Luminous cloth and preparation method thereof

Abstract

The invention relates to the technical field of light-emitting cloth and discloses light-emitting cloth and a preparation method thereof.The light-emitting cloth comprises a cloth substrate, a water-based ink layer, a conductive layer, an insulating layer, a light-emitting layer, an electrolytic layer and a color layer. The preparation method is characterized in that firstly, a salicylaldehyde Schiff base compound is synthesized through a Schiff base reaction, then the salicylaldehyde Schiff base compound and aniline are polymerized to prepare salicylaldehyde Schiff base modified polyaniline, and then the modified polyaniline is compounded with epoxy resin, silver powder and the like to prepare conductive silver paste resin. Salicylaldehyde Schiff base modified polyaniline serves as a structure-directing agent and an interface compatilizer, silver powder particles can be anchored through polar end groups of the salicylaldehyde Schiff base modified polyaniline, the dispersity is improved, an electron transmission channel can be constructed through a conductive framework, and the conductivity, adhesive force and flexibility of a conductive layer are remarkably improved. The outer insulating layer and the outer electrolytic layer are used for packaging, so that the prepared luminous cloth has excellent luminous performance, bending resistance and waterproof performance.

Description

Technical Field

[0001] This invention relates to the field of luminescent fabric technology, specifically to a luminescent fabric and its preparation method. Background Technology

[0002] As an important branch of smart textiles, flexible electroluminescent fabrics are increasingly in demand for applications in specific functional clothing and equipment. For example, in products such as cycling apparel, emergency rescue clothing, traffic warning clothing, and sports gloves, traditional reflective materials have limitations such as reliance on external light sources and passive warning effects. Actively luminescent fabrics, on the other hand, can significantly improve the visibility and safety of users in low-light environments. Currently, electroluminescence (EL) technology is one of the effective ways to achieve fabric luminescence. Its basic structure typically includes functional layers such as a conductive layer, a light-emitting layer, and a dielectric layer. However, the stable and reliable application of this technology to flexible fabric substrates faces many challenges.

[0003] First, the performance of the conductive layer, as a core component, is crucial. Currently, conductive silver paste is commonly used, which mainly consists of conductive fillers (such as silver powder) and binding resins (such as epoxy resin). However, silver powder is prone to agglomeration in polymer resins, leading to uneven dispersion and discontinuous conductive pathways, thus affecting conductivity and luminescence uniformity. Simultaneously, there is a mismatch between the inherent rigidity of epoxy resin and the flexibility of the fabric substrate; under repeated bending, the conductive layer is prone to cracking, leading to circuit failure. Furthermore, insufficient adhesion between the conductive layer and the fabric substrate is also a key issue affecting product durability. While simple conductive polymers, such as polyaniline, possess some conductivity, their dispersibility in commonly used resin matrices and their interfacial compatibility with inorganic conductive fillers (silver powder) are generally poor, making it difficult for them to exert a synergistic reinforcing effect on their own. Schiff bases are a class of organic compounds containing a characteristic imine group, formed by the condensation reaction of aldehydes or ketones with primary amines. The imine nitrogen atom has a lone pair of electrons, which can serve as a coordination site to form stable complexes with metal ions. This property makes them widely used in catalysis, materials science, and biomedicine.

[0004] Secondly, regarding the luminescent layer, zinc sulfide (ZnS), as a common electroluminescent material, exhibits luminous efficiency and stability highly dependent on the doped activator, such as copper (Cu). However, the performance of the luminescent material ultimately needs to be realized and maintained through an effective device structure. If the conductive layer is uneven or has excessively high impedance, it will directly lead to uneven electric field distribution in the luminescent layer, resulting in dark areas or insufficient brightness.

[0005] To achieve stable operation and impart color to the device, an insulating layer, an electrolytic layer, a water-based ink layer, and a color layer must be constructed sequentially. These functional layers not only need to have good interlayer adhesion and density to effectively prevent short circuits and block moisture, but also must maintain the same flexibility as the whole to ensure the normal operation and durability of the light-emitting device under bending conditions. Summary of the Invention

[0006] 1) Technical problems to be solved: To address the shortcomings of existing technologies, this invention provides a luminescent fabric and its preparation method, which solves the problems of uneven luminescence and durability in luminescent fabrics. It has better practical applications in sports equipment, such as cycling apparel, motorcycle apparel, emergency rescue apparel, traffic warning apparel, and sports gloves.

[0007] (II) Technical Solution: A method for preparing a luminescent fabric, the luminescent fabric comprising a fabric, a water-based ink, a conductive layer, an insulating layer, a luminescent layer, an electrolytic layer, and a colorant, wherein the conductive layer is silver paste resin, and the silver paste resin is prepared by the following method: S1. Add o-phenylenediamine and salicylaldehyde to the flask, stir and react at 25-30℃ for 5-10 min. Separate the crude product by column chromatography, eluting with a mixture of petroleum ether and ethyl acetate to obtain the salicylaldehyde Schiff base compound. The preparation reaction formula is: .

[0008] S2. Add salicylaldehyde Schiff base compound, aniline, and hydrochloric acid solution to a flask and stir until homogeneous. Slowly add ammonium persulfate and react at 25-30℃ for 20-24 hours. Filter, wash the initial product successively with hydrochloric acid solution and aqueous ethanol solution, and dry to obtain salicylaldehyde Schiff base modified polyaniline. The preparation reaction formula is:

[0009] S3. Add epoxy resin, diluent, salicylaldehyde Schiff base modified polyaniline, curing agent, and silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0010] Furthermore, the ratio of o-phenylenediamine to salicylaldehyde is (1-1.1) mol: 1 mol.

[0011] Furthermore, the ratio of salicylaldehyde Schiff base compound, aniline, and ammonium persulfate is (10-25) mol: (75-90) mol: (35-45) mol.

[0012] Furthermore, the concentration of the hydrochloric acid solution is 1-1.2 mol / L.

[0013] Furthermore, the ratio of epoxy resin, diluent, salicylaldehyde Schiff base modified polyaniline, curing agent, and silver powder is 10g:(3-5)g:(0.4-0.8)g:(0.1-0.4)g:(20-34)g.

[0014] Furthermore, the light-emitting layer is prepared by the following method: inorganic electroluminescent material, polyurethane binder, and organic solvent are mixed evenly to obtain the light-emitting layer material.

[0015] Furthermore, the luminescent material is any one or more of the following: zinc sulfide powder doped with copper activator, zinc sulfide powder doped with chlorine activator, zinc sulfide powder doped with manganese activator, strontium sulfide powder doped with copper activator, and calcium sulfide powder doped with europium activator; the organic solvent is any one of cyclohexanone, ethyl acetate, and isopropanol.

[0016] Furthermore, the ratio of inorganic electroluminescent material, polyurethane binder, and organic solvent is (50-70) g: 40 g: (8-12) g.

[0017] Furthermore, the preparation method of the luminescent material is as follows: the substrate is laid flat on the workbench and dusted; environmentally friendly water-based ink is printed; conductive silver paste resin is printed and heated and baked; insulating resin is printed in the area requiring insulation and heated and baked; luminescent material is printed and heated and baked; electrolytic dielectric material is printed and heated and baked; color layer is printed; the fabric is placed in an oven for heating and curing, and quality inspection is performed to obtain the luminescent fabric.

[0018] (III) Beneficial technical effects: This invention involves reacting o-phenylenediamine and salicylaldehyde with a Schiff base to obtain a salicylaldehyde Schiff base compound. This compound is then polymerized with aniline in hydrochloric acid solution to obtain salicylaldehyde Schiff base modified polyaniline, thereby introducing Schiff base groups into the polyaniline and improving its conductivity and dispersibility. The salicylaldehyde Schiff base modified polyaniline is then blended with epoxy resin and silver powder to obtain a conductive silver paste resin. Finally, a multi-layer printing process is used to sequentially form a water-based ink layer, a conductive layer, an insulating layer, a luminescent layer, an electrolytic layer, and a color layer on the fabric. After heat curing, a uniformly luminescent fabric is obtained. This material has excellent practical applications in cycling apparel, emergency rescue clothing, traffic warning clothing, and sports gloves.

[0019] The long-chain polymer structure of salicylaldehyde Schiff base-modified polyaniline in the silver paste resin prepared in this invention has a polar group at one end that can effectively adsorb or coat the surface of silver powder, while the polymer chain at the other end is compatible with epoxy resin, effectively anchoring the silver powder, preventing agglomeration, and ensuring its uniform dispersion in the epoxy resin. The conductive polyaniline skeleton of the salicylaldehyde Schiff base-modified polyaniline itself can construct efficient electron transport channels between silver powder particles, improving the conductivity of the silver paste resin and significantly enhancing its conductivity. Simultaneously, the salicylaldehyde Schiff base-modified polyaniline acts as an interface compatibilizer, connecting the silver powder, resin, and substrate, enhancing adhesion. Furthermore, the salicylaldehyde Schiff base-modified polyaniline effectively enhances the flexibility and density of the conductive layer. Combined with the outer insulating layer and electrolytic layer encapsulation, this ensures the stability of the conductive network when the luminescent fabric is bent and effectively blocks environmental moisture, thus achieving excellent bending resistance and waterproof performance. Detailed Implementation

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] The epoxy resin diluent listed below, model AGE, was purchased from Jinan Jibin Chemical Co., Ltd. The epoxy resin curing agent listed below, aminoethylpiperazine, was purchased from Jinan Chuangshi Chemical Co., Ltd. Example 1:

[0022] S1. Add 0.2 mol o-phenylenediamine and 0.2 mol salicylaldehyde to the flask, stir at 25°C for 10 min, separate the crude product by column chromatography, and elute with a mixed solution of petroleum ether and ethyl acetate to obtain salicylaldehyde Schiff base compound.

[0023] S2. Add 0.1 mol of salicylaldehyde Schiff base compound, 0.75 mol of aniline, and 2.5 L of 1 mol / L hydrochloric acid solution to a flask and stir until homogeneous. Slowly add 0.35 mol of ammonium persulfate and stir at 25 °C for 20 h. Filter and wash the initial product successively with hydrochloric acid solution and 90% ethanol aqueous solution. Dry to obtain salicylaldehyde Schiff base modified polyaniline.

[0024] S3. Add 1000g epoxy resin, 400g diluent AGE, 40g salicylaldehyde Schiff base modified polyaniline, 10g curing agent aminoethylpiperazine, and 2000g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0025] Example 2:

[0026] S1. Add 0.22 mol o-phenylenediamine and 0.2 mol salicylaldehyde to the flask, stir at 30°C for 5 min, separate the crude product by column chromatography, and elute with a mixed solution of petroleum ether and ethyl acetate to obtain salicylaldehyde Schiff base compound.

[0027] S2. Add 0.14 mol of salicylaldehyde Schiff base compound, 0.79 mol of aniline, and 2.5 L of 1 mol / L hydrochloric acid solution to a flask and stir until homogeneous. Slowly add 0.35 mol of ammonium persulfate and stir at 30 °C for 24 h. Filter and wash the initial product successively with hydrochloric acid solution and 90% ethanol aqueous solution. Dry to obtain salicylaldehyde Schiff base modified polyaniline.

[0028] S3. Add 1000g epoxy resin, 400g diluent AGE, 50g salicylaldehyde Schiff base modified polyaniline, 18g curing agent aminoethylpiperazine, and 2350g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0029] Example 3:

[0030] S1. Add 0.18 mol of salicylaldehyde Schiff base compound (obtained by the preparation method in Example 1), 0.83 mol of aniline, and 2.5 L of 1.1 mol / L hydrochloric acid solution to a flask and stir until homogeneous. Slowly add 0.4 mol of ammonium persulfate and stir at 25°C for 22 h. Filter and wash the initial product successively with hydrochloric acid solution and 90% (v / v) ethanol aqueous solution. Dry to obtain salicylaldehyde Schiff base modified polyaniline.

[0031] S2. Add 1000g epoxy resin, 500g diluent AGE, 60g salicylaldehyde Schiff base modified polyaniline, 26g curing agent aminoethylpiperazine, and 2700g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0032] Example 4:

[0033] S1. Add 0.22 mol of salicylaldehyde Schiff base compound (obtained by the preparation method in Example 1), 0.87 mol of aniline, and 2.5 L of 1.2 mol / L hydrochloric acid solution to a flask and stir until homogeneous. Slowly add 0.45 mol of ammonium persulfate and stir at 30°C for 24 h. Filter and wash the initial product successively with hydrochloric acid solution and 90% (v / v) ethanol aqueous solution. Dry to obtain salicylaldehyde Schiff base modified polyaniline.

[0034] S2. Add 1000g epoxy resin, 300g diluent AGE, 70g salicylaldehyde Schiff base modified polyaniline, 34g curing agent aminoethylpiperazine, and 3050g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0035] Example 5:

[0036] S1. Add 0.25 mol of salicylaldehyde Schiff base compound (obtained by the preparation method in Example 1), 0.9 mol of aniline, and 2.5 L of 1 mol / L hydrochloric acid solution to a flask and stir until homogeneous. Slowly add 0.45 mol of ammonium persulfate and stir at 30°C for 22 h. Filter and wash the initial product successively with hydrochloric acid solution and 90% ethanol aqueous solution. Dry to obtain salicylaldehyde Schiff base modified polyaniline.

[0037] S2. Add 1000g epoxy resin, 300g diluent AGE, 80g salicylaldehyde Schiff base modified polyaniline, 40g curing agent aminoethylpiperazine, and 3400g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0038] Comparative Example 1: The difference from Example 1 is that the polyaniline was not modified with salicylaldehyde Schiff base.

[0039] S1. Add 1000g epoxy resin, 400g diluent AGE, 10g curing agent aminoethylpiperazine, and 2000g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0040] Comparative Example 2: The difference from Example 1 is that polyaniline is used instead of salicylaldehyde Schiff base to modify polyaniline.

[0041] S1. Add 0.85 mol aniline and 2.5 L of 1 mol / L hydrochloric acid solution to a flask and stir until homogeneous. Slowly add 0.35 mol ammonium persulfate and stir at 25 °C for 20 h. Filter and wash the initial product successively with hydrochloric acid solution and 90% ethanol aqueous solution. Dry to obtain polyaniline.

[0042] S2. Add 1000g epoxy resin, 400g diluent AGE, 40g polyaniline, 10g curing agent aminoethylpiperazine, and 2000g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0043] Comparative Example 3: The difference from Example 1 is that the salicylaldehyde Schiff base compound is used instead of the salicylaldehyde Schiff base to modify polyaniline.

[0044] S1. Add 0.2 mol o-phenylenediamine and 0.2 mol salicylaldehyde to the flask, stir at 25°C for 10 min, separate the crude product by column chromatography, and elute with a mixed solution of petroleum ether and ethyl acetate to obtain salicylaldehyde Schiff base compound.

[0045] S2. Add 1000g epoxy resin, 400g diluent AGE, 40g salicylaldehyde Schiff base compound, 10g curing agent aminoethylpiperazine, and 2000g silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

[0046] The volume resistivity of silver paste resin was determined according to the method in GJB 548B-2005.

[0047] The adhesion of silver paste resin coatings was determined according to the method of GB / T 9286-2021.

[0048] Table 1 Performance determination of silver paste resin

[0049] The long-chain polymer structure of salicylaldehyde Schiff base modified polyaniline in the silver paste resin prepared in Examples 1-5 has a polar group at one end that can effectively adsorb or coat the surface of silver powder, while the polymer chain at the other end is compatible with epoxy resin, effectively anchoring the silver powder, preventing agglomeration, and ensuring its uniform dispersion in epoxy resin. The conductive polyaniline skeleton of salicylaldehyde Schiff base modified polyaniline can build efficient electron transport channels between silver powder particles, improving the conductivity of silver paste resin and significantly enhancing conductivity. At the same time, salicylaldehyde Schiff base modified polyaniline acts as an interface compatibilizer, connecting silver powder, resin, and substrate, enhancing adhesion.

[0050] Compared with Example 1, Comparative Example 1 prepared silver paste resin without salicylaldehyde Schiff base modified polyaniline. Due to the lack of the long-chain polymer structure of salicylaldehyde Schiff base modified polyaniline, the silver powder agglomerated in the epoxy resin, resulting in poor dispersibility and inability to form a uniform conductive network. The conductivity and adhesion were both poor.

[0051] Compared with Example 1, Comparative Example 2 used polyaniline to replace salicylaldehyde Schiff base to prepare silver paste resin. The resin had poor dispersibility and could not effectively anchor silver powder, resulting in agglomeration of both itself and silver powder, and failed to improve dispersibility. At the same time, it lacked strong interfacial binding functional groups and could not act as a compatibilizer to improve adhesion.

[0052] Compared with Example 1, Comparative Example 3 used salicylaldehyde Schiff base compound to modify polyaniline to prepare silver paste resin instead of salicylaldehyde Schiff base compound. However, salicylaldehyde Schiff base compound is an insulator and cannot build efficient electron transport channels between silver powder particles, resulting in low conductivity.

[0053] The present invention also provides the following embodiment, a method for preparing luminescent fabric.

[0054] Example 6: Step (1): Mix 500g of zinc sulfide powder with copper activator, 40g of polyurethane binder and 8g of ethyl acetate evenly to obtain the light-emitting layer material.

[0055] Step (2): Lay the printing fabric flat on the workbench and remove dust; print environmentally friendly water-based ink 3 times; print conductive silver paste resin 2 times, heat to 80℃ and bake for 60 minutes; print insulating resin 1 time on the area requiring insulation, heat to 80℃ and bake for 80 minutes; print luminescent material 2 times, heat to 50℃ and bake for 20 minutes; print electrolytic dielectric material 2 times, heat to 80℃ and bake for 30 minutes; print color layer; put the whole thing into a sealed oven and heat to 80℃ for 3 hours to cure, and inspect for quality to obtain luminescent fabric.

[0056] Example 7: Step (1): Mix 700g of zinc sulfide powder with chlorine activator, 40g of polyurethane binder and 12g of cyclohexanone evenly to obtain the light-emitting layer material.

[0057] Step (2): Lay the printing fabric flat on the workbench and remove dust; print environmentally friendly water-based ink 5 times; print conductive silver paste resin 2 times, heat to 70℃ and bake for 80 minutes; print insulating resin 2 times in the area requiring insulation, heat to 70℃ and bake for 60 minutes; print electrolytic dielectric material 1 time, heat to 90℃ and bake for 20 minutes; print color layer; put the whole thing into a sealed oven and heat to 60℃ for 5 hours to cure, and inspect for quality to obtain luminescent fabric.

[0058] The present invention has been described in detail above with reference to the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for preparing a luminescent fabric, characterized in that, The luminescent fabric comprises fabric, water-based ink, conductive layer, insulating layer, luminescent layer, electrolytic layer, and color. The conductive layer is silver paste resin, which is prepared by the following method: S1. Add salicylaldehyde Schiff base compound, aniline, and hydrochloric acid solution to a flask and stir until homogeneous. Slowly add ammonium persulfate and stir at 25-30℃ for 20-24 hours. Filter and wash the initial product with hydrochloric acid solution and ethanol aqueous solution in sequence. Dry to obtain salicylaldehyde Schiff base modified polyaniline. S2. Add epoxy resin, diluent, salicylaldehyde Schiff base modified polyaniline, curing agent, and silver powder to a beaker and stir until homogeneous to obtain silver paste resin.

2. The method for preparing the luminescent fabric according to claim 1, characterized in that, The ratio of the salicylaldehyde Schiff base compound, aniline, and ammonium persulfate is (10-25) mol: (75-90) mol: (35-45) mol.

3. The method for preparing the luminescent fabric according to claim 1, characterized in that, The concentration of the hydrochloric acid solution is 1-1.2 mol / L.

4. The method for preparing the luminescent fabric according to claim 1, characterized in that, The ratio of epoxy resin, diluent, salicylaldehyde Schiff base modified polyaniline, curing agent, and silver powder is 10g:(3-5)g:(0.4-0.8)g:(0.1-0.4)g:(20-34)g.

5. The method for preparing the luminescent fabric according to claim 1, characterized in that, The salicylaldehyde Schiff base compound was prepared by the following method: o-phenylenediamine and salicylaldehyde were added to a flask and stirred at 25-30°C for 5-10 min. The crude product was separated by column chromatography and eluted with a mixed solution of petroleum ether and ethyl acetate to obtain the salicylaldehyde Schiff base compound.

6. The method for preparing the luminescent fabric according to claim 5, characterized in that, The ratio of o-phenylenediamine to salicylaldehyde is (1-1.1) mol: 1 mol.

7. The method for preparing the luminescent fabric according to claim 1, characterized in that, The light-emitting layer is prepared by the following method: inorganic electroluminescent material, polyurethane binder and organic solvent are mixed evenly to obtain the light-emitting layer material.

8. The method for preparing the luminescent fabric according to claim 7, characterized in that, The luminescent material is any one or more of the following: zinc sulfide powder doped with copper activator, zinc sulfide powder doped with chlorine activator, zinc sulfide powder doped with manganese activator, strontium sulfide powder doped with copper activator, and calcium sulfide powder doped with europium activator; the organic solvent is any one of cyclohexanone, ethyl acetate, and isopropanol.

9. The method for preparing the luminescent fabric according to claim 7, characterized in that, The ratio of the inorganic electroluminescent material, polyurethane binder, and organic solvent is (50-70)g:40g:(8-12)g.

10. The method for preparing the luminescent fabric according to claim 1, characterized in that, The method for preparing the luminescent material is as follows: the substrate is laid flat on the workbench and dusted; environmentally friendly water-based ink is printed; conductive silver paste resin is printed and heated and baked; insulating resin is printed in the area requiring insulation and heated and baked; luminescent material is printed and heated and baked; electrolytic dielectric material is printed and heated and baked; color layer is printed; the fabric is placed in an oven for heating and curing, and quality inspection is performed to obtain the luminescent fabric.

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