JPH0472210B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method of manufacturing a functional element constructed by providing a certain gap between at least two or more substrates, and relates to a method of forming the gap. In this invention, we will specifically explain the display element in detail, but it goes without saying that any device can be applied to the purpose of keeping the gap between two or more substrates constant.Display elements include liquid crystal displays, electrochromic ( ECD), electrophoretic device (EPID), etc., but all of them have a structure in which a certain gap is provided between two or more substrates. FIG. 1 is a cross-sectional view of a twisted nematic type liquid crystal panel, which is a typical liquid crystal display, showing an upper transparent substrate 1, a lower transparent substrate 2, an upper transparent electrode 3, a lower transparent electrode 4, a liquid crystal layer 5, It is composed of a polarizing plate 6, a lower polarizing plate 7, a reflecting plate 8, a sealing material 9, a seal spacer 10, and a spacer material 11. The upper and lower transparent substrates 1 and 2 are made of inorganic glass or plastic.
The seal part spacer material 10 in the seal material 9 is 5~
A spacer material such as glass fiber or alumina of about 12 μm is inserted to maintain a certain gap between the substrates, but as LCD panels become larger and thinner, the gap between the upper and lower substrates 1 and 2 has been reduced. It is becoming difficult to keep it constant. As a result, problems arise such as coloring of the panel due to light interference and decreased production yield due to uneven response. In order to eliminate the above drawbacks, the spacer material 11 is
The materials used include glass fiber, metal oxides such as alumina oxide, polystyrene, polyester, polyethylene, polyimide,
It is a high-molecular organic compound such as Teflon, epoxy, or acrylic, and is cylindrical or spherical in shape. The conventional method for shaping the spacer material 11 has been a dry method in which the spacer material is placed on a sieve and spread over a substrate shape using vibration or compressed air. The first drawback of this method is that most of the spacer materials are insulators and are easily charged, so the spacers may bond or overlap during sieving or on the top surface of the sprinkled substrate. This resulted in uneven gaps between substrates and poor appearance, resulting in poor product yields. The second drawback is that it is difficult to control the amount of spacer material sprinkled, and the amount of spacer material is sprinkled unevenly, resulting in a large consumption amount of spacer material. The third drawback is that it is difficult to supply the spacer material and it needs to be done frequently, so the processing time is very long. As a result of the above, the conventional methods have extremely poor quality and are also extremely expensive. The present invention has been made to eliminate such drawbacks, and an object of the present invention is to prevent the spacer materials from joining together, and to spread the spacer materials evenly and uniformly in a separated state at a low cost. Therefore, the inventor of the present invention solved the conventional drawbacks by mixing a spacer material with an organic solvent and spraying the mixture with an atomizer. Examples of organic solvents that can be used include solvents with good volatility, fluorochlorinated hydrocarbons such as trifluoromethane, difluorotetrachloroethane, trifluorotrichloroethane, ethylene chloride such as trichloroethylene, trichloroethane, etc. Examples include chloroethanes, acetone and other alcohols, benzene, toluene, xylene, methylene, naphtha, methanol, and ethanol. Among these, fluorochlorinated hydrocarbons are superior because they are safe and do not affect the quality of alignment processing agents, liquid crystals, and other substrate parts. Furthermore, in order to eliminate binding and overlapping prevention due to charging of the spacer agent, 3 to 10%, more preferably 5% (vo 1%) of an alcohol that is a dielectric solvent and has a hydrophilic group is mixed in the solvent. Spray with the solvent. By setting the content in the range of 3 to 10%, the volatility of the alcohol is good, so that the alcohol does not adhere to and remain on the substrate surface. Furthermore, it prevents the spacer material from bonding and allows it to be evenly distributed over the front surface of the substrate. Hereinafter, the details of the present invention will be explained with reference to Examples. Practical example 1 Glass fiber spacer material with a diameter of 10μ and a length of 50μ to 200μ is mixed with trifluorotrichloride ethane + ethyl alcohol 5VO1% solvent, stirred with ultrasonic waves for 15 minutes, and then compressed with air using a spray gun. (Other gas pressures such as nitrogen gas and argon gas may be used) 40 cm from the top of the substrate at 0.5 Kg/cm ²
I sprayed it for several seconds at a distance of . Figure 2 shows how the spray method is applied. 12
1 is a substrate, 13 is a spray gun, and 11 is a glass fiber. The results were good as shown in Table 1. Example 2 Three polystyrene ball spacer materials with a diameter of 8μ
It was mixed with a solvent of trifluorotrichloride ethane + ethyl alcohol 5 vol 1% and then sprayed under the same processing conditions as in Example 1. As shown in Table 1, the results were good. Comparative Example 1 A glass fiber spacer material with a diameter of 10 μm and a length of 50 μm to 200 μm was mixed with 100% solvent of trifluorotrichloroethane (Daiflon S-3 manufactured by Daikin), processed under the same processing conditions as in Example 1, and sprayed. I threw a sprinkle. As a result, compared to Example 1, the bonding rate was higher. Comparative Example 2 The same spacer material as in Example 1 was mixed in a solvent of trifluorotrichloride ethane + ethyl alcohol 5vo1%,
Hereinafter, as a result of spraying under the processing conditions of Example 1, the results shown in Table 1 were obtained. The same spacer material as in Example 1 was mixed in a solvent of trichloroethane + ethyl alcohol 5% vol 1%, and the following was done.
As a result of spraying under the processing conditions of Example 1, the results shown in Table 1 were obtained. Comparative Example 3 The same spacer material as in Example 1 was mixed in a solvent of trichloroethane + ethyl alcohol 5vo1%,
As a result of spraying under the processing conditions of Example 1, the results shown in Table 1 were obtained. Comparative Example 4 A polystyrene ball spacer with a diameter of 8 μm was mixed with a 100% trifluorotrichloroethane solvent and then sprayed under the same processing conditions as in Example 1. As a result, the results shown in Table 1 were obtained. Comparative Example 5 Similar to Example 2, a spacer material was mixed with trifluorotrichloride ethane + ethyl alcohol 5% vo 1% solvent,
After stirring with ultrasonic waves for 15 minutes, the mixture was sprayed several times with a pump-type hand sprayer at a distance of 40 cm from the top of the substrate, and the results shown in Table 1 were obtained. Table 1 summarizes the test results for each of the above examples, comparative examples, and conventional dry method.

[Table] Here, the binding rate g is defined by the following formula. g=M/(M+S) Here, M is the number of groups of 4 or more spacer materials, and S is the total number of groups of less than 4 pieces. As can be seen from Table 1, the bonding rate is high in the conventional dry method, and it can be seen that the bonding, or clustering, of the spacer materials is very large. In particular, polystyrene balls tend to have a high bonding rate g. As a result of the above examples, the bonding and overlapping ratios could be reduced from 1/2 to 1/100 compared to the conventional dry spreading method using a film. In the following examples, 3 fluoride 3 was also used as the main organic solvent.
Although ethane chloride was used, the results in Table 1 show that trifluorotrichloroethane had a lower binding rate and better results than trichloroethane in Comparative Example 3. In addition, better results were obtained with a mixture containing a small amount of ethyl alcohol than with a mixture containing 100% trifluorotrichloroethane. The reason for this is
This seems to be related to the hydroxyl group of the alcohol, and it is thought that something with a hydrophilic group is better. Incidentally, similar results have been obtained with other alcohols and organic solvents with ketone bonds (eg, acetone). Further, in the examples, the effects of the present invention were explained using typical spacer materials as an example, but similar effects were obtained with other spacer materials. In the above embodiments, a liquid crystal display is taken as an example, and it is clear that the present invention can be similarly applied to a structural/functional element in which a certain gap is provided between a plurality of substrates. As described above, according to the present invention, 3 to 10 vol of alcohol is added to the organic solvent consisting of fluorochlorinated hydrocarbons.
Since the mixed solvent and the spacer material were mixed, it was possible to prevent the spacer material from bonding. Furthermore, since the arrangement was such that the ratio of the number of clusters consisting of four or more spacer materials to the total number of clusters consisting of bonds of spacer materials was 4% or less, there were no clusters due to the bonding of spacer materials. It has the excellent effect of not causing display unevenness or non-uniform gap spacing even when

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional TN type liquid crystal panel. FIG. 2 is a diagram showing an embodiment of the present invention. 1... Upper transparent substrate, 2... Lower transparent substrate, 3...
Upper transparent electrode, 4... Lower transparent electrode, 5... Liquid crystal layer,
6... Upper polarizing plate, 7... Lower polarizing plate, 8... Reflecting plate, 9... Seal material, 10... Spacer material for seal portion, 11... Spacer material, 12... Substrate, 13
...spray gun.

Claims (1)

[Claims] 1 Mix a mixed solvent consisting of an organic solvent made of fluorochlorinated hydrocarbons to which 3 to 10 vol% of alcohol has been added and a spacer material, and create 4 or more spacers for the total number of the group consisting of the combination of the spacer materials. The solvent and the spacer material are dispersed in a spray form by the pressure of compressed air or gas so that the ratio of the number of groups consisting of bonded materials is 4% or less on the substrate to be processed. Method of forming spacer material.