A flexible printed circuit board

Abstract

The utility model belongs to the technical field of circuit board, concretely relates to a flexible printed circuit board, including integrated circuit disc, external connecting disc and insulating separating component, one side surface of integrated circuit disc is equipped with integrated circuit layer, is equipped with external connecting area on external connecting disc, is equipped with golden finger in external connecting area, insulating separating component is connected on external connecting, insulating separating component and golden finger are in the same side surface of external connecting disc, and insulating separating component sets up between golden finger and integrated circuit layer, the utility model can improve the protection effect to integrated circuit layer, and then is favorable to the stability and security of improvement of use.

Description

Technical Field

[0001] This utility model belongs to the field of circuit board technology, and in particular relates to a flexible printed circuit board. Background Technology

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

[0003] However, in most existing flexible circuit boards, the gold finger mounting area is only separated from the IC (integrated circuit) by a small gap without a protective structure. The area where the gold fingers are soldered is not covered with a protective film, and the gold fingers can easily poke into the IC (integrated circuit) during soldering, affecting the stability of use. Utility Model Content

[0004] The purpose of this invention is to provide a flexible printed circuit board that addresses the shortcomings of existing technologies and improves the protective performance of the structure.

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

[0006] A flexible printed circuit board includes an integrated circuit disk, an external connection disk, and an insulating separator; an integrated circuit layer is provided on one side surface of the integrated circuit disk; an external connection area is provided on the external connection disk; a gold finger is provided in the external connection area; the insulating separator is connected to the external connection disk; the insulating separator and the gold finger are located on the same side surface of the external connection disk; and the insulating separator is disposed between the gold finger and the integrated circuit layer.

[0007] Preferably, the insulating separator includes an insulating adhesive and a first insulating coating; the insulating adhesive and the first insulating coating are sequentially connected to the integrated circuit disk along the direction of the gold finger toward the integrated circuit layer.

[0008] Preferably, the first insulating coating is selected from the first insulating oil material, and / or the insulating adhesive is selected from single-sided or double-sided adhesive.

[0009] Preferably, a first gap is provided between the first insulating coating and the integrated circuit layer.

[0010] Preferably, the relationship between the width d1 of the insulating adhesive, the width d2 of the first insulating coating, and the width d3 of the first gap satisfies: d1=(d2+d3)*A; where A satisfies: 1.0≤A≤1.5.

[0011] Preferably, the flexible printed circuit board further includes a wiring connection pad; the wiring connection pad is connected to the integrated circuit pad; the wiring connection pad is provided with at least one micro-connection point; and a blank area and a second insulating coating are provided between the micro-connection point and the integrated circuit layer; and the second insulating coating is connected to the integrated circuit pad; the blank area is provided between the second insulating coating and the micro-connection point.

[0012] Preferably, a second gap is provided between the second insulating coating and the integrated circuit layer.

[0013] Preferably, the integrated circuit layer includes a reinforcing underlayer, a substrate layer, a metal plating layer, and a coating layer arranged sequentially along the height direction; the external connection pad is connected to the substrate layer.

[0014] Preferably, the coating layer is disposed on the metal plating layer with its projection toward the substrate layer;

[0015] And / or, the relationship between the projected area S1 of the reinforcing underlayer toward the substrate layer and the projected area S2 of the metal plating layer toward the substrate layer satisfies: S1=B*S2; where B satisfies: 85%≤B≤96%.

[0016] Preferably, the substrate layer is selected from polyimide or polyester film;

[0017] And / or, the coating layer is selected from polyimide or polyester film;

[0018] And / or, the reinforcing substrate may be made of stainless steel, polyimide, or polyethylene terephthalate.

[0019] The beneficial effect of this utility model is that by using an insulating separator to separate the gold finger from the integrated circuit layer, it is beneficial to prevent burrs and other structures generated in the gold finger soldering area from piercing the integrated circuit layer, thereby improving the protection of the integrated circuit layer and thus improving the stability and safety of use. Attached Figure Description

[0020] The following will refer to the appendix. Figures 1-4 This section describes the features, advantages, and technical effects of exemplary embodiments of the present invention.

[0021] Figure 1 This is a schematic diagram of the structure of a flexible printed circuit board according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of a flexible printed circuit board according to an embodiment of the present invention;

[0023] Figure 3 This is a partially enlarged view of a flexible printed circuit board according to an embodiment of the present invention;

[0024] Figure 4 This is a cross-sectional view of a flexible printed circuit board according to an embodiment of the present invention.

[0025] In the diagram: 1-Integrated circuit disk; 11-Integrated circuit layer; 12-Connection disk; 121-Micro connection point; 13-Second insulating coating; 14-Blank area; 15-Second gap; 101-Substrate layer; 102-Metal plating layer; 103-Coating layer; 104-Reinforcing underlayer; 2-External connection disk; 21-External connection area; 211-Gold finger; 22-First gap; 3-Insulating separator; 31-Insulating adhesive; 32-First insulating coating. Detailed Implementation

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] The following is in conjunction with the appendix Figures 1-4 The present invention will be described in further detail, but this is not intended to limit the scope of the present invention.

[0032] like Figure 1 As shown, in one embodiment of this utility model, the flexible printed circuit board includes an integrated circuit disk 1, an external connection disk 2, and an insulating separator 3. An integrated circuit layer 11 is provided on one side surface of the integrated circuit disk 1. An external connection area 21 is provided on the external connection disk 2. A gold finger 211 is provided in the external connection area 21. The insulating separator 3 is connected to the external connection disk 2. The insulating separator 3 and the gold finger 211 are located on the same side surface of the external connection disk 2. The insulating separator 3 is disposed between the gold finger 211 and the integrated circuit layer 11.

[0033] The technical solution of this utility model uses an insulating separator to separate the gold finger from the integrated circuit layer, which helps to prevent burrs and other structures generated in the gold finger soldering area from piercing the integrated circuit layer, thereby improving the protection of the integrated circuit layer and thus improving the stability and safety of use.

[0034] Specifically, in some implementations, such as Figure 1 and 2As shown, the insulating separator 3 includes an insulating adhesive 31 and a first insulating coating 32; the insulating adhesive 31 and the first insulating coating 32 are sequentially connected to the integrated circuit disk 1 along the direction of the gold fingers 211 toward the integrated circuit layer 11. In some embodiments, the first insulating coating 32 is selected from a first insulating oil material, specifically mineral insulating oil or vegetable insulating oil. The insulating adhesive 31 is selected from single-sided or double-sided adhesives, specifically a single-sided adhesive combining a paper substrate and pressure-sensitive adhesive (PSA), a single-sided adhesive combining a film substrate and rubber-type pressure-sensitive adhesive, a double-sided adhesive combining a PET substrate and acrylic pressure-sensitive adhesive, or a double-sided adhesive combining a PET substrate and silicone pressure-sensitive adhesive. During assembly, the gold fingers are first soldered, then adhesive is applied, and finally the first insulating coating 32 is applied. This structure uses the insulating adhesive 31 to absorb any punctures or other extensions, thereby reducing the risk of the gold fingers penetrating the integrated circuit layer 11. Combined with the insulating effect of the first insulating coating 32, it prevents the gold fingers from directly contacting the integrated circuit layer 11 and causing short circuits, thus improving the safety of use.

[0035] Specifically, in some implementations, such as Figure 2 and 3 As shown, a first gap 22 is provided between the first insulating coating 32 and the integrated circuit layer 11. This structure avoids the first insulating coating 32 from directly contacting the integrated circuit layer 11 and affecting the conductivity of the integrated circuit layer 11 itself by adding the first gap 22.

[0036] Specifically, in some implementations, such as Figure 3 As shown, the relationship between the width d1 of the insulating adhesive 31, the width d2 of the first insulating coating 32, and the width d3 of the first gap 22 satisfies: d1=(d2+d3)*A; where A satisfies: 1.0≤A≤1.5. This structure, through the appropriate width relationship of the insulating adhesive 31, the first insulating coating 32, and the first gap 22, ensures the protective performance of the integrated circuit layer 11 and also avoids the area between the gold finger 211 and the integrated circuit layer 11 being too large, which would affect the overall power conduction performance.

[0037] Specifically, in some implementations, such as Figure 2 and 3As shown, the flexible printed circuit board also includes a wiring connection pad 12; the wiring connection pad 12 is connected to the integrated circuit pad 1; the wiring connection pad 12 is provided with at least one micro-connection point 121; and a blank area 14 and a second insulating coating 13 are provided between the micro-connection point 121 and the integrated circuit layer 11; the second insulating coating 13 is connected to the integrated circuit pad 1; the blank area 14 is provided between the second insulating coating 13 and the micro-connection point 121. The second insulating coating 13 is selected from a second insulating oil material, specifically mineral insulating oil or vegetable insulating oil. Furthermore, a second gap 15 is provided between the second insulating coating 13 and the integrated circuit layer 11. This structure avoids coating with EMI material and allows for the application of a green insulating oil material; ensuring the protective performance of the integrated circuit layer 11 and improving the overall power conduction performance.

[0038] Specifically, in some implementations, such as Figure 2 and 4 As shown, the integrated circuit layer 11 includes a reinforcing underlayer 104, a substrate layer 101, a metal plating layer 102, and a coating layer 103 arranged sequentially from bottom to top along the height direction; the external connection pad 2 is connected to the substrate layer 101. Wherein, as... Figure 4As shown, the projection of the coating layer 103 toward the substrate layer 101 covers the metal plating layer 102; the relationship between the projected area S1 of the reinforcing underlayer 104 toward the substrate layer 101 and the projected area S2 of the metal plating layer 102 toward the substrate layer 101 satisfies: S1=B*S2; where B satisfies: 85%≤B≤96%. This structure, through a relatively large coverage area, can ensure the reinforcing effect of the reinforcing underlayer 104 on the area of ​​the metal plating layer 102, and can also appropriately reduce the weight distribution; thereby improving the stability of use. Further, in some embodiments, the substrate layer 101 is selected as a polyimide (PI) or polyester (PET) film to achieve a thin and flexible feel. The metal plating layer 102 is selected as electrolytic copper foil or rolled copper foil, which presents fine circuit patterns after etching. 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. The coating layer 103 is made of polyimide (PI) or polyester (PET) film, and the material is consistent with that of the substrate layer 101; this protects the metal plating layer 102. The reinforcing underlayer 104 is made of stainless steel (SUS), PI (polyimide), or PET (polyethylene terephthalate); this aims to enhance the hardness of the metal plating layer 102 in the FPC, thereby facilitating insertion, soldering, or improving insertion and removal durability. This structure can form a reinforcing underlayer 104 - substrate layer 101 - adhesive layer (the material of which can be arbitrarily selected according to actual conditions) - metal plating layer 102 - coating layer 103. Of course, for those skilled in the art, the gold fingers 211 and the metal plating layer 102 are directly metallurgically bonded to the copper foil through the process of "copper foil patterning → surface treatment (gold plating)," without the need for additional soldering or mechanical connection.

[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. A flexible printed circuit board, characterized in that: The device includes an integrated circuit disk, an external connection disk, and an insulating separator. An integrated circuit layer is provided on one surface of the integrated circuit disk. An external connection area is provided on the external connection disk. A gold finger is provided within the external connection area. The insulating separator is connected to the external connection disk. The insulating separator and the gold finger are located on the same side surface of the external connection disk. Furthermore, the insulating separator is disposed between the gold finger and the integrated circuit layer.

2. The flexible printed circuit board according to claim 1, characterized in that: The insulating separator includes an insulating adhesive and a first insulating coating; the insulating adhesive and the first insulating coating are sequentially connected to the integrated circuit disk along the direction of the gold finger toward the integrated circuit layer.

3. The flexible printed circuit board according to claim 2, characterized in that: The first insulating coating is made of a first insulating oil material, and / or the insulating adhesive is made of single-sided or double-sided adhesive.

4. The flexible printed circuit board according to claim 2 or 3, characterized in that: A first gap is provided between the first insulating coating and the integrated circuit layer.

5. The flexible printed circuit board according to claim 4, characterized in that: The relationship between the width d1 of the insulating adhesive, the width d2 of the first insulating coating, and the width d3 of the first gap satisfies: d1=(d2+d3)*A; where A satisfies: 1.0≤A≤1.

5.

6. The flexible printed circuit board according to claim 1, characterized in that: The flexible printed circuit board further includes a wiring connection pad; the wiring connection pad is connected to the integrated circuit pad; the wiring connection pad is provided with at least one micro-connection point; and a blank area and a second insulating coating are provided between the micro-connection point and the integrated circuit layer; and the second insulating coating is connected to the integrated circuit pad; the blank area is provided between the second insulating coating and the micro-connection point.

7. The flexible printed circuit board according to claim 6, characterized in that: A second gap is provided between the second insulating coating and the integrated circuit layer.

8. The flexible printed circuit board according to claim 1, characterized in that: The integrated circuit layer includes a reinforcing underlayer, a substrate layer, a metal plating layer, and a coating layer arranged sequentially along the height direction; the external connection pad is connected to the substrate layer.

9. The flexible printed circuit board according to claim 8, characterized in that: The coating layer is disposed on the metal plating layer with its projection toward the substrate layer; And / or, the relationship between the projected area S1 of the reinforcing underlayer toward the substrate layer and the projected area S2 of the metal plating layer toward the substrate layer satisfies: S1=B*S2; where B satisfies: 85%≤B≤96%.

10. The flexible printed circuit board according to claim 8 or 9, characterized in that: The substrate layer is selected from polyimide or polyester film; And / or, the coating layer is selected from polyimide or polyester film; And / or, the reinforcing substrate may be made of stainless steel, polyimide, or polyethylene terephthalate.

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