An FPC structure

Abstract

The utility model belongs to the technical field of circuit board, concretely relates to a FPC structure, including base layer, conducting layer and insulating protective layer, conducting layer is connected in the side surface of base layer, and is equipped with golden finger on conducting layer, base layer has at least one edge, one side end of golden finger extends to the edge and sets up, insulating protective layer is connected to the side surface of golden finger far from base layer, and one side end of insulating protective layer extends through the edge and sets up, and the insulating protective layer is equipped with assembly gap between edge, the utility model can reduce the phenomenon that golden finger and base layer appear too big section when bending and cause breakage, and further have the advantage that improve its stability of using.

Description

Technical Field

[0001] This utility model belongs to the field of circuit board technology, and in particular relates to an FPC structure. Background Technology

[0002] In the manufacturing process of display modules, such as LED displays, the interconnection between the display electrode terminals and the FPC (Flexible Printed Circuit board) is involved. Stable and reliable mechanical and electrical connections are usually achieved by applying pressure and heating, collectively known as FPC Bonding.

[0003] However, some existing FPC structures are prone to significant breakage during bending and use, which affects their stability. Utility Model Content

[0004] The purpose of this utility model is to provide an FPC structure that addresses the shortcomings of existing technologies and solves the technical problem that existing technologies are prone to significant breakage.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An FPC structure includes a base layer, a conductive layer, and an insulating protective layer; the conductive layer is connected to a side surface of the base layer; and a gold finger is provided on the conductive layer; the base layer has at least one edge; one side end of the gold finger extends toward the edge; the insulating protective layer is connected to a side surface of the gold finger away from the base layer, and one side end of the insulating protective layer extends through the edge; and an assembly gap is provided between the insulating protective layer and the edge.

[0007] Preferably, the width D of the assembly gap satisfies: 380μm≤D≤450μm.

[0008] Preferably, the insulating protective layer includes a wavy segment and at least two straight segments; the wavy segment and all the straight segments are sequentially arranged to surround each other; and the straight segments extend through the edge; the wavy segment is connected to the conductive layer.

[0009] Preferably, the gold finger includes at least one connecting strip; one side end of the connecting strip extends toward the edge; and the width L of the connecting strip satisfies: A-0.02mm≤L≤A+0.03mm; wherein, A satisfies: 0.08mm≤A≤0.12mm.

[0010] Preferably, the insulating protective layer is made of polyimide or polyester film.

[0011] Preferably, the base layer is provided with a double-layer area and a second single-layer area and a first single-layer area connected to the double-layer area; in the double-layer area, the conductive layer is connected to two opposite side surfaces of the base layer; in the second single-layer area or the first single-layer area, the conductive layer is connected to one side surface of the base layer; and the gold finger is disposed on the second single-layer area or the first single-layer area.

[0012] Preferably, the second single-layer region has an external connection area on the side away from the double-layer region and / or the first single-layer region has an external connection area on the side away from the double-layer region; the gold finger is disposed on the external connection area.

[0013] Preferably, a reinforcing layer is further provided on the base layer; the conductive layer in the first single-layer region and the reinforcing layer are disposed opposite to each other on both sides of the base layer; and / or, the conductive layer in the second single-layer region and the reinforcing layer are disposed opposite to each other on both sides of the base layer.

[0014] Preferably, the reinforcing layer is made of stainless steel, polyimide, or polyethylene terephthalate.

[0015] Preferably, an electromagnetic shielding layer is further provided on the base layer; the electromagnetic shielding layer is connected to the surface of the insulating protective layer away from the gold finger; and the projection of the electromagnetic shielding layer toward the insulating protective layer covers the insulating protective layer.

[0016] The beneficial effects of this utility model are that, by using an insulating protective layer that extends through the edge and covers the outer surface of the gold finger, the gold finger and the base layer are reduced to avoid breakage due to excessive shear surface when bent; thereby ensuring the contact area between the gold finger and the conductive layer and ensuring the number of particles; thus improving the stability of its use. Attached Figure Description

[0017] The following will refer to the appendix. Figures 1-5 This section describes the features, advantages, and technical effects of exemplary embodiments of the present invention.

[0018] Figure 1 This is a front view of the first side of an FPC structure according to an embodiment of the present invention;

[0019] Figure 2 This is a front view of the second side of an FPC structure according to an embodiment of the present invention;

[0020] Figure 3 This is a partially enlarged view of the first side of an FPC structure according to an embodiment of the present invention;

[0021] Figure 4This is a partially enlarged view of the first side of an FPC structure according to an embodiment of the present invention;

[0022] Figure 5 This is a partial structural diagram of an FPC structure according to an embodiment of the present invention.

[0023] In the diagram: 1-Base layer; 11-Reinforcing layer; 12-Electromagnetic shielding layer; 101-Double-layer area; 102-Second single-layer area; 103-First single-layer area; 104-External connection area; 105-Edge; 2-Conductive layer; 21-Gold finger; 211-Connecting strip; 3-Insulating protective layer; 31-Straight section; 32-Wave section; 301-Assembly gap. Detailed Implementation

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is intended to particularly describe embodiments and not to limit the scope of this application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0025] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the embodiment description, "multiple" refers to two or more, unless otherwise specifically defined.

[0026] The term 'embodiment' means that a particular feature, structure, or characteristic described exists in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0027] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or multiple situations existing alone. In addition, the character " / " in this document generally indicates that the related objects before and after are in an "or" relationship.

[0028] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can also refer to a mechanical connection or an electrical connection. They can be directly connected or indirectly connected through an intermediate medium, manifesting as internal communication between two components or an interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0029] The following is in conjunction with the appendix Figures 1-5 The present invention will be described in further detail, but this is not intended to limit the scope of the present invention.

[0030] like Figure 1 and 2 As shown, in one embodiment of this utility model, the FPC structure includes a base layer 1, a conductive layer 2, and an insulating protective layer 3. The conductive layer 2 is connected to the side surface of the base layer 1, and a gold finger 21 is provided on the conductive layer 2. The base layer 1 (the side end face in the circumferential direction) has at least one edge 105. One side end of the gold finger 21 extends toward the edge 105. The insulating protective layer 3 is connected to the side surface of the gold finger 21 away from the base layer 1, and one side end of the insulating protective layer 3 extends through the edge 105. An assembly gap 301 is provided between the insulating protective layer 3 and the edge 105. The base layer 1 is made of polyimide (PI) or polyester (PET) film to achieve a thin and flexible feel.

[0031] The technical solution of this utility model adopts an insulating protective layer that extends through the edge and covers the outer surface of the gold finger, so as to reduce the phenomenon of breakage caused by excessive shear surface when the gold finger and the base layer are bent; thereby ensuring the contact area between the gold finger and the conductive layer and ensuring the number of particles; thus, it is beneficial to improve the stability of its use.

[0032] Specifically, in some implementations, such as Figure 1 and 3 As shown, the width D of the assembly gap 301 satisfies: 380μm≤D≤450μm; it can be selected from 380μm, 3900μm, 400μm, 410μm, 420μm, 425μm, 450μm, etc.; preferably 400μm or 450μm. This structure, through the through portion of the insulating protective layer 3, maintains a suitable distance from the edge 105 of the base layer 1, while ensuring the expansion coefficient of the conductive layer 2 and its gold fingers 21 meets the corresponding specification requirements; it also ensures the stability of use.

[0033] Specifically, in some implementations, such as Figure 1 and 3As shown, the insulating protective layer 3 includes a wavy section 32 and at least two straight sections 31; the wavy section 32 and all the straight sections 31 are sequentially connected and integrated; and the straight sections 31 extend through the edge 105; the wavy section 32 is connected to the conductive layer 2. Wherein, as... Figure 3 As shown, there are three straight sections 31, which are connected in sequence as a whole; the two ends of the wave section 32 are respectively connected to the two adjacent straight sections 31; so as to ensure the particle protection effect in certain places through the wave-shaped structure, thereby improving the stability of use.

[0034] Specifically, in some implementations, such as Figure 3 and 4 As shown, the gold finger 21 includes at least two connecting strips 211; one end of the connecting strip 211 extends toward the edge 105; and the width L of the connecting strip 211 satisfies: A - 0.02mm ≤ L ≤ A + 0.03mm; wherein A satisfies: 0.08mm ≤ A ≤ 0.12mm. This structure, by extending the wavy insulating protective layer 3 outward by 400μm or 450μm, helps to ensure that the center value of the width specification requirement of the connecting strip 211 (PIN) remains unchanged when the coefficient of expansion increases; thus, it helps to ensure the stability of its use.

[0035] Specifically, in some embodiments, the insulating protective layer 3 is made of polyimide (PI) or polyester (PET) film to provide better protection for the conductive layer 2. The conductive layer 2 is a metal-plated layer, preferably electrolytic copper foil or rolled copper foil. After etching, it exhibits fine circuit patterns. Electrolytic copper foil has a darker appearance, while rolled copper foil has a higher gloss; thus ensuring the conductivity stability and smoothness of the circuit. Of course, for those skilled in the art, the gold finger 21 and the metal-plated layer are directly metallurgically bonded through the process of "copper foil patterning → surface treatment (gold plating)," without the need for additional welding or mechanical connection.

[0036] Specifically, in some implementations, such as Figure 1 and 2 As shown, the base layer 1 has a double-layer region 101 and a second single-layer region 102 and a first single-layer region 103 connected to the double-layer region 101; in the double-layer region 101, a conductive layer 2 is connected to two opposite side surfaces of the base layer 1; in the second single-layer region 102 or the first single-layer region 103, the conductive layer 2 is connected to one side surface of the base layer 1; and a gold finger 21 is disposed on the second single-layer region 102 or the first single-layer region 103. In some embodiments, the base layer 1 has a first surface (front) and a second surface (back) disposed opposite to each other; the first surface has the second single-layer region 102 and the double-layer region 101; the second surface has the double-layer region 101 and the first single-layer region 103. Further, in some embodiments, such as... Figure 4As shown, an external connection area 104 is provided on the side of the second single-layer region 102 away from the double-layer region 101 and / or on the side of the first single-layer region 103 away from the double-layer region 101; the gold finger 21 (middle connecting strip 211) is provided on the external connection area 104. That is to say, this structure provides an insulating protective layer 3 extending through the edge 105 of the second single-layer region 102 or the first single-layer region 103 where the gold finger 21 is located, so as to achieve the protection of the gold finger at different positions, thereby reducing the phenomenon of breakage caused by excessive shear surface when the gold finger and the base layer are bent; and thus ensuring the contact area between the gold finger and the conductive layer to ensure the number of particles.

[0037] Specifically, in some implementations, such as Figure 1 As shown, a reinforcing layer 11 is also provided on the base layer 1; the conductive layer 2 in the first single-layer region 103 and the reinforcing layer 11 are disposed opposite to each other on both sides of the base layer 1; and / or, the conductive layer 2 in the second single-layer region 102 and the reinforcing layer 11 are disposed opposite to each other on both sides of the base layer 1. In some embodiments, the conductive layer 2 in the first single-layer region 103 and the reinforcing layer 11 are disposed opposite to each other on both sides of the base layer 1; at the same time, the conductive layer 2 in the second single-layer region 102 and the reinforcing layer 11 are disposed opposite to each other on both sides of the base layer 1; and the reinforcing layer 11 is made of stainless steel (SUS), PI (polyimide), or PET (polyethylene terephthalate); the purpose is to enhance the hardness of the conductive layer in the FPC, thereby facilitating insertion, soldering, or improving insertion and removal durability.

[0038] Specifically, in some implementations, such as Figure 1 , 2 As shown in Figure 5, an electromagnetic shielding layer 12 is also provided on the base layer 1; the electromagnetic shielding layer 12 is connected to the surface of the insulating protective layer 3 away from the gold finger 21; and the projection of the electromagnetic shielding layer 12 toward the insulating protective layer 3 covers the insulating protective layer 3. Among them, the electromagnetic shielding layer 12 is made of copper alloy or silver alloy to achieve the effect of low cost and high shielding effectiveness.

[0039] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0040] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments described above, and any obvious improvements, substitutions, or modifications made by those skilled in the art based on this utility model are within the protection scope of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.

Claims

1. An FPC structure, characterized in that: It includes a base layer, a conductive layer, and an insulating protective layer; the conductive layer is connected to a side surface of the base layer; and a gold finger is provided on the conductive layer; the base layer has at least one edge; one side end of the gold finger extends toward the edge; the insulating protective layer is connected to the side surface of the gold finger away from the base layer, and one side end of the insulating protective layer extends through the edge; and an assembly gap is provided between the insulating protective layer and the edge.

2. The FPC structure according to claim 1, characterized in that: The width D of the assembly gap satisfies: 380μm≤D≤450μm.

3. The FPC structure according to claim 1 or 2, characterized in that: The insulating protective layer includes a wavy segment and at least two straight segments; the wavy segment and all the straight segments are sequentially arranged to surround each other; and the straight segments extend through the edge; the wavy segment is connected to the conductive layer.

4. The FPC structure according to claim 1 or 2, characterized in that: The gold finger includes at least one connecting strip; one side of the connecting strip extends toward the edge; and the width L of the connecting strip satisfies: A-0.02mm≤L≤A+0.03mm; wherein, A satisfies: 0.08mm≤A≤0.12mm.

5. The FPC structure according to claim 1, characterized in that: The insulating protective layer is made of polyimide or polyester film.

6. The FPC structure according to claim 1, characterized in that: The base layer is provided with a double-layer area and a second single-layer area and a first single-layer area connected to the double-layer area; in the double-layer area, the conductive layer is connected to two opposite side surfaces of the base layer; in the second single-layer area or the first single-layer area, the conductive layer is connected to one side surface of the base layer; and the gold finger is disposed on the second single-layer area or the first single-layer area.

7. The FPC structure according to claim 6, characterized in that: An external connection area is provided on the side of the second single-layer region away from the double-layer region and / or on the side of the first single-layer region away from the double-layer region; the gold finger is disposed on the external connection area.

8. The FPC structure according to claim 6 or 7, characterized in that: A reinforcing layer is also provided on the base layer; the conductive layer in the first single-layer region and the reinforcing layer are disposed opposite to each other on both sides of the base layer; and / or, the conductive layer in the second single-layer region and the reinforcing layer are disposed opposite to each other on both sides of the base layer.

9. The FPC structure according to claim 8, characterized in that: The reinforcing layer is made of stainless steel, polyimide, or polyethylene terephthalate.

10. The FPC structure according to claim 1, 6, or 7, characterized in that: An electromagnetic shielding layer is also provided on the base layer; the electromagnetic shielding layer is connected to the surface of the insulating protective layer away from the gold finger; and the projection of the electromagnetic shielding layer toward the insulating protective layer covers the insulating protective layer.

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