ethyl acetate (3×50mL) to extract the organic phase. The combined organic phases were washed successively with saturated sodium bicarbonate solution (3×100mL), deionized water (3×100mL), and saturated sodium chloride solution (3×100mL), and then dried with anhydrous magnesium sulfate. Finally, the solvent was removed by vacuum concentration to obtain the crude product. (3) The crude product was dissolved in dichloromethane (CH2Cl2), adsorbed onto silica gel powder, and purified by column chromatography (silica gel, eluent: petroleum ether: ethyl acetate = 100:0 → 75:25). After collecting the target component, it was recrystallized from methanol / water (MeOH / H2O) to obtain the photosensitive monomer. The product was a red fine powder with a yield of 70%.

[0056] Preparation of photochromic film with multiple photoresponses: (1) Place the photosensitive monomer (2.1 mg) and photoacid monomer (37 mg) in a 20 mL vial, add toluene (2 mL) to completely dissolve them, add the base component of Dow Corning DC 184 (2.0 g) while stirring continuously, and then add the curing agent of Dow Corning DC 184 (0.2 g) to obtain a red mixture. (2) Continue stirring the above red mixture at room temperature for 7 min (stirring rate of 700 r / min), and then quickly transfer it to a polytetrafluoroethylene (PTFE) mold. Place the mold in an oven and cure it at 60 °C for 12 h to finally obtain a photochromic film with multiple photoresponses, denoted as HI-DTPP-PDMS film.

[0057] Dynamic thermomechanical analysis (DMA) was performed on the photochromic thin film exhibiting multiple photoresponses, and the results are as follows: Figure 1 and Figure 2 As shown. According to Figure 1 It can be seen that the HI-DTPP-PDMS film has extremely high hardness (>1.8×10) at low temperatures. 5 (MPa), this property ensures the structural strength of the HI-DTPP-PDMS film; the HI-DTPP-PDMS film maintains a good rubbery state above room temperature, ensuring its flexibility. According to Figure 2 It can be seen that the glass transition temperature of HI-DTPP-PDMS film is approximately -50℃, exhibiting excellent low-temperature folding resistance and brittleness resistance.

[0058] Application of photochromic films with multiple photoresponses in encryption fields such as optical anti-counterfeiting and information storage (Figure 1) Figure 3 As shown, the precise control process of its pattern "show-hide-reconstruct" is as follows:

[0059] (1) Pattern engraving (Z→E isomerization): Green light with a wavelength of 505nm is used in conjunction with a mask with a rabbit shape to irradiate the film for 3 minutes. The photosensitive monomer in the film undergoes neutral Z→E configuration isomerization, and the area not covered by the mask appears purple, thus engraving a clear purple rabbit pattern on the surface of the film.

[0060] (2) Pattern erasure (E→Z isomerization): If it is necessary to restore the initial state of the film, the entire film area is irradiated with red light with a wavelength of 625nm for 80min. The photosensitive monomer in the film undergoes E→Z reverse isomerization, the purple rabbit pattern disappears, and the film is restored to the initial uniform red state.

[0061] (3) Pattern Reconstruction (Neutral State → Proton State Transition): To achieve secondary encryption of the pattern, ultraviolet light with a wavelength of 310 nm is used, along with the same rabbit mask, to irradiate the film for 5 minutes. At this time, the photoacid monomer in the film is excited by ultraviolet light and releases proton hydrogen. This proton hydrogen specifically binds to the nitrogen atom of the dimethylamino group in the photosensitive monomer, driving the photosensitive monomer to undergo a configurational transition from a neutral state to a proton state. Ultimately, the film surface exhibits a light-colored rabbit pattern with lower contrast, thus achieving secondary reconstruction of information. The above operation, through the synergistic effect of controlling the light wavelength, irradiation time, and mask, utilizes the dual photoresponse mechanism of the film's "Z / E isomerization" and "neutral state-proton state transition" to achieve multi-dimensional encryption and dynamic control of information, verifying the feasibility of the film of this invention in high-security anti-counterfeiting scenarios.

[0062] Applications of photochromic films with multiple photoresponses in encryption fields such as optical anti-counterfeiting and information storage (see diagram 2) Figure 4 As shown, the precise control process for the pattern's "show-hide-negative shape show" is as follows:

[0063] (1) Claw pattern engraving (Z→E isomerization): Green light with a wavelength of 505nm is used in conjunction with a mask with a double claw shape to irradiate the film for 3 minutes. The photosensitive monomer in the masked area (i.e. the claw pattern area) of the film undergoes neutral Z→E configuration isomerization, and the color of this area changes from the initial red to purple, thus engraving a clear double claw pattern on the surface of the film.

[0064] (2) Gradient erasure and negative display of the pattern (neutral state → proton state transition and secondary response): The film was irradiated stepwise with ultraviolet light of wavelength 310nm and the same double claw mask. After the first irradiation for 1 minute, the color of the claw pattern area was significantly lighter than the initial purple. As the irradiation time was extended, the pattern continued to fade. After a cumulative irradiation of 310nm for 3 minutes, the claw pattern completely disappeared and the film returned to a uniform red. Subsequently, without a mask, the entire thin film was irradiated with 505nm green light for 3 minutes, and the claw pattern reappeared in a negative form. The core mechanism is that in the claw region irradiated with a 310nm mask, the photoacid monomer is excited and releases protons. These protons specifically bind to the nitrogen atom of the dimethylamino group in the photosensitive monomer, driving the photosensitive monomer to irreversibly transition from a neutral state to a proton state. This configuration no longer responds to 505nm green light. In the background region not irradiated with 310nm light, the photosensitive monomer remains in a neutral state and undergoes Z→E isomerization under 505nm green light irradiation, changing from red to purple. Ultimately, the background region becomes purple, while the claw region remains red, achieving the negative manifestation of the claw pattern and verifying the precise controllability of the thin film's multiple photoresponses.

[0065] The above description is only a specific embodiment of the present invention and not all embodiments. Any equivalent modifications made by those skilled in the art to the technical solutions of the present invention by reading the present invention specification shall be covered by the claims of the present invention.

Claims

1. A photochromic thin film with multiple photoresponses, characterized in that, The raw materials of the photochromic film with multiple photoresponses include: photosensitive monomer, photoacid monomer, and Dow Corning DC 184; The structural formula of the photosensitive monomer is shown in formula (1): Equation (1); Among them, R 1 ~R 7 Each is independently selected from one of -H, -CH3, -CF3, -CCl3, -CBr3, -N(Me)2, -CN, -OMe, R 8 Selected from -(CH2) n CH=CH2、-(CH2OCH2) n CH=CH2、-(CH2) n One of OCOC(CH3)=CH2, where n is 1~5; The mass ratio of the photosensitive monomer to the photoacid monomer is 1:(15~30). The photo-emitting acid monomer is selected from haloaryl ester photo-emitting acid monomers; The general structural formula of the haloaryl ester photoluminescent acid monomer is Ar-O-CO-R. 9 Ar is selected from R 9 Selected from C1-C12 alkyl groups containing unsaturated bonds; The C1-C12 alkyl groups containing unsaturated bonds include vinyl, allyl, 3-butynyl, and 3-butenyl.

2. The photochromic thin film with multiple photoresponses according to claim 1, characterized in that, The Dow Corning DC184 comprises a base component and a curing agent; the mass ratio of the base component to the curing agent is (5~10):

1.

3. The photochromic thin film with multiple photoresponses according to claim 1, characterized in that, The mass ratio of the photosensitive monomer to Dow Corning DC 184 is 1:(900~1200).

4. The method for preparing a photochromic thin film with multiple photoresponses as described in any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Dissolve the photosensitive monomer and photoacid monomer in a solvent, and add the base components of Dow Corning DC 184 and the curing agent in sequence under continuous stirring to obtain a mixture; (2) Stir the mixture described in step (1) for a period of time, then quickly transfer it to a mold and then cure it to obtain the photochromic film with multiple light responses.

5. The preparation method according to claim 4, characterized in that, The stirring rate in step (2) is 200~700 r / min, the stirring time is 5~10 min, and the stirring temperature is room temperature; And / or, the curing temperature is 60~80℃, and the curing time is 10~15h.

6. The application of the photochromic film with multiple photoresponses as described in any one of claims 1 to 3 or the photochromic film with multiple photoresponses prepared by the preparation method described in any one of claims 4 to 5 in information storage, optical encryption and anti-counterfeiting.

7. The application according to claim 6, characterized in that, Under red and green light irradiation, the photosensitive monomer in the photochromic film with multiple photoresponses undergoes a reversible Z / E configuration transition in the neutral state, accompanied by a corresponding color change. Under ultraviolet light irradiation, the photoacid monomer in the photochromic film with multiple photoresponses is excited to release proton hydrogen. This proton hydrogen specifically binds to the nitrogen atom of the dimethylamino group in the photosensitive monomer, thereby causing the photosensitive monomer to undergo a configuration transition from the neutral state to the proton state, resulting in a significant color change in the photochromic film with multiple photoresponses.

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