JPH03116115A - Production of liquid crystal panel - Google Patents

Abstract

PURPOSE:To simplify stages and to reduce cost by placing two substrates opposite to each other so that spacers fixed on the first substrate are brought into contact with an adhesive layer formed on the second substrate before the adhesive layer is solidified and solidifying the adhesive layer. CONSTITUTION:Spacers 4 are fixed on the electrode surface of a first substrate 1a and an orienting film 3a1 is formed on the electrode surface of the first substrate 1a and oriented. An adhesive layer 3b1 whose thickness is sufficiently smaller than the diameter of the spacers 4 is formed on the electrode surface of a second substrate 1b, the spacers 4 fixed on the first substrate 1b are brought into contact with the adhesive layer 3b1 and this layer 3b1 is solidified. Since the spacers 4 do not move in the resulting panel and the two substrates 1a, 1b are fixed by the spacers 4, the peripheral sealing part can be narrowed. Even in the case of many-sided connection, display quality is not lowered, stages are simple and cost can be reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a liquid crystal panel, and more specifically to a method for manufacturing a liquid crystal panel in which liquid crystal is sealed in the gap between two substrates having electrodes on opposing surfaces. This relates to a manufacturing method.

[Prior Art] Conventionally, as a method (gap control method) for maintaining a certain distance between two substrates in a liquid crystal panel in which liquid crystal is sealed in the gap between two substrates having electrodes on opposing surfaces, (a) A method of using a sealing material mixed with a spacer and maintaining the gap with a spacer in the sealing part. (b) After forming an alignment film on the substrate and solidifying it, a spacer (alumina powder, glass fiber, etc.) is used. (C) Coating spacers with adhesive and spraying them on an alignment film formed on a substrate. When bonding the two substrates together, the two substrates are pressed together while heating to melt the adhesive, and then cooled to fix the two substrates and the spacer with the adhesive (disclosed in Japanese Patent Laid-Open No. 54-92339). .)
, etc. are known.

Furthermore, a common method for fixing two opposing substrates is to form a sealing material on the peripheral edge of the substrates and fix them using this sealing material.

[Problems to be Solved] However, in the method (a) above, the substrate is bent at the center of the panel, making it difficult to maintain a uniform gap over the entire panel. Furthermore, in the method (b) above, after the panel is constructed, the spacer moves within the panel, damaging the alignment film and disturbing the alignment of the liquid crystal. In addition, method (c) above has the problem that it is necessary to apply a load while heating the entire surface of the panel when crimping the panel, which complicates the manufacturing process and increases the cost of the spacer coated with adhesive. Ta.

In the conventional substrate fixing method, the sealing material forming portion at the peripheral edge of the substrate becomes a display impossible area, which deteriorates the display quality when a large screen panel is formed by connecting panels.

Therefore, the purpose of the present invention is to maintain a uniform gap over the entire surface of the panel, prevent the spacer from moving within the panel, and prevent deterioration of display quality even when connected on multiple sides, and further simplify the process and reduce costs. The purpose of the present invention is to provide a method for manufacturing a liquid crystal panel that allows for the following.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method for manufacturing a liquid crystal panel in which a liquid crystal is sealed in a gap between two substrates having electrodes on opposing surfaces. a step of fixing and forming a spacer on the electrode surface of the first substrate; a step of forming an alignment film on the electrode surface of the first substrate; a step of performing an alignment treatment on the alignment film;
forming an adhesive layer that is sufficiently thin compared to the particle size of the spacer on the electrode surface of the first substrate; and bringing the spacer fixed to the first substrate into contact with the adhesive layer of the second substrate; and a step of solidifying the.

[Function] Since the spacer is fixedly formed on the alignment film of the first substrate and also fixed on the adhesive layer of the second substrate, the spacer does not move within the panel, and the two substrates are fixed by the spacer. . Therefore, the width of the outer peripheral sealing portion can be made extremely narrow.

[Example] The present invention is a method of manufacturing a liquid crystal panel in which electrodes are formed on the opposing surfaces of two substrates facing each other at a predetermined interval, and liquid crystal is sealed in the gap. Therefore, one embodiment of the manufacturing method according to the present invention will be described with reference to FIGS. 2 to 4.

The substrates 1a and lb are made of glass or the like, and as shown in FIG. 2(a), an electrode 2a made of ITO or the like is formed on the first substrate la by a method such as vapor deposition.

Next, as shown in FIG. 2(b), an alignment film 3 such as polyimide is coated on the electrode 2a by a well-known spin code method or the like.
A1 is applied to a thickness of, for example, about 500 to 1000 angstroms. In this state, the alignment film 3 a 1 has not yet solidified.

Next, as shown in FIG. 2(c), the alignment film 3a1 before solidification is
Sprinkle an appropriate amount of spacer 4, for example, alumina powder with a particle size of 10 μm, on the top with a particle size sufficiently large compared to the thickness of the alignment film,
are scattered on the electrode 2a.

At this time, a part of the bottom of the spacer 4 is attached to the alignment film 3 a
It becomes buried in 1.

Next, the substrate 1a is heat-treated using an oven or the like, and a second
As shown in Figure (d), the alignment film 3a1 is solidified to form a solidified alignment film 3a. Thereby, the spacer 4 is fixed to the solidified alignment film 3a. Then, an alignment process such as rubbing is performed on the alignment film 3a to which the spacer 4 is fixed.

Further, as shown in FIG. 3(a), an electrode 2b is formed on the opposite surface of the second substrate 1b in the same manner as described above, and thereon,
As shown in FIG. 3(b), an adhesive layer 3b1 is applied by a spin code method or the like.

In this state, the adhesive layer 3 b 1 has not yet solidified.

Next, as shown in FIG. 4(a), the first substrate 1a and the second
The spacer 4 fixed to the first substrate 1a is brought into contact with the adhesive layer 3b1 formed on the second substrate 1b and not yet solidified. At this time, the spacer 4 is partially buried in the adhesive layer 3b1.

Next, the adhesive layer 3b1 is baked by heat treatment using an oven or the like while the substrates 1a and 1b are facing each other, and a solidified state 3b is obtained as shown in FIG. 4(b). Thereby, the spacer 4 is fixed to the alignment film 3a and the adhesive layer 3b, and the two substrates 1a and lb are fixed with a predetermined gap.

Finally, as shown in FIG. 4(c), the liquid crystal injection lower is left on the peripheral edge of the panel 10 with the two substrates 1a and lb fixed, and sealed with a sealant 6 such as epoxy resin. The liquid crystal 5 is injected through the liquid crystal injection lower by a well-known method such as vacuum injection, and the liquid crystal injection lower is sealed to complete the liquid crystal panel. FIG. 1 shows this liquid crystal panel.

As the adhesive layer 3b formed on the electrode 2b of the second substrate 1b, a photocurable adhesive may be used in addition to polyimide, polyvinyl alcohol, etc. which are usually used as an alignment film.

Next, another embodiment of the present invention will be described with reference to FIG.

First, as shown in FIG. 5(a), an electrode 2a was formed on a first substrate 1a in the same manner as described above, an alignment film was applied thereon, spacers 4 were dotted thereon, and then heat treated and solidified. A spacer 4 is fixed as an alignment film 3a.

Next, as shown in FIG. 5(b), a sealing material 81 made of a photocurable adhesive is printed on the peripheral edge of the alignment film 3a. At this time, the sealing material 8□ leaves the liquid crystal injection port 11 open, as shown in FIG. 5(c).

Further, an electrode 2b is formed on the second substrate 1b, and an adhesive layer 30b1 made of a photocurable adhesive is formed thereon, as shown in FIG.
As in d), the first substrate 1a is made to face the second substrate 1b, and the spacer 4 is brought into contact with the adhesive layer 30b1. A portion of the spacer 4 is buried in the adhesive layer 30b1.

Thereafter, as shown by the arrow in FIG. 5(e), this is exposed to light to form states 8 and 30b in which the sealing material 8 and adhesive layer 30b1 are simultaneously solidified. (Illustrated in FIG. 5(f).) Thereby, the spacer 4 is also fixed to the adhesive layer 30b, and the two substrates 1a and lb are connected by the spacer 4 and the sealing material 8.

Inject the liquid crystal 5 from the liquid crystal injection port 11, and
By sealing 1, a liquid crystal panel is completed. In this way, when a photocurable adhesive is used for the adhesive layer 30b of the second substrate 1b and the sealing material 8, these can be simultaneously solidified by exposure, and the process of fixing the spacer to the adhesive layer and the process of fixing the substrate The step of sealing the peripheral portion with a sealing material can be performed in a - step. Additionally, photocurable adhesives harden in a short time and do not require complicated thermal management unlike thermosetting adhesives. Since the two substrates are connected by the sealing material and the spacer, they are fixed more firmly. Therefore, it becomes possible to narrow the width of the sealing material, and when a large screen panel is obtained by connecting a plurality of liquid crystal panels in series, the portions that cannot be displayed are reduced, and a high-quality display screen can be obtained.

In the second embodiment, the sealing material is printed as a seal on the first substrate side, but it can also be formed on the second substrate side.

Further, in the above embodiment 1.2, spacers are dispersed to control the gap, but spacers may be formed on the alignment film by patterning.

Further, in any of the embodiments, the liquid crystal injected into the panel is not particularly limited.

[Effect] The two substrates are placed opposite each other in such a manner that the spacer fixed to the first substrate is brought into contact with the adhesive layer formed on the second substrate before solidification, and then the adhesive layer is solidified. Since the spacer is fixed to both substrates, it does not move within the panel, and the gap between the substrates can be maintained uniformly over the entire surface of the panel, making the process simple and effective in reducing costs.

Furthermore, since the width of the upper part of the outer peripheral village can be made extremely thin, when connecting panels on multiple sides, the area that cannot be displayed becomes smaller and the display quality is improved.

Furthermore, by making the adhesive layer formed on the second substrate a photo-curing type, it is possible to solidify the adhesive layer in a short time, and the adverse effects of heat can be eliminated. Furthermore, by using an adhesive layer and sealing material made of a light-curing adhesive, it is possible to solidify the sealing material at the same time as the adhesive layer is solidified, reducing the number of steps and simplifying the work. .

[Brief explanation of drawings]

FIG. 1 is a sectional view of a liquid crystal panel based on the manufacturing method of the present invention, FIGS. 2(a) to (d) are sectional views of one of the substrates explaining the manufacturing process, and FIGS. ) is a sectional view of the other board, Figures 4(a) to (C) are assembly diagrams, and Figure 5(a)
-(f) are explanatory diagrams of each process of another example. 1a... First substrate, 1b... Second substrate, 2a, 2b... Electrode, 3a... Alignment film before solidification, 3a... Alignment film after solidification, 3b... Adhesive layer before solidification. , 3b...Adhesive layer after solidification, 4...Spacer 5...Liquid crystal, 8...Photocurable encapsulant before solidification, 8...Photocurable encapsulant after solidification , 30b...Photocurable adhesive layer before solidification, 30b...Photocurable adhesive layer after solidification. Below

Claims (3)

[Claims] (1) A method for manufacturing a liquid crystal panel in which liquid crystal is sealed in a gap between two substrates having electrodes on opposing surfaces, including the step of fixing and forming a spacer on the electrode surface of a first substrate; forming an alignment film on the electrode surface; performing an alignment treatment on the alignment film; forming an adhesive layer sufficiently thinner than the spacer particle size on the electrode surface of the second substrate; the spacer fixed to the second
A method for manufacturing a liquid crystal panel, comprising the step of solidifying the adhesive layer by bringing it into contact with the adhesive layer of the substrate. (2) The method for manufacturing a liquid crystal panel according to claim 1, wherein the adhesive layer is a photocurable adhesive. (3) Forming a sealing material made of a photocurable adhesive on the peripheral edge of the opposing surface of the first substrate or the second substrate, and simultaneously solidifying the adhesive layer made of the photocurable adhesive. 3. The method of manufacturing a liquid crystal panel according to claim 2, further comprising solidifying the sealing material.