CN-122028301-A - Flexible circuit composite film and preparation method and application thereof

CN122028301ACN 122028301 ACN122028301 ACN 122028301ACN-122028301-A

Abstract

The invention provides a flexible circuit composite film, a preparation method and application thereof, and belongs to the technical field of flexible circuit substrates. The flexible circuit composite film comprises a flexible fabric layer, an adhesive layer and a laser-induced graphene composite film which are sequentially arranged from top to bottom, wherein the laser-induced graphene composite film comprises a graphene circuit layer and a polyimide fiber film, and the graphene circuit layer is in contact with the adhesive layer. According to the invention, the graphene circuit layer is packaged between the flexible fabric and the polyimide film through the sandwich structure, so that performance attenuation of the graphene circuit caused by external mechanical friction, oxidation or a wet environment is effectively avoided, and durability and reliability of the circuit are remarkably improved.

Inventors

ZHANG XUEPING
Fang Bingying
WANG RONGWU
XU JINGJING
WANG ZEBO

Assignees

东华大学

Dates

Publication Date: 20260512
Application Date: 20260309

Claims (10)

1. The flexible circuit composite film is characterized by comprising a flexible fabric layer, an adhesive layer and a laser-induced graphene composite film which are sequentially arranged from top to bottom, wherein the laser-induced graphene composite film comprises a graphene circuit layer and a polyimide fiber film, and the graphene circuit layer is in contact with the adhesive layer.
2. The flexible circuit composite film of claim 1 wherein the flexible fabric comprises one or more of a polyimide fiber fabric, an aramid fiber fabric, a pre-oxidized fiber fabric, a cellulose fiber fabric, or a glass fiber fabric.
3. The flexible circuit composite film of claim 1 wherein the adhesive layer comprises one or more of polyurethane, polyamide, polyethylene, polypropylene, and polyester.
4. The flexible circuit composite film according to claim 1, wherein the method for preparing the polyimide fiber film comprises the steps of: preparing polyamide acid spinning solution; carrying out electrostatic spinning on the polyamic acid spinning solution to obtain a polyamic acid fiber membrane; and imidizing the polyamide acid fiber membrane to obtain the polyimide fiber membrane.
5. The flexible circuit composite film according to claim 4, wherein the polyamic acid spinning solution comprises polyamic acid and a polar solvent, wherein the polar solvent comprises one or more of N-methylpyrrolidone, N-dimethylformamide and N, N-dimethylacetamide; the mass fraction of the polyamic acid spinning solution is 8-20%.
6. The flexible circuit composite film according to claim 4 or 5, wherein the electrostatic spinning process parameters comprise 8-20 kV voltage, 10-25 cm receiving distance, 0.2-2 mL/h spinning solution supply rate and 10-60% environmental humidity.
7. The flexible circuit composite film of claim 4 wherein the imidization treatment comprises a first stage and a second stage that are performed sequentially; The temperature of the first stage is 200-250 ℃, the heat preservation time is 0.5-1 h, the temperature of the second stage is 350-400 ℃, and the heat preservation time is 1-2 h.
8. The method for preparing the flexible circuit composite film according to any one of claims 1 to 7, comprising the steps of: constructing a graphene circuit layer on the surface of the polyimide fiber film by adopting a laser-induced graphene technology to obtain a laser-induced graphene composite film; And bonding one side of the laser-induced graphene composite film, which is provided with the graphene circuit layer, with the flexible fabric layer by adopting an adhesive layer to obtain the flexible circuit composite film.
9. The preparation method of the graphene according to claim 8, wherein the technological parameters of the graphene include 5-20W of laser power, 10-500 mm/s of scanning speed and 0.01-0.1 mm of scanning line spacing; the bonding is hot-pressing compounding, the temperature of the hot-pressing compounding is 100-200 ℃, the pressure is 1.0-3.0 MPa, and the heat preservation and pressure maintaining time is 60-120 s.
10. The use of the flexible circuit composite film according to any one of claims 1 to 7 or the flexible circuit composite film prepared by the preparation method according to claim 8 or 9 in wearable equipment, flexible display, soft robots or electric heating.

Description

Flexible circuit composite film and preparation method and application thereof Technical Field The invention belongs to the technical field of flexible circuit substrates, and particularly relates to a flexible circuit composite film, a preparation method and application thereof. Background With the rapid development of wearable devices, flexible displays, and soft robots, there is an increasing demand for flexible circuit substrates. An ideal flexible circuit substrate should have excellent flexibility, bendability, heat resistance, and stable electrical properties. The traditional printed circuit board has high rigidity and brittleness, and is difficult to meet the requirements. Meanwhile, in the fields of intelligent wearing, automobile seat heating, medical physiotherapy and the like, great demands are also made on flexible, safe and efficient electric heating elements. Polyimide is widely used as a substrate for flexible circuits due to its excellent high temperature resistance, mechanical strength and chemical stability. And the Laser Induced Graphene (LIG) technology is a technology for directly generating porous graphene on the surface of a polymer through laser etching, can perform patterning and customizing, and has the advantages of quick processing, no need of masks, no need of chemical reagents and the like. However, commercial PI films have limited flexibility and breathability and are prone to fatigue cracking under multiple dynamic bending. And LIG circuits generated directly on the surface of a single PI film in the prior art are exposed to the outside and are easily affected by mechanical scraping, oxidation or humid environment, so that the circuit performance is attenuated or even fails. In addition, although LIG has excellent electrothermal conversion performance for electric heating, the bare heating circuit has the problems of safety risk and short service life. Therefore, there is an urgent need to develop a flexible composite film that can effectively protect a circuit and has excellent overall flexibility, and expand its dual applications in the fields of flexible circuits and electric heating. Disclosure of Invention The invention aims to provide a flexible circuit composite film, a preparation method and application thereof, the graphene circuit layer is packaged between a flexible fabric and a PI film through a sandwich structure, effectively protects the circuit, obviously improves the durability and the reliability of the circuit, the structure enables the composite film to be used as a flexible circuit board with high reliability and a flexible electric heating element. In order to achieve the purpose of the invention, the invention provides the following technical scheme: the flexible circuit composite film comprises a flexible fabric layer, an adhesive layer and a laser-induced graphene composite film which are sequentially arranged from top to bottom, wherein the laser-induced graphene composite film comprises a graphene circuit layer and a polyimide fiber film, and the graphene circuit layer is in contact with the adhesive layer. Preferably, the flexible fabric comprises one or more of a polyimide fiber fabric, an aramid fiber fabric, a pre-oxidized fiber fabric, a cellulose fiber fabric, or a glass fiber fabric. Preferably, the adhesive layer comprises one or more of polyurethane, polyamide, polyethylene, polypropylene and polyester. Preferably, the preparation method of the polyimide fiber membrane comprises the following steps: preparing polyamide acid spinning solution; carrying out electrostatic spinning on the polyamic acid spinning solution to obtain a polyamic acid fiber membrane; and imidizing the polyamide acid fiber membrane to obtain the polyimide fiber membrane. Preferably, the polyamic acid spinning solution comprises polyamic acid and a polar solvent, wherein the polar solvent comprises one or more of N-methylpyrrolidone, N-dimethylformamide and N, N-dimethylacetamide; the mass fraction of the polyamic acid spinning solution is 8-20%. Preferably, the electrostatic spinning process parameters comprise 8-20 kV voltage, 10-25 cm receiving distance, 0.2-2 mL/h spinning solution supply rate and 10-60% environmental humidity. Preferably, the imidization treatment includes a first stage and a second stage which are sequentially performed; The temperature of the first stage is 200-250 ℃, the heat preservation time is 0.5-1 h, the temperature of the second stage is 350-400 ℃, and the heat preservation time is 1-2 h. The invention also provides a preparation method of the flexible circuit composite film, which comprises the following steps: constructing a graphene circuit layer on the surface of the polyimide fiber film by adopting a laser-induced graphene technology to obtain a laser-induced graphene composite film; And bonding one side of the laser-induced graphene composite film, which is provided with the graphene circuit layer, with the flexible fabric layer by