JP2018112629A - Light control cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress in-plane variation of applied voltage to effectively make in-plane variation of transmissivity less conspicuous.SOLUTION: A light control cell 20 is capable of changing transmissivity. The light control cell includes a first substrate 30, a second substrate 40, a liquid crystal layer 55 arranged between the first substrate and the second substrate, and a sealant 51 arranged between the first substrate and the second substrate and surrounding the liquid crystal layer in a circular pattern. At least one substrate of the first substrate and the second substrate includes electrodes 33, 43. Circumference edges 39, 49 of the at least one substrate are positioned outside the sealant in an area larger than half of the circumference.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light control cell capable of changing transmittance using a liquid crystal layer.

  Patent Document 1 discloses a light control glass window (light control cell) in which the light transmittance can be adjusted in various patterns according to changes in sunshine conditions. According to this light control glass window, the transmittance can be adjusted by changing the voltage acting on the liquid crystal molecules in the liquid crystal layer enclosed between the two transparent glass substrates to change the orientation of the liquid crystal molecules. Can do.

Japanese Patent Laid-Open No. 08-184273

  By the way, when the region for adjusting the transmittance of the light control cell becomes wide, in-plane variation of the voltage occurs in this region when the voltage is applied to the electrode. At this time, the orientation of liquid crystal molecules driven by voltage application is non-uniform in the plane, and as a result, the transmittance varies in the plane. In particular, when the liquid crystal molecules are driven with an alternating voltage, it may even occur that the orientation of the liquid crystal molecules is not switched at a position away from the voltage source.

  The present invention has been made in consideration of such points, and an object thereof is to reduce the in-plane variation in transmittance due to the in-plane variation in applied voltage.

The dimming cell according to the present invention comprises:
A dimming cell with variable transmittance,
A first substrate including a first resin substrate;
A second substrate including a second resin base material;
A liquid crystal layer provided between the first substrate and the second substrate;
A sealant positioned between the first substrate and the second substrate and surrounding the liquid crystal layer in a circumferential shape,
At least one of the first substrate and the second substrate includes an electrode;
The peripheral edge of the at least one substrate is an area that is not less than a half circumference of the sealing material, and is located outward from the sealing material.

In the light control cell according to the present invention, the peripheral edge of the at least one substrate may be located outside the sealing material in a region where the sealing material 51 is a continuous half or more.

  In the light control cell according to the present invention, the peripheral edge of the at least one substrate may be located outward from the sealing material over the entire periphery.

  In the light control cell according to the present invention, the sheet resistance of the electrode may be not less than 100Ω / □ and not more than 1000Ω / □.

  In the light control cell according to the present invention, a maximum distance between any two points in a region of the electrode facing the liquid crystal layer may be 20 cm or more and 150 cm or less.

In the dimming cell according to the present invention,
The electrode includes a connection region with an external power source,
Regarding the length along the current path from the connection region to an arbitrary position in the region of the electrode facing the liquid crystal layer, the difference between the longest length and the shortest length is 20 cm or more. It may be 150 cm or less.

  According to the present invention, in-plane variation in applied voltage can be suppressed, and in-plane variation in transmittance can be effectively made inconspicuous.

FIG. 1 is a view for explaining an embodiment of the present invention, and is a longitudinal sectional view showing a schematic configuration of a light control device. FIG. 2 is a longitudinal sectional view showing an example of a light control cell included in the light control apparatus of FIG. FIG. 3 is a longitudinal sectional view corresponding to FIG. 2 and showing another example of the light control cell. FIG. 4 is a diagram for explaining a method of manufacturing the light control cell. FIG. 5 is a diagram for explaining a method of manufacturing the light control cell. FIG. 6 is a diagram for explaining a method of manufacturing the light control cell. FIG. 7 is a plan view showing the light control cell. 8 is a cross-sectional view taken along line XIII-XIII in FIG. FIG. 9 is a diagram corresponding to FIG. 7 and illustrating a modified example of the light control cell. 10 is a cross-sectional view taken along line XX in FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product. Further, in this specification, the terms “plate”, “sheet” and “film” are not distinguished from each other only based on the difference in designation. For example, the term “plate” is a concept including a member that can be called a sheet or a film. In addition, the terms used in this specification, the geometric conditions, and the terms that specify the degree thereof (for example, terms such as “parallel”, “orthogonal” and “same”, length and angle values, etc.) are strictly Without being bound by any meaning, it is interpreted as meaning a range where substantially equivalent and similar functions can be expected.

  1 to 10 are diagrams for explaining an embodiment of the present invention. Among these, FIG. 1 is a diagram schematically showing the light control device. 2 and 3 are longitudinal sectional views showing a schematic configuration of the light control cell. 4-6 is a figure for demonstrating an example of the manufacturing method of a light control cell.

  As shown in FIG. 1, the dimming device 10 includes a dimming cell 20 and a dimming controller 12 electrically connected to the dimming cell 20. The light control cell 20 includes a first substrate 30 and a second substrate 40, a plurality of spacers 50 provided between the first resin base material 32 and the second resin base material 42, the first substrate 30 and the first substrate 30. A liquid crystal layer 55 provided between the two substrates 40 and a sealing material 51 that surrounds the liquid crystal layer 55 in a circumferential shape between the first substrate 30 and the second substrate 40 are provided. In the illustrated example, the first substrate 30 includes a first resin base material 32, and the second substrate 40 includes a second resin base material 42. Further, at least one of the first substrate 30 and the second substrate 40 includes an electrode 33. In the light control device 10, the transmittance of light transmitted through the light control cell 20 can be changed according to the degree of voltage application from the light control controller 12 to the electrode 33.

  The application object of the light control apparatus 10 is not specifically limited, Typically, the light control cell 20 can be applied to a window, a door, or the like. In particular, by fixing the relative positions of the first substrate 30 and the second substrate 40 using the spacer 50, the dimming cell 20 can be installed in an environment where an external force such as vibration is applied. Therefore, the dimming cell 20 can be applied not only to windows and doors of buildings, but also to windows and doors of vehicles such as airplanes, ships, trains, and automobiles. In application to such windows and doors, the light control cell is used by being bonded to a transparent member such as glass or sandwiched between a pair of transparent members such as glass.

  Hereinafter, each component of the light control apparatus 10 is demonstrated. First, components other than the dimming cell 20 will be described.

  In the example shown in FIG. 1, a sensor device 14 and a user operation unit 16 are connected to the dimming controller 12. The dimming controller 12 controls the dimming state of the dimming cell 20, switches between blocking and transmitting light by the dimming cell 20, and changes the transmittance (transmittance) of the light that passes through the dimming cell 20. Can be. Specifically, the dimming controller 12 adjusts the voltage applied to the liquid crystal layer 55 of the dimming cell 20 to change the orientation of the liquid crystal molecules in the liquid crystal layer 55, thereby blocking light by the dimming cell 20. The transmission can be switched and the light transmission can be changed.

  The dimming controller 12 can adjust the voltage applied to the liquid crystal layer 55 based on an arbitrary method. For example, the dimming controller 12 adjusts the voltage applied to the liquid crystal layer 55 in accordance with the measurement result of the sensor device 14 or an instruction (command) input by the user via the user operation unit 16, and the dimming cell 20. It is possible to switch between blocking and transmitting light and changing the light transmittance. Therefore, the dimming controller 12 may automatically adjust the voltage applied to the liquid crystal layer 55 according to the measurement result of the sensor device 14 or manually according to a user instruction via the user operation unit 16. May be adjusted. Note that the measurement target by the sensor device 14 is not particularly limited. For example, the brightness of the usage environment may be measured. In this case, the light control cell 20 may block light and switch transmission or change the light transmittance. This is done according to the brightness of the usage environment. In addition, both the sensor device 14 and the user operation unit 16 are not necessarily connected to the dimming controller 12, and only one of the sensor device 14 and the user operation unit 16 may be connected. .

  Next, the light control cell 20 will be described. As described above, the light control cell 20 includes the pair of substrates 30 and 40 and the liquid crystal layer 55 disposed between the pair of substrates 30 and 40. At least one of the pair of substrates 30 and 40 has an electrode. The first substrate 30 and the second substrate 40 have a configuration that makes it possible to change the orientation of the liquid crystal molecules contained in the liquid crystal material 56 forming the liquid crystal layer 55 by applying a voltage from the dimming controller 12. Yes. The driving method of the liquid crystal molecules is not particularly limited, and for example, a VA (Vertical Alignment) method, a TN (Twisted Nematic) method, an IPS (In Plane Switching) method, a GH (Guest Host) method, or these methods. Applied methods can be adopted.

  The first substrate 30, the second substrate 40, and the liquid crystal layer 55 can be appropriately selected according to the adopted liquid crystal molecule driving method. For example, when the IPS method is adopted, only one of the first substrate 30 and the second substrate 40 may have an electrode. When the GH method is adopted, the liquid crystal material 56 forming the liquid crystal layer 55 includes a dichroic dye together with liquid crystal molecules. Furthermore, when the GH method is employed, one or both of the first substrate 30 and the second substrate 40 may not include a polarizing plate.

  Here, FIG. 2 shows a specific configuration example of the dimming cell 20 adopting the VA method. Hereinafter, a specific example of the light control cell 20 will be described with reference to the example shown in FIG.

  In the example shown in FIG. 2, the first substrate 30 includes a first polarizing plate 31, a first resin base material 32, a first electrode 33, and a first alignment film 34 in order from the side away from the liquid crystal layer 55. Have. Similarly, the second substrate 40 includes a second polarizing plate 41, a second resin base material 42, a second electrode 43, and a second alignment film 44 in order from the side away from the liquid crystal layer 55.

  Among these, the 1st polarizing plate 31 and the 2nd polarizing plate 41 are demonstrated first. The polarizing plates 31 and 41 selectively absorb one linearly polarized light component that vibrates in a direction parallel to the absorption axis and select the other linearly polarized light component that vibrates in a direction parallel to the transmission axis perpendicular to the absorption axis. It is a layer having a polarizing function for transmitting light. As a specific configuration, the polarizing plates 31 and 41 may include a polarizer and an adhesive layer for bonding the polarizer to the resin base materials 32 and 42. The polarizer is configured to exhibit a desired polarization function, and is typically made by stretching PVA (polyvinyl alcohol) doped with an iodine compound. Generally, when a polarizer is made by stretching, the absorption axis of the polarizer is determined according to the direction of the stretching, and the polarizers stretched in the same direction have absorption axes in the same direction. As an arrangement mode of the first polarizing plate 31 and the second polarizing plate 41, a mode called “parallel Nicol” in which the absorption axis of the first polarizing plate 31 and the absorption axis of the second polarizing plate 41 are parallel to each other, There is an aspect called “cross Nicol” in which the absorption axis of the polarizing plate 31 and the absorption axis of the second polarizing plate 41 are perpendicular to each other. In the VA system, the transmittance in the non-transmissive state can be more reliably lowered by disposing the first polarizing plate 31 and the second polarizing plate 41 in “crossed Nicols”.

  Next, the first resin substrate 32 and the second resin substrate 42 will be described. The resin base materials 32 and 42 are made of sheet-like resin. By using the resin base materials 32 and 42 instead of the glass base material, a thin and light weight can be realized. Moreover, by using the resin base materials 32 and 42, flexibility can be imparted to the light control cell 20, and the light control cell 20 can be formed into a three-dimensional curved surface shape as well as a two-dimensional curved surface shape. Here, the two-dimensional curved surface is a curved surface that is bent two-dimensionally around a single axis, or a curved surface that is bent two-dimensionally with the same or different curvature around a plurality of parallel axes. is there. On the other hand, the three-dimensional curved surface means a surface that is partially or wholly bent around each of a plurality of non-parallel axes.

  As a specific example, the resin base materials 32 and 42 may include a plurality of resin layers. For example, the resin base materials 32 and 42 may have a pair of hard coat layers and a main resin layer disposed between the pair of hard coat layers. Each hard coat layer serves to protect the adjacent main resin layer and can be made of any material that can transmit visible light. The hard coat layer may be made of, for example, TAC (Triacetylcellulose) or acrylic, and may be attached to the main resin layer via an adhesive layer. Further, a cured film containing fine particles (for example, titanium dioxide) may be formed on the surface of the main resin layer using, for example, a silicone-based ultraviolet curable resin, and the cured film may function as a hard coat layer. The hard coat layers formed at a plurality of locations of the first resin base material 32 and the second resin base material 42 may be made of different materials depending on the arrangement position, or may be made of the same material. Good.

  Next, the first electrode 33 and the second electrode 43 will be described. The electrodes 33 and 43 are formed as transparent electrodes from various materials such as ITO (Indium Tin Oxide). The electrodes 33 and 43 are connected to the dimming controller 12 through, for example, an FPC. The arrangement | positioning aspect of the 1st electrode 33 and the 2nd electrode 43 is not specifically limited, An electrode may be arrange | positioned only by the predetermined location by patterning formation, and an electrode may be arrange | positioned at solid form. An electric field acting on the liquid crystal layer 55 disposed between the first electrode 33 and the second electrode 43 is formed according to the voltage applied to the first electrode 33 and the second electrode 43, and the liquid crystal layer 55 is configured. The alignment of the liquid crystal molecules in the liquid crystal material 56 is adjusted.

  Next, the first alignment film 34 and the second alignment film 44 will be described. The alignment films 34 and 44 are layers adjacent to the liquid crystal layer 55 and control the alignment of the liquid crystal molecules in the liquid crystal layer 55. The manufacturing method of the alignment films 34 and 44 is not specifically limited. The first alignment film 34 and the second alignment film 44 having liquid crystal alignment ability can be formed by any method. For example, the alignment films 34 and 44 may be produced by rubbing a resin layer such as polyimide, or the polymer film is irradiated with linearly polarized ultraviolet rays to selectively select the polymer chains in the polarization direction. The alignment films 34 and 44 may be produced based on the photo-alignment method to be reacted. Instead of the alignment layer and the photo-alignment layer by such a rubbing treatment, a fine line-shaped uneven shape produced by the rubbing treatment may be produced by a shaping treatment to produce the orientation layer.

  A liquid crystal layer 55 is provided between the first alignment film 34 and the second alignment film 44. The liquid crystal layer 55 includes a liquid crystal material 56. In the illustrated example, the VA mode is adopted, and the liquid crystal material 56 includes nematic liquid crystal having negative dielectric anisotropy. In the VA mode, the alignment of the liquid crystal molecules is regulated by the alignment ability of the alignment films 34 and 44 in a state where no voltage is applied between the pair of electrodes 33 and 43, and becomes a vertical alignment. At this time, the polarization state of the light transmitted through the liquid crystal layer 55 is maintained. On the other hand, when a voltage is applied between the pair of electrodes 33 and 43, the liquid crystal molecules are tilted under the control of an electric field. At this time, by passing through the liquid crystal layer 55, one linearly polarized light component becomes the other linearly polarized light component. That is, when the polarizing plates 31 and 41 are arranged in crossed Nicols, the light is transmitted (white display) in the applied state, and the light is blocked (black display, normally black) in the non-applied state.

  Next, the sealing material 51 will be described. As shown in FIG. 1, a sealing material 51 is provided between the pair of substrates 30 and 40. As shown in FIG. 7 to be described later, the sealing material 51 surrounds the liquid crystal layer 55 in a circumferential shape. That is, the sealing material 51 defines the liquid crystal layer 55 that is filled with the liquid crystal material 56. The sealing material 51 serves to prevent leakage of the liquid crystal material 56 constituting the liquid crystal layer 55 from between the pair of substrates 30 and 40, and the first substrate 30 (first alignment film 34) and the second substrate 40 (first It adheres to the two-alignment film 44) and serves to fix them together.

  Although details will be described later with reference to FIGS. 7 and 8, the peripheral edges 39 and 49 of at least one of the substrates 30 and 40 are regions more than half the circumference of the sealing material 51 and are more outward than the sealing material 51. positioned. With such a configuration, the in-plane variation in applied voltage can be suppressed, and the in-plane variation in transmittance can be effectively made inconspicuous. Note that the outside of the sealing material refers to the side opposite to the side surrounded by the sealing material 51 (that is, the liquid crystal layer 55 side) with respect to the sealing material 51.

  Generally, the sealing material 51 can be formed using a thermosetting epoxy resin. In particular, when the filling method of the liquid crystal material 56 between the pair of substrates 30 and 40 is a vacuum injection method, the sealing material 51 made of epoxy resin can be suitably used. When the ODF (One Drop Fill) method is used as the filling method of the liquid crystal material 56, a hybrid type material having both thermosetting property and UV curable property (ultraviolet curable property) is preferably used as the sealing material 51. it can. This is because when the liquid crystal material 56 touches the sealing material 51 before being cured, an appearance defect is induced. Therefore, it is preferable that the sealing material 52 (composition component of the sealing material 51) constituting the sealing material 51 includes, for example, an ultraviolet curable acrylic resin and an epoxy resin.

  Next, the spacer 50 will be described. The spacer 50 is disposed between the first resin base material 32 of the first substrate 30 and the second resin base material 42 of the second substrate 40. The spacer 50 secures a space between the first resin base material 32 and the second resin base material 42. A liquid crystal layer 55 is formed by filling the space with a liquid crystal material 56. The liquid crystal layer 55 described above controls the amount of phase modulation of transmitted light, and therefore needs to have a certain thickness between the pair of substrates 30 and 40. The plurality of spacers 50 are discretely arranged in a region between the pair of resin base materials 32 and 42. Each spacer 50 can be made of various resin materials, and may have a shape such as a frustum (for example, a truncated cone or a truncated pyramid), or may have a spherical bead shape. The columnar spacer 50 can be formed at a desired location using a photolithographic technique, and the bead-shaped spacer may be dispersed and applied to liquid crystal or alignment film ink in addition to the spraying method.

  In the example shown in FIG. 2, in the first substrate 30, the first alignment film 34 extends adjacent to the first electrode 33 and extends along the first electrode 33. That is, the first alignment film 34 is provided adjacent to the first electrode 33 in a planar shape. On the other hand, in the second substrate 40, the spacer 50 is provided between the second alignment film 44 and the second electrode 43. The second alignment film 44 extends along the second electrode 43 and the spacer 50. That is, the surface of the second alignment film 44 opposite to the liquid crystal layer 55 is in contact with either the second electrode 43 or the spacer 50. In the example of FIG. 2, the first alignment film 34 of the first substrate 30 and the second alignment film 44 of the second substrate 40 are in contact with each other on the spacer 50. Although the spacer 50 is located between the pair of resin base materials 32 and 42, the spacer 50 is located not in the pair of substrates 30 and 40 but in the second substrate 40.

  However, the spacer 50 is not limited to the example of FIG. 2, and the spacer 50 may be disposed between the pair of substrates 30 and 40 as in the example shown in FIG. 3, for example. In the example shown in FIG. 3, like the first alignment film 34, the second alignment film 44 extends adjacent to the second electrode 43 and extends along the second electrode 43.

  Next, an example of the manufacturing method of the light control cell 20 having the above configuration will be described with reference to FIGS.

  First, as shown in FIG. 4, a second substrate 40 and a spacer 50 are prepared. The second substrate 40 can be produced, for example, as follows. First. A second electrode 43 is formed on the second resin substrate 42 by sputtering or the like. Next, the composition that forms the second alignment film 44 is applied on the second alignment film 44, and then the alignment regulating force is applied to the coating film by rubbing, photo-alignment, etc. 44 is produced. Then, the 2nd board | substrate 40 is obtained by bonding the 2nd polarizing plate 41 to the 2nd resin-made base materials 42. FIG. The spacer 50 can be manufactured using a photolithography technique. When the dimming cell 20 shown in FIG. 2 is manufactured, the spacer 50 is formed on the second electrode 43 before the second alignment film 44. When the light control cell 20 shown in FIG. 3 is manufactured, the second alignment film 44 is formed on the second electrode 43 before the spacer 50.

  Next, as shown in FIG. 5, the sealing material 52 is applied in a circumferential shape. The sealing material 52 is a material having adhesiveness or tackiness. The seal material 52 is cured to form the seal material 51. Thereafter, as shown in FIG. 6, a liquid crystal material 56 containing liquid crystal molecules is supplied to a region on the second substrate 40 surrounded by the sealing material 51.

  Next, the first substrate 30 is stacked on the second substrate 40 under reduced pressure. Thereafter, the sealing material 52 is deformed and cured, and the first substrate 30 and the second substrate 40 are joined together, whereby the light control cell 20 is obtained. In addition, when laminating | stacking the 1st board | substrate 30 on the 2nd board | substrate 40, you may make it iron using a roller etc.

  In the dimming cell 20 thus obtained, the orientation of the liquid crystal molecules in the liquid crystal layer 55 can be controlled by applying a voltage from the dimming controller 12 to the electrodes 33 and 43. By changing the orientation of the liquid crystal molecules, the amount of phase modulation of light when passing through the liquid crystal layer 55 changes. Thereby, the transmittance of light transmitted through the first substrate 30, the liquid crystal layer 55, and the second substrate 40 can be changed.

  By the way, as already described as a conventional defect, when a region (pixel region) for adjusting the transmittance of the light control cell 20 is widened, in-plane variation in voltage occurs when voltage is applied to the electrodes in this region. The in-plane variation of the applied voltage makes the alignment of liquid crystal molecules driven by voltage application non-uniform in the plane. The transmittance adjusting function in the light control cell 20 depends on the orientation of liquid crystal molecules in the liquid crystal layer 55. Therefore, when the alignment of the liquid crystal molecules becomes non-uniform in the plane, the transmittance of the light control cell 20 also varies in the plane. The electrodes 33 and 43 that ensure transparency, for example, the transparent electrodes 33 and 43 made of a metal oxide, have a relatively large sheet resistance. In a region separated from the connection portions 38 and 48 connected to the external power source, the alignment control with respect to the liquid crystal molecules becomes insufficient, and the response speed also decreases. For this reason, when an AC power source having a high frequency is used, a fatal problem may occur for the dimming cell 20 in which the transmittance cannot be adjusted sufficiently in a region far from the connecting portions 38 and 48.

  Conventionally, the electrode has spread to a region facing the liquid crystal layer and a connection portion for connecting to an external power source (in the illustrated example, the dimming controller 12). That is, at the connection portion, the electrode sometimes extends beyond the sealing material.

  On the other hand, as shown in FIGS. 7 and 8, in this embodiment, the peripheral edges 39 and 49 of at least one of the substrates 30 and 40 are regions that are more than half the circumference of the sealing material 51 and are more outward than the sealing material 51. Is located. That is, the peripheral edges 39 and 49 of at least one of the substrates 30 and 40 extend beyond the sealing material 51 to a region that does not face the liquid crystal layer 55 in a region that is half or more of the peripheral length. In particular, in the illustrated example, the peripheral edges 39 and 49 of both the substrates 30 and 40 are located outside the sealing material 51 in a region that is more than half the circumference of the sealing material 51. Therefore, as shown in FIG. 8, the electrodes 33 and 43 can be arranged in a region outside the seal material 51. As a result, it is possible to use the electrodes 33 and 43 located outside the sealing material 51 that could not be used so far, and to connect to an external power source (the dimming controller 12 in the illustrated example). Current can flow through various paths even at positions far away from the connecting portions 38 and 48.

  Further, in the illustrated example, the peripheral edges 39 and 49 of at least one of the substrates 30 and 40 are located outward from the sealing material 51 over the entire circumference. In particular, in the illustrated example, the peripheral edges 39 and 49 of both substrates 30 and 40 are located outward from the sealing material 51 over the entire circumference. For example, as shown in FIG. 7, a current path cp that flows through the electrodes 33 and 43 in a region outside the sealing material 51 that has not been used so far and reaches a position far from the connection portions 38 and 48. Can be secured. As a result, in the light control device 10 and the light control cell 20, even when the region (pixel region) where the alignment of the liquid crystal molecules should be changed at a time becomes large, the alignment of the liquid crystal molecules can be stably controlled. Also, the response speed can be effectively improved.

  In order to secure a current path from the connecting portions 38, 48 to the position farthest away from the connecting portions 38, 48 outside the sealing material 51, the peripheral edge 39 of at least one of the substrates 30, 40. 49, more preferably, the peripheral edges 39, 49 of both the substrates 30, 40 are located outside the sealing material 51 in a region where the sealing material 51 is a continuous half or more. In this case, although depending on the positions of the connecting portions 38 and 48, the electrodes 33 and 48 located outward from the sealing material 51 from the connecting portions 38 and 48 to the position farthest away from the connecting portions 38 and 48. 43 can also be connected.

  Such an effect is particularly useful for an electrode using a transparent conductor made of a metal oxide that increases sheet resistance. As a result of confirmation by the present inventor, even in the light control cell 20 (light control device 10) using an electrode having a sheet resistance of 100Ω / □ or more and 1000Ω / □ or less, the above-described configuration can be used to reduce the transmittance. It was possible to sufficiently reduce the in-plane variation of the transmittance, specifically, to reduce the in-plane variation of the transmittance to such an extent that the variation of the brightness and the darkness are not felt visually.

Similarly, when the region intended to control the alignment of the liquid crystal molecules, that is, the region of the electrodes 33 and 43 that faces the liquid crystal layer 55 becomes wide, variation in transmittance is likely to occur. As for this point, the present inventors confirmed that the maximum distance d _max (see FIG. 7) between any two points in the region facing the liquid crystal layer 55 of the electrodes 33 and 43 is 20 cm or more and 150 cm or less. Even in the dimming cell 20 (the dimming device 10), the above-described configuration can be used to sufficiently reduce the in-plane variation of the transmittance. Specifically, the variation in brightness and the darkness can be visually observed. It was possible to reduce the in-plane variation in transmittance to such an extent that no variation was felt.

Similarly, the shortest along the current path from the connection regions 33a, 43a of the electrodes 33, 43 connected to the external power source to any position in the region of the electrodes 33, 43 facing the liquid crystal layer 55. Regarding the length, when the difference between the longest length l _max (see FIG. 7) and the shortest length l _min (see FIG. 7) becomes large, it becomes easy to cause variation in transmittance. In this regard, where the present inventor has confirmed, the length _{l max} even the shortest and becomes length _l difference 20cm or 150cm hereinafter become dimmer cell 20 (dimmer 10) between _min which is the longest, By adopting the above-mentioned configuration, the in-plane variation of the transmittance is sufficiently reduced, specifically, the in-plane of the transmittance to such an extent that the brightness variation and the darkness variation are not felt visually. The variation could be reduced.

  From the viewpoint of sufficiently reducing the in-plane variation of the transmittance, the width t1 (see FIG. 7) of the portion located outside the sealing material 51 of the substrates 30 and 40 and the electrodes 33 and 43 The width t2 (see FIG. 7) of the portion located outward from the sealing material 51 is preferably not less than 0.5 cm and not more than 5 cm. If the width t1 and the width t2 are smaller than 0.5 cm, the in-plane variation of the applied voltage may not be sufficiently reduced. On the other hand, when the width t1 and the width t2 are larger than 5 cm, the base materials 30 and 40 including the resin base materials 31 and 41 and the electrodes 33 and 43 are bent, causing a short circuit of the electrodes 33 and 43.

  Incidentally, in the example shown in FIGS. 7 and 8, the first substrate 30 includes a first connection portion 38 that forms a connection portion with an external power source (in the illustrated example, the dimming controller 12). In the first connection portion 38, a connection member 65 that communicates with an external power source (in the illustrated example, the dimming controller 12), for example, FPC (Flexible Printed Circuits), is disposed on the exposed first electrode 33. One electrode 33 is electrically connected to the connection member 65. Therefore, the region where the first electrode 33 and the connection member 65 are electrically connected forms the connection region 33a described above. The first substrate 30 includes the first connection portion 38 and extends beyond the seal material 51 on the entire periphery thereof. The first electrode 33 also includes a connection region 33a and extends beyond the seal material 51 on the entire circumference.

  Similarly, as shown in FIGS. 7 and 8, the second substrate 40 includes a second connection portion 48 that forms a connection portion with an external power source (in the illustrated example, the dimming controller 12). In the second connection portion 48, a connection member 65 that communicates with an external power source (in the illustrated example, the dimming controller 12), for example, FPC (Flexible Printed Circuits), is disposed on the exposed second electrode 43. The two electrodes 43 are electrically connected to the connection member 65. Therefore, the region where the second electrode 43 and the connection member 65 are electrically connected forms the connection region 43a described above. The second substrate 40 includes the second connection portion 48 and extends beyond the seal material 51 on the entire circumference thereof. The second electrode 43 also includes the connection region 43a and extends beyond the seal material 51 on the entire circumference.

  That is, in the example shown in FIG. 7 and FIG. 8, the peripheral edges 39 and 49 of both the first substrate 30 and the second substrate 40 are located outward from the sealing material 51 over the entire periphery. ing. According to such a configuration, the in-plane variation of the applied voltage can be more effectively suppressed, and the in-plane variation of the transmittance can be more effectively inconspicuous.

  In the example shown in FIG. 8, the alignment films 34 and 44 are disposed only in a region facing the liquid crystal layer 55. However, as indicated by dotted lines in FIG. 8, the alignment films 34 and 44 may also extend beyond the sealing material 51 to a region that does not face the liquid crystal layer 55. In the region that does not face the liquid crystal layer 55, the alignment films 34 and 44 do not exhibit the alignment regulating function, but may function as an insulating layer that avoids electrical contact between the electrodes 33 and 43, for example.

  In the embodiment described above, the dimming cell 20 is the dimming cell 20 having a variable transmittance, and includes the first substrate 30 and the second substrate 40, and the first substrate 30 and the second substrate 40. A liquid crystal layer 55 provided therebetween, and a sealing material 51 located between the first substrate 30 and the second substrate 40 and surrounding the liquid crystal layer 55 in a circumferential shape are provided. At least one of the first substrate 30 and the second substrate 40 includes electrodes 33 and 43, and according to the degree of voltage application to the electrodes 33 and 43, that is, according to the applied voltage amount, The transmittance of light transmitted through the first substrate 30, the liquid crystal layer 55, and the second substrate 40 can be changed. The peripheral edges 39 and 49 of at least one of the substrates 30 and 40 are located outside the sealing material 51 in a region that is more than a half circumference of the sealing material 51. According to such a light control cell 20, the in-plane variation of the applied voltage can be suppressed, and the in-plane variation of the transmittance can be effectively made inconspicuous.

  Although the present invention has been described based on one embodiment shown in the drawings, the present invention is not limited to the above-described embodiment, and various aspects to which various modifications that can be conceived by those skilled in the art have been added. The effects produced by the present invention are not limited to those described above. Therefore, various additions, modifications, and partial deletions can be made to each element described in the claims and the specification without departing from the technical idea and spirit of the present invention.

  For example, in the above-described embodiment, an example in which the peripheral edges 39 and 49 are located outward from the sealing material 51 over the entire circumference of both the first substrate 30 and the second substrate 40 is shown. However, it is not limited to this example. Even in an example in which at least one of the peripheral edges 39 and 49 of the first substrate 30 and the second substrate 40 is located outside the sealing material 51 in an area that is equal to or more than half of the circumference, the in-plane variation of the applied voltage is also reduced. It is possible to suppress the in-plane variation of the transmittance effectively and inconspicuously.

  For example, in the example shown in FIGS. 9 and 10, the peripheral edge 39 of the first substrate 30 is located on the sealing material 51 in a portion other than the first connection portion 38. On the other hand, the peripheral edge 49 of the second substrate 40 is located outward from the sealing material 51 over the entire periphery. Even in such a modification, the reliability of the light control device 10 and the light control cell 20 can be improved by sufficiently exhibiting the short-circuit prevention function.

DESCRIPTION OF SYMBOLS 10 Light control apparatus 12 Light control controller 14 Sensor apparatus 16 User operation part 20 Light control cell 30 1st board | substrate 31 1st polarizing plate 32 1st resin-made base material 33 1st electrode 33a Connection area 34 1st alignment film 38 1st Connection part 39 Perimeter 40 Second substrate 41 Second polarizing plate 42 Second resin base material 43 Second electrode 43a Connection region 44 Second alignment film 48 Second connection part 49 Perimeter 50 Spacer 51 Sealing material 52 Sealing material 55 Liquid crystal layer 56 Liquid crystal material 59 Tool 65 Connection member

Claims (7)

A dimming cell with variable transmittance,
A first substrate including a first resin substrate;
A second substrate including a second resin base material;
A liquid crystal layer provided between the first substrate and the second substrate;
A sealant positioned between the first substrate and the second substrate and surrounding the liquid crystal layer in a circumferential shape,
At least one of the first substrate and the second substrate includes an electrode;
The light control cell, wherein the peripheral edge of the at least one substrate is located outside the sealing material in a region that is not less than a half circumference of the sealing material.   2. The light control cell according to claim 1, wherein a peripheral edge of the at least one substrate is located outside the sealing material in a region that is a continuous half or more of the sealing material.   In a region where the peripheral edge of the first substrate is more than a half circumference of the sealing material, located outside the sealing material, and the peripheral edge of the 21st substrate is a half circumference or more of the sealing material. The light control cell according to claim 1, wherein the light control cell is located outward from the sealing material.   The light control cell according to any one of claims 1 to 3, wherein a peripheral edge of the at least one substrate is located outward from the sealing material over the entire periphery.   The light control cell according to claim 1, wherein the electrode has a sheet resistance of 100Ω / □ or more and 1000Ω / □ or less.   The light control cell as described in any one of Claims 1-5 whose maximum distance between arbitrary two points in the area | region which faces the said liquid-crystal layer among the said electrodes is 20 cm or more and 150 cm or less. The electrode includes a connection region with an external power source,
Regarding the length along the current path from the connection region to an arbitrary position in the region of the electrode facing the liquid crystal layer, the difference between the longest length and the shortest length is 20 cm or more. The light control cell as described in any one of Claims 1-6 which is 150 cm or less.

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