Fluorescent waterborne polyurethane with anti-counterfeiting function and preparation and application thereof

Abstract

The present application belongs to the field of fluorescent anti-counterfeiting waterborne polyurethane, and discloses a fluorescent waterborne polyurethane with anti-counterfeiting function and preparation and application thereof. The fluorescent waterborne polyurethane with anti-counterfeiting function is obtained by taking polycarbonate diol and diisocyanate as raw materials, and introducing europium ions, potassium ions, naphthalimide derivatives and anthracene derivatives as two kinds of chain extenders. The fluorescent waterborne polyurethane obtained by the present application has good mechanical properties, the tensile strength can reach 74.75+ / -3.4 MPa, the pencil hardness can reach 2H, has strong adhesion, good flexibility, and maintains the self-repairing efficiency of 83.2%; and has stable fluorescent properties, unique responsiveness to high-intensity ultraviolet light, can realize information encryption, and has certain application prospect in anti-counterfeiting labels, identification platforms and intelligent display.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of fluorescent anti-counterfeiting waterborne polyurethane, and particularly relates to a fluorescent waterborne polyurethane with anti-counterfeiting function and preparation and application thereof. BACKGROUND

[0002] Waterborne polyurethane coating has great development potential due to its advantages such as good adhesion, good flexibility, clean and no pollution. However, the functionalization of waterborne polyurethane is difficult due to the unique water-based environment, which limits the application of waterborne polyurethane coating in more fields. Therefore, the functionalization of waterborne coating has important significance for broadening its application field and promoting the development of waterborne polyurethane coating. Fluorescent ink has the advantages of bright color and simple preparation process, and has a wide application in anti-counterfeiting printing, display devices, biological imaging and other fields. Compared with inorganic luminescent ink, waterborne fluorescent ink has the advantages of high luminescent efficiency, low carbon, non-toxicity and easy recycling. However, the waterborne luminescent ink on the market is mostly prepared by physical blending, which has the disadvantages of reduced fluorescence intensity and poor stability. Therefore, the development of multifunctional waterborne polyurethane ink with intrinsic fluorescence is a practical research direction.

[0003] Chinese patent publication CN107746667A discloses a preparation method of polyurethane luminescent coating, which mixes polyurethane, fluorescent powder, curing agent, defoaming agent and thickening agent to obtain polyurethane luminescent coating. However, the color and fluorescence performance of the coating obtained by this method will deteriorate with the increase of use time, and this method is not environmentally friendly and will pollute the environment. Chinese patent publication CN110330622A discloses a fluorescent waterborne polyurethane and a preparation method thereof, which introduces fluorescent groups into the system in the form of a chain extender, and the fluorescence performance can be maintained to a certain extent. Chinese patent publication CN116004102A discloses a waterborne polyurethane coating with fluorescent properties and a preparation method thereof, which has the advantages of pollution-free, non-toxic, easy to popularize and apply. SUMMARY

[0004] In order to overcome the shortcomings and deficiencies of the prior art, the primary purpose of the present application is to provide a preparation method of fluorescent waterborne polyurethane with anti-counterfeiting function.

[0005] Another purpose of the present application is to provide a fluorescent waterborne polyurethane with anti-counterfeiting function prepared by the above method.

[0006] Still another purpose of the present application is to provide the application of the above fluorescent waterborne polyurethane with anti-counterfeiting function in anti-counterfeiting labels, identification platforms or intelligent displays.

[0007] The purposes of the present application are achieved by the following schemes:

[0008] A preparation method of fluorescent waterborne polyurethane with anti-counterfeiting function, comprising the following steps:

[0009] 1) mixing and stirring polycarbonate diol with diisocyanate, adding catalyst, and continuing to stir to obtain a prepolymer;

[0010] 2) adding fluorescent chain extender and 1,4-butanediol to the prepolymer and stirring to obtain an intermediate product containing fluorescent groups;

[0011] 3) adding a hydrophilic chain extender to the intermediate product containing fluorescent groups and stirring to obtain an intermediate product containing hydrophilic groups;

[0012] 4) adding a benzidine to the intermediate product containing hydrophilic groups and stirring;

[0013] 5) adding triethylamine to the solution obtained in step 4) for neutralization;

[0014] 6) adding an inorganic europium salt, an organic potassium salt and water to the solution obtained in step 5) and stirring to obtain an emulsion, and solidifying to obtain fluorescent waterborne polyurethane with anti-counterfeiting function.

[0015] The polycarbonate diol in step 1) is at least one of PCDL1000 and PCDL2000.

[0016] The diisocyanate in step 1) is at least one of hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4'-diphenyl methane diisocyanate (MDI), 4,4'-dicyclohexyl methane diisocyanate (HMDI), and toluene diisocyanate (TDI).

[0017] The molar ratio of the diisocyanate to the polycarbonate diol in step 1) is 2-3:1.

[0018] The catalyst in step 1) is at least one of stannous octoate, stannous oleate, and dibutyltin dilaurate; and the use amount ratio of the catalyst to the polycarbonate diol is 1 drop: 4-6 mmol.

[0019] The polycarbonate diol in step 1) is subjected to water removal treatment before mixing and stirring, specifically, the polycarbonate diol is placed in a vacuum, and water is removed at 110-120°C for 1-3h to remove water and other small molecular substances in the polycarbonate diol, and the polycarbonate diol is prepared for use.

[0020] The temperature of the mixing and stirring in step 1) is 80-90°C, the time of the mixing and stirring is 0.5-1.5h, and the time of the continuous stirring is 2.5-4h.

[0021] The mixing and stirring in step 1) is carried out under N2 or Ar atmosphere.

[0022] The fluorescent chain extender in step 2) is a naphthalimide derivative BAT and an anthracene derivative ADO, and the structural formula is as follows:

[0023]

[0024] The naphthalimide derivative is prepared by the following steps:

[0025] Naphthalic anhydride and aminodiol are reacted at 80°C for 12-24h, and the solvent is removed, washed and dried to obtain an intermediate; the intermediate and aminoindole are reacted in dimethyl sulfoxide at 80°C for 12-24h, centrifuged, impurities are removed, and dried to obtain a naphthalimide derivative (BAT);

[0026] The anthracene derivative is prepared by the following steps:

[0027] Potassium carbonate, anthracene bromide and alcohol amine are mixed and stirred in dimethyl sulfoxide, and reacted at 80°C for 4-5h, and then filtered, impurities are removed, and dried to obtain a light yellow anthracene derivative (ADO).

[0028] The molar ratio of the fluorescent chain extender, 1,4-butanediol and the polycarbonate diol in step 1) in step 2) is 0.25-4.25:0.25-4.25:50.

[0029] The molar ratio of the naphthalimide derivative and the anthracene derivative in the fluorescent chain extender in step 2) is 0.25:0.5-4.

[0030] The stirring time in step 2) is 2-3h.

[0031] The hydrophilic chain extender in step 3) is at least one of 2,2-dimethylol propionic acid, 2,2-dimethylol butyric acid, and ethylenediamine sodium ethanesulfonate.

[0032] The molar ratio of the hydrophilic chain extender and the diisocyanate in step 1) in step 3) is 1:10-2:5.

[0033] The stirring temperature in step 3) is 70-80°C, and the stirring time is 1.5-2.5h.

[0034] The benzidine in step 4) is at least one of o-dianisidine, m-dianisidine and 3,3'-dimethoxybenzidine.

[0035] The molar ratio of the benzidine and the diisocyanate in step 1) in step 4) is 1:10-2:5.

[0036] The stirring temperature in step 4) is 40-50°C, and the stirring time is 2.5-3.5h.

[0037] The molar ratio of the triethylamine to the hydrophilic chain extender in step 3) is 1:1.

[0038] The temperature of the neutralization in step 5) is room temperature; and the stirring time of the neutralization is 0.5-1h.

[0039] The inorganic europium salt in step 6) is at least one of europium nitrate, europium carbonate, europium acetate and europium sulfate.

[0040] The organic potassium salt in step 6) includes at least one of potassium acetate, potassium propionate, potassium lactate and potassium citrate.

[0041] The molar ratio of the inorganic europium salt and the organic potassium salt to the benzidine in step 4) is 0.25:1.25-10:20.

[0042] The amount of water in step 6) is sufficient to make the solid content of the emulsion 35wt%-40wt%.

[0043] The temperature of the stirring in step 6) is 25-35℃; the stirring speed is 1000r / min-1500r / min; and the stirring time is 0.5-1h.

[0044] The solidification in step 6) is specifically forming by solidifying the emulsion on a substrate or curing by air drying the emulsion in a mold.

[0045] The substrate is one of 50# steel plate, epoxy plate, bakelite plate, PC plate, glass plate and acrylic plate.

[0046] The conditions for forming by solidifying the emulsion on a substrate are baking at 100-130℃ in a blast oven for 0.1-0.5h; and the conditions for curing by air drying are air drying at room temperature for 24h-72h, and then baking at 80-100℃ in a blast oven for 6-12h.

[0047] The fluorescent waterborne polyurethane with anti-counterfeiting function prepared by the above method.

[0048] The fluorescent waterborne polyurethane with anti-counterfeiting function is applied to anti-counterfeiting labels, identification platforms or intelligent displays.

[0049] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0050] 1.The present invention introduces naphthalimide-based chain extender (BAT) and anthracene-based chain extender (ADO) into waterborne polyurethane (WPU) to prepare a fluorescent waterborne polyurethane (FWPU) with stable emulsion performance, which can be printed on various substrates by simple adjustment. The obtained fluorescent waterborne polyurethane has good mechanical properties and excellent self-repairing efficiency, and excellent flexibility and excellent adhesion (ISO level 0) on various substrates. Due to the introduction of cations to construct a non-covalent physical cross-linking network based on double cation-π interaction, the tensile properties of the FWPU reach 74.75±3.4MPa, the hardness reaches 2H, while maintaining 83.2% self-repairing efficiency.

[0051] 2.The present invention introduces naphthalimide derivatives, anthracene derivatives and europium ions, so that the obtained fluorescent waterborne polyurethane has excellent photoluminescence performance, and can input encrypted information into the polyurethane using high-intensity 254nm ultraviolet light, and can realize double information encryption with 365nm information input, which has certain application prospect in anti-counterfeiting labels, identification platforms and intelligent displays.

[0052] 3.Fluorescent properties and anti-counterfeiting applications of FWPU: FWPU can realize various colors, and its fluorescence has excellent stability (water resistance, acid and alkali resistance, heat resistance and light resistance), and has unique responsiveness to high-intensity ultraviolet light. Using this characteristic, information and patterns can be input on the FWPU, the information can be encrypted, and information matrices can be formed by information units to express information. In addition, the FWPU emulsion only needs to add a small amount of defoaming agent and thickening agent to be used as a waterborne fluorescent ink with excellent performance, which can be printed on various substrates combined with screen printing technology.

[0053] 4.The synthesis conditions of the present invention are mild, the preparation process is simple, and the raw materials are easy to obtain. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 is the stress-strain curve of each example and comparative example.

[0055] Figure 2 is the fluorescence performance display diagram of Example 1 after being placed at pH=7, pH=13, pH=1, 100℃ for 240h.

[0056] Figure 3 is the comparison diagram of Example 1 under 254nm irradiation after being placed in the open air for 15 days.

[0057] Figure 4 is the information input schematic diagram of Example 1 polyurethane and the different information expression diagram of Example 1 polyurethane under different wavelength ultraviolet light excitation.

[0058] Figure 5 is a schematic diagram of the responsive preparation of information elements using the polyurethane of Example 1 to long-time irradiation of 254 nm ultraviolet light and a matrix of information element composition showing different information expression at 365 nm and 254 nm.

[0059] Figure 6 is a picture of information expression of the polyurethane of Example 1 at visible light, 254 nm and 365 nm and a display picture of various pattern information input on the polyurethane of Example 1 using 254 nm ultraviolet light.

[0060] Figure 7 is the nuclear magnetic resonance carbon spectrum of the BAT and ADO of the present application.

[0061] Figure 8 is the nuclear magnetic resonance hydrogen spectrum of the BAT and ADO of the present application. DETAILED DESCRIPTION

[0062] The present application will be further described in detail by the following examples and drawings, but the embodiments of the present application are not limited thereto. In the examples, the specific conditions not mentioned are carried out according to the conventional conditions or the conditions suggested by the manufacturers. The reagents or instruments used are not mentioned the manufacturers, which are all the conventional products available in the market.

[0063] The reagents used in the examples are all the conventional products available in the market, unless otherwise specified.

[0064] In the following preparation, the parts mentioned are all the molar parts, wherein "1 part" is "1 mmol".

[0065] Preparation of naphthalimide derivative (BAT):

[0066]

[0067] 1) Weigh 30 parts of 4-bromo-1,8-naphthalic anhydride in a single-necked flask, then add 90 parts of 2-amino-1,3-propanediol and 120 mL of ethanol. After heating at 80°C under reflux for 12 h, a rotary evaporator is used to remove the excess ethanol. Finally, wash with deionized water for 3 times, and dry at 50°C under vacuum for 12 h to obtain a light yellow powder intermediate.

[0068] 2) Weigh 5 parts of the light yellow powder intermediate in a single-necked flask, add 5.1 parts of 3-(2-aminoethyl)indole and dimethyl sulfoxide (10 mL), and heat at 80°C under reflux for 12 h. After the reaction is completed, pour the solution into 200 mL of deionized water to obtain an orange-red suspension. The suspension is divided into centrifuge tubes, centrifuged at high speed, and the supernatant is poured off to obtain an orange-red solid. The crude product is recrystallized with ethanol for 1-2 times, dried at 50°C for 6 h, and grinded to obtain an orange-red powder of BAT.

[0069] Preparation of anthracene derivative (ADO):

[0070]

[0071] Into a flask, 123.01 parts of potassium carbonate, 72.9 parts of diethanolamine, 3.61 parts of potassium iodide and 30 mL of DMSO were added and stirred thoroughly. Then 12.17 parts of 9-(bromomethyl)anthracene was dissolved in 30 mL of DMSO and put into the original reaction vessel, and 3-10 mL of DMSO was added to adjust the reaction rate. The reaction was carried out at 80°C for 4 h, and the obtained solution was poured into a large amount of water to obtain a suspension with light yellow flocculent substance. The suspension was filtered with a G4 type sand core funnel, washed with water, dried, recrystallized with ethanol, and finally dried in a vacuum chamber for 12 h to obtain a light yellow powder ADO.

[0072] Example 1

[0073] A fluorescent waterborne polyurethane with anti-counterfeiting function was synthesized according to the following steps:

[0074] (1) 50 parts of polycarbonate diol (PCDL1000) with a molecular weight of 1000 were vacuumed at 120°C for 2 h to remove water, and then the heating was turned off. When the temperature dropped to 80°C, 105 parts of isophorone diisocyanate (IPDI) was added and mixed and stirred under N2 atmosphere for 1 h, then 10 drops of catalyst dibutyltin dilaurate (DBTDL) was added, and the stirring was continued for 3 h to obtain a prepolymer.

[0075] (2) 3.75 parts of 1,4-butanediol (BDO), 0.25 parts of naphthalimide derivative (BAT) and 0.5 parts of anthracene derivative (ADO) were added to the prepolymer obtained in step (1), and a small amount of butanone was added for dilution, and the stirring was continued for 3 h to obtain an intermediate product containing fluorescent groups.

[0076] (3) The temperature was lowered to 70°C, and 30 parts of 2,2-bis(hydroxymethyl)butyric acid (DMBA) was added to the reaction solution obtained in step (2), and the reaction was carried out for 1.5 h to obtain an intermediate product containing hydrophilic groups.

[0077] (4) The temperature was lowered to 50°C again, and 20 parts of m-toluidine (m-T) was added, and the reaction was continued for 3 h to obtain an intermediate product containing hydrophilic groups.

[0078] (5) 30 parts of triethylamine was added to the reaction solution obtained in step (4) for neutralization, and the temperature was lowered to room temperature, and the stirring was continued for 0.5 h.

[0079] (6) 0.25 parts of europium nitrate and 5 parts of potassium acetate were dissolved in deionized water, after dissolution, the ion water solution was added into the system, the solid content of the emulsion was 38 wt%, the stirring speed of the stirrer was adjusted to 1500 r / min, the emulsion was emulsified at high speed for 0.5 h, the emulsion was obtained; the emulsion was poured into a mold, and placed at room temperature for 24 h, and then placed in a blast oven at 100°C for 5 h, to obtain a fluorescent waterborne polyurethane.

[0080] Comparative Example 1

[0081] The difference from Example 1 is that no potassium acetate is added in step (6).

[0082] Comparative Example 2

[0083] The difference from Example 1 is that no europium nitrate and potassium acetate are added in step (6).

[0084] Comparative Example 3

[0085] The difference from Comparative Example 2 is that in step (2), 3.25 parts of 1,4-butanediol (BDO), 0.25 parts of naphthalimide derivative (BAT) and 1 part of anthracene derivative (ADO) are added into the prepolymer obtained in step (1).

[0086] Comparative Example 4

[0087] The difference from Comparative Example 2 is that in step (2), 2.25 parts of 1,4-butanediol (BDO), 0.25 parts of naphthalimide derivative (BAT) and 2 parts of anthracene derivative (ADO) are added into the prepolymer obtained in step (1).

[0088] Comparative Example 5

[0089] The difference from Comparative Example 2 is that in step (2), 0.25 parts of 1,4-butanediol (BDO), 0.25 parts of naphthalimide derivative (BAT) and 4 parts of anthracene derivative (ADO) are added into the prepolymer obtained in step (1).

[0090] Comparative Example 1 is a fluorescent waterborne polyurethane emulsion without adding organic potassium salt, Comparative Examples 2-5 are fluorescent waterborne polyurethane emulsions without adding inorganic europium salt and organic potassium salt, only the ratio of naphthalimide derivative (BAT) and anthracene derivative (ADO) two fluorescent chain extenders is changed.

[0091] The mechanical properties of the polyurethanes obtained in the above examples and comparative examples were tested, and the results are shown in Table 1.

[0092] Table 1 Mechanical properties of each example and comparative example

[0093]

[0094] The emulsions obtained in the examples and comparative examples were coated on different substrates respectively, and then baked in a blast oven at 120°C for 0.1 h to obtain fluorescent waterborne polyurethane adhered to the substrates. The adhesion grade test was then performed.

[0095] Adhesion grade of each example and comparative example in Table 2 on different substrates

[0096]

[0097] By comparing the polyurethane obtained in Example 1 and Comparative Example, the tensile strength and pencil hardness of the polyurethane were greatly improved, indicating that the Eu 3+ and K + were introduced to construct a non-covalent physical crosslinking network based on double cation-π interaction. The introduction of cation-π interaction further increased the intermolecular force, promoted the aggregation of hard segments, and increased the degree of microphase separation, thereby greatly improving the mechanical properties of the polyurethane. However, the decrease in the mobility of the chain segments was not conducive to the self-repairing of the polyurethane, so the self-repairing efficiency of the polyurethane obtained in Example 1 was lower than that of the comparative example. The polyurethane obtained in all examples and comparative examples had a pencil hardness of HB or above, and the softness and hardness were moderate, which could provide clear and visible lines and patterns on the surface of various substrates, and was suitable for drawing, marking and other purposes. By comparing the polyurethanes obtained in Comparative Examples 2-5, it was found that with the increase of the content of the two fluorescent chain extenders, i.e. the increase of the rigid side chains, the tensile properties of the polyurethane were improved, and the pencil hardness was also improved, indicating that the increase of the rigid side chains in the system not only increased the hard segment content of the polymer, but also enhanced the interaction between the molecular chains, and the mobility of the chain segments of the polymer decreased, and the polyurethane showed better mechanical properties. The flexibility and adhesion of each example and comparative example on various substrates were good, indicating that the introduction of rigid groups and cations had little effect on the flexibility and adhesion of the polyurethane.

[0098] The fluorescent properties of the coating of Example 1 were evaluated after being placed at pH = 7, pH = 13, pH = 1, 100°C for 240 h, and after being placed in the open air for 15 d, and it was found that the fluorescence of the coating did not change significantly, as shown in Figure 2 , Figure 3 , indicating that the coating had good water resistance, acid and alkali resistance, heat resistance and light resistance, and the fluorescence stability was excellent.

[0099] As shown in Figure 4, by specific mold (black sample, hollow part can be made of ultraviolet light to control the polyurethane fixed area "input information"), under the irradiation of 365nm and 254nm ultraviolet light, can effectively input different information to the material. Under visible light, the example polyurethane will encrypt information, making the information completely unreadable. Under the irradiation of 254nm ultraviolet light, the information "E" can be effectively read, and then under the irradiation of 450nm blue light, the information "F" can be successfully read, and the effective information "EF" is finally obtained by combining the two information, realizing the double encryption of information.

[0100] The encrypted information input by 254nm ultraviolet light irradiation has extremely high read-only property, and under the irradiation of 365nm ultraviolet light, 450nm blue light and visible light, the information cannot be read, and only under the irradiation of 254nm ultraviolet light, the information is clearly output. Accordingly, as Figure 5 In (a), two information units were prepared, one of which was the example 1 polyurethane without any treatment, and the other was prepared into information unit by 254nm ultraviolet light irradiation. Two kinds of information units were composed into a certain information matrix to complete the input and composition of information. The two kinds of information units are identical under the irradiation of conventional anti-fake 365nm ultraviolet flashlight, but under the irradiation of 254nm ultraviolet light, the information "L" and "H" can be successfully decrypted and output, as shown in Figure 5 (b). By using this feature combined with the specific mold mentioned in Figure 4 (a), more complex pattern input can be completed, such as Figure 6 (a), the pattern of "dolphin" can be input to the polyurethane, and Figure 6 (b) shows more expression pattern of example 1 polyurethane sample.

[0101] The above examples are the preferred embodiments of the present application, but the embodiments of the present application are not limited by the above examples, and any changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principles of the present application shall be equivalent replacement methods, which are all included in the protection scope of the present application.

Claims

1. A method for preparing fluorescent waterborne polyurethane with anti-counterfeiting function, characterized in that, Includes the following steps: 1) Polycarbonate diol and diisocyanate are mixed and stirred, a catalyst is added, and stirring is continued to obtain a prepolymer; 2) Add a fluorescent chain extender and 1,4-butanediol to the prepolymer, stir, and obtain an intermediate product containing a fluorescent group; the fluorescent chain extender is a naphthalimide derivative BAT and an anthracene derivative ADO, with the following structural formula: ； The molar ratio of the naphthimide derivative to the anthracene derivative in the fluorescent chain extender is 0.25:0.5; 3) Add the hydrophilic chain extender to the intermediate product containing the fluorescent group, stir, and obtain the intermediate product containing the hydrophilic group; 4) Add benzidine to the intermediate product containing hydrophilic groups and stir; 5) Add triethylamine to the solution obtained in step 4) for neutralization; 6) Add inorganic europium salt, organic potassium salt and water to the solution obtained in step 5), stir to obtain an emulsion, solidify to obtain fluorescent waterborne polyurethane with anti-counterfeiting function; the molar ratio of inorganic europium salt, organic potassium salt and benzidine in step 4) is 0.25:1.25~10:

20.

2. The method for preparing the fluorescent waterborne polyurethane with anti-counterfeiting function as described in claim 1, characterized in that: Step 1) The polycarbonate diol is at least one of PCDL1000 and PCDL2000; Step 1) The diisocyanate is at least one of hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and toluene diisocyanate. Step 1) The molar ratio of diisocyanate to polycarbonate diol is 2~3:1; Step 1) The catalyst is at least one of stannous octoate, stannous oleate, and dibutyltin dilaurate; the ratio of the catalyst to polycarbonate diol is 1 drop: 4~6 mmol.

3. The preparation method of the fluorescent waterborne polyurethane with anti-counterfeiting function as described in claim 1, characterized in that: Step 1) The polycarbonate diol is dehydrated before mixing and stirring. Specifically, the polycarbonate diol is placed in a vacuum and dehydrated at 110~120 ℃ for 1~3 h to remove water and other small molecules from the polycarbonate diol for later use. Step 1) The mixing temperature is 80~90 ℃, the mixing time is 0.5~1.5 h, and the continued mixing time is 2.5~4 h; Step 1) The mixing and stirring are carried out under an N2 or Ar atmosphere.

4. The preparation method of the fluorescent waterborne polyurethane with anti-counterfeiting function as described in claim 3, characterized in that: The naphthalimide derivative was prepared by the following steps: Naphthalic anhydride and aminodiol were reacted at 80 °C for 12-24 h, and the solvent was removed, washed, and dried to obtain an intermediate. The intermediate was reacted with aminoindole in dimethyl sulfoxide at 80 °C for 12-24 h, and the mixture was centrifuged, impurities were removed, and dried to obtain a naphthalimide derivative. The anthracene derivative was prepared by the following steps: Potassium carbonate, anthracene bromide, and an alcohol amine were mixed and stirred in dimethyl sulfoxide and reacted at 80°C for 4-5 h. The mixture was then filtered, impurities removed, and dried to obtain a pale yellow anthracene derivative.

5. The method for preparing the fluorescent waterborne polyurethane with anti-counterfeiting function as described in claim 1, characterized in that: The molar ratio of the fluorescent chain extender, 1,4-butanediol, and polycarbonate diol in step 2) is 0.25~4.25:0.25~4.25:

50. The stirring time in step 2) is 2-3 hours.

6. The method for preparing the fluorescent waterborne polyurethane with anti-counterfeiting function as described in claim 1, characterized in that: Step 3) The hydrophilic chain extender is at least one of 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, and sodium ethylenediamine ethanesulfonate; The molar ratio of the hydrophilic chain extender in step 3) to the diisocyanate in step 1) is 1:10 to 2:5; Step 3) The stirring temperature is 70~80 ℃, and the stirring time is 1.5~2.5 h; Step 4) The benzidine is at least one of o-toluidine, meta-toluidine, and 3,3'-dimethoxybenzidine; The molar ratio of benzidine in step 4) to diisocyanate in step 1) is 1:10 to 2:5; Step 4) The stirring temperature is 40~50℃ and the stirring time is 2.5~3.5h.

7. The method for preparing the fluorescent waterborne polyurethane with anti-counterfeiting function as described in claim 1, characterized in that: The molar ratio of triethylamine in step 5) to the hydrophilic chain extender in step 3) is 1:1; Step 5) The neutralization temperature is room temperature; the stirring time for neutralization is 0.5~1h; Step 6) The inorganic europium salt is at least one of europium nitrate, europium carbonate, europium acetate, and europium sulfate; Step 6) The organic potassium salt includes at least one of potassium acetate, potassium propionate, potassium lactate, and potassium citrate; Step 6) The amount of water used is such that the solid content of the emulsion is 35wt%~40wt%. Step 6) The stirring temperature is 25~35℃; the stirring time is 0.5~1 h; Step 6) The curing process specifically involves coating the emulsion onto a substrate and curing it into shape, or pouring the emulsion into a mold and air-drying it.

8. A fluorescent aqueous polyurethane with anti-counterfeiting function prepared by the method according to any one of claims 1-7.

9. The application of the fluorescent waterborne polyurethane with anti-counterfeiting function as described in claim 8 in anti-counterfeiting labels, identification platforms, or smart displays.

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