CN101887182B

CN101887182B - Method for connecting flexible printed circuit board with liquid crystal display step surface

Info

Publication number: CN101887182B
Application number: CN2010102138408A
Authority: CN
Inventors: 杨顺林; 李江; 王旭
Original assignee: Shenzhen Success Electronic Co Ltd
Current assignee: Shenzhen Success Electronic Co Ltd
Priority date: 2010-06-30
Filing date: 2010-06-30
Publication date: 2012-07-04
Anticipated expiration: 2030-06-30
Also published as: CN101887182A

Abstract

The invention discloses a method for connecting a flexible printed circuit board with a liquid crystal display step surface. An exposed golden finger part contacted with an edge of the LCD step surface is covered and protected by a PI layer. The method comprises the steps that: 1, a part of the PI layer covering layer is increased on the golden finger of the LCD step surface; 2, the LCD design requires that a blank space is reserved between an ITO pin of the LCD and the edge of the LCD step surface; and 3, the FPC and the LCD alignment requires that when a lateral mark of the FPC golden finger is aligned, the width of the FPC PI layer stretches into the LCD is narrower than that of the reserved blank space of the LCD. The connecting method is applied to the process of manufacturing LCD panels.

Description

The method of attachment of a kind of flexible printed circuit board and liquid crystal display step surface

Technical field

The present invention relates to P.e.c. interconnection technique field, the method for attachment of particularly a kind of flexible printed circuit board and liquid crystal display step surface.

Background technology

In electronic installation in recent years; Flexible printed circuit board (FPC) is widely used in being mounted in the portable information apparatus, and the main representative of these portable electric appts has DVC (DV), mobile phone, PDA (personal digital assistant), digital camera, notebook computer etc.

FPC is the important component part of liquid crystal display, and at first it not only plays the effect that is connected with LCD (LCD) internal circuit, and is the bridge that is connected with the equipment peripheral circuit.But in the process of making liquid crystal panel, the golden finger of FPC and LCD junction part fractures easily, causes liquid crystal display to occur not showing that bad phenomenon such as mess code influence huge.

Present great majority design is as shown in Figure 1; The FPC of this kind design presses the LCD step surface after FOG (FPC and LCD nation are fixed) hot pressing golden finger does not partly have PI (polyimide film) layer to cover; Make and exposing, cause that in FPC bending process the FPC golden finger fractures near the FPC of LCD edge golden finger 2.

The reason that causes the FPC golden finger to fracture mainly contains the following aspects:

(1) after the hot pressing, the FPC golden finger exposes, not anti-bending.

(2) FPC material problem.

(3) one line glue strengthening actions are little, cause after the bending when client installs to fracture.

Way to these domestic several companies of problem is as shown in table 1:

Table 1

The above way of this area is to improving the FPC golden finger certain effect that fractureed, but not enough system is thorough, and this problem is not eliminated in these measures fully.

Summary of the invention

The objective of the invention is to overcome the shortcoming of prior art, the method for attachment of a kind of flexible printed circuit board and liquid crystal display step surface is provided.

The present invention proposes the complete scheme of a cover, carry out system design from several aspects such as LCD design specifications, FPC PI layer cover width, FPC aligning accuracy respectively.

The former exposed golden finger that is connected with the LCD step surface is partly carried out covering protection with the PI layer.Method: LCD design LCD leaves the clear area in the edge; The golden finger of FPC and step surface edge contact covers with the PI layer.

The method of attachment of a kind of flexible printed circuit board and liquid crystal display step surface, its step is following:

Step 1 is at the golden finger increase part PI (polyimide film) of LCD step surface layer overlayer;

Step 2, its ITO of LCD designing requirement (Indium Tin Oxid, indium tin oxide conductive film) pin distance L CD step surface edge leaves the clear area;

Require when step 3, the contraposition of FPC and LCD: when FPC golden finger slogan banner on time, the FPCPI layer stretches into the width distance of LCD, reserves the clear area less than its LCD.

Said LCD step surface edge leaves the clear area and is designed to more than or equal to 0.2mm, smaller or equal to 0.4mm.

Clear area, said LCD step surface edge width is designed to 0.3mm the best.

The width distance that said FPC PI layer (1) stretches into LCD is more than or equal to 0.1mm, smaller or equal to 0.3mm.

Said width distance equals 0.2mm for best.

Said LCD reserves the clear area and equals 0.3mm.

The FPC aligning accuracy need guarantee to be ± 0.1mm.

Beneficial effect of the present invention

The present invention proposes a kind of system and eliminates the method that FPC golden finger hot pressing end fractures comprehensively; Carry out FOG according to normal operation, how to bend the FPC golden finger and also can not fracture, thereby effectively avoid not showing because of the golden finger liquid crystal panel that causes that fractures; Mess code such as lack to draw at bad phenomenon.

Kind of design	Quantity	The bending number of times	Quantity fractures
				Former design	200	50 times	9PCS
The invention design	187	50 times	0PCS

Table 2

According to the present invention program; FPC PI is introduced the LCD step surface, and make relevant measure, finally can effectively prevent fractureing of FPC golden finger for reaching this purpose; Thereby eliminate because of the FPC golden finger fracture and cause bad, specifically as shown in table 2 to the product result that makes an experiment.

Utilize the present invention program simultaneously, with the edging operation of cancellation LCD before pressing FPC, the result who does cripping test after the product ordinary production of cancellation edging is as shown in table 3:

Table 3

Show from the test findings of table 3, adopt the present invention program can cancel edging operation, practice thrift simultaneously because of costs such as the related manpower of edging, material, part, man-hour, places.

The present invention is applicable to the liquid crystal panel manufacture process.

Description of drawings

Fig. 1 is the FPC of prior art and the method for attachment synoptic diagram of LCD.

Fig. 2 is FPC of the present invention and LCD step surface method of attachment synoptic diagram.

Fig. 3 is the method for attachment synoptic diagram of flexible printed circuit board of the present invention and liquid crystal display step surface.

Embodiment

As shown in Figure 1, the 1st, (FPC PI layer), the 2nd, golden finger, 3 be 1 with the clearance distance of LCD.The golden finger of LCD step surface does not partly have PI (polyimide film) layer to cover, and makes and is exposing near the FPC of LCD edge golden finger 2, causes that in FPC bending process the FPC golden finger fractures.

As shown in Figure 2, the 4th, the clear area at LCDITO (indium tin oxide conductive film) pin distance L CD step surface edge;

The method of attachment of flexible printed circuit board and liquid crystal display step surface, its step is following:

Step 1 is at golden finger 2 increase part PI (polyimide film) layers 1 overlayer of LCD step surface;

Step 2, its ITO of LCD designing requirement (indium tin oxide conductive film) pin distance L CD step surface edge leaves clear area 4, and LCD step surface edge leaves clear area 4 and is designed to more than or equal to 0.2mm, smaller or equal to 0.4mm.Clear area, LCD step surface edge width 4 is designed to 0.3mm the best, and design can guarantee that FPC golden finger PI layer is appeared on the stage and LCD is not affected with the electric conductivity that is connected of FPC behind the terrace like this.

As shown in Figure 3, the method for attachment of flexible printed circuit board and liquid crystal display step surface,

Require when step 3, the contraposition of FPC and LCD: when FPC golden finger 2 slogan banners on time, FPC PI layer 1 stretches into the width distance 6 of LCD 7 more than or equal to 0.1mm, smaller or equal to 0.3mm.The width distance 6 that FPC PI layer 1 stretches into LCD 7 equals 0.2mm for best, and LCD reserves clear area 8 and equals 0.3mm, and during contraposition, the FPC aligning accuracy need guarantee to be ± 0.1mm, to avoid causing short circuit problem.

In addition, if PI layer 1 covering precision has only 0.2mm, causing FPC PI layer 1 to introduce ITO pin 5 easily, cause short circuit, thereby influence the demolition effect of conductive gold spacer, is 0.1mm so need to improve the PI covering precision.Improve covering precision, reduced error range, control more effective.

The width distance 6 of introducing LCD step surface FPC PI layer 1 is designed to 0.2mm, and the FPC aligning accuracy need guarantee to be ± 0.1mm.

Just can effectively prevent the FPC golden finger problem that fractures according to above design.

Claims

1. the method for attachment of flexible printed circuit board and liquid crystal display step surface, its step is following:

Step 1 increases polyimide layer (1) overlayer on the part corresponding to the golden finger (2) of the flexible printed circuit board of liquid crystal display step surface;

Step 2, its ITO pin of LCD designing requirement leaves clear area (4) apart from the liquid crystal display step surface edge, and said clear area (4) are designed to more than or equal to 0.3mm, smaller or equal to 0.4mm;

Step 3; Require during the contraposition of flexible printed circuit board and LCD: when golden finger (2) slogan banner of flexible printed circuit board on time; The polyimide layer of flexible printed circuit board (1) stretches into the width distance (6) of LCD (7), less than the clear area (4) of LCD reservation;

The polyimide layer of said flexible printed circuit board (1) stretches into the width distance (6) of LCD (7) more than or equal to 0.1mm, smaller or equal to 0.3mm; The flexible printed circuit board aligning accuracy need guarantee to be ± 0.1mm.

2. the method for attachment of flexible printed circuit board according to claim 1 and liquid crystal display step surface is characterized in that, said width distance (6) equals 0.2mm for best.