Use of a tetraphenylstyrene derivative in inkless writing materials

Abstract

The application discloses application of a tetraphenyl ethene derivative in inkless writing material, and comprises a base material and a tetraphenyl ethene derivative distributed on the base material, wherein the tetraphenyl ethene derivative comprises a compound as shown in the following formula: The tetraphenyl ethene derivative with the structure of the application is distributed in the base material, and under the action of force, the tetraphenyl ethene derivative generates ultraviolet excitable cyan fluorescence, which not only enriches the inkless writing material, and better satisfies the creative and personalized needs of people for writing, meanwhile, the material of the application scheme can realize writing through scraping, and can restore to the initial state after fumigation, the operation is simple, the repeated writing effect is good, and the material has a good application prospect in the fields of anti-fake and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new materials, in particular to application of a tetraphenyl ethylene derivative in inkless writing materials. BACKGROUND

[0002] Inkless writing technology is an innovative writing method that abandons traditional ink or refill and achieves writing effect through other means. Inkless writing technology has broad application prospects in the field of anti-counterfeiting. Traditional anti-counterfeiting technologies often rely on the special properties of ink or the addition of markers, but these methods are easy to be imitated or tampered with. In contrast, inkless writing technology can achieve anti-counterfeiting effect through digitization or other innovative ways, providing higher security and reliability.

[0003] Currently, some inkless writing technologies have been applied in the field of anti-counterfeiting, such as electronic anti-counterfeiting labels and inkless printing. These technologies use special inkless writing materials or devices to achieve unique identification codes, invisible ink or erasable writing functions to provide anti-counterfeiting protection and traceability. However, existing writing materials have defects such as irreversibility, which cannot be changed or reversed once written, limiting the flexibility and reusability of writing, especially for scenarios that require frequent modification or update of information. At the same time, the preparation cost of some inkless writing materials is relatively high, and if they cannot be reused, it may greatly affect the feasibility of their large-scale application. Reducing material cost is crucial to promote the popularization and commercialization of inkless writing technology. In addition, the existing writing materials are limited in variety, which is difficult to meet people's creative and personalized needs, such as the existing writing materials only provide black and blue colors without cyan color, and the writing methods are relatively single.

[0004] Therefore, developing new inkless writing materials is of great significance to the field of inkless writing technology and anti-counterfeiting. SUMMARY

[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes application of a tetraphenyl ethylene derivative in inkless writing materials, which has good reversibility and also enriches the variety of inkless writing materials.

[0006] According to one aspect of the present application, an inkless writing material is proposed, comprising a base material and a tetraphenyl ethylene derivative distributed on the base material, the tetraphenyl ethylene derivative comprising a compound as shown in the following formula:

[0007]

[0008] According to a preferred embodiment of the present application, at least the following advantages are achieved: by distributing the tetraphenyl ethylene derivative of the structure of the present application in the base material, it produces a UV-excitable cyan fluorescence under force, which not only enriches the inkless writing material, and better meets people's creative and personalized needs for writing, but also realizes writing by scratching and restores to the initial state after fumigation, is easy to operate, has good repeated writing effect, saves inkless writing cost, and has good application prospect in the field of anti-counterfeiting.

[0009] In some embodiments of the present application, the base material can be paper, such as filter paper, etc., or any other commonly used material in the art, such as wood, plastic, glass sheet, silicon sheet, flat metal sheet, protective layer (such as hydrogel), silk fiber film, spider silk film, blackboard, wall surface, plastic, rubber or ceramic, etc.

[0010] According to another aspect of the present application, an application of a tetraphenyl ethylene derivative in preparing an inkless writing material is provided, wherein the tetraphenyl ethylene derivative comprises a compound with the following structure:

[0011]

[0012] According to the application of a preferred embodiment of the present application, at least the following advantages are achieved: the initial powder of the tetraphenyl ethylene derivative of the structure of the present application only weakly emits light, but emits bright cyan light under a UV lamp when a mechanical force is applied thereto, and restores to the initial emission state after solvent fumigation, has good reversibility, can be repeatedly used, and has good application prospect in the field of inkless writing. The cost of the new material of the present application is about 320 yuan per gram, and the price of other similar performance new materials is about 1500 yuan per gram. The cost of the material of the present application is reduced by nearly 80%.

[0013] According to still another aspect of the present application, a preparation method of an inkless writing material is provided, comprising the following steps:

[0014] The tetraphenyl ethylene derivative is applied to the surface of the base material, and the application comprises at least one of smearing, coating, dipping and electrospinning. The force-responsive luminescent material tetraphenyl ethylene derivative is applied to the surface of the base material by coating, dipping or electrospinning process, which is easy to operate.

[0015] In some preferred embodiments of the present application, the preparation method further comprises a preparation process of the tetraphenyl ethylene derivative, specifically comprising:

[0016] (1) Synthesis of intermediate tetraphenyl ethylene aldehyde (TPEA):

[0017] Mixing triphenylbromovinyl and 4-formylphenylboronic acid under protective atmosphere (such as nitrogen or inert gas), then adding tetrahydrofuran (THF), carbonate solution (preferably potassium carbonate), tetrabutylammonium bromide (TBAB), stirring at room temperature (25±5℃, preferably 25℃) and passing protective gas (about half an hour), then adding Pd(PPh3)4, heating to 90±10℃, and reacting for 24±2h to obtain.

[0018]

[0019] (2) Synthesis of target product

[0020] After TPEA is fully dissolved, adding anhydrous magnesium chloride and catalyst acetic acid, and continuing to stir at 90±10℃ for 10±5min, then adding urea and 1,3-cyclohexanedione into a three-neck flask, and reacting for 24±2h to obtain.

[0021]

[0022] According to another aspect of the present application, the above-mentioned inkless writing material is applied in inkless writing, inkless information data storage, repeated writing, anti-counterfeiting and encryption.

[0023] According to another aspect of the present application, a repeated use method of the inkless writing material is provided, comprising the following steps:

[0024] Applying force on the surface of the above-mentioned inkless writing material to form writing content, exciting by ultraviolet light, and removing the writing content by solvent fumigation. In some preferred embodiments of the present application, the force includes mechanical force such as scraping, etc.

[0025] In some more preferred embodiments of the present application, the wavelength of the ultraviolet light is 320-405nm; preferably 345nm-385nm; more preferably 365nm.

[0026] In some preferred embodiments of the present application, the solvent used in fumigation is at least one of ethanol, dichloromethane, tetrahydrofuran, chloroform or acetone. Any volatile solvent can be used. The force-induced luminescence of the material according to the present application solution has reversibility, and after fumigation, it returns to the initial emission state, thereby realizing repeated use and achieving fluorescent switch switching effect. Especially for packaging materials, anti-counterfeiting and encryption fields, this property can greatly improve economic benefits.

[0027] According to another aspect of the present application, a repeatable writing medium is provided, which comprises the above-mentioned inkless writing material.

[0028] In some preferred embodiments of the present application, the repeatable writing medium is repeatable writing paper.

[0029] Other features and advantages of the present application will be set forth in the description that follows, and in part will be apparent from the description, or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0030] The above and / or additional aspects and advantages of the present application will become apparent and be more readily understood through consideration of the following description, taken in conjunction with the accompanying drawings, in which:

[0031] Figure 1 is the performance effect test chart of the tetraphenyl ethene derivative powder prepared in Example 1 of the present application; a) the molecular structure of TPE-HXD, b) the corresponding fluorescence spectrum change, c) the fluorescence pictures under different treatments, wherein, ground represents grinding, fumed represents fuming;

[0032] Figure 2 is the inkless writing recycling test effect chart in Example 2 of the present application; a) the fluorescence effect under ultraviolet excitation before inkless writing and after solvent fuming; b-d) are the effect charts during inkless writing.

[0033] Figure 3 is the result chart before and after writing for 48 hours in Example 2 of the present application;

[0034] Figure 4 is the recoverable performance effect test chart in Example 2 of the present application. DETAILED DESCRIPTION

[0035] The concept and the technical effects of the present application will be described clearly and completely in combination with the embodiments, so as to fully understand the purpose, features and effects of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application. The test methods used in the embodiments are conventional methods unless otherwise specified. The materials, reagents and the like used in the embodiments are commercially available unless otherwise specified. The same parameters in each embodiment have the same values unless otherwise specified. The following described embodiments are exemplary and are used to explain the present application, and cannot be understood as limiting the present application.

[0036] In the description of the application, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the application. In the description of the application, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in one or more embodiments or examples.

[0037] Example 1

[0038] In this example, an inkless writing material is prepared, and the specific process is as follows:

[0039] 1) Preparation of tetraphenyl ethene derivative

[0040] (1) Synthesis of intermediate tetraphenyl ethene aldehyde

[0041] Triphenyl bromo ethene (3.35 g, 10 mmol) and 4-formyl phenyl boronic acid (1.50 g, 10 mmol) were added into a three-necked flask under N2 atmosphere, then tetrahydrofuran (THF) 50 mL, 2 mol / L aqueous potassium carbonate solution 18 mL, tetrabutyl ammonium bromide (TBAB) (0.32 g, 1.0 mmol) were added, and finally Pd(PPh3)4(0.010 g, 8.7 x 10 -3 mmol) was added, and the temperature was raised to 90 °C for 24 h. The reaction solution was extracted with ethyl acetate three times, and the organic layer was dried with anhydrous sodium sulfate, and the solvent was removed by rotary evaporation under reduced pressure, and the product was purified by silica gel column chromatography, and the eluent was a mixture of dichloromethane and n-hexane with a volume ratio of 1:2. The product was obtained in a yield of 97% (3.25 g).

[0042]

[0043] (2) Synthesis of target product

[0044] Synthesis of 9-(4-(1,2,2-triphenylvinyl)phenyl)-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione

[0045] TPEA (0.361 g, 1 mmol) and 30 mL of absolute ethanol were added into a three-necked flask and heated at 75℃ with sufficient stirring. After TPEA was dissolved completely, anhydrous magnesium chloride (0.019 g, 0.2 mmol) and catalyst acetic acid (9 mL, 30% of ethanol) were added and heated and stirred for 10 min. Then urea (0.06 g, 1 mmol) and 1,3-cyclohexanedione (0.196 g, 2 mmol) were added and reacted for 24 h. Filtration was performed and the residue was washed with ethanol for 3 times to obtain white powder (0.44 g, 80%).

[0046]

[0047] The tetraphenylethene derivative prepared by the scheme of the embodiment of the present application is consistent with the theoretical structure, which is confirmed by nuclear magnetic and mass spectrometry.

[0048] 2) The tetraphenylethene derivative powder prepared by the above operation was evenly applied on the filter paper as the base material.

[0049] The force-induced light response effect of the tetraphenylethene derivative powder prepared by the above operation was detected, and the results are shown in Figure 1 Generally, the AIE compound often shows strong PL (Photoluminescence) in the aggregated state or solid state. However, the initial powder of the TPE-HXD compound (the structural formula is shown in Figure 1 a) obtained by the above operation emits weak fluorescence, and the fluorescence quantum efficiency is only 4.37%. Surprisingly, when the initial powder is scraped with a spoon, bright cyan light is emitted under the 365 nm ultraviolet lamp, and the fluorescence quantum efficiency is 30.08%. Figure 1 b) is the corresponding fluorescence spectrum, and it can be seen from the figure that the emission spectrum of the ground powder is obviously red-shifted, and the fluorescence intensity is obviously enhanced.

[0050] Further, the emission state can be restored to the initial state after dichloromethane vapor fumigation, and the reversibility is good. As shown in Figure 1 c), the whole fluorescence change process can be clearly and quickly distinguished by the naked eye.

[0051] The above experimental results show that the tetraphenylethene derivative used in the inkless writing material of the scheme of the present application not only can realize inkless writing, but also can emit novel cyan light under the action of external force, which enriches the types of inkless writing materials. In addition, it can be reused with good reversibility, which reduces the cost of writing. At the same time, the preparation process is simple, so the inkless writing material prepared by the scheme of the present application has good application prospect in inkless writing, inkless information data storage, repeated writing, anti-counterfeiting or encryption. The material prepared by the above operation can be used as repeated writing paper.

[0052] Example 2

[0053] This example provides a method for reusing the inkless writing material, the specific process is:

[0054] The inkless writing material prepared in the above example is used for repeated writing. Under the observation of 365 nm ultraviolet lamp, as shown in Figure 2 a), it can be seen from the figure that the inkless writing material almost does not emit fluorescence. When the "AIEWYU" characters are written on the paper with the tip of a medicine spoon, the scraped area immediately becomes bright cyan, as shown in Figure 2 b)-d), and then the rewritten paper is fumigated with dichloromethane steam, and then returns to the initial state, and the observation result is consistent with Figure 2 a).

[0055] In addition, another paper is used for writing test stability, and after being placed for 48 hours after writing, the observation is as shown in Figure 3 , it can be seen from the figure that the fluorescence intensity has no change, which indicates that the material of the present application has good stability.

[0056] Further, the reuse effect is also tested, and the result of repeated writing 5 times is as shown in Figure 4 , it can be seen from the figure that the repeated writing also remains good recoverability. The slight difference in fluorescence intensity in the figure is related to the writing intensity and the amount of pressing to the powder when writing.

[0057] Therefore, it is shown that the inkless writing material of the present application has good reusability, and has great application prospect in the field of anti-counterfeiting.

[0058] The above has made a detailed description of the embodiments of the present application, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge range of ordinary skilled in the art without departing from the purpose of the present application.

Claims

1. An inkless writing material, characterized by: A substrate material and a tetraphenylstilbene derivative distributed on the substrate material, the tetraphenylstilbene derivative comprising a compound of the following formula: ； The substrate material is paper, wood, plastic, glass, silicon, metal, hydrogel, silk fiber, spider silk, blackboard, wall, rubber, or ceramic.

2. Use of a tetraphenylstilbene derivative for the preparation of an inkless writing material, characterized in that: The tetraphenylstilbene derivative comprises a compound of the following formula: 。 3. The method of making an inkless writing material according to claim 1, wherein: The method comprises the following steps: Applying the tetraphenylstilbene derivative on the surface of the substrate material, the applying comprising at least one of smearing, coating, dipping, and electrospinning.

4. The inkless writing material of claim 1 is used in inkless writing, inkless information data storage, repeated writing, anti-counterfeiting, or encryption.

5. The method of claim 1, wherein the inkless writing material is a paper. The method comprises the following steps: Applying a force on the surface of the inkless writing material to form a writing content, and removing the writing content by fumigation.

6. The method of claim 5, wherein: The force is a mechanical force.

7. The method of claim 6, wherein: The mechanical force is scraping.

8. The method of claim 5, wherein: The method of recycling further comprises the step of viewing the writing content after excitation by ultraviolet light.

9. The method of claim 8, wherein: The wavelength of the ultraviolet light is 320-405 nm.

10. The method of claim 8, wherein: The wavelength of the ultraviolet light is 345 nm-385 nm.

11. The method of claim 8, wherein: The wavelength of the ultraviolet light is 365 nm.

12. The method of recycling according to any one of claims 5 to 11, wherein: The solvent used in the fumigation is at least one of dichloromethane, tetrahydrofuran, chloroform, or acetone.

13. A rewritable medium, characterized by: The medium comprises the inkless writing material of claim 1.

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