Light control film and laminated glass

Abstract

The present invention relates to a light control film and laminated glass. A light control film (10) is provided with a laminate (25) and at least one seal member (30). The laminate is provided with: an active layer (253); a first substrate (251) and a second substrate (255) provided so as to sandwich the active layer; a first conductive layer (252) disposed on the face of the first substrate facing the active layer; and a second conductive layer (254) disposed on the face of the second substrate facing the active layer, wherein the seal member is attached so as to surround and seal the side edges of the laminate in a cross-sectional view of the laminate, the seal member is provided with at least one adhesive region (R1) and at least one non-adhesive region (R2) on the face facing the laminate, and the at least one adhesive region is disposed so as to face the active layer. This structure makes it possible to prevent low molecular components in the intermediate film from entering the liquid crystal layer of a PDLC film through the adhesive, thereby preventing the edges of the PDLC film from becoming transparent.

Description

Light control film and laminated glass

[0001] The present invention relates to a light control film and laminated glass.

[0002] Laminated glass is sometimes used for window panes in automobiles and railways. Such laminated glass may have various functions, for example, by encapsulating a functional film. An example of a functional film is a film-like light-control element (light-control film) whose visible light transmittance, etc., changes when a voltage is applied. A light-control film has a structure in which a light-control layer is sandwiched between two substrates. The light-control layer may be, for example, one or more selected from the group consisting of a suspended particle device (SPD), a polymer-dispersed liquid crystal (PDLC), a polymer network liquid crystal (PNLC), a guest-host liquid crystal, and an electrochromic material.

[0003] It has been found that light-control films with a PDLC light-control layer undergo a heat resistance test, resulting in the edges of the PDLC film becoming transparent. This can cause the film to fail to meet the standards required for use in automobiles and railways, and can also place restrictions on glass design. This type of deterioration (edge ​​transparency) occurs gradually not only during heat resistance tests, but also during actual use. This type of deterioration can occur regardless of the type of PDLC.

[0004] One possible reason why the edges of the PDLC film become transparent is that, for example, when the cross section of the PDLC comes into contact with the interlayer, the liquid crystal component and the low-molecular-weight component in the interlayer migrate to each other, causing the migrated area to appear transparent.

[0005] To prevent PDLC from becoming transparent, it is necessary to create a structure that prevents the liquid crystal component from migrating from the cross section of the PDLC and prevents other components from penetrating from the outside. Furthermore, if the edges of the PDLC film are sealed with a tape-like sealing material with adhesive on one side, there is a problem that low-molecular-weight components can penetrate through the adhesive layer.

[0006] As a solution to this problem, the following structure is known: a functional film assembly including a functional film having at least one active layer laminated between first and second planar electrode layers, at least a portion of an edge region of the functional film being sealed by a sealing member, the sealing member comprising a strip of polymer film material having on one side a first band of adhesive material adjacent to a first edge of the strip of polymer film material and a second band of adhesive material adjacent to a second edge of the strip of polymer film material, with an adhesive-free region between the first band of adhesive material and the second band of adhesive material, the adhesive-free region being located in a position coinciding with the active layer of the functional film.

[0007] Such a sealing member prevents the active layer (liquid crystal layer) from coming into contact with the adhesive, preventing the penetration of components from the adhesive interlayer. However, this structure not only causes problems with appearance, but also increases the risk of foaming in the interlayer. While the penetration of components from the adhesive interlayer can be prevented without using any adhesive, there are concerns about the sealing member becoming misaligned and the likelihood of gaps forming between the sealing member and the laminate, which can lead to foaming.

[0008] Chinese Patent No. 102067032

[0009] The present invention has been made in view of the above points, and aims to provide a light control film and laminated glass that can suppress the edge of the light control film from becoming transparent and also suppress interlayer foaming.

[0010] One disclosed embodiment of the light-controlling film 10 comprises a laminate 25 and at least one sealing member 30, the laminate comprising an active layer 253, a first substrate 251 and a second substrate 255 arranged to sandwich the active layer, a first conductive layer 252 arranged on the surface of the first substrate facing the active layer, and a second conductive layer 254 arranged on the surface of the second substrate facing the active layer, the sealing member being attached so as to surround and seal the side edges of the laminate in a cross-sectional view, the sealing member having at least one adhesive region R1 and at least one non-adhesive region R2 on the surface facing the laminate, and at least one of the adhesive regions being arranged to face the active layer.

[0011] According to one embodiment of the disclosure, it is possible to prevent low molecular weight components in the interlayer from penetrating into the liquid crystal layer of the PDLC film via the adhesive, and to prevent the edges of the PDLC film from becoming transparent.

[0012] 1B is a schematic diagram showing the structure of laminated glass with a light control film installed, and is a top view. A cross-sectional view taken along line IB-IB in FIG. 1A. A cross-sectional view showing the structure of a light control film laminate. A partial cross-sectional view showing the light control film of the first embodiment. A cross-sectional view showing the light control film of modified example 1 of the first embodiment. A cross-sectional view showing the light control film of modified example 2 of the first embodiment. A cross-sectional view showing the light control film of modified example 3 of the first embodiment. A cross-sectional view showing the light control film of modified example 4 of the first embodiment. A cross-sectional view showing the light control film of modified example 5 of the first embodiment. A cross-sectional view showing the light control film of modified example 6 of the first embodiment. A cross-sectional view showing the light control film of modified example 7 of the first embodiment. A cross-sectional view showing the light control film of the second embodiment. A cross-sectional view showing the light control film of the third embodiment. A schematic diagram showing the structure of the light control film of the fourth embodiment, and is a top view. A cross-sectional view taken along line XIIIB-XIIIB in FIG. 13A. A cross-sectional view showing the structure of the light control film of the fourth embodiment. A cross-sectional view showing the structure of the light control film of modified example 1 of the fourth embodiment. A cross-sectional view showing the structure of the light control film of modified example 2 of the fourth embodiment. 1 is a schematic diagram showing how a sealing member is attached to a laminated body.

[0013] Hereinafter, the embodiments of the present invention will be described with reference to the drawings. In each drawing, the same components are designated by the same reference numerals, and duplicate explanations may be omitted. In each drawing, the size and shape may be partially exaggerated to make the contents of the present invention easier to understand.

[0014] Note that, although a roof glass for a vehicle will be described as an example, the present invention is not limited to this, and the glass according to the embodiment can be applied to, in addition to a roof glass for a vehicle, for example, a windshield, a rear glass, a side glass, etc. Furthermore, a vehicle is typically an automobile, but refers to any moving body having glass, including a train, a ship, an airplane, etc.

[0015] In addition, the plan view refers to a predetermined area of ​​the roof glass viewed from the normal direction of the predetermined area, and the planar shape refers to the shape of the predetermined area of ​​the roof glass viewed from the normal direction of the predetermined area. In the plan view, the inside of the laminated glass refers to the direction toward the center of the laminated glass.

[0016] <First embodiment> Figures 1A and 1B are schematic diagrams showing the structure of laminated glass with a light control film installed. Figure 1A is a top view, and Figure 1B is a cross-sectional view taken along the line IB-IB of Figure 1A. Figure 2 is a cross-sectional view showing the structure of a laminate of light control films. Figure 3 is a partial cross-sectional view showing the light control film of the first embodiment. Here, in a plan view, the longitudinal direction of the laminated glass 20 is the X direction, the lateral direction is the Y direction, and the thickness direction is the Z direction.

[0017] As shown in Fig. 1, the laminated glass 20 includes a first glass sheet 21 that is the vehicle exterior glass sheet, a second glass sheet 22 that is the vehicle interior glass sheet, an interlayer film 23, a shielding layer 24, and a light control film 10. The interlayer film 23 may consist of one layer, or may consist of two or more layers.

[0018] The first glass sheet 21 is an exterior glass sheet that faces the exterior side of the vehicle when the laminated glass 20 is installed in the vehicle. The second glass sheet 22 is an interior glass sheet that faces the interior side of the vehicle when the laminated glass 20 is installed in the vehicle. For example, the first glass sheet 21 and the second glass sheet 22 have a predetermined curvature.

[0019] The first glass plate 21 and the second glass plate 22 are a pair of glass plates facing each other, and the interlayer film 23 and the light control film 10 are positioned between the pair of glass plates. The first glass plate 21 and the second glass plate 22 are fixed together with the interlayer film 23 and the light control film 10 sandwiched between them. Details of the first glass plate 21, the second glass plate 22, and the interlayer film 23 will be described later.

[0020] The shielding layer 24 is an opaque (e.g., black) colored ceramic layer and can be provided, for example, in a strip shape along the peripheral edge of the laminated glass 20. In the example of Fig. 1 , the shielding layer 24 is provided on both the interior side of the first glass sheet 21 and the interior side of the second glass sheet 22. However, the shielding layer 24 may be provided on only one of the interior side of the first glass sheet 21 and the interior side of the second glass sheet 22, as necessary.

[0021] The presence of the opaque shielding layer 24 at the peripheral edge of the laminated glass 20 can suppress ultraviolet degradation of resins such as urethane that hold the peripheral edge of the laminated glass 20 to the vehicle body. In addition, the electrodes and electrode lead wires electrically connected to the light control film 10 can be concealed so that they are difficult to see from both the outside and inside of the vehicle.

[0022] The shielding layer 24 can be formed, for example, by applying a ceramic color paste made of a molten glass material containing a black pigment to a glass plate by screen printing or the like, and then firing the paste, but is not limited to this. Alternatively, the shielding layer 24 can be formed, for example, by applying an organic ink containing a black or dark pigment to a glass plate by screen printing or the like, and then drying the ink.

[0023] The light control film 10 is an element that can switch the light transmittance of the laminated glass 20. The light control film 10 may be disposed over almost the entire laminated glass 20, or may be disposed over only a portion of the laminated glass 20, as necessary. The planar shape of the light control film 10 is, for example, a rectangle that is smaller than the planar shape of the laminated glass 20. In the example of Figure 1, the outer edge of the light control film 10 is positioned so as to overlap with the shielding layer 24 in a planar view.

[0024] Fig. 2 is a cross-sectional view showing the structure of a light control film laminate. As shown in Fig. 2, the light control film laminate 25 includes a first substrate 251, a first conductive layer 252, a light control layer 253 as an active layer, a second conductive layer 254, and a second substrate 255, and is encapsulated in an intermediate film 23, i.e., is covered by the intermediate film 23. The thickness of the laminate 25 is, for example, 0.1 mm to 0.8 mm, and preferably 0.1 mm to 0.5 mm.

[0025] The first base material 251 and the second base material 255 are transparent resin layers. The thickness of the first base material 251 and the second base material 255 is, for example, 5 μm or more and 500 μm or less, preferably 10 μm or more and 200 μm or less, and more preferably 50 μm or more and 150 μm or less.

[0026] The first substrate 251 and the second substrate 255 can be formed from any material selected from the group consisting of, for example, polyethylene terephthalate, polyethylene naphthalate, polyamide, polyether, polysulfone, polyethersulfone, polycarbonate, polyarylate, polyetherimide, polyetheretherketone, polyimide, aramid, polybutylene terephthalate, triacetyl cellulose, polyurethane, and cycloolefin polymer.

[0027] The first conductive layer 252 is formed on the surface of the first substrate 251 facing the second glass plate 22, and is in contact with the surface of the light control layer 253 facing the first glass plate 21. The second conductive layer 254 is formed on the surface of the second substrate 255 facing the first glass plate 21, and is in contact with the surface of the light control layer 253 facing the second glass plate 22. In other words, the first conductive layer 252 and the second conductive layer 254 are a pair of conductive thin films that sandwich the light control layer 253.

[0028] The first conductive layer 252 and the second conductive layer 254 may be made of, for example, a transparent conductive oxide (TCO), such as, but not limited to, tin-doped indium oxide (ITO), aluminum-doped zinc oxide (AZO), and indium-doped cadmium oxide.

[0029] Transparent conductive polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) or poly(4,4-dioctylcyclopentadithiophene) can also be suitably used for the first conductive layer 252 and the second conductive layer 254. Furthermore, a laminated film of a metal layer and a dielectric layer, silver nanowires, a metal mesh of silver or copper, or the like can also be suitably used for the first conductive layer 252 and the second conductive layer 254.

[0030] The first conductive layer 252 and the second conductive layer 254 can be formed by using a physical vapor deposition (PVD) method such as a sputtering method, a vacuum deposition method, an ion plating method, etc. The first conductive layer 252 and the second conductive layer 254 may also be formed by a chemical vapor deposition (CVD) method or a wet coating method.

[0031] The light control layer 253 is sandwiched between a first substrate 251 on which a first conductive layer 252 is formed and a second substrate 255 on which a second conductive layer 254 is formed. A polymer dispersed liquid crystal (PDLC), which is a type of liquid crystal layer, is used as the light control layer 253. PDLC contains a liquid crystal material and a polymer material that forms a network structure that can control the movement of the liquid crystal material, and can be produced using known materials and methods disclosed in, for example, U.S. Patent Publications US4834509A, US4688900A, and US5304323A.

[0032] The operating principle of the light-controlling layer 253 includes the following: When no electric field is applied, the liquid crystal droplets can be randomly distributed in the polymer material with their directors freely oriented. In such a case, the refractive index of the liquid crystal for normal light does not match that of the polymer material, causing a relatively strong scattering effect on light, resulting in a translucent or opaque "milky" appearance for the PDLC film. Under an electric field, the liquid crystal droplets can align their directors along the direction of the external electric field due to their positive dielectric anisotropy. When the refractive index of the liquid crystal for normal light matches that of the polymer material, light can pass through the PDLC film, resulting in a transparent appearance for the PDLC film. Specifically, the higher the voltage applied to the PDLC film, the more transparent the PDLC film becomes. The thickness of the PDLC film is not particularly limited, but is preferably between 0.1 mm and 0.8 mm inclusive from the standpoints of ease of handling and availability.

[0033] The light control film 10 further includes a pair of light control bus bars (not shown). The pair of light control bus bars are arranged, for example, at positions overlapping the shielding layer 24 in a planar view. One of the pair of light control bus bars is electrically connected to the first conductive layer 252, and the other is electrically connected to the second conductive layer 254. Electricity is passed through the first conductive layer 252 and the second conductive layer 254 to drive the light control layer 253. One electrode of the pair of light control bus bars is, for example, a positive electrode and is connected to the positive side of a power source, such as a battery, mounted on the vehicle via a lead wire or the like. The other electrode of the pair of light control bus bars is, for example, a negative electrode and is connected to the negative side of a power source, such as a battery, mounted on the vehicle via a lead wire or the like. When voltage is supplied to the light control layer 253 from a power source, such as a battery, via the pair of light control bus bars, the transmittance of the light control layer 253 changes depending on the voltage. Silver paste is preferably used as the light control bus bars. The silver paste can be applied by a printing method such as screen printing or by hand. Alternatively, a copper ribbon, a flat-braided copper wire, or a copper tape with a conductive adhesive may be used as the dimming bus bar.

[0034] The light control film 10 may have multiple regions where the transmittance changes, for example, by providing an insulating region in at least one of the first conductive layer 252 and the second conductive layer 254. The light control film 10 may also have three or more light control bus bars.

[0035] The light control film 10 further includes a sealing member 30. This sealing member 30 is constructed by providing an adhesive layer on a strip-shaped base material. The sealing member 30 is also constructed so that after the adhesive layer is provided, the inner surface 31 of the sealing member 30 facing the laminate 25 is flush with the laminate 25. By configuring it in this way, the laminate 25 can be properly sealed when the sealing member 30 is attached to the laminate 25.

[0036] The sealing member 30 can be provided at any location around the laminate 25 as needed. Fig. 3 illustrates only the case where the sealing member 30 is provided on one side of the laminate 25 in the X direction. At least one adhesive region R1 and at least one non-adhesive region R2 are provided on the inner surface 31 of the sealing member 30 facing the laminate 25. Fig. 3 illustrates a structure having one adhesive region R1 and two non-adhesive regions R2.

[0037] The adhesive region R1 is provided with adhesive, and the non-adhesive region R2 is not provided with adhesive.

[0038] 3, in the first embodiment, one adhesive region R1 is provided in the central portion of the inner surface 31 of the sealing member 30 that faces the laminate 25, and non-adhesive regions R2 are provided at both end portions of the inner surface 31. In addition, the adhesive region R1 is provided so as to cover the entire side surface of the laminate 25 and parts of the upper and lower surfaces of the laminate 25 when the sealing member 30 is attached to the laminate 25.

[0039] By making both end portions of the inner surface 31 non-adhesive regions R2, it is possible to prevent low-molecular-weight components in the interlayer from penetrating into the liquid crystal layer of the PDLC film via the adhesive, and to prevent the edges of the PDLC film from becoming transparent. Furthermore, the provision of the non-adhesive regions R2 allows air to escape from the non-adhesive regions R2 during the production of laminated glass with the light control film installed, thereby suppressing interlayer foaming.

[0040] When attaching the sealing member 30, the adhesive region R1 is aligned with the center position of the side surface of the laminate 25 and adhered thereto. The sealing member 30 is then folded along the edge of the laminate 25. In the corner regions of the laminate 25 in a top view, the sealing members 30 adhered along the short-side direction of the laminate 25 may overlap with the sealing members 30 adhered along the long-side direction of the laminate 25. As long as the orthogonal sealing members 30 overlap each other, the sealing members 30 may or may not protrude from the corner regions. Furthermore, the overlapping portions are not limited to corner regions, and may also be part of the long-side direction or part of the short-side direction of the laminate 25.

[0041] This prevents the seal member 30 from shifting position, achieving stronger sealing. In addition, since both end portions of the inner surface 31 are non-adhesive regions R2, the risk of bubbles forming in the overlapping areas can be reduced.

[0042] <Modification 1 of First Embodiment> FIG. 4 is a cross-sectional view showing a light control film according to Modification 1 of the first embodiment.

[0043] In this modified example 1, the adhesive region R1 is provided so as to cover only the entire side surface of the laminate 25 when attached to the laminate 25. In other words, when attached to the laminate 25, the adhesive region R1 does not extend to the top and bottom surfaces of the laminate 25.

[0044] According to this modification 1, the same effects as those of the first embodiment can be obtained. Furthermore, the non-adhesive region can be set as long as possible. This further prevents low-molecular-weight components in the interlayer from penetrating into the liquid crystal layer of the PDLC film via the adhesive, preventing the edges of the PDLC film from becoming transparent. Furthermore, the effect of suppressing foaming can be achieved.

[0045] <Modification 2 of First Embodiment> FIG. 5 is a cross-sectional view showing a light control film according to Modification 2 of the first embodiment.

[0046] In this second modification, multiple adhesive regions R1 are provided at intervals across the entire inner surface of the seal member 30. At least one adhesive region R1 is provided in a position facing the middle of the side surface of the light-control layer 253. In addition, one adhesive region R1 is provided at each of the two ends of the seal member 30.

[0047] According to this modification 2, it is possible to minimize the influence of the adhesive in the adhesive region R1 on the light control layer 253, which is the active layer. It is also possible to prevent low-molecular components in the interlayer from penetrating into the liquid crystal layer of the PDLC film via the adhesive, and to prevent the edges of the PDLC film from becoming transparent.

[0048] <Modification 3 of First Embodiment> FIG. 6 is a cross-sectional view showing a light control film according to Modification 3 of the first embodiment.

[0049] In this variant example 3, the first substrate 251 and the second substrate 255 of the laminate 25 are arranged offset in the Z direction, i.e., the first substrate 251 and the second substrate 255 are not configured to be completely opposite each other in the Z direction.

[0050] At one end of the laminate 25 in the X direction, an adhesive region R1 is provided on the inner surface 31 of the seal member 30 at a position facing the side surface of the first base material 251 and the side surface of the light-controlling layer 253, and the remaining portion of the inner surface 31 of the seal member 30 is a non-adhesive region R2. At the other end of the laminate 25 in the X direction, the adhesive region R1 is provided only on the inner surface 31 of the seal member 30 at a position facing the side surface of the second base material 255 and the side surface of the light-controlling layer 253, and the remaining portion of the inner surface 31 of the seal member 30 is a non-adhesive region R2.

[0051] According to this modification 3, the non-adhesive region R2 can be made as large as possible. As in the first embodiment, it is possible to prevent low-molecular-weight components in the interlayer from penetrating into the liquid crystal layer of the PDLC film via the adhesive, thereby preventing the edges of the PDLC film from becoming transparent. This also achieves the effect of suppressing foaming.

[0052] <Modification 4 of First Embodiment> FIG. 7 is a cross-sectional view showing a light control film according to Modification 4 of the first embodiment.

[0053] In this variant example 4, as in variant example 3, the first substrate 251 and the second substrate 255 of the laminate 25 are arranged offset in the Z direction, i.e., the first substrate 251 and the second substrate 255 are not configured to be completely opposite each other in the Z direction.

[0054] At one end of the laminate 25 in the X direction, adhesive regions R1 are provided on the inner surface 31 of the seal member 30 at positions facing the side surface of the first substrate 251, the side surface of the light-controlling layer 253, the upper surface of the second substrate 255 exposed from the light-controlling layer 253, and part of the upper surface of the first substrate 251, with non-adhesive regions R2 being the remaining part of the inner surface 31 of the seal member 30. At the other end of the laminate 25 in the X direction, adhesive regions R1 are provided only on the inner surface 31 of the seal member 30 at positions facing the side surface of the second substrate 255, the side surface of the light-controlling layer 253, the lower surface of the first substrate 251 exposed from the light-controlling layer 253, and part of the lower surface of the second substrate 255, with the remaining part of the inner surface 31 of the seal member 30 being the non-adhesive region R2.

[0055] The arrangement of the seal member 30 in the Y direction is the same as the arrangement in the X direction, and therefore a detailed description thereof will be omitted here.

[0056] According to this fourth modification, as in the first embodiment, it is possible to prevent low-molecular-weight components in the interlayer from penetrating into the liquid crystal layer of the PDLC film via the adhesive, thereby preventing the edges of the PDLC film from becoming transparent, while also achieving the effect of suppressing foaming.

[0057] <Fifth Modification of First Embodiment> FIG. 8 is a cross-sectional view showing a light control film according to a fifth modification of the first embodiment.

[0058] Compared to variant 3, variant 5 changes the structure of the sealing member 30 at one end of the laminate 25 in the X direction, while the structure of the sealing member 30 at the other end of the laminate 25 in the X direction is the same as variant 3.

[0059] 8 , the sealing member 30 has a plurality of adhesive regions R1 (three are shown here as an example) at one end in the X direction of the laminate 25. One adhesive region R1 is provided on the inner surface 31 of the sealing member 30 at a position facing the side surface of the first base material 251, the side surface of the light-controlling layer 253, the upper surface of the second base material 255 exposed from the light-controlling layer 253, and the side surface of the second base material 255. One adhesive region R1 is provided at each end portion of the inner surface 31 of the sealing member 30. The remaining portions of the inner surface 31 of the sealing member 30 are non-adhesive regions R2.

[0060] According to this modification 5, the non-adhesive region R2 can be made as large as possible at the other end of the laminate 25 in the X direction, as in modification 3. Also, as in the first embodiment, low-molecular-weight components in the interlayer film can be prevented from penetrating into the liquid crystal layer of the PDLC film via the adhesive, preventing the edges of the PDLC film from becoming transparent. By providing a larger adhesive region R1 at one end of the laminate 25 in the X direction, the seal member 30 can be firmly attached to the laminate 25.

[0061] <Sixth Modification of First Embodiment> FIG. 9 is a cross-sectional view showing a light control film according to a sixth modification of the first embodiment.

[0062] In this sixth modification, the first base material 251 and the second base material 255 of the laminate 25 are arranged to be shifted in the Z direction.

[0063] At one end of the laminate 25 in the X direction, an adhesive region R1 is provided on the inner surface 31 of the seal member 30 at a position facing the side of the first substrate 251, the side of the light-adjusting layer 253, the upper surface of the second substrate 255 exposed from the light-adjusting layer 253, the side of the second substrate 255, a part of the upper surface of the first substrate 251, and a part of the lower surface of the second substrate 255, and the remaining part of the inner surface 31 of the seal member 30 is a non-adhesive region R2. At the other end of the laminate 25 in the X direction, the adhesive region R1 is provided on the inner surface 31 of the seal member 30 at a position facing the side of the second substrate 255, the side of the light-adjusting layer 253, the lower surface of the first substrate 251 exposed from the light-adjusting layer 253, the side of the first substrate 251, a part of the upper surface of the first substrate 251, and a part of the lower surface of the second substrate 255, and the remaining part of the inner surface 31 of the seal member 30 is a non-adhesive region R2.

[0064] According to this sixth modification, as in the first embodiment, it is possible to prevent low-molecular-weight components in the interlayer from penetrating into the liquid crystal layer of the PDLC film via the adhesive, thereby preventing the edges of the PDLC film from becoming transparent, while also achieving the effect of suppressing foaming.

[0065] <Seventh Modification of First Embodiment> FIG. 10 is a cross-sectional view showing a light control film according to a seventh modification of the first embodiment.

[0066] In this seventh modification, both end portions of the seal member 30 are shifted in the Z direction in comparison with the sixth modification.

[0067] According to this modification 7, the non-adhesive regions at both ends of the sealing member 30 can be made larger than those of modification 6, and low-molecular-weight components in the interlayer film can be prevented from penetrating into the liquid crystal layer of the PDLC film via the adhesive, preventing the edges of the PDLC film from becoming transparent. This also achieves the effect of suppressing foaming.

[0068] Second Embodiment Next, a light control film according to a second embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is a cross-sectional view showing the light control film of the second embodiment.

[0069] In the second embodiment, the structures of the first substrate 251, the first conductive layer 252, the light control layer 253, the second conductive layer 254, and the second substrate 255 of the laminate are the same as those of the first embodiment, and therefore detailed description thereof will be omitted here. The difference between the second embodiment and the first embodiment is the structure of the seal member 30, and the structure of the seal member 30 will be described in detail below.

[0070] 11 , an adhesive region R1 is provided over the entire inner surface 31 of the seal member 30. In addition, non-adhesive members 40 are disposed on both ends of the seal member 30. One end of the non-adhesive member 40 is sandwiched between the adhesive region R1 at the end of the seal member 30 and the base material of the laminate 25, and the other end is provided so as to cover the outer surface of the seal member 30.

[0071] Furthermore, sandwiching the non-adhesive member 40 between the adhesive region R1 at the end of the seal member 30 and the substrate of the laminate 25 is equivalent to forming a non-adhesive region with the non-adhesive member 40. As a result, similar to the first embodiment, it is possible to prevent low-molecular-weight components in the interlayer film from penetrating into the liquid crystal layer of the PDLC film via the adhesive, and to prevent the edges of the PDLC film from becoming transparent. This also achieves the effect of suppressing foaming.

[0072] Third Embodiment Next, a light control film according to a third embodiment of the present invention will be described with reference to Fig. 12. Fig. 12 is a cross-sectional view showing the light control film of the third embodiment.

[0073] In the third embodiment, the structures of the first substrate 251, the first conductive layer 252, the light control layer 253, the second conductive layer 254, and the second substrate 255 of the laminate are the same as those of the first embodiment, and therefore detailed description thereof will be omitted here. The difference between the second embodiment and the first embodiment is the structure of the seal member 30, and the structure of the seal member 30 will be described in detail below.

[0074] 12, the seal member 30 is composed of a first seal member 301 and a second seal member 302. The first seal member 301 and the second seal member 302 have a vertically symmetrical structure, and here, an explanation of the second seal member 302 will be omitted and only the first seal member 301 will be explained.

[0075] The first seal member 301 has an adhesive region R1 approximately in the middle of its inner surface, and non-adhesive regions R2 at both ends. The first seal member 301 and the second seal member 302 overlap in the Z direction so as to sandwich the edge of the laminate 25. In the overlapping state, a portion of the adhesive region R1 of the first seal member 301 overlaps a portion of the adhesive region R1 of the second seal member 302, and other portions of the adhesive region R1 of the first seal member 301 are arranged to cover the side surfaces of the first base material 251, the side surfaces of the light-controlling layer 253, and the top surface of the first base material 251. In the overlapping state, a portion of the adhesive region R1 of the second seal member 302 overlaps a portion of the adhesive region R1 of the first seal member 301, and other portions of the adhesive region R1 of the second seal member 302 are arranged to cover the side surfaces of the second base material 255, the side surfaces of the light-controlling layer 253, and the top surface of the second base material 255.

[0076] According to this third embodiment, the seal member 30 is formed by overlapping the first seal member 301 and the second seal member 302 along the Z direction, and can be properly attached even when the edge of the laminate 25 is curved along the XY plane. Furthermore, according to this third embodiment, the non-adhesive regions R2 provided at both ends of the first seal member 301 and the second seal member 302 can remove air from the overlapping portion, thereby suppressing interlayer foaming. This can also achieve the effect of preventing the edge of the light control film from becoming transparent.

[0077] <Fourth embodiment> Next, a light control film according to a fourth embodiment of the present invention will be described with reference to Figures 13A, 13B, and 14. Figures 13A and 13B are schematic diagrams showing the structure of the light control film of the fourth embodiment. Figure 13A is a top view, and Figure 13B is a cross-sectional view taken along line XIIIB-XIIIB of Figure 13A. Figure 14 is a cross-sectional view showing the structure of the light control film of the fourth embodiment.

[0078] 13A and 13B, the sealing member is not shown, but as shown in Figures 13A and 13B, at least one of the first conductive layer 252 and the second conductive layer 254 of the laminate is connected to the electrode 50. In this case, it is possible for low-molecular-weight components in the interlayer film to penetrate into the light-controlling layer 253 through the connection portion of the electrode 50.

[0079] 14 , in this embodiment, the sealing member 30 provided at the end of the laminate 25 on the electrode 50 side includes a first sealing member 301 and a second sealing member 302. As in the third embodiment, the first sealing member 301 and the second sealing member 302 have a vertically symmetrical structure, and here, only the first sealing member 301 will be described, and a description of the second sealing member 302 will be omitted.

[0080] The first seal member 301 has an adhesive region R1 provided in the approximate middle of its inner surface, and non-adhesive regions R2 at both ends.

[0081] The first sealing member 301 and the second sealing member 302 overlap in the Z direction so as to sandwich the laminate 25 and the electrode 50. In the overlapping state, the adhesive region R1 of the first sealing member 301 covers a part of the upper surface of the first base material 251, the side surface of the first base material 251, and the upper surface of the electrode 50, and the adhesive region R1 of the second sealing member 302 covers a part of the lower surface of the second base material 255, the side surface of the second base material 255, and the lower surface of the electrode 50.

[0082] According to the fourth embodiment, the connection portion of the electrode 50 to at least one of the first conductive layer 252 and the second conductive layer 254 is sealed by the adhesive region R1 of each of the first sealing member 301 and the second sealing member 302. This can prevent low-molecular-weight components in the interlayer film from penetrating into the photochromic layer through the connection portion of the electrode. This also achieves the effect of suppressing foaming.

[0083] <Modification 1 of Fourth Embodiment> FIG. 15 is a cross-sectional view showing the structure of a light control film according to Modification 1 of the fourth embodiment.

[0084] In this modification 1, the ends of the switchable layer 253 and the second base material 255 on the electrode 50 side are flush with each other, whereas the end of the first base material 251 (and the first conductive layer 252) on the electrode 50 side protrudes a certain length from the switchable layer 253. In this case, low-molecular-weight components in the interlayer film are more likely to penetrate into the switchable layer 253 through the underside of the electrode 50.

[0085] Therefore, in this modification 1, the seal member 30 has an adhesive region R1 in the approximate middle of its inner surface and non-adhesive regions R2 at both end portions. The adhesive region R1 covers a part of the lower surface of the second base material 255, the side surfaces of the second base material 255, the side surfaces of the light-controlling layer 253, and the lower surface of the electrode 50.

[0086] This modification 1 also makes it possible to prevent low-molecular components in the interlayer from penetrating into the light-controlling layer via the electrodes, while also achieving the effect of suppressing foaming.

[0087] <Modification 2 of Fourth Embodiment> FIG. 16 is a cross-sectional view showing the structure of a light control film according to Modification 2 of the fourth embodiment.

[0088] In this modification 2, the edges of the switchable layer 253 and the second substrate 255 on the electrode 50 side are flush with each other, whereas the edges of the first substrate 251 (and the first conductive layer 252) on the electrode 50 side protrude from the switchable layer 253 and extend so as to be aligned with the edges of the electrode 50. In this case, since the electrode 50 is short, the low-molecular-weight components in the intermediate film can more easily penetrate into the switchable layer 253 via the underside of the electrode 50.

[0089] For this reason, in the present modified example 2, the sealing member 30 is provided so that the adhesive region R1 covers part of the lower surface of the second base material 255, the side surfaces of the second base material 255, the side surfaces of the light-controlling layer 253, and the entire lower surface of the electrode 50. The non-adhesive region R2 of the sealing member 30 covers the lower surface of the second base material 255.

[0090] This modification 2 also makes it possible to prevent low-molecular components in the interlayer from penetrating into the light-controlling layer via the electrodes, while also achieving the effect of suppressing foaming.

[0091] As a result of their research, the inventors of the present application have found that a ratio of adhesive region R1 to non-adhesive region R2 of the sealing member of 2:8 to 8:2, preferably 3:7 to 8:2, and more preferably 4:6 to 8:2, is appropriate from the standpoint of achieving both accuracy in application and the effect of suppressing edge transparency.

[0092] (Production of light-controlling film) A sealing member with a total thickness of approximately 53 μm and a width of 10 mm was prepared, which consisted of an approximately 25 μm thick polyester substrate with an approximately 28 μm thick acrylic adhesive applied to one side. The adhesive was partially removed from this sealing member, leaving one adhesive region R1 in the center and two non-adhesive regions R2 at both ends. Note that the width of the adhesive region R1 and the width of the two non-adhesive regions R2 were varied as shown in Table 1, and four sealing members were obtained.

[0093]

[0094] Then, the four obtained sealing members were placed on the four sides of the laminate in which the active layer was sandwiched between two substrates with conductive layers, with the adhesive region R1 facing the active layer, and attached as shown in Figure 17 to obtain a light-control film with sealing members.

[0095] (Evaluation of Deterioration Width) A laminated glass plate was prepared by laminating a 2 mm thick glass plate, a 0.38 mm thick interlayer film, a light control film with a sealing member, a 0.38 mm thick interlayer film, and a 2 mm thick glass plate in this order. The laminated glass plate was then placed in a resin bag, the inside of the bag was evacuated, and the bag was then left at a temperature of 120°C for 30 minutes. The glass was then heated and pressurized in an autoclave at a temperature of 110°C and a pressure of 1.3 MPa to obtain a laminated glass. The obtained laminated glass was left at a temperature of 100°C for a maximum of approximately 500 hours, and the deterioration width from the edge of the PDLC light control film was measured.

[0096] As a result, as shown in Figure 18, in the area where sealing member 4, which did not have a non-adhesive region R2, was attached, the longer the storage time, the greater the deterioration width, exceeding 10 mm after approximately 500 hours of storage. On the other hand, in sealing members 1 to 3, which had two non-adhesive regions R2, the deterioration width was kept at a constant level even when the storage time was long, and the deterioration width after approximately 500 hours of storage was less than 4 mm. Furthermore, the deterioration width of sealing member 1 was the smallest, being less than 3 mm even after approximately 500 hours of storage.

[0097] Furthermore, no bubbles were observed in any of the sealing members 1 to 4. One possible reason for this is that, in all of the sealing members 1 to 4, the adhesive region R1 was positioned facing the PDLC, so no gaps were formed in the center of the sealing member. Another possible reason is that, in the sealing members 1 to 3, no adhesive was provided near either end of the sealing member, so when a vacuum was drawn, air escaped from the non-adhesive region R2, eliminating any gaps between the sealing member and the laminate.

[0098] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0099] This application claims priority based on a Chinese patent application bearing application number 202410174396.5, filed with the China Patent Office on February 7, 2024, the disclosure of which is incorporated herein in its entirety.

[0100] REFERENCE SIGNS LIST 10 Light control film 20 Laminated glass 21 First glass plate 22 Second glass plate 23 Interlayer 24 Shielding layer 25 Laminate 30 Sealing member 40 Non-adhesive member 50 Electrode 251 First substrate 252 First conductive layer 253 Active layer (light control layer) 254 Second conductive layer 255 Second substrate 301 First sealing member 302 Second sealing member R1 Adhesive region R2 Non-adhesive region

Claims

1. A light-controlling film comprising a laminate and at least one sealing member, wherein the laminate comprises: an active layer; a first substrate and a second substrate arranged to sandwich the active layer; a first conductive layer arranged on the surface of the first substrate facing the active layer; and a second conductive layer arranged on the surface of the second substrate facing the active layer; the sealing member is attached so as to surround and seal the side edges of the laminate in a cross-sectional view of the laminate; the sealing member has at least one adhesive region and at least one non-adhesive region on the surface facing the laminate; and at least one of the adhesive regions is arranged to face the active layer.

2. The light control film according to claim 1, wherein the ratio of the adhesive area to the non-adhesive area of the sealing member is 2:8 to 8:

2.

3. The light-controlling film of claim 1, wherein the sealing member is configured such that, when attached, one of the adhesive regions spans the active layer and extends to the side edge of at least one of the first substrate and the second substrate.

4. The light-controlling film of claim 3, wherein the sealing member is configured such that, in an attached state, one of the adhesive regions extends across the active layer to the side edge of at least one of the first substrate and the second substrate, and further extends to an area facing the surface of the first substrate opposite the surface facing the active layer and / or the surface of the second substrate opposite the surface facing the active layer.

5. A light-controlling film according to any one of claims 1 to 4, wherein the non-adhesive region is provided on at least one of the two ends of the sealing member remote from the active layer, and the non-adhesive region contacts, in an attached state, the surface of the first substrate opposite the surface facing the active layer and / or the surface of the second substrate opposite the surface facing the active layer.

6. The light control film according to claim 1, wherein the plurality of adhesive regions and the plurality of non-adhesive regions are provided at intervals on the surface of the sealing member facing the laminate.

7. The light control film according to claim 1, wherein the non-adhesive region is made of a non-adhesive member, and one end of the non-adhesive member is placed so as to be sandwiched between the end of the sealing member remote from the active layer and the laminate.

8. The light control film according to claim 7, wherein the other end of the non-adhesive member is in contact with the surface of the sealing member opposite to the surface facing the laminate.

9. The light control film according to any one of claims 1 to 8, comprising a plurality of sealing members that partially overlap each other along the thickness direction of the laminate, and the plurality of sealing members are attached so as to individually surround and seal the side edges of the laminate in a plan view.

10. The light-controlling film according to claim 1, wherein the sealing member comprises a first sealing member and a second sealing member, the first sealing member and the second sealing member have the adhesive region in the middle portion of the inner surface facing the laminate, and both end portions are non-adhesive regions, and the first sealing member and the second sealing member are overlapped along the thickness direction of the laminate so as to sandwich one edge of the laminate.

11. The light control film according to claim 1, wherein at least one of the first conductive layer and the second conductive layer of the laminate is connected to an electrode, and at least one of the sealing members is installed so as to seal at least the connection site of the electrode with the adhesive region.

12. A laminated glass comprising: a first glass plate; a second glass plate; an interlayer film sandwiched between the first glass plate and the second glass plate; and the light control film according to any one of claims 1 to 11 surrounded by the interlayer film.

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