TW201329587A - Production apparatus of optical film, method for producing optical film, and optical film - Google Patents

Abstract

It is known that a pattern is formed on a film by coating an optical alignment resin on a film and processing an exposure through a photomask. However, a boundary of an alignment pattern can not clearly be formed in a situation that an elongated film is transported while the exposure is processed in a roll-to-roll process. A production apparatus of an optical film is provided, which transported the elongated film continuously while the optical film with a plurality of alignment areas is produced, wherein the production apparatus of the optical film includes a support roll supporting the film, and an exposuring part which is disposed opposite to the support roll and exposes the photoalignment resin of the film using a polarized light through a mask, so as to produce the plurality of alignment areas in which molecular alignment directions are different from each other in the photoalignment resin. The support roll has a suppressing part which suppresses a reflection of an exposuring light.

Description

Optical film manufacturing apparatus, optical film manufacturing method, and optical film

The present invention relates to an optical film manufacturing apparatus, a method of producing an optical film, and an optical film.

A technique known in the prior art is to apply a resist on a long film, and to support a film by using a plurality of rollers while exposing through a photo mask to form a pattern on the film (for example, a patent) Document 1). It is also known that in order to more accurately form a groove for dividing a film layer provided on a solar cell or the like, a groove is formed on the film layer using a substrate supporting device, the substrate supporting device having A two-layer structure of a dielectric layer that transmits or attenuates a laser and a light absorbing layer that absorbs a laser (for example, Patent Document 2).

Patent Document 1: Japanese Patent Laid-Open No. Hei 4-97155

Patent Document 2: Japanese Patent Laid-Open No. Hei 10-27918

However, according to the method of Patent Document 1, since the region between the rolls in the film is exposed, wrinkles are generated on the film to be exposed. Therefore, although it is also considered to expose the film on the roll, at this time, since the excess reflected light from the roll is again incident on the film, there is a problem that the boundary of the alignment pattern cannot be clearly formed. Further, the method of Patent Document 2 forms a groove for dividing a thin film layer of a solar cell or the like with high precision, and has a different alignment pattern, but cannot produce an optical film in which a boundary of an alignment pattern is clearly formed.

In a first embodiment of the present invention, there is provided an optical film manufacturing apparatus for manufacturing an optical film having a plurality of alignment regions while continuously conveying an elongated film, including: a support roller, and a support is provided with optical alignment a film of the resin; and an exposure portion disposed opposite to the support roller, and exposing the photo-alignment resin of the film with polarized light through the mask, thereby exhibiting a plurality of molecular alignment directions on the photo-alignment resin An alignment region; the support roller has a roller body and a suppressing portion, and the suppressing portion suppresses reflection of exposure at the roller body.

In a second embodiment of the present invention, there is provided a method of producing an optical film comprising: a coating step of applying a photo-alignment resin on a long film and drying; and an exposing step: continuously conveying along a length direction The film exposes the photo-alignment resin with polarized light through a mask, thereby exhibiting a plurality of alignment regions having different molecular alignment directions on the photo-alignment resin; and the exposing step is to contact the support roller in the film. The step of exposing the region; the support roller includes a roller body and a suppressing portion, and the suppressing portion is provided on a surface of the roller body to suppress reflection of exposure.

In a third embodiment of the present invention, there is provided an optical film comprising: an alignment layer formed of a photo-alignment resin and having a plurality of alignment regions having mutually different molecular alignment directions; a transparent substrate supporting the alignment layer; and light The absorbing layer is disposed closer to the substrate side than the alignment layer, and absorbs wavelength light that hardens the photoalignment resin.

Further, the above-described invention does not cite all the essential features of the present invention, and sub-combinations of the feature sets may also constitute the invention.

The present invention will be described below by way of embodiments of the present invention, but the following embodiments are not intended to limit the invention as claimed. Moreover, not all of the combinations of features described in the embodiments are essential features of the invention.

Fig. 1 shows the configuration of the optical film 10 in the first embodiment. The optical film 10 is provided, for example, on the exit side of the image light of the stereoscopic display device. An example of the optical film 10 is a retardation film, and the incident image light is converted into a left-eye polarized light image and a right-eye polarized light image and output.

The optical film 10 includes a substrate 20, an alignment layer 30, and a liquid crystal layer 40. The substrate 20 is an elongated film for supporting the alignment layer 30. Substrate 20 is at least transparent to visible light, preferably optically isotropic. The substrate 20 is, for example, a Cyclo-olefin Polymer (COP) film or a Triacetyl Cellulose (TAC) film.

The alignment layer 30 is a cured photoalignment resin laminated on the surface of the substrate 20. For example, the alignment layer 30 may be such that molecules of a photo-alignment resin such as a photodecomposition type, a photodimerization type, or an optically-isotropic type are aligned and hardened by ultraviolet rays of linearly polarized light in a predetermined direction. The alignment layer 30 has a plurality of alignment regions 32 and 34 whose molecular alignment directions are different from each other. In the example shown in FIG. 1, the alignment layer 30 has a pattern in which strip-shaped alignment regions 32 and 34 extending in the Y direction are repeatedly arranged in the X direction.

The liquid crystal layer 40 is a liquid crystal compound laminated on the surface of the alignment layer 30. The liquid crystal layer 40 is composed of, for example, a nematic liquid crystal compound. The polymer of the liquid crystal compound contained in the liquid crystal layer 40 is aligned along the alignment direction of the alignment regions 32 and 34 of the alignment layer 30. Thereby, the liquid crystal layer 40 has a high score. A plurality of alignment regions 42 and 44 whose sub-orientation directions are different from each other. In the example shown in FIG. 1, the liquid crystal layer 40 has a pattern in which strip-shaped alignment regions 42 and 44 extending in the Y direction are repeatedly arranged in the X direction. The alignment direction 50 of the alignment area 42 and the alignment direction 60 of the alignment area 44 are perpendicular to each other in the XY plane. The optical film 10 composed of such a configuration may have a function of, for example, a quarter-wave plate.

FIG. 2 shows an exploded perspective view of the stereoscopic display device 1000 provided with the optical film 10. The stereoscopic display device 1000 is provided with a light source 1200, an image display portion 1300, and an optical film 10 in this order. The image display unit 1300 includes a light source side polarizing plate 1500, an image generating unit 1600, and an exit side polarizing plate 1700. When the observer observes the stereoscopic image displayed on the stereoscopic display device 1000, it is observed from the right side of the optical film 10 in FIG.

The light source 1200 is disposed on the rear side of the stereoscopic display device 1000 as seen by the observer, and in the state in which the stereoscopic display device 1000 is used (hereinafter simply referred to as "the use state of the stereoscopic display device 1000"), the white unpolarized light is directed toward the light source side. One side of the polarizing plate 1500 is irradiated.

The light source side polarizing plate 1500 is provided on the light source 1200 side in the image generating unit 1600. When the non-polarized light emitted from the light source 1200 is incident, the light source side polarizing plate 1500 transmits the linearly polarized light in which the polarization direction of the unpolarized light is parallel to the transmission axis direction, and the blocking polarization direction is parallel to the absorption axis direction. Linearly polarized light. The transmission axis direction of the light source side polarizing plate 1500 is a direction which is 45 degrees upper rightward from the horizontal direction when the observer views the stereoscopic display device 1000 as indicated by an arrow in FIG. 2 .

The image generation unit 1600 has a right eye image generation area 1620 and a left eye. Image generation area 1640. As shown in FIG. 2, the right-eye image generation area 1620 and the left-eye image generation area 1640 are areas obtained by dividing the image generation unit 1600 in the horizontal direction, and a plurality of right-eye image generation areas 1620 and left. The eye image generation regions 1640 are alternately arranged in the vertical direction.

In the use state of the stereoscopic display device 1000, a right-eye image and a left-eye image are generated in the right-eye image generation region 1620 and the left-eye image generation region 1640 of the image generation unit 1600, respectively. At this time, when the light transmitted through the light source side polarizing plate 1500 is incident on the right eye image generating area 1620 of the image generating unit 1600, the transmitted light of the right eye image generating area 1620 becomes the image light of the right eye image. (hereinafter referred to as "image light for right eye"). Similarly, when the light transmitted through the light source side polarizing plate 1500 is incident on the left eye image generating region 1640 of the image generating portion 1600, the transmitted light of the left eye image generating region 1640 becomes the image light of the image for the left eye. (hereinafter referred to as "image light for the left eye").

The right-eye image light that has passed through the right-eye image generation region 1620 and the left-eye image light that has passed through the left-eye image generation region 1640 are polarized and the direction of the transmission axis in the emission-side polarizing plate 1700, which will be described later. The same linearly polarized light. Such an image generation unit 1600 can use, for example, an LCD (Liquid Crystal Display) in which a plurality of two-dimensional small cells are provided in the horizontal direction and the vertical direction, and liquid crystals are sealed between the alignment films in the respective cells.

The exit-side polarizing plate 1700 is provided on the observer side in the image generating unit 1600. When the right-eye image light that has passed through the right-eye image generation region 1620 and the left-eye image light that has passed through the left-eye image generation region 1640 are incident, the exit-side polarizing plate 1700 polarizes the light. And transmission axis The parallel linearly polarized light is transmitted while blocking linearly polarized light whose polarization direction is parallel to the absorption axis. Here, the direction of the transmission axis in the exit-side polarizing plate 1700 is a direction in which the horizontal direction when the stereoscopic display device 1000 is viewed from the observer is shifted to the upper left by 45 degrees as indicated by the arrow in FIG. 2 .

The optical film 10 is provided on the observer side with respect to the exit-side polarizing plate 1700. The optical film 10 includes an alignment region 42 and an alignment region 44 having an alignment direction indicated by an arrow, and functions as a quarter-wave plate. As shown in FIG. 2, the position and size of the alignment region 42 and the alignment region 44 in the optical film 10 are different from the positions and sizes of the right-eye image generation region 1620 and the left-eye image generation region 1640 of the image generation portion 1600. correspond. Therefore, in the use state of the stereoscopic display device 1000, the right-eye image light transmitted through the right-eye image generation region 1620 is incident on the alignment region 42 for the right eye, and is transmitted through the left-eye image generation region 1640. The image light for the left eye is incident on the alignment region 44 for the left eye.

The alignment area 42 converts the incident right-eye image light into right-handed circularly polarized light and transmits it. Further, the alignment region 44 converts the incident left-eye image light into left-handed circularly polarized light and transmits it. Therefore, the rotational direction of the circularly polarized light of the right-eye image light transmitted through the alignment region 42 is opposite to the rotational direction of the circularly polarized light of the left-eye image light transmitted through the alignment region 44.

The left-eye filter and the right-eye filter of the polarized glasses worn by the observer selectively transmit the circularly polarized lights having mutually different rotational directions. Further, the observer can recognize the stereoscopic image by observing the images of the respective filters with the left eye and the right eye.

FIG. 3 shows the entire optical film manufacturing apparatus 100 according to the present embodiment. Composition. In the optical film manufacturing apparatus 100, a long film is continuously conveyed continuously in the direction of the arrow, that is, a so-called roll-to-roll method is used, and a plurality of alignment regions are produced by a process such as coating, drying, and exposure. Optical film 10. In the following description, the "upstream side" means the side opposite to the direction in which the film is conveyed, and the "downstream side" means the side which is the same as the direction in which the film is conveyed. The optical film manufacturing apparatus 100 of FIG. 3 includes a supply unit 108, a winding unit 126, an alignment layer applying unit 112, an alignment layer drying unit 114, an alignment processing unit 116, a liquid crystal layer coating unit 120, a liquid crystal layer drying unit 122, and a liquid crystal layer. Hardened portion 124.

The supply unit 108 is provided on the most upstream side in the transport direction of the optical film 10, and supplies the substrate 20 as a support of the optical film 10. An example of the supply unit 108 is a delivery roller. At this time, the base material 20 is wound up on the outer periphery of the feed roller, and the base material 20 is wound up by the rotation of the feed roller.

The alignment layer application portion 112 is provided on the downstream side of the supply portion 108, and a photo-alignment resin is applied to one surface of the substrate 20. The alignment layer application unit 112 may be any coating device that can apply a film to be conveyed, and is, for example, a die coater, a mirco-gravure coater, or a roll coater.

The alignment layer drying unit 114 is provided on the downstream side of the alignment layer application unit 112 and serves to dry the photo-alignment resin 28 coated on the substrate 20. The alignment layer drying unit 114 is, for example, a drying device such as an oven or a blower that can dry the film being conveyed.

The alignment processing unit 116 is provided on the downstream side of the alignment layer drying unit 114, and is linearly polarized while continuously transporting the substrate 20 in the longitudinal direction. The ultraviolet ray exposes the dried photo-alignment resin 28. Thereby, the alignment processing unit 116 forms the alignment layer 30 having a predetermined alignment pattern.

The liquid crystal layer coating portion 120 is provided on the downstream side of the alignment processing portion 116, and is used to apply the liquid crystal compound 38 on the surface of the alignment layer 30. The liquid crystal layer application unit 120 may be any coating device that can apply a film to be conveyed, and is, for example, a die coater, a micro gravure coater, or a roll coater.

The liquid crystal layer drying portion 122 is provided on the downstream side of the liquid crystal layer applying portion 120, and serves to dry the liquid crystal compound 38 coated on the alignment layer 30. The liquid crystal layer drying unit 122 is, for example, a drying device such as an oven or a blower that can dry the film being conveyed.

The liquid crystal layer curing portion 124 is provided on the downstream side of the liquid crystal layer drying portion 122, and is used to cure the liquid crystal compound 38 after drying by irradiating ultraviolet rays. Thereby, the liquid crystal layer hardened portion 124 forms the liquid crystal layer 40 aligned along the alignment layer 30. When the liquid crystal compound is thermosetting, the liquid crystal layer hardening portion 124 may be a heating device such as an oven.

The take-up portion 126 is provided on the most downstream side of the optical film manufacturing apparatus 100, and is used to take up the optical film 10 which is formed after the upstream stages. The take-up portion 126 is, for example, a take-up roll. The optical film 10 is wound around the outer circumference of the winding portion 126 by the rotation of the winding portion 126.

The supply unit 108 rotates in synchronization with the winding unit 126, and at least one of them has a rotation driving device such as a motor. When there is a rotary drive on one of the rollers, the roller having the rotary drive actively drives the transport of the film, and the roller without the rotary drive follows the roller having the rotary drive Driven by rotation. When both of the rollers have the rotation driving means, the supply portion 108 and the winding portion 126 synchronize the delivery speed with the take-up speed to smoothly convey the film. In addition to this, the supply unit 108 and the winding unit 126 are not synchronized, and it is also possible to rotate at an independent rotation speed. Further, the optical film manufacturing apparatus 100 may have another film driving device such as a roller with a motor in the film transport path.

FIG. 4 shows the configuration of the alignment processing unit 116 according to the present embodiment. The alignment processing unit 116 exposes the photo-alignment resin 28 applied on the substrate 20 continuously supplied in the direction of the arrow. The alignment processing unit 116 includes a support roller 130, a conveyance roller 132, an exposure unit 134, an exposure unit 136, and a mask 138.

The support roller 130 is rotatable and supports the base material 20 provided with the photo-alignment resin 28 supplied from the supply portion 108. The support roller 130 brings tension to the film by bending the film transport path along its surface. Thereby, the support roller 130 prevents the film from being displaced in the width direction, and also prevents wrinkles and the like from occurring in the contact area with the film. In addition, the support roller 130 also suppresses wrinkles in the film between the rollers.

The conveyance roller 132 is rotatable, and supports the base material 20 from the directional layer drying part 114, and conveys it to the support roll 130. Moreover, the conveyance roller 132 is also used to convey the base material 20 to the liquid-crystal layer application part 120.

The exposure portions 134 and 136 are disposed to face the support roller 130. The exposed portions 134 and 136 output linearly polarized light having mutually different polarization directions, and the photo-alignment resin on the substrate 20 is exposed through the mask 138, whereby a plurality of alignment regions having different alignment directions can be expressed.

The mask 138 is disposed on the exposure portion 134 and the exposure portion 136 and the substrate 20 between. The mask 138 blocks a part of the polarized light from the exposure portion 134 and the exposure portion 136, and partially transmits the polarized light.

Fig. 5 is a plan view showing the mask 138 of the present embodiment. Arrow 148 indicates the transport direction of the film during exposure, and arrow 149 indicates the width direction of the elongated film. The mask 138 is provided with a first exposure region 140 provided with a plurality of openings 142 and a second exposure region 144 provided with a plurality of openings 146. The linearly polarized light outputted from the exposure portion 134 is incident on the first exposure region 140, and the linearly polarized light output from the exposure portion 136 is incident on the second exposure region 144.

The opening 142 corresponds to the alignment region 34 of the alignment layer 30 and has the same size as the width of the alignment region 34 in the width direction of the film. The opening 146 corresponds to the alignment region 32 of the alignment layer 30 and has the same size as the width of the alignment region 32 in the width direction of the film. The opening 146 is away from the opening 142 in the conveying direction of the film, and is located between the openings 142 in the width direction of the film. Further, as indicated by the arrow in the opening, the opening 142 and the opening 146 transmit linearly polarized light having mutually different polarization directions. Thereby, the alignment processing unit 116 of the present embodiment can form the alignment layer 30 in which the strip-shaped alignment regions 32 and 34 are seamlessly provided.

FIG. 6 is a schematic cross-sectional view showing an exposed portion of the alignment processing unit 116 according to the present embodiment. Fig. 6 corresponds to the portion A surrounded by the broken line of Fig. 4. The arrows indicate the direction of illumination of the exposure 154 through the mask 138. The support roller 130 includes a roller body 150 and a restraining portion 152 provided on the surface of the roller body 150.

The roller body 150 is a cylindrical roller, and is made of, for example, a metal such as stainless steel. The restraining portion 152 is formed on the outer peripheral portion of the roller body 150 for suppressing entry The reflection of the exposure 154.

As shown in FIG. 6, the exposure portion 136 exposes a region of the substrate 20 coated with the photo-alignment resin 28 in contact with the support roller 130. By this, since the film is exposed in a state in which the film is stretched in the width direction, the alignment processing unit 116 of the present embodiment can prevent wrinkles and the like from occurring on the film.

Fig. 7 is an enlarged cross-sectional view showing the support roller 130 of the present embodiment. Fig. 7 corresponds to the portion B surrounded by the broken line in Fig. 6. In this embodiment, the restraining portion 152 is an exposure absorbing layer provided on the surface of the roller body 150. The exposure absorbing layer serves to absorb the exposure 154, thereby suppressing reflection of the exposure 154 located on the surface of the support roller 130.

The exposure absorbing layer is, for example, a layer composed of a black paint. The layer composed of the black paint can be formed, for example, by coating, spraying, thermally bonding, or vapor-depositing a black paint on the surface of the support roll 130. The black paint is a paint in which black pigment or the like is dispersed. The black paint can be formed to have a uniform film thickness on the outer circumference of the roller body 150, and it is possible to prevent the substrate 20 during conveyance from slipping. Further, the suppressing portion 152 may further have a resin for preventing abrasion or the like on the outer periphery of the black paint, so that abrasion of the black paint can be prevented. Further, in addition to this, the exposure absorption layer may be a layer composed of a colored or colorless ultraviolet absorbing resin or the like.

Thereby, the suppressing portion 152 can prevent the photo-alignment resin 28 from being aligned by the reflected light of the exposure 154, thereby causing a phenomenon that the boundary of the alignment pattern of the alignment layer 30 is not clear. Therefore, the alignment processing unit 116 of the present embodiment can obtain the alignment layer 30 having the alignment pattern of the sharp boundary.

Further, by making the boundary of the alignment pattern of the alignment layer 30 clear, the boundary of the alignment pattern of the liquid crystal layer 40 formed on the surface of the alignment layer 30 is also made clear. Therefore, when the optical film 10 manufactured by the optical film manufacturing apparatus 100 is provided in the stereoscopic display device, it is possible to display a high-quality stereoscopic image in which crosstalk of the left and right parallax images is small. In order to sufficiently achieve this effect, it is preferable to set the reflectance of the support roller 130 with respect to ultraviolet rays to 5% or less.

The machine for measuring the reflectance was a spectrophotometer U-4100 (manufactured by Hitachi High-Technologies Corporation). The wavelength light used for the measurement was a wavelength light which the light-aligning resin was able to receive light, and the reflectance when the incident angle was 5 degrees was measured. The reflectance here refers to the reflectance (relative reflectance) of the measured sample relative to the reference sample plate. This is taken as the reflectance of the support roller 130 with respect to ultraviolet rays. Although the reference sample plate uses a plate made of barium sulfate, plates of other materials can also be used. The measurement sample was a glass plate including a light absorbing layer provided on a support roller. Further, in the present measurement, in order to obtain the reflectance of the ultraviolet region, a high-sensitivity integrating sphere was attached to the spectrophotometer and then measured.

FIG. 8 is an enlarged cross-sectional view showing the support roller 130 according to the first modification of the embodiment. Fig. 8 corresponds to the portion B surrounded by the broken line of Fig. 6. In the present modification, the restraining portion 152 is an exposure interference layer provided on the surface of the roller body 150. The exposure interference layer interferes in such a manner that the exposure 154 reflected at the interface becomes weak, thereby suppressing reflection of the exposure 154 on the surface of the support roller 130.

The exposure interference layer is, for example, an oxide having a film thickness of 1/4 exposure wavelength. Metal multilayer film. In addition, the exposure interference layer may be a single-layer oxide metal film, a single-layer or a multilayer resin film, or the like. The exposure interference layer can be formed to have a uniform film thickness on the outer circumference of the roller body 150, so that the reflection of the exposure 154 can be surely suppressed, and the sliding of the substrate 20 during transportation can be prevented.

Fig. 9 is an enlarged cross-sectional view showing the support roller 130 according to a second modification of the embodiment. Figure 9 corresponds to the portion B surrounded by the broken line of Figure 6. In the present modification, the restraining portion 152 is an exposure scattering layer provided on the surface of the roller body 150. The suppression portion 152 scatters the exposure 154 by exposing the scattering layer, thereby suppressing reflection of the exposure 154 on the surface of the support roller 130.

The exposure scattering layer can be formed, for example, of a resin in which fine particles or the like that scatter light is dispersed. The resin in which fine particles or the like are dispersed is formed on the outer circumference of the roll main body 150 with a uniform film thickness, thereby preventing the sliding of the base material 20 during conveyance. In addition to this, the exposure scattering layer may be irregularities formed by texture processing or the like on the surface of the roller body 150.

In FIGS. 7 to 9, the case where the suppression portion 152 is one of the exposure absorption layer, the exposure interference layer, and the exposure diffusion layer has been described. However, the suppression portion 152 may be an exposure absorption layer or an exposure interference. Two or more layers and an exposure scattering layer are laminated. For example, the suppression portion 152 may be composed of an exposure interference layer or an exposure scattering layer provided on the exposure absorption layer and the exposure absorption layer.

(a) to (c) of FIG. 10 and (d) to (f) of FIG. 11 show a method of manufacturing the optical film 10 according to the present embodiment. The method for producing an optical film according to the present embodiment can be carried out by the optical film manufacturing apparatus 100 shown in Fig. 3 .

First, in (a) of FIG. 10, the supply portion 108 continuously supplies strips. The substrate 20 of the TAC film. Here, a light absorbing layer, an antireflection layer, or an antiglare layer may be provided in advance on one side or both sides of the substrate 20. Further, the substrate 20 is also replaced with a COP film instead of the TAC film.

Then, in the (b) of FIG. 10, the alignment layer applying portion 112 applies the photo-alignment resin 28 in the form of a liquid coating material on one surface thereof while continuously conveying the substrate 20 in the longitudinal direction. Further, the alignment layer drying unit 114 continuously transports the substrate 20 in the longitudinal direction while drying the photo-alignment resin 28 to remove the solvent.

Then, in (c) of FIG. 10, the alignment processing unit 116 performs the first exposure of a part of the photo-alignment resin 28 through the first exposure region 140 of the mask 138 by linearly polarized light parallel to the Y direction. The first exposure is, for example, ultraviolet ray irradiation of linearly polarized light having a wavelength of 280 to 340 nm at an intensity of 20 to 200 mW/cm ² . The exposed region in the photo-alignment resin 28 exhibits an alignment region 34 aligned in a direction parallel to the Y direction and is hardened.

In the first exposure process, the alignment processing unit 116 exposes the region in contact with the support roller 130 in the film while continuously conveying the substrate 20 on the support roller 130 including the suppression portion 152. Thereby, wrinkles and the like are prevented from occurring on the film during exposure. In addition, since the suppression portion 152 suppresses the reflection of the exposure 154 on the surface of the support roller 130, it is possible to prevent the blur of the alignment pattern boundary caused by the reflected light of the exposure 154.

Then, in (d) of FIG. 11, the alignment processing unit 116 uses the linearly polarized light parallel to the X direction, and passes through the second exposure region 144 of the mask 138 to the unexposed region of the photoalignment resin 28. Two exposures. In the linearly polarized light of the second exposure, ultraviolet rays having the same wavelength and the same intensity as the first exposure can be used. In the exposed region of the photo-alignment resin 28, the alignment region 32 aligned in the direction parallel to the X direction appears to be hardened.

In the second exposure process, the alignment processing unit 116 irradiates the region where the support roller 130 and the substrate 20 are in contact with each other while continuously conveying the substrate 20 to the support roller 130. Thereby, wrinkles and the like are prevented from occurring on the film during exposure. Further, in the second exposure, the suppressing portion 152 of the support roller 130 can also prevent the unclear alignment pattern caused by the reflected light of the exposure 154. Thereby, according to the method of manufacturing an optical film of the present embodiment, the reflection of the exposure is prevented by the suppression portion 152 in any of the two exposure processes, so that the boundary formed by the alignment region 32 and the alignment region 34 can form a clear alignment. Patterned alignment layer 30.

Then, in (e) of FIG. 11, the liquid crystal layer applying portion 120 applies an ultraviolet curable or thermosetting liquid crystal compound 38 to the alignment layer 30. Then, the liquid crystal layer drying unit 122 dries the liquid crystal compound 38 applied on the alignment layer 30. The liquid crystal compound 38 forms an alignment pattern having a clear boundary with the alignment region 32 and the alignment region 34 of the alignment layer 30, and is aligned.

Then, the liquid crystal layer 38 is cured by irradiation of ultraviolet rays by the liquid crystal layer curing portion 124 of (f) of FIG. 11 to form the liquid crystal layer 40 having the alignment regions 42 and 44. The ultraviolet ray to be applied to the liquid crystal compound 38 may be the same as or different from the wavelength of the ultraviolet ray irradiated to the photo-alignment resin in (c) of FIG. 10 and (d) of FIG. 11 . In addition, LCD The layer hardened portion 124 can also harden the liquid crystal compound 38 by heating.

Thus, the optical film 10 having the liquid crystal layer 40 having a clear alignment pattern boundary is obtained by the manufacturing method shown in FIGS. 10(a) to 11(f). The obtained optical film 10 is taken up by the winding portion 126. Thereafter, the elongated optical film 10 can be cut into an appropriate length suitable for use in a display device or the like.

(a) and (b) of FIG. 12 show photographs in which the alignment pattern of the liquid crystal layer 40 of the optical film 10 is observed using a polarizing microscope. (a) of FIG. 12 is a photograph of an alignment pattern of the liquid crystal layer 40 of the optical film 10 produced by the support roller 130 containing no suppression portion 152 observed using a polarizing microscope. The observed alignment pattern is formed substantially in a strip shape by the first alignment region 300 and the second alignment region 310. However, minute irregularities are generated between the first alignment region 300 and the second alignment region 310, and the boundary is not clear.

(b) of FIG. 12 is a photograph of an alignment pattern of the liquid crystal layer 40 of the optical film 10 produced by the support roller 130 including the suppression portion 152 observed using a polarizing microscope. There is no unevenness between the first alignment region 300 and the second alignment region 310 observed, and the boundary is clear.

FIG. 13 shows the configuration of the optical film 12 according to the third modification of the embodiment. The optical film 12 is the same as the optical film 10 shown in FIG. 1 except that the light absorbing layer 70 is provided closer to the substrate 20 than the alignment layer 30.

The light absorbing layer 70 is a layer for absorbing light of a wavelength, for example, ultraviolet light, which cures the photo-alignment resin 28 forming the alignment layer 30. The light absorbing layer 70 may be formed of a hard coating material, for example, a polymer mainly composed of a polyfunctional monomer containing a (meth) acryloxy group.

The light absorbing layer 70 absorbs the exposure 154 that transmits the light-aligning resin 28 and the exposure 154 that is reflected by the support roller 130 during exposure of the photo-alignment resin 28, so that an alignment pattern having a sharp boundary can be formed thereon. Alignment layer 30. In addition, since the light absorbing layer 70 can transmit visible light, the optical characteristics of the optical film 12 are not impaired. Thereby, the stereoscopic display device in which the optical film 12 is provided on the image output side can display a high-quality stereoscopic image with less crosstalk. Further, the light absorbing layer 70 may not be provided between the substrate 20 and the alignment layer 30, but may be provided on a surface of the two faces of the substrate 20 opposite to the alignment layer 30.

FIG. 14 shows the configuration of the optical film 14 according to the fourth modification of the embodiment. The optical film 14 is the same as the optical film 12 shown in FIG. 13 except that the antireflection layer 80 is further provided on the surface of the substrate 20 opposite to the side on which the alignment layer 30 is provided. The reflection preventing layer 80 suppresses reflected light by performing light interference. The anti-reflection layer 80 is formed of a resin having a lower refractive index than the substrate 20 to have a film thickness of 1/4 visible light wavelength (for example, 550 nm). As the resin having a low refractive index, for example, an ultraviolet curable resin obtained by dispersing cerium oxide particles having an average particle diameter of 0.5 nm to 200 nm which is reduced in refractive by an internal hollow structure can be used.

In addition to the visible light, the anti-reflection layer 80 causes the ultraviolet rays incident through the photo-alignment resin 28 during the exposure of the photo-alignment resin 28 to reflect and interfere at the layer interface, thereby preventing the substrate 20 and the support roller 130 from being disposed. The exposure 154 reflected at the interface is incident on the photo-alignment resin 28. As described above, according to the present modification, the light absorbing layer 70 and the reflection preventing layer 80 contribute to the sharpening of the boundary of the alignment pattern of the alignment layer 30.

In addition, the optical film 14 may have an anti-glare layer instead of the anti-reflection layer 80. The anti-glare layer is formed of a resin or the like in which fine particles or the like which scatter light is dispersed, and is used for light-scattering the exposure 154 incident during exposure. Thereby, since the anti-glare layer can suppress the reflected light of the exposure 154 on the support roller 130, the same effect as the anti-reflection layer 80 can be obtained.

In addition, the optical film 14 may be further provided with another light absorbing layer instead of the reflection preventing layer 80. The other light absorbing layer may be the same as the light absorbing layer 70 described in the third modification.

Tables 1 to 3 show Comparative Examples 1 to 8 and Examples 1 to 13 of the present embodiment. The column of "film" in the table indicates a film configuration in which the photo-alignment resin 28 is applied and the alignment layer 30 is formed in each of the comparative examples and the examples. The TAC corresponds to a TAC film respectively serving as each of the substrates 20, LR corresponds to the anti-reflection layer 80, AG corresponds to the anti-glare layer, HC corresponds to the light absorbing layer 70, and the like. The photo-alignment resin 28 is applied to the film (alignment layer) side. For example, the (alignment layer)/HC/TAC/AG of Comparative Example 5 means that an anti-glare layer is provided on one surface of the TAC film, and a light absorbing layer is provided on the surface of the TAC film opposite to the anti-glare layer, on the light absorbing layer. The meaning of the photo-alignment resin 28 is applied.

Thereafter, the film is supported by the support roller 130, and the photo-alignment resin is exposed to form the alignment layer 30. Here, "Yes" in the column of "exposure absorbing layer" in the table indicates that the support roller 130 includes the exposure absorbing layer as the suppression portion 152, and "None" indicates that the support roller 130 does not include the suppression portion 152. The "between support rolls" in the column of "exposure position" means that the area stretched between the two support rolls 130 in the film is exposed (exposure between rolls), and the "on the support roll" means the support roll in the film. The 130-contact area is exposed (back roll exposure).

Thereafter, the liquid crystal layer 40 was applied onto the alignment layer 30, and dried and ultraviolet-cured to obtain an optical film of each of Comparative Examples and Examples. Next, the optical film obtained in each of the comparative examples and the examples was cut into a predetermined size so that the liquid crystal layer 40 was placed on the upper surface, and the polarizing plate was superposed on the polarizing plate, and the wrinkles and the sharpness of the boundary portion of the alignment pattern were observed. The angle is used to evaluate each optical film.

"X" in the column "Occurrence of wrinkles" in the table indicates that wrinkles occurred on the produced optical film, and "○" indicates that wrinkles did not occur. "X" in the column of "clearness of the boundary portion" indicates that unevenness exceeding 10 μm from the average line is generated at the boundary of the alignment pattern of the liquid crystal layer 40, and "△" indicates that unevenness of 5 to 10 μm is generated, "○" It indicates that unevenness of 5 μm or less was generated. The smaller the unevenness is, the more the alignment error can be ensured when the optical film is aligned to the image display unit 1300 of the LCD. For example, when the unevenness is 10 μm or less, the image display portion 1300 having a black matrix having a width of 30 μm is allowed to have a bonding position error of 10 μm or more, and if the unevenness is 5 μm or less, 20 μm or more is allowed. Fit error. Further, when the optical film is bonded, the optical film is stretched and contracted by the bonding stress, but the smaller the unevenness, the more the influence of the expansion and contraction can be alleviated. When the unevenness is 5 μm or less, unevenness is hardly observed by the microscope.

As shown in Table 1, in Comparative Examples 1 to 7 in which the photo-alignment resin 28 was exposed between the support rolls 130, wrinkles were formed on the produced optical film. Further, in Comparative Example 8 in which the photo-alignment resin 28 was exposed on the support roller 130 containing no suppression portion 152, the boundary of the alignment pattern of the liquid crystal layer 40 of the produced optical film was not clear.

Fig. 15 is a photograph showing the boundary of the alignment pattern of the liquid crystal layer 40 of the optical film obtained in Comparative Example 8 which was magnified 500 times by an optical microscope and observed by a polarizing microscope. As shown in the figure, irregularities are generated between the alignment patterns of the liquid crystal layer 40, so that the boundary is not clear. The unevenness at the boundary of the alignment pattern is more than 10 μm from the average line (thick line in the figure). The average line is, for example, the middle between the convex reference line which is disposed in the convex portion which is the most prominent in the unevenness and which is parallel to the boundary line of the alignment pattern and the concave reference line which is disposed in the concave portion which is the most depressed in the unevenness and which is parallel to the boundary line of the alignment pattern. line.

Further, when the optical film is used for a stereoscopic display device, in order to sufficiently suppress crosstalk as much as possible, it is preferable that the unevenness of the boundary between the plurality of alignment regions starting from the average line is within 10 μm, more preferably within 5 μm.

On the other hand, in Examples 1 to 13 in which the photo-alignment resin 28 was exposed on the support roller 130, no wrinkles were formed on the optical film produced. Further, in Examples 1 to 6 in which one or more of the light absorbing layer, the antireflection layer, and the antiglare layer were provided on the substrate 20, and Examples 7 to 13 manufactured by using the support roller 130 including the exposure absorption layer, The unevenness of the alignment pattern of the liquid crystal layer 40 of the produced optical film did not occur more than 10 μm.

In particular, by providing one or more of the light absorbing layer, the antireflection layer, and the antiglare layer on the substrate 20, and further using the optical films of Examples 8 to 13 manufactured by using the support roller 130 containing the exposure absorbing layer, the liquid crystal is made. The boundary pattern of the alignment pattern of the layer 40 was excellent in sharpness, and no unevenness was observed at the boundary.

Figure 16 shows the optical obtained in Example 10 by a polarizing microscope. A photograph when the boundary of the alignment pattern of the liquid crystal layer 40 of the film was observed. As shown in the figure, there is almost no unevenness between the alignment patterns of the liquid crystal layer 40, and the boundary is extremely clear.

Although the embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various changes and modifications can be added to the above embodiments. It is apparent from the description of the claims that such modified and improved embodiments are also included in the technical scope of the present invention.

It should be noted that the order of execution of the processes, the procedures, the steps, the stages, and the like in the devices, the systems, the procedures, and the methods in the claims, the description, and the drawings are as long as "early", " Earlier than "etc., or as long as the previously processed output is not used in later processing, it can be implemented in any order. In the claims, the description and the figures The operation flow has been described using "first", "then", etc. for convenience, but it does not mean that it must be implemented in this order.

10‧‧‧Optical film

12‧‧‧Optical film

14‧‧‧Optical film

20‧‧‧Substrate

28‧‧‧Photoalignment Resin

30‧‧‧Alignment layer

32‧‧‧Alignment area

34‧‧‧Alignment area

38‧‧‧Liquid Crystal Compounds

40‧‧‧Liquid layer

42‧‧‧Alignment area

44‧‧‧Alignment area

50‧‧‧Orientation direction

60‧‧‧Alignment direction

70‧‧‧Light absorbing layer

80‧‧‧reflection prevention layer

100‧‧‧Optical film manufacturing equipment

108‧‧‧Supply Department

112‧‧‧Alignment layer coating department

114‧‧‧Alignment layer drying department

116‧‧‧Alignment Processing Department

120‧‧‧Liquid layer coating department

122‧‧‧Liquid layer drying department

124‧‧‧Liquid layer hardening department

126‧‧‧Winding Department

130‧‧‧Support roller

132‧‧‧Transport roller

134, 136‧ ‧ exposure department

138‧‧‧ mask

140‧‧‧First exposure area

142‧‧‧ openings

144‧‧‧second exposure area

146‧‧‧ openings

148‧‧‧ arrow

149‧‧‧ arrow

150‧‧‧roll body

152‧‧‧Suppression Department

154‧‧‧ exposure

300‧‧‧First alignment area

310‧‧‧Second alignment area

1000‧‧‧ Stereo display device

1200‧‧‧Light source

1300‧‧‧Image Display Department

1500‧‧‧Light source side polarizer

1600‧‧‧Image Generation Department

1620‧‧‧Right eye image generation area

1640‧‧‧Left eye image generation area

1700‧‧‧Outlet side polarizer

Part A, B‧‧‧

FIG. 1 shows the configuration of an optical film 10 according to the first embodiment.

FIG. 2 is an exploded perspective view showing the stereoscopic display device 1000 in which the optical film 10 is provided.

FIG. 3 shows the overall configuration of the optical film manufacturing apparatus 100 according to the present embodiment.

FIG. 4 shows the configuration of the alignment processing unit 116 according to the present embodiment.

FIG. 5 is a plan view showing the mask 138 of the present embodiment.

FIG. 6 is a schematic cross-sectional view showing an exposure portion of the alignment processing unit 116 according to the present embodiment.

FIG. 7 is an enlarged cross-sectional view showing the support roller 130 according to the embodiment.

FIG. 8 is an enlarged cross-sectional view showing the support roller 130 according to the first modification of the embodiment.

FIG. 9 is an enlarged cross-sectional view showing the support roller 130 according to a second modification of the embodiment.

FIG. 10 shows a method of manufacturing the optical film 10 according to the embodiment.

FIG. 11 shows a method of manufacturing the optical film 10 according to the embodiment.

FIG. 12 is a photograph showing an alignment pattern of the liquid crystal layer 40 of the optical film 10 observed by a polarizing microscope.

FIG. 13 shows a configuration of an optical film 12 according to a third modification of the embodiment.

FIG. 14 shows a configuration of an optical film 14 according to a fourth modification of the embodiment.

FIG. 15 is a photograph showing a boundary of an alignment pattern of the liquid crystal layer 40 of the optical film obtained in Comparative Example 8 by a polarizing microscope.

FIG. 16 is a photograph showing the boundary of the alignment pattern of the liquid crystal layer 40 of the optical film obtained in Example 10 by a polarizing microscope.

20‧‧‧Substrate

28‧‧‧Photoalignment Resin

30‧‧‧Alignment layer

130‧‧‧Support roller

136‧‧‧Exposure Department

138‧‧‧ mask

150‧‧‧roll body

152‧‧‧Suppression Department

154‧‧‧ exposure

Part A, B‧‧‧

Claims (12)

An optical film manufacturing apparatus for manufacturing an optical film having a plurality of alignment regions while continuously conveying a long film, comprising: a support roller supporting the film provided with a photo-alignment resin; and an exposure portion, Opposite the support roller, and exposing the photo-alignment resin of the film with polarized light through a mask, thereby exhibiting the molecular alignment directions on the photo-alignment resin a plurality of alignment regions, the support roller having a roller body and a suppressing portion for suppressing reflection of the exposure at the roller body. The optical film manufacturing apparatus according to claim 1, wherein the suppressing portion is an exposure absorbing layer that absorbs the exposure to suppress reflection of the polarized light. The optical film manufacturing apparatus according to claim 1, wherein the suppressing portion is an exposure interference layer that interferes with the exposure to suppress the exposure and reflection. The optical film manufacturing apparatus according to claim 1, wherein the suppressing portion is an exposure scattering layer that scatters the exposure to suppress the exposure and reflection. A method for producing an optical film, comprising: a coating step of: coating a photo-alignment resin on a long film and drying; and an exposing step of continuously transferring the film along a length direction while polarizing through a mask Light exposure of the photo-alignment resin, thereby The plurality of alignment regions in which the molecular alignment directions are different from each other are exhibited on the photo-alignment resin, and the exposing step is a step of exposing a region of the film that is in contact with the support roller, the support roller including the roller body And a suppressing portion that is provided on a surface of the roller body to suppress reflection of the exposure. The method for producing an optical film according to claim 5, wherein the suppressing portion is an exposure absorbing layer that absorbs the exposure to suppress the exposure and reflection. The method for producing an optical film according to claim 5, wherein the suppressing portion is an exposure interference layer that interferes with the exposure to suppress the exposure and reflection. The method for producing an optical film according to claim 5, wherein the suppressing portion is an exposure scattering layer that scatters the exposure to suppress the exposure and reflection. An optical film produced by the production method as described in claim 5 of the patent application. An optical film comprising: an alignment layer formed of a photo-alignment resin and having a plurality of alignment regions having mutually different molecular alignment directions; a transparent substrate supporting the alignment layer; and a light absorbing layer disposed at a ratio The alignment layer is closer to the substrate side and absorbs wavelength light that hardens the photoalignment resin. An optical film having multiple alignments with different molecular alignment directions a region, wherein: at a boundary between the plurality of alignment regions, the unevenness from the average line is within 10 μm. The optical film according to claim 11, wherein the unevenness of the average line is within 5 μm at a boundary between the plurality of alignment regions.