JPH0695137A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To eliminate the influence of static electricity in production process and distribution process and to provide the liquid crystal display element having stable quality by coating the parts which are terminal parts exclusive of the connecting parts of electrode terminals and connecting terminals and are exposed to the outside with an insulator. CONSTITUTION:The liquid crystal display panel 31 is constituted by injecting a liquid crystal layer 36 between a pair of light transparent substrates 32 and 33 having transparent electrodes 34, 35 on the surfaces and sealing the substrates with a sealing material 37. The electrode terminal parts 51 exclusive of the connecting part of the liquid crystal display panel 31 and a flexible wiring board 40 and the connecting part 52 of the wiring board 40 and PWB 47 packaged with an integrated circuit chip are coated with coating tapes 41. The coating tapes 49 consist of a synthetic resin, such as vinyl chloride, having an insulating characteristic and are stuck to the prescribed parts by an adhesive 50, such as acrylic resin. The breakdown of the driving circuit chip 39 by electrification of the exposed parts 51, 52 with static electricity is prevented according to such constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a word processor, a personal computer, an electronic notebook, an electronic game, etc.
The present invention relates to a liquid crystal display device used as a display device for various electronic devices, and more particularly to a liquid crystal display device using a tape carrier package (TCP) for connecting a drive circuit chip to a liquid crystal display panel.

[0002]

2. Description of the Related Art In a liquid crystal display panel, a liquid crystal element is formed by interposing a liquid crystal between a pair of translucent substrates each having a transparent electrode and an alignment film formed on opposite surfaces, and a pair of polarizing plates. It is arranged in between. The liquid crystal display panel applies a voltage from the outside to the transparent electrode to control the alignment state of liquid crystal molecules, and utilizes the change in the optical characteristics of the liquid crystal to perform display. Since such a liquid crystal display panel can have a smaller depth and consume less power than a cathode ray tube or the like, it is widely used especially in a portable word processor and other electronic devices.

The liquid crystal display panel used in the above-mentioned electronic equipment is connected to the TCP in consideration of the recent demand for further thinning, durability, and reliability of the connection portion with the drive circuit chip. The TCP method is widespread.

FIG. 3 is a sectional view showing the structure of a conventional liquid crystal display device of the TCP system. The liquid crystal display panel 1 is
A pair of translucent substrates 2 and 3 made of glass, plastic, or the like are arranged so as to face each other, and a plurality of strip-shaped transparent electrodes 4 made of ITO (indium tin oxide) or the like are provided on the surfaces of the substrates 2 and 3 which face each other. , 5 are respectively formed, the liquid crystal layer 6 is injected between the substrates, and sealed with a seal material 7. Note that, in FIG. 3, an alignment film, a polarizing plate and the like are omitted.

The liquid crystal display panel 1 has a strip-shaped transparent electrode 4,
Reference numeral 5 is a simple matrix type liquid crystal display panel configured to be orthogonal to each other. In order to apply a drive voltage to each of the transparent electrodes 4 and 5, it is necessary to form an electrode terminal that connects a drive circuit that supplies the drive voltage.

In the liquid crystal display panel 1, the electrode terminals 8 are formed by extending any one of the longitudinal directions of the strip-shaped transparent electrodes 4 and 5 to the vicinity of the peripheral portions of the substrates 2 and 3. Hereinafter, description will be made in relation to the substrate 2,
The same applies to the substrate 3.

One side of a flexible wiring board (TCP; referred to as "tape carrier package") 10 on which a drive circuit chip 9 for supplying a drive voltage to the transparent electrode 4 is mounted on the electrode terminal 8. The connection terminal 11 formed in the above is electrically connected through the anisotropic conductive film 12.

The connection terminal 13 formed on the other side of the wiring board 10 is formed by a terminal 15 and a solder 16 formed on a PWB (Printed Wiring Board) 17 on which another integrated circuit chip (not shown) is mounted. It is electrically connected.

A light-shielding tape 19 is attached to the surface of the drive circuit chip 9. The light shielding tape 19 is made of a synthetic resin having a light shielding property and an insulating property such as vinyl chloride, and is formed in a flat tape shape or a film shape. The light shielding tape 19 is attached by an adhesive 20 made of an adhesive synthetic resin such as acrylic.

When the drive circuit chip 9 is irradiated with light, a photoelectromotive force is generated, whereby a DC voltage is applied to the liquid crystal display panel 1, and a screen of the liquid crystal display panel 1 controlled by each of the plurality of drive circuit chips. Each time, there is a problem that shading occurs. In order to solve this problem, the above-mentioned light shielding tape 19 is attached. Such a technique is disclosed in JP-A-4-14023.

[0011]

At present, for the purpose of providing electronic devices with a characteristic of thinning, a so-called intermediate finished product, in which a PWB is connected to the above-mentioned liquid crystal display device of the TCP system, is provided. The form that is shipped from the factory and directly installed in the electronic device cabinet by the user,
More often than not.

In the above-mentioned conventional liquid crystal display device, the electrode terminal portion 21 other than the connecting portion between the liquid crystal display panel 1 and the wiring board 10 and the connecting portion 22 between the wiring board 10 and the PWB 17 are exposed. .

Therefore, when touched by various machines or human fingers used in the manufacturing stage of the liquid crystal display device, or handled by the user in the process of the above-described shipping form, the device is driven by static electricity and driven. There is a problem that the internal circuit of the circuit chip 9 is destroyed.

An object of the present invention is to provide a liquid crystal display device capable of preventing the internal circuit of the drive circuit chip from being destroyed by the influence of static electricity generated at the manufacturing stage of the liquid crystal display device and the handling stage of the user with a relatively simple structure. Is to provide.

[0015]

SUMMARY OF THE INVENTION The present invention is formed on a flexible substrate on which electrode terminals formed on a substrate constituting a liquid crystal display panel and a drive circuit chip for driving the liquid crystal display panel are mounted. In the liquid crystal display device formed by connecting the connection terminals, the terminal portions other than the connection portions between the electrode terminals and the connection terminals, which are exposed to the outside, are covered with an insulator. A characteristic liquid crystal display device.

[0016]

According to the present invention, the terminals other than the connecting portion between the liquid crystal display panel and the flexible wiring board, which are exposed to the outside, are covered with an insulating material. Therefore,
It is possible to prevent static electricity from falling to the exposed portion when touched by a human finger, a work machine, or the like, and it is possible to prevent destruction of the internal circuit of the drive circuit chip.

[0017]

1 is a sectional view showing the structure of a TCP type liquid crystal display device according to the present invention, and FIG. 2 is a plan view of the liquid crystal display device.

In the liquid crystal display panel 31, a pair of translucent substrates 32 and 33 made of glass, plastic or the like are arranged so as to face each other, and ITO is provided on the surfaces of the substrates 32 and 33 which face each other.
A plurality of transparent electrodes 3 made of (indium tin oxide) or the like
4, 35 are respectively formed, the liquid crystal layer 36 is injected between the substrates, and the liquid crystal layer 36 is sealed with a sealing material 37. Note that, in FIG. 1, an alignment film, a polarizing plate and the like are omitted.

The liquid crystal display panel 31 is a simple matrix type liquid crystal display panel in which, for example, band-shaped transparent electrodes 34 and 35 are formed so as to be orthogonal to each other. Each transparent electrode 3
In order to apply the drive voltage to each of the electrodes 4 and 35, it is necessary to form an electrode terminal for connecting a drive circuit that supplies the drive voltage.

In the liquid crystal display panel 31, one of the longitudinal directions of the strip-shaped transparent electrodes 34, 35 is set to the substrate 3
The electrode terminals 38 are formed by forming the electrode terminals 38 by extending them to the vicinity of the peripheral portions of the electrodes 2, 33. Hereinafter, the substrate 32 will be described, but the same applies to the substrate 33.

A flexible wiring board (TCP; tape carrier package) 40 on which a drive circuit chip 39 for supplying a drive voltage to the transparent electrode 34 is mounted on the electrode terminal 38,
The connection terminal 41 formed on one side has an anisotropic conductive film 42.
Is electrically connected via.

The connection terminal 43 formed on the other side of the flexible wiring board 40 is electrically connected to the terminal 45 formed on the PWB 47 on which another integrated circuit chip (not shown) is mounted by using solder 46. Connected to.

As shown in FIGS. 1 and 2, the electrode terminal portion 51 other than the connecting portion between the liquid crystal display panel 31 and the flexible wiring board 40, and the flexible wiring board 40 and the PWB 47.
The connecting portion 52 with is covered with a covering tape 49. The covering tape 49 is made of an insulating synthetic resin such as vinyl chloride, and is formed in a flat tape shape or a film shape. The covering tape 49 is attached by an adhesive 50 made of an adhesive synthetic resin such as acrylic. The covering tape 49 may be easily peelable from the drive circuit chip 39 or the like, or may be firmly adhered so as not to peel off.

As described above, according to this embodiment, in the liquid crystal display device, the electrode terminal portion 5 exposed to the outside is provided.
Since the 1 and the connecting portion 52 are respectively covered with the covering tape 49, static electricity is charged on the exposed portions 51 and 52 by touching the liquid crystal display device with various machines and human fingers used in the manufacturing stage. This can be prevented, and the internal circuit of the drive circuit chip 39 can be prevented from being destroyed.

There is a case where a new shipping form is carried out in which an intermediate finished product such as the liquid crystal display panel 31 shown in FIG. 1 is shipped from a factory and directly assembled by a user into a cabinet of electronic equipment. Even in such a shipping form, it is possible to prevent the internal circuit of the drive circuit chip 39 from being destroyed by being charged with static electricity when touched by the user's hand.

Further, the covering tape 49 and the adhesive 5
0 is the drive circuit chip 9 in the prior art shown in FIG.
Shading tape 19 and adhesive 2 attached to the surface of
It is the same as 0. Therefore, it is not necessary to manufacture a new dedicated tape for covering, and the conventionally used light-shielding tape can be used, which can be realized at low cost.

As a result, the covering tape 49 has a problem caused by the irradiation of the drive circuit chip 39 with light, that is, the drive circuit chip 39 is irradiated with light to generate a photoelectromotive force, which causes the liquid crystal display panel 31 to have a photoelectromotive force. It is possible to simultaneously solve the problem that light and shade occur in each screen of the liquid crystal display panel 31 to which a DC voltage is applied and which is controlled by a plurality of drive circuit chips.

As another coating method, both exposed portions 51, 5
In No. 2, there is a method of applying an electrically insulating resin. However, with this coating method, the thickness of the resin applied to both exposed portions 51 and 52 becomes uneven. This is because, for example, when the liquid crystal display panel 31 is incorporated into a cabinet to assemble the device, if a surface including a resin-coated portion of the wiring board 40 is pressed and fixed using a cushioning material such as silicon rubber, the pressure will be reduced. It becomes non-uniform and causes damage to the liquid crystal display panel 31 and the connecting portion.

In addition, the flexible wiring board 40 may be replaced at present for maintenance service to the user. In such a case, when the exposed portions 51 and 52 are covered with resin, there is a problem in the work such that the work of taking the resin is troublesome or the resin cannot be sufficiently taken out.

However, since the covering tape 49 can also be used as a light-shielding tape stuck on the drive circuit chip 39 which has been conventionally used, it is possible to prevent the problem that the liquid crystal display device is broken due to the uneven thickness.

Further, since the covering tape 49 may be easily peeled off as described above, it is superior to the method of applying the electrically insulating resin also in the work such as the replacement of the flexible wiring board 40.

Although a simple matrix type liquid crystal display panel has been described in this embodiment, it may be applied to a segment type or active matrix type liquid crystal display panel.

In this embodiment, one cover tape 4 is used.
9 was attached so as to cover the entire surface of the wiring board 40, but the exposed portions 51, 5 were formed by using three covering tapes 49.
2 and the peripheral portion of the drive circuit chip 39 may be covered. Also, if you focus only on measures against static electricity,
The covering tape 49 may not be attached to the drive circuit chip 39.

[0034]

As described above, according to the present invention, the terminal portion other than the connecting portion between the electrode terminal and the connecting terminal in the liquid crystal display device, which is exposed to the outside, is covered with the insulator. Therefore, the influence of static electricity in the manufacturing process and the distribution process can be prevented. This makes it possible to supply a liquid crystal display device having stable quality.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a liquid crystal display device which is an embodiment of the present invention.

FIG. 2 is a plan view of a liquid crystal display device which is an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a conventional liquid crystal display panel 1.

[Explanation of symbols]

 31 liquid crystal display panel 32, 33 translucent substrate 38 electrode terminal 39 drive circuit chip 40 flexible wiring substrate 41, 43 connection terminal 42 anisotropic conductive film 47 PWB 49 coating tape 50 adhesive 51, 52 exposed to the outside Electrode part

Claims (1)

[Claims] 1. An electrode terminal formed on a substrate that constitutes a liquid crystal display panel and a connection terminal formed on a flexible substrate on which a drive circuit chip for driving the liquid crystal display panel is mounted are connected. In the liquid crystal display device having the above structure, the terminal portion other than the connection portion between the electrode terminal and the connection terminal, which is exposed to the outside, is covered with an insulating material.