KR20060064960A - Flexible printed circuit board, and display panel and display device having the same - Google Patents

Abstract

A flexible printed circuit board, a display panel having the same, and a display device are disclosed. The flexible printed circuit board includes first insulating board signal wires and a second insulating board. The signal wires are formed on the first insulating substrate and include pad portions having end portions rounded or polygonal processed. A second insulating substrate is formed on the first insulating substrate, and covers the signal lines so that the pad portions are exposed. Accordingly, the flexible circuit board including rounded or polygonal pad portions may be pressed against the pad portion of the signal line to prevent short circuit and corrosion of the metal wiring electrically connected to the flexible circuit board.

Description

FLEXIBLE PRINTED CIRCUIT BOARD, AND DISPLAY PANEL AND DISPLAY DEVICE HAVING THE SAME

1 is a configuration diagram illustrating a flexible printed circuit board according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a portion A shown in FIG. 1.

3 is a configuration diagram illustrating a flexible printed circuit board according to a second embodiment of the present invention.

4 is an enlarged view of a portion B shown in FIG. 3.

5 is a cross-sectional view illustrating a display panel including a flexible printed circuit board according to a third exemplary embodiment of the present invention.

6 is a cross-sectional view illustrating a display device including a display pattern according to a fourth exemplary embodiment of the present invention.

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

110: first insulating substrate 120: signal wiring

122: signal line 124: pad portion

130: second insulating substrate 100: flexible printed circuit board

300: display substrate 400: display panel                 

450: light source 500: storage container

600: display device

The present invention relates to a flexible printed circuit board, a display panel and a display device having the same, and more particularly, to a flexible printed circuit board, a display panel and a display device having a structure for preventing the disconnection of the signal metal wiring. .

In general, various electronic devices such as a mobile communication terminal, a digital camera, a notebook, a monitor, and the like include a display device for displaying an image in response to an image signal input from an external source.

Various types of display devices, for example, cathode-ray tube (CRT), liquid crystal display (LCD), plasma display panel (PDP), field radiation display device (Field) Emission Display (FED) and Electro Luminescence (EL).

Among these, a liquid crystal display (LCD) displays an image by using optical characteristics of a liquid crystal. Liquid crystal displays (LCDs) have the advantages of being thinner and lighter than other displays and operating at low power consumption and low driving voltage.

Conventional liquid crystal display (LCD) is a display panel for displaying an image using the liquid crystal transmittance of light (printed circuit board) and display for generating a drive signal for controlling the display panel to display the image And a flexible printed circuit board electrically connecting the panel and the printed circuit board to transmit driving signals to the display panel.

The flexible circuit board is formed by cutting a signal line having a long tape shape, that is, a base body on which metal wires are formed to a predetermined length. However, the cutting process has a problem that the cut surface of the end of the base body is uneven according to the cutting conditions, so that the pad portion of the metal wiring formed on the boundary surface of the body has an uneven end, that is, a sharp end.

Such a pad portion having a sharp end portion causes a problem in that the signal metal wiring of the display substrate is disconnected or corroded when pressed and electrically connected to the signal metal wiring of the display substrate.

Accordingly, an object of the present invention is to provide a flexible printed circuit board having a structure for preventing disconnection of the signal metal wires during the crimping process of the pad portion and the signal metal wires.

Another object of the present invention is to provide a display panel including the flexible circuit board.

Another object of the present invention is to provide a display device having the display panel.

The flexible printed circuit board according to the exemplary embodiment for achieving the object of the present invention has a configuration including a first substrate, signal wires, and a second substrate. The first substrate is an insulating substrate formed of polyimide resin. The signal lines are formed on the first substrate and include pad portions rounded or polygonally processed at ends thereof. Here, the pad portion is formed to be spaced apart from about 50 to 150㎛ from the end of the first substrate. The second substrate is formed on the first substrate to cover the signal wires so that the pad portions of the signal wires are exposed.

In accordance with another aspect of the present invention, a display panel includes a flexible printed circuit board and a display substrate. The flexible printed circuit board includes a first substrate, signal wires, and a second substrate. The first substrate is an insulating substrate formed of polyimide resin. The signal wires are formed on the first substrate and include pad portions having end portions rounded or polygonal processed. Here, the pad part is formed to be spaced apart from about 50 to 150㎛ from the end of the first substrate. The second substrate is formed on the first substrate so that the pad portions are exposed. The display substrate is electrically connected to the pad portion of the exposed signal wires and displays an image.

In accordance with another aspect of the present invention, a display device includes a display panel including a flexible printed circuit board and a display substrate, a light source, and a storage container. The flexible printed circuit board may include a first substrate, signal wires formed on the first substrate and having end portions rounded or polygonal, and formed on top of the first substrate and exposing the pad portions. And a second substrate covering the signal wires. The display substrate is electrically connected to the exposed pad portions and displays an image. The light source provides light to the display panel, and the storage container accommodates the display panel and the light source.

According to the flexible printed circuit board, the display panel having the same, and the display device, one end of the pad part included in the signal wires has a rounded or polygonal structure, so that the pad part is pressed against the signal wires of the display substrate. The problem that the signal wires of the display substrate are cut or corroded can be prevented in advance.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Example 1

1 is a block diagram illustrating a flexible printed circuit board according to a first embodiment of the present invention, and FIG. 2 is an enlarged view of a portion A shown in FIG. 1.

Referring to FIG. 1, the flexible printed circuit board 100 according to the first exemplary embodiment may include the first insulating substrate 110, the signal wires 120 including the pad part 124, and the second insulating substrate 130. It includes.

The first insulating substrate 110 is a substrate formed of a synthetic resin to have a flexible (flexible) property to be easily bent, and to have an electrical insulation. The first insulating substrate 110 is a lower substrate on which the signal wires 120 are formed. Examples of the synthetic resins include polyimide resins.                     

The signal wires 120 are metal wires formed on the first insulating substrate 110 and have a structure in which a plurality of signal wires 120 are formed in a parallel manner. In addition, the signal wires 120 may include signal lines 122 and pad parts 124. The signal wires 120 may be made of a metal having excellent electrical conductivity such as copper, copper alloy, aluminum, aluminum alloy, and the like.

As illustrated in FIG. 2, the pad part 124 is a portion that is pressed and connected to the metal wires of the display panel and has rounded ends. More specifically, the pad portion 124 is rounded to have a hemispherical end portion.

The process of rounding the pad portion 124 of the metal wiring will be described in detail. First, an etching mask is formed on the pad portion of the metal wiring formed on the first insulating substrate 110. The etching mask (not shown) has a structure in which the rounded pad portion has the same shape as that of the metal wiring, that is, the end portion is rounded. Subsequently, the pad portion of the metal wiring exposed to the etch mask is etched or wet etched to form a pad portion of the metal wiring rounded at its end. Thereafter, the etching mask is removed, and then the second insulating substrate is pressed to manufacture the flexible circuit board.

Since the end portion of the pad portion 124 has a hemispherical shape, the pad portion 124 disperses a force concentrated on a specific portion of the metal wires during the pressing process connected to the metal lines of the display panel after the pressing process. The metal wires are prevented from being disconnected and corroded.

In addition, the pad part 124 may be formed to be spaced apart from about 50 to 150 μm from the end of the first insulating substrate 110. More preferably, it is formed to be spaced apart by about 100㎛.

Like the first insulating substrate 110, the second insulating substrate 130 has a flexible (flexible) property to be easily bent and is made of synthetic resin to have electrical insulation. The second insulating substrate 130 is an upper substrate formed on the first substrate 110 on which the signal lines 120 are formed to insulate the signal lines 120 from the outside. In this case, the second insulating substrate 130 covers the signal wirings 120 formed on the upper surface of the first insulating substrate 100 to expose the pad portion 124 of the signal wirings 120.

Example 2

3 is a configuration diagram illustrating a flexible printed circuit board according to a second exemplary embodiment of the present invention, and FIG. 4 is an enlarged view of a portion B shown in FIG. 3. Since the flexible printed circuit board according to the second embodiment has the same configuration as the flexible printed circuit board of the first embodiment, duplicate description thereof will be omitted, and the same reference numerals and names are used for the same components. Let's do it.

The flexible printed circuit board 100 illustrated in FIG. 3 includes the first insulating substrate 110, the signal wirings 220 including the pad part 224, and the same as the flexible printed circuit board shown in the first embodiment. 2 includes an insulating substrate 130.

In this case, as shown in FIG. 4, the pad part 224 is a part that is pressed-connected to metal wires (not shown) of the display panel and has an end portion of which is polygonal. In detail, the pad part 224 has an end portion having a polygonal shape. End portions of the pad part 224 may have various shapes such as a triangular shape, a tetragonal shape, a pentagonal shape, and a hexagonal shape.

The process of performing polygonal processing on the pad portion 224 of the metal wiring will be described in detail. First, an etching mask is formed on the pad portion of the metal wiring formed on the first insulating substrate. The etching mask has the same shape as the metal wiring pad portion having a polygonal end portion. Subsequently, the pad portion of the metal wiring exposed to the etch mask is etched or wet etched to form a pad portion of the metal wiring whose end is polygonally treated.

Since the pad part 224 has a polygonal shape at its end, the pad part 224 may disperse a force concentrated on a specific portion of the metal wires during the pressing process connected to the metal wires of the display panel. Thereafter, the metal wires may be prevented from being disconnected and corroded.

In the present embodiment, it is preferable to further include an anti-oxidation film (not shown) for suppressing oxidation of the pad portions exposed by the second insulating substrate. The antioxidant film has, for example, a double film structure including a nickel thin film and a gold thin film or a single film structure of a tin thin film.

Example 3

5 is a cross-sectional view illustrating a display panel including a flexible printed circuit board according to a third exemplary embodiment of the present invention. Since the flexible printed circuit board shown in the third embodiment of the present invention has the same configuration as the flexible printed circuit board of the first embodiment described above, duplicate description thereof will be omitted, and like reference numerals refer to like elements. Use the name.

Referring to FIG. 5, the display panel 400 includes a flexible printed circuit board 100 and a display substrate 300. The display substrate 300 according to the present exemplary embodiment displays an image by using light and is electrically connected to the pad parts 120 included in the signal wire of the flexible printed circuit board 100. At this time, the end of the pad portion 120 is rounded so that the end of the pad portion 120 has a hemispherical shape. In addition, the pad portion 120 is formed to be spaced apart from about 50 to 150㎛ from the end of the first insulating substrate. Preferably it is formed spaced about 100㎛. The display substrate 300 according to the present exemplary embodiment includes, for example, a first substrate 310, a second substrate 320, and a liquid crystal layer 330.

The first substrate 310 includes a plurality of pixel electrodes arranged in a matrix form, thin film transistors (TFTs), and thin film transistors disposed at each pixel electrode to apply a driving voltage to each pixel electrode. Signal lines 312 for operating the respective TFTs.

The signal lines 312 according to the present embodiment extend to the edge of the first substrate 310, and are metal wires electrically connected to the pad portions of the signal wire 120 of the flexible printed circuit board 100.

The second substrate 320 is disposed to face the first substrate 310. The second substrate 320 is formed on a surface of the second substrate 320 that faces the pixel electrode formed on the first substrate 310, and is a transparent and conductive common electrode, where each pixel electrode faces each other. Disposed color filters. The color filters include a red color filter selectively passing red light of white light, a green color filter selectively passing green light of white light, and blue color filters selectively passing blue light of white light.

The liquid crystal layer 330 is interposed between the first substrate 310 and the second substrate 320 and rearranged by an electric field formed between the pixel electrode and the common electrode. The light transmittance of light generated by an external light generator (not shown) is controlled by the rearranged liquid crystal layer 230, and the light controlled by the liquid crystal layer 330 passes through the color filters to display an image. .

The display panel 400 according to the present exemplary embodiment further includes a printed circuit board (not shown) for generating a driving signal. The printed circuit board includes a driving circuit for processing an image signal, and the driving circuit converts an image signal input from the outside into a driving signal for controlling the thin film transistor TFT. In the present exemplary embodiment, the flexible printed circuit board 100 electrically connects the printed circuit board and the first substrate 310 to transmit driving signals generated from the printed circuit board to the first substrate 310.

 The display panel electrically connected to the rounded pad portion prevents disconnection and corrosion of the metal wire electrically connected to the pattern.

Example 4

6 is a cross-sectional view illustrating a display device including a display pattern according to a fourth exemplary embodiment of the present invention. Since the display panel according to the fourth exemplary embodiment of the present invention has the same configuration as the display panel of the third exemplary embodiment, duplicate description thereof will be omitted, and the same reference numerals and names will be used for the same components. do.

Referring to FIG. 6, the display device 600 includes a display panel 400, a light source 450, and a storage container 500. The light source 450 is disposed under the display panel 400, and generates light and provides the light to the display panel 400. The light source 450 may be a Cold Cathode Fluorescent Lamp (CCFL) having a low heat emission amount. The storage container 500 accommodates the display panel 400 and the light source 450 to protect the display panel 400 and the light source 450 from external impact.

According to the present invention, the ends of the pad portions of the signal lines have a rounded or polygonal structure, thereby preventing disconnection and corrosion of the metal wires that are press-connected with the pad portion. As a result, short circuits and corrosion of the metal wirings can be prevented, thereby reducing display quality of the image of the display device.

In the detailed description of the present invention described above with reference to the preferred embodiments of the present invention, those skilled in the art or those skilled in the art having ordinary skill in the art will be described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

Claims (7)

A first substrate; A plurality of signal lines formed on the first substrate and including pad portions having end portions rounded or polygonal processed; And And a second substrate formed on the first substrate, the second substrate exposing the pad portions while covering the plurality of signal wires. The flexible printed circuit board of claim 1, wherein the pad part has a hemispherical or polygonal end portion. The flexible printed circuit board of claim 1, wherein the pad part is spaced apart from an end of the first substrate by 50 μm to 150 μm. The flexible printed circuit board of claim 1, wherein the plurality of signal lines further comprise an anti-oxidation film formed on the pad part. The flexible printed circuit board of claim 4, wherein the anti-oxidation film has a double film structure consisting of a nickel thin film and a gold thin film. A flexible wire including signal wires formed on a first substrate and including pad portions rounded or polygonally processed, and a second substrate formed on the first substrate and covering the signal wires so that the pad portions are exposed. Printed circuit board; And And a display substrate electrically connected to the pad portion exposed by the second substrate and displaying an image. A flexible wire including signal wires formed on a first substrate and including pad portions rounded or polygonally processed, and a second substrate formed on the first substrate and covering the signal wires so that the pad portions are exposed. A display panel electrically connected to a printed circuit board and pads exposed by the second substrate, and including a display substrate displaying an image; A light source providing light to the display panel; And And a storage container accommodating the display panel and the light source.

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