Dimming unit

Abstract

To provide a dimming unit capable of suitably sealing a required place including an electrode section without spoiling a function of a dimming film.SOLUTION: A dimming unit includes: a dimming film; an electrode section for applying a drive voltage to the dimming film; and a sealing section for performing sealing by pinching a first area including the electrode section in the dimming film, and exposing a second area without including the electrode section in the dimming film without sealing. The dimming unit further includes a wiring section connected to the electrode section, and the sealing section performs sealing by pinching the electrode section and the first area including the wiring section in the dimming film, and may expose the electrode section and the second area without including the wiring section in the dimming film without sealing.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a dimming unit.

Background Art

[0002] Patent Document 1 describes a dimming unit including a dimming sheet, a support substrate, a covering portion, a pair of wiring portions, and a waterproof adhesive layer. The dimming sheet includes a dimming layer that holds a liquid crystal composition in voids of a polymer network, and a pair of transparent electrode layers that sandwich the dimming layer. The support substrate has an outer shape larger than that of the dimming sheet. The covering portion extends along the outer edge of the dimming sheet on the support substrate to cover the end face of the dimming sheet, and suppresses moisture from entering from the outside of the dimming sheet into the inside of the dimming layer. The pair of wiring portions are each connected to one of the transparent electrode layers and extend to the outside of the support substrate. The waterproof adhesive layers are each positioned between one of the wiring portions and the support substrate to attach each wiring portion to the support substrate. In the dimming unit of Patent Document 1, the dimming sheet is attached to the support substrate in a state where the dimming sheet is located inside the support substrate in a plan view facing the surface of the dimming sheet.

[0003] Patent Document 2 describes a dimming sheet including a first transparent covering substrate having a first bonding surface, a second transparent covering substrate having a second bonding surface, and a dimming film positioned between the first bonding surface and the second bonding surface. The dimming film includes a first transparent electrode film, a second transparent electrode film, and a liquid crystal layer. The first transparent electrode film includes a first electrode layer and a first support film that supports the first electrode layer, and the first support film is bonded to the first bonding surface. The second transparent electrode film includes a second electrode layer and a second support film that supports the second electrode layer, and the second support film is bonded to the second bonding surface. The liquid crystal layer includes a liquid crystal composition that fills the space between the first transparent electrode film and the second transparent electrode film. The dimming sheet of Patent Document 2 further includes a transparent adhesive layer that bonds between the dimming film and the first bonding surface and between the dimming film and the second bonding surface, and the transparent adhesive layer has a thickness of 50 μm or more and 100 μm or less.

Prior Art Documents

Patent Document

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, according to the intensive research of the present inventor, Patent Documents 1 and 2 have room for improvement from the viewpoint of suitably sealing the necessary portions including the electrode portion without impairing the function of the dimming film.

[0006] The present invention has been completed based on the above problems, and an object thereof is to provide a dimming unit that can suitably seal the necessary portions including the electrode portion without impairing the function of the dimming film.

Means for Solving the Problems

[0007] The dimming unit of the present embodiment includes a dimming film, an electrode portion that applies a driving voltage to the dimming film, and a sealing portion that seals by sandwiching a first region including the electrode portion of the dimming film and exposes a second region not including the electrode portion of the dimming film without sealing it, and is characterized by having the same.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a dimming unit that can suitably seal the necessary portions including the electrode portion without impairing the function of the dimming film.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0010] In this specification, "upper surface" and "lower surface" may be defined, for example, as the upper and lower surfaces in the figure (they may also be defined based on the vertical direction in the figure). Also, in this specification, "outer side" and "outer support layer" may be defined as being outside a certain reference (center) layer, or as a layer supported outside a certain reference (center) layer, regardless of the vertical direction in the figure. For example, assume a laminated structure in which a certain reference (center) layer A is provided, layer B is provided on both sides of layer A, and layer C is provided on both sides of layer B. In this case, layer B is an "outer support layer (for example, the first outer support layer)" supported "outside" layer A, and layer C is an "outer support layer (for example, the second outer support layer)" supported "outside" layer A and layer B. In that sense, "outer side" and "outer support layer" may be read as "upper layer" and "upper layer support layer". In this case, it is defined as the upper layer side as it is farther from a certain reference (center) layer, and as the lower layer side as it is closer to a certain reference (center) layer.

[0011] Hereinafter, embodiments will be described with reference to the drawings. However, the drawings are schematic or conceptual, and the dimensions, ratios, etc. of each drawing are not necessarily the same as the actual ones. Also, even when representing the same part between the drawings, the dimensional relationships and ratios may be represented differently from each other. In particular, several embodiments shown below are examples of devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is not specified by the shape, structure, arrangement, etc. of the component parts. In the following description, elements having the same function and configuration are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0012] FIG. 1 is a cross-sectional view showing the structure of a dimming film and an electrode portion. FIG. 2 is a top view showing the structure of a dimming unit. FIG. 3 is a cross-sectional view showing the structure of a heat seal portion. FIG. 4 is a first cross-sectional view showing the structure of a dimming unit. FIG. 5 is a second cross-sectional view showing the structure of a dimming unit.

[0013] As shown in FIGS. 1, 4, and 5, the dimming film 10 has a liquid crystal layer (dimming layer) 11. The liquid crystal layer 11 contains a liquid crystal composition. The liquid crystal layer 11 is composed of, for example, polymer network liquid crystal (PNLC), polymer dispersed liquid crystal (PDLC), capsule-type nematic liquid crystal (NCAP), etc. For example, the polymer network liquid crystal has a three-dimensional network-shaped polymer network and holds liquid crystal molecules in the voids of the polymer network. The liquid crystal molecules contained in the liquid crystal layer 11 have, for example, a positive dielectric anisotropy, and the dielectric constant in the long axis direction of the liquid crystal molecules is larger than the dielectric constant in the short axis direction of the liquid crystal molecules. The liquid crystal molecules are, for example, Schiff base type, azo type, azoxy type, biphenyl type, terphenyl type, benzoic acid ester type, trans type, pyrimidine type, cyclohexanecarboxylic acid ester type, phenylcyclohexane type, dioxane type liquid crystal molecules.

[0014] On the outer side of one surface (the upper surface in FIGS. 1, 4, and 5) of the liquid crystal layer 11, a transparent conductive layer (transparent electrode layer) 12X is provided, and on the outer side of the transparent conductive layer 12X, a PET (Polyethylene Terephthalate) layer 13X is provided. Further, a functional film layer 14X may be provided on the outer side of the PET layer 13X. The functional film layer 14X may contain, for example, at least one of an HC (Hard-Coating) layer, a smoke layer, and a UV (ultraviolet) cut layer. Note that the functional film layer 14X is not drawn in FIG. 1 and is drawn in FIGS. 4 and 5.

[0015] On the outer side of the other surface of the liquid crystal layer 11 (the lower surface in FIGS. 1, 4, and 5), a transparent conductive layer (transparent electrode layer) 12Y is provided, and on the outer side of the transparent conductive layer 12Y, a PET (Polyethylene Terephthalate) layer 13Y is provided. Further, a functional film layer 14Y may be provided on the outer side of the PET layer 13Y. The functional film layer 14Y may include, for example, at least one of an HC (Hard-Coating) layer, a smoke layer, and a UV (ultraviolet) cut layer. Note that the functional film layer 14Y is not depicted in FIG. 1 and is depicted in FIGS. 4 and 5.

[0016] The transparent conductive layers 12X and 12Y are transparent layers having conductivity. Examples of the materials constituting the transparent conductive layers 12X and 12Y include indium tin oxide (ITO), fluorine-doped tin oxide (FTO), tin oxide, zinc oxide, carbon nanotubes (CNT), polymers containing poly(3,4-ethylenedioxythiophene) (PEDOT), multilayer films including Ag alloy thin films, and the like.

[0017] Here, in FIGS. 4 and 5, the PET layers 13X and 13Y and the functional film layers 14X and 14Y are exemplified and described as the "outer support layers" located outside the transparent conductive layers 12X and 12Y. However, other layers may be provided in addition to / replacing the PET layers 13X and 13Y and the functional film layers 14X and 14Y as the "outer support layers" located outside the transparent conductive layers 12X and 12Y. That is, there is freedom in the number and type of the "outer support layers", and various design changes are possible.

[0018] For example, a transparent support layer made of a transparent base material may be provided as the "outer support layer" located outside the transparent conductive layers 12X and 12Y. As the transparent support layer, for example, a glass substrate, a silicon substrate, or a polymer film made of polyethylene, polystyrene, polyethylene terephthalate, polyvinyl alcohol, polycarbonate, polyvinyl chloride, polyimide, polysulfone, cycloolefin polymer, triacetyl cellulose, or the like may be used.

[0019] Furthermore, as the "outer support layer" located outside the transparent conductive layers 12X and 12Y, for example, a layer for protecting the liquid crystal layer 11, the transparent conductive layers 12X and 12Y, a layer contributing to the control of light transmittance in the dimming film 10, a layer for enhancing characteristics such as the strength and heat resistance of the dimming film 10, etc. may be used.

[0020] In this embodiment, the PET layers 13X and 13Y located outside the transparent conductive layers 12X and 12Y are sometimes referred to as the "first outer support layer", and the functional film layers 14X and 14Y located outside the PET layers 13X and 13Y are sometimes referred to as the "second outer support layer".

[0021] The transparent conductive layer 12X and the PET layer 13X, which are sequentially located outside one surface (the upper surface in FIG. 1) of the liquid crystal layer 11, and the transparent conductive layer 12Y and the PET layer 13Y, which are sequentially located outside the other surface (the lower surface in FIG. 1) of the liquid crystal layer 11, are arranged such that their positions in plan view are shifted from each other.

[0022] For example, when focusing on the left side of FIG. 1, a stepped portion DX is provided where the transparent conductive layer 12Y and the PET layer 13Y provided on the other surface (the lower surface in FIG. 1) of the liquid crystal layer 11 protrude to the left of the transparent conductive layer 12X and the PET layer 13X provided on one surface (the upper surface in FIG. 1) of the liquid crystal layer 11. And on the upper surface of the transparent conductive layer 12Y located to the left of the stepped portion DX, an electrode portion 20Y for applying a driving voltage to the dimming film 10 is provided. A wiring portion 25Y is connected to the electrode portion 20Y. The wiring portion 25Y may be composed of FPC (Flexible Printed Circuits).

[0023] Furthermore, when looking at the right side of FIG. 1, a transparent conductive layer 12X and a PET layer 13X provided on one surface (the upper surface in FIG. 1) of the liquid crystal layer 11 protrude to the right of a transparent conductive layer 12Y and a PET layer 13Y provided on the other surface (the lower surface in FIG. 1) of the liquid crystal layer 11, forming a stepped portion DY. And on the upper surface of the transparent conductive layer 12X located to the right of the stepped portion DY, an electrode portion 20X for applying a driving voltage to the dimming film 10 is provided. A wiring portion 25X is connected to the electrode portion 20X. The wiring portion 25X may be composed of FPC (Flexible Printed Circuits).

[0024] When the driving current flows through the transparent conductive layer 12X via the electrode portion 20X and the wiring portion 25X, and the driving current flows through the transparent conductive layer 12Y via the electrode portion 20Y and the wiring portion 25Y in the dimming film 10 configured as described above, a driving voltage is applied between the transparent conductive layers 12X and 12Y, that is, to the liquid crystal layer 11.

[0025] When no driving voltage is applied between the transparent conductive layers 12X and 12Y (in the liquid crystal layer 11), the orientation of the long axis direction of the liquid crystal molecules in the liquid crystal layer 11 is irregular. Therefore, the light incident on the liquid crystal layer 11 is scattered, and the dimming film 10 appears cloudy. That is, the dimming film 10 is opaque.

[0026] On the other hand, when a driving voltage is applied between the transparent conductive layers 12X and 12Y (in the liquid crystal layer 11), the liquid crystal molecules in the liquid crystal layer 11 are aligned, and the long axis direction of the liquid crystal molecules becomes an orientation along the electric field direction between the transparent conductive layers 12X and 12Y. As a result, light easily passes through the liquid crystal layer 11, and the dimming film 10 becomes transparent.

[0027] Note that the dimming film 10 may include a pair of light distribution layers that sandwich the liquid crystal layer 11 between the liquid crystal layer 11 and the transparent conductive layers 12X and 12Y. The light distribution layer is a layer that controls the orientation of the liquid crystal molecules included in the liquid crystal layer 11, and when no driving voltage is applied, the liquid crystal molecules are oriented along the normal direction of the alignment layer. In a configuration including an alignment layer, when a driving voltage is applied between the transparent conductive layers 12X and 12Y (liquid crystal layer 11), the dimming film 10 becomes opaque, and when no driving voltage is applied between the transparent conductive layers 12X and 12Y (liquid crystal layer 11), the dimming film 10 becomes transparent. Examples of the material constituting the alignment layer include polyamides, polyimides, polycarbonates, polystyrenes, polysiloxanes, polyesters such as polyethylene terephthalate and polyethylene naphthalate, and polyacrylates such as polymethyl methacrylate. The alignment treatment for forming the alignment layer is, for example, rubbing treatment, polarized light irradiation treatment, or microfabrication treatment.

[0028] Further, the liquid crystal layer 11 may contain a dye having a predetermined color and not interfering with the movement of the liquid crystal molecules according to the magnitude of the voltage applied to the liquid crystal layer 11. According to such a configuration, a dimming film 10 having a predetermined color is realized.

[0029] The dimming film 10 is, for example, cut out from a large-sized sheet made of a multilayer body including each layer constituting the dimming film 10 into a desired shape and used for various applications. For example, the dimming film 10 may be ordinary transparent glass, but can be applied to various applications such as instant dimming crystal magic films for blocking the view from the inside and outside only at specific times, office partitions, laminated glass, and frosted glass.

[0030] By the way, according to the intensive research of the present inventor, it is required to suitably seal the necessary parts including the electrode part (for example, the electrode part and the wiring part) of the dimming film without impairing its function. However, the conventional methods have not been able to fully meet this requirement. In particular, when using an auxiliary electrode for driving a larger dimming film or a routing wiring for split driving of the dimming film, there is a risk that it may be difficult to effectively seal the extensive area including it.

[0031] For example, as a method for sealing the electrode part and the wiring part of the dimming film, there are a method of applying a curable resin or the like, a method of using a waterproof tape, and a method of using a pouch.

[0032] However, when applying a curable resin, due to the influence of the unevenness of the electrode part and the paintability of the surface, the coating film thickness varies, or in the worst case, an uncoated area occurs. As a result, there is a concern that the reliability of the seal may be reduced due to the intrusion of moisture from the slight gap at that time.

[0033] The above-mentioned Patent Document 1 corresponds to the method of using a waterproof tape, but it is difficult to meet strict temperature and humidity resistance (for example, temperature 85°C / humidity 85% as in-vehicle reliability conditions).

[0034] The above-mentioned Patent Document 2 corresponds to the method of using a pouch. However, since the entire dimming film and the electrode are pouched, the optical performance of the visual recognition area, which is the functional part of the dimming film (the laminated structure part where transparency / opacity is switched), deteriorates.

[0035] The present inventor regarded the above problems as important technical issues and conceived a structure for suitably sealing the necessary parts including the electrode part without impairing the function of the dimming film.

[0036] More specifically, the dimming film is partitioned into a first region including the electrode portion (and the wiring portion) and a second region not including the electrode portion (and the wiring portion). For example, in FIG. 1, a "first region" including the electrode portion 20X (and the wiring portion 25X) located on the right side is partitioned, a "first region" including the electrode portion 20Y (and the wiring portion 25Y) located on the left side is partitioned, and a "second region" not including the electrode portion 20X (and the wiring portion 25X) and the electrode portion 20Y (and the wiring portion 25Y) located in the center is partitioned.

[0037] Then, by sandwiching the "first regions" of the dimming film 10 that include the electrode portion 20X (and the wiring portion 25X) and the electrode portion 20Y (and the wiring portion 25Y) between a pair of heat-sealing portions (sealing portions) 30, it is sealed. On the other hand, the pair of heat-sealing portions (sealing portions) 30 expose the "second region" of the dimming film 10 that does not include the electrode portion 20X (and the wiring portion 25X) and the electrode portion 20Y (and the wiring portion 25Y) without sealing it.

[0038] Thereby, only the first region including the electrode portion (and the wiring portion) is sealed pinpoint (spotwise), while the second region, which is the functional portion of the dimming film (the laminated structure portion where transparency / opacity is switched), is exposed without being sealed, so that the optical performance of the viewing area can be improved (maintained).

[0039] FIGS. 2A, 2B, and 2C illustrate how to divide the first region and the second region when a pair of electrode portions and wiring portions, that is, the electrode portion 20X and the wiring portion 25X and the electrode portion 20Y and the wiring portion 25Y, are provided on the dimming film 10 that is rectangular in top view.

[0040] Figure 2A shows that an electrode portion 20X, a wiring portion 25X, an electrode portion 20Y, and a wiring portion 25Y are provided adjacent to the lower side of the light-adjusting film 10 that is rectangular in top view. The electrode portion 20X is arranged to protrude toward the front side of the paper surface, and the electrode portion 20Y is arranged to protrude toward the back side of the paper surface. Also, a "first region (near the lower side of the light-adjusting film 10 that is rectangular in top view)" including the electrode portion 20X, the wiring portion 25X, the electrode portion 20Y, and the wiring portion 25Y is depicted by filling it with a gray pattern, and the "first region" is sealed by heat sealing. A "second region" that does not include the electrode portion 20X, the wiring portion 25X, the electrode portion 20Y, and the wiring portion 25Y is exposed without being sealed by heat sealing.

[0041] Figure 2B shows that an electrode portion 20X and a wiring portion 25X are provided on the lower side of the light-adjusting film 10 that is rectangular in top view, and an electrode portion 20Y and a wiring portion 25Y are provided on the upper side of the light-adjusting film 10 that is rectangular in top view. The electrode portion 20X is arranged to protrude toward the front side of the paper surface, and the electrode portion 20Y is arranged to protrude toward the back side of the paper surface. Also, a "first region (near the upper side and the lower side of the light-adjusting film 10 that is rectangular in top view)" including the electrode portion 20X, the wiring portion 25X, the electrode portion 20Y, and the wiring portion 25Y is depicted by filling it with a gray pattern, and the "first region" is sealed by heat sealing. A "second region" that does not include the electrode portion 20X, the wiring portion 25X, the electrode portion 20Y, and the wiring portion 25Y is exposed without being sealed by heat sealing. Further, a cross-sectional view taken along the I-I line on the left side of Figure 2B may correspond to the cross-sectional view of Figure 1.

[0042] Figure 2C shows that adjacent to the lower side of the rectangular dimming film 10 in top view, electrode portion 20X, wiring portion 25X, electrode portion 20Y, and wiring portion 25Y are provided. Electrode portion 20X is disposed to protrude toward the front side of the paper surface, and electrode portion 20Y is disposed to protrude toward the back side of the paper surface. Also, an L-shaped routing wiring portion 26X located at the lower left corner in Figure 2C is connected to electrode portion 20X, and an inverted L-shaped routing wiring portion 26Y located at the lower right corner in Figure 2C is connected to electrode portion 20Y. Then, the "first region (near the lower side, left side, and right side of the rectangular dimming film 10 in top view)" including electrode portion 20X, wiring portion 25X, routing wiring portion 26X, electrode portion 20Y, wiring portion 25Y, and routing wiring portion 26Y is filled and drawn with a gray pattern, and the "first region" is sealed by heat sealing. The "second region" that does not include electrode portion 20X, wiring portion 25X, routing wiring portion 26X, electrode portion 20Y, wiring portion 25Y, and routing wiring portion 26Y is exposed without being sealed by heat sealing.

[0043] Referring to FIGS. 3 to 5, the cross-sectional structure of the heat seal portion (sealing portion) 30 will be described. FIG. 3 depicts one of a pair of heat seal portions (sealing portions) 30, which sandwiches each layer (transparent conductive layer 12X and PET layer 13X or transparent conductive layer 12X, PET layer 13X, and functional film layer 14X) provided on one surface (the upper surface in FIGS. 1, 4, and 5) of the dimming film 10. Actually, the other heat seal portion 30 depicted in FIGS. 4 and 5 sandwiches each layer (transparent conductive layer 12Y and PET layer 13Y or transparent conductive layer 12Y, PET layer 13Y, and functional film layer 14Y) provided on the other surface (the lower surface in FIGS. 1, 4, and 5) of the dimming film 10.

[0044] The heat-sealing part 30 has a heat-sealing layer 31 composed of a thermoplastic resin heat-adhesive film. The heat-sealing layer 31 is solid at normal temperature and has the property of liquefying when heated. After applying the heat-sealing part 30 to the "first region" of each layer (transparent conductive layer 12X and PET layer 13X or transparent conductive layer 12X, PET layer 13X, and functional film layer 14X) provided on one surface (the upper surface in FIGS. 1, 4, and 5) of the light-dimming film 10, heating it, and then cooling it, the heat-sealing part 30 can be adhered to seal the "first region". Similarly, after applying the heat-sealing part 30 to the "first region" of each layer (transparent conductive layer 12Y and PET layer 13Y or transparent conductive layer 12Y, PET layer 13Y, and functional film layer 14Y) provided on the other surface (the lower surface in FIGS. 1, 4, and 5) of the light-dimming film 10, heating it, and then cooling it, the heat-sealing part 30 can be adhered to seal the "first region".

[0045] The heat-sealing part 30 (heat-sealing layer 31) has a PET (Polyethylene Terephthalate) layer 32 and an HC (Hard-Coating) layer 33 as protective layers located on the surface opposite to the surface facing the light-dimming film 10. By providing the PET layer 32 and the HC layer 33 as protective layers, the strength and durability of the sealing part of the "first region" of the light-dimming film 10 by the heat-sealing part 30 can be improved.

[0046] The heat-sealing part 30 (heat-sealing layer 31) has a primer layer 34 located on the surface facing the light-dimming film 10. By providing the primer layer 34, the adhesion between the heat-sealing part 30 and the "first region" of the light-dimming film 10 can be improved, and a more excellent sealing function can be obtained.

[0047] Note that the PET layer 32, the HC layer 33, and the primer layer 34 of the heat seal portion 30 (heat seal layer 31) are not essential components, and at least a part of them may be omitted or replaced with other layers. The cross-sectional view of FIG. 3 depicts the PET layer 32, the HC layer 33, and the primer layer 34, while the cross-sectional views of FIGS. 4 and 5 depict only the PET layer 32 and the HC layer 33 with the primer layer 34 omitted.

[0048] Referring to FIG. 4, a first example of the sandwich sealing structure of the "first region" of the dimming film 10 by a pair of heat seal portions 30 will be described. FIG. 4 depicts the sandwich sealing structure of the "first region" including the electrode portion 20Y (and the wiring portion 25Y) located on the left side of FIG. 1, and the same sandwich sealing structure is also applicable to the "first region" including the electrode portion 20X (and the wiring portion 25X) located on the right side of FIG. 1.

[0049] As shown in FIG. 4, a pair of upper and lower heat seal portions 30 sandwich and seal the liquid crystal layer 11 of the "first region" located near the left end of the dimming film 10, the transparent conductive layers 12X and 12Y laminated on both sides thereof, the PET layers 13X and 13Y, and the functional film layers 14X and 14Y, thereby protecting the electrode portion 20Y and the wiring portion 25Y. On the other hand, the pair of upper and lower heat seal portions 30 expose the liquid crystal layer 11 of the "second region" located on the central side of the dimming film 10, the transparent conductive layers 12X and 12Y laminated on both sides thereof, the PET layers 13X and 13Y, and the functional film layers 14X and 14Y without sandwiching them.

[0050] It is preferable that the climbing distance A of the upper heat seal portion 30 to the liquid crystal layer 11 of the "first region" exceeding the step portion DX, the transparent conductive layer 12X laminated on the upper surface thereof, the PET layer 13X, and the functional film layer 14X is 5 mm or less. When the climbing distance A becomes larger than 5 mm, the "second region" becomes too narrow, and there is a risk that the optical performance of the visual recognition area, which is the functional part (the laminated structure part where transparency / opacity is switched) of the dimming film 10, may deteriorate.

[0051] The total thickness h1 of the dimming film 10 is 400 μm or less, and the total thickness h2 of the portion where the dimming film 10 is sandwiched by the pair of heat seal portions 30 is preferably 500 μm or less. Thereby, the size reduction (thinning) of the dimming unit 1 can be achieved, and the applicable objects of the dimming unit 1 can be expanded (made flexible).

[0052] Referring to FIG. 5, a second example of the sandwiching and sealing structure of the "first region" of the dimming film 10 by the pair of heat seal portions 30 will be described. FIG. 5 depicts the sandwiching and sealing structure of the "first region" including the electrode portion 20Y (and the wiring portion 25Y) located on the left side of FIG. 1, but the same sandwiching and sealing structure is also applicable to the "first region" including the electrode portion 20X (and the wiring portion 25X) located on the right side of FIG. 1. For the parts common to the first example in FIG. 4, the overlapping description will be omitted.

[0053] As shown in FIG. 5, the pair of upper and lower heat seal portions 30 sandwich and seal the liquid crystal layer 11 in the "first region" located near the left end of the dimming film 10, the transparent conductive layers 12X and 12Y laminated on both sides thereof, and the PET layers 13X and 13Y, thereby protecting the electrode portion 20Y and the wiring portion 25Y. On the other hand, the pair of upper and lower heat seal portions 30 expose the liquid crystal layer 11 in the "second region" located on the central side of the dimming film 10, the transparent conductive layers 12X and 12Y laminated on both sides thereof, the PET layers 13X and 13Y, and the functional film layers 14X and 14Y without sandwiching them.

[0054] Here, attention is paid to the functional film layers 14X and 14Y located outside the PET layers 13X and 13Y. In the first example of FIG. 4, the functional film layers 14X and 14Y are sandwiched and sealed by the pair of heat seal portions 30, while in the second example of FIG. 5, the functional film layers 14X and 14Y are cut (half cut) with respect to the liquid crystal layer 11, the transparent conductive layers 12X and 12Y laminated on both sides thereof, and the PET layers 13X and 13Y to a position where they are not sandwiched and sealed by the pair of heat seal portions 30.

[0055] That is, the pair of PET layers 13X and 13Y as the first outer support layers are sandwiched by the pair of heat seal portions 30, and the functional film layers 14X and 14Y as the pair of second outer support layers are cut (half cut) to a position where they are not sandwiched by the pair of heat seal portions 30. Further, the end faces (right end faces) of the pair of heat seal portions 30 and the end faces (left end faces) of the functional film layers 14X and 14Y as the pair of second outer support layers face each other with a gap therebetween.

[0056] Thereby, it is possible to absorb the increase in thickness due to the sandwiching and sealing by the pair of heat seal portions 30 (reduce the total thickness h2 of the portion where the light control film 10 is sandwiched by the pair of heat seal portions 30). Further, the step between the functional region (second region) of the light control sheet 10 and the pair of heat seal portions 30 can be reduced. As a result, the size reduction (thinning) of the light control unit 1 can be achieved, and the application target of the light control unit 1 can be expanded (made flexible). Further, for example, it is possible to provide a structure that easily absorbs steps when applied to laminated glass or ground glass, and a structure that easily suppresses bubbles.

[0057] In the above embodiment, the PET layers 13X and 13Y (first outer support layers) and the functional film layers 14X and 14Y (second outer support layers) are exemplified and described as the "plurality of outer support layers" located outside the transparent conductive layers 12X and 12Y. However, the number and types of the "plurality of outer support layers" have degrees of freedom, and various design changes are possible.

[0058] And each of the pair of upper and lower outer support layers may be cut (half-cut) to a position where at least one of them is not sandwiched by the pair of upper and lower heat seal portions 30. For example, a first outer support layer, a second outer support layer, and a third outer support layer may be provided as the "multiple-layer outer support layers", and a part or all of them may be cut (half-cut) to a position where they are not sandwiched by the pair of upper and lower heat seal portions. Alternatively, the first outer support layer is sandwiched by the pair of upper and lower heat seal portions, the second outer support layer and the third outer support layer are cut (half-cut) to positions where they are not sandwiched by the pair of upper and lower heat seal portions, and the cut lengths (half-cut lengths) of the second outer support layer and the third outer support layer may be made different from each other to form a smooth step.

[0059] Thus, the dimming unit of the present embodiment is characterized by having a dimming film, an electrode portion that applies a driving voltage to the dimming film, and a sealing portion that seals by sandwiching a first region including the electrode portion of the dimming film and exposes a second region not including the electrode portion of the dimming film without sealing. Thereby, it is possible to suitably seal a necessary portion including the electrode portion without impairing the function of the dimming film.

[0060] In addition, a large area including auxiliary electrodes and routing wiring in the dimming film can be collectively sealed, and the reliability of the sealing can be improved. Furthermore, only the first region including the electrode portion and the wiring portion is sealed pinpoint (spotwise), while the second region, which is the functional portion (the laminated structure portion where transparency / opacity is switched) of the dimming film, is exposed without being sealed, so that the optical performance of the viewing area can be improved (maintained).

[0061] In addition, when sandwiching and sealing the first region including the electrode portion and the wiring portion, by cutting (half-cutting) at least one of the outer support layers of the dimming film to a position where it is not sandwiched by the pair of heat seal portions, compared with the full-surface pouch of Patent Document 2 described above, for example, a structure that is easy to absorb steps when applied to laminated glass or ground glass, and a structure that is easy to suppress bubbles can be provided.

[0062] The dimming unit of this embodiment can seal a large area (conditions unfavorable for dispensing coating) where routing wiring and auxiliary electrodes are located all at once. Also, compared with the case where a large area is sealed with a curable resin, the sealing performance of the electrode part and wiring part of the dimming film is improved, which can lead to an improvement in reliability. For example, as a result of conducting a test under the conditions of a temperature of 85°C and a humidity of 85% in a state of continuous energization of 80V, in the case of curable resin sealing, the lighting failed after about 500 to 600 hours, whereas in the case of heat seal sealing of this embodiment, the lighting was okay up to 1000 hours (it is considered that lighting for more than 1000 hours is also possible). Furthermore, while taking advantage of the advantages of the pouch structure that covers the entire dimming film for the electrode part and the like, it does not cause a decrease in the optical characteristics (such as haze and transmittance) of the visible area, which is a drawback of the pouch structure.

[0063] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist thereof at the implementation stage. Also, each embodiment may be implemented in appropriate combination, and in that case, the combined effects can be obtained. Furthermore, the above-described embodiment includes various inventions, and various inventions can be extracted by combinations selected from a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, if the problem can be solved and the effects can be obtained, the configuration from which these constituent elements are deleted can be extracted as an invention.

[0064] For example, in the above-described embodiment, as the "sealing part", a pair of heat seal parts that seal by sandwiching the first region including the electrode part (and wiring part) of the dimming film was exemplified and described. However, as long as it can seal by sandwiching the first region including the electrode part (and wiring part) of the dimming film, it may be other than the heat seal part.

Explanation of Reference Numerals

[0065] 1 Dimming unit (dimming device) 10 Dimming film 11 Liquid crystal layer (dimming layer) 12X 12Y Transparent conductive layer (transparent electrode layer) 13X 13Y PET layer (outer support layer, first outer support layer) 14X 14Y Functional film layer (outer support layer, second outer support layer) 20X 20Y Electrode part 25X 25Y Wiring part (FPC) 26X 26Y Lead - through wiring part (wiring part) 30 Heat - seal part (sealing part) 31 Heat - seal layer 32 PET layer (protection layer) 33 HC layer (protection layer) 34 Primer layer DX DY Step part

Claims

1. A dimming film, an electrode part for applying a driving voltage to the dimming film, and a sealing part that seals by sandwiching a first region including the electrode part of the dimming film and exposes a second region not including the electrode part of the dimming film without sealing. A dimming unit characterized by having the above.

2. Further having a wiring part connected to the electrode part, wherein the sealing part seals by sandwiching the first region including the electrode part and the wiring part of the dimming film, and exposes the second region not including the electrode part and the wiring part of the dimming film without sealing. The dimming unit according to Claim 1, characterized by the above.

3. The sealing part is composed of a pair of heat seal parts that seal by sandwiching the first region including the electrode part of the dimming film. The dimming unit according to Claim 1, characterized by the above.

4. The pair of heat seal parts has a protective layer containing PET (Polyethylene Terephthalate) and HC (Hard-Coating), which is located on the surface opposite to the surface facing the dimming film. The dimming unit according to Claim 3, characterized by the above.

5. The pair of heat seal parts has an adhesion layer containing a primer material, which is located on the surface facing the dimming film. The dimming unit according to Claim 3, characterized by the above.

6. The dimming film has a liquid crystal layer, a transparent conductive layer located outside the liquid crystal layer, and a plurality of outer support layers located outside the transparent conductive layer. At least one of the outer support layers is cut to a position not sandwiched by the pair of heat seal parts. The dimming unit according to Claim 3, characterized by the above.

7. A pair of transparent conductive layers are provided outside both surfaces of the liquid crystal layer. A pair of outer support layers are provided outside each of the pair of transparent conductive layers. Each of the pair of outer support layers has at least one layer cut to a position not sandwiched by the pair of heat seal parts. The dimming unit according to Claim 6, characterized by the above.

8. The dimming film has a liquid crystal layer, a transparent conductive layer located outside the liquid crystal layer, a first outer support layer located outside the transparent conductive layer, and a second outer support layer located outside the first outer support layer. The first outer support layer is sandwiched by the pair of heat-sealing portions, The second outer support layer is cut to a position where it is not sandwiched by the pair of heat-sealing portions, The dimming unit according to claim 3, characterized in that.

9. A pair of the transparent conductive layers are provided outside both surfaces of the liquid crystal layer, A pair of the first outer support layer and the second outer support layer are provided outside each of the pair of transparent conductive layers, The pair of first outer support layers are sandwiched by the pair of heat-sealing portions, The pair of second outer support layers are cut to a position where they are not sandwiched by the pair of heat-sealing portions, The dimming unit according to claim 8, characterized in that.

10. The end surfaces of the pair of heat-sealing portions and the end surface of the second outer support layer face each other with a gap therebetween, The dimming unit according to claim 8, characterized in that.

11. The pair of heat-sealing portions are composed of a thermally adhesive film made of a thermoplastic resin, The dimming unit according to claim 3, characterized in that.

12. The dimming film has a liquid crystal layer, a transparent conductive layer and an outer support layer that are sequentially located outside one surface of the liquid crystal layer, and a transparent conductive layer and an outer support layer that are sequentially located outside the other surface of the liquid crystal layer, A stepped portion is provided where the transparent conductive layer and the outer support layer on one surface of the liquid crystal layer protrude more than the transparent conductive layer and the outer support layer on the other surface of the liquid crystal layer, The pair of heat-sealing portions have a climbing distance of 5 mm or less to the transparent conductive layer and the outer support layer on the other surface of the liquid crystal layer beyond the stepped portion, The dimming unit according to claim 3, characterized in that.

13. The total thickness of the dimming film is 400 μm or less, The total thickness of the portion where the dimming film is sandwiched by the pair of heat-sealing portions is 500 μm or less, The dimming unit according to claim 3, characterized in that.

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