Pressure sensitive conductive film
By designing a pressure-sensitive conductive film, an isolation layer is used to isolate the upper and lower carbon powder layers in the absence of pressure, and conduction is achieved when pressure is applied. This solves the defects of traditional mechanical switches and non-contact sensors, and realizes a conductive film structure with high sensitivity, low energy consumption and high reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HAINING DAYUAN ELECTRONICS
- Filing Date
- 2025-07-29
- Publication Date
- 2026-07-07
Smart Images
Figure CN224471172U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a conductive film, and more particularly to a pressure-sensitive conductive film. Background Technology
[0002] Traditional mechanical switches suffer from physical wear and tear, limited lifespan, poor water resistance, require direct physical pressing operation, and have relatively high standby power consumption.
[0003] Non-contact sensors such as capacitive and infrared sensors are expensive, have complex circuits, and are easily affected by environmental interference or false triggering.
[0004] Existing pressure sensing materials or structures may have problems such as a small resistance variation range, limited trigger points, and relatively low sensing sensitivity. Utility Model Content
[0005] To solve the above problems, this utility model provides a pressure-sensitive conductive film, the specific technical solution of which is as follows:
[0006] A pressure-sensitive conductive film includes, from top to bottom, an upper film layer, an upper silver powder layer, an upper carbon powder layer, an isolation layer, a lower carbon powder layer, a lower silver powder layer, and a lower film layer. In a free state, the isolation layer isolates the upper carbon powder layer from the lower carbon powder layer or ensures that the contact area between the upper and lower carbon powder layers is less than the conductive area. When the isolation layer is subjected to pressure, the contact area between the upper and lower carbon powder layers becomes greater than the conductive area, thus enabling the upper and lower silver powder layers to conduct.
[0007] Preferably, the upper silver powder layer is provided with a plurality of first wires, a plurality of second wires, a first lead and a second lead, the first wires and the second wires being arranged in parallel and interleaved in sequence, the first wires being connected to the first lead, and the second wires being connected to the second lead;
[0008] The lower silver powder layer is provided with a plurality of third conductors, a plurality of fourth conductors, a third lead, and a fourth lead. The third conductors and the fourth conductors are arranged in parallel and staggered order. All third conductors are connected to the third lead, and all fourth conductors are connected to the fourth lead.
[0009] Furthermore, both the first and second conductors are arranged to intersect with the third and fourth conductors.
[0010] Furthermore, both the first and second conductors are arranged perpendicularly to the third and fourth conductors.
[0011] Preferably, the isolation layer includes a plurality of isolation blocks, which are disposed on the upper toner layer or the lower toner layer and are used to isolate the upper toner layer and the lower toner layer in a free state.
[0012] Furthermore, the isolation blocks are evenly distributed on the upper toner layer or the lower toner layer.
[0013] Preferably, the thickness of the upper film layer is greater than the thickness of the lower film layer.
[0014] Furthermore, the thickness of the upper film layer is 0.3~0.4mm, and the thickness of the lower film layer is 0.1~0.2mm.
[0015] Preferably, it also includes a backing adhesive layer disposed below the lower film layer.
[0016] Compared with the prior art, the present invention has the following beneficial effects:
[0017] The pressure-sensitive conductive membrane provided by this utility model has a simple structure, good waterproof performance, low standby power consumption, low cost, and high sensitivity.
[0018] Pressure-sensitive conductive films have a simple structure, reliable performance, and are easy to integrate.
[0019] When there is no pressure, the circuit is reliably disconnected (high resistance state), isolating the power signal, effectively reducing standby power consumption, and ensuring product safety. When not in use, the circuit automatically shuts off to prevent product malfunctions when not in use.
[0020] When under pressure, the circuit reliably conducts (low resistance state) to enable automatic startup or function triggering of the equipment.
[0021] Reduce manual pressing operations to make it easier for people and animals that cannot operate independently.
[0022] The pressure-sensitive conductive membrane can automatically switch the power on and off, meaning it automatically turns on when in use (under pressure) and automatically turns off when not in use (under no pressure), avoiding repeated manual operation of the switch and effectively saving standby power consumption. It is especially suitable for products with high safety requirements (such as heating pads), preventing the product from malfunctioning when not in use (a malfunctioning heating pad can cause the product to overheat and burn).
[0023] It features high precision and high sensitivity. Due to the densely packed trigger points, it responds quickly to pressure changes (the pressure can be adjusted according to the actual product requirements) and will not be falsely triggered by environmental interference (capacitive, infrared and other non-contact sensors are prone to false triggering). Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the structure of this application;
[0025] Figure 2 This is an assembly diagram of the upper film layer, upper silver powder layer, upper carbon powder layer and isolation block;
[0026] Figure 3 This is an assembly diagram of the lower film layer, lower silver powder layer, lower carbon powder layer, and spacer block. Detailed Implementation
[0027] The present invention will now be further described with reference to the accompanying drawings.
[0028] like Figures 1 to 3 As shown, a pressure-sensitive conductive film includes, from top to bottom, an upper film layer 1, an upper silver powder layer 2, an upper carbon powder layer 3, an isolation layer 4, a lower carbon powder layer 5, a lower silver powder layer 6, and a lower film layer 7. In its free state, the isolation layer 4 isolates the upper carbon powder layer 3 from the lower carbon powder layer 5 or makes the contact area between the upper carbon powder layer 3 and the lower carbon powder layer 5 smaller than the conductive area. When the isolation layer 4 is subjected to pressure, the contact area between the upper carbon powder layer 3 and the lower carbon powder layer 5 becomes larger than the conductive area, thus making the upper silver powder layer 2 and the lower silver powder layer 6 conductive.
[0029] In the unpressurized state, the insulating layer 4 physically separates the upper toner layer 3 and the lower toner layer 5, forming a tiny gap. Due to the insulating properties of air, the resistance between the two layers is close to infinite (greater than 10 MΩ), and the circuit is open. Alternatively, in the unpressurized state, the upper toner layer 3 and the lower toner layer 5 have partial contact, and the contact area is smaller than the conductive area, so that the upper toner layer 3 and the lower toner layer 5 are not conductive. When the contact area between the upper toner layer 3 and the lower toner layer 5 is small, the resulting resistance is large, exceeding its conductive resistance. Therefore, the upper toner layer 3 and the lower toner layer 5 are actually not conductive, and thus the upper silver powder layer 2 and the lower silver powder layer 6 are not conductive. Since it is impossible to completely isolate the upper toner layer 3 from the lower toner layer 5, the contact area between the upper toner layer 3 and the lower toner layer 5 is controlled so that even if there is partial contact, the upper toner layer 3 and the lower toner layer 5 will not conduct, which greatly improves the reliability and accuracy of the detection and avoids the situation where the upper toner layer 3 and the lower toner layer 5 conduct when there is only a small contact due to light pressure or deformation.
[0030] Under pressure, the upper film layer 1 deforms and bends downwards due to the pressure. The pressure overcomes the supporting force of the insulating layer, causing the upper toner layer 3 in the pressure area to directly contact the lower toner layer 5. Since the toner layer itself is conductive, when the upper toner layer 3 and the lower toner layer 5 have a large contact area, the resistance between the upper toner layer 3 and the lower toner layer 5 decreases, thereby achieving conductivity between the upper toner layer 3 and the lower toner layer 5. This also enables conductivity between the upper silver powder layer 2 and the lower silver powder layer 6. In effect, the upper toner layer 3 and the lower toner layer 5 control the resistance between the upper silver powder layer 2 and the lower silver powder layer 6. When the contact area between the upper toner layer 3 and the lower toner layer 5 is small, the resistance between the upper toner layer 3 and the lower toner layer 5 decreases. The resistance between powder layers 5 is relatively high, which is equivalent to the resistance between the upper silver powder layer 2 and the lower silver powder layer 6 being relatively high. Therefore, the upper silver powder layer 2 and the lower silver powder layer 6 cannot conduct. When the contact area between the upper carbon powder layer 3 and the lower carbon powder layer 5 increases, the resistance between the upper carbon powder layer 3 and the lower carbon powder layer 5 decreases. The resistance value at the contact point between the upper carbon powder layer 3 and the lower carbon powder layer 5 drops sharply, approaching 0Ω. The upper carbon powder layer 3 and the lower carbon powder layer 5 are in a conductive state. The upper carbon powder layer 3 and the lower carbon powder layer 5 make the upper silver powder layer 2 and the lower silver powder layer 6 conduct. That is, the contact area between the upper silver powder layer 2 and the lower silver powder layer 6 increases, forming effective conduction, thereby making the pressure-sensitive conductive film in a conductive state.
[0031] No-pressure state: The isolation layer creates a physical gap between the upper film layer 1 and the lower film layer 7. The dielectric (air) in the gap has extremely high resistance, and the circuit is in an open state at this time.
[0032] Under pressure: When an external force is applied to the surface of the upper film layer 1, the pressure point of the upper film layer 1 bends and deforms downward, overcoming the supporting force of the isolation layer, so that the upper carbon powder layer and the lower silver powder layer in this area can directly make physical contact, forming a conductive path, and the circuit is in a conductive state.
[0033] The insulation layer has good insulation properties, a certain degree of hardness, and durability.
[0034] Both the upper film layer 1 and the lower film layer 7 are made of PET film.
[0035] The pressure-sensitive conductive film has a simple and reliable structure, using a double-layer PET film bonding structure with no complex mechanical parts.
[0036] The substrate of the upper film layer 1 is a flexible transparent PET film with a thickness of 0.3~0.4mm. An upper silver powder layer 2 is printed on the side facing the lower layer. Below the upper silver powder layer 2 is a full-surface carbon powder layer. The carbon powder layer has high resistivity and good oxidation resistance, which can effectively protect the upper silver powder layer 2 and ensure the reliability of the contact points under long-term use. In addition, the thickening of the upper film can enhance the overall support of the product, effectively resist deformation caused by external impact or continuous load, and extend the service life of the product.
[0037] The substrate of the lower film layer 7 is a flexible transparent PET film, which is slightly thinner than the upper film layer 1, about 0.1~0.2mm. A lower silver powder layer 6 and a lower carbon powder layer 5 are printed on the side facing the upper film layer 1. The lower silver powder layer 6 has extremely low resistivity and good conductivity. In addition, the lower film is thinner, so it can quickly deform when local pressure is applied, thus transmitting signals.
[0038] The upper film layer 1 is slightly thicker, providing better support and allowing for rapid recovery after deformation. It blocks signals and can resist deformation caused by external impacts or continuous loads, extending the product's service life. The lower film layer 7 is slightly thinner, making it more prone to deformation under pressure, quickly transmitting pressure signals and ensuring the high sensitivity of the conductive film.
[0039] The isolation layer 4 includes several isolation blocks 41, which are disposed on the upper toner layer 3 or the lower toner layer 5, and are used to isolate the upper toner layer 3 and the lower toner layer 5 in a free state. The isolation blocks 41 are evenly distributed on the upper toner layer 3 and the lower toner layer 5. The isolation blocks 41 may also be individually and evenly distributed on the upper toner layer 3 or the lower toner layer 5. The isolation blocks 41 may be printed with insulating ink.
[0040] In this embodiment, isolation blocks 41 are respectively disposed on the upper toner layer 3 and the lower toner layer 5, and are arranged in an array. The isolation blocks 41 of the upper toner layer 3 and the isolation blocks 41 of the lower toner layer 5 are staggered. The isolation blocks 41 are used to separate the silver powder layers on the upper and lower films under no-pressure conditions to prevent the circuit from turning on by itself.
[0041] To control the sensing weight, i.e., to control the conduction pressure, the isolation layer 4 also includes a plurality of heightening blocks 42, which are disposed on the upper toner layer 3 and / or the toner layer 5. The heightening blocks 42 are evenly distributed on the upper toner layer 3 and the lower toner layer 5. The heightening blocks 42 can also be individually and evenly distributed on the upper toner layer 3 or the lower toner layer 5. The heightening blocks 42 can be printed with insulating ink. In this embodiment, the heightening blocks 42 are respectively disposed on the upper toner layer 3 and the lower toner layer 5, and are evenly arranged in an array. The heightening blocks 42 of the upper toner layer 3 and the heightening blocks 42 of the lower toner layer 5 are staggered. The heightening blocks 42 are used to adjust the sensing weight. If it is necessary to increase the sensing weight, the height of the heightening blocks 42 is increased accordingly; if it is necessary to decrease the sensing weight, the height of the heightening blocks 42 is decreased accordingly.
[0042] High precision and sensitivity, dense trigger points, fast response to pressure changes, and pressure can be adjusted according to actual product needs (50~5000g). If a low sensing pressure is required, the height of the riser block 42 between the upper and lower membranes can be reduced, and the number of riser blocks 42 can be reduced. If a high sensing pressure is required, the height of the riser block 42 between the upper and lower membranes can be increased, and the number of riser blocks 42 can be reduced.
[0043] The pressure-sensitive conductive film is easy to integrate, has a thin and lightweight structure, is flexible and can be bent within a certain range, and has self-adhesive backing, making it easy to bond with various materials. Specifically, it also includes an adhesive backing layer 8, which is disposed below the lower film layer 7.
[0044] The upper silver powder layer 2 is provided with a plurality of first conductive lines 21, a plurality of second conductive lines 22, a first lead 23, and a second lead 24. The first conductive lines 21 and second conductive lines 22 are arranged in parallel and staggered order. Each first conductive line 21 is connected to a first lead 23, and each second conductive line 22 is connected to a second lead 24. The lower silver powder layer 6 is provided with a plurality of third conductive lines 61, a plurality of fourth conductive lines 62, a third lead 63, and a fourth lead 64. The third conductive lines 61 and fourth conductive lines 62 are arranged in parallel and staggered order. Each third conductive line 61 is connected to a third lead 63, and each fourth conductive line 62 is connected to a fourth lead 64. Further, the first conductive lines 21 and second conductive lines 22 are arranged intersecting with the third conductive lines 61 and fourth conductive lines 62. Preferably, the first conductive lines 21 and second conductive lines 22 are arranged perpendicular to the third conductive lines 61 and fourth conductive lines 62. The electrodes of the upper and lower layers intersect at 90 degrees, forming a grid-like induction structure. The intersection points form capacitive coupling nodes, ensuring stable signal conduction. In addition, the orthogonal arrangement design eliminates the need for precise alignment, providing the advantage of convenient assembly.
[0045] Pressure membrane parameters:
[0046] Finished product dimensions: 25×25cm;
[0047] Sensing area size: 22×22cm;
[0048] Thickness: ≤0.65mm;
[0049] Approximate weight: 50~5000g (adjustable);
[0050] Durability: >1 million cycles;
[0051] Initial resistance: >10MΩ;
[0052] Operating voltage: 0~12V;
[0053] Operating current: 0~50mA;
[0054] Response time: <1ms;
[0055] Response time: <15ms;
[0056] Operating temperature: -20~60℃.
[0057] The technical principles of this utility model have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this utility model without inventive effort, and these embodiments will all fall within the protection scope of the claims of this utility model.
Claims
1. A pressure-sensitive conductive film, characterized in that, The structure includes, from top to bottom, an upper film layer (1), an upper silver powder layer (2), an upper toner layer (3), an isolation layer (4), a lower toner layer (5), a lower silver powder layer (6), and a lower film layer (7). In a free state, the isolation layer (4) isolates the upper toner layer (3) from the lower toner layer (5) or makes the contact area between the upper toner layer (3) and the lower toner layer (5) smaller than the conductive area. When the isolation layer (4) is subjected to pressure, the contact area between the upper toner layer (3) and the lower toner layer (5) makes the upper silver powder layer (2) and the lower silver powder layer (6) conductive when the contact area between the upper toner layer (3) and the lower toner layer (5) is greater than the conductive area.
2. The pressure-sensitive conductive membrane according to claim 1, characterized in that, The upper silver powder layer (2) is provided with a plurality of first conductors (21), a plurality of second conductors (22), a first lead (23) and a second lead (24). The first conductors (21) and the second conductors (22) are arranged in parallel and interleaved in sequence. The first conductors (21) are all connected to the first lead (23), and the second conductors (22) are all connected to the second lead (24). The lower silver powder layer (6) is provided with a plurality of third conductors (61), a plurality of fourth conductors (62), a third lead (63) and a fourth lead (64). The third conductors (61) and the fourth conductors (62) are arranged in parallel and interleaved in sequence. The third conductors (61) are all connected to the third lead (63), and the fourth conductors (62) are all connected to the fourth lead (64).
3. The pressure-sensitive conductive membrane according to claim 2, characterized in that, The first conductor (21) and the second conductor (22) are both arranged to cross the third conductor (61) and the fourth conductor (62).
4. The pressure-sensitive conductive membrane according to claim 3, characterized in that, The first conductor (21) and the second conductor (22) are both arranged perpendicularly to the third conductor (61) and the fourth conductor (62).
5. The pressure-sensitive conductive membrane according to claim 1, characterized in that, The isolation layer (4) includes a plurality of isolation blocks (41), which are disposed on the upper toner layer (3) and / or the lower toner layer (5) for isolating the upper toner layer (3) and the lower toner layer (5) in a free state.
6. The pressure-sensitive conductive membrane according to claim 5, characterized in that, The isolation layer (4) also includes a plurality of heightening blocks (42), which are disposed on the upper toner layer (3) and / or the lower toner layer (5).
7. A pressure-sensitive conductive membrane according to claim 6, characterized in that, The isolation block (41) and the heightening block (42) are arranged in an array.
8. A pressure-sensitive conductive membrane according to any one of claims 1 to 7, characterized in that, The thickness of the upper film layer (1) is greater than the thickness of the lower film layer (7).
9. A pressure-sensitive conductive membrane according to claim 8, characterized in that, The thickness of the upper film layer (1) is 0.3~0.4mm, and the thickness of the lower film layer (7) is 0.1~0.2mm.
10. A pressure-sensitive conductive membrane according to any one of claims 1 to 7, characterized in that, It also includes an adhesive backing layer (8) disposed below the lower film layer (7).