CN112998713B - Method for manufacturing flexible electrode based on fabric - Google Patents
Method for manufacturing flexible electrode based on fabric Download PDFInfo
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- CN112998713B CN112998713B CN202110162893.XA CN202110162893A CN112998713B CN 112998713 B CN112998713 B CN 112998713B CN 202110162893 A CN202110162893 A CN 202110162893A CN 112998713 B CN112998713 B CN 112998713B
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Abstract
The invention discloses a method for manufacturing a flexible electrode based on fabric, which comprises the following steps of preparing an electrode layer on an electrode adhesion layer with the thickness of 0.025mm-0.15 mm; the electrode attachment layer is attached to the flexible fabric in a hot-pressing mode to form the flexible electrode, and the method for manufacturing the flexible electrode based on the fabric has the advantages of being good in electric conductivity, strong in comfort and high in timeliness, and can meet the wearing requirements of users; the electrode layer is prepared on the electrode attachment layer with the thickness of 0.025mm-0.15mm, the electrical property is stable, the surface is smooth, the electrode layer can be uniformly attached to the skin, the flexible electrode formed by matching flexible fabrics has good flexibility and skin-friendly property, can be closely attached to the skin in the using process, is moderate in elasticity, meets the requirement of comfort level during wearing on the premise of ensuring stable electrical property, and meets the requirement of repeated use for many times.
Description
Technical Field
The invention relates to the technical field of electrode preparation, in particular to a method for manufacturing a flexible electrode based on fabric.
Background
At present, the most commonly used bioelectrical signal collecting electrodes are mainly classified into wet electrodes and dry electrodes; one of the wet electrodes mainly takes silver chloride electrode (Ag/AgCl) silver paste as a main material, the silver paste needs to be cleaned before and after use, which wastes time and labor, and the other wet electrode is conductive suspected glue, but the electrode can be used only once, the use duration is limited, and after long-time use, the conductive gel can become dry, so that the contact property and the conductive property with skin are reduced; the dry electrode mainly comprises a conductive metal hard dry electrode and a conductive fabric dry electrode, wherein the conductive metal hard dry electrode is of a hard structure in form and is easy to cause uncomfortable feeling during wearing; the contact surface of the conductive fabric dry electrode and the skin is relatively incomplete, and the conductive fabric dry electrode is easy to deform after being stretched to cause impedance change, so that the quality of acquired signals is poor; therefore, how to make the electrode have good conductive performance, and have the characteristics of good comfort and long-term multi-frequency use is a technical problem to be solved in the field.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the method for manufacturing the flexible electrode based on the fabric is provided, and aims to solve the technical problems of poor conductivity, poor comfort and low timeliness of the electrode in the prior art.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a method for manufacturing a flexible electrode based on fabric comprises the following steps,
preparing an electrode layer on the electrode adhesion layer with the thickness of 0.025mm-0.15 mm;
and attaching the electrode adhesion layer to the flexible fabric in a hot pressing mode to form the flexible electrode.
The invention has the beneficial effects that: the flexible electrode prepared by the method for manufacturing the flexible electrode based on the fabric has the characteristics of good conductivity, strong comfort and high timeliness, and can meet the wearing requirements of users; the electrode layer is prepared on the electrode attachment layer with the thickness of 0.025mm-0.15mm, the electrical property is stable, the surface is smooth, the electrode layer can be uniformly attached to the skin, the flexible electrode formed by matching flexible fabrics has good flexibility and skin-friendly property, the electrode layer can be closely attached to the skin in the use process, the elasticity is moderate, the requirement of comfort level during wearing is met on the premise that the electrical property is stable, and the requirement of long-time multi-frequency use is met.
Drawings
Fig. 1 is a flow chart of a method for manufacturing a flexible electrode based on a fabric according to a first embodiment of the present invention;
fig. 2 is a schematic structural diagram of a flexible electrode manufactured by using a method for manufacturing a flexible electrode based on a fabric according to a first embodiment of the present invention;
fig. 3 is a schematic cross-sectional structure diagram of a flexible electrode prepared by using the method for manufacturing a flexible electrode based on a fabric according to the first embodiment of the present invention in an unfolded state;
fig. 4 is a schematic cross-sectional structure diagram of a flexible electrode manufactured by using the method for manufacturing a flexible electrode based on a fabric according to the first embodiment of the present invention in a wearing state;
fig. 5 is a display diagram of a cardiac signal acquisition by a flexible electrode prepared by a method for manufacturing a flexible electrode based on a fabric according to a first embodiment of the present invention;
fig. 6 is a display diagram of electroencephalogram signal acquisition of a flexible electrode prepared by the method for manufacturing the flexible electrode based on the fabric according to the first embodiment of the present invention.
Description of reference numerals:
1. a flexible fabric; 2. an adhesive layer; 21. hot melt adhesive film; 22. a hot melt adhesive film; 3. an electrode attachment layer; 4. and an electrode layer.
Detailed Description
In order to explain technical contents, achieved objects, and effects of the present invention in detail, the following description is made with reference to the accompanying drawings in combination with the embodiments.
Referring to fig. 1 to 3, a method for manufacturing a flexible electrode based on a fabric includes the steps of preparing an electrode layer 4 on an electrode attachment layer 3 having a thickness of 0.025mm to 0.15 mm;
and attaching the electrode attachment layer 3 to the flexible fabric 1 in a hot-pressing manner to form the flexible electrode.
From the above description, the beneficial effects of the present invention are: the electrode layer 4 is prepared on the electrode attachment layer 3 with the thickness of 0.025mm-0.15mm, the electrode layer is stable in electrical property and smooth in surface, and can be uniformly attached to the skin, the flexible electrode formed by the flexible fabric 1 has good flexibility and skin affinity, can be closely attached to the skin in the using process, is moderate in elasticity, and meets the requirement of comfort level during wearing on the premise of ensuring stable electrical property.
Further, the elongation of the electrode attachment layer 3 is less than 5%.
From the above description, it can be seen that the elongation of the electrode attachment layer 3 is less than 5%, the dimensional stability is good, the electrode layer 4 made based thereon does not cause significant changes in electrode impedance due to excessive stretching, and the comfort of contacting the flexible electrode with the skin can be improved.
Further, an adhesive layer 2 is further arranged between the electrode adhesion layer 3 and the flexible fabric 1, and the electrode adhesion layer 3 is attached to the flexible fabric 1 through the adhesive layer 2.
As can be seen from the above description, the adhesive layer 2 facilitates the electrode attachment layer 3 to be closely attached to the flexible fabric 1.
Further, the adhesive layer 2 is a hot melt adhesive or a hot melt adhesive film 21.
As can be seen from the above description, the bonding form of the bonding layer 2 can be selected according to the actual application requirements.
Further, when the electrode adhesion layer 3 is attached to the flexible fabric 1 by hot pressing, the electrode adhesion layer 3 is maintained at a temperature of 130 to 150 ℃ for 3 to 10 seconds.
As can be seen from the above description, the pressure of the electrode adhesion layer 3 is maintained at 130 ℃ to 150 ℃ for 3 to 10 seconds, so that the adhesive layer 2 has a better adhesive effect and a better bonding effect.
Further, the material of the electrode adhesion layer 3 is PI or PET.
As can be seen from the above description, the material of the electrode adhesion layer 3 can be selected according to the actual application requirements, which is favorable for the expansion of the design dimension.
Further, the electrode layer 4 is printed and formed on the electrode adhesion layer 3 through a printing process.
As can be seen from the above description, the electrode layer 4 is directly printed and formed on the electrode adhesion layer 3 by a printing process, which is simple in process and beneficial to improving the production efficiency.
Further, after the electrode layer 4 is formed, the electrode layer 4 is baked at 150 ℃ for 10 minutes, or at 130 ℃ for 30 minutes.
According to the above description, after the electrode layer 4 is formed, the electrode layer 4 is baked at a high temperature, so that the adhesive force of the silver paste on the electrode adhesive layer 3 can be increased, and the risk of edge warpage of the electrode layer 4 is reduced.
Example one
Referring to fig. 1 and fig. 2, a first embodiment of the present invention is: a method for manufacturing a flexible electrode based on fabric comprises the following steps,
s1, providing a flexible fabric 1 as a substrate, specifically, the flexible fabric 1 is made of polyester, and in addition, the flexible fabric 1 can also be but not limited to superfine fibers, rayon, mixed fabrics of fibers and cotton, wool, silk and hemp and the like or mixed fabrics of polyester, polyurethane and rayon.
S2, providing an electrode adhesion layer 3, wherein the elongation of the electrode adhesion layer 3 is less than 5%, preparing an electrode layer 4 on the electrode adhesion layer 3, optionally, the material of the electrode adhesion layer 3 may be PI (polyimide) or PET (poly terephthalic acid plastic), and may be specifically selected according to the actual application requirements, in this embodiment, the material of the electrode adhesion layer 3 is a PET material, and due to the characteristics of the PET material, the electrode adhesion layer 3 has the characteristics of smooth surface, creep resistance, friction resistance, strong dimensional stability, and the like; furthermore, after multiple verification, the thickness of the electrode attachment layer 3 is preferably selected from 0.025mm to 0.15 mm; the electrode adhesion layer 3 is too thick, so that the hardness of the flexible electrode is increased, and the flexibility of the flexible electrode is influenced; since the processing difficulty is increased when the electrode adhesion layer 3 is too thin, PET having a thickness of 0.05mm is used as the electrode adhesion layer 3 in this embodiment.
In this embodiment, the electrode layer 4 is formed by: the electrode adhesion layer 3 is directly printed and formed through a printing process, specifically, the electrode layer 4 is made of a silver chloride electrode (Ag/AgCl), and in addition, the electrode layer 4 can also be made of stainless steel or conductive graphene, and the material for printing the electrode layer 4 can be specifically selected according to actual application requirements; further, for promoting electrode layer 4 (Ag/AgCl silver thick liquid) is in adhesive force on the electrode adhesion layer 3 (PET), reduces the risk of electrode layer 4 edge warpage, works as electrode layer 4 prints and carries out the high temperature to it after finishing and toasts, and is concrete, toasts 10 minutes under 150 ℃'s temperature condition, perhaps toasts 30 minutes under 130 ℃'s temperature condition.
Specifically, in the printing process, stretchable conductive silver paste is selected as a printing material of the electrode layer 4, the printing thickness is 0.03mm, the flexible electrode does not crack in a 5% stretching range, the impedance does not change obviously, the test resistivity is less than 1 ohm cm, and the actual measurement of the resistance between the surface of the electrode layer 4 and an electrode signal output contact point is less than 10 ohm.
Specifically, after the electrode layer 4 is printed and baked for 10 minutes at 150 degrees, the adhesive force of the electrode layer 4 on the electrode adhesion layer 3 can be increased, and after the electrode layer 4 is baked at high temperature and the adhesive force is tested for 100 times by using a 3M600 film transparent test tape, the surface of the electrode layer 4 has no obvious scratches or shedding phenomenon.
In other embodiments, the electrode layer 4 may be formed by: firstly, a copper film is pressed on the electrode adhesion layer 3, then the electrode layer 4 is formed on the electrode adhesion layer 3 through a photoetching process (comprising the procedures of exposure, development, etching and the like), further, when the electrode layer 4 is prepared through the photoetching process, the thickness of the electrode adhesion layer 3 is 0.075mm, and after the etching procedure, a pure gold layer with the thickness of 0.1 mu m is plated on the copper film, so that the problems that the copper film is easy to oxidize and the skin is easy to be allergic can be solved.
S21, attaching an insulating protection film to a partial area of the electrode layer 4, specifically, the electrode layer 4 comprises a contact part directly contacting with human skin and a conducting circuit not contacting with a human body, in order to avoid short circuit caused by exposure of the conducting circuit, the conducting circuit needs to be attached with the insulating protection film, and the thickness of the insulating protection film is 50 microns.
And S22, stamping the electrode adhesion layer 3, wherein the part, not printed with the electrode layer 4, of the electrode adhesion layer 3 is removed in a stamping mode, so that the volume of the electrode adhesion layer 3 can be reduced, and the overall flexibility and bendability of the electrode adhesion layer 3 and the flexible fabric 1 after being pressed are ensured.
S3, forming an adhesive layer 2 on one side, far away from the electrode layer 4, of the electrode attachment layer 3, wherein optionally, the adhesive layer 2 can be a hot melt adhesive coated on the electrode attachment layer 3, or the adhesive layer 2 can be a hot melt adhesive film 21, a hot melt adhesive net film 22 or a hot melt composite PET film which is adhered on the electrode attachment layer 3 in an adhering mode, or a hot melt adhesive rod can be dissolved at a high temperature and then uniformly coated on the electrode attachment layer 3 to form the adhesive layer 2; the bonding layer 2 is formed in a manner that the electrode adhesion layer 3 is tightly attached to the flexible fabric 1; further, the thickness of the adhesive layer 2 can be set according to actual application requirements, the wearing comfort of the flexible electrode is affected if the adhesive layer 2 is too thick, the stability of the impedance value is affected by the stretching interference of the flexible fabric 1 on the electrode attachment layer 3 if the adhesive layer 2 is too thin, and the reliability of the adhesion between the electrode attachment layer 3 and the flexible fabric 1 is affected if the adhesive layer 2 is too thin, so that the thickness range of the adhesive layer 2 is selected to be 0.1-0.8mm.
Referring to fig. 3 and 4, in this embodiment, the adhesive layer 2 includes at least one layer of hot melt adhesive film 21 and at least one layer of hot melt adhesive mesh film 22, specifically, the number of the hot melt adhesive films 21 is three, the number of the hot melt adhesive mesh films 22 is two, and one layer of the hot melt adhesive mesh film 22 is disposed between two adjacent layers of the hot melt adhesive films 21, it is easy to understand that when the flexible electrode is worn on a human body, the flexible fabric 1 is deformed and stretched in a certain radian, because the electrode attachment layer 3 is closer to the skin of the human body than the flexible fabric 1, the bending radian of the electrode attachment layer 3 is smaller than the bending radian of the flexible fabric 1 (as shown in fig. 4), when the electrode attachment layer 3 is deformed and stretched along with the deformation and stretching of the flexible fabric 1, the electrode attachment layer 3 is certainly affected to a certain degree of stretching, which is a main cause impedance change of the electrode attachment layer 3, but in this embodiment, the electrode attachment layer 3 and the flexible fabric 1 are bonded by the adhesive mesh film 22, because there are a plurality of through holes on the adhesive mesh film 22, impedance change of the electrode attachment layer 3 can be alleviated, and thus the electrode attachment layer 3 can be affected by the electrode attachment layer 3, and thus, the risk of the electrode attachment layer 3 can be reduced; more specifically, in two-layer above-mentioned in the hot melt adhesive nethike embrane 22, be close to electrode adhesion layer 3 one side the mesh number of hot melt adhesive nethike embrane 22 is greater than and is close to flexible fabric 1 one side the mesh number of hot melt adhesive nethike embrane 22, so, make the most action of tensile force of flexible fabric 1 is in the mesh number less on the hot melt adhesive nethike embrane 22, the tensile force of subtotal is through another hot melt adhesive nethike embrane 22 relieves to the mesh number is great hot melt adhesive nethike embrane 22 can ensure the stability that electrode adhesion layer 3 bonds.
S4, attaching the electrode attachment layer 3 coated with the bonding layer 2 to the flexible fabric 1;
specifically, firstly, the flexible fabric 1 is flattened, impurities and static electricity on the flexible fabric 1 are removed, and then the electrode adhesion layer 3 is attached to the flexible fabric 1 in a hot pressing mode, more specifically, in order to ensure the bonding effect of the bonding layer 2, the hot pressing temperature is 130-150 ℃, and the pressure maintaining time is 3-10 seconds, so that the hot melt adhesive of the bonding layer 2 can be fully dissolved and permeated between the adhesion layer 3 and the flexible fabric 1, and the attaching effect is better.
Further, after the electrode attachment layer 3 coated with the adhesive layer 2 is attached to the flexible fabric 1, a peeling test is performed on the electrode attachment layer 3, wherein the peeling force during the test is greater than 10N.
And S5, cutting the flexible fabric 1 attached with the electrode attachment layer 3 into a required shape.
S6, sewing the cut flexible fabric 1 to form a flexible electrode, and optionally filling soft and comfortable space cotton and other materials in the flexible fabric 1 to form different shapes.
The flexible electrode prepared by the method for manufacturing the flexible electrode based on the fabric can be used as an independent part for collecting the bioelectricity signals and can also be used as an assembly part of a bioelectricity signal collecting system; specifically, the flexible electrode can be applied to but not limited to acquisition of bioelectric signals such as electrocardio, electroencephalogram or myoelectricity;
more specifically, please refer to fig. 5, fig. 5 is a display diagram of the acquisition of the electrocardiosignals by the flexible electrode prepared by the above method, wherein the signals are electrocardiosignals acquired by directly pressing the surface of the electrode layer 4 for five seconds by two fingers, and the abscissa is time and the unit is second; the ordinate is the signal amplitude in microvolts.
Fig. 6 is a display diagram of electroencephalogram signal acquisition of the flexible electrode prepared by the method for manufacturing the flexible electrode based on the fabric according to the first embodiment of the present invention, the signal is an electroencephalogram signal of the positions of AF7 and AF8 based on FPz acquired by directly contacting the forehead scalp AF7, FP1, FPz, FP2, and AF8 through the electrode layer 4, and the abscissa is time and the unit is second; the ordinate is the signal amplitude in microvolts.
In conclusion, the flexible electrode material manufactured by the method for manufacturing the flexible electrode based on the fabric has the characteristics of good conductivity, softness, skin-friendly property, air permeability and the like, and can meet the wearing requirements of users; the electrode layer is prepared on the flexible attachment layer with the thickness of 0.025mm-0.15mm, the electrical property is stable, the surface is smooth, the size stability is good, the flexible electrode formed by the flexible fabric is matched, the surface impedance of the electrode cannot be changed due to stretching in the using process, the stability of the impedance of the electrode is considered while the flexibility is good, the electrode can be tightly attached to the skin in the using process, the tightness is moderate, and the acquired electrical signals are stable and reliable; the electrode prepared by the invention does not need to use gel in the manufacturing and using processes, breaks through the limitation of the flexible electrode on the using time and the using times, and meets the requirement of long-time and multi-frequency use.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent changes made by using the contents of the present specification and the drawings, or applied directly or indirectly to the related technical fields, are included in the scope of the present invention.
Claims (6)
1. A method for manufacturing a flexible electrode based on fabric is characterized by comprising the following steps,
preparing an electrode layer on the electrode adhesion layer with the thickness of 0.025mm-0.15 mm;
attaching the electrode attachment layer to a flexible fabric in a hot pressing mode to form a flexible electrode; electrode adhesion layer with still be equipped with the adhesive linkage between the flexonics, the adhesive linkage is hot melt adhesive net film, a plurality of through-hole has on the hot melt adhesive net film, the through-hole is used for making flexonics with form hollow out construction between the electrode adhesion layer, in order to alleviate electrode adhesion layer receives the tensile influence of flexonics reduces the risk that electrode adhesion layer impedance changes.
2. The method of claim 1, wherein the electrode attachment layer has an elongation of less than 5%.
3. The method for manufacturing the flexible electrode based on the fabric according to claim 1, wherein the pressure of the electrode adhesion layer is maintained for 3 to 10 seconds at a temperature of 130 ℃ to 150 ℃ when the electrode adhesion layer is attached to the flexible fabric by hot pressing.
4. The method of claim 1, wherein the electrode attachment layer is PI or PET.
5. The method of claim 1, wherein the electrode layer is printed on the electrode attachment layer by a printing process.
6. The method of claim 5, wherein the electrode layer is baked at 150 ℃ for 10 minutes or at 130 ℃ for 30 minutes after the electrode layer is formed.
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| CN112998713B true CN112998713B (en) | 2023-04-07 |
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| CN104287698B (en) * | 2014-09-16 | 2016-04-06 | 苏州能斯达电子科技有限公司 | Flexibility for cervical region pulse detection can attach sensor and preparation method thereof |
| CN105455804B (en) * | 2015-11-26 | 2018-09-28 | 苏州明动新材料科技有限公司 | A kind of dry electrode of flexible wearable and preparation method thereof |
| CN106510637A (en) * | 2016-12-01 | 2017-03-22 | 刘青霞 | Stable silk-screen-printing flexible sensor and manufacturing technology thereof |
| CN106859637B (en) * | 2016-12-28 | 2022-05-03 | 电子科技大学 | Flexible conductive rubber electrocardio dry electrode with holes |
| CN208541301U (en) * | 2018-01-05 | 2019-02-26 | 珠海安润普科技有限公司 | A kind of biological fabric pyroelectric monitor electrode |
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