Flexible circuit board and electronic equipment

Abstract

The utility model discloses a flexible circuit board and an electronic device, the flexible circuit board comprises two conductive layers and a polyarylester fiber layer, the polyarylester fiber layer is arranged between the two conductive layers, and one conductive layer, the polyarylester fiber layer and the other conductive layer are sequentially laminated together along a first direction. According to the flexible circuit board provided by the utility model, the polyarylate fiber layer is arranged between the two conductive layers, so that the bending tensile strength of the flexible circuit board is greatly enhanced.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, in particular to a flexible circuit board and electronic equipment. Background Art

[0002] Flexible Printed Circuit (FPC) is a highly reliable and extremely flexible printed circuit board made of polyimide or polyester film as a substrate. With the birth and development of flexible circuit boards, their application scenarios are becoming more and more extensive. With the innovation of electronic products, FPC products have thinner and more sophisticated circuits. Recently, the market has proposed the idea of ​​applying flexible circuit boards to wearable devices. As daily wear, there are higher requirements for the bending and tensile strength of the product, which cannot be achieved by traditional flexible circuit boards.

[0003] The above contents are only used to assist in understanding the technical solution of the present utility model and do not constitute an admission that the above contents are prior art. Utility Model Content

[0004] The main purpose of the utility model is to provide a flexible circuit board and an electronic device, aiming to solve the above problems.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a flexible circuit board, which includes two conductive layers and a polyarylate fiber layer, wherein the polyarylate fiber layer is arranged between the two conductive layers, wherein one conductive layer, the polyarylate fiber layer, and another conductive layer are stacked together in sequence along a first direction.

[0006] Preferably, in the flexible circuit board, the polyarylate fiber layer is bonded to the two conductive layers by adhesive.

[0007] Preferably, in the flexible circuit board, the polyarylate fiber layer has a first surface and a second surface respectively abutting against one of the conductive layers and the other conductive layer, a first bonding adhesive layer is provided between the first surface and one of the conductive layers, and a second bonding adhesive layer is provided between the second surface and the other conductive layer.

[0008] In order to achieve the above object, the utility model provides a flexible circuit board, which comprises a plurality of conductive layers stacked in sequence along a first direction, wherein a polyarylate fiber layer is disposed between two adjacent conductive layers of at least one of the plurality of conductive layers.

[0009] Preferably, in the flexible circuit board, the multi-layer conductive layer comprises a first conductive layer, a second conductive layer, a third conductive layer, and a fourth conductive layer arranged in sequence along a first direction;

[0010] The polyarylate fiber layer is provided at least one between the first conductive layer and the second conductive layer, between the second conductive layer and the third conductive layer, and between the third conductive layer and the fourth conductive layer.

[0011] Preferably, in the flexible circuit board, two adjacent conductive layers provided with the polyarylate fiber layer are respectively fixed to the polyarylate fiber layer by bonding glue.

[0012] Preferably, the flexible circuit board includes a first conductive layer, a second conductive layer, a third conductive layer, and a fourth conductive layer arranged in sequence in a first direction, wherein a first polyarylate fiber layer is provided between the first conductive layer and the second conductive layer, a second polyarylate fiber layer is provided between the second conductive layer and the third conductive layer, and a third polyarylate fiber layer is provided between the third conductive layer and the fourth conductive layer.

[0013] Preferably, in the flexible circuit board, the first conductive layer, the first polyarylate fiber layer, the second conductive layer, the second polyarylate fiber layer, the third conductive layer, the third polyarylate fiber layer and the fourth conductive layer are stacked and fixed together.

[0014] Preferably, in the flexible circuit board, the first polyarylate fiber layer, the second conductive layer, the second polyarylate fiber layer, the third conductive layer, and the third polyarylate fiber layer are stacked together to form a first stack;

[0015] The first conductive layer, the first laminate, and the fourth conductive layer are laminated together to form a second laminate.

[0016] In order to achieve the above object, the utility model also provides an electronic device, which includes the above-mentioned flexible circuit board.

[0017] The utility model has at least the following beneficial effects:

[0018] The flexible circuit board provided by the utility model has a polyarylate fiber layer arranged between two conductive layers, thereby greatly enhancing the bending and tensile strength of the flexible circuit board.

[0019] Furthermore, polyimide is usually used between two copper materials of a conventional flexible circuit board, that is, the flexible circuit board is composed of copper material and polyimide, and its tensile strength is usually 280MPa; however, the present invention arranges a polyarylate fiber layer between two conductive layers, so that the tensile strength of the flexible circuit board obtained can reach 513MPa, which is much greater than that of the conventional flexible circuit board;

[0020] Furthermore, there is only bonding glue between the two copper layers of the traditional flexible circuit board, and the bending and tensile strength effect is poor. However, a polyarylate fiber layer is added between the conductive layers of the utility model, which greatly enhances the bending and tensile strength of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of an embodiment of the flexible circuit board provided by the utility model.

[0022] Label name Label name 100 Flexible circuit board 4 Covering film glue 1 Conductive layer 5 Graphic copper plating 11 First conductive layer 6 Bonding glue 12 Second conductive layer 61 First bonding glue 61 13 The third conductive layer 62 Second bonding glue 62 14 Fourth conductive layer 63 The third bonding glue 63 2 Polyarylate fiber layer 7 Copper PI 3 Covering film PI

[0023] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0024] In the embodiments of the present invention, the term "and / or" describes the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0025] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0026] The term "plurality" in the embodiments of the present invention refers to two or more than two, and other quantifiers are similar thereto.

[0027] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0028] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the embodiments of the utility model will be described in detail below in conjunction with the accompanying drawings. However, it can be understood by those skilled in the art that in the embodiments of the utility model, many technical details are proposed in order to enable readers to better understand the utility model. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed for protection of the utility model can also be implemented. The division of the following embodiments is for the convenience of description and should not constitute any limitation on the specific implementation of the utility model. The various embodiments can be combined and referenced with each other under the premise of no contradiction.

[0029] The utility model provides a flexible circuit board, such as Figure 1 As shown, the flexible circuit board 100 includes two conductive layers 1 and a polyarylate fiber layer 2, wherein the polyarylate fiber layer 2 is disposed between the two conductive layers 1, wherein one conductive layer 1, the polyarylate fiber layer 2, and another conductive layer 1 are sequentially stacked together along a first direction.

[0030] With the innovation of electronic products, FPC products have thinner and more sophisticated lines. Recently, the market has proposed the idea of ​​using flexible circuit boards in wearable devices. As daily wear, the bending and tensile strength of the product have higher requirements, which cannot be achieved by traditional flexible circuit boards.

[0031] The utility model arranges the polyarylate fiber layer 2 between the two conductive layers 1, thereby greatly enhancing the bending tensile strength of the flexible circuit board 100.

[0032] Furthermore, polyimide is usually used between two copper materials of the conventional flexible circuit board 100, that is, the flexible circuit board 100 is composed of copper material and polyimide, and its tensile strength is usually 280 MPa; however, the present invention arranges a polyarylate fiber layer 2 between the two conductive layers 1, so that the tensile strength of the flexible circuit board 100 obtained can reach at least 513 MPa, which is much greater than the conventional flexible circuit board 100;

[0033] Furthermore, the conventional flexible circuit board 100 has only a bonding glue 6 between the two copper layers, and the bending tensile strength effect is poor, while the utility model adds a polyarylate fiber layer 2 between the conductive layers 1, which greatly enhances the bending tensile strength of the product.

[0034] The polyarylate fiber layer 2 is disposed on the two conductive layers 1 through a bonding adhesive 6. For example, the polyarylate fiber layer 2 may be disposed between the two conductive layers 1 after the bonding adhesive 6 is coated on both sides thereof; more specifically, the polyarylate fiber layer 2 has a first surface and a second surface respectively abutting against one conductive layer 1 and the other conductive layer 1, a first bonding adhesive 61 layer is disposed between the first surface and one conductive layer 1, and a second bonding adhesive 62 layer is disposed between the second surface and the other conductive layer 1. In other embodiments, the polyarylate fiber layer 2 may also be pressed between the two conductive layers 1.

[0035] The utility model also provides a flexible circuit board 100, which includes a plurality of conductive layers 1 stacked in sequence along a first direction, wherein a polyarylate fiber layer 2 is provided between at least two adjacent conductive layers 1 of the plurality of conductive layers 1. The plurality of conductive layers 1 may be two layers, three layers, four layers, etc., which are not specifically limited here.

[0036] Taking the number of the multilayer conductive layer 1 as four layers as an example, the multilayer conductive layer 1 includes a first conductive layer 1, a second conductive layer 1, a third conductive layer 1, and a fourth conductive layer 1 arranged in sequence along a first direction; the polyarylate fiber layer 2 is provided in at least one of the first conductive layer 1 and the second conductive layer 1, between the second conductive layer 1 and the third conductive layer 1, and between the third conductive layer 1 and the fourth conductive layer 1.

[0037] The two adjacent conductive layers 1 provided with the polyarylate fiber layer 2 are fixed to the polyarylate fiber layer 2 respectively by the bonding glue 6. For example, the polyarylate fiber layer 2 is provided between the first conductive layer 1 and the second conductive layer 1, and the polyarylate fiber layer 2 is fixed to the first conductive layer 1 and the second conductive layer 1 respectively by the bonding glue 6. Taking the case where the polyarylate fiber layer 2 is provided between two adjacent conductive layers 1 of one of the multi-layer conductive layers 1, and the number of layers of the multi-layer conductive layer 1 is four as an example, the flexible circuit board 100 includes a covering film PI3, a covering film glue 4, a pattern copper plating 5, a first conductive layer 11, a copper material PI7, a bonding glue 6, a polyarylate fiber layer 2, a bonding glue 6, a second conductive layer 12, a copper material PI7, a third conductive layer 13, a bonding glue 6, a copper material PI7, a fourth conductive layer 14, a pattern copper plating 5, a covering film glue 4, and a covering film PI3 in sequence along the first direction.

[0038] It should be noted that the PI mentioned in the present invention is polyimide (abbreviated as PI).

[0039] More specifically, the flexible circuit board 100 includes a first conductive layer 1, a second conductive layer 1, a third conductive layer 1, and a fourth conductive layer 1 arranged in sequence in a first direction, wherein a first polyarylate fiber layer is provided between the first conductive layer 1 and the second conductive layer 1, a second polyarylate fiber layer is provided between the second conductive layer 1 and the third conductive layer 1, and a third polyarylate fiber layer is provided between the third conductive layer 1 and the fourth conductive layer 1. For example, the flexible circuit board 100 includes a covering film PI3, a covering film glue 4, a pattern copper plating 5, a first conductive layer 11, a polyarylate fiber layer 2, a bonding glue 6, a second conductive layer 12, a polyarylate fiber layer 2, a third conductive layer 13, a bonding glue 6, a polyarylate fiber layer 2, a fourth conductive layer 14, a pattern copper plating 5, a covering film glue 4, and a covering film PI3 in sequence along the first direction.

[0040] It should be noted that, taking the flexible circuit board 100 including a first conductive layer 1, a second conductive layer 1, a third conductive layer 1, and a fourth conductive layer 1 arranged in sequence in a first direction, wherein a first polyarylate fiber layer is provided between the first conductive layer 1 and the second conductive layer 1, a second polyarylate fiber layer is provided between the second conductive layer 1 and the third conductive layer 1, and a third polyarylate fiber layer is provided between the third conductive layer 1 and the fourth conductive layer 1 as an example, the polyarylate fiber layer 2 may be fixed by a single lamination method or by a double lamination method. The single lamination method and the double lamination method will be described in detail below.

[0041] For example, the flexible circuit board 100 includes the first conductive layer 1, the first polyarylate fiber layer, the second conductive layer 1, the second polyarylate fiber layer, the third conductive layer 1, the third polyarylate fiber layer and the fourth conductive layer 1 arranged in the first direction. The first conductive layer 1, the first polyarylate fiber layer, the second conductive layer 1, the second polyarylate fiber layer, the third conductive layer 1, the third polyarylate fiber layer and the fourth conductive layer 1 can be laminated and fixed together. Alternatively, the first polyarylate fiber layer, the second conductive layer 1, the second polyarylate fiber layer, the third conductive layer 1 and the third polyarylate fiber layer can be laminated together to form a first laminate; the first conductive layer 1, the first laminate and the fourth conductive layer 1 can be laminated together to form a second laminate, so that the first conductive layer 1, the first polyarylate fiber layer, the second conductive layer 1, the second polyarylate fiber layer, the third conductive layer 1, the third polyarylate fiber layer and the fourth conductive layer 1 are fixed by laminating twice.

[0042] The conductive layer 1 may be, but is not limited to, a copper layer.

[0043] Example 1: One-time stacking

[0044] Taking the flexible circuit board 100 including the covering film PI3, the covering film glue 4, the pattern copper plating 5, the first conductive layer 11, the copper material PI7, the first bonding glue 61, the polyarylate fiber layer 2, the second bonding glue 62, the second conductive layer 12, the copper material PI7, the third conductive layer 13, the third bonding glue 63, the copper material PI7, the fourth conductive layer 14, the pattern copper plating 5, the covering film glue 4, and the covering film PI3 in sequence along the first direction as an example, the processing of the flexible circuit board 100 includes:

[0045] S1, laser inner hole and glue removal;

[0046] S2, dark shadow, AOI;

[0047] S3, pre-treatment and dry film application;

[0048] S4, exposure, development, copper plating, and film removal;

[0049] S5, pre-treatment and dry film application;

[0050] S6, exposure, development and etching;

[0051] S7, pre-processing and stacking;

[0052] S8, pressing and baking;

[0053] S9, laser outer layer through blind hole;

[0054] S10, pre-processing, black shadow;

[0055] S11, pre-treatment and dry film application;

[0056] S12, exposure, development, copper plating, and film removal;

[0057] S13, pre-treatment and dry film application;

[0058] S14, exposure, development, and etching;

[0059] S15, laminating cover film;

[0060] S16, pressing and baking plate;

[0061] S17, front and back ink;

[0062] S18, surface treatment

[0063] S19, text inkjet;

[0064] S20, shape forming;

[0065] S21, electrical measurement;

[0066] S22, FQC, OQC packaging and shipment.

[0067] Among them, in S7, the first conductive layer 11, the copper material PI7, the first bonding adhesive 61, the polyarylate fiber layer 2, the second bonding adhesive 62, the second conductive layer 12, the copper material PI7, the third conductive layer 13, the third bonding adhesive 63, the copper material PI7, and the fourth conductive layer 14 are stacked together.

[0068] Example 2: Double stacking

[0069] Taking the flexible circuit board 100 including the covering film PI3, the covering film glue 4, the pattern copper plating 5, the first conductive layer 11, the copper material PI7, the first bonding glue 61, the polyarylate fiber layer 2, the second bonding glue 62, the second conductive layer 12, the copper material PI7, the third conductive layer 13, the third bonding glue 63, the copper material PI7, the fourth conductive layer 14, the pattern copper plating 5, the covering film glue 4, and the covering film PI3 in sequence along the first direction as an example, the processing of the flexible circuit board 100 includes:

[0070] S1, laser inner hole and glue removal;

[0071] S2, dark shadow, AOI;

[0072] S3, pre-treatment and dry film application;

[0073] S4, exposure, development, copper plating, and film removal;

[0074] S5, pre-treatment and dry film application;

[0075] S6, exposure, development and etching;

[0076] S7, pre-processing and stacking;

[0077] S8, pre-processing and stacking;

[0078] S9, pressing and baking;

[0079] S10, laser-cut outer layer through blind holes;

[0080] S11, pre-processing, black shadow;

[0081] S12, pre-treatment and dry film application;

[0082] S13, exposure, development, copper plating, and film removal;

[0083] S14, pre-treatment and dry film application;

[0084] S15, exposure, development, and etching;

[0085] S16, laminating cover film;

[0086] S17, pressing and baking plate;

[0087] S18, front and back ink;

[0088] S19, surface treatment

[0089] S20, text inkjet;

[0090] S21, shape forming;

[0091] S22, electrical measurement;

[0092] S23, FQC, OQC packaging and shipment.

[0093] Therein, two laminations are performed, namely S7 and S8. In S7, the polyarylate fiber layer 2, the second bonding adhesive 62, the second conductive layer 12, the copper material PI7, and the third conductive layer 13 are laminated together to form a first laminate.

[0094] In S8 , the first conductive layer 11 + copper material PI7 + first bonding adhesive 61 , the first laminated board after lamination, and the third bonding adhesive 63 + copper material PI7 + fourth conductive layer 14 are laminated to form a second laminated board.

[0095] After the polyarylate fiber layer 2 and the inner double-sided conductive layer 1 (the second conductive layer 12 and the third conductive layer 13) are laminated twice, the outer polyarylate fiber layer 2 can be pre-treated and cleaned again to enhance the bonding strength of the product after lamination.

[0096] The utility model provides an electronic device, which includes the above-mentioned flexible circuit board 100. An embodiment of the electronic device includes an embodiment of the above-mentioned flexible circuit board 100, and the beneficial effects of the above-mentioned flexible circuit board 100 can be applied to the electronic device.

[0097] Obviously, the above described embodiments are only a part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, ordinary technicians in this field can make other different forms of changes or modifications without creative work, which should fall within the scope of protection of the utility model.

Claims

1. A flexible circuit board, characterized in that: It comprises two conductive layers and a polyarylate fiber layer, wherein the polyarylate fiber layer is arranged between the two conductive layers, wherein one conductive layer, the polyarylate fiber layer and the other conductive layer are sequentially stacked together along a first direction.

2. The flexible circuit board according to claim 1, characterized in that: The polyarylate fiber layer is arranged on the two conductive layers by bonding adhesive.

3. The flexible circuit board according to claim 2, characterized in that: The polyarylate fiber layer has a first surface and a second surface respectively abutting against one of the conductive layers and the other conductive layer, a first bonding adhesive layer is provided between the first surface and one of the conductive layers, and a second bonding adhesive layer is provided between the second surface and the other conductive layer.

4. A flexible circuit board, characterized in that: The invention comprises a plurality of conductive layers stacked in sequence along a first direction, wherein a polyarylate fiber layer is arranged between two adjacent conductive layers of at least one of the plurality of conductive layers.

5. The flexible circuit board according to claim 4, characterized in that: The multi-layer conductive layer includes a first conductive layer, a second conductive layer, a third conductive layer, and a fourth conductive layer arranged in sequence along a first direction; The polyarylate fiber layer is provided at least one between the first conductive layer and the second conductive layer, between the second conductive layer and the third conductive layer, and between the third conductive layer and the fourth conductive layer.

6. The flexible circuit board according to claim 5, characterized in that: Two adjacent conductive layers provided with the polyarylate fiber layer are respectively fixed to the polyarylate fiber layer by bonding glue.

7. The flexible circuit board according to claim 5, characterized in that: The flexible circuit board includes a first conductive layer, a second conductive layer, a third conductive layer, and a fourth conductive layer arranged in sequence in a first direction, wherein a first polyarylate fiber layer is provided between the first conductive layer and the second conductive layer, a second polyarylate fiber layer is provided between the second conductive layer and the third conductive layer, and a third polyarylate fiber layer is provided between the third conductive layer and the fourth conductive layer.

8. The flexible circuit board according to claim 7, characterized in that: The first conductive layer, the first polyarylate fiber layer, the second conductive layer, the second polyarylate fiber layer, the third conductive layer, the third polyarylate fiber layer and the fourth conductive layer are stacked and fixed together.

9. The flexible circuit board according to claim 7, characterized in that: The first polyarylate fiber layer, the second conductive layer, the second polyarylate fiber layer, the third conductive layer, and the third polyarylate fiber layer are stacked together to form a first stack; The first conductive layer, the first laminate, and the fourth conductive layer are laminated together to form a second laminate.

10. An electronic device, characterized in that: Comprising the flexible circuit board as described in any one of claims 1 to 9.

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