JP2003029657A - Production method for display element and film substrate holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method for display element and a film substrate holder, with which processing such as printing can be surely performed without making the holder of a film substrate interfere an object for processing. SOLUTION: Processing such as printing, exposing, washing or sticking is applied to a film substrate 1 while using a film substrate holder 20A composed of a frame-shaped body 21 a little larger than the area of the film substrate 1 cut into prescribed dimension, an arm 31 for fixing at least four corners of the film substrate 1 on both terminal parts on a diagonal and a clip 35. The film substrate 1 is held so that a central portion (almost all the surface) can keep a planar state, a peripheral part thereof is held while being warped downwards, and no member protruded higher than a level L of the central planar part exists.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a display element and a film substrate holder, and more particularly to a method for manufacturing a display element using liquid crystal as a display medium, and a holder for a film substrate that holds the display medium.

[0002]

2. Description of the Related Art In recent years, a liquid crystal display device using a plastic film which is light and hard to break in place of glass has been attracting attention because of the advantage that a device having a relatively large area can be manufactured at low cost. However, when the film substrate is conveyed on the roller in the same manner as the glass substrate in the manufacturing process of the element, a problem that the film substrate is caught in the roller due to the bending easily occurs.

In order to avoid such troubles, a large number of film substrates are inserted into a cassette to perform batch processing.
Cleaning, dipping, annealing, etc. can be considered.
However, a film substrate whose one side is approximately 100 mm or more has a large amount of bending and is easily detached from the cassette, and this problem has not been solved yet. In addition, it is necessary to replace the film substrate with another holding tool during the single-wafer processing such as exposure, which is complicated.

Further, in order to convey / process the film substrates one by one, a method of fixing / holding the film substrates with a supporting plate or a frame-shaped jig can be considered. It is considered that if each film substrate is individually held, it can be held at an accurate position even if the film substrate is largely bent, and the film substrate can be easily transported.
Specifically, as shown in FIG.
The end of the film substrate 1 is sandwiched and held between the clip 11 (biased by the coil spring 12) installed corresponding to the corner and the projection 10a provided on the support plate 10.

However, in the holder shown in FIG. 14, when the film substrate 1 is kept in a flat state, the clip 11 projects above the flat line L, and, for example, a screen plate 15 and a squeegee 16 are used. In the process of screen-printing 17, the screen plate 15 does not come into contact with the film substrate 1 because the edge of the screen plate 15 comes into contact with the clip 11 (the part indicated by the symbol d in FIG. 14), and printing defects and imperfections are There was a problem that occurred. In addition to the screen printing, also in the developing process using a photomask, the rubbing process, the bonding process of a pair of film substrates, and the like, the processing member may come into contact with the clip 11.

On the other hand, as shown in FIG. 15, a hole 15a is formed in the edge portion of the screen plate 15 and the clip 11
Measures to prevent the interference of However, hole 15a
In some cases, foreign matter may easily adhere to the film substrate 1 and the film substrate 1 may be contaminated, and further, the balance of the screen plate 15 may be lost and the screen plate 15 may be easily distorted.

Also, many foreign substances adhere to the edges of the film substrate 1 when they are cut, and these foreign substances may contaminate processing members such as photomasks and screen plates during various processing steps. It is also necessary to prevent

Furthermore, it is necessary to attach and detach the film substrate to and from the holder when carrying out various processes such as transportation, heat treatment, printing, cleaning, and development.
It is complicated, the production efficiency is greatly reduced, and the film substrate may be damaged.

Therefore, an object of the present invention is to provide a method for manufacturing a display element and a film substrate holding method, in which a holder for the film substrate does not interfere with an object for processing, and processing such as printing can be reliably performed. To provide the ingredients.

Another object of the present invention is to provide a method of manufacturing a display element and a film substrate holder which can prevent foreign matters adhering to the edge of the film substrate from contaminating the processing member as much as possible.

Still another object of the present invention is to provide an efficient method of manufacturing a display device capable of performing a series of steps while holding a film substrate on a holder.

[0012]

In order to achieve the above object, the method for manufacturing a display element according to the first invention is a method for manufacturing a display element using a film substrate cut into a predetermined size, and a holder is provided. A step of keeping the central part of the film substrate in a flat state by holding at least both ends of the film substrate in a state of being bent downward from the central flat part, and bringing an object into contact with the central flat part. It is characterized in that processing including it is performed.

The processing is a printing processing for printing a printing material by bringing a plate close to a film substrate, a coating processing for applying a coating material by bringing a rotor or a coater close to a film substrate,
At least one of an exposure process including a step of exposing a film substrate to a photomask in proximity, a rubbing process of rubbing a film substrate with a rubbing member, and a substrate bonding process of superposing another film substrate on one film substrate. Is.

The film substrate held by the holder may be heat-treated, or the liquid may be brought into contact with the film substrate held by the holder.

According to the above-described manufacturing method of the first aspect of the present invention, since the film substrate is kept substantially flat over the entire surface and at least both end portions are held in a state of being bent below the flat portion, the flat surface is maintained. When a treatment including a step of bringing an object (for example, a screen plate, a photomask, etc.) into contact with the flat portion of the film substrate without causing a part of the holder to project above the level of the state, the object is Since there is no member that interferes with the object, the contact of the object is not incomplete. Therefore, the necessary processing can be performed reliably and completely. In addition, since the cut edge of the film substrate is located below the flat portion on which the processing is performed, it does not come into contact with the object for processing, and the foreign matter adhering to the edge is the object. Contamination is prevented as much as possible. Further, it becomes possible to perform various processes and final substrate bonding with the film substrate held by the holder.

A method of manufacturing a display element according to the second invention is
In a method of manufacturing a display element, comprising a display medium sandwiched between a pair of film substrates cut into a predetermined size, at least one film substrate is mounted on a holder, and the surface of the film substrate is mounted on the holder. Is subjected to a process including a step of bringing an object into contact with the film substrate, and the film substrate subjected to the above process and the other film substrate are superposed and bonded to each other.

According to the manufacturing method of the second aspect of the invention described above, various steps for bringing an object for treatment into contact with the surface of the film substrate with at least one of the film substrates still mounted on the holder, and the final step. Since processing is performed up to substrate bonding, it is not necessary to attach and detach the film substrate to and from the holder in each step, and the display element can be efficiently manufactured.

The film substrate holder according to the third invention is
A film substrate holder for holding a film substrate cut to a predetermined size, wherein the frame member holds the central portion of the film substrate in a flat state, and at least both ends of the film substrate are the central flat portion. And a fixing member that is fixed in a state of being bent downward.

According to the film substrate holder according to the third aspect of the present invention, the central portion of the film substrate is kept flat,
Since both ends are fixed in a state of being bent downward from the central plane portion, when performing processing including the step of bringing the object into contact with the central plane portion of the film substrate, the object must be surely in contact with the central plane portion. become. In addition, the cut edge of the film substrate is located below the central plane, does not contact the object for processing, and prevents foreign matter adhering to the edge from contaminating the object as much as possible. Can be prevented. Furthermore, it becomes possible to continuously process various processes for the central plane portion while the film substrate is attached to the holder.

In the film substrate holder according to the third aspect of the invention, it is preferable that the frame and the fixing member are located at the same height as or below the central plane portion of the film substrate when holding the film substrate. It is possible to surely prevent the interference with the object for use. Further, it is preferable that the frame body is composed of a frame-shaped frame corresponding to the size of the film substrate, the weight of the holder is reduced, and substantially the entire surface of the film substrate can be effectively pressed from the frame side by a press plate or the like. it can. Further, it is preferable that the fixture fixes the film substrate at least at both ends on the diagonal of the film substrate. It is possible to hold the film substrate with a proper tension.

Further, it is preferable that the film substrate holder is provided with a member for applying outward tension to the film substrate. The film substrate may be loosened due to thermal expansion, but such looseness can be corrected by applying tension.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a method for manufacturing a display element and a film substrate holder according to the present invention will be described below with reference to the accompanying drawings.

(Film Substrate Holder, See FIGS. 1 to 5) FIGS. 1A and 1B show a schematic structure of the film substrate holder according to the present invention. The holder 20 is for holding the film substrate 1 cut into a predetermined size,
A frame-shaped frame body 21 corresponding to the size of the film substrate 1 (slightly larger than the area of the film substrate 1), and a fixture 25 for fixing the film substrate 1 at both ends on a diagonal line.
It consists of and.

The fixture 25 holds the peripheral portion of the film substrate 1 and applies a tension to the film substrate 1 in the direction of arrow X (that is, in a direction away from each other on a diagonal line), so that the film substrate 1 is appropriately tensioned. Have. The film substrate 1 may expand and loosen during heat treatment,
Slack can be prevented by applying elastic tension.

Since the film substrate 1 is cut into a quadrangular shape, it is appropriate that the fixture 25 fix each vertex (both ends on the diagonal line) of the film substrate 1 as shown in FIG. 1 (A). is there. Further, as shown in FIG. 1B, a fixture 25 may be added so as to fix the side portion of the film substrate 1.

As the material of the holder 20, destruction, deformation, or the like in the manufacturing process of the liquid crystal display element 100 described below.
It is required that the material does not deteriorate, and a material having properties such as acid resistance, alkali resistance, heat resistance and impact resistance is selected. A metal material such as aluminum, stainless steel, or titanium, a ceramic material, a resin material such as an acrylic resin, a polycarbonate resin, a phenol resin, or a polyether ether ketone resin can be used. A coating for improving chemical resistance may be applied to these surfaces.

More specifically, FIG. 2 shows a holder 20A according to the first embodiment. This holder 20A
Is provided with an arm 31 rotatably at an end of the frame body 21 about a pin 32 as a fulcrum, and a clip 35 on the arm 31 with a pin 3
It is rotatably attached with 6 as a fulcrum. The arm 31 has a tip portion curved inward, and is biased outward by a coil spring 33. Also, clip 3
5 is biased by a coil spring 37 so as to be crimped to the curved portion of the arm 31.

The periphery of the film substrate 1 is an arm 31.
It is held by the holder 20A in a state in which it is sandwiched between the tip curved portion and the clip 35. At this time, the film substrate 1 is held so that the central portion (almost the entire surface) thereof is kept flat, and the peripheral portion is fixed in a state of being bent downward along the curve of the arm 31. In this holder 20A, there is no member protruding above the level L of the central plane portion.
Further, the fixing force is applied by the coil spring 37, and the tension for keeping the flat state is applied by the coil spring 33. In addition to the coil springs 33 and 37, the elastic biasing force may be applied by utilizing the elasticity of rubber or resin material.

FIG. 3 shows a holder 20B as a second embodiment.
Indicates. This holder 20B is a rod 4 fixed to a frame.
1, an arm 43 is provided movably in the arrow X direction and the opposite direction (that is, a direction along the rod 41) via a bracket 42, and a clip 45 is rotatably attached to the arm 43 with a pin 46 as a fulcrum. Is. The arm 43 has a tip portion curved inward, and is urged outward (direction of arrow X) by a coil spring 44 mounted on the rod 41. The clip 45 is biased by a coil spring 47 so as to be pressed against the curved portion of the arm 43.

With this holder 20B, the film substrate 1
Is held in the same manner as in the first embodiment, and the film substrate 1 is stretched by the coil spring 44 with an appropriate tension.

FIG. 4 shows a holder 20C as a third embodiment.
Indicates. In this holder 20C, a fixing portion 52 having a curved portion is provided at an end of a frame body 51, and a clip 55 is rotatably attached with a pin 56 as a fulcrum.
The clip 55 is biased by a coil spring 57 so as to be pressed against the curved portion of the fixed portion 52.

With this holder 20C, the film substrate 1
Is held in the same manner as in the first and second embodiments.
However, the tension applying means for the film substrate 1 is omitted. The tension applying means may be omitted as in the third embodiment for a film substrate in which sagging due to thermal expansion is not a serious problem.

Here, a preferred holding mode of the film substrate 1 will be specifically described with reference to FIG. The size of the film substrate 1 is, for example, 300 × 400 mm and the thickness is 100 μm, and the radius of curvature of the curved portion held by the arm 43 and the clip 45 is 3 mm or more. If the radius of curvature is less than that, the substrate is likely to be cracked or cracked.

The area E pressed by the tip of the clip 45 is preferably in the range of 1 to 15 mm. When the width is smaller than this, the substrate is scratched and easily cracked, and when the width is larger than this, a wasteful portion of the substrate used as a display element increases. The bending margin F of the film substrate 1 is preferably in the range of 3 to 20 mm. If it is narrower than this, it tends to come off, and if it is wider than this, there are many wasted parts of the substrate.

The tensile strength for providing tension to the film substrate 1 is preferably in the range of 0.2 to 10 Newtons. If it is too weak, it becomes difficult to maintain the planar state, and if it is too strong, the non-holding portion of the substrate may be damaged.

As in the first, second and third embodiments,
The method of fixing the film substrate 1 with the clips 35, 45, 55 is easy when the substrate is attached and detached, and is effective when the substrate is attached and detached during the manufacturing process. However, if the film substrate 1 is attached to the holder 20 (20A, 20B, 20C) and the whole manufacturing process is performed, the film substrate 1 may be bonded to the holder 20.

5A and 5B show a holder 20D for adhering and holding the film substrate 1 as a fourth embodiment. This holder 20D is provided with a fixed portion 62 having a curved portion at the end of a frame 61. Whether the film substrate 1 is attached to the fixed portion 62 via a double-sided adhesive tape 63 (see FIG. )), And affix with the single-sided adhesive tape 64 (see FIG. 5B).

In this way, the film substrate 1 is held by the holder 20D.
In the case of adhering to, the film substrate 1 may be adhered while being pulled by a force of 2 to 30 Newton. It is possible to prevent loosening due to expansion during heat treatment to some extent. The film substrate can be removed from the holder by cutting the adhesive portion after completing all the manufacturing steps. In addition,
As a holder for bonding and holding the film substrate,
The film substrate may be detached from the holder without cutting the film substrate by using a weakly adhesive tape that is detachable.

(Structure of Liquid Crystal Display Element, See FIG. 6) A liquid crystal display element can be efficiently manufactured using the holder 20. FIG. 6 shows an example of the manufactured liquid crystal display element. Although the liquid crystal display device 100 is a single layer, it can be stacked in a plurality of layers to provide, for example, full color display.
It is also possible to manufacture a liquid crystal display device having a layer structure.

In FIG. 6, reference numerals 1 and 1 denote two light-transmitting resin film substrates facing each other. As such a film substrate, for example, polyether sulfone resin, polyethylene terephthalate resin, polycarbonate resin or the like is used, and any thin and flexible film can be used.

Transparent electrodes 2 are formed on the surface of the film substrate 1 so as to face each other. The display element 100 has a simple matrix electrode structure in which a plurality of band-shaped transparent electrodes 2 are opposed to each other at right angles.
Although the electrode formation process described later shows a simple matrix electrode structure, an active matrix electrode structure may be adopted instead. As the transparent electrode 2, a metal thin film such as indium tin oxide (ITO), indium zinc oxide (IZO), aluminum and silicon, a photoconductive thin film such as amorphous silicon and bismuth silicon oxide (BSO) can be used.

A liquid crystal layer 5 is sandwiched between two film substrates 1 and 1. A liquid crystal display device 100 having the configuration shown in FIG.
The liquid crystal material typically used in, for example, polymer dispersion type liquid crystal, cholesteric nematic phase transition type liquid crystal, liquid crystal that selectively reflects light in the visible wavelength region (cholesteric liquid crystal, chiral material in which chiral material is added to nematic liquid crystal Such as nematic liquid crystal). In the case of the selective reflection type liquid crystal display element 100, a light absorbing function is imparted to the lower film substrate 1 (the substrate itself is made black, black paint is applied, or a black sheet is attached).

The film substrate 1 is further provided with an insulating film 3 for preventing a short circuit between the electrodes 2 facing each other and an alignment control film 4 for controlling the direction of molecular alignment of liquid crystals.
Further, a bead spacer 6 for keeping the liquid crystal layer 5 at a predetermined thickness and a resin structure 7 for preventing the peeling of the substrates 1 and 1 are arranged between the film substrates 1 and 1, and the liquid crystal layer 7 is provided on the outer periphery. A sealing wall 8 for sealing the layer 5 is provided. Only one of the bead spacer 6 and the resin structure 7 may be arranged.

As the insulating film 3, an inorganic material such as silicon oxide or an organic material such as polyimide resin or epoxy resin is used. A polyimide resin is mainly used as the orientation control film 4.

As the bead spacers 6, fine glass fibers, ball-shaped silicate glass, inorganic substances such as alumina powder or organic synthetic spherical fine particles are used. Also,
It may be a resin-coated spacer.

Various resin materials can be used for the resin structure 7, and an organic material which does not chemically react with the liquid crystal material and has appropriate elasticity is preferably used. It may be any of a thermoplastic resin, a thermosetting resin, and a photocurable resin. Further, the seal wall 8 can be made of the same material as the resin structure 7. The same material may be used in combination, or different materials may be used.

(Outline of Manufacturing Method, See FIGS. 7 to 9) An outline of a method of manufacturing the liquid crystal display device 100 will be described. FIG. 7 is a flowchart showing the order of steps, and FIGS. 8 and 9 are schematic explanatory diagrams thereof.

First, the film substrate 1 is washed with various washing liquids and water and dried. Then, a transparent electrode film 2'which becomes the electrode 2 is formed (see FIG. 8A), a photoresist is applied, and baking is performed. The photoresist is applied by using a spin coater, a roll coater, a die coater, a spray, or the like. After that, place a mask, expose, develop,
Rinse the photoresist with water. Further, the remaining photoresist is baked again, the electrode film 2'is etched, washed with water, and the photoresist is removed. Further, it is washed with water and a washing liquid, and dried. Thereby, the film substrate 1 provided with the electrode 2 is obtained (see FIG. 8B).

Next, the insulating film 3 is applied onto the electrode formation surface of the film substrate 1 (see FIG. 8C) and baked. Further, the alignment control film 4 is applied thereon (see FIG. 8D), baked and subjected to rubbing treatment. The rubbing treatment may be performed on the alignment control film 4 on at least one of the substrates 1 and may be omitted altogether.

Next, spacers 6 are scattered on one of the film substrates 1 (see FIG. 8E), and if necessary (for example, a fixing spacer coated with a thermoplastic resin is fixed to the substrate). (If you want to make it). Further, the seal wall 8 is printed (see FIG. 8 (F)) and baked to be in a semi-cured state. The resin structure 7 is printed on the other film substrate 1 '(see FIG. 8G) and baked. The spacers 6 may be scattered or the seal wall 8 or the resin structure 7 may be formed on either the film substrate 1 or 1 '.

Next, one film substrate 1 is placed on the vacuum suction table 70, the other film substrate 1'is overlaid thereon and pressed using the plate 75 to perform bonding (FIG. 9 ( See A)). After that, the film substrate 1,
The liquid crystal 5 is injected between 1'by, for example, a vacuum injection method (see FIG. 9B). A predetermined amount of the liquid crystal 5 is dropped on the lower film substrate 1 before bonding, and the bonding is performed from one end to the other end of the lower substrate 1 while pressing the upper substrate 1'with a roller. It is also possible to adopt a method of sequentially overlapping with.

(Processing in Each Step, See FIGS. 10 to 13) In the above various steps, processing is performed with the film substrate 1 attached to the holder 20. For example, FIG. 10 shows a state in which a photoresist exposure step is being processed.
Is a photomask placed close to the film substrate 1,
Reference numeral 82 is a light source for exposure. FIG. 11 shows a film substrate 1
Shows a state in which the step of applying the insulating film by bringing the rotor 85 close thereto is being processed. If a rubbing roller is used instead of the rotor 85, the rubbing process is performed in the same manner as in FIG.

FIG. 12 shows, for example, a step of screen-printing a resin structure, in which a screen plate 91 is arranged on the film substrate 1 and a squeegee 92 is used to stretch the resin material 93 for printing. Further, FIG. 13 shows a step of laminating the film substrates 1 and 1 ′ described with reference to FIG.

When various processes are performed by using the holder, the film substrate can be maintained in a flat state over almost the entire surface and can be held in a state in which the peripheral portion is bent downward from the flat portion. The holder does not project above the level, and the screen plate is
In the process of contacting a processing object such as a photomask,
Since there is no member that interferes with the object, the object surely contacts.

Further, the cut end of the film substrate does not come into contact with the object to be treated, and foreign matter attached to the end is prevented from contaminating the object as much as possible.
Then, it is possible to process all the steps shown in FIG. 7 with the film substrate attached to the holder.

Since the frame body 21 of the holder 20 has a frame shape slightly larger than the film substrate 1, the vacuum suction table 70 and the pressing plate 75 can be positioned inside the frame body 21 and the bonding step. Can be processed without any trouble. Furthermore, a general-purpose machine can be used as a processing device such as a printing machine or a coater, and film substrates of various sizes can be processed.

(Other Embodiments) The method for manufacturing a display element and the film substrate holder according to the present invention are not limited to the above embodiments, but can be variously modified within the scope of the invention.

In particular, the detailed configuration and shape of the holder are arbitrary, and the liquid crystal display element may have a configuration other than that shown in FIG. Further, the manufacturing process may include a process other than the process shown in FIG. 7, or a part of the process may be omitted.

[Brief description of drawings]

FIG. 1 is a plan view showing a schematic configuration of a film substrate holder according to the present invention.

FIG. 2 is an elevational view showing a main part of the first embodiment of the film substrate holder.

FIG. 3 is a sectional view showing a main part of a second embodiment of a film substrate holder.

FIG. 4 is a sectional view showing a main part of a third embodiment of a film substrate holder.

FIG. 5 is a cross-sectional view showing a fourth embodiment of the film substrate holder.

FIG. 6 is a sectional view showing an example of a liquid crystal display element.

FIG. 7 is a flowchart showing manufacturing steps of the liquid crystal display device.

FIG. 8 is an explanatory view showing a manufacturing process of the liquid crystal display element.

FIG. 9 is an explanatory view showing the manufacturing process of the liquid crystal display element, continued from FIG.

FIG. 10 is a schematic cross-sectional view showing an exposure process.

FIG. 11 is a schematic cross-sectional view showing a coating process.

FIG. 12 is a schematic cross-sectional view showing a printing process.

FIG. 13 is a schematic explanatory view showing a bonding step.

FIG. 14 is a schematic explanatory view showing an example of a printing process using a conventional holder.

FIG. 15 is a schematic cross-sectional view showing another example of a printing process using a conventional holder.

[Explanation of symbols]

1 ... Film substrate 20 (20A, 20B, 20C, 20D) ... Holder 25 ... Fixing device 33, 44 ... Coil spring (tensioning member) 35, 45, 55 ... Clip 63, 64 ... Adhesive tape

Claims (3)

[Claims] 1. A method of manufacturing a display device using a film substrate cut into a predetermined size, wherein a central part of the film substrate is kept flat by a holder, and at least both end parts of the film substrate are the central planar part. A method of manufacturing a display element, characterized in that the display element is held in a state of being bent downward more than that, and a treatment including a step of bringing an object into contact with the central plane portion. 2. A method of manufacturing a display element comprising a display medium sandwiched between a pair of film substrates cut into a predetermined size, wherein at least one film substrate is mounted on a holder, and the holder is mounted on the holder. A process including a step of bringing an object into contact with the surface of the film substrate in, and performing a process of laminating and bonding the processed film substrate and the other film substrate, Production method. 3. A film substrate holder for holding a film substrate cut to a predetermined size, comprising: a frame body for holding the central portion of the film substrate in a flat state, and at least both end portions of the film substrate. A fixing member for fixing the film substrate in a state of being bent downward from the central plane portion, and a film substrate holder.