Flexible pressure sensor and preparation method thereof, and wearable device

Abstract

The invention relates to a flexible pressure sensor and a preparation method thereof, and wearable equipment. The flexible pressure sensor comprises a flexible substrate; the interdigital electrode layer is located on the flexible substrate and comprises a first electrode layer, an annular insulating layer and a second electrode layer, the first electrode layer is located on the surface of the flexible substrate and comprises a first annular electrode and a plurality of first sharp-corner-shaped interdigitals sequentially fixed along the inner side wall of the first annular electrode, the annular insulating layer wraps the first annular electrode, and the second electrode layer wraps the second annular electrode; the second electrode layer comprises a second annular electrode and a plurality of second sharp-corner-shaped interdigitals which are sequentially fixed along the inner side wall of the second annular electrode, and the second annular electrode is located on the surface of the flexible substrate on the outer side of the first annular electrode; the second sharp-corner-shaped interdigitals cross the annular insulating layer from the outer sides of the first annular electrodes to extend to the inner sides of the first annular electrodes, and are positioned on the surface of the flexible substrate between the adjacent first sharp-corner-shaped interdigitals; and the pressure sensing layer is positioned on the interdigital electrode layer. The sensitivity and the detection range of the sensor are improved.

Description

Technical Field

[0001] The present application relates to the field of sensors, and in particular to a flexible pressure sensor, a preparation method thereof, and a wearable device. Background Art

[0002] Flexible pressure sensors, due to their bendability, stretchability, and lightweight properties, offer significant advantages over rigid pressure sensors and hold great promise for application in a wide range of fields, including medical diagnosis, tactile sensing, and human-computer interaction. However, during their development, the challenges of sensitivity, detection limit, thickness, and detection range have become increasingly prominent, becoming key constraints on performance improvement and application expansion. While improving sensor performance by introducing microstructures into the sensor's functional layer has improved sensitivity and lowered the detection limit to a certain extent, the issues of thickness and detection range remain unresolved. Summary of the Invention

[0003] Based on this, the present application provides a flexible pressure sensor, a preparation method thereof, and a wearable device, which, while maintaining the thin and lightweight characteristics of the sensor, enables the sensor to have high sensitivity within a wide detection range and be able to adapt to complex shapes and curved surfaces.

[0004] In a first aspect, an embodiment of the present application provides a flexible pressure sensor, comprising:

[0005] Flexible substrate;

[0006] an interdigitated electrode layer located on a flexible substrate, the interdigitated electrode layer comprising a first electrode layer, an annular insulating layer, and a second electrode layer, wherein the first electrode layer is located on the surface of the flexible substrate and comprises a first annular electrode and a plurality of first pointed-angled interdigitated fingers fixed in sequence along an inner sidewall of the first annular electrode, wherein the pointed corners of the first pointed-angled interdigitated fingers point toward a center of the first annular electrode, and the annular insulating layer covers the first annular electrode; the second electrode layer comprises a second annular electrode and a plurality of second pointed-angled interdigitated fingers fixed in sequence along an inner sidewall of the second annular electrode, wherein the pointed corners of the second pointed-angled interdigitated fingers point toward a center of the second annular electrode, and the second annular electrode is located on the surface of the flexible substrate outside the first annular electrode, and the second pointed-angled interdigitated fingers extend from the outside of the first annular electrode across the annular insulating layer to the inside of the first annular electrode, and are located on the surface of the flexible substrate between adjacent first pointed-angled interdigitated fingers;

[0007] The pressure-sensitive layer is located on the interdigital electrode layer.

[0008] In some embodiments of the present application, a plurality of first pointed-angle interdigital fingers are regularly and periodically arranged along the inner sidewall of the first annular electrode; the first pointed-angle interdigital fingers include a first connecting line and a second connecting line arranged at an angle, one end of the first connecting line is connected to one end of the second connecting line to form a sharp corner of the first pointed-angle interdigital finger, the other end of the first connecting line is fixed to the inner sidewall of the first annular electrode, and the other end of the second connecting line is suspended in the air; the height of the first pointed-angle interdigital finger is less than the straight-line distance between the inner sidewall of the first annular electrode and the center of the first annular electrode;

[0009] The first ring-shaped electrode has a first notch, and the second ring-shaped electrode has a second notch.

[0010] In some embodiments of the present application, the angle of the tip of the first pointed-angled fork finger ranges from 30 degrees to 120 degrees.

[0011] In some embodiments of the present application, the angles of the sharp corners of the plurality of first pointed-angled fingers are the same, and the plurality of first pointed-angled fingers have different heights.

[0012] In some embodiments of the present application, in the circumferential direction of the first annular electrode, a first pointed-angled finger with a smaller height is located between two adjacent first pointed-angled fingers with a larger height.

[0013] In some embodiments of the present application, in the radial direction of the first annular electrode, the first pointed-angled fingers with smaller heights are located inside the first pointed-angled fingers with larger heights.

[0014] In some embodiments of the present application, a plurality of second pointed-angled fingers are regularly and periodically arranged along the inner side wall of the second ring electrode; the second pointed-angled fingers include an obliquely arranged third connecting line and a fourth connecting line, one end of the third connecting line is connected to one end of the fourth connecting line to form the tip of the second pointed-angled finger, the other end of the third connecting line is fixed to the inner side wall of the second ring electrode, and the other end of the fourth connecting line is suspended; the height of the second pointed-angled finger is less than the straight-line distance between the inner side wall of the second ring electrode and the center of the second ring electrode.

[0015] In some embodiments of the present application, the angle of the tip of the second pointed-angled finger is equal to the angle of the tip of the first pointed-angled finger; the angle of the tip of the second pointed-angled finger is in the range of 30 degrees to 120 degrees.

[0016] In some embodiments of the present application, the angles of the sharp corners of the plurality of second pointed-angled fingers are the same, and the plurality of second pointed-angled fingers have different heights.

[0017] In some embodiments of the present application, in the circumferential direction of the second annular electrode, a second pointed-angled finger with a smaller height is located between two adjacent second pointed-angled fingers with a larger height.

[0018] In some embodiments of the present application, in the radial direction of the second annular electrode, the second pointed-angled fingers with smaller heights are located inside the second pointed-angled fingers with larger heights.

[0019] In some embodiments of the present application, the flexible pressure sensor further includes: an annular adhesion layer, adhering the pressure sensing layer and the interdigital electrode layer.

[0020] In a second aspect, an embodiment of the present application further provides a method for preparing a flexible pressure sensor, comprising:

[0021] providing a flexible substrate;

[0022] forming an interdigitated electrode layer on a flexible substrate, the interdigitated electrode layer comprising a first electrode layer, an annular insulating layer, and a second electrode layer, wherein the first electrode layer is located on the surface of the flexible substrate and comprises a first annular electrode and a plurality of first pointed-angled interdigitated fingers fixed in sequence along the inner side wall of the first annular electrode, with the pointed corners of the first pointed-angled interdigitated fingers pointing toward the center of the first annular electrode; the annular insulating layer covers the first annular electrode; the second electrode layer comprises a second annular electrode and a plurality of second pointed-angled interdigitated fingers fixed in sequence along the inner side wall of the second annular electrode, with the pointed corners of the second pointed-angled interdigitated fingers pointing toward the center of the second annular electrode; the second annular electrode is located on the surface of the flexible substrate outside the first annular electrode; the second pointed-angled interdigitated fingers extend from the outside of the first annular electrode across the annular insulating layer to the inside of the first annular electrode, and are located on the surface of the flexible substrate between adjacent first pointed-angled interdigitated fingers;

[0023] Providing a prepared pressure-sensitive layer, and superimposing the pressure-sensitive layer on the interdigital electrode layer;

[0024] A prepared annular adhesive layer is provided, and the pressure-sensitive layer and the interdigital electrode layer are adhered together through the annular adhesive layer.

[0025] In some embodiments of the present application, the interdigitated electrode layer is formed by a screen printing process or a direct writing printing technology; the pressure-sensitive layer is prepared by a screen printing process or a direct writing printing technology; and the annular adhesion layer is prepared by a laser cutting process.

[0026] In a third aspect, an embodiment of the present application further provides a wearable device, comprising: the aforementioned pressure sensor, or a pressure sensor prepared by the aforementioned method for preparing a flexible pressure sensor.

[0027] The embodiments of the present application may or at least have the following advantages:

[0028] In an embodiment of the present application, the flexible pressure sensor includes a flexible substrate, an interdigitated electrode layer and a pressure-sensing layer, the interdigitated electrode layer includes a first electrode layer, an annular insulating layer and a second electrode layer, the first electrode layer includes a first annular electrode, and a plurality of first pointed-angled interdigitated fingers fixed in sequence along the inner side wall of the first annular electrode, the pointed corners of the first pointed-angled interdigitated fingers point to the center of the first annular electrode, the second electrode layer includes a second annular electrode, and a plurality of second pointed-angled interdigitated fingers fixed in sequence along the inner side wall of the second annular electrode, the pointed corners of the second pointed-angled interdigitated fingers point to the center of the second annular electrode, and the interdigitated electrode layer also includes an annular insulating layer, the annular insulating layer covers the first annular electrode, the second annular electrode is located on the flexible substrate surface outside the first annular electrode, the second pointed-angled interdigitated fingers extend from the outside of the first annular electrode across the annular insulating layer to the inner side of the first annular electrode, and are located on the flexible substrate surface between adjacent first pointed-angled interdigitated fingers. In the present application, the first electrode layer and the second electrode layer adopt the aforementioned specific shape and specific arrangement, so that the density of the interdigital electrodes in the interdigital electrode layer composed of the first electrode layer and the second electrode layer is increased, thereby increasing the effective contact area between the interdigital electrode layer and the pressure-sensitive layer. The increase in the effective contact area between the interdigital electrode layer and the pressure-sensitive layer can improve the range of change of the current response, which helps to expand the detection upper limit of the flexible pressure sensor. Compared with the conventional interdigital electrode design, when a small stress is applied to the pointed interdigital electrode, due to its unique shape, the initial contact area between the pressure-sensitive layer and the electrode layer is small, so the initial current value is also low. As the applied stress increases, the contact area gradually increases, and the current value also increases significantly. This characteristic causes the pointed interdigital electrode to show higher sensitivity when detecting pressure changes. In addition, the first electrode layer and the second electrode layer are basically located on the surface of the flexible substrate, thereby maintaining the thin and lightweight characteristics of the flexible pressure sensor, and being able to adapt to complex shapes and curves. Furthermore, the first electrode layer, the second electrode layer, and the pressure-sensing layer all employ a planar design, which helps disperse stress, avoids stress concentration problems that exist in flexible pressure sensors, and improves the mechanical stability and service life of the flexible pressure sensor. Polymer materials (such as elastic silicone rubber) are not used throughout the entire preparation process of the flexible pressure sensor, thereby avoiding the problems of delayed response time and prolonged recovery time caused by the viscoelasticity and creep behavior of the polymer. Furthermore, the flexible pressure sensor of the present application is suitable for detecting forces applied by flexible non-planar objects and demonstrates great potential in application scenarios for detecting different forces, such as monitoring object grasping force (including but not limited to grasping a full glass of water, a half-full glass of water, an empty glass, and various weights), impact force (such as a mouse click), and plantar pressure detection. By employing the aforementioned interdigitated electrode layer of a specific shape, the contact quality between the flexible pressure sensor and the object being measured can be improved, thereby improving the accuracy of the detection signal.

[0029] The details of one or more embodiments of the present application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A schematic structural diagram of a flexible pressure sensor provided in some embodiments of the present application;

[0032] Figure 2 A schematic structural diagram of an interdigitated electrode layer in a flexible pressure sensor provided in some embodiments of the present application;

[0033] Figure 3 A schematic structural diagram of an interdigitated electrode layer in a flexible pressure sensor provided in some embodiments of the present application;

[0034] Figure 4 A schematic structural diagram of a conventional interdigitated electrode in a comparative embodiment provided in this application;

[0035] Figure 5 This is a graph showing the relationship between the relative current change and the force value between the conventional interdigital electrode sensor in the comparative embodiment and the 60° angle flexible pressure sensor in the embodiment of the present application;

[0036] Figure 6 This is a signal response diagram of the flexible pressure sensor at a 60° angle in an embodiment of the present application when the same force is applied at different loading speeds;

[0037] Figure 7 The response time and recovery time of the flexible pressure sensor at an angle of 60° in the embodiment of the present application;

[0038] Figure 8 This is a cyclic stability test of the 60° flexible pressure sensor in the embodiment of the present application;

[0039] Figure 9 This is a diagram showing the relationship between the current change and the force value of the flexible pressure sensor at a 30° angle in an embodiment of the present application.

[0040] Description of reference numerals:

[0041] Flexible substrate-101; interdigitated electrode layer-102; pressure-sensitive layer-103; annular adhesive layer-104;

[0042] First electrode layer 12; annular insulating layer 13; second electrode layer 14; first annular electrode 12a; first pointed interdigital finger 12b; second annular electrode 14a; second pointed interdigital finger 14b; first connecting line 12b1; second connecting line 12b2; third connecting line 14b1; third connecting line 14b1. DETAILED DESCRIPTION

[0043] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The drawings provide examples of the present application. However, the present application may be implemented in many different forms and is not limited to the examples described herein. Rather, these examples are provided to make the disclosure of the present application more thorough and comprehensive.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0045] It should be understood that when an element or layer is referred to as being "on, adjacent to, connected to, or coupled to" another element or layer, it can be directly on, adjacent to, connected to, or coupled to the other element or layer, or there can be intervening elements or layers. In contrast, when an element is referred to as being "directly on, directly adjacent to, directly connected to, or directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, doping types, and / or portions, these elements, components, regions, layers, doping types, and / or portions should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, doping type, or portion from another element, component, region, layer, doping type, or portion. Therefore, without departing from the teachings of the present application, the first element, component, region, layer, doping type, or portion discussed below may be represented as a second element, component, region, layer, or portion.

[0046] Spatially relative terms such as "under," "beneath," "beneath," "under," "above," "above," etc., may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, spatially relative terms also include different orientations of the device during use and operation. For example, if the device in the drawings is turned over, the element or feature described as "under" or "beneath" or "beneath" the other elements will be oriented as "over" the other elements or features. Thus, the exemplary terms "under" and "under" can include both the above and below orientations. In addition, the device can also include alternative orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0047] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include," "comprising," "having," and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Also, within this specification, the term "and / or" includes any and all combinations of the relevant listed items.

[0048] The structures of the embodiments of the present application should not be limited to the specific shapes shown in the drawings, but include shape deviations due to, for example, manufacturing technology.

[0049] The embodiment of the present application first provides a flexible pressure sensor. Figure 1 A schematic structural diagram of a flexible pressure sensor provided in some embodiments of the present application; Figure 2 A schematic structural diagram of an interdigitated electrode layer in a flexible pressure sensor provided in some embodiments of the present application.

[0050] refer to Figure 1 Combined with Figure 2 , flexible pressure sensor, including:

[0051] Flexible substrate 101;

[0052] The interdigitated electrode layer 102 is located on the flexible substrate 101. The interdigitated electrode layer 102 includes a first electrode layer 12, an annular insulating layer 13, and a second electrode layer 14. The first electrode layer 12 is located on the surface of the flexible substrate 101 (refer to FIG. Figure 1 ), including a first annular electrode 12a (reference Figure 2), and a plurality of first pointed-angle fork fingers 12b fixed in sequence along the inner side wall of the first annular electrode 12a, wherein the pointed corners of the first pointed-angle fork fingers 12b point to the center of the first annular electrode 12a, the annular insulating layer 13 covers the first annular electrode 12a, and the second electrode layer 14 includes a second annular electrode 14a (refer to Figure 2 ), and a plurality of second pointed fingers 14b are fixed in sequence along the inner side wall of the second annular electrode 14a, the pointed corners of the second pointed fingers 14b point to the center of the second annular electrode 14b, and the second annular electrode 14a (reference Figure 1 ) located on the surface of the flexible substrate 101 outside the first annular electrode 12a, the second pointed fingers 14b extending from the outside of the first annular electrode 12a across the annular insulating layer 13 to the inside of the first annular electrode 12a, and located on the surface of the flexible substrate 101 between adjacent first pointed fingers 12b;

[0053] The pressure-sensitive layer 103 is located on the interdigital electrode layer 102 .

[0054] The flexible substrate 101 includes opposite top and bottom surfaces. The interdigitated electrode layer 102 is located on the top surface of the flexible substrate 101 . In one example, the material of the flexible substrate 101 includes polyethylene terephthalate (PET), polydimethylsiloxane (PDMS) or polyimide (PI).

[0055] The interdigitated electrode layer 102 includes a first electrode layer 12, an annular insulating layer 13, and a second electrode layer 14. The annular insulating layer 13 is used to electrically isolate the first and second electrode layers 14. When the pressure-sensitive layer 103 is deformed by external pressure and contacts the first and second electrode layers 12, 14, a contact resistance is generated between the first and second electrode layers 12, 14. The magnitude of this contact resistance is related to the magnitude of the external pressure. As the external pressure increases, the deformation of the pressure-sensitive layer 103 increases, causing the contact area between the pressure-sensitive layer 103 and the first and second electrode layers 12, 14 to increase, thereby decreasing the contact resistance.

[0056] In the flexible pressure sensor of the present application, the first electrode layer 12 in the interdigitated electrode layer 102 includes a first annular electrode 12a (refer to Figure 2 ), and a plurality of first pointed-angle interdigits 12b fixed in sequence along the inner side wall of the first annular electrode 12a, wherein the pointed corners of the first pointed-angle interdigits 12b point to the center of the first annular electrode 12a, and the second electrode layer 14 in the interdigitated electrode layer 102 includes a second annular electrode 14a (refer to Figure 2), and a plurality of second pointed fingers 14b fixed in sequence along the inner side wall of the second annular electrode 14a, the pointed corners of the second pointed fingers 14b point to the center of the second annular electrode 14b, and the finger electrode layer 102 further includes an annular insulating layer, the annular insulating layer 13 covers the first annular electrode 12a (refer to Figure 1 ), the second annular electrode 14a (reference Figure 1 ) is located on the surface of the flexible substrate 101 outside the first annular electrode 12a, and the second pointed interdigitated fingers 14b extend from the outside of the first annular electrode 12a across the annular insulating layer 13 to the inside of the first annular electrode 12a, and are located on the surface of the flexible substrate 101 between adjacent first pointed interdigitated fingers 12b. In the present application, the first electrode layer 12 and the second electrode layer 14 adopt the aforementioned specific shape and specific arrangement, so that the density of the interdigitated electrodes in the interdigitated electrode layer 102 composed of the first electrode layer 12 and the second electrode layer 14 is increased, thereby increasing the effective contact area between the interdigitated electrode layer 102 and the pressure-sensitive layer 103. The increase in the effective contact area between the interdigitated electrode layer 102 and the pressure-sensitive layer 103 can increase the range of change of the current response, which helps to expand the detection upper limit of the flexible pressure sensor. Compared to conventional interdigital electrode designs, the pointed interdigital electrodes (including the first and second pointed interdigital fingers 12b, 14b) have a unique shape that reduces the initial contact area between the pressure-sensing layer 103 and the interdigital electrode layer 102 when subjected to low stress, resulting in a lower initial current. As the applied stress increases, the contact area gradually increases, and the current value also increases significantly. This characteristic results in the pointed interdigital electrodes exhibiting greater sensitivity when detecting pressure changes. Furthermore, the first and second electrode layers 12, 14 are essentially located on the surface of the flexible substrate 101, thus maintaining the thinness and lightweight characteristics of the flexible pressure sensor and enabling it to adapt to complex shapes and curved surfaces. Furthermore, the first and second electrode layers 12, 14, and pressure-sensing layer 103 all adopt a planar design, which helps disperse stress, avoids the stress concentration problem that often occurs in flexible pressure sensors, and improves the mechanical stability and service life of the flexible pressure sensor. At the same time, no polymer materials (such as elastic silicone rubber, etc.) are used in the entire preparation process of the flexible pressure sensor, thereby avoiding the problems of delayed response time and extended recovery time caused by the viscoelasticity and creep behavior of the polymer. In addition, the flexible pressure sensor of the present application is suitable for detecting the force applied by flexible non-planar objects, and has shown great potential in application scenarios of detecting different forces, such as monitoring the grasping force of objects (including but not limited to grasping a full glass of water, a half-full glass of water, an empty glass, and various weights), knocking force (such as mouse clicks), and plantar pressure detection. By using the aforementioned interdigital electrode layer 102 of a specific shape, the contact quality between the flexible pressure sensor and the object being measured can be improved, thereby improving the accuracy of the detection signal.

[0057] The first ring electrode 12a and the second ring electrode 14a can be designed into different shapes according to different application scenarios. The first ring electrode 12a and the second ring electrode 14a have the same shape. Figure 2 The first ring electrode 12a and the second ring electrode 14a are in the shape of a circular ring, and the center of the first ring electrode 12a and the second ring electrode 14a is the center of the circular ring. In other embodiments, the first ring electrode 12a and the second ring electrode 14a can be in the shape of a regular polygonal ring, such as a square ring, a rectangular ring, a pentagonal ring, or a hexagonal ring.

[0058] In some embodiments, continue to refer to Figure 2 The first electrode layer 12 also includes a first lead-out electrode 12c electrically connected to the first ring electrode 12a, and the second electrode layer 14 also includes a second lead-out electrode 14c electrically connected to the second ring electrode 14a. The first lead-out electrode 12c and the second lead-out electrode 14c are both located on the surface of the flexible substrate 101, and the first lead-out electrode 12c and the second lead-out electrode 14c are staggered with each other.

[0059] In some embodiments, continue to refer to Figure 2 , the first ring-shaped electrode 12a has a first notch; a plurality of first pointed-angle forked fingers 12b are regularly and periodically arranged along the inner side wall of the first ring-shaped electrode 12a; the first pointed-angle forked fingers 12b include a first connecting line 12b1 and a second connecting line 12b2 that are arranged obliquely, one end of the first connecting line 12b1 is connected to one end of the second connecting line 12b2 to form a sharp angle A1 of the first pointed-angle forked finger 12b, the other end of the first connecting line 12b1 is fixed to the inner side wall of the first ring-shaped electrode 12a, and the other end of the second connecting line 12b2 is suspended (not connected to the first ring-shaped electrode 12a); the height H1 of the first pointed-angle forked finger 12b is less than the straight-line distance R1 between the inner side wall of the first ring-shaped electrode 12a and the center 15 of the first ring-shaped electrode 12a, and the angles of the sharp angles of the plurality of first pointed-angle forked fingers 12b in the first electrode layer 12 are the same, and the plurality of first pointed-angle forked fingers 12b have different heights H1. In a specific example, with reference to Figure 2 or Figure 3 In the circumferential direction of the first annular electrode 12a, the first pointed interdigital finger 12b with a smaller height is located between two first pointed interdigital fingers 12b with a larger height. For example, in the circumferential direction of the first annular electrode 12a, the first pointed interdigital finger 12b with a first height is located between two first pointed interdigital fingers 12b with a second height, and the first height is smaller than the second height. In another specific example, referring to Figure 2In the circumferential direction of the first annular electrode 12a, some first pointed fingers 12b of smaller height are located between two adjacent first pointed fingers 12b of larger height, and in the radial direction of the first annular electrode 12a, some first pointed fingers 12b of smaller height are located within the first pointed fingers 12b of larger height. For example, in the circumferential direction of the first annular electrode 12a, some first pointed fingers 12b of first height are located between two adjacent first pointed fingers 12b of second height, and in the radial direction of the first annular electrode 12a, some first pointed fingers 12b of first height are located within the first pointed fingers 12b of second height, with the first height being less than the second height. Through the aforementioned specific configuration, the layout of the first pointed fingers 12b is further optimized, the distribution density of the first electrode layer 12 per unit area is further increased, the effective contact area between the first electrode layer 12 and the pressure-sensing layer 103 is further increased, and the distribution of the sensing area is further changed, thereby further improving the sensitivity and detection range of the flexible pressure sensor.

[0060] In some embodiments, the angle range of the sharp angle A1 of the first sharp-angled fork finger 12b is 30 degrees to 120 degrees, and can be specifically 30 degrees, 45 degrees, 60 degrees, 90 degrees, or 120 degrees. Figure 2 The angle of the first pointed angle A1 of the first pointed fork finger 12b is 60 degrees. In another specific example, referring to Figure 3 The angle of the sharp corner of the first pointed fork finger 12b is 30 degrees.

[0061] In some embodiments, continue to refer to Figure 2 , the second ring-shaped electrode 14a has a second gap; a plurality of second pointed-angle forked fingers 14b are regularly and periodically arranged along the inner side wall of the second ring-shaped electrode 14a; the second pointed-angle forked fingers 14b include an inclined third connecting line 14b1 and a third connecting line 14b1, one end of the third connecting line 14b1 is connected to one end of the fourth connecting line 14b2 to form a sharp angle A2 of the second pointed-angle forked finger 14b, the other end of the third connecting line 14b1 is fixed to the inner side wall of the second ring-shaped electrode 14a, and the other end of the fourth connecting line 14b2 is suspended (not connected to the second ring-shaped electrode 14a); the height H2 of the second pointed-angle forked finger 14b is less than the straight-line distance R2 between the inner side wall of the second ring-shaped electrode 14a and the center 16 of the second ring-shaped electrode 14a, and the angles of the sharp angles of the plurality of second pointed-angle forked fingers 14b in the second electrode layer 14 are the same, and the plurality of second pointed-angle forked fingers 14b have different heights. In a specific example, with reference to Figure 2 or Figure 3In the circumferential direction of the second annular electrode 14a, the second pointed angular interdigit 14b with a smaller height is located between two adjacent second pointed angular interdigits 14b with a larger height. For example, a second pointed angular interdigit 14b with a first height is located between two adjacent second pointed angular interdigits 14b with a second height, and the first height is smaller than the second height. In another specific example, referring to Figure 2 In the circumferential direction of the second annular electrode 14a, some of the second pointed fingers 14b with smaller heights are located between two adjacent second pointed fingers 14b with larger heights, and in the radial direction of the second annular electrode 14a, some of the second pointed fingers 14b with smaller heights are located within the second pointed fingers 14b with larger heights. For example, in the circumferential direction of the second annular electrode 14a, some of the second pointed fingers 14b with a first height are located between two adjacent second pointed fingers 14b with a second height, and in the radial direction of the second annular electrode 14a, some of the second pointed fingers 14b with a first height are located within the second pointed fingers 14b with a second height, with the first height being less than the second height. Through the aforementioned specific configuration, the layout of the second pointed fingers 14b is further optimized, the distribution density of the second electrode layer 14 per unit area is further increased, the effective contact area between the second electrode layer 14 and the pressure-sensitive layer 103 is further increased, and the distribution of the sensing area is further changed, thereby further improving the sensitivity and detection range of the flexible pressure sensor.

[0062] In some embodiments, the center 16 of the second ring electrode 14a in the interdigitated electrode layer 102 coincides with the center 15 of the first ring electrode 12a, and the angle of the sharp angle A1 of the second pointed interdigitated finger 14b is equal to the angle of the sharp angle A2 of the first pointed interdigitated finger 12b, so that the second pointed interdigitated finger 14b is arranged between adjacent first pointed interdigitated fingers 12b, thereby improving the uniformity of the distribution of the second pointed interdigitated finger 14b and the first pointed interdigitated finger 12b, and facilitating further improvement of the sensitivity and response speed of the flexible pressure sensor; the angle range of the sharp angle of the second pointed interdigitated finger 14b is 30 degrees to 120 degrees, and can be specifically 30 degrees, 45 degrees, 60 degrees, 90 degrees, or 120 degrees. In a specific example, reference Figure 2 The angle of the sharp angle A2 of the second pointed fork finger 14b is 60 degrees. In another specific example, referring to Figure 3 The angle of the sharp corner of the second pointed fork finger 14b is 30 degrees.

[0063] In some embodiments, the second ring electrode 14a and the first ring electrode 12a are both annular, and the diameter (outer diameter) of the second ring electrode 14a is larger than the diameter (outer diameter) of the first ring electrode 12a. In one example, the diameter range of the second ring electrode 14a is 16 mm-18 mm, and specifically the diameter of the second ring electrode 14a can be 16 mm, 17 mm, or 18 mm. The diameter range of the first ring electrode 12a is 14 mm-16 mm, and specifically the diameter of the first ring electrode 12a can be 14 mm, 15 mm, or 16 mm. The line width of the first ring electrode 12a, the line width of the first pointed-angled interdigit 12b, the line width of the second ring electrode 14a, and the line width of the second pointed-angled interdigit 14b are all equal. The line width of the first ring electrode 12a, the line width of the first pointed-angled interdigit 12b, the line width of the second ring electrode 14a, and the line width of the second pointed-angled interdigit 14b are in the range of 0.2 mm. -0.4mm, specifically 0.2 mm, 0.25 mm, 0.3 mm, 0.32 mm, 0.34 mm, 0.36 mm, 0.38 mm, 0.4 mm, the spacing between the first pointed-angled finger 12b and the adjacent second pointed-angled finger 14b ranges from 0.35mm to 0.5mm, specifically 0.35 mm, 0.38 mm, 0.4 mm, 0.46 mm, 0.48 mm, 0.5mm.

[0064] The first electrode layer 12 and the second electrode layer 14 are made of highly conductive materials. In one example, highly conductive materials include conductive metals, conductive polymers, metal nanowires, and conductive carbon materials. Conductive metals include gold, silver, copper, aluminum, and nickel. Conductive polymers include poly (3,4-ethylenedioxythiophene / polystyrene sulfonate) (PEDOT:PSS) and polyaniline. Metal nanowires include gold nanowires, silver nanowires, and copper nanowires. Conductive carbon materials include carbon nanotubes, graphene, and graphite sheets. In some embodiments, the first electrode layer 12 and the second electrode layer 14 can be made of highly conductive silver paste or highly conductive carbon paste.

[0065] The annular insulating layer 13 is used for electrical isolation between the first electrode layer and the second electrode layer 14. The annular insulating layer 13 is annular and has a third notch, and the position of the third notch corresponds to the position of the first notch. The annular insulating layer 13 covers the first annular electrode 12a, including: the annular insulating layer 13 covers the upper surface and side surface of the first annular electrode 12a. The line width of the annular insulating layer 13 is greater than the line width of the first annular electrode 12a. In one example, the line width of the annular insulating layer 13 is 0.9 mm-1.1 mm, specifically 0.9 mm, 1 mm, and 1.1 mm. In some embodiments, the material of the annular insulating layer 13 includes insulating ink, such as epoxy resin ink, polyurethane ink, acrylic ink, chlorovinyl resin and polyurethane composite ink, etc.

[0066] The shape and size of the pressure-sensitive layer 103 are the same as those of the second electrode layer 14. The pressure-sensitive layer 103 includes a second flexible substrate and a conductive layer located on the second flexible substrate near the surface of the second electrode layer 14. The second flexible substrate can be made of polyethylene terephthalate (PET), polydimethylsiloxane (PDMS), or polyimide (PI), and the conductive layer can be made of conductive carbon paste or a graphene composite material.

[0067] The flexible pressure sensor also includes an annular adhesive layer 104, which adheres the pressure-sensing layer 103 to the interdigital electrode layer 102. Specifically, the annular adhesive layer 104 adheres the pressure-sensing layer 103 to the second pointed interdigital fingers 14b on the annular insulating layer 13 of the interdigital electrode layer 102. The annular adhesive layer 104 has a fourth notch. In one example, the outer diameter of the annular adhesive layer 104 is 18 mm, the inner diameter is 14 mm, and the fourth notch is 2 mm. The material of the annular adhesive layer 104 includes double-sided tape, double-sided adhesive tape, or hot-melt adhesive film.

[0068] The present application also provides a method for preparing a flexible pressure sensor, referring to Figure 1 Combined with reference Figure 2 ,include:

[0069] Providing a flexible substrate 101;

[0070] An interdigitated electrode layer 102 is formed on the flexible substrate 101. The interdigitated electrode layer includes a first electrode layer 12, an annular insulating layer 13, and a second electrode layer 14. The first electrode layer 12 is located on the surface of the flexible substrate 101 and includes a first annular electrode 12a (refer to Figure 2 ), and a plurality of first pointed-angle fork fingers 12b fixed in sequence along the inner side wall of the first annular electrode 12a, wherein the pointed corners of the first pointed-angle fork fingers 12b point to the center of the first annular electrode 12a, the annular insulating layer 13 covers the first annular electrode 12a, and the second electrode layer 14 includes a second annular electrode 14a (refer to Figure 2), and a plurality of second pointed-angled interdigits 14b sequentially fixed along the inner side wall of the second annular electrode 14a, wherein the pointed corners of the second pointed-angled interdigits 14b point toward the center of the second annular electrode 14b, and the second annular electrode 14a is located on the surface of the flexible substrate 101 outside the first annular electrode 12a, and the second pointed-angled interdigits 14b extend from the outside of the first annular electrode 12a across the annular insulating layer 13 to the inside of the first annular electrode 12a, and are located on the surface of the flexible substrate 101 between adjacent first pointed-angled interdigits 12b;

[0071] Providing a prepared pressure-sensitive layer 103, and superimposing the pressure-sensitive layer 103 on the interdigital electrode layer 102;

[0072] A prepared annular adhesive layer 104 is provided, and the pressure-sensitive layer 103 and the interdigital electrode layer 102 are adhered together through the annular adhesive layer 104 .

[0073] In some embodiments, forming the interdigitated electrode layer 102 includes: according to the design drawings of the first electrode layer 12, the annular insulating layer 13 and the second electrode layer 14, respectively completing the preparation of a high-precision first electrode layer screen, annular insulating layer screen and second electrode layer screen; performing a first screen printing process, using a conductive silver paste as a raw material, using the first electrode layer screen to print the first electrode layer 12 onto the flexible substrate 101, and then performing a first drying process, the temperature of the first drying process is 115°C-125°C, and the time is 10 minutes-20 minutes, specifically 120°C, 15 minutes; performing a second screen printing process, using a chlorovinyl resin and polyurethane composite ink as raw materials, aligning the annular insulating layer screen with the first electrode layer 12 through a positioning mark, and then the annular insulating layer 13 is placed on the flexible substrate 101. Printing is performed to cover the first annular electrode 12a, and then a second drying process is performed. The temperature of the second drying process is 115°C-125°C, and the time is 10 minutes-20 minutes, specifically 120°C, 15 minutes; a third screen printing process is performed, using conductive silver paste as raw material, and after aligning the second electrode layer screen with the first electrode layer 12 through positioning marks, the second electrode layer 14 is printed on the flexible substrate 101 and the annular insulating layer 13, and then a third drying process is performed. The temperature of the third drying process is 115°C-125°C, and the time is 10 minutes-20 minutes, specifically 120°C, 15 minutes. In other embodiments, direct writing printing technology can be used to form the first electrode layer 12, the annular insulating layer 13, and the second electrode layer 14.

[0074] In some embodiments, preparing the pressure-sensitive layer 103 includes: preparing a screen printing plate according to the pressure-sensitive layer pattern design; providing a second flexible substrate; printing a conductive carbon paste on the second flexible substrate using the screen printing plate to form a conductive layer; and then drying the conductive layer at a temperature of 115°C to 125°C for 0.9 to 1.1 hours, specifically 120°C for 1 hour. In one embodiment, the resistance of the conductive layer prepared is 200 kΩ to 260 kΩ, specifically 250 kΩ. In other embodiments, the conductive layer can be formed using direct write printing technology.

[0075] In some embodiments, the annular adhesive layer 104 is prepared by a laser cutting process.

[0076] It should be noted that the limitations or descriptions of the same or similar parts in this embodiment (method for preparing a flexible pressure sensor) and the aforementioned embodiment (flexible pressure sensor) will not be repeated in this embodiment. Please refer to the limitations or descriptions of the corresponding parts in the aforementioned embodiment for details.

[0077] The present application also provides a wearable device comprising the aforementioned pressure sensor, or a pressure sensor prepared using the aforementioned method for preparing a flexible pressure sensor. The wearable device is suitable for detecting the force applied by a flexible non-planar object, such as detecting finger touch force or plantar pressure distribution.

[0078] In some embodiments, the wearable device includes smart shoes, control gloves, wristbands, neckbands, watches, etc.

[0079] Finally, the flexible pressure sensor of the present application or the pressure sensor prepared by the aforementioned preparation method will be further described in conjunction with specific embodiments and comparative examples, but they should not be understood as limiting the scope of protection of the present application.

[0080] Example 1, reference Figure 1 Combined with reference Figure 2 , a flexible pressure sensor, comprising:

[0081] Flexible substrate 101;

[0082] The interdigitated electrode layer 102 is located on the flexible substrate 101. The interdigitated electrode layer includes a first electrode layer 12, an annular insulating layer 13, and a second electrode layer 14. The first electrode layer 12 is located on the surface of the flexible substrate 101 (refer to Figure 1 ), including a first annular electrode 12a (reference Figure 2 ), and a plurality of first pointed-angle fork fingers 12b fixed in sequence along the inner side wall of the first annular electrode 12a, wherein the pointed corners of the first pointed-angle fork fingers 12b point to the center of the first annular electrode 12a, the annular insulating layer 13 covers the first annular electrode 12a, and the second electrode layer 14 includes a second annular electrode 14a (refer to Figure 2 ), and a plurality of second pointed fingers 14b are fixed in sequence along the inner side wall of the second annular electrode 14a, the pointed corners of the second pointed fingers 14b point to the center of the second annular electrode 14b, and the second annular electrode 14a (reference Figure 1 ) is located on the surface of the flexible substrate 101 outside the first annular electrode 12a, the second pointed interdigital fingers 14b extend from the outside of the first annular electrode 12a across the annular insulating layer 13 to the inside of the first annular electrode 12a, and are located on the surface of the flexible substrate 101 between adjacent first pointed interdigital fingers 12b, and the angle of the pointed angle A1 of the first pointed interdigital fingers 12b is 60 degrees. The diameter of the first annular electrode 12a is 15 mm, and the diameter of the second annular electrode 14a may be 17 mm. The line width of the first annular electrode 12a, the line width of the first pointed interdigital fingers 12b, the line width of the second annular electrode 14a, and the line width of the second pointed interdigital fingers 14b are all 0.32 mm, and the spacing between a first pointed interdigit 12b and an adjacent second pointed interdigit 14b is 0.43 mm;

[0083] The pressure-sensitive layer 103 is located on the interdigital electrode layer 102 and has a diameter of 17 mm;

[0084] The annular adhesive layer 104 adheres the pressure-sensitive layer 103 and the interdigitated electrode layer 102 . The annular adhesive layer 104 has a fourth gap. The outer diameter of the annular adhesive layer 104 is 18 mm, the inner diameter is 14 mm, and the size of the fourth gap is 2 mm.

[0085] Example 2, a flexible pressure sensor, referring to Figure 3 Compared with embodiment 1, the main difference is that the angle of the sharp angle A1 of the first pointed fork finger 12b is 30 degrees.

[0086] Comparative Example 1, a conventional flexible pressure sensor, reference Figure 4 , including: an interdigital electrode 112, the interdigital electrode 112 includes a first interdigital electrode 21 and a second interdigital electrode 22, the line width of the first interdigital electrode 21 and the second interdigital electrode 22 is 0.32 mm, the spacing between the first interdigital electrode 21 and the second interdigital electrode 22 is 0.43 mm, and the diameter of the interdigital electrode 112 is 17 mm; a pressure-sensitive layer (not shown in the figure), located on the interdigital electrode 112, the diameter of the pressure-sensitive layer is 17 mm; an adhesion layer (not shown in the figure), one side of the adhesion layer is bonded to the electrode layer, and the other side is bonded to the pressure-sensitive layer.

[0087] The performance of the flexible pressure sensors in Examples 1 and 2 and the conventional flexible pressure sensor in Comparative Example 1 was tested.

[0088] in, Figure 5The relationship between the relative current change and force value of the conventional interdigital electrode sensor in Example 1 and the flexible pressure sensor in Example 1 is shown in FIG. Figure 5 It can be seen from the figure that the sensitivity of the flexible pressure sensor of the present application is higher than that of the conventional interdigital electrode sensor.

[0089] Figure 6 The signal response diagram of the flexible pressure sensor in Example 1 when the same force is applied at different loading speeds (2.5 mm / min, 5 mm / min, 10 mm / min, 20 mm / min) is shown in FIG. Figure 6 It can be seen that when the same force is applied at different loading speeds, the signal response intensity of the sensor is consistent, indicating that the sensor has good reliability.

[0090] Figure 7 is the response time and recovery time of the flexible pressure sensor in Example 1, Figure 7 It can be seen that the flexible pressure sensor of the present application has a fast response time and recovery time, with a signal response time of 62.6 ms and a recovery time of 100 ms.

[0091] Figure 8 The cyclic stability test of the flexible pressure sensor in Example 1 is performed by Figure 8 It can be seen that the flexible pressure sensor of the present application still maintains a stable signal output after undergoing 1000 cycles of compression, indicating that it has high stability.

[0092] Figure 9 This is a relationship diagram between the current change and the force value of the flexible pressure sensor in Example 2. The flexible pressure sensor of the present application has a high sensitivity.

[0093] Throughout this specification, references to terms such as "some embodiments," "other embodiments," and "desired embodiments" mean that a particular feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present application. Within this specification, the illustrative descriptions of these terms do not necessarily refer to the same embodiment or example.

[0094] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0095] The above embodiments merely illustrate several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A flexible pressure sensor, characterized in that: include: Flexible substrate; an interdigitated electrode layer located on the flexible substrate, the interdigitated electrode layer comprising a first electrode layer, an annular insulating layer, and a second electrode layer, wherein the first electrode layer is located on the surface of the flexible substrate and comprises a first annular electrode and a plurality of first pointed-angled interdigitated fingers fixed in sequence along the inner sidewall of the first annular electrode, wherein the pointed corners of the first pointed-angled interdigitated fingers point toward the center of the first annular electrode, and the annular insulating layer covers the first annular electrode; the second electrode layer comprises a second annular electrode and a plurality of second pointed-angled interdigitated fingers fixed in sequence along the inner sidewall of the second annular electrode, wherein the pointed corners of the second pointed-angled interdigitated fingers point toward the center of the second annular electrode, and the second annular electrode is located on the surface of the flexible substrate outside the first annular electrode, and the second pointed-angled interdigitated fingers extend from the outside of the first annular electrode across the annular insulating layer to the inside of the first annular electrode, and are located on the surface of the flexible substrate between adjacent first pointed-angled interdigitated fingers; The pressure-sensitive layer is located on the interdigital electrode layer.

2. The flexible pressure sensor according to claim 1, characterized in that A plurality of first pointed-angle interdigital fingers are regularly and periodically arranged along the inner sidewall of the first annular electrode; the first pointed-angle interdigital fingers include a first connecting line and a second connecting line arranged obliquely, one end of the first connecting line is connected to one end of the second connecting line to form a sharp corner of the first pointed-angle interdigital finger, the other end of the first connecting line is fixed to the inner sidewall of the first annular electrode, and the other end of the second connecting line is suspended in the air; the height of the first pointed-angle interdigital fingers is less than the straight-line distance between the inner sidewall of the first annular electrode and the center of the first annular electrode; The first ring-shaped electrode has a first notch, and the second ring-shaped electrode has a second notch.

3. The flexible pressure sensor according to claim 2, characterized in that: The angle of the first pointed-angle fork finger is in the range of 30 degrees to 120 degrees.

4. The flexible pressure sensor according to claim 3, characterized in that: The angles of the sharp corners of the plurality of first pointed-angled fingers are the same, and the plurality of first pointed-angled fingers have different heights.

5. The flexible pressure sensor according to claim 4, characterized in that: In the circumferential direction of the first annular electrode, the first pointed-angled fork finger with a smaller height is located between two adjacent first pointed-angled fork fingers with a larger height.

6. The flexible pressure sensor according to claim 3 or 4, characterized in that: In the radial direction of the first annular electrode, the first pointed-angled fingers with smaller heights are located inside the first pointed-angled fingers with larger heights.

7. The flexible pressure sensor according to claim 2, characterized in that: A plurality of second pointed-angled fingers are regularly and periodically arranged along the inner side wall of the second ring-shaped electrode; the second pointed-angled fingers include an obliquely arranged third connecting line and a fourth connecting line, one end of the third connecting line is connected to one end of the fourth connecting line to form the tip of the second pointed-angled finger, the other end of the third connecting line is fixed to the inner side wall of the second ring-shaped electrode, and the other end of the fourth connecting line is suspended in the air; the height of the second pointed-angled finger is less than the straight-line distance between the inner side wall of the second ring-shaped electrode and the center of the second ring-shaped electrode.

8. The flexible pressure sensor according to claim 7, characterized in that: The angle of the tip of the second pointed-angled fork finger is equal to the angle of the tip of the first pointed-angled fork finger; the angle of the tip of the second pointed-angled fork finger ranges from 30 degrees to 120 degrees.

9. The flexible pressure sensor according to claim 8, characterized in that: The angles of the sharp corners of the plurality of second pointed-angled fingers are the same, and the plurality of second pointed-angled fingers have different heights.

10. The flexible pressure sensor according to claim 9, characterized in that: In the circumferential direction of the second annular electrode, the second pointed-angled fork finger with a smaller height is located between two adjacent second pointed-angled fork fingers with a larger height.

11. The flexible pressure sensor according to claim 9 or 10, characterized in that: In the radial direction of the second annular electrode, the second pointed-angled fork finger with a smaller height is located inside the second pointed-angled fork finger with a larger height.

12. The flexible pressure sensor according to claim 1, characterized in that The flexible pressure sensor further includes: an annular adhesive layer, adhering the pressure sensing layer and the interdigital electrode layer.

13. A method for preparing a flexible pressure sensor, characterized in that: include: providing a flexible substrate; forming an interdigitated electrode layer on the flexible substrate, the interdigitated electrode layer comprising a first electrode layer, an annular insulating layer, and a second electrode layer, wherein the first electrode layer is located on the surface of the flexible substrate and comprises a first annular electrode and a plurality of first pointed-angled interdigitated fingers fixed in sequence along the inner sidewall of the first annular electrode, with the pointed corners of the first pointed-angled interdigitated fingers pointing toward the center of the first annular electrode; the annular insulating layer covers the first annular electrode; the second electrode layer comprises a second annular electrode and a plurality of second pointed-angled interdigitated fingers fixed in sequence along the inner sidewall of the second annular electrode, with the pointed corners of the second pointed-angled interdigitated fingers pointing toward the center of the second annular electrode, and the second annular electrode is located on the surface of the flexible substrate outside the first annular electrode, the second pointed-angled interdigitated fingers extend from the outside of the first annular electrode across the annular insulating layer to the inside of the first annular electrode, and are located on the surface of the flexible substrate between adjacent first pointed-angled interdigitated fingers; Providing a prepared pressure-sensitive layer, and superimposing the pressure-sensitive layer on the interdigital electrode layer; A prepared annular adhesive layer is provided, and the pressure-sensitive layer and the interdigital electrode layer are adhered to each other through the annular adhesive layer.

14. The method for preparing a flexible pressure sensor according to claim 13, wherein: The interdigitated electrode layer is formed by screen printing or direct writing; the pressure-sensitive layer is prepared by screen printing or direct writing; and the annular adhesive layer is prepared by laser cutting.

15. A wearable device, characterized in that: include: The pressure sensor according to any one of claims 1 to 12, or a pressure sensor prepared by the method for preparing a flexible pressure sensor according to any one of claims 13 to 14.

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