JP2020166154A - Film for transferring oriented liquid crystal compound layer, laminate for transferring oriented liquid crystal compound layer, method for manufacturing oriented liquid crystal compound layer laminate, and method for inspecting laminate for transferring oriented liquid crystal compound layer - Google Patents

Abstract

To provide: a film for transferring an oriented liquid crystal compound layer which enables an orientation state of a liquid crystal compound layer to be inspected while the liquid crystal compound layer is provided as a releasable film for transferring an oriented liquid crystal compound layer; a laminate for transferring an oriented liquid crystal compound layer; a method for inspecting the same; and a method for manufacturing an oriented liquid crystal compound layer laminate using the laminate for transferring the oriented liquid crystal compound layer.SOLUTION: A film for transferring an oriented liquid crystal compound layer, in which the film for transfer has a metal thin film layer layered on at least one surface of a base material film, and has a release surface opposite to a side where the base material film of the metal thin film layer is layered.SELECTED DRAWING: None

Description

The present invention relates to a transfer film for transferring an oriented liquid crystal compound layer. More specifically, when manufacturing a polarizing plate such as a circular polarizing plate or a retardation plate in which a retardation layer composed of an oriented liquid crystal compound layer is laminated, or when manufacturing a polarizing plate having a polarizing layer composed of an oriented liquid crystal compound layer. The present invention relates to a transfer film for transferring an oriented liquid crystal compound layer used in the above.

Conventionally, in an image display device, a circularly polarizing plate is arranged on the panel surface of the image display panel on the viewer side in order to reduce the reflection of external light. This circular polarizing plate is composed of a laminate of a linear polarizing plate and a retardation film such as λ / 4, and converts external light toward the panel surface of the image display panel into linearly polarized light by the linear polarizing plate, followed by λ /. It is converted to circularly polarized light by a retardation film of 4 mag. When the external light due to circularly polarized light is reflected on the surface of the image display panel, the rotation direction of the polarizing surface is reversed, and on the contrary, this reflected light is shielded by a linear polarizing plate by a retardation film such as λ / 4. Since it is converted to linearly polarized light in the direction of light and then shielded by a linear polarizing plate, emission to the outside is suppressed. As described above, as the circularly polarizing plate, one in which a retardation film such as λ / 4 is bonded to the polarizing plate is used.

As the retardation film, a single retardation film such as cyclic olefin (see Patent Document 1), polycarbonate (see Patent Document 2), and a stretched film of triacetyl cellulose (see Patent Document 3) is used. Further, as the retardation film, a retardation film of a laminate having a retardation layer made of a liquid crystal compound on a transparent film (see Patent Documents 4 and 5) is used. In the above, it is described that the liquid crystal compound may be transferred when the retardation layer made of the liquid crystal compound is provided.

Further, a method of producing a retardation film by transferring a retardation layer made of a liquid crystal compound to a transparent film is known in Patent Document 6 and the like. A method is also known in which a retardation layer made of a liquid crystal compound such as λ / 4 is provided on a transparent film by such a transfer method to form a λ / 4 film (see Patent Documents 7 and 8).

In these transfer methods, various base materials for transfer have been introduced, and among them, transparent resin films such as polyester, triacetyl cellulose, and cyclic polyolefin are often exemplified. Unstretched films such as triacetyl cellulose and cyclic polyolefin are preferable because they do not have birefringence and the state of the retardation layer can be inspected (evaluated) with the retardation layer provided on the film substrate. Not only are these films expensive, but they are also inferior in mechanical strength when the films are thinned, and are not always optimal.

On the other hand, the stretched film is superior in mechanical strength to the unstretched film and is preferable as a film base material for transfer, but there is a problem that the orientation direction of the transferred retardation layer does not become the design orientation direction and deviates from the orientation direction. It often happened. When a polarizing plate having a phase difference in the orientation direction deviating from such a design is used for a display, problems such as light leakage may occur. In particular, the biaxially stretched polyester film is relatively inexpensive, has excellent mechanical strength and heat resistance, and is highly preferable as a film base material for transfer in these respects, but in the polyester film, this orientation direction The problem of misalignment and the resulting light leakage was particularly noticeable.

Japanese Unexamined Patent Publication No. 2012-56222 Japanese Unexamined Patent Publication No. 2004-144943 Japanese Unexamined Patent Publication No. 2004-46166 Japanese Unexamined Patent Publication No. 2006-243653 Japanese Unexamined Patent Publication No. 2001-4837 Japanese Patent Application Laid-Open No. 4-57017 Japanese Unexamined Patent Publication No. 2014-071381 Japanese Unexamined Patent Publication No. 2017-146616

The present invention has been made against the background of the problems of the prior art. That is, an object of the present invention is an oriented liquid crystal compound capable of inspecting the oriented state of the liquid crystal compound layer even if the liquid crystal compound layer is left as a releasable film for transferring the oriented liquid crystal compound layer. It is an object of the present invention to provide a film for layer transfer, a laminate for alignment liquid crystal compound layer transfer, and an inspection method thereof. Further, the present invention provides a method for producing an oriented liquid crystal compound layer laminate using the oriented liquid crystal compound layer transfer laminate.

The present inventor has completed the present invention as a result of diligent studies to achieve such an object. Typical inventions are as follows.
Item 1.
A transfer film for transferring an oriented liquid crystal compound layer, wherein the transfer film has a metal thin film layer laminated on at least one surface of the base film, and the base film of the metal thin film layer is laminated. An oriented liquid crystal compound layer transfer film having a release surface on the side opposite to the vertical side.
Item 2.
Item 2. The film for transferring an oriented liquid crystal compound layer according to Item 1, wherein the base film is a biaxially stretched polyester film.
Item 3.
The film for transferring an oriented liquid crystal compound layer according to claim 1 or 2, wherein the surface roughness SRa of the release surface is 30 nm or less.
Item 4.
Item 6. The film for transferring an oriented liquid crystal compound layer according to any one of Items 1 to 3, wherein the metal thin film layer is a vapor-deposited layer of aluminum.
Item 5.
A laminate for transferring an oriented liquid crystal compound layer in which a base film, a metal thin film layer, and an oriented liquid crystal compound layer are laminated in this order.
Item 6.
In the step (A) of preparing the aligned liquid crystal compound layer transfer laminate in which the base film, the metal thin film layer, and the oriented liquid crystal compound layer are laminated in this order, the oriented liquid crystal compound layer surface of the oriented liquid crystal compound layer transfer laminate is prepared. A method for producing an oriented liquid crystal compound layer laminate, which comprises a step (B) of laminating on the surface of the object to be transferred and a step (C) of peeling off the film for transferring the oriented liquid crystal compound layer and transferring the oriented liquid crystal compound layer to the surface of the object. ..
Item 7.
A method for inspecting the orientation state of the alignment liquid crystal compound layer of the alignment liquid crystal compound layer transfer laminate in which the base film, the metal thin film layer, and the alignment liquid crystal compound layer are laminated in this order, for transfer of the alignment liquid crystal compound layer. A method for inspecting a laminated body for transferring an oriented liquid crystal compound layer, which comprises a step (a) of irradiating polarized light from the oriented liquid crystal compound layer side of the laminated body and a step (b) of receiving the reflected polarized light.

According to the present invention, as a releasable film for transferring an oriented liquid crystal compound layer, an oriented liquid crystal compound layer transfer film capable of inspecting the oriented state of the liquid crystal compound layer even if the liquid crystal compound layer is still provided. , Aligned liquid crystal compound layer transfer laminate and an inspection method thereof. Further, the oriented liquid crystal compound layer transfer laminate can be used to produce the oriented liquid crystal compound layer laminate.

The oriented liquid crystal compound layer transfer film of the present invention is a transfer film for transferring the oriented liquid crystal compound layer. The oriented liquid crystal compound layer transfer film has a metal thin film layer laminated on at least one surface of the base film, and has a release surface on the side opposite to the side on which the base film of the metal thin film layer is laminated. .. Further, the oriented liquid crystal compound layer which is a transfer material is provided on the metal thin film layer side. When inspecting the orientation state of the oriented liquid crystal compound layer by adopting such a configuration, the inventors irradiate light from the oriented liquid crystal compound layer surface, pass through the oriented liquid crystal compound layer, and then reflect it on the metal thin film layer. Furthermore, by inspecting the polarization state of the reflected light that has passed through the oriented liquid crystal compound layer, the oriented state of the oriented liquid crystal compound layer can be known, and in this case, the presence or absence of orientation and the orientation direction of the base film. We have found that the orientation state of the alignment liquid crystal compound layer can be inspected without being affected by the disturbance, and have reached the present invention. Hereinafter, the oriented liquid crystal compound layer transfer film may be simply referred to as a transfer film.

(Base film)
The resin of the base film is not particularly limited, and any resin film such as polyester, polycarbonate, polyamide, polyimide, polyamideimide, polystyrene, triacetyl cellulose, polypropylene, and cyclic polyolefin can be used without limitation. Among these, polyester is preferable from the viewpoint of mechanical strength, heat resistance, supply stability and the like, and polyethylene terephthalate is more preferable.

Polyethylene terephthalate may be copolymerized. Examples of the dicarboxylic acid component to be copolymerized include isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, cyclohexanedicarboxylic acid, adipic acid, and sebacic acid. Examples of the copolymerized cricol component include diethylene glycol, neopentyl glycol, trimethylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,6-hexanediol, cyclohexanedimethanol and the like. The amount of these copolymerization components is not limited as long as the physical properties of the film substrate for transfer of the oriented liquid crystal compound layer can be maintained, but when the dicarboxylic acid component and the diol component are each 100 mol%, it is preferably 30 mol% or less. , More preferably 20 mol% or less, still more preferably 10 mol% or less.

The lower limit of the thickness of the base film is preferably 1 μm, more preferably 5 μm, still more preferably 8 μm, and particularly preferably 10 μm. By making the above amount or more, the handleability is excellent, the elongation during the process is suppressed, and the oriented liquid crystal compound layer in the oriented state as designed can be transferred.
The upper limit of the thickness of the base film is preferably 100 μm, more preferably 70 μm, further preferably 60 μm, particularly preferably 50 μm, and most preferably 48 μm. By setting the above or less, the handleability, productivity, and cost can be reduced.

The lower limit of the elastic modulus of the base film in the film flow direction (MD direction) is preferably 1 GPa, more preferably 2 GPa. The lower limit of the elastic modulus in the direction perpendicular to the MD direction (TD direction) of the base film is preferably 1 GPa, more preferably 2 GPa. By setting the elastic modulus to the above or higher, the handleability is excellent, the elongation during the process is suppressed, and the oriented liquid crystal compound layer in the oriented state as designed can be transferred.

The upper limit of the elastic modulus of the base film in the MD direction is preferably 10 GPa, more preferably 8 GPa. The upper limit of the elastic modulus of the base film in the TD direction is preferably 10 GPa, more preferably 8 GPa. A film can be produced by a general method by making the above or less.

The lower limit of the heat shrinkage rate of the base film at 150 ° C. for 30 minutes is preferably -1%, more preferably 0%. The upper limit of the heat shrinkage rate at 150 ° C. for 30 minutes is preferably 5%, more preferably 4%, further preferably 3%, particularly preferably 2%, and most preferably 1.5%. Within the above range, deformation of the film during heating in each step such as drying and orientation treatment of the liquid crystal compound layer can be suppressed, and the oriented liquid crystal compound layer in the oriented state as designed can be transferred.
The heat shrinkage rate is preferably in the above range in all directions of 0 degrees, 45 degrees, 90 degrees, and 135 degrees with respect to the MD direction.

The upper limit of the maximum heat shrinkage rate of the base film at 95 ° C. for 30 minutes is preferably 2.5%, more preferably 2%, further preferably 1.2%, and particularly preferably 1%. , Most preferably 0.8%. The lower limit of the maximum heat shrinkage rate at 95 ° C. of the base film is preferably 0.01%. By setting the content within the above range, deformation of the film during heating in each step such as drying and alignment treatment of the liquid crystal compound layer can be suppressed, and the oriented liquid crystal compound layer in the oriented state as designed can be transferred.

(Composition of base film)

The configuration may be a single layer or a plurality of coextruded layers. In the case of a plurality of layers, the surface layer (layer A of the laminated surface with the metal thin film layer) / back surface layer (B), A / B / A (the layer of the laminated surface with the metal thin film layer and the back surface layer are the same), A / Examples thereof include an intermediate layer (C) / B and the like.

The base film may be an unstretched film or a stretched film, but is preferably a stretched film in terms of high elastic modulus and heat resistance and high productivity.

In the case of a heat-meltable resin such as polyester or cyclic polyolefin, the unstretched film can be obtained by extruding the molten resin onto a cooling roll in the form of a sheet. Further, a material that is easily thermally decomposed, such as triacetyl cellulose, can be obtained by pouring a dope dissolved in a solvent onto a metal belt or the like and removing the solvent.

In the case of a stretched film, it can be obtained by stretching the unstretched film obtained by increasing the draft ratio when extruding into a sheet shape into a cooling roll shape.

Stretching may be uniaxial stretching, weak biaxial stretching (stretching in the biaxial direction but weak in one direction), or biaxial stretching, but the characteristics are equal in the MD direction and the TD direction. Therefore, biaxial stretching is preferable.
In the case of biaxial stretching, simultaneous biaxial stretching or sequential biaxial stretching may be used. Stretching in the longitudinal direction is preferably stretched by roll groups having different speed differences, and stretching in the lateral direction and simultaneous biaxial stretching is preferably tenter stretching.

The film for transferring the oriented liquid crystal compound layer is industrially supplied by a roll around which the film is wound. The lower limit of the roll width is preferably 30 cm, more preferably 50 cm, still more preferably 70 cm, particularly preferably 90 cm, and most preferably 100 cm.
The upper limit of the roll width is preferably 5000 cm, more preferably 4000 cm, and even more preferably 3000 cm.
The film length is preferably 500 m or more, more preferably 1000 m or more. The length of the film is preferably 30,000 m or less, more preferably 20,000 m or less.

(Surface treatment of base film)
In order to improve the adhesion of the base film to the metal thin film layer and the flattening coat layer described later, surface treatment such as corona treatment, plasma treatment, and flame treatment may be performed.

An easy-adhesion coat layer may be provided on the base film. The easy-adhesive coating layer can be provided by applying a coating liquid composition in which a resin is dissolved in a solvent to a base film and drying it. The coating on the base film may be either an in-line coating performed in the film forming process of the film or an offline coating performed once the film is wound and then coated on the film.

Examples of the resin used for the easy-adhesion coating layer include polyester, polyurethane, acrylic, polycarbonate, polyamide, polystyrene, and epoxy resin, which are appropriately selected depending on the resin of the base film and the type of metal of the thin film layer.

It is preferable to use a cross-linking agent for the easy-adhesion coating layer. Examples of the cross-linking agent include isocyanate compounds, melamine compounds, epoxy resins, and oxazoline compounds.

The lower limit of the thickness of the easy-adhesion coat layer is preferably 0.001 μm, more preferably 0.005 μm, and even more preferably 0.01 μm. The upper limit of the thickness of the easy-adhesion coat layer is preferably 2 μm, more preferably 1 μm, still more preferably 0.5 μm, and particularly preferably 0.3 μm.

(Flattening coat)
The interface of the base film with the metal thin film layer is preferably flat. If the surface roughness of the base film after film formation is large, flattening coating can be performed. Examples of the resin used for the flattening coat include those generally used as a resin for a coating agent such as polyester, acrylic, polyurethane, polystyrene, and polyamide. It is also preferable to use a cross-linking agent such as a melamine, an isocyanate compound, an epoxy resin, or an oxazoline compound. These are applied and dried as a coating agent dissolved or dispersed in an organic solvent or water. Alternatively, in the case of acrylic, it may be coated without a solvent and cured by radiation.
In the present invention, the easily adhesive coating layer and the flattening coating layer may also be referred to as a base film.

(Metal thin film layer)
A metal thin film layer is laminated on the base film. The metal used for the metal thin film layer is not particularly limited, and examples thereof include gold, silver, copper, aluminum, nickel, titanium, tin, indium, and alloys thereof. Of these, aluminum is preferable in terms of price and ease of thin film formation.

As a method for laminating the metal thin film layer, there are a dry process and a method of laminating metal foils, but the dry process is preferable. Examples of the dry process include vacuum deposition, sputtering, and a CVD method, and vacuum deposition is preferable in terms of productivity.

The lower limit of the thickness of the metal thin film layer is preferably 0.001 μm, more preferably 0.005 μm, still more preferably 0.01 μm, and particularly preferably 0.03 μm. With the above setting or more, the reflectance required for inspecting the orientation state of the liquid crystal compound can be obtained.
The upper limit of the thickness of the metal thin film layer is preferably 10 μm, more preferably 5 μm, further preferably 3 μm, particularly preferably 2 μm, and most preferably 1 μm. Even if it exceeds the above, the reflectance is about the same, and in the case of the dry process, it takes time to form a film and the productivity may be inferior.

(Surface treatment of metal thin film layer)
The metal thin film layer may be subjected to surface treatment such as oxidation treatment and nitriding treatment. Further, the metal thin film layer may be surface-treated in order to improve the adhesion with the release layer. Examples of the surface treatment include treatment with a coupling agent such as titanium and silicon, and resin coating with polyester, polyurethane, acrylic, polycarbonate, polyamide, polystyrene, epoxy resin and the like.

(Release layer)
As the metal thin film layer, an orientation liquid crystal compound layer or an orientation control layer, which is a transfer product, may be provided directly on the metal thin film layer. Further, a release layer may be further provided on the surface of the metal thin film layer.

Examples of the release layer include alkyd resin, amino resin, olefin resin, long-chain acrylate copolymer acrylic resin, silicone resin, silicone-modified acrylic resin, and fluororesin.

The lower limit of the thickness of the release layer is preferably 0.01 μm, more preferably 0.05 μm, still more preferably 0.07 μm, and particularly preferably 0.1 μm. The upper limit of the thickness of the release layer is preferably 10 μm, more preferably 7 μm, still more preferably 5 μm, and particularly preferably 3 μm. Within the above range, the required releasability can be ensured, and high productivity and low cost can be achieved.

The preferable thickness of the surface-treated coat layer is the same as the range of the easy-adhesion coat layer described above.

(Surface roughness of mold release surface)
In the present invention, the release surface is preferably smooth. If the surface roughness of the release surface is large, the orientation control layer of the convex portion will be peeled off during rubbing if it is an orientation control layer, and the rubbing of the foot of the convex portion and the concave portion will be insufficient, and the orientation of the alignment liquid crystal compound layer will be insufficient. Is disturbed, which may cause defects.
Further, regardless of whether it is a rubbing orientation control layer or a photoalignment control layer, when it is wound with the orientation control layer provided, it rubs against the back surface layer, so that a hole is formed in the orientation control layer of the convex portion. It is conceivable that the orientation is disturbed by the pressure. It is considered that the defect of these orientation control layers is caused by the fact that the orientation of the liquid crystal compound does not occur in a minute portion when the liquid crystal compound orientation is provided on the orientation control layer.

In the present invention, the release surface is a surface on which an orientation liquid crystal compound layer (orientation control layer when an orientation control layer is provided) is provided.

The lower limit of the release surface roughness SRa is preferably 1 nm, more preferably 1.5 nm, and even more preferably 2.0 nm. The upper limit of the roughness SRa of the release surface is preferably 30 nm, more preferably 25 nm, further preferably 20 nm, particularly preferably 15 nm, and most preferably 10 nm.

The lower limit of the ten-point average surface roughness SRz of the release surface is preferably 5 nm, more preferably 10 nm, and further preferably 13 nm. The upper limit of the ten-point average surface roughness SRz of the release surface is preferably 200 nm, more preferably 150 nm, further preferably 120 nm, particularly preferably 100 nm, and most preferably 80 nm.

The lower limit of the maximum height SRy of the release surface (maximum release surface height SRp + maximum release surface valley depth SRv) is preferably 10 nm, more preferably 15 nm, and even more preferably 20 nm. The upper limit of the maximum height SRy of the release surface is preferably 300 nm, more preferably 250 nm, further preferably 150 nm, particularly preferably 120 nm, and most preferably 100 nm.

The upper limit of the number of protrusions of 0.5 μm or more on the release surface is preferably 5 / m ² , more preferably 4 / m ² , still more preferably 3 / m ² , and particularly preferably 2. a number / ^{m 2,} most preferably a 1 / ^{m 2.}

Within the above range, defects (pinhole-like defects) in a minute region of the oriented liquid crystal compound layer can be reduced by a general smoothing method.

The roughness of the release surface is the roughness of the release surface before the rubbing process is performed when the release surface is directly subjected to the rubbing process.

(How to smooth the release surface)
In order to keep the release surface within the above range, it is preferable to first reduce the surface roughness of the surface of the base film on which the metal thin film layer is provided. The method for that is as follows.
-The release surface side layer of the base film shall not contain particles.
-If the release surface side layer of the base film contains particles, use particles with a small particle size.
-If the surface roughness of the release surface side layer of the base film is large because it contains particles, a flattening coat is provided.
In the present invention, the "release surface side layer" of the base film refers to the layer on the side where the release surface exists among the layers of the resin constituting the base film (among the layers of the base film). It means the layer closest to the release surface). Here, even when the base film is a single layer, it may be referred to as a release surface side layer. When the base film is a single layer, the back surface side layer and the release surface side layer, which will be described later, are the same layer.

In addition to the above, it is also important to clean the raw materials and manufacturing process as follows.
-Use a raw material resin that does not contain foreign matter or coarse particles.
-Clean the environment from the loading of the raw material resin to the loading of the film-forming machine.-During film-forming, the molten resin is filtered to remove aggregated particles and foreign substances.
-Filter the coating agent to remove foreign matter.
・ Perform in a clean environment during film formation, coating, and drying.

It is preferable that the release surface side layer is substantially free of particles for smoothing. Substantially particle-free is less than 50 ppm and less than 30 ppm.

On the other hand, in order to increase the slipperiness of the base film, particles may be contained. When particles are included, the lower limit of the particle content is preferably 50 ppm, more preferably 100 ppm. The upper limit of the particle content of the release surface side layer is preferably 20000 ppm, more preferably 10000 ppm, still more preferably 8000 ppm, and particularly preferably 6000 ppm. If it exceeds the above, the surface roughness may not be within the preferable range.

The lower limit of the particle size of the release surface side layer is preferably 0.005 μm, more preferably 0.01 μm, and further preferably 0.02 μm. The upper limit of the particle size of the release surface side layer is preferably 3 μm, more preferably 1 μm, still more preferably 0.5 μm, and particularly preferably 0.3 μm. If it exceeds the above, the roughness of the release surface side layer may not be within a preferable range.

When the release surface side layer does not contain particles or even if the particles have a small particle size but the lower layer contains particles, the roughness of the release surface side layer becomes high due to the influence of the particles in the lower layer. There is. In such a case, it is preferable to take a method such as increasing the thickness of the release surface side layer or providing a lower layer (intermediate layer) containing no particles.

The lower limit of the thickness of the release surface side layer is preferably 0.1 μm, more preferably 0.5 μm, further preferably 1 μm, particularly preferably 3 μm, and most preferably 5 μm. The upper limit of the thickness of the release surface side layer is preferably 97%, more preferably 95%, still more preferably 90% with respect to the total thickness of the base film.

The particle-free intermediate layer preferably contains less than 50 ppm, more preferably less than 30 ppm, in the sense that it is substantially free of particles. The lower limit of the thickness of the intermediate layer is preferably 10%, more preferably 20%, still more preferably 30% with respect to the total thickness of the base film. The upper limit is preferably 95%, more preferably 90%.

The surface roughness of the base film on the metal thin film layer laminated side is the same as the preferable range of the surface roughness of the release surface for SRa, SRz, and SRy. Further, the number of protrusions of 0.5 μm or more is the same as the preferable range of the release surface.

(Surface roughness of metal thin film layer)
The surface roughness of the metal thin film layer is preferably small. Polarized ultraviolet rays may be irradiated when aligning the liquid crystal compound, but if the surface roughness is large, the amount of polarized ultraviolet rays diffusely reflected on the metal surface may increase, and the oriented state as set may not be obtained.
As for the surface roughness of the metal thin film layer, SRa, SRz, and SRy are the same as the preferable range of the surface roughness of the release surface. Further, the number of protrusions of 0.5 μm or more is the same as the preferable range of the release surface.
When the metal thin film layer is carried out by a dry process, the surface roughness of the base film is basically reflected. Therefore, the method for reducing the surface roughness of the metal thin film layer is as described above.
In a process such as thin film deposition, when a splash (metal bumping) occurs, the droplets may adhere to the metal thin film layer and a partial convex portion may be formed. It is preferable to control the vapor deposition process so that splash does not occur.

(Surface roughness of release layer)
When the release layer is provided on the metal thin film layer, the surface roughness of the release layer can be made equal to or less than the surface roughness of the metal thin film layer. In this case, the release layer should not contain particles, if it contains particles, it should be fine particles, the coating liquid of the release layer should be filtered to remove agglomerated particles and foreign substances, coating, and drying. Sometimes it is preferable to take a method such as performing in a clean environment.

(Glossiness of film for transfer of oriented liquid crystal compound layer)
The oriented liquid crystal compound layer transfer film of the present invention preferably has a high glossiness when measured from the release surface side. The lower limit of glossiness is preferably 200%, more preferably 300%, still more preferably 400%, and particularly preferably 450%. Most preferably it is 500%. By setting the glossiness to the above level or higher, an orientation state as set can be obtained when the liquid crystal compound is oriented by polarized ultraviolet rays. In addition, accuracy can be ensured when inspecting the orientation state of the alignment liquid crystal compound layer.

The glossiness is a value measured based on the mirror glossiness measurement method of JIS Z8741 (1997) with a reflectance of 10% as a glossiness of 100 (%) at an incident angle of 60 ° on a glass surface having a refractive index of 1.567. Is.

The glossiness can be increased by reducing the surface roughness of the metal thin film layer and, when providing a release layer, by using a highly transparent release layer.

(Roughness on the back side)
Further, even if the release surface is smoothed, a defect may occur in the oriented liquid crystal compound layer, which constitutes the surface opposite to the release surface of the transfer film (hereinafter referred to as the back surface, and also constitutes the base film). It was found that, among the layers, the layer having the back surface is referred to as the back surface layer) to have a specific roughness.
It was found that this is because the oriented liquid crystal compound layer transfer film is wound in a roll shape and the front surface and the back surface are in contact with each other, so that the roughness of the back surface is transferred to the front surface. In the oriented liquid crystal compound layer transfer film before coating with the oriented liquid crystal compound layer, the convex portion on the back surface is transferred to the release layer to form a concave portion. When the metal thin film layer is a release surface, pinholes may be formed in the metal thin film layer due to the convex portion on the back surface.
Further, the oriented liquid crystal compound layer transfer film provided with the oriented liquid crystal compound layer may be wound by laminating a masking film in order to protect the oriented liquid crystal compound layer, but it is wound as it is for cost reduction. Often. In this case, it is considered that when the orientation control layer is wound with the orientation control layer provided, the orientation control layer is dented, has holes, or the orientation of the orientation control layer is disturbed due to the convex portion on the back surface. Further, after the oriented liquid crystal compound layer is provided, it is considered that a phenomenon that a hole is formed in the oriented liquid crystal compound layer and the orientation is disturbed due to the convex portion on the back surface occurs. In particular, the pressure is high in the core portion, and these phenomena are likely to occur.

The lower limit of the average roughness SRa of the center surface of the back surface is preferably 2 nm, more preferably 3 nm, still more preferably 4 nm, and particularly preferably 5 nm. If it is less than the above, the slipperiness is deteriorated, and it may not slip smoothly during roll transportation, winding, etc., and may be easily scratched.
The upper limit of the average roughness SRa of the central surface of the back surface is preferably 50 nm, more preferably 45 nm, and further preferably 40 nm. Beyond the above, there may be many drawbacks.

The lower limit of the ten-point average surface roughness SRz on the back surface is preferably 7 nm, more preferably 10 nm, further preferably 15 nm, particularly preferably 20 nm, and most preferably 25 nm.
The upper limit of the ten-point average surface roughness SRz on the back surface is preferably 1500 nm, more preferably 1200 nm, further preferably 1000 nm, particularly preferably 700 nm, and most preferably 500 nm. Beyond the above, there may be many drawbacks.

The lower limit of the maximum height SRy on the back surface (maximum mountain height SRp on the back surface + maximum valley depth SRv on the back surface) is preferably 15 nm, more preferably 20 nm, still more preferably 25 nm, particularly preferably 30 nm, and most. It is preferably 40 nm. The upper limit of the maximum height SRy of the back surface is preferably 2000 nm, more preferably 1500 nm, further preferably 1200 nm, particularly preferably 1000 nm, and most preferably 700 nm. Beyond the above, there may be many drawbacks.

The upper limit of the number of protrusions of 2 μm or more is preferably 5 pieces / m ² , more preferably 4 pieces / m ² , further preferably 3 pieces / m ² , and particularly preferably 2 pieces / m ² . , Most preferably 1 piece / m ² . Beyond the above, there may be many drawbacks.

In order to cover the back surface in the above range, when the base film is a stretched film, the following method can be mentioned.
-The back layer of the base film should contain specific particles.
-Use a film containing particles in the intermediate layer of the base film, and reduce the thickness by assuming that the back layer does not contain particles.
-If the back surface layer of the base film has a large roughness, provide a flattening coat.
-If the back layer of the base film does not contain particles, provide an easy-slip coat.

The lower limit of the particle size of the particles contained in the back surface layer is preferably 0.01 μm, more preferably 0.05 μm, and even more preferably 0.1 μm. If it is less than the above, the slipperiness is deteriorated and winding failure may occur.
The upper limit of the particle size of the particles contained in the back surface layer is preferably 5 μm, more preferably 3 μm, and even more preferably 2 μm. If it exceeds the above, the back surface may become too rough.

When the back surface layer contains particles, the lower limit of the particle content is preferably 50 ppm, more preferably 100 ppm. If it is less than the above, the slippery effect of adding particles may not be obtained.
The upper limit of the particle content of the back surface layer is preferably 10000 ppm, more preferably 7000 ppm, and even more preferably 5000 ppm. If it exceeds the above, the back surface may become too rough.

The lower limit of the thickness of the back surface layer is preferably 0.1 μm, more preferably 0.5 μm, further preferably 1 μm, particularly preferably 3 μm, and most preferably 5 μm. The upper limit of the thickness of the back surface layer is preferably 95%, more preferably 90%, still more preferably 85% with respect to the total thickness of the base film.

It is also preferable to control the roughness of the back surface by including particles in the intermediate layer and thinning the back surface layer without containing particles. By taking such a form, it is possible to secure the roughness of the back surface while preventing the particles from falling off.
The particle size and the amount of particles added in the intermediate layer are the same as those in the back surface layer. In this case, the lower limit of the thickness of the back surface layer is preferably 0.5 μm, more preferably 1 μm, and even more preferably 2 μm. The upper limit of the thickness is preferably 30 μm, more preferably 25 μm, and even more preferably 20 μm.

When the back surface of the base film is rough, it is also preferable to provide a flattening coat layer on the back surface. As the flattening coat layer, those mentioned in the surface flattening coat can be used in the same manner.
The lower limit of the thickness of the back surface flattening coat layer is preferably 0.01 μm, more preferably 0.03 μm, and even more preferably 0.05 μm. If it is less than the above, the effect of flattening may be reduced.
The upper limit of the thickness of the back surface flattening coat layer is preferably 10 μm, more preferably 5 μm, and even more preferably 3 μm. Even if it exceeds the above, the flattening effect is saturated.

The back surface layer of the base film may not contain particles, and an easy-slip coat containing particles may be provided on the back surface.
The lower limit of the particle size of the particles contained in the back surface slippery coat layer is preferably 0.01 μm, more preferably 0.05 μm. If it is less than the above, slipperiness may not be obtained.
The upper limit of the particle size of the particles contained in the back surface slippery coat layer is preferably 5 μm, more preferably 3 μm, further preferably 2 μm, and particularly preferably 1 μm. If it exceeds the above, the roughness of the back surface may be too high.

The lower limit of the particle content of the back surface slippery coat layer is preferably 0.1% by mass, more preferably 0.5% by mass, still more preferably 1% by mass, and particularly preferably 1.5% by mass. It is most preferably 2% by mass. If it is less than the above, slipperiness may not be obtained.
The upper limit of the particle content of the back surface slippery coat layer is preferably 20% by mass, more preferably 15% by mass, and further preferably 10% by mass. If it exceeds the above, the roughness of the back surface may be too high.

The lower limit of the back surface slippery coat layer thickness is preferably 0.01 μm, more preferably 0.03 μm, and even more preferably 0.05 μm.
The upper limit of the thickness of the back surface slippery coat layer is preferably 10 μm, more preferably 5 μm, further preferably 3 μm, particularly preferably 2 μm, and most preferably 1 μm.

Although the case of a stretched film has been described above, even in the case of a film forming method by a casting method in which a dope dissolved in a solvent such as triacetyl cellulose is developed on a metal belt or the like and the solvent is dried, it is coarsened by adding particles. The solvent can be adjusted. As the solvent is removed, unevenness due to particles occurs on the upper surface (opposite surface of the metal belt). In this case, it is preferable to reduce the surface roughness of the metal belt and use the metal belt surface as the release surface. In addition, when the dope contains particles, if it is peeled off from the metal belt while the solvent content is high, unevenness due to the particles may appear on the metal belt surface. Therefore, after drying to a state where the solvent content is low, the metal belt It is also preferable to peel off. Roughness can also be adjusted at the timing of these peelings. Further, when stretching and drying in the tenter with a small amount of solvent contained, the roughness can be adjusted by the stretching ratio or the like. Further, when particles are not contained, the roughness of the metal belt may be adjusted so that the metal belt surface is the back surface. Further, the roughness may be transferred to the surface while being dried while being passed between rolls having different roughness.

Even when a molten resin such as COP is cast and used as an unstretched film, adding particles is a preferable method for adjusting the roughness. By using particles such as inorganic particles having a coefficient of thermal expansion different from that of the base film resin, unevenness due to the added particles can be formed on the surface by heat shrinkage that occurs during cooling. In this case, it is preferable to reduce the surface roughness of the cooling roll that extrudes the molten resin into a sheet to form a release surface. Further, the cooling roll may be roughened to transfer the roughness, and the back surface may be used. Roughness may be transferred between rolls having different roughness at a temperature of Tg or more of the film resin.

The roughness of these unstretched films can also be adjusted by a smooth coating or an easy-slip coating containing particles.

(Laminate for transfer of oriented liquid crystal compound layer)
Next, the laminated body for transferring the oriented liquid crystal compound layer of the present invention will be described. Hereinafter, for the sake of simplicity, the laminated body for transferring the oriented liquid crystal compound layer may be referred to as the laminated body for transfer.
The laminated body for transferring the oriented liquid crystal compound layer of the present invention has a structure in which the oriented liquid crystal compound layer and the film for transferring the oriented liquid crystal compound layer of the present invention are laminated. The oriented liquid crystal compound layer is provided on the side opposite to the base film of the metal thin film layer (metal thin film layer side).
The oriented liquid crystal compound layer needs to be coated and oriented on the oriented liquid crystal compound layer transfer film. Orientation methods include a method of imparting an orientation control function by rubbing the lower layer (the release surface of the transfer film) of the alignment liquid crystal compound layer, or a method of directly irradiating the liquid crystal with polarized ultraviolet rays after applying the liquid crystal compound. There is a way to orient the compound.

(Orientation control layer)
Further, a method in which an orientation control layer is provided on the transfer film and an orientation liquid crystal compound layer is provided on the orientation control layer is also preferable. In the present invention, the alignment liquid crystal compound layer may be collectively referred to as the alignment control layer and the alignment liquid crystal compound layer as a general term, instead of the alignment liquid crystal compound layer alone. The orientation control layer may be any orientation control layer as long as a layer such as a liquid crystal compound provided on the orientation control layer can be brought into a desired orientation state, but a resin coating film is rubbed. Preferable examples include a treated rubbing treatment orientation control layer and a photoalignment control layer that orients molecules by irradiation with polarized light to generate an orientation function.

(Rubbing treatment orientation control layer)
As the polymer material used for the orientation control layer formed by the rubbing treatment, polyvinyl alcohol and its derivative, polyimide and its derivative, acrylic resin, polysiloxane derivative and the like are preferably used.

Hereinafter, a method for forming the rubbing treatment orientation control layer will be described. First, the rubbing treatment orientation control layer coating liquid containing the above polymer material is applied onto the release surface of the transfer film, and then heat-dried to obtain an orientation control layer before the rubbing treatment. The orientation control layer coating liquid may have a cross-linking agent.

The solvent for the rubbing treatment orientation control layer coating liquid can be used without limitation as long as it dissolves the polymer material. Specific examples include alcohols such as water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol and cellosolve; ester solvents such as ethyl acetate, butyl acetate and gamma butyrolactone; acetone, methyl ethyl ketone, cyclopentanone and cyclohexanone. , Etc.; aromatic hydrocarbon solvents such as toluene or xylene; and ether solvents such as tetrahydrofuran or dimethoxyethane. These solvents may be used alone or in combination.

The concentration of the rubbing treatment orientation control layer coating liquid can be appropriately adjusted depending on the type of polymer and the thickness of the orientation control layer to be produced, but it is preferably 0.2 to 20% by mass in terms of solid content concentration. The range of 0.3 to 10% by mass is particularly preferable. As the coating method, a known method such as a coating method such as a gravure coating method, a die coating method, a bar coating method and an applicator method, or a printing method such as a flexographic method is adopted.

The heat-drying temperature depends on the transfer film, but when the base film is PET, it is preferably in the range of 30 ° C. to 170 ° C., more preferably 50 to 150 ° C., and even more preferably 70 to 130 ° C. When the drying temperature is low, it is necessary to take a long drying time, which may result in inferior productivity. If the drying temperature is too high, the transfer film may be stretched by heat, the heat shrinkage may be large, the optical function as designed may not be achieved, or the flatness may be deteriorated. The heating and drying time may be, for example, 0.5 to 30 minutes, more preferably 1 to 20 minutes, and even more preferably 2 to 10 minutes.

The thickness of the rubbing treatment orientation control layer is preferably 0.01 to 10 μm, more preferably 0.05 to 5 μm, and particularly preferably 0.1 μm to 1 μm.

Next, a rubbing process is performed. The rubbing treatment can generally be carried out by rubbing the surface of the polymer layer with paper or cloth in a certain direction. Generally, the surface of the orientation control layer is rubbed using a rubbing roller of a brushed cloth made of fibers such as nylon, polyester, and acrylic. In order to provide the oriented liquid crystal compound layer that is oriented in a predetermined direction diagonally with respect to the longitudinal direction of the elongated film, it is necessary to set the rubbing direction of the orientation control layer at an angle corresponding to it. The angle can be adjusted by adjusting the angle between the rubbing roller and the transfer film, and adjusting the transfer speed of the transfer film and the rotation speed of the roller.

It is also possible to directly apply a rubbing treatment to the release surface of the transfer film to give the transfer film surface an orientation control function, which is also included in the technical scope of the present invention.

(Photo-orientation control layer)
The photo-orientation control layer is an orientation in which an orientation regulating force is imparted by applying a coating liquid containing a polymer or monomer having a photoreactive group and a solvent to a transfer film and irradiating the transfer film with polarized light, preferably polarized ultraviolet rays. It refers to a film. The photoreactive group is a group that produces a liquid crystal alignment ability by irradiation with light. Specifically, it produces a photoreaction that is the origin of the liquid crystal orientation ability, such as a molecule orientation-inducing or isomerization reaction, a dimerization reaction, a photocrosslinking reaction, or a photodecomposition reaction that occurs when light is irradiated. is there. Among the photoreactive groups, those that cause a dimerization reaction or a photocrosslinking reaction are preferable in that they have excellent orientation and maintain the liquid crystal state of the retardation layer and the polarizing film. The photoreactive group capable of causing the above reaction is preferably an unsaturated bond, particularly a double bond, and is a group consisting of a C = C bond, a C = N bond, an N = N bond, and a C = O bond. Groups having at least one selected from the above are particularly preferred.

Examples of the photoreactive group having a C = C bond include a vinyl group, a polyene group, a stillben group, a stillbasol group, a stillbasolium group, a chalcone group and a cinnamoyl group. Examples of the photoreactive group having a C = N bond include a group having a structure such as an aromatic Schiff base and an aromatic hydrazone. Examples of the photoreactive group having an N = N bond include an azobenzene group, an azonaphthalene group, an aromatic heterocyclic azo group, a bisazo group, a formazan group, and the like, and those having an azoxybenzene as a basic structure. Examples of the photoreactive group having a C = O bond include a benzophenone group, a coumarin group, an anthraquinone group and a maleimide group. These groups may have substituents such as an alkyl group, an alkoxy group, an allyl group, an allyloxy group, a cyano group, an alkoxycarbonyl group, a hydroxyl group, a sulfonic acid group and an alkyl halide group.

Among them, a photoreactive group capable of causing a photodimerization reaction is preferable, and a photo-alignment layer in which a cinnamoyl group and a chalcone group require a relatively small amount of polarized light for photo-orientation and are excellent in thermal stability and temporal stability. It is preferable because it is easy to obtain. Furthermore, as the polymer having a photoreactive group, a polymer having a cinnamoyl group such that the terminal portion of the side chain of the polymer has a cinnamic acid structure is particularly preferable. Examples of the structure of the main chain include polyimide, polyamide, (meth) acrylic, polyester, and the like.

Specific examples of the orientation control layer include JP-A-2006-285197, JP-A-2007-76839, JP-A-2007-138138, JP-A-2007-94071, and JP-A-2007-121721. , JP-A-2007-140465, JP-A-2007-156439, JP-A-2007-133184, JP-A-2009-109831, JP-A-2002-229039, JP-A-2002-265541, Orientation described in Kai 2002-317013, Japanese Patent Application Laid-Open No. 2003-520878, Japanese Patent Application Laid-Open No. 2004-522220, Japanese Patent Application Laid-Open No. 2013-33248, Japanese Patent Application Laid-Open No. 2015-7702, Japanese Patent Application Laid-Open No. 2015-129210. A control layer can be mentioned.

As the solvent of the coating liquid for forming the photoalignment control layer, any solvent can be used as long as it dissolves a polymer and a monomer having a photoreactive group. As a specific example, the one mentioned in the method of forming the rubbing treatment orientation control layer can be exemplified. It is also preferable to add a photopolymerization initiator, a polymerization inhibitor, and various stabilizers to the coating liquid for forming the photoalignment control layer. Further, a polymer other than the polymer having a photoreactive group and the monomer, or a monomer having no photoreactive group copolymerizable with the monomer having a photoreactive group may be added.

The concentration, coating method, and drying conditions of the coating liquid for forming the photo-orientation control layer can also be exemplified by those mentioned in the method for forming the rubbing treatment orientation control layer. The thickness is also the same as the preferable thickness of the rubbing treatment orientation control layer.

Polarized light is applied from the direction of the photo-alignment control layer surface before orientation.
The wavelength of polarized light is preferably in the wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb light energy. Specifically, ultraviolet rays having a wavelength in the range of 250 to 400 nm are preferable. Examples of the polarized light source include xenon lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, metal halide lamps, ultraviolet light lasers such as KrF and ArF, and high-pressure mercury lamps, ultra-high pressure mercury lamps, and metal halide lamps are preferable. ..

Polarization is obtained, for example, by passing light from the light source through a polarizer. The direction of polarization can be adjusted by adjusting the polarization angle of the polarizer. Examples of the polarizer include a polarizing filter, a polarizing prism such as a Gran Thomson or a Granter, and a wire grid type polarizer. The polarized light is preferably substantially parallel light.

By adjusting the angle of the polarized light to be irradiated, the direction of the orientation regulating force of the optical orientation control layer can be arbitrarily adjusted.

The irradiation intensity varies depending on the type and amount of the polymerization initiator and the resin (monomer), but for example, it is preferably 10 to 10000 mJ / cm ^{2 based on} 365 nm, and more preferably ²⁰ to 5000 mJ / cm ² .

(Oriented liquid crystal compound layer)
The oriented liquid crystal compound layer is not particularly limited as long as the liquid crystal compound is oriented. Specific examples include a polarizing film (polarizer) containing a liquid crystal compound and a dichroic dye, and a retardation layer containing a rod-shaped or discotic liquid crystal compound.

(Polarizing film)
The polarizing film has a function of passing polarized light in only one direction and contains a dichroic dye.

(Dichroic pigment)
The dichroic dye refers to a dye having a property in which the absorbance in the major axis direction and the absorbance in the minor axis direction of the molecule are different.

The dichroic dye preferably has an absorption maximum wavelength (λMAX) in the range of 300 to 700 nm. Examples of such a dichroic dye include an acrydin dye, an oxazine dye, a cyanine dye, a naphthalene dye, an azo dye and an anthraquinone dye, and among them, the azo dye is preferable. Examples of the azo dye include a monoazo dye, a bisazo dye, a trisazo dye, a tetrakisazo dye and a stilbene azo dye, and preferably a bisazo dye and a trisazo dye. The dichroic dyes may be used alone or in combination, but it is preferable to combine two or more kinds in order to adjust the color tone (achromatic color). In particular, it is preferable to combine three or more types. In particular, it is preferable to combine three or more kinds of azo compounds.

Preferred azo compounds include dyes described in JP-A-2007-126628, JP-A-2010-168570, JP-A-2013-101328, and JP-A-2013-210624.

The dichroic dye is also preferably a dichroic dye polymer introduced into the side chain of a polymer such as acrylic. Examples of these dichroic dye polymers include polymers listed in JP-A-2016-4055 and polymers obtained by polymerizing compounds [Chemical formula 6] to [Chemical formula 12] in JP-A-2014-206682.

The content of the dichroic dye in the polarizing film is preferably 0.1 to 30% by mass, more preferably 0.5 to 20% by mass in the polarizing film from the viewpoint of improving the orientation of the dichroic dye. , 1.0 to 15% by mass is more preferable, and 2.0 to 10% by mass is particularly preferable.

It is preferable that the polarizing film further contains a polymerizable liquid crystal compound in order to improve the film strength, the degree of polarization, and the film homogeneity. Here, the polymerizable liquid crystal compound also includes a film after polymerization.

(Polymerizable liquid crystal compound)
The polymerizable liquid crystal compound is a compound having a polymerizable group and exhibiting liquid crystallinity.
The polymerizable group means a group involved in the polymerization reaction, and is preferably a photopolymerizable group. Here, the photopolymerizable group refers to a group that can undergo a polymerization reaction with an active radical, an acid, or the like generated from a photopolymerization initiator described later. Examples of the polymerizable group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an oxylanyl group, an oxetanyl group and the like. Of these, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxylanyl group and an oxetanyl group are preferable, and an acryloyloxy group is more preferable. The liquid crystal compound may be a thermotropic liquid crystal or a riotropic liquid crystal, and may be a nematic liquid crystal or a smectic liquid crystal in the thermotropic liquid crystal.

As the polymerizable liquid crystal compound, a smectic liquid crystal compound is preferable in that higher polarization characteristics can be obtained, and a higher-order smectic liquid crystal compound is more preferable. When the liquid crystal phase formed by the polymerizable liquid crystal compound is a higher-order smectic phase, a polarizing film having a higher degree of orientation order can be produced.

Specific preferred polymerizable liquid crystal compounds include, for example, JP-A-2002-308832, JP-A-2007-16207, JP-A-2015-163596, JP-A-2007-510946, JP-A-2013-114131. No., WO2005 / 045485, Lub et al. Recl. Trav. Chim. Examples thereof include those described in Pays-Bas, 115, 321-328 (1996) and the like.

The content ratio of the polymerizable liquid crystal compound in the polarizing film is preferably 70 to 99.5% by mass, more preferably 75 to 99% by mass, and further, from the viewpoint of increasing the orientation of the polymerizable liquid crystal compound. It is preferably 80 to 97% by mass, and particularly preferably 83 to 95% by mass.

The polarizing film can be provided by applying a polarizing film composition paint. The polarizing film composition coating material may contain a solvent, a polymerization initiator, a sensitizer, a polymerization inhibitor, a leveling agent, a polymerizable non-liquid crystal compound, a cross-linking agent and the like.

As the solvent, those listed as the solvent of the alignment layer coating liquid are preferably used.

The polymerization initiator is not limited as long as it polymerizes a polymerizable liquid crystal compound, but a photopolymerization initiator that generates active radicals by light is preferable. Examples of the polymerization initiator include benzoin compounds, benzophenone compounds, alkylphenone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts and sulfonium salts.

The sensitizer is preferably a photosensitizer, and examples thereof include xanthone compounds, anthracene compounds, phenothiazines, and rubrene.

Examples of the polymerization inhibitor include hydroquinones, catechols, and thiophenols.

The polymerizable non-liquid crystal compound is preferably one that copolymerizes with the polymerizable liquid crystal compound, and examples thereof include (meth) crates when the polymerizable liquid crystal compound has a (meth) acryloyloxy group. The (meth) clearates may be monofunctional or polyfunctional. By using polyfunctional (meth) acrylates, the strength of the polarizing film can be improved. When a polymerizable non-liquid crystal compound is used, it is preferably 1 to 15% by mass, more preferably 2 to 10% by mass, and particularly preferably 3 to 7% by mass in the polarizing film. If it exceeds 15% by mass, the degree of polarization may decrease.

Examples of the cross-linking agent include a polymerizable liquid crystal compound and a compound capable of reacting with a functional group of a polymerizable non-liquid crystal compound, and examples thereof include an isocyanate compound, a melamine, an epoxy resin and an oxazoline compound.

A polarizing film composition A polarizing film is provided by applying a coating film directly on a transfer film or an orientation control layer, and then drying, heating, and curing as necessary.

As the coating method, as the coating method, a known method such as a coating method such as a gravure coating method, a die coating method, a bar coating method and an applicator method, or a printing method such as a flexographic method is adopted.

The transfer film after coating is guided to a warm air dryer, an infrared dryer, or the like, and is dried at 30 to 170 ° C., more preferably 50 to 150 ° C., still more preferably 70 to 130 ° C. The drying time is preferably 0.5 to 30 minutes, more preferably 1 to 20 minutes, and even more preferably 2 to 10 minutes.

Heating can be performed to more strongly orient the dichroic dye and the polymerizable liquid crystal compound in the polarizing film. The heating temperature is preferably in the temperature range in which the polymerizable liquid crystal compound forms a liquid crystal phase.

When the polarizing film composition coating material contains a polymerizable liquid crystal compound, it is preferably cured. Examples of the curing method include heating and light irradiation, and light irradiation is preferable. By curing, the dichroic dye can be fixed in an oriented state. The curing is preferably carried out in a state where the polymerizable liquid crystal compound has a liquid crystal phase formed therein, and may be cured by irradiating light at a temperature indicating the liquid crystal phase. Examples of the light in the light irradiation include visible light, ultraviolet light and laser light. Ultraviolet light is preferable because it is easy to handle.

The irradiation intensity is different in kind and amount of a polymerization initiator or a resin (monomer), for example, preferably 100~10000mJ / cm ² at 365nm reference, more preferably 200~5000mJ / cm ^2.

By applying the polarizing film composition coating film on the alignment control layer, the polarizing film is oriented along the orientation direction of the alignment layer, and as a result, the polarizing film has a polarization extinguishing axis in a predetermined direction. When the transfer film is directly coated without providing the control layer, the polarizing film can be oriented by irradiating the polarizing film with polarized light to cure the polarizing film forming composition. After that, it is preferable to heat-treat the dichroic dye firmly along the orientation direction of the polymer liquid crystal.

The thickness of the polarizing film is 0.1 to 5 μm, preferably 0.3 to 3 μm, and more preferably 0.5 to 2 μm.

(Phase difference layer)
Typical examples of the retardation layer are those provided for optical compensation between the polarizer of the liquid crystal display device and the liquid crystal cell, and λ / 4 layer and λ / 2 layer of a circular polarizing plate. As the liquid crystal compound, a rod-shaped liquid crystal compound, a discotic liquid crystal compound, or the like can be used depending on the purpose, such as a raw or negative A plate, a positive or negative C plate, or an O plate.

When used as optical compensation for a liquid crystal display device, the degree of phase difference is appropriately set depending on the type of the liquid crystal cell and the properties of the liquid crystal compound used in the cell. For example, in the case of the TN method, an O plate using a discotic liquid crystal is preferably used. In the case of the VA method or the IPS method, a C plate or an A plate using a rod-shaped liquid crystal compound or a discotic liquid crystal compound is preferably used. Further, in the case of the λ / 4 retardation layer and the λ / 2 retardation layer of the circularly polarizing plate, it is preferably used to form an A plate by using a rod-shaped compound. These retardation layers may be used not only as a single layer but also as a plurality of layers in combination.

The liquid crystal compound used for these retardation layers is preferably a polymerizable liquid crystal compound having a polymerizable group such as a double bond in terms of being able to fix the orientation state.

Examples of the rod-shaped liquid crystal compound include JP-A-2002-030042, JP-A-2004-204190, JP-A-2005-263789, JP-A-2007-119415, JP-A-2007-186430, and special publications. Examples thereof include rod-shaped liquid crystal compounds having a polymerizable group described in Kaihei 11-513360.
Specific compounds include
CH ₂ = CHCOO- (CH ₂ ) _m- O-Ph1-COO-Ph2-OCO-Ph1-O- (CH ₂ ) _n -OCO-CH = CH ₂
CH ₂ = CHCOO- (CH ₂ ) _m- O-Ph1-COO-NPh-OCO-Ph1-O- (CH ₂ ) _n -OCO-CH = CH ₂
CH ₂ = CHCOO- (CH ₂ ) _m- O-P1h-COO-Ph2-OCH ₃
CH ₂ = CHCOO- (CH ₂ ) _m- O-Ph1-COO-Ph1-Ph1-CH ₂ CH (CH ₃ ) C ₂ H ₅
In the formula, m and n are integers of 2 to 6 and
Ph1 and Ph2 are 1,4-phenyl groups (Ph2 may have a methyl group at the 2-position).
NPh is a 2,6-naphthyl group.
These rod-shaped liquid crystal compounds are commercially available from BASF as LC242 and the like, and they can be used.

A plurality of these rod-shaped liquid crystal compounds may be used in combination at any ratio.

Examples of the discotic liquid crystal compound include a benzene derivative, a tolucene derivative, a cyclohexane derivative, an azacrown-based compound, a phenylacetylene-based macrocycle, and the like, and various ones are described in JP-A-2001-155866. Is preferably used.
Among them, as the discotic compound, a compound having a triphenylene ring represented by the following general formula (1) is preferably used.

In the formula, R1 to R6 are independently represented by hydrogen, halogen, alkyl group, or -OX (where X is an alkyl group, an acyl group, an alkoxybenzyl group, or an epoxy-modified alkoxybenzyl group. Group, acryloyloxy-modified alkoxybenzyl group, acryloyloxy-modified alkyl group). R1 to R6 are preferably acryloyloxy-modified alkoxybenzyl groups represented by the following general formula (2) (where m is 4 to 10).

The retardation layer can be provided by applying a composition coating material for a retardation layer. The composition coating material for a retardation layer may contain a solvent, a polymerization initiator, a sensitizer, a polymerization inhibitor, a leveling agent, a polymerizable non-liquid crystal compound, a cross-linking agent and the like. As these, the ones described in the orientation control layer and the polarizing film can be used.

A retardation layer is provided by applying a composition coating material for a retardation layer onto a release surface or an orientation control layer of a transfer film, and then drying, heating, and curing.

As for these conditions, the conditions described in the orientation control layer and the polarizing film are preferably used.

A plurality of retardation layers may be provided. In this case, a plurality of retardation layers may be provided on one transfer film and transferred to an object, and a single retardation layer may be provided on one transfer film. A plurality of types of films provided with the retardation layer may be prepared and transferred to an object in order.

Further, the polarizing film and the retardation layer may be provided on one transfer film and transferred to an object. Further, a protective layer may be provided between the polarizer and the retardation layer, or a protective layer may be provided on the retardation layer or between the retardation layers. These protective layers may also be provided on the transfer film together with the retardation layer and the polarizing film to transfer to the object.

Examples of the protective layer include a transparent resin coating layer. The transparent resin is not particularly limited to polyvinyl alcohol, ethylene vinyl alcohol copolymer, polyester, polyurethane, polyamide, polystyrene, acrylic resin, epoxy resin and the like. A cross-linking agent may be added to these resins to form a cross-linked structure. Further, a photocurable composition such as acrylic such as a hard coat may be cured. Further, after the protective layer is provided on the transfer film, the protective layer may be subjected to a rubbing treatment, and the alignment liquid crystal compound layer may be provided on the protective layer without providing the orientation control layer.

(Manufacturing method of oriented liquid crystal compound layer laminate)
Next, a method for producing the oriented liquid crystal compound layer laminate of the present invention will be described.
The oriented liquid crystal compound layer laminate includes a polarizing plate having the aligned liquid crystal compound layer as a polarizer, a retardation plate having the aligned liquid crystal compound layer as a retardation layer, and a retardation layer laminated polarized light having the oriented liquid crystal compound layer as a retardation layer. Examples include boards. Further, the polarized light of the liquid crystal compound layer directly oriented on the image display cell such as the liquid crystal cell or the organic EL cell, the image display panel in which the polarizer or the retardation layer of the liquid crystal compound layer is bonded, the cover sheet on the surface, the cover case, etc. Those provided with children and retardation layers are also included.

The method for producing an oriented liquid crystal compound layer laminate of the present invention is a step of adhering the oriented liquid crystal compound layer surface of the oriented liquid crystal compound layer transfer laminate of the present invention to the surface of a transfer target to form an intermediate laminate, and an intermediate. The step of peeling the transfer film from the laminate and transferring the oriented liquid crystal compound layer to the surface of the object is included. The object to be transferred is a protective film or the like in the case of the above-mentioned polarizing plate or retardation plate, a polarizing plate in the case of a retardation layer laminated polarizing plate, an image display cell, a surface cover sheet, a cover case, or the like. ..

Hereinafter, a case where the oriented liquid crystal compound layer is an oriented liquid crystal compound layer used for a circularly polarizing plate will be described as an example. In the case of a circularly polarizing plate, a λ / 4 retardation layer is used as the retardation layer (referred to as an oriented liquid crystal compound layer in the transfer laminate). The front retardation of the λ / 4 retardation layer is preferably 100 to 180 nm. More preferably, it is 120 to 150 nm. When only the λ / 4 retardation layer is used as the circularly polarizing plate, the orientation axis (slow phase axis) of the λ / 4 retardation layer and the transmission axis of the polarizer are preferably 35 to 55 degrees, more preferably 40 to 50 degrees. Degrees, more preferably 42-48 degrees. When used in combination with the polarizer of a stretched film of polyvinyl alcohol, the absorption axis of the polarizer is generally in the length direction of the long polarizer film, so λ / for a long transfer film. When the four retardation layers are provided, it is preferable to orient the liquid crystal compound so as to be within the above range with respect to the length direction of the long transfer film. When the angle of the transmission axis of the polarizer is different from the above, the liquid crystal compound is oriented so as to have the above relationship in consideration of the angle of the transmission axis of the polarizer.

A circular polarizing plate is created by transferring the λ / 4 retardation layer in the transfer laminate in which the λ / 4 retardation layer and the transfer film are laminated to a polarizing plate. Specifically, the polarizing plate and the λ / 4 retardation layer surface of the transfer laminate are laminated to form an intermediate laminate, and the transfer film is peeled from the intermediate laminate. The polarizing plate may be one in which protective films are provided on both sides of the polarizer, but one in which protective films are provided on only one side is preferable. In the case of a polarizing plate in which a protective film is provided on only one side, it is preferable to attach a retardation layer to a surface (polarizer surface) opposite to the surface on which the polarizing element protective film is laminated. If protective films are provided on both sides, it is preferable that the retardation layer is attached to the intended surface on the image cell side. The surface assumed on the image cell side is a surface that is generally provided on the viewing side, such as a low reflection layer, an antireflection layer, and an antiglare layer, and is not surface-processed. The protective film on the side to which the retardation layer is bonded is preferably a protective film made of TAC, acrylic, COP or the like and having no retardation.

As the polarizer, a polarizer created by stretching a PVA-based film alone, or a polarizer created by applying PVA to an unstretched base material such as polyester or polypropylene and stretching the entire base material to protect the polarizer. Examples thereof include those transferred to a film and those in which a polarizer composed of a liquid crystal compound and a dichroic dye is coated or transferred to a polarizer protective film, and all of them are preferably used.

As a method of pasting, conventionally known ones such as an adhesive and an adhesive can be used. As the adhesive, a polyvinyl alcohol-based adhesive, an ultraviolet curable adhesive such as acrylic or epoxy, and a thermosetting adhesive such as epoxy or isocyanate (urethane) are preferably used. Examples of the adhesive include acrylic, urethane, and rubber adhesives. It is also preferable to use an optical transparent adhesive sheet without an acrylic base material.

When a transfer type polarizing element is used, the polarizer is transferred onto the retardation layer (aligned liquid crystal compound layer) of the transfer laminate, and then the polarizer and the retardation layer are subjected to an object (polarizer protective film). May be transferred to.

As the polarizer protective film on the side opposite to the side where the retarder retardation layer is provided, generally known ones such as TAC, acrylic, COP, polycarbonate, and polyester can be used. Of these, TAC, acrylic, COP, and polyester are preferable. Polyethylene terephthalate is preferable as the polyester. In the case of polyester, it is preferable that the in-plane retardation is 100 nm or less, particularly 50 nm or less, or a high retardation film of 3000 nm to 30,000 nm.

When using a polyester high retardation film, the angle between the transmission axis of the polarizer and the slow axis of the polyester film is 30 to 60 degrees for the purpose of preventing blackout and coloring when viewing the image with polarized sunglasses. The range is preferred, more preferably the range of 35-55 degrees. In order to reduce rainbow spots when observed from a shallow oblique direction with the naked eye, the angle between the transmission axis of the polarizer and the slow axis of the polyester film should be 10 degrees or less, or even 7 degrees or less. Alternatively, it is preferably 80 to 100 degrees, more preferably 83 to 97 degrees.

The polarizer protective film on the side opposite to the side where the retarder retardation layer is provided may be provided with an antiglare layer, an antireflection layer, a low reflection layer, a hard coat layer, and the like.

(Composite retardation layer)
The λ / 4 retardation layer alone may cause coloring over a wide range of the visible light region without becoming λ / 4. Therefore, the λ / 4 retardation layer may be used in combination with the λ / 2 retardation layer. The front retardation of the λ / 2 retardation layer is preferably 200 to 360 nm. More preferably, it is 240 to 300 nm.

In this case, it is preferable that the λ / 4 retardation layer and the λ / 2 retardation layer are arranged at an angle such that the total becomes λ / 4. Specifically, the angle (θ) between the orientation axis (slow axis) of the λ / 2 retardation layer and the transmission axis of the polarizer is preferably 5 to 20 degrees, more preferably 7 to 17 degrees. The angle between the orientation axis (slow phase axis) of the λ / 2 retardation layer and the orientation axis (slow phase axis) of λ / 4 is preferably in the range of 2θ + 45 degrees ± 10 degrees, more preferably 2θ + 45 degrees ± 5 degrees. It is a range, more preferably a range of 2θ + 45 degrees ± 3 degrees.

Also in this case, when used in combination with the polarizer of the stretched film of polyvinyl alcohol, the absorption axis of the polarizer is generally in the length direction of the long polarizing film, so that it is used for long transfer. When a λ / 2 retardation layer or a λ / 4 retardation layer is provided on the film, the liquid crystal compound is oriented so as to be within the above range with respect to the length direction or the vertical direction of the length of the long transfer film. Is preferable. When the angle of the transmission axis of the polarizer is different from the above, the liquid crystal compound is oriented so as to have the above relationship in consideration of the angle of the transmission axis of the polarizer.

As examples of these methods and retardation layers, JP-A-2008-149757, JP-A-2002-303722, WO2006 / 100830, JP-A-2015-64418 and the like can be referred to. ..

Further, it is also a preferable form to provide a C plate layer on the λ / 4 retardation layer in order to reduce a change in coloring when viewed from an angle. As the C plate layer, a positive or negative C plate layer is used according to the characteristics of the λ / 4 retardation layer and the λ / 2 retardation layer.

As a method of laminating these, for example, if it is a combination of a λ / 4 retardation layer and a λ / 2 retardation layer,
-A λ / 2 retardation layer is provided on the polarizer by transfer, and a λ / 4 retardation layer is further provided on the polarizer by transfer.
A λ / 4 retardation layer and a λ / 2 retardation layer are provided in this order on the transfer film, and these are transferred onto the polarizer.
A λ / 4 retardation layer, a λ / 2 retardation layer, and a polarizing film are provided in this order on the transfer film, and these are transferred to the object.
-A λ / 2 retardation layer and a polarizing film are provided on the transfer film in this order, and this is transferred to an object, and a λ / 4 retardation layer is further transferred onto this.
Various methods such as can be adopted.

Further, when laminating C plates, a method of transferring the C plate layer on the λ / 4 retardation layer provided on the polarizer, or providing a C plate layer on the transfer film and further λ on the C plate layer. Various methods such as a method of providing a / 4 retardation layer or a λ / 2 retardation layer and a λ / 4 retardation layer and transferring them can be adopted.

The thickness of the circularly polarizing plate thus obtained is preferably 120 μm or less. It is more preferably 100 μm or less, further 90 μm or less, particularly 80 μm or less, and most preferably 70 μm or less.

(Inspection of orientation state of oriented liquid crystal compound layer)
The oriented liquid crystal compound layer transfer film (that is, the aligned liquid crystal compound layer transfer laminate) in which the oriented liquid crystal compound layer is laminated has the optical characteristics for the aligned liquid crystal compound layer transfer even if the oriented liquid crystal compound layer is a retardation layer. It can be inspected in a state of being laminated on a film. The light for performing the inspection is emitted from the surface side of the oriented liquid crystal compound layer. The light that has passed through the oriented liquid crystal compound layer is reflected by the metal thin film layer, and the reflected light passes through the oriented liquid crystal compound layer again. By inspecting the polarization state of the reflected light, the orientation state of the oriented liquid crystal compound layer can be known. In this case, the orientation state of the alignment liquid crystal compound layer can be inspected without being affected by the presence or absence of orientation of the base film, the orientation direction, and the disorder thereof.

(Inspection of retardation layer)
In order to inspect the optical state of the retardation layer (aligned liquid crystal compound layer), the light source used for the inspection and the laminated body for transfer of the alignment liquid crystal compound layer to be inspected (the alignment liquid crystal compound layer is the retardation layer). A polarizing filter is provided between them to irradiate linearly polarized light from the oriented liquid crystal compound layer side, and the reflected light is received by a receiver installed on the oriented liquid crystal compound layer side to detect the polarized state. Further details will be described as an example.

Normally, the λ / 4 retardation layer used for circular polarization or the like is oriented diagonally with respect to the flow direction of the base film, so that linearly polarized light is parallel or perpendicular to the flow direction of the base film. It is preferable to irradiate. Parallel to the flow direction of the base film is preferably -10 to +10 degrees, more preferably -7 to 7 degrees, further preferably -5 to 5 degrees, particularly preferably -3 to 3 degrees, and most preferably. -2 to 2 degrees. Perpendicular to the flow direction of the base film is preferably 80 to 100 degrees, more preferably 83 to 97 degrees, further preferably 85 to 95 degrees, particularly preferably 87 to 93 degrees, and most preferably 88 to 92 degrees. Is. Since a polarizing element obtained by stretching polyvinyl alcohol, which is usually used, has a transmission axis perpendicular to the flow direction, if it exceeds the above range, the difference from the actual state becomes large, and accurate evaluation may not be possible.

It is preferable to provide a polarizing filter also between the light receiver and the laminated body for transferring the oriented liquid crystal compound layer to be inspected (the oriented liquid crystal compound layer is a retardation layer). For example, when the oriented liquid crystal compound layer is a combination of a λ / 4 retardation layer or a λ / 4 retardation layer and a λ / 2 retardation layer, the linearly polarized light is circularly polarized, and the liquid crystal is as designed. If the compound layer is oriented, the reflected light is linearly polarized light. By installing a polarizing filter at an angle that does not allow light in the vibration direction of this linearly polarized light to pass through, if the retardation layer is as set, the light detected by the receiver is quenching, but light. If there is a leak, it can be seen that the retardation layer is out of design.

The polarizing filter between the light source used for the inspection and the laminated body for transferring the oriented liquid crystal compound layer and the polarizing filter between the receiver and the laminated body for transferring the oriented liquid crystal compound layer may be the same. For example, a large polarizing filter that covers the width of the film to be inspected may be used, and the light source and the light receiver may be installed on the side opposite to the alignment liquid crystal compound layer transfer laminate of the polarizing filter.

When the oriented liquid crystal compound layer is an optical compensation layer used for a liquid crystal display, the oriented liquid crystal compound layer transfer laminate (the oriented liquid crystal compound layer is a retardation layer) and the light emitting side polarizing filter or the light receiving side polarizing filter. Between, or both, a retardation plate for converting the reflected light in the polarized state changed by the retardation layer of the laminated liquid crystal compound layer transfer to linearly polarized light when it is in the state as designed. It is preferable to provide it.
In this case as well, if the retardation layer is as set, the light detected by the receiver is quenching, but if there is light leakage, the retardation layer is out of design. You can see that.

In addition, install multiple types of receivers with slightly different angles of the polarizing filter and the angle and phase difference of the retardation plate, and detect in which direction and how much the phase difference and orientation direction of the retardation layer are deviated. You can also.

(Inspection of polarizing film)
When the oriented liquid crystal compound layer is a polarizing film, the polarizing film can be inspected by irradiating natural light (unpolarized light) and receiving the reflected light through a polarizing filter.
Further, the inspection can be performed by irradiating the oriented liquid crystal compound layer transfer film on which the polarizing film is laminated with light linearly polarized through a polarizing filter and receiving the reflected light.
In these cases, the polarizing filter is set at an angle that quenches the polarizing film provided on the alignment liquid crystal compound layer transfer film when it is as designed.

It is also possible to install a plurality of types of receivers having slightly different angles of the polarizing filters and detect in which direction and how much the orientation direction is deviated.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples, and may be carried out with appropriate modifications to the extent that it can be adapted to the gist of the present invention. It is possible, and they are all within the technical scope of the invention.
The evaluation method of physical properties in the examples is as follows.

(1) Heat shrinkage rate of the base film in the MD direction, TD direction, 45 degree direction, and 135 degree direction at 150 ° C. Measured according to JIS C 2318-1997 5.3.4 (dimension change). The film is cut into a width of 10 mm and a length of 250 mm in the direction to be measured, marked at intervals of 200 mm, and the interval (A) of the marks is measured under a constant tension of 5 gf. Then 15 films
After placing in an oven in an atmosphere of 0 ° C and heat-treating at 150 ± 3 ° C for 30 minutes under no load,
The mark interval (B) is measured under a constant tension of 5 gf. The heat shrinkage rate was calculated from the following formula.
Heat shrinkage rate (%) = (AB) / A × 100

(2) Maximum heat shrinkage rate of the base film at 95 ° C.
The polyester film cut out from each cutout portion of the slit roll was cut out into a square shape having a side of 21 cm, and left to stand in an atmosphere of 23 ° C. and 65% RH for 2 hours or more. A circle with a diameter of 80 mm centered on the center of the polyester film was drawn, and the diameter was measured at 5 degree intervals using a two-dimensional image measuring machine (QUICK IMAGE manufactured by MITUTOYO) with the flow direction of the film as 0 degree. Here, the film flow direction was set to 0 degrees, and clockwise (clockwise) was set as a positive angle and counterclockwise (counterclockwise) was set as a negative angle on the upper surface of the film. Since the diameter was measured, it was measured in all directions with measurements in the range of -90 degrees to 85 degrees. Next, this polyester film was heat-treated in warm water at 95 ° C. for 30 minutes, and then left to stand in an atmosphere of 23 ° C. and 65% RH for 2 hours or more. Then, the diameter of the circle was measured at 5 degree intervals in the same manner as described above. Let Lo be the diameter before the heat treatment and L be the diameter in the same direction after the heat treatment. The heat shrinkage rate in each direction is calculated according to the following formula, and the maximum value among the heat shrinkage rates in all directions is the maximum heat shrinkage rate. And said.
Heat shrinkage rate (%) = ((L0-L) / L0) x 100

(3) Elastic modulus of base film: Performed according to JIS C-2318.

(4) Intrinsic viscosity 0.2 g of polyester with phenol / 1,1,2,2-tetrachloroethane (60/4)
It was dissolved in 50 ml of a mixed solvent of 0 (weight ratio)) and measured at 30 ° C. using an Ostwald viscometer.

(5) Three-dimensional surface roughness SRa, SRz, SRy
Using a stylus type three-dimensional roughness meter (SE-3AK, manufactured by Kosaka Research Institute Co., Ltd.), the cutoff value in the longitudinal direction of the film is 0.25 mm under the conditions of a needle radius of 2 μm and a load of 30 mg. It was measured at a needle feed rate of 0.1 mm / sec over a measurement length of 1 mm, divided into 500 points at a pitch of 2 μm, and the height of each point was incorporated into a three-dimensional roughness analyzer (SPA-11). The same operation was continuously performed 150 times in the width direction of the film at intervals of 2 μm, that is, over 0.3 mm in the width direction of the film, and the data was taken into the analyzer. Next, the central surface average roughness (SRa), the ten-point average roughness (SRz), and the maximum height (SRy) were determined using an analyzer.

(6) Number of protrusions of 0.5 μm or more on the surface of the base film on the surface side to be vaporized and number of protrusions of 2.0 μm or more on the back surface of the base film A test piece having a width of 100 mm and a length of 100 mm in the longitudinal direction of the base film. Was cut out, and this was inserted between two polarizing plates to make a cross Nicol state, and the state was set so that the extinction position was maintained. In this state, using the Nikon universal projector V-12 (measurement conditions: projection lens 50 times, transmitted illumination luminous flux switching knob 50 times, transmitted light inspection), the part where light is transmitted and appears to shine (scratches, foreign matter) The major axis of the lens was 50 μm or more. The portion detected in this way is cut out from the test piece to an appropriate size, and a three-dimensional shape measuring device (Micromap TYPE 550 manufactured by Ryoka System Co., Ltd .; measurement conditions: wavelength 550 nm, WAVE mode, objective lens 10 times) is used. It was observed and measured from a direction perpendicular to the film surface. At this time, the unevenness that approaches within 50 μm when observed from the direction perpendicular to the film surface is assumed to be the same scratches and a rectangle that covers them as foreign matter, and the length and width of this rectangle are the scratches and the length of the foreign matter. The width and width. With respect to these scratches and foreign substances, the number of defects was quantified using a cross-sectional image (SURFACEPROFILE DISPLAY). The measurement was performed on 20 test pieces and converted into the number of defects per 1 m ² . Regarding the surface of the base film on the surface side to be vapor-deposited, the number of defects was counted when the height difference (difference between the highest point and the lowest point) was 0.5 μm or more. Regarding the back surface of the base film, the number of defects of those having a height difference of 2.0 μm or more was counted.

(7) Mirror glossiness Based on the mirror glossiness measurement method of JIS Z8741 (1997), when the incident angle is 60 ° on a glass surface having a refractive index of 1.567, a reflectance of 10% is measured as a glossiness of 100 (%). Is the value. The measurement conditions for glossiness are as follows. The mirror glossiness was measured from the release surface side of the transfer film.
Measurement conditions: Gs (60 °)
Measuring device: Digital gloss meter "(GM-3D)" manufactured by Murakami Color Technology Research Institute Co., Ltd.

<Manufacturing of polyester resin for base film>
(Manufacture of particle-free polyester (PET (X)))
When the temperature of the esterification reaction can reached 200 ° C., 86.4 parts by mass of terephthalic acid and 64.6 parts by mass of ethylene glycol were charged, and 0.017 parts by mass of antimony trioxide was used as a catalyst while stirring. 0.064 parts by mass of magnesium acetate tetrahydrate and 0.16 parts by mass of triethylamine were charged. Then, the pressure was raised and the pressure esterification reaction was carried out under the conditions of a gauge pressure of 0.34 MPa and 240 ° C., the esterification reaction can was returned to normal pressure, and 0.014 parts by mass of phosphoric acid was added. Further, the temperature was raised to 260 ° C. over 15 minutes, and 0.012 parts by mass of trimethyl phosphate was added. Then, after 15 minutes, dispersion treatment was carried out with a high-pressure disperser, and after 15 minutes, the obtained esterification reaction product was transferred to a polycondensation reaction can, and a polycondensation reaction was carried out under reduced pressure at 280 ° C.

After completion of the polycondensation reaction, filtration is performed with a Naslon filter having a 95% cut diameter of 5 μm, extruded into strands from a nozzle, and cooled and solidified using cooling water that has been previously filtered (pore diameter: 1 μm or less). , Cut into pellets. The intrinsic viscosity of the obtained polyethylene terephthalate resin (X) was 0.62 dl / g, and the content of the cyclic trimer was 1.05% by mass. Inactive particles and internally precipitated particles were substantially not contained. (Hereafter, it is abbreviated as PET (X).)

(Polyester containing calcium carbonate particles (manufacturing of PET (Z-Ca)))
In the manufacture of PET (X)
15 minutes after the temperature was raised to 260 ° C. and trimethyl phosphate was added, the ethylene glycol slurry of the following calcium carbonate particles was added to the produced polyester so as to be 10000 ppm.
-Polyethylene terephthalate containing calcium carbonate particles having an intrinsic viscosity of 0.63 dl / g was obtained in the same manner except that the filtration process was performed with a Naslon filter (manufactured by Nippon Seisen Co., Ltd.) having a 95% cut diameter of 20 μm. It was.
For the ethylene glycol slurry of calcium carbonate particles, calcium carbonate particles (manufactured by Fuji Silicia) having an average particle diameter of 0.6 μm are charged in ethylene glycol and further filtered through a viscose rayon filter having a 95% cut diameter of 30 μm. It was processed and manufactured.

(Silica particle-containing polyester (manufacture of PET (Z-Si1)))
In the production of PET (Z-Ca), the same procedure was carried out except that porous colloidal silica having an average particle size of 0.2 μm was used as silica particles instead of calcium carbonate particles.

(Silica particle-containing polyester (manufacture of PET (Z-Si2)))
In the production of PET (Z-Ca), the same procedure was carried out except that porous colloidal silica having an average particle size of 0.06 μm was used as silica particles instead of calcium carbonate particles.

(Production of Crosslinked Polystyrene Particle-Containing Polyester (PET (Z-St)) A vented twin-screw extruder was supplied with PET (X) and a 10% by mass aqueous dispersion of crosslinked polystyrene particles having an average particle size of 0.30 μm, and 280. Moisture was removed by heating and melting at ° C. at a reduced pressure of 1 kPa or less at the vent hole. The melted polyester was filtered with a 95% cut diameter 20 μm Naslon filter, extruded into strands from a nozzle, and pre-filtered. It was cooled, solidified, and cut into pellets using treated cooling water (pore size: 1 μm or less). The obtained crosslinked polystyrene particle-containing polyester (PET (Z-St)) had an intrinsic viscosity of 0.62 dl / g. The crosslinked polystyrene particle content was 10000 ppm.

(Manufacturing of film A1)
Particle-free PET (X) resin pellets as a raw material for the release surface side layer of the base film are dried under reduced pressure (1 Torr) at 135 ° C. for 6 hours and then supplied to the extruder 1 to supply the opposite surface layer (back surface layer). A blend of PET (X) resin pellets and polyester (PET (Z-Ca) resin pellets containing particles) containing particles as a raw material is dried and supplied to the extruder 2 at 285 ° C. The two types of molten polymers were filtered through a filter medium of a stainless sintered body (nominal filtration accuracy of 10 μm particles 95% cut), laminated with a two-type two-layer confluence block, and made into a sheet from the base. After extruding, it was wound around a casting drum having a surface temperature of 30 ° C. using an electrostatic application casting method and cooled and solidified to prepare an unstretched film.

The unstretched film is heated to 105 ° C. using a heated roll group and an infrared heater, then stretched 3.3 times in the traveling direction by the roll group having a peripheral speed difference, and then guided to a tenter stretching machine to form the film. While gripping the end with a clip, the film was stretched 3.5 times in the width direction at a temperature of 125 ° C. Subsequently, while maintaining the width stretched in the width direction, heat fixing treatment was performed at a temperature of 225 ° C. for 10 seconds, and further a relaxation treatment of 3.0% was performed. Subsequently, the surface of the release surface side layer was subjected to corona treatment and wound up to obtain a biaxially stretched film. The thickness of the release surface side layer was 10 μm, and the thickness of the back surface layer side was 22 μm.

(Manufacturing of film A2)
Particle-free PET (X) resin pellets were supplied to neither of the extruders 1 and 2 to prepare an unstretched film.
The same as the production of A1 was carried out except that the following coating liquid was applied to one side (back surface layer side) before leading to the tenter stretching machine.

(Coating liquid 1)
Water 50.00 parts by mass Isopropyl alcohol 36.10 parts by mass Polyester aqueous dispersion 13.00 parts by mass (Toyobo MD-1200 solid content concentration 34% by mass)
Colloidal silica 0.60 parts by mass (Nissan Chemical Industries, Ltd., MP2040, average particle size 200 nm, solid content concentration 40% by mass)
Surfactant (fluorine-based, solid content concentration 10% by mass) 0.30 parts by mass

(Manufacturing of film A3)
A blend of PET (X) resin pellets and PET (Z-Si2) resin pellets as a raw material for the base film release layer side was dried under reduced pressure (1 Torr) at 135 ° C. for 6 hours, and then supplied to the extruder 1. A blend of PET (X) resin pellets and polyester (PET (Z-Si1) and PET (Z-St)) resin pellets containing particles as a raw material for the opposite surface layer (back surface layer) is dried and extruded. The PET (X) resin pellet was dried and supplied to the extruder 3 as a raw material for the intermediate layer, and melted at 285 ° C. These three types of molten polymers are filtered through a stainless steel sintered filter medium (nominal filtration accuracy of 10 μm particles 95% cut), laminated in a three-type three-layer confluence block, and extruded into a sheet from the base. Using the electrostatic application casting method, the film was wound around a casting drum having a surface temperature of 30 ° C. and cooled and solidified to prepare an unstretched film. At this time, the discharge amount of each extruder was adjusted so that the thickness of the release surface side layer and the back surface layer became a predetermined value. The rest was the same as A1. The thickness of the release surface side layer was 5 μm, the thickness of the back surface layer side was 5 μm, and the thickness of the intermediate layer was 22 μm.

(Aluminum deposition)
The obtained films A1, A2, and A3 are slit into three equal parts in the width direction, and the release surface side of the slit rolls (A1r, A2r, A3r, respectively) on the right side (right side when viewed from the upstream side in the traveling direction). An aluminum vapor deposition layer was provided on the surface of the layer using a vacuum vapor deposition machine. The respective aluminum vapor-deposited films were A1rAl-1, A1rAl-2, A2rAl, and A3rAl.

Example 1
The aluminum-deposited film A1rAl-1 was cut into a size of A4, and the aluminum-deposited surface was rubbed with a rubbing roll wrapped with a brushed nylon cloth to perform a rubbing treatment. The rubbing was performed so as to be 45 degrees with respect to the short side of the cut out rectangle (45 degrees with respect to MD).

(Formation of retardation layer)
Subsequently, the following retardation layer forming solution was applied to the surface subjected to the rubbing treatment by the bar coating method. It was dried at 110 ° C. for 3 minutes, irradiated with ultraviolet rays and cured, and a λ / 4 retardation layer was provided.
(Solution for forming a retardation layer)
LC242 (manufactured by BASF) 75 parts by mass 20 parts by mass of the compound shown below
Trimethylolpropane Triacrylate 5 parts by mass Irgacure 379 3 parts by mass Surfactant 0.1 parts by mass Methyl ethyl ketone 250 parts by mass

Example 2
An aluminum vapor-deposited film A1rAl-1 was cut into a size of A4, and a 5% solution of a copolymerized polyester resin (Byron RV200) in toluene / methyl ethyl ketone (1/1) was applied to the aluminum-deposited surface as an anchor coat and dried to 2 μm. Anchor coat layer was provided. Further, the following coating agent was applied as a release layer on it, and dried in a heating oven at 150 ° C. for 3 minutes. The thickness of the release layer was 1 μm.
(Release layer coating agent)
・ Melamine cross-linked alkyl-modified alkyd resin (Hitachi Kasei Polymer Co., Ltd .: Tessfine 322: solid content 40%) 10 parts by mass ・ P-toluenesulfonic acid (Hitachi Kasei Polymer Co., Ltd .: dryer 900) 0.1 parts by mass ・ Solvent ( Toluene / methylethylketone = 1/1 part by mass) 40 parts by mass The coating liquid was filtered through a 2 μm filter.

(Formation of rubbing treatment alignment layer)
A coating material for a rubbing treatment alignment layer having the following composition was applied to the release layer surface using a bar coater, and dried at 80 ° C. for 5 minutes to form a film having a thickness of 200 nm. Subsequently, the surface of the obtained film was treated with a rubbing roll wrapped with a brushed nylon cloth to obtain a base film on which a rubbing alignment treatment layer was laminated. The rubbing was performed so as to be 45 degrees with respect to the short side of the cut out rectangle (45 degrees with respect to MD).

Fully saponified polyvinyl alcohol Molecular weight 800 2 parts by mass Ion-exchanged water 100 parts by mass
Surfactant 0.5 parts by mass

(Formation of retardation layer)
A λ / 4 retardation layer was provided on the rubbing orientation treatment layer in the same manner as in Example 1.

Example 3
(Formation of photoalignment layer)
(Synthesis of paint for photo-alignment layer)
Based on the description of Example 1, Example 2, and Example 3 of JP2013-33248, a cyclopentanone 5% by mass solution of the polymer of the following formula was produced.

(Formation of photoalignment layer)
A release layer was provided in the same manner as in Example 2, and a paint for a photoalignment layer having the above composition was applied to the release layer surface using a bar coater and dried at 80 ° C. for 1 minute to form a film having a thickness of 150 nm. Subsequently, polarized UV light was irradiated to laminate the photoalignment layer. The electric field vibration direction of the polarized ultraviolet rays was set to 45 degrees with respect to the short side of the cut out rectangle (45 degrees with respect to MD).

(Formation of retardation layer)
A λ / 4 retardation layer was provided on the photoalignment treatment layer in the same manner as in Example 1.

Examples 4, 5, 6
A λ / 4 retardation layer was provided on the rubbing-treated aluminum vapor-deposited film in the same manner as in Example 1 except that A1rAl-2, A2rAl, and A3rAl were used as the aluminum-deposited film, respectively.

Comparative Example 1
The side surface of the release layer of the polyester film A1 was not subjected to corona treatment, and a rubbing treatment alignment layer and a retardation layer were provided in the same manner as in Example 2.

(Light leakage inspection)
A transfer laminate (transfer film provided with a retardation layer) was placed on a glass plate with the retardation layer facing up, and a polarizing plate was placed 2 cm above the glass plate so as to cover the retardation surface via a spacer. .. A COB surface emitting type white LED was irradiated from above the polarizing plate, and the extinction state was observed by a CCD camera installed above the polarizing plate. The orientation direction (rubbing direction) of the λ / 4 retardation layer and the quenching axis direction of the polarizing plate were set to 45 degrees.
⊚: There was no bright spot and the whole was extinguished.
◯: A slight amount of transmitted light was observed compared to the extinguished state.
Δ: Although transmitted light was observed, it was possible to evaluate the phase difference state.
X: There was a lot of transmitted light, and it was difficult to evaluate the phase difference state.

In each of the examples, a slight amount of transmitted light was observed due to the wavelength dispersibility of the λ / 4 retardation layer, but the retardation layer could be inspected. When the wavelength dispersibility is controlled by a combination of the λ / 4 retardation layer and the λ / 2 retardation layer, it is considered that the quenching state is obtained.
In addition, an oriented liquid crystal compound layer having a uniform quenching state on the entire surface and an orientation state as designed was created on the entire surface.

Furthermore, in the evaluation of the comparative example, a mirror was used instead of the glass plate, and the evaluation was performed in the same manner as described above.
Separately, a transfer film having a polarizing plate and a retardation layer provided on a glass plate is placed with the retardation layer facing up, and a λ / 4 wave plate is placed on the transfer film with the retardation layer of the sample. It was canceled and placed in a direction that allows it to return to the original linearly polarized light. A polarizing plate was placed 2 cm above this via a spacer, a COB surface emitting type white LED was irradiated from below, and the state of quenching by transmitted light was observed with a CCD camera. The orientation direction (rubbing direction) of the λ / 4 retardation layer and the absorption axis direction of the lower polarizing plate were set to 45 degrees, and the two polarizing plates were made to be cross Nicol.
The evaluation was performed according to the same criteria as above, but in each case, the state was not extinguished, the base film was colored by retardation, and the retardation layer could not be evaluated.

(Pinhole inspection)
In the above light leakage test, the quenching state was further observed with the naked eye (center portion 15 cm × 20 cm) and a 20-fold magnifying glass (5 cm × 5 cm), and evaluated according to the following criteria.
⊚: No bright spots were observed with the naked eye, and almost no bright spots were observed by loupe observation (2 or less at 5 cm × 5 cm).
◯: No bright spots were observed with the naked eye, and a small number of bright spots were observed by loupe observation (3 or more and 20 or less in 5 cm × 5 cm).
Δ: No bright spots were observed with the naked eye, but bright spots were observed by loupe observation (more than 20 at 5 cm × 5 cm).
X: Bright spots were observed with the naked eye, or there was an overall light leakage that was not observed but was considered to be due to the presence of many bright spots observed by loupe observation.

(Pinhole inspection after stacking)
The retardation layer installation surface and the opposite surface of the transfer laminate obtained in each example were overlapped and a weight of 1 kg / cm ² was applied for 10 minutes. The defects of the retardation layer of this sample were inspected in the same manner as the pinhole inspection.

(Manufacturing of substrate laminated polarizer)
An unstretched film having a thickness of 100 μm was prepared using polyethylene terephthalate having an ultimate viscosity of 0.63 as a thermoplastic resin base material, and polyvinyl having a degree of polymerization of 2400 and a degree of saponification of 99.9 mol% was prepared on one side of the unstretched film. An aqueous solution of alcohol was applied and dried to form a PVA layer.
The obtained laminate was stretched twice in the longitudinal direction between rolls having different peripheral speeds at 120 ° C. and wound up. Next, the obtained laminate was treated with a 4% boric acid aqueous solution for 30 seconds, and then immersed in a mixed aqueous solution of iodine (0.2%) and potassium iodide (1%) for 60 seconds for staining. Subsequently, it was treated with a mixed aqueous solution of potassium iodide (3%) and boric acid (3%) for 30 seconds.
Further, this laminate is uniaxially stretched in the longitudinal direction in a mixed aqueous solution of boric acid (4%) and potassium iodide (5%) at 72 ° C., subsequently washed with a 4% potassium iodide aqueous solution, and the aqueous solution is prepared with an air knife. After removal, the mixture was dried in an oven at 80 ° C., both ends were slit and wound to obtain a substrate laminated polarizer having a width of 30 cm and a length of 1000 m. The total draw ratio was 6.5 times, and the thickness of the polarizer was 5 μm. The thickness was read by embedding a base material laminated polarizer in an epoxy resin, cutting out a section, and observing it with an optical microscope.

(Creation of polarizing plate)
After adhering the polarizer surface of the above-mentioned substrate laminated polarizer to a super birefringent polyester film (Cosmo Shine (R) SRF thickness 80 μm manufactured by Toyobo Co., Ltd.) using an ultraviolet curable adhesive, the substrate laminate The substrate was peeled off. Further, a commercially available optical adhesive sheet was laminated on the polarizer surface of the polarizing element. The release film of the pressure-sensitive adhesive sheet is peeled off, the oriented liquid crystal compound layer surface of the transfer film on which the oriented liquid crystal compound layer of the example is laminated and the pressure-sensitive adhesive layer are bonded, and then the transfer film of each example is peeled off. Obtained a circularly polarizing plate.

The obtained circularly polarizing plate was placed on a mirror with the λ / 4 retardation layer facing down, and a COB surface emitting type white LED was irradiated from above to inspect the antireflection function.
All the samples were almost extinguished on the entire surface, had no pinholes, and had an excellent antireflection function.
The slow axis of the Cosmoshine (R) SRF and the quenching axis of the polarizer should be perpendicular to each other, and the MD direction of the Cosmoshine (R) SRF and the MD direction of the transfer film of the example should be parallel. I made it.

Claims (7)

A transfer film for transferring an oriented liquid crystal compound layer.
The transfer film is an oriented liquid crystal compound in which a metal thin film layer is laminated on at least one surface of the base film and has a release surface on the side opposite to the side on which the base film of the metal thin film layer is laminated. Film for layer transfer. The film for transferring an oriented liquid crystal compound layer according to claim 1, wherein the base film is a biaxially stretched polyester film. The film for transferring an oriented liquid crystal compound layer according to claim 1 or 2, wherein the surface roughness SRa of the release surface is 30 nm or less. The film for transferring an oriented liquid crystal compound layer according to any one of claims 1 to 3, wherein the metal thin film layer is a vapor-deposited layer of aluminum. A laminate for transferring an oriented liquid crystal compound layer in which a base film, a metal thin film layer, and an oriented liquid crystal compound layer are laminated in this order. In the step (A) of preparing the aligned liquid crystal compound layer transfer laminate in which the base film, the metal thin film layer, and the oriented liquid crystal compound layer are laminated in this order, the oriented liquid crystal compound layer surface of the oriented liquid crystal compound layer transfer laminate is prepared. A method for producing an oriented liquid crystal compound layer laminate, which comprises a step (B) of laminating on the surface of the object to be transferred and a step (C) of peeling off the film for transferring the oriented liquid crystal compound layer and transferring the oriented liquid crystal compound layer to the surface of the object. .. A method for inspecting the orientation state of the alignment liquid crystal compound layer of the alignment liquid crystal compound layer transfer laminate in which the base film, the metal thin film layer, and the alignment liquid crystal compound layer are laminated in this order, for transfer of the alignment liquid crystal compound layer. A method for inspecting a laminated body for transferring an oriented liquid crystal compound layer, which comprises a step (a) of irradiating polarized light from the oriented liquid crystal compound layer side of the laminated body and a step (b) of receiving the reflected polarized light.