JP2017068196A - Light control film and manufacturing method of light control film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light control film that can be reliably manufactured by laminating transparent film materials without hindering alignment of liquid crystal.SOLUTION: First and second transparent film materials 6 and 15 formed by providing at least alignment layers 13 and 17 are laminated while sandwiching a liquid crystal layer 8, and is applied to a light control film 1 that controls alignment of liquid crystal in the liquid crystal layer 8 through the drive of transparent electrodes 11 and 16 provided on the first film material 6 or second film material 15 to control transmitted light. The light control film 1 includes a frame-shape isolation wall 21 surrounding the liquid crystal layer 8, and the first and second film materials 6 and 15 are made as one body with a frame-shape sealing material 20 surrounding the isolation wall 21.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light control film that can be used for, for example, an electronic blind that is attached to a window to control the transmission of extraneous light.

  Conventionally, for example, various devices relating to a light control film that is attached to a window to control the transmission of external light have been proposed (Patent Documents 1 and 2). One such light control film uses liquid crystal. The light control film using the liquid crystal is produced by sandwiching a liquid crystal material with a transparent film material on which a transparent electrode is produced, and producing the liquid crystal cell with a linear polarizing plate. As a result, in this light control film, the orientation of the liquid crystal is changed by changing the electric field applied to the liquid crystal, thereby blocking or transmitting the extraneous light, and further changing the amount of transmitted light. To control.

  In addition, a liquid crystal display panel, which is one of the image display panels, includes a liquid crystal cell sandwiched between a pair of glass plates made of transparent electrodes and alignment layers, and the liquid crystal cell is sandwiched between linear polarizing plates. Configured. The liquid crystal display panel displays a desired image by changing the electric field applied to the liquid crystal in units of pixels by patterning the transparent electrode.

  Further, in the image display panel, a sealing material made of a thermosetting resin is arranged in a frame shape surrounding the liquid crystal layer, and the leakage of the liquid crystal material is prevented by this sealing material, and further, a pair of glass substrates sandwiching the liquid crystal layer is provided. Bonded together and held together.

  By the way, even if it exists in a light control film, it is thought that it can produce by the process similar to a liquid crystal display panel. As a result, even in the light control film, a sealing material made of a thermosetting resin is disposed in a transparent film material formed by manufacturing a transparent electrode or the like in a frame shape, and a liquid crystal material is placed in a region surrounded by the frame shape. It is considered that a liquid crystal cell can be manufactured by arranging and then laminating and integrating the sealing material with the corresponding transparent film material.

  However, the light control film is manufactured by using a transparent film material to produce a liquid crystal cell. By simply heating the sealing material and integrating it with the corresponding transparent film material, There is a problem that it is difficult to securely bond the transparent film material.

  As one method for solving this problem, a transparent film material is laminated at room temperature, and then heated in this laminated state to cure the sealing material, thereby laminating and integrating the transparent film material to produce a liquid crystal cell. Can be considered. However, if this is done, the uncured sealing material will come into contact with the liquid crystal material, and the alignment of the liquid crystal will be locally obstructed, resulting in uneven brightness, and incomplete bonding with the sealing material. There is a problem that becomes.

JP 03-47392 A Japanese Patent Laid-Open No. 08-184273

  The present invention has been made in view of such a situation, and an object of the present invention is to make it possible to reliably produce a transparent film material on a light control film without impeding liquid crystal alignment. And

  The inventor has conducted extensive research to solve the above problems, and after laminating the transparent film material, it is integrated by heating to cure the sealing material, and an isolation wall with a frame shape is provided, The idea of preventing the uncured sealing material from coming into contact with the liquid crystal material by the separating wall has led to the completion of the present invention.

  Specifically, the present invention provides the following.

(1) First and second transparent film materials each including at least an alignment layer are stacked with a liquid crystal layer interposed therebetween, and driving of the transparent electrode provided on the first and / or second transparent film material is performed. In the light control film for controlling the transmitted light by controlling the orientation of the liquid crystal according to the liquid crystal layer,
An isolation wall having a frame shape surrounding the liquid crystal layer;
The light control film in which the said 1st and 2nd transparent film material was integrated by the sealing material by the frame shape surrounding the said isolation wall.

  According to (1), the uncured sealing material and the liquid crystal material can be prevented from coming into contact with each other by the separating wall, and as a result, the alignment of liquid crystal generated by the contact between the uncured sealing material and the liquid crystal material is inhibited. Can be effectively avoided, and defective bonding of the transparent film material can be effectively avoided.

(2) In (1),
The first and / or second transparent film material is provided with a spacer for maintaining the thickness of the liquid crystal layer,
The isolation wall is a light control film provided with the same material and height as the spacer.

  According to (2), an isolation wall can be produced together in the spacer production process.

(3) In (1) or (2),
The light control film which equips the opposite side surface with the said liquid crystal layer of the said 1st and 2nd transparent film material and has the optically functional layer of a linearly-polarizing plate.

  According to (3), it is applied to a configuration for dimming by controlling the polarization plane of transmitted light that passes through the liquid crystal layer, and is produced by securely bonding a transparent film material without impeding liquid crystal alignment. can do.

(4) In (1) or (2),
The light control film whose said liquid crystal layer is a liquid crystal layer by a guest host liquid crystal.

  According to (4), it can be applied to the configuration in which the light is adjusted by the guest-host liquid crystal and can be produced by reliably bonding the transparent film material without inhibiting the alignment of the liquid crystal.

(5) First and second transparent film materials each having at least an alignment layer are laminated with a liquid crystal layer interposed therebetween, and by driving a transparent electrode provided on the first and / or second transparent film material. In the method of manufacturing a light control film for controlling the transmitted light by controlling the alignment of the liquid crystal according to the liquid crystal layer,
An isolation wall production step of producing an isolation wall in a frame shape on the first or second transparent film material;
A sealing material arrangement step of arranging a sealing material in a shape surrounding the isolation wall;
A liquid crystal material disposing step of disposing a liquid crystal material according to the liquid crystal layer in a portion surrounded by the isolation wall;
A laminating step of laminating the first and second transparent film materials at room temperature with the liquid crystal material interposed therebetween;
A heating integration step of curing the sealing material by heating in a state where the first and second transparent film materials are laminated, and integrating the first and second transparent film materials by the sealing material. Manufacturing method of light control film.

  According to (5), after laminating the uncured sealing material and the liquid crystal material so as not to contact with each other by the separating wall, the sealing material can be cured, whereby the uncured sealing material and the liquid crystal material can be cured. It is possible to effectively avoid the obstruction of the alignment of the liquid crystal generated by the contact, and to effectively avoid the defective bonding of the transparent film material.

(6) In (5),
The isolation wall manufacturing process includes:
A method for producing a light control film, wherein the isolation wall is produced together with a spacer for defining a thickness of the liquid crystal layer by exposing and developing a photoresist film.

  According to (6), an isolation wall can be produced together in the spacer production process.

  According to the present invention, the light control film can be produced by reliably bonding the transparent film material without inhibiting the orientation of the liquid crystal.

It is a figure which shows the light control film which concerns on 1st Embodiment of this invention. It is AA sectional drawing of the light control film of FIG. It is a flowchart which shows the manufacturing process of the light control film of FIG. It is a figure where it uses for description of the manufacturing process of FIG. It is a figure which shows the light control film which concerns on 2nd Embodiment of this invention. It is a figure which shows the light control film which concerns on 3rd Embodiment of this invention.

[First Embodiment]
[Light control film]
FIG. 1 is a cross-sectional view showing a light control film according to the first embodiment of the present invention. This light control film 1 is used by being attached to an area for light control such as a window glass of a building, a showcase, an indoor transparent partition, etc. with an adhesive layer or the like, and the amount of transmitted light can be reduced by changing the applied voltage. Control.

  This light control film 1 is a film material that controls transmitted light using liquid crystal, and is configured by sandwiching a liquid crystal cell 4 for light control film between linear polarizing plates 2 and 3. Here, the linear polarizing plates 2 and 3 are formed by impregnating polyvinyl alcohol (PVA) with iodine or the like, and then stretched to form an optical functional layer that performs an optical function as a linear polarizing plate. TAC (triacetyl cellulose) The optical functional layer is sandwiched between base materials made of a transparent film material such as the above. The linearly polarizing plates 2 and 3 are arranged in the liquid crystal cell 4 by adhesive layers 2A and 3A made of an ultraviolet curable resin or the like in a crossed Nicol arrangement.

  The liquid crystal cell 4 controls the polarization plane of transmitted light by an applied voltage to a transparent electrode described later. Thereby, the light control film 1 is comprised so that transmitted light can be controlled and various light control can be aimed at.

  The liquid crystal cell 4 is configured by sandwiching a liquid crystal layer 8 between an upper laminate 5U and a lower laminate 5D which are first and second laminates in a film shape. The lower laminate 5D is formed by laminating a transparent electrode 11, a spacer 12, and an alignment layer 13 on a substrate 6 made of a transparent film material. The upper laminate 5U is formed by laminating a transparent electrode 16 and an alignment layer 17 on a base material 15 made of a transparent film material. Here, as the base materials 6 and 15, various transparent film materials applicable to this kind of film material can be applied. For example, optical anisotropy such as a polycarbonate film, a COP (cycloolefin polymer) film, a TAC film, etc. It is desirable to apply a small film material.

  The liquid crystal cell 4 in FIG. 1 may be driven by, for example, an IPS (In-plane Switching) method, although the alignment of the liquid crystal is controlled by a pair of counter electrodes that sandwich the liquid crystal material. In this case, either the transparent electrode 11 or 16 of the upper laminate 5U or the lower laminate 5D is omitted, and an electric field for driving is applied to the liquid crystal material by patterning the other transparent electrode. The spacer 12 may be provided in the upper laminate 5U, or may be provided in both the upper laminate 5U and the lower laminate 5D.

  Here, the transparent electrodes 11 and 16 can employ various electrode materials applied to this type of film material. In this embodiment, the transparent electrodes 11 and 16 are formed of a transparent electrode material made of ITO (Indium Tin Oxide). The spacer 12 is provided to define the thickness of the liquid crystal layer 8, and various resin materials can be widely applied. It is produced by applying a photoresist on 6 and exposing and developing. Here, a known photosensitive resist material can be applied to the photoresist, and more specifically, an acrylic ester-based photosensitive resist material, a cinnamic ester-based photosensitive resist material system, and a rubber-based photoresist. A photosensitive resist material or the like can be applied.

  The alignment layers 13 and 17 are produced by rubbing a polyimide resin layer. The alignment layers 13 and 17 can be applied with various configurations capable of expressing the alignment regulating force with respect to the liquid crystal material related to the liquid crystal layer 8, and may be formed by a so-called photo-alignment layer. You may form and form the fine line-shaped uneven | corrugated shape by a process by a shaping process. The spacer 12 may be formed on the alignment layer 13.

  In addition, although various materials to which the photo-alignment technique can be applied can be applied as the photo-alignment material, in this embodiment, the alignment is not changed by ultraviolet irradiation after the alignment, for example, a light dimerization type. Use materials. 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, H. Seiberle and A. Schuster: Nature, 381, 212 (1996).

  Various liquid crystal materials applicable to this type of light control film can be widely applied to the liquid crystal layer 8.

[Lamination of upper laminate and lower laminate]
As shown in FIG. 2 by taking a cross section along the line AA, the liquid crystal cell 4 has a sealing material 20 arranged in a frame shape surrounding the liquid crystal layer 8, and the sealing material 20 allows the upper laminated body 5U and the lower laminated body. The 5D is bonded and held together, and the liquid crystal material related to the liquid crystal layer 8 is prevented from leaking. Here, a thermosetting resin is applied to the sealing material 20, whereby the liquid crystal cell 4 cures the sealing material 20 by heating and the upper stacked body 5 </ b> U and the lower stacked body 5 </ b> D are bonded together.

  In the liquid crystal cell 4, an isolation wall 21 is provided inside the sealing material 20 by a frame shape. Here, the isolation wall 21 is configured to isolate the liquid crystal material related to the liquid crystal layer 8 from the uncured sealing material 20 so that the liquid crystal material related to the liquid crystal layer 8 and the uncured sealing material 20 do not contact each other. is there. By providing the isolation wall 21 in this manner, in this embodiment, the upper laminate 5U and the lower laminate 5D made of a transparent film material formed with an alignment layer and the like are laminated, and then heated to be sealed 20 Even if it hardens | cures and integrates, it is comprised so that the uncured sealing material 20 may not contact the liquid-crystal material which concerns on the liquid-crystal layer 8. FIG. Thereby, the light control film 1 can be produced by securely bonding the base materials 6 and 15 without inhibiting the alignment of the liquid crystal.

  The isolation wall 21 is manufactured together with the spacer 1 by the setting of a mask used for exposure when the spacer 12 is manufactured, and is thus manufactured with the same material and height as the spacer 12. Thereby, the light control film 1 is comprised so that the uncured sealing material 20 may not contact the liquid crystal material which concerns on the liquid crystal layer 8 reliably by a simple process. In addition, by manufacturing the isolation wall 21 by setting the mask used for exposure when manufacturing the spacer 12 in this way, the isolation wall 21 is manufactured with a remarkably higher dimensional accuracy than the sealing material 20. can do. Thereby, with respect to the liquid crystal layer 8, liquid crystal can be arranged with an appropriate liquid amount with high accuracy, and management of the liquid crystal material can be simplified. In addition, since the liquid volume of the liquid crystal can be accurately controlled in this way, it is possible to surely prevent a situation in which the liquid crystal dripped excessively and the liquid crystal gets over the isolation wall 21, thereby also adjusting the alignment of the liquid crystal. The light control film 1 can be produced by securely bonding the transparent film material without hindering.

〔Manufacturing process〕
FIG. 3 is a flowchart for explaining the manufacturing process of the light control film. In the manufacturing process, the transparent electrodes 11 and 16 are respectively formed on the substrates 6 and 15 by applying a photolithography technique in the transparent electrode manufacturing process SP1. In the subsequent spacer / separation wall manufacturing step SP3, a photoresist film is formed on the substrate 6 formed by manufacturing the transparent electrode 11 related to the lower laminate 5D, and then exposed and developed, whereby the spacer 12 The isolation wall 21 is produced.

  In this manufacturing process, in the subsequent alignment layer preparation process SP4, after applying a polyimide resin layer coating solution, drying and heat treatment are performed, thereby preparing a polyimide film. In addition, the polyimide film is rubbed to produce the alignment layers 13 and 17. Thus, in this manufacturing process, the upper laminate 5U and the lower laminate 5D are produced. The spacer 12 and the isolation wall 21 may be formed on the alignment layer by providing the manufacturing process after the alignment layer creating process.

  Further, in this manufacturing process, as shown in FIG. 4, in the sealing material arrangement process SP5, the sealing material 20 is applied to the lower laminate 5D in a frame shape by a dispenser and dried. In this manufacturing process, a liquid crystal material is dropped onto a portion surrounded by the sealing material 20. The dropping of the liquid crystal material and the arrangement of the sealing material 20 may be switched in order. Here, it is desirable that the sealing material 20 is configured so that no gap is generated between the lower laminate 5D and the isolation wall 21 when the upper laminate 5U is laminated on the lower laminate 5D and then pressed and bonded. At the time of coating, it may be arranged so as to partially contact the isolation wall 21 or be very close to the isolation wall 21. In addition, although the sealing material 20 is crushed by laminating and pressing the upper laminated body 5U on the lower laminated body 5D, in such a case where the sealing material 21 is partially in contact with the separating wall 21, The seal material 20 to be crushed will be spread outward. Thus, even when the sealing material 20 is partially in contact with the isolation wall 21 as described above, the uncured sealing material and the liquid crystal material can be prevented from contacting each other.

  More specifically, the sealing material 20 is produced with a coating width of 100 μm or more and 1000 μm or less, preferably with a coating width of 300 μm or more and 700 μm or less. The gap between the sealing material 20 and the isolation wall 21 is set to an interval of 0 μm to 1000 μm, preferably an interval of 0 μm to 300 μm. The isolation wall 21 is manufactured with a width of 0.5 mm or more and 3 mm or less, preferably 0.8 mm or more and 1.2 mm or less. The sealing material 21 is applied with a dry film thickness of 20 μm or more and 100 μm or less, while the spacer 12 is produced from the surface of the alignment layer 13 with a height of 3 μm or more and 15 μm or less.

  In this manufacturing process, in the subsequent stacking step SP6, the upper stacked body 5U is brought and stacked with the lower stacked body 5D. In this manufacturing process, the upper laminate 5U is laminated at the atmospheric pressure by exhausting the air in the space formed between the upper laminate 5U and the lower laminate 5D. Press to 5D. Further, the upper laminated body 5U and the lower laminated body 5D are integrally heated while being pressed by the atmospheric pressure in this way, whereby the sealing material 20 is cured and bonded and integrated. In addition, you may press with members, such as a board | plate material, instead of the press by such atmospheric pressure. In this embodiment, since the isolation wall 21 is provided, even when the sealing material 20 is cured by heating after being laminated and pressed at room temperature, the uncured sealing material 20 and the liquid crystal material Can be kept out of contact. Thereby, the light control film 1 can be produced by securely bonding the transparent film material without inhibiting the alignment of the liquid crystal.

  In addition, since the separation wall 21 can be manufactured with high accuracy, in the dropping step related to the liquid crystal material, the management can be simplified, and the liquid crystal can be dropped with an appropriate amount of liquid with high accuracy. Management can be simplified. In addition, since the liquid volume of the liquid crystal can be accurately controlled in this way, it is possible to surely prevent a situation in which the liquid crystal dripped excessively and the liquid crystal gets over the isolation wall 21, thereby also adjusting the alignment of the liquid crystal. The light control film 1 can be produced by securely bonding the transparent film material without hindering.

  In this manufacturing process, in the subsequent linear polarizing plate laminating step SP8, the linear polarizing plates 2 and 3 are arranged by an adhesive layer such as an ultraviolet curable resin layer (FIG. 1).

[Second Embodiment]
FIG. 5 is a cross-sectional view showing a light control film according to a second embodiment of the present invention in comparison with FIG. In this light control film 41, instead of the spacer 12, a so-called bead spacer made of a sphere is arranged, and the thickness of the liquid crystal layer 8 is defined by this bead spacer. In FIG. 5, the description of the bead spacer is omitted. In addition, in the structure of this FIG. 5, the code | symbol corresponding to the structure same as the light control film 1 mentioned above is attached | subjected, and the overlapping description is abbreviate | omitted. Thereby, in this embodiment, after producing a transparent electrode or producing an alignment layer, only the isolation wall 21 is produced.

  Even when a bead spacer is applied as in this embodiment, the same effects as in the first embodiment can be obtained.

[Third Embodiment]
FIG. 6 is a cross-sectional view showing a light control film according to a third embodiment of the present invention. The light control film 51 is formed by sandwiching a liquid crystal layer 60 of guest-host type liquid crystal between the upper laminate 5U and the lower laminate 5D. In addition, in the structure of this FIG. 6, the code | symbol corresponding to the same structure as the light control film 1 mentioned above is attached | subjected, and the overlapping description is abbreviate | omitted.

  Even when the guest-host type liquid crystal is used and the linear polarizing plate is omitted, the same effects as those of the above-described embodiment can be obtained.

[Other Embodiments]
The specific configuration suitable for the implementation of the present invention has been described in detail above, but the present invention can be variously combined and modified in various ways within the scope of the present invention.

  That is, in the first embodiment described above, the case where the isolation wall is manufactured simultaneously with the spacer has been described. However, the present invention is not limited to this, and an isolation wall manufacturing process may be separately provided to manufacture the isolation wall. .

DESCRIPTION OF SYMBOLS 1, 41, 51 Light control film 2, 3 Linear polarizing plate 2A, 3A Adhesive layer 4 Liquid crystal cell 5D Lower laminated body 5U Upper laminated body 6, 15 Base material 8, 60 Liquid crystal layer 11, 16 Transparent electrode 12 Spacer 13 , 17 Orientation layer 20 Sealing material 21 Isolation wall

Claims (6)

First and second transparent film materials each having at least an alignment layer are laminated with a liquid crystal layer interposed therebetween, and the liquid crystal layer is driven by driving a transparent electrode provided on the first and / or second transparent film material. In the light control film that controls the transmitted light by controlling the orientation of the liquid crystal according to
An isolation wall having a frame shape surrounding the liquid crystal layer;
The light control film which the said 1st and 2nd transparent film material was integrated by the sealing material by the frame shape surrounding the said isolation wall. The first and / or second transparent film material is provided with a spacer for maintaining the thickness of the liquid crystal layer,
The light control film according to claim 1, wherein the isolation wall is provided with the same material and height as the spacer. The light control film according to claim 1, further comprising an optical functional layer of a linearly polarizing plate on a side surface opposite to the liquid crystal layer of the first and second transparent film materials. The light control film according to claim 1, wherein the liquid crystal layer is a liquid crystal layer made of guest-host liquid crystal. First and second transparent film materials each having at least an alignment layer are laminated with a liquid crystal layer interposed therebetween, and the liquid crystal layer is driven by driving a transparent electrode provided on the first and / or second transparent film material. In the manufacturing method of the light control film which controls the transmitted light by controlling the orientation of the liquid crystal according to
An isolation wall production step of producing an isolation wall in a frame shape on the first or second transparent film material;
A sealing material arrangement step of arranging a sealing material in a shape surrounding the isolation wall;
A liquid crystal material disposing step of disposing a liquid crystal material according to the liquid crystal layer in a portion surrounded by the isolation wall;
A laminating step of laminating the first and second transparent film materials at room temperature with the liquid crystal material interposed therebetween;
A heating integration step of curing the sealing material by heating in a state where the first and second transparent film materials are laminated, and integrating the first and second transparent film materials by the sealing material. Manufacturing method of light control film. The isolation wall manufacturing process includes:
The method for producing a light control film according to claim 5, wherein the isolation wall is produced together with a spacer for defining a thickness of the liquid crystal layer by exposing and developing a photoresist film.

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