JP7622549B2 - Light control film with adhesive layer and method for attaching light control film with adhesive layer to glass surface - Google Patents

Description

The present invention relates to a light control film that is attached to a glass surface and a method for attaching the film.

A light control film is a film that can adjust and control the transmission and blocking of light rays. Such light control films are well known, and generally have a structure in which a liquid crystal layer 11 is sandwiched between two electrode films 12 and 13, as shown in FIG. 1. As shown in the figure, the electrode film 12 is a flexible transparent film 12a having a transparent electrode 12b laminated on one side thereof, and the transparent electrode 12b is laminated so as to face the liquid crystal layer 11. Similarly to the electrode film 12, the other electrode film 13 is a flexible transparent film 13a having a transparent electrode 13b laminated on one side thereof, and the transparent electrode 13b is laminated so as to face the liquid crystal layer 11. By applying a voltage to both electrodes 12b and 13b, the optical properties of the liquid crystal layer 11 change. For example, by applying a voltage, the liquid crystal layer becomes cloudy and opaque, blocking light rays, and on the other hand, by stopping the application of the voltage, the liquid crystal layer becomes transparent and transmits light rays. There are also known light-control films in which, depending on the type of liquid crystal, the liquid crystal layer becomes transparent and transmits light when a voltage is applied, and becomes opaque and blocks light when the voltage application is stopped.

Such light-control films are used for a variety of purposes, but a typical application is to attach them to the surface of building windows or automobile windows to adjust or control the amount of sunlight that enters through the windows.

When attaching a light-control film to a glass surface in this way, it has been customary to use an acrylic adhesive in the past (see Patent Document 1). That is, first, an acrylic adhesive is laminated onto the light-control film, and the resulting light-control film with the adhesive layer is attached to the glass surface.

However, acrylic adhesives have a strong adhesive force, and therefore, when they are bonded to a glass surface, air bubbles are easily trapped between the light-control film and the glass surface. When air bubbles are trapped, the surface of the light-control film becomes uneven, impairing its appearance, and also impairing the function of the light-control film itself. In addition, when a part of the light-control film is bonded to the glass surface, it is impossible to adjust its position. On the other hand, in order to trap air or readjust the position, it is possible to peel off the light-control film that has been bonded once and then re-bond it, but as mentioned above, acrylic adhesives have a strong adhesive force, and this makes it difficult to peel off. In this way, when bonding a light-control film to a glass surface using an acrylic adhesive, air bubbles are easily trapped, and it is difficult to peel off and re-bond it, so it was necessary to accurately align the film from the beginning and carefully bond it to prevent air bubbles from being trapped.

For this reason, the pieces were glued together using the following steps:

That is, first, water containing a surfactant (hereafter referred to as "application water") is sprayed evenly onto the glass surface to form a thin film of application water on the surface.

Next, the release film protecting the acrylic adhesive layer of the light control film is peeled off to expose the acrylic adhesive layer.

Next, the light-control film with the exposed acrylic adhesive layer is temporarily fixed on the coating of the application water formed by spraying. The light-control film is then slid onto this coating of application water to align it. For example, if the glass is a window pane in a building, the light-control film is aligned to the frame. At this time, the coating of application water is between the acrylic adhesive layer and the glass surface and acts as a lubricant, so the light-control film can be slid easily.

After aligning them in this way, strong pressure is applied with a squeegee or similar to expel the application water and air between the acrylic adhesive layer and the glass surface, and the final adhesion is achieved. Note that even at this time, the film of application water mentioned above still acts as a lubricant.

JP 2019-45612 A

However, with this method, it was necessary to spray a large amount of application water onto the glass surface to form the aforementioned coating of application water. This not only had the drawback of consuming a large amount of water, but also created the problem that, if the glass was a window glass in a house, there was a risk of exposing the living environment to water droplets, and it was necessary to evacuate and protect the living space during construction work to prevent flooding of the living environment.

In addition, if air bubbles were trapped during the temporary fastening, it was necessary to apply extremely strong pressure using a squeegee or similar to expel the air bubbles.

Therefore, the present invention aims to provide a light control film with an adhesive layer that can be easily applied to glass surfaces.

As a means for solving the above problems, a first aspect of the present invention is a light control film that changes between a transparent state and an opaque state depending on whether or not a voltage is applied;
A pressure-sensitive adhesive layer laminated on one surface of the light-control film;
A release film that is peelably attached to the surface of the pressure-sensitive adhesive layer,
the adhesive strength when left for 30 minutes in an environment of 23° C. and 55% RH in a state where the adhesive layer is adhered to a glass surface is in the range of 0.01 to 0.41 (unit: N/25 mm);
The light control film with the pressure-sensitive adhesive layer is characterized in that the static friction coefficient between the release film and the glass surface is 0.8 or less.

The second aspect is a light-controlling film with an adhesive layer, characterized in that in the light-controlling film described in the first aspect, the adhesive layer contains a thermoplastic elastomer.

The third aspect is a light-control film with an adhesive layer, characterized in that the thickness of the release film in the light-control film according to the first or second aspect is 188 μm or less.

The fourth aspect is a light-control film with an adhesive layer, characterized in that the light-control film according to any one of the first to third aspects has a cut line for cutting off at least a partial area of the release film.

The fifth aspect is the light-control film with an adhesive layer, characterized in that the cut line in the light-control film according to the fourth aspect penetrates the release film.

The sixth aspect is a light-control film with an adhesive layer, characterized in that in the light-control film described in the fourth aspect, the cut line reaches midway through the thickness direction of the release film.

The seventh aspect is a light control film with an adhesive layer, characterized in that the light control film according to any one of the first to third aspects has an embossed line for cutting out at least a partial area of the release film.

The eighth aspect is a light control film with an adhesive layer, characterized in that in the light control film according to any one of the fourth to seventh aspects, the cut lines or embossed lines are straight or wavy.

The ninth aspect is a light control film with an adhesive layer, characterized in that in the light control film according to any one of the fourth to eighth aspects, the cut lines or embossed lines are solid lines or dashed lines.

The tenth aspect is a light-control film with an adhesive layer, characterized in that in the light-control film according to any one of the first to ninth aspects, the glass is a windowpane of a building or a windowpane of a moving object.

Further, the method for attaching the light control film according to the present invention is a method for attaching a light control film with an adhesive layer to a glass surface, comprising the steps of:
The light control film with the pressure-sensitive adhesive layer has a static friction coefficient between a release film that is peelably attached to the surface of the pressure-sensitive adhesive layer and a glass surface of 0.8 or less,
an end pressure-sensitive adhesive layer exposing step of peeling off the release film of the pressure-sensitive adhesive layer-attached light-control film at its end to expose the pressure-sensitive adhesive layer at the end;
a positioning step of sliding the light control film with the adhesive layer in a state in which the adhesive layer at the end portion is exposed by the edge adhesive layer exposing step on a glass surface to position the light control film;
a temporary fixing step of temporarily fixing the pressure-sensitive adhesive layer-attached light control film positioned in the positioning step to a glass surface;
A bonding process in which the remaining release film is peeled off from the adhesive layer-attached light control film temporarily attached in the temporary attachment process, and the exposed adhesive layer is bonded to a glass surface,
In the lamination step, the adhesive layer-attached light control film is adhered to the glass surface via the adhesive layer such that the adhesion strength when left for 30 minutes in an environment of 23° C. and 55% RH is in the range of 0.01 to 0.41 N/25 mm.
This is a method for attaching a light control film with an adhesive layer to a glass surface.

The present invention provides a light control film with an adhesive layer that can be easily applied to glass surfaces.

FIG. 1 is an explanatory cross-sectional view of a light control film constituting a pressure-sensitive adhesive layer-attached light control film according to an embodiment of the present invention. FIG. 2 is an explanatory cross-sectional view of an adhesive film constituting the adhesive layer-attached light control film according to an embodiment of the present invention. FIG. 3 is an explanatory cross-sectional view of a release film constituting a pressure-sensitive adhesive layer-attached light control film according to an embodiment of the present invention. FIG. 4 relates to a light control film with a pressure-sensitive adhesive layer according to an embodiment of the present invention, in which FIG. 4(a) is an explanatory cross-sectional view and FIG. 4(b) is an explanatory perspective view. FIG. 5 relates to a light control film with an adhesive layer according to an embodiment of the present invention, and both FIG. 5(a) and FIG. 5(b) are explanatory perspective views for explaining a method of attaching the film to a glass surface.

The light-control film with an adhesive layer of the present invention has three essential components: a light-control film, an adhesive layer, and a release film.

The light-control film has the property of changing between a transparent and opaque state depending on whether or not a voltage is applied, and any known light-control film can be used.

The adhesive layer serves to adhere the light-control film to the glass surface, and may be applied by directly coating the adhesive onto the light-control film, but it may also be applied by applying an adhesive layer onto an adhesive film substrate and then attaching it to the light-control film.

The release film also plays a role in protecting the surface of the adhesive layer until it is attached to the glass surface by the adhesive layer. As described below, in the process of peeling off a part of the release film to expose the adhesive layer, and then sliding the light control film with the adhesive layer in position while leaving a part of the adhesive layer exposed, the release film also plays a role in protecting the adhesive layer other than the part exposed for temporary attachment, and allowing it to slide easily and smoothly in contact with the glass surface.

Hereinafter, an embodiment of the present invention will be described with reference to the attached drawings. Fig. 1 is an explanatory cross-sectional view of a light-control film 10 constituting a light-control film 100 with an adhesive layer according to an embodiment of the present invention, Fig. 2 is an explanatory cross-sectional view of an adhesive film 20, and Fig. 3 is an explanatory cross-sectional view of a release film 30. Fig. 4(a) is an explanatory cross-sectional view of the light-control film 100 with an adhesive layer, and Fig. 4(b) is an explanatory perspective view thereof.

As described above, the light control film 10 may be a known light control film (see FIG. 1). This light control film 10 has a structure in which a liquid crystal layer 11 is sandwiched between two electrode films 12 and 13. As shown in the figure, the electrode film 12 is a flexible transparent film 12a having a transparent electrode 12b laminated on one side thereof, and the transparent electrode 12b is laminated so as to face the liquid crystal layer 11. Similarly to the electrode film 12, the other electrode film 13 is a flexible transparent film 13a having a transparent electrode 13b laminated on one side thereof, and the transparent electrode 13b is laminated so as to face the liquid crystal layer 11. By applying a voltage to both electrodes 12b and 13b, the optical properties of the liquid crystal layer 11 change. For example, by applying a voltage, the liquid crystal layer becomes cloudy and opaque, blocking light rays, and by stopping the application of the voltage, the liquid crystal layer becomes transparent and transmits light rays. Depending on the type of liquid crystal, the light control film may be one in which the liquid crystal layer becomes transparent and transmits light when a voltage is applied, and the liquid crystal layer becomes opaque and blocks light when the voltage application is stopped.

Next, the adhesive film 20 is formed by laminating an adhesive layer 22 on one side of an adhesive film substrate 21 and coating and laminating an adhesive layer 23 on the other side.

The adhesive layer 22 is used to attach the adhesive film 20 to the light control film 10, and a highly adhesive adhesive such as a urethane adhesive or an acrylic adhesive can be used.

On the other hand, the adhesive layer 23 is used to adhere the adhesive film 20 to the glass surface, and it is necessary to use an adhesive with relatively low adhesion.

Specifically, when the adhesive layer 23 is attached to the glass surface and left for 30 minutes in an environment of 23°C and 55% RH, the adhesion must be in the range of 0.01 to 0.41 N/25 mm. If the adhesion is higher than this, it becomes difficult to slide the light control film with the adhesive layer for positioning while leaving part of the adhesive layer exposed. For this reason, in this case, as in the conventional method, it becomes necessary to spray a large amount of application water containing a surfactant onto the glass surface to form a thin film on the surface, then temporarily fix it and slide it over this film to position it.

The adhesive used in this adhesive layer 23 can be, for example, a thermoplastic elastomer. For example, a polyolefin-based thermoplastic elastomer.

Films in which this thermoplastic elastomer is coated and laminated on one side of an adhesive film substrate are commercially available as adhesive films, so this commercially available adhesive film can also be used as the adhesive film 20 by providing an adhesive layer 22 on the adhesive film substrate side. As a commercially available adhesive film, for example, Gel Poly by Panac Corporation can be used. This Gel Poly is made by coating one side of a polyester film of various thicknesses as the adhesive film substrate 21 with a polyolefin-based thermoplastic elastomer to form an adhesive layer 23. However, even with this Gel Poly, the adhesion to the glass surface varies depending on the product, so it is necessary to use one with an adhesion in the range of 0.01 to 0.41 N/25 mm from the product.

This gel poly has a protective release film attached to the surface of the adhesive layer 23, so when applying it to the present invention, it is necessary to remove the protective release film and instead apply the release film 30 described below.

As shown in FIG. 3, the release film 30 can be constructed by laminating a release agent layer 32 on one side of a release film substrate 31. As described above, the release film 30 is attached to the adhesive layer 23 of the adhesive film 20 in an easily peelable manner, and protects the surface of the adhesive layer 23 until it is bonded to the glass surface. For this reason, the release agent layer 32 is laminated on the surface facing the adhesive layer 23.

On the other hand, the release film substrate 31 is to be in contact with the glass surface to which it is to be attached. As described later, the release film 30 is peeled off at its end, and the release film 30 is left exposed at the end of the adhesive layer 23. The release film 30 is then slid on the glass surface to position the adhesive layer 23 on which the release film 30 is laminated. In this positioning step, the release film substrate 31 must be in contact with the glass surface and slide smoothly. For this reason, the static friction coefficient between the release film substrate 31 and the glass surface to which it is to be attached must be 0.8 or less. If the static friction coefficient exceeds 0.8, it is difficult to slide the release film substrate 31 in the positioning step. If it is difficult to slide the release film substrate 31 in this way, it is necessary to use a large amount of application water in the positioning step, as in the conventional method. Preferably, the static friction coefficient is 0.8 or less.

A plastic film such as a polyester film can be suitably used as the release film substrate 31. However, the static friction coefficient between the plastic film and the glass surface varies depending on the presence or absence, type or amount of additives contained in the polyester film, the presence or absence and type of surface treatment, etc., and also varies depending on the lot, etc., so it is desirable to select and use a film having a static friction coefficient with the glass surface of 0.8 or less from among commercially available films. If the thickness is too thick, it becomes difficult to attach or position the film on the glass surface, so it is desirable to have a thickness of 188 μm or less. An example of a commercially available film that can be used as the release film substrate 31 is Lumirror T60 from Toray Industries, Inc., which has a thickness of 30 to 188 μm.

The release agent layer 32 can be made of silicone resin cured with various curing agents. For example, a platinum-based curing agent can be used as the curing agent.

Next, we will explain how to attach this light control film 100 with an adhesive layer to a glass surface. Figures 5(a) and 5(b) are both perspective views for explaining how to attach the film to a glass surface.

This light control film 100 with an adhesive layer can be attached to a glass surface through an edge adhesive layer exposure process, a positioning process, a temporary fixing process, and a bonding process.

The edge adhesive layer exposure process is a process in which the release film 30 of the adhesive layer-attached light control film 100 is peeled off at its edge to expose the adhesive layer at the edge. For this process, as shown in FIG. 5(a), it is desirable to provide a cut line 30x at the edge of the release film 30 to enable it to be cut. The cut line 30x can be provided using a blade such as a cutter or scissors, but an embossed line formed by embossing may also be used instead of the cut line 30x.

In the illustrated example, the cut line 30x is straight and dashed, and has a depth that penetrates the release film 30 and reaches the surface of the adhesive layer 23, but this is not limited to this. For example, the cut line 30x may be a curved line such as a wavy line. It may also be a solid line instead of a dashed line. The cut line 30x may reach partway through the thickness direction of the release film 30 but not reach the surface of the adhesive layer 23. However, it is desirable that the release film 30 can be easily cut at this cut line 30x.

The cut line 30x may be provided at the construction site where the light control film 10 is attached to the glass surface, but it is preferable to provide it at the manufacturing factory where the adhesive layer-attached light control film 100 is manufactured. If the cut line 30x is provided at the manufacturing factory in this way and the adhesive layer-attached light control film 100 with the cut line 30x provided is shipped, the work at the construction site will be easier.

In this edge adhesive layer exposing process, the release film 30 is cut along the cut line 30x, and the release film 30 located on the edge side is removed to expose the edge adhesive layer 23a. Figure 5(b) shows this state.

Then, the next positioning step is to place the adhesive layer-attached light control film 100, with the release film 30 laminated thereon, on the glass surface with the end adhesive layer 23a exposed, and slide it over the glass surface to position it. At this time, it is desirable that the exposed end adhesive layer 23a does not come into contact with the glass surface, but because the adhesion between the adhesive layer 23 and the glass surface is relatively small, the adhesive layer-attached light control film 100 can be slid even if the two come into contact. And because the static friction coefficient between the release film 30 and the glass surface is also small, it is easy to slide the adhesive layer-attached light control film 100.

Next, in the temporary fixing process, the positioned light control film 100 with adhesive layer is adhered by the exposed edge adhesive layer 23a. As mentioned above, the adhesive layer 23 has a relatively small adhesion to the glass surface, so if a mistake is made, it can be peeled off and reapplied.

Finally, the bonding process involves peeling and removing the remaining release film 30 from the adhesive layer-attached light control film 100 that has been temporarily attached at the ends, and bonding the adhesive layer-attached light control film 100 to the glass surface with the exposed adhesive layer 23. Although the adhesion between the adhesive layer 23 and the glass surface is relatively small, the adhesion when left for 30 minutes in an environment of 23°C and 55% RH is in the range of 0.01 to 0.41 N/25 mm, so the adhesion of the adhesive layer-attached light control film 100 whose entire surface is thus bonded to the glass surface is sufficient and it will not peel off from the glass surface inadvertently.

Typical examples of glass to which this adhesive layer-attached light control film 100 is attached include window glass in buildings, or window glass in moving objects such as automobiles and trains. However, the glass is not limited to these, and may also be fixtures, etc.

The present invention will be explained below with examples and comparative examples.

These examples and comparative examples will be explained separately: process A, in which the adhesive layer-attached light-control film 100 is manufactured at a manufacturing plant; construction process B, in which the adhesive layer-attached light-control film 100 is attached to the surface of a window glass at the construction site; and result C, which explains the results.

Example 1
(A) Process for producing the light control film 100 with an adhesive layer To 100 parts by weight of an addition polymerization type silicone resin (KS-841 manufactured by Shin-Etsu Chemical Co., Ltd.), 0.1 parts by weight of a platinum-based curing agent (PL-50T manufactured by Shin-Etsu Chemical Co., Ltd.) was added, and the mixture was further diluted with a mixed solvent of n-hexane and toluene to prepare a coating material for a release agent layer (coating material 31 ₁ ) with a solid content of 5% by weight.

A polyester film (Lumirror T60, manufactured by Toray Industries, Inc.) having a thickness of 38 μm was used as the release film substrate 31, and the coating material for the release agent layer ₃₁₁ was applied to one side of the film, followed by drying and curing at 120° C. to produce the release film 30. The thickness of the resulting release agent layer 32 was 100 nm.

Next, we prepared a gelboli made by Panac Corporation. This gelboli is made of polyester films of various thicknesses that serve as an adhesive film substrate 21, with one side coated with a polyolefin thermoplastic elastomer to form an adhesive layer 23, and a protective release film attached to the surface of this adhesive layer 23.

Then, this protective release film was peeled off, and instead the release film 30 produced in the previous step was attached so that the release agent layer 31 faced the surface of the adhesive layer 23. In addition to this, OCA (Optical Clear Adhesive) was bonded as the adhesive layer 22 to the surface of the adhesive film substrate 21 to produce an adhesive film 20 with the release film 30 attached. For the OCA, TD06A manufactured by Tomoegawa Paper Co., Ltd., in which release films were attached to both sides of the OCA layer, was used, and one of the release films on both sides was peeled off and removed, and the exposed OCA layer was adhered to the surface of the adhesive film substrate 21 to form the bond.

A normal mode type light control film 10 (NW001, manufactured by Toppan Printing) was laminated to the adhesive layer 22 surface of the film obtained in the above process (adhesive film 20 laminated with release film 30) to produce a light control film 100 with an adhesive layer. That is, the release film protecting the OCA layer was peeled off and removed, and the exposed OCA layer was adhered to the light control film 10 to form the laminate.

This light control film 100 with an adhesive layer does not have a cut line 30x. Therefore, as described below, the cut line 30x is provided on this light control film 100 with an adhesive layer at the construction site.

The release film 30 was peeled off and removed from the thus obtained light control film 100 with the adhesive layer to expose the adhesive layer 23, and this adhesive layer 23 was brought into contact with the blue glass surface for adhesion. The adhesion strength (adhesion strength after storage) was measured after leaving the film for 30 minutes in an environment of 23°C and 55% RH according to JIS Z-0237, and was found to be 0.15 N/25 mm.

The static friction coefficient between the release film 30 of the adhesive layer-attached light control film 100 and the blue glass surface was 0.35. This static friction coefficient was measured using a Type 94i manufactured by Shinto Scientific Co., Ltd., with the adhesive layer-attached light control film 100 and the blue glass surface together.

(B) Installation Step The size of the light-gathering window to which the adhesive layer-attached light-control film 100 was attached was set to 1 m×1.5 m, and an adhesive layer-attached light-control film 100 of 1 m×1.5 m was prepared in accordance with this window size.

A cut line 30x was then made in the release film 30 using a blade to form an isosceles right triangle with sides of 0.5 m each and the corner serving as a vertex. The cut line 30x was a straight, solid line, and its depth was such that it penetrated the release film 30 and reached the surface of the adhesive layer 23.

Next, the release film 30 in the shape of a right-angled isosceles triangle located on the corner side of the cut line 30x was removed to expose the adhesive layer 23 at this position.

The light control film 100 with the adhesive layer, with the end adhesive layer 23a exposed in this manner, was placed on the glass surface of the light-receiving window so that its release film substrate (polyester film) 31 was in contact with the glass surface, and was then slid over the glass surface to position it.

Then, the light control film 100 with the adhesive layer positioned on the glass surface was temporarily attached by adhering the exposed end adhesive layer 23a to the glass surface. Note that the adhesive portion of the light control film 100 with the adhesive layer temporarily attached in this manner can be easily peeled off, so positioning and temporary attachment could be repeated many times.

Finally, the remaining release film 30 was peeled off and removed, while the exposed adhesive layer 23 was adhered to the glass surface, and the entire adhesive layer-attached light control film 100 was laminated to the glass surface. At this time, the adhesive layer-attached light control film 100 was laminated from the temporarily attached end to the other end while automatically excluding air. As a result, no air bubbles remained between the laminated adhesive layer-attached light control film 100 and the glass surface.

(C) Results As described above, in this example, it was confirmed that the film can be attached to the glass surface of the daylight window without the need for application water, and that the positioning and temporary fixing can be repeated many times. In addition, a part of the adhesive layer 23 can be exposed, and the film can be aligned and bonded with the end adhesive layer 23a. In addition, in the bonding process in which the entire light control film 100 with the adhesive layer is bonded, the bonding process proceeds while automatically removing air, so there is no need to apply strong pressure in any of the positioning process, temporary fixing process, and bonding process. Therefore, each process can be easily performed, and the light control film 10 is not damaged.

Example 2
(A) Process for Producing the Light Control Film 100 with an Adhesive Layer A light control film 100 with an adhesive layer was produced in the same manner as in Example 1, except that a polyester film having a thickness of 125 μm (Lumirror T60, manufactured by Toray Industries, Inc.) was used as the release film substrate 31.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.34 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.60.

(B) Application Step In the same manner as in Example 1, the film was attached to the glass surface of a skylight.

(C) Results As in Example 1, the light control film 10 could be attached to the glass surface of the light-receiving window without the need for application water, and the positioning and temporary fixing could be repeated many times. Furthermore, no strong pressure was required in any of the positioning, temporary fixing, and bonding processes, so each process could be easily carried out without damaging the light control film 10.

Example 3
(A) Process for Producing the Light Control Film 100 with an Adhesive Layer A light control film 100 with an adhesive layer was produced in the same manner as in Example 1, except that a polyester film having a thickness of 188 μm (Lumirror T60, manufactured by Toray Industries, Inc.) was used as the release film substrate 31.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.01 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.35.

(B) Application Step In the same manner as in Example 1, the film was attached to the glass surface of a skylight.

(C) Results As in Example 1, the light control film 10 could be attached to the glass surface of the light-receiving window without the need for application water, and the positioning and temporary fixing could be repeated many times. Furthermore, no strong pressure was required in any of the positioning, temporary fixing, and bonding processes, so each process could be easily carried out without damaging the light control film 10.

Example 4
(A) Process for manufacturing the light control film 100 with an adhesive layer The light control film 100 with an adhesive layer was manufactured in the same manner as in Example 1. However, in this example, the cut line 30x was formed at the manufacturing factory. The cut line 30x was formed using a blade to form a right-angled isosceles triangle with a side length of 0.5 m, with the corner of the light control film 100 with an adhesive layer as the apex, in the same manner as in Example 1, and was a straight, solid line with a depth that penetrated the release film 30 and reached the surface of the adhesive layer 23.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.29 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.52.

(B) Application Process As described above, the film was attached to the glass surface of the skylight in the same manner as in Example 1, except that the process of forming the cut lines 30x was carried out in the manufacturing factory.

(C) Results As in Example 1, the light control film 10 could be attached to the glass surface of the light-receiving window without the need for application water, and the positioning and temporary fixing could be repeated many times. Furthermore, no strong pressure was required in any of the positioning, temporary fixing, and bonding processes, so each process could be easily carried out without damaging the light control film 10.

In this example, the process of forming the cut lines 30x was carried out at the manufacturing plant, so there was no need for blades such as cutters or scissors at the construction site, proving to be extremely convenient.

Example 5
(A) Process for manufacturing the light control film 100 with an adhesive layer The light control film 100 with an adhesive layer was manufactured in the same manner as in Example 1. However, in this example, the cut line 30x was formed at the manufacturing factory. The cut line 30x was formed using a blade to form a right-angled isosceles triangle with a side length of 0.5 m, with the corner of the light control film 100 with an adhesive layer as the apex, as in Example 1. The cut line 30x was also linear and solid as in Example 1, but the depth was a depth that did not penetrate the release film 30 but reached the middle of its thickness direction, and varied in the range of 3 to 30 μm.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.21 N/25 mm.

The static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.45.

(B) Application Process As described above, the film was attached to the glass surface of the skylight in the same manner as in Example 1, except that the process of forming the cut lines 30x was carried out in the manufacturing factory.

(C) Results As in Example 1, the light control film 10 could be attached to the glass surface of the light-receiving window without the need for application water, and the positioning and temporary fixing could be repeated many times. Furthermore, no strong pressure was required in any of the positioning, temporary fixing, and bonding processes, so each process could be easily carried out without damaging the light control film 10.

In this example, the process of forming the cut lines 30x was carried out at the manufacturing plant, so there was no need for blades such as cutters or scissors at the construction site, proving to be extremely convenient.

Example 6
(A) Process for manufacturing the light control film 100 with an adhesive layer The light control film 100 with an adhesive layer was manufactured in the same manner as in Example 1. However, in this example, the cut line 30x was formed at the manufacturing factory. The cut line 30x was formed using a blade to form a right-angled isosceles triangle with a side length of 0.5 m, with the corner of the light control film 100 with an adhesive layer as the apex, as in Example 1. The cut line 30x is linear as in Example 1, but is perforated. The depth is a depth that does not penetrate the release film 30 but reaches the middle of its thickness direction, and varies in the range of 3 to 30 μm.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.41 N/25 mm.

The static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.45.

(B) Application Process As described above, the film was attached to the glass surface of the skylight in the same manner as in Example 1, except that the process of forming the cut lines 30x was carried out in the manufacturing factory.

(C) Results As in Example 1, the light control film 10 could be attached to the glass surface of the light-receiving window without the need for application water, and the positioning and temporary fixing could be repeated many times. Furthermore, no strong pressure was required in any of the positioning, temporary fixing, and bonding processes, so each process could be easily carried out without damaging the light control film 10.

In this example, the process of forming the cut lines 30x was carried out at the manufacturing plant, so there was no need for blades such as cutters or scissors at the construction site, proving to be extremely convenient.

(Example 7)
(A) Process for manufacturing the light control film 100 with an adhesive layer The light control film 100 with an adhesive layer was manufactured in the same manner as in Example 1. However, in this example, embossed lines were formed in the manufacturing factory instead of the cut lines 30x. The embossed lines were formed in a straight and solid shape using a metal embossing roll. And, like the cut lines 30x in Example 1, these embossed lines were provided so as to form a right-angled isosceles triangle with a side length of 0.5 m, with the corners of the light control film 100 with an adhesive layer as vertices. Also, the cut lines 30x were straight like those in Example 1, but in the form of perforations.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.29 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with an adhesive layer and the blue glass surface was 0.50.

(B) Construction process As described above, the embossed lines were formed at the manufacturing factory, so no cut lines were formed at the construction site. In the (B2) edge pressure-sensitive adhesive layer 23a exposure process, the release film 30 in the shape of a right-angled isosceles triangle located on the corner side from the embossed lines was removed to expose the pressure-sensitive adhesive layer 23 at this position. At this time, the release film 30 could be easily peeled off by hand.

Apart from the above, it was attached to the glass surface of the skylight in the same manner as in Example 1.

(C) Results As in Example 1, the light control film 10 could be attached to the glass surface of the light-receiving window without the need for application water, and the positioning and temporary fixing could be repeated many times. Furthermore, no strong pressure was required in any of the positioning, temporary fixing, and bonding processes, so each process could be easily carried out without damaging the light control film 10.

In this example, the process of forming the cut lines 30x was carried out at the manufacturing plant, so there was no need for blades such as cutters or scissors at the construction site, proving to be extremely convenient.

(Example 8)
In this example, a thick film is used as the release film substrate 31 .

(A) Step of manufacturing the light control film 100 with the adhesive layer A polyester film (Lumirror T60: manufactured by Toray Industries, Inc.) having a thickness of 250 μm was used as the release film substrate 31. In other respects, the light control film 100 with the adhesive layer was manufactured in the same manner as in Example 1.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.35 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with an adhesive layer and the blue glass surface was 1.50.

(B) Construction process As in Example 1, we first tried to create a cut line 30x at the corner of the adhesive layer-attached light-control film 100. However, because the release film substrate 31 was as thick as 250 μm, we did not cut it at the construction site but instead prepared it to the specified size in advance.

We also tried peeling off the entire release film 30 to expose the entire adhesive layer 23 and then adjusting the position while laminating the glass, but we were unable to move the adhesive layer 23 that was attached to the glass surface, and it became necessary to be careful with the positioning process.

For this reason, the positioning and bonding were carried out using 1 liter of construction water as a lubricant and a squeegee.

(C) Results In Example 8, a light control film having a thickness of 200 μm or more was used compared to the other examples. Therefore, construction was carried out using construction water with caution. In addition, because of the thickness, strong pressure was applied to remove air bubbles, and damage to the light control film 10 was confirmed, although slight. However, after construction, a light control glass window that was practically usable was provided, as in the other examples.

(Comparative Example 1)
In this example, a release film 30 having a large coefficient of static friction with the glass surface is used.

(A) Process for producing a light control film 100 with an adhesive layer To 50 parts by weight of an addition polymerization type silicone resin (LTC-750A manufactured by DuPont Toray Specialty Materials Co., Ltd.), 50 parts by weight of a release adjuster (SD7292 manufactured by DuPont Toray Specialty Materials Co., Ltd.) and 0.1 parts by weight of a platinum-based curing agent (SRX-212 manufactured by Shin-Etsu Chemical Co., Ltd.) were added, and the mixture was further diluted with a mixed solvent of n-hexane and toluene to prepare a coating material for a release agent layer (coating material 31 ₂ ) with a solid content of 2% by weight.

A polyethylene film having a thickness of 100 μm was used as the release film substrate 31, and one side of the film was subjected to a corona discharge treatment, after which the coating material for the release agent layer ₃₁₂ was applied to the treated surface, dried at 40° C., and cured by irradiating with ultraviolet light using an ultraviolet irradiator (Fusion H bulb), to produce the release film 30. The thickness of the resulting release agent layer 32 was 100 nm.

In all other respects, the light control film 100 with the adhesive layer was manufactured in the same manner as in Example 1.

As in Example 1, the adhesion strength after storage between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.19 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.85.

(B) Construction process First, a cut line 30x was provided at the corner of the adhesive layer-attached light control film 100, as in Example 1. The cut line 30x was formed using a blade to form a right-angled isosceles triangle with a side length of 0.5 m, with the corner of the adhesive layer-attached light control film 100 as the apex, as in Example 1, and was a straight, solid line with a depth that penetrated the release film 30 and reached the surface of the adhesive layer 23.

Next, the release film 30 in the shape of a right-angled isosceles triangle located on the corner side of the cut line 30x was removed to expose the adhesive layer 23 at this position.

Then, the light control film 100 with the adhesive layer, with the end adhesive layer 23a exposed in this manner, was placed on the glass surface of the light-receiving window so that its release film substrate (polyethylene film) 31 was in contact with the glass surface, and an attempt was made to position it by sliding it over the glass surface, as in Example 1. However, the release film 30 did not slide well against the glass surface, and positioning was not possible.

Therefore, we had no choice but to peel off the entire release film 30 to expose the entire adhesive layer 23, and then tried to attach it while adjusting the position, but we were unable to move the adhesive layer 23 that was attached to the glass surface, and therefore were unable to position it properly.

For this reason, the positioning and lamination were carried out using 1 liter of application water as a lubricant and a squeegee.

(C) Results In this example, the film could not be attached to the glass surface of the light-receiving window without using application water. Therefore, the positioning process, the temporary fixing process, and the attachment process were not easy. In addition, it was necessary to apply strong pressure to remove air bubbles, and damage to the light control film 10, although slight, was confirmed.

(Comparative Example 2)
This example also uses a release film 30 having a large coefficient of static friction with the glass surface.

(A) Process for manufacturing the light control film 100 with an adhesive layer A 50 μm thick unstretched polypropylene film (Pylane CT P1146, manufactured by Toyobo Co., Ltd.) was used as the release film substrate 31, and one side of the film was subjected to a corona discharge treatment. The release agent layer coating material 31 ₂ used in Comparative Example 1 was then applied to the treated side, dried at 40° C., and cured by irradiating ultraviolet rays with an ultraviolet irradiator (Fusion H bulb), to manufacture the release film 30. In other respects, the light control film 100 with an adhesive layer was manufactured in the same manner as in Example 1.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.21 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.90.

(B) Construction process As in Example 1, a cut line 30x was provided at the corner of the adhesive layer-attached light-control film 100, and the release film 30 was removed to expose an end adhesive layer 23a in the shape of a right-angled isosceles triangle with a side length of 0.5 m and whose apex was the corner of the adhesive layer-attached light-control film 100.

Then, similar to Example 1, this light control film 100 with an adhesive layer was placed on the glass surface of the light-receiving window, and an attempt was made to position it by sliding it over the glass surface. However, the release film 30 did not slide well over the glass surface, and positioning was not possible. In addition, an attempt was made to peel off the entire release film 30 to expose the entire adhesive layer 23 and to bond it while adjusting the position, but the adhesive layer 23 adhered to the glass surface could not be moved, and positioning was not possible.

For this reason, the positioning and bonding were carried out using 1 liter of construction water as a lubricant and a squeegee.

(C) Results In this example, the results were similar to those of Comparative Example 1. That is, it was not possible to attach the film to the glass surface of the light-receiving window without using application water. Therefore, the positioning process, the temporary fixing process, and the attachment process were not easy, and it was necessary to apply strong pressure to remove air bubbles, so that damage to the light control film 10 was confirmed, although slight.

(Comparative Example 3)
This example also uses a release film 30 having a large coefficient of static friction with the glass surface.

(A) Process for manufacturing the light control film 100 with adhesive layer As the release film substrate 31, a polyester film with a one-sided acrylic hard coat layer having a thickness of 43 μm (PET CHC manufactured by Toppan Printing Co., Ltd.) was used, and the release agent layer coating material ₃₁₁ used in Example 1 was applied to the polyester film surface, and dried and cured at 120° C. to produce the release film 30. The thickness of the obtained release agent layer 32 was 100 nm. The reason for using a film having an acrylic hard coat layer as the release film substrate 31 was to prevent the release film 30 from being scratched during transportation from the manufacturing factory to the construction site.

In all other respects, the light control film 100 with the adhesive layer was manufactured in the same manner as in Example 1.

As in Example 1, the post-storage adhesion between the adhesive layer 23 of the resulting light-control film 100 with an adhesive layer and the blue glass surface was 0.35 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with an adhesive layer and the blue glass surface was 1.50.

(B) Construction process As in Example 1, a cut line 30x was provided at the corner of the adhesive layer-attached light-control film 100, and the release film 30 was removed to expose an end adhesive layer 23a in the shape of a right-angled isosceles triangle with a side length of 0.5 m and whose apex was the corner of the adhesive layer-attached light-control film 100.

Then, similar to Example 1, this light control film 100 with an adhesive layer was placed on the glass surface of the light-receiving window, and an attempt was made to position it by sliding it over the glass surface. However, the release film 30 did not slide well over the glass surface, and positioning was not possible. In addition, an attempt was made to peel off the entire release film 30 to expose the entire adhesive layer 23 and to bond it while adjusting the position, but the adhesive layer 23 adhered to the glass surface could not be moved, and positioning was not possible.

For this reason, the positioning and bonding were carried out using 1 liter of construction water as a lubricant and a squeegee.

(C) Results In this example, the results were similar to those of Comparative Example 1 and Comparative Example 2. That is, it was not possible to attach the film to the glass surface of the light-receiving window without using application water. For this reason, the positioning process, the temporary fixing process, and the attachment process were not easy. In addition, it was necessary to apply strong pressure to remove air bubbles, and therefore damage to the light control film 10, although slight, was confirmed.

For this reason, it was found that the static friction coefficient between the release film 30 and the blue glass surface is important in order to slide and position the adhesive layer-attached light control film 100 on the glass surface without the need for application water.

(Comparative Example 4)
This example uses an adhesive layer 23 that has a high adhesive strength to the glass surface.

(A) Step of Producing the Pressure-Sensitive Adhesive Layer-Attached Light Control Film 100 First, a release film 30 was produced in the same manner as in Example 1.

Next, 100 parts by weight of an acrylic adhesive paint (manufactured by Saiden Chemical Industries, Ltd.: OC3949) was mixed with 0.5 parts by weight of a hardener (manufactured by Saiden Chemical Industries, Ltd.: K130) and a silane coupling agent (
0.5 parts by weight of S-1 (manufactured by Saiden Chemical Co., Ltd.) was added, and the mixture was further diluted with ethyl acetate as a solvent to prepare a coating material for adhesive layer (Coating material 23 ₁ ) having a solid content of 30% by weight.

Using a comma coater, this adhesive layer coating material 23 ₁ was applied onto a 38 μm thick light release film (E7002, manufactured by Toyobo Co., Ltd.), and then dried at 100° C. for 2 minutes and further aged at 40° C. for 48 hours to form the adhesive layer 23.

Then, this adhesive layer 23 was transferred onto the release agent layer 32 surface of the release film 30.

Next, a normal mode type light control film 10 (NW001, manufactured by Toppan Printing) was attached to the surface of the adhesive layer 23 to produce an adhesive layer-attached light control film 100. This adhesive layer-attached light control film 100 has the adhesive layer 23 and release film 30 laminated in this order on one surface of the light control film 100.

Then, similarly to Example 1, the adhesion strength after storage between the adhesive layer 23 of the thus obtained light control film 100 with an adhesive layer and the blue glass surface was measured, and the adhesion strength after storage was 6.4 N/25 mm.

The static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.45.

(B) Construction process As in Example 1, a cut line 30x was provided at the corner of the adhesive layer-attached light-control film 100, and the release film 30 was removed to expose an end adhesive layer 23a in the shape of a right-angled isosceles triangle with a side length of 0.5 m and whose apex was the corner of the adhesive layer-attached light-control film 100.

Then, similar to Example 1, this light control film 100 with an adhesive layer was placed on the glass surface of the light-receiving window and slid over the glass surface to position it.

Next, when an attempt was made to temporarily attach the thus positioned light control film 100 with the adhesive layer to the glass surface with the edge adhesive layer 23a, a part of the edge adhesive layer 23a adhered strongly to the glass surface, and air bubbles were also generated between the edge adhesive layer 23a and the glass surface. This made it impossible to align the edge adhesive layer 23a and adhere it to the glass surface. Therefore, 1 liter of application water and an application squeegee were used, and the edge adhesive layer 23a was temporarily attached to the glass surface while applying strong pressure with the application squeegee to push out the air bubbles.

Finally, the remaining release film 30 was peeled off and removed, while the exposed adhesive layer 23 was adhered to the glass surface, and the entire adhesive layer-attached light control film 100 was attached to the glass surface. Note that again, 2 liters of application water and strong pressure from the application squeegee were required.

(C) Results In this example, the film could not be attached to the glass surface of the daylight window without using application water. Therefore, the positioning process, the temporary fixing process, and the attachment process were all extremely troublesome, and damage to the light control film 10 was confirmed because it was necessary to apply strong pressure to remove air bubbles.

(Comparative Example 5)
This example also uses an adhesive layer 23 that has a high adhesive strength to the glass surface.

(A) Process for manufacturing light control film 100 with adhesive layer To 100 parts by weight of acrylic adhesive paint (OC3949 manufactured by Saiden Chemical Industries, Ltd.), 0.5 parts by weight of curing agent (K130 manufactured by Saiden Chemical Industries, Ltd.), 0.5 parts by weight of silane coupling agent (S-1 manufactured by Saiden Chemical Industries, Ltd.), and 100 parts by weight of ultraviolet absorber (TINUVIN109 manufactured by BASF Japan Ltd.) were added, and the mixture was further diluted with ethyl acetate as a solvent to prepare a paint for adhesive layer (paint 23 ₂ ) with a solid content of 30% by weight.

A light control film 100 with an adhesive layer was produced in the same manner as in Comparative Example 5, except that this adhesive layer coating material ₂₃₂ was used instead of the adhesive layer coating material ₂₃₁ .

Then, similarly to Example 1, the adhesion strength after storage between the adhesive layer 23 of the thus obtained light control film 100 with an adhesive layer and the blue glass surface was measured, and the adhesion strength after storage was 3.0 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with an adhesive layer and the blue glass surface was 0.40.

(B) Application process The case where this light control film 100 with an adhesive layer was attached to the glass surface of a light-collecting window was also the same as in Comparative Example 5. That is, when the positioned light control film 100 with an adhesive layer was temporarily attached to the glass surface with its end adhesive layer 23a, a part of the end adhesive layer 23a was strongly adhered to the glass surface, and air bubbles were also generated between the end adhesive layer 23a and the glass surface. And, for this reason, in order to temporarily attach the end adhesive layer 23a to the glass surface, 1 liter of application water and strong pressure by the application squeegee were required. In addition, when peeling off and removing the remaining release film 30 and attaching the entire light control film 100 with an adhesive layer, 2 liters of application water and strong pressure by the application squeegee were required.

(C) Results In this example, the film could not be attached to the glass surface of the daylight window without using application water. Therefore, the positioning process, the temporary fixing process, and the attachment process were all extremely troublesome, and damage to the light control film 10 was confirmed because it was necessary to apply strong pressure to remove air bubbles.

(Comparative Example 6)
This example also uses an adhesive layer 23 that has a strong adhesive force with the glass surface. In this example, a thick film is used as the release film substrate 31.

(A) Step of manufacturing the light control film 100 with a pressure-sensitive adhesive layer The paint ₃₁₁ used in Example 1 was used as the paint for the release agent layer. That is, 0.1 parts by weight of a platinum-based curing agent (PL-50T, manufactured by Shin-Etsu Chemical Co., Ltd.) was added to 100 parts by weight of an addition polymerization type silicone resin (KS-841, manufactured by Shin-Etsu Chemical Co., Ltd.), and the mixture was further diluted with a mixed solvent of n-hexane and toluene to prepare paint ₃₁₁ for the release agent layer with a solid content of 5% by weight.

A polyester film (Lumirror T60, manufactured by Toray Industries, Inc.) having a thickness of 250 μm was used as the release film substrate 31, and the coating material for the release agent layer ₃₁₁ was applied to one side of the film, followed by drying and curing at 120° C. to produce the release film 30. The thickness of the resulting release agent layer 32 was 100 nm.

Next, the paint _23-1 used in Comparative Example 5 was used as the paint for the adhesive layer. That is, 0.5 parts by weight of a curing agent (K130, manufactured by Saiden Chemical Industries, Ltd.) and 0.5 parts by weight of a silane coupling agent (S-1, manufactured by Saiden Chemical Industries, Ltd.) were added to 100 parts by weight of an acrylic adhesive paint (OC3949, manufactured by Saiden Chemical Industries, Ltd.), and the mixture was further diluted with ethyl acetate as a solvent to prepare paint _23-1 for the adhesive layer having a solid content of 30% by weight.

Then, this adhesive layer coating material ₂₃₁ was applied onto a 38 μm-thick light release film (manufactured by Toyobo Co., Ltd.: E7002) to form an adhesive layer 23 .

Then, this adhesive layer 23 was transferred onto the release agent layer 32 surface of the release film 30.

Next, a normal mode type light control film 10 (NW001, manufactured by Toppan Printing) was attached to the surface of the adhesive layer 23 to produce an adhesive layer-attached light control film 100. This adhesive layer-attached light control film 100 has an adhesive layer 23 and a release film 30 laminated in this order on one surface of the light control film 100.

Then, similarly to Example 1, the adhesion strength after storage between the adhesive layer 23 of the thus obtained light control film 100 with an adhesive layer and the blue glass surface was measured, and the adhesion strength after storage was 8.9 N/25 mm.

In addition, the static friction coefficient between the release film 30 of the light control film 100 with an adhesive layer and the blue glass surface was 0.40.

(B) Construction process As in Example 1, we first tried to provide a cut line 30x at the corner of the adhesive layer-attached light-control film 100, but because the release film substrate 31 was as thick as 250 μm, it was not possible to cut it at the construction site.

For this reason, the release film 30 was completely peeled off to expose the entire adhesive layer 23, and a large amount of application water (30 liters) was used, and while adjusting the position, strong pressure was applied with a squeegee to bond it to the glass surface. The reason why such a large amount of application water is required is because the positioning and air bubbles were simultaneously performed in parallel to apply strong adhesive to a large area in one go.

(C) Results In this example, too, it was not possible to apply the film to the glass surface of the daylight window without using application water. Moreover, since the positioning and application had to be performed simultaneously, and strong adhesion had to be applied to a large area at once, the application took a long time and was extremely difficult. In addition, the damage to the light control film 10 was significant.

(Comparative Example 8)
This example also uses an adhesive layer 23 that has a strong adhesive force to the glass surface. Also in this example, a thick film is used as the release film substrate 31.

(A) Step of manufacturing the light control film 100 with adhesive layer The release film 30 was the same as the release film of Comparative Example 7. That is, 0.1 parts by weight of a platinum-based curing agent (PL-50T, manufactured by Shin-Etsu Chemical Co., Ltd.) was added to 100 parts by weight of an addition polymerization type silicone resin (KS-841, manufactured by Shin-Etsu Chemical Co., Ltd.), and a mixed solvent of n-hexane and toluene was further added to dilute the mixture, to prepare a coating material _31-1 for a release agent layer having a solid content of 5% by weight. A polyester film (Lumirror T60, manufactured by Toray Industries, Inc.) having a thickness of 250 μm was used as the release film substrate 31, and the coating material _31-1 for a release agent layer was applied to one side of the polyester film to manufacture the release film 30.

In addition, the paint 23 ₂ used in Comparative Example 6 was used as the paint for the adhesive layer. That is, 0.5 parts by weight of a curing agent (K130, manufactured by Saiden Chemical Industries, Ltd.), 0.5 parts by weight of a silane coupling agent (S-1, manufactured by Saiden Chemical Industries, Ltd.), and 100 parts by weight of an ultraviolet absorber (TINUVIN109, manufactured by BASF Japan Ltd.) were added to 100 parts by weight of an acrylic adhesive paint (OC3949, manufactured by Saiden Chemical Industries, Ltd.), and the mixture was further diluted with ethyl acetate as a solvent to prepare a paint for the adhesive layer (paint 23 ₂ ) with a solid content of 30% by weight.

Then, this adhesive layer coating material ₂₃₁ was applied onto a 38 μm-thick light release film (manufactured by Toyobo Co., Ltd.: E7002) to form an adhesive layer 23 .

Next, a normal mode type light control film 10 (NW001, manufactured by Toppan Printing Co., Ltd.) was attached to the surface of the adhesive layer 23 to produce an adhesive layer-attached light control film 100. This adhesive layer-attached light control film 100 has an adhesive layer 23 and a release film 30 laminated in this order on one surface of the light control film 100.

Then, similarly to Example 1, the adhesion strength after storage between the adhesive layer 23 of the thus obtained light control film 100 with an adhesive layer and the blue glass surface was measured, and the adhesion strength after storage was 2.5 N/25 mm.

The static friction coefficient between the release film 30 of the light control film 100 with the adhesive layer and the blue glass surface was 0.43.

(B) Construction process As in Example 1, we first tried to provide a cut line 30x at the corner of the adhesive layer-attached light-control film 100, but because the release film substrate 31 was as thick as 250 μm, it was not possible to cut it at the construction site.

For this reason, the release film 30 was completely peeled off to expose the entire adhesive layer 23, and a large amount of application water (30 liters) was used, and while adjusting the position, strong pressure was applied with a squeegee to bond it to the glass surface. The reason why such a large amount of application water is required is because the positioning and air bubbles were simultaneously performed in parallel to apply strong adhesive to a large area in one go.

(C) Results In this example, the results were the same as those in Comparative Example 7. That is, it was not possible to attach the film to the glass surface of the daylight window without using application water. Moreover, the film had to be positioned and attached at the same time, and a strong adhesive was applied over a large area at once, which took a long time and was extremely difficult to apply. Also, the damage to the light control film 10 was significant.

The above results are summarized in Table 1.

Description of the Reference Numerals 100: Light control film with adhesive layer 10: Light control film 11: Liquid crystal layer 12: Electrode film 12a: Transparent film 12b: Transparent electrode 13: Electrode film 13a: Transparent film 13b: Transparent electrode 20: Adhesive film 21: Adhesive film substrate 22: Adhesive layer 23: Adhesive layer 23: Edge adhesive layer 30: Release film 31: Release film substrate 32: Release agent layer 30x: Cut line

Claims (11)

A light-control film that changes between transparent and opaque states depending on whether or not a voltage is applied;
A pressure-sensitive adhesive layer laminated on one surface of the light-control film;
A release film that is peelably attached to the surface of the pressure-sensitive adhesive layer,
the adhesive strength when left for 30 minutes in an environment of 23° C. and 55% RH in a state where the adhesive layer is adhered to a glass surface is in the range of 0.01 to 0.41 (unit: N/25 mm);
A light control film with an adhesive layer, characterized in that the static friction coefficient between the release film and the glass surface is 0.8 or less. The light-controlling film with an adhesive layer according to claim 1, characterized in that the adhesive layer contains a thermoplastic elastomer. The light-control film with an adhesive layer according to claim 1 or 2, characterized in that the thickness of the release film is 188 μm or less. The light-control film with an adhesive layer according to any one of claims 1 to 3, characterized in that a cut line is provided for cutting off at least a partial area of the release film. The light-control film with an adhesive layer according to claim 4, characterized in that the cut line penetrates the release film. The light-control film with an adhesive layer according to claim 4, characterized in that the cut line reaches midway through the thickness direction of the release film. The light-control film with an adhesive layer according to any one of claims 1 to 3, characterized in that an embossed line is provided for cutting off at least a partial area of the release film. The light-control film with an adhesive layer according to any one of claims 4 to 7, characterized in that the cut lines or embossed lines are straight or wavy. The light-control film with an adhesive layer according to any one of claims 4 to 8, characterized in that the cut lines or embossed lines are solid lines or dashed lines. The light-control film with an adhesive layer according to any one of claims 1 to 9, characterized in that the glass is a window glass of a building or a window glass of a moving object. A method for attaching a light control film with an adhesive layer to a glass surface, comprising the steps of:
The light control film with the pressure-sensitive adhesive layer has a static friction coefficient between a release film that is peelably attached to the surface of the pressure-sensitive adhesive layer and a glass surface of 0.8 or less,
an end pressure-sensitive adhesive layer exposing step of peeling off the release film of the pressure-sensitive adhesive layer-attached light-control film at its end to expose the pressure-sensitive adhesive layer at the end;
a positioning step of sliding the light control film with the adhesive layer in a state in which the adhesive layer at the end portion is exposed by the edge adhesive layer exposing step on a glass surface to position the light control film;
a temporary fixing step of temporarily fixing the pressure-sensitive adhesive layer-attached light control film positioned in the positioning step to a glass surface;
A bonding process in which the remaining release film is peeled off from the adhesive layer-attached light control film temporarily attached in the temporary attachment process, and the exposed adhesive layer is bonded to a glass surface,
In the lamination step, the adhesive layer-attached light control film is adhered to the glass surface via the adhesive layer such that the adhesion strength when left for 30 minutes in an environment of 23° C. and 55% RH is in the range of 0.01 to 0.41 N/25 mm.
A method for attaching a light control film with an adhesive layer to a glass surface.

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