Flexible printed circuit board and manufacturing equipment

Abstract

The utility model discloses a flexible printed circuit board. The flexible printed circuit board comprises a flexible coiled material and a conductive film, the length of the flexible coiled material is larger than or equal to 2 meters, and the flexible coiled material comprises a first side face and a second side face which are oppositely arranged. The conductive film is arranged on the first side face and stacked with the flexible coiled material, the conductive film comprises a curing adhesive layer and a conductive circuit embedded in the curing adhesive layer, the curing adhesive layer is arranged in a coating mode and forms a patterned groove through continuous rolling and curing, and the conductive circuit is formed in the patterned groove in a filling mode; the depth-to-width ratio of the depth to the width of the groove is greater than 1.2, the ultra-long flexible printed circuit board with the length exceeding 2 meters can be realized, the limitation of the depth-to-width ratio of the existing yellow light etching circuit can be broken through, the depth-to-width ratio can reach more than 1.2, and high-density and small-space wiring is facilitated. In addition, the utility model also discloses manufacturing equipment of the flexible printed circuit board.

Description

TECHNICAL FIELD

[0001] The utility model relates to printed circuit board technical field especially relates to a kind of flexible printed circuit board and manufacturing equipment. BACKGROUND

[0002] Printed circuit board (PCB) is an important basic component in electronic industry, and is widely used in computer, new energy vehicle, communication equipment, household appliance and other fields. Flexible printed circuit board (FPC) is a special type of printed circuit board, which has good flexibility and bendability, and is suitable for electronic equipment that needs to be bent or folded. With the development of technology, some fields, such as super-long LED light strip, battery module in power battery pack of new energy vehicle, etc. require flexible printed circuit board with a length of more than 2 meters. Due to the limitation of existing process and equipment, the current super-long flexible printed circuit board is generally spliced by two or more printed circuit boards through welding or connector, which makes the splicing place not easy to bend and easy to break. SUMMARY

[0003] Therefore, it is necessary to provide a flexible printed circuit board and manufacturing equipment to solve the above technical problems.

[0004] One technical scheme of the utility model is: a flexible printed circuit board, comprising:

[0005] Flexible web material, the length of which is greater than or equal to 2 meters, the flexible web material comprising a first side and a second side arranged opposite to each other;

[0006] Conductive film, arranged on the first side and laminated with the flexible web material, the conductive film comprising a cured adhesive layer and a conductive circuit embedded in the cured adhesive layer, the cured adhesive layer being coated and formed into a patterned groove through continuous rolling and curing, the conductive circuit being formed in the groove by filling, and the depth-width ratio of the groove being greater than 1.2.

[0007] In one embodiment, the flexible web material is PET web material, PI web material, PMMA web material or CPI web material, and the thickness of the flexible web material ranges from 0.0125mm to 0.05mm.

[0008] In one embodiment, the thickness of the cured adhesive layer ranges from 0.02mm to 0.04mm, the groove comprises a bottom wall and a side wall, and the distance from the bottom wall to the second side is 2μm-5μm.

[0009] In one embodiment, the depth-width ratio of the thickness and width of the conductive circuit is greater than 1.2.

[0010] In one embodiment, the conductive line is a copper line or a silver line.

[0011] In one embodiment, the cured adhesive layer is a UV cured adhesive layer.

[0012] In one embodiment, the flexible printed circuit board comprises two or more conductive films, which are arranged on the first side and / or the second side and laminated with the flexible web.

[0013] In one embodiment, a cover film is further included, which is laminated with the conductive film and covers the exposed conductive line.

[0014] The utility model also provides a flexible printed circuit board manufacturing equipment, it includes:

[0015] A winding and unwinding mechanism, which comprises an unwinding roller and a winding roller, and the flexible web is installed on the unwinding roller and the winding roller;

[0016] A coating mechanism, which is used for coating the UV cured adhesive on the flexible web;

[0017] A stamping mechanism, which comprises a die roller and an auxiliary roller, and the flexible web passes through the gap between the die roller and the auxiliary roller, and the die roller is provided with a patterned protrusion for stamping the UV cured adhesive to form a patterned groove with a depth-width ratio greater than 1.2 on the UV cured adhesive;

[0018] A curing mechanism, which comprises a UV curing device and an auxiliary platform, and the UV curing device is installed on the auxiliary platform, and the flexible web carrying the UV cured adhesive with the patterned groove moves parallel on the auxiliary platform to form a cured adhesive layer;

[0019] A filling mechanism, and the flexible web passes through the filling mechanism, which fills the copper material or silver material in the patterned groove;

[0020] A sintering mechanism, and the flexible web passes through the sintering mechanism, which sinters the copper material or silver material into a conductive line to form a conductive film.

[0021] In one embodiment, an attaching mechanism is further included, which uniformly attaches the cover film on the conductive film.

[0022] The utility model discloses the beneficial effect has: the utility model discloses the manufacturing process of flexible printed circuit board based on the embossing technology, utilize roll-to-roll embossing technology, can realize the super long flexible printed circuit board of length more than 2 meters, compared with the process of prior art, the application range of flexible printed circuit board is enlarged, satisfies more market demand. Meanwhile, the embossing technology that adoption can break through the limitation of the aspect ratio of the existing yellow light etching circuit, and the aspect ratio can reach 1.2 or more, is favorable to high density and small space wiring, improves the strength and toughness of conductive circuit, improves the conductivity and service life. And, the etching process is more environmental protection of embossing process because it does not need to use yellow light and other harmful chemical substances, thereby reducing the environmental pollution, reducing the production cost. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is the cross section structure schematic drawing of the utility model flexible printed circuit board;

[0024] Figure 2 It is another cross section structure schematic drawing of the utility model flexible printed circuit board;

[0025] Figure 3 It is another cross section structure schematic drawing of the utility model flexible printed circuit board;

[0026] Figure 4 It is another cross section structure schematic drawing of the utility model flexible printed circuit board;

[0027] Figure 5 It is another cross section structure schematic drawing of the utility model flexible printed circuit board;

[0028] Figure 6 It is another cross section structure schematic drawing of the utility model flexible printed circuit board manufacturing equipment. DETAILED DESCRIPTION

[0029] In order to facilitate understanding of the utility model, the utility model will be described more fully below with reference to the relevant drawings. The preferred embodiments of the utility model are shown in the drawings. However, the utility model can be realized in many different forms and is not limited to the embodiments described below. On the contrary, the purpose of providing these embodiments is to make the disclosure of the utility model more thorough and comprehensive.

[0030] It should be noted that when an element is referred to as "provided on" another element, it can be directly on the other element or there can be a middle element. When an element is referred to as "connected" to another element, it can be directly connected to the other element or there can be a middle element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not the only embodiments.

[0031] 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 belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0032] The utility model discloses a kind of flexible printed circuit boards, including flexible web and conductive film.Flexible web length is greater than or equal to 2 meters, and flexible web includes oppositely arranged first side and second side.Conductive film is arranged on the first side and is laminated with flexible web, and conductive film includes solidified adhesive layer and conductive circuit embedded in solidified adhesive layer, solidified adhesive layer is coated and is formed patterned groove by continuous roller pressing and solidification, and conductive circuit is formed in patterned groove by filling mode, and the depth-width ratio of the depth and width of groove is greater than 1.2.The utility model uses the manufacturing process of flexible printed circuit board based on stamping technology, using roll-to-roll stamping technology, can realize the super-long flexible printed circuit board of length more than 2 meters, compared with the process of prior art, expand the application range of flexible printed circuit board, satisfy more market demand.Meanwhile, the stamping technology used can break through the limitation of the depth-width ratio of existing yellow light etching circuit, and the depth-width ratio can reach more than 1.2, conducive to high-density and small-space wiring, improve the strength and toughness of conductive circuit, improve conductive performance and service life.And, stamping process is more environmentally friendly than etching process, because it does not need to use harmful chemicals such as yellow light, thereby reducing environmental pollution and reducing production cost.

[0033] Specifically, flexible web is PET web, PI web, PMMA web, CPI web, and the thickness of flexible web ranges from 0.0125mm to 0.05mm.The thickness of solidified adhesive layer ranges from 0.02mm to 0.04mm, and the groove includes bottom wall and side wall, and the distance from the bottom wall to the second side is 2μm-5μm.Solidified adhesive layer is UV solidified adhesive layer.

[0034] In one embodiment, the depth-width ratio of the thickness and width of conductive circuit is greater than 1.2, and the conductive circuit is copper wire or silver wire, conducive to high-density and small-space wiring, improve the strength and toughness of conductive circuit, improve conductive performance and service life.

[0035] In one embodiment, the flexible printed circuit board includes two or more conductive films, and the two or more conductive films are arranged on the first side and / or the second side and laminated with the flexible web.Using the same roll-to-roll stamping process, one layer, two layers or multiple layers of conductive film can be made on the first side and the second side of the flexible web, to meet the layout requirements of conductive circuit and the circuit requirements of electronic equipment.

[0036] In one embodiment, the flexible printed circuit board further comprises a cover film laminated with the conductive film and covering the exposed conductive circuit, satisfying the packaging requirement and protecting the conductive circuit.

[0037] The utility model discloses still disclose a kind of flexible printed circuit board manufacturing equipment, for making above-mentioned super-long flexible printed circuit board, and this manufacturing equipment includes take-up and pay-off mechanism, coating mechanism, impression mechanism, solidification mechanism, filling mechanism and sintering mechanism.Taking-up and pay-off mechanism includes unwinding roller and winding roller, and flexible web is installed to unwinding roller and winding roller.Unwinding roller and winding roller are located between coating mechanism, impression mechanism, solidification mechanism, filling mechanism and sintering mechanism, and flexible web is installed to realize each process section by taking-up and pay-off roll.In other embodiments, multiple sets of unwinding roller and winding roller can be provided, and other process sections can be separated and combined.Coating mechanism is used to coat UV curing adhesive on flexible web.Impression mechanism includes die roller and auxiliary roller, and flexible web passes through the gap of die roller and auxiliary roller, and die roller is provided with patterned protrusion for pressing UV curing adhesive, to form patterned groove with depth-width ratio greater than 1.2 on UV curing adhesive.Solidification mechanism includes UV curing piece and auxiliary platform, and UV curing piece is installed to auxiliary platform, and flexible web carries UV curing adhesive with patterned groove parallelly moves on auxiliary platform, and realizes solidification synchronously, to form cured adhesive layer.Flexible web passes through filling mechanism, and filling mechanism fills copper material or silver material in patterned groove.Flexible web passes through sintering mechanism, and sintering mechanism sinters copper material or silver material into conductive circuit to form conductive film.

[0038] In one embodiment, the manufacturing equipment further comprises an attaching mechanism, which uniformly attaches the cover film on the conductive film.

[0039] Below, please refer to the drawings, and example describes the flexible printed circuit board and manufacturing equipment of the utility model.

[0040] Please refer to Figure 1The utility model discloses a kind of flexible printed circuit boards 100, it includes flexible web 1 and conductive film 2.Flexible web 1 is polyimide (PI) film, its thickness is 0.0125mm-0.05mm, length is greater than or equal to 2m and upper limit of length is not limited.Flexible web 1 includes oppositely arranged first side 11 and second side 12.Conductive film 2 is arranged at first side 11 and is laminated with flexible web 1.Conductive film 2 includes solidified glue layer 21 and the conductive circuit 22 embedded in solidified glue layer 21.Solidified glue layer 21 is coated and is formed by continuous roller pressing and solidification strand formation patterned groove 211, and the conductive circuit 22 is formed in patterned groove 211 by filling mode.Groove 211 The depth and width ratio of depth and width are greater than 1.2.Utilize roll-to-roll imprinting technology, it can realize the super-long flexible printed circuit board 100 of length more than 2 meters, compared with the process of prior art, expand the application range of flexible printed circuit board 100, satisfy more market demand.Meanwhile, the imprinting technology used can break through the limitation of the depth-width ratio of existing yellow light etching circuit, and the depth-width ratio can reach more than 1.2, conducive to high-density and small-space wiring, improve the strength and toughness of conductive circuit 22, improve conductive performance and service life.And, imprinting process is more environmentally friendly than etching process, because it does not need to use harmful chemicals such as yellow light, thereby reducing environmental pollution, reduce production cost.

[0041] Solidified glue layer is UV solidified glue layer, its thickness range is 0.02mm-0.04mm, groove 211 includes bottom wall 2111 and side wall 2112, and the distance of bottom wall 211 from second side 12 is 2 μm-5 μm.Silver material or copper material is filled in groove 211, and copper wire or silver wire is formed after sintering, and the thickness of copper wire or silver wire is slightly less than, equal to or slightly greater than the depth of groove 211, therefore, the thickness and width ratio of conductive circuit 22 is also considered greater than 1.2, conducive to high-density and small-space wiring, improve the strength and toughness of conductive circuit 22, improve conductive performance and service life.

[0042] The manufacturing process of the flexible printed circuit board 100 is as follows: Step 1: preparing raw materials. First, a polyimide (PI) film with a thickness of 0.0125mm-0.05mm is prepared. Then, a UV curing adhesive with a solid content of 50%-70% is prepared. Next, a mold roller is prepared. Finally, silver or copper material with an average particle size of 2-10μm is prepared. Step 2: coating the UV curing adhesive. After the PI film is installed on the receiving roller and the feeding roller, the UV curing adhesive on the PI film is uniformly coated by the coating equipment, with a coating thickness of 0.02-0.04mm. Step 3: imprinting the circuit pattern. The PI film coated with the UV curing adhesive is passed through the imprinting mechanism and imprinted using a patterned raised mold with a circuit pattern. Step 4: curing the UV curing adhesive. The imprinted PI film is passed through the curing mechanism to cure the UV curing adhesive thereon, with a curing temperature of 200℃ and a curing time of 1h. Step 5: filling the metal material. The cured PI film is passed through the filling mechanism to fill the silver or copper material into the grooves thereon, with a filling thickness corresponding to the depth of the imprinted grooves. Step 6: sintering the metal powder. The PI film filled with the metal material is passed through the sintering mechanism to sinter the metal material thereon, forming conductive circuits embedded in the grooves. Through the above steps, a flexible printed circuit board 100 based on the imprinting technology can be obtained, which has a length of more than 2 meters, a depth-to-width ratio of more than 1.2, and a more environmentally friendly manufacturing process, suitable for application in high-density small-space wiring.

[0043] In other embodiments, step 7: attaching the cover film 3. The sintered PI film is passed through the attaching mechanism to uniformly attach the cover film 3 thereon, with a thickness of 0.0125-0.05mm, forming a flexible printed circuit board with the cover film 3.

[0044] In other embodiments, the flexible printed circuit board 100 includes two or more conductive films 2, which are arranged on the first side 11 and / or the second side 12 and stacked with the flexible web 1. Using the same roll-to-roll imprinting process, one, two or more conductive films 2 can be manufactured on the first side 11 and the second side 12 of the flexible web 1 to meet the layout requirements of the conductive circuits 22 and the circuit requirements of electronic devices. For example, Figure 3 In some embodiments, two conductive films 2 are arranged on the first side 11 and the second side 12 of the flexible substrate 1, respectively. For example, Figure 4 In some embodiments, two conductive films 2 are stacked on the first side 11, which facilitates the roll-to-roll imprinting process to form one layer of conductive film 2 on the first side 11 and then form another layer of conductive film 2 on the conductive film 2. The bottom wall 2111 of the groove 211 realizes insulation and isolation. For example, Figure 5 As shown in FIG. 11, two conductive films 2 are stacked on the first side 11, and one conductive film 2 is stacked on the second side 12.

[0045] Please refer to Figure 6 The utility model discloses a flexible circuit board manufacturing equipment 200 for manufacturing super-long flexible printed circuit board 100. The manufacturing equipment 200 includes a take-up and pay-off mechanism 201, a coating mechanism 202, a stamping mechanism 203, a curing mechanism 204, a filling mechanism 205 and a sintering mechanism 206. The take-up and pay-off mechanism 201 includes a pay-off roll 2011 and a take-up roll 2012, and the flexible web 1 is installed on the pay-off roll 2011 and the take-up roll 2012. The pay-off roll 2011 and the take-up roll 2012 are located between the coating mechanism 202, the stamping mechanism 203, the curing mechanism 204, the filling mechanism 205 and the sintering mechanism 206, and the flexible web 1 is installed to realize each process section through the take-up and pay-off. The stamping mechanism 203 includes a die roll 2031 and an auxiliary roll 2032, and the flexible web 1 passes through the gap between the die roll 2031 and the auxiliary roll 2032. The die roll 2031 is provided with a patterned protrusion for stamping the UV curing adhesive, so as to form a patterned groove with a depth-width ratio greater than 1.2 on the UV curing adhesive. The curing mechanism 204 includes a UV curing member 2041 and an auxiliary platform 2042, and the UV curing member 2041 is installed on the auxiliary platform 2042. The flexible web 1 carrying the UV curing adhesive with the patterned groove moves in parallel on the auxiliary platform 2042, and the curing is realized synchronously. The flexible web 1 passes through the filling mechanism 205, and the filling mechanism 205 fills the copper material or silver material in the patterned groove. The flexible web 1 passes through the sintering mechanism 206, and the sintering mechanism 206 sinters the copper material or silver material into a conductive circuit 22 to form a conductive film. In another embodiment, the manufacturing equipment 200 further includes a pasting mechanism, which uniformly pastes the cover film on the conductive film.

[0046] The flexible printed circuit board 100 disclosed by the utility model includes a flexible web 1 and a conductive film 2, and the conductive film 2 is formed through a roll-to-roll stamping process. The utility model can break through the limitation of the existing photolithography etching technology, and manufacture a super-long flexible printed circuit board with a length exceeding 2 meters and a flexible printed circuit board with a depth-width ratio exceeding 1.2. The utility model expands the application range of the flexible printed circuit board, meets the market demand for high-density and small-space wiring electronic equipment, especially in emerging technical fields such as super-long LED lamp strips and battery modules in power battery packs of new energy vehicles. Secondly, in the field of flexible material processing technology, the utility model uses a roll-to-roll stamping technology to coat UV curing adhesive on a PI film, uses a mold with a circuit pattern to stamp a groove corresponding to the circuit pattern on the UV curing adhesive and to cure the groove, and then fills silver material or copper material in the groove to form a metallized conductive circuit 22 after sintering. This process not only improves the processing efficiency of the flexible material, but also reduces material waste and production cost. In addition, the stamping process is more environmentally friendly than the etching process, so it also meets the current development trend of green manufacturing.

[0047] In order to make the above objects, features and advantages of the present application more obvious, the specific embodiments of the present application are described in detail above in combination with the drawings. In the above description, many specific details are set forth in order to fully understand the present application. However, the present application can be implemented in many other ways different from the above description, and those skilled in the art can make similar improvements without departing from the concept of the present application, so the present application is not limited by the above disclosed specific embodiments. Moreover, each technical feature of the above described embodiments can be combined arbitrarily, and in order to make the description simple, each technical feature in the above described embodiments is not described in all possible combinations, however, as long as the combination of these technical features does not exist contradictory, it should be considered as the scope of the present application.

[0048] The above described embodiments only express several implementation manners of the present application, the description is more specific and detailed, but it should not be understood as the limitation of the patent scope of the present application. It should be pointed out that for those skilled in the art, on the premise of not departing from the concept of the present application, a number of modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.

Claims

1. A flexible printed circuit board, characterized by, It comprises: A flexible roll material with a length greater than or equal to 2 meters, the flexible roll material comprising a first side and a second side arranged oppositely; A conductive film arranged on the first side and laminated with the flexible roll material, the conductive film comprising a cured adhesive layer and a conductive circuit embedded in the cured adhesive layer, the cured adhesive layer being arranged by coating and forming a patterned groove by continuous rolling and curing, the conductive circuit being formed in the groove by filling, the depth-to-width ratio of the groove being greater than 1.

2.

2. The flexible printed circuit board of claim 1, wherein, The flexible roll material is a PET roll material, a PI roll material, a PMMA roll material or a CPI roll material, and the thickness of the flexible roll material ranges from 0.0125mm to 0.05mm.

3. The flexible printed circuit board of claim 1, wherein, The thickness of the cured adhesive layer ranges from 0.02mm to 0.04mm, and the groove comprises a bottom wall and a side wall, the distance from the bottom wall to the second side being 2μm-5μm.

4. The flexible printed circuit board of claim 1, wherein, The depth-to-width ratio of the thickness and width of the conductive circuit is greater than 1.

2.

5. The flexible printed circuit board of claim 1, wherein, The conductive circuit is a copper wire or a silver wire.

6. The flexible printed circuit board of claim 1, wherein, The cured adhesive layer is a UV cured adhesive layer.

7. The flexible printed circuit board of claim 1, wherein, The flexible printed circuit board comprises two or more conductive films arranged on the first side and / or the second side and laminated with the flexible roll material.

8. The flexible printed circuit board of claim 1, wherein, It further comprises a cover film laminated with the conductive film and covering the exposed conductive circuit.

9. A flexible printed circuit board manufacturing apparatus, characterized by comprising: It comprises: A winding and unwinding mechanism comprising an unwinding roll and a winding roll, and a flexible roll material mounted on the unwinding roll and the winding roll; A coating mechanism for coating UV cured adhesive on the flexible roll material; A stamping mechanism comprising a die roll and an auxiliary roll, the flexible roll material passing through the gap between the die roll and the auxiliary roll, the die roll being provided with a patterned protrusion for stamping the UV cured adhesive to form a patterned groove with a depth-to-width ratio greater than 1.2 on the UV cured adhesive; A curing mechanism comprising a UV curing device and an auxiliary platform, the UV curing device being mounted on the auxiliary platform, and the flexible roll material carrying the UV cured adhesive with the patterned groove moving in parallel on the auxiliary platform to form a cured adhesive layer; A filling mechanism through which the flexible roll material passes, and the filling mechanism fills the groove with copper material or silver material; A sintering mechanism through which the flexible roll material passes, and the sintering mechanism sinters the copper material or silver material into a conductive circuit to form a conductive film.

10. The flexible printed circuit board manufacturing apparatus according to claim 9, wherein It further comprises an attaching mechanism for uniformly attaching a cover film on the conductive film.

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