A method for preparing a microfiber velvet surface with conductive and flame-retardant properties

Abstract

This invention discloses a method for preparing a microfiber suede surface with conductive and flame-retardant properties. During the processing of island-type microfiber nonwoven fabric, amorphous nano-aluminum hydroxide or magnesium hydroxide is added as a functional filler to the impregnation slurry. Subsequently, the nonwoven fabric is impregnated with this slurry and then sequentially undergoes coagulation in a coagulation bath, weight reduction, drying, and brushing processes to finally obtain the functionalized microfiber suede surface. This invention, through the addition of nano-amorphous aluminum hydroxide / magnesium hydroxide, utilizes the large number of unbonded electrons or empty orbitals inherent in the three-dimensional amorphous structure to effectively construct a conductive network / pathway, thereby significantly reducing the surface resistance of the material; simultaneously, aluminum hydroxide or magnesium hydroxide itself has flame-retardant properties. Therefore, the microfiber suede surface prepared by this method can simultaneously achieve excellent antistatic (conductive) and flame-retardant properties.

Description

Technical Field

[0001] This invention belongs to the field of preparation technology of island-type microfiber suede, specifically relating to a method for preparing microfiber suede with conductive and flame-retardant properties. Background Technology

[0002] Microfiber suede, with its delicate texture and suede-like appearance, is widely used in high-end apparel, home furnishings, and automotive interiors. As its applications expand, the market is demanding higher functionality, especially in specific applications such as automotive interiors, where durable antistatic (conductive) and flame-retardant properties are becoming increasingly important.

[0003] Currently, the common method for imparting functionality to microfiber suede is mainly post-processing, which involves applying antistatic agents or flame retardants through coating or impregnation after the base fabric is made. However, such post-processing methods have significant limitations: firstly, antistatic agents are easily lost due to migration, volatilization, or washing, leading to poor functional durability; secondly, many organic flame retardants may pose environmental problems. Therefore, developing a more environmentally friendly preparation method that can firmly integrate conductive and flame-retardant functions within the material has significant technological value and application prospects. Summary of the Invention

[0004] To address the above problems, the present invention aims to provide a method for preparing a microfiber velvet surface with conductive and flame-retardant properties.

[0005] The specific technical solution is as follows: A method for preparing a microfiber velvet surface with conductive and flame-retardant properties includes the following steps: preparing island-type microfiber nonwoven fabric and slurry; immersing the island-type microfiber nonwoven fabric in the slurry; scraping the top and bottom surfaces with a liquid cutter; coagulating in a coagulation bath; reducing the amount extracted; drying; and brushing to obtain a microfiber velvet surface with conductive and flame-retardant properties. The slurry is composed of polyurethane resin, nano-amorphous aluminum hydroxide or magnesium hydroxide, and solvent DMF.

[0006] Furthermore, the sea phase of the island-type microfiber nonwoven fabric is PE or COPET, and the island phase is PA or PET.

[0007] Furthermore, the mass percentage of polyurethane resin in the slurry is 10%~25%, the mass percentage of nano-amorphous aluminum hydroxide or magnesium hydroxide is 5%~40%, the particle size D50 of nano-amorphous aluminum hydroxide or magnesium hydroxide is controlled in the range of 1~800nm, the modulus of polyurethane resin is 30~250, and the viscosity of the overall slurry is controlled between 1000~8000 mPa / s.

[0008] Furthermore, the coagulation bath is a mixed solution of DMF and water, with DMF accounting for 10% to 50% of the mass of the mixed solution system, and the coagulation bath temperature is 30℃ to 60℃.

[0009] Furthermore, the reduction extraction is either toluene reduction extraction or alkali reduction extraction.

[0010] Furthermore, the drying temperature is 90-180℃, and the drying time is 3-8 minutes.

[0011] Furthermore, the sandpaper used for sanding is 180-600 grit, the grinding depth is 0.05-0.1 mm, and the sandpaper linear speed for sanding is 400-1100 m / min.

[0012] The beneficial effects of this invention are as follows: This method introduces nano-amorphous aluminum hydroxide or magnesium hydroxide into the impregnation slurry of island-type microfiber nonwoven fabric, enabling the final microfiber velvet surface to simultaneously achieve excellent conductivity (antistatic properties) and flame retardancy. Compared with techniques that add antistatic agents or flame retardants through post-processing, the method of this invention has the following significant advantages: 1) Performance Integration and Enhancement: By directly adding functional nanoparticles to the matrix resin, the intrinsic integration of conductivity and flame retardancy is achieved. The conductivity is achieved by adding nano-amorphous aluminum hydroxide / magnesium hydroxide, which utilizes the large number of unbonded electrons or empty orbitals inherent in the three-dimensional amorphous structure to effectively construct a conductive network / pathway, thereby significantly reducing the surface resistance of the material. The flame retardancy comes directly from the endothermic decomposition and water vapor release properties of aluminum hydroxide / magnesium hydroxide itself.

[0013] 2) Durable and robust performance: Since the functional nanoparticles are uniformly dispersed and embedded in the polyurethane resin matrix, rather than being attached to the material surface through post-processing, their conductive and flame-retardant functions are not easily migrated, detached, or lost due to use, friction, or washing, ensuring the long-term effectiveness and stability of the functions.

[0014] 3) Environmental friendliness: Using inorganic aluminum hydroxide or magnesium hydroxide as functional additives is more environmentally friendly than some organic flame retardants or antistatic agents, and is more in line with current requirements for environmentally friendly materials. Detailed Implementation

[0015] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0016] Example 1

[0017] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 1.5 mm was selected. A polyurethane resin with a mass ratio of 15% and a modulus of 30 was used as the impregnation slurry. The solvent was DMF, without the addition of amorphous aluminum hydroxide or magnesium hydroxide. The slurry viscosity was 1200 mPa / s. After impregnating the nonwoven fabric with this slurry, the top and bottom surfaces were smoothed with a cutting blade. The fabric was then placed in a coagulation bath with a DMF concentration of 30% (a mixed solution of DMF and water at 40°C) for coagulation. Subsequently, it was subjected to weight reduction extraction in toluene and dried at 150°C (5 min). Finally, it was sanded with 400-grit sandpaper at a sanding speed of 450 m / min and a cutting depth of 0.1 mm to create a microfiber velvet surface. Finally, its electrical resistance and flame retardancy were tested. The results showed an electrical resistance level of 10... 11 On the order of Ω / m 2 (Ohms per square meter), flame retardancy is D-150mm / min.

[0018] Example 2

[0019] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 1.5 mm was selected. Amorphous aluminum hydroxide with a particle size D50 of 150 nm and a modulus of 30 (15% by weight) was mixed with DMF (3% by weight of amorphous aluminum hydroxide) as the solvent. The slurry viscosity was 1300 mPa / s. The nonwoven fabric was impregnated with this mixture. After smoothing both sides with a cutting knife, it was placed in a coagulation bath with a DMF concentration of 30% (a mixture of DMF and water at 40°C) for coagulation. Subsequently, it was subjected to weight reduction extraction in toluene and dried at 150°C (5 min). Finally, it was brushed with 400-grit sandpaper at a brushing speed of 450 m / min and a cutting depth of 0.1 mm to create a microfiber velvet surface. Finally, its electrical resistance and flame retardancy were tested. The results showed an electrical resistance level of 10... 10 On the order of Ω / m 2 (Ohms per square meter), flame retardancy is D-85mm / min.

[0020] Example 3

[0021] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 1.5mm was selected. Amorphous aluminum hydroxide with a particle size D50 of 150nm and a modulus of 30 polyurethane resin with a mass ratio of 15% was used as the impregnating agent. The amorphous aluminum hydroxide had a mass ratio of 42% and a slurry viscosity of 13000mPa / s. The nonwoven fabric was impregnated with the slurry. It was found that the viscosity was too high and the impregnation was poor, so it was impossible to make the corresponding microfiber velvet surface.

[0022] Example 4

[0023] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 1.5 mm was selected. An impregnation slurry with a viscosity of 2000 mPa / s was prepared using 15% polyurethane resin (modulus 30 by mass) and 20% amorphous aluminum hydroxide (D50 particle size 150 nm) as solvent (DMF). The nonwoven fabric was then impregnated with this slurry. After smoothing both sides with a cutting blade, the fabric was placed in a coagulation bath (a mixture of DMF and water at 40°C) with a DMF concentration of 30% for coagulation. Subsequently, the fabric was subjected to weight reduction extraction in toluene and dried at 150°C for 5 min. Finally, it was brushed with 400-grit sandpaper at a brushing speed of 450 m / min and a cutting depth of 0.1 mm to create a microfiber velvet surface. The resistivity and flame retardancy were then tested, and the results showed a resistivity level of 10. 5 On the order of Ω / m 2 (Ohms per square meter), flame retardant rating is A-0.

[0024] Example 5

[0025] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 1.8 mm was selected. An impregnation slurry with a viscosity of 1800 mPa / s was prepared using 10% polyurethane resin (modulus 60) and 20% amorphous aluminum hydroxide (D50 particle size 250 nm) as solvent (DMF). The nonwoven fabric was then impregnated with this slurry. After smoothing both sides with a cutting blade, the fabric was placed in a coagulation bath (a mixture of DMF and water at 40°C) with a DMF concentration of 30% for coagulation. Subsequently, the fabric was subjected to weight reduction extraction in toluene and dried at 150°C for 5 min. Finally, it was brushed with 400-grit sandpaper at a brushing speed of 450 m / min and a cutting depth of 0.1 mm to create a microfiber velvet surface. Electrical resistance and flame retardancy tests were then performed, showing an electrical resistance level of 1×10⁻⁶. 5 On the order of Ω / m 2 (Ohms per square meter), flame retardant rating is A-0.

[0026] Example 6

[0027] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 1.8 mm was selected. An impregnation slurry with a viscosity of 2500 mPa / s was prepared using polyurethane resin (18% by mass, modulus 90) and amorphous aluminum hydroxide (D50 particle size 450 nm) as solvent (DMF, 25% by mass). The nonwoven fabric was impregnated with this slurry. After smoothing both sides with a cutting blade, the fabric was placed in a coagulation bath (a mixture of DMF and water at 40°C) with a DMF concentration of 30% for coagulation. Subsequently, it was subjected to weight reduction extraction in toluene and dried at 150°C (5 min). Finally, it was brushed with 600-grit sandpaper at a brushing speed of 800 m / min and a cutting depth of 0.1 mm to create a microfiber velvet surface. Electrical resistance and flame retardancy tests were then performed, showing an electrical resistance level of 10. 5 On the order of Ω / m 2 (Ohms per square meter), flame retardant rating is A-0.

[0028] Example 7

[0029] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 2.0 mm was selected. An impregnation slurry with a viscosity of 2500 mPa / s was prepared using 12.5% ​​polyurethane resin (modulus 100) and 25% amorphous aluminum hydroxide (D50 350 nm) as solvent (DMF). The nonwoven fabric was then impregnated with this slurry. After smoothing both sides with a cutting blade, the fabric was placed in a coagulation bath (a mixture of DMF and water at 40°C) with a DMF concentration of 30% for coagulation. Subsequently, the fabric was subjected to weight reduction extraction in toluene and dried at 150°C for 5 min. Finally, it was brushed with 320-grit sandpaper at a brushing speed of 500 m / min and a cutting depth of 0.1 mm to create a microfiber velvet surface. The resistivity and flame retardancy were then tested, and the results showed a resistivity level of 10. 5 On the order of Ω / m 2 (Ohms per square meter), flame retardant rating is A-0.

[0030] Example 8

[0031] A piece of PA6 / PE island-type microfiber nonwoven fabric with a thickness of 2.0 mm was selected. An impregnation slurry with a viscosity of 3000 mPa / s was prepared using 20% ​​polyurethane resin (modulus 100) and amorphous aluminum hydroxide with a particle size D50 of 550 nm, with DMF as the solvent and amorphous aluminum hydroxide accounting for 22.5% of the mass. The nonwoven fabric was impregnated with this slurry. After smoothing both sides with a cutting blade, the fabric was placed in a coagulation bath with a DMF concentration of 20% (a mixture of DMF and water at 40°C) for coagulation. Subsequently, it was subjected to weight reduction extraction in toluene and dried at 180°C (5 min). Finally, it was brushed with 240-grit sandpaper at a brushing speed of 600 m / min and a cutting depth of 0.1 mm to create a microfiber velvet surface. Finally, its electrical resistance and flame retardancy were tested, and the results showed an electrical resistance level of 10. 5 On the order of Ω / m 2 (Ohms per square meter), flame retardant rating is A-0.

[0032] The above description is merely a preferred embodiment of the present invention. It should be noted that the scope of protection of the present invention is not limited thereto. Any person skilled in the art who, within the technical scope disclosed in the present invention, conceives of the invention and makes equivalent substitutions or modifications based on the technical solution of the present invention should be included within the scope of protection of the present invention.

[0033] The test standards for the above embodiments are explained as follows: In this invention, the resistance level test is performed according to "GB / T 1410-2006 Test Method for Volume Resistivity and Surface Resistivity of Solid Insulating Materials", and the flame retardancy test is performed according to "GB 8410-2006 Combustion Characteristics of Automotive Interior Materials".

Claims

1. A method for preparing a microfiber suede surface with conductive and flame-retardant properties, characterized in that, Includes the following steps: 1) Prepare island-type microfiber nonwoven fabric and slurry. Immerse the island-type microfiber nonwoven fabric in the slurry. After scraping the top and bottom surfaces with a liquid cutter, it is placed in a coagulation bath for coagulation. The fabric is then extracted by reducing the amount of material, dried, and brushed to obtain a microfiber velvet surface with conductive and flame-retardant properties. 2) The slurry is composed of polyurethane resin, nano-amorphous aluminum hydroxide or magnesium hydroxide, and solvent DMF.

2. The method for preparing a microfiber velvet surface with conductive and flame-retardant properties as described in claim 1, characterized in that, The sea phase of island-type microfiber nonwoven fabric is PE or COPET, and the island phase is PA or PET.

3. The method for preparing a microfiber velvet surface with conductive and flame-retardant properties as described in claim 1, characterized in that, The mass percentage of polyurethane resin in the slurry is 10%~25%, and the mass percentage of nano-amorphous aluminum hydroxide or magnesium hydroxide is 5%~40%. If it is less than 5%, the flame retardancy and conductivity will be insufficient. If it is more than 40%, the viscosity of the prepared slurry will be too high, which is not conducive to the subsequent impregnation process. The particle size D50 of nano-amorphous aluminum hydroxide or magnesium hydroxide is controlled in the range of 1~800nm, the modulus of polyurethane resin is 30~250, and the overall viscosity of the slurry is controlled between 1000~8000mPa / s.

4. The method for preparing a microfiber velvet surface with conductive and flame-retardant properties as described in claim 1, characterized in that, The coagulation bath is a mixed solution of DMF and water, with DMF accounting for 10% to 50% of the mass of the mixed solution, and the coagulation bath temperature is 30℃ to 60℃.

5. The method for preparing a microfiber suede surface with conductive and flame-retardant properties as described in claim 1, characterized in that, The reduction extraction is either toluene reduction extraction or alkali reduction extraction.

6. The method for preparing a microfiber velvet surface with conductive and flame-retardant properties as described in claim 1, characterized in that, The drying temperature is 90-180℃, and the drying time is 3-8 minutes.

7. The method for preparing a microfiber suede surface with conductive and flame-retardant properties as described in claim 1, characterized in that, The sandpaper used for sanding is 180-600 grit, the grinding depth is 0.05-0.1 mm, and the sandpaper linear speed is 400-1100 m / min.