Flexible capacitive sensor based on conductive rubber

Abstract

The invention provides a flexible capacitive sensor based on conductive rubber. According to the sensor, flexible conductive rubber is used as a conductive pole plate, flexible pure rubber is used asa dielectric layer, a spraying process is utilized to prepare all layers of the capacitive sensor, and a surface microstructure is used as assistance. The prepared flexible capacitive sensor makes a remarkable signal response to an external load and can be used for stretching, compression and movement tests, wherein the pure rubber of the dielectric layer is prepared by mixing 80-90wt% of liquid rubber and 10-20wt% of a curing agent; the conductive rubber is prepared by mixing 40wt%-60wt% of liquid rubber, 10-15wt% of a curing agent, 20wt%-30wt% of a conductive filler and 10-20wt% of a diluent; and through layered spraying and step-by-step or overall curing, the flexible capacitive sensor with a good mechanical signal response is obtained. According to the capacitor, the conductive pole plate layer is conductive rubber, the dielectric layer is pure liquid rubber, and therefore the capacitor is a complete flexible sensor in a true sense.

Description

technical field [0001] The invention relates to a flexible capacitive sensor based on conductive rubber, and the flexible capacitor prepared by it can be used as an electronic element and a sensor device, and belongs to the field of electronic equipment. Background technique [0002] Flexible electronic devices have broad prospects in the current development, such as flexible smartphones, electronic skin, wearable health detectors and other fields. At present, flexible electronic devices are mostly used in the field of sensors. Connect the sensor to the matching circuit and signal processor, and under the external load and specific environment, the electrical performance of the flexible sensor will change, so as to achieve the effect of signal feedback. Flexible sensors have great development potential in the fields of wearable electronic materials and future human-computer interaction, mainly capacitive and resistive sensors. Flexible capacitive sensors often use pure rub...

AI Technical Summary

Problems solved by technology

The limitations of this patent: 1) The electrode pattern prepared by the photolithography process is complicated, and the cleaning of the photoresist leads to large emissions and high cost

2) The metal electrode is an inflexible material. Although it is attached to the flexible rubber, its overall structure is an incompletely flexible material.

3) The lack of test data of sensor performance in the patent statement makes it difficult to evaluate its performance

The limitations of this patent: 1) The metal electrode is prepared by photolithography process, which is cumbersome and polluting; 2) The metal electrode is a non-flexible material. Although it is attached to the LCP flexible substrate, the overall structure is still an incompletely flexible material. , and the affinity between the metal film and the LCP substrate is average, and the wearability is poor; 3) The graphene oxide contained in the dielectric layer used has low output and high price

The limitations of this patent: 1) The conductive metal film is pasted on the elastic insulating film as the electrode layer, which is not a fully flexible material, and the specific material used is not reported in the patent; 2) The interdigitated array structure is passed through photolithography Prepared by the method, the process steps are complicated, and there will be emissions in the glue removal process; 3) The performance index of the sensor for the pulse test is missing in the patent

[0015] (1) The electrode layer material of the capacitive sensor may use conductive fillers (particles, fibers or nanowires), and use a solvent as a carrier to smear on the flexible lining to form a two-layer spliced ​​structure, or to form a two-layer composite structure on the flexible lining by evaporation. The metal film (copper, aluminum, gold or silver) is deposited on the board. The electrode layer of this conductive layer and the flexible backing structure is not a completely flexible structure in the true sense. The electrode is easily damaged when loaded, and when loaded many times The interface is easy to crack

[0016] (2) Most capacitive sensors invented by patents are commonly used to construct electrode lines or surface microstructures by photolithography. The process is cumbersome, the emission is large, and the cost is high.

[0017] (3) Most studies design internal or surface microstructures to improve sensor sensitivity, but the preparation of microstructures is mainly based on photolithography and injection molding, which is cumbersome and costly

[0018] (4) Some electrode materials use precious metals or nano-metal wires, which are costly;

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