Light-adjusting component, method for manufacturing light-adjusting component, light-adjusting body, and vehicle

Abstract

The present invention provides a dimming component and a method for manufacturing the dimming component with a strong fixing force between an orientation layer and a beaded spacer. The dimming component (1) of the present invention is characterized in that it includes: a first stack (12), which includes a substrate (21A) and an orientation layer (23A); a second stack (13), which includes a substrate (21B) and an orientation layer (23B), and is configured relative to the first stack (12) so that the orientation layers are opposite to each other; a liquid crystal layer (14), which is configured between the first stack (12) and the second stack (13), and the orientation is provided on the first stack (12); 12) and the second stack (13) are controlled by driving the electrodes of at least one of the electrodes; and a plurality of bead-like spacers (24) are arranged in the liquid crystal layer; in the orientation layer (23A) of the first stack (12) and the orientation layer (23B) of the second stack (13), a plurality of protrusions (30) protruding toward the liquid crystal layer (14) side are formed, and at least a portion of the bead-like spacers (24) is retained by the protrusions (30).

Description

Technical Field

[0001] The present invention relates to a dimming member, a method for manufacturing the dimming member, a dimming body, and a vehicle. Background Art

[0002] In the past, various measures have been proposed, such as dimming components that are attached to windows to control the transmission of external light (Patent Documents 1 and 2). Among such dimming components, there is a dimming component that uses liquid crystal. The dimming component that uses liquid crystal sandwiches liquid crystal between two transparent substrates with transparent electrodes, and applies a voltage between the transparent electrodes to change the orientation of liquid crystal molecules to control the transmittance of external light.

[0003] In such a light control member, a spacer is provided between transparent substrates, and the liquid crystal layer is maintained at a desired thickness by the spacer.

[0004] Here, bead-shaped spacers may be used as spacers. Generally, bead-shaped spacers are spread on the surface of a transparent substrate on which an alignment layer is formed, and a sealing material is formed around the surface, followed by lamination and vacuum injection of liquid crystal.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 03-47392

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 08-184273 Summary of the invention

[0009] [Problems to be solved by the invention]

[0010] Here, when the transparent substrate is a glass substrate, since the liquid crystal is injected in a state where the bead spacer is sandwiched between the transparent substrates, the bead spacer is unlikely to move.

[0011] However, in the case of dripping liquid crystal before laminating the transparent substrate, if the adhesion of the bead spacer to the substrate is weak, the bead spacer may move due to the flow of liquid crystal. When the bead spacer moves, the thickness of the liquid crystal may become uneven, resulting in rainbow spots, etc.

[0012] Furthermore, unlike a television or the like, when the dimming member is used in an environment where vibrations are often applied, such as in a vehicle, the bead spacers are more likely to move.

[0013] In particular, when the transparent substrate is a film, the pressing force between the transparent substrates becomes weak at the location where the transparent substrate is loose, and the bead-shaped spacer is easy to move. When the light-adjusting member is attached to a curved surface, the tendency of such movement becomes stronger.

[0014] A method of providing a fixing layer on the bead-shaped spacer to improve the adhesion has also been adopted. However, when the fixing layer is thick, the fixing layer will be crushed when it is attached to the transparent substrate, and the thickness of the liquid crystal layer will become sparse, especially in the VA (Vertical Alignment) method that is sensitive to the thickness of the liquid crystal layer, unevenness is likely to occur.

[0015] An object of the present invention is to provide a dimming component having a strong fixing force between an alignment layer and a beaded spacer, a method for manufacturing the dimming component, a dimming body, and a vehicle.

[0016] [Technical solutions for solving technical problems]

[0017] (1) A dimming component, characterized in that it includes: a first stack including a substrate and an orientation layer; a second stack including a substrate and an orientation layer, and arranged relative to the first stack so that the orientation layers are opposite to each other; a liquid crystal layer arranged between the first stack and the second stack, and the orientation of which is controlled by driving an electrode provided in at least one of the first stack and the second stack; and a plurality of bead-shaped spacers arranged in the liquid crystal layer; a plurality of protrusions protruding toward the liquid crystal layer are formed on the orientation layer of at least one of the orientation layers of the first stack and the second stack, and at least a part of the bead-shaped spacers is held by the protrusions.

[0018] (2) A light control member, characterized in that, in (1), the alignment layer includes a covering portion covering the surface of the bead-shaped spacer held by the convex portion.

[0019] (3) A light control member, characterized in that, in (1) or (2), each substrate of the first stack and the second stack is a resin film, and the liquid crystal layer contains a dichroic dye.

[0020] (4) A light control member according to any one of (1) to (3), wherein, among the plurality of bead spacers arranged in the liquid crystal layer, an aggregation ratio of the bead spacers aggregated in a number of not less than 2 and not more than 4 is not less than 20%.

[0021] (5) A dimming component characterized in that, in any one of (1) to (4), a hard coating layer is provided on a surface of at least one of the substrates provided on the first stack and the second stack on the side of the liquid crystal layer.

[0022] (6) A dimming component characterized in that, in any one of (1) to (5), the bead spacer is spherical, and when the diameter of the bead spacer is denoted by R and the maximum diameter of the portion of the bead spacer held in the convex portion is denoted by r, 0.8≤r / R.

[0023] (7) A light control member according to any one of (1) to (6), characterized in that the interior of the convex portion is filled with a material of the alignment layer or a resin component derived from a bead-like spacer.

[0024] (8) A method for manufacturing a dimming component, characterized in that the manufacturing process of the dimming component includes: a first stack manufacturing process, which forms an orientation layer on a substrate to produce a first stack; a second stack manufacturing process, which forms an orientation layer on a substrate to produce a second stack; a sealing portion forming process, which forms a sealing portion on the outer periphery of the above-mentioned second stack; a liquid crystal inflow process, which allows the liquid crystal to flow into the interior of the above-mentioned sealing portion; and a stacking process, which stacks the above-mentioned first stack and the second stack; in the manufacturing process of the dimming component, at least one of the material forming the orientation layer of the above-mentioned first substrate and the material forming the orientation layer of the above-mentioned second substrate contains a bead-shaped spacer.

[0025] (9) A method for manufacturing a light control member, characterized in that, in (8), both materials forming the alignment layer of the first substrate and the alignment layer of the second substrate contain bead-like spacers.

[0026] (10) A method for manufacturing a dimming component, characterized in that in (8) or (9), the stacking body manufacturing process in which an orientation layer is formed using a material containing the bead-like spacer in the first stacking body manufacturing process and the second stacking body manufacturing process includes the process of forming the orientation layer twice.

[0027] (11) A light modulator includes a transparent member and the light modulating member according to any one of (1) to (7) disposed on the transparent member.

[0028] (12) A vehicle, wherein the light control member according to any one of (1) to (7) is disposed at a location where external light is incident.

[0029] [Effects of the invention]

[0030] According to the present invention, a light control member having a strong fixing force between an alignment layer and a bead-shaped spacer and a method for manufacturing the light control member can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 1 is a cross-sectional view showing a light control film 1 as one embodiment of a light control member.

[0032] Figure 2 1 is a flowchart showing a manufacturing process of the light control film 1 .

[0033] Figure 3 The second laminate 13 ′ of Comparative Example 3 is shown.

[0034] Figure 4 It is a cross-sectional view showing a light control film 1 according to a second embodiment. DETAILED DESCRIPTION

[0035] (First embodiment)

[0036] (Dimming Film)

[0037] Figure 1 It is a cross-sectional view showing a light control film 1 as one embodiment of the light control member of the present invention.

[0038] The light-adjusting film 1 of this embodiment is formed into a flexible film as one mode of light-adjusting means and is attached to a curved portion such as a sun roof of a vehicle and can be switched between transmissive and opaque.

[0039] As described above, the dimming film 1 is disposed on a transparent member such as a car sunroof and is mainly used as a dimming body. More specifically, the dimming film 1 can be used as a dimming body of laminated glass by being attached to a transparent member such as a transparent resin plate or glass by an adhesive or the like, or by being sandwiched between glass plates (transparent members).

[0040] The dimming film 1 (dimming component) is, for example, arranged on the window glass or display cabinet of a building, the transparent partition in the house, the window of a vehicle, etc., where dimming is sought (the part where external light is incident, such as the front or side, rear, top, etc. windows), so as to control the amount of light incident on the inner side of the building or vehicle, etc.

[0041] The dimming film 1 is a dimming film 1 that controls transmitted light using liquid crystal 14A, and is composed of a first stack 12 and a second stack 13 that sandwich a liquid crystal layer 14. A spacer 24 is provided between the first stack 12 and the second stack 13 to keep the thickness of the liquid crystal layer 14 constant. The first stack 12 and the second stack 13 are formed by sequentially forming a first transparent electrode 22A, a second transparent electrode 22B, a first orientation layer 23A, and a second orientation layer 23B on a first substrate 21A and a second substrate 21B, respectively.

[0042] In the case of the IPS system described later, the first transparent electrode 22A and the second transparent electrode 22B are collectively manufactured on one of the first orientation layer 23A and 23B sides.

[0043] Furthermore, the light control film 1 controls the transmission of external light by changing the potential difference between the first transparent electrode 22A and the second transparent electrode 22B.

[0044] (Base material)

[0045] The first substrate 21A and the second substrate 21B can use various laminates such as TAC (triacetyl cellulose), polycarbonate film, COP (cycloolefin polymer), acrylic, and PET (polyethylene terephthalate) that have light transmittance and flexibility suitable for the dimming film 1. In this embodiment, a film material made of polycarbonate with a hard coating on both sides is used.

[0046] (Transparent Electrode)

[0047] The first transparent electrode 22A and the second transparent electrode 22B are respectively formed of transparent conductive films laminated on the first substrate 21A and the second substrate 21B.

[0048] As the transparent conductive film, various transparent electrode materials suitable for such transparent resin films can be used, and examples thereof include oxide-based transparent metal thin films having a total light transmittance of 50% or more, such as tin oxide-based, indium oxide-based, and zinc oxide-based.

[0049] Examples of tin oxide (SnO 2 )-based materials include nesoi (tin oxide; SnO 2 ), ATO (Antimony Tin Oxide: antimony-doped tin oxide), and fluorine-doped tin oxide.

[0050] Examples of indium oxide (In 2 O 3 )-based materials include indium oxide, ITO (Indium Tin Oxide), and IZO (Indium Zinc Oxide).

[0051] Examples of zinc oxide (ZnO)-based materials include zinc oxide, AZO (aluminum-doped zinc oxide), and gallium-doped zinc oxide.

[0052] In this embodiment, the transparent conductive film is formed using ITO (Indium Tin Oxide).

[0053] Here, a hard coating layer (not shown) may be provided on the surface of at least one side of each substrate 21A, 21B where the liquid crystal layer 14 is provided (between the first substrate 21A and the first transparent electrode 22A, between the second substrate 21B and the second transparent electrode 22B). By providing a hard coating layer on each substrate, when an external force is applied to the surface of the dimming film 1, the bead-shaped spacer 24 sandwiched between the substrates can be prevented from entering the substrates, and the substrates can be prevented from being sunken or broken, and the pressure resistance of the dimming film 1 can be improved. The hard coating layer may be formed of an acrylic resin, a urethane resin, a silicone resin, etc., and various functions such as antistatic, ultraviolet absorption, and infrared absorption may be added as needed.

[0054] The hard coat layer may be provided on at least one of the first substrate 21A and the second substrate 21B, and may be provided not only on the surface of the substrate on the liquid crystal layer 14 side but also on the surface on the opposite side.

[0055] Furthermore, a refractive index matching layer for adjusting the refractive index may be further provided between the hard coat layer and the transparent electrode 22 . Furthermore, the function of adjusting the refractive index may be provided in the hard coat layer so that the hard coat layer also serves as the refractive index matching layer.

[0056] (Orientation Layer)

[0057] The first orientation layer 23A and the second orientation layer 23B are formed by a photo-orientation layer. The photo-orientation material applicable to the photo-orientation layer can be widely applicable to various materials applicable to the photo-orientation method, but in this embodiment, for example, a photo-dimerization type material is applicable. The photo-dimerization type material is disclosed in "M. Schadt, K. Schmitt, V. Kozinkov and V. Chigrinov: Jpn. J. Appl. Phys., 31, 2155 (1992)" and "M. Schadt, H. Seiberle and A. Schuster: Nature, 381, 212 (1996)".

[0058] In addition, the first orientation layer 23A and the second orientation layer 23B may be manufactured by rubbing treatment instead of the photo-orientation layer. In this case, after manufacturing various material layers such as polyimide that can be applied to the orientation layer, the first orientation layer 23A and the second orientation layer 23B are formed as follows: the surface of the material layer is rubbed using a rubbing roller to manufacture fine linear concave-convex shapes.

[0059] Instead of the alignment or photo-alignment by rubbing treatment, a fine linear concavo-convex shape produced by rubbing treatment may be produced by shaping treatment to produce an alignment layer.

[0060] In addition, the formation of the linear concavo-convex shape may be omitted in the first orientation layer 23A and the second orientation layer 23B formed of various materials applicable to the orientation layer such as polyimide.

[0061] (Spacer)

[0062] In this embodiment, a spherical bead spacer 24 is used as a spacer. The bead spacer 24 is used to limit the thickness of the liquid crystal layer 14. The bead spacer 24 can be widely applied to a structure formed of an inorganic material such as silicon dioxide, a structure formed of an organic material, and a core-shell structure formed by combining the two. In addition, in addition to the spherical structure, it can also be composed of a rod shape such as a cylindrical shape and a prism shape.

[0063] Furthermore, in addition to the above-mentioned bead-shaped spacers 24 , the liquid crystal layer 14 may include spacers other than the bead-shaped spacers, for example, spacers formed by photolithography or printing.

[0064] (Liquid crystal layer)

[0065] The liquid crystal layer 14 can be widely applied to various liquid crystals 14A applicable to the light-adjusting film 1. In addition, in the present embodiment, the liquid crystal layer 14 is a guest-host type liquid crystal 14A mixed with a dichroic pigment. The dichroic pigment moves along with the movement of liquid crystal molecules, thereby controlling the transmission and shielding of light.

[0066] As the liquid crystal 14A, a TN liquid crystal (twisted Nematic liquid crystal) 14a is used. When the TN liquid crystal is used as the "host" and the dichroic dye is used as the "guest", when no voltage is applied, the dimming film is a so-called normally black type in which the liquid crystal molecules and the dichroic dye are arranged horizontally and light is blocked, so that the screen becomes "black". When the voltage is gradually applied, the liquid crystal molecules stand up vertically, and the dichroic dye also stands upright, so that light is transmitted. In addition, for this liquid crystal 14A, in addition to the above-mentioned TN liquid crystal, a VA liquid crystal can also be used. In the case of the guest-host VA type, the liquid crystal molecules and the dichroic dye are arranged vertically when no voltage is applied, so that light can be transmitted.

[0067] However, the present invention is not limited to this, and as the liquid crystal 14A and the dye used in the guest-host system, a mixture of the liquid crystal 14A and the dye proposed for the guest-host system can be widely applied.

[0068] Furthermore, not limited to the guest-host method, a liquid crystal layer composed of a liquid crystal material that does not contain a dichroic pigment may also be used. In this case, for driving the liquid crystal layer 14, not only the above-mentioned TN method but also the VA (Vertical Alignment) method may be used. The VA method is a method of controlling the transmitted light by changing the orientation of the liquid crystal 14A between the vertical orientation and the horizontal orientation. The method is configured as follows: when there is no electric field, the liquid crystal 14A is vertically oriented, so that the liquid crystal layer 14 is sandwiched by the vertical orientation layer to form the dimming film 1, and the liquid crystal 14A is horizontally oriented by applying an electric field. In the case of the VA method, the screen generally becomes "black" when no voltage is applied, which is the so-called normally black type.

[0069] In addition, an IPS (In-Plane-Switching) method may also be used. The IPS method is a driving method in which transparent electrodes for driving are concentrated on one of a pair of substrates sandwiching the liquid crystal layer 14, and the transparent electrodes are used to form an electric field in the in-plane direction of the substrate surface, namely, a so-called transverse electric field, thereby controlling the orientation of the liquid crystal 14A.

[0070] The sealing material 25 is formed in a frame shape so as to surround the liquid crystal layer 14. The sealing material 25 is fixed to the first stacked body 12 and the second stacked body 13, and the sealing material 25 prevents leakage of the liquid crystal 14A.

[0071] (Manufacturing process)

[0072] Figure 21 is a flowchart showing a manufacturing process of the light control film 1 .

[0073] First, in the first stacked body manufacturing step SP2, the first stacked body 12 is manufactured. The first stacked body manufacturing step SP2 includes a first electrode manufacturing step SP2-1 and a first orientation layer manufacturing step SP2-2.

[0074] In the first electrode manufacturing step SP2 - 1 , the first transparent electrode 22A formed of ITO is manufactured on the first substrate 21A by a vacuum film forming method such as sputtering.

[0075] In the first alignment layer manufacturing step SP2-2, a coating liquid for the first alignment layer 23A is applied by a gravure coater, and then the solvent component of the coating liquid is volatilized and dried in a drying furnace, thereby manufacturing the first alignment layer 23A.

[0076] In the subsequent second stack production step SP3, the second stack 13 is produced. The second stack production step SP3 includes a second electrode production step SP3-1 and a second orientation layer production step SP3-2.

[0077] In the second electrode manufacturing step SP2 - 1 , the second transparent electrode 22B formed of ITO is manufactured on the second base material 21B by a vacuum film forming method such as sputtering.

[0078] In the second orientation layer manufacturing process SP3-2, a gravure coater is used to apply a coating liquid for the second orientation layer 23B. In the coating liquid, bead spacers 24 are mixed in a manner of 150 per square millimeter. Next, the solvent component of the coating liquid is volatilized and dried in a drying furnace, thereby forming the second orientation layer 23B. The ratio of the area (projected area) occupied by the bead spacers 24 in the liquid crystal layer 14 is preferably in the range of 0.1% to 2.5% relative to the area of ​​the surface perpendicular to the thickness direction of the liquid crystal layer. If it is less than 0.1%, it is not preferred because the pressure resistance of the liquid crystal layer 14 described later will be reduced. In addition, if it exceeds 2.5%, it is not preferred because the transmittance of the light-transmitting film 1 in the light-transmitting state will be reduced.

[0079] In the sealing material applying step SP4 after the second stacked body manufacturing step SP3, a dispenser is used to apply the sealing material 25 in a frame shape onto the second stacked body 13. In the present embodiment, the sealing material 25 is a UV (ultraviolet) thermosetting resin.

[0080] Next, in the liquid crystal pouring step SP5 , the liquid crystal 14A is poured into the interior of the frame shape by a dropping method.

[0081] Then, in the lamination step SP6, the first laminate 12 and the second laminate 13 are laminated and pressed, so that the liquid crystal 14A arranged in the second laminate 13 is spread inside the sealing material 25 formed into a frame shape. Then, the sealing material 25 is cured by irradiation with ultraviolet rays, etc., thereby manufacturing the light-adjusting film 1.

[0082] In the arrangement of the liquid crystal 14A, various methods can be widely applied instead of the dropping method, for example, when the liquid crystal material is arranged in a gap formed at a relevant portion of the liquid crystal layer after the first stack 12 and the second stack 13 are stacked.

[0083] Here, the coating liquid of the second alignment layer 23B is applied onto the second transparent electrode 22B of the second substrate 21B in the second alignment layer manufacturing step SP3-2 in a mixed state with the bead spacers 24 as described above. Then, the solvent component of the coating liquid is volatilized and dried in a drying furnace.

[0084] Then, the water level (liquid level) of the coating liquid will drop. At this time, the water level (liquid level) of the coating liquid in contact with the bead spacer 24 will not decrease compared to other parts. Therefore, the surrounding of the bead spacer 24 is solidified in a form in which the second orientation layer 23B partially protrudes toward the liquid crystal layer 14 side, and covers the outer peripheral curved surface (surface) of the lower side (second substrate 21B side) of the bead spacer 24, so that the protrusion 30 is formed integrally with the second orientation layer 23B. Then, as Figure 1 As shown, the bead-like spacers 24 are held on the second orientation layer 23B by the protrusions 30 .

[0085] Thus, compared with the conventional case where bead spacers having a fixed layer are dispersed and arranged on the alignment layer, the light-adjusting film 101 can arrange the bead spacers 24 more strongly on the second alignment layer 23B and can minimize the movement of the bead spacers during the liquid crystal inflow process.

[0086] Here, in the past, regarding the bead spacer, a fixing layer (adhesive layer) is provided on its surface, and it is dispersedly arranged by spreading on the orientation layer formed roughly flat. In this case, because the bead spacer is fixed by point contact with respect to the orientation layer, a gap will be generated between the outer peripheral curved surface on the lower side of the bead spacer and the orientation layer. Therefore, in the liquid crystal inflow process (SP5), when the guest-host type liquid crystal containing a dichroic pigment is dripped on the orientation layer, the following situation may occur: because the guest-host type liquid crystal containing a dichroic pigment has a higher viscosity than the liquid crystal without a dichroic pigment, the liquid crystal cannot fully reach the above-mentioned gap, and air remains in the gap. The air remaining in the gap like this will generate bubbles in the liquid crystal layer due to heating in the lamination process (SP6) or temperature changes when the dimming film is used later, which becomes a factor in reducing the quality of the dimming film.

[0087] In addition, especially when a resin film is used as the substrate instead of a glass plate, when the resin film (substrate) is stretched by heating, etc., the air remaining in the above-mentioned gap will tend to concentrate in the liquid crystal layer, and the possibility of forming bubbles and being visible will increase.

[0088] Therefore, in the light-adjusting film 1 of the present embodiment, the bead-shaped spacers are held by the convex portions 30 provided on the second orientation layer 23B, so that Figure 1 As shown, the gap is filled with the alignment layer material (coating liquid). This can reduce the amount of air remaining in the liquid crystal layer due to the gap as much as possible, and can significantly suppress the generation of bubbles in the liquid crystal layer by heating in the lamination step SP6 or temperature changes when the dimming film is used later.

[0089] Regarding the dimming film 1 of the present embodiment, among the bead-shaped spacers arranged in the liquid crystal layer 14, the lower limit of the aggregation ratio of the bead-shaped spacers aggregated in a number of 2 or more and 4 or less is preferably 20% or more, more preferably 30% or more, and further preferably 40% or more. By making the aggregation ratio of the bead-shaped spacers aggregated in a number of 2 or more and 4 or less satisfy the above range, the pressure resistance of the liquid crystal layer 14 can be improved. That is, when an external force is applied to the dimming film 1 (liquid crystal layer 14), the aggregated bead-shaped spacers can be used to greatly suppress the liquid crystal layer from breaking and causing gap changes or damage. In particular, when the dimming film is clamped on a glass substrate to form a laminated glass, even if a large pressure is applied to the dimming film, the deformation of the dimming film (liquid crystal layer) can be suppressed as much as possible, and the thickness of the liquid crystal layer can be prevented from becoming uneven.

[0090] In the liquid crystal layer 14 , if the aggregation ratio of the bead-like spacers aggregated in the number of 2 to 4 is less than 20%, this is not preferable because the ratio of aggregated bead-like spacers is too small and the liquid crystal layer may be broken or damaged.

[0091] The aggregation ratio of the bead spacers refers to the ratio of the number S2 of aggregates of the bead spacers to the total number S1 of the bead spacers arranged in a predetermined region in the liquid crystal layer (100×S2 / S1[%]).

[0092] For example, the aggregation ratio of bead spacers aggregated in a number of 2 to 4 represents the ratio of the number of aggregates of bead spacers aggregated in a number of 2 to 4 to the total number S1 of bead spacers arranged in a predetermined region of the liquid crystal layer.

[0093] Here, the aggregate of bead-like spacers refers to an aggregate of a plurality of bead-like spacers.

[0094] In addition, the total number S1 of bead spacers is not counted based on the number of bead spacers constituting the aggregate, but is counted based on the number of aggregates, in the case of an aggregate containing bead spacers. For example, in a predetermined area in the liquid crystal layer, there are two unaggregated bead spacers and there is an aggregate of three bead spacers, the total number S1 of bead spacers in the predetermined area is the sum of the number of unaggregated bead spacers (2) and the number of aggregates (1), that is, 3.

[0095] Furthermore, among the bead-shaped spacers arranged in the liquid crystal layer 14, the upper limit of the aggregation ratio of the bead-shaped spacers aggregated in the number of 2 or more and 4 or less is preferably 80% or less, more preferably 70% or less, and further preferably 60% or less. By making the aggregation ratio of the bead-shaped spacers aggregated in the number of 2 or more and 4 or less satisfy the above range, the bead-shaped spacers can be uniformly dispersed in the liquid crystal layer, and the thickness of the liquid crystal layer can be suppressed from becoming uneven.

[0096] If the aggregation ratio exceeds 80%, the distribution of the bead spacers in the liquid crystal layer may become uneven, which is not preferred. In addition, if the aggregation ratio is greater than 80%, the aggregated bead spacers will block the light that is to be transmitted through the light-adjusting film 1 (liquid crystal layer 14) more than necessary, thereby reducing the amount of light transmitted through the light-adjusting film 1 in the light-transmitting state, which is not preferred.

[0097] Furthermore, among the bead-shaped spacers arranged in the liquid crystal layer 14, the upper limit of the aggregation ratio of the bead-shaped spacers aggregated in the number of 5 or more is preferably less than 15%, more preferably less than 10%, and further preferably less than 6%. By making the aggregation ratio of the bead-shaped spacers aggregated in the number of 5 or more satisfy the above range, the bead-shaped spacers can be uniformly dispersed in the liquid crystal layer, and the thickness of the liquid crystal layer can be suppressed from becoming uneven.

[0098] As described above, the light-adjusting film 1 of this embodiment uses the second orientation layer manufacturing step SP3-2 to coat the orientation layer material mixed with the bead spacers 24, thereby arranging the bead spacers 24 and manufacturing the orientation layer. In this case, since the bead spacers 24 tend to be easily aggregated during the drying process of the orientation layer, the aggregation ratio of the bead spacers aggregated in the number of 2 or more and 4 or less can be appropriately adjusted by adjusting the drying conditions (drying temperature or drying time, etc.) of the orientation layer.

[0099] Here, the details of the aggregation ratio of the dimming film obtained by using two types of bead spacers with different diameters to produce a dimming film that satisfies the above-mentioned range of aggregation ratio are shown in Table 1. In Table 1, the aggregation ratio is calculated based on the number of bead spacers counted and averaged in a rectangular area (1.5 mm×1.5 mm) at five locations (center and midpoints of four corners) on the surface of the dimming film 1 (liquid crystal layer 14).

[0100] [Table 1]

[0101]

[0102] Example 1-1 in Table 1 shows the aggregation ratio of the dimming film using bead spacers with a diameter of 6.2 μm. In this dimming film, as described above, by adjusting the drying conditions of the alignment layer, it was confirmed that the aggregation ratio of bead spacers with more than 2 aggregates was 47.1%, among which the aggregation ratio of bead spacers with a number of more than 2 and less than 4 aggregates was 43.9%, and the aggregation ratio of bead spacers with a number of more than 5 aggregates was 3.2%. The pressure resistance of the dimming film to external forces and the amount of transmitted light in the light-transmitting state were both at a level sufficient for products.

[0103] In addition, Example 1-2 in Table 1 shows the aggregation ratio of the dimming film using bead spacers with a diameter of 9.0 μm. In this dimming film, as described above, by adjusting the drying conditions of the alignment layer, it was also confirmed that the aggregation ratio of bead spacers with more than 2 aggregates was 60.4%, among which the aggregation ratio of bead spacers with a number of more than 2 and less than 4 aggregates was 55.2%, and the aggregation ratio of bead spacers with a number of more than 5 aggregates was 5.2%. The pressure resistance of the dimming film to external forces and the amount of transmitted light in the light-transmitting state were both at a level sufficient for products.

[0104] Comparative Example 1 in Table 1 shows the aggregation ratio of the dimming film using bead-shaped spacers with a diameter of 5.7 μm. In this dimming film, the aggregation ratio of bead-shaped spacers with more than 2 aggregates is 21.4%, among which the aggregation ratio of bead-shaped spacers with a number of more than 2 and less than 4 aggregates is 16.4%, and the aggregation ratio of bead-shaped spacers with a number of more than 5 aggregates is 5.0%. It can be confirmed that the dimming film of Comparative Example 1 is not as resistant to external forces as the dimming films of Examples 1-1 and 1-2 described above. This is believed to be due to the fact that the aggregation ratio (16.4%) of bead-shaped spacers with a number of more than 2 and less than 4 aggregates in the dimming film of Comparative Example 1 is lower than that of Examples 1-1 and 1-2.

[0105] The effect of the light control film 1 of the present embodiment in which the bead-shaped spacers 24 are held on the convex portions 30 of the second orientation layer 23B in this manner will be described below by comparison with a comparative example.

[0106] (Comparative Example 2)

[0107] First, Comparative Example 2 is described. In Comparative Example 2, the coating liquid used in the second orientation layer manufacturing step does not contain bead spacers. In Comparative Example 2, bead spacers having a commercially available fixing layer are dispersed on the second orientation layer and heat-treated to melt the fixing layer, and then the bead spacers are fixed on the second orientation layer by cooling, thereby preparing a sample.

[0108] Next, air was sprayed (air jet) onto the second substrate (before being laminated with the first substrate) using an air gun to determine the residual rate of the bead-shaped spacers.

[0109] The nozzle of the air gun is 2mm The distance between the air gun and the second substrate was 5 mm, and the spraying time was 15 sec.

[0110] The pressure of the jet is increased from 1kgf / cm 2 Starting from 1kg / cm2 each time 2 The pressure increases gradually, and when it exceeds 5kgf / cm2 In the case of 5kgf / cm, a significant decrease in the residual rate was confirmed in the bead-shaped spacer. 2 The residual rate of the bead spacers was 30%.

[0111] (Example 2 of this embodiment)

[0112] Air was sprayed (air jet) with an air gun onto the second substrate 21B (before being laminated with the first substrate) on which the second orientation layer 23B was formed, which was manufactured in the second laminate manufacturing step SP3, and the remaining rate of the bead spacers 24 was determined.

[0113] The nozzle of the air gun is 2mm The distance between the air gun and the second substrate was 5 mm, and the spraying time was 15 sec.

[0114] The pressure of the jet is increased from 1kgf / cm 2 1kg / cm2 each time 2 The pressure increases gradually, and when it exceeds 5kgf / cm 2 When the bead spacer 24 has a large residual rate, the maximum diameter of the portion of the bead spacer 24 held in the convex portion 30 is denoted as r (refer to Figure 1 ), when the ratio of r to R = r / R, if r / R = 1, the residual rate is 100%. Even if r / R = 0.6, good results are obtained compared with Comparative Example 2.

[0115] As described above, it has been confirmed that when the bead-like spacers 24 are mixed in the alignment layer as in the present embodiment, the adhesion between the bead-like spacers 24 and the alignment layer (the second alignment layer 23B) can be improved.

[0116] (Example 3 of this embodiment)

[0117] The second substrate 21B is produced by the second laminate manufacturing step SP3 described above. At this time, the diameter of the bead spacer 24 is denoted by R. In addition, the maximum diameter of the portion of the bead spacer 24 held in the protrusion 30 is denoted by r (refer to Figure 1 ), changing the ratio of r to R = r / R, and adjusting the viscosity of the coating liquid of the alignment layer 23B, etc. to produce three samples of r / R = 1.0, r / R = 0.8, and r / R = 0.6.

[0118] Air was sprayed (jet) onto one sample of Comparative Example 2 and three samples of Example 3 (Examples 3-1 to 3-3) using an air gun, and the residual rate of the bead-shaped spacer was determined. The nozzle of the air gun was 2 mm. The distance between the air gun and the second substrate was 5 mm, the spraying time was 15 sec, and the pressure of the spray was 6 kgf / cm2 The results are shown in Table 2 below.

[0119] [Table 2]

[0120]

[0121] As shown in Table 2, although the residual rate of the bead spacer in Comparative Example 2 is 20%, in any case of Examples 3-1 to 3-3, the residual rate of the bead spacer 24 is higher than that of Comparative Example 2, thereby being able to improve the residual rate of the bead spacer 24 compared with Comparative Example 2.

[0122] In Example 3, the higher the r / R is, the higher the residual rate of the bead-shaped spacer 24 is, and when r / R=1, it is 100%.

[0123] Here, in order to prevent rainbow spots from being observed in the light control film 1, the residual rate of the beaded spacers 24 is preferably 80% or more. In the above results, when r / R=0.8, the residual rate is 85%, so 0.8≤r / R is preferred.

[0124] (Comparative Example 3)

[0125] Next, Comparative Example 3 will be described. Figure 3 1 is a diagram showing the second stack 13' of Comparative Example 3. In the second orientation layer manufacturing step SP3-2, the coating agent of the second orientation layer 23B' coated on the second substrate 21B' in a manner mixed with the bead spacer 24' is dried. Here, in Comparative Example 3, a solvent with a low viscosity and a low boiling point is used. In addition, the drying wind speed is increased. As a result, although the appearance shape is different from that of the present embodiment, Figure 1 The same method is used, but a sample having a second orientation layer 23B' in which the projections 30' are hollow is produced.

[0126] Then, air was sprayed (air jet) onto the sample of Comparative Example 3 using an air gun, and the residual rate of the bead-shaped spacers was determined.

[0127] The nozzle of the air gun is 2mm The distance between the air gun and the second substrate was 5 mm, and the spraying time was 15 sec.

[0128] The jet pressure is 6kgf / cm 2 .

[0129] The results are shown in the following Table 3. In the table, the numerical values ​​of Comparative Example 2 and Example 3 described above are also shown for comparison.

[0130] [Table 3]

[0131]

[0132] As shown in Table 3, in the case of Comparative Example 3 where the convex portion 30' is hollow, the remaining rate of the beaded spacer 24' is 35%. That is, when the convex portion 30' is hollow, the adhesion between the orientation layer 23B' and the beaded spacer 24' is reduced to 35% compared with the present embodiment where the convex portion 30 is solid, which is not preferable.

[0133] That is, it is preferable that the interior of the convex portion 30 of the alignment layer 23B is filled with the material of the alignment layer 23B.

[0134] (Second embodiment)

[0135] Figure 4 It is a cross-sectional view showing a light control film 1 according to a second embodiment.

[0136] In the following description and drawings, parts having the same functions as those of the first embodiment described above are denoted by the same reference numerals at the end (last two digits), and duplicate descriptions are omitted as appropriate.

[0137] The dimming film 101 of this embodiment is as follows Figure 4 As shown in FIG. 1 , the light control film 1 of the first embodiment is mainly different from the light control film 1 of the first embodiment in that the bead-shaped spacers 124 are covered with a material forming the alignment layer.

[0138] The beaded spacers 124 of the light control film 101 of the present embodiment are held by the protrusions 130 and the cover 131 , and the protrusions 130 and the cover 131 are formed of the same alignment layer material as that of the second alignment layer 123B.

[0139] The convex portion 130 is formed in a manner to surround the outer peripheral curved surface on the lower side of the bead-shaped spacer 124 , similarly to the convex portion 30 of the first embodiment described above.

[0140] The covering portion 131 is formed to cover the entire outer peripheral curved surface (surface) of the bead spacer 124 held by the convex portion 130 , that is, is formed to cover the outer peripheral curved surface of the bead spacer 124 except for the portion held by the convex portion 130 .

[0141] The production of the second orientation layer 123B and the arrangement of the bead-like spacers 124 (formation of the protrusions 130 and the covering portions 131 ) of the present embodiment are performed, for example, as follows.

[0142] Similar to the first embodiment described above, in the second orientation layer manufacturing step (SP3-2), a coating liquid (orientation layer material) for the second orientation layer 123B in which the bead-shaped spacers 124 are dispersed is applied by a gravure coater. Then, the solvent component of the coating liquid is volatilized and dried in a drying furnace, thereby forming the second orientation layer 123B, and the bead-shaped spacers 124 are held by the protrusions 130 and the cover 131.

[0143] Here, the coating liquid of the second orientation layer 123B of this embodiment is, for example, a coating liquid with a higher viscosity than that used in the first embodiment, so that after drying, the coating liquid (orientation layer material) remains on the outer peripheral curved surface on the upper side (first substrate 21A side) of the beaded spacer 124. Thus, the second orientation layer 123B is formed on the second transparent electrode 122B, and the protrusion 130 and the cover 131 are formed so as to hold the beaded spacer 124.

[0144] The method for forming the covering portion 131 is not limited to the above, and the covering portion 131 may be formed by changing the drying conditions (drying time, drying temperature, etc.) compared to the first embodiment.

[0145] Since the convex portion 130 and the covering portion 131 of the present embodiment are formed in the same process and from the same coating liquid (alignment layer material) as described above, they are formed integrally with the second alignment layer 123B. However, the present invention is not limited thereto, and the convex portion 130 and the covering portion 131 may be formed separately. For example, as in the first embodiment, after the convex portion 130 that holds the outer peripheral curved surface of the lower side of the bead-shaped spacer 124 is formed together with the second alignment layer 123B, the covering portion 131 may be formed by another process.

[0146] In summary, the dimming film 101 of the present embodiment has a plurality of protrusions 130 protruding toward the liquid crystal layer 114 formed on the second orientation layer 123B of the second stack 113, and at least a portion of the bead spacers 124 is held by the protrusions 130. Thus, the dimming film 101, like the dimming film 1 of the first embodiment described above, can arrange the bead spacers 124 more strongly on the second orientation layer 123B, and can suppress the movement of the bead spacers during the liquid crystal inflow process as much as possible, compared with the case where the bead spacers having a fixed layer are dispersed and arranged on the orientation layer.

[0147] In addition, the dimming film 101 of this embodiment is similar to the dimming film 1 of the first embodiment described above, and since the bead spacer 124 is held by the convex portion 130 provided on the second orientation layer 123B, the gap between the second orientation layer 123B and the bead spacer 124 is filled with the orientation layer material (coating liquid). As a result, the amount of air remaining in the liquid crystal layer due to the gap can be reduced as much as possible, and the generation of bubbles in the liquid crystal layer due to heating in the lamination process (SP6) and temperature changes when the dimming film is used later can be greatly suppressed.

[0148] Furthermore, since the light control film 101 of this embodiment includes the covering portion 131 covering the outer peripheral curved surface (surface) of the bead spacer 124 held by the protrusion 130 , the bead spacer 124 can be more firmly fixed to the second alignment layer 123B than in the first embodiment.

[0149] (Deformation method)

[0150] (1) When every 1mm 2 When the number of bead spacers 24 increases, the dispersion of the bead spacers 24 in the alignment layer tends to deteriorate. This is because the bead spacers 24 aggregate and cluster. To avoid this, the bead spacers 24 may be separately fixed to the first substrate 21A and the second substrate 21B.

[0151] In this case, the density of the bead spacers 24 on one of the first substrate 21A and the second substrate 21B is lower for some reason. Usually, even if the gap of the liquid crystal layer is uneven, the occurrence of uneven gap of the liquid crystal layer can be suppressed by interpolating the bead spacers 24 on the other substrate.

[0152] Alternatively, the bead-shaped spacers may be dispersed in the coating solution of the first alignment layer so that the bead-shaped spacers are held by the protrusions formed on the first alignment layer.

[0153] (2) In addition, the process of forming the alignment layer including the bead spacers 24 on one of the first substrate 21A and the second substrate 21B may be performed in two steps. In this case, similarly to (1), the density of the bead spacers 24 fixed in the first step may be low for some reason. Usually, even if the gap of the liquid crystal layer is uneven, the occurrence of uneven gap in the liquid crystal layer can be suppressed by fixing the bead spacers 24 in the second step. Therefore, aggregation of the bead spacers 24 can be effectively avoided.

[0154] (3) Although the above-mentioned embodiment describes a flexible dimming film as one solution of the dimming component, the present invention is not limited thereto. For example, a solution in which a non-flexible plate-shaped glass plate is used as a substrate may be used as the dimming component. In this case, the dimming component may be attached to one surface of a transparent component at a location where external light from a building or a vehicle is incident, or the dimming component may be directly disposed instead of being sandwiched between two transparent components to form a laminated glass.

[0155] (Effect)

[0156] As described above, according to this embodiment, in the dimming film 1, by mixing the bead spacers 24 in the coating liquid of the alignment layer, the fixing force of the bead spacers to the alignment layer can be greatly improved compared with the case where the bead spacers are only dispersed on the alignment layer or the case where a fixing agent is used to fix the bead spacers.

[0157] [Explanation of Reference Numerals]

[0158] 1. Dimming Film

[0159] 12. First laminate

[0160] 13 Second stack

[0161] 14 Liquid crystal layer

[0162] 14A LCD

[0163] 21A 1st base material

[0164] 21B Second base material

[0165] 22A 1st transparent electrode

[0166] 22B Second transparent electrode

[0167] 23A 1st orientation layer

[0168] 23B 2nd orientation layer

[0169] 24 Spacer

[0170] 24 Bead spacers

[0171] 25 Sealant

[0172] 30 convex part

Claims

1. A dimming component, characterized in that: include: A first laminate comprising a substrate and an orientation layer, a second stacked body including a substrate and an alignment layer, and arranged relative to the first stacked body so that the alignment layers face each other; a liquid crystal layer disposed between the first stack and the second stack, wherein the liquid crystal layer has its orientation controlled by driving an electrode provided on at least one of the first stack and the second stack, and A plurality of bead-shaped spacers, which are arranged in the liquid crystal layer; A plurality of protrusions protruding toward the liquid crystal layer are formed on at least one of the orientation layer of the first stack and the orientation layer of the second stack; At least a portion of the bead-shaped spacer is held by the protrusion. Among the plurality of bead-shaped spacers arranged in the liquid crystal layer, an aggregation ratio of the bead-shaped spacers aggregated in a number of 2 to 4 is 20% to 80%.

2. The dimming component according to claim 1, characterized in that: The alignment layer includes a covering portion that covers a surface of the bead-shaped spacer held by the convex portion.

3. The dimming component according to claim 1 or 2, characterized in that: Each substrate of the first laminate and the second laminate is a resin film; The liquid crystal layer contains a dichroic dye.

4. The dimming component according to claim 1 or 2, characterized in that: A hard coat layer is provided on a surface of at least one of the substrates of the first stack and the second stack on the liquid crystal layer side.

5. The dimming component according to claim 1 or 2, characterized in that: The bead-like spacer is spherical; When the diameter of the bead-shaped spacer is represented by R and the maximum diameter of the portion of the bead-shaped spacer held in the protrusion is represented by r, 0.8≤r / R.

6. The dimming component according to claim 1 or 2, characterized in that: The interior of the protrusion is filled with the material of the alignment layer.

7. A method for manufacturing a dimming component, characterized in that: The manufacturing process of the dimming component includes: a first stacked body manufacturing step of forming an orientation layer on a first substrate to produce a first stacked body, a second stack manufacturing step of forming an orientation layer on a second substrate to manufacture a second stack, a sealing portion forming step of forming a sealing portion on the outer periphery of the second stacked body, a liquid crystal inflow step of causing the liquid crystal to flow into the interior of the sealing portion to form a liquid crystal layer, and a lamination step of laminating the first laminate and the second laminate; In the manufacturing process of the light-adjusting member, at least one of the material forming the alignment layer of the first substrate and the material forming the alignment layer of the second substrate includes a bead-shaped spacer, Among the plurality of bead-shaped spacers arranged in the liquid crystal layer, an aggregation ratio of the bead-shaped spacers aggregated in a number of 2 to 4 is 20% to 80%.

8. The method for manufacturing a light-adjusting component according to claim 7, wherein: Both of the materials forming the alignment layer of the first substrate and the materials forming the alignment layer of the second substrate contain bead-shaped spacers.

9. The method for manufacturing a light-adjusting component according to claim 7 or 8, characterized in that: The stacked body manufacturing step of forming an alignment layer with a material including the bead-shaped spacers in the first stacked body manufacturing step and the second stacked body manufacturing step includes the step of forming the alignment layer twice.

10. A dimming body, comprising: Transparent components, and The light control member according to any one of claims 1 to 6, arranged on the transparent member.

11. A vehicle, wherein: The light control member according to any one of claims 1 to 6 is arranged at a location where external light is incident.

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