JPWO2014178395A1 - Transfer film and optical film - Google Patents

Abstract

An object of this invention is to provide the transfer film which can provide the optical film which is thin and is excellent in self-supporting property, and an optical film. The transfer film of the present invention is a transfer film comprising a peelable support and an optical film laminated so as to be peelable on the peelable support, wherein the optical film contains a liquid crystal compound. A non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer, the acrylic resin in the non-thermoplastic acrylic resin layer has a polyoxyalkylene chain, and the content of the polyoxyalkylene chain is 8-60 mass% with respect to the total mass of the non-thermoplastic acrylic resin layer, the thickness of the non-thermoplastic acrylic resin layer is 5-25 μm, and the thickness of the optically anisotropic layer is 0.1-10 μm. The thickness of the non-thermoplastic acrylic resin layer is larger than the thickness of the optically anisotropic layer.

Description

  The present invention relates to a transfer film and an optical film.

Retardation plates have a great many applications, and are already used in reflective liquid crystal display devices, transflective liquid crystal display devices, brightness enhancement films, optical disk pickups and PS conversion elements.
As such a retardation plate, a retardation plate is proposed in which an optically anisotropic layer in which a discotic liquid crystal compound (disc-like liquid crystal compound) or a rod-like liquid crystal compound is aligned and fixed in a predetermined direction is formed on a polymer film. (Patent Document 1). As described in Patent Document 1, usually, when an optically anisotropic layer is formed, it is formed on a transparent support such as a cellulose triacetate film and used integrally with the transparent support.

On the other hand, in recent years, thinning of electronic devices such as display devices has been demanded, and accordingly, thinning of members used for these devices has been strongly demanded. However, when using a transparent support as described in Patent Document 1, it is difficult to reduce the thickness of the transparent support itself, and it has not been possible to sufficiently meet recent demands.
On the other hand, a transfer method described in Patent Document 2 is also disclosed as another method for manufacturing an optically anisotropic layer.

JP 2004-53841 A JP 2013-7887 A

The present inventors have studied the transfer method described in Patent Document 2 with the aim of developing a retardation plate that does not include a transparent support used in Patent Document 1 or the like in order to reduce the thickness of the member. . More specifically, a thin optically anisotropic layer was formed on the temporary support, and the handleability was examined.
As a result of the above examination, in the laminated film including the optically anisotropic layer and the additive layer specifically described in the example of Patent Document 2, the film itself is fragile and breaks. It was found that it cannot be used as a phase difference plate. That is, by itself, it could not be used as a self-supporting film (film), only an optical film with poor so-called self-supporting properties was obtained, and it could not be used as a transfer film.

An object of this invention is to provide the transfer film which can provide the optical film which is thin and excellent in a self-supporting property in view of the said situation.
Another object of the present invention is to provide a thin optical film having excellent self-supporting properties.

As a result of intensive studies on the problems of the prior art, the present inventors have found that the above problem can be solved by using a non-thermoplastic acrylic resin layer containing a predetermined amount of polyoxyalkylene chains.
That is, it has been found that the above object can be achieved by the following configuration.

(1) A transfer film comprising a peelable support and an optical film laminated in a peelable manner on the peelable support,
The optical film comprises an optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The acrylic resin in the non-thermoplastic acrylic resin layer has a polyoxyalkylene chain,
The content of the polyoxyalkylene chain is 8 to 60% by mass relative to the total mass of the non-thermoplastic acrylic resin layer,
The thickness of the non-thermoplastic acrylic resin layer is 5 to 25 μm, the thickness of the optical anisotropic layer is 0.1 to 10 μm, and the thickness of the non-thermoplastic acrylic resin layer is thicker than the thickness of the optical anisotropic layer. , Transfer film.
(2) The transfer film according to (1), wherein the content of the polyoxyalkylene chain is 12 to 60% by mass with respect to the total mass of the non-thermoplastic acrylic resin layer.
(3) A transfer film comprising a peelable support and an optical film laminated in a peelable manner on the peelable support,
The optical film comprises an optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The thickness of the non-thermoplastic acrylic resin layer is 5 to 25 μm, the thickness of the optical anisotropic layer is 0.1 to 10 μm, and the thickness of the non-thermoplastic acrylic resin layer is thicker than the thickness of the optical anisotropic layer. ,
The transfer film in which the number of bending times of the optical film obtained from the following bending test A is 10 times or more.
(Bending test A: Transfer film is cut to 10 cm × 10 cm, and the transfer film cut on a horizontal base is placed so that the peelable support faces the horizontal base, and the optical film in the transfer film is placed on one side. After peeling from the peelable support to half the length from the side to the other side and returning the peeled part of the optical film to the peelable support horizontally, the peeled part peels off the tip of the peeled part The process of lifting up to be perpendicular to the support and then returning the peeled portion to the original position is repeated. The number of times of bending that causes cracks in the optical film is N, and (N-1) is the number of times of bending. )
(4) having an optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The acrylic resin in the non-thermoplastic acrylic resin layer has a polyoxyalkylene chain,
The content of the polyoxyalkylene chain is 8 to 60% by mass relative to the total mass of the non-thermoplastic acrylic resin layer,
The thickness of the non-thermoplastic acrylic resin layer is 5 to 25 μm, the thickness of the optical anisotropic layer is 0.1 to 10 μm, and the thickness of the non-thermoplastic acrylic resin layer is thicker than the thickness of the optical anisotropic layer. , Optical film.
(5) The optical film as described in (4) whose content of a polyoxyalkylene chain is 12-60 mass% with respect to the non-thermoplastic acrylic resin layer total mass.
(6) An optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The thickness of the non-thermoplastic acrylic resin layer is 5 to 25 μm, the thickness of the optical anisotropic layer is 0.1 to 10 μm, and the thickness of the non-thermoplastic acrylic resin layer is thicker than the thickness of the optical anisotropic layer. ,
The optical film whose bending frequency calculated | required from the following bending tests B is 10 times or more.
(Bending test B: After the optical film was cut to 10 cm × 10 cm and the cut optical film was placed on a horizontal base, up to half the length from one side of the optical film to the other side was the base. The number of bending operations in which the optical film is cracked by repeating the bending operation to lift one side of the optical film until the optical film part peeled off from the table is perpendicular to the table, and then return to the original position. Is N, and (N-1) is the number of bendings.)

ADVANTAGE OF THE INVENTION According to this invention, the transfer film which can provide the optical film which is thin and is excellent in self-supporting property can be provided.
Moreover, according to this invention, the optical film which is thin and excellent in self-supporting property can also be provided.

It is sectional drawing of the 1st embodiment of the transfer film of this invention. It is sectional drawing of the other aspect of the 1st embodiment of the transfer film of this invention. It is a top view which shows an example of a pattern optical anisotropic layer. It is the schematic at the time of peeling a peelable support body from the transfer film of this invention. It is sectional drawing of the 2nd embodiment of the transfer film of this invention. It is sectional drawing of the 3rd embodiment of the transfer film of this invention. It is a schematic diagram which shows the implementation method of the bending test A.

Hereinafter, the present invention will be described in detail. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value. First, terms used in this specification will be described.
In the present specification, “visible light” means 380 nm to 780 nm. Moreover, in this specification, when there is no special mention about a measurement wavelength, a measurement wavelength is 550 nm.
In addition, in this specification, an angle (for example, an angle such as “90 °”) and a relationship thereof (for example, “vertical”, “orthogonal”, “parallel”, “same direction”, “intersection at 45 °”, etc.) The range of errors allowed in the technical field to which the present invention belongs is included. At this time, the allowable error means, for example, that the angle is within a range of strict angle ± 10 ° or less, and the error from the strict angle is preferably 5 ° or less, More preferably, it is 3 ° or less.

First, the features of the transfer film of the present invention with respect to the prior art will be described in detail.
In the transfer film of this invention, the point which provided the non-thermoplastic acrylic resin layer adjacent to an optically anisotropic layer in the optical film arrange | positioned on a peelable support body is mentioned. As described above, the optically anisotropic layer containing a liquid crystal compound is thin, and easily cracks by itself, and has poor self-supporting properties. Therefore, in the past, it was common to protect with a transparent support (for example, a tack film) having a thickness of about 80 μm. On the other hand, since the non-thermoplastic acrylic resin layer obtained by polymerizing acrylic monomers has a three-dimensional cross-linking structure as will be described later, a high hardness is obtained, and a film having a thickness of about 10 μm is formed by coating or the like. It has been used as a hard coat for protecting the surface of a support or the like. However, it is easy to crack when bent, and it cannot be easily peeled off from a transparent support or the like, and it has been considered that its use is not appropriate from the viewpoint of producing a film having self-supporting properties.
As a result of intensive studies, the inventor provided a non-thermoplastic acrylic resin layer (hard coat layer) having a predetermined thickness containing a predetermined amount of polyoxyalkylene chains in a form adjacent to the thin optically anisotropic layer. Have found that the above problems can be overcome. More specifically, the optically anisotropic layer and the non-thermoplastic acrylic resin layer are both relatively fragile in a single layer, but the optical film in which both layers are laminated has high flexibility and is repeatedly bent. However, it has been found that cracks are difficult to enter. Such an optical film can be easily peeled off from the temporary support, and can be handled as a film excellent in flatness (flatness) since the occurrence of warpage (curl) is suppressed even after peeling.
In the present specification, the film having excellent self-supporting property is intended to be a film that is also excellent in mechanical strength of the film itself, can be used as a self-supporting film, and can be used as a self-supporting film. A film excellent in flatness in which the occurrence of curling is suppressed is preferable.

  In the present invention, it has also been found that a transfer film and an optical film that exhibit a predetermined number of bendings when the transfer film and the optical film are subjected to a predetermined bending test exhibit the above-described effects.

  As a preferred embodiment of the transfer film of the present invention, an optically anisotropic layer containing a liquid crystal compound is first formed on a peelable support, and a layer containing an acrylic monomer is applied thereon. A transfer film provided with the optical film formed by forming the non-thermoplastic acrylic resin layer polymerized by exposure etc. after formation is mentioned.

<First Embodiment>
A sectional view of the first embodiment of the transfer film in the present invention is shown in FIG.
In addition, the figure in this invention is a schematic diagram, and the relationship of the thickness of each layer, positional relationship, etc. do not necessarily correspond with an actual thing. The same applies to the following figures.
The transfer film 10 shown in FIG. 1 has a peelable support 12, an optically anisotropic layer 14, and a non-thermoplastic acrylic resin layer 16 (hereinafter also simply referred to as a resin layer) in this order. The optically anisotropic layer 14 and the resin layer 16 constitute an optical film 18. The peel strength at the interface between the peelable support 12 and the optical film 18 is smaller than the peel strength between the optically anisotropic layer 14 and the resin layer 16.
In FIG. 1, the optical anisotropic layer 14 is disposed on the peelable support 12 side in the optical film 18, but the stacking order is not limited to this mode, and the peelable support is shown in FIG. The transfer film 100 which has the body 12, the resin layer 16, and the optically anisotropic layer 14 in this order may be sufficient.
Below, each member which comprises the transfer film 10 is explained in full detail.

[Peelable support]
A peelable support (also referred to as a temporary support) is a base material that supports an optical film described later, and is in close contact with the surface of the optical film so as to be peelable. As will be described later, when the transfer film is used, it is separated into a peelable support and an optical film.
Note that the “peelability” of the peelable support is the peelable support without peeling at the interface between the optically anisotropic layer and the resin layer when an external force for peeling the optical film is applied to the transfer film. It means the property of peeling at the interface between the body and the optical film, and the property is determined by the relationship with the optical film in contact with the peelable support.

As a method for controlling the relationship between the peel strength of the peelable support and the optical film, a known method can be employed.
For example, when a polyvinyl alcohol-based alignment film or the like is used when forming the optically anisotropic layer, and when the alignment film is not hardened, it is easily between the alignment film and the optically anisotropic layer. Peeling occurs. This aspect corresponds to a second embodiment to be described later. In this case, the alignment film is included as a part of the peelable support.
Further, when the alignment film is hardened, peeling easily occurs between the alignment film and the support. This aspect corresponds to a third embodiment to be described later, and in this case, the alignment film is included as a part of the optical film.
Note that the alignment film can be used for assisting adhesion to other materials, and therefore, whether the alignment film is included in the peelable support or the optical film can be appropriately selected depending on the subsequent usage.
Further, a base material such as polyethylene terephthalate can be rubbed directly without providing an alignment film, and then an optically anisotropic layer can be formed. In this case, peeling easily occurs between the substrate and the optically anisotropic layer.

Examples of the material constituting the releasable support include, for example, cellulose polymers; acrylic polymers having acrylic ester polymers such as polymethyl methacrylate and lactone ring-containing polymers; thermoplastic norbornene polymers; polycarbonate polymers; Polyester polymers such as terephthalate and polyethylene naphthalate; Styrene polymers such as polystyrene and acrylonitrile / styrene copolymers (AS resin); Polyolefin polymers such as polyethylene, polypropylene and ethylene / propylene copolymers; Vinyl chloride polymers; Amide polymers such as nylon and aromatic polyamide; imide polymers; sulfone polymers; polyether sulfone polymers; polyether ether ketone polymers; Rensurufido polymers; like or polymer obtained by mixing these polymers; vinylidene chloride polymer; vinyl alcohol-based polymer, vinyl butyral-based polymers; arylate polymers; polyoxymethylene polymers, epoxy based polymers.
Of these, polyester polymers are preferable and polyethylene terephthalate is more preferable because they are excellent in peelability and can be directly rubbed.

The thickness of the peelable support is not particularly limited, but is preferably 10 to 150 μm, more preferably 20 to 100 μm, from the viewpoint of excellent handling properties of the transfer film.
In addition, even if a peelable support body is comprised by 1 layer, the laminated structure of two or more layers may be sufficient so that it may mention later.

[Optical film]
The optical film is detachably laminated on the peelable support and functions as a retardation plate. The optical film has at least an optically anisotropic layer and a resin layer that are adjacent to each other. As will be described later, the optical film is used by being peeled from the peelable support, and is used by being bonded to a display device or the like.
Hereinafter, the optically anisotropic layer and the resin layer contained in the optical film will be described in detail.

(Optically anisotropic layer)
The optically anisotropic layer in the optical film is an optically anisotropic layer containing a liquid crystal compound.
When an optical film is used for a circularly polarizing plate, the optically anisotropic layer preferably has a retardation region having a retardation of about λ / 4, specifically, because it can be approximated to more accurate circularly polarized light. The in-plane retardation (Re (550)) measured at a wavelength of 550 nm is preferably 110 to 165 nm, more preferably 115 to 150 nm, and particularly preferably 120 to 145 nm.
In this specification, Re (λ) and Rth (λ) represent in-plane retardation and retardation in the thickness direction at the wavelength λ, respectively. Re (λ) and Rth (λ) are measured with KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments Co., Ltd.) with light having a wavelength of λ nm incident in the normal direction of the film.

Because the optically anisotropic layer can produce clockwise circularly polarized light and counterclockwise circularly polarized light, respectively, the first retardation region and the second retardation region are different from each other in at least one of the in-plane slow axis direction and the in-plane retardation. It is also preferable that the patterned optically anisotropic layer includes a retardation region, and the first retardation region and the second retardation region are alternately arranged in the plane. More specifically, as shown in FIG. 3, the phase difference between the first retardation region 140a and the second retardation region 140b in the optical anisotropic layer 140 is about λ / 4, and the in-plane slow axis There is an embodiment in which the directions of 142a and 142b are different by 90 °.
An optical film having such an optically anisotropic layer is suitably used in a so-called FPR method (Film Patterned Retarder method) among 3D image display devices.

Although the kind of liquid crystal compound contained in the optically anisotropic layer is not particularly limited, it can be classified into a rod-shaped type (rod-shaped liquid crystal compound) and a disk-shaped type (discotic liquid crystal compound (disk-shaped liquid crystal compound)) according to the shape of the liquid crystal compound. In addition, there are low and high molecular types, respectively. Polymer generally refers to a polymer having a degree of polymerization of 100 or more (Polymer Physics / Phase Transition Dynamics, Masao Doi, 2 pages, Iwanami Shoten, 1992). In the present invention, any liquid crystal compound can be used, and two or more rod-like liquid crystal compounds, two or more disc-like liquid crystal compounds, or a mixture of a rod-like liquid crystal compound and a disc-like liquid crystal compound may be used. In order to fix the liquid crystal compound described above, the optically anisotropic layer is more preferably formed using a liquid crystal compound having a polymerizable group (rod-like liquid crystal compound or discotic liquid crystal compound). When the liquid crystal compound has a polymerizable group, it is preferable to have two or more polymerizable groups in one molecule. In addition, the kind in particular of polymerizable group is not restrict | limited, The functional group in which addition polymerization reaction is possible is preferable, and a polymerizable ethylenically unsaturated group or a ring-polymerizable group is preferable. More specifically, a (meth) acryloyl group, a vinyl group, a styryl group, an allyl group, etc. are mentioned preferably, and a (meth) acryloyl group is more preferable. The (meth) acryloyl group is a concept including a methacryloyl group and an acryloyl group.
When the liquid crystal compound is a mixture of two or more, it is preferable that at least one liquid crystal compound has two or more polymerizable groups in one molecule.
As the rod-shaped liquid crystal compound, for example, those described in claim 1 of JP-T-11-53019 and paragraphs [0026] to [0098] of JP-A-2005-289980 can be preferably used. As the liquid crystal compound, for example, those described in paragraphs [0020] to [0067] of JP-A-2007-108732 and paragraphs [0013] to [0108] of JP-A-2010-244038 can be preferably used. However, it is not limited to these.

  In order to set the retardation in the optically anisotropic layer to about λ / 4, the alignment state of the liquid crystal compound may be controlled. At this time, when using a rod-like liquid crystal compound, it is preferable to fix the rod-like liquid crystal compound in a horizontally aligned state. When using a discotic liquid crystal compound, the discotic liquid crystal compound is fixed in a vertically aligned state. It is preferable to do this. In the present invention, “the rod-like liquid crystal compound is horizontally aligned” means that the director of the rod-like liquid crystal compound and the layer surface are parallel, and “the discotic liquid crystal compound is vertically aligned” means that the discotic liquid crystal compound is circular. This means that the board surface and the layer surface are vertical. It is not strictly required to be horizontal or vertical, but each means a range of ± 20 ° from an accurate angle. It is preferably within ± 5 °, more preferably within ± 3 °, even more preferably within ± 2 °, and most preferably within ± 1 °.

  Moreover, in order to make a liquid crystal compound into a horizontal alignment and a vertical alignment state, you may use the additive (alignment control agent) which accelerates a horizontal alignment and a vertical alignment. Various known additives can be used as the additive.

The thickness of the optically anisotropic layer is 0.1 to 10 μm, and preferably 0.5 to 5 μm from the viewpoint of thinning.
The optically anisotropic layer may have a single layer structure or a laminated structure. In the case of a laminated structure, the total thickness is within the above range.

  In addition, when using the optical film of this invention as an optical compensation film of a twist orientation mode liquid crystal display device, the optically anisotropic layer fixed to the hybrid orientation state is preferable, for example, paragraph [1] of JP, 2012-3183, A [0123] to [0126] can be preferably used, but is not limited thereto.

(Non-thermoplastic acrylic resin layer)
The non-thermoplastic acrylic resin layer (resin layer) is a layer disposed adjacent to the optically anisotropic layer, and is a layer for ensuring the self-supporting function of the optical film. Since the non-thermoplastic acrylic resin layer has a crosslinked structure (so-called three-dimensional network structure), it has excellent mechanical strength even if the layer thickness is thin.
In the present invention, the term “non-thermoplastic” means that no melting behavior is exhibited at 200 ° C. or lower when the melting point is measured with a melting point measuring device. That is, it is intended that the melting point exceeds 200 ° C. Note that the non-thermoplastic acrylic resin layer does not have a clear melting point even when heated to over 200 ° C., and although it softens, it does not lead to melting and may change color or shrink.
Melting | fusing point measurement has the method of measuring with a capillary tube and a double tube thermometer, the method of heating up a metal heat block, and detecting a change visually or optically.

The resin layer contains an acrylic resin. The acrylic resin is cross-linked so as to form a three-dimensional network structure. That is, it has a crosslinked structure having a crosslinking point.
An acrylic resin is a polymer of a (meth) acryl monomer ((meth) acryl monomer). Here, “(meth) acryl” is a concept including acryl and methacryl. That is, the (meth) acryl monomer is a concept including an acrylic monomer and a methacryl monomer. The monomer may be a low molecular weight compound (intended for a compound having a molecular weight of 2000 or less) or a high molecular compound (intended for a compound having a molecular weight of more than 2000. Among them, preferably 2000 to 20000 or less). From the viewpoint of excellent handleability, a low molecular compound (molecular weight 2000 or less) is preferable.
The type of (meth) acrylic monomer to be used is not particularly limited, but a polyfunctional (meth) acrylic monomer containing two or more functional groups selected from the group consisting of an acryloyloxy group and a methacryloyloxy group is used. Preferably used. Specific preferred examples include alkylene di (meth) acrylate (for example, 1,6-hexanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate), ethylene glycol di (meth) acrylate, Diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, poly (butanediol) ) Di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, triisopropylene glycol di (meth) a Relate, polyethylene glycol di (meth) acrylate, bisphenol A di (meth) acrylate, di (meth) acrylate such as ethoxylated bisphenol A di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, trimethylolpropane tri (Meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol monohydroxytri (meth) acrylate, tri (meth) acrylate such as trimethylolpropane triethoxytri (meth) acrylate, pentaerythritol tetra (meth) acrylate, Tetra (meth) acrylates such as di-trimethylolpropane tetra (meth) acrylate, dipentaerythritol (monohydroxy) penta (meth) acrylate Penta (meth) acrylate and the like. Among these, a di (meth) acrylic monomer (poly (poly) ethylene chain containing a polyoxyalkylene chain such as polyoxyethylene di (meth) acrylate, polyoxypropylene di (meth) acrylate) and the like is more excellent in the self-supporting property of the optical film. Oxyalkylene di (meth) acrylate) is preferred.
Polyfunctional (meth) acrylic monomers may be used alone or in admixture of two or more.

When manufacturing an acrylic resin, monomers other than the said polyfunctional (meth) acryl monomer may be used.
For example, a (meth) acryl monomer having one acryloyloxy group or one methacryloyloxy group can also be used.
Moreover, you may use other monomers other than a (meth) acryl monomer. For example, styrene monomers such as styrene, p-methyl styrene, ethyl styrene, propyl styrene, isopropyl styrene, p-tert-butyl styrene, vinyl monomers such as vinyl acetate, vinyl propionate, vinyl pivalate, etc. Is mentioned.

  In producing the acrylic resin, a polymerization initiator may be used. As the kind of the polymerization initiator to be used, an optimal compound is appropriately selected according to the polymerization mode. Examples thereof include a thermal polymerization initiator and a photopolymerization initiator. The polymerization initiator may be contained in the composition when forming the resin layer.

  The resin layer may contain components other than the acrylic resin described above (for example, fillers (fine particles, etc.), plasticizers, UV inhibitors, etc.).

The acrylic resin in the resin layer has a polyoxyalkylene chain, and the content of the polyoxyalkylene chain is 8 to 60% by mass with respect to the total mass of the resin layer. Among them, 12 to 60% by mass is preferable, and 12 to 50% by mass is more preferable in that the self-supporting property of the optical film is further improved and the releasability of the optical film from the releasable support is more excellent. -40 mass% is further more preferable.
When the said content is less than 8 mass%, an optical film is weak and it is inferior to self-supporting property. When the content is more than 60% by mass, the optical film tends to warp, flatness is deteriorated, and as a result, the self-supporting property is inferior.
In addition, the measuring method of content of the polyoxyalkylene chain in a resin layer is not restrict | limited in particular, For example, it can calculate from preparation amount. Moreover, it can measure with a well-known method and apparatus.

A polyoxyalkylene chain (polyoxyalkylene group) is a group having an oxyalkylene group (—O—R—, R: alkylene group) as a repeating unit.
As the oxyalkylene group, an oxyalkylene group having 2 to 6 carbon atoms is preferable, and an oxyethylene group and an oxypropylene group are more preferable. One polyoxyalkylene chain may contain different types of oxyalkylene groups.
The number of repeating oxyalkylene groups is not particularly limited, but is preferably 2 to 30, more preferably 4 to 20 in terms of better self-supporting properties of the optical film.
In addition, as a method of introducing a polyoxyalkylene chain into the resin layer, for example, a method of forming a resin layer using a (meth) acrylic monomer having a polyoxyalkylene chain can be mentioned.

The resin layer has a thickness of 5 to 25 μm, preferably 5 to 15 μm, more preferably 5 to 10 μm, from the viewpoint of the balance between thinning of the optical film and self-supporting property of the optical film.
In addition, the thickness of the resin layer is thicker than the thickness of the optically anisotropic layer described above. When the thickness of the resin layer is equal to or less than the thickness of the optical anisotropic layer, the optical film is inferior in self-supporting property.

As one preferred embodiment of the optical film, the optically anisotropic layer is a layer formed by subjecting the composition A containing a liquid crystal compound having a polymerizable group to a curing treatment, and the non-thermoplastic acrylic resin layer is The aspect which is a layer formed by performing a hardening process to the composition B containing a (meth) acryl monomer is mentioned.
Moreover, as an aspect of the optical film in a transfer film, the aspect whose bending frequency calculated | required from the bending test A mentioned later is 10 times or more is mentioned, It is more preferable that the bending frequency is 15 times or more. If it is the said aspect, the flexibility of an optical film will be more excellent, and self-supporting property will be more excellent as a result.
Hereinafter, the bending test A will be described in detail with reference to FIG.
First, the transfer film 10 including the above-described peelable support 12 and the optical film 18 is cut (cut) into length: 10 cm × width: 10 cm, and the cut transfer film 10 is placed on a horizontal table (not shown). (FIG. 7A). In addition, the transfer film 10 is arrange | positioned so that the peelable support body 12 may face the stand side in that case. Next, the optical film 18 is peeled from the peelable support 12 to a position (L / 2) half the length L from the one side 18a side to the other side 18b side of the optical film 18 (FIG. 7B). )). Then, the peeling part 18c of the optical film 18 is returned to a horizontal state with respect to the peelable support 12 before peeling (FIG. 7C). Next, the tip of the peeling portion 18c of the optical film 18 is lifted until the peeling portion 18c is perpendicular to the peelable support 12 (FIG. 7D), and the peeling portion 18c is returned to its original position. (In other words, the peeled portion 18c is returned to be level with respect to the peelable support 12) (FIG. 7E) The bending process is repeated. The bending process (the processes shown in FIGS. 7C to 7E) is repeated until a crack is visually confirmed on the optical film 18. In particular, cracks are likely to occur in the center between the one side 18a and the other side 18b of the optical film 18. When a crack is confirmed on the optical film 18 during the bending process after the predetermined number N, (N-1) times is set as the above bending number. For example, when a crack is confirmed after the eleventh bending process, the tenth bending is set as the above bending number.

Moreover, as another aspect of the optical film described above, an aspect in which the number of bendings obtained from a bending test B described later is 10 or more is preferable, and the number of bendings is more preferably 15 or more. If it is the said aspect, the flexibility of an optical film will be more excellent, and self-supporting property will be more excellent as a result.
In the bending test B, the optical film was cut to 10 cm × 10 cm, and after the cut optical film was placed on a horizontal base, up to half the length from one side of the optical film to the other side was the base. The bending operation of lifting one side of the optical film and returning it to the original is repeated until the optical film part peeled off from the stage becomes perpendicular to the stage. In addition, the said operation of the bending test B repeats the bending operation which lifts up the one side part of an optical film and returns it like the aspect shown to the said FIG.7 (C)-(E). When a crack is confirmed on the optical film during the bending process after the predetermined number N, (N-1) times is set as the above bending number. For example, when a crack is confirmed after the eleventh bending process, the tenth bending is set as the above bending number.

In the transfer film 10, as described above, the peel strength at the interface between the peelable support 12 and the optical film 18 is smaller than the peel strength between the optical anisotropic layer 14 and the resin layer 16. In other words, in FIG. 1, the peel strength at the interface between the peelable support 12 and the optically anisotropic layer 14 is smaller than the peel strength between the optically anisotropic layer 14 and the resin layer 16.
More specifically, the interface between the peelable support 12 and the optical film 18 has a peel strength (x), and the interface between the peelable support 12 and the optical film 18 has a peel direction exceeding the peel strength (x). When stress is applied, the interface between the peelable support 12 and the optical film 18 peels. Further, the interface between the optically anisotropic layer 14 and the resin layer 16 has a peel strength (y), and the interface between the optically anisotropic layer 14 and the resin layer 16 has a peeling direction stress exceeding the peel strength (y). When added, the interface between the optically anisotropic layer 14 and the resin layer 16 is peeled off.
In the transfer film 10, the peel strength (x) is smaller than the peel strength (y). Therefore, when stress is applied to the transfer film 10 in the direction in which the peelable support 12 and the optical film 18 are peeled off, the transfer film 10 peels at the interface between the peelable support 12 and the optical film 18, and the peelable support 12 and the optical film are optically separated. Separate into film 18.

The method satisfying the above relationship is not particularly limited, but an optically anisotropic layer is formed from a composition A containing a liquid crystal compound having a polymerizable group on a peelable support, as described in the method for producing a transfer film described later. Then, a method of forming a resin layer from the composition B containing a (meth) acrylic monomer on the optically anisotropic layer is mentioned. According to this method, when the (meth) acrylic monomer is polymerized on the optically anisotropic layer, the polymerizable group remaining on the surface of the optically anisotropic layer and the (meth) acrylic monomer The polymerizable group ((meth) acryloyloxy group) contained therein reacts to form a strong bond between the optically anisotropic layer and the resin layer. As a result, the peel strength (x) is the peel strength. It becomes smaller than (y).
Other methods may be used as a method for adjusting the relationship between the peel strengths, and the method described in the description of the peelable support can also be used.

[Transfer Film Manufacturing Method]
The method for producing the transfer film 10 shown in FIG. 1 is not particularly limited, and a known method can be used. Especially, the method provided with the following processes is preferable at the point which the peelability of a peelable support body and an optical film is more excellent.
Step 1: Step of rubbing the surface of the peelable support Step 2: Applying composition A containing a liquid crystal compound having a polymerizable group on the peelable support to form a coating film, Step 3 of forming an optically anisotropic layer by applying a curing process: Applying composition B containing (meth) acrylic monomer on the optically anisotropic layer to form a coating film, Step of performing a curing process on the film to form a resin layer Hereinafter, the procedure of the above step will be described in detail.

(Process 1)
Step 1 is a step of rubbing the surface of the peelable support. By carrying out this step, the orientation direction of the liquid crystal compound in the optically anisotropic layer formed on the peelable support can be controlled. If the surface of the peelable support is already in the desired surface state, step 1 may not be performed.
The method of rubbing treatment is not particularly limited, and a known method can be adopted. For example, a method of obtaining the orientation by rubbing the surface of the peelable support in a certain direction using paper, gauze, felt, rubber, nylon, polyester fiber, or the like can be used. Generally, it is carried out by rubbing several times using a cloth or the like in which fibers having a uniform length and thickness are planted on average. A general method for rubbing is described in, for example, “Liquid Crystal Handbook” (issued by Maruzen, October 30, 2000).
In addition, the description in Japanese Patent No. 4052558 can also be referred to as conditions for the rubbing process.

(Process 2)
In step 2, the composition A containing a liquid crystal compound having a polymerizable group is applied onto the peelable support subjected to the alignment treatment to form a coating film, and the coating film is cured. And forming an optically anisotropic layer.
The definition of the liquid crystal compound having a polymerizable group used in the composition A is as described above.
The composition A contains components other than the liquid crystal compound (for example, a solvent (water and / or organic solvent), a polymerization initiator, an alignment controller (for example, a vertical alignment accelerator), etc.) as necessary. May be.

The method for applying the composition A onto the peelable support is not particularly limited, and is performed by a known method (for example, wire bar coating method, extrusion coating method, direct gravure coating method, reverse gravure coating method, die coating method). it can.
The thickness of the coating film (Composition A coating film) formed on the peelable support is not particularly limited, and is preferably adjusted so that the optically anisotropic layer having the thickness described above is formed.
As the curing treatment applied to the coating film, the procedure is not particularly limited as long as the polymerization of the polymerizable group can be proceeded. Usually, heat treatment or light irradiation treatment (ultraviolet ray irradiation, electron beam irradiation, etc.) Is implemented.
When the heat treatment is carried out, it is preferable to carry out the heat treatment at 90 to 150 ° C. for 10 to 120 minutes by adding an appropriate amount of a thermal polymerization initiator to the composition A.
Moreover, when a light irradiation process is implemented, it is preferable to make the composition A contain a photopolymerization initiator in an appropriate amount and to perform various light irradiations.
By performing the above treatment, the liquid crystal compound can be fixed in a predetermined alignment state.

A patterned optically anisotropic layer may be formed as the optically anisotropic layer.
As a method for forming the patterned optically anisotropic layer, various known methods can be used. For example, there is a method in which a plurality of actions for controlling the alignment of the liquid crystal compound are utilized, and thereafter, any action is eliminated by an external stimulus (heat treatment or the like) to make a predetermined alignment control action dominant. For example, the liquid crystal compound is brought into a predetermined alignment state by the combined action of the alignment control ability by the peelable support and the alignment control ability of the alignment control agent added to the liquid crystal compound, and one phase difference is fixed by fixing it. After forming the region, by external stimulus (heat treatment, etc.), one of the actions (for example, the action by the orientation control agent) disappears, and the other orientation control action (the action by the peelable support) becomes dominant. To realize another alignment state and fix it to form the other phase difference region. Details of this method are described in paragraphs [0017] to [0029] of JP 2012-008170 A, the contents of which are incorporated herein by reference.

(Process 3)
In step 3, composition B containing (meth) acrylic monomer is applied on the optically anisotropic layer formed in step 2 to form a coating film, and the coating film is subjected to curing treatment. In this step, the resin layer is formed.
The definition of the (meth) acrylic monomer used in the composition B is as described above.
The composition B may contain components other than the (meth) acrylic monomer (for example, a solvent (water and / or organic solvent), a polymerization initiator, etc.) as necessary.

The method for applying the composition B on the optically anisotropic layer is not particularly limited, and can be performed by a known method (for example, the method described above).
The thickness in particular of the coating film (composition B coating film) formed on a peelable support body is not restrict | limited, It is preferable to adjust so that the resin layer of the thickness mentioned above may be formed.
As the curing treatment applied to the coating film, the procedure is not particularly limited as long as the polymerization of the acryloyloxy group or the methacryloyloxy group in the (meth) acrylic monomer can be progressed. Treatment or light irradiation treatment (ultraviolet irradiation, electron beam irradiation, etc.) is performed. The preferred embodiment of the heat treatment and the light irradiation treatment is the same as in the above step 2.

The transfer film 10 shown in FIG. 1 can be manufactured by performing the said process 1-the process 3. FIG. As described above, when this production method is carried out, the polymerizable group remaining on the surface of the optically anisotropic layer after the step 2 and the (meth) acrylic monomer in the composition B in the step 3 It becomes possible for the acryloyloxy group or methacryloyloxy group in the inside to react, and a covalent bond is formed between the optically anisotropic layer and the resin layer, and the adhesion between them is further improved. As a result, peeling of the optical film from the peelable support can be performed more easily.
In addition, when implementing the said process, the area | region where a (meth) acryl monomer osmose | permeates the surface layer part by the side of the resin layer of an optically anisotropic layer, and acrylic resin is partially contained in the surface layer of an optically anisotropic layer May occur.

  Although the manufacturing method of the aspect of FIG. 1 was explained in full detail above, it can manufacture by reversing the order of the said process 2 and 3 as a manufacturing method of the optical film of the aspect of FIG.

[Usage of transfer film]
When using the transfer film described above, as shown in FIG. 4, both are separated with the interface between the peelable support 12 and the optical film 18 as a peeled surface. The separation procedure is not particularly limited, but a claw is inserted between the peelable support 12 and the optical film 18 to provide a trigger for peeling, and then the peelable support 12 is bent and deformed away from the optical film 18. And a method for separating the two.

  The separated optical film can be used as a circularly polarizing plate by being bonded to a polarizing film. At the time of bonding, a known pressure-sensitive adhesive layer can be used as necessary. The pressure-sensitive adhesive layer has, for example, a ratio (tan δ = G ″ / G ′) of storage elastic modulus G ′ and loss elastic modulus G ″ measured by a dynamic viscoelasticity measuring device of 0.001 to 1.5. It includes a so-called pressure-sensitive adhesive and a substance that is easy to creep. Examples of the adhesive include, but are not limited to, a polyvinyl alcohol-based adhesive.

The manufactured circularly polarizing plate is disposed on the display surface side of a display device (for example, LCD or OLED), and can provide an antireflection function.
Moreover, in the aspect which has the polarizer for image display on the visual recognition side of an image display panel, such as a transmissive mode liquid crystal panel, you may use the said optical film by directly bonding on the polarizer.

<Second Embodiment>
Next, the second embodiment of the transfer film of the present invention will be described in detail.
The transfer film 200 shown in FIG. 5 has the base material 20, the alignment film 22, the optically anisotropic layer 14, and the resin layer 16 in this order. In this embodiment, the base material 20 and the alignment film 22 constitute the peelable support 120, and the optical anisotropic layer 14 and the resin layer 16 constitute the optical film 18. In this embodiment, the peel strength at the interface between the peelable support 120 and the optical film 18 is smaller than the peel strength at the interface between the optically anisotropic layer 14 and the resin layer 16. That is, the peel strength at the interface between the alignment film 22 and the optically anisotropic layer 14 is smaller than the peel strength at the interface between the optically anisotropic layer 14 and the resin layer 16.
In this embodiment, the alignment state of the liquid crystal compound in the optically anisotropic layer 14 can be controlled more strictly by providing the alignment film 22.
As shown in FIG. 5, the transfer film 200 has the same configuration as that of the transfer film 10 except for the base material 20 and the alignment film 22. Therefore, the same reference numerals are assigned to the same components. A description thereof will be omitted, and the substrate 20 and the alignment film 22 will be described in detail below.

[Base material]
A base material is for supporting the alignment film mentioned later, The kind in particular is not restrict | limited.
Examples of the material constituting the substrate include the material constituting the peelable support described above.
Although the thickness of a base material is not restrict | limited in particular, 20-100 micrometers is preferable and 40-80 micrometers is more preferable from the point which is excellent in the handleability of a transfer film.
In addition, the base material may be composed of one layer or may be a laminated structure of two or more layers.

[Alignment film]
An alignment film is a layer arrange | positioned on the said base material, and is a layer which controls the orientation direction of the liquid crystal compound in an optically anisotropic layer. The alignment film is separated from the optical film together with the substrate.
The type of the alignment film used is not particularly limited as long as it satisfies the peeling relationship with the optical film described above.
The alignment film can be provided by means such as a rubbing treatment of an organic compound (preferably a polymer), oblique vapor deposition of an inorganic compound, or formation of a layer having a microgroove. Furthermore, an alignment film in which an alignment function is generated by application of an electric field, application of a magnetic field, or light irradiation is also known. Among the alignment films, a layer (hereinafter, also referred to as a rubbing alignment film) processed by rubbing so as to have the ability to regulate the alignment of the liquid crystal compound is preferable. In particular, the rubbing alignment film is preferably formed on the surface of the polymer film by rubbing treatment. The rubbing alignment film has an alignment axis that regulates the alignment of the liquid crystal compound, and the liquid crystal compound is aligned according to the alignment axis.
The rubbing treatment method includes the method described in the first embodiment.

  As polymers for alignment films, there are many literatures, and many commercially available products can be obtained. The polymer used in the present invention is preferably polyvinyl alcohol or polyimide, and derivatives thereof. In particular, modified or unmodified polyvinyl alcohol is preferred. Polyvinyl alcohols having various saponification degrees exist. In the present invention, those having a saponification degree of about 85 to 99 are preferably used. Commercial products may be used. For example, “PVA103”, “PVA203” (manufactured by Kuraray Co., Ltd.) and the like are PVA having the above saponification degree. For the rubbing alignment film, reference can be made to the modified polyvinyl alcohol described in WO01 / 88574A1, page 43, line 24 to page 49, line 8, and paragraph Nos. [0071] to [0095] of Japanese Patent No. 3907735.

  The thickness of the alignment film is not particularly limited, but is preferably 0.01 to 10 μm and more preferably 0.01 to 1 μm from the viewpoint of thinning.

As described above, in this embodiment, the peel strength at the interface between the peelable support and the optical film is smaller than the peel strength at the interface between the optically anisotropic layer and the resin layer. That is, the peel strength at the interface between the alignment film and the optically anisotropic layer is smaller than the peel strength at the interface between the optically anisotropic layer and the resin layer.
A method for satisfying such a relationship of the peel strength is not particularly limited, and examples thereof include a method of treating the surface of the alignment film with a release agent and a method of adjusting the type of material used for each layer. In addition, by manufacturing the optically anisotropic layer and the resin layer by the above-described steps 2 to 3, the peel strength between the optically anisotropic layer and the resin layer is determined from the peel strength between the alignment film and the optically anisotropic layer. Can also be relatively increased.

In this embodiment, the peel strength at the interface between the peelable support and the optical film is preferably smaller than the peel strength between the alignment film and the substrate. If the above relationship is satisfied, the alignment film and the substrate can be integrally separated from the optical film, and the working efficiency is improved.
In the above embodiment, as a combination of the base material and the alignment film, a cellulose acylate film subjected to saponification treatment is used as the base material, and polyvinyl alcohol having no polymerizable group is used as a material included in the alignment film. It is preferable. By using the cellulose acylate film as a substrate, the adhesion with an alignment film containing a hydrophilic material such as polyvinyl alcohol is further improved, and peeling at the interface between the substrate and the alignment film is less likely to occur. Become. As a result, peeling easily proceeds at the interface between the alignment film and the optical film.

The production method of the second embodiment of the transfer film of the present invention is not particularly limited, and a known method can be adopted. Especially, the method provided with the following processes is preferable at the point which the peelability of an optical film is more excellent.
Step 10: Step of forming an alignment film on the substrate Step 11: Step of performing a rubbing treatment on the alignment film Step 12: A composition containing a liquid crystal compound having a polymerizable group on the alignment film subjected to the rubbing treatment A is applied to form a coating film, and the coating film is cured to form an optically anisotropic layer. Step 13: Contains a (meth) acrylic monomer on the optically anisotropic layer The process of apply | coating the composition B which forms, forms a coating film, performs a hardening process with respect to a coating film, and forms a resin layer The said processes 11-13 are the same as the procedure of the said processes 1-3, respectively. The description is omitted. Below, the procedure of the process 10 is explained in full detail.

Step 10 is a step of forming an alignment film on the substrate.
The method for forming the alignment film is not particularly limited, and a known method can be adopted. For example, the method (application | coating composition for alignment film formation) containing the material which forms alignment film on a base material is apply | coated, and the hardening process is given as needed.

  In the second embodiment, when the pattern optical anisotropic layer is formed as the optical anisotropic layer, there is an aspect in which the pattern alignment film is used as the alignment film. In this embodiment, pattern alignment films having different alignment control capabilities are formed, a liquid crystal compound is disposed thereon, and the liquid crystal compound is aligned. The liquid crystal compounds achieve different alignment states depending on the alignment control ability of the pattern alignment film. By fixing each alignment state, the pattern of the 1st and 2nd phase difference area | region is formed according to the pattern of an alignment film. The pattern alignment film can be formed using a printing method, mask rubbing for the rubbing alignment film, mask exposure for the photo alignment film, or the like. A method using a printing method is preferable in that large-scale equipment is not required and manufacturing is easy. Details of this method are described in paragraphs [0166] to [0181] of JP2012-032661, and the contents thereof are incorporated herein by reference.

  As another method, for example, a photo acid generator is added to the alignment film. In this example, a photoacid generator is added to the alignment film, and pattern exposure exposes a region where the photoacid generator is decomposed to generate an acidic compound and a region where no acid compound is generated. In the light unirradiated part, the photoacid generator remains almost undecomposed, and the interaction between the alignment film material, the liquid crystal compound, and the alignment control agent added as necessary dominates the alignment state, The slow axis is oriented in a direction perpendicular to the rubbing direction. When the alignment film is irradiated with light and an acidic compound is generated, the interaction is no longer dominant, the rubbing direction of the rubbing alignment film dominates the alignment state, and the liquid crystal compound has its slow axis parallel to the rubbing direction. To parallel orientation. As the photoacid generator used in the alignment film, a water-soluble compound is preferably used. Examples of photoacid generators that can be used include Prog. Polym. Sci. , 23, 1485 (1998). As the photoacid generator, pyridinium salts, iodonium salts and sulfonium salts are particularly preferably used. Details of this method are described in Japanese Patent Application No. 2010-289360, the contents of which are incorporated herein by reference.

<Third embodiment>
Next, the third embodiment of the transfer film of the present invention will be described in detail.
The transfer film 300 shown in FIG. 6 has the peelable support 12, the alignment film 22, the optically anisotropic layer 14, and the resin layer 16 in this order. In this embodiment, the alignment film 22, the optically anisotropic layer 14, and the resin layer 16 constitute the optical film 180. Also in this embodiment, the peel strength at the interface between the peelable support 12 and the optical film 180 is the peel strength at the interface between the optically anisotropic layer 14 and the resin layer 16, and the alignment film 22 and the optically anisotropic layer. 14 is smaller than the peel strength at the interface with the material. In other words, the peel strength at the interface between the peelable support 12 and the alignment film 22 is the peel strength at the interface between the optically anisotropic layer 14 and the resin layer 16, and the alignment film 22 and the optically anisotropic layer 14. It is smaller than the peel strength at the interface.
In this embodiment, the alignment state of the liquid crystal compound in the optically anisotropic layer 14 can be controlled more strictly by providing the alignment film 22.
Each member used in the transfer film 300 is as described above.

In this embodiment, the method for satisfying the above-described peel strength relationship is not particularly limited, and a known method can be adopted. For example, as described later, when forming the alignment film, a method of forming the alignment film using an alignment agent having a polymerizable group and then performing the above-described steps 2 to 3 can be mentioned. According to this method, when the optically anisotropic layer is formed on the alignment film, the polymerizable group of the alignment agent remaining on the alignment film surface reacts with the polymerizable group of the liquid crystal compound to form a chemical bond. As a result, the adhesion between the alignment film and the optically anisotropic layer is further improved. That is, the peel strength at the interface between the alignment film and the optically anisotropic layer and the peel strength at the interface between the optically anisotropic layer and the resin layer are relative to the peel strength between the peelable support and the alignment film. Can be increased.
In addition, as described above, there is also a method in which the peel strength between the peelable support and the alignment film is reduced by treating the peelable support surface with a known release agent.

The alignment film in this embodiment contains polyvinyl alcohol having a polymerizable group in the molecule (hereinafter also referred to as “polymerizable PVA”) in order to ensure adhesion between the alignment film and the optically anisotropic layer. It is preferably formed from the composition. By aligning a liquid crystal compound having a polymerizable group on an alignment film containing polymerizable PVA, fixing the alignment state by polymerization, and forming an optically anisotropic layer or the like, an optically anisotropic layer and an alignment film A chemical bond is formed at the interface between the two and adhesion is improved. The polymerizable PVA includes PVA containing a repeating unit having a polymerizable group, and PVA obtained by reacting a compound having a polymerizable group with PVA or modified PVA.
The polymerizable group possessed by the polymerizable PVA is preferably selected according to the type of the polymerizable group contained in the liquid crystal compound. When the polymerizable group contained in the liquid crystal compound is an unsaturated double bond group, the polymerizable group contained in the polymerizable PVA is also preferably an unsaturated double bond group.
The polymerizable PVA preferably has an average degree of saponification of 95% or less, and more preferably 90 mol% or less. The average saponification degree of the polymerizable PVA is preferably about 70% or more.
The average degree of polymerization of the polymerizable PVA is preferably 800 or less, more preferably 600 or less, and particularly preferably 400 or less.

  When the alignment film is formed from a composition containing polymerizable PVA, it is preferable to use a cellulose acylate film (unsaponified cellulose acylate film) that has not been saponified as the peelable support. By using this cellulose acylate film, the peel strength at the interface between the peelable support and the alignment film is further lowered, and the peelable support is more easily separated.

  Hereinafter, the present invention will be described in more detail based on examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the following examples.

<Example 1>
(Manufacture of peelable support)
A rubbing treatment was applied to PET (polyethylene terephthalate film, thickness 75 μm) manufactured by Fuji Film to prepare a peelable support 1.

(Manufacture of optically anisotropic layer)
A coating liquid for optically anisotropic layer (composition A1) described later was applied onto the rubbing treated surface of the peelable support 1 using a bar coater. Next, the film surface is aged at 60 ° C. for 60 seconds, and irradiated with ultraviolet rays using an air-cooled metal halide lamp (produced by Eye Graphics Co., Ltd.) of 20 mW / cm ^{2 in} the air to fix the orientation state. As a result, an optically anisotropic layer A1 was formed. In the formed optically anisotropic layer A1, the rod-like liquid crystal compound was horizontally aligned with the slow axis direction parallel to the rubbing direction. The in-plane retardation (referred to as ReA1 (450), ReA1 (550), and ReA1 (650), respectively) of the optically anisotropic layer A1 when measured at wavelengths of 450 nm, 550 nm, and 650 nm was as follows. The thickness of the optically anisotropic layer A1 was 0.98 μm.
ReA1 (450): 155.4 nm
ReA1 (550): 137.5 nm
ReA1 (650): 132 nm
ReA1 (450) / ReA1 (650): 1.18
──────────────────────────────────
Composition of coating liquid for optically anisotropic layer (Composition A1)
──────────────────────────────────
Rod-like liquid crystalline compound 1 80 parts by weight Rod-like liquid crystalline compound 2 20 parts by weight Photopolymerization initiator 3.0 parts by weight (Irgacure 907, manufactured by Ciba Specialty Chemicals)
Sensitizer (Kayacure-DETX, Nippon Kayaku Co., Ltd.) 1.0 part by mass Fluorine-containing compound 0.8 part by weight Methyl ethyl ketone 400 parts by weight ───────────────── ─────────────────

(Manufacture of resin layer (part 1))
A composition B1, which will be described later, was applied onto the optically anisotropic layer A1 using a wire bar, dried at 60 ° C. for 150 seconds, and then air-cooled at 160 W / cm at an oxygen concentration of about 0.1% under a nitrogen purge. Using a metal halide lamp (manufactured by Eye Graphics Co., Ltd.), the coating layer is cured by irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 300 mJ / cm ² , and a resin layer having a thickness of 5 μm (non-thermoplastic) Acrylic resin layer) was formed to obtain a transfer film.

-------------------------------------------------- ----------------
(Composition B1)
-------------------------------------------------- ----------------
・ DPHA (A-DPH manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass ・ A-600 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass ・ IRGACURE819 (manufactured by BASF) 2 parts by mass ・ 0.03 parts by mass of fluorine compound

・ Methyl ethyl ketone 159.6 parts by mass
-------------------------------------------------- ---------------

<Example 2>
The amount of DPHA used in composition B1 was changed from 50 parts by weight to 70 parts by weight, the amount of A-600 used was changed from 50 parts by weight to 30 parts by weight, and the thickness of the resin layer was changed from 5 μm to 10 μm. A transfer film was produced according to the same procedure as in Example 1 except for the above.

<Example 3>
A-DCP (manufactured by Shin-Nakamura Chemical Co., Ltd., 66 parts by mass) is used instead of DPHA (50 parts by mass) in composition B1, and the amount of A-600 used is changed from 50 parts by mass to 34 parts by mass. A transfer film was produced according to the same procedure as in Example 1 except that the thickness of the resin layer was changed from 5 μm to 10 μm.

<Example 4>
A-DCP (84 parts by mass) is used instead of DPHA (50 parts by mass) in composition B1, and the amount of A-600 used is changed from 50 parts by mass to 16 parts by mass, and the thickness of the resin layer is 5 μm. A transfer film was produced according to the same procedure as in Example 1 except that the thickness was changed from 10 to 10 μm.

<Example 5>
Instead of DPHA (50 parts by mass) in composition B1, A-DCP (88 parts by mass) is used, the amount of A-600 used is changed from 50 parts by mass to 12 parts by mass, and the thickness of the resin layer is 5 μm. A transfer film was produced according to the same procedure as in Example 1 except that the thickness was changed to 15 μm.

<Example 6>
Instead of DPHA (50 parts by mass) in composition B1, A-DCP (90 parts by mass) is used, the amount of A-600 used is changed from 50 parts by mass to 10 parts by mass, and the thickness of the resin layer is 5 μm. A transfer film was produced according to the same procedure as in Example 1 except that the thickness was changed from 20 to 20 μm.

<Example 7>
According to the same procedure as in Example 1, except that the peelable support 2 obtained by the procedure described later was used instead of the peelable support using PET (polyethylene terephthalate film, thickness 75 μm) manufactured by Fuji Film, A transfer film was produced.

(Manufacture of peelable support 2)
<Preparation of transparent support A>
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acylate solution A.
──────────────────────────────────
Composition of Cellulose Acylate Solution A───────────────────────────────────
Cellulose acetate having a substitution degree of 2.86 100 parts by weight Triphenyl phosphate (plasticizer) 7.8 parts by weight Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by weight Methylene chloride (first solvent) 300 parts by weight Methanol (second solvent) ) 54 parts by mass 1-butanol 11 parts by mass ──────────────────────────────────

The following composition was charged into another mixing tank, stirred while heating to dissolve each component, and an additive solution B was prepared.
──────────────────────────────────
Composition of additive solution B ──────────────────────────────────
The following compound B1 (Re reducing agent) 40 parts by mass The following compound B2 (wavelength dispersion controlling agent) 4 parts by mass Methylene chloride (first solvent) 80 parts by mass Methanol (second solvent) 20 parts by mass ──────── ──────────────────────────

<Production of cellulose acetate transparent support>
A dope was prepared by adding 40 parts by mass of the additive solution B to 477 parts by mass of the cellulose acylate solution A and stirring sufficiently. The dope was cast from a casting port onto a drum cooled to 0 ° C. The film is peeled off at a solvent content of 70% by mass, and both ends in the width direction of the film are fixed with a pin tenter (the pin tenter described in FIG. 3 of JP-A-4-1009), and the solvent content is 3 to 5% by mass. Then, it was dried while maintaining an interval at which the stretching ratio in the transverse direction (direction perpendicular to the machine direction) was 3%. Then, it dried further by conveying between the rolls of the heat processing apparatus, and produced the 60-micrometer-thick cellulose acetate transparent support body A. Transparent support A did not contain an ultraviolet absorber, Re (550) was 0 nm, and Rth (550) was 12.3 nm. Rth (550) is a retardation in the thickness direction of the transparent support A measured at a wavelength of 550 nm.

<< Alkaline saponification treatment >>
After passing the transparent support A through a dielectric heating roll having a temperature of 60 ° C. and raising the film surface temperature to 40 ° C., an alkali solution having the composition shown below is applied to one side of the film using a bar coater. It was applied at an amount of 14 ml / m ² , heated to 110 ° C., and conveyed for 10 seconds under a steam far infrared heater manufactured by Noritake Company Limited. Subsequently, 3 ml / m ^{2 of} pure water was applied using the same bar coater. Next, washing with a fountain coater and draining with an air knife were repeated three times, followed by transporting to a drying zone at 70 ° C. for 10 seconds and drying to prepare an alkali saponified cellulose acetate transparent support A.

──────────────────────────────────
Composition of alkaline solution (parts by mass)
──────────────────────────────────
Potassium hydroxide 4.7 parts by weight Water 15.8 parts by weight Isopropanol 63.7 parts by weight Surfactant SF-1: C ₁₄ H ₂₉ O (CH ₂ CH ₂ O) ₂₀ H 1.0 part by weight Propylene glycol 14. 8 parts by mass ──────────────────────────────────

<Preparation of alignment film>
On the surface of the transparent support A subjected to the saponification treatment, an alignment film forming coating solution 1 having the following composition was continuously applied with a # 8 wire bar. The alignment film was formed by drying with warm air of 60 ° C. for 60 seconds and further with warm air of 100 ° C. for 120 seconds. The surface of the prepared alignment film was continuously rubbed in the longitudinal direction of the transparent support A to obtain a peelable support 2.
──────────────────────────────────
Composition of coating liquid 1 for alignment film formation ──────────────────────────────────
Polymer material for alignment film 4.0 parts by mass (PVA103, Kuraray Co., Ltd. polyvinyl alcohol)
Methanol 36 parts by mass Water 60 parts by mass──────────────────────────────────

<Example 8>
A transfer film was produced according to the same procedure as in Example 7 except that the peelable support 3 obtained by the procedure described later was used instead of the peelable support 2.

(Manufacture of peelable support 3)
The peelable support 3 was produced according to the same procedure as the production of the peelable support 2 except that the alignment film was produced as follows without subjecting the transparent support A to alkali saponification treatment.

<< Preparation of alignment film >>
The transparent support A was coated with 28 mL / m ^{2 of} an alignment film forming coating solution 2 having the following composition using a # 16 wire bar coater. Then, it was dried for 60 seconds with warm air of 60 ° C. and for 150 seconds with warm air of 90 ° C.
[Alignment film forming coating solution 2]
-Modified polyvinyl alcohol represented by the following general formula (VI) 10 parts by mass-371 parts by weight of water-119 parts by weight of methanol-0.5 parts by weight of glutaraldehyde (crosslinking agent)-Citric acid ester (AS3 manufactured by Sankyo Chemical Co., Ltd.) ) 0.175 parts by mass / photopolymerization initiator (Irgacure 2959, manufactured by BASF) 2.0 parts by mass

<Example 9>
The procedure for producing the optically anisotropic layer was changed to the following (Manufacture of optically anisotropic layer (2)), and the thickness of the resin layer was changed from 5 μm to 10 μm. A transfer film was produced.

(Manufacture of optically anisotropic layer (2))
The alignment film surface of Example 7 was rubbed continuously in the longitudinal direction of the transparent support A. The following coating liquid for optically anisotropic layer (composition A2) was applied on the rubbing surface using a bar coater. Next, after aging at a film surface temperature of 115 ° C. for 90 seconds, the film was cooled to 80 ° C. and irradiated with ultraviolet rays using an air-cooled metal halide lamp (produced by Eye Graphics Co., Ltd.) of 20 mW / cm ² in air. The optically anisotropic layer A2 was formed by irradiating to cm ² and fixing the alignment state. The in-plane retardation of the optically anisotropic layer A2 (respectively referred to as ReA2 (450), ReA2 (550), and ReA2 (650)) when measured at wavelengths of 450 nm, 550 nm, and 650 nm was as follows. The thickness of the optically anisotropic layer A2 was 0.85 μm.
ReA2 (450): 149.8 nm
ReA2 (550): 137.5 nm
ReA2 (650): 132 nm
ReA2 (450) / ReA2 (650): 1.14

──────────────────────────────────
Composition of coating liquid for optically anisotropic layer (Composition A2)
──────────────────────────────────
Discotic liquid crystal E-1 80 parts by mass Discotic liquid crystal 2 20 parts by mass alignment film interface alignment agent 1 0.55 parts by mass alignment film interface alignment agent 2 0.05 parts by mass fluorinated compound 0.1 parts by mass modified trimethylolpropane Triacrylate 10 parts by weight Photopolymerization initiator 3.0 parts by weight (Irgacure 907, manufactured by Ciba Specialty Chemicals)
Methyl ethyl ketone 200 parts by mass ───────────────────────────────────

<Example 10>
The manufacturing procedure of the optically anisotropic layer was changed to the following (Manufacturing of the optically anisotropic layer (part 3)) and the thickness of the resin layer was changed from 5 μm to 10 μm. A transfer film was produced.

(Manufacture of optically anisotropic layer (3))
The alignment film surface of Example 7 was continuously rubbed in the direction of 45 ° to the left with respect to the longitudinal direction of the transparent support A. The following coating liquid for optically anisotropic layer (composition A3) was applied on the rubbing surface using a bar coater. Next, after aging at a film surface temperature of 115 ° C. for 90 seconds, the film was cooled to 80 ° C. and irradiated with ultraviolet rays using an air-cooled metal halide lamp (produced by Eye Graphics Co., Ltd.) of 20 mW / cm ² in air. The optically anisotropic layer A3 was formed by irradiating to cm ² and fixing the alignment state. In the formed optically anisotropic layer A3, the discotic liquid crystal was vertically aligned with the slow axis direction orthogonal to the rubbing direction. The in-plane retardation of the optically anisotropic layer A3 (respectively referred to as ReA3 (450), ReA3 (550), and ReA3 (650)) when measured at wavelengths of 450 nm, 550 nm, and 650 nm was as follows. The optical anisotropic layer A3 had a thickness of 2.5 μm.
ReA3 (450): 273 nm
ReA3 (550): 250 nm
ReA3 (650): 240 nm
ReA3 (450) / ReA3 (650): 1.14

──────────────────────────────────
Composition of coating liquid for optically anisotropic layer (Composition A3)
──────────────────────────────────
Discotic liquid crystal E-1 80 parts by mass Discotic liquid crystal 2 20 parts by mass alignment film interface alignment agent 1 0.55 parts by mass alignment film interface alignment agent 2 0.05 parts by mass fluorinated compound 0.1 parts by mass modified trimethylolpropane Triacrylate 10 parts by weight Photopolymerization initiator 3.0 parts by weight (Irgacure 907, manufactured by Ciba Specialty Chemicals)
Interlayer orientation agent 0.6 parts by weight Methyl ethyl ketone 180 parts by weight cyclohexanone 20 parts by weight ─────────────────────────────────

The surface of the optically anisotropic layer A3 was continuously rubbed in a direction perpendicular to the slow axis of the optically anisotropic layer A3. The following coating liquid for optically anisotropic layer (composition A4) was applied on the rubbing surface using a bar coater. Next, the film surface is aged at 60 ° C. for 60 seconds, and irradiated with ultraviolet rays using an air-cooled metal halide lamp (produced by Eye Graphics Co., Ltd.) of 20 mW / cm ^{2 in} the air to fix the orientation state. As a result, an optically anisotropic layer A4 was formed. In the formed optically anisotropic layer A4, the rod-like liquid crystal was horizontally aligned with the slow axis direction parallel to the rubbing direction. In-plane retardation of the optically anisotropic layer A4 (respectively referred to as ReA4 (450), ReA4 (550), and ReA4 (650)) when measured at wavelengths of 450 nm, 550 nm, and 650 nm was as follows. The thickness of the optically anisotropic layer A4 was 1.0 μm.
ReA4 (450): 141 nm
ReA4 (550): 125 nm
ReA4 (650): 120 nm
ReA4 (450) / ReA4 (650): 1.18
In addition, ReA3 (550) of the optically anisotropic layer A3 and ReA4 (550) of the optically anisotropic layer A4 have a relationship of ReA3 (550)> ReA4 (550).

──────────────────────────────────
Composition of coating liquid for optically anisotropic layer (Composition A4)
──────────────────────────────────
Rod-like liquid crystalline compound 1 90 parts by weight Rod-like liquid crystalline compound 2 10 parts by weight Photopolymerization initiator 3.0 parts by weight (Irgacure 907, manufactured by Ciba Specialty Chemicals)
Sensitizer (Kayacure-DETX, Nippon Kayaku Co., Ltd.) 1.0 part by mass Fluorine-containing compound 0.5 part by weight Methyl ethyl ketone 400 parts by weight ───────────────── ─────────────────

<Comparative Example 1>
Instead of preparing the alignment film using the alignment film forming coating solution 1, the alignment film coating liquid AL-1 described in paragraph 0157 of Patent Document 2 (Japanese Patent Application Laid-Open No. 2013-7887) is used. Instead of preparing an alignment film (thickness 0.6 μm) according to the method described in paragraph 0163 of No. 2 and using the coating solution for optically anisotropic layer (composition A1), an optically anisotropic layer is prepared. Using the coating liquid LC-1 for optically anisotropic layer described in paragraphs 0158 to 0159 of Document 2, an optically anisotropic layer (thickness: 4.5 μm) is prepared according to the method described in Paragraph 0163 of Patent Document 2. Then, instead of producing the non-thermoplastic acrylic resin layer, the additive layer coating solution described in paragraphs 0160 to 0161 of Patent Document 2 is used, and the additive layer is prepared according to the method described in Paragraph 0163 of Patent Document 2. (Thickness 0.9 μm) Following a procedure analogous to 施例 7 was prepared transfer film.
The additive layer does not correspond to the non-thermoplastic acrylic resin layer of the present invention, and the relationship between the thickness of the additive layer and the optically anisotropic layer does not satisfy the relationship of the present invention.

<Comparative Example 2>
Transfer according to the same procedure as in Example 1 except that the amount of DPHA used in composition B1 was changed from 50 parts by weight to 95 parts by weight, and the amount of A-600 used was changed from 50 parts by weight to 5 parts by weight. A film was produced.
In addition, content of the polyoxyalkylene chain in the resin layer obtained in Comparative Example 2 was 4% by mass.

<Comparative Example 3>
Transfer according to the same procedure as in Example 1 except that DPHA in composition B1 was changed from 50 parts by weight to 10 parts by weight and A-600 was changed from 50 parts by weight to 90 parts by weight. A film was produced.
In addition, content of the polyoxyalkylene chain in the resin layer obtained in Comparative Example 3 was 72% by mass.

<Peelability evaluation>
Regarding the transfer films obtained in the above examples, the peelability of the optical film was evaluated according to the following procedure.
The end of the peelable support in the transfer film (vertical: 20 cm × width: 10 cm) was gripped and pulled away from the optical film to separate the peelable support from the optical film.
The case where the peelable support can be peeled cleanly is “OK”, and the case where the peelable support cannot be peeled or the case where a part of the peelable support is not peeled is designated “NG”.
As will be described later, all the transfer films obtained in the above examples were “OK”. From this result, it was confirmed that the peel strength at the interface between the peelable support and the optical film is smaller than the peel strength between the optically anisotropic layer and the non-thermoplastic acrylic resin layer.

<Self-supporting evaluation>
Regarding the transfer films obtained in the above examples, the self-supporting property of the optical film was evaluated according to the following procedure.
The end of the peelable support in the transfer film (vertical: 20 cm x width: 10 cm) is fixed, and the vicinity of the end corner of the optical film is lifted from the peelable support using cellophane tape. The whole was peeled off from the peelable support and separated. Thereafter, the optical film was placed on a flat table, and the shape was evaluated according to the following evaluation criteria. In practice, it is preferably not 1.
1. 1. The optical film broke during peeling. 2. The optical film did not break, but the curl was large and became cylindrical. The optical film did not break, but the curl was moderate (the rise of the end of the optical film from a horizontal base was more than 1 cm)
4). The optical film did not break, but some curling was observed, but it was small (up to 1 cm at the end of the optical film from the horizontal base)
5). The optical film did not break or curl

<Bending test A and B>
The above-described bending test A was performed using the transfer films obtained in the examples and comparative examples. The results are summarized in Table 1.
The optical film was peeled off from the transfer films obtained in the above examples and comparative examples, and the bending test B described above was performed. The results are summarized in Table 1.

“Polyoxyalkylene chain content (% by mass)” in Table 1 indicates the content of the polyoxyalkylene chain in the non-thermoplastic acrylic resin layer, and the content was calculated from the charged amount of the monomer used. .
In addition, the resin layers obtained in the examples had a melting point of over 200 ° C. and exhibited non-thermoplasticity.

As shown in Table 1, the optical film in the transfer film of the present invention exhibited excellent self-supporting properties.
In particular, as can be seen from a comparison between Example 5 and other examples, it was confirmed that the self-supporting property was more excellent when the content of the polyoxyalkylene chain was 12 to 60% by mass.
On the other hand, in the comparative example 1 applicable to the aspect described in patent document 2, the self-supporting property of the optical film was inferior, and could not be used as a transfer film. Further, as shown in Comparative Examples 2 and 3, even when the content of the polyoxyalkylene chain was not within the predetermined range, the optical film had poor self-supporting properties and could not be used as a transfer film.

10, 100, 200, 300 Transfer film 12, 120 Peelable support 14, 140 Optical anisotropic layer 16 Non-thermoplastic acrylic resin layer 18, 180 Optical film 20 Base material 22 Orientation film 140a First retardation region 140b First Two phase difference regions 142a, 142b In-plane slow axis

Claims (6)

A transfer film comprising a peelable support and an optical film that is releasably laminated on the peelable support,
The optical film includes an optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The acrylic resin in the non-thermoplastic acrylic resin layer has a polyoxyalkylene chain,
The content of the polyoxyalkylene chain is 8 to 60% by mass with respect to the total mass of the non-thermoplastic acrylic resin layer,
The non-thermoplastic acrylic resin layer has a thickness of 5 to 25 μm, the optically anisotropic layer has a thickness of 0.1 to 10 μm, and the non-thermoplastic acrylic resin layer has a thickness of the optically anisotropic layer. Transfer film thicker than   The transfer film according to claim 1, wherein the content of the polyoxyalkylene chain is 12 to 60 mass% with respect to the total mass of the non-thermoplastic acrylic resin layer. A transfer film comprising a peelable support and an optical film that is releasably laminated on the peelable support,
The optical film includes an optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The non-thermoplastic acrylic resin layer has a thickness of 5 to 25 μm, the optically anisotropic layer has a thickness of 0.1 to 10 μm, and the non-thermoplastic acrylic resin layer has a thickness of the optically anisotropic layer. Thicker than
The transfer film in which the number of bending times of the optical film obtained from the following bending test A is 10 or more.
(Bending test A: The transfer film was cut to 10 cm × 10 cm, and the transfer film cut on a horizontal base was placed so that the peelable support was directed to the horizontal base, and the transfer film was The optical film is peeled from the peelable support member up to half of the length from one side to the other side, and the peeled portion of the optical film is returned to the horizontal with respect to the peelable support member, and then the peeled portion. The tip is lifted until the peeled portion is perpendicular to the peelable support, and the process of returning the peeled portion to the original position is repeated, and the number of bending processes in which the optical film is cracked is N. (N-1) is the number of bendings.) An optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The acrylic resin in the non-thermoplastic acrylic resin layer has a polyoxyalkylene chain,
The content of the polyoxyalkylene chain is 8 to 60% by mass with respect to the total mass of the non-thermoplastic acrylic resin layer,
The non-thermoplastic acrylic resin layer has a thickness of 5 to 25 μm, the optically anisotropic layer has a thickness of 0.1 to 10 μm, and the non-thermoplastic acrylic resin layer has a thickness of the optically anisotropic layer. An optical film that is thicker than.   The optical film of Claim 4 whose content of the said polyoxyalkylene chain is 12-60 mass% with respect to the non-thermoplastic acrylic resin layer total mass. An optically anisotropic layer containing a liquid crystal compound, and a non-thermoplastic acrylic resin layer adjacent to the optically anisotropic layer,
The non-thermoplastic acrylic resin layer has a thickness of 5 to 25 μm, the optically anisotropic layer has a thickness of 0.1 to 10 μm, and the non-thermoplastic acrylic resin layer has a thickness of the optically anisotropic layer. Thicker than
The optical film whose bending frequency calculated | required from the following bending tests B is 10 times or more.
(Bending test B: After cutting the optical film into 10 cm × 10 cm and placing the optical film cut on a horizontal base, up to half the length from one side of the optical film to the other side Repeat the bending operation to lift one side of the optical film until the optical film part peeled from the table is perpendicular to the table, and then return to the original film. (The number of bending operations in which cracks occur is N, and (N-1) is the number of bending times.)