Circuit board and manufacturing method thereof

Abstract

A circuit board comprises a laminated structure and a transparent resin layer wrapping the laminated structure. The laminated structure comprises a conductive circuit layer, a first electrochromic layer, a second electrochromic layer, a first transparent flexible conductive polymer layer and a second transparent flexible conductive polymer layer. The conductive circuit layer has a first surface and a second surface opposite to the first surface. The first electrochromic layer is arranged on the first surface, and the second electrochromic layer is arranged on the second surface. The first transparent flexible conductive polymer layer is arranged on the first electrochromic layer, and the second transparent flexible conductive polymer layer is arranged on the second electrochromic layer. The circuit board can improve transparency.

Description

Technical Field

[0001] This invention relates to a circuit board and a method for manufacturing the same, and more particularly to a transparent circuit board and a method for manufacturing the same. Background Technology

[0002] With the rapid development of electronic products, the requirements for circuit boards used in these products are becoming increasingly diverse. Currently, there is a type of transparent circuit board where the insulating substrate and cover film used to support and protect the conductive lines are made of transparent materials, making the internal conductive lines visible due to the transparency of the substrate and cover film. However, the conductive lines are made of light brown copper, which, being a light color, visually reduces the overall transparency of the circuit board. Summary of the Invention

[0003] At least one embodiment of the present invention provides a circuit board that can improve transparency.

[0004] At least another embodiment of the present invention provides a method for manufacturing the above-described circuit board to help improve the transparency of the circuit board.

[0005] A circuit board according to at least one embodiment of the present invention includes a multilayer structure and a transparent resin layer. The multilayer structure includes a conductive circuit layer, a first electrochromic layer, a second electrochromic layer, a first transparent flexible conductive polymer layer, and a second transparent flexible conductive polymer layer. The conductive circuit layer has a first surface and a second surface opposite to the first surface. The first electrochromic layer is disposed on the first surface, and the second electrochromic layer is disposed on the second surface. The first transparent flexible conductive polymer layer is disposed on the first electrochromic layer, and the second transparent flexible conductive polymer layer is disposed on the second electrochromic layer. The transparent resin layer covers the multilayer structure.

[0006] In at least one embodiment of the present invention, the linewidth of the conductive line layer is no greater than 25 micrometers.

[0007] In at least one embodiment of the present invention, at least one of the first surface and the second surface is a roughened surface.

[0008] In at least one embodiment of the present invention, the materials of the first electrochromic layer and the second electrochromic layer comprise polypyrrole, polyaniline, polyazine, polythiophene, polyindole, polycarbazole, or a combination thereof.

[0009] In at least one embodiment of the present invention, the oxidation color of the materials of the first electrochromic layer and the second electrochromic layer is black.

[0010] In at least one embodiment of the present invention, the materials of the first transparent flexible conductive polymer layer and the second transparent flexible conductive polymer layer comprise graphene and conductive polymer materials.

[0011] In at least one embodiment of the present invention, the material of the transparent resin layer comprises a polyester polymer compound.

[0012] In at least one embodiment of the present invention, the material of the transparent resin layer comprises polyethylene terephthalate, polyimide, polyethylene naphthalate, or a combination thereof.

[0013] In at least one embodiment of the present invention, the stacked structure further includes a first ion storage layer, a first electrolyte layer, a second ion storage layer, and a second electrolyte layer. The first ion storage layer is disposed between the first surface and the first electrochromic layer, and the first electrolyte layer is disposed between the first ion storage layer and the first electrochromic layer. The second ion storage layer is disposed between the second surface and the second electrochromic layer, and the second electrolyte layer is disposed between the second ion storage layer and the second electrochromic layer.

[0014] A method for manufacturing a circuit board according to at least another embodiment of the present invention provides a core board comprising a substrate and a conductive circuit layer disposed on the substrate. The conductive circuit layer has a first surface away from the substrate and a second surface opposite to the first surface. A first ion storage layer, a first electrolyte layer, a first electrochromic layer, and a first transparent flexible conductive polymer layer are sequentially formed on the first surface. A portion of the conductive circuit layer, a portion of the first ion storage layer, a portion of the first electrolyte layer, a portion of the first electrochromic layer, and a portion of the first transparent flexible conductive polymer layer are removed to form a first stacked structure. A first transparent resin layer is formed to cover the first stacked structure. After forming the first transparent resin layer to cover the first stacked structure, the substrate is removed to expose the second surface. After removing the substrate to expose the second surface, a second ion storage layer, a second electrolyte layer, a second electrochromic layer, and a second transparent flexible conductive polymer layer are sequentially formed on the second surface. A portion of the second ion storage layer, a portion of the second electrolyte layer, a portion of the second electrochromic layer, and a portion of the second transparent flexible conductive polymer layer are removed to form a second stacked structure. A second transparent resin layer is formed to cover the second laminated structure, the first laminated structure and the second laminated structure form a laminated structure, and the first transparent resin layer and the second transparent resin layer form a transparent resin layer to encapsulate the laminated structure. Attached Figure Description

[0015] Figure 1 This is a partial cross-sectional schematic diagram of a circuit board according to at least one embodiment of the present invention.

[0016] Figures 2A to 2K yes Figure 1 Partial cross-sectional views of the circuit board at different process stages. Detailed Implementation

[0017] In the following text, to clearly present the technical features of the present invention, the dimensions (e.g., length, width, thickness, and depth) of the elements (e.g., layers, films, substrates, and regions) in the accompanying drawings will be enlarged proportionally, and the number of some elements may be reduced. Therefore, the description and explanation of the embodiments below are not limited to the number of elements in the drawings or the size and shape of the elements, but should cover deviations in size, shape, and both caused by actual manufacturing processes and / or tolerances. For example, a flat surface shown in the drawings may have rough and / or non-linear characteristics, and an acute angle shown in the drawings may be rounded. Therefore, the elements presented in the accompanying drawings of the present invention are primarily for illustration and are not intended to precisely depict the actual shape of the elements, nor are they intended to limit the claims of the present invention.

[0018] Secondly, the terms "approximately," "about," or "substantially" used in this invention not only cover explicitly stated numerical values ​​and ranges, but also the permissible deviation range understood by those skilled in the art. This deviation range can be determined by errors generated during measurement, which may arise from limitations of the measurement system or process conditions. For example, two objects (e.g., planes or traces of a substrate) are "substantially parallel" or "substantially perpendicular," where "substantially parallel" and "substantially perpendicular" respectively represent that the parallelism and perpendicularity between the two objects can include non-parallelism and non-perpendicularity caused by the permissible deviation range.

[0019] The spatial relative terms used in this invention, such as "below," "under," "above," and "above," are for the convenience of describing the relative relationship between one element or feature and another, as illustrated in the figures. The true meaning of these spatial relative terms includes other orientations. For example, when the figures are rotated 180 degrees vertically, the relationship between one element and another may change from "below" or "under" to "above" or "above." Furthermore, the spatial relative descriptions used in this invention should be interpreted in the same way.

[0020] It should be understood that although the present invention may use terms such as "first," "second," and "third" to describe various elements or features, these elements or features should not be limited by these terms. These terms are primarily used to distinguish one element from another, or one feature from another. Furthermore, the term "or" as used in the present invention may, as appropriate, include any combination of one or more of the associated listed items.

[0021] Although this invention uses a series of operations or steps to illustrate the manufacturing method, the order in which these operations or steps are shown should not be construed as a limitation of the invention. For example, some operations or steps may be performed in a different order and / or simultaneously with other steps. Furthermore, each operation or step described herein may comprise several sub-steps or actions.

[0022] Furthermore, the present invention can be implemented or applied through other different specific embodiments, and the details of the present invention can also be combined, modified and changed in various embodiments based on different viewpoints and applications without departing from the concept of the present invention.

[0023] Figure 1 This is a partial cross-sectional schematic diagram of a circuit board according to at least one embodiment of the present invention. Please refer to... Figure 1 The circuit board 10 includes a stacked structure 100 and a transparent resin layer 200, the transparent resin layer 200 covering the stacked structure 100. The stacked structure 100 includes a conductive circuit layer 101, a first electrochromic layer 104A, a second electrochromic layer 104B, a first transparent flexible conductive polymer layer 105A, and a second transparent flexible conductive polymer layer 105B.

[0024] The conductive circuit layer 101 has a first surface S1 and a second surface S2 opposite to the first surface S1. A first electrochromic layer 104A is disposed on the first surface S1, and a second electrochromic layer 104B is disposed on the second surface S2. A first transparent flexible conductive polymer layer 105A is disposed on the first electrochromic layer 104A, and a second transparent flexible conductive polymer layer 105B is disposed on the second electrochromic layer 104B. That is, the first electrochromic layer 104A is located between the first surface S1 and the first transparent flexible conductive polymer layer 105A of the conductive circuit layer 101, while the second electrochromic layer 104B is located between the second surface S2 and the second transparent flexible conductive polymer layer 105B of the conductive circuit layer 101.

[0025] Since the first electrochromic layer 104A and the second electrochromic layer 104B are respectively disposed on the first surface S1 and the second surface S2 of the conductive line layer 101, the voltage between the conductive line layer 101 and the first transparent flexible conductive polymer layer 105A and the second transparent flexible conductive polymer layer 105B can be controlled to determine whether the first electrochromic layer 104A and the second electrochromic layer 104B change color. If they turn black, the conductive line layer 101 located between the first electrochromic layer 104A and the second electrochromic layer 104B can avoid reflecting light, making it difficult for the human eye to perceive the existence of the lines, thereby improving the transparency of the circuit board 10. In addition, by setting the first transparent flexible conductive polymer layer 105A and the second transparent flexible conductive polymer layer 105B, the stacked structure 100 can be bent, thereby improving the bendability of the circuit board 10.

[0026] In some embodiments, the linewidth of the conductive circuit layer 101 is no greater than 25 micrometers, for example, it can be 15 micrometers. Since if the linewidth is greater than 25 micrometers, even if the first electrochromic layer 104A and the second electrochromic layer 104B corresponding to the conductive circuit layer 101 turn black, the human eye may still perceive the black lines. Therefore, the aforementioned linewidth design can effectively improve the transparency of the circuit board 10. At least one of the first surface S1 and the second surface S2 of the conductive circuit layer 101 is a roughened surface, which allows light to diffuse, making it difficult for the human eye to perceive the presence of the lines, thereby improving the transparency of the circuit board 10. Furthermore, it can also increase the adhesion between the conductive circuit layer 101 and other layers, improving the reliability of the circuit board 10.

[0027] In some embodiments, the materials of the first electrochromic layer 104A and the second electrochromic layer 104B may include polypyrole, polyaniline, polyazulene, polythiophene, polyindole, polycarbazole, or combinations thereof.

[0028] For example, polypyrrole can be used, which has a lower oxidation potential, higher current efficiency, and longer repetition life compared to other materials. Therefore, as the material for the first electrochromic layer 104A and the second electrochromic layer 104B, it can have higher stability, which can improve the reliability of the circuit board 10. In addition, the color of polypyrrole when oxidized is black, compared to other materials which may be green or dark red. The black oxidation color of the materials of the first electrochromic layer 104A and the second electrochromic layer 104B makes it less likely for the human eye to detect the presence of the circuit, thereby improving the transparency of the circuit board 10.

[0029] In some embodiments, the materials of the first transparent flexible conductive polymer layer 105A and the second transparent flexible conductive polymer layer 105B may include graphene and conductive polymer materials. The material of the transparent resin layer 200 may include polyester polymer compounds. The material of the transparent resin layer 200 may include polyethylene terephthalate (PET), polyimide (PI), polyethylene naphthalate (PEN), or combinations thereof. By selecting the aforementioned materials, the transparency and flexibility of the circuit board 10 can be effectively improved.

[0030] Please continue reading. Figure 1The laminated structure 100 further includes a first ion storage layer 102A, a first electrolyte layer 103A, a second ion storage layer 102B, and a second electrolyte layer 103B. The first ion storage layer 102A is disposed between the first surface S1 and the first electrochromic layer 104A, and the first electrolyte layer 103A is disposed between the first ion storage layer 102A and the first electrochromic layer 104A. The second ion storage layer 102B is disposed between the second surface S2 and the second electrochromic layer 104B, and the second electrolyte layer 103B is disposed between the second ion storage layer 102B and the second electrochromic layer 104B.

[0031] In some embodiments, the materials of the first electrolyte layer 103A and the second electrolyte layer 103B may include electrolyte materials such as lithium perchlorate and sodium perchlorate. The first ion storage layer 102A and the second ion storage layer 102B are used to store corresponding ions with opposite charges when the first electrochromic layer 104A and the second electrochromic layer 104B undergo redox reactions, thereby maintaining charge balance.

[0032] Figures 2A to 2K yes Figure 1 Partial cross-sectional views of the circuit board at different manufacturing stages. Please refer to... Figure 2A A core board C is provided, comprising a substrate B and a conductive line layer 101 disposed on the substrate B. The conductive line layer 101 has a first surface S1 away from the substrate B and a second surface S2 opposite to the first surface S1.

[0033] Please see Figures 2B to 2E A first ion storage layer 102A, a first electrolyte layer 103A, a first electrochromic layer 104A, and a first transparent flexible conductive polymer layer 105A are sequentially formed on the first surface S1. Specifically, firstly, as... Figure 2B As shown, a first ion storage layer 102A is formed on the first surface S1. Next, as... Figure 2C As shown, a first electrolyte layer 103A is formed on the first ion storage layer 102A. As... Figure 2D As shown, a first electrochromic layer 104A is formed on the first electrolyte layer 103A. Next, as... Figure 2E As shown, a first transparent flexible conductive polymer layer 105A is formed on the first electrochromic layer 104A.

[0034] In some embodiments, the first ion storage layer 102A, the first electrolyte layer 103A, and the first electrochromic layer 104A may be formed by a coating process and a baking process. The first transparent flexible conductive polymer layer 105A may be formed by a coating process and a baking process or a photocuring process.

[0035] Please see Figures 2F to 2HA portion of the conductive circuit layer 101, a portion of the first ion storage layer 102A, a portion of the first electrolyte layer 103A, a portion of the first electrochromic layer 104A, and a portion of the first transparent flexible conductive polymer layer 105A are removed to form a first stacked structure 110. Specifically, firstly, as... Figure 2F As shown, photoresist F is formed on the first transparent flexible conductive polymer layer 105A. Next, as... Figure 2G As shown, portions of the first ion storage layer 102A, the first electrolyte layer 103A, the first electrochromic layer 104A, and the first transparent flexible conductive polymer layer 105A not covered by the photoresist F are removed to expose a portion of the conductive circuit layer 101. Next, as... Figure 2H As shown, the exposed portion of the conductive line layer 1011 is removed and the photoresist F is removed to form the first stacked structure 110.

[0036] In some embodiments, a portion of the first ion storage layer 102A, a portion of the first electrolyte layer 103A, a portion of the first electrochromic layer 104A, and a portion of the first transparent flexible conductive polymer layer 105A may be removed by laser processing. A portion of the conductive circuit layer 101 may be removed by etching processing.

[0037] Please see Figure 2I A first transparent resin layer 210 is formed to cover the first laminated structure 110. Specifically, the first transparent resin layer 210 covers the surface and sidewalls of the first laminated structure 110, that is, the first transparent resin layer 210 covers the surface and sidewalls of the first transparent flexible conductive polymer layer 105A, the sidewalls of the first electrochromic layer 104A, the sidewalls of the first electrolyte layer 103A, the sidewalls of the first ion storage layer 102A, and the sidewalls of the conductive circuit layer 101. In some embodiments, the first transparent resin layer 210 may be formed by a lamination process.

[0038] Please see Figure 2J After forming the first transparent resin layer 210 to cover the first laminated structure 110, the substrate B is removed to expose the second surface S2. (See also...) Figure 2K After removing the substrate B to expose the second surface S2, a second ion storage layer 102B, a second electrolyte layer 103B, a second electrochromic layer 104B, and a second transparent flexible conductive polymer layer 105B are sequentially formed on the second surface S2. A portion of the second ion storage layer 102B, a portion of the second electrolyte layer 103B, a portion of the second electrochromic layer 104B, and a portion of the second transparent flexible conductive polymer layer 105B are removed to form a second stacked structure 120.

[0039] The steps and processes for sequentially forming a second ion storage layer 102B, a second electrolyte layer 103B, a second electrochromic layer 104B, and a second transparent flexible conductive polymer layer 105B on the second surface S2 are as follows: Figures 2B to 2E Similarly, the same characteristics will not be described again. The steps and processes of removing a portion of the second ion storage layer 102B, a portion of the second electrolyte layer 103B, a portion of the second electrochromic layer 104B, and a portion of the second transparent flexible conductive polymer layer 105B to form the second stacked structure 120 are the same as those described above. Figure 2F and Figure 2G Similarly, the same characteristics will not be repeated here.

[0040] Please see Figure 1 A second transparent resin layer 220 is formed to cover the second laminated structure 120. The first laminated structure 110 and the second laminated structure 120 form a laminated structure 100. The first transparent resin layer 210 and the second transparent resin layer 220 form a transparent resin layer 200 to encapsulate the laminated structure 100. The steps and processes for forming the second transparent resin layer 220 to cover the second laminated structure 120 are similar to those described above. Figure 2I Similarly, the same characteristics will not be repeated here.

[0041] In summary, in the circuit board and manufacturing method of the present invention according to at least one embodiment, since the electrochromic layer is disposed on the surface of the conductive circuit layer, the color change of the electrochromic layer can be determined by controlling the voltage. If it turns black, the reflection of light by the conductive circuit layer located between the electrochromic layers can be avoided, making it difficult for the human eye to perceive the presence of the circuit, thereby improving the transparency of the circuit board. In addition, the bendability of the circuit board can be improved by providing a transparent flexible conductive polymer layer.

[0042] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

[0043] [Symbol Explanation]

[0044] 10: Circuit board

[0045] 100: Stacked structure

[0046] 101: Conductive circuit layer

[0047] 102A: First ion storage layer

[0048] 102B: Second ion storage layer

[0049] 103A: First electrolyte layer

[0050] 103B: Second electrolyte layer

[0051] 104A: First electrochromic layer

[0052] 104B: Second electrochromic layer

[0053] 105A: First transparent flexible conductive polymer layer

[0054] 105B: Second transparent flexible conductive polymer layer

[0055] 110: First stacked structure

[0056] 120: Second stacked structure

[0057] 200: Transparent resin layer

[0058] 210: First transparent resin layer

[0059] 220: Second transparent resin layer

[0060] C: Core Board

[0061] B: Substrate

[0062] F: Light Obstruction

[0063] S1: First surface

[0064] S2: Second surface.

Claims

1. A circuit board, characterized in that, include: Layered structures, including: A conductive circuit layer having a first surface and a second surface opposite to the first surface; A first electrochromic layer is disposed on the first surface; A second electrochromic layer is disposed on the second surface; A first transparent, flexible, conductive polymer layer is disposed on the first electrochromic layer; and A second transparent flexible conductive polymer layer is disposed on the second electrochromic layer; and a transparent resin layer covers the stacked structure.

2. The circuit board according to claim 1, characterized in that, The linewidth of the conductive circuit layer is no greater than 25 micrometers.

3. The circuit board according to claim 1, characterized in that, At least one of the first surface and the second surface is a roughened surface.

4. The circuit board according to claim 1, characterized in that, The materials of the first electrochromic layer and the second electrochromic layer include polypyrrole, polyaniline, polyazine, polythiophene, polyindole, polycarbazole, or combinations thereof.

5. The circuit board according to claim 1, characterized in that, The materials of the first electrochromic layer and the second electrochromic layer are oxidized to black.

6. The circuit board according to claim 1, characterized in that, The materials of the first transparent flexible conductive polymer layer and the second transparent flexible conductive polymer layer include graphene and conductive polymer materials.

7. The circuit board according to claim 1, characterized in that, The material of the transparent resin layer includes polyester polymer compounds.

8. The circuit board according to claim 1, characterized in that, The material of the transparent resin layer includes polyethylene terephthalate, polyimide, polyethylene naphthalate, or a combination thereof.

9. The circuit board according to claim 1, characterized in that, The stacked structure further includes: A first ion storage layer is disposed between the first surface and the first electrochromic layer; A first electrolyte layer is disposed between the first ion storage layer and the first electrochromic layer; A second ion storage layer is disposed between the second surface and the second electrochromic layer; and The second electrolyte layer is disposed between the second ion storage layer and the second electrochromic layer.

10. A method for manufacturing a circuit board, characterized in that, include: A core board is provided, including a substrate and a conductive circuit layer disposed on the substrate, wherein the conductive circuit layer has a first surface away from the substrate and a second surface opposite to the first surface; A first ion storage layer, a first electrolyte layer, a first electrochromic layer, and a first transparent flexible conductive polymer layer are sequentially formed on the first surface; A portion of the conductive circuit layer, a portion of the first ion storage layer, a portion of the first electrolyte layer, a portion of the first electrochromic layer, and a portion of the first transparent flexible conductive polymer layer are removed to form a first stacked structure. A first transparent resin layer is formed to cover the first laminated structure; After the first transparent resin layer is formed to cover the first laminated structure, the substrate is removed to expose the second surface; After removing the substrate to expose the second surface, a second ion storage layer, a second electrolyte layer, a second electrochromic layer and a second transparent flexible conductive polymer layer are sequentially formed on the second surface. A portion of the second ion storage layer, a portion of the second electrolyte layer, a portion of the second electrochromic layer, and a portion of the second transparent flexible conductive polymer layer are removed to form a second stacked structure; as well as A second transparent resin layer is formed to cover the second laminated structure, wherein the first laminated structure and the second laminated structure form a laminated structure, and the first transparent resin layer and the second transparent resin layer form a transparent resin layer to encapsulate the laminated structure.

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