JP2012168387A - Scraping jig, contrast improvement sheet manufacturing device equipped therewith, and contrast improvement sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scraping jig capable of reducing a defect, and a contrast improvement sheet manufacturing device equipped therewith.SOLUTION: A scraping jig is used to manufacture a contrast improvement sheet that comprises a light transmission part 1 and a light absorption part. The scraping jig comprises: a first scraping blade 31 for scraping an ink composition that is supplied from a surface 1a of the light transmission part 1 with a plurality of grooves arranged in parallel on the surface 1a, to the top of the surface 1a; a second scraping blade 32 for further scraping the ink composition remaining on the surface 1a of the light transmission part 1 after scraping by the first scraping blade 31; and a holder 34 for holding the first scraping blade 31 and the second scraping blade 32. The holder 34 holds the first scraping blade 31 and the second scraping blade 32 so that each angle of a tip 31a of the first scraping blade 31 and a tip 32a of the second scraping blade 32 becomes 40° or more and 70° or less with respect to the surface of the light transmission part 1.

Description

  The present invention relates to a scraping jig, a contrast-enhancing sheet manufacturing apparatus including the same, and a contrast-enhancing sheet.

  In a liquid crystal display device, it is usually preferred that the viewing angle is wide so that a good image can be obtained from any position of the observer. On the other hand, for example, when working on a commuter train or in a liquid crystal display device installed in a public place such as an ATM, it may be difficult to see the screen from people around you. There is a demand for a peeping prevention function for protecting privacy so that it can be seen only by an observer of the display device and cannot be seen by others. In car-mounted liquid crystal display devices such as car navigation systems, the screen of the liquid crystal display device is reflected on the window glass at night and the like, and the phenomenon of blocking the field of view occurs. Control of the light emission angle is desired.

  In response to such a demand, for example, Japanese Patent Laid-Open No. 2006-119365 (Patent Document 1) proposes a louver type optical sheet having a structure in which light transmission layers and light shielding layers are alternately arranged. In addition, it is disclosed to use a light shielding layer in which a material constituting the light transmission layer is mixed with a filler such as carbon black or carbon fiber.

  On the other hand, the louver-type optical sheet as described above simply cuts the image light in the oblique direction. Therefore, depending on the type of the display device, the diffusion light source of the image light that should reach the observer is reduced. As a result, the brightness of the display screen may be reduced.

  In order to solve the above problem, it has been proposed to install a contrast enhancing sheet that can improve the contrast by blocking external light and reduce the occurrence of double images. As such a contrast improving sheet, sheets having various structures have been proposed. For example, a light transmitting portion having a plurality of grooves arranged in parallel on the surface, a material having a refractive index lower than that of the light transmitting portion, and a carbon pigment. Have been proposed (for example, Japanese Patent Application Laid-Open No. 2006-85050, etc .: Patent Document 2).

  Then, in the production of the contrast enhancing sheet, an ink composition in which colored resin beads are mixed with a lens material such as an ionizing radiation curable resin is filled in the groove of the light transmitting portion, and is cured by irradiating with ionizing radiation. (For example, International Patent Application Publication No. WO2006 / 090784: Patent Document 3).

  The ink composition is filled by, for example, supplying the ink composition to the surface of the light transmitting portion from the upstream side of the doctor blade while moving the sheet-shaped light transmitting portion having a plurality of grooves arranged on the surface. The ink composition can be formed by scraping the ink composition on the surface of the light transmitting portion with a single doctor blade while forming an ink reservoir upstream of the blade and in the immediate vicinity of the doctor blade.

  However, when the ink composition is filled by such a method, many white streak defects may occur in the light absorbing portion. Also, scraping defects and black streak defects may occur. Since the appearance quality of the contrast enhancing sheet is directly related to the image quality, high quality is required. For this reason, it is preferable to reduce the white streak defect as described above as much as possible.

JP 2006-119365 A JP 2006-85050 A International Application Publication WO2006 / 090784

  The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a scraping jig, a contrast-enhancing sheet manufacturing apparatus, and a contrast-enhancing sheet manufacturing method capable of reducing white streak defects, scraping defects, and black streak defects.

  As a result of intensive research to sufficiently scrape off the ink composition, the present inventors have found that by improving the scraping jig, it is possible to reduce white stripe defects, scraping defects and black stripe defects. I found it. Here, in this specification, the “white streak defect” means that the groove is not filled with the ink composition and the light absorption part is partially recessed. “Poor scraping” means that the ink composition remains on the light transmitting portion after the ink composition is scraped and is not linear or dotted. The “black stripe defect” means that the ink composition remains on the light transmission portion after the ink composition is scraped off, and the ink composition is linear or dotted. The black streak defect is sometimes called “fogging”. The present invention has been completed based on such findings.

  According to one aspect of the present invention, it is used for manufacturing a contrast-enhancement sheet comprising a light transmission part having a plurality of grooves arranged in parallel on the surface and a light absorption part formed in the groove of the light transmission part. A first scraping blade for scraping an ink composition supplied onto the surface from the surface of the light transmitting portion having a plurality of grooves arranged in parallel on the surface; A second scraper, which is disposed at a predetermined interval from the first scraping blade, and further scrapes the ink composition remaining on the surface of the light transmitting portion after scraping by the first scraping blade. And a holder for holding the first scraping blade and the second scraping blade, and the holder includes a tip portion of the first scraping blade with respect to a surface of the light transmitting portion and the holder. The angle of the tip of the second scraping blade is Characterized in that it holds the first scraping blade and the second scraping blade as respectively a 40 ° to 70 ° or less, the scraping jig is provided.

  According to another aspect of the present invention, in a contrast-enhancement sheet manufacturing apparatus comprising: a light transmissive portion having a plurality of grooves arranged in parallel on a surface; and a light absorbing portion formed in the groove of the light transmissive portion. And the manufacturing apparatus of the contrast improvement sheet | seat characterized by providing said scraping jig is provided.

  According to another aspect of the present invention, there is provided a method for manufacturing a contrast enhancing sheet, comprising: a light transmission part having a plurality of grooves arranged in parallel on a surface; and a light absorption part formed in the groove of the light transmission part. The ink composition is continuously supplied to the surface of the light transmission part while moving the sheet-like light transmission part in which a plurality of grooves are arranged in parallel on the surface, from the supply position of the ink composition The ink composition on the surface of the light transmitting portion while forming an ink reservoir containing an ink composition on the upstream side of the first scraping blade disposed on the downstream side and in the immediate vicinity of the first scraping blade Scraping an object with the first scraping blade and the second scraping blade disposed at a predetermined distance from the first scraping blade on the downstream side of the first scraping blade. The scraping of the ink composition comprises The first scraping blade and the first scraping blade and the second scraping blade have an angle of 40 ° to 70 ° with respect to the surface of the transmission portion. A method for producing a contrast-enhancing sheet is provided, which is performed in a state where two scraping blades are arranged.

  According to the scraping jig of one aspect of the present invention, the contrast-enhancing sheet manufacturing apparatus according to another aspect of the present invention, and the contrast-enhancing sheet manufacturing method according to another aspect of the present invention, white streak defects, scraping defects In addition, black streaks can be reduced.

It is the figure which showed typically a part of manufacturing apparatus of the contrast improvement sheet | seat which concerns on embodiment. It is sectional drawing of the scraping jig which concerns on embodiment. It is a side view of the scraping jig concerning an embodiment. It is the figure which showed typically the manufacturing process of the contrast improvement sheet | seat which concerns on embodiment. It is the figure which showed typically the formation process of the light transmissive part which concerns on embodiment. It is the figure which showed the base material which has the adhesion layer and peeling layer which concern on embodiment. It is the figure which showed typically the mode of scraping of the ink composition by the scraping jig which concerns on embodiment. It is sectional drawing of the display apparatus provided with the contrast improvement sheet | seat which concerns on embodiment.

<Scraping jig and contrast improving sheet manufacturing apparatus>
First, a scraping jig and a contrast improving sheet manufacturing apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram schematically showing a part of a contrast-enhancing sheet manufacturing apparatus according to the present embodiment, FIG. 2 is a cross-sectional view of a scraping jig according to the present embodiment, and FIG. It is a side view of the scraping jig which concerns on a form. In addition, the arrow A in FIG. 1 represents the moving direction of a light transmission part, and the arrow B represents the circulation direction of an ink composition.

  The contrast-enhancement sheet manufacturing apparatus includes a filling apparatus 10 shown in FIG. The filling device 10 is for filling the ink composition 2 into the groove 1b of the light transmitting portion 1 in which the groove 1b is arranged in parallel on the surface 1a, and mainly includes a supply unit 20, a scraping jig 30, and the like. And an ink circulation system 40 and a transport system (not shown).

  The supply unit 20 is for supplying the ink composition 2 to the surface 1 a of the light transmission unit 1. It is preferable that the supply part 20 can supply the ink composition 2 uniformly in the width direction of the light transmission part 1.

  Examples of the supply unit 20 include a die coater, a bar coater, a roll coater, and a knife coater. Among these, the ink composition 2 is uniformly applied to the surface 1 a of the light transmission unit 1 in the width direction of the light transmission unit 1. A die coater that can be supplied is preferred.

  The scraping jig 30 is disposed downstream of the supply position of the ink composition 2 by the supply unit 20. As shown in FIGS. 1 to 3, the scraping jig 30 includes a first scraping blade 31 and a first scraping blade that scrape the ink composition 2 supplied onto the surface 1 a of the light transmitting portion 1. A second scraping blade 32 for further scraping off the ink composition 2 remaining on the surface 1a of the light transmitting portion 1 after scraping by the light transmitting portion 1, a contact plate 33 attached to the second scraping blade 32, and a first scraping A holder 34 for holding the blade 31 and the second scraping blade 32 is provided. The contact plate 33 may not be provided.

  As shown in FIG. 2, the second scraping blade 32 is disposed downstream of the first scraping blade 31 with respect to the moving direction of the light transmission unit 1. Further, the first scraping blade 31 and the second scraping blade 32 are arranged so as to be orthogonal to the extending direction of the groove 1b.

  The first scraping blade 31 and the second scraping blade 32 are thin plate-like, and the thickness of the first scraping blade 31 and the second scraping blade 32 can be about 200 μm. . As the first scraping blade 31 and the second scraping blade 32, for example, a doctor blade or the like can be used.

  As shown in FIG. 2, the first scraping blade 31 and the second scraping blade 32 are configured such that the front end portion 31 a of the first scraping blade 31 and the second scraping blade with respect to the surface 1 a of the light transmitting portion 1. 32 are held by the holder 34 so that the angles α and β of the tip 32a are 40 ° to 70 °, preferably 50 ° to 65 °. The reason why the angles α and β are set in this range is that when the angles α and β are less than 40 °, the ink composition 2 is not sufficiently scraped off, and there is a risk that scraping failure may occur. When the angles α and β exceed 70 °, although the scraping efficiency by the first scraping blade 31 and the second scraping blade 32 is improved, the first scraping blade 31 in contact with the ink composition 2 and This is because the area of the second scraping blade 32 is small, and black stripe defects may occur.

  As shown in FIG. 2, the first scraping blade 31 is arranged so that the tip 31 b of the first scraping blade 31 is in contact with the surface 1 a of the light transmitting portion 1, and the second scraping blade 31 The blade 32 is preferably arranged so that the tip 32 b of the second scraping blade 32 is separated from the surface 1 a of the light transmission part 1.

The tip 32 b of the second scraping blade 32 protrudes from 0.25 mm to 0.55 mm with respect to the tip 31 b of the first scraping blade 31. Here, the fact that the tip 32b of the second scraping blade 32 protrudes from 0.25 mm to 0.55 mm below the tip 31b of the first scraping blade 31 means that the protrusion length L shown in FIG. It means that ₁ is 0.25 mm or more and 0.55 mm or less.

  The distance d between the first scraping blade 31 and the second scraping blade 32 shown in FIG. 2 is preferably 0.05 to 2 mm. This numerical range is preferable because when the distance d is less than 0.05 mm, the first scraping blade 31 and the second scraping blade 32 overlap, and the ink composition 2 is scraped off. May be insufficient. If the distance d exceeds 2 mm, the ink composition 2 is clogged between the first scraping blade 31 and the second scraping blade 32, which may cause pitch streaks.

  The contact plate 33 shown in FIG. 2 is attached to a surface 32d of the second scraping blade 32 opposite to the surface 32c on the first scraping blade side. Although the material which comprises this board 33 is not specifically limited, For example, stainless steel etc. can be used. The thickness of the plate 33 is preferably 150 to 1000 μm. This numerical range is preferable because if the thickness of the contact plate 33 is less than 150 μm, the rigidity of the contact plate 33 is insufficient and black streaks are likely to occur. If the thickness exceeds 1000 μm, the rigidity of the contact plate 33 becomes more than necessary, and the bending of the second scraping blade 32 cannot be used, and the filling rate of the ink composition 2 may be reduced. It is.

The contact plate 33 has a vertical length of a portion of the second scraping blade 32 that is not covered by the contact plate 33, that is, the lower end 33a of the contact plate 33 shown in FIG. It is preferable that the length L2 up to the tip 32b is 1 to 10 mm, and more preferably ₃ to 7 mm. This numerical range is a preferable, since the length L ₂ is less than 1 mm, it becomes impossible to use the Nari second scraping blade 32 Works by enhancing the rigidity by contact plate 33, the ink composition is because the second filling rate may be lowered, also the length L ₂ is more than 10 mm, since the rigidity of the contact plate 33 is likely to black streaks become insufficient is likely to occur.

  As shown in FIGS. 1 and 2, the holder 34 is provided at both the holding portion 35 that holds the first scraping blade 31 and the like and both ends 35 a in the width direction of the holding portion 35. And a weir portion 36 that protrudes to the scraping side of the ink composition 2 from the end portion 35a, that is, the upstream side. The dam portion 36 is for holding an ink reservoir 2a described later. By providing the weir portion 36, the ink reservoir 2a can be efficiently held.

  The weir part 36 has a suction hole 36a for sucking a part of the ink composition 2 constituting the ink reservoir 2a. The diameter of the suction hole 36a is preferably 10 to 16 mm. The reason why this numerical range is preferable is that if the diameter is less than 10 mm, it takes a long time to suck the ink composition 2. If the diameter exceeds 16 mm, the ink composition is excessively excessive. This is because the object 2 is sucked.

  The suction hole 36a is formed on either the bottom surface 36b or the side surface of the dam portion 36, but is preferably formed on the bottom surface 36b of the dam portion 36 in consideration of the liquid level stability of the ink reservoir 2a. In FIG. 3, the suction hole 36a is formed from the bottom surface 36b of the dam portion 36 to the outer side surface 36c of the dam portion 36, and the ink composition 2 sucked from the bottom surface 36b side is discharged from the suction hole 36a of the outer side surface 36c. It has come to be. Further, as shown in FIG. 3, when the suction hole 36 a is formed in the bottom surface 36 b of the dam portion 36, the dam portion 36 can suck the ink composition 2 so that the bottom surface 36 b of the dam portion 36 can be sucked. It is preferable to dispose a slight gap between the light transmitting portion 1 and the surface 1a of the light transmitting portion 1.

  An ink circulation system 40 shown in FIG. 1 is connected to the suction hole 36a of the outer side surface 36c. The ink circulation system 40 includes a cleaner 41 such as an air suction cleaner, pumps 42 and 43 such as a diaphragm pump, a mixing tank 44, an unused ink composition storage tank 45, a filter 46, and the like.

  The cleaner 41 is for sucking the ink composition 2 and is disposed in front of the pump 42. The pump 42 is for conveying the ink composition 2 in the cleaner 41 and sending it to the mixing tank 44. The mixing tank 44 is for mixing the collected used ink composition and the unused ink composition 2 b stored in the unused ink composition storage tank 45.

  In the mixing tank 44, the used ink composition and the unused ink composition 2b are preferably mixed so that the mixing ratio is 1: 4 to 4: 1. In the mixing tank 44, the viscosity of the ink composition 2 is adjusted so that the viscosity of the ink composition 2 after mixing is preferably 2500 to 5000 mPa · s, more preferably 3000 to 4000 mPa · s. Is done. This numerical range is preferred because if the viscosity of the ink composition 2 is less than 2500 mPa · s, it may be difficult to fill the groove with the ink composition 2, and the viscosity of the ink composition 2 If it exceeds 5000 mPa · s, it may be difficult to suck the ink composition 2.

  The pump 43 is for sending the mixed ink composition 2 in the mixing tank 44 to the supply unit 20, and the filter 46 is interposed between the pump 43 and the supply unit 20. A conveyance system is for conveying the light transmission part 1, and is comprised from the conveyance roll etc., for example.

  Next, the light transmission part 1 and the ink composition 2 will be described. The light transmission portion 1 shown in FIG. 1 is formed on a base material 3. The groove 1b shown in FIG. 1 has a substantially trapezoidal shape that tapers toward the substrate 3 side. The groove 1b is not limited to a substantially trapezoidal shape, and may be formed in, for example, a substantially V shape or a substantially rectangular shape. The groove 1 b extends along the longitudinal direction of the light transmission part 1.

  The base material 3 is a layer serving as a base for forming the light transmission part 1 and the light absorption part 4 described later. As the base material 3, a transparent resin film, a transparent resin plate, a transparent resin sheet, or transparent glass can be used. Transparent resin films include triacetate cellulose (TAC) film, polyester film such as polyethylene terephthalate (PET), diacetyl cellulose film, acetate butyrate cellulose film, polyethersulfone film, polyacrylic resin film, polyurethane resin film Polyester film, polycarbonate film, polysulfone film, polyether film, polymethylpentene film, polyether ketone film, (meth) acrylonitrile film, etc. can be suitably used. Among these, polyester films are preferably used. . Examples of the polyester film include polyethylene terephthalate, polybutylene terephthalate, polynaphthalene terephthalate, and polytrimethylene terephthalate.

  The ink composition 2 includes a transparent ionizing radiation resin composition and light absorbing particles. As the ionizing radiation curable resin composition, an ionizing radiation curable resin composition used for a conventionally known visibility improving sheet or viewing angle improving sheet can be used. For example, those having an acrylate functional group can be suitably used. Specifically, polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetals having a relatively low molecular weight can be used. Examples thereof include oligomers or prepolymers such as (meth) allylates of polyfunctional compounds such as resins, polybutadiene resins, polythiol polyene resins, and polyhydric alcohols. Although depending on the material constituting the light transmitting portion of the visibility improving sheet, a resin having a refractive index smaller than that of the material constituting the light transmitting portion may be selected from these resins.

  In addition, a reactive diluent may be added to the resin composition. Examples of such a reactive diluent include ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N- Monofunctional monomers such as vinyl pyrrolidone and polyfunctional monomers may be used. Specifically, dimethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di ( Examples include meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and the like.

  In order to convert the ionizing radiation curable resin composition into an ultraviolet curable resin composition, acetophenones, benzophenones, Michler benzoyl benzoate, α-amyloxime ester, tetramethylchuram mono as a photopolymerization initiator in the composition. A mixture of sulfides, thioxanthones, n-butylamine, triethylamine, poly-n-butylphosphine, or the like as a photosensitizer can be used. In particular, in the present invention, it is preferable to mix urethane acrylate as an oligomer and dipentaerythritol hexa (meth) acrylate as a monomer.

  As the light absorbing particles, resin beads or glass beads may be light absorbing particles that can selectively absorb a specific wavelength according to the characteristics of the image light. Carbon black, graphite, fibrous carbon, black oxidation What knead | mixed colorants, such as metal salts, such as iron, dye, and a pigment, can be used. From the viewpoint of easy kneading of the colorant, it is preferable to use resin beads. As the resin beads, melamine beads, acrylic beads, acrylic-styrene beads, polycarbonate beads, polyethylene beads, polystyrene beads, polyvinyl chloride beads and the like can be suitably used. Further, urethane cross-linked fine particles and silicon-based beads can also be suitably used. These resin beads are preferably those having a refractive index difference of about 0.1 of the ionizing radiation curable resin composition described above. Also, as the resin before kneading the colorant, a transparent resin can be used, but a resin colored with a pigment or dye is preferably used, and a specific wavelength is selectively selected according to the characteristics of the image light. Although it may absorb, resin beads colored in black are preferably used.

  Among the above-mentioned materials, carbon black can be preferably used as the colorant. The amount of carbon black kneaded into the resin beads is about 0.1 to 0.7 parts by mass, preferably 0.15 to 0.5 parts by mass, more preferably 1 part by mass of the resin beads. Is 0.2 to 0.35 parts by mass. When the amount of kneading of carbon black is more than 0.7 parts by mass, the resin beads may be easily broken. On the other hand, when the amount is less than 0.1 parts by mass, light absorbing particles having desired blackness can be obtained. There may not be. Carbon black having an average particle diameter of 10 to 500 nm can be suitably used. For example, furnace black, acetylene black, channel black, thermal black, carbon nanotube, carbon fiber and the like can be used. Commercially available products can also be used. For example, HCF series, MCF series, RCF series, LFF series (all manufactured by Mitsubishi Chemical Corporation), Vulcan series (made by Cabot Corporation), Ketjen series (Lion Corporation) Can be suitably used. Here, the average particle diameter means an arithmetic average diameter obtained by observing carbon black particles with an electron microscope.

  In order to improve the dispersibility of the light absorbing particles in the ionizing radiation curable resin composition, the light absorbing particles may be surface-treated. Examples of the surface treatment include hydrophilic treatment with a conventionally known silica coating and surface modification with plasma or the like.

  The ink composition 2 containing each component described above is prepared by mixing a predetermined amount of light-absorbing particles into an ionizing radiation curable resin composition and adding a polymerization initiator or the like as desired. The addition amount of the light absorbing particles is preferably in the range of 15 to 35% with respect to the total mass of the ink composition. By setting this range, it is possible to realize a contrast-enhancement sheet with more excellent contrast. If the light-absorbing particle content is too small, the light-shielding property of the light-absorbing part may be insufficient. If the light-absorbing particle content is too large, the resin beads may come into contact with each other, causing problems such as cracking and chipping. It tends to occur.

<Method for producing contrast improving sheet>
Next, a method for manufacturing a contrast enhancing sheet using the scraping jig 30 according to the present invention will be described with reference to the drawings. FIG. 4 is a diagram schematically showing the manufacturing process of the contrast enhancing sheet according to the present embodiment, and FIG. 5 is a diagram schematically showing the process of forming the light transmission portion according to the present embodiment. FIG. 7 is a diagram showing a base material having an adhesive layer and a release layer according to the present embodiment, and FIG. 7 is a diagram schematically showing how the ink composition is scraped by the scraping jig according to the present embodiment. It is.

  First, the light transmission part 1 in which the plurality of grooves 1b are arranged in parallel in the cross section in the layer thickness direction is formed on the base material 3 (FIG. 4A).

  The formation of the light transmitting portion 1 varies depending on the type of resin used. For example, when the light transmitting portion 1 is formed using a transparent thermoplastic resin, a hot press method or an injection molding method in which a heated mold is pressed against the thermoplastic resin, or a thermoplastic resin monomer is injected into the mold Then, the light transmitting portion 1 can be formed by a casting method for polymerization and solidification. In the case of using an ionizing radiation curable resin, particularly an ultraviolet curable resin, the light transmitting portion 1 is formed by a so-called UV method in which the resin is injected into a mold and irradiated with ultraviolet rays to be cured. Can do. Among these methods, in the present invention, the UV method excellent in mass productivity can be suitably used. According to the UV method, the light transmission part 1 can be continuously manufactured using a mold roll.

  Specifically, for example, as shown in FIG. 5, the base material 3 is fed between a mold roll 50 having a groove corresponding to the shape of the light transmission portion 1 and a nip roll 51 at a predetermined pitch. The arrow in FIG. 5 represents the direction in which the base material 3 is fed. In accordance with the feeding of the base material 3, droplets of the light transmission part forming composition 53 containing, for example, an ultraviolet curable resin or the like are continuously supplied from the supply part 52 between the mold roll 50 and the base material 3. When supplying the light transmissive part forming composition 53 from the supply unit 52 onto the base material 3, the composition reservoir 54 in which the light transmissive part forming composition 53 is accumulated between the mold roll 50 and the base material 3. To be formed. By forming the composition reservoir 54, the light transmitting portion forming composition 53 spreads in the width direction of the substrate 3.

  The light transmitting part forming composition 53 supplied between the mold roll 50 and the base material 3 as described above is formed by the pressing force between the mold roll 50 and the nip roll 51. It is filled between the mold rolls 50. Thereafter, the light transmitting portion forming composition 53 is irradiated with ultraviolet rays by the ionizing radiation irradiation device 55, and the light transmitting portion forming composition 53 is cured to form the light transmitting portion 1. After forming the light transmission part 1, the light transmission part 1 is peeled off from the mold roll 50 through the peeling roll 56.

  The base material 3 fed into the mold roll 50 may include an adhesive layer 6 and a release layer 7 as shown in FIG. The adhesive layer 6 is for adhering the contrast enhancing sheet to the display unit of the display device. The pressure-sensitive adhesive used for the pressure-sensitive adhesive layer 6 is not particularly limited as long as it can transmit light and appropriately adhere another optical sheet. As an adhesive, an acrylic copolymer can be mentioned, for example.

  The release layer 7 is for preventing the adhesive layer 6 from coming into contact with others during handling, and is formed on the adhesive layer 6. Although it does not specifically limit as the peeling layer 7, For example, a polyethylene terephthalate (PET) resin etc. are mentioned.

  In addition, it is preferable that the surface of the groove | channel 1b of the light transmissive part 1 is hydrophilized before the next ink composition filling step. By performing the hydrophilic treatment on the surface of the groove 1b, it becomes easier to fill the groove 1b with the ink composition, and the ink filling rate is improved. The hydrophilization treatment can be performed using a conventionally known method. Examples thereof include dry processes such as low-pressure plasma treatment, atmospheric pressure plasma treatment, corona treatment, ultraviolet irradiation treatment, and excimer lamp treatment, and wet processes such as alkali treatment with sodium hydroxide, potassium hydroxide, ethanolamine, and the like. Among these, atmospheric pressure plasma treatment is preferable from the viewpoint of production efficiency.

  After forming the light transmission part 1 on the base material 3, the ink composition 2 is filled in the groove 1b by using the filling device 10 (FIG. 4B).

  Specifically, first, as shown in FIG. 1, the light transmitting unit 1 is moved while moving the sheet-like light transmitting unit 1 together with the base material 3 by the transport system with respect to the supply unit 20 and the scraping jig 30. The ink composition 2 is continuously supplied from the supply unit 20 to the surface 1a of the ink, and the ink composition 2 on the surface 1a of the light transmission unit 1 is scraped off by a scraping jig 30 located downstream of the supply unit 20. Thereby, the ink composition 2 is filled in the groove 1b, and the excess ink composition 2 present on the surface 1a of the light transmitting portion 1 is scraped off.

  Here, as shown in FIG. 7, the ink composition 2 is supplied from an ink reservoir 2 a containing the ink composition 2 on the upstream side of the first scraping blade 31 and in the immediate vicinity of the first scraping blade 31. Done to form. Specifically, the ink reservoir 2 a can be formed by supplying the ink composition 2 from the supply unit 20 to the surface 1 a of the light transmission unit 1 relatively excessively.

  Further, the scraping by the scraping jig 30 is performed by first scraping the ink composition 2 on the surface 1a of the light transmitting portion by the first scraping blade 31, and then by the second scraping blade 32. The ink composition 2 remaining on the surface 1a is further scraped off. Here, since the scraping jig 30 is used for scraping the ink composition 2, the tip of the first scraping blade 31 is scraped off the surface 1 a of the light transmitting portion 1. The angles α and β of the tip portion 32a of the portion 31a and the second scraping blade 32 are performed in a state of 40 ° to 70 °.

  Further, while the ink composition 2 is supplied from the supply unit 20 and the ink composition 2 is scraped off by the scraping jig 30, a part of the ink composition 2 constituting the ink reservoir 2 a is sucked by the weir unit 36. Suction is performed by the cleaner 41 from the bottom surface 36b side through the hole 36a. The used ink composition sucked from the suction hole 36 a of the weir part 36 is sent to the mixing tank 44 by the pump 42.

  The used ink composition sent to the mixing tank 44 is mixed with the unused ink composition 2 b in the mixing tank 44, and then sent to the supply unit 20 via the filter 46 by the pump 43. Then, it is supplied again from the supply unit 20 to the surface 1 a of the light transmission unit 1.

  After the ink composition 2 is filled in the groove 1b, ionizing radiation is emitted to cure the ink composition 2 in the groove 1b, thereby forming a light absorbing portion 4 having a substantially trapezoidal cross-sectional shape (FIG. 4 ( c)). Thereby, the contrast improvement sheet | seat 5 is produced. As a curing method of the ink composition 2, it can be cured by a normal curing method, that is, irradiation with an electron beam or ultraviolet rays. For example, in the case of electron beam curing, 50 to 50 emitted from various electron beam accelerators such as a Cockloft Walton type, a bandegraph type, a resonant transformation type, an insulating core transformer type, a linear type, a dynamitron type, and a high frequency type An electron beam having an energy of 1000 keV, preferably 100 to 300 keV is used. In the case of ultraviolet curing, ultraviolet rays emitted from rays such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, a metal halide lamp, etc. Available.

  According to the manufacturing method of the scraping jig 30 and the contrast improving sheet 5 of the present embodiment, the scraping jig 30 includes two scraping blades, that is, the first scraping blade 31 and the second scraping blade. 32, the ink composition 2 on the surface 1a of the light transmitting portion 1 is scraped off by the first scraping blade 31, and after filling the groove 1b with the ink composition, the second scraping is further performed. The ink composition remaining on the surface 1a of the light transmitting portion 1 is scraped off by the blade, and the ink composition 2 can be filled in the groove 1b. Thereby, since the ink composition 2 can be reliably filled into the groove 1b, white stripes can be reduced.

  According to the manufacturing method of the scraping jig 30 and the contrast enhancing sheet 5 of the present embodiment, the first scraping blade 31 and the second scraping blade 32 are the first scraping with respect to the surface 1 a of the light transmitting portion 1. Since the angles α and β of the tip 31a of the take-up blade 31 and the tip 32a of the second scraping blade 32 are held by the holder 34 so as to be 40 ° to 70 °, the surface of the light transmitting portion 1 The ink composition 2 on 1a can be reliably scraped off, and scraping defects and black stripe defects can be reduced.

  Furthermore, according to the scraping jig 30 and the method for manufacturing the contrast improving sheet 5 of the present embodiment, it is possible to reduce pitch streaks and black streaks for the following reasons.

  For example, the tip of the second scraping blade is adjusted so that it protrudes more than 0.55 mm from the tip of the first scraping blade, and the tip of the first scraping blade is separated from the surface of the light transmitting portion. When the first scraping blade is disposed so that the tip of the second scraping blade is in contact with the surface of the light transmitting portion, the first scraping blade is disposed. The ink composition stays or clogs in the gap between the take-off blade and the surface of the light transmission part, and density unevenness of the ink composition is formed, which may cause a pitch line defect in the light absorption part. There is.

  Further, the tip of the second scraping blade is adjusted so that it protrudes less than 0.25 mm from the tip of the first scraping blade so that the tip of the first scraping blade contacts the surface of the light transmitting portion. If the second scraping blade is disposed so that the tip of the second scraping blade is separated from the surface of the light transmitting portion, the second scraping blade The scraping property by the ink is poor, the ink composition remains on the light transmission part, and there is a possibility that black stripe defects may occur.

  Further, even when the tip of the second scraping blade is adjusted so that it protrudes from 0.25 mm to 0.55 mm below the tip of the first scraping blade, the tip of the first scraping blade is light. When the first scraping blade is disposed so as to be in contact with the surface of the transmitting portion, and the second scraping blade is disposed so that the tip of the second scraping blade is in contact with the surface of the light transmitting portion. Since the first scraping blade is pushed into the surface of the light transmitting portion, the scraping performance by the second scraping blade is inferior, and there is a risk of black streak failure.

  On the other hand, as in this embodiment, the tip 32b of the second scraping blade 32 is adjusted so as to protrude from the tip 31b of the first scraping blade 31 by 0.25 mm or more and 0.55 mm or less. The first scraping blade 31 is arranged so that the tip 31b of the scraping blade 31 contacts the surface 1a of the light transmitting portion 1, and the tip 32b of the second scraping blade 32 is the surface of the light transmitting portion 1. When the second scraping blade 32 is disposed so as to be separated from 1a, the ink composition 2 is retained or clogged in the gap between the first scraping blade 31 and the surface 1a of the light transmitting portion 1. Can be reduced. Thereby, a pitch line defect can be reduced. Further, since the contact plate 33 is attached to the second scraping blade 32, the movement of the second scraping blade 32 due to the movement of the light transmitting portion 1 can be suppressed, and the second scraping blade 32 The scraping property by 32 can be improved. Thereby, black stripe defects can be reduced.

  In addition, when an ink reservoir is formed, the viscosity of the ink composition constituting the ink reservoir increases with time, or viscosity unevenness occurs in the ink reservoir, which contributes to uneven filling and defective pitch lines. . On the other hand, according to the present embodiment, while the ink composition 2 is continuously supplied, a part of the ink composition 2 constituting the ink reservoir 2a is sucked, and therefore the ink composition constituting the ink reservoir 2a. 2 increase in viscosity and uneven viscosity can be suppressed. Thereby, filling irregularities and pitch streak defects can be reduced.

  The increase in viscosity of the ink composition constituting the ink reservoir causes a shortened life of the ink composition, but according to the present embodiment, since a part of the ink composition 2 constituting the ink reservoir 2a is sucked, An increase in the viscosity of the ink composition 2 can be suppressed, and the life of the ink composition 2 can be extended.

<Contrast improvement sheet>
The contrast improving sheet 5 obtained as described above was formed in the groove 1b, the base material 3, the light transmission part 1 formed on the base material 3 and provided with a plurality of grooves 1b. A light absorbing portion 4.

  The light absorption unit 4 has a refractive index that is the same as or smaller than the refractive index of the light transmission unit 1. Since the refractive indexes of the light transmission unit 1 and the light absorption unit 4 are as described above, the image light from the light source incident on the light transmission unit 1 under a predetermined condition is received by the light absorption unit 4 and the light transmission unit 1. It is possible to provide a bright image to the observer by appropriately reflecting at the boundary surface. Further, since a part of the external light from the observer side is absorbed, the contrast is improved. In addition, stray light that is incident on the inner side of the light absorbing unit 4 without being reflected at the boundary surface between the light transmitting unit 1 and the light absorbing unit 4 is absorbed by the light absorbing material in the light absorbing unit 4. In addition, since the external light from the observer side incident at a predetermined angle can be appropriately absorbed, the contrast can also be improved.

  In addition, two layers of contrast enhancing sheets may be superposed, and in this case, each contrast enhancing sheet may have a different structure. For example, the width, pitch, depth, and shape of the light absorbing portion can be changed between the first layer contrast improving sheet and the second layer contrast improving sheet, or the direction of the light absorbing portion in the thickness direction can be changed. It is possible to change the bias angle of the light absorption part with respect to (the inclination angle of the light absorption part relative to the horizontal direction). Moreover, the material (the kind of resin and the density | concentration of a light absorption particle) which forms a light absorption part can also be changed. For example, the first layer is designed to cut off external light efficiently and focus on improving the contrast, and the second layer is designed to focus on the front brightness improvement effect using reflection. It is preferable.

  The contrast enhancing sheet according to the present invention may include other functional layers employed in conventional optical sheets and viewing angle widening members. Specifically, an antireflection layer, an adhesive layer, an electromagnetic wave shielding layer, a wavelength filter layer, an antiglare layer, a hard coat layer, and the like may be appropriately combined. The order of stacking and the number of stacks of these functional layers can be appropriately determined according to the application.

  The contrast improving sheet according to the present invention can be disposed on a display unit of a display device, for example. Specifically, the contrast improving sheet can be used as an optical filter for a display device, for example. Examples of the display unit of the display device include a plasma display, a liquid crystal display, an organic EL display, a field emission display (FED), a surface conduction electron-emitting device display (SED), and a projection television.

<Optical filter for display device and display device>
Hereinafter, an example in which the contrast improving sheet according to the present invention is attached to a display unit of a display device as an optical filter for the display device will be described. FIG. 8 is a cross-sectional view of a display device provided with a contrast enhancing sheet according to the present embodiment. The display device 60 shown in FIG. 8 includes the contrast enhancing sheet 5 manufactured by the manufacturing method described above. The contrast improving sheet 5 is attached to the display unit 61 of the display device 60 via the adhesive layer 62 so that the base 3 is on the video light source side. On the front side of the contrast improving sheet 5, an antistatic layer 63, an antireflection layer 64, an antiglare layer 65, and the like are disposed. In the present embodiment, the antistatic layer 63 and the like are disposed on the front surface of the contrast enhancing sheet 5, but the present invention is not limited thereto, and a layer that blocks electromagnetic waves, infrared rays, or neon lines may be disposed. .

  Hereinafter, the present invention will be specifically described with reference to examples. In this example, a contrast improving sheet was prepared using the same scraping jig as in the above embodiment and the same method, and the appearance of the contrast improving sheet was observed.

Example 1
<Scraping jig>
A first doctor blade made of metal having a thickness of 200 μm as a first scraping blade, a second doctor blade made of metal having a thickness of 200 μm as a second scraping blade, a first doctor blade, and A scraping jig provided with a holder for holding the second doctor blade was prepared. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 40 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.25 mm, and the distance between the first doctor blade and the second doctor blade was 0.05 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

<Preparation of ink composition>
As photocurable prepolymer, epoxy acrylate oligomer Oxirane, 2,2 '-[(1-methylethylidene) bis (4,1-phenyleneoxymethylene)] bis-, homopolymer, 2-propenoate, 20.0 parts by mass and reactive dilution monomer 20.0 parts by mass of 2-phenoxyethyl acrylate, 20.0 parts by mass of α-acryloyl-ω-phenoxypoly (oxyethylene), and 2- {2- [2- (acryloyloxy) (methyl) ethoxy] Acrylic crosslinked fine particles (manufactured by Ganz Kasei Co., Ltd.) 20.0 containing 13.0 parts by weight of (methyl) ethoxy} (methyl) ethyl acrylate and 25% carbon black having an average particle size of 4.0 μm as light absorbing particles 1 part by weight and 1-hydroxycyclohexyl phenyl ketone (trade name: Irgacure 184, Ciba Specialty Chemicals Co., Ltd.) 7 parts by mass) (made by a formula company) were mixed and homogenized to obtain an ink composition.

  The viscosity of this ink composition at 25 ° C. was 4000 mPa · s. In the present invention, the viscosity was measured based on the rotational viscometer method of JIS K-5400. Specifically, a BL type viscometer manufactured by Tokyo Keiki Co., Ltd. Using a 4-rotor, the value indicated by the viscometer at 12 rpm and 1 minute at 25 ° C. was measured, and a value obtained by multiplying the measured value indicated by the viscometer by a conversion multiplier (500 in this condition) was defined as the viscosity.

In addition, the composition of the ink composition excluding the light-absorbing particles was applied at a thickness of 10 μm, cured by irradiating with 800 mJ / cm ² of ultraviolet light with a high-pressure mercury lamp, and a multi-wavelength Abbe refractometer DR-M4 (stock) The refractive index of 589 nm was measured using a product of Atago Co., Ltd. and found to be 1.547.

<Adjustment of composition for forming light transmitting portion>
Bisphenol A-ethylene oxide 2 mol adduct 41 parts by mass, isophorone diisocyanate 14.0 parts by mass, and bismuth tri (2-ethylhexanoate) (2-ethylhexanoic acid 50% solution)) 0.02 mass as urethanization catalyst The urethane acrylate oligomer obtained by adding 5 parts by mass of 2-hydroxyethyl acrylate and reacting at 80 ° C. for 5 hours was used as a photocurable prepolymer. . This urethane acrylate oligomer 32, 0 parts by mass, 10.0 parts by mass of phenoxyethyl acrylate (molecular weight 192) as a photocurable monomer, and 30.0 masses of diacrylate (molecular weight 512) of EO4 mol adduct of bisphenol A And 0.03 parts by mass of a tetradecanol-ethylene oxide 10-mole adduct as a mold release agent (monoester / diester = molar ratio 1/1), and a tearylamine ethylene oxide 15-mole adduct 02 parts by mass, 3 parts by mass of 1-hydroxycyclohexyl phenyl ketone (trade name: Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) as a photopolymerization initiator, mixed and homogenized to form a light transmission part Got.

The composition for forming a light transmission part was applied at a thickness of 100 μm, and the light transmission part constituent composition was cured by irradiating with 800 mJ / cm ² of ultraviolet light from a high-pressure mercury lamp, and the multiwavelength Abbe refractometer DR-M4 The refractive index of 589 nm was measured using (manufactured by Atago Co., Ltd.) and found to be 1.550.

<Preparation of contrast improving sheet>
The above composition for forming a light transmission part is supplied between a mold having a plurality of grooves corresponding to the light transmission part and a polyethylene terephthalate base material (Toyobo Co., Ltd., A4300, 100 μm). The forming composition was cured to form a light transmission part on the polyethylene terephthalate substrate. And this light transmission part was extracted from the metal mold | die, and the light transmission part by which the some groove | channel was arranged in parallel on the surface was obtained.

  Next, while moving the light transmitting part for each substrate, the ink composition obtained above is continuously supplied from the die head of the die coater to the surface of the light transmitting part so as to be uniformly supplied in the width direction of the light transmitting part. The ink composition on the surface of the light transmission part was scraped off using the above-described scraping jig. The ink composition was supplied so that an ink reservoir was formed on the upstream side of the first doctor blade and in the immediate vicinity of the first doctor blade.

  After filling the groove of the light transmitting portion with the ink composition, the ink composition was irradiated with ultraviolet rays to cure the ink composition, thereby forming the light absorbing portion, and the contrast improving sheet of Example 1 was produced. .

Example 2
In Example 2, a contrast improving sheet was produced using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 2 is a first doctor blade made of metal having a thickness of 200 μm, a second doctor blade made of metal having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 40 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.1 mm, and the distance between the first doctor blade and the second doctor blade was 0.05 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 3
In Example 3, a contrast improving sheet was produced using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 3 is a metal first doctor blade having a thickness of 200 μm, a metal second doctor blade having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 65 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.3 mm, and the distance between the first doctor blade and the second doctor blade was 0.1 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 4
In Example 4, a contrast improving sheet was prepared using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 4 includes a metal first doctor blade having a thickness of 200 μm, a metal second doctor blade having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 65 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.3 mm, and the distance between the first doctor blade and the second doctor blade was 0.6 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 5
In Example 5, a contrast improving sheet was prepared using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 5 is made of a first doctor blade made of metal having a thickness of 200 μm, a second doctor blade made of metal having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 65 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.3 mm, and the distance between the first doctor blade and the second doctor blade was 2.0 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 6
In Example 6, a contrast improving sheet was produced using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 6 includes a metal first doctor blade having a thickness of 200 μm, a metal second doctor blade having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 65 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The tip length of the doctor blade was 0.3 mm, and the distance between the first doctor blade and the second doctor blade was 2.5 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 7
In Example 7, a contrast improving sheet was prepared using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 7 includes a metal first doctor blade having a thickness of 200 μm, a metal second doctor blade having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 65 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.5 mm, and the distance between the first doctor blade and the second doctor blade was 0.6 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 8
In Example 8, a contrast improving sheet was produced using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 8 is a metal first doctor blade having a thickness of 200 μm, a metal second doctor blade having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 65 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.5 mm, and the distance between the first doctor blade and the second doctor blade was 0.05 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 9
In Example 9, a contrast improving sheet was prepared using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 9 includes a metal first doctor blade having a thickness of 200 μm, a metal doctor blade having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 70 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.55 mm, and the distance between the first doctor blade and the second doctor blade was 2.0 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Example 10
In Example 10, a contrast improving sheet was prepared using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Example 10 includes a metal first doctor blade having a thickness of 200 μm, a metal second doctor blade having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 70 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.6 mm, and the distance between the first doctor blade and the second doctor blade was 0.6 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Comparative Example 1
In Comparative Example 1, a contrast improving sheet was prepared using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Comparative Example 1 was provided with a metal doctor blade having a thickness of 200 μm and a holder for holding the doctor blade. In this scraping jig, the angle of the tip of the doctor blade with respect to the surface of the light transmission part was 65 °. The doctor blade was arranged so that the tip of the doctor blade was in contact with the surface of the light transmission part.

Comparative Example 2
In Comparative Example 2, a contrast improving sheet was produced using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Comparative Example 2 is a first doctor blade made of metal having a thickness of 200 μm, a second doctor blade made of metal having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 35 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.3 mm, and the distance between the first doctor blade and the second doctor blade was 0.6 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Comparative Example 3
In Comparative Example 3, a contrast improving sheet was produced using the same composition and the same method as in Example 1 except that a scraping jig different from that in Example 1 was used. The scraping jig used in Comparative Example 3 is a first doctor blade made of metal having a thickness of 200 μm, a second doctor blade made of metal having a thickness of 200 μm, a first doctor blade, and a second doctor blade. And a holder for holding the blade. In this scraping jig, the angles of the tip of the first doctor blade and the tip of the second doctor blade with respect to the surface of the light transmission part are both 75 °, and the second doctor blade has a second angle with respect to the tip of the first doctor blade. The protruding length of the tip of the doctor blade was 0.3 mm, and the distance between the first doctor blade and the second doctor blade was 0.6 mm. In addition, the first doctor blade and the second doctor blade are arranged such that the tip of the first doctor blade is in contact with the surface of the light transmission part and the tip of the second doctor blade is separated from the surface of the light transmission part. Arranged.

Appearance Observation The appearances of the contrast improving sheets of Examples 1 to 5 and Comparative Examples 1 to 5 thus manufactured were observed to confirm the occurrence of white streaks, scraping defects, and black streak defects. The criteria for this evaluation were as follows.

(1) White streak defect A: A white streak defect was not confirmed.
○: Some white streak defects were observed, but there was no practical problem.
X: Many white stripe defects were confirmed.

(2) Scraping failure ◎: Scratching failure was not confirmed.
○: Scratch defects were slightly confirmed, but there was no practical problem.
X: Many scraping defects were confirmed.

(3) Black streak failure A: Black streak failure was not confirmed.
○: Some black streak defects were confirmed, but there was no practical problem.
X: Many black stripe defects were confirmed.

表１に示されるように比較例１に係るコントラスト向上シートは白スジ不良、ピッチスジ不良および黒スジ不良の全てにおいて抑制できなかった。また、比較例１〜３に係るコントラスト向上シートにおいては、白スジ不良、掻き取り不良および黒スジ不良のいずれかを抑制することができたが、これら不良の全てを抑制することができなかった。これに対し、実施例１〜１０に係るコントラスト向上シートにおいては、白スジ不良、掻き取り不良および黒スジ不良の全てを抑制することができた。 The results will be described below.

As shown in Table 1, the contrast improving sheet according to Comparative Example 1 could not be suppressed in all of white line defects, pitch line defects, and black line defects. Moreover, in the contrast improvement sheet | seat which concerns on Comparative Examples 1-3, although any of white stripe defect, scraping defect, and black stripe defect could be suppressed, it was not able to suppress all of these defects. . On the other hand, in the contrast improving sheets according to Examples 1 to 10, it was possible to suppress all of white line defects, scraping defects, and black line defects.

  From these results, according to the scraping jigs of Examples 1 to 10, it was confirmed that all of white stripe defects, scraping defects, and black stripe defects could be suppressed.

  DESCRIPTION OF SYMBOLS 1 ... Light transmission part, 1a ... Surface, 1b ... Groove, 2 ... Ink composition, 2a ... Ink reservoir, 3 ... Base material, 4 ... Light absorption part, 5 ... Contrast improvement sheet, 10 ... Filling device, 20 ... Supply , 30 ... scraping jig, 31 ... first scraping blade, 31a ... tip, 31b ... tip, 32 ... second scraping blade, 32a ... tip, 32b ... tip, 33 ... contact plate, 34 ... Holder, 35 ... Holding part, 35a ... End, 36 ... Weir part, 36a ... Suction hole, 40 ... Ink circulation system, 50 ... Display device.

Claims (15)

A scraping jig used for manufacturing a contrast-enhancement sheet comprising a light transmission part having a plurality of grooves arranged in parallel on the surface and a light absorption part formed in the groove of the light transmission part,
A first scraping blade for scraping off the ink composition supplied onto the surface from the surface of the light transmitting portion in which a plurality of grooves are arranged in parallel on the surface;
A second scraper disposed at a predetermined interval from the first scraping blade and further scraping off the ink composition remaining on the surface of the light transmitting portion after scraping by the first scraping blade; Scraping blade,
A holder for holding the first scraping blade and the second scraping blade,
In the holder, the first scraping blade tip and the second scraping blade tip angle with respect to the surface of the light transmitting portion are 40 ° or more and 70 ° or less, respectively. A scraping jig holding the scraping blade and the second scraping blade.   The holder includes the first scraping blade and the tip of the second scraping blade with respect to the surface of the light transmitting portion so that the angles of the first scraping blade and the second scraping blade are 50 ° or more and 65 ° or less, respectively. The scraping jig according to claim 1, wherein the scraping blade and the second scraping blade are held.   The scraping jig according to claim 1 or 2, wherein an interval between the first scraping blade and the second scraping blade is 0.05 to 2 mm.   The holder is provided at a holding portion that holds the first scraping blade and the second scraping blade, and at both ends in the width direction of the holding portion, and the ink is more than the both ends of the holding portion. The scraping jig according to any one of claims 1 to 3, further comprising a weir portion protruding to the scraping side of the composition for holding an ink reservoir containing the ink composition.   The scraping jig according to claim 4, wherein the weir portion has a suction hole for sucking a part of the ink composition on a bottom surface of the weir portion.   A contrast-enhancement sheet manufacturing apparatus comprising: a light transmitting portion having a plurality of grooves arranged in parallel on a surface; and a light absorbing portion formed in the groove of the light transmitting portion. An apparatus for producing a contrast-enhancing sheet, comprising the scraping jig according to claim 1. A method for producing a contrast-enhancement sheet, comprising: a light transmission part having a plurality of grooves arranged in parallel on a surface; and a light absorption part formed in the groove of the light transmission part,
An ink composition is continuously supplied to the surface of the light transmitting portion while moving a sheet-like light transmitting portion having a plurality of grooves arranged on the surface, and downstream of the ink composition supply position. The ink composition on the surface of the light transmitting portion is formed while forming an ink reservoir containing the ink composition on the upstream side of the first scraping blade disposed in the immediate vicinity of the first scraping blade, Scraping with the first scraping blade and the second scraping blade disposed at a predetermined distance from the first scraping blade on the downstream side of the first scraping blade. ,
The ink composition is scraped so that the angles of the tip of the first scraping blade and the tip of the second scraping blade with respect to the surface of the light transmitting portion are 40 ° or more and 70 ° or less, respectively. The method for producing a contrast-enhancing sheet is performed in a state where the first scraping blade and the second scraping blade are disposed in   The ink composition is scraped so that the angles of the tip of the first scraping blade and the tip of the second scraping blade with respect to the surface of the light transmitting portion are 50 ° or more and 65 ° or less, respectively. The method for producing a contrast-enhancing sheet according to claim 7, wherein the first scraping blade and the second scraping blade are arranged in a state.   The method for producing a contrast enhancing sheet according to claim 7 or 8, wherein a part of the ink composition constituting the ink reservoir is sucked and supplied again to the surface of the light transmission part.   The method for producing a contrast-enhancing sheet according to claim 9, wherein the sucked ink composition is mixed with an unused ink composition and then supplied to the surface of the light supply unit.   The method for producing a contrast-enhancing sheet according to claim 10, wherein a mixing ratio between the sucked ink composition and the unused ink composition is 1: 4 to 4: 1.   The method for producing a contrast-enhancing sheet according to any one of claims 7 to 11, wherein the ink composition is supplied so that the ink composition is supplied uniformly in a width direction of the light transmission portion. .   The method for producing a contrast-enhancing sheet according to claim 7, wherein the ink composition is supplied by a die coating method.   The method for producing a contrast enhancing sheet according to any one of claims 7 to 13, wherein the viscosity of the supplied ink composition is 2500 to 5000 mPa · s.   The method for producing a contrast enhancing sheet according to any one of claims 7 to 14, wherein a shape of the groove of the light transmitting portion is substantially trapezoidal, substantially V-shaped, or substantially rectangular.

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