JP2017049392A - Transfer body for optical film, optical film, and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remarkably reduce the occurrence of defects due to repelling compared with a prior art in a configuration where an alignment film and phase difference layer are sequentially manufactured on a base material.SOLUTION: There is provided a transfer body 15 for an optical film comprising at least a base material 17, an alignment film 8 formed on the base material 17, and a phase difference layer 6 providing a phase difference to transmitted light, where at least the phase difference layer 6 is transferred to a transfer target body with the use of a transfer method, wherein a surface of the base material 17 on the alignment film 8 side is a smooth surface having an arithmetic average roughness Ra of 5 nm or more and less than 20 nm, and a surface on the opposite side of the alignment film 8 is an anti-blocking surface.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an optical film transfer body, an optical film using the optical film transfer body, and an image display device.

  Conventionally, a method has been proposed in which an antireflection film is formed by laminating a linearly polarizing plate and a quarter-wave plate on the exit surface of an image display panel, and the reflection of extraneous light is reduced by this antireflection film. This antireflection film converts extraneous light directed to the panel surface of the image display panel into linearly polarized light by a linear polarizing plate and then converts it into circularly polarized light by a quarter wavelength plate. 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 this reflection. As a result, the reflected light is converted from linearly polarized light in the direction shielded by the linear polarizing plate from the quarter wavelength plate, contrary to the arrival time, and then shielded by the subsequent linear polarizing plate. Outgoing emission is significantly suppressed.

  With respect to this antireflection film, Patent Document 1 and the like disclose that this light is transmitted through a linearly polarizing plate by laminating a half-wave plate and a quarter-wave plate to form a quarter-wave plate. A configuration is disclosed in which a quarter-wave plate formed by stacking a half-wave plate and a quarter-wave plate functions with reverse dispersion wavelength characteristics.

  Such a half-wave plate and a quarter-wave plate are produced, for example, by sequentially forming an alignment film and a retardation layer on a substrate made of a transparent film. In addition, the retardation layer coats the liquid crystal material in a state of being aligned by the alignment regulating force of the alignment film by applying the coating liquid relating to the retardation layer on the alignment film, drying and then curing. Produced.

  In addition, for example, Patent Document 2 proposes a method of manufacturing an optical film disposed on the exit surface of such an image display panel by a so-called transfer method. Here, the transfer method means that, for example, when a desired layer is formed on a substrate, this layer is not directly formed on the substrate, but once on a support which is a releasable substrate. After the layer is formed in a peelable manner to produce a transfer body, the layer formed on the support is finally formed according to the process, demand, etc. In this method, a desired layer is formed on the base material by bonding and laminating on the base material and then peeling off and removing the support.

  By the way, when forming a half-wave plate, a quarter-wave plate, etc. by sequentially forming an alignment film and a retardation layer on the surface of the substrate, the coating liquid related to the retardation layer is repelled on the alignment film surface, As a result, defects may occur in the retardation layer. If such a defect is large, it is recognized by a white spot or the like when placed on the image display panel, and the quality of the display screen is remarkably lowered. Even when the size is small and the white film or the like cannot be recognized, the characteristics of the optical film are deteriorated. Specifically, in the antireflection film, the reflectance increases due to the presence of such defects, and the antireflection performance deteriorates. As a result, it is desirable to minimize the occurrence of defects due to repelling.

JP-A-10-68816 Japanese Patent No. 4598950

  The present invention has been made in view of such a situation, and in the configuration in which an alignment film and a retardation layer are sequentially produced on a substrate, the occurrence of defects due to repelling is significantly reduced as compared with the prior art. For the purpose.

  The present inventor has conducted extensive research to solve the above-mentioned problems, and for a substrate for producing an alignment film under the retardation layer, the side on which the orientation film is produced is a smooth surface, and the side on which the orientation film is produced. It came to the idea that the opposite side surface is an anti-blocking surface, and the present invention was completed.

(1) At least a support, an alignment film formed on the support, and a retardation layer that imparts a retardation to transmitted light, and at least the retardation layer is transferred to a transfer object by a transfer method A transfer body for optical film,
The support is
The alignment film side surface is a smooth surface having an arithmetic average roughness Ra of 5 nm or more and less than 20 nm,
A side surface opposite to the alignment film is an anti-blocking surface.

  According to (1), when the side opposite to the alignment film is an anti-blocking surface, blocking can be prevented and productivity can be improved. In addition, since the side surface of the alignment film is a smooth surface having an arithmetic average roughness Ra of 5 nm or more and less than 20 nm, it is possible to prevent the occurrence of a convex portion as a starting point of repelling. The occurrence of defects due to repelling can be reduced.

(2) In (1),
The smooth surface on the side of the alignment film is
The transfer body for optical films which is a smooth surface by the resin material in which the filler is not mixed.

  According to (2), the occurrence of defects due to repelling can be significantly reduced with a more specific configuration than in the past.

(3) In (1) or (2),
The support is any one of a PET film, a TAC film, and a COP film.

  According to (3), the occurrence of defects due to repelling can be significantly reduced as compared with the conventional case by blocking and improving productivity with a more specific configuration.

  (4) An optical film produced by transferring the retardation layer of the transfer member for an optical film according to any one of (1), (2), and (3) by a transfer method.

  According to (4), using a transfer body for an optical film, which prevents blocking and improves the productivity, and significantly reduces the occurrence of defects due to repelling compared to the conventional case. An optical film can be produced.

  (5) An image display device in which the optical film according to (4) is disposed on the panel surface of the image display panel.

  According to (4), it is possible to provide an image display device using an optical film formed by reducing defects as compared with the prior art.

  According to the present invention, in the configuration in which an alignment film and a retardation layer are sequentially formed on a substrate, it is possible to significantly reduce the occurrence of defects due to repelling as compared with the conventional case.

It is a figure 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 which concerns on the image display apparatus of FIG. It is a figure which shows the transfer body for optical films which concerns on the optical film of FIG. It is a figure where it uses for description of repellency.

[First Embodiment]
FIG. 1 is a diagram showing an image display apparatus according to the first embodiment of the present invention. In this image display device 1, an optical film 4 made of an antireflection film is disposed on the panel surface (viewer side surface) of the image display panel 2 with an adhesive layer 3 interposed therebetween. Here, in this embodiment, the image display panel 2 may be a liquid crystal display panel or the like although an organic EL image display panel which is an image display panel using self-luminous elements is applied.

  The optical film 4 is an antireflection film formed by laminating a quarter-wave plate and a linearly polarizing plate 5, and this quarter-wave plate gives a half-wave phase difference to transmitted light by a half-wave. The phase difference layer 6 and the quarter wavelength phase difference layer 7 that imparts a quarter wavelength phase difference to the transmitted light are produced. In addition, as shown in FIG. 2, the slow axes (indicated by arrows respectively) of the ½ wavelength phase difference layer 6 and the ¼ wavelength phase difference layer 7 with respect to the transmission axis of the linearly polarizing plate 5 indicated by arrows. Are arranged so as to form angles of 15 degrees and 75 degrees counterclockwise, respectively. Thereby, the quarter wavelength plate is configured to function with a wavelength characteristic of reverse dispersion with respect to the transmitted light of the linearly polarizing plate 5.

  In the optical film 4, the half-wave retardation layer 6 and the quarter-wave retardation layer 7 are sequentially integrated with the corresponding alignment films 8 and 9 through the adhesive layers 10 and 11 by a transfer method. And is laminated on the linear polarizing plate 5. More specifically, the optical film 4 is formed by laminating a laminated body of the ½ wavelength retardation layer 6 and the alignment film 8 on the linear polarizing plate 5 by a transfer method, and then, further, a ¼ wavelength retardation layer 7 and an alignment film 9. The laminate is prepared by laminating the laminate of the half-wave retardation layer 6, the alignment film 8, and the linear polarizing plate 5 by a transfer method. Thus, the optical film 4 is comprised so that the whole thickness can be made thin by laminating | stacking by the transfer method. Instead of laminating the half-wave retardation layer 6 and the quarter-wave retardation layer 7 together with the corresponding alignment films 8 and 9 on the linear polarizing plate 5 in this way, the half-wave retardation layer 6 is used. Only the quarter-wave retardation layer 7 may be transferred.

  In the linear polarizing plate 5, an optical functional layer having an optical function as a linear polarizing plate is produced by adsorbing and orienting iodine compound molecules on a film material made of, for example, polyvinyl alcohol (PVA). It is configured to be held by a base material made of a transparent film such as Triacetylcellulose. For example, an ultraviolet curable resin is applied to the adhesive layers 10 and 11.

  FIG. 3 is a sectional view showing an optical film transfer body 15 used for transferring the half-wave retardation layer 6 and the alignment film 8. In addition, the transfer body 16 for optical films used for the transfer of the 1/4 wavelength phase difference layer 7 and the alignment film 9 is different except that the alignment direction of the alignment film 8, the film thickness and the alignment direction of the phase difference layer 7 are different. By being configured in the same manner as the optical film transfer body 15, the optical film transfer body 16 is indicated by corresponding reference numerals in parentheses in FIG. 3, and redundant description is omitted.

  Here, in the transfer body 15 for an optical film, an alignment film 8 and a retardation layer 6 are sequentially formed on a support 17 that is a base material. The optical film transfer body 15 is formed by attaching the retardation layer 6 to the linearly polarizing plate 5 by the adhesive layer 10 and holding it on the linearly polarizing plate 5, and then peeling the support 17. A film 8 and a retardation layer 6 are laminated on the linear polarizing plate 5. In this manner, in the optical film transfer body 16, the retardation layer 7 and the alignment film 9 are then laminated on the laminate of the retardation layer 6, the alignment film 8, and the linear polarizing plate 5 in the same manner.

  Here, various transparent film materials can be applied to the support body 17, but in this embodiment, a PET (Polyethylene terephthalate) film is applied. The optical film transfer body 15 is cured in a state where the liquid crystal material related to the retardation layer 6 is aligned by the alignment regulating force of the alignment film 8 formed on the support 17, thereby preparing the retardation layer 6. Thus, a desired phase difference is given to the transmitted light.

  Various liquid crystal materials applied to this type of optical film can be widely applied to the retardation layer 6. More specifically, the retardation layer 6 contains a polymerizable liquid crystal composition. This polymerizable liquid crystal composition can contain an antiblocking agent and the like in addition to a liquid crystal compound exhibiting liquid crystallinity and having a polymerizable functional group in the molecule (hereinafter also referred to as “rod-like compound”). In place of the rod-shaped compound, a liquid crystal compound using a discotic liquid crystal may be applied.

  The rod-shaped compound has a refractive index anisotropy, and has a function of imparting a desired phase difference by regularly arranging with the alignment regulating force of the alignment film 8. Examples of the rod-like compound include materials exhibiting a liquid crystal phase such as a nematic phase and a smectic phase, but the nematic phase is easier to arrange regularly than liquid crystal compounds exhibiting other liquid crystal phases. It is more preferable to use the rod-shaped compound shown.

  Specific examples of the rod-shaped compound used in the present embodiment include compounds represented by the following formulas (1) to (16).

  In addition, for example, a configuration disclosed in Japanese Patent Application Laid-Open No. 2012-042530, Japanese Patent Application Laid-Open No. 2005-283670, and the like can be widely applied to a liquid crystal compound using a discotic liquid crystal.

More specifically, for example, the following liquid crystal compounds disclosed in JP 2001-183643 A and JP 9-073081 A can be applied.

  In this embodiment, a photo-alignment film is applied to the alignment film 8. For this photo-alignment film, various photo-alignment film materials capable of setting the alignment regulating force by irradiation with polarized ultraviolet rays can be applied. More specifically, in this embodiment, for example, a light dimerization type material is applied to the alignment film 8. The light dimerization type material is described in “M. Schadt, K. Schmitt, V. Kozinkov and V. Chigrinov: Jpn. J. Appl. Phys., 31, 2155 (1992)”, “M. Schadt, 1992”. H. Seiberle and A. Schuster: Nature, 381, 212 (1996) "can be used. The alignment film 8 is produced with a film thickness of 50 nm or more and 200 nm or less, and in this embodiment, it is produced with a film thickness of 100 nm.

  Instead of the alignment film 8 made of a photo-alignment film, an alignment film made by a rubbing process such as a polyimide film or PVA, an alignment film made by a rubbing process for the substrate itself, or the like may be applied.

[Detailed structure of support]
Furthermore, in this embodiment, the support 17 has a smooth surface on the side on which the alignment film 8 is produced, and an anti-blocking surface on the side opposite to the side on which the alignment film 8 is produced. Here, the smooth surface is formed with an arithmetic average roughness Ra of 5 nm or more and less than 20 nm, preferably 10 nm or more and less than 20 nm. The arithmetic average roughness Ra is in accordance with JIS B0601. In this embodiment, the smooth surface is made of a resin material in which no filler is mixed. Thereby, in this embodiment, while blocking is ensured and sufficient productivity is ensured, generation | occurrence | production of the defect by repelling is reduced compared with the past.

  That is, conventionally, the base material used for the production of such an optical film is provided by being wound in a roll shape, and in the production process of the optical film, the base material is pulled out from the roll and sequentially processed. To produce optical films. Moreover, in this production process, the intermediate product is appropriately wound up in a roll shape and conveyed to the next process for convenience of the process. The PET film applied to the support as the base material will be laminated when it is wound up in a roll shape, and if no anti-blocking treatment is applied, the PET film wound up in a roll shape will be Then, it comes to stick to the overlapping PET film or other members (so-called blocking), and the productivity is remarkably lowered.

  For this reason, anti-blocking property is conventionally aimed at by PET film mixing with a filler. Here, as the filler, for example, translucent fine particles made of a resin material, fine particles made of an inorganic material typified by silica or the like can be applied, and fine particles having a particle diameter of 4 to 7 μm are applied. When fine particles are mixed in this way, an anti-blocking surface is formed on the surface of the PET film by the fine concavo-convex shape surface corresponding to the fine particles, and the PET film is held so as not to adhere to the fine concavo-convex shape. As a result, anti-blocking properties are achieved.

  However, as a result of detailed studies, it has been found that such fine irregularities in the optical film transfer body 15 are the cause of defects due to repelling. That is, as shown in FIG. 4, the convex part 20 will generate | occur | produce on the surface of the support body 17 by mixing of a filler. When the height h of this convex part 20 is larger than the film thickness of the alignment film 8, the coating liquid is repelled in the range of the circular shape centering on this convex part 20 in the retardation layer 6, and as a result The circular area centered on the convex portion 20 becomes a defect due to repelling.

  Such a defect due to repelling is caused by a circular region having a diameter D corresponding to the size of the convex portion 20 with the convex portion 20 as the center. Accordingly, in this embodiment, the side on which the alignment film 8 is manufactured is a smooth surface made of a resin material in which no filler is mixed, and the occurrence of convex portions that cause such defects is prevented. Thereby, in this embodiment, the repelling is prevented and the occurrence of defects due to the repelling is effectively avoided.

  Here, in the convex portion 20, when it is sufficiently smaller than the thickness of the alignment film 8, it is covered with the resin material of the alignment film 8, and in this case, the phase difference layer 6 is prevented from being repelled. Generation of defects is prevented. Thus, the height of the convex portion 20 is made at least smaller than the thickness of the alignment film 8, more preferably, the height of the convex portion 20 is made smaller than ½ of the thickness of the alignment film 8. The occurrence of defects can be specifically and reliably prevented. In addition, in such a convex part 20, the measurement method of the maximum height Ry prescribed | regulated to JISB0601'1994 is applied, and an atomic force microscope (AFM) or a scanning electron microscope (Scanning) is applied. It can be obtained by processing the data of the surface shape of the support 17 obtained by using Electron Microscope (SEM) or the like. Here, in the alignment film 8 of the photo-alignment film, the convex part 20 is more preferably 25 nm or less so as to have a height h of 50 nm or less by being manufactured with a film thickness of 50 nm or more and 200 nm or less. It is desired that the height h is set to be h.

  More specifically, in this embodiment, the support 17 is produced by two-layer extrusion using a base material in which no filler is mixed and a filler mixed material in which a filler is mixed in the base material. It is produced by a laminate of a resin layer made of only a material and a resin layer made of a filler mixed material. The support 17 is formed of a resin layer made of only the base material to form a smooth surface made of a resin material in which no filler is mixed. Further, an anti-blocking surface is formed by the resin layer made of the filler mixed material. In addition, the support body may use a single material mixed with a filler, for example, by applying a melt casting method or the like to control the distribution of the filler to make the side surface of the alignment film a smooth surface.

  Here, from the viewpoint of preventing such defects due to repelling, it is desirable that the smooth surface has as small an arithmetic average roughness Ra as possible. However, it is necessary to appropriately manage the peel strength from the support 17 by producing the optical film 4 by peeling the retardation layer 6 from the support 17 integrally with the alignment film 8 by a transfer method.

  From the viewpoint of setting such peel strength to an appropriate value, and further from the viewpoint of sufficiently ensuring the anti-blocking property of the support, the smooth surface of the substrate is, as described above, the lower limit of the arithmetic average roughness Ra. The value is 5 nm or more, more preferably 10 nm or more. Thereby, the transfer films 15 and 16 have a peel strength of the retardation layer 6 and the alignment film 8 with respect to the support 17 (a peel strength according to a 180 degree peel test specified in JIS K6854-2) of 0.03 N or more / 25 mm width. 0.4 N or less / 25 mm width, more preferably 0.04 N or more / 25 mm width 0.2 N or less / 25 mm width.

[Measurement results]
Here, a comparison result was obtained between Comparative Example 1 and Example 1. In Comparative Example 1, a transfer film for an optical film was prepared using a PET film prepared only from a filler-mixed material mixed with a filler as a support, and the structure described above with reference to FIG. It is an antireflection film. Example 1 is a PET film produced by two-layer extrusion using a base material in which no filler is mixed, and a filler mixed material in which a filler is mixed in the base material, according to the above-described embodiment. It is the antireflection film produced on the same conditions as the comparative example 1 except the point which is a film.

  About this comparative example 1 and Example 1, the defect was observed and the reflectance was measured further. A spectrocolorimeter (Konica Minolta CM-2600d) was used for the reflectance measurement. In Comparative Example 1, about 2 to 3 defects having a diameter D of about 100 μm were detected in a rectangular region having a side of 1.5 cm. Here, at the location of this defect, the desired phase difference cannot be imparted to the transmitted light, so that sufficient antireflection cannot be achieved. As a result, in Comparative Example 1, an increase in reflectance is predicted. According to the result of actual measurement, the reflectance of Comparative Example 1 was 5.5 in terms of Y value. On the other hand, in Example 1, such a defect could not be found, and the antireflection rate was 5.2 in terms of Y value. Further, the peel strengths of the retardation layer 6 and the alignment film 8 with respect to the support 17 were values that could be sufficiently used for mass production.

  According to the above configuration, blocking is effectively avoided by making the alignment film side of the support a smooth surface made of a resin material in which no filler is mixed, and making the side surface opposite to the alignment film side an anti-blocking surface. Defects due to repelling can be effectively avoided. By using an optical film transfer body produced using such a support, an optical film in which defects due to repelling are significantly reduced as compared to conventional ones, and an image display device using this optical film are provided. Can be provided. Moreover, a transfer body with good orientation can be obtained by making the side surface of the alignment film smooth as described above.

  In addition, by configuring this support with a PET film, by further producing a support by two-layer extrusion of a resin material mixed with a filler and a resin material not mixed with a filler, by a more specific configuration, Blocking can be sufficiently prevented, and the occurrence of defects due to repelling can be significantly reduced as compared with the conventional case.

[Second Embodiment]
In this embodiment, so-called optical compensation (phase difference compensation), an optical film used for improving viewing angle characteristics, an optical film transfer body using a positive C plate used for the optical film, and an image display using the optical film The present invention is applied to an apparatus. Thereby, in this embodiment, in place of the retardation layer and the alignment film according to the A plate, the retardation layer and the alignment film according to the positive C plate are produced to constitute the optical film transfer body. The positive C plate is transferred to a linear polarizing plate or the like related to optical compensation and viewing angle characteristics to produce an optical film, and this optical film is arranged to constitute an image display device.

  In this embodiment, the same support as described above for the first embodiment is applied to the optical film transfer body. As a result, in this embodiment, even when a positive C plate is formed by the retardation layer, as in the first embodiment, it is possible to effectively avoid the deterioration of productivity and to prevent defects due to repelling compared to the conventional case. The occurrence of this is greatly reduced.

  According to this embodiment, even when the positive C plate is configured by the retardation layer, the same effect as that of the above-described embodiment can be obtained.

[Third Embodiment]
In this embodiment, instead of a PET film material, a TAC (Triacetylcellulose) film material or a COP (Cyclo Olefin Polymer) film material is applied to the support. This embodiment is configured in the same manner as the first embodiment or the second embodiment except that the configuration relating to the support is different.

  Here, for example, as the TAC film material, for example, a two-layer film material disclosed in JP-A-2007-254699 and a three-layer film material disclosed in JP-A-2009-276679 can be applied. Further, as the COP film material, the film material disclosed in JP 2011-128356 A can be applied. Further, the TAC film material and the COP film material may be produced by unevenly distributing fillers by a melt casting method or the like.

[Measurement results]
[Example 2]
A mixed composition for layer A in which 99 wt% of cycloolefin polymer and 1 wt% of spherical silica particles are mixed, a composition for layer B by 100 wt% of cycloolefin polymer, 99.9 wt% of cycloolefin polymer and 0.1 wt% of spherical silica particles % Is mixed by melt coextrusion with a single-screw extruder and wound into a roll. A layer having a thickness of 10 μm, a B layer having a thickness of 100 μm, and a thickness of 10 μm A 400 m long support consisting of three layers with the C layer was prepared. This support had good antiblocking properties. Further, the arithmetic average roughness Ra of the surface of the C layer was 5 nm. The cycloolefin polymer is ZEONOR 1020R (manufactured by Nippon Zeon), the spherical silica particles in the A layer are Admafine S0-E2 (manufactured by Admatex), and the spherical silica particles in the C layer are Admafine S0-E1. It was used. The anti-blocking property is 10 N / cm by using a permanent strain tester (manufactured by Tester Sangyo Co., Ltd.) by laminating the support in the same direction as the front and back when cutting 6 pieces of the support into 3 cm square and winding up in a roll shape. The peeling state after applying a weight of ² at room temperature and normal pressure for 48 hours was observed, and the case where it was not attached was judged to be good.

On the side of the C layer of the support thus produced, the alignment film coating liquid is applied with a thickness of 200 nm, dried, and then irradiated with ultraviolet rays for polymerization, followed by rubbing treatment. Thus, an alignment film was produced. The coating liquid was prepared by diluting the following mixture with a mixed solvent of MEK: MIBK = 10: 1 so that the solid content was 20%. MEK is an abbreviation for methyl ethyl ketone, and MIBK is an abbreviation for methyl isobutyl ketone.
Urethane (meth) acrylate oligomer (Nippon Synthetic Chemical Co., Ltd. UV1700B (solid content 100%)): 50 parts by weight PETA (Kyoeisha Chemical Co., Ltd. light acrylate PE-3A (solid content 100%): 50 parts by weight Photopolymerization initiator ( BASF Lucillin TPO): 4 parts by weight

On the alignment film thus prepared, the retardation layer coating solution is applied to a dry thickness of 1.1 μm, and after drying, it is polymerized by irradiating with ultraviolet rays. Obtained. In addition, the following mixtures were applied to this phase difference layer coating liquid.
Polysynthetic liquid crystal composition (RMS03-013 manufactured by Merck & Co., Inc.): 100 parts by weight Fluorine leveling agent (LE-604 manufactured by Kyoeisha Chemical Co., Ltd.): 0.25 parts by weight

  It was 130 nm when the phase difference of the obtained transcription | transfer body for optical films was measured with the phase difference measuring apparatus (KOBRA-WR, Oji Scientific Instruments company make). Adhere the linear polarizing plate with adhesive and the retardation layer of the resulting optical film transfer body so that the absorption axis of the linear polarizing plate and the slow axis of the retardation layer form an angle of 45 °. In addition, the support was peeled off to obtain a circularly polarizing plate. The obtained circularly polarizing plate was free from defects and retardation unevenness and had good performance as a circularly polarizing plate. Further, the peel strengths of the retardation layer 6 and the alignment film 8 with respect to the support 17 were values that could be sufficiently used for mass production.

Example 3
The cellulose solution A, the cellulose solution B, and the cellulose solution C are sequentially cast and wound up into a roll, and the A layer having a thickness of 6 μm made of the cellulose solution A and the B layer having a thickness of 60 μm made of the cellulose solution B. And the support body by which the 6-micrometer-thick C layer which consists of a cellulose solution C was laminated | stacked was obtained. The obtained support had good antiblocking properties. The cellulose solution A, cellulose solution B, and cellulose solution C are as follows.

Cellulose solution A
Triacetyl cellulose: 17 parts by weight Triphenyl phosphate: 3 parts by weight Methylene chloride: 90 parts by weight Methanol: 10 parts by weight Silica fine particles (average particle size: 16 nm) (Aerosil R972 manufactured by Nippon Aerosil): 0.5 parts by weight

Cellulose solution B
Triacetyl cellulose: 17 parts by weight Triphenyl phosphate: 15 parts by weight Methylene chloride: 90 parts by weight Methanol: 10 parts by weight

Cellulose solution C
Triacetyl cellulose: 17 parts by weight Triphenyl phosphate: 3 parts by weight Methylene chloride: 90 parts by weight Methanol: 10 parts by weight Silica fine particles (average particle size 16 nm) (Aerosil R972 manufactured by Nippon Aerosil): 5 parts by weight

  Here, the arithmetic average roughness Ra of the surface of the layer A was 35 nm. An orientation film and a retardation layer were laminated on the A layer side of the obtained support in the same manner as in Example 2 to obtain a first transfer member for an optical film. However, the mixed solvent of the alignment film coating solution was a mixed solution of toluene: MEK = 10: 1. The phase difference of the first optical film transfer body was measured in the same manner as in Example 2. As a result, it was 130 nm.

  In addition, an alignment film and a retardation layer were laminated on the A layer side of another support obtained in the same manner as in Example 2 to obtain a second optical film transfer body. However, the mixed solvent of the alignment film coating solution was a mixed solution of toluene: MEK = 10: 1. Further, in this second optical film transfer body, the coating film thickness relating to the retardation layer was set to a dry film thickness of 2 μm. The retardation of the second optical film transfer member was measured in the same manner as in Example 2. As a result, it was 245 nm.

  After laminating the linear polarizing plate with an adhesive and the retardation layer of the second optical film transfer body so that the absorption axis of the linear polarizing plate and the slow axis of the retardation layer form an angle of 15 ° The support was peeled off. Still further, the alignment layer of the second optical film transfer member and the retardation layer of the first optical film transfer member are connected to the absorption axis of the linear polarizing plate and the retardation layer of the retardation layer through the adhesive layer. A circularly polarizing plate was obtained by laminating the axes so as to form an angle of 74 °. The obtained circularly polarizing plate was free from defects and retardation, and had good performance as a broadband circularly polarizing plate. Further, the peel strength of the retardation layer 6 and the alignment film 8 with respect to the support 17 was also a value that could be sufficiently used for mass production.

[Comparative Example 2]
Comparative example 2 was produced and examined in comparison with Example 3. Here, Comparative Example 2 was produced in the same manner as Example 3 except that the coated layer was the C layer side of the support of Example 3. Here, the arithmetic average roughness Ra of the surface of the C layer was 210 nm. In Comparative Example 2, as in Comparative Example 1, defects occurred and a large number of retardations were observed.

[Comparative Example 3]
In Example 2, the support was made in the same manner as in Example 2 except that the cycloolefin polymer of the C layer was 99.7 wt%, the spherical silica particles were 0.2 wt%, and the A layer was not used. And an optical film was produced from this support. Here, the arithmetic average roughness Ra of the surface of the B layer was 3 nm. Further, in the evaluation of the antiblocking property of this support, some sticking was observed. The support is once wound on a roll, and then unwound and the alignment layer 6 and the retardation layer 2 are laminated on the surface of the B layer in the same manner as in Example 2. As a result, the retardation layer 6 and the alignment film 8 with respect to the support 17 are stacked. The peel strength was higher than that of Example 2, and it was found that there was a problem in mass productivity in consideration of manufacturing variation.

Example 4
Except that the content of silica fine particles in the cellulose solution A was 0.3 parts by weight, a film was formed in the same manner as in Example 3 to prepare a support having a three-layer structure. The produced support had good antiblocking properties. Here, the arithmetic average roughness Ra of the surface of the A layer was 19 nm.

After the alignment film was produced in the same manner as in Example 3, the following retardation layer coating solutions were used to obtain first and second optical film transfer bodies. The phase differences of the first and second optical film transfer bodies were 135 nm and 250 nm, respectively.

Retardation layer coating liquid (2-1) Discotic liquid crystal in which R is all (2-2): 10 parts by weight Photopolymerization initiator (Irgacure 907 manufactured by Chiba): 0.4 part by weight MEK: 67 weights Part

  A retardation layer was bonded to a linear polarizing plate with an adhesive in the same manner as in Example 3 using the first and second optical film transfer bodies to obtain a circularly polarizing plate. The obtained circularly polarizing plate was free from defects and retardation, and had good performance as a broadband circularly polarizing plate.

  Thus, even if it applies a TAC film material and a COP film material to a support body, the effect similar to 1st Embodiment and 2nd Embodiment can be acquired.

  Further, since the TAC film material and the COP film material have low birefringence, the optical properties are inspected at the stage of the transfer body by applying the TAC film material and the COP film material to the support as in this embodiment. Can be used for product management.

Example 5
In Example 5, a circularly polarizing plate was produced in the same manner as in Example 3 except that the amount of filler in the cellulose solution A of layer A in Example 3 was 0.7 parts by weight. The arithmetic average roughness Ra was 48 nm. In Example 6, although slight defects were observed, the broadband circularly polarizing plate had relatively good performance.

Example 6
In Example 6, the configuration according to Example 1 was applied as the coating liquid for alignment film in Example 2 to form a photo-alignment film with a thickness of 100 nm, and then irradiated with polarized ultraviolet rays. A circularly polarizing plate was produced in the same manner. The obtained circularly polarizing plate was free from defects and retardation, and had good performance as a broadband circularly polarizing plate.

Example 7
A support was prepared in the same manner as in Example 7 except that the mixed composition for the C layer in Example 2 was a composition in which 99.8 wt% of the cycloolefin polymer and 0.22 wt% of the spherical silica particles were mixed. . The obtained support had good antiblocking properties. The arithmetic average roughness Ra on the surface of the C layer was 10 nm. The obtained circularly polarizing plate was free from defects and retardation, and had good performance as a broadband circularly polarizing plate. Further, the peel strength of the retardation layer 6 and the alignment film 8 with respect to the support 17 was also a value that could be sufficiently used for mass production.

[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 anti-blocking surface is produced by mixing the filler is described. However, the present invention is not limited to this, and the anti-blocking surface is produced by, for example, sandblasting, hairline processing, mat coating, chemical etching, or the like. For example, various methods can be widely applied in the production of the anti-blocking surface.

  Further, in the above-described embodiment, the case where a support is produced by two-layer extrusion using a resin mixed with a filler and a resin not mixed with a filler has been described. An anti-blocking surface may be configured by processing one surface of the film material by using a film material made of only resin not mixed as a support material.

  In the above-described embodiment, the case where the retardation layers are laminated one by one by the transfer method has been described. However, the present invention is not limited to this. For example, in the first embodiment, the quarter-wave retardation layer, Widely applied to the case where a multi-phase retardation layer is provided on an optical film transfer body, such as when a transfer body for an optical film is composed of a laminate of two-wavelength retardation layers and this laminate is collectively transferred to an optical film. can do.

  In the above-described embodiment, the case where the quarter-wave retardation layer, the half-wave retardation layer, and the retardation layer using the positive C plate are provided on the optical film is described. However, the present invention is not limited to this. When a patterned retardation layer such as a patterned retardation film used in three-dimensional image display by a passive method is provided on an optical film, a retardation layer that imparts other retardations in the in-plane direction and the thickness direction. Can be widely applied.

DESCRIPTION OF SYMBOLS 1 Image display apparatus 2 Image display panel 3 Adhesive layer 4 Optical film 5 Linearly polarizing plate 6 1/2 wavelength phase difference layer 7 1/4 wavelength phase difference layer 8, 9 Orientation film 10, 11 Adhesion layer 15, 16 Optical film Transfer body 17 support 20 convex part

Claims (5)

An optical system comprising at least a support, an alignment film formed on the support, and a retardation layer that imparts a retardation to transmitted light, and at least the retardation layer is transferred to a transfer medium by a transfer method A transfer body for film,
The support is
The alignment film side surface is a smooth surface having an arithmetic average roughness Ra of 5 nm or more and less than 20 nm,
The transfer body for optical films whose side surface opposite to the alignment film is an anti-blocking surface. The smooth surface on the side of the alignment film is
The transfer member for an optical film according to claim 1, wherein the transfer member is a smooth surface made of a resin material into which filler is not mixed. The optical film transfer body according to claim 1, wherein the support is any one of a PET film, a TAC film, and a COP film. An optical film produced by transferring the retardation layer of the transfer member for an optical film according to any one of claims 1, 2, and 3 by a transfer method. The image display apparatus which has arrange | positioned the optical film of Claim 4 on the panel surface of an image display panel.

Images