JP2000206520A - Liquid crystal display panel and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to provide a liquid crystal display panel of a small size having a high effective display surface rate with good reliability and yield. SOLUTION: An adhesive 3 is disposed between a roughened surface 5a2 of a picture frame part 5a1 formed on the peripheral with a black matrix 5a of color filters 5 disposed on the inside surface of one glass substrate 1 and another glass substrate 2, by which a pair of the glass substrates 1 and 2 are adhered. The strength of adhesion to the adhesive 3 is improved by the surface roughening described above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal display panel and a method for manufacturing the same, and more particularly, to a liquid crystal color display panel and a method for manufacturing the same.

[0002]

2. Description of the Related Art As shown in FIG. 3, a liquid crystal display panel is formed by bonding a pair of glass substrates a and b with an adhesive c disposed in a frame shape between peripheral portions thereof and sealing them. Liquid crystal d is enclosed between them. The pair of glass substrates a and b is bonded between the glass substrates a and b, and has a color filter e and a color filter e provided inside one glass substrate a as shown in FIG. May be performed between the glass substrate b and the other glass substrate b.

In recent years, liquid crystal display panels have been further miniaturized,
In order to improve the effective display area ratio, a so-called narrow frame design for minimizing a frame-shaped dead space formed in the periphery has been made. For this purpose, it is effective to reduce the width of the adhesive to reduce the width of the seal with the adhesive c. However, the reduction in the thickness of the adhesive c reduces the adhesive strength, and a plurality of sheets are manufactured using a common glass substrate. After that, when the individual liquid crystal display panels are cut, the seal is peeled off by mechanical stress such as external force or vibration, which leads to a fatal defect such that the yield is reduced in manufacturing.

Therefore, as shown in FIG. 3, a structure in which an adhesive c is arranged and bonded between the periphery of the color filter e of one glass substrate a and the other glass substrate b is selected. The frame part which is a dead space on the liquid crystal display formed around the black matrix is effectively used.

[0005]

However, in experiments at the manufacturing stage of the present inventors, the adhesion by the adhesive c was caused by the mechanical stress and thermal deterioration of the seal in a reliability test. Or, the interface is more easily separated at the interface between the color filter e and the black matrix than at the interface with the conductive film provided on the surface.

Therefore, even if the liquid crystal display panel having the bonding structure shown in FIG. 3 is to be manufactured and provided with a good yield at a high yield, the adhesive c must be thickened, contrary to thinning. Absent. For this reason, miniaturization and improvement of the effective display area ratio are not yet sufficient.

An object of the present invention is to provide a liquid crystal display panel capable of providing a small-sized liquid crystal display panel having a high effective display area ratio with high reliability and yield, and a method of manufacturing the same.

[0008]

In order to achieve the above-mentioned object, a liquid crystal display panel according to the present invention comprises a pair of glass substrates which are sealed by being adhered to each other with an adhesive having a peripheral portion arranged in a frame shape. In the case where the liquid crystal is sealed between the glass substrate and the other glass substrate, the black matrix of the color filter provided on the inner surface of one of the glass substrates forms a peripheral surface and the roughened surface of the frame portion. The main feature is that a pair of glass substrates is bonded by disposing an adhesive.

Further, according to the method of manufacturing a liquid crystal display panel of the present invention, the surface of a black matrix of a color filter on a glass substrate having a color filter formed on one surface is roughened.
This glass substrate faces the other glass substrate on which the color filter is not formed on the color filter side, and the frame portion formed around the black matrix and the other glass substrate are bonded with an adhesive and sealed. The main feature is that liquid crystal is sealed between glass substrates to manufacture a liquid crystal display panel.

In the liquid crystal display panel constructed or manufactured as described above, one glass substrate having a color filter and the other glass substrate having no color filter have a black matrix of a color filter formed in a peripheral portion. The black matrix is adhered by an adhesive at the frame part, but the surface of the frame part of the black matrix is roughened, and the adhesive strength with the adhesive according to the degree of the surface roughening is determined by the adhesive. Since it increases so as to be approximately equal to or greater than the adhesive strength between the other glass substrate or the conductive film on the other glass substrate, the adhesive is limited to a limit determined by the adhesive strength between the adhesive and the other glass substrate. It is possible to secure a sufficient adhesive strength by thinning the wire, and to further reduce the size and improve the effective display area ratio with sufficient reliability and yield.

Although the surface can be roughened in any manner, it is preferable to carry out the treatment with a solution because the work is easy. If the solution is acid or alkali, the surface can be roughened by a relatively low temperature and short time treatment.

If the surface roughening is performed only on the surface of the frame portion of the black matrix, the processing range becomes a necessary minimum area, so that there is no waste in processing operation, time and cost, which is preferable.

Further objects and features of the present invention will become apparent from the following detailed description and drawings. Each feature of the present invention can be used alone or in various combinations in combination.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a liquid crystal display panel and a method of manufacturing the same according to an embodiment of the present invention will be described in detail with reference to FIGS.

In the liquid crystal display panel of the present embodiment shown in FIG. 1, a pair of glass substrates 1 and 2 are sealed by bonding the peripheral portions thereof with an adhesive 3 arranged in a frame shape as shown in FIG. This is a liquid crystal display panel having a general structure in which a liquid crystal 4 is sealed between substrates 1 and 2 and a color filter 5 is provided on the inner surface of one glass substrate 1.

In the present embodiment, in particular, the color filter 5
The adhesive 3 is disposed between the roughened surface 5a2 of the frame portion 5a1 formed around the black matrix 5a and the other glass substrate 2, so that the pair of glass substrates 1, 2
Is glued.

Other than this adhesive structure, there is no particular difference from the structure of a general liquid crystal color display panel. On the opposing surfaces of the glass substrates 1 and 2, a so-called conductive film (not shown), which is a transparent electrode, is provided. Is provided. An alignment film 6 is formed and wrapped on the innermost surface of the sealed area of the liquid crystal 4. Spacers 7 are provided between the alignment films 6 of the glass substrates 1 and 2, and the glass substrates 1 and
The necessary gap is secured between the two.

The manufacturing method according to the present embodiment for manufacturing the liquid crystal color display panel shown in FIGS. 1 and 2 is particularly different from the general method for manufacturing the liquid crystal color display panel except for performing the above-described roughening treatment. There is no place. Therefore, a description of well-known steps will be omitted. In the glass substrate 1 having the color filter 5 formed on one surface, the surface of the black matrix 5a of the color filter 5 is roughened. Then, the glass substrate 1 faces the other glass substrate 2 on which the color filter 5 is not formed on the color filter 5 side, and the frame portion 5a1 formed around the black matrix 5a and the other glass substrate 2 are connected. The gap is adhered and sealed with an adhesive 3, the liquid crystal 4 is sealed between the glass substrates 1 and 2, and the liquid crystal display panel 11 is manufactured. If the surface roughening is performed only on the surface 5a2 of the frame portion 5a1 of the black matrix 5a, the processing range becomes a necessary minimum area, so that there is no waste in the processing operation, time, and cost, which is preferable. However, in principle, it is not limited to this.

The adhesive 3 is made of, for example, an epoxy resin as a main material. Usually, the adhesive 3 has a strength smaller than that of the glass substrate 1, 2 or a conductive film made of tin oxide or indium oxide. The adhesive strength to the black matrix 5a made of chromium oxide or a resin substituted for the same is smaller. Therefore, if the glass substrates 1 and 2 are simply bonded to each other between them, depending on the thickness of the adhesive 3, a plurality of glass substrates may be manufactured using a common glass substrate after manufacturing a liquid crystal color display panel. Interfacial separation between the adhesive 3 and the black matrix 5a due to mechanical stress such as external force and vibration when the individual liquid crystal color display panels 11 are cut, and thermal deterioration of the seal in a reliability test. It's easy to do.

However, in the liquid crystal color display panel 11 constructed and manufactured as described above, one of the glass substrates 1 having the color filters 5 and the other glass substrate 2 having no color filters are formed by the color filters. A frame portion 5 formed by a black matrix 5a at the periphery
a1 is adhered by the adhesive 3, but the surface 5a2 of the frame portion 5a1 of the black matrix 5a is roughened, and the adhesive strength with the adhesive 3 increases in accordance with the degree of the roughening, The strength can be set so as to be approximately equal to or higher than the adhesive strength between the adhesive 3 and the other glass substrate 2 or the conductive film thereon. Thereby, the adhesive 3 can be thinned to a limit determined by the adhesive strength between the adhesive 3 and the other glass substrate 2, and a sufficient adhesive strength between the glass substrates 1 and 2 can be secured. Therefore, it is possible to further reduce the size and improve the effective display area ratio with sufficient reliability and yield.

Roughening can be performed, for example, mechanically or electrically.
It can be done both chemically and electrically. The surface may be roughened in any manner, but it is preferable to perform the treatment with a solution because the work is easy. If the solution is acid or alkali, the surface can be roughened by a relatively low temperature and short time treatment.

In this embodiment, a 0.7 mm thick common electrode glass substrate 1 on which a black matrix 5a is formed is immersed in a hydrochloric acid solution having a pH of 2.5 and a temperature of 40 ° C. for 7 minutes to form a surface of the black matrix 5a. This glass substrate 1 was bonded to another glass substrate 2 at the portion of the roughened surface 5a2 of the frame portion 5a1 of the black matrix 5a with the adhesive 3 arranged in a frame shape with a line width of 1 mm. . With respect to the obtained liquid crystal color display panel 11, glass substrates 1, 2 were used for a total of eight locations A to H shown in FIG.
A peeling test was carried out using a tensile strength tester, and the results were compared with those of a conventional example which was adhered under the same conditions except for the above-mentioned roughening treatment. The results are as shown in Table 1.

[0023]

[Table 1]

As is clear from Table 1, the tensile force required for the bonded portion to peel at each point, that is, the seal adhesion strength by the adhesive, is about twice as large as that of the conventional example. As a result, interface peeling due to the mechanical stress and the deterioration of the adhesive in the reliability test was sufficiently prevented, and the reliability and yield were improved. In some cases, the adhesive 3 can be made thinner than in the above embodiment to further reduce the size and improve the effective display area ratio.

When only the surface 5a2 of the frame portion 5a1 on the surface of the black matrix 5a is roughened by chemical etching using a solution, the solution may be brought into contact with the solution by, for example, applying the solution only to a necessary portion. However, as a specific method, the other portion may be masked with a photoresist or the like, the glass substrate 1 may be immersed in a hydrochloric acid solution, and the photoresist may be removed after roughening.

In addition, in addition to the above, the effect was recognized even when the concentration of the hydrochloric acid solution was adjusted to pH 3.0.
There was an effect even at 5 to 1.0. The highest effect was observed at a liquid temperature of 40 ° C, but the effect was also effective at a temperature of 30 to 50 ° C. The immersion time is most preferably 7 minutes, but the effect was obtained even when the immersion time was 5 to 10 minutes. Further, as for the acid in the solution, other acids such as nitric acid and sulfuric acid were effective in addition to hydrochloric acid. In addition, the effect of surface roughening was recognized even with an alkali such as sodium hydroxide.

Therefore, any of these cases belong to the scope of the present invention.

[0028]

According to the present invention, the glass substrates are adhered to each other by the adhesive at the frame portion formed around the peripheral portion of the black matrix of the color filter of one glass substrate. Surface is roughened, and the adhesive strength with the adhesive is increased so as to be approximately equal to or greater than the adhesive strength between the adhesive and the other glass substrate or the conductive film thereon. The adhesive can be thinned to the limit determined by the adhesive strength between the glass substrate and the other glass substrate, and sufficient adhesive strength can be secured.Therefore, based on sufficient reliability and yield, further miniaturization and effective display area ratio can be achieved. Improvement can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view conceptually showing a liquid crystal color display panel and a method of manufacturing the same according to an embodiment of the present invention.

FIG. 2 is a plan view of the liquid crystal color display panel of FIG. 1 and shows locations where seal peel strength is measured.

FIG. 3 is a sectional view conceptually showing a conventional liquid crystal color display panel and a method of manufacturing the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 2 Glass substrate 3 Adhesive 4 Liquid crystal 5 Color filter 5a Black matrix 5a1 Frame 5a2 Surface 11 Liquid crystal color display panel

Claims (5)

[Claims] 1. A liquid crystal display panel in which a pair of glass substrates is sealed by bonding with a frame-shaped adhesive between the peripheral portions and seals liquid crystal between the glass substrates, and is provided on an inner surface of one of the glass substrates. An adhesive is disposed between the roughened surface of the frame portion formed by the black matrix of the color filter and the other glass substrate, and the pair of glass substrates is bonded. LCD panel. 2. A surface of a black matrix of a color filter of a glass substrate on which a color filter is formed on one surface is roughened, and the glass substrate is opposed to another glass substrate on which a color filter is not formed on the color filter side,
A liquid crystal display characterized in that a liquid crystal display panel is manufactured by bonding and sealing a frame portion formed around the black matrix and the other glass substrate with an adhesive and sealing the liquid crystal between the glass substrates. Panel manufacturing method. 3. The method for manufacturing a liquid crystal display panel according to claim 2, wherein the roughening is performed by treating with a solution. 4. The method according to claim 3, wherein the solution is an acid-based or alkali-based solution. 5. The method for manufacturing a liquid crystal display panel according to claim 2, wherein the roughening is performed only on the surface of the frame portion of the black matrix.