Light modulating device and method for manufacturing light modulating module

Abstract

Provided is a light modulating device that is excellent in terms of workability in a step of attaching to a translucent member and in terms of quality retention. Also provided is a method for manufacturing a light modulating module. A light modulation device (10) according to the present embodiment is attached to a translucent member (50), and has a light modulating sheet (20) and protective sheets (30, 40) provided on at least one surface of the light modulating sheet (20). When the peeling force of the protective sheets (30, 40) with respect to the light modulating sheet (20) is defined as a (N / 25 mm), a conditional expression (1) is satisfied. When the peeling force within the light modulating sheet (20) is defined as b (N / 25 mm), a conditional expression (2) is satisfied. Conditional expression (1): 0.08 ≤ a ≤ 0.12. Conditional expression (2): a / b < 1.00.

Description

Light control device and method for manufacturing light control module

[0001] The present invention relates to a method for manufacturing a light control device and a light control module.

[0002] Patent Document 1 describes a transparent laminate film having a transparent conductive film and a protective film. The transparent conductive film is formed by laminating a transparent conductive layer including a metal layer on one side of a transparent film substrate and laminating an anti-reflection layer having releasability on the other side of the transparent film substrate. The protective film is formed by laminating an adhesive layer on one side of the film substrate. The transparent laminate film is formed by bonding the surface of the anti-reflection layer and the surface of the adhesive layer together. Furthermore, Patent Document 1 describes the use of the above-mentioned transparent laminate film as at least one of the transparent electrode films in a light-controlling sheet formed by sandwiching a liquid crystal layer between a pair of transparent electrode films.

[0003] Patent Document 2 describes a light-controlling film comprising a first transparent conductive film, a light-controlling layer, and a second transparent conductive film in this order, and further comprising a protective film disposed only on the side of the first transparent conductive layer opposite the first transparent substrate. The first transparent conductive film comprises a first transparent substrate and a first transparent conductive layer. The first transparent substrate is disposed between the light-controlling layer and the first transparent conductive layer. The second transparent conductive film comprises a second transparent substrate and a second transparent conductive layer disposed on the second transparent substrate. The second transparent substrate is disposed on the side of the second transparent conductive layer opposite the light-controlling layer.

[0004] JP 2009-32475 A Japanese Patent No. 7171181 A

[0005] However, according to the inventor's intensive research, the conventional technologies including the light-control sheet of Patent Document 1 and the light-control film of Patent Document 2 have room for improvement in terms of workability and quality maintenance in the process of attaching them to a light-transmitting member (e.g., glass) (e.g., a laminating glass process).

[0006] More specifically, a light-control sheet (light-control film) is provided with a protective sheet (protective film) on both sides from the time of manufacture to the time of transportation, and it is common to remove (peel off) the protective sheet from the light-control sheet when attaching it to a light-transmitting member.

[0007] However, if the protective sheet cannot be removed properly from the light-adjusting sheet, workability may deteriorate (e.g., takt time may increase). Furthermore, there is a risk that the light-adjusting sheet may be damaged when the protective sheet is removed from the light-adjusting sheet (e.g., the light-adjusting sheet may be bent or peeling may occur between or within the layers of the light-adjusting sheet). Furthermore, if the protective sheet does not adequately protect the light-adjusting sheet (e.g., if the protective sheet partially peels off or lifts from the light-adjusting sheet), scratches, dirt, and foreign matter may adhere to the surface of the light-adjusting sheet, potentially compromising its cleanliness. If the quality of the light-adjusting sheet deteriorates in this way, there is a risk that the light-adjusting function of the affected area may not be achieved.

[0008] The present invention was developed based on the above-mentioned concerns, and aims to provide a method for manufacturing a dimming device and a dimming module that are excellent in terms of workability and quality maintenance in the process of attaching them to a translucent member.

[0009] The light control device of this embodiment is a light control device attached to a light-transmitting member, and includes a light control sheet and a protective sheet provided on at least one surface of the light control sheet, and is characterized in that, when the peel force of the protective sheet from the light control sheet is defined as a (N / 25 mm), the following conditional expression (1) is satisfied: (1) 0.08≦a≦0.12

[0010] The manufacturing method of the dimming module of this embodiment is a manufacturing method of a dimming module in which a dimming device is attached to a light-transmitting member, and the dimming device has a dimming sheet having a first surface that is attached to the light-transmitting member and a second surface that is not attached to the light-transmitting member at a stage before being attached to the light-transmitting member, a first protective sheet that is provided so as to extend beyond the peripheral edge of the first surface of the dimming sheet, and a second protective sheet that is provided so as to fit within the peripheral edge of the second surface of the dimming sheet, and is characterized in that at the stage of attaching the dimming device to the light-transmitting member, the size relationship between the first and second protective sheets is used as an indicator to peel the first protective sheet from the first surface of the dimming sheet, and then the first surface of the dimming sheet is attached to the light-transmitting member, and then the second protective sheet is peeled from the second surface of the dimming sheet.

[0011] The manufacturing method of the light control module of this embodiment is a manufacturing method of a light control module in which a light control device is attached to a light-transmitting member, and the light control device includes, in a stage before being attached to the light-transmitting member, a light control sheet having a first surface to be attached to the light-transmitting member and a second surface not to be attached to the light-transmitting member; a first protective sheet provided on the first surface of the light control sheet and having a first protective layer and a first adhesive layer; and a second protective sheet provided on the second surface of the light control sheet and having a second protective layer and a second adhesive layer. and a second protective sheet having the same, wherein in the step of attaching the dimming device to a light-transmitting member, a force is applied to peel the first protective sheet from the first surface of the dimming sheet, leaving at least a portion of the first adhesive layer, and the remaining adhesive layer is used to attach the first surface of the dimming sheet to the light-transmitting member, and then a force is applied to peel the second protective sheet from the second surface of the dimming sheet, removing it without leaving the second protective layer and the second adhesive layer.

[0012] According to the present invention, it is possible to provide a method for manufacturing a light control device and a light control module that are excellent in terms of workability and quality maintenance in the process of attaching the light-transmitting member.

[0013] 1 is a cross-sectional view showing an example of the configuration of a light control device of a first embodiment. FIG. 2 is a diagram showing the peel force a of the first and second protective sheets against the light control sheet, and the peel force b inside the light control sheet, in a light control device which is a light control sheet with the first and second protective sheets provided thereon. FIG. 3 is a diagram showing an example of the configuration of a light control device of a second embodiment. FIG. 4 is a diagram showing an example of the configuration of a light control device of a third embodiment. FIG. 5 is a first diagram showing the results of an experiment to demonstrate the superiority of the light control device of this embodiment. FIG. 6 is a second diagram showing the results of an experiment to demonstrate the superiority of the light control device of this embodiment. FIG. 7 is a diagram showing an example of a technical problem of a light control device.

[0014] <Definition of Terms, etc.> In this specification, the peel force expressed in the unit "N / 25 mm" may be read as peel strength, and is an index showing how much force (strength) must be applied to separate one member from another, or how much force (strength) must be applied to separate one layer from another layer in a single member. Peel force (peel strength) can also be read as adhesion force (adhesion strength), adhesive force (adhesion strength), sticking force (sticking strength), adhesive force (adhesion strength), etc.

[0015] In this specification, "first (of XX)" and "second (of XX)" may be read interchangeably. For example, in this specification, "the first surface of the light-adjusting sheet" and "the second surface of the light-adjusting sheet" may be read interchangeably, "first protective sheet" and "second protective sheet" may be read interchangeably, and "the first protective layer and first adhesive layer of the first protective sheet" and "the second protective layer and second adhesive layer of the second protective sheet" may be read interchangeably.

[0016] In this specification, the term "light-transmitting member" may be read as a "light-transmitting plate" or a "light-transmitting window," and is used as a concept including a "glass member," a "glass plate," or a "glass window." That is, in this specification, a "glass member (glass plate, glass window)" is described as an example of a "light-transmitting member (light-transmitting plate, light-transmitting window)." However, a "light-transmitting member (light-transmitting plate, light-transmitting window)" may be made of materials other than glass, such as various plastics and other materials. For example, a "light-transmitting member (light-transmitting plate, light-transmitting window)" may be made of polycarbonate.

[0017] In this specification, a "dimming module" refers to a light-transmitting member and a dimming device attached to the light-transmitting member. As its name suggests, a light-transmitting member possesses translucency as its own property. A dimming device ensures the translucency of the light-transmitting member and thus the dimming module (transparent) by not performing its dimming function, while it inhibits the translucency of the light-transmitting member and thus the dimming module (opaque) by performing its dimming function. Dimming devices are available in normal types (normal mode) that are transparent when energized and opaque when deenergized, and reverse types (reverse mode) that are transparent when deenergized and opaque when energized. "Dimmer functioning" refers to the normal type being deenergized and the reverse type being energized, while "dimming function not performing" refers to the normal type being energized and the reverse type being deenergized. In this way, a dimming device can be switched between a transparent state and an opaque state by switching between an energized state and a deenergized state. Here, the transparent state does not mean a visible light transmittance of 100% (does not mean a strict transparent state), and the opaque state does not mean a visible light transmittance of 0% (does not mean a strict opaque state), and each is used to mean a semi-transparent state. Furthermore, in this specification, the "dimming device" may refer to a component of a dimming module, and may refer to the dimming device in a state before being attached to a translucent member.

[0018] In this specification, the dimming method used by the dimming module (dimming device) can be, for example, a polymer dispersed liquid crystal (PDLC) method or a polymer network liquid crystal (PNLC) method. Alternatively, the dimming method used by the dimming module (dimming device) may be one that uses electrochromic (EC), liquid crystal (LC), or suspended particle device (SPD). In other words, the dimming method used by the dimming module (dimming device) has a degree of freedom, and various design changes are possible.

[0019] In this specification, the light control device may have a "light control region (light control portion, light control surface) that switches between a transparent state and an opaque state by switching between an energized state and an unenergized state" and a "sealing region (sealing portion, sealing surface) that seals at least a portion of the periphery of the light control region." The light control region may refer to, for example, substantially the entire area of ​​a light control sheet (light control film) that includes a light control layer, a pair of transparent conductive layers on either side of the light control layer, and a pair of transparent substrate layers on either side of the pair of transparent conductive layers, excluding the periphery. Furthermore, the light control region may be defined as the region where the light control function of the light control sheet (light control film) is exhibited and the visible light transmittance changes, and / or the region of the light control sheet (light control film) where the light control layer is present when viewed in plan. The sealing region may be configured, for example, to include a sealing member (e.g., a material that can be UV-cured in a short time) that seals at least a portion of the periphery of the light control sheet.

[0020] In this specification, the light-transmitting member to which the light control device is attached may include a so-called one-piece or two-piece light-transmitting member. In the case of a one-piece light-transmitting member, the light control device may be attached to the surface of the one-piece light-transmitting member. In the case of a two-piece light-transmitting member, the light control device may be supported by being sandwiched between the two light-transmitting members through an intermediate layer (intermediate film), or the light control device may be attached to the surface of one of the two light-transmitting members. In this way, there is a degree of freedom in the structure for attaching the light control device to the light-transmitting member, and various design modifications are possible.

[0021] In this specification, the terms "upper surface" and "lower surface" as well as the "first surface" and "second surface" may be defined as, for example, the upper surface (first surface) and the lower surface (second surface) in the drawing (these may be defined based on the vertical direction in the drawing). Furthermore, in this specification, the terms "outside" and "outer support layer" may be defined as the outside of a certain reference (center) layer, or as a layer supported on the outside of a certain reference (center) layer, regardless of the vertical direction in the drawing. For example, consider 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" supported on the "outside" of layer A, and layer C is an "outer support layer" supported on the "outside" of layers A and B. In this sense, "outside" and "outside support layer" may be read as "upper layer" and "upper support layer," in which case the further away from a certain reference (center) layer is defined as the upper layer side, and the closer to a certain reference (center) layer is defined as the lower layer side.

[0022] <Conventional Technical Issues> Recently, from the perspectives of adjusting ambient light and protecting privacy, dimming devices that can control transparency or opacity (transmittance) by applying voltage have come to be used in partitions, residential windows, cars, etc. For example, many dimming devices used in building materials change between opaque and transparent states (the opaque state is white) in order to adjust transparency or opacity by controlling the scattering of transmitted light with voltage. However, in recent years, taking into account environmental issues, solar radiation control (light blocking properties), and even design considerations, there has been an increase in devices that can be controlled to black or transparency (or semi-transparent) (the opaque state is black).

[0023] As such, light-controlling devices are products that can instantly switch between transparent and opaque by taking advantage of the properties of liquid crystals, and are often used to switch between open spaces and private spaces.Recently, in the market for light-controlling devices for automobiles and bathrooms, there has been a strong demand for laminated glass rather than light-controlling sheets (light-control films) alone, and there is a need for designs that prevent defects in the light-control sheets (light-control films) during the laminating glass process.

[0024] More specifically, it is preferable to provide protective sheets (protective films) on the front and back surfaces of the light control sheet (light control film) from the time of production until the time of transportation to the next process. By providing protective sheets on the front and back surfaces of the light control sheet (light control film), it is possible to prevent defects in the light control sheet (light control film) caused by removing (peeling off) the protective sheets from the light control sheet when transported to the next process, which is the process of attaching it to a light-transmitting member (laminating glass process).

[0025] However, if the protective sheet cannot be removed properly from the light-adjusting sheet, workability may deteriorate (e.g., takt time may increase). Furthermore, there is a risk of damage to the light-adjusting sheet when removing the protective sheet from the light-adjusting sheet (e.g., the light-adjusting sheet may be bent, or if the light-adjusting sheet is made up of multiple layers, peeling may occur between or within layers). Furthermore, if the protective sheet does not adequately protect the light-adjusting sheet (e.g., if the protective sheet partially peels off or lifts from the light-adjusting sheet), scratches, dirt, and foreign matter may adhere to the surface of the light-adjusting sheet, compromising its cleanliness. If the quality of the light-adjusting sheet deteriorates in this way, there is a risk that the light-adjusting function of the affected area may not be achieved.

[0026] Thus, there are technical issues that, when attaching a light-controlling sheet to a light-transmitting member, it is difficult to peel the protective sheet from the light-controlling sheet (referred to as problem 1), or the protective sheet easily peels off from the light-controlling sheet before attaching the light-controlling sheet to the light-transmitting member (referred to as problem 2). Issues related to problem 1 include deterioration of workability, peeling between the light-controlling layer and the outer support layer (e.g., the transparent conductive layer), peeling inside the light-controlling layer, and peeling inside the outer support layer (e.g., the transparent conductive layer). Issues related to problem 2 include lifting caused by insufficient adhesion of the protective sheet, scratches and stains caused by peeling of the edge of the protective sheet, and deterioration of surface quality due to the adhesion of foreign matter.

[0027] Furthermore, delamination when the light-controlling sheet is made up of multiple layers, particularly when the outer support layer is made up of multiple layers, is also a serious technical issue (referred to as issue 3). More specifically, the pair of outer support layers in the case of the normal type have a pair of transparent conductive layers located on both sides of the light-controlling layer and a pair of transparent substrate layers located on both sides of the pair of transparent conductive layers. Furthermore, the pair of outer support layers in the case of the reverse type have a pair of alignment layers located on both sides of the light-controlling layer, a pair of transparent conductive layers located on both sides of the pair of alignment layers, and a pair of transparent substrate layers located on both sides of the pair of transparent conductive layers. In both the normal type and the reverse type, the pair of outer support layers may have a functional film layer such as a hard coat layer or an adhesive layer.

[0028] In a light-controlling sheet or outer support layer having such a multilayer structure, if adjacent layers peel off from each other, it may adversely affect the function of the light-controlling sheet. According to the inventor's intensive research, it has been found that, among light-controlling sheets or outer support layers having a multilayer structure, the boundary between the light-controlling layer and a pair of alignment layers in the reverse type is prone to tearing (interlayer delamination is likely to occur).

[0029] 7A, 7B, and 7C are diagrams showing examples of technical problems of a light-adjusting device (light-adjusting sheet). Fig. 7A relates to Problem 1, and Figs. 7B and 7C relate to Problem 2.

[0030] In Figure 7A, when peeling the protective sheet from the light-controlling sheet, the light-controlling sheet is pulled, making peeling difficult. In this case, for example, multiple people must hold both ends of the light-controlling device while peeling the protective sheet from the light-controlling sheet, which makes the work less efficient. Furthermore, if the light-controlling sheet is pulled too tightly, the light-controlling sheet may fold poorly, and the defective part may no longer be able to control light.

[0031] In Fig. 7B, slight abrasion or changes over time at the edge of the light control device can easily cause the edge of the protective sheet to lift up from the light control sheet, causing the light control sheet to become dirty. In Fig. 7C, internal lifting of the protective sheet occurs due to inward bending of the light control sheet, causing the light control sheet to become dirty.

[0032] 7A to 7C are due to the characteristics of the light control device itself, which is made up of a light control sheet and a protective sheet, and the characteristics of the process of manufacturing the light control module by attaching the light control device to a light-transmitting member, and are technical problems specific to the manufacturing method of the light control device and light control module of this embodiment (a new technical problem discovered through the inventors' diligent research). In addition, Problem 3, which relates to peeling between adjacent layers assuming a light control sheet or outer support layer having a multilayer structure, for example, peeling between the light control layer and a pair of alignment layers in a reverse type, is also a technical problem specific to the manufacturing method of the light control device and light control module of this embodiment (a new technical problem discovered through the inventors' diligent research).

[0033] <Technical concept of the present invention> The inventors considered the above-mentioned problems to be an important technical issue and came up with the idea of ​​optimally setting the peel force (peel strength) between the light-adjusting sheet and the protective sheet in order to provide a light-adjusting device that is excellent in terms of workability and quality maintenance in the process of attaching it to the translucent member.

[0034] More specifically, the light control device of this embodiment is attached to a light-transmitting member (e.g., glass) (for example, used in a glass lamination process) and includes a light control sheet and a protective sheet provided on at least one surface of the light control sheet. The protective sheet is provided on at least one surface of the light control sheet from the time of manufacture to the time of transportation, and the protective sheet is removed (peeled off) from the light control sheet in the process of attaching the light-transmitting member (e.g., glass) (for example, the glass lamination process).

[0035] When the peel force of the protective sheet from the light-controlling sheet is defined as a (N / 25 mm), the light-controlling device of this embodiment preferably satisfies the following conditional formula (1), and more preferably satisfies the following conditional formula (1'): (1) 0.08≦a≦0.12 (1') 0.09<a<0.11

[0036] When the peeling force inside the light-controlling sheet is defined as b (N / 25 mm), the light-controlling device of this embodiment preferably satisfies the following conditional formula (2), more preferably satisfies the following conditional formula (2'), and even more preferably satisfies the following conditional formula (2"). (2) a / b<1.00 (2') a / b<0.60 (2") a / b<0.40

[0037] When the peeling force inside the light-controlling sheet is defined as b (N / 25 mm), the light-controlling device of this embodiment preferably satisfies the following conditional formula (3), more preferably satisfies the following conditional formula (3'), and even more preferably satisfies the following conditional formula (3"). (3) b ≥ 0.15 (3') b > 0.18 (3") b > 0.30

[0038] The light-controlling sheet may have a light-controlling layer and a pair of outer support layers located on both sides of the light-controlling layer. In this case, the peel force b within the light-controlling sheet may be the peel force between the light-controlling layer and the pair of outer support layers, the peel force within the light-controlling layer, or the peel force within the pair of outer support layers. Regardless of the layer structure of the light-controlling sheet, the force at which a layer within the light-controlling sheet peels from another layer when a force to separate (peel or tear) the light-controlling sheet is applied may be defined as the peel force b within the light-controlling sheet. That is, when a force to separate (peel or tear) one of the layers of the light-controlling sheet is applied and the force is gradually increased, the force at which the light-controlling layer and the pair of outer support layers are first separated may be defined as the peel force b, the force at which the interior of the light-controlling layer is first separated may be defined as the peel force b, and the force at which the interior of the pair of outer support layers is first separated may be defined as the peel force b.

[0039] Furthermore, assuming a laminated structure of the light-controlling sheet having a light-controlling layer and a pair of outer support layers located on both sides of the light-controlling layer, the peel force b within the light-controlling sheet can include the peel force b1 between the light-controlling layer and the pair of outer support layers, the peel force b2 within the light-controlling layer, or the peel force b3 within the pair of outer support layers. In this case, the magnitude relationship between the peel forces b1, b2, and b3 preferably satisfies the relationship b2 > b1 > b3. In other words, it is preferable for peeling to occur (or be induced) within the light-controlling layer. This prevents the transparent conductive layer from being exposed, thereby preventing accidents such as leakage and electric shock when the sheet is applied without noticing peeling.

[0040] By satisfying all or part of conditional expressions (1), (2), and (3), it is possible to optimally set the range of adhesion of the protective sheet to the light-adjusting sheet and the range of adhesion of each layer of the light-adjusting sheet.As a result, the protective sheet can be easily peeled off from the light-adjusting sheet at the installation site, improving workability.In addition, since the protective sheet is not too easy to peel off from the light-adjusting sheet, the occurrence of surface contamination and scratches is suppressed, and the occurrence of defective light-adjusting sheets is suppressed (surface quality can be improved).The above effects are more significantly manifested by satisfying conditional expressions (1'), (2'), (2"), (3'), and (3") within the ranges in which conditional expressions (1), (2), and (3) are satisfied.

[0041] If the lower limit of conditional expression (1) (a<0.08) is exceeded, the risk of peeling or lifting at the edge of the light-controlling sheet increases. If the upper limit of conditional expression (1) (a>0.12) is exceeded, the peeling workability of the protective sheet deteriorates, increasing the risk of folding defects in the light-controlling sheet.

[0042] If the upper limit of conditional expression (2) is exceeded (a / b≧1.00), the peeling workability of the protective sheet deteriorates, and the risk of folding defects in the light controlling sheet increases.

[0043] If the lower limit of conditional expression (3) is exceeded (b<0.15), peeling is likely to occur inside the light-controlling sheet, for example, between the light-controlling layer and the pair of outer support layers, inside the light-controlling layer, or inside the pair of outer support layers.

[0044] The pair of outer support layers located on both sides of the light-controlling layer may be configured with a degree of freedom, and may each include, for example, a transparent conductive layer, a transparent substrate layer, a hard coat layer, and an adhesive layer as functional films. In addition, in the case of a reverse type (reverse mode), the pair of outer support layers may include an alignment layer.

[0045] The protective sheet may be provided on both sides (front and back) of the light-modulating sheet. In this case, the protective sheet may have a first protective sheet provided on the first side (front side) of the light-modulating sheet, which is the side (attached side) that is attached to the light-transmitting member, and a second protective sheet provided on the second side (back side) of the light-modulating sheet, which is the side (exposed side) that is not attached to the light-transmitting member.

[0046] The first protective sheet may be arranged to extend beyond the peripheral edge of the first surface of the light-controlling sheet, and the second protective sheet may be arranged to fit within the peripheral edge of the second surface of the light-controlling sheet. In this case, in a process of attaching the light-controlling device to a light-transmitting member (e.g., glass) (e.g., a laminating glass process), the size relationship between the first and second protective sheets can be used as an indicator to peel the first protective sheet from the first surface of the light-controlling sheet, attach the first surface of the light-controlling sheet to the light-transmitting member, and then peel the second protective sheet from the second surface of the light-controlling sheet. In this way, workability (applicability) can be improved.

[0047] Furthermore, the first protective sheet may have a first protective layer and a first adhesive layer, and the second protective sheet may have a second protective layer and a second adhesive layer. Furthermore, when a force is applied to peel the first protective sheet from the first surface of the light-controlling sheet, at least a portion of the first adhesive layer may remain, and the remaining adhesive layer may be used to attach the first surface of the light-controlling sheet to the translucent member. Furthermore, when a force is applied to peel the second protective sheet from the second surface of the light-controlling sheet, the second protective layer and the second adhesive layer may be removed without remaining. In this case, in the process of attaching the light control device to a light-transmitting member (e.g., glass) (e.g., a laminating glass process), a force is applied to peel the first protective sheet from the first surface of the light control sheet, leaving at least a portion of the first adhesive layer, and the remaining adhesive layer is used to attach the first surface of the light control sheet to the light-transmitting member. After that, a force is applied to peel the second protective sheet from the second surface of the light control sheet, removing it without leaving the second protective layer and the second adhesive layer. In this way, workability (applicability) can be improved.

[0048] 1A, 1B, and 1C are cross-sectional views showing an example of the configuration of a light-adjusting device according to a first embodiment. Fig. 1A illustrates a state in which a protective sheet is attached to a light-adjusting sheet, Fig. 1B illustrates a state in which the protective sheet is being peeled off from the light-adjusting sheet, and Fig. 1C illustrates a state in which the protective sheet has been completely peeled off from the light-adjusting sheet.

[0049] The dimming device 10 has a dimming sheet (dimming film) 20, a first protective sheet (first protective film) 30 provided (attached) to the upper surface (first surface) of the dimming sheet 20, and a second protective sheet (second protective film) 40 provided (attached) to the lower surface (second surface) of the dimming sheet 20.

[0050] The light-controlling sheet 20 includes a light-controlling layer (liquid crystal layer) 21. The light-controlling layer 21 contains a liquid crystal composition. The light-controlling layer 21 is composed of, for example, a polymer network liquid crystal (PNLC: Polymer Network Liquid Crystal), a polymer dispersed liquid crystal (PDLC: Polymer Dispersed Liquid Crystal), or a nematic curvilinear aligned phase (NCAP) liquid crystal. For example, a polymer network liquid crystal has a three-dimensional mesh-like polymer network and holds liquid crystal molecules in the voids of the polymer network. The liquid crystal molecules contained in the light-controlling layer 21 have, for example, a positive dielectric anisotropy, and the dielectric constant in the long axis direction of the liquid crystal molecules is greater than the dielectric constant in the short axis direction of the liquid crystal molecules. The liquid crystal molecules are, for example, Schiff base-based, azo-based, azoxy-based, biphenyl-based, terphenyl-based, benzoate ester-based, tolan-based, pyrimidine-based, cyclohexane carboxylic acid ester-based, phenylcyclohexane-based, or dioxane-based liquid crystal molecules.

[0051] A transparent conductive layer 22X is provided on the outside of one surface (the top surface in the figure) of the light-modulating layer 21, and a transparent substrate layer 23X is provided on the outside of the transparent conductive layer 22X. A transparent conductive layer 22Y is provided on the outside of the other surface (the bottom surface in the figure) of the light-modulating layer 21, and a transparent substrate layer 23Y is provided on the outside of the transparent conductive layer 22Y. In this way, the light-modulating sheet 20 has the light-modulating layer 21, a pair of transparent conductive layers 22X, 22Y located on both sides of the light-modulating layer 21, and a pair of transparent substrate layers 23X, 23Y located on both sides of the pair of transparent conductive layers 22X, 22Y. Each pair of transparent conductive layers 22X, 22Y and transparent substrate layers 23X, 23Y constitutes a "pair of outer support layers" located on both sides of the light-modulating layer 21.

[0052] The transparent conductive layers 22X and 22Y are transparent layers having electrical conductivity. Examples of materials that can be used to form the transparent conductive layers 22X and 22Y include indium tin oxide (ITO), fluorine-doped tin oxide (FTO), tin oxide, zinc oxide, carbon nanotubes (CNT), polymers containing poly(3,4-ethylenedioxythiophene) (PEDOT), and multilayer films containing Ag alloy thin films. The transparent substrate layers 23X and 23Y are layers that contain a material such as PET (Polyethylene Terephthalate).

[0053] In addition, additional or alternative layers may be provided as "outer support layers" located outside the transparent substrate layers 23X and 23Y. In other words, the number and type of "outer support layers" are flexible, allowing for various design modifications. For example, a transparent support layer made of a transparent substrate may be provided as the "outer support layer." Examples of the transparent support layer include 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, etc. Furthermore, examples of the "outer support layer" include a layer for protecting the light-controlling layer 21, the transparent conductive layers 22X and 22Y, and the transparent substrate layers 23X and 23Y, a layer that contributes to controlling the light transmittance of the light-controlling sheet 20, and a layer that enhances the strength, heat resistance, and other properties of the light-controlling sheet 20. For example, the "pair of outer support layers" located on both sides of the light-controlling layer 21 may each include a transparent conductive layer, a transparent substrate layer, a hard coat layer, and an adhesive layer as functional films.

[0054] Although not shown in the figure, the outer peripheral end (end surface) of the light controlling sheet 20 may not be flush, and may be arranged so that their positions are offset from each other when viewed in a plan view.

[0055] For example, when focusing on a certain end (end surface) of the dimming sheet 20, the transparent conductive layer 22X and transparent substrate layer 23X provided on one side (top surface in the figure) of the dimming layer 21 have a half-cut portion that protrudes (projects) laterally beyond the transparent conductive layer 22Y and transparent substrate layer 23Y provided on the other side (bottom surface in the figure) of the dimming layer 21, and this half-cut portion may be provided with an electrode portion and wiring portion (not shown) that apply a driving voltage to the dimming sheet 20 (dimming layer 21).

[0056] Furthermore, when focusing on another end (end surface) of the dimming sheet 20, the transparent conductive layer 22Y and transparent substrate layer 23Y provided on the other surface (bottom surface in the figure) of the dimming layer 21 have a half-cut portion that protrudes (projects) laterally beyond the transparent conductive layer 22X and transparent substrate layer 23X provided on one surface (top surface in the figure) of the dimming layer 21, and this half-cut portion may be provided with an electrode portion and wiring portion (not shown) that apply a driving voltage to the dimming sheet 20 (dimming layer 21).

[0057] In the dimming sheet 20 configured as described above, when a driving current is passed through the transparent conductive layers 22X and 22Y via the electrode portion and wiring portion (not shown), a driving voltage is applied between the transparent conductive layers 22X and 22Y, i.e., to the dimming layer 21.

[0058] When no driving voltage is applied between the transparent conductive layers 22X and 22Y (the light-controlling layer 21), the orientation of the long axes of the liquid crystal molecules in the light-controlling layer 21 is irregular. As a result, light incident on the light-controlling layer 21 is scattered, and the light-controlling sheet 20 appears cloudy (white light-controlling). In other words, the light-controlling sheet 20 is opaque.

[0059] On the other hand, when a drive voltage is applied between the transparent conductive layers 22X and 22Y (the light-controlling layer 21), the liquid crystal molecules in the light-controlling layer 21 are oriented, with the long axis direction of the liquid crystal molecules oriented along the electric field direction between the transparent conductive layers 22X and 22Y. As a result, light is more easily transmitted through the light-controlling layer 21, and the light-controlling sheet 20 becomes transparent. In this way, the light-controlling sheet 20 functions as a normal type (normal mode).

[0060] The light-controlling sheet 20 may also include a pair of alignment layers sandwiching the light-controlling layer 21 between the light-controlling layer 21 and the transparent conductive layers 22X and 22Y. The alignment layers control the alignment of the liquid crystal molecules contained in the light-controlling layer 21, and align the liquid crystal molecules along the normal direction of the alignment layers when no driving voltage is applied. In a configuration including the alignment layers, the light-controlling sheet 20 becomes opaque when a driving voltage is applied between the transparent conductive layers 22X and 22Y (the light-controlling layer 21). When no driving voltage is applied between the transparent conductive layers 22X and 22Y (the light-controlling layer 21), the light-controlling sheet 20 becomes transparent (functioning as a reverse type (reverse mode)). Examples of materials constituting the alignment layers include organic compounds such as polyimide, polyamide, polyvinyl alcohol, and cyanide compounds, inorganic compounds such as silicon oxide and zirconium oxide, and silicone. Examples of alignment treatments for forming the alignment layers include rubbing, polarized light irradiation, and microfabrication.

[0061] In the case of a normal type in which the pair of alignment layers is not provided, the pair of transparent conductive layers 22X, 22Y located on both sides of the dimming layer 21 and the pair of transparent substrate layers 23X, 23Y located on both sides of the pair of transparent conductive layers 22X, 22Y may constitute a "pair of outer support layers." In the case of a reverse type in which the pair of alignment layers is provided, the pair of alignment layers located on both sides of the dimming layer 21, the pair of transparent conductive layers 22X, 22Y located on both sides of the pair of alignment layers, and the pair of transparent substrate layers 23X, 23Y located on both sides of the pair of transparent conductive layers 22X, 22Y may constitute a "pair of outer support layers."

[0062] The light-controlling layer 21 may also contain a dye having a predetermined color that does not interfere with the movement of liquid crystal molecules in response to the magnitude of the voltage applied to the light-controlling layer 21. A dichroic dye and black spacers may also be added to the light-controlling layer 21. This configuration achieves a light-controlling sheet 20 having a predetermined color. In other words, black light control and color light control are possible.

[0063] The light controlling sheet 20 is used for various purposes, for example, by cutting into a desired shape a large sheet made of a multilayer body including each layer that constitutes the light controlling sheet 20. For example, the light controlling sheet 20 can be used for various purposes such as a light controlling film that blocks view from inside and outside only at specific times, which is normally transparent glass, office partitions, laminated glass, frosted glass, etc. The light controlling sheet 20 can also be used to provide a partial sun visor function by being installed in the upper region of the windshield of an automobile.

[0064] The first protective sheet 30 has a transparent substrate layer 31 and an adhesive layer 32 provided on the side of the transparent substrate layer 31 facing the light-adjusting sheet 20. The adhesive force of the adhesive layer 32 causes the first protective sheet 30 (transparent substrate layer 31) to be attached to the light-adjusting sheet 20 (transparent substrate layer 23X).

[0065] The second protective sheet 40 has a transparent substrate layer 41 and an adhesive layer 42 provided on the side of the transparent substrate layer 41 facing the light-adjusting sheet 20. The adhesive force of the adhesive layer 42 causes the second protective sheet 40 (transparent substrate layer 41) to be attached to the light-adjusting sheet 20 (transparent substrate layer 23Y).

[0066] The transparent substrate layer 31 and the transparent substrate layer 41 may have the same material and characteristics, or may have different materials and characteristics. For example, the transparent substrate layer 31 and the transparent substrate layer 41 may be layers containing a material such as PET (Polyethylene Terephthalate).

[0067] The adhesive layer 32 and the adhesive layer 42 may have the same material and characteristics, or may have different materials and characteristics. The adhesive layer 32 and the adhesive layer 42 may be layers containing, for example, an acrylic adhesive. The adhesive layer 32 and the adhesive layer 42 may also be a mixture of one or more resin materials, such as acrylic resin and silicone resin. The adhesive layer 32 and the adhesive layer 42 may also be formed by forming a layer of an adhesive layer material on the surface of the film substrate (the transparent substrate layer 31 and the transparent substrate layer 41), or may be formed by modifying the surface layer of the film substrate (the transparent substrate layer 31 and the transparent substrate layer 41) to impart adhesiveness.

[0068] An example of a method for forming the adhesive layer 32 and the adhesive layer 42 is a method in which a coating liquid prepared by mixing a main material resin or a monomer / oligomer that can become the main material resin, various additives added as needed, and various solvents such as methyl ethyl ketone is applied to one side of the film substrate (transparent substrate layer 31 and transparent substrate layer 41), dried, and polymerized as needed.

[0069] From the time of manufacture to the time of transportation, the light controlling sheet 20 has a first protective sheet 30 attached to its upper surface (first surface) and a second protective sheet 40 attached to its lower surface (second surface) (see FIG. 1A). Then, in a process of attaching the light controlling sheet 20 to a light-transmitting member (e.g., glass) (e.g., a laminating glass process), the first protective sheet 30 and the second protective sheet 40 are removed (peel off) from the light controlling sheet 20 and used (see FIGS. 1B and 1C). That is, the upper surface (first surface) of the light controlling sheet 20 from which the first protective sheet 30 has been removed is attached (attached) to a light-transmitting member 50 made of glass material or polycarbonate. Meanwhile, the lower surface (second surface) of the light controlling sheet 20 from which the second protective sheet 40 has been removed is exposed and not attached (attached) to the light-transmitting member 50. This results in the formation of a light-adjusting module in which the light-adjusting device 10 (the light-adjusting sheet 20 from which the first protective sheet 30 and the second protective sheet 40 have been removed) is attached to the light-transmitting member 50 .

[0070] When the peel force of the first protective sheet 30 and the second protective sheet 40 from the light-adjusting sheet 20 is defined as a (N / 25 mm), the light-adjusting device 10 of the first embodiment preferably satisfies the following conditional formula (1), and more preferably satisfies the following conditional formula (1'): (1) 0.08≦a≦0.12 (1') 0.09<a<0.11

[0071] When the peeling force inside the light-controlling sheet 20 is defined as b (N / 25 mm), the light-controlling device 10 of the first embodiment preferably satisfies the following conditional formula (2), more preferably satisfies the following conditional formula (2'), and even more preferably satisfies the following conditional formula (2"). (2) a / b<1.00 (2') a / b<0.60 (2") a / b<0.40

[0072] When the peeling force inside the light-adjusting sheet 20 is defined as b (N / 25 mm), the light-adjusting device 10 of the first embodiment preferably satisfies the following conditional formula (3), more preferably satisfies the following conditional formula (3'), and even more preferably satisfies the following conditional formula (3"). (3) b ≥ 0.15 (3') b > 0.18 (3") b > 0.30

[0073] The peel force b within the light-controlling sheet 20 may be the peel force b1 between the light-controlling layer 21 and the pair of outer support layers (the transparent conductive layers 22X, 22Y and the transparent substrate layers 23X, 23Y), the peel force b2 within the light-controlling layer 21, or the peel force b3 within the pair of outer support layers (the transparent conductive layers 22X, 22Y and the transparent substrate layers 23X, 23Y). In this case, the magnitude relationship between the peel forces b1, b2, and b3 preferably satisfies the relationship b2 > b1 > b3. In other words, it is preferable that peeling occurs (or is induced) within the light-controlling layer 21. This prevents the transparent conductive layers 22X, 22Y from being exposed, thereby preventing accidents such as electric leakage and electric shock when the sheet is attached without noticing that it has peeled.

[0074] By satisfying all or part of conditional expressions (1), (2), and (3), it is possible to optimally set the range of adhesion of the first protective sheet 30 and the second protective sheet 40 to the light-adjusting sheet 20, and the range of adhesion of each layer of the light-adjusting sheet 20. Therefore, the first protective sheet 30 and the second protective sheet 40 can be easily peeled off from the light-adjusting sheet 20 at the construction site, improving workability. Furthermore, because the first protective sheet 30 and the second protective sheet 40 are not too easily peeled off from the light-adjusting sheet 20, surface contamination and scratches are suppressed, and defects in the light-adjusting sheet 20 are suppressed (surface quality can be improved). The above-mentioned effects are more significantly manifested by satisfying conditional expressions (1'), (2'), (2"), (3'), and (3") within the ranges in which conditional expressions (1), (2), and (3) are satisfied.

[0075] If the lower limit of conditional expression (1) is exceeded (a<0.08), there is a high risk of peeling or lifting at the edge of the light-controlling sheet 20. If the upper limit of conditional expression (1) is exceeded (a>0.12), the ease of peeling the first protective sheet 30 and the second protective sheet 40 deteriorates, increasing the risk of the light-controlling sheet 20 failing to fold.

[0076] If the upper limit of conditional expression (2) is exceeded (a / b≧1.00), the ease of peeling the first protective sheet 30 and the second protective sheet 40 will deteriorate, increasing the risk of the light controlling sheet 20 failing to fold.

[0077] If the lower limit of conditional expression (3) is exceeded (b<0.15), peeling is likely to occur inside the light-modulating sheet 20. For example, there is a high risk of peeling occurring between the light-modulating layer 21 and the pair of outer support layers (the transparent conductive layers 22X, 22Y and the transparent substrate layers 23X, 23Y), peeling occurring inside the light-modulating layer 21, or peeling occurring inside the pair of outer support layers (the transparent conductive layers 22X, 22Y and the transparent substrate layers 23X, 23Y).

[0078] Here, the peel force a of the first protective sheet 30 and the second protective sheet 40 relative to the light-adjusting sheet 20 can be set (determined, controlled), for example, by adjusting the adhesive strength of the adhesive layers 32, 42. The adhesive strength of the adhesive layers 32, 42 can be controlled by the adhesive compounding ratio and the thickness of the adhesive layer. Furthermore, the peel force a of the first protective sheet 30 and the second protective sheet 40 relative to the light-adjusting sheet 20 can be set (determined, controlled) by adjusting the combination (compatibility) of the materials of the first protective sheet 30, the second protective sheet 40, and the light-adjusting sheet 20.

[0079] Furthermore, the peel force b inside the light-controlling sheet 20 can be controlled by the laminated structure of the light-controlling sheet 20 as well as the combination of materials and thicknesses of each layer of the light-controlling layer 20 .

[0080] FIG. 2 illustrates the peel force a of the first protective sheet 30 and the second protective sheet 40 against the light-adjusting sheet 20, and the peel force b within the light-adjusting sheet 20, in the light-adjusting device 10, which is the light-adjusting sheet 20 provided with the first protective sheet 30 and the second protective sheet 40. When these peel forces a and b satisfy all or part of conditional expressions (1), (2), and (3), a light-adjusting device 10 that is excellent in terms of workability and quality maintenance in the process of attaching it to the light-transmitting member 50 can be realized. This effect is more pronounced when conditional expressions (1'), (2'), (2"), and (3') are satisfied within the range in which conditional expressions (1), (2), and (3) are satisfied.

[0081] Second Embodiment Fig. 3 is a diagram showing an example of the configuration of a light control device according to a second embodiment, which illustrates a state in which a protective sheet is attached to a light control sheet.

[0082] As shown in Figure 3, in the second embodiment of the dimming device 10, the size of the first protective sheet 30 provided (attached) to the upper surface (first surface) of the dimming sheet 20 and the size of the second protective sheet 40 provided (attached) to the lower surface (second surface) of the dimming sheet 20 are different from each other.

[0083] The upper surface (first surface) of the light-modulating sheet 20 is the surface (attached surface) that is attached to the light-transmitting member 50, and the size of the first protective sheet 30 that is provided (attached) thereon is relatively large. On the other hand, the lower surface (second surface) of the light-modulating sheet 20 is the surface (exposed surface) that is not attached to the light-transmitting member 50, and the size of the second protective sheet 40 that is provided (attached) thereon is relatively small.

[0084] More specifically, the first protective sheet 30 is arranged so as to extend beyond the peripheral edge of the upper surface (first surface) of the light-adjusting sheet 20, and the second protective sheet 40 is arranged so as to fit within the peripheral edge of the lower surface (second surface) of the light-adjusting sheet 20 (set to a size slightly smaller than the peripheral edge).

[0085] In the second embodiment, in the process of attaching the light-adjusting device 10 to the light-transmitting member 50, the size relationship between the first protective sheet 30 and the second protective sheet 40 is used as an index (mark) to peel the first protective sheet 30 from the upper surface (first surface) of the light-adjusting sheet 20, and after the upper surface (first surface) of the light-adjusting sheet 20 is attached to the light-transmitting member 50, the second protective sheet 40 can be peeled from the lower surface (second surface) of the light-adjusting sheet 20. In this way, workability (applicability) can be improved. After the upper surface (first surface) of the light-modulating sheet 20 is attached to the light-transmitting member 50, the peripheral portion of the light-transmitting member 50 is generally covered with a frame member (not shown) such as a sash, but because the second protective sheet 40 is provided to fit within the peripheral portion of the lower surface (second surface) of the light-modulating sheet 20 (its size is set to be slightly smaller than the peripheral portion), the second protective sheet 40 can be easily peeled off from the lower surface (second surface) of the light-modulating sheet 20. In other words, the second protective sheet 40 can be prevented from interfering with or getting in the way of a frame member (not shown) such as a sash.

[0086] In the second embodiment, as in the first embodiment, by satisfying all or part of conditional expressions (1), (2), and (3), it is possible to optimally set the range of adhesion of the first protective sheet 30 and the second protective sheet 40 to the light-adjusting sheet 20, and the range of adhesion of each layer of the light-adjusting sheet 20. This makes it possible to realize a light-adjusting device 10 that is excellent in terms of workability and quality maintenance in the process of attaching it to the light-transmitting member 50.

[0087] 4A and 4B are diagrams showing an example of the configuration of a light control device according to a third embodiment. Fig. 4A illustrates a state in which a protective sheet is attached to a light control sheet, and Fig. 4B illustrates a state in which the protective sheet has been peeled off from the light control sheet.

[0088] In the light control device 10 of the third embodiment, when force is applied to peel the first protective sheet 30 from the upper surface (first surface) of the light control sheet 20, at least a portion of the first adhesive layer 32 remains to form a residual adhesive layer 32′, and this residual adhesive layer 32′ can be used to attach the upper surface (first surface) of the light control sheet 20 to the light-transmitting member 50. Furthermore, when force is applied to peel the second protective sheet 40 from the lower surface (second surface) of the light control sheet 20, the second protective layer 41 and the second adhesive layer 42 are removed without remaining.

[0089] In the third embodiment, in the process of attaching the light-adjusting device 10 to the light-transmitting member 50, a force is applied to peel the first protective sheet 30 from the upper surface (first surface) of the light-adjusting sheet 20, leaving at least a portion of the first adhesive layer 32 remaining as a residual adhesive layer 32′. After using the residual adhesive layer 32′ to attach the upper surface (first surface) of the light-adjusting sheet 20 to the light-transmitting member 50, a force is applied to peel the second protective sheet 40 from the lower surface (second surface) of the light-adjusting sheet 20, removing the second protective layer 41 and the second adhesive layer 42 without leaving any residue. This improves workability (applicability). That is, after removing the first protective sheet 30 and the second protective sheet 40 from the light-adjusting sheet 20, there is no need to prepare or apply a separate component (e.g., a separate adhesive or glue) to attach the light-adjusting sheet 20 to the light-transmitting member 50.

[0090] In the third embodiment, the adhesive layer 32 of the first protective sheet 30 may be divided into a first adhesive region that is strongly adhered to and integrated with the upper surface (first surface) of the light-adjusting sheet 20, and a second adhesive region that is strongly adhered to and integrated with the first protective layer 31. In this case, when force is applied to peel the first protective sheet 30 from the upper surface (first surface) of the light-adjusting sheet 20, the second adhesive region of the adhesive layer 32 is peeled off (removed) together with the first protective layer 31, and the first adhesive region of the adhesive layer 32 remains on the light-adjusting sheet 20 side as a residual adhesive layer 32′.

[0091] In the third embodiment, as in the first embodiment, by satisfying all or part of conditional expressions (1), (2), and (3), it is possible to optimally set the range of adhesion of the first protective sheet 30 and the second protective sheet 40 to the light-adjusting sheet 20, and the range of adhesion of each layer of the light-adjusting sheet 20. This makes it possible to realize a light-adjusting device 10 that is excellent in terms of workability and quality maintenance in the process of attaching it to the light-transmitting member 50.

[0092] Furthermore, the third embodiment may be combined with the second embodiment, and in the dimming device 10 of the third embodiment, the first protective sheet 30 may be arranged so as to extend beyond the peripheral edge of the upper surface (first surface) of the dimming sheet 20, and the second protective sheet 40 may be arranged so as to fit within the peripheral edge of the lower surface (second surface) of the dimming sheet 20 (it may be set to a size slightly smaller than the peripheral edge).

[0093] <Numerical Examples & Demonstration Experiments> The inventors conducted demonstration experiments to demonstrate the superiority of the dimming device of this embodiment. Fig. 5 is a first diagram showing the results of experiments to demonstrate the superiority of the dimming device of this embodiment. Fig. 5 shows the results of demonstration experiments for Numerical Examples 1-3 and Comparative Examples 1-5.

[0094] In the demonstration experiment, samples according to Numerical Examples 1-3 and Comparative Examples 1-5 were prepared, and each sample was evaluated for whether it satisfied conditional expressions (1), (2), and (3), and for the level of protective film peeling workability, light control film folding defects, edge protective film peeling, and protective film lifting.

[0095] Regarding the workability of peeling the protective film, if the protective film could be peeled off by hand, it was evaluated as "○", and if it could not be peeled off by hand, it was evaluated as "×". Regarding the folding defect of the light-controlling film, if the light-controlling was not performed without folding, it was evaluated as "○", and if the light-controlling was not performed due to folding, it was evaluated as "×". Regarding the peeling of the edge protective film, if the protective film at the edge did not peel off naturally, it was evaluated as "○", and if the protective film at the edge peeled off naturally, it was evaluated as "×". Regarding the lifting of the protective film, if the lifting of the protective film did not occur in a band-like shape, it was evaluated as "○", and if the lifting of the protective film occurred in a band-like shape, it was evaluated as "×". For each evaluation item, "○" corresponded to the pass line of the demonstration experiment, and "×" corresponded to the fail line of the demonstration experiment. In other words, if the evaluations of the protective film peeling workability, light control film folding failure, edge protective film peeling, and protective film lifting were all "○", it was considered to be the pass mark for the demonstration experiment, and if there was even one "×" in the evaluations of the protective film peeling workability, light control film folding failure, edge protective film peeling, and protective film lifting, it was considered to be the fail mark for the demonstration experiment.

[0096] In FIG. 5, the areas of the samples according to Numerical Examples 1-3 and Comparative Examples 1-5 that do not satisfy the constituent requirements of this embodiment are shown with a grayscale background, and the areas that satisfy the constituent requirements of this embodiment are shown with a white background without a grayscale.

[0097] 5, Numerical Example 1-3, which satisfies the conditional expressions (1), (2), and (3) that are the respective constituent requirements (all constituent requirements) of this embodiment, was evaluated as "○" in all items of the protective film peeling workability, light control film folding failure, edge protective film peeling, and protective film lifting, which corresponds to the pass mark of the demonstration experiment. In other words, it was possible to realize a light control device that is excellent in terms of workability and quality maintenance in the process of attaching to the light-transmitting member.

[0098] On the other hand, Comparative Example 1-5, which does not satisfy all of the conditional expressions (1), (2), and (3), which are the respective constituent requirements (all constituent requirements) of this embodiment, particularly conditional expression (1), was evaluated as "x", which corresponds to the failure line of the demonstration experiment, in at least one of the items of protective film peeling workability, light control film folding failure, edge protective film peeling, and protective film lifting. In other words, it was not possible to realize an excellent light control device in terms of workability and quality maintenance in the process of attaching it to the light-transmitting member.

[0099] 6A to 6E are second diagrams showing the results of an experiment to demonstrate the superiority of the light control device of this embodiment. 6A to 6E show the steps of a peel strength test in the demonstration experiment.

[0100] A large sheet consisting of a multilayer body with a protective sheet attached to one side of the light-controlling sheet is prepared, and a strip-shaped measurement sample of the desired shape (e.g., width 25 mm, length 200 mm or more) is cut out from this large sheet (Figures 6A and 6B).

[0101] The protective sheet of the measurement sample is peeled off from one end in the longitudinal direction by more than half, so that it protrudes from the other end in the longitudinal direction (Figure 6C). In this state, one end and the other end in the longitudinal direction of the measurement sample are fixed and supported by a thin metal plate (Figure 6D). Then, one end of a tensile tester is clamped to one end in the longitudinal direction of the metal plate (the end where the protective sheet was peeled off from the light-controlling sheet), and the other end of the tensile tester is clamped to the protective sheet peeled off from the light-controlling sheet. The peel strength is measured by pulling at a specified speed (e.g., 30 mm / min).

[0102] 6A to 6E above illustrate the measurement of the peel force a (N / 25 mm) of the protective sheet against the light-controlling sheet, but a similar measurement method can also be applied to the peel force b (N / 25 mm) inside the light-controlling sheet. For example, the peel strength may be measured by clamping both ends of the light-controlling sheet (without the protective sheet attached) in a tensile tester and pulling at a specified speed (e.g., 30 mm / min). More specifically, with both ends of the light-controlling sheet without the protective sheet attached clamped in a tensile tester, the peel strength required to peel from one end to the middle in the longitudinal direction may be measured, starting from one boundary of each layer of the light-controlling sheet (e.g., between the light-controlling layer and a pair of outer support layers).

[0103] The method for measuring the peel force a (N / 25 mm) of the protective sheet against the light-adjusting sheet and the peel force b (N / 25 mm) inside the light-adjusting sheet is not limited to the example given here, and various design modifications are possible.

[0104] As described above, the light control device of this embodiment is a light control device attached to a light-transmitting member, and includes a light control sheet and a protective sheet provided on at least one side of the light control sheet. When the peeling force of the protective sheet from the light control sheet is defined as a (N / 25 mm), conditional formula (1) is satisfied. When the peeling force inside the light control sheet is defined as b (N / 25 mm), conditional formula (2) is satisfied. This makes it possible to realize a light control device that is excellent in terms of workability and quality maintenance in the process of attaching it to a light-transmitting member (e.g., glass) (e.g., a laminating glass process). (1) 0.08≦a≦0.12 (2) a / b<1.00

[0105] The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention.

[0106] This application is based on Japanese Patent Application No. 2024-083939, filed on May 23, 2024, the contents of which are incorporated herein in their entirety.

Claims

1. A light control device attached to a light-transmitting member, comprising: a light control sheet; and a protective sheet provided on at least one surface of the light control sheet, wherein, when the peel force of the protective sheet from the light control sheet is defined as a (N / 25 mm), the following conditional formula (1) is satisfied: (1) 0.08≦a≦0.12 2. The light control device according to claim 1, wherein the following conditional expression (2) is satisfied when the peeling force inside the light control sheet is defined as b (N / 25 mm): (2) a / b<1.00 3. The light control device according to claim 1, wherein the following conditional expression (3) is satisfied when the peeling force inside the light control sheet is defined as b (N / 25 mm): (3) b≧0.15 4. The dimming device according to claim 2 or 3, characterized in that the dimming sheet has a dimming layer and a pair of outer support layers located on both sides of the dimming layer, and the peel force b inside the dimming sheet is the peel force between the dimming layer and the pair of outer support layers, the peel force inside the dimming layer, or the peel force inside the pair of outer support layers.

5. The light control device according to claim 4, wherein each of the pair of outer support layers includes a transparent conductive layer, a transparent substrate layer, a hard coat layer, and an adhesive layer as functional films.

6. A dimming device as described in claim 1 or claim 2, characterized in that the protective sheet comprises: a first protective sheet provided on a first surface of the dimming sheet; and a second protective sheet provided on a second surface of the dimming sheet.

7. The dimming device of claim 6, wherein the first surface of the dimming sheet is the surface that is attached to the translucent member, the second surface of the dimming sheet is the surface that is not attached to the translucent member, the first protective sheet is arranged to extend beyond the peripheral edge of the first surface of the dimming sheet, and the second protective sheet is arranged to fit within the peripheral edge of the second surface of the dimming sheet.

8. The light control device described in claim 6, characterized in that: the first surface of the light control sheet is the surface that is attached to the translucent member; the second surface of the light control sheet is the surface that is not attached to the translucent member; the first protective sheet has a first protective layer and a first adhesive layer; the second protective sheet has a second protective layer and a second adhesive layer; when a force is applied to peel the first protective sheet from the first surface of the light control sheet, at least a portion of the first adhesive layer remains, and the remaining adhesive layer can be used to attach the first surface of the light control sheet to the translucent member; and when a force is applied to peel the second protective sheet from the second surface of the light control sheet, the second protective layer and the second adhesive layer are removed without remaining.

9. A method for manufacturing a light control module in which a light control device is attached to a light-transmitting member, wherein the light control device has a light control sheet having a first surface attached to the light-transmitting member and a second surface not attached to the light-transmitting member before being attached to the light-transmitting member, a first protective sheet provided so as to extend beyond the peripheral edge of the first surface of the light control sheet, and a second protective sheet provided so as to fit within the peripheral edge of the second surface of the light control sheet, and wherein, in the stage of attaching the light control device to the light-transmitting member, the size relationship between the first and second protective sheets is used as an indicator to peel the first protective sheet from the first surface of the light control sheet, and then the first surface of the light control sheet is attached to the light-transmitting member, and then the second protective sheet is peeled from the second surface of the light control sheet.

10. A method for manufacturing a light control module for attaching a light control device to a light-transmitting member, wherein the light control device comprises: a light control sheet having a first surface attached to the light-transmitting member and a second surface not attached to the light-transmitting member in a stage before the light control device is attached to the light-transmitting member; a first protective sheet provided on the first surface of the light control sheet and having a first protective layer and a first adhesive layer; and a second protective sheet provided on the second surface of the light control sheet and having a second protective layer and a second adhesive layer; and during the stage of attaching the light control device to the light-transmitting member, a force is applied to peel the first protective sheet from the first surface of the light control sheet, leaving at least a portion of the first adhesive layer, and the first surface of the light control sheet is attached to the light-transmitting member using the remaining adhesive layer, and then a force is applied to peel the second protective sheet from the second surface of the light control sheet, removing it without leaving the second protective layer and the second adhesive layer. A method for manufacturing a light control module.

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