MXPA97005090A - Composition of heat resistant polymer, capped formed alignment using the same ypanel liquid crystal visualization that keeps the alineamine layer - Google Patents

Abstract

The present invention relates to a heat-resistant polymer composition, characterized in that it comprises 10 to 25% by weight of a polyimide or polyamide resin, 0.1 to 1% by weight of an adhesive agent and the remainder of a solvent. An alignment layer, characterized in that it comprises a polyimide or polyamic acid resin and an adhesive agent in a weight ratio of 99.5: 0 to 94

Description

COMPOSITION OF HEAT RESISTANT POLYMER, FORMED ALIGNMENT LAYER USING THE SAME AND LIQUID CRYSTAL DISPLAY PANEL WHICH HAS THE ALIGNMENT LAYER BACKGROUND Pg IMYSHCIQM The present invention relates to a liquid crystal display or display panel (LCO) and more particularly to a thermo-resistant polymer composition and alignment layer formed using the thermo-resistant polymer composition and an LCD having the alignment layer. In general, a liquid crystal molecule has the intermediate property of a liquid and that of a solid, which has the fluidity of a liquid and has the optical property of a solid, and can be changed in its optical anisotropy by an electric field or heat . A liquid crystal display (LCD) uses these properties and is typically used as a flat panel display. Figure 1 is a schematic sectional view of a general LCD, in which transparent electrodes 3 and 3 'composed of indium tin oxide (ITO) are respectively formed in upper and lower substrates 2 and 2' made of glass. insulating layers 4 and 4 'and alignment layers 5 and 5' for aligning liquid crystals are formed sequentially in the transparent electrodes 3 and 3 '. Spacers 6 are arranged between the alignment layers 5 and 5 'with a cell space. A liquid crystal material is REP: 25075 injected into the cell space to form a liquid crystal layer 7. Polymerisation plates 1 and 1 'for polarizing incident light and transmission are provided on the outside of substrates 2 and 2'. Figure 2 shows a directional relationship between the liquid crystal molecules and an alignment surface (substrate), wherein a pre-tilt angle refers to the angle formed by the substrate surface and a liquid crystal director. An alignment layer should be formed by using an appropriate alignment material or using an appropriate alignment method so that the pre-tilt angle of the liquid crystal can be adjusted within a suitable range, which is essential to improve display performance of the LCD. For the purpose of forming an alignment layer, a rubbing treatment has been employed in general, that is, a polymeric resin film such as a poly film is formed on a substrate where an electrode is formed and then the film rub with a piece of cloth. ° 5 «s | U | uSd0 with the rub treatment, a layer composition of > a < The invention includes a polyarylene resin coated onto substrates wherein an electrode layer is formed and then thermally treated at 200 to 250 * C for about 1 hour and subjected to rubbing treatment to form an alignment layer. Then, to form a liquid crystal layer, a spacer is coated on the substrate, wherein the alignment layer is formed and the upper and lower substrates are sealed with a predetermined cell space. Subsequently, a liquid crystal composition is injected into the cell space and then thermally treated again at about 100 ° C. However, the alignment layer can be damaged by the heat treatment and then change the pre-tilt angle or degree of alignment undesirably, resulting in deterioration of LCD display performance. SUMMARY OF THE INVENTION In order to solve the above problem or problems, it is an object of the present invention to provide a thermo-resistant polymer composition having excellent thermal stability. Another object of the present invention is to provide an alignment layer formed of the heat-resistant polymer composition and which can exert stable alignment characteristics. Yet another additional object of the present invention is to provide a liquid crystal display (LCD) with improved display performance by an alignment layer having excellent alignment characteristics.

Accordingly, to achieve the first objective, a thermo-resistant polymer composition is provided of which 10-25% by weight is a polyamide resin or polyamic acid, 0.1 to 1% by weight is an adhesive agent and the rest is a solvent. Particularly, it is preferable that the adhesive agent and the polyimide or polyamide resin are mixed in a weight ratio of 0.5: 99.5 to 6:94 on a solid weight basis. The adhesive agent is not specifically restricted as long as a resin having adhesiveness, and an epoxy resin is preferably used. At this time, the weight average molecular weight of the epoxy resin is preferably 5,000 to 30,000. The solvent used in the polymer composition according to the present invention is not specifically restricted and preferably chloroform or N-methyl-pyrrolidone (NMP) is used. The second objective of the present invention is achieved by an alignment layer that includes the adhesive agent and polyimide or polyamic acid in a weight ratio of 0.5: 99.5 to 6:94.

The third objective of the present invention is achieved by an LCD having the alignment layer including the adhesive agent and polyimide or polyamic acid in a weight ratio of 0.5: 99.5 to 6:94. In accordance with the present invention, the adhesive agent is added to the conventional composition to form an alignment layer in an appropriate ratio, thereby improving the adhesiveness of the alignment layer with respect to the substrate. Also, while the epoxy resin and polymer both align in the same direction during the rubbing treatment, the polymer chain can be fixed and the initial state of friction-treated alignment can be retained even after heat treatment or liquid crystal injection. BRIEF DESCRIPTION OF THE DRAWINGS The above objects and advantages of the present invention will be more apparent when describing in detail a preferred embodiment thereof with reference to the accompanying drawings in which: Figure 1 is a sectional view of a general liquid crystal exhidor; and Figure 2 is a diagram showing the directional relationship between liquid crystal molecules and an alignment surface (substrate).

ESCRTPCIOW OF THE PREFERRED MODALITIES In the present invention, there is provided a thermosetting polymer composition further comprising an adhesive agent, as compared to a conventional composition made of polyimide, an alignment layer formed using the same and an LCD which has an alignment layer. As the adhesive agent, an adhesive epoxy resin having a weight average molecular weight of 5,000 to 30,000 preferably is employed. At this time, it is preferable that the alignment layer includes an adhesive agent and an epoxy resin in a weight ratio of 0.5: 99.5 to 6:94 on a solid weight basis. If the amount of adhesive agent with respect to the polyimide resin exceeds 6% by weight, the adhesiveness becomes too high to ensure a uniform rubbing treatment. If the amount of adhesive agent with respect to the polyimide resin is less than 0.5% by weight, the adhesive agent does not exhibit a desired effect. Next, the present invention will be described in more detail through detailed embodiments. However, the following embodiments are only examples of the invention and the scope of the invention is not limited thereto. In the following examples and comparative examples, NMP is employed as the solvent Z10 manufactured by Aldrich Industries, Co., Ltd., is employed as the epoxy resin and RN 715 manufactured by Nissan Chemical Industries, Ltd., is employed as the polyimide resin . These resins were used in the form of a solution (10%) respectively. EXAMPLE 1 0.5 g of an epoxy resin solution and 99.5 g of a polyimide resin solution were mixed to form a polymer composition. The composition was uniformly coated on a glass substrate where an electrode ITO whose surface was cleaned was formed and heat-treated at approximately 220 ° C for about 1 hour to evaporate and dry the solvent, thereby forming a layer of polyimide resin, and rubbing it to form an alignment layer. a spacer was coated using a conventional method, and top and bottom substrates were sealed, then liquid crystals were injected into the cell space formed between the upper and lower substrates and heat-treated at approximately 100 ° C for approximately 25 minutes. of completing the LCD, the change in pre-tilt angles is observed by a crystal rotation method and the alignment properties of the liquid crystals of the liquid crystal layer were observed under a polarizing microscope EXAMPLE 2 Except for 3 g of an epoxy resin solution and 97 g of a polyimide resin solution used, an LCD is manufactured in the same way as described in n Example 1. Then, the change in the pre-tilt angles and alignment properties of the liquid crystals were observed. EXAMPLE 3 Except that 6 g of an epoxy resin solution and 94 g of a polyimide resin solution were used, an LCD is manufactured in the same manner as described in Example 1. Then, the change in the angles of Tilt and alignment properties of liquid crystals was observed. COMPARATIVE EXAMPLE 1 Except that an epoxy resin solution is not used, an LCD is manufactured in the same manner as described in Example 1. Then, the change in pre-tilt angles and alignment properties of the crystals was observed. liquids. COMPARATIVE EXAMPLE 2 Except that 0.2 g of epoxy resin solution and 99.8 g of a polyimide resin solution are used, an LCD is manufactured in the same manner as described in Example 1.

Then, the change in the pre-tilt angles and alignment properties of the liquid crystals is observed.

COMPARATIVE EXAMPLE 3 Except for 8 g of epoxy resin solution and 92 g of polyimide resin solution used, an LCD is manufactured in the same manner as described in Example 1. Then, the change in the angles of tilt and alignment properties of liquid crystals. As a result, in Examples 1 to 3, little change in pre-tilt angles was observed and liquid crystals were uniformly aligned, that is, the alignment property was good. On the other hand, in Comparative Example 1, the alignment of the liquid crystals is interrupted, that is, the alignment properties of the liquid crystals were not uniform. Also, pre-tilt angles were not maintained within a desirable range. In Comparative Example 2, the pre-tilt angles and alignment status of the liquid crystals were both lower in the cases of Examples 3. In Comparative Example 3, the epoxy resin was added in excess, which resulted in too much adhesiveness, making material handling difficult in this way. As described above, since an adhesive agent is included in the heat-resistant polymer composition of the present invention, the thermal stability thereof is markedly improved. In this way, the change in the pre-tilt angles of the liquid crystals or the alignment break can be greatly reduced by forming an alignment layer using the thermo-resistant polymer composition and manufacturing an LCD. Therefore, the LCD manufactured in accordance with the present invention has improved display characteristics. It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the production of the objects to which it refers. Having described the invention as above, the content of the following is claimed as property:

Claims (11)

1. CLAIMS 1. A heat-resistant polymer composition, characterized poi, comprises 10 to 25% by weight of a polyimide or polyamic acid resin, 0.1 to 1% by weight of an adhesive agent and the remainder of a solvent. The composition according to claim 1, characterized in that the mixing ratio of the polyimide resin or polyamic acid to the adhesive agent is 99.5: 0.5 to 94: 6 on a solid weight basis. 3. The composition according to any of claims 1 or 2, characterized in that the adhesive agent is an epoxy resin. 4. The composition according to claim 3, characterized by the weight average molecular weight of the epoxy resin is 5,000 to 30,000. The composition according to claim 1, characterized in that the solvent is at least one selected from the group consisting of chloroform and N-methylpyrrolidone. 6. A coating capability, characterized by the fact that it comprises a polyimide resin or polyamic acid and an adhesive agent in a weight ratio of 99.5: 0.5 to 94: 6. 7. An alignment layer according to claim 6, characterized in that the adhesive agent is an epoxy resin. 8. An alignment layer according to claim 7, characterized in that the weight average molecular weight of the epoxy resin is 5,000 to 30,000. 9. Q visual screen / glass pane 1íq? .ridr > (HE), CHARACTERIZATION ± »because it comprises an alignment layer having a polyimide or polyamic acid resin and an adhesive agent in a weight ratio of 99.5: 0.5 to 94: 6. 10. The LCD according to claim 9, characterized in that the adhesive agent is an epoxy resin. The LCD according to claim 9, characterized in that the weight average molecular weight of the epoxy resin is 5,000 to 30,000.