JPH0317621A - Production of multicolor display device - Google Patents

Abstract

PURPOSE:To form transparent electrodes only on the color filters with good accuracy by successively forming a transparent conductive film and positive resist on the color filters and exposing the positive resist with light of a specific wavelength or below from the rear surface of the color filters. CONSTITUTION:The transparent electrodes 22 consisting of ITO and the color filters 23 are formed on a glass substrate 21. Further, the transparent conductive film 24 consisting of the ITO is formed by sputtering, vapor deposition, etc., thereon. The positive resist is exposed from the rear surface of the substrate by the light 27 via a UV transparent optical fiber 26 by using a high-pressure mercury lamp as a light source and using the color filters as a photomask. Namely, the spectral characteristics of the color filters are such that the transmittance is substantially zero at <=400nm and, therefore, the use of the color filter as the photomask for the light of <=400nm is possible. The positive resist is then developed to expose the ITO in the spacing parts between the color filters.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a multicolor display device using a color filter, and in particular, a method for manufacturing a multicolor display device using a color filter, in particular a method in which a driving electrode is provided on the color filter in order to reduce the driving voltage. The present invention relates to a method of manufacturing a multicolor display device.

[Summary of the invention]

In the present invention, a transparent conductive film is formed on a color filter, and then a positive resist is applied to the entire surface, and the positive resist is exposed from the back side of the color filter with light of 400 nm or less using the color filter as a photomask, and then developed and colored. By etching the transparent conductive film between the filter gaps,
Although this is a very simple method, it is possible to form driving electrodes only on the color filter with high precision.

[Conventional technology]

In recent years, liquid crystal display devices have become increasingly multicolored by combining them with color filters. Initially, a color filter was installed above the drive electrode, and the liquid crystal was driven through the color filter, but as the size and number of pixels increased, there was a strong demand for lower voltage drive, and the voltage loss due to the color filter was increased. To avoid this, methods are being developed to form driving electrodes on color filters. FIG. 4 shows an example of a multicolor liquid crystal display device using color filters. In FIG. 4, 41 is a transparent substrate made of glass, 42 is an electrode made of a transparent conductive film, and 43 is a color filter formed by electrodeposition, dyeing, printing, or the like. Note that in the case of the dyeing method and the printing method, 42 electrodes are not required. Reference numeral 44 denotes a driving electrode made of a transparent conductive film formed on the color filter in a matching pattern, and is formed in the process shown in FIG. In FIG. 5, 51 is a transparent substrate, 52 is a transparent electrode, and 53 is a color filter, which is formed by electrodeposition from a solution containing an electrodepositable polymer and a dye. Transparent conductive g! made of ITO by sputtering, vapor deposition, etc. on the entire surface of this substrate. 54 is formed. In FIG. 5 (bl), a resist 55 is applied to the entire surface of the transparent conductive crotch.

FIG. 5 (In Cl, the photomask 56 is aligned to match the color filter pattern, and the resist is exposed to light 57. In FIG. 5 + DI, the resist is developed to expose the transparent conductive film in the gap between the color filters. As shown in FIG. 5, the transparent conductive film in the gap between the color filters is etched, the remaining resist is peeled off, and drive electrodes 58 are formed only on the color filters.Returning to FIG. 4, the manufacturing method of the multicolor liquid crystal device will be explained. Then, the substrate 41 provided with the drive electrode 44 formed in this manner and the substrate 46 provided with the other drive electrode FfA 45 are separated.
By facing each other and sandwiching the liquid crystal 47, a multicolor liquid crystal display device is constructed. A multicolor liquid crystal display device designed in this way can be driven at low voltage without voltage loss due to color filters. (Problems to be Solved by the Invention) In the method for manufacturing a multicolor liquid crystal display device explained in FIG. 4 and FIG. As color filter patterns become more precise, photomasks become more difficult to produce without defects and become more expensive.Additionally, during exposure, the color filter and photomask must be closely spaced. Alignment is necessary, and the finer the pattern, the more technically difficult it becomes, the more complex the equipment and process become, and the higher the probability of defects. [Means for Solving the Problems] Therefore, the present invention With the aim of forming highly accurate driving electrodes on color filters in a simple process, we used the color fino letter itself as a photomask and used a transparent conductive film on the color filter as a means of pakuning the transparent electrode with self-alignment. By sequentially forming a positive resist and exposing the positive resist to light of 40 on- or less from the back of the color filter, only the positive resist in the gap between the color filters is exposed, and by developing and etching, only the top of the color filter can be accurately exposed. A transparent electrode is formed on the surface.

[Effect]

Currently, color filters for multicolor display devices often use the three primary colors of additive color mixture, that is, red, green, and blue, and their spectral characteristics are as shown in Figure 3. Below 400n, the transmittance is almost negligible. It is O. i.e. 400n
It can be used as a photomask for light below 1, indicating that self-alignment is possible. However, -a, the light source used to expose the resist is 40
There are few that generate only light of 0 nm or less. A mercury lamp or a metal halide lamp is commonly used as a light source. For example, the emission spectrum of a high-pressure mercury lamp is G-line (435 nm), H-line (405 nm), and I-line (365 na+) as shown in Figure 3. These three types are the main ones, and they vary in strength and range depending on the type.

Metal halide lamps often have a broad spread rather than a clear line spectrum. If there exists a light source that generates only i vA (365 nm), which is 400 nm or less, and hardly any light of 400 nm or more, the object of the present invention can be achieved by using that light source. However, when exposing the resist using a color filter as a photomask using a real light source, G-line (435nn
+)． hg (405nm) is also generated, and the blue filter in particular transmits light around 450nm, causing light leakage and exposing the resist on the color filter, which should not be exposed. The transparent conductive film on the filter will be removed.

Therefore, the present inventors added an ultraviolet transmitting optical filter that blocks light of 400n+m or more and has the spectral characteristics shown in Figure 3 to the conventional light source, and used the light that passed through this optical filter to cover the color filter with a photo mask. We discovered that by exposing with self-alignment, it is possible to completely eliminate the leakage of light passing through the color filter and obtain high resolution. According to this method, by simply adding an ultraviolet-transmitting optical filter to a conventional exposure light source, transparent electrodes can be formed very easily and accurately on color filters, making it extremely useful in practice. be. [Example] The present invention will be specifically explained below using Examples and Comparative Examples. (Example 1) FIG. 1 shows a sectional view of an example of a multicolor liquid crystal display device according to the present invention. 11 is a substrate made of glass, l2 is a transparent electrode made of ITO, 13 is a color filter, and a voltage is applied to the transparent electrode 12 in a solution containing an electrodepositable polymer and a dye.
Formed by electrodeposition. Reference numeral 14 denotes a driving transparent electrode made of ITO with a pattern formed on a color filter, which is manufactured by the process shown in FIG. In FIG. 2 fal, 21 is a glass substrate on which an ITOi3 bright t pole 22 and a color filter 23 are formed. Furthermore, spatter on top of that,
A certain transparent conductive film 24 is formed from IT○ by vapor deposition or the like. Figure 2), Posiresist 25 (OFPR
800 manufactured by Tokyo Ohka) is applied to the entire surface. In FIG. 2C, a high-pressure mercury lamp is used as a light source from the back side of the substrate, and the positive resist is exposed to light 27 through an ultraviolet transmission optical filter 26 using a color filter as a photomask. In this case, the ultraviolet transmitting optical filter may be either a thin film interference type or a type in which a visible light absorbing substance is mixed into glass. In FIG. 2 fdl, the positive resist is developed to expose the ITO in the gap between the color filters. In FIG. 2+el, the ITO in the gap between the color filters is etched, the remaining resist is peeled off, and the drive electrodes 28 are formed only on the color filters. This process does not require a precise photomask or precise alignment, making it simple and significantly reducing the defective rate.

Hereinafter, returning to FIG. 1 and continuing the explanation, the substrate 11 having the transparent electrode 14 formed in this manner and the substrate 16 having the other driving electrode 15 formed thereon are faced to each other, and the liquid crystal 17 is sandwiched between them. We created a multicolor liquid crystal display device. Although this multicolor liquid crystal display device was manufactured using a simple method, it was free from defects and was suitable for g-voltage drive. (Example 2) The transparent electrode 12 was directly produced on the foil substrate 11 by a dyeing method in which the color filter 13 in Example 1 was formed by patterning photosensitive gelatin and dyeing it with a dye. A multicolor liquid crystal display device was constructed by forming a transparent electrode 14 on a color filter in the same manner as in Example 1 except that a metal halide lamp was used as the light source for exposure, and the same effect as in Example 1 was obtained.

(Comparative example) When an attempt was made to form a transparent electrode on the color filter by directly applying light from a light source from the back of the color filter without using the ultraviolet transmitting optical filter 26 in Example 1, light of 400 nm or more appeared on the blue filter. The resist was exposed due to leakage, and the transparent electrode was no longer etched.

〔Effect of the invention〕

As explained above in detail in Examples and Comparative Examples, the method for manufacturing a multicolor display device according to the present invention does not require a precise photomask or accurate alignment as in the past, and the color filter is A highly accurate transparent electrode pattern can be formed on a color filter using self-alignment as a mask. Also, it requires 400r
Since it is only an optical filter that can produce light of +I++ or less, it is possible to mass-produce defect-free multicolor display devices suitable for low voltage drive very easily without complicating conventional manufacturing equipment. be.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a multicolor display device according to the present invention, and FIG.
a+ to tel are cross-sectional views showing the process for manufacturing transparent electrodes on color filters according to the present invention, FIG. 3 is a view showing the spectral characteristics of each filter and the brightness spectrum of the light source, and FIG. 4 is a conventional multicolor display device. Cross-sectional view of FIG. 5 [a) ~ tel
1 is a cross-sectional view showing a process for manufacturing a conventional transparent electrode on a color filter. 11, 16, 21, 41, 46, 12
, 14, 15, 28, 4413.23
, 43.53・ ・ ・ 17.47・ ・ ・ ・ ・ ・ ・24 54・
・ ・ ・ ・ ・ ・25.55・ ・ ・ ・ ・
・ ・26・ ・ ・ ・ ・ ・ ・ ・ ・56
・ ・ ・ ・ ・ ・ ・ 27.57・ ・ ・ ・ ・ 5l...Substrate 45. 58...Transparent electrode...Color filter...Liquid crystal...Transparent conductive film...Resist...Ultraviolet vA transmission optical filter Photomask light

Claims (4)

[Claims] (1) In a method for manufacturing a multicolor liquid crystal display device using color filters, [1] Step of forming a plurality of color filters on a transparent substrate; [2] Step of forming a transparent conductive film on the entire surface of the color filters; [ 3] Step of applying a positive resist to the entire surface of the transparent conductive film on the color filter [4] Step of exposing the positive resist to light of 400 nm or less from a light source on the back side of the substrate using the color filter as a photomask [5] Development A method for manufacturing a multicolor display device, comprising the step of: etching the transparent conductive film in the gap between the color filters to leave the transparent conductive film only on the color filters. (2) The light of 400 nm or less is produced by adding an optical filter to the light source that blocks light of 400 nm or more and transmits light of 400 nm or less. A method of manufacturing a color display device. (3) The method for manufacturing a multicolor display device according to claim 1, wherein the light source is a mercury lamp or a metal halide lamp. (4) forming a plurality of conductive layers in which the color filter is arranged insulated from each other on a substrate;
2. The method of manufacturing a multicolor display device according to claim 1, wherein the multicolor display device is selectively formed by electrodeposition.