Circuit board

Abstract

The invention discloses a circuit board. The invention provides a circuit board which comprises a main body board and a protective layer, the main body board is provided with a bending section and two flat sections connected to the two ends of the bending section, and the main body board can be bent through the bending section; the protective layer comprises a first protective layer and a second protective layer, and the first protective layer and the second protective layer are respectively positioned on two opposite side surfaces of the main body plate; wherein a plurality of first grooves are formed in the bending section of the first protection layer, notches of the first grooves face the side, away from the main body plate, of the first protection layer, a plurality of second grooves are formed in the bending section of the second protection layer, and notches of the second grooves face the side, away from the main body plate, of the second protection layer. And the first grooves and the second grooves are arranged in a one-to-one correspondence manner in the thickness direction of the main body plate. The first groove and the second groove provide extrusion and stretching spaces for the circuit board, the trend that internal materials of the first protection layer and the second protection layer recover to a flat state during bending is relieved, the rebound force of the circuit board is reduced, and the reliability is higher.

Description

Technical Field

[0001] The present application relates to the technical field of display panels, and in particular to a circuit board. Background Art

[0002] With the continuous development of display technology, the display effects of various display panels are gradually improving. For example, organic light emitting diode (OLED) display panels and display panels using mini light emitting diode (MiniLight Emitting Diode, Mini-LED) devices or microlight emitting diode (MicroLight Emitting Diode, Micro-LED) devices have the advantages of high image quality, power saving, thin body and wide range of applications. They are widely used in various consumer electronic products such as mobile phones, televisions, personal digital assistants, digital cameras, laptops, desktop computers, etc., and have become the mainstream in display devices.

[0003] However, the performance of circuit boards in current display products needs to be improved. Summary of the invention

[0004] The main purpose of this application is to provide a circuit board, aiming to solve the above-mentioned technical problems existing in the prior art.

[0005] In order to solve the above-mentioned problems, the present application provides a circuit board, which includes a main body plate and a protective layer, the main body plate has a bending section and two flat sections connected to the two ends of the bending section, and the main body plate can be bent through the bending section; the protective layer includes a first protective layer and a second protective layer, and the first protective layer and the second protective layer are respectively located on the two opposite sides of the main body plate; wherein, the first protective layer is formed with a plurality of first grooves in the bending section, and the groove openings of the first grooves are toward the side of the first protective layer away from the main body plate, and the second protective layer is formed with a plurality of second grooves in the bending section, and the groove openings of the second grooves are toward the side of the second protective layer away from the main body plate, and the first grooves and the second grooves are arranged one by one in the thickness direction of the main body plate.

[0006] In some embodiments, an orthographic projection of the first groove on the main body plate coincides with an orthographic projection of the second groove on the main body plate.

[0007] In some embodiments, a first protrusion is formed between two adjacent first grooves, and a second protrusion is formed between two adjacent second grooves, and the first protrusion and the second protrusion are arranged one by one in the thickness direction;

[0008] Preferably, the orthographic projection of the first protrusion on the main body plate coincides with the orthographic projection of the second protrusion on the main body plate.

[0009] In some embodiments, the radial dimension of the first groove gradually decreases in a direction from the notch of the first groove to the bottom of the first groove;

[0010] and / or, the radial dimension of the second groove gradually decreases in a direction from the notch of the second groove to the bottom of the second groove;

[0011] Preferably, the cross-sections of the first groove and the second groove are triangular;

[0012] Preferably, the cross-sections of the first protrusion and the second protrusion are triangular.

[0013] In some embodiments, the main body plate includes a substrate, a first conductive layer and a second conductive layer, the first conductive layer and the second conductive layer are respectively located on two opposite surfaces of the substrate, the first protective layer is located on a side of the first conductive layer away from the substrate, and the second protective layer is located on a side of the second conductive layer away from the substrate;

[0014] Preferably, the first conductive layer and the second conductive layer are made of copper;

[0015] Preferably, the substrate is made of polyamide.

[0016] In some embodiments, the first conductive layer forms a third groove in the bending section, and the first protective layer is at least partially located in the third groove;

[0017] The second conductive layer forms a fourth groove in the bending section, and the second protective layer is at least partially located in the fourth groove;

[0018] Preferably, the first protrusion is convexly disposed on the bottom wall of the third groove;

[0019] Preferably, the second protrusion is protruding from the bottom wall of the fourth groove.

[0020] In some embodiments, the depth of the first groove is less than the sum of the depth of the third groove and the thickness of the first protective layer in the flat section, and the depth of the second groove is less than the sum of the depth of the fourth groove and the thickness of the second protective layer in the flat section;

[0021] Preferably, the depth of the first groove is smaller than the thickness of the first protective layer in the flat section, and the depth of the second groove is smaller than the thickness of the second protective layer in the flat section.

[0022] In some embodiments, the first protective layer includes a first protective film glue and a first protective film, the first protective film is located on a side of the first conductive layer away from the substrate, the first protective film glue is located between the first conductive layer and the first protective film, and the first protective film glue is used to bond the first conductive layer and the first protective film;

[0023] And / or, the second protective layer includes a second protective film glue and a second protective film, the second protective film is located on a side of the second conductive layer away from the substrate, the second protective film glue is located between the first conductive layer and the second protective film, and the second protective film glue is used to bond the first conductive layer and the second protective film;

[0024] Preferably, the first protective film and the second protective film are made of polyamide;

[0025] Preferably, the first protective film glue is at least partially located in the third groove, and the second protective film glue is at least partially located in the fourth groove.

[0026] In some embodiments, the first protective film and the second protective film have different coefficients of thermal expansion;

[0027] Preferably, one of the first protective film and the second protective film is made of a thermal expansion material, and the other is made of a thermal shrinkage material.

[0028] In some embodiments, when the circuit board is in a bent state, the two flat sections form a bending angle, and the smaller the bending angle, the smaller the radial dimension of the first groove and the second groove facing the bending direction, and the larger the radial dimension of the first groove and the second groove away from the bending direction;

[0029] Preferably, when the bending angle is equal to 0 degrees, two opposite side walls of one of the first groove and the second groove facing the bending direction abut against each other.

[0030] Compared with the prior art, the circuit board of the present application includes a main body plate and a protective layer, the main body plate has a bending section and two flat sections connected to the two ends of the bending section, and the main body plate can be bent through the bending section; the protective layer includes a first protective layer and a second protective layer, and the first protective layer and the second protective layer are respectively located on the two opposite sides of the main body plate; wherein, the first protective layer is formed with a plurality of first grooves in the bending section, and the groove openings of the first grooves are toward the side of the first protective layer away from the main body plate, and the second protective layer is formed with a plurality of second grooves in the bending section, and the groove openings of the second grooves are toward the side of the second protective layer away from the main body plate, and the first grooves and the second grooves are arranged one-to-one in the thickness direction of the main body plate. Through the above-mentioned implementation mode, when the main body plate is bent through the bending section, the first protective layer and the second protective layer are deformed, and the first groove and the second groove can provide space for extrusion and stretching for the first protective layer and the second protective layer. At the same time, the first groove and the second groove correspond one to one in the thickness direction of the main body plate, which can further facilitate the bending of the bending section and alleviate the tendency of the internal materials of the first protective layer and the second protective layer to return to a flat state when bending. As a result, the rebound force that drives the circuit board to return to a flat state when the circuit board is bent is reduced, and the risk of the circuit board rebounding and causing the bending state to be cancelled is reduced, thereby improving the bending performance of the circuit board and enhancing the reliability of the circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. 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 paying creative work.

[0032] Figure 1 is a first structural schematic diagram of a circuit board according to one or more embodiments;

[0033] Figure 2 is a second structural schematic diagram of a circuit board according to one or more embodiments;

[0034] Figure 3 is a third structural schematic diagram of a circuit board according to one or more embodiments;

[0035] Figure 4 is a fourth structural schematic diagram of a circuit board according to one or more embodiments;

[0036] Figure 5 is a fifth structural schematic diagram of a circuit board according to one or more embodiments;

[0037] Figure 6 is a schematic structural diagram of a flat section of a circuit board according to one or more embodiments;

[0038] Figure 7 is a sixth structural schematic diagram of a circuit board according to one or more embodiments;

[0039] Figure 8 is a first structural schematic diagram of a circuit board in a bent state according to one or more embodiments;

[0040] Fig. 9 is a second structural schematic diagram of a circuit board in a bent state according to one or more embodiments.

[0041] Reference numerals: circuit board 1; main board 10; bending section 11; flat section 12; first flat section 121; second flat section 122; substrate 13; first conductive layer 14; third groove 141; first sub-conductive layer 142; second sub-conductive layer 143; second conductive layer 15; fourth groove 151; third sub-conductive layer 152; fourth sub-conductive layer 153; protective layer 20; first protective layer 21; first groove 211; first protrusion 212; first protective film 213; first protective film glue 214; second protective layer 22; second groove 221; second protrusion 222; second protective film 223; third protective film glue 224; thickness direction x1; bending direction x2; bending angle y. DETAILED DESCRIPTION

[0042] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0044] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0045] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0046] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0047] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0048] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0049] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0050] With the continuous development of display technology, the display effects of various display panels are gradually improving. For example, organic light emitting diode (OLED) display panels and display panels using mini light emitting diode (MiniLight Emitting Diode, Mini-LED) devices or microlight emitting diode (MicroLight Emitting Diode, Micro-LED) devices have the advantages of high image quality, power saving, thin body and wide range of applications. They are widely used in various consumer electronic products such as mobile phones, televisions, personal digital assistants, digital cameras, laptops, desktop computers, etc., and have become the mainstream in display devices.

[0051] However, the performance of circuit boards in current display products needs to be improved.

[0052] Please refer to Figure 1 , Figure 1 is a first structural schematic diagram of a circuit board according to one or more embodiments.

[0053] To solve the above problems, the present application provides a circuit board 1, which includes a main body plate 10 and a protective layer 20, wherein the main body plate 10 has a bending section 11 and two flat sections 12 connected to the two ends of the bending section 11, and the main body plate 10 can be bent through the bending section 11; the protective layer 20 includes a first protective layer 21 and a second protective layer 22, and the first protective layer 21 and the second protective layer 22 are respectively located on the two opposite sides of the main body plate 10; wherein the first protective layer 21 is formed with a plurality of first grooves 211 in the bending section 11, and the grooves of the first grooves 211 are toward the side of the first protective layer 21 away from the main body plate 10, and the second protective layer 22 is formed with a plurality of second grooves 221 in the bending section 11, and the grooves of the second grooves 221 are toward the side of the second protective layer 22 away from the main body plate 10, and the first grooves 211 and the second grooves 221 are arranged one by one in the thickness direction x1 of the main body plate 10.

[0054] The circuit board 1 may be a flexible circuit board, and the circuit board 1 may be applied to display devices including but not limited to mobile phones, tablets, laptops, desktops, terminals, interactive displays, digital audio and video devices, IoT devices, etc. Among them, interactive displays may include interactive whiteboards, digital advertising interactive screens, and game interactive displays, etc., and IoT devices may include smart home devices and smart wearable devices, etc.

[0055] The main plate 10 has a bending section 11 and two flat sections 12 connected to the two ends of the bending section 11. The main plate 10 can be bent by the bending section 11. For example, when the main plate 10 is in an unbent state, the two flat sections 12 at the two ends of the bending section 11 can be considered to be in the same plane. When the main plate 10 is bent, the bending section 11 bends, and an angle can be formed between the two flat sections 12. According to the different bending degrees, the angle formed by the two flat sections 12 can also be different. The main plate 10 can provide support for the protective layer 20. The protective layer 20 can be used to protect the main plate 10, and at the same time can reduce the risk of short circuit of the main plate 10 and improve the insulation of the circuit board 1. The first protective layer 21 and the second protective layer 22 are respectively located on the two opposite sides of the main plate 10. For example, the first protective layer 21 is located on one side of the main plate 10, and the second protective layer 22 is located on the other side of the main plate 10 away from the first protective layer 21.

[0056] The first protective layer 21 is formed with a plurality of first grooves 211 at corresponding positions of the bending section 11 of the main plate 10, and the notches of the first grooves 211 are toward the side of the first protective layer 21 away from the main plate 10, and the second protective layer 22 is formed with a plurality of second grooves 221 at corresponding positions of the bending section 11 of the main plate 10. Exemplarily, the first grooves 211 and the second grooves 221 can extend respectively in directions parallel to the surface of the main plate 10, and the extension directions of the first grooves 211 and the second grooves 221 can be parallel to the bending line when the main plate 10 is bent, that is, the extension directions of the first grooves 211 and the second grooves 221 can be parallel to each other, and the main plate 10 can be bent along the extension directions of the first grooves 211 and the second grooves 221. The first groove 211 and the second groove 221 are arranged one by one in the thickness direction x1 of the main plate 10. The corresponding arrangement may refer to that a first groove 211 and a second groove 221 are arranged relative to each other in the thickness direction x1. For example, in the thickness direction x1, there is at least one straight line that can simultaneously pass through the first groove 211 and the second groove 221. In some application scenarios, the first groove 211 and the second groove 221 can also be arranged one by one symmetrically with the main plate 10 as a symmetrical plane. It can be understood that when the circuit board 1 is bent, one of the two opposite surfaces of the circuit board 1 will be subjected to an extrusion force, and the other will be subjected to a stretching force. The first groove 211 and the second groove 221 are arranged correspondingly, which can better provide an extrusion space for one side surface and a stretching space for the corresponding position on the other side. For example, the first groove 211 can provide an extrusion space for one side surface of the circuit board 1, and the second groove 221 can provide a stretching space for the other side surface of the circuit board 1, thereby reducing the rebound force of the internal material of the protective layer 20 during the extrusion and stretching process to drive the circuit board 1 to return to a flat state.

[0057] Through the above-mentioned embodiment, when the main plate 10 is bent through the bending section 11, the first protective layer 21 and the second protective layer 22 are deformed, and the first groove 211 and the second groove 221 can provide the first protective layer 21 and the second protective layer 22 with space for extrusion and stretching. At the same time, the first groove 211 and the second groove 221 correspond one to one in the thickness direction x1 of the main plate 10, which can further facilitate the bending of the bending section 11 and alleviate the tendency of the internal materials of the first protective layer 21 and the second protective layer 22 to return to a flat state during bending. As a result, the rebound force that drives the circuit board 1 to return to a flat state when the circuit board 1 is bent is reduced, and the risk of the circuit board 1 rebounding and causing the bending state to be cancelled is reduced, thereby improving the bending performance of the circuit board 1 and enhancing the reliability of the circuit board 1.

[0058] In some embodiments, the orthographic projection of the first groove 211 on the main plate 10 coincides with the orthographic projection of the second groove 221 on the main plate 10. Thus, when the main plate 10 is bent through the bending section 11, a first groove 211 and a second groove 221 that are arranged correspondingly can coincide with the same bending line at the same time, so that the first groove 211 and the second groove 221 can simultaneously provide compression and stretching space for the bending of the corresponding position of the main plate 10, thereby further alleviating the tendency of the internal materials of the first protective layer 21 and the second protective layer 22 to return to a flat state during bending, and reducing the risk of the circuit board 1 rebounding and canceling the bending state.

[0059] See also Figure 2 , Figure 2 is a second structural schematic diagram of a circuit board according to one or more embodiments.

[0060] In some embodiments, a first protrusion 212 is formed between two adjacent first grooves 211, and a second protrusion 222 is formed between two adjacent second grooves 221, and the first protrusion 212 and the second protrusion 222 are arranged one by one in the thickness direction x1. Exemplarily, the first protrusion 212 can separate the two adjacent first grooves 211, and the second protrusion 222 can separate the two adjacent second grooves 221. Corresponding arrangement can mean that a first protrusion 212 and a second protrusion 222 are arranged oppositely in the thickness direction x1, and exemplarily, in the thickness direction x1, there is at least one straight line that can simultaneously pass through the first protrusion 212 and the second protrusion 222. Preferably, the orthographic projection of the first protrusion 212 on the main plate 10 coincides with the orthographic projection of the second protrusion 222 on the main plate 10. In some application scenarios, the first protrusion 212 and the second protrusion 222 can also be arranged one by one symmetrically with the main plate 10 as the symmetry plane. Therefore, the first groove 211 and the second groove 221 are arranged in one-to-one correspondence, and the first protrusion 212 and the second protrusion 222 are arranged in one-to-one correspondence, so as to further reduce the rebound force that drives the circuit board 1 to return to a flat state when the circuit board 1 is bent.

[0061] In some embodiments, the radial dimension of the first groove 211 gradually decreases from the notch of the first groove 211 to the bottom of the first groove 211; and / or, the radial dimension of the second groove 221 gradually decreases from the notch of the second groove 221 to the bottom of the second groove 221. When the circuit board 1 is in a bent state, the first protective layer 21 and the second protective layer 22 are subjected to greater compression or stretching as they are farther away from the main plate 10 in the thickness direction x1. The radial dimension of the first groove 211 gradually decreases from the notch of the first groove 211 to the bottom of the first groove 211, that is, the radial dimension of the first groove 211 gradually increases from the bottom of the first groove 211 to the notch of the first groove 211. Thus, the first groove 211 can provide a larger compression or stretching space for the portion of the first protective layer 21 subjected to a greater compression or stretching effect. Similarly, the second groove 221 can also provide a larger compression or stretching space for the portion of the second protective layer 22 subjected to a greater compression or stretching effect, further reducing the rebound force that drives the circuit board 1 to return to a flat state when the circuit board is bent, and reducing the risk of the circuit board 1 rebounding and canceling the bent state. Preferably, the cross-sections of the first groove 211 and the second groove 221 are triangular. Preferably, the cross-sections of the first protrusion 212 and the second protrusion 222 are triangular. For example, the plurality of first protrusions 212 and the plurality of second protrusions 222 may form a triangular sawtooth cross-section.

[0062] See also Figure 3-Figure 4 , Figure 3 is a third structural schematic diagram of a circuit board according to one or more embodiments; Figure 4 is a fourth structural schematic diagram of a circuit board according to one or more embodiments.

[0063] In some embodiments, the main board 10 includes a substrate 13, a first conductive layer 14 and a second conductive layer 15, the first conductive layer 14 and the second conductive layer 15 are respectively located on the opposite sides of the substrate 13, the first protective layer 21 is located on the side of the first conductive layer 14 away from the substrate 13, and the second protective layer 22 is located on the side of the second conductive layer 15 away from the substrate 13. The substrate 13 can provide support for the first conductive layer 14 and the second conductive layer 15, and the first conductive layer 14 and the second conductive layer 15 can facilitate the circuit board 1 to conduct electricity. Preferably, the material of the first conductive layer 14 and the second conductive layer 15 is copper; preferably, the material of the substrate 13 is polyamide.

[0064] In some embodiments, the first conductive layer 14 forms a third groove 141 in the bending section 11, and the first protective layer 21 is at least partially located in the third groove 141; the second conductive layer 15 forms a fourth groove 151 in the bending section 11, and the second protective layer 22 is at least partially located in the fourth groove 151. Therefore, when the circuit board 1 is in a bent state, the third groove 141 provides a space for squeezing or stretching the first conductive layer 14, which alleviates the tendency of the material inside the first conductive layer 14 to return to a flat state when bending, reduces the rebound force in the first conductive layer 14 that drives the first conductive layer 14 to return to a flat state when the circuit board 1 is bent, reduces the risk of the circuit board 1 rebounding and causing the bending state to be cancelled, further improves the bending performance of the circuit board 1, and thus enhances the reliability of the circuit board 1. In some embodiments, the first protective layer 21 can be at least partially filled in the third groove 141, thereby providing protection and insulation for the first conductive layer 14, and the third groove 141 can provide sufficient space for the first protective layer 21 to form the first groove 211. Furthermore, the first protective layer 21 is at least partially located in the third groove 141, so that the first protective layer 21 is flat as a whole, wherein the overall flatness can be considered that the highest height of the first protective layer 21 of the bending section 11 protruding from the main plate 10 is the same as the height of the first protective layer 21 of the flat section 12 protruding from the main plate 10. Preferably, the first protrusion 212 is protruding from the bottom wall of the third groove 141, so that the first groove 211 and the first protrusion 212 provide a space for squeezing or stretching the first conductive layer 14 located in the bending section 11. In this way, the risk of interference between the first groove 211 and the first conductive layer 14 causing a decrease in the reliability of the first conductive layer 14 can be reduced, thereby increasing the number of times the first conductive layer 14 can be bent.

[0065] Correspondingly, when the circuit board 1 is in a bent state, the fourth groove 151 provides a space for squeezing or stretching the second conductive layer 15, which alleviates the tendency of the material inside the second conductive layer 15 to return to a flat state when bent, reduces the rebound force in the second conductive layer 15 that drives the second conductive layer 15 to return to a flat state when the circuit board 1 is bent, reduces the risk of the circuit board 1 rebounding and causing the bending state to be cancelled, further improves the bending performance of the circuit board 1, and thus enhances the reliability of the circuit board 1. In some embodiments, the second protective layer 22 can be at least partially filled in the fourth groove 151, thereby providing protection and insulation for the second conductive layer 15, and the fourth groove 151 can provide sufficient space for the second protective layer 22 to form a second groove 221. Further, the second protective layer 22 is at least partially located in the fourth groove 151, which can make the second protective layer 22 flat as a whole, wherein the overall flatness can be considered that the highest height of the second protective layer 22 of the bending section 11 protruding from the main plate 10 is the same as the height of the second protective layer 22 of the flat section 12 protruding from the main plate 10. Preferably, the first protrusion 212 is protruding from the bottom wall of the fourth groove 151, so that the second groove 221 and the first protrusion 212 provide a space for squeezing or stretching the second conductive layer 15 located in the bending section 11. Thus, the risk of interference between the second groove 221 and the second conductive layer 15 causing the reliability of the second conductive layer 15 to decrease can be reduced, thereby increasing the number of times the second conductive layer 15 can be bent.

[0066] In some embodiments, the depth of the first groove 211 is less than the sum of the depth of the third groove 141 and the thickness of the first protective layer 21 in the flat section 12, and the depth of the second groove 221 is less than the sum of the depth of the fourth groove 151 and the thickness of the second protective layer 22 in the flat section 12. As a result, the first groove 211 will not interfere with the first conductive layer 14, thereby improving the flatness of the first conductive layer 14. Correspondingly, the second groove 221 will not interfere with the second conductive layer 15, thereby improving the flatness of the second conductive layer 15, thereby alleviating the risk of the first conductive layer 14 and the second conductive layer 15 interfering with the first groove 211 and the second groove 221 when the circuit board 1 is bent and being damaged, thereby increasing the number of bending times of the circuit board 1. Preferably, the depth of the first groove 211 is less than the thickness of the first protective layer 21 in the flat section 12, and the depth of the second groove 221 is less than the thickness of the second protective layer 22 in the flat section 12, thereby further reducing the risk of the first groove 211 and the second groove 221 interfering with the first conductive layer 14 and the second conductive layer 15.

[0067] See also Figure 5-Figure 6 , Figure 5 is a fifth structural schematic diagram of a circuit board according to one or more embodiments; Figure 6 is a schematic diagram of a flat section of a circuit board according to one or more embodiments.

[0068] In some embodiments, the first protective layer 21 includes a first protective film glue 214 and a first protective film 213, the first protective film 213 is located on the side of the first conductive layer 14 away from the substrate 13, the first protective film glue 214 is located between the first conductive layer 14 and the first protective film 213, and the first protective film glue 214 is used to bond the first conductive layer 14 and the first protective film 213; and / or, the second protective layer 22 includes a second protective film glue 224 and a second protective film 223, the second protective film 223 is located on the side of the second conductive layer 15 away from the substrate 13, the second protective film glue 224 is located between the first conductive layer 14 and the second protective film 223, and the second protective film glue 224 is used to bond the first conductive layer 14 and the second protective film 223. As a result, the first protective film glue 214 reduces the risk of the first protective film 213 being separated from the first conductive layer 14, and the second protective film glue 224 reduces the risk of the second protective film 223 being separated from the second conductive layer 15, thereby improving the reliability of the circuit board 1. Preferably, the material of the first protective film 213 and the second protective film 223 is polyamide. Preferably, the first protective film glue 214 is at least partially located in the third groove 141, and the second protective film glue 224 is at least partially located in the fourth groove 151, thereby improving the bonding effect of the first protective film glue 214 on the first conductive layer 14 and the first protective film 213 and the bonding effect of the second protective film glue 224 on the second conductive layer 15 and the second protective film 223, and at the same time, the overall flatness of the first protective layer 21 and the second protective layer 22 can be improved.

[0069] In some embodiments, the first protective film 213 and the second protective film 223 have different thermal expansion coefficients. Preferably, the material of one of the first protective film 213 and the second protective film 223 is a thermal expansion material, and the material of the other is a heat shrink material. Exemplarily, the first protective film 213 is a thermal expansion material, and the second protective film 223 is a heat shrink material. The thermal expansion material can provide a preset tensile stress for the first protective film 213, and the heat shrink material can provide a preset compressive stress for the second protective film 223. When the circuit board 1 is bent toward the side of the second protective film 223, the tensile stress and the compressive stress are released, thereby reducing the rebound force of the circuit board 1, and further reducing the risk of the circuit board 1 rebounding and causing the bending state to be cancelled. In some application scenarios, the thermal expansion material can be a polyamide with a ratio of 8 ten-thousandths, and the heat shrink material can be a polyamide with a ratio of negative one ten-thousandth.

[0070] See also Figure 7 , Figure 7 is a sixth structural schematic diagram of a circuit board according to one or more embodiments.

[0071] In some embodiments, the first conductive layer 14 may include a first sub-conductive layer 142 and a second sub-conductive layer 143, the first sub-conductive layer 142 is located on one side of the substrate 13, the second sub-conductive layer 143 is located on the side of the first sub-conductive layer 142 of the flat section 12 away from the substrate 13, and the second sub-conductive layer 143 is protruded from the first sub-conductive layer 142 of the flat section 12, thereby cooperating with the first sub-conductive layer 142 to form a third groove 141 in the bending section 11, wherein the first sub-conductive layer 142 and the second sub-conductive layer 143 can be formed in different manufacturing processes, thereby reducing the manufacturing difficulty of the circuit board 1 and reducing the production cost. In some other embodiments, the second conductive layer 15 may include a third sub-conductive layer 152 and a fourth sub-conductive layer 153, wherein the third sub-conductive layer 152 is located on a side of the substrate 13 away from the first sub-conductive layer 142, and the fourth sub-conductive layer 153 is located on a side of the third sub-conductive layer 152 of the flat section 12 away from the substrate 13, and the fourth sub-conductive layer 153 is protruded from the third sub-conductive layer 152 of the flat section 12, thereby cooperating with the third sub-conductive layer 152 to form a fourth groove 151 in the bending section 11, wherein the third sub-conductive layer 152 and the fourth sub-conductive layer 153 can be formed in different manufacturing processes, thereby further reducing the manufacturing difficulty of the circuit board 1 and reducing the production cost.

[0072] See also Figure 8-Figure 9 , Figure 8 is a first structural schematic diagram of a circuit board in a bent state according to one or more embodiments; Fig. 9 is a second structural schematic diagram of a circuit board in a bent state according to one or more embodiments.

[0073] In some embodiments, when the circuit board 1 is in a bent state, the two flat sections 12 form a bending angle y, and the smaller the bending angle y, the smaller the radial dimension of the one of the first groove 211 and the second groove 221 facing the bending direction x2, and the larger the radial dimension of the one of the first groove 211 and the second groove 221 away from the bending direction x2. Preferably, when the bending angle y is equal to 0 degrees, the two opposite side walls of the one of the first groove 211 and the second groove 221 facing the bending direction x2 abut against each other. Exemplarily, the two flat segments 12 are defined as a first flat segment 121 and a second flat segment 122. With the first flat segment 121 as a reference, the bending direction x2 may be the direction in which the second flat segment 122 is bent relative to the second flat segment 122. For example, the second flat segment 122 may be bent toward the first protective layer 21 or toward the second protective layer 22. Taking the bending of the second flat segment 122 toward the first protective layer 21 relative to the first flat segment 121 as an example, the bending angle y may be the angle between the plane where the first flat segment 121 is located and the plane where the second flat segment 122 is located. The smaller the bending angle y is, the greater the degree of bending of the circuit board 1 compared to the flat state. It can be understood that when the bending angle y is smaller, the greater the degree of bending of the circuit board 1 is, the second groove 221 provides a stretching space for the second protective layer 22, the larger the radial dimension of the second groove 221 is, the first groove 211 provides an extrusion space for the first protective layer 21, and the smaller the radial dimension of the first groove 211 is.

[0074] In summary, the present application provides a circuit board 1, which includes a main body plate 10 and a protective layer 20, wherein the main body plate 10 has a bending section 11 and two flat sections 12 connected to the two ends of the bending section 11, and the main body plate 10 can be bent through the bending section 11; the protective layer 20 includes a first protective layer 21 and a second protective layer 22, and the first protective layer 21 and the second protective layer 22 are respectively located on the two opposite sides of the main body plate 10; wherein the first protective layer 21 is formed with a plurality of first grooves 211 in the bending section 11, and the grooves of the first grooves 211 are toward the side of the first protective layer 21 away from the main body plate 10, and the second protective layer 22 is formed with a plurality of second grooves 221 in the bending section 11, and the grooves of the second grooves 221 are toward the side of the second protective layer 22 away from the main body plate 10, and the first grooves 211 and the second grooves 221 are arranged one by one in the thickness direction x1 of the main body plate 10. Through the above-mentioned embodiment, when the main plate 10 is bent by the bending section 11, the first protective layer 21 and the second protective layer 22 are deformed, and the first groove 211 and the second groove 221 can provide the first protective layer 21 and the second protective layer 22 with a space for extrusion and stretching. At the same time, the first groove 211 and the second groove 221 correspond one to one in the thickness direction x1 of the main plate 10, which can further facilitate the bending of the bending section 11, and alleviate the tendency of the internal materials of the first protective layer 21 and the second protective layer 22 to return to a flat state when bending. Thus, the rebound force that drives the circuit board 1 to return to a flat state when the circuit board 1 is bent is reduced, and the risk of the circuit board 1 rebounding and canceling the bending state is reduced, thereby improving the bending performance of the circuit board 1 and enhancing the reliability of the circuit board 1. Compared with other circuit boards, the circuit board 1 provided in the present application has a smaller rebound force and higher reliability.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A circuit board, characterized in that: The circuit board comprises: A main body plate, comprising a bending section and two flat sections connected to both ends of the bending section, wherein the main body plate can be bent by the bending section; A protective layer, comprising a first protective layer and a second protective layer, wherein the first protective layer and the second protective layer are respectively located on two opposite sides of the main plate; Among them, the first protective layer forms a plurality of first grooves in the bending section, and the notches of the first grooves face the side of the first protective layer away from the main plate, and the second protective layer forms a plurality of second grooves in the bending section, and the notches of the second grooves face the side of the second protective layer away from the main plate, and the first grooves and the second grooves are arranged one by one in the thickness direction of the main plate.

2. The circuit board according to claim 1, characterized in that: The orthographic projection of the first groove on the main plate coincides with the orthographic projection of the second groove on the main plate.

3. The circuit board according to claim 1 or 2, characterized in that: A first convex portion is formed between two adjacent first grooves, and a second convex portion is formed between two adjacent second grooves, and the first convex portion and the second convex portion are arranged one-to-one in the thickness direction; Preferably, the orthographic projection of the first protrusion on the main body plate coincides with the orthographic projection of the second protrusion on the main body plate.

4. The circuit board according to claim 3, characterized in that: In a direction from the notch of the first groove to the bottom of the first groove, the radial dimension of the first groove gradually decreases; and / or, the radial dimension of the second groove gradually decreases in a direction from the notch of the second groove to the bottom of the second groove; Preferably, the cross-sections of the first groove and the second groove are triangular; Preferably, the cross-sections of the first protrusion and the second protrusion are triangular.

5. The circuit board according to claim 1, characterized in that: The main body plate comprises a substrate, a first conductive layer and a second conductive layer, wherein the first conductive layer and the second conductive layer are respectively located on two opposite surfaces of the substrate, the first protective layer is located on a side of the first conductive layer away from the substrate, and the second protective layer is located on a side of the second conductive layer away from the substrate; Preferably, the first conductive layer and the second conductive layer are made of copper; Preferably, the substrate is made of polyamide.

6. The circuit board according to claim 5, characterized in that: The first conductive layer forms a third groove in the bending section, and the first protective layer is at least partially located in the third groove; The second conductive layer forms a fourth groove in the bending section, and the second protective layer is at least partially located in the fourth groove; Preferably, the first protrusion is convexly disposed on the bottom wall of the third groove; Preferably, the second protrusion is protruding from the bottom wall of the fourth groove.

7. The circuit board according to claim 1, characterized in that: The depth of the first groove is less than the sum of the depth of the third groove and the thickness of the first protective layer in the flat section, and the depth of the second groove is less than the sum of the depth of the fourth groove and the thickness of the second protective layer in the flat section; Preferably, the depth of the first groove is smaller than the thickness of the first protective layer in the flat section, and the depth of the second groove is smaller than the thickness of the second protective layer in the flat section.

8. The circuit board according to claim 6, characterized in that: The first protective layer includes a first protective film glue and a first protective film, the first protective film is located on a side of the first conductive layer away from the substrate, the first protective film glue is located between the first conductive layer and the first protective film, and the first protective film glue is used to bond the first conductive layer and the first protective film; And / or, the second protective layer includes a second protective film glue and a second protective film, the second protective film is located on a side of the second conductive layer away from the substrate, the second protective film glue is located between the first conductive layer and the second protective film, and the second protective film glue is used to bond the first conductive layer and the second protective film; Preferably, the first protective film and the second protective film are made of polyamide; Preferably, the first protective film glue is at least partially located in the third groove, and the second protective film glue is at least partially located in the fourth groove.

9. The circuit board according to claim 8, characterized in that: The first protective film and the second protective film have different thermal expansion coefficients; Preferably, one of the first protective film and the second protective film is made of a thermal expansion material, and the other is made of a thermal shrinkage material.

10. The circuit board according to claim 1, characterized in that: When the circuit board is in a bent state, the two flat sections form a bending angle, and the smaller the bending angle, the smaller the radial dimension of the one of the first groove and the second groove facing the bending direction, and the larger the radial dimension of the one of the first groove and the second groove away from the bending direction; Preferably, when the bending angle is equal to 0 degrees, two opposite side walls of one of the first groove and the second groove facing the bending direction are in contact with each other.

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