JPS61147233A - Laminating method of polarizing plate - Google Patents

Abstract

PURPOSE:To improve the sticking precision during polarizing plate lamination and to prevent an air bubble from being mixed by positioning a polarizing plate on a positioning tool where a liquid-crystal display element is set and fixing an end part of a adhesive layer temporarily, and then sticking the polarizing plate continuously while moving a separator peeling plate. CONSTITUTION:One end of an adhesive tape is fixed to the separator peeling plate 21 and the polarizing plate 4 is set and positioned on a polarizing plate setting part 24 with a separator 11 up; and the adhesive tape 23 is adhered to an end part of the separator 11 and then the polarizing plate 4 is inverted by about 180 deg. to peel off the separator 11 partially. The liquid-crystal display element is set and positioned on a liquid-crystal display element setting part 26 and the separator peeling plate 21 is mounted on the base 25 of the positioning tool 22. An auxiliary tool 28 coupled with the base 25 of the positioning tool 22 is closed and the front end of the polarizing plate 4 is positioned abutting on the polarizing plate positioning part 29; and the adhesive layer of the polarizing plate 4 is fixed temporarily on the external surface of the substrate of the liquid crystal display element. The polarizing plate is laminated while the separator peeling plate 21 is moved relatively to the left of the positioning tool 22 to advance the peeling of the separator 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a liquid crystal display element, and particularly to a method C for laminating a polarizing plate that is attached to the surface of an element substrate.

A liquid crystal display element is formed by sealing liquid crystal between a pair of substrates that face each other with a predetermined distance therebetween. The inner surface C of each substrate is transparent.
Magnetic poles, alignment films, etc. are formed respectively, and the outer surface of each substrate is laminated with, for example, a transmissive polarizing plate is laminated on the outer surface of one substrate, and a reflective polarizing plate is laminated on the outer surface of the other substrate. An adhesive layer is formed by applying an adhesive to the laminated side of each of these polarizing plates, and lamination of two polarizing plates to a substrate is performed by bonding this adhesive layer to the outer surface of the substrate (from the two). This adhesive layer is protected by a separator, and during lamination, this separator is peeled off and bonding is performed.

Ru.

Such initial failures during lamination of polarizing plates can be broadly classified into the following three types.

(1) Poor bonding accuracy (2) Contamination of air bubbles (3) Contamination of foreign matter The present invention relates to improvement C of (11, (2)).

[Conventional technology]

Conventionally, when laminating polarizing plates, the separators of the polarizing plate were partially peeled off manually and temporarily attached to the substrate of the liquid crystal display element by visual inspection, and then the polarizing plate was removed using a roller or the like while continuing to peel off the separators by hand. The two boards were pressed together and pasted together.

FIG. 9C shows a procedure for laminating a polarizing plate by this conventional method ζ2. In the figure, 101 is a liquid crystal display element, 102 is a polarizing plate provided with a separator 105, and 104 and 105 are rollers for laminating the polarizing plate. When laminating the polarizing plate 102'a' on the outer surface of the glass substrate 106 of the liquid crystal display element 101, peel off only the edge fz of the separator 105 to expose the entire adhesive layer, and apply θ to the polarizing plate 105' and the substrate.
The exposed adhesive layer at the tip is temporarily attached to the outer surface of the substrate 106 by hand, and the liquid crystal display element 101 is moved to the right as shown by the arrow and is caught between the rollers 1, 4, and 105, and laminated. In this case, the liquid crystal display element 101
As the separator 103 moves, the separator 103 is moved considerably to the left as shown by the arrow with respect to the substrate 106, thereby laminating while progressing the peeling.

[Problems to be Solved by the Invention] When a polarizing plate is laminated by the conventional method as described above, there are the following various drawbacks.

(1) Since the polarizing plate is temporarily attached visually, the alignment accuracy with respect to the substrate, that is, the bonding accuracy is poor.

(2) Since the separator is held by hand, it is necessary to widen the separation range X of the separator during temporary fixing (about 1/3 of the total length in the bonding direction), so that the adhesive layer Air bubbles often get mixed in when the outer surface of the board comes into contact with two or more places.Also, this air bubbles get mixed in when the polarizing plate is temporarily fastened in a wavy manner at the part A on the opposite side from the tip of the polarizing plate during temporary fastening. C: It increases.

[Means for solving problems]

An object of the present invention is to provide a method for laminating polarizing plates that can solve the above-mentioned problems. In the method for manufacturing a liquid crystal display device, the liquid crystal display device includes a liquid crystal that is made of liquid crystal, and a pair of polarizing plates that are respectively laminated on the outer surfaces of the two substrates.
=, Separator peeling plate 2. Affix the fixed adhesive tape, 2. Reverse the separator peeling plate and partially peel off the separator, then attach the positioning tool in which the liquid crystal display element is set. Said polarizing plate? After positioning and partially fixing the exposed end of the adhesive layer of the polarizing plate at a predetermined position on the outer surface of the substrate of the liquid crystal display element, the separator peeling plate is aligned in the direction in which the separator is subsequently peeled off. A process is adopted in which the polarizing plates are continuously attached and laminated while moving the polarizing plate in two directions.

[Effect]

Separator release plate C is used to remove the separator when temporarily fixing the polarizing plate.
: The -(qS) end of the separator is pasted on the fixed adhesive tape and the separator peeling plate is inverted, so the peeling range is small and linear peeling can be performed. In connection with performing temporary fixing by positioning the separator on the positioning tool set, the polarizing plate no longer comes into contact with the base surface at two or more places as in the past.Therefore, after completing the temporary fixing, the separator can be By moving the separator peeling plate relative to the direction of the entrance C: substrate while advancing the liquid crystal display element at a constant angle, the polarizing plate can be bonded without creating air bubbles. I can do it.

Furthermore, since the polarizing plate is positioned and temporarily fixed to the liquid crystal display element as described above, the accuracy of bonding the polarizing plate is improved.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to FIGS. 1 to 8.

FIG. 2 is a sectional view of a liquid crystal display element to which the present invention is applied, and in the figure, 1 and 2 are glass substrates. The glass substrates 1 and 2 are
They are sealed with a sealant B at a predetermined interval.
A liquid crystal is sealed in the sealed space between the substrates 1 and 2. The inner surfaces of each substrate 1 and 2 (detailed illustration of the second board is omitted, but
The transparent electrode and the alignment polarizing plate 4 are arranged on both sides of the C1 polarizer 6, over code layers 7, 8, and an adhesive layer 9, as shown in FIG. 3C.
, 107al- is formed, and the separator 11 is removable (attached to the surface of the adhesive layer 1-9), and the adhesive layer 1o
A reflecting plate 12 is adhered to the surface of. Further, as shown in FIG. 4, the polarizing plate 5 has an overcoat layer 14' formed on one side of the polarizer 15, and a C-niobium barcode layer 15' formed on the other side of the polarizer 16. An adhesive layer 16 is formed, a surface protective film 17 is adhered to the surface g2 of the overcoat layer 14, and a separator 18 is removably adhered to the surface of the adhesive layer 16.

FIGS. 1(α) to (d) are process diagrams of polarizing plate lamination according to the method of the present invention, and the separator release plate 21 used in this process. Details of the positioning tool 22 are shown in Figures 5 and 6 ($
Figure 5 is a front view, Figure 6 is a plan view) and Figure 7 (perspective view).
As shown.

When laminating the polarizing plate 4 (or polarizing plate 5),
First, as shown in FIG. 1 (α), the separator peeling plate 21
One end of the adhesive tape 23 is fixed to the polarizing plate set portion 24 + formed in a concave shape on the separator peeling plate 21.
- Position the polarizing plate 4 with the separator 11 set above it, and attach the adhesive tape 23 to the end of the separator 11. In this case, the adhesion length x1 of the adhesive tape 26 does not need to be very large.

Next, as shown by the two arrows in FIG. 1(α)g, the polarizing plate 4 is inverted about 180° to partially peel off the separator 11.

FIG. 1A) shows the state in which this reversal is completed.

Next, the liquid crystal display element setting part 26 (a two-liquid height display element) formed in a concave shape on the base 25 of the positioning tool 22 is set and positioned, and then placed on the base 25 of the positioning tool 22 as shown in FIG. (The separator peeling plate 21 is placed as shown in C1. Then, the hinge 27 is placed on the base 25 of the positioning tool 22.
After closing the auxiliary tool 28 connected through the auxiliary tool 28 as shown in FIG. The adhesive layer of the polarizing plate 4 is temporarily attached to the outer surface C of the substrate of the liquid crystal display element. This temporary fixing may be done by hand, or may be done by providing the positioning tool 22 with a pressing member that can move up and down and pushing down the pressing member.

In the latter case, rubber is placed on the lower surface of the pressing member and the tip of the polarizing plate 4 is pressed by the rubber. In this case, the smaller the temporary fixing length and the polarizing plate pressing force, the less likely air bubbles will enter.

Next, as shown in FIG. 1(d), open the auxiliary tool 28 horizontally, move the positioning tool 22 to the right, and
α-cra 104 while keeping a constant angle with respect to the substrate.
, 105 and laminate the polarizing plate.
In this case, the separator peeling plate 21 is
The two separators 11 are moved reciprocally to the left, and the separators 11 are laminated while being peeled off.

The following effects can be obtained by performing step C during lamination using this method.

That is, the bonding accuracy when laminating polarizing plates is determined at the time of temporary attachment, and this tendency is particularly large for larger substrates. Conventionally, this temporary fixing has been carried out visually, and as a result, the temporary fixing line is distorted, and the polarizing plate 4 is laminated with C as shown in FIG. 8 (α), reducing the accuracy of the bonding. In the present invention, in order to solve this problem, as shown in FIG.
2.Auxiliary tool 28ξ2 butt against each other to position and temporarily fix? Since C: is set so that the temporary fixing line C is not misaligned, the bonding accuracy is improved. Furthermore, in order to prevent air bubbles from entering during lamination, it is necessary that the area for temporarily fixing the polarizing plate to the substrate be narrow and linear. However, with the conventional method, it is necessary to widen the separator peeling range (x in Figure 9) during temporary attachment, and in addition, the polarizing plate must be removed on the side opposite to the tip of the polarizing plate (portion A in Figure 10) during temporary attachment. As shown in FIG. 8(b), since the adhesive layer is often temporarily attached in a wave-like manner, the adhesive layer comes into contact with the outer surface of the substrate at two or more locations as shown in FIG. 10, causing air bubbles to be mixed in. In the present invention, in order to solve this problem, peeling is performed using a separator peeling plate, and since the peeling tube 1al'2 can be made smaller, the adhesive layer can be reduced to 2.
The substrate Cf is no longer touched at more than one point, and air bubbles are prevented from being mixed in. This prevention of air bubbles is achieved by continuously attaching the polarizing plates after temporary attachment with the polarizing plates tilted (
(The inclination is necessarily maintained due to the presence of the separator peeling plate), which makes it even more reliable.

It becomes fruit.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to improve the lamination accuracy during polarizing plate lamination (C) and to prevent air bubbles from being mixed in.

[Brief explanation of drawings]

FIGS. 1 to 8 show embodiments of the present invention.
Figures (cL) to (d) are polarizing plate lamination process diagrams, Figure 2 is a sectional view of a liquid crystal display element to which the present invention is applied, Figures 3 and 4 are sectional views of each polarizing plate, and Figure 5 is a sectional view of each polarizing plate. FIG. 6 is a plan view of the separator peeling plate used in carrying out the present invention, FIG. ). (h) is a diagram illustrating the details of defects when laminating polarizing plates. FIG. 9 is an explanatory diagram of the procedure for laminating polarizing plates by a conventional method, and FIG. 10 is an explanatory diagram of temporary fixing failures during this lamination. In the figure, 1 and 2 are substrates, 4 and 5 are polarizing plates, 6 and 15 are polarizers, 9 and 16 are adhesive layers, 11.18 are Nanano (Rake, 2
1 is a separator peeling plate, 22 is a positioning tool, 25 is an adhesive tape, 24 is a polarizing plate setting part, 28 is an auxiliary tool, 29
1 and 2 respectively indicate the polarizing plate positioning portion.

Claims (1)

[Claims] A method for manufacturing a liquid crystal display element comprising a pair of substrates, a liquid crystal sealed between the two substrates, and a pair of polarizing plates laminated on the outer surfaces of the two substrates, wherein a separator of the polarizing plates is An adhesive tape fixed to a separator peeling plate is attached to one end, and then the separator peeling plate is reversed to partially peel off the separator, and then the liquid crystal display element is attached to the alignment tool set. After positioning the polarizing plate and temporarily fixing the partially exposed end of the adhesive layer of the polarizing plate to a predetermined position on the outer surface of the substrate of the liquid crystal display element,
A method for laminating polarizing plates, comprising: laminating the polarizing plates by continuously bonding them together while relatively moving the separator peeling plate in a direction in which the separator is successively peeled off.