JP2001318219A - Method for manufacturing color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a color filter for which the manufacture speed can be improved significantly and the cost can be drastically reduced by supplying a glass substrate in a continuous belt form and subjecting the substrate to the process of forming a color filter thereon, considering the trend for a thinner glass substrate of a liquid crystal display device. SOLUTION: The method for manufacturing a color filter includes the processes of continuously supplying a glass plate is in a belt form by a winding roll having a core radius larger than the minimum radius of a roll, which does not cause fracture of the glass sheet by bending stress. While the glass belt sheet is carried along a carrying passage, having the radius of curvature equal to or larger than the radius of curvature of the abovementioned minimum roll radius, the glass substrate is subjected to a series of steps for forming a color filter which includes the application of at least a photosensitive color composition, exposure to form a pattern, and development by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a color filter for a color display such as a liquid crystal display device, and more particularly to a color filter capable of dramatically increasing the production per unit time. The present invention relates to a method for manufacturing a filter.

[0002]

2. Description of the Related Art Liquid crystal display devices are widely used as television screens, display screens of personal computers, and various monitor display devices. For color display of a liquid crystal display device, it is general to use a color filter in which red, green, and blue color layers are formed in a fine pattern on a transparent glass substrate. Due to demands for larger screens and lower costs of liquid crystal display devices, various devices have been devised for the electrode substrate with a thin film transistor and the opposing electrode substrate with a color filter used in the liquid crystal display device. One of them is to increase the size of a glass plate serving as a substrate. For example, a color filter is manufactured on a glass substrate having a size of 1 m square or more by multiple attachment.

[0003] However, no matter how large the substrate is, the conventional method is a processing method for each glass plate, and this naturally limits the manufacturing speed.
There were limits to achieving cost reduction. The reasons are as follows: (1) Continuous processing is difficult even if glass plates are arranged one by one. Intermittent processing. (2) Acceleration time is required for conveyance due to repeated start and stop. However, a long acceleration time cannot be taken to make the uniform effective area long, so that the conveyance speed cannot be too high. (3) Indirect time is required for transferring and positioning each glass plate. That's what it means.

[0004] Further, when the size of the glass plate is increased to 1 m square, the glass plate easily bends, and the difficulty in handling in the manufacturing process increases. This causes a problem that the burden on manufacturing machinery and equipment increases sharply, and the amount of capital investment does not become ridiculous. Conventionally, each glass substrate has to be processed one by one because the glass itself lacks flexibility, is fragile in physical properties, and is easily broken. If glass is continuously supplied from a take-up roll in a strip shape and processing can be performed on it, it is expected that the production speed will be dramatically improved and the cost will be dramatically reduced.

On the other hand, the thickness of a glass substrate for a liquid crystal display device has been reduced to 1.1 mm several years ago and to 0.7 mm at present. This was for the purpose of reducing the weight of the liquid crystal display device and saving the cost of glass materials. However, in recent years, spacers for keeping two glass electrode substrates constituting a liquid crystal display device at a fixed interval (liquid crystal is sealed in this gap) are formed of glass beads or glass fibers made of organic resin columns or walls. It is changing to. Since the organic resin spacer has adhesiveness to two glass electrode substrates, it is advantageous that the liquid crystal display device is reinforced in terms of both structure and mechanical strength. Therefore, the thickness of the glass substrate can be reduced from 0.63 mm to about 0.50 mm, and this tendency is expected to further increase to about 0.30 mm in the future.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a glass substrate for a liquid crystal display device, in which the glass substrate is supplied in a continuous band, and a color filter is formed thereon. Another object of the present invention is to provide a color filter manufacturing method capable of achieving a dramatic improvement in production speed and a dramatic cost reduction.

[0007]

That is, the present invention relates to a method of forming a long glass strip having a thickness of 0.63 mm to 0.30 mm into a long core shape with a core radius larger than a minimum roll radius at which glass does not break due to bending stress. While continuously feeding in a belt form from a take-up roll having the glass ribbon while conveying the glass ribbon to a transport path having a radius of curvature equal to or greater than the radius of curvature of the minimum roll radius, A method for producing a color filter, comprising performing a series of color filter production steps including at least application of a photosensitive coloring composition, pattern exposure, development, and heat fixing treatment.

In the present invention, a series of color filter manufacturing steps including the above-described application of the photosensitive coloring composition, pattern exposure, development, and heat treatment are not repeated for one color, but are repeated continuously for the number of colors of the color filter. The method for producing a color filter may be carried out as follows.

Further, the present invention may be a method of manufacturing a color filter in which, after a series of color filter manufacturing steps, the color filter is cut for each color filter, or wound around a winding roll without cutting.

Further, the present invention is the method for producing a color filter according to claim 1 or 2, wherein a black matrix layer is formed at a position corresponding to a space between the color filter layers of each color prior to a series of color filter production steps. Is also good.

[0011]

Embodiments of the present invention will be described below. Consider a case where a glass substrate is formed into a long shape and wound around a cylindrical roll core. Find the minimum roll radius at which the glass substrate will not break. It is assumed that the width is arbitrary and the thickness is 0.5 mm. Radius of curvature R and bending stress σ in the bending direction
Is expressed as follows.

[0012]

(Equation 1)

Here, E is Young's modulus, ν is Poisson's ratio, and y is 1/2 of the plate thickness. We have previously determined that
"1737F" glass (commercial name: 1737F, manufactured by Corning Incorporated, USA) (Young's modulus E = 72.3 GPa, Poisson's ratio ν = 0.29)
Was wound around a cylindrical roll core having a diameter of 1 m (radius of curvature R = 0.5 m), and it was found that there was no problem. The bending stress σ generated on the back surface of the bent glass plate at that time was determined.

[0014]

(Equation 2)

That is, if the value of σ is 0.00395 GPa or less, the glass plate used does not break. If this is applied and converted to a plate thickness of 0.5 mm, a value of radius of curvature R = 5 m or more can be obtained. The above results were inferred from the results of an experiment in which a glass plate having a thickness of 50 μm was actually wound around a roll core having a radius of 0.5 m. That is, since the result is obtained only from the safety information, the radius R of the roll core is seen to be large. Specifically, for example, by making the thickness of the glass substrate thinner than 0.5 mm, reducing the value of Young's modulus E, or increasing the viscosity of the glass itself, for example, the radius of curvature R
= 2.5 m or less, a practical improvement is possible.

An embodiment of the present invention will be described below. The thinner the thickness of the glass strip used in the method of manufacturing a color filter of the present invention, the smaller the radius of the roll that can be wound. Therefore, a thickness of 0.63 mm or less is desirable. However, when the liquid crystal display device is assembled, mechanical strength as the device is required, so the thickness limit was set to 0.3 mm. The width of the glass strip is not particularly limited. For example, about 90 cm width is one guide. In other words, there is a problem of how much width the color filter production line can cope with glass.

When the glass substrate is wound around the take-up roll, the glass substrate is actually turned around in such a manner that a soft film, paper, foamed sheet or other cushioning material is interposed between the glass substrates. Is desirable because it does not damage the glass substrate. The glass substrate pulled out from the take-up roll is supplied to a color filter manufacturing process line, and its transport path is equal to or larger than the minimum roll radius at which the glass substrate does not break due to bending stress. It is necessary to pass through a conveyance path having a certain radius of curvature. Otherwise, the glass substrate will break during the processing.

The step of forming one color of the color filter includes at least application of a photosensitive coloring composition, pattern exposure, development, and heat-fixing treatment. There are steps such as drying, pre-baking before pattern exposure, washing after development, and cooling after heat fixing. Needless to say, these are appropriately selected and performed.

In the process of manufacturing a color filter for a glass substrate, it is desirable to set the time required for each step to be as equal as possible in order to smoothly carry out each processing step without stagnation. Nevertheless, in a process that seems to take a long time, for example, in the application process of the photosensitive coloring composition or in the pattern exposure of the applied film, a buffer that allows a certain amount of stagnation of the glass substrate before and after the process.・ It is practical to set up an agglomeration zone and take care not to hinder continuous processing.

Of course, the method of manufacturing a color filter according to the present invention is not limited to forming a single color layer. Since a normal color filter has three colored layers of red, blue and green, a series of steps for one color is performed in three steps.
The color filters may be manufactured at once by connecting them.

At the end of the color filter manufacturing process, the obtained color filter may be collected into a color filter having an appropriate size.
The obtained color filter may be wound again on a winding roll. Which one to select may be selected according to the manufacturing process of the liquid crystal display device in the next step.

Further, in the color filter for the liquid crystal display device, a black matrix layer is provided between the colored layers in order to increase the contrast of the display, in addition to the aforementioned colored layers of red, blue and green. Is what it is. The black matrix layer may be a single layer or a multilayer film of an inorganic material such as chromium metal or a chromium compound, or may be a film in which a black material such as carbon black or manganese dioxide is dispersed in a resin.

In the latter case, if a resin obtained by converting a resin into a photosensitive resin is used, it can be formed continuously on a belt-shaped glass plate by applying the manufacturing method of the present invention. In this case, in order to simultaneously form the black matrix layer and the three colored layers of red, blue and green, a series of processes for one color is formed as a series of four manufacturing process lines.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG.
It is shown below. <Example> The diameter of the core shaft is 6 m.
A glass belt 2 having a width of 0.5 mm and a width of 550 mm is prepared. From now on, the glass strip 2 is supplied to the color filter production line. 3 is a winding roll 1
Paper 4 inserted between the glass substrates 2 circling around
Is a roll 3 that collects the rolls. The glass substrate 2 passes through the nip roll 5, and is subjected to, for example, far ultraviolet irradiation to a cleaning device 6 including brush cleaning with a synthetic detergent, pure water rinsing, and the like.
Then, it passes through a draining / drying device 7 and its surface is cleaned.

Next, through a buffering / accumulating roll 8, a coating base roll 9 having a radius of 3 m for applying the photosensitive coloring composition is reached. Here, the photosensitive coloring composition is applied by a die coater machine 10. The coating thickness is
About 0.8 to 1.6 μm is appropriate. In the figure, reference numeral 11 denotes a pressing roll. In the pre-bake device 12 before exposure, 70
After pre-drying for 3 minutes at ℃, using the optical sensor 13,
The intensity of the transmitted light is measured to determine whether the thickness of the applied photosensitive coloring composition is appropriate.

Next, the glass substrate 2 is guided to the exposure device 15 via the second buffering / accumulating roll 14. The exposure device 15 is a one-shot exposure method for the entire surface, and pattern-exposes the glass substrate 2 intermittently by a step-and-repeat method to form a desired colored pattern as a latent image. The exposure amount for that purpose varies depending on the type of the photosensitive coloring composition used, but is required to be about 100 to 200 mJ / cm ² , and the time required for exposure is about 30 to 60 seconds. However, as in the conventional pattern exposure process, the indirect time required for stopping, waiting, loading into the exposure apparatus, positioning, and discharging from the exposure apparatus has been greatly reduced.

Thereafter, in the developing device 16, a developing process including shower development with an alkaline aqueous solution, subsequent washing with water, rinsing with pure water, etc., is performed.
The heating and fixing at 30 ° C. for 30 minutes were performed in the oven device 17. After passing through the third buffering / accumulating roll 18, the color filters were individually separated by a cutting machine 19. It is also within the scope of the present invention that the obtained color filter is wound around a winding roll and collected instead of the embodiment in the figure.

In the embodiment shown in FIG. 1, only one color processing step is performed. However, a similar manufacturing processing line is connected to manufacture a color filter in a three-color or four-line manufacturing processing line including a black matrix layer. Can also.

[0029]

The method for manufacturing a color filter according to the present invention comprises:
In view of the tendency of thinning the glass substrate of the liquid crystal display device, the glass substrate is supplied in a continuous band shape, and the color filter is formed thereon. According to the present invention, the production speed is remarkably improved, and the production quantity per unit time can be increased, for example, about 5 to 10 times. As a result, a color that can realize a dramatic cost reduction can be realized. This can be a method for manufacturing a filter.

According to the second aspect of the present invention, a color filter having three colors can be manufactured at a time by connecting three lines in the step of forming one color of the color filter. Further, according to the invention of claim 3, the obtained color filter is cut into a predetermined size, so that it can be adapted to a conventional production line for a liquid crystal display device.

According to the fourth aspect of the present invention, the obtained color filter is wound again on a winding roll, so that it can be applied to a liquid crystal display device manufacturing line of a continuous and integrated production line. Further, according to the invention of claim 5, it is possible to obtain a color filter in which a black matrix layer is interposed between the three colored layers.

[0032]

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a method for manufacturing a color filter of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 take-up roll 2 glass strip 3 collection roll 4 interleaf paper 5 nip roll 6 washing device 7 drying device 8 buffer / accumulation roll 9 coating base roll 10 die coater machine 11 holding roll 12 pre-bake device 13 optical sensor 14 second buffer / accumulation Roll 15 Exposure device 16 Developing device 17 Oven device 18 Third buffering / accumulating roll 19 Cutting machine

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AB13 DA18 DA20 FA28 2H048 BA11 BA45 BA48 BB02 BB14 BB42 2H091 FA02Y FA35Y FB06 FB08 FC12 FC23 LA12 LA15

Claims (5)

[Claims] Claims: 1. A 0.63 mm to 0.30 mm thick molded into a long shape
Is continuously supplied in a belt shape from a winding roll having a core axis radius larger than the minimum roll radius at which the glass does not break due to bending stress, and the radius of curvature of the minimum roll radius is equal to or greater than the minimum roll radius. While transporting the glass strip to a transport path having a radius of curvature, the glass strip is subjected to a series of color filter manufacturing steps including at least application of a photosensitive coloring composition, pattern exposure, development, and heat fixing. A method for producing a color filter, characterized in that: 2. The method for manufacturing a color filter according to claim 1, wherein a series of steps for manufacturing the color filter are repeatedly and continuously performed for the number of colors of the color filter. 3. The method for manufacturing a color filter according to claim 2, wherein the cutting is performed for each color filter after a series of color filter manufacturing steps. 4. The method for producing a color filter according to claim 1, wherein the series of color filter production steps is followed by winding on a take-up roll. 5. Prior to a series of color filter manufacturing steps,
3. The method for manufacturing a color filter according to claim 1, wherein a black matrix layer is formed at a position corresponding to a position between the color filter layers of each color.