JP2012198326A - Production method of alignment layer and production method of retardation film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of an alignment layer, which is inexpensive and has excellent alignment regulating power while hardly generating dust or static electricity.SOLUTION: The production method of an alignment layer comprises: a molding step of bringing an alignment layer-forming layer comprising an alignment layer-forming resin composition into contact with an original plate for an alignment layer, the original plate having minute linear concavo-convex structures randomly formed in approximately a given direction formed thereon, then pressurizing so as to transfer the shape on the surface of the original plate for the patterned alignment layer onto the alignment layer-forming layer; a curing step of curing the alignment layer-forming layer after the molding step; and a peeling step of peeling the alignment layer-forming layer from the original plate for the patterned alignment layer.

Description

  The present invention relates to a method for producing an alignment film that has low cost, generates less dust and static electricity, and has an excellent alignment regulating force.

As a conventional general liquid crystal display device, as shown in FIG. 12, there may be mentioned one having an incident-side polarizing plate 102A, an outgoing-side polarizing plate 102B, and a liquid crystal cell 104.
The polarizing plates 102A and 102B are configured to selectively transmit only linearly polarized light (schematically illustrated by arrows in the figure) having a vibration surface in a predetermined vibration direction. They are arranged to face each other in a crossed Nicol state so as to have a right angle relationship with each other.
The liquid crystal cell 104 includes a large number of cells corresponding to the pixels, and is disposed between the polarizing plates 102A and 102B.

  Here, in such a liquid crystal display device 100, the liquid crystal cell 104 has a VA (Vertical Alignment) method in which nematic liquid crystal having negative dielectric anisotropy is sealed (a liquid crystal director is schematically shown by a dotted line in the figure). As an example, the linearly polarized light transmitted through the incident-side polarizing plate 102A is phase-shifted when passing through the non-driven cell portion of the liquid crystal cell 104. And is blocked by the output-side polarizing plate 102B. On the other hand, when passing through the portion of the liquid crystal cell 104 in the driving state, the linearly polarized light is phase-shifted, and an amount of light corresponding to the amount of this phase shift is transmitted through the output-side polarizing plate 102B. Emitted. Thereby, by appropriately controlling the driving voltage of the liquid crystal cell 104 for each cell, a desired image can be displayed on the exit side polarizing plate 102B side. The liquid crystal display device 100 is not limited to the above-described light transmission and blocking modes, and light emitted from the non-driven cell portion of the liquid crystal cell 104 is emitted from the polarizing plate on the emission side. There has also been devised a liquid crystal display device configured so that light emitted from the portion of the cell in the driving state is blocked by the polarizing plate 102B on the emission side while being emitted through 102B.

  By the way, considering the case where linearly polarized light is transmitted through the non-driven cell portion of the VA liquid crystal cell 104 as described above, the liquid crystal cell 104 has birefringence and is refracted in the thickness direction. Since the refractive index and the refractive index in the plane direction are different, the light incident along the normal line of the liquid crystal cell 104 out of the linearly polarized light transmitted through the polarizing plate 102A on the incident side is transmitted without being phase-shifted. Of the linearly polarized light transmitted through the polarizing plate 102 </ b> A, light incident in a direction tilted from the normal line of the liquid crystal cell 104 has a phase difference when passing through the liquid crystal cell 104 and becomes elliptically polarized light. This phenomenon is caused by the fact that the liquid crystal molecules aligned in the vertical direction in the liquid crystal cell 104 act as a positive C plate. Note that the magnitude of the phase difference generated with respect to light transmitted through the liquid crystal cell 104 (transmitted light) depends on the birefringence value of the liquid crystal molecules sealed in the liquid crystal cell 104, the thickness of the liquid crystal cell 104, and the transmitted light. It is also affected by the wavelength.

  Due to the above phenomenon, even when a certain cell in the liquid crystal cell 104 is in a non-driven state, the linearly polarized light is essentially transmitted as it is and should be blocked by the polarizing plate 102B on the output side. A part of the light emitted in the direction inclined from the normal line leaks from the polarizing plate 102B on the emission side.

  For this reason, in the conventional liquid crystal display device 100 as described above, the display quality of the image observed from the direction inclined from the normal line of the liquid crystal cell 104 is mainly lower than the image observed from the front. There was a problem (problem of viewing angle dependency) that it was worsened by doing.

Various techniques have been developed so far to improve the viewing angle dependency problem in the conventional liquid crystal display device 100 as described above, and one of them is disclosed in, for example, Patent Document 1 or Patent Document 2. As shown in the figure, a phase difference layer having a cholesteric regular molecular structure (a phase difference layer exhibiting birefringence) is used, and such a phase difference layer is disposed between the liquid crystal cell and the polarizing plate. There has been known a liquid crystal display device configured to perform the above.
Here, in a phase difference optical element having a cholesteric regular molecular structure, λ = nav · p (p: helical pitch in the helical structure of liquid crystal molecules, nav: average refraction in a plane perpendicular to the helical axis For example, as disclosed in Patent Document 1 or Patent Document 2, the selective reflection wavelength represented by (rate) is adjusted to be smaller or larger than the wavelength of transmitted light.

As a retardation film having such a retardation layer, an alignment film having an alignment regulating force for arranging rod-shaped compounds in a certain direction, and a material having refractive index anisotropy such as a liquid crystal material formed on the alignment film And a phase difference layer including the same. In addition, as a method for imparting alignment regulating force to the alignment film, the alignment film is usually subjected to rubbing treatment (friction).
However, in such a method of imparting alignment regulating force by rubbing treatment, the rubbing treatment on the alignment film surface generates fine dust and static electricity, and as a result, a display device such as a liquid crystal display that requires a clean environment is required. There has been a problem that the manufacturing yield is reduced.
Patent Document 3 discloses a method using a photo-alignment film containing a photo-alignment material as the alignment film. According to such a method, dust and static electricity can be generated, but the photo-alignment material is very expensive, and the polarized ultraviolet light used for aligning such a photo-alignment film Since the irradiation apparatus is also expensive, there is a problem that it is expensive. In addition, there is a problem in that the orientation regulating force tends to be lower than that given by the rubbing treatment.

JP-A-3-67219 JP-A-4-322223 JP 2005-49865 A

  The present invention has been made in view of such a situation, and has as its main object to provide a method for producing an alignment film that has low cost, little dust and static electricity, and has excellent alignment regulating force. is there.

  In order to solve the above problems, the present invention contacts an alignment layer forming layer made of an alignment layer forming resin composition on an alignment layer original plate in which minute line-shaped uneven structures are randomly formed in a substantially constant direction. Then, pressurizing and forming a shape of the surface of the alignment layer precursor on the alignment layer forming layer, a curing step of curing the alignment layer forming layer after the forming step, and the above And a peeling step of peeling the alignment layer forming layer from the alignment layer original plate.

  According to the present invention, an alignment layer having an excellent alignment regulating force capable of arranging rod-shaped compounds in a certain direction is obtained by using an alignment layer original plate in which minute line-shaped uneven structures are randomly formed in a substantially constant direction. The alignment film can be manufactured at a low cost, and dust and static electricity are less generated during manufacturing.

  In the present invention, the alignment layer original plate is preferably a roll plate. This is because it can be continuously formed into an alignment layer forming layer, and an alignment film can be formed easily and in large quantities.

  In this invention, it is preferable that the said peeling process is performed after the said hardening process. By performing the curing step in a state where the original plate and the alignment layer forming layer are in contact with each other, the shape of the original plate surface molded into the alignment layer forming layer can be stably cured, This is because the shape of the surface of the obtained alignment layer can be made highly accurate.

In the present invention, the molding step is performed by coating the alignment layer forming resin composition on the alignment layer original plate to form the alignment layer forming layer, and the alignment layer forming layer. After performing the arrangement | positioning process which arrange | positions a transparent film base material on, what pressurizes, apply | coat the said alignment layer formation resin composition on a transparent film base material, and form the said alignment layer formation layer A layer forming process for forming an alignment layer and a contact process for bringing the alignment layer forming layer into contact with the alignment layer original plate, followed by pressing, or the alignment layer on the alignment layer original plate It is preferable to apply pressure after applying the forming resin composition and performing the filling process for forming the alignment layer forming layer.
This is because an alignment layer capable of arranging rod-shaped compounds in a certain direction can be formed easily and stably.

  In the present invention, the height of the fine line-shaped uneven structure is preferably in the range of 5 nm to 5 μm. This is because rod-like compounds can be stably arranged.

  In the present invention, the viscosity of the alignment layer forming resin composition is preferably in the range of 5 mPa · s to 200000 mPa · s. This is because an alignment layer in which rod-shaped compounds can be arranged in a certain direction can be stably formed.

  In the present invention, the alignment layer-forming resin composition is preferably an ultraviolet curable resin composition. This is because it is possible to easily form an alignment layer in which rod-shaped compounds can be arranged in a certain direction.

  The present invention includes a coating step of applying a retardation layer forming coating solution containing a rod-shaped compound having refractive index anisotropy onto an alignment layer included in the alignment film formed by the above-described alignment film manufacturing method. An alignment step in which the rod-shaped compound contained in the coating film of the retardation layer forming coating solution is arranged along the direction of the minute line-shaped uneven structure formed in the alignment layer, A method for producing a retardation film is provided.

  According to the present invention, by using the alignment film manufactured by the above-described alignment film manufacturing method, it is possible to obtain a retardation film with low cost and less dust and static electricity.

  According to the method for manufacturing an alignment film of the present invention, there is an effect that an alignment film having an excellent alignment regulating force can be obtained at low cost with little generation of dust and static electricity.

It is process drawing which shows an example of the manufacturing method of the oriented film of this invention. It is explanatory drawing explaining the minute line-shaped uneven structure in this invention. It is explanatory drawing explaining the minute line-shaped uneven structure in this invention. It is explanatory drawing explaining the minute line-shaped uneven structure in this invention. It is explanatory drawing explaining the minute line-shaped uneven structure in this invention. It is explanatory drawing explaining the pressurization method in this invention. It is explanatory drawing explaining the pressurization method in this invention. It is a schematic sectional drawing which shows an example of the transparent film base material used for this invention. It is process drawing which shows an example of the manufacturing method of the retardation film of this invention. It is explanatory drawing explaining the other process in this invention. It is explanatory drawing explaining the retardation film obtained by this invention. It is a general | schematic disassembled perspective view which shows the conventional liquid crystal display device.

The present invention relates to a method for producing an alignment film and a method for producing a retardation film using the same.
Hereinafter, the method for producing an alignment film and the method for producing a retardation film of the present invention will be described in detail.

A. First, a method for producing an alignment film of the present invention will be described.
In the method for producing an alignment film of the present invention, an alignment layer forming layer made of an alignment layer forming resin composition is brought into contact with an alignment layer original plate in which minute line-shaped uneven structures are randomly formed in a substantially constant direction. Then, pressurizing to mold the shape of the alignment layer precursor surface on the alignment layer forming layer, and after the shaping step, curing the alignment layer forming layer and the alignment And a peeling step of peeling the layer forming layer from the alignment layer original plate.

Such a method for producing an alignment film of the present invention will be described with reference to the drawings. FIG. 1 is a process diagram showing an example of a method for producing an alignment film of the present invention. First, as illustrated in FIG. 1A, the alignment layer forming resin composition is applied on the transparent film substrate 1 to form the alignment layer forming layer 2 ′, and the alignment layer forming layer is formed. The layer 2 ′ is brought into contact by being placed on a roll plate (original plate) 10 in which minute line-shaped uneven structures are randomly formed in a substantially constant direction, and then pressed by a pressure roll (FIG. 1). (B)) The fine line-shaped uneven structure of the roll plate 10 was formed on the alignment layer forming layer 2 ′, and then contacted on the roll plate 10 with respect to the alignment layer forming layer 2 ′. By irradiating with ultraviolet rays in the state (FIG. 1C), the alignment layer forming layer is cured, and the alignment layer forming layer 2 ′ is peeled from the roll plate 10 to thereby form the transparent film substrate 1 and the transparent film. An alignment film 20 having an alignment layer 2 formed on the film substrate 1 is obtained (FIG. 1). d)).
In this example, FIGS. 1A to 1B are molding steps, FIG. 1C is a curing step, and FIG. 1D is a peeling step.

According to the present invention, by using an alignment layer original plate in which minute line-shaped concavo-convex structures are randomly formed in a substantially constant direction, an alignment in which excellent alignment regulating force for arranging rod-shaped compounds in a desired direction is formed. An alignment film having a layer can be formed easily and at low cost.
Further, since the alignment layer forming layer itself is not subjected to rubbing treatment, generation of dust and static electricity during production can be reduced.

The method for producing an alignment film of the present invention includes at least a shaping step, a curing step, and a peeling step.
Hereinafter, each process of the manufacturing method of the oriented film of this invention is demonstrated in detail.

1. Forming step The forming step in the production method of the present invention is for forming an alignment layer comprising an alignment layer forming resin composition on an alignment layer original plate in which minute line-shaped uneven structures are randomly formed in a substantially constant direction. In this step, the layers are brought into contact with each other and then pressurized, and the shape of the alignment layer original plate surface is formed on the alignment layer forming layer.

(1) Alignment layer original plate The alignment layer original plate (hereinafter sometimes referred to simply as the original plate) used in this step is one in which minute line-shaped uneven structures are randomly formed in a substantially constant direction.
In this step, by forming such a fine line-shaped uneven structure on the alignment layer forming layer by pressurization, the surface has a fine line-shaped uneven structure corresponding to this shape. An alignment layer capable of arranging the compounds in a certain direction can be formed.

  The shape of the original plate may be a plate shape, but is preferably a roll shape, that is, the original plate is preferably a roll plate. This is because it can be continuously formed into an alignment layer forming layer, and an alignment film can be formed easily and in large quantities.

  The fine line-shaped uneven structure formed on the original plate in this step is formed into an alignment layer forming layer by pressing, and a retardation layer containing a rod-shaped compound on the alignment layer formed according to the present invention. Is formed in order to align the rod-shaped compounds contained in the retardation layer in a certain direction.

  The minute line-like uneven structure in the present invention is randomly formed in a substantially constant direction. For example, the line-like unevenness such as a minute scratch formed when the surface is rubbed. The structure is formed in a substantially constant direction.

When the minute line-shaped uneven structure in this step is randomly formed in a substantially constant direction, the width, height, and period of the line-shaped uneven structure are particularly limited as long as the rod-shaped compound can be arranged. Is not to be done. In particular, in the present invention, the width of the fine line-shaped uneven structure is preferably in the range of 1 nm to 100 μm, more preferably in the range of 1 nm to 50 μm, particularly 1 nm to 10 μm. More preferably, it is within the range.
The height of the fine line-shaped uneven structure is preferably within a range of 5 nm to 5 μm, more preferably within a range of 5 nm to 3 μm, and particularly within a range of 5 nm to 1 μm. Preferably there is.
Further, the period of the fine line-shaped uneven structure is preferably in the range of 0.5 nm to 50 nm, more preferably in the range of 0.5 nm to 30 nm, and particularly in the range of 0.5 nm to 10 nm. It is preferable to be within. It is because a rod-shaped compound can be stably arranged because the minute line-shaped uneven structure has the above-mentioned size.

  Here, the height, width, and period of the minute line-shaped concavo-convex structure mean distances indicated by l, m, and n in FIG.

The direction in which the fine line-shaped concavo-convex structure is formed in the present invention is appropriately set depending on the type of alignment film manufactured by the manufacturing method of the present invention.
In this step, when the original plate is a roll plate, it can be set to 0 °, 45 °, 90 °, 135 °, etc. with respect to the rotation direction of the roll.
FIG. 3 shows the roll plate surface when the direction in which the fine line-shaped uneven structure is formed is 45 °, FIG. 4 is 0 °, and FIG. 5 is 90 °.
3 to 5 indicate the same members as those in FIG. 1, and a description thereof will be omitted here. Moreover, the arrow in a figure shows the formation direction of a fine line-shaped uneven structure.

  The material of the original plate in this step is not particularly limited as long as it can form the above-mentioned surface shape with high accuracy. For example, it may be an inorganic material such as a metal, and a resin or the like is used. It may be present, but is preferably a metal material.

The material used in this step is not particularly limited as long as a fine line-shaped uneven structure can be formed on the surface, but nickel, stainless steel, tinplate, iron, copper, silver, gold, chromium, zinc , Silicon, titanium, tantalum, tin, aluminum, nickel-phosphorous and alloys thereof, metal materials such as alumite, titanium oxide (TiO ₂ , Ti ₃ O ₅ ), tantalum oxide (Ta ₂ O ₅ ), silicon oxide (SiO ₂ ) , SiO ₂ ), tin oxide (SnO ₂ ), aluminum oxide (Al ₂ O ₃ ), chromium oxide (Cr ₂ O ₃ ), barium titanate (BaTiO ₃ ), indium oxide (In ₂ O ₃ ), zinc oxide ( ZnO, metal oxides such as _{ZnO 2), TiC, SiC,} BC, carbides such as WC, TiN, SiN, CrN, BN, AIN, CN, Zr Nitrides such as, barium fluoride _(BaF 2), magnesium fluoride _(MgF 2), magnesium oxide (MgO), diamond-like carbon (DLC), glassy carbon, ceramic, silicon nitride, an inorganic material carbon nitride Among them, nickel, copper, chromium, stainless steel, diamond-like coating, carbide like TiC, SiC, BC, WC, nitride like TiN, SiN, CrN, BN, AIN, CN, ZrN Preferably there is. This is because a fine line-shaped uneven structure can be easily formed on the surface. Moreover, since it is excellent in peelability, the alignment layer forming layer after this step can be easily peeled off.

The shape of the base material in this step is not particularly limited as long as a fine line-shaped uneven structure can be formed on the surface, but it can be a plate shape, a roll shape, a sleeve shape, etc. However, a roll shape, a sleeve shape, or the like is preferable, and a sleeve shape is particularly preferable. By being in a roll shape such as a roll shape or a sleeve shape, the original plate can be made into a roll plate, and can be formed into an alignment layer forming layer continuously while rotating the original plate, that is, easily and in large quantities This is because the alignment film can be formed and the manufacturing efficiency can be increased. Further, in the present invention, since no special equipment is required, it can be manufactured relatively easily and inexpensively.
In addition, because of the sleeve shape, the alignment film can be produced with high production efficiency using the original plate of the present invention. Further, the sleeve-shaped original plate is advantageous in that it is lighter than the roll-shaped original plate and easy to handle.
Here, specifically as a roll-shaped base material, a roll with a shaft, a pipe without a shaft, etc. can be mentioned. Here, the shaftless pipe refers to a cylindrical base material having a thickness of 3000 μm or more.
The sleeve shape represents a strip of a seamless base material, and the sleeve-shaped base material can be easily deformed by air pressure or stress, and specifically, a cylinder having a thickness of 1000 μm or less. It refers to a shaped substrate.
In this step, in the case of a roll shape such as a roll shape or a sleeve shape, it is preferable that the seamless shape is seamless, but a plate-like base material having a cylindrical seam can also be used.

  In addition, the method for forming such an original plate is not particularly limited as long as it is a method capable of forming a fine line-shaped uneven structure with high accuracy. For example, a base material is prepared, and the surface of the base material is prepared. A method of performing a polishing process for forming a fine line-shaped uneven structure by polishing in a substantially constant direction can be given.

  The polishing method is not particularly limited as long as it is a method capable of forming a fine line-shaped uneven structure so that rod-like compounds can be arranged, but grinding wheel polishing, paper polishing, tape polishing, sand blasting method, shot blasting method, Blasting method such as grit blasting method, glass bead blasting method, brush graining method using brush materials such as synthetic resin hair, nonwoven fabric, animal hair, steel wire such as nylon, polypropylene, vinyl chloride resin, metal wire Wire graining method, brush polishing method while supplying slurry containing abrasive (brush graining method), ball grain method, buffing method such as liquid honing method, shot peening method, rotary barrel Barrel polishing method using a vibrating barrel, Luther polishing method, Grain flow polishing, electrolytic polishing, chemical polishing, chemical composite polishing, composite electrolytic polishing, chemical mechanical polishing method and a CMP polishing method or the like. In this step, it is particularly preferable that the polishing residue does not accumulate. In particular, a tape polishing method, a brush graining method, or the like is preferable. This is because a minute line-shaped uneven structure can be formed with high accuracy. Further, it is possible to prevent molding defects due to the remaining polishing residue.

(2) Orientation layer formation layer The orientation layer formation layer used for this process consists of a resin composition for orientation layer formation.

The resin composition for forming an alignment layer used in this step is not particularly limited as long as the surface shape of the original plate can be shaped by applying pressure after contacting the original plate. Examples include ionizing radiation curable resin compositions, thermosetting resin compositions, electron beam curable resin compositions, and thermoplastic resin compositions.
Any of these constituent materials can be suitably used in this step, but among these, an ionizing radiation curable resin composition is preferably used. This is because by using the ionizing radiation curable resin composition, a product with high productivity can be obtained. When an ionizing radiation curable resin composition is used as the alignment layer forming resin composition, the alignment layer formed according to the present invention is composed of a cured ionizing radiation curable resin composition.

  Specific examples of the ionizing radiation curable resin composition used in the present invention include, for example, polymerizable oligomers and monomers having an acryloyl group such as urethane acrylate, epoxy acrylate, polyester acrylate, polyether acrylate, melamine acrylate, and acrylic acid. , Acrylamide, Acrylonitrile, Styrene, Polymerizable oligomers with polymerizable vinyl groups, Monomers, etc., or a mixture of them, and photopolymerization initiators added to additives such as sensitizers as necessary The thing etc. can be mentioned. Moreover, you may contain a solvent as needed.

  Such a solvent is not particularly limited as long as it can uniformly dissolve or disperse the monomer and the like. Examples thereof include hydrocarbon solvents such as benzene and hexane, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. Ketone solvents, ether solvents such as tetrahydrofuran and 1,2-dimethoxyethane, alkyl halide solvents such as chloroform and dichloromethane, ester solvents such as methyl acetate, ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, Examples include amide solvents such as N, N-dimethylformamide, sulfoxide solvents such as dimethyl sulfoxide, anone solvents such as cyclohexane, and alcohol solvents such as methanol, ethanol, and propanol. That is, the present invention is not limited to these. Further, the solvent used in this step may be one kind or a mixed solvent of two or more kinds of solvents.

  Moreover, as a thermosetting resin composition and a thermoplastic resin composition, what contains an acrylic resin, a fluorine resin, a polyester resin, a polycarbonate resin, a cycloolefin resin, a cycloolefin copolymer resin etc. can be used.

  In addition, the alignment layer forming resin composition used in this step absorbs, as necessary, an antioxidant for suppressing changes to oxygen, a light stabilizer for suppressing changes to light, and ultraviolet light. Even if it contains an ultraviolet absorber, a viscosity modifier for adjusting the viscosity, a refractive index modifier for adjusting the refractive index, a fluorine-based or silicon-based lubricant for improving moldability, etc. good.

The viscosity of the alignment layer forming resin composition used in this step is not particularly limited as long as the shape of the original plate surface can be molded into the alignment layer forming layer by pressing. For example, at 25 ° C., it is preferably within a range of 5 mPa · s to 200000 mPa · s, more preferably within a range of 10 mPa · s to 100000 mPa · s, particularly 30 mPa · s to 3000 mPa · s. More preferably, it is in the range.
In the case of a melt-type resin, for example, the melt flow index (MFI) at 190 ° C. is preferably 0.1 g / 10 min or more, and in particular, 1.0 g / 10 min or more. Particularly preferably 5.0 g / 10 min or more. This is because when the viscosity is within the above range, the moldability can be improved.

  The thickness of the alignment layer forming layer used in this step is not particularly limited as long as the surface shape of the original plate can be accurately shaped. It can be the same as the orientation layer of the phase difference film. Specifically, it can be in the range of 0.5 μm to 20 μm.

(3) Molding step In this step, the alignment layer forming layer made of the alignment layer forming resin composition is brought into contact with the original plate and then pressed, and the shape of the surface of the original plate is applied to the alignment layer forming layer. Is a process of shaping.

  The pressure applied at the time of pressurization in this step is not particularly limited as long as it can stably shape the surface shape of the original plate on the alignment layer forming layer, and is used in this step. The orientation layer forming resin composition is appropriately selected according to the viscosity and the like, and using the orientation layer forming resin composition and the original plate, the extent of the shape of the original plate to the orientation layer forming layer is determined. It can be shaped or found by repeating experiments while adjusting the pressure. For example, when the alignment layer-forming resin composition having the above-described viscosity is used, the pressure is preferably in the range of 10 MPa / cm to 2000 MPa / cm, and more preferably 100 MPa / cm to 1000 MPa / cm. It is preferably within the range, and particularly preferably within the range of 150 MPa / cm to 500 MPa / cm. If the pressure is too low, the alignment layer forming layer does not enter the original plate so much that the height of the convex structure in the fine line-shaped uneven structure may be insufficient. If the thickness is too high, the alignment layer forming layer may enter the original plate too much and may not come out of the original plate.

In this step, the method for pressurizing the pressure is not particularly limited as long as the surface shape of the original plate can be stably formed on the alignment layer forming layer. For example, a belt press method, a roll A method using a touch method or the like can be given.
Hereinafter, a method of applying the pressure to the alignment layer forming layer using these methods will be described with reference to the drawings.

FIG. 6 is an explanatory view for explaining a pressurizing method according to the present invention. FIG. 11 exemplifies a method of pressurizing by a roll touch method. The unwinding machine 51a for unwinding the transparent film substrate 1 and the alignment layer forming layer 2 ′ are discharged by discharging the alignment layer forming resin composition. The alignment layer forming die 53 to be formed, the ultraviolet irradiation device 55 for irradiating the alignment layer forming layer 2 ′ with ultraviolet rays, the peeling roll 52 for peeling the alignment layer forming layer from the roll plate 10, and the alignment film 20 And using an alignment film manufacturing apparatus having a pressure roll 50 having elasticity such as rubber for pressing the alignment layer forming layer 2 ′ to the roll plate 10. The method is illustrated. In the roll touch method, since the pressure roll is deformed by using a pressure roll having elasticity such as rubber, the contact time between the roll plate and the alignment layer forming layer can be extended. It becomes possible to stably mold a desired minute line-shaped uneven structure on the forming layer.
Moreover, FIG. 7 is explanatory drawing explaining the pressurization method in this invention. FIG. 12 exemplifies a method of applying pressure by a belt press method, and an alignment layer forming die 53 for discharging an alignment layer forming resin composition directly onto the roll plate 10 and an alignment belt 56. The method of pressurizing using a film manufacturing apparatus is illustrated. In the belt press method, when a roll plate is used as an original plate, a pressure can be applied to the alignment layer forming layer by confronting the roll plate and the pressure belt. Since the belt press method can increase the contact time between the roll plate and the alignment layer forming layer, it is possible to stably mold a desired fine line-shaped uneven structure on the alignment layer forming layer. .
Note that reference numerals not described in FIG. 7 can be the same as those in FIG. 6, and thus description thereof is omitted here.

The forming method in this step is not particularly limited as long as the surface shape of the original plate can be accurately formed on the alignment layer forming layer, but the alignment layer is formed on the alignment layer original plate. A method of applying pressure after applying a forming resin composition and performing a filling process for forming the alignment layer forming layer and an arrangement process for disposing a transparent film substrate on the alignment layer forming layer. (First embodiment) An alignment layer forming layer forming process for coating the alignment layer forming resin composition on a transparent film substrate to form the alignment layer forming layer, and the alignment layer forming layer. And a contact treatment for contacting the alignment layer original plate, and a method of applying pressure after the contact treatment (second embodiment), applying the alignment layer forming resin composition on the alignment layer original plate, and How to pressurize after filling process to form alignment layer forming layer It is preferably (third embodiment). This is because a minute line-shaped uneven structure can be stably formed.
Hereinafter, such a molding method will be described.

(A) 1st embodiment The shaping method of this aspect is the filling process which coats the said resin composition for orientation layer formation on the said original plate, and forms the said layer for orientation layer formation, and the object for said orientation layer formation And a placement process of placing a transparent film substrate on the layer, followed by pressurization. By shaping by such a shaping method, an alignment film in which an alignment layer is laminated can be easily formed on a transparent film substrate.

  The transparent film substrate used in this embodiment is not particularly limited as long as it is made of a resin material and has a predetermined transparency. Especially, it is preferable that the transparent film base material used for this invention is a thing with low phase difference property. More specifically, the transparent film substrate used in the present invention preferably has an in-plane retardation value (Re value) in the range of 0 nm to 10 nm, and preferably in the range of 0 nm to 5 nm. More preferably, it is further in the range of 0 nm to 3 nm. When the in-plane retardation value of the transparent substrate is larger than the above range, for example, the display quality of the 3D display device obtained when the 3D display device is manufactured using the alignment film manufactured by the manufacturing method of the present invention. This is because it may become worse.

  The transparent film substrate used in this embodiment preferably has a transmittance in the visible light region of 80% or more, and more preferably 90% or more. Here, the transmittance | permeability of a transparent film base material can be measured by JISK7361-1 (the test method of the total light transmittance of a plastic-transparent material).

  Examples of the transparent film substrate used in this embodiment include acetyl cellulose resins such as triacetyl cellulose, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, olefin resins such as polyethylene and polymethylpentene, and acrylic resins. Resin, polyurethane resin, polyethersulfone, polycarbonate, polysulfone, polyether, polyetherketone, (meth) acrylonitrile, cycloolefin polymer, cycloolefin copolymer, etc. Since the in-plane retardation of the film substrate is likely to approach zero, resins such as acetyl cellulose resins, cycloolefin polymers, cycloolefin copolymers, and acrylic resins are preferred.

  About the thickness of a transparent film base material, it can determine suitably according to the use of the orientation film manufactured with the manufacturing method of this invention, the material which comprises a transparent film base material, etc., and it is specifically limited However, usually, it is preferably in the range of 20 μm to 188 μm, and more preferably in the range of 30 μm to 90 μm.

  In addition, when the said orientation layer consists of ultraviolet curable resin, you may form the primer layer for improving the adhesiveness of a transparent film base material and an ultraviolet curable resin on a transparent film base material. This primer layer may be any layer that has adhesiveness to both the transparent film substrate and the ultraviolet curable resin, is visible optically transparent, and allows ultraviolet light to pass through. Polymer type and urethane type can be used.

  As a transparent film base material in this aspect, you may have an anti-glare layer or the antireflection layer 5 etc. on the surface opposite to the surface in which the said orientation layer is formed so that it may illustrate in FIG. Can be mentioned. This is because, when a display device is manufactured, a retardation film capable of obtaining a display device with good display quality can be formed.

  In this aspect, since such an antireflection layer is formed, when a liquid crystal display device is manufactured using an alignment film manufactured by the manufacturing method of the present invention, a liquid crystal display device with good display quality is obtained. There is an advantage that can be obtained. Note that only one or both of the antireflection layer and the antiglare layer may be used.

  The antiglare layer is a layer having a function of reducing screen reflection caused by external light from the sun, a fluorescent lamp, or the like entering and reflecting on the display screen of the display device. On the other hand, the antireflection layer improves the image contrast by suppressing the regular reflectance of the surface, and as a result, has a function of improving the visibility of the image. The antiglare layer and antireflection layer used in this embodiment are not particularly limited as long as they have a desired antiglare function or antireflection function, and are used for display devices for the purpose of improving display image quality. Generally known ones can be used. Examples of the antiglare layer include a resin layer in which fine particles are dispersed, and examples of the antireflection layer include a layer having a configuration in which a plurality of layers having different refractive indexes are stacked. . If an antireflection layer is provided on the outermost surface of the antiglare layer, the visibility of the image in the bright room can be further improved.

The method for coating the alignment layer forming resin composition on the original plate performed in the filling process in this embodiment is not particularly limited as long as it can form an alignment layer forming layer having a uniform thickness. For example, a roll coating method, a T-die coating method, a cast coating method, a blade coating method, a bar coating method, a wire bar coating method, or a known method can be used.
In this embodiment, among them, a method that does not require the addition of a solvent to the alignment layer forming resin composition is preferable, and in particular, a melt extrusion method and a non-sol coating method can be preferably used. It is because a drying process etc. can be made unnecessary and it can be excellent in process passage property.
Here, as the melt extrusion method, for example, a method in which the alignment layer forming resin composition is thermally melted in a temperature range of not less than the glass transition temperature and not more than the thermal decomposition temperature, and extruded using a T die, etc. Is mentioned.
In addition, after the filling process, a drying process or a half-cure process using heat, UV, or EB can be appropriately performed.

  As a method of disposing the transparent film substrate on the alignment layer forming layer performed in the disposition treatment in this aspect, any method can be used that allows the alignment layer forming layer and the transparent film substrate to sufficiently adhere to each other. The method is not particularly limited, and examples thereof include a method in which a roll-shaped transparent film substrate is continuously unwound on the alignment layer forming layer on the original plate.

(B) 2nd embodiment The shaping method of this aspect is the layer formation process for alignment layer formation which coats the said resin composition for alignment layer formation on a transparent film base material, and forms the said layer for alignment layer formation. And a contact treatment for bringing the alignment layer forming layer into contact with the original plate, followed by pressurization. By being such a shaping method, a retardation film in which an alignment layer is laminated on a transparent film substrate can be easily formed.
In this case, the alignment layer forming resin may contain a solvent compatible with the alignment layer forming resin. When it contains a solvent, it is desirable to apply a drying treatment for evaporating the solvent after coating the alignment layer-forming resin composition on the transparent film substrate. In addition, as a solvent, a solvent permeation layer can be formed between the transparent film substrate and the alignment layer forming layer by penetrating into the transparent film substrate, and therefore occurs at the interface between the transparent film substrate and the alignment layer. It is possible to prevent the wiggle and poor adhesion.

  The method for coating the alignment layer-forming resin composition on the transparent film substrate performed in the alignment layer-forming layer forming treatment in this embodiment is a method that can form an alignment layer-forming layer having a desired thickness. What is necessary is just to be the same as the filling process as described in the above-mentioned section “(a) First embodiment”.

  The method for bringing the alignment layer forming layer performed in the contact treatment in this embodiment into contact with the original plate is particularly limited as long as the alignment layer forming layer can be sufficiently adhered to the original plate. Instead, it can be the same as the placement process described in the section “(a) First Embodiment”.

(C) Third Embodiment The molding method of this aspect is a method in which the alignment layer-forming resin composition is applied on the original plate, and after the filling treatment for forming the alignment layer-forming layer, pressurization is performed. Is the method. By such a shaping method, for example, an alignment film composed only of an alignment layer can be easily obtained.
The method of coating the alignment layer forming resin composition on the original plate performed in the filling process in this embodiment is particularly limited as long as the alignment layer forming layer having a desired thickness can be formed. However, it may be the same as the filling process described in the section “(a) First embodiment”.

(4) Alignment region The alignment region formed in the alignment layer forming layer by carrying out this step is obtained by shaping the surface shape of the original plate.
Therefore, each of the alignment regions formed in the alignment layer forming layer has a fine line-like uneven structure corresponding to the fine line-like uneven structure of the original.
For this reason, when a roll original plate having a fine line-shaped uneven structure formed in a direction of 90 ° with respect to the rotation direction of the roll as the original plate is molded into a long alignment layer forming layer, Such a line-shaped uneven structure is formed in a direction of 90 ° with respect to the longitudinal direction (long direction).

2. Curing Step The curing step in the production method of the present invention is a step of curing the alignment layer forming layer after the shaping step.

  In this step, the method for curing the alignment layer forming layer is appropriately selected according to the alignment layer forming resin composition constituting the alignment layer forming layer. When the forming resin composition is an ionizing radiation curable resin composition, examples include an ultraviolet curing method and an electron beam curing method. When the alignment layer forming resin composition is a thermosetting resin composition, heating is performed. Examples thereof include a curing method and a normal temperature curing method. Moreover, when using a thermoplastic resin composition as the said resin composition for alignment layer formation, it can be made to harden | cure by the cooling method which makes a cooling roll etc. contact.

  As a method of irradiating with ultraviolet rays in the ultraviolet curing method in this step, a method of irradiating from the surface opposite to the surface in contact with the original of the alignment layer forming layer is usually used. If necessary, a method of irradiating from the surface in contact with the original plate may be used as necessary. This is because it can be sufficiently cured in a short time.

In the case of curing by an ultraviolet curing method in this step, the curing rate (reaction rate) of the alignment layer forming layer is preferably in the range of 20% to 97%, and more preferably in the range of 30% to 90%. It is preferable to be within. When the obtained pattern alignment film is stored, fine irregularities and patterns are crushed, resulting in shape defects, bleeding is likely to occur, and the liquid crystal coating surface side of the alignment layer is contaminated, causing liquid crystal alignment defects. This is because such a problem can be prevented. Another advantage is that it is possible to ensure adhesion to the liquid crystal layer.
In addition, the curing rate is the reactivity included in the alignment layer forming layer before performing this step X times the number of moles of reactive functional groups contained in the alignment film after performing this step. When the mole number of the functional group is Y, it is represented by (XY) / X × 100 (%).

In this step, the alignment layer forming layer may be heated when the ultraviolet ray is irradiated by the ultraviolet curing method. This is because the reaction efficiency can be improved.
In this step, the method for heating the alignment layer forming layer is not particularly limited as long as it can bring the alignment layer forming layer to a desired temperature, and a known heating method may be used. Specific examples include a method using a temperature-adjustable original plate and a method using an infrared irradiation device, a hot air blower, and the like.

3. Peeling process The peeling process in the manufacturing method of this invention is a process of peeling the said layer for alignment layer formation from the said original plate.
The peeling method in this step is not particularly limited as long as the original can be peeled without damaging the cured alignment layer forming layer, that is, the alignment layer. Specifically, a method of peeling using a peeling roll as shown in FIG. 6 or FIG.

  The order of performing this step is not particularly limited as long as it is performed after the shaping step, but is preferably performed after the curing step. By performing the curing step in a state where the original plate and the alignment layer forming layer are in contact with each other, the shape of the original plate surface molded into the alignment layer forming layer can be stably cured, This is because the shape of the surface of the obtained alignment layer can be made highly accurate.

4). Method for Producing Alignment Film The production method of the present invention includes the molding step, the curing step, and the peeling step, but may include other steps as necessary.
Examples of such other processes include a winding process for winding the alignment film obtained after the peeling process into a roll, and a cleaning process for regularly cleaning the surface of the original.
Moreover, you may have a lamination process which laminates | stacks a transparent film base material on the said orientation layer as needed. In addition, as a lamination | stacking method of an orientation layer and a transparent film base material, like the above-mentioned orientation layer formation layer formation process, the method of coating the orientation layer formation resin composition on a transparent film base material, or the said orientation Examples thereof include a method in which a transparent film substrate is thermocompression-bonded to the layer and a method in which the transparent film substrate is bonded through an adhesive or the like.

Furthermore, you may have a 2nd hardening process for more fully hardening the layer for alignment layer formation after the said hardening process and peeling process. This is because the pattern alignment film can be made more excellent in hardness. Further, the time required for the curing step and the peeling step can be shortened, and the process can be made highly flexible.
Specifically, when the alignment layer-forming resin composition is an ionizing radiation-curable resin composition, the surface that contacts the original of the alignment layer-forming layer using an ultraviolet curing method as the curing step. After curing and transferring the surface shape, the alignment layer forming layer is peeled from the original plate by the peeling step, and then, as a second hardening step, the surface of the alignment layer forming layer that is in contact with the original plate. Ultraviolet irradiation can be performed.
In the case where the alignment layer forming resin composition is a resin composition having ionizing radiation curability and thermoplasticity, first, after performing the shaping step in a state of being heated and melted, After curing the surface in contact with the original of the alignment layer forming layer using a cooling method as a curing step and transferring the surface shape, the alignment layer forming layer is released from the original by the peeling step, and then As the second curing step, an ultraviolet curing method in which ultraviolet irradiation is performed on the surface of the alignment layer forming layer that is in contact with the original plate can be used.

The curing method for the alignment layer forming layer in the second curing step can be the same as in the curing step.
The ultraviolet irradiation method used in the ultraviolet curing method in this step may be a method of irradiating from the surface in contact with the original of the alignment layer forming layer or a method of irradiating from the opposite surface of the contact surface, but the above contact It is preferable that it is the method of irradiating from the surface to perform. This is because the alignment layer can maintain the surface shape of the original plate more stably.

5. Alignment film The alignment film obtained by the production method of the present invention has at least an alignment layer, but usually has a transparent film substrate.
Further, as described above, it may have an antireflection layer or an antiglare layer.

  As an application of the alignment film obtained by the production method of the present invention, it can be used for a retardation film, and in particular, it is easily affected by dust and static electricity and used for a display device that is required to be low in cost. It is suitably used for a retardation film.

B. Next, a method for producing the retardation film of the present invention will be described.
The retardation film manufacturing method of the present invention is a retardation layer forming coating solution comprising a rod-like compound having refractive index anisotropy on an alignment layer contained in an alignment film formed by the above-described alignment film manufacturing method. An alignment step of aligning the rod-shaped compound contained in the coating film of the retardation layer forming coating solution along the direction of the fine line-shaped uneven structure formed in the alignment layer; It is characterized by having.

  The method for producing the retardation film of the present invention will be described with reference to the drawings. FIG. 9 is a process diagram showing an example of a method for producing a retardation film of the present invention. As illustrated in FIG. 9, the retardation film manufacturing method of the present invention is formed by the above-described alignment film manufacturing method, and is formed in accordance with the fine line-shaped uneven structure of the alignment layer original plate. A coating film is formed by applying a coating solution for forming a retardation layer containing a rod-like compound having refractive index anisotropy onto the alignment layer 2 in which a linear concavo-convex structure is randomly formed in a substantially constant direction ( FIG. 9A), by heating the coating film 3 ′, the rod-like compounds contained in the coating film 3 ′ are arranged along the direction of the minute line-shaped uneven structure formed in the alignment layer 2. In this way (FIG. 9B), a retardation layer 3 containing rod-shaped compounds arranged in the same direction as the fine line-shaped uneven structure formed in the alignment layer 2 is formed to obtain a retardation film 30. (FIG. 9C).

  According to the present invention, by using the alignment film manufactured by the above-described alignment film manufacturing method, it is possible to obtain a retardation film with low cost and less dust and static electricity.

The method for producing a retardation film of the present invention is characterized by having at least a coating step and an orientation step.
Hereinafter, each process of the manufacturing method of the retardation film of this invention is demonstrated in detail.

1. Coating process The coating process in the present invention comprises a coating solution for forming a retardation layer containing a rod-shaped compound having refractive index anisotropy on an alignment layer included in an alignment film formed by the above-described method for manufacturing an alignment film. It is a process of applying.
The alignment film is the same as that described in the above section “A. Method for manufacturing alignment film”, and thus the description thereof is omitted here.

  The rod-shaped compound contained in the retardation layer forming coating solution used in this step has refractive index anisotropy and is randomly formed in a substantially constant direction on the surface of the alignment region, that is, the alignment layer. There is no particular limitation as long as a desired retardation can be imparted to the retardation layer in this step by arranging regularly along the alignment regulating force of the fine line-shaped uneven structure. Especially, it is preferable that the rod-shaped compound used for this process is a liquid crystalline material which shows liquid crystallinity. This is because the liquid crystalline material has a large refractive index anisotropy, so that it becomes easy to impart a desired retardation to the retardation film produced by the production method of the present invention.

  As said liquid crystalline material used for this process, the material which shows liquid crystal phases, such as a nematic phase and a smectic phase, can be mentioned, for example. In this step, any material exhibiting any of these liquid crystal phases can be suitably used, but it is particularly preferable to use a liquid crystalline material exhibiting a nematic phase. This is because a liquid crystalline material exhibiting a nematic phase is easily arranged regularly as compared with liquid crystalline materials exhibiting other liquid crystal phases.

  In this step, it is preferable to use a material having spacers at both ends of the mesogen as the liquid crystalline material exhibiting the nematic phase. Since the liquid crystalline material having spacers at both ends of the mesogen is excellent in flexibility, the retardation film produced by the production method of the present invention can be made excellent in transparency by using such a liquid crystalline material. is there.

  Furthermore, as the rod-shaped compound used in this step, those having a polymerizable functional group in the molecule are preferably used, and among them, those having a polymerizable functional group capable of three-dimensional crosslinking are more preferably used. Since the rod-shaped compound has a polymerizable functional group, the rod-shaped compound can be polymerized and fixed, so that a retardation layer having excellent alignment stability and hardly causing a change in retardation with time is obtained. Because you can. In addition, when the rod-shaped compound which has a polymerizable functional group is used, the phase difference layer formed by performing this process will contain the rod-shaped compound bridge | crosslinked by the polymerizable functional group.

  The “three-dimensional cross-linking” means that liquid crystal molecules are polymerized three-dimensionally to form a network (network) structure.

  Examples of the polymerizable functional group include polymerizable functional groups that are polymerized by the action of ionizing radiation such as ultraviolet rays and electron beams, or heat. Representative examples of these polymerizable functional groups include radically polymerizable functional groups or cationic polymerizable functional groups. Further, representative examples of radically polymerizable functional groups include functional groups having at least one addition-polymerizable ethylenically unsaturated double bond, and specific examples include vinyl groups having or not having substituents, An acrylate group (generic name including an acryloyl group, a methacryloyl group, an acryloyloxy group, and a methacryloyloxy group) and the like can be given. Moreover, an epoxy group etc. are mentioned as a specific example of the said cation polymerizable functional group. In addition, examples of the polymerizable functional group include an isocyanate group and an unsaturated triple bond. Among these, from the viewpoint of the process, a functional group having an ethylenically unsaturated double bond is preferably used.

Furthermore, the rod-like compound in this step is a liquid crystalline material exhibiting liquid crystallinity, and those having the polymerizable functional group at the terminal are particularly preferable. By using such a rod-like compound, for example, it can be polymerized three-dimensionally into a network (network) structure, so that it has column stability and excellent optical characteristics. This is because the above can be formed.
In this step, even when a liquid crystalline material having a polymerizable functional group at one end is used, the alignment can be stabilized by crosslinking with other molecules.

  Specific examples of the rod-like compound used in this step include compounds represented by the following formulas (1) to (17).

  In addition, in this process, only 1 type may be used for the said rod-shaped compound, or 2 or more types may be mixed and used for it. For example, when the rod-shaped compound is used by mixing a liquid crystalline material having one or more polymerizable functional groups at both ends and a liquid crystalline material having one or more polymerizable functional groups at one end, The polymerization density (crosslinking density) and the optical properties are preferably adjusted by adjusting the ratio. Further, from the viewpoint of ensuring reliability, a liquid crystalline material having one or more polymerizable functional groups at both ends is preferable, but from the viewpoint of liquid crystal alignment, it is preferable that there is one polymerizable functional group at both ends. .

  The content of the rod-shaped compound used in this step in the coating solution for forming the retardation layer is set to a desired value for the viscosity of the coating solution for forming the retardation layer depending on the coating method applied on the alignment layer. There is no particular limitation as long as it is possible. Especially in this process, it is preferable that it exists in the range of 5 mass%-30 mass% in the said coating liquid for phase difference layer formation, and it exists in the range of 10 mass%-20 mass% especially. Is preferred.

The retardation layer forming coating solution used in this step contains at least the rod-like compound, but usually contains a solvent. Moreover, you may contain another compound as needed.
Such a solvent is not particularly limited as long as it can uniformly dissolve or disperse the rod-like compound, but the same as described in the above section “A. Method for producing alignment film”. be able to.

The other compound is not particularly limited as long as it does not impair the arrangement order of the rod-like compound in the retardation layer formed by this step. As said other compound used for this process, a chiral agent, a polymerization initiator, a polymerization inhibitor, a plasticizer, surfactant, a silane coupling agent etc. can be mentioned, for example.
In this step, when the polymerizable liquid crystal material is used as the rod-shaped compound, it is preferable to use a polymerization initiator or a polymerization inhibitor as the other compound.

  Examples of the polymerization initiator include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamine) benzophenone, 4,4-bis (diethylamine) benzophenone, α-amino acetophenone, 4,4-dichloro. Benzophenone, 4-benzoyl-4-methyldiphenyl ketone, dibenzyl ketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p- tert-Butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyldimethyl ketal, benzylmethoxyethyl acetal, benzo Methyl ether, benzoin butyl ether, anthraquinone, 2-tert-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzsuberone, methyleneanthrone, 4-azidobenzylacetophenone, 2,6-bis (p- Azidobenzylidene) cyclohexane, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2-phenyl-1,2-butadion-2- (o-methoxycarbonyl) oxime, 1-phenyl-propanedione-2 -(O-ethoxycarbonyl) oxime, 1,3-diphenyl-propanetrione-2- (o-ethoxycarbonyl) oxime, 1-phenyl-3-ethoxy-propanetrione-2- (o-benzoyl) oxy , Michler's ketone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, naphthalene Sulfonyl chloride, quinoline sulfonyl chloride, n-phenylthioacridone, 4,4-azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylphosphine, camphorquinone, Adeka N1717, carbon tetrabromide, tri Examples include combinations of photoreducing dyes such as bromophenyl sulfone, benzoin peroxide, eosin, and methylene blue with reducing agents such as ascorbic acid and triethanolamine. In this step, these photopolymerization initiators can be used alone or in combination of two or more.

  Furthermore, when using the said photoinitiator, a photoinitiator adjuvant can be used together. Examples of such photopolymerization initiation assistants include tertiary amines such as triethanolamine and methyldiethanolamine, and benzoic acid derivatives such as ethyl 2-dimethylaminoethylbenzoate and ethyl 4-dimethylamidebenzoate. Yes, but not limited to these.

  Examples of the polymerization inhibitor include diphenylpicrylhydrazide, tri-p-nitrophenylmethyl, p-benzoquinone, p-tert-butylcatechol, picric acid, copper chloride, methylhydroquinone, methoquinone, tert-butylhydroquinone and the like. Although a polymerization inhibitor for the reaction can be used, a hydroquinone polymerization inhibitor is preferred from the viewpoint of storage stability, and methyl hydroquinone is particularly preferred.

  In addition, other compounds as shown below can be added to the retardation layer forming coating solution in this step. Other compounds that can be added include, for example, a polyester (meth) acrylate obtained by reacting a (meth) acrylic acid with a polyester prepolymer obtained by condensing a polyhydric alcohol with a monobasic acid or polybasic acid; a polyol Polyurethane (meth) acrylate obtained by reacting a group and a compound having two isocyanate groups with each other and then reacting the reaction product with (meth) acrylic acid; bisphenol A type epoxy resin, bisphenol F type epoxy resin , Epoxy resins such as novolac type epoxy resin, polycarboxylic acid polyglycidyl ester, polyol polyglycidyl ether, aliphatic or cycloaliphatic epoxy resin, amino group epoxy resin, triphenolmethane type epoxy resin, dihydroxybenzene type epoxy resin, ( Meta) Epoxy obtained by reacting acrylic acid (meth) photopolymerizable compound such as acrylate; photopolymerizable liquid crystal compound having an acryl group or methacryl group and the like.

  The coating method for the retardation layer forming coating liquid in this step is not particularly limited as long as it can stably form a coating film made of the retardation layer forming coating liquid on the alignment layer. . In this step, specifically, it can be the same as the method for forming the alignment layer forming layer described in the above section “A. Method for producing alignment film”.

  The thickness of the coating film formed in this step is not particularly limited as long as it is within the range in which a predetermined retardation can be achieved after the orientation step described later, and is manufactured by the manufacturing method of the present invention. It is appropriately determined depending on the use of the retardation film.

  In this step, when the in-plane retardation after the alignment step is set to a thickness within a range corresponding to λ / 4 minutes, the specific thickness depends on the type of rod-shaped compound. Will be decided. However, if the thickness is a rod-like compound that is generally used in this step, it is usually preferable that the thickness after the alignment step is in the range of 0.1 μm to 1.9 μm, and 0.25 μm. More preferably, it is within the range of ˜1.75 μm, and even more preferably within the range of 0.5 μm to 1.5 μm.

2. Alignment step The alignment step in the present invention is a step in which rod-like compounds contained in the coating film of the retardation layer forming coating liquid are arranged along the direction of the minute line-shaped uneven structure formed in the alignment layer. is there.

  The method for arranging the rod-shaped compound in this step along the direction of the fine line-shaped uneven structure formed in the alignment layer is not particularly limited as long as it can be arranged in a desired direction, Although a general method can be used, when the rod-shaped compound is a liquid crystalline material, a method of heating the coating film to a temperature higher than the liquid crystal phase forming temperature of the rod-shaped compound is used. Specifically, although it differs depending on the kind of the rod-like compound, a method of heating within a range of 50 ° C to 60 ° C can be mentioned.

The in-plane retardation value of the retardation layer formed by this step can be appropriately determined according to the use of the retardation film produced according to the present invention. Therefore, what is necessary is just to adjust suitably according to the use of the phase difference film manufactured by this invention.
In this step, in the case where the in-plane retardation value of the retardation layer corresponds to λ / 4 minutes, specifically, it is preferably in the range of 100 nm to 160 nm, More preferably within the range of 150 nm, even more preferably within the range of 120 nm to 140 nm.

Here, the in-plane retardation value is an index indicating the degree of birefringence in the in-plane direction of the refractive index anisotropic body. When the refractive index in the fast axis direction orthogonal to the slow axis direction is Ny and the thickness in the direction perpendicular to the in-plane direction of the refractive index anisotropic body is d,
Re [nm] = (Nx−Ny) × d [nm]
It is a value represented by. The in-plane retardation value (Re value) can be measured by, for example, KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd. by the parallel Nicol rotation method, and the in-plane retardation value of a minute region is AXOMETRICS (USA). Measurements can also be made using a Mueller matrix with an AxoScan made by the manufacturer. In the present specification, unless otherwise stated, the Re value means a value at a wavelength of 589 nm.

3. Method for producing retardation film The method for producing a retardation film of the present invention comprises at least the coating step and the orientation step. If necessary, after the coating step, a coating solution for forming a retardation layer is applied. When a polymerizable liquid crystal material is used as the drying step for drying the film or the rod-like compound, a polymerization step for polymerizing the polymerizable liquid crystal material may be included.

As a method for drying the coating film in the drying step, a commonly used drying method such as a heat drying method, a reduced pressure drying method, a gap drying method, or the like can be used. Further, the drying method in this step is not limited to a single method, and a plurality of drying methods may be employed, for example, by changing the drying method sequentially according to the amount of remaining solvent.
Furthermore, as a method for drying the coating film, a method of applying a drying air adjusted to a certain temperature to the coating film can be used. When using such a drying method, the method is applied to the coating film. The wind speed of the drying wind is preferably 3 m / second or less, and particularly preferably 30 m / minute or less.

  What is necessary is just to determine arbitrarily as a polymerization method of the polymeric liquid crystal material in the said superposition | polymerization process according to the kind of polymeric functional group which polymeric liquid crystal material has. In particular, in this step, a method of curing by irradiation with actinic radiation is preferable. The actinic radiation is not particularly limited as long as it is a radiation capable of polymerizing the polymerizable liquid crystal material, but it is usually preferable to use ultraviolet light or visible light from the viewpoint of the ease of the apparatus. .

Further, in the present invention, an adhesive layer forming step (FIGS. 10A to 10B) for forming the adhesive layer 6 on the retardation layer as illustrated in FIG. 10 and a separator laminating step for laminating the separator 7 ( 10 (b) to (c)) or after the orientation step, the long retardation film may be cut to have a cutting step for obtaining a retardation film formed on a sheet. .
Also, the reference numerals in FIG. 10 indicate the same members as those in FIG.

In the present invention, each of these steps is performed independently, that is, a long alignment film or the like is unwound in a roll shape for each step and wound after performing a predetermined treatment. Although it may be taken, it is preferable that all steps are performed continuously, that is, the raw material is rolled to roll.
Specifically, when the alignment film manufactured by the above-described method for manufacturing an alignment film is long, the phase difference film as the final product is wound up in a roll shape from the long alignment film. It is preferable to manufacture with a roll toe roll without being done.

4). Retardation Film Use of the retardation film produced according to the present invention includes viewing angle compensation, a three-dimensional display device used with a pattern retardation film having a first retardation region and a second retardation region, and the like. In particular, it is suitable for display devices that are easily affected by dust and static electricity and are required to be low in cost.

In addition, the aspect used for a three-dimensional display apparatus with a pattern phase difference film is demonstrated with reference to figures. FIG. 11 shows an example of a light-emitting display device that uses a combination of a pattern retardation film and a λ / 4 plate as a retardation film and can perform three-dimensional display by a passive method. The principle is as follows.
First, the pixel portion of the light-emitting display is divided into a plurality of two types of pixels, a right-eye video display pixel and a left-eye video display pixel, and a right-eye video is displayed on one group of pixels, The left eye image is displayed on the pixels of the group. Next, as the pattern retardation film, the first retardation region of the retardation layer is formed so as to correspond to the arrangement pattern of the left-eye image display pixels, and the region other than the first retardation region (in FIG. Nothing is formed in the area.) Is prepared so as to correspond to the arrangement pattern of the right-eye video display pixels. And the pattern phase difference film used for such this aspect is arrange | positioned at the display surface side of a polarizing plate, Furthermore, (lambda) / 4 board is arrange | positioned at the display surface side of a pattern phase difference film. At this time, the direction of the slow axis of the first retardation region and the direction of the polarization axis of the polarizing plate intersect at 45 °, and further, the slow axis direction of the first retardation region and the λ / 4 plate The slow axis direction should be parallel or orthogonal. By disposing the pattern retardation film and the λ / 4 plate in this manner, images displayed by the right-eye image display pixel and the left-eye image display pixel (hereinafter referred to as “right-eye image” and “left-eye image”, respectively) Is visually recognized by the observer through the following route.
That is, each image displayed by the right-eye image display pixel and the left-eye image display pixel first passes through the polarizing plate, and thus is converted into linearly polarized light. Here, in FIG. 11, since the polarization axis of the polarizing plate is in the 0 ° direction, each image transmitted through the second polarizing plate is also linearly polarized light in the 0 ° direction. Next, each image thus converted into linearly polarized light (0 °) is incident on the pattern retardation film used in this embodiment, but the left-eye image passes through the first retardation region, Since the image for the right eye passes through an area where no retardation layer is formed, the image for the left eye is transmitted through the pattern retardation film as linearly polarized light (L1) having a polarization axis of 90 °, but the image for the right eye is changed. No, the pattern retardation film is transmitted with the linearly polarized light (L2) having a polarization axis of 0 °. Next, when L1 and L2 are incident on the λ / 4 plate, the left-eye image is converted into right-handed circularly polarized light (C1), and the right-eye image is converted into left-handed circularly polarized light (C2). It will be.
As described above, the right-eye image and the left-eye image that have passed through the pattern retardation film and the λ / 4 plate are converted into circularly polarized light orthogonal to each other. By attaching circularly polarized glasses that use circularly polarized lenses orthogonal to each other, the right-eye image passes only through the right-eye lens, and the left-eye image passes only through the left-eye lens, The right-eye image can reach only the right eye, and the left-eye image can reach only the left eye, which enables three-dimensional display.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples.

[Example 1]

  A plate having a random minute line-shaped uneven structure made of a nickel substrate that was paper-polished in the direction of 45 ° with respect to the longitudinal direction of the substrate was prepared.

The dimensions of the concavo-convex structure of minute lines were height: 5 nm to 5 μm, width: 1 nm to 3 μm, and period (pitch): 0.5 nm to 3 μm.
In addition, about the width | variety of the fine line-shaped uneven structure, the height, and the period, the surface was observed using Hitachi High-Technologies scanning electron microscope S-4500. Moreover, the cross section was manufactured with the glass section | slice, the cross section of the said film was observed using the scanning electron microscope S-4500 made from Hitachi High-Technologies, and it measured from the obtained image.

[Evaluation]
(1) Preparation of alignment film The following method confirmed the formation property of the alignment film using the said original plate.
As a transparent film substrate, TAC (triacetylcellulose) of 60 μm was coated with an acrylic ultraviolet curable resin composition having a solid content of 100% and 200 mPa · s so as to have a thickness of 10 μm. After pressing with a load of / cm to fill the fine concavo-convex structure and pattern, the substrate was irradiated with ultraviolet rays, solidified and then peeled to obtain a substrate (alignment film) having an alignment layer.

  When the obtained alignment film was measured by measurement using the above-mentioned scanning electron microscope, it was confirmed that the pattern alignment film had a fine line-shaped uneven structure of 45 ° of the original.

  The reaction rate of the acrylic ultraviolet curable resin composition constituting the alignment layer was 70%.

  A solvent-dispersed UV curable liquid crystal having a solid content of 20% diluted with a diluent solvent in which MEK (methyl ethyl ketone) and MIBK (methyl isobutyl ketone) are mixed at a mass ratio of 4 to 1 is used as a diluent solvent on the alignment film. The film was coated to a thickness of 1 μm, and the solvent was dried and evaporated at 50 ° C. for 30 seconds, followed by UV curing to obtain a retardation film having a retardation layer (hereinafter sometimes referred to as a liquid crystal layer).

(Adhesion evaluation)
About the obtained retardation film, it performed according to the cross-cut test prescribed | regulated to JISK5600-5-6 (the test which makes a cut so that it may cross | cross in a 90 degree direction, and peels with a cellophane tape (made by Nichiban Co., Ltd.)). . Specifically, make a cut so that it crosses the liquid crystal surface vertically and horizontally at 90 °, and apply cellophane tape on it, peel it slowly at 90 °, and the retardation layer and alignment layer will remain without peeling off I confirmed. When 80% or more of the whole peeled, it was judged that there was no practicality.
As a result, it was confirmed that there was no peeling and sufficient adhesion was obtained.
(Phase difference evaluation)
As a result of visual confirmation using crossed Nicols, orientation at 45 ° was clearly confirmed.

[Example 2]
A plate having a random fine line-shaped uneven structure made of a crackless chrome substrate which was ground with a paper in a direction of 135 ° with respect to the longitudinal direction of the substrate was prepared.

[Evaluation]
(1) Preparation of alignment film After heating and melting a thermoplastic acrylic resin composition (viscosity 2 g / 10 min) to a temperature equal to or higher than the melting point, it is coated on a plate to a thickness of 100 μm by a T-die method, and 1500 MPa / It was pressed with a weight of cm, filled with a fine concavo-convex structure and a pattern, solidified and then peeled to obtain a substrate (alignment film) having an alignment layer.

  When the obtained alignment film was measured by the measurement using the above-mentioned scanning electron microscope, it was confirmed that it had a fine line-shaped uneven structure of 135 °.

  Moreover, the reaction rate of the thermoplastic acrylic resin composition which comprises the said orientation layer was 100%.

(2) Production of Retardation Film A retardation layer was formed in the same manner as in Example 1, and adhesion evaluation and retardation evaluation were performed.
As a result, it was confirmed that the adhesiveness was sufficient.
As for the orientation, the orientation at 135 ° was clearly confirmed.

[Example 3]
A plate having a random minute line-like uneven structure made of a DLC substrate that was paper-polished in the direction of 90 ° with respect to the longitudinal direction of the substrate was prepared.

[Evaluation]
(1) Preparation of alignment film 45% solid content diluted with a dilution solvent in which MEK and MIBK are mixed at a mass ratio of 4: 1 to 60 μm TAC as a transparent film substrate, 2500 mPa · s After coating the acrylic UV curable resin composition with a thickness of 8 μm and drying and evaporating the solvent at 80 ° C. for 30 seconds, it was pressed against the prepared plate with a rubber roll under a load of 1000 MPa / cm, and fine irregularities After filling the structure and pattern, the substrate was irradiated with ultraviolet rays, solidified and then peeled to obtain a substrate (alignment film) having an alignment layer.

  When the obtained alignment film was measured by the measurement using the above-mentioned scanning electron microscope, it was confirmed that it had a fine line-shaped uneven structure of 90 °.

  The reaction rate of the acrylic ultraviolet curable resin composition constituting the alignment layer was 45%.

(2) Production of Retardation Film A retardation layer was formed in the same manner as in Example 1, and adhesion evaluation and retardation evaluation were performed.
As a result, it was confirmed that the adhesiveness was sufficient.
As for the orientation, the orientation at 90 ° was clearly confirmed.

[Comparative example]
A plate made of a nickel substrate that was mirror-polished so that the surface roughness was 0.05 S was prepared.

  In addition, although the shape of the obtained original plate was measured in the same manner as in Example 1, the minute uneven structure could not be measured.

  As a transparent film substrate, TAC of 60 μm is coated with an acrylic ultraviolet curable resin composition having a solid content of 100% and 200 mPa · s so as to have a thickness of 10 μm. After pressing and filling the fine concavo-convex structure and pattern, the substrate was irradiated with ultraviolet rays, solidified and then peeled to obtain a base material (alignment film) having an alignment layer.

  About the obtained alignment film, when measured by the measurement using the above-mentioned scanning electron microscope, the minute uneven structure could not be measured.

  The reaction rate of the acrylic ultraviolet curable resin composition constituting the alignment layer was 70%.

(2) Production of Pattern Retardation Film A retardation layer was formed in the same manner as in Example 1, and adhesion evaluation and retardation evaluation were performed.
As a result, it was confirmed that the adhesiveness was sufficient.

  However, the orientation was not oriented, and it was confirmed that there was a problem in practicality.

DESCRIPTION OF SYMBOLS 1 ... Transparent film base material 2 '... Orientation layer formation layer 2 ... Orientation layer 3 ... Retardation layer 5 ... Antireflection layer or anti-glare layer 6 ... Adhesion layer 7 ... Separator 10 ... Master for orientation layer 20 ... Orientation film 30 ... Retardation film

Claims (10)

An alignment layer forming layer comprising a resin composition for forming an alignment layer is brought into contact with an alignment layer original plate on which fine line-shaped uneven structures are randomly formed in a substantially constant direction, and then pressed to form the alignment layer. A forming step of forming the shape of the original surface of the alignment layer into the working layer;
After the molding step, the method includes a curing step of curing the alignment layer forming layer and a peeling step of peeling the alignment layer forming layer from the alignment layer original plate. .   The method for producing an alignment film according to claim 1, wherein the alignment layer original plate is a roll plate.   The method for producing an alignment film according to claim 1, wherein the peeling step is performed after the curing step. The shaping step is
Coating the alignment layer forming resin composition on the alignment layer original plate, and forming the alignment layer forming layer; and
Arrangement treatment for disposing a transparent film substrate on the alignment layer forming layer;
The method for producing an alignment film according to any one of claims 1 to 3, wherein the pressure is applied after the step. The shaping step is
Applying the alignment layer forming resin composition on a transparent film substrate, forming an alignment layer forming layer, and forming an alignment layer forming layer.
A contact treatment in which the alignment layer forming layer is brought into contact with the alignment layer original plate; and
The method for producing an alignment film according to any one of claims 1 to 3, wherein the pressure is applied after the step. The shaping step is
A filling treatment for coating the alignment layer forming resin composition on the alignment layer original plate and forming the alignment layer forming layer;
The method for producing an alignment film according to any one of claims 1 to 3, wherein the pressure is applied after the step.   The method for manufacturing an alignment film according to any one of claims 1 to 6, wherein a height of the minute line-shaped uneven structure is in a range of 5 nm to 5 µm.   The viscosity of the alignment layer forming resin composition is in the range of 5 mPa · s to 200,000 mPa · s, and the alignment film according to any one of claims 1 to 7 is manufactured. Method.   The method for producing an alignment film according to any one of claims 1 to 8, wherein the alignment layer forming resin composition is an ionizing radiation curable resin composition. A retardation layer comprising a rod-shaped compound having refractive index anisotropy on an alignment layer included in the alignment film formed by the method for manufacturing an alignment film according to any one of claims 1 to 9. An application step of applying a forming coating liquid;
An alignment step in which the rod-shaped compound contained in the coating film of the retardation layer forming coating liquid is aligned along the direction of the minute line-shaped uneven structure formed in the alignment layer;
A method for producing a retardation film, comprising: