A time-locked fiber self-erasing material with step-by-step decryption function for special information transmission, its preparation method, and its anti-counterfeiting application.

Abstract

This invention discloses a time-locked fiber self-erasing material with a step-by-step decryption function for special information transmission, its preparation method, and its anti-counterfeiting applications. The material is prepared by chemically grafting amino-modified phosphors onto the surface of carboxylated cellulose nanocrystals, followed by electrostatic attraction between the phosphors and gold nanoclusters stabilized by the carboxylated cellulose nanocrystals. The material of this invention uses carboxylated cellulose nanocrystals as a bridge connecting the donor and acceptor, inhibiting the self-aggregation of gold nanoclusters, enhancing fluorescence intensity and stability, and improving the energy transfer efficiency between the donor and acceptor. Based on changes in the degree of energy transfer, the time-locked fiber self-erasing material exhibits a color pattern over a time scale, adjusted by the donor-acceptor ratio.

Description

Technical Field

[0001] This invention belongs to the field of biomass fiber modification technology, specifically relating to a time-locked fiber self-erasing material with a step-by-step decryption function for special information transmission, its preparation method, and its anti-counterfeiting application. Background Technology

[0002] Anti-counterfeiting applications are playing an increasingly important role in reducing future counterfeiting problems. Traditional barcodes or watermarks have been well-received for anti-counterfeiting, but they are easily copied by counterfeiters and cannot meet market demands. Therefore, it is necessary to develop advanced information encryption and anti-counterfeiting strategies that are difficult to replicate. To address these issues, stimulus-response information encryption technology has been proposed to achieve higher anti-counterfeiting strength. When faced with a stimulus, important information is presented in an "on-off" manner. Self-erasing materials have attracted much attention due to their time-dependent properties, and the stored valid information can only be obtained within a certain period of time; otherwise, it is erroneous. Information decryption is usually achieved through ultraviolet light stimulation, but real-time fluorescence is easily interfered with by background or contaminants, leading to information confusion and indistinguishability. Phosphorescent materials have been widely used in information encryption because they can overcome light interference problems and have excellent delayed emission properties. Phosphorescent materials can be divided into organic and inorganic molecules, but organic ultralong phosphorescent materials are rarely realized, which limits the practicality of time-dependent inertial recognition. Compared to organic molecules, inorganic molecules form ordered structures through crystallization, polymerization, and doping of organic host-guest matrices, providing a stringent environment for extending the lifetime of phosphors and attracting widespread attention. Persistent luminescent phosphors possess background-free properties and utilize extended duration for information encryption, finding wide application in time-dependent anti-counterfeiting. Firstly, the time-dependent characteristics of phosphors can be controlled through incident (irradiation time, energy absorption) and emission (free energy dissipation, absorption / transfer emission) methods. Phosphors reach their energy saturation point quickly, making precise control of irradiation time and energy for ideal results challenging. Furthermore, the influence of ambient natural light also limits incident mode control. Secondly, the avoidance of emission energy free energy dissipation is problematic because phosphors emit light for hours or even longer after excitation ceases, hindering operation. Therefore, a new method for controlling emission is needed to achieve time-dependent targets by transferring emission energy. In fluorescence resonance energy transfer (FRET) systems, the degree of spectral overlap and the distance between donor and acceptor affect energy transfer efficiency, limiting its application in response and anti-counterfeiting. Furthermore, phosphor donors are prone to decomposition and have poor dispersibility, lacking binding sites with inorganic acceptors in water. This limitation makes direct binding to the acceptor an unattainable goal for FRET. Therefore, it is necessary to find a suitable assembly strategy to uniformly distribute the acceptor on the phosphor donor surface, thereby developing a multifunctional FRET platform with both responsive and time-varying information encryption. Summary of the Invention

[0003] The purpose of this invention is to provide a time-locked fiber self-erasing material with a step-by-step decryption function for special information transmission, its preparation method, and its application in information anti-counterfeiting. The material can exhibit a series of information in response to cysteine ​​and pH under 365nm ultraviolet light and present the correct information at a specific time after the ultraviolet light is turned off.

[0004] The above-mentioned objectives of the present invention are achieved through the following technical solutions:

[0005] A method for preparing a time-locked fiber self-erasing material with step-by-step decryption function for special information transmission includes the following steps:

[0006] S1. Preparation of carboxylated cellulose nanocrystal-based phosphor material: Carboxylated cellulose nanocrystals are subjected to an amidation reaction with amino-modified phosphor under the action of a catalyst to obtain carboxylated cellulose nanocrystal-based phosphor material.

[0007] S2. Preparation of carboxylated cellulose nanocrystal-stabilized gold nanocluster materials: Glutathione solution and carboxylated cellulose nanocrystal suspension were mixed and stirred. HAuCl4 solution was added to the mixture. After the reaction system turned colorless, the pH was adjusted to alkaline. NaBH4 solution was added. After the reaction system turned orange-red, the pH was adjusted to acidic. Stirring was continued until the reaction was completed to obtain carboxylated cellulose nanocrystal-stabilized gold nanocluster materials.

[0008] S3. Preparation of time-locked fiber self-erasing material with step-by-step decryption function for special information transmission: The prepared carboxylated cellulose nanocrystal-based phosphor material and carboxylated cellulose nanocrystal-stabilized gold nanocluster material are mixed and stirred to prepare a time-locked fiber self-erasing material with step-by-step decryption function for special information transmission.

[0009] Further, the specific operation for preparing the carboxylated cellulose nanocrystal phosphor material in step S1 is as follows: the carboxylated cellulose nanocrystal suspension is stirred to disperse it evenly, and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide are added in sequence, stirred for 30-60 min, amino-modified phosphor is added to the solution, and the reaction is carried out with continuous shaking at 24-28℃ for 4-8 h to complete the amidation reaction; the mass ratio of the carboxylated cellulose nanocrystals to the amino-modified phosphor is 1-10:1;

[0010] Further, the specific operation for preparing the carboxylated cellulose nanocrystal-stabilized gold nanocluster material in step S2 is as follows: Glutathione solution and carboxylated cellulose nanocrystal suspension are mixed and stirred. Then, HAuCl4 solution is added to the mixture. After the reaction system changes from yellow to colorless, ultrapure water is added, and the pH is adjusted to 11-12 with NaOH solution. NaBH4 solution is added, and the reaction is carried out for 20-40 minutes. After the reaction system changes from colorless to orange-red, the pH is adjusted to 2-3 with HCl solution. The reaction is then carried out at 24-28℃ and 400-600 rpm. Stirring for 4–8 hours yielded a gold nanocluster material stabilized by carboxylated cellulose nanocrystals. The addition ratio of glutathione solution, carboxylated cellulose nanocrystal suspension, HAuCl4 solution, and NaBH4 solution was 3.2–12.8 mL: 0.03–0.05 mL: 1.6–6.4 mL: 1.6–6.4 mL. The corresponding concentrations were: glutathione solution concentration of 10 mM, solid content of carboxylated cellulose nanocrystal suspension of 2.322%, HAuCl4 solution concentration of 10 mM, and NaBH4 solution concentration of 2 mM.

[0011] Furthermore, in step S3, the volume ratio of carboxylated cellulose nanocrystal-based phosphor material to carboxylated cellulose nanocrystal-stabilized gold nanoclusters is 3:2 to 12.

[0012] The time-locked fiber self-erasing material of this invention, featuring a step-by-step decryption function for special information transmission, is prepared by electrostatic attraction between a phosphor chemically grafted with amino groups onto the surface of carboxylated cellulose nanocrystals and a gold nanocrystal-stabilized material. Excited with 365 nm UV light, the time-locked fiber self-erasing material exhibits emission peaks at 520 nm and 666 nm, corresponding to the emission peaks of the phosphor and the gold nanocrystals, respectively. A FRET exists between the carboxylated cellulose nanocrystal-based phosphor (donor) and the carboxylated cellulose nanocrystal-stabilized gold nanocrystals (acceptor) in the time-locked fiber self-erasing material. As the proportion of the cellulose nanocrystal-stabilized gold nanocrystals increases, the color of the solution changes from cyan to red. After the UV lamp is turned off, the green color of the solution gradually weakens. With increasing cysteine ​​solution concentration and pH (pH = 2–9), the emission intensity of the time-locked fiber self-erasing material at 666 nm gradually quenches, while the emission intensity at 520 nm gradually increases. Finally, when the cysteine ​​solution concentration reaches 20 μM or pH = 9, the emission of the carboxylated cellulose nanocrystal-stabilized gold nanoclusters is essentially zero. Therefore, in the application of the time-locked fiber self-erasing material prepared in this invention for information anti-counterfeiting, the information display time can be controlled by adjusting the ratio of carboxylated cellulose nanocrystal-based phosphor material (donor) to carboxylated cellulose nanocrystal-stabilized gold nanoclusters material (acceptor) in the time-locked fiber self-erasing material.

[0013] The specific application involves adding carboxylated cellulose nanocrystalline phosphor material and time-locked fiber self-erasing material with step-by-step decryption function for special information transmission to a model tank for encryption. Then, a 20 μM cysteine ​​solution and a pH=9 solution are added to the designated positions. Under ultraviolet light irradiation, a series of decrypted information is formed. Finally, after the ultraviolet light is turned off, there is a FRET between the donor and acceptor of the time-locked fiber self-erasing material. The information displayed at the designated time is the correct information to be expressed.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) The method of this invention uses carboxylated cellulose nanocrystals as a bridge connecting the donor (carboxylated cellulose nanocrystal-based phosphor material) and the acceptor (carboxylated cellulose nanocrystal-stabilized gold nanoclusters), promoting the FRET process between the donor and acceptor, improving energy transfer efficiency, inhibiting the self-aggregation of gold nanoclusters, and enhancing fluorescence intensity and stability. Based on the change in the degree of energy transfer, the time-locked fiber self-erasing material is adjusted by the ratio of donor and acceptor, thereby exhibiting a color pattern on the time scale.

[0016] (2) The time-locked fiber self-erasing material of this invention exhibits excellent pH and cysteine ​​responses under ultraviolet light excitation. Due to the FRET process, the fluorescence color of the time-locked fiber self-erasing material can transition from orange-red to green under pH and cysteine ​​stimulation. By adjusting the ratio of donor to acceptor, the energy transfer degree and formation mode of the time-locked fiber self-erasing material are changed, thus achieving time-locking of information and displaying a series of information over time. In short, the information is "locked" in time and can only be decrypted using a suitable "time key". This invention utilizes the unique continuous luminescence properties of the phosphor donor and the responsiveness of the gold nanocluster acceptor to construct an FRET system, which can provide inspiration for time-dependent multifunctional responses and the security of information transmission. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the slot in the "8 8 8" model.

[0018] In the diagram, from left to right, there are the first "8", the second "8" and the third "8"; each "8" is divided into 7 slots, labeled "1, 2, 3, 4, 5, 6 and 7" respectively, just like the slot labeling of the third "8". Detailed Implementation

[0019] Example 1

[0020] S1. Preparation of carboxylated cellulose nanocrystal-based phosphor material: A suspension of carboxylated cellulose nanocrystals with a solid content of 2.322% (mass of carboxylated cellulose nanocrystals is 0.1 g) was stirred to disperse it evenly. Then, 0.1 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 0.1 g of N-hydroxysuccinimide were added in sequence and stirred for 45 min. 0.1 g of amino-modified phosphor was added to the solution and the reaction was carried out by continuous shaking at 26 °C for 6 h to complete the amidation reaction. The resulting product is the carboxylated cellulose nanocrystal-based phosphor material.

[0021] S2. Preparation of carboxylated cellulose nanocrystal-stabilized gold nanoclusters: 3.2 mL of a 10 mM glutathione solution and 0.03 mL of a 2.322% solids content carboxylated cellulose nanocrystal suspension were mixed and stirred for 5 min. Then, 1.6 mL of a 10 mM HAuCl4 solution was added to the mixture, and the reaction system changed from yellow to colorless. Next, 5.0 mL of ultrapure water was added, and the mixture was stirred vigorously for 5 min. The pH of the mixture was adjusted to 11 with a 1 M NaOH solution. Then, 1.6 mL of a 2 mM NaBH4 solution was slowly added, and the reaction was carried out for 30 min. The color of the reaction system changed from colorless to orange-red. The pH of the mixture was adjusted to 2 with a 1 M HCl solution to quench excess NaBH4. Finally, the reaction solution was stirred at 26 °C and 500 rpm for 6 h. The resulting product was the carboxylated cellulose nanocrystal-stabilized gold nanoclusters.

[0022] S3. Preparation of time-locked fiber self-erasing material with step-by-step decryption function for special information transmission: 1 mL of carboxylated cellulose nanocrystal-based phosphor material obtained in step S1 and 4 mL of carboxylated cellulose nanocrystal-stabilized gold nanoclusters material obtained in step S2 were added to 1.0 mL of ultrapure water and mixed and stirred for 8 h to disperse it evenly and store it at 4 °C.

[0023] An application example of the time-locked fiber self-erasing material with step-by-step decryption function for information transmission prepared in Example 1 in information anti-counterfeiting: The carboxylated cellulose nanocrystalline phosphor material prepared in step S1 was added to the first "8" in the digital "88 8" model slot. The time-locked fiber self-erasing material with step-by-step decryption function for information transmission prepared in step S3 was added to the second and third "8"s in the digital "88 8" model slot for encryption. Subsequently, a 20 μM cysteine ​​solution was added to slots "1, 2, 3, 4, 5" in the third "8", and a NaOH solution with pH=9 was added to slots "2, 3" in the second "8". Figure 1 As shown, a series of decrypted messages were formed under 365nm ultraviolet light irradiation: "8 8 8, 8E1 13, 8E1 8, 8 8 13, 8E 8, 8 8 3". Finally, after the ultraviolet light was turned off, a FRET (Frequency-Related Evidence-Eliminating Transmission) was observed between the donor and acceptor of the time-locked fiber self-erasing material. The green number "8 1 3" was observed after 2 minutes, representing the correct message.

[0024] Example 2

[0025] S1. Preparation of carboxylated cellulose nanocrystal-based phosphor material: A suspension of carboxylated cellulose nanocrystals with a solid content of 2.322% (mass of carboxylated cellulose nanocrystals is 0.1g) was stirred to disperse it evenly. Then, 0.02g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 0.02g of N-hydroxysuccinimide were added in sequence and stirred for 30min. 0.02g of amino-modified phosphor was added to the solution and the reaction was carried out by continuous shaking at 24℃ for 4h to complete the amidation reaction. The resulting product is the carboxylated cellulose nanocrystal-based phosphor material.

[0026] S2. Preparation of carboxylated cellulose nanocrystal-stabilized gold nanoclusters: 6.4 mL of a 10 mM glutathione solution and 0.04 mL of a 2.322% solids content carboxylated cellulose nanocrystal suspension were mixed and stirred for 5 min. Then, 3.2 mL of a 10 mM HAuCl4 solution was added to the mixture, and the reaction system changed from yellow to colorless. Next, 5.0 mL of ultrapure water was added, and the mixture was stirred vigorously for 5 min. The pH of the mixture was adjusted to 11.5 with a 1 M NaOH solution. Then, 3.2 mL of a 2 mM NaBH4 solution was slowly added, and the reaction was carried out for 20 min. The color of the reaction system changed from colorless to orange-red. The pH of the mixture was adjusted to 2.5 with a 1 M HCl solution to quench excess NaBH4. Finally, the reaction solution was stirred at 24 °C and 400 rpm for 4 h. The resulting product was the carboxylated cellulose nanocrystal-stabilized gold nanoclusters.

[0027] S3. Preparation of time-locked fiber self-erasing material with step-by-step decryption function for special information transmission: 2 mL of carboxylated cellulose nanocrystal-based phosphor material obtained in step S1 and 3 mL of carboxylated cellulose nanocrystal-stabilized gold nanocluster material obtained in step S2 were added to 1.0 mL of ultrapure water and mixed and stirred for 6 h to disperse it evenly and store it at 4 °C.

[0028] An application example of the time-locked fiber self-erasing material with step-by-step decryption function for information transmission prepared in Example 2 in information anti-counterfeiting: The carboxylated cellulose nanocrystalline phosphor material prepared in step S1 was added to the first "8" in the digital "88 8" model slot. The time-locked fiber self-erasing material with step-by-step decryption function for information transmission prepared in step S3 was added to the second and third "8"s in the digital "88 8" model slot for encryption. Subsequently, a 20 μM cysteine ​​solution was added to slots "1, 2, 3, 4, 5" in the third "8", and a NaOH solution with pH=9 was added to slots "2, 3" in the second "8". Figure 1As shown, a series of decrypted messages were generated under 365nm ultraviolet light irradiation: "8 8 8, 8E1 13, 8E1 8, 8 8 13, 8E 8, 8 8 3". Finally, after the ultraviolet light was turned off, a FRET (Frequency-Related Evidence-Eliminating Transmission) was observed between the donor and acceptor of the time-locked fiber self-erasing material. The green number "8 1 3" was observed after 1 minute, representing the correct message.

[0029] Example 3

[0030] S1. Preparation of carboxylated cellulose nanocrystal-based phosphor material: A suspension of carboxylated cellulose nanocrystals with a solid content of 2.322% (mass of carboxylated cellulose nanocrystals is 0.1g) was stirred to disperse it evenly. Then, 0.01g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 0.01g of N-hydroxysuccinimide were added in sequence and stirred for 60min. 0.01g of amino-modified phosphor was added to the solution and the reaction was carried out by continuous shaking at 28℃ for 8h to complete the amidation reaction. The resulting product is the carboxylated cellulose nanocrystal-based phosphor material.

[0031] S2. Preparation of carboxylated cellulose nanocrystal-stabilized gold nanoclusters: 12.8 mL of a 10 mM glutathione solution and 0.05 mL of a 2.322% solids content carboxylated cellulose nanocrystal suspension were mixed and stirred for 5 min. Then, 6.4 mL of a 10 mM HAuCl4 solution was added to the mixture, and the color of the reaction system changed from yellow to colorless. Next, 5.0 mL of ultrapure water was added, and the mixture was stirred vigorously for 5 min. The pH of the mixture was adjusted to 12 with a 1 M NaOH solution. Then, 6.4 mL of a 2 mM NaBH4 solution was slowly added, and the reaction was carried out for 40 min. The color of the reaction system changed from colorless to orange-red. The pH of the mixture was adjusted to 3 with a 1 M HCl solution to quench excess NaBH4. Finally, the reaction solution was stirred at 28 °C and 600 rpm for 8 h. The resulting product was the carboxylated cellulose nanocrystal-stabilized gold nanoclusters.

[0032] S3. Preparation of time-locked fiber self-erasing material with step-by-step decryption function for special information transmission: 3 mL of carboxylated cellulose nanocrystal-based phosphor material obtained in step S1 and 2 mL of carboxylated cellulose nanocrystal-stabilized gold nanocluster material obtained in step S2 were added to 1.0 mL of ultrapure water and mixed and stirred for 10 h to disperse it evenly and store it at 4℃.

[0033] An application example of the time-locked fiber self-erasing material with step-by-step decryption function for information transmission prepared in Example 3 in information anti-counterfeiting: The carboxylated cellulose nanocrystalline phosphor material prepared in step S1 was added to the first "8" in the digital "88 8" model slot. The time-locked fiber self-erasing material with step-by-step decryption function for information transmission prepared in step S3 was added to the second and third "8"s in the digital "88 8" model slot for encryption. Subsequently, a 20 μM cysteine ​​solution was added to slots "1, 2, 3, 4, 5" in the third "8", and a NaOH solution with pH=9 was added to slots "2, 3" in the second "8". Figure 1 As shown, a series of decrypted messages were generated under 365nm ultraviolet light irradiation: "8 8 8, 8E1 13, 8E1 8, 8 8 13, 8E 8, 8 8 3". Finally, after the ultraviolet light was turned off, a FRET (Frequency-Related Evidence-Elimination) was observed between the donor and acceptor of the time-locked fiber self-erasing material. At 30s, the green number "8 1 3" was observed, which represents the correct message.

[0034] As demonstrated in Examples 1-3, this invention can control the information display time by adjusting the ratio of carboxylated cellulose nanocrystal-based phosphor material (donor) to carboxylated cellulose nanocrystal-stabilized gold nanoclusters material (acceptor) in the time-locked fiber self-erasing material with step-by-step decryption function for special information transmission. For example, in Example 1, the volume ratio of carboxylated cellulose nanocrystal-based phosphor material to carboxylated cellulose nanocrystal-stabilized gold nanoclusters material in the time-locked fiber self-erasing material with step-by-step decryption function for special information transmission is 1:4. In the application example, a series of decrypted messages are formed under ultraviolet light irradiation. Finally, after the ultraviolet light is turned off, the information displayed at the specified time "2 minutes" is the correct message. In Example 2, the volume ratio of carboxylated cellulose nanocrystal-based phosphor to carboxylated cellulose nanocrystal-stabilized gold nanoclusters in the time-locked fiber self-erasing material with step-by-step decryption function for special information transmission is 2:3. In the application example, a series of decrypted messages are formed under ultraviolet light irradiation. Finally, after the ultraviolet light is turned off, the message "8 1 3 green numbers" displayed at a specified time "1 min" represents the correct information. In Example 3, the volume ratio of carboxylated cellulose nanocrystal-based phosphor to carboxylated cellulose nanocrystal-stabilized gold nanoclusters in the time-locked fiber self-erasing material with step-by-step decryption function for special information transmission is 3:2. In the application example, a series of decrypted messages are formed under ultraviolet light irradiation. Finally, after the ultraviolet light is turned off, the message "8 1 3 green numbers" displayed at a specified time "30 s" represents the correct information.

Claims

1. A method for preparing a time-locked fiber self-erasing material with a step-by-step decryption function for special information transmission, characterized in that, Includes the following steps: S1. Preparation of carboxylated cellulose nanocrystal-based phosphor material: Carboxylated cellulose nanocrystals are subjected to an amidation reaction with amino-modified phosphor under the action of a catalyst to obtain carboxylated cellulose nanocrystal-based phosphor material. S2. Preparation of carboxylated cellulose nanocrystal-stabilized gold nanocluster materials: Glutathione solution and carboxylated cellulose nanocrystal suspension were mixed and stirred. HAuCl4 solution was added to the mixture. After the reaction system turned colorless, the pH was adjusted to alkaline. NaBH4 solution was added. After the reaction system turned orange-red, the pH was adjusted to acidic. Stirring was continued until the reaction was completed to obtain carboxylated cellulose nanocrystal-stabilized gold nanocluster materials. S3. Preparation of time-locked fiber self-erasing material with step-by-step decryption function for special information transmission: The prepared carboxylated cellulose nanocrystal-based phosphor material and carboxylated cellulose nanocrystal-stabilized gold nanocluster material are mixed and stirred to prepare a time-locked fiber self-erasing material with step-by-step decryption function for special information transmission. The mass ratio of the carboxylated cellulose nanocrystals to the amino-modified phosphor is 1~10:1; In step S3, the volume ratio of carboxylated cellulose nanocrystal-based phosphor material to carboxylated cellulose nanocrystal-stabilized gold nanoclusters is 3:2~12.

2. The preparation method according to claim 1, characterized in that, The specific operation for preparing the carboxylated cellulose nanocrystal-based phosphor material in step S1 is as follows: the carboxylated cellulose nanocrystal suspension is stirred to disperse it evenly, and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide are added in sequence. The mixture is stirred for 30-60 min, and then amino-modified phosphor is added to the solution. The mixture is continuously shaken at 24-28℃ for 4-8 h to complete the amidation reaction.

3. The preparation method according to claim 1, characterized in that, The specific operation for preparing the carboxylated cellulose nanocrystal-stabilized gold nanocluster material in step S2 is as follows: Glutathione solution and carboxylated cellulose nanocrystal suspension are mixed and stirred. Then, HAuCl4 solution is added to the mixture. After the reaction system changes from yellow to colorless, ultrapure water is added, and the pH is adjusted to 11-12 with NaOH solution. NaBH4 solution is added, and the reaction proceeds for 20-40 min. After the reaction system changes from colorless to orange-red, the pH is adjusted to 2-3 with HCl solution. The mixture is stirred at 24-28°C and 400-600 rpm for 4-8 h to obtain the carboxylated cellulose nanocrystal-stabilized gold nanocluster material. The ratio of glutathione solution, carboxylated cellulose nanocrystal suspension, HAuCl4 solution, and NaBH4 solution added is 3.2-12.8 mL: 0.03-0.05 mL: 1.6-6.4 mL: 1.6-6.4 mL; the corresponding concentration of the glutathione solution is 10... The solid content of the carboxylated cellulose nanocrystal suspension was 2.322%, the concentration of the HAuCl4 solution was 10 mM, and the concentration of the NaBH4 solution was 2 mM.

4. The time-locked fiber self-erasing material with step-by-step decryption function for special information transmission prepared by the preparation method of claim 1.

5. The application of the time-locked fiber self-erasing material with step-by-step decryption function for special information transmission prepared by the preparation method of claim 1 in information anti-counterfeiting.

6. The application according to claim 5, characterized in that, The information display time is controlled by adjusting the ratio of carboxylated cellulose nanocrystal-based phosphor material to carboxylated cellulose nanocrystal-stabilized gold nanoclusters in a time-locked fiber self-erasing material with a step-by-step decryption function for special information transmission.

7. The application according to claim 5, characterized in that, Carboxylated cellulose nanocrystalline phosphor material and time-locked self-erasing fiber material with step-by-step decryption function for special information transmission are added to the model tank for encryption. Then, a 20 μM cysteine ​​solution and a solution with pH=9 are added to the designated position. Under ultraviolet light irradiation, a series of decrypted information is formed. Finally, after the ultraviolet light is turned off, the information displayed at the designated time is the correct information to be expressed.

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