KR100679844B1 - Roll to roll form manufacture methode of flexible printed circuit board using mechanical type drill - Google Patents

Abstract

The present invention relates to a via hole forming apparatus and a method of forming a double-sided flexible printed circuit board using a mechanical drilling machine, in the production of a flexible printed circuit board, a copper foil sheet in a plurality of layers to overlap the mechanical drilling machine in a roll-to-roll manner It is to improve the productivity of the product by forming a through hole in the supply and recovery.

In the apparatus of the present invention for realizing this, in a state in which a plurality of copper foil sheet supply rollers 11 in which the copper foil sheet 1 is wound in a roll form is configured, the copper foil sheet 1 wound around each constitutes a plurality of layers. A supply unit 10 which is continuously stacked and supplied; A drilling machine unit 20 in which a plurality of drills 21 are installed to mechanically elevate a hole for forming a via hole in the copper foil sheet 1 that is laminated and supplied from the supply unit 10 and penetrate it; A pressure roller (30) for pressurizing and guiding the plurality of copper sheet (1) supplied and discharged to the drilling machine part (20) to maintain a state of being in close contact with each other; And a recovery part 40 configured with a plurality of copper foil sheet recovery rollers 41 such that the copper foil sheet 1 discharged from the drilling machine part 20 is rolled up in a roll form, respectively. .

Duplex, Flexible, Printed Board, FPCB, Manufacturing, Roll to Roll, Mechanical Drill

Description

A via hole forming apparatus and method for a double-sided flexible printed board using a mechanical drilling machine {ROLL TO ROLL FORM MANUFACTURE METHODE OF FLEXIBLE PRINTED CIRCUIT BOARD USING MECHANICAL TYPE DRILL}

1 is a process chart showing a conventional FPCB manufacturing process.

Figure 2 is a process diagram showing a conventional roll-to-roll method of manufacturing FPCB.

3 is a schematic configuration diagram of an apparatus for a mechanical drill operation of the present invention.

4 is an enlarged view of a portion A of FIG. 3;

<Explanation of symbols for the main parts of the drawings>

1: Copper foil sheet 2,2 ': Resin film

10: supply part 11: supply roller

12: Entry roller 13: Backup roller

20: drilling machine part 21: drill

22: base unit 30: pressurized roller

40: recovery part 41: recovery roller

42: entry roller 43: backup roller

The present invention relates to the manufacture of flexible printed circuit boards, and more particularly, in the manufacture of double-sided flexible printed circuit boards each having circuits formed on both sides, through the production of laminated copper foil sheets by forming via holes using a mechanical drilling machine. It is to increase productivity.

In general, with the development of electronic components and component embedding technology, printed circuit boards overlapping circuit conductors have been continuously developed.

Recently, in the field of electronics industry, the rapid development of integrated density of semiconductor integrated circuits and the surface mount technology for directly mounting small chip components have been developed and the electronic equipments have been miniaturized. Therefore, it is necessary to facilitate the installation in more complicated and narrow spaces. In order to meet these demands, fine circuit double-sided and flexible multilayer printed circuit boards have been developed.

In particular, in the case of high-use, flexible double-sided flexible printed circuit boards (FPCBs), demand for mobile phones, DVDs, digital cameras, PDPs, etc. has increased dramatically due to technological developments. I'm going.

In general, the manufacturing process of the flexible printed circuit board (FPCB) is a CNC hole processing of the raw material of the copper foil after setting the position, electroless plating and electroplating in the through-hole, dry film laminating, exposure, development, etc. The process forms a circuit.

That is, the manufacturing process of the conventional FPCB through the flow chart of Figure 1, first, the sheet (Sheet) of a flexible copper foil laminated plate (generally laminated to 18㎛ copper foil on a 25㎛ polyimide film) forming a copper foil layer on the upper and lower surfaces Cut through the copper foil sheet to form a through hole for electrical connection by using a through-drill, and electroless copper plating is performed to a thickness of 0.5㎛ over the entire surface of the copper foil sheet, and on the formed electroless copper plating layer The electroplating is performed to a thickness of 10 μm so that the electroplating layer is formed over the entire surface of the substrate including the through hole.

Then, after performing the front (substrate cleaning) process, the dry film is laminated, and the exposure process using ultraviolet light (UV light), the developing process using a developer, the etching process using an etching solution, and the dry film remaining on the substrate surface are peeled off. By performing the peeling process, a circuit is formed on both sides of the substrate, and a temporary process of temporarily bonding the coverlay to both sides is performed.

However, in the case of the conventional FPCB manufactured through such a process, productivity is reduced because each process is performed in the state of cutting in the form of a sheet. Especially, in the case of thin thin products, the product is caught or wrinkled while being transported for each process. There was a problem that a defect occurred.

In addition, looking at the manufacturing process of the double-sided FPCB roll-to-roll method is generally applied through the flow chart of Figure 2, in the middle of feeding the raw material of the rolled polyimide copper foil sheet in the feed roller to the recovery roller side A via hole is formed by using a UV laser drill, and the via hole is formed and the copper foil sheet wound on the recovery roller is supplied to the recovery roller while the copper sheet is wound on the supply roller. Soft etching or brush polishing or Z scrubber is used. Electrolytic plating to clean the surface and inside the hole, and electroless plating on both sides of the copper foil sheet in the same way, and to form an electroplated layer on both sides of the electroless copper plating where the electroless plating layer is formed on both sides. Process, rolled copper foil sheet with electroplated layers formed on both sides The laminating process of laminating photosensitive dry film on both sides, the exposure process of partially laminating the UV film according to the circuit pattern on the dry film surface by passing the laminated copper foil sheet through a continuous exposure machine, and the roll state of UV exposure The development process in which the dry film portion which was not exposed to the copper foil sheet using the developer was removed, and the copper foil sheet in which the development process was performed was passed through the etching solution to remove the dry film, and the copper foil layer of the developing region exposed to the outside was exposed to the etching solution. The FPCB sheet in the rolled state wound on the recovery roller through an etching process to be removed by a dry film and then a dry film peeling process to peel off the dry film remaining on the copper foil layer forming the circuit pattern in the process of continuously proceeding the copper foil sheet. Is a continuous circuit pattern on both sides Performing been cut into sheet form of a bar, according to each area, and performs the post-processing tasks such as process kabareyi attachment operation for each of the FPCB sheet is cut is made.

However, in the conventional roll-to-roll method, since the UV laser drill is used to form the via hole, productivity is significantly reduced because the drill work is performed one by one without overlapping the copper foil sheets. Due to winding and winding through, there was a problem that the productivity is reduced and the lead time is long.

The present invention has been proposed to improve the above-described problems in the prior art, and in forming a via hole in the manufacturing process of a flexible circuit board made of a copper foil sheet, a plurality of copper foil sheets are superimposed on a mechanical drilling machine. The aim is to greatly improve productivity.

Hereinafter, a specific embodiment of the present invention for achieving the above object will be described with reference to FIGS. 3 and 4.

3 is a structural view showing a schematic configuration of a roll-to-roll type via hole forming apparatus according to the present embodiment, and FIG. 4 is an enlarged view of a portion A of an enlarged cross-sectional structure of a copper foil sheet laminated and supplied in a roll-to-roll manner.

First, looking at the configuration of the roll-to-roll via-hole forming apparatus of the flexible printed circuit board according to the present embodiment through Figure 3, in the state that the six copper foil sheet supply rollers 11 in which the copper foil sheet 1 is wound in a roll form A via hole (not shown) is provided in the supply part 10 in which the copper foil sheets 1 wound on each are laminated in a plurality of layers, and the copper foil sheets 1 are laminated and supplied from the supply part 10. Drilling machine part 20 is provided with a plurality of drills 21 for mechanically lifting and forming the hole for forming, and a plurality of copper sheet (1) in the position supplied and discharged to the drilling machine 20 6) copper foil sheets such that the pressure roller 30 for guiding the pressure rollers to maintain the state of closely contacting each other and the copper foil sheet 1 discharged from the drilling machine unit 20 are rolled up in a roll form. Ash recovery roller 41 It comprises a portion (40).

In particular, the upper end and the lower end of the laminated copper foil sheet 1 supplied to the drilling machine part 20 in a state in which the flexible resin films 2 and 2 ′ having a predetermined thickness are wound on the supply part 10 and the recovery part 40. Entry rollers 12 and 42 and backup rollers 13 and 43 for supplying the resin films 2 and 2 'at the same time are respectively installed. The backup rollers 13 and 43 as shown in the cross-sectional view of FIG. ), The thickness d of the lower resin film 2 'wound up to 0.5 mm is used, and a material thicker than 0.25 mm, which is the thickness D of the upper resin film 2 wound around the entry rollers 12, 42, is used. desirable.

The reason for supplying the flexible resin film 2, 2 'together is that the upper resin film 2, which is supplied and recovered through the entry rollers 13, 43, has a burr on the upper surface of the copper foil sheet 1 during drilling. (Burr) is to prevent the occurrence, and the lower resin film (2 ') supplied and recovered through the back-up rollers (12, 42) to be completely drilled to the bottom copper foil sheet (1) Is to.

On the other hand, the drilling machine unit 20 is provided with a base unit 22 for supporting the drilling process from the bottom and to transfer the copper-clad laminated sheet as much as the given data, the drill 21 for penetrating the via hole to position alignment It is mounted so as to be movable up and down by a left and right movement and a cylinder, etc., the structure for the operation of the drill 21 is a conventional configuration, so a detailed configuration description will be omitted.

The roll-to-roll continuous manufacturing process of the flexible printed circuit board using the present invention via hole forming device having such a configuration will be described.

First, the supply roller 11 in which the polyimide copper foil sheet 1 is wound in a roll state, which is a raw material of a flexible printed circuit board, is superimposed on the supply part 10 to set the drill amount.

At this time, the supply unit 10 is mounted with the copper foil sheet supply roller 11, the entry roller 12, and the backup roller 13, the resin film (2, 2 ') is wound together.

In addition, the recovery unit 40 has a recovery roller 41, an entry roller 42, and a backup roller for rewinding the sheet mill film supplied from the rollers 11, 12, and 13 to maintain a constant tension. 43) to be mounted.

In this way, when the supply power is applied in a state in which each roller setting is completed, the copper foil sheet 1 is released from each supply roller 11 and supplied to the drilling machine part 20 in a state of being laminated in a plurality of layers. Will be.

At this time, the upper and lower portions of the copper foil sheet 1, which is supplied in a plurality of layers, as shown in the cross-sectional view of FIG. 4, the resin films 2 and 2 'supplied from the entry roller 12 and the backup roller 13, respectively. ) Is supplied together to reduce the burrs generated on the upper surface side during the drilling process, and can be completely processed to the copper foil sheet of the bottom layer.

On the other hand, in the drilling machine unit 20 while the spindle drill 21 performs the drilling operation according to the given data from the control unit (not shown), the process of being conveyed by the base unit 22 by the given distance is repeatedly performed The work to be recovered to the recovery unit 40 side is made continuously.

Therefore, as in the present invention by manufacturing a substrate using a mechanical drill in a multi-layer laminated state in a roll-to-roll method, compared to the technique of forming the through-hole in the individual layer using a conventional UV laser drill workability and Productivity will be greatly improved.

Then, when the through-hole forming process for penetrating the via hole and the work reference hole formed on the surface of the copper foil sheet 1 laminated through the roll-to-roll operation is completed, the recovery hole 41 is formed in the via hole. After mounting the wound copper foil sheet (1) to a new supply roller, the post-processing processes such as plating process, exposure process, peeling process and cutting process for circuit formation are performed by roll-to-roll method, so that continuous production of FPCB substrate is possible. It can be seen that it can be made.

As described above, the present invention, in the manufacture of a flexible printed circuit board, the copper foil sheet as a plurality of layers to overlap the mechanical drilling machine by forming a through-hole in the supply and recovery in a roll-to-roll method of the transfer of the thin sheet sheet determined It is a useful invention that can improve the productivity of the product by preventing the wrinkles in the process, and also allows the formation of the through-hole at a time in the state of being laminated in multiple layers.                     

In particular, in order to prevent defects that may occur during stacking, the flexible resin film may be supplied together at the bottom and bottom of the copper foil sheet, thereby minimizing mechanical troubles, thereby maximizing quality.

Claims (4)

Supply part 10 in which a plurality of copper foil sheet feed rollers 11, in which the copper foil sheet 1 is wound in a roll shape, is continuously stacked and supplied in a plurality of layers. ), And a drilling machine part 20 in which a plurality of drills 21 are formed to mechanically elevate and move holes for forming a via hole in the copper foil sheet 1 laminated and supplied from the supply part 10, and Pressure roller 30 for guiding and pressing the plurality of copper sheet 1 to be supplied and discharged to the drilling machine unit 20 to maintain a state in close contact with each other, and discharged from the drilling machine unit 20 Comprising the copper foil sheet (1) to be rolled up each roll form a plurality of copper foil sheet recovery roller 41 is configured to include a configuration comprising a, 40, The supply part 10 and the recovery part 40 simultaneously have an upper end and a lower end of the laminated copper foil sheet 1 supplied to the drilling machine part 20 while the flexible resin films 2 and 2 ′ having a predetermined thickness are wound. An entry roller (12, 42) and a backup roller (13, 43) for supplying the resin film (2, 2 ') via hole forming apparatus of a double-sided flexible printed board using a mechanical drilling machine, characterized in that each configured. delete The method according to claim 1, The flexible resin film 2, 2 ′ has a thickness d of the resin film 2 ′ wound on the entry rollers 13, 43 and the thickness of the resin film 2 wound on the backup rollers 12, 42. A via hole forming apparatus for a double-sided flexible printed circuit board using a mechanical drilling machine, characterized in that it is thicker than (D). A via hole is formed in the copper foil sheet supplied in a roll state, and a process of washing, forming an electroless plating layer, and forming an electrolytic plating layer is performed sequentially, and a circuit is formed on both sides of the sheet through dry film laminating, exposure, developing, etching, and peeling steps. In the manufacturing process of the flexible printed circuit board to be supplied and recovered in a roll-to-roll state at each step until the forming process In the process of forming the via hole, a roll-to-roll method of supplying a plurality of copper foil sheets is stacked, and a supply of a resin film having a predetermined thickness is provided on the upper and lower portions of the copper foil sheet to be supplied. ; The via-hole forming method of the double-sided flexible printed circuit board using a mechanical drilling machine, characterized in that for the supplied laminated copper foil sheet to form a through hole using a mechanical drill.

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