JP5083576B2 - Color filter manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a color filter for a liquid crystal display device and a color filter manufacturing apparatus used therefor.

  In the color filter manufacturing process, a chromium film is formed on a transparent substrate such as glass by using a vacuum film forming method, a photoresist is applied and a photomask is placed, and exposure, development, chromium etching, and photoresist removal are performed. The step of forming a black light-shielding layer comprising a stripe pattern or a lattice pattern, applying a coloring light-sensitive material from above the black light-shielding layer, placing and exposing a photomask, and developing to develop a colored pattern And forming a plurality of colored layers by repeating this colored pattern for R, G and B colors, and forming a transparent electrode layer by depositing indium tin oxide on these colored layers. In this automated line, the substrate is transported to the substrate suction plate in a certain process by the substrate transport arm, the substrate is mounted on the substrate suction plate, the processed substrate is peeled off from the substrate suction plate, and transported to the next process. I have to. In the conventional substrate suction plate, a large number of suction holes are provided on the upper surface of the plate, and the substrate is fixed by vacuum suction.

  In recent years, for example, a liquid crystal display device is required to have a large screen, and accordingly, a substrate is becoming larger and thinner, but there are various types of substrate suction plates used in the conventional color filter manufacturing process. There is a problem. In particular, in order to perform thin film coating with a uniform film thickness so that coating unevenness does not occur in the coating process, it is necessary to maintain the flatness of the substrate with high accuracy. However, the flatness of the conventional substrate suction plate is high. It was difficult to achieve accuracy. Further, when the substrate is peeled off from the substrate suction plate, peeling electrification occurs due to friction with air, and the substrate becomes difficult to peel off from the substrate suction plate, and in the worst case, there is a problem that the substrate is cracked. . Furthermore, since the contact area between the substrate suction plate and the substrate is large, there is a problem that uneven drying occurs after coating due to the cooling action of the substrate suction plate.

The present invention solves the above-mentioned conventional problems, and the substrate suction plate used in the color filter manufacturing method and the color filter manufacturing apparatus can maintain the flatness of the substrate with high accuracy, and can be peeled and charged. It is an object of the present invention to provide a color filter manufacturing method and a color filter manufacturing apparatus capable of solving the problems of unevenness and drying unevenness.

  Therefore, the color filter manufacturing method of the present invention includes a coating process for applying a coloring photosensitive material, a pre-baking process for pre-baking the applied coloring photosensitive material, a cooling process after the pre-baking process, and a photomask. In the color filter manufacturing method including an exposure step for exposing and a developing step, in the coating step, the flatness in which a large number of concave portions are formed on the surface and suction holes are formed in a part of the numerous concave portions. In the cooling process after the pre-baking process, a large number of convex parts are formed on the surface in the cooling step after the pre-baking process, and the large number of convex parts are formed. A substrate suction plate for fixing the substrate by vacuum suction so as to reduce a contact area with the substrate while maintaining a flatness in which a suction hole is formed in a part of the substrate. Characterized by using.

  According to the present invention, by reducing the contact area with the substrate while maintaining the flatness of the substrate with high accuracy, a thin film coating with a uniform film thickness is enabled, and the problem of peeling charging is eliminated. The substrate can be easily peeled off. Furthermore, it is possible to prevent the occurrence of drying unevenness due to the substrate suction plate, and it is possible to prevent a positional shift during processing of the substrate on the plate.

FIG. 1A is a schematic front view, FIG. 1B is a plan view showing a part of the substrate suction plate of FIG. 1A, and FIG. C) is a cross-sectional view taken along line CC in FIG. 1B and viewed in the direction of the arrow. FIG. 2A shows another embodiment of the substrate suction plate of the present invention, FIG. 2A is a plan view showing a part of the substrate suction plate, and FIG. 2B is taken along line BB in FIG. 2A. It is sectional drawing cut | disconnected and seen in the arrow direction. It is a figure which shows the experimental result of the Example of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows one embodiment of a substrate suction plate used in the color filter manufacturing method and color filter manufacturing apparatus of the present invention, FIG. 1 (A) is a schematic front view, and FIG. 1 (B) is FIG. 1 (A). FIG. 1C is a cross-sectional view taken along the line CC of FIG. 1B and viewed in the direction of the arrow.

  The embodiment of FIG. 1 is a substrate suction plate suitably used in the coating process. In FIG. 1, the substrate suction plate 1 is provided with a plurality of suction holes 1a on the upper surface of the plate, and the suction holes 1a are suction paths. 2 is connected to a vacuum pump (not shown). The substrate 3 is held by the substrate transfer device 4 and is placed on the substrate suction plate 1 and fixed by vacuum suction as indicated by the arrows in the figure.

  A large number of circular recesses 1b are formed on the surface of the substrate suction plate 1, and the contact area with the substrate 3 is reduced while maintaining the flatness of the substrate suction plate 1. Examples of the method for forming the recess 1b include a method of covering the substrate suction plate 1 with a mask in which the shape of the recess 1b is patterned and performing a cutting process by sandblasting, or a method of performing an etching process. The suction holes 1a can be sufficiently adsorbed if formed with a diameter of 1 to 2 mm and an interval of 20 to 30 mm. The suction holes 1a are preferably disposed in the recesses 1b, but are not limited thereto. Absent. In addition, the material of the substrate suction plate 1 is preferably a material that can be easily processed, and is particularly preferably granite. In addition, the diameter φ of the recess 1b is preferably about 1 to 2 mm, the height h is about 30 μm, and the interval L is preferably about 1.5 to 4 mm.

  2 shows another embodiment of the substrate suction plate used in the color filter manufacturing method and color filter manufacturing apparatus of the present invention, FIG. 2A is a plan view showing a part of the substrate suction plate, and FIG. ) Is a cross-sectional view taken along the line BB in FIG.

  The present embodiment is a substrate suction plate that is suitably used in a cooling process after pre-baking before an exposure machine. In the cooling process, since the substrate is warmed in the previous pre-baking process, static electricity increases and the problem of peeling charging is great.

  Therefore, a large number of circular convex portions 1c are formed on the surface of the substrate suction plate 1 so as to reduce the contact area with the substrate 3 while maintaining the flatness of the substrate suction plate 1. Examples of the method for forming the convex portion 1c include a method in which a mask on which the shape of the convex portion 1b is patterned is placed on the substrate suction plate 1 and a cutting process is performed by sandblasting, or an etching method is performed. 2 is weaker than the structure of FIG. 1, the suction hole 1 a is preferably disposed in the convex portion 1 c particularly in a process where the suction force is required. However, the present invention is not limited to this. The material of the substrate suction plate 1 is preferably granite, and the diameter φ of the convex portion 1c is preferably about 1 to 2 mm, the height h is about 30 μm, and the interval L is preferably about 1.5 to 4 mm.

  Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications are possible. For example, in the said embodiment, although the shape of the recessed part 1b and the convex part 1c is circular, it is not specifically limited, such as a rectangle and a polygon.

  (Example) Next, the present invention will be described in more detail with reference to an example. When the substrate suction plate of FIG. 1 is used in the coating process, the diameter φ and the interval L of the recess 1b affect coating unevenness and peelability. In particular, when slot coating or die coating is used, the influence is great. Therefore, the influence of the diameter φ and the interval L of the substrate adsorption plate recess 1b on the releasability due to the substrate peeling charging and the coating unevenness of the substrate was examined by the following method, and is shown in FIG.

  After adsorbing a glass substrate (area: 300 mm × 400 mm, thickness: 0.7 mm, weight: about 228 g) on the substrate adsorption plate made of granite in the embodiment of FIG. 1, the adsorption is released and the substrate is 1 cm / sec. Measure the force required for peeling in the vertical direction at a speed of 5 mm using a weigh scale. If the load is not twice as large as the substrate weight, it is OK, and the load is twice as large as the substrate weight. In some cases, NG is shown in FIG.

  Next, the coating unevenness was determined by observing with a viewer using a glass substrate on which a color mosaic CB7001 manufactured by Fuji Film Olin was applied with a film thickness of 1.5 μm. The evaluation is shown in FIG. 3 as OK when no unevenness is observed, and as NG when unevenness is observed.

  From the results of FIG. 3, the releasability tended to be better when the diameter φ of the recesses was larger than the interval L between the recesses, and worsened when the diameter φ of the recesses was smaller than the interval L between the recesses. In addition, as for the coating unevenness, it is better that the diameter φ and the interval L of the recesses are small, and as the size increases, a round shape unevenness is observed in a portion corresponding to the position of the recess. However, when the concave portion is formed by sandblasting, the limit is about 1 mm, and preferably about 1.5 mm to 4 mm as described in the embodiment.

  1: substrate suction plate, 1a: suction hole, 1b: concave portion, 1c: convex portion, 2: suction passage, 3: substrate, 4: substrate transfer device

Claims (1)

An application step of applying a coloring photosensitive material;
A pre-baking step of pre-baking the applied color sensitive material;
A cooling step after the pre-baking step;
An exposure process of arranging and exposing a photomask;
Development process;
In a color filter manufacturing method including:
In the coating step, a substrate having a reduced number of contact areas with the substrate while maintaining flatness in which a plurality of recesses are formed on the surface and suction holes are formed in a part of the plurality of recesses is obtained by vacuum suction. Using the substrate adsorption plate to be fixed,
In the cooling process after the pre-baking process, the contact area with the substrate is reduced while maintaining the flatness in which a large number of protrusions are formed on the surface and suction holes are formed in a part of the plurality of protrusions. A color filter manufacturing method using a substrate suction plate for fixing the substrate by vacuum suction.

Images