Single-sided flexible circuit board

Abstract

The utility model discloses a single-sided flexible circuit board, which comprises a single-sided base material and a first covering film, the single-sided base material comprises a base material substrate film and a copper foil layer, the copper foil layer is arranged on the upper surface of the base material substrate film, and the first covering film is arranged on the lower surface, far away from the copper foil layer, of the base material substrate film. According to the utility model, before circuit manufacturing is carried out on the single-sided base material, a layer of first covering film is additionally arranged on the lower surface, far away from the copper foil layer, of the single-sided base material, and an additional tearing process is not carried out when the layer of first covering film is attached, so that a product is protected, the product is protected from wrinkling, and the use effect of the product is improved.

Description

Technical Field

[0001] This utility model relates to the field of circuit boards, and in particular to a single-sided flexible circuit board. Background Technology

[0002] As is well known, a single-sided flexible printed circuit (FPC) is a type of FPC circuit board that uses a single-layer substrate. Due to its unique flexibility and bendability, single-sided flexible printed circuit boards are widely used in various portable electronic products and wearable devices. However, existing single-sided flexible printed circuit boards are prone to wrinkling during manufacturing and use, affecting their performance. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a single-sided flexible circuit board to solve the problem that existing single-sided flexible circuit boards are prone to wrinkling.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a single-sided flexible circuit board, which includes a single-sided substrate and a first cover film. The single-sided substrate includes a substrate base film and a copper foil layer. The copper foil layer is disposed on the upper surface of the substrate base film, and the first cover film is disposed on the lower surface of the substrate base film away from the copper foil layer.

[0005] Furthermore, in the single-sided flexible circuit board of this utility model, the first covering film is a polyimide film.

[0006] Furthermore, in the single-sided flexible circuit board of this utility model, the thickness of the first covering film is 12.5-14.5 μm.

[0007] Furthermore, in the single-sided flexible circuit board of this utility model, the first cover film is adhered to the lower surface of the substrate base film by an adhesive.

[0008] Furthermore, in the single-sided flexible circuit board of this utility model, the substrate base film is a polyimide film.

[0009] Furthermore, in the single-sided flexible circuit board of this utility model, the thickness of the substrate base film is 22.5-27.5 μm.

[0010] Furthermore, in the single-sided flexible circuit board of this utility model, the thickness of the copper foil layer is 11-13 μm.

[0011] Furthermore, the single-sided flexible circuit board of this utility model also includes a second cover film, which is disposed on the upper surface of the single-sided substrate away from the first cover film.

[0012] Furthermore, in the single-sided flexible circuit board of this utility model, the second covering film is a polyimide film.

[0013] Furthermore, in the single-sided flexible circuit board of this utility model, the thickness of the second cover film is 12-13 μm.

[0014] The beneficial effects of this invention are as follows: Before fabricating the circuit on the single-sided substrate, a first cover film is added to the back of the single-sided substrate, that is, to the lower surface of the substrate base film away from the copper foil layer. This first cover film is applied without any additional peeling process, ensuring that the prepared single-sided flexible circuit board is always covered by the first cover film on the back of the single-sided substrate. In other words, the first cover film is always located on the back of the product to protect it, thereby preventing wrinkles and improving its usability. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the single-sided flexible circuit board according to one embodiment of the present invention from one perspective.

[0016] Figure 2 This is a schematic diagram illustrating the preparation process of applying a first cover film to a single-sided substrate in the single-sided flexible circuit board of this utility model.

[0017] Label Explanation:

[0018] 1. Single-sided substrate; 11. Substrate base film; 12. Copper foil layer;

[0019] 2. First covering film;

[0020] 3. Second covering film;

[0021] 4. First cover film loading roll; 41. First cover film release paper recycling roll;

[0022] 5. Single-sided substrate loading roll; 51. Protective film spare recycling roll;

[0023] 6. Support wheels; 61. Cleaning wheels

[0024] 7. Press roller;

[0025] 8. Tension wheel;

[0026] 9. Material recycling rolls. Detailed Implementation

[0027] To explain in detail the technical content, objectives, and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0028] It's important to note that single-sided FPC flexible circuit boards are FPC circuit boards using a single-layer substrate. Typically, a single-sided FPC flexible circuit board has only one side of copper foil, and the circuitry can only be laid out on this one side. The manufacturing process of single-sided FPC flexible circuit boards is relatively simple, and they are well-suited for achieving high-density circuit layouts, especially for simple circuit designs and mass production. Furthermore, because their circuit layout is readily apparent, maintenance and repair are relatively convenient, and manufacturing costs are low. Therefore, single-sided FPC flexible circuit boards have a wide range of applications (such as single-sided layout circuit components like displays and buttons in electronic products; circuit system design in sensors, automotive electronics, and instruments; and in industries such as home appliances, security, and communications). In summary, single-sided FPC flexible circuit boards are widely used in consumer electronics products due to their low cost, ease of maintenance, and suitability for simple circuit designs, meeting the needs of large-scale production and maintenance. However, wrinkles are prone to occur during the product (i.e., single-sided FPC flexible circuit board) manufacturing process. To reduce the occurrence of wrinkles, a layer of micro-connecting film (PET) can be set on the back of the substrate, or a guide plate can be added during the manufacturing process. After the finishing processes such as cover film, ink, and chemical gold are completed, the micro-connecting film (PET) or guide plate can be manually peeled off. However, the products manufactured during the peeling process will still show wrinkles of varying degrees.

[0029] Therefore, in this invention, a first cover layer 2 (CVL) is applied to the single-sided substrate 1 before circuit fabrication. This first cover layer 2 is applied to the back (PI side) of the single-sided substrate 1. This first cover layer 2 provides continuous protection to the PI side of the product without requiring any additional removal process. It should be noted that this added first cover layer 2 protects the product from wrinkles while also meeting the overall thickness requirements of the product.

[0030] Please refer to Figures 1 to 2 This utility model provides a single-sided flexible circuit board, which includes a single-sided substrate 1 and a first cover film 2. The single-sided substrate 1 includes a substrate base film 11 and a copper foil layer 12. The copper foil layer 12 is disposed on the upper surface of the substrate base film 11, and the first cover film 2 is disposed on the lower surface of the substrate base film 11 away from the copper foil layer 12. It should be noted that the entire lower surface of the substrate base film 11 away from the copper foil layer 12 is covered by the first cover film 2, that is, the first cover film 2 completely covers the lower surface of the substrate base film 11.

[0031] As can be seen from the above description, the beneficial effects of this utility model are as follows: Before fabricating the circuit on the single-sided substrate 1, a first cover layer 2 (CVL) is added to the back side (i.e., the PI side) of the single-sided substrate 1, that is, the lower surface of the substrate base film 11 away from the copper foil layer 12. No additional peeling process is required to adhere this first cover layer 2, ensuring that the prepared single-sided flexible circuit board is always covered by the first cover layer on the back side of the single-sided substrate. In other words, the first cover layer 2 is always located on the PI side of the product (i.e., the single-sided FPC flexible circuit board) to protect the product, thereby preventing wrinkles and improving the product's performance.

[0032] Furthermore, in the single-sided flexible circuit board of this utility model, the first cover film 2 is a polyimide film, and the thickness of the first cover film 2 is 12.5-14.5 μm. It should be noted that the thickness of the first cover film can be selected according to actual needs and is not limited here. In practical applications, the first cover film 2 can be adhered to the lower surface of the substrate base film 11 using an adhesive, wherein the adhesive thickness can be 15 μm.

[0033] Furthermore, in the single-sided flexible circuit board of this utility model, the substrate base film 11 is a polyimide film, and the thickness of the substrate base film 11 is 22.5-27.5 μm. It should be noted that the thickness of the substrate base film 11 can be selected according to actual needs and is not limited here.

[0034] Furthermore, in the single-sided flexible circuit board described in this utility model, the thickness of the copper foil layer 12 is 11-13 μm. It should be noted that the thickness of the copper foil layer 12 can be selected according to actual needs and is not limited here.

[0035] Furthermore, the single-sided flexible circuit board of this utility model also includes a second cover film 3, which is disposed on the upper surface of the single-sided substrate 1 away from the first cover film 2.

[0036] Furthermore, in the single-sided flexible circuit board of this utility model, the second cover film 3 is a polyimide film, and the thickness of the second cover film 3 is 12-13 μm. It should be noted that the thickness of the second cover film 3 can be selected according to actual needs and is not limited here. In practical applications, the second cover film 3 can be pasted onto the upper surface of the single-sided substrate 1 using an adhesive, wherein the adhesive thickness can be 15 μm.

[0037] In addition, such as Figure 2As shown, this utility model also provides a coating operation for a single-sided substrate 1 and a first cover film 2 in a single-sided flexible circuit board. In practical applications, before fabricating circuits on the single-sided substrate 1, the above-mentioned coating operation is performed. The coating operation process includes the following steps: First, prepare materials such as the single-sided substrate 1 and the first cover film 2, adjust the parameters of the equipment, etc., then coat the back of the single-sided substrate 1 with the first cover film 2, and finally roll it up. Specifically: the first cover film is fed through the first cover film feeding roll 4, and the release paper of the first cover film after feeding can be recycled based on the first cover film release paper recycling roll 41. At the same time, the single-sided substrate is fed through the single-sided substrate feeding roll 5, and the protective film after feeding can be recycled through the protective film spare recycling roll 51. Before applying the first covering film 2 and the single-sided substrate 1, the first covering film 2 and the single-sided substrate 1 are cleaned using support rollers 6 and cleaning rollers 61. After cleaning, the covering film is fixed using pressure rollers 7. Then, the single-sided substrate 1 covered with the first covering film 2 is operated using corresponding support rollers 6 and tension rollers 8 to maintain tension and prevent loosening or breakage. Finally, the processed material is recycled using material recycling rolls 9.

[0038] Please refer to Figures 1 to 2 The first embodiment of this utility model is: a single-sided flexible circuit board, which includes a second cover film 3, a single-sided substrate 1 and a first cover film 2 arranged sequentially from top to bottom. The second cover film 3 is disposed on the front side (i.e., the upper surface) of the single-sided substrate 1, and the first cover film 2 is disposed on the back side (i.e., the PI side / lower surface) of the single-sided substrate 1.

[0039] As an example, Table 1 lists the basic components of the single-sided flexible circuit board in this embodiment, as shown below:

[0040]

[0041] Table 1

[0042] In this embodiment, as Figure 1As shown in Table 1 above, the single-sided substrate 1 includes a substrate base film 11 and a copper foil layer 12. The copper foil layer 12 is disposed on the upper surface of the substrate base film 11. The substrate base film 11 is a polyimide film with a thickness of 25 μm, and the copper foil layer 12 has a thickness of 12 μm. A second cover film 3 is provided on the upper surface of the single-sided substrate 1, that is, the second cover film 3 is disposed on the upper surface of the copper foil layer 12 away from the substrate base film 11. The second cover film 3 is adhered to the upper surface of the copper foil layer 12 by an adhesive with a thickness of 16 μm. The second cover film 3 is a polyimide film with a thickness of 12.5 μm. A first cover film 2 is provided on the lower surface of the single-sided substrate 1. That is, the first cover film 2 is attached to the lower surface of the substrate base film 11 away from the copper foil layer 12 by an adhesive. The thickness of the adhesive is 16 μm, and the first cover film 2 is a polyimide film with a thickness of 12.5 μm.

[0043] In summary, the single-sided flexible circuit board provided by this utility model breaks with conventional operating methods. Before fabricating the circuit on the single-sided substrate, a first cover film is added to the back of the substrate (i.e., the PI side). This is improved through a special stacking method. This first cover film is always attached to protect the PI side of the product, eliminating the need for an additional tearing process, allowing the product to be shipped to the customer. In this utility model, the added first cover film not only protects the product from wrinkles but also meets the customer's overall product thickness requirements.

[0044] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent modifications made based on the content of this utility model specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A single-sided flexible circuit board, characterized in that, The device includes a single-sided substrate and a first cover film. The single-sided substrate includes a substrate base film and a copper foil layer. The copper foil layer is disposed on the upper surface of the substrate base film. The first cover film is disposed on the lower surface of the substrate base film away from the copper foil layer and completely covers the lower surface of the substrate base film. The thickness of the first cover film is 12.5-14.5 μm. It also includes a second cover film, which is disposed on the upper surface of the single-sided substrate away from the first cover film, and the thickness of the second cover film is 12-13 μm.

2. The single-sided flexible circuit board according to claim 1, characterized in that, The first covering film is a polyimide film.

3. The single-sided flexible circuit board according to claim 1, characterized in that, The first cover film is adhered to the lower surface of the substrate base film by an adhesive.

4. The single-sided flexible circuit board according to claim 1, characterized in that, The substrate base film is a polyimide film.

5. The single-sided flexible circuit board according to claim 1, characterized in that, The thickness of the substrate base film is 22.5-27.5 μm.

6. The single-sided flexible circuit board according to claim 1, characterized in that, The thickness of the copper foil layer is 11-13 μm.

7. The single-sided flexible circuit board according to claim 1, characterized in that, The second covering film is a polyimide film.

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