JP6388053B2 - Optical film transfer body, optical film, optical film transfer body manufacturing method, optical film manufacturing method - Google Patents

Description

  The present invention relates to an optical film in which, for example, a quarter wavelength plate is formed by stacking a half wavelength retardation layer and a quarter wavelength retardation layer.

  Conventionally, regarding an image display device, a method has been proposed in which an optical film made of a circularly polarizing plate is arranged on the panel surface (viewer side surface) of an image display panel, and reflection of extraneous light is reduced by this optical film. Here, this optical film is composed of a laminate of a linear polarizing plate and a quarter-wave plate, and converts external light directed to the panel surface of the image display panel into linearly-polarized light by the linear polarizing plate, followed by a quarter-wave plate. Convert to circularly polarized light. Here, the extraneous light by the circularly polarized light is reflected by the surface of the image display panel or the like, but the rotation direction of the polarization plane is reversed during the reflection. As a result, contrary to the arrival time, this reflected light is converted into linearly polarized light in the direction shielded by the linear polarizing plate by the quarter wavelength plate, and then shielded by the subsequent linear polarizing plate. Outgoing emission is significantly suppressed.

  With regard to this optical film, Patent Document 1 and the like include a 1/2 wavelength phase difference layer that imparts a phase difference of ½ wavelength to transmitted light, and a 1 / wavelength that imparts a phase difference of ¼ wavelength to transmitted light. A method has been proposed in which a quarter-wave plate is formed by laminating four-wavelength retardation layers to use a liquid crystal material having a positive dispersion characteristic so that the quarter-wave plate functions with a reverse dispersion characteristic. Here, the reverse dispersion characteristic is a wavelength dispersion characteristic in which the phase difference in transmitted light is smaller as the wavelength is shorter.

  The half-wave retardation layer, the quarter-wave retardation layer, and the like can be created by solidifying (curing) the liquid crystal material in a state where the liquid crystal material is aligned by the alignment regulating force of the alignment film. . More specifically, this type of retardation layer is formed by laminating a polymerizable liquid crystal monomer on an alignment film, raising the temperature to the phase transition point, and then polymerizing by ultraviolet irradiation or the like to fix the alignment state of the liquid crystal. It is produced by. In addition, the alignment film can be created by transferring the fine uneven shape created in the shaping mold by, for example, a shaping process using the shaping mold, or by a so-called photo-alignment technique. can do.

  By the way, after the ½ wavelength phase difference layer and the ¼ wavelength phase difference layer are individually formed and then bonded together by an adhesive layer, a laminate of the ½ wavelength phase difference layer and the ¼ wavelength phase difference layer is obtained. Thus, it is considered that a quarter wavelength plate can be produced. At this time, it is considered that the entire thickness can be reduced by directly bonding the ½ wavelength retardation layer and the ¼ wavelength retardation layer with an adhesive layer made of an adhesive.

  Thus, when producing a laminated body, it is calculated | required to avoid the damage | wound of a phase difference layer effectively.

JP-A-10-68816 JP 2000-284126 A

  The present invention has been made in view of such circumstances, and in a configuration in which an optical film is produced by laminating a retardation layer with an adhesive layer or the like, scratches on the retardation layer or the like can be effectively avoided. Like that.

  In order to solve the above-mentioned problems, the present inventor has made extensive studies, and by laminating a laminate of a ½ wavelength retardation layer and a ¼ wavelength retardation layer on a linear polarizing plate by a transfer method, The idea of effectively preventing the retardation layer from being damaged by setting the support substrate to be removed by application of the transfer method was reached, and the present invention was completed.

(1) A transfer body for an optical film comprising a support substrate and a transfer layer,
The transfer layer is
A quarter-wave retardation layer that imparts at least a quarter-wave phase difference to transmitted light; a half-wave retardation layer that imparts a half-wave phase difference to transmitted light; An adhesive layer that bonds the four-wavelength retardation layer and the ½-wavelength retardation layer;
The outermost layer has a higher hardness than the support substrate.

  According to (1), damage due to lamination occurs on the support substrate side, and damage to the outermost layer can be prevented, and as a result, damage to the retardation layer and the like is effectively avoided. be able to.

(2) In (1),
It is a roll body which made the said support base material inside.

  According to (2), it is possible to prevent the outermost layer from being damaged with respect to the stacking that can be wound by the roll, and as a result, it is possible to effectively avoid the scratch of the retardation layer and the like.

(3) In (1) or (2),
The transfer layer is
From the support substrate side, an alignment film for a quarter wavelength retardation layer, the quarter wavelength retardation layer, the adhesive layer, and the half wavelength retardation layer according to the quarter wavelength retardation layer. , An alignment film for a ½ wavelength retardation layer according to the ½ wavelength retardation layer,
The outermost layer is the alignment film for a ½ wavelength retardation layer.

  According to (3), the transfer layer includes the alignment film for 1/4 wavelength retardation layer, the 1/4 wavelength retardation layer, the adhesive layer, the 1/2 wavelength retardation layer, and the alignment film for 1/2 wavelength retardation layer. Can be effectively avoided from being scratched on the alignment film for a half-wave retardation layer.

(4) In (1) or (2),
The transfer layer is
From the support substrate side, the 1/4 wavelength retardation layer, the adhesive layer, the 1/2 wavelength retardation layer,
The outermost layer is the half-wave retardation layer.

  According to (4), when the transfer layer is constituted by the quarter-wave retardation layer, the adhesive layer, and the half-wave retardation layer, the scratch of the half-wave retardation layer is effectively avoided. Can do.

(5) In (1), (2), (3), or (4),
The hardness is a pencil hardness H.

  According to (5), scratches such as the retardation layer can be effectively avoided with a simple configuration.

  (6) The transfer layer of the transfer member for an optical film described in (1), (2), (3), (4), or (5) is bonded to a linear polarizing plate to constitute an optical film.

  According to (6), an optical film can be comprised with the phase difference layer etc. which avoid a damage | wound effectively.

(7) A method for producing a transfer body for an optical film comprising a support substrate and a transfer layer,
1/4 wavelength retardation layer is prepared on the support substrate, and a laminate of the support substrate and 1/4 wavelength retardation layer alignment film is prepared. A step of preparing an alignment film for the retardation layer;
A quarter-wave retardation layer is prepared in a laminate of the support substrate and the quarter-wave retardation layer alignment film, and the support substrate, the quarter-wave retardation layer alignment film, A quarter-wave retardation layer producing step of producing a laminate of quarter-wave retardation layers;
An alignment film for a ½ wavelength retardation layer is prepared on a substrate for a ½ wavelength retardation layer, and the substrate for the ½ wavelength retardation layer, the ½ wavelength retardation layer is formed. An alignment film preparation step for a half-wave retardation layer for preparing a laminate of alignment films for use;
A half-wave retardation layer was prepared on the laminate of the base material for the half-wave retardation layer and the alignment film for the half-wave retardation layer. A half-wave retardation layer producing step of producing a laminate of a substrate, a half-wave retardation layer alignment film, and a half-wave retardation layer;
Laminating the ¼ wavelength retardation layer and the ½ wavelength retardation layer, a laminate of the support substrate, the ¼ wavelength retardation layer alignment layer, and a ¼ wavelength retardation layer; A bonding step of integrating the base material for the half-wavelength retardation layer, the alignment film for the half-wavelength retardation layer, and the laminate of the half-wavelength retardation layer;
From the laminate integrated by the bonding step, the base material for the ½ wavelength retardation layer, or the base material for the ½ wavelength retardation layer and the alignment film for the ½ wavelength retardation layer A peeling process for peeling the laminate,
The ½ wavelength retardation layer preparation step or the ½ wavelength retardation layer preparation step includes:
The alignment film for 1/2 wavelength retardation layer or the 1/2 wavelength retardation layer is prepared so that the hardness of the outermost layer of the transfer layer is increased with respect to the support substrate.

  According to (7), damage due to lamination occurs on the support substrate side, and damage to the alignment film for 1/2 wavelength phase difference layer or 1/2 wavelength phase difference layer which is the outermost layer is prevented. can do.

  (8) From the optical film transfer body described in (7), the transfer layer is bonded to a linearly polarizing plate and integrated to prepare an optical film.

  According to (8), an optical film can be comprised with the phase difference layer etc. which avoid a damage | wound effectively.

  The present invention can effectively prevent damage to the retardation layer or the like in a configuration in which the retardation layer is bonded with an adhesive layer or the like to produce an optical film.

It is sectional drawing which shows the image display apparatus which concerns on 1st Embodiment of this invention. It is a figure where it uses for description of the optical film applied to the image display apparatus of FIG. It is sectional drawing which shows the transfer film which concerns on the optical film of FIG. It is a figure where it uses for description of the manufacturing process of the transfer film of FIG. It is a figure where it uses for description of the manufacturing process of the optical film by the transfer film of FIG. It is a figure where it uses for description of the process of the continuation of FIG. It is a figure where it uses for description of the manufacturing process of FIG. It is a figure with which it uses for description of the continuation of FIG. It is sectional drawing which shows the image display apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the transfer film which concerns on the image display apparatus of FIG.

[First Embodiment]
[Optical film and image display device]
FIG. 1 is a diagram showing an image display apparatus according to the first embodiment of the present invention. In the image display device 11, an optical film 13 is disposed on the panel surface (viewer side surface) of the image display panel 12. Here, the image display panel 12 is an organic EL panel, for example, and displays a desired color image. Note that the image display panel 12 is not limited to the organic EL panel, and various image display panels such as a liquid crystal display panel can be widely applied.

  The optical film 13 is an optical film that suppresses reflection of extraneous light arriving at the image display panel 12 by the function of a circularly polarizing plate. For this reason, the optical film 13 is configured by laminating a linear polarizing plate 15 and a quarter-wave plate 16. The optical film 13 is peeled off a separator film (not shown) to expose the pressure-sensitive adhesive 14 with a pressure-sensitive adhesive, and is then attached and held on the panel surface of the image display panel 12 by the pressure-sensitive adhesive layer 14. Instead of the pressure-sensitive adhesive, the optical film 13 may be arranged by various adhesives such as an ultraviolet curable resin and an adhesive. The linear polarizing plate 15 and the quarter wavelength plate 16 are integrated with each other through the adhesive layer 17. Here, although various adhesives such as an ultraviolet curable resin, a thermosetting resin, and a pressure sensitive adhesive can be widely applied, the adhesive layer 17 is made of an ultraviolet curable resin from the viewpoint of reducing the overall thickness. In this case, it can be formed with a thickness of about 1 μm.

  The quarter wavelength plate 16 includes a quarter wavelength retardation layer 18 that imparts a phase difference of ¼ wavelength to transmitted light, and a ½ wavelength that imparts a phase difference of ½ wavelength to the transmitted light. It is comprised by the laminated body which bonded together the phase difference layer 19 with the contact bonding layer 20. FIG. Thereby, the optical film 13 sufficiently suppresses reflection of extraneous light in a wide wavelength band used for displaying a color image.

  The quarter-wave plate 16 is used for the production of the quarter-wave retardation layer 18 and the half-wave retardation layer 19. An alignment film 23 is provided on each of the image display panel 12 side and the linearly polarizing plate 15 side, whereby a transfer method is applied to produce an optical film 13 to reduce the overall thickness, and a 1/4 wavelength phase difference. The layer alignment film 22 and the ½ wavelength retardation layer alignment film 23 function as a protective layer to reduce damage to the ¼ wavelength retardation layer 18 and the ½ wavelength retardation layer 19.

  Accordingly, in the image display device 11, the ¼ wavelength phase difference layer 18, the ½ wavelength phase difference layer 19, and the linear polarizing plate 15 are sequentially arranged from the display screen side of the image display panel 12. In addition, as shown in FIG. 2, the slow axes (indicated by arrows respectively) of the ½ wavelength phase difference layer 19 and the ¼ wavelength phase difference layer 18 with respect to the transmission axis of the linearly polarizing plate 15 indicated by arrows. Are arranged so as to form angles of 15 degrees and 73 degrees counterclockwise, respectively.

  The quarter-wave retardation layer alignment film 22 and the half-wave retardation layer alignment film 23 are formed by forming a fine uneven shape on the surface, and 1 / The liquid crystal material according to the four-wavelength phase difference layer 18 and the half-wavelength phase difference layer 19 is aligned. The quarter-wave retardation layer alignment film 22 and the half-wave retardation layer alignment film 23 have a 10-point average roughness (Rz) of 10 nm to 45 nm, and an average surface roughness. (Ra) is 1 nm or more and 4 nm or less. As a result, the quarter-wave retardation layer alignment film 22 and the half-wave retardation layer alignment film 23 are disposed between the corresponding quarter-wave retardation layer 18 and the half-wave retardation layer 19. Sufficient adhesion strength can be secured, and variations in the quarter-wave retardation layer 18 and the half-wave retardation layer 19 related to so-called black luminance can be sufficiently reduced.

  In this embodiment, the quarter-wave retardation layer alignment film 22 and the half-wave retardation layer alignment film 23 are formed after the forming resin layer for forming a fine concavo-convex shape is formed. A fine concavo-convex shape is created and formed on the surface of this shaping resin layer by a shaping treatment. In this embodiment, an ultraviolet curable resin is applied to the shaping resin, and an acrylic ultraviolet curable resin is used. However, the present invention is not limited to this, and various resins used for the shaping process can be widely applied. it can.

  In addition, the fine uneven shape relating to the alignment film 23 for 1/2 wavelength retardation layer and the alignment film 22 for 1/4 wavelength retardation layer is formed by a line (line) uneven shape extending in one direction. The direction extending in one direction is formed so as to form an angle of 15 degrees and 73 degrees counterclockwise with respect to the transmission axis of the linear polarizing plate 15, respectively.

  The quarter-wave retardation layer 18 and the half-wave retardation layer 19 are made of a liquid crystal material that is solidified (cured) while maintaining refractive index anisotropy by the orientation regulating force of the corresponding orientation films 22 and 23. It is formed. More specifically, the quarter-wave retardation layer 18 and the half-wave retardation layer 19 are formed by laminating a polymerizable liquid crystal monomer on the alignment films 22 and 23, and then raising the temperature to the phase transition point. It is produced by polymerizing a polymerizable liquid crystal monomer by irradiation to fix the alignment state of the liquid crystal. Although the ¼ wavelength retardation layer 18 and the ½ wavelength retardation layer 19 can widely apply various liquid crystal materials applicable to this type of optical film, in this embodiment, the same material is used. Applied. More specifically, for example, the compounds represented by the following chemical formulas (1) to (13) are used for the quarter-wave retardation layer 18 and the half-wave retardation layer 19.

  Although various adhesives such as an ultraviolet curable resin, a thermosetting resin, and a pressure sensitive adhesive can be widely applied to the adhesive layer 20, an ultraviolet curable resin is applied from the viewpoint of reducing the overall thickness. In this case, it can be formed with a thickness of about 1 μm. In this embodiment, an ultraviolet curable resin applied to the preparation of the alignment film is applied. An adhesive layer may be applied to the adhesive layer 20.

  The linearly polarizing plate 15 is provided with the optical functional layer 15B after the lower surface side of the base material 15A made of a transparent film such as TAC (triacetylcellulose) is saponified. In addition, 15 A of base materials replace with this, poly (meth) methyl acrylate, poly (meth) butyl acrylate, methyl (meth) acrylate- (meth) butyl acrylate copolymer, (meth) acrylate methyl- A resin such as an acrylic resin such as a styrene copolymer, a glass such as soda glass, potash glass, lead glass, or quartz glass can be used.

  The optical functional layer 15B is a part that bears an optical function as a linearly polarizing plate, and is produced, for example, by adsorbing and orienting iodine compound molecules on a film material made of polyvinyl alcohol (PVA).

  Thus, in the optical film 13, by configuring the quarter wavelength plate 16 with a laminate in which the quarter wavelength retardation layer 18 and the half wavelength retardation layer 19 are bonded by the adhesive layer 20, respectively. The ¼ wavelength phase difference layer 18 and the ½ wavelength phase difference layer 19 created by separate processes can be used, and thereby an alignment film and a phase difference layer are sequentially laminated. In this case, it can be created by effectively avoiding shortage of adhesion and insufficient adhesion, and as a result, it can be created with high stability and reliability.

  Further, the quarter-wave retardation layer alignment film 22 and the half-wave retardation layer alignment film 23 used for the production of the quarter-wave retardation layer 18 and the half-wave retardation layer 19 are respectively images. It is provided on the display panel 12 side and the linearly polarizing plate 15 side, whereby the transfer film is applied to produce the optical film 13 to reduce the overall thickness, and the quarter wavelength retardation layer alignment film 22, 1 / The alignment film 23 for the two-wavelength phase difference layer can function as a protective layer, and damage to the ¼ wavelength phase difference layer 18 and the ½ wavelength phase difference layer 19 can be reduced. The transfer method refers to, for example, when a desired layer is formed on a base material, the layer is not directly formed on the base material, but can be peeled once on a releasable support. After forming the transfer body by laminating the layers, the layer formed on the support is finally placed on the substrate (transfer base material) on which the layer is to be laminated according to the process, demand, etc. In this method, a desired layer is formed on the substrate by bonding and laminating, and then peeling and removing the support.

  In the optical film 13, various functional layers 10 such as an antireflection coating layer and a hard coating layer are provided on the side surface opposite to the optical functional layer 15 </ b> B of the base material 15 </ b> A provided on the linear polarizing plate 15 as necessary.

[Transcript]
In the optical film 13, the quarter-wave plate 16 and the linear polarizing plate 15 are integrated by the adhesive layer 17, and the transfer method is applied to a series of processes related to this integration. Thereby, in this embodiment, the substrate to be transferred is the linear polarizing plate 15, and the layers (transfer layers) used for transfer are the quarter-wave retardation layer alignment film 22 and the quarter-wave retardation layer 18. , An adhesive layer 20, a ½ wavelength phase difference layer 19, and a ½ wavelength phase difference layer alignment film 23.

  FIG. 3 is a diagram showing a configuration of a transfer film 21 which is this transfer body. The transfer film 21 is formed on the support base material 25, the quarter-wave retardation layer alignment film 22, the quarter-wave retardation layer 18, the adhesive layer 20, and the half-wave retardation layers 19, 1/2. A wavelength retardation layer alignment film 23 and a substrate 24 are provided.

  Here, the support base material 25 is a base material that is detachably supported after the transfer layer is detachably supported and the transfer layer is bonded and laminated on the transfer target substrate. In this embodiment, a PET (Polyethylene terephthalate) film, which is a transparent film material, is applied. The PET film is subjected to corona treatment as necessary, whereby the adhesion force is appropriately set. The support substrate 25 may be a resinous film material made of a resin such as a polyester resin such as polybutylene terephthalate or polyethylene aphthalate, or a polyolefin resin such as polypropylene or polymethylpentene.

  When the peelability from the transfer layer is insufficient, the support base material 25 is provided with a release layer that promotes peeling on the transfer layer side. Here, the release layer can be applied with a material having relatively high adhesion to the support substrate 25 (low peelability) and low adhesion to the transfer layer (high peelability). . In this embodiment, the lowermost layer of the transfer layer is an alignment film 22 for a quarter wavelength retardation layer made of an ultraviolet curable resin. Polymer compound), fluorine-based resin, melamine resin, epoxy resin, or a mixture of these resins and other resins (acrylic resin, cellulose-based resin, polyester resin, etc.) as appropriate.

  Incidentally, when the peelability by the release layer is insufficient, a release layer may be provided between the support substrate 25 and the release layer, and this release layer may be used to supplement the peelability by the release layer. . Note that a material having relatively low adhesion to the support film (high peelability) and high adhesion to the release layer (low peelability) can be applied to the release layer. More specifically, in this embodiment, the release layer includes an acrylic resin, a cellulose resin, a polyester resin, a urethane resin, a vinyl chloride-vinyl acetate copolymer, or a mixture of two or more selected from the above. Alternatively, a mixture of one or more selected from the above and other resins can be applied.

  The base material 24 is a base material that carries the transfer layer in a peelable manner and is used for peeling and removing as appropriate at the time of transfer or the like. In this embodiment, it is configured the same as the support base material 25. Moreover, also in the base material 24, in order to set appropriately the contact | adhesion power with the alignment film 23 for lower layer 1/2 wavelength phase difference layers, a corona process is performed as needed, and contact | adhesion power is improved.

〔Manufacturing process〕
FIG. 4 is a diagram for explaining the manufacturing process of the transfer film 21. In this manufacturing process, the half-wave retardation layer alignment film 23 and the half-wave retardation layer 19 are formed on the substrate 24 (FIG. 4A). In addition, the quarter-wave retardation layer alignment film 22 and the quarter-wave retardation layer 18 are formed on the substrate 25 (FIG. 4B). In the manufacturing process, the optical characteristics of the ½ wavelength phase difference layer 19 and the ¼ wavelength phase difference layer 18 are inspected by transmitted light, respectively, and then the ½ wavelength phase difference layer 19 and ¼ wavelength are obtained by the adhesive layer 20. The phase difference layer 18 is bonded together, thereby creating the transfer film 21 (FIG. 4C).

  In the case where the ½ wavelength phase difference layer 19 and the ¼ wavelength phase difference layer 18 are individually formed and integrated as in this embodiment, the ½ wavelength phase difference layer 19, 1 / The optical characteristics of the four-wavelength retardation layer 18 can be inspected. As a result, the quality can be improved and the optical film 13 can be produced stably.

  FIG. 5 is a diagram for explaining the manufacturing process of the optical film 13 that follows. In this manufacturing process, only the base material 24 is peeled from the transfer film 21 (FIG. 5A), and then attached to the linear polarizing plate 15 via the adhesive layer 17 (FIG. 5B), thereby supporting the manufacturing process. The optical film 13 is formed integrally with the body substrate 25 and the quarter-wave retardation layer alignment film 22 and with the half-wave retardation layer alignment film 23 left behind. In addition, although the process of peeling the base material 24 is provided in the manufacturing process of the transfer film 21 in this embodiment, it may be provided in the manufacturing process of the optical film 13.

  Thus, the alignment film 23 for a half-wave retardation layer protects the underlying half-wave retardation layer 19 until the substrate 24 is peeled off and bonded to the linearly polarizing plate 15.

  Subsequently, as shown in FIG. 6, in this step, after the support base material 25 is peeled from the optical film 13 (FIG. 6A), the adhesive layer 14 and the separator film are arranged to have a desired size. The optical film 13 is produced by cutting. In the subsequent manufacturing process of the image display device 11, in the final process, the separator film is peeled to expose the adhesive layer 14, and the optical film 13 is attached to the panel surface of the image display panel 12 through the adhesive layer 14 (FIG. 6). (B)). In addition, you may perform the process etc. which peel the support body base material 25 in the manufacturing process of an image display apparatus.

  As a result, the quarter-wave retardation layer alignment film 22 protects the upper quarter-wave retardation layer 18 after the substrate 25 is peeled off until it is bonded to the image display panel 12.

  FIG. 7 is a diagram showing the manufacturing process described above with reference to FIGS. 4 (A) and 4 (B). In FIG. 7, the structure in which the quarter-wave retardation layer alignment film 22 and the quarter-wave retardation layer 18 are formed on the base material 25 according to FIG. Show.

  In this manufacturing process, the base material 24 is pulled out from the supply reel 31, coated with a coating solution of an ultraviolet curable resin with a die 32, and then dried with a drying furnace 33. Note that the coating of the coating liquid is not limited to using a die, and various methods can be applied. In this manufacturing process, the roll plate 34 is a mold for molding in which the fine irregularities related to the alignment film 23 for the ½ wavelength retardation layer are formed on the peripheral side surface. In this manufacturing process, the base material 24 coated with an ultraviolet curable resin is pressed against a roll plate 34 by a pressure roller 35, and the ultraviolet curable resin is cured by irradiation with ultraviolet rays by an ultraviolet irradiation device 36 made of high-pressure mercury vapor. . Thus, in the manufacturing process, the uneven shape formed on the peripheral side surface of the roll plate 34 is transferred to the substrate 24. Thereafter, the substrate 24 is peeled off together with the ultraviolet curable resin cured from the roll plate 34 by the peeling roller 37, and a coating liquid of a liquid crystal material is applied by the die 39. Then, after drying in the drying furnace 40, the liquid crystal material is cured by irradiating ultraviolet rays from the ultraviolet irradiating device 41, and taken up on the take-up reel 42. By this series of treatments, the half-wave retardation layer alignment film 23 and the half-wave retardation layer 19 are formed on the substrate 24.

  Further, in this manufacturing process, instead of the roll plate 34, a roll plate 44 used for the production of the alignment film 22 for the quarter wavelength retardation layer is arranged, and similarly, the base material 25 is pulled out from the supply reel 31, After coating the coating solution of the ultraviolet curable resin by 32, the coating liquid is dried by the drying furnace 33, and the quarter wavelength retardation layer alignment film 22 is formed by the roll plate 44. Further, after the liquid crystal material is applied and dried, the liquid crystal material is cured and wound on the take-up reel 52, whereby the quarter-wave retardation layer alignment film 22 is formed on the substrate 25. The quarter wavelength retardation layer 18 is formed.

  FIG. 8 is a diagram for explaining the bonding process of the quarter wavelength retardation layer 18 and the half wavelength retardation layer 19 (FIG. 4C). In this manufacturing process, the laminate of the base material 24, the ½ wavelength retardation layer alignment film 23, and the ½ wavelength retardation layer 19 is drawn out from the take-up reel 42, and the ultraviolet curing as an adhesive is performed by the die 55. After the application of the conductive resin, the laminate of the substrate 25, the quarter-wave retardation layer alignment film 22 and the quarter-wave retardation layer 18 which are dried by the drying furnace 56 and pulled out from the take-up reel 52, Laminate. Thereafter, the ultraviolet curable resin applied by irradiating the ultraviolet rays with the ultraviolet irradiation device 57 is cured, and then the substrate 24 is peeled off and taken up on the take-up reel 58. Instead of integration with such an ultraviolet curable resin, it may be integrated with a dry laminate using a thermosetting resin, or may be further integrated with a PSA (Pressure Sensitive Adhesive) adhesive.

[Measures against scratches]
By the way, when the base material 24 is peeled and wound on a roll in this way, the outermost layer of the transfer layer is damaged due to the contact between the support base material 25 and the outermost layer of the transfer layer, and this scratch may deteriorate the yield of the optical film. There is. Therefore, in this embodiment, the hardness of the outermost layer of the transfer layer is set to be larger than the hardness of the support base material 25. If it does in this way, the damage in the case of laminating | stacking in roll shape can be made into the support body base material 25 side, and the damage of the outermost layer can be avoided effectively.

  Specifically, in this embodiment, since the outermost layer is the alignment film 23 for 1/2 phase difference layer, it is about 1/2 of the support base material 25 by setting the conditions relating to the production of the alignment film 23. The hardness of the alignment layer 23 for the retardation layer is increased. This condition includes an increase in the amount of ultraviolet irradiation, an increase in reactivity due to an increase in the amount of reaction initiator added to the coating solution, and the like.

  Further, this hardness is the pencil hardness, and against the pencil hardness F of the support substrate 25, the ½ retardation layer alignment film 23 is set to the pencil hardness H to prevent scratches. did it. In the evaluation of pencil hardness, a pencil scratch coating film hardness tester (electric type) (model: NP) manufactured by Toyo Seiki Seisakusho Co., Ltd. was used, and the load was 500 g and the speed was 0.5 mm / sec. Thus, the evaluation was repeated 5 times while changing the place at a distance of 10 mm or more.

[Second Embodiment]
FIG. 9 is a diagram showing an image display apparatus according to the second embodiment of the present invention in comparison with FIG. This image display device 61 is configured in the same manner as in the first embodiment except that an optical film 63 is applied instead of the optical film 13. The optical film 63 is configured in the same manner as the optical film 13 except that the transfer layer 66 includes the ½ wavelength retardation layer 19, the adhesive layer 20, and the ¼ wavelength retardation layer 18.

  FIG. 10 is a cross-sectional view showing a transfer film according to the optical film 61. The optical film 63 is produced by applying the transfer film 71. In the transfer film 71, the transfer layer 66 is formed of the half-wave retardation layer 19, the adhesive layers 20, 1, by setting the adhesion between the layers. When the substrate 24 and the support substrate 25 are peeled off by the ¼ wavelength phase difference layer 18, the ½ wavelength phase difference layer alignment film 23 and the ¼ wavelength phase difference layer alignment respectively. The membrane 2 is peeled together.

  In this embodiment, the transfer layer 66 is thus constituted by the ½ wavelength retardation layer 19, the adhesive layer 20, and the ¼ wavelength retardation layer 18, and the ½ wavelength retardation layer which is the outermost layer. The hardness of 19 is set to be larger than the hardness of the support base material 25, thereby effectively avoiding scratching of the half-wave retardation layer 19.

[Other Embodiments]
The specific configuration suitable for the implementation of the present invention has been described in detail above. However, the present invention can be variously combined or modified with the configuration of the above-described embodiment without departing from the spirit of the present invention. Can do.

  That is, in the above-described embodiment, the case where the alignment film is formed by the shaping process has been described. However, the present invention is not limited to this, and can be widely applied to the case where the alignment film is formed by so-called photo-alignment.

2, 15A, 24, 25 Base material 3, 23 Alignment film for 1/2 wavelength retardation layer (alignment film)
4, 19 1/2 wavelength retardation layer 5, 22 Alignment film for 1/4 wavelength retardation layer (alignment film)
6, 18 1/4 wavelength retardation layer 7, 16 1/4 wavelength plate 11, 61 Image display device 12 Image display panel 13, 63 Optical film 14 Adhesive layer 15 Linearly polarizing plate 15B Optical functional layer 16, 66 1/4 Wave plate (transfer layer)
17, 20 Adhesive layer 21, 61 Transfer film 31 Supply reel 32, 39 Die 33, 40 Drying furnace 34, 44 Roll plate 35, 37 Roller 36, 41, 57 Ultraviolet irradiation device 42, 52, 58 Take-up reel 55 Die 56 drying furnace

Claims (5)

A transfer body for an optical film comprising a support substrate and a transfer layer,
The transfer layer is
A quarter-wave retardation layer that imparts a phase difference of ¼ wavelength to transmitted light, a ½ wavelength retardation layer that imparts a phase difference of ½ wavelength to transmitted light, and the ¼ An adhesive layer for adhering the wavelength retardation layer and the ½ wavelength retardation layer,
From the support substrate side, the 1/4 wavelength retardation layer, the adhesive layer, and the 1/2 wavelength retardation layer are laminated in this order.
For optical films in which the hardness of the half-wave retardation layer, which is the outermost layer on the side opposite to the support substrate side of the transfer layer, is one or more steps in the evaluation of pencil hardness with respect to the support substrate. Transcript. The transfer body for optical films according to claim 1, wherein the transfer body is a roll body with the support base material inside. The optical film which bonded together the said transfer layer of the transfer body for optical films of Claim 1 or Claim 2 with the linearly-polarizing plate. A method for producing a transfer body for an optical film comprising a support substrate and a transfer layer,
1/4 wavelength retardation layer is prepared on the support substrate, and a laminate of the support substrate and 1/4 wavelength retardation layer alignment film is prepared. A step of preparing an alignment film for the retardation layer;
A quarter-wave retardation layer is prepared in a laminate of the support substrate and the quarter-wave retardation layer alignment film, and the support substrate, the quarter-wave retardation layer alignment film, A quarter-wave retardation layer producing step of producing a laminate of quarter-wave retardation layers;
An alignment film for a ½ wavelength retardation layer is prepared on a substrate for a ½ wavelength retardation layer, and the substrate for the ½ wavelength retardation layer, the ½ wavelength retardation layer is formed. An alignment film preparation step for a half-wave retardation layer for preparing a laminate of alignment films for use;
A half-wave retardation layer was prepared on the laminate of the base material for the half-wave retardation layer and the alignment film for the half-wave retardation layer. A half-wave retardation layer producing step of producing a laminate of a substrate, a half-wave retardation layer alignment film, and a half-wave retardation layer;
Laminating the ¼ wavelength retardation layer and the ½ wavelength retardation layer, a laminate of the support substrate, the ¼ wavelength retardation layer alignment layer, and a ¼ wavelength retardation layer; A bonding step of integrating the base material for the half-wavelength retardation layer, the alignment film for the half-wavelength retardation layer, and the laminate of the half-wavelength retardation layer;
A peeling step of peeling the laminate of the half-wave retardation layer and the alignment layer for the half-wave retardation layer from the laminate integrated by the bonding step,
In the half wavelength retardation layer manufacturing step,
With respect to the support substrate, the hardness of the half-wave retardation layer, which is the outermost layer on the side opposite to the support substrate side of the transfer layer, is increased by one or more steps in the pencil hardness evaluation. A method for producing an optical film transfer body, wherein the half-wave retardation layer is prepared. The manufacturing method of the optical film which bonds together the said transfer layer on the linearly-polarizing plate from the transfer body for optical films of Claim 4, and integrates them.

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