JPS63159807A - Production of color filter - Google Patents

Abstract

PURPOSE:To obtain a color filter with black stripes by patterning dyed layers at prescribed interval on a transparent substrate, coating a positive type photoresist thereon, exposing the resist by light except the light transmitted through the dye parts from the rear face of the substrate and developing the resist, then lifting off a thin light shieldable film. CONSTITUTION:A gelatin layer 2 is provided on a transparent glass plate 1 and the dye parts of red, green and blue are formed thereon except the regions 3 for the black stripes. The dye parts are isolated by the regions 3. The positive type photoresist 4 is provided on the gelatin 2 and is exposed from the rear face of the substrate 1 by a high-pressure mercury lamp using a filter which absorbs or transmits the light of the wavelength region to be transmitted by the dye parts R, B, G. The positive resist of the undyed regions 3 is removed when such resist is developed. The thin light shieldable film 6 consisting of Cr, etc., is then deposited on the surface and the positive resist 4 is striped by a lifting off method, by which black stripes 7 are formed. The cost of the color filter is reduced by this method.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a method of manufacturing a color filter for use in color liquid crystal TVs and the like, and particularly relates to a method of manufacturing a color filter with black stripes.

[Prior Art] Liquid crystal display elements equipped with color filters for the three primary colors of red, green, and blue are conventionally known.
Alternatively, when forming an amorphous silicon TPT (thin film transistor), a so-called black stripe is provided in order to prevent characteristic deterioration of the TPT due to light irradiation.

[Problems to be Solved by the Invention] In the conventional method of forming black stripes, the step of forming the black stripes was performed separately from the step of forming the color filters. Therefore, the number of steps increases accordingly, and the work of fine-tuning, such as aligning the black stripes and color filters, increases. In addition, an expensive photomask for forming the black stripes is also required in addition to the one for the color filter, and these factors are reflected in the price of the color filter, making it expensive.

[Means for Solving the Problems] The present invention is intended to solve the problems in the above-mentioned conventional example, and involves forming a pattern of dyed portions at predetermined intervals on a transparent substrate, and then applying a positive type photo to the entire surface. A resist is applied, exposed to light from the back side of the substrate excluding the light that passes through the dyed area, developed, and then a light-shielding thin film is formed on it.The light-shielding thin film on the resist is removed by a lift-off method. This makes it possible to form a color filter with black stripes.

[Example 2] In FIG. 2, a dyeable resin layer 2 such as gelatin is provided on a transparent substrate 1 such as glass, and except for the black stripe area 3, red dyed area R11 color dyed area G, blue dyed area The dyed areas B are each dyed differently. The method for dyeing is, for example, by repeatedly forming a gelatin layer as the dyeable resin layer 2 on the substrate 1, patterning a photoresist on the gelatin layer, and then dyeing the gelatin layer.

During this patterning, portions R, G, and B of each color are formed at intervals of a predetermined area 3. A positive photoresist 4 is coated and dried on this dyeable resin layer 2, and then dyed portions R, G, and B of the photosensitive wavelength range of the positive photoresist 4 are transmitted from the back side of the substrate 1. Cuts light in the wavelength range,
That is, exposure is performed using a high-pressure mercury lamp of a mask aligner using a filter 5 that absorbs or reflects light. FIG. 5 shows a graph showing the spectral transmittance of each of the red dyed part R5, the color dyed part G1, and the blue dyed part B.

As can be seen from this, a short-pass filter that cuts light of 400 nm or more and passes light of less than 400 nm may be used. As the positive resist 4 that can be used in this case, for example, Nagase Positive Resist 809 (trade name)
The spectral sensitivity is as shown in FIG. Therefore, this positive resist 4 is exposed to light excluding the light transmitted through the dyed portions R and GSB. When it is then developed, the positive resist remains on the dyed portions R and GSB, and the positive resist in the undyed portion of the area 3 where the black stripe is to be formed is removed (FIG. 3). In this state, a light-shielding thin film 6 of approximately 1100 nm of chromium Cr or aluminum AI is applied by a method such as sputtering (Fig. 4), and then the positive resist 4 is peeled off using a lift-off method to remove the light-shielding thin film 6 on the positive resist. A black stripe 7 is formed (FIG. 1).

In the above example, the color filter has three colors of red, green, and blue, but the selection of colors is not limited to this.
Any color may be used as long as it absorbs , and the number of colors is not limited to three.

Further, in the above embodiment, an example was shown in which the dyeable resin was formed on the entire surface of the substrate, but it goes without saying that the present invention can also be applied to a color filter in which the dyeable resin is left in islands for dyeing.

[Effects of the Invention] According to the method of manufacturing a color filter according to the present invention, patterning of black stripes can be performed by exposing the dyed portion of the color filter as a mask.
Only alignment between the black stripe and the color filter is required, and an expensive photomask for the black stripe is also no longer necessary, making it possible to reduce the price of the color filter.

[Brief explanation of the drawing]

The drawings show an embodiment of the invention, and FIG. 1 is a sectional view of a color filter formed according to an embodiment of the invention, and FIGS. 2, 3, and 4 are sectional views showing the manufacturing process, respectively. FIG. 5 is a graph showing the transmission wavelength characteristics of the dyed portion. DESCRIPTION OF SYMBOLS 1...Substrate, 2...Dyeable resin layer 4...Positive photoresist 6...Light-shielding thin film 7...Black stripe R...Red dyed part G...Green dyed part B...Above the blue stained area

Claims (1)

[Claims] A dyed area is formed on a transparent substrate excluding the black stripe area, and a positive photoresist is applied thereon and dried. After exposure with light excluding light in the wavelength range that is transmitted by the photoresist and development, a light-shielding thin film is further formed on the photoresist, and then the light-shielding thin film on the photoresist is removed by a lift-off method to form the black stripe. A method for producing a color filter, the method comprising forming a black stripe in a color filter area.