JP2009063608A - Method for manufacturing color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a flexible color filter formed on a film basic material 101 easily without increasing the number of processes and scale of facilities when manufacturing the color filter by a photolithography method on the film basic material 101 supplied from a winding roll. <P>SOLUTION: In the method for manufacturing the color filter, a solvent of photosensitive resist in an effective area 110 is dried by sandwiching a non-effective area 111 of the film basic material 101 between structural bodies divided into upper and lower parts by a batch type vacuum drying device having a mechanism for applying the liquid-like photosensitive resist intermittently by limiting only to the effective area 110 of the color filter of the film basic material 101 by a coater 102 and sandwiching the film basic material 101 between the structural bodies from above and below. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a manufacturing method for producing a color filter for electronic paper or a liquid crystal display device on a flexible base material such as a long plastic film with high production efficiency by a photolithography method.

In recent years, flat panel displays have been used for TV monitor applications and mobile applications in terms of energy saving, space saving, and portability. Various flat panel display display methods such as liquid crystal display devices, electronic paper, and OLED have been developed.
In particular, in mobile applications, there is a demand for plasticization from the viewpoint of impact resistance that does not break even when dropped while carrying, light weight, and thinning. In addition, the wall-hanging type also has a demand for a flexible display from the viewpoint of installing the display on a columnar column.

  Color filters used in flat panel displays are also required to have high color reproducibility and visibility. For TV monitors, red, green, and blue colors are used, and for mobile applications, red, green, and blue are used. Transparent pixels called white for increasing brightness and those in which a pattern in which a filler is dispersed in a transparent resin to give light scattering are used.

  As a method for producing a color filter, a photolithography method, an ink jet method, a printing method, and the like have been proposed. The ink jet method is capable of forming a pattern by ejecting Red, Green, and Blue ink only to a predetermined portion on a black matrix formed by a photolithographic method, so that the material use efficiency is high and the number of photomasks used can be reduced. It is expected as a simple manufacturing method. However, the diameter of ink droplets of the current inkjet is about several tens of μm, and the landing accuracy is as low as about several μm, so that it is difficult to develop into high-definition color filters for mobile use.

  The printing method includes a method of transferring the pattern to the substrate using a resin relief plate, or transferring the pattern to the substrate via the blanket after applying ink on the blanket and removing unnecessary non-patterned ink with the removal plate. A reversal printing method is known.

Each method can easily form a precise patterning and does not involve a development step unlike the photolithographic method, and therefore, development to OLEDs in which the removal of moisture is required has been studied. Since the printing method forms a pattern through a soft base material that easily swells with a solvent such as a resin plate or a blanket, there is a problem in controlling positional accuracy. (See Patent Document 1)
The photolithography method has been established as the most stable technique for forming color filters on glass. Liquid photosensitive resists have been continuously improved, and an apparatus for stably producing on a large glass substrate exceeding a meter is provided.

As a base material for forming a display, as a plastic base material other than a glass substrate, a single-wafer plastic substrate or a long plastic film has been proposed.
It is necessary to change the method for transporting the substrate and the method for forming each pattern of the flat panel display depending on the form of the substrate. Single-wafer plastic substrates can be used in conventional glass substrate manufacturing processes, but long plastic films can be unwound, wound, and continuously fed between them. A technique different from a conventional single-wafer glass substrate is required, such as management of a pattern formation area and management of each manufacturing process.

  As a method of forming a color filter on a long plastic film substrate by photolithography, a method of forming a pattern by exposure, development, and hardening after laminating a dry-film photosensitive resist on the substrate has been proposed. However, it is necessary to make a photosensitive resist into a dry film, it is difficult to finely adjust the chromaticity and film thickness, and it is not easy to change the color by changing the pigment type. There is a problem that the resist outside the pattern formation area is not used for laminating and the material efficiency is low. In addition, a dry film forming device, a laminating device consisting of continuous conveyance, an exposure device consisting of intermittent conveyance, a developing device consisting of continuous conveyance, a film forming device consisting of continuous conveyance, and a plurality of manufacturing apparatuses are required, and a wide installation space is required. There existed a problem of becoming (refer patent document 2).

  In addition, a method in which a liquid photosensitive resist is directly applied to a plastic film substrate, dried in a heat drying oven, and then patterned by exposure, development, and hardening is being studied. The plastic film base material tends to have a stronger intermolecular bonding force of the photosensitive resist than the glass substrate, and after the development treatment after pre-drying in a thermal drying furnace, the photosensitive resist is It was confirmed that a residue is likely to be generated in the dissolved and removed portion. Therefore, it is necessary to control the amount of thermal polymerization by pre-drying when using a liquid photosensitive resist.

The known literature is described below.
JP 2001-56405 A JP-A-6-273619

  An object of the present invention is to provide a method for producing a flexible color filter that is easily formed on a film substrate without increasing the number of steps and equipment.

  The present invention relates to a method for producing a color filter by a photolithography method on a plastic film substrate, wherein a liquid photosensitive resist is intermittently applied to a pattern forming area by a coater, and is dried by a vacuum drying apparatus capable of processing the pattern forming area. In this way, the hue, chromaticity and film thickness of the color filter are stably controlled.

The invention of claim 1 of the present application is a method for producing a color filter by a photolithography method on a film substrate supplied from a take-up roll,
With a batch type vacuum drying apparatus that has a mechanism that sandwiches the film substrate from the top and bottom with a structure that divides liquid photosensitive resist to the effective area of the color filter of the film substrate by the coater, intermittently coats it, and divides it vertically. A non-effective area of a film substrate is sandwiched between structures, and a photosensitive resist in the effective area is dried with a solvent.

  The invention according to claim 2 of the present application is characterized in that a part of the structure to be divided between the upper and lower parts of the vacuum drying apparatus that is in contact with the film base is smooth on one side and provided with an O-ring on the other side. The method for producing a color filter according to claim 1.

  In the invention according to claim 3 of the present invention, the structure divided into the upper and lower parts of the vacuum drying apparatus is retracted up and down during the film substrate conveyance, and the smooth surface of the structure is the conveyance surface of the film substrate during the vacuum drying. 3. The method for producing a color filter according to claim 2, wherein the film substrate is sandwiched between the structure having the same height and the other O-ring provided, and vacuum processing is performed. is there.

  The invention according to claim 4 of the present application is characterized in that the inner dimension of the O-ring pressing part of the vacuum drying apparatus in the direction of the film substrate conveyance head and tail is longer than the coating length of the photosensitive resist. This is a manufacturing method of the color filter.

  According to the first aspect of the present invention, the liquid photosensitive resist is limited to the effective area of the color filter by the coater and intermittently applied, so that the coating thickness of the photosensitive resist is changed in the flow direction of the plastic film substrate. High-precision control is possible in the width direction.

In addition, the photosensitive resist is prevented from being applied to an ineffective area between the effective area and the effective area, so that the use efficiency of the photosensitive resist is improved and the photosensitive resist in the ineffective area portion is removed. This process can be omitted, and the photosensitive resist coated on the ineffective area can be prevented from coming into contact with the conveying section of the manufacturing apparatus and causing dust generation.
The exposure equipment is premised on intermittent conveyance and processing of plastic film substrates. The feed pitch of the coater, vacuum dryer, and exposure unit is controlled based on the effective area length, and fine adjustment mechanisms such as dancers are provided. By providing it, it becomes possible to control easily, and from the coater unit to the exposure unit can be controlled by the same apparatus.

  By making the structure that divides the vacuum drying device up and down into a batch type consisting of a mechanism that sandwiches the film substrate from above and below, the progress of the thermal polymerization of the photosensitive resist by the solvent drying process in the heat drying furnace can be suppressed, and intermittent It is possible to design and control the process of vacuum drying only the effective area during transportation.

  Moreover, it becomes possible to reduce the deformation | transformation of the ineffective area pinched | interposed into the vacuum dryer by setting it as the process structure which pinches | interposes a plastic film base material up and down.

  Also, by not having a high-temperature thermal drying device between the coating device and the exposure device, heat transfer to the surroundings can be suppressed, and high-precision temperature control such as the exposure device can be facilitated, and the distance between each device can be reduced. And the installation space can be reduced.

  Since the method for producing a color filter of the present invention has the above-described effects, the production of a flexible color filter easily formed on a film substrate without an increase in the number of steps and equipment as compared with the conventional production method. It can be a method.

  According to the second aspect of the present invention, the structure of the O-ring restraining portion of the chamber of the vacuum drying apparatus has a flat surface in contact with the film base of one structure, and a portion in contact with the other structure. By providing the O-ring, it is possible to maintain the vacuum in the chamber and to reduce the deformation of the ineffective area of the film base due to the O-ring pressing of the chamber.

  According to the third aspect of the present invention, when the film base material is transported, the structure is retracted up and down, so that the surface of the base material contacts the chamber of the vacuum drying device when the film base material is transported, and scratches occur. Can be avoided.

  And at the time of vacuum drying treatment, by controlling the height of the transport surface of the film base and the height of the smooth surface of the structure to be the same, an excessive external force pulling the film base is applied, and the film base is It becomes possible to prevent the photosensitive resist coated with the stretched dimensional accuracy from being lowered or the film base material from being stretched to dry and wrinkle the coated film when the external force is released.

According to the fourth aspect of the present invention, by designing the inner dimension in the flow direction of the film substrate in the chamber of the vacuum drying apparatus to be longer than the effective resist coating length, the plastic film The base material is pressed by the O-ring of the chamber outer frame of the vacuum drying device in a non-effective area, and solvent drying becomes possible. By controlling the coating length of the photosensitive resist, it is possible to prevent the photosensitive resist from coming into contact with the O-ring and deteriorating the O-ring, and to prevent dust from adhering to the O-ring and drying.

  According to the configuration of the present invention, it becomes possible to transfer a liquid photosensitive resist usually used in a photolithographic method of a glass substrate as it is onto a flexible base material such as a long plastic film. It is possible to provide a flexible flat display with high reproducibility.

  The best mode for carrying out these will be specifically described below.

As a coater that applies liquid photosensitive resist to the effective area of the color filter with a coater and can apply intermittently, coating equipment such as die coater, slit coater, wire bar coater, roll coater, ink jet, and resin letterpress can be used. is there.
As the transport control of the film base material and the coating part for intermittent coating, a control method for transporting the film base material for the coating length to the fixed coating device, and the coating device for the fixed film base material It is possible to use a control method for moving the film by the coating length.

  In order to control the coating thickness of the photosensitive resist in the flow direction and width direction of the film substrate, it is important to control the distance between the film substrate and the coating device. It can be held by a back roller. In the case of a flat plate, a method of holding the film substrate by vacuum or static electricity is possible. In the case of a back roller, the film substrate can be wound around and held by a tensioned back roller.

  Any method is possible, but in controlling intermittent conveyance, a control method in which the coating apparatus is moved by the coating length with respect to the film substrate fixed to the flat plate is desirable.

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.

  FIG. 1 is an explanatory view schematically showing a positional relationship between an effective area of a color filter and a film base according to an embodiment of the present invention, a coater, a structure that is vertically divided, and FIG. FIG. 1B is an explanatory diagram showing the positional relationship between the film substrate, the coater, and the structure, and FIG. 1B is an explanatory diagram showing the positional relationship between the film substrate and the effective area of the color filter. The film base 101 is coated with a photosensitive resist by a coater 102 on a coating surface plate 103. After coating, the film substrate 101 is taken up by the take-up unit 113 and moved intermittently at the feed pitch 112. Further, the ineffective area 111 of the film substrate 101 is sandwiched between the smooth surface side structure 104 and the O ring side structure 105 provided with the O ring 106. When exposure is performed using an exposure apparatus, a photomask 107 is placed on the coated photosensitive resist, and an exposure area 109 on the photomask is exposed. At this time, the area 108 of the photomask pattern is exposed as an effective area 110 on the photosensitive resist. A non-effective area 111 is between the effective area 110 and an adjacent effective area.

  FIG. 2 is an explanatory view schematically showing an example of the structure according to the present embodiment. The structure is configured such that the film base 101 is sandwiched between the smooth surface side structure 104 and the O-ring side structure 105 provided with the O-ring 106 by the ineffective area 111 of the film base 101. 2A, the smooth surface side structure 104 is provided on the lower side of the film substrate 101, and the O-ring side structure 105 is provided on the upper side. FIG. In FIG. 2B, the smooth surface side structure 104 is provided on the lower side of the film base 101, and the O ring side structure 105 is provided on the upper side. It is explanatory drawing which shows the structure which provided the resin plate 114 on the surface. In addition to this, a structure in which shutter-like doors are provided before and after the cylindrical chamber is conceivable, but the deformation of the ineffective area 111 of the film base 101 at the portion in contact with the film base 101 is reduced, and the film In order to facilitate the conveyance control, a mechanism in which the former structure divided into upper and lower parts sandwiches the film substrate 101 from above and below is desirable.

  It is desirable to design the inner dimension in the flow direction of the film substrate 101 in the chamber of the vacuum drying apparatus longer than the photosensitive resist coating length as shown in FIG. Unlike the single-wafer substrate, since the film substrate 101 is continuously fed, the area 108 of the image pattern including the peripheral mark exposed by the exposure apparatus is used as the effective area 110 of the present invention, and the color filter is manufactured. When the necessary areas before and after the effective area 110 are the non-effective areas 111, the layout is such that the effective areas 110 and the non-effective areas 111 are alternately arranged.

When designing and controlling a photolithographic apparatus, the chamber length of the vacuum drying apparatus is required to be longer than the effective area 110 length and within the dimension between the non-effective areas 111.
The feed pitch 112 when supplying the film substrate 101 to the photosensitive resist coating apparatus on the film substrate 101 is equal to or larger than the inner dimension of the O-ring 106 pressing portion of the chamber of the vacuum drying apparatus. It is desirable to control it.

  The coating length of the intermittent application of the photosensitive resist only needs to be shorter than the chamber length of the vacuum drying device, and the length relative to the effective area 110 may be any as long as the portion corresponding to the image pattern area 108 is coated.

The structure of the O-ring 106 restraining part of the chamber of the vacuum drying apparatus is such that the surface of the structure on one side that contacts the film base is flat as shown in FIG. It is desirable. In a structure in which O-rings are provided on both sides, an external force such as expansion / contraction or twist due to deformation of the O-ring at the contact portion is applied to the film substrate, which is not desirable.
The material of the O-ring is not particularly specified as long as it has elasticity such as silicone rubber, urethane rubber, butane rubber.

  The smooth surface that comes into contact with the film base material may be a smoothed surface of a metal such as SUS or aluminum that is the same as the chamber structure, and the end is rounded to prevent scratches on the base material. Alternatively, a structure in which a resin plate such as a Teflon (registered trademark) material is bonded can be used.

  The portion of the structure of the present invention that does not come into contact with the film substrate comes into contact with the film substrate due to its own weight, and the concave surface retracted from the flat surface or the surface of the O-ring so that back surface scratches do not occur due to dragging. It is desirable to process into a shape.

  The upper and lower structures of the vacuum drying apparatus are composed of a smooth surface side structure 104 and an O-ring side structure 105 provided with an O-ring 106. When the film substrate 101 is transported, the upper and lower structures are retracted up and down. It is desirable to avoid the surface from coming into contact with the upper and lower structures and scratching the film substrate 101 and the pattern thereon. FIG. 3 is an explanatory view schematically showing an example of the relationship between the flexure of the film substrate and the structure according to the present embodiment. The retraction amount may be larger than the slack amount 115 due to the weight of the film substrate 101 as shown in FIG. The amount of slack 115 varies depending on the size of the O-ring pressing portion of the structure and the tension applied to the film base, but it occurs on the order of several millimeters. Therefore, the retracted amount on one side of the upper and lower structures is preferably more than that. .

  In the vacuum drying process, it is desirable to control the film substrate so that the conveyance height is the same as the height of the smoothed surface of the structure.

  The film base material is held by transport rollers before and after the vacuum drying apparatus, and the film base material is loosened by several millimeters due to its own weight.

  Therefore, deformation of the film substrate can be avoided by controlling the height below the amount of slackness of the film substrate at the position in contact with the smoothed surface of the structure.

  When vacuum drying is performed at a height that is more than the amount of loosening, an external force that stretches the film substrate by several millimeters will be applied, resulting in at least a few micron deformation of the film substrate and an increase in the dimension of the formed pattern. For this reason, it becomes difficult to superimpose patterns with a positional accuracy of several microns.

  When a thick film base material is sandwiched between flat surfaces, gaps due to thickness occur on the left and right sides of the film base material. This gap can be closed by the collapse amount of the O-ring by being sandwiched through an elastic O-ring. Although there is a limit due to the thickness of the film base and the elasticity of the O-ring, the thickness of the film base that can be supplied from the roll and can stably obtain the degree of vacuum by the collapse amount of the O-ring is 200 μm or less, preferably 100 μm The following is preferred.

  Although the degree of vacuum can be obtained even with a substrate having a thickness of more than 200 μm, deformation and deterioration of the portion of the O-ring where the edge of the film substrate hits is likely to progress due to repeated use, and stability control becomes difficult.

  Since the film base material is made of a heat-resistant and smooth organic resin film, a pattern can be formed in a photolithography process by film conveyance, and a thermosetting treatment after the pattern formation is possible. The film base is not limited to a single composition such as PET, PEN, OPS, PC, etc. If heat resistance and smoothness can be obtained, a laminated film of these film materials can be used, and SiOx is formed on the surface of the film base. A coating layer made of an organic resin different from the gas barrier film or the film substrate may be formed.

  In order to increase the positional accuracy of overlaying a pattern such as Red, Green, Blue, etc. on the film substrate with reference to the black pattern, it is important to control the deformation amount of the film substrate and the temperature control. It is desirable to use a material having a low thermal expansion coefficient of the film base.

The thermal expansion coefficient of the film base material developed for the current liquid crystal display device is about 20 * 10 ⁻⁶ cm / cm / ° C. When the temperature changes by 1 ° C. with a screen size of 250 mm, the length of the 5 micron base material increases. Change. In order to ensure the display quality of liquid crystal display devices, the difference in total pitch between black pattern and red, green, blue, etc. pattern must be controlled within ± 1.5 microns. The difference in coefficient of thermal expansion is preferably 6 * 10 ⁻⁶ cm / cm / ° C. or less. The film substrate can be applied as long as it is not flexible, such as a plastic plate, but can be selected according to the drying temperature after pattern formation. Polyethersulfone, cycloolefin polymer A film made of polyimide, polycarbonate, polymethyl methacrylate, triacetyl cellulose, or the like can be used. Of these, heat-resistant polyether sulfone, cycloolefin polymer, polyimide and the like are preferable. Moreover, the base material which consists of material which added the inorganic filler to the said resin and improved heat resistance may be sufficient. The film substrate may be stretched or unstretched.

  As the photosensitive resist, a general liquid resist composed of an organic resin, a monomer, a pigment, a surfactant, and an organic solvent can be used.

The organic resin of the present invention is a clear resin of thermosetting resin or photocurable resin, and preferably contains at least one resin having an aromatic ring structure in its molecular structure. Examples of the resin having an aromatic ring structure in the molecular structure include polyester resins, acrylic resins, epoxy resins, melamine resins, and benzoguanamine resins.

  Examples of such resins include polyester, polystyrene, phenol resin, xylene resin, epoxy resin, polycarbonate, aromatic nylon resin, or a copolymer containing styrene, aromatic acid, phenol, etc., acrylic resin, melamine resin, benzoguanamine resin. Can be raised.

  Especially, what combined any one or more of a polyester resin, an acrylic resin, or an epoxy resin, and any one or more of a melamine resin or a benzoguanamine resin is preferable. Furthermore, a combination of a polyester resin and a melamine resin and a combination of an epoxy resin, a melamine resin, and a benzoguanamine resin are more preferable.

  As this resin, a general thermosetting resin used for manufacturing a color filter can be used, but a radical type ultraviolet curable resin, a cationic type ultraviolet curable resin, and an electron beam curable resin may be used.

A color filter was formed on a plastic film substrate by a photolithographic method using a liquid photosensitive resist composed of black, red, green, and blue.
As the film substrate, a light-transmissive PET substrate having a film thickness of 120 μm was prepared in a roll shape of 300 mm width and 20 m.

The apparatus structure used the apparatus which consists of unwinding of a film base material, a die coater, a vacuum drying apparatus, an exposure apparatus, and winding, the inorganic alkali spray developing apparatus which has unwinding and winding separately, and the thermosetting apparatus. All apparatuses were transported with the film surface facing up.
○ The exposure apparatus set the area of the image pattern including the peripheral marks to 250 mm □. The exposure area of the head and tail non-exposure areas in the transport direction was controlled by a shading plate.

A pattern with a black line width of 20 μm and a pixel pitch of 70 μm was used as the color filter pattern.
○ The die coater fixed the film base on a vacuum suction surface plate with a porous structure, and moved the die coater from the upper side for coating. No photosensitive resist is applied to the left and right 20mm in the transport direction, the head and tail 260mm in the transport direction are set to the effective area, the feed pitch for intermittent transport is set to 350mm, and the ineffective area between the effective area and the effective area is set to 90mm. did.
○ The vacuum drying oven was designed with a 350mm dimension between the head and tail O-rings in the transport direction. A structure having a smoothed surface was provided on the lower side, and a structure having an O-ring was provided on the upper side. 1 for O-ring
0 mmφ silicone rubber was used. The lower structure has a concave shape with the non-contact portion retracted 10 mm.

The color filter was processed using the photolithography apparatus.
1) First, a film substrate was fed at a pitch of 350 mm onto a coating platen, and a photosensitive resist was coated with a coating length of 260 mm by a die coater having an opening width of 260 mm.
2) Next, the film base material coated with the photosensitive resist is sent to a vacuum drying device at a pitch of 350 mm, and is sandwiched between the smoothed surface and the O-ring at the 90 mm wide portion of the ineffective area, and vacuum dried at an ultimate vacuum of 300 Pa. went.
3) The vacuum-dried film substrate is fed to the exposure apparatus at a pitch of 350 mm, exposed to light using a 350 mm square photomask having an image pattern area including peripheral marks, and then a 30 μmt protective film is sandwiched between them. I wound up with.
4) The exposed film substrate was developed by a developing device containing an inorganic alkali as a main component, and was wound with a 30 μmt protective film interposed therebetween.
5) The film substrate subjected to the development treatment was subjected to a curing treatment in a thermosetting furnace.
6) Steps 1) to 5) were repeated 4 times to obtain a color filter.

  By using this manufacturing method, it is possible to easily adjust the color and film thickness of the photosensitive resist, and the overlay accuracy of each color is controlled within ± 5 μm without causing scratches on the back surface of the film substrate. Thus, a film-like color filter with high display quality was obtained.

A color filter was formed on a plastic film substrate by a photolithographic method using a liquid photosensitive resist composed of black, red, green, and blue.
The film base material was prepared in the form of a roll having a width of 300 mm and a thickness of 20 m by forming a 1000 mm gas barrier film SiOx on a light-transmitting PET base material having a film thickness of 100 μm.

The apparatus configuration includes film substrate unwinding, die coater, vacuum drying apparatus, low temperature hot plate, exposure apparatus, winding apparatus, inorganic alkali spray developing apparatus having unwinding and winding individually, and thermosetting apparatus. Was used. All apparatuses were transported with the film surface facing up.
○ The exposure apparatus set the area of the image pattern including the peripheral marks to 280 mm □.

As a color filter pattern, a pattern having a black line width of 10 μm and a pixel pitch of 55 μm was used.
○ The die coater fixed the film base on a vacuum suction surface plate with a porous structure, and moved the die coater from the upper side for coating. No photosensitive resist is applied to the left and right 10mm in the transport direction, the head and tail 280mm in the transport direction are set to the effective area, the feed pitch for intermittent transport is set to 350mm, and the ineffective area between the effective area and the effective area is set to 70mm. did.
○ The vacuum drying oven was designed with a 350mm dimension between the head and tail O-rings in the transport direction. A structure having a smoothed surface was provided on the lower side, and a structure having an O-ring was provided on the upper side. 1 for O-ring
0 mmφ silicone rubber was used. The lower structure has a concave shape with the non-contact portion retracted 10 mm.
○ The low-temperature hot plate was formed with an inorganic film on the surface of the film substrate and the black pattern was aligned. Therefore, thermal polymerization was lightly applied to the photosensitive resist at 70 ° C to improve adhesion. The feed pitch is 350 mm and the repair area is 300 mm □.

The color filter was processed using the photolithography apparatus.
1) First, a film base material was fed at a pitch of 350 mm onto a coating platen, and a photosensitive resist was coated at a coating length of 280 mm by a die coater having an opening width of 280 mm.
2) The substrate was heat-treated at 70 ° C. for 1 min using a low temperature hot plate.
3) The substrate was sent to a vacuum drying apparatus at a pitch of 350 mm, sandwiched between a smoothed surface and an O-ring at a 70 mm wide portion in an ineffective area, and vacuum dried at a final vacuum of 250 Pa.
4) The vacuum-dried film base material is sent to an exposure apparatus at a pitch of 350 mm, exposed to light using a 350 mm square photomask having an image pattern area including peripheral marks, and then a 30 μmt protective film is sandwiched between them. I wound up with.
5) The exposed film substrate was developed by a developing device containing an inorganic alkali as a main component, and wound up with a 30 μmt protective film interposed therebetween.
6) The film substrate subjected to the development treatment was cured in a thermosetting furnace.
7) Except 2), 1) to 6) were repeated 3 times to obtain a color filter.
By using this manufacturing method, it is possible to easily adjust the color and film thickness of the photosensitive resist, and the overlay accuracy of each color is controlled at ± 4 μm without causing scratches on the back surface of the film substrate. Thus, a film-like color filter with high display quality was obtained.

  This example is an example for comparison.

A color filter was formed on a plastic film substrate by a photolithographic method using a liquid photosensitive resist composed of black, red, green, and blue.
As a film base material, a light-transmissive PEN base material having a film thickness of 100 μm was prepared in a roll shape of 300 mm width and 20 m.

The apparatus configuration used was a coating apparatus, an exposure apparatus, an unwinding inorganic alkali spray developing apparatus, and a thermosetting apparatus in which a thermal drying furnace was provided immediately after the die coater having individual unwinding and winding. All apparatuses were transported with the film surface facing up.
○ The coating apparatus carried out unwinding, coating, heat drying, and winding by continuous conveyance.
○ The exposure apparatus set the area of the image pattern including the peripheral marks to 260 mm □.

As a color filter pattern, a black line width of 20 μm and a pixel pitch of 70 μm were used.

The color filter was processed using the photolithography apparatus.
1) A liquid photosensitive resist is coated on a film substrate by a die coater, and is passed through a heat drying oven with a substrate temperature of 100 ° C. for 1 to 2 minutes, and then a 30 μmt protective film is sandwiched between the films. I wound up with.
2) The film substrate was fed into an exposure apparatus at a pitch of 350 mm, and after performing an exposure process using a 350 mm □ photomask having an image pattern area including peripheral marks, the film substrate was wound.
3) The exposed film base material was developed by a developing apparatus containing an inorganic alkali as a main component, and wound up with a 30 μmt protective film in between.
4) The film substrate subjected to the development treatment was cured in a thermosetting furnace.
5) Steps 1) to 4) were repeated 3 times to obtain a color filter.
In this production method, since the liquid photosensitive resist was dried by heat, the thermosetting proceeded and the adhesion with the film substrate was increased, resulting in a phenomenon that a residue remained after development. The degree of this tendency varies depending on the color of the photosensitive resist, and the heat drying condition was finely adjusted between 1 and 2 minutes to reduce it, but it was not resolved.

  Also, continuous coating is required for the coating device, intermittent conveyance is required for the exposure device, and continuous conveyance is required for the development / baking device, and it is necessary to assemble the coating device and the exposure device as separate devices in order to control the conveyance of the film substrate. There is a problem that the installation space of the apparatus increases.

It is explanatory drawing which showed typically the positional relationship of the effective area of the film base material and the coater which concern on embodiment of this invention, the structure divided | segmented up and down, and a color filter. It is explanatory drawing which showed typically the example of the structure which concerns on this Embodiment. It is explanatory drawing which illustrated typically the relationship between the bending of the film base material which concerns on this Embodiment, and a structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Film base material 102 ... Coater 103 ... Coating surface plate 104 ... Smooth surface side structure 105 ... O-ring side structure 106 ... O-ring 107 ... Photomask 108 ... Pattern area 109 ... Exposure area 110 ... Effective area 111 ... Non-effective area 112 ... Feed pitch 113 ... Winding part 114 ... Resin plate 115 ... Looseness

Claims (4)

In a method for producing a color filter by a photolithography method on a film substrate supplied from a winding roll,
With a batch type vacuum drying apparatus that has a mechanism that sandwiches the film substrate from the top and bottom with a structure that divides liquid photosensitive resist to the effective area of the color filter of the film substrate by the coater, intermittently coats it, and divides it vertically. A method for producing a color filter, wherein a non-effective area of a film substrate is sandwiched between structures and solvent drying of a photosensitive resist in the effective area is performed.   2. The color filter according to claim 1, wherein the portion of the structure to be divided between the upper and lower parts of the vacuum drying apparatus that is in contact with the film base is smooth on one side and provided with an O-ring on the other side. Production method.   The structure to be divided into the upper and lower parts of the vacuum drying device is retracted up and down during the film substrate conveyance, and during the vacuum drying, the smooth surface of the structure rises to the same height as the film substrate conveyance surface. The method for producing a color filter according to claim 2, wherein the film base material is sandwiched between the O-ring and the structure, and vacuum processing is performed.   The method for producing a color filter according to claim 2 or 3, wherein an inner dimension of the O-ring pressing portion of the vacuum drying device in the direction of the film substrate conveyance head and tail is longer than the coating length of the photosensitive resist.