JP2016148692A - Manufacturing method of optical film, measurement method of optical film, take-up body of optical film, and laminate of optical film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a reduction in dimensional accuracy due to absorption of moisture by a substrate, regarding an optical film, such as a pattern phase difference film used for an image display device that displays three-dimensional images in a passive method.SOLUTION: A manufacturing method of an optical film comprises: an alignment layer manufacturing step of manufacturing an alignment layer 3 on a substrate 2 formed of a long transparent film material; and a phase difference layer manufacturing step of manufacturing a phase difference layer 4 on the alignment layer 3 to manufacture an optical film raw fabric 7, and a moisture-proof film 12 and the optical film raw fabric 7 are laminated and taken up in a roll to manufacture a take-up body 15 of the optical film raw fabric 7.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an optical film such as a pattern retardation film according to a passive three-dimensional image display.

  In recent years, an image display device that displays a three-dimensional image by a passive method has been provided. Here, FIG. 11 is a schematic view showing a passive type image display device using a liquid crystal display panel. The passive-type image display apparatus sequentially assigns pixels of the liquid crystal display panel that are continuous in the vertical direction or the horizontal direction (vertical direction in the example of FIG. 11) for the right eye and the left eye. Driving with the image data for the left eye, thereby displaying the image for the right eye and the image for the left eye simultaneously. In addition, a pattern retardation film is arranged on the panel surface (viewer side) of the liquid crystal display panel so that the light emitted from the right-eye pixel and the left-eye pixel is linearly polarized light having different directions for the right-eye and left-eye. Convert to As a result, in the passive method, glasses equipped with corresponding polarizing filters are worn, and a right-eye image and a left-eye image are selectively provided to the viewer's right and left eyes, respectively, and a three-dimensional image is displayed. To do.

  Therefore, in the pattern retardation film, two types of band-like regions in which the slow axis direction (direction in which the refractive index is maximized) are orthogonal to each other are sequentially formed corresponding to the setting of the pixels in the liquid crystal display panel. Here, as the slow axis direction of the adjacent belt-like regions, a combination of +45 degrees and −45 degrees, or 0 degrees and +90 degrees with respect to the horizontal direction is usually employed. In the example of FIG. 11, the long side direction of the screen is shown as the horizontal direction in accordance with the name in the normal image display apparatus.

  Conventionally, the pattern retardation film according to this passive method is used to transfer a substrate made of a film material such as TAC (triacetyl cellulose) which is a transparent film material with small optical anisotropy, while providing a photo-alignment film and a retardation layer. It is produced by producing sequentially.

  When the dimensional accuracy of the pattern phase difference film is lowered, the relative position accuracy with respect to the corresponding pixel is lowered, so that crosstalk occurs and the image quality is remarkably deteriorated. Here, crosstalk is a phenomenon in which light emitted from the image display panel that should be supplied to the right and left eyes originally leaks to the left and right eyes. For this reason, conventionally, in the manufacturing process of the pattern phase difference film, as shown in FIG. 12, the wound body R of the pattern phase difference film original roll wound up in a roll shape is made of 2 with a polypropylene film PP and an aluminum foil AL. It is packed heavyly, thereby preventing a decrease in dimensional accuracy due to moisture absorption of the base material.

  Regarding such a pattern retardation film, Patent Documents 1 to 3 propose a method for reducing a decrease in dimensional change by devising a base material.

  By the way, even with the double packaging described above with reference to FIG. 12, the pattern retardation film still has a practically insufficient problem with respect to a decrease in dimensional accuracy due to moisture absorption of the base material. As disclosed in Patent Documents 1 to 3 as one method for solving this problem, it is conceivable to devise a base material. However, in this method, a highly versatile film material cannot be applied to the base material. There is.

JP 2014-121790 A JP 2013-29552 A JP 2013-218058 A

  This invention is proposed in view of such a situation, and it aims at reducing the fall of a dimensional accuracy regarding optical films, such as a pattern phase difference film.

  This inventor repeated earnest examination in order to solve the subject mentioned above. As a result, the present invention was completed based on the idea that the moisture absorption of the base material is reduced by adopting a form in which the moisture-proof films are alternately laminated.

  Specifically, the present invention provides the following.

(1) An alignment layer preparation step of preparing an alignment layer on a substrate made of a long transparent film material;
A retardation layer preparation step of preparing a retardation layer on the alignment layer to prepare an optical film original fabric,
A method for producing an optical film, in which a moisture-proof film and the optical film original are stacked and wound to produce a wound body of the optical film original.

  According to (1), the moisture-proof film and the optical film raw material are sequentially and alternately laminated in the radial direction, so that it is possible to strictly prevent moisture, thereby reducing moisture absorption of the base material. A reduction in dimensional accuracy due to moisture absorption of the material can be prevented.

(2) an alignment layer preparation step of preparing an alignment layer on a substrate made of a transparent film material;
A retardation layer production step of producing an optical film by producing a retardation layer on the alignment layer,
A method for producing an optical film, wherein a moisture-proof film and the optical film are alternately laminated in order to produce a laminate of optical films.

  According to (2), the moisture-proof film and the optical film are alternately laminated in the laminating direction, whereby it is possible to strictly prevent moisture, thereby reducing the moisture absorption of the substrate, A decrease in dimensional accuracy due to moisture absorption can be prevented.

(3) From the wound body of the optical film original in the form of a long transparent film material, the optical film original is pulled out and cut to produce a test piece of the optical film original,
Winding the laminate of the test piece and moisture-proof film to produce a wound body of the optical film original fabric according to the test piece,
The measuring method of the optical film which measures the dimension of the said optical film original fabric from the winding body of the optical film original fabric which concerns on the said test piece.

  According to (3), the moisture-proof film and the optical film original fabric are laminated alternately and sequentially in the radial direction, so that the moisture can be strictly controlled and the optical film original fabric can be used for the test. Various measurements can be performed while preventing a decrease in accuracy.

  (4) A wound body of an optical film original that is wound in a state in which a moisture-proof film is laminated on an optical film original provided with an orientation layer and a retardation layer on a substrate made of a long transparent film material.

  According to (4), the moisture-proof film and the optical film raw material are sequentially and alternately laminated in the radial direction, so that it is possible to strictly prevent moisture, thereby reducing moisture absorption of the base material. A reduction in dimensional accuracy due to moisture absorption of the material can be prevented.

  (5) A laminated body of optical films formed by alternately laminating optical films made of single sheets provided with an orientation layer and a retardation layer on a substrate made of a transparent film material, and moisture-proof films.

  According to (5), the moisture-proof film and the optical film raw material are sequentially and alternately laminated in the thickness direction, so that it is possible to strictly prevent moisture, thereby reducing moisture absorption of the base material. A reduction in dimensional accuracy due to moisture absorption of the material can be prevented.

  According to the present invention, it is possible to further prevent a decrease in legal accuracy due to moisture absorption.

It is a figure which shows the pattern phase difference film which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing process of the pattern phase difference film of FIG. It is a figure where it uses for description of winding of a pattern phase difference film original fabric. It is a figure which shows the winding body of a pattern phase difference film original fabric. 10 is a chart showing measurement results of Comparative Example 1. 10 is a chart showing measurement results of Comparative Example 2. It is a chart which shows the measurement result concerning a 1st embodiment. It is a chart of a measurement result of a comparative example and an example. It is a figure where it uses for description of the laminated body of the pattern phase difference film and moisture-proof film by a sheet | seat. It is a figure where it uses for description of a test piece. It is a figure where it uses for description of a pattern phase difference film. It is a figure where it uses for description of the conventional packing method.

[First Embodiment]
(Image display device)
FIG. 1 is a view showing a pattern retardation film according to the first embodiment of the present invention. In the image display device according to this embodiment, the pixels of the liquid crystal display panel that are continuous in the vertical direction (the left-right direction in FIG. 1) sequentially display the right-eye pixel for displaying the right-eye image and the left-eye image. They are distributed to the left-eye pixels to be displayed, and are driven by right-eye and left-eye image data, respectively. As a result, the image display device alternately divides the display screen into a band-like region for displaying an image for the right eye and a band-like region for displaying an image for the left eye. Display at the same time. In this image display device, the pattern phase difference film 1 shown in FIG. 1 is disposed on the panel surface of the liquid crystal display panel, and the pattern phase difference film 1 corresponds to light emitted from pixels for the right eye and the left eye, respectively. To give the phase difference. Thereby, this image display apparatus displays a desired three-dimensional image by a passive method.

[Pattern retardation film]
In the pattern retardation film 1, for example, an alignment layer 3 and a retardation layer 4 are sequentially formed on a base 2 made of a transparent film material of triacetyl cellulose. In the pattern retardation film 1, the retardation layer 4 is formed of a liquid crystal material, and the alignment of the liquid crystal material is patterned by the alignment regulating force of the alignment layer 3. The orientation of the liquid crystal molecules is indicated by a long and narrow ellipse in FIG. By this patterning, the pattern phase difference film 1 is formed in a band shape alternately with the right-eye area A and the left-eye area B sequentially with a certain width corresponding to the pixel assignment in the liquid crystal display panel. A phase difference corresponding to each of the light emitted from the right-eye and left-eye pixels is given.

  In the pattern retardation film 1, after a photo-alignment material film made of a photo-alignment material is produced, the alignment layer 3 is formed by irradiating the photo-alignment material film with ultraviolet rays by linearly polarized light by a so-called photo-alignment technique. Here, the ultraviolet rays applied to the photo-alignment material film are set so that the direction of polarization differs between the right-eye region A and the left-eye region B by 90 degrees. The retardation layer 4 is produced by solidifying (curing) the liquid crystal material in an aligned state by the alignment regulating force of the alignment layer 3, whereby the pattern retardation film 1 includes the right eye region A and the left eye region. B gives a phase difference corresponding to the transmitted light.

〔Manufacturing process〕
FIG. 2 is a flowchart showing manufacturing steps of the pattern retardation film 1. In the manufacturing process of the pattern retardation film 1, the base material 2 is provided by a long transparent film material wound up on a roll, and the photo-alignment material film is sequentially produced while the base material 2 is fed from the roll and conveyed ( Step SP1-SP2). Here, although various manufacturing methods can be applied to the photo-alignment material film, in this embodiment, a film-forming liquid in which the photo-alignment material is dispersed in a solvent such as benzene is applied by a die and then dried. Is produced. As the photo-alignment material, various materials to which a photo-alignment technique can be applied can be applied.

  Subsequently, in the manufacturing process, the alignment layer 3 is produced by irradiating ultraviolet rays in the exposure process (step SP3). Subsequently, in this manufacturing process, in the retardation layer manufacturing process (step SP4), the coating liquid to be used for the preparation of the retardation layer is applied by a die or the like, and then dried and cured to prepare the retardation layer 4. . Subsequently, in this manufacturing process, after performing an antireflection film manufacturing process or the like as necessary, an adhesive layer and a separator film are arranged, and in the cutting process SP5, the pattern retardation film 1 is cut into a desired size. It is produced (steps SP6-SP7).

[Winding of pattern phase difference film material]
FIG. 3 is a diagram for explaining the retardation layer manufacturing step SP4. In the retardation layer preparation step SP4, the moisture-proof film is transferred from the roll 11 while conveying the base material 2 (hereinafter referred to as a pattern retardation film original fabric) in a long form formed by preparing the alignment layer 3 and the retardation layer 4. 12 is pulled out and laminated with the pattern retardation film original fabric 7 by the conveying rollers 13 and 14. In this embodiment, in a state where the moisture-proof film 12 and the pattern retardation film original fabric 7 are laminated in this manner, the pattern retardation film original fabric 7 is wound up to produce a wound body 15 of the pattern retardation film original fabric 7. To do. In addition, the pattern retardation film original fabric 7 may be provided with an antireflection film, an adhesive layer, a separator film, or the like as necessary. In this embodiment, the pattern retardation film 1 and the moisture-proof film 12 are alternately laminated in the radial direction by laminating with the moisture-proof film 12 and winding up the pattern retardation film original fabric 7 in this manner. The winding body 15 of the retardation film original fabric 7 is produced, and the deterioration of the dimensional accuracy of the pattern retardation film 1 due to moisture absorption of the substrate 2 is reduced.

  In the manufacturing process of the pattern phase difference film, the wound body 15 of the pattern phase difference film original fabric 7 thus produced is stored and transported and supplied to the cutting step. In the cutting step, the pattern phase difference film original fabric is supplied. The pattern retardation film original fabric 7 is pulled out from the wound body 15 of 7 and cut into a desired size.

  The pressure-sensitive adhesive layer and the separator film of the pattern retardation film 1 may be prepared before the pattern retardation film original film 7 is wound around the winding body 15, and the wound body 15 of the pattern retardation film original fabric 7. In some cases, the pattern retardation film original fabric 7 is pulled out to be separately prepared. When the separator film or the like is disposed before winding the pattern retardation film original fabric 7 in this way, naturally, the wound body 15 of the pattern retardation film original fabric 7 is adhered to the pattern retardation film original fabric 7. A layer and a separator film are provided. In the case where an adhesive layer and a separator film are separately provided and stored or transported for a certain period of time or more without being cut immediately, the adhesive layer and the separator film are newly provided after the adhesive layer and the separator film are provided. The wound body 15 of the pattern retardation film original fabric 7 is prepared and stored by laminating the patterned retardation film original fabric 7 and the moisture-proof film 12 formed.

  In addition, when an antireflection layer or the like is provided, it may be provided before the pattern retardation film original fabric 7 is wound on the winding body 15, and the pattern retardation film from the winding body 15 of the pattern retardation film original fabric 7. The original film 7 may be pulled out and provided separately. Even in such a case, the pattern retardation film original film 7 should be stored for a certain period of time as in the case of providing the adhesive layer and the separator film. When the film is transported or transported, the wound body 15 is prepared by storing the pattern retardation film original fabric 7 provided with an antireflection layer or the like and the moisture-proof film 12, and stored and transported.

Here, the moisture-proof film 12 is a film material that hardly permeates water vapor, and more specifically, is a film having a water vapor permeability of 0.1 g / m ² · day or less at 40 ° C. and 90%. The water vapor permeability is a value measured according to JIS7129. In this embodiment, although the moisture-proof film 12 is a PET film deposited with aluminum, various configurations can be applied as necessary.

  Further, the moisture-proof film 12 is set so as to be longer than the pattern retardation film original fabric 7, and in the wound body 15 of the pattern retardation film original fabric 7, the moisture-proof film is formed at the start and end of winding. It is set so that only 12 is wound. Thereby, in this embodiment, the pattern retardation film is prevented from being exposed on both the innermost periphery and the outermost periphery of the wound body 15, and the deterioration of the dimensional accuracy due to moisture absorption of the substrate is more reliably prevented.

  Further, as shown in FIG. 4, the moisture-proof film 12 is produced with a width W2 that is larger than the width W1 of the pattern retardation film original 7. 7 is disposed so that the moisture-proof film 12 protrudes from both ends. Thereby, in this embodiment, the moisture absorption of a pattern phase difference film is prevented further, and the fall of the dimensional accuracy of the pattern phase difference film by the moisture absorption of a base material is reduced.

  The wound body 15 of the pattern retardation film original fabric 7 is completely stored in a storage bag made of polypropylene film at the time of storage and transportation to prevent dust adhesion, scratches, etc., and this also prevents moisture absorption. A reduction in dimensional accuracy is prevented.

[Changes in dimensions]
5-7 is a figure which shows a measurement result about the dimensional change of the winding body which concerns on this embodiment, and the dimensional change in the winding body of a comparative example, when it is left to stand for a fixed time. FIG. 5 is a measurement result of Comparative Example 1 using a wound body of a pattern retardation film original film obtained by winding only the pattern retardation film original film, and FIG. 6 is Comparative Example 2 using the moisture-proof packaging described above with reference to FIG. This is the measurement result. FIG. 7 is a measurement result of an example which is the winding body 15 according to this embodiment.

  These measurements are made at each position from this end, based on the dimensions measured at a position 10 m from the winding end of the winding body (where the pattern retardation film original is pulled 10 m from the winding body). It is a figure which shows the change rate of the dimension measurement result. The dimensions were measured using a micro-dimension measuring device (Saturn 9100A manufactured by Buoy Technology Co., Ltd.) with a total pitch defined by the width of a predetermined number of strip-shaped regions corresponding to the upper and lower ends of the screen. Further, the winding bodies of the comparative example and the example have a diameter of 1 m at the outermost periphery. The measurement conditions were that the initial humidity was 40%, and the initial humidity was left as it was, and the humidity was changed to 50% and left as it was.

  According to FIGS. 5 to 7, it can be seen that when no moisture-proofing treatment is performed as in Comparative Example 1, the dimensions change greatly even after being left for about 10 minutes. However, although the conventional moisture-proof treatment as in Comparative Example 2 can reduce the dimensional change, it is still insufficient in practice, but in this embodiment, it can be seen that the dimensional change can be further reduced.

  FIG. 8 is a table summarizing the measurement results of FIGS. 8 that according to this embodiment, it is possible to sufficiently prevent a reduction in dimensional accuracy.

  According to another test, when the humidity is changed from the initial humidity of 40% to 60% and left for 24 hours, in Comparative Example 1, the dimensional change rate becomes 0.5% or more, but the configuration according to this embodiment Then, the dimensional change rate can be set to 0.2% or less, which can sufficiently prevent a decrease in dimensional accuracy due to moisture absorption of the base material.

[Cutting process]
In the cutting step SP5, the pattern retardation film original fabric 7 is pulled out from the wound body 15 of the pattern retardation film original fabric 7 in a state of being laminated with the moistureproof film 12, and is cut into a desired dimension and integrated with the moistureproof film 12. Laminate sequentially.

  Thereby, as shown in FIG. 9, cutting process SP5 produces the laminated body of the pattern phase difference film 1 so that the pattern phase difference film 1 and the moisture-proof film 12 may be laminated | stacked alternately one after another. In the manufacturing process, for every predetermined number of pattern retardation films 1, the alternating laminate of the pattern retardation film 1 and the moisture-proof film 12 is stored in a bag for storage and conveyance with a polypropylene film, and then packed and displayed. It is transported to the bonding process with the panel.

  Thus, by laminating | stacking the pattern phase difference film 1 and moisture-proof film 12 by a sheet | seat sequentially one after another, in this embodiment, even after cut | disconnecting to a pattern phase difference film, by the moisture absorption of the base material of a pattern phase difference film A decrease in dimensional accuracy can be sufficiently reduced.

  Note that only the pattern retardation film original fabric is drawn out from the wound body of the pattern retardation film original fabric only, or the pattern retardation film original fabric is wound by a laminate of the pattern retardation film original fabric and the moisture-proof film 12. Only the pattern retardation film is pulled out from the body, and immediately before cutting, the pattern retardation film original and the moisture-proof film are laminated and cut together, so that the pattern phase-difference film 1 and moisture-proof by sheet are laminated. You may make it laminate | stack the film 12 alternately.

[Second Embodiment]
FIG. 10 is a diagram for explaining the inspection process according to the second embodiment of the present invention. In the manufacturing process of this embodiment, the pattern retardation film original fabric 7 is cut out from the wound body 15A of the pattern retardation film original fabric 7 by a predetermined length to produce a test piece. Process control by measuring the pitch.

  In this embodiment, when producing a test piece by cutting from the pattern retardation film original fabric 7, a wound body 17 is produced by laminating with the moisture-proof film 12, and the test piece is formed according to the form of the wound body 17. It is transported to the inspection process and the test piece is measured. Here, in the wound body 17, the relationship between the moisture-proof film 12 and the pattern retardation film original fabric 7 is related to the length and width of the wound body 15 of the pattern retardation film original fabric 7 described above for the first embodiment. Is set the same as

  In addition, the winding body 15 by the laminated body of the pattern retardation film original fabric 7 and the moisture-proof film 12 is applied to the winding body which cuts out a test piece, and the pattern retardation film original fabric 7 and the moisture-proof film 12 are pulled out. By cutting integrally, a test piece is produced from a laminate of the patterned retardation film original and the moisture-proof film 12, and the test piece is wound up in the form of the laminate to produce a wound body 17. Also good.

  Thereby, in this embodiment, the fall of the dimensional accuracy by the moisture absorption of the base material in the cut test piece can be avoided effectively, and as a result, the dimensional measurement accuracy can be improved.

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

  That is, in the above-described embodiment, the case where the alignment layer is formed by applying the photo-alignment technique is described. However, the present invention is not limited to this, and when forming the alignment layer by rubbing, a fine line-shaped uneven shape is formed. The present invention can also be widely applied to the case where an alignment layer is produced by transferring the material by a forming process.

  Moreover, although the case where the PET film which vapor-deposited aluminum was applied to a moisture proof film was described in the above-mentioned embodiment, this invention is not restricted to this, Various moisture proof films can be applied widely.

  In the above-described embodiment, the case where the pattern retardation film is produced by processing the substrate with the long transparent film material has been described. However, the present invention is not limited thereto, and the pattern retardation is processed by processing the single wafer of the substrate. The present invention can be widely applied to the production of films.

  In the above-described embodiment, the case where the present invention is applied to the pattern retardation film used for the three-dimensional image display by the passive method has been described. However, the present invention is not limited thereto, and the first phase difference applied to the transmitted light is different. And it can apply widely to the optical film by which 2nd area | region is produced alternately one after another.

DESCRIPTION OF SYMBOLS 1 Pattern phase difference film 2 Base material 3 Orientation layer 4 Phase difference layer 7 Pattern phase difference film original fabric 11 Roll 12 Moisture-proof film 13, 14 Conveyance roller 15, 15A, 17 Winding body

Claims (5)

An alignment layer preparation step of preparing an alignment layer on a substrate made of a long transparent film material;
A retardation layer preparation step of preparing a retardation layer on the alignment layer to prepare an optical film original fabric,
A method for producing an optical film, wherein a moisture-proof film and the optical film original fabric are laminated and wound on a roll to produce a wound body of the optical film original fabric. An alignment layer preparation step of preparing an alignment layer on a substrate made of a transparent film material;
A retardation layer production step of producing an optical film by producing a retardation layer on the alignment layer,
A method for producing an optical film, in which a moisture-proof film and the optical film are alternately and sequentially laminated to produce a laminate of optical films. From the roll of the optical film original in the form of a long transparent film material, the optical film original is pulled out and cut, and a test piece of the optical film original is produced.
Winding the laminate of the test piece and moisture-proof film to produce a wound body of the optical film original fabric according to the test piece,
A method for measuring an optical film, comprising: measuring a dimension of the original optical film from a wound body of the original optical film according to the test piece. A wound body of an optical film original, which is wound in a state where a moisture-proof film is laminated on an optical film original having an orientation layer and a retardation layer on a substrate made of a long transparent film material. A laminate of optical films formed by sequentially laminating optical films made of a single wafer provided with an orientation layer and a retardation layer on a substrate made of a transparent film material, and moisture-proof films.

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