CN107411735A - A kind of bioelectrical signals flexibility dry-type electrode and preparation method thereof - Google Patents

Abstract

The invention relates to a flexible dry electrode for bioelectrical signals and a preparation method thereof. This electrode is suitable for EEG (forehead area), muscle electrical signal, ECG and other signal transduction in hairless or less hairy areas. The dry electrode consists of two parts: a conductive flexible dry electrode body and an electrical connector. The body of the conductive flexible dry electrode is made of flexible composite conductive material, which has both flexibility and good conductivity; the surface is a three-dimensional curved surface, which can fully contact the skin and can suppress motion artifacts. The electrical connector is integrally cast in the electrode using an integral molding process, which reduces the complexity of the process and reduces the contact resistance of the electrical connector-electrode body. The invention has the advantages of no need for conductive glue/paste, simple and convenient operation, low impedance, long-term stability and reliability, flexibility, comfortable and safe wearing, low cost and simple processing technology.

Description

A flexible dry electrode for bioelectrical signals and its preparation method

technical field

The invention relates to electrodes in the field of medical equipment and wearable electronics, in particular to a flexible dry electrode for measuring bioelectrical signals in hairless or less-haired areas and a preparation method thereof.

Background technique

With the development of economy and society, people pay more and more attention to life and health, and the development of medical and health field is unprecedentedly prosperous. Physiological electrical signals for evaluating health status play an important role in medical diagnosis and are an indispensable key means. Bioelectrical signals include electrocardiograms (ECG), electroencephalograms (EEG), electrooculograms (EOG) and electromyograms (EMG). These signal forms contain a large amount of physiological information. With the help of modern biological Instrument technology, providing non-invasive, low-cost clinical physiological monitoring and drug treatment for the growing global medical needs.

Medical electrodes can extract these electrical signals for people to analyze, and are indispensable and important sensing devices in medical instruments. In the existing bioelectrical signal collection methods, silver/silver chloride wet electrodes are usually used to collect signals. Although the contact impedance between this wet electrode and the skin is small, bioelectrical signals with high signal-to-noise ratio can be collected, but it There are still many shortcomings. Take the EEG electrode as an example: first, the electrode position needs to be wiped with an abrasive paste that removes the cuticle to reduce skin impedance, and a conductive paste is applied. The conductive paste takes time to diffuse into the cuticle, so the whole preparation process is time-consuming and laborious; Secondly, the use of conductive paste will stain the tester's skin and cause great discomfort. In severe cases, it may even cause side effects such as allergies or skin ulcers; finally, as time goes by, the conductive paste will evaporate and dry out, resulting in poor electrode performance. deterioration, it is not suitable for long-term monitoring.

Dry electrodes do not need to use conductive paste during use, and become an ideal substitute for traditional wet electrodes due to their convenience, quickness and long-term stability. In recent years, dry electrode technology has received extensive attention from researchers, and dry electrodes based on different electrode materials and structures have been proposed accordingly. However, these dry electrodes have disadvantages during use, such as high contact resistance, sensitivity to motion artifacts, and electrodes that are too hard for comfort.

Contents of the invention

In view of the deficiencies in the above-mentioned prior art, the purpose of the present invention is to provide a flexible dry electrode for collecting bioelectrical signals in hairless or hairless areas and its preparation method, so as to solve the problem of existing dry electrodes. High impedance, poor comfort and other issues.

The technical scheme that the present invention solves the above problems is as follows:

A flexible dry electrode for bioelectrical signal acquisition, comprising: a flexible dry electrode body and an electrical connector, wherein the flexible dry electrode body is made of a flexible conductive composite material, and its surface is a three-dimensional curved surface, which is easy to contact with the skin surface In close contact, the part of the electrical connector protruding from the flexible dry electrode body is used to connect the back-end measurement circuit wires, and the electrical connector is integrated with the electrode body by integral molding process.

In a further implementation, the material of the conductive flexible dry electrode body is conductive rubber or conductive silica gel, that is, the base material is rubber or silica gel, and the filler is carbon-based conductive filler (such as carbon black, carbon nanotubes, graphene, etc.) or At least one of metal-based conductive fillers (such as silver powder, aluminum silver plating, nickel powder, etc.).

In a further implementation, the surface of the conductive flexible dry-type electrode that contacts the skin is an arc-shaped three-dimensional curved surface, which is easy to closely fit and contact with the skin. The two-dimensional shape of its body is rectangle, circle or others.

Further implemented, the electrical connector part is: a metal conductive snap button, a metal conductive connecting piece or other metal connecting parts, and the metal material thereof is gold, silver, copper, platinum, etc. The part where the electrical connector is in contact with the electrode body can open holes or adopt other structures such as probes to increase the contact area.

The invention provides a method for preparing a flexible dry electrode, comprising the following steps:

1) Make the mold of the flexible dry electrode by machining method;

2) Place the electrical connector in the mold and leave the joint position, and then pour the conductive material, so that the electrical connector and the body can be integrally formed.

In the above preparation method, the bottom of the mold is an arc-shaped three-dimensional curved surface, and the two-dimensional shape of the mold in a top view is rectangle, circle or others.

In the above preparation method, the conductive material is conductive rubber or conductive silica gel, that is, the base material is rubber or silica gel, and the filler is carbon-based conductive filler (such as carbon black, carbon nanotube, graphene, etc.) or metal-based conductive filler (such as silver powder, Aluminum silver plating, nickel powder, etc.) at least one.

In the above preparation method, the electrical connector part is: a metal conductive snap button, a metal conductive connecting piece or other metal connecting parts, and the metal material thereof is gold, silver, copper, platinum, etc. The part where the electrical connector is in contact with the electrode body can open holes or adopt other structures such as probes to increase the contact area.

Compared with the prior art, the present invention has the following beneficial effects:

The body of the flexible dry electrode of the present invention is made of a flexible conductive composite material, and the surface is a three-dimensional curved surface, which can better fit the skin, increase the contact area between the electrode and the skin, and at the same time suppress motion artifacts and increase the quality of the collected signal and stability; the electrode body is made of flexible composite conductive material, which has both flexibility and good conductivity; the electrical connector is integrally cast in the electrode, which reduces the complexity of the process, and reduces the contact resistance of the electrical connector-electrode body, and is convenient Connect the measurement circuit.

Description of drawings

Figure 1a is a schematic diagram of the overall structure when the contact surface of the flexible dry electrode of the embodiment is facing upward;

Fig. 1b is a schematic structural view of one side of the electrical connector of the flexible dry electrode shown in Fig. 1a.

Figure 2a is a schematic diagram of the overall structure of another embodiment of the flexible dry electrode with the contact surface facing upwards;

Fig. 2b is a schematic diagram of the structure of the other side of the flexible dry electrode shown in Fig. 2a.

Fig. 3 is a flowchart of an electrode preparation method according to an embodiment of the present invention.

detailed description

The present invention will be described in detail below in conjunction with specific embodiments. It should be understood that these implementations are described only to enable those skilled in the art to better understand and implement the present disclosure, but not to limit the scope of the present disclosure in any way. It should be noted that, if there are any processes or parameters that are not specifically described in detail below, those skilled in the art can understand or implement them with reference to the prior art.

As shown in Figure 1, this example provides a flexible dry electrode for collecting bioelectrical signals in areas without hair or less hair, including: a conductive flexible dry electrode body 1 and an electrical connector 2, wherein the conductive flexible electrode The dry electrode body 1 is used for contact with the skin and is made of flexible conductive composite material. Its surface is designed as a three-dimensional curved surface. The electrical connector 2 is used to connect with the measurement circuit. Body 1 connection.

The material of the conductive flexible dry electrode body 1 is conductive rubber or conductive silica gel, that is, the base material is rubber or silica gel, and the filler is carbon-based conductive filler (such as carbon black, carbon nanotube, graphene, etc.) or metal-based conductive filler. At least one of conductive fillers (such as silver powder, aluminum silver-plated, nickel powder, etc.), the mass ratio of the specific doped substance is determined according to the specific doped substance and the specific dispersion method.

The surface of the conductive flexible dry-type electrode body 1 that contacts the skin is an arc-shaped three-dimensional curved surface, which is easy to closely fit and contact with the skin. The two-dimensional shape of its body is rectangular, circular or other, as shown in Figure 1a, Figure 1b, Figure 2a, and Figure 2b.

The electrical connector 2 is: a metal conductive snap button, a metal conductive connecting piece or other metal connecting parts, and its metal material is gold, silver, copper, platinum, etc. The part where the electrical connector is in contact with the electrode body can open holes or adopt other structures such as probes to increase the contact area.

As an example only, as shown in Figure 3, it is a flow chart of an embodiment of a flexible dry electrode preparation method provided by the present invention, including the following steps:

1) Make the mold of the flexible dry electrode by machining method;

2) Place the electrical connector in the mold and leave the joint position, and then pour the conductive material, so that the electrical connector and the body can be integrally formed.

The advantage of the novel flexible dry-type electrode designed by the present invention is that the electrode is composed of two parts: a conductive flexible dry-type electrode body and an electrical connector. Among them, the conductive flexible dry electrode body is made of flexible composite conductive material, which has both flexibility and good conductivity; the surface is designed with a three-dimensional curved surface, which can fully contact the skin and can suppress motion artifacts. The electrical connector is integrally cast in the electrode by an integral molding process, which reduces the complexity of the process, reduces the electrical connector-electrode body contact impedance, and facilitates the connection of the measurement circuit.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and those skilled in the art can think of various variations or modifications, but without departing from the spirit of the present disclosure, all modifications and replacements made will fall within It is within the scope of the present disclosure as defined by the appended claims.

Claims (6)

1. a kind of bioelectrical signals flexibility dry-type electrode, for the acquiring biological electric signals without hair or few hair area, it is special Sign is, including flexible dry type electrode body and electrical interconnecting means, wherein flexible dry type electrode body uses compliant conductive composite wood Material, flexible dry type electrode body contact surface for can with skin surface be in close contact three dimension arch curved surface, electrical interconnecting means with Integrally connection is realized in cast to flexible dry type electrode body, and the part of the flexible dry type electrode body of electrical interconnecting means stretching is used for and rear end Measuring circuit is connected by electric wire.

A kind of 2. bioelectrical signals flexibility dry-type electrode according to claim 1, it is characterised in that the flexible dry type electricity For the base material for the flexible conductive composite material that pole body uses for conductive rubber or electric silica gel, filler is carbon conductive filler or gold One or more in category system conductive filler.

3. a kind of bioelectrical signals flexibility dry-type electrode according to claim 1, it is characterised in that the carbon series conductive is filled out Material includes carbon black, CNT or graphene；The me tallic conductive filler includes that silver powder, aluminium is silver-plated or nickel powder.

A kind of 4. bioelectrical signals flexibility dry-type electrode according to claim 1, it is characterised in that flexible dry-type electrode sheet The contact surface of body is that to contact the surface of skin be arc three-dimension curved surface, the two-dimensional shapes of flexible dry type electrode body be rectangle, Circular or other shapes.

5. a kind of bioelectrical signals flexibility dry-type electrode according to claim 1, it is characterised in that electrical interconnecting means are used and led Electric metal snap-fastener, metallic conduction connection sheet, its metal material are gold, silver, copper or platinum；Electrical interconnecting means and flexible dry type electrode body The part of contact uses perforate or multiprobe structure.

6. prepare a kind of any one of claim 1 ~ 5 method of bioelectrical signals flexibility dry-type electrode, it is characterised in that profit The method being machined into makes the mould of flexible dry-type electrode；Electrical interconnecting means are placed in a mold and reserve joint location, The cast of conductive material is carried out again, makes electrical interconnecting means and this body by integral forming.