Film laminate, multilayer film, and laminate

Abstract

The present disclosure provides a film laminate, a multilayer film, and a laminate which comprise a photochromic layer having a suitable response speed and is capable of more effectively improving weather resistance.　A film laminate (FL1) according to the present disclosure comprises: an ultraviolet shielding film (10) which includes an ultraviolet shielding layer (11) that contains one or more thermoplastic resins and one or more ultraviolet shielding agents, and shields at least some of the ultraviolet light; and a photochromic film (20) which includes a photochromic layer (21) that contains a polyvinyl acetal, a plasticizer, one or more photochromic materials that each convert from a first isomer to a second isomer by means of irradiation of light in a specific wavelength range, and one or more light stabilizers. The ultraviolet shielding layer (11) transmits at least some of light in the specific wavelength range that isomerizes the photochromic materials, and has an absorbance of 1.0 or more at a wavelength of 360 nm.

Description

Film laminate, laminated film, and laminate

[0001] The present disclosure relates to a film laminate, a laminate film, and a laminate having photochromic functionality.

[0002] Laminated glass, which is made by laminating a pair of glass sheets via an adhesive layer generally called an interlayer, is resistant to breakage, and even if broken, glass fragments do not scatter. It offers excellent security and safety, and is used in a variety of applications, including vehicles and other mobile objects, buildings, and other buildings. In recent years, laminated glass has become more and more highly functional, and laminated glass with a light-adjusting function (also called light-adjusting glass) has been developed. Photochromic materials can change their molecular structure from a first isomer to a second isomer without changing their molecular weight when irradiated with light in a specific wavelength range (e.g., ultraviolet light), thereby changing their optical properties. The isomerization reaction of photochromic materials is reversible, and they can revert from the second isomer to the first isomer under specific conditions.

[0003] An interlayer containing a photochromic material whose optical properties change when exposed to ultraviolet light can change its visible light transmittance and / or color in response to the amount of ultraviolet light in sunlight. Light-controlling glass containing this interlayer is colorless and transparent or slightly colored in a state close to colorless and transparent, ensuring sufficient sunlight transmission under cloudy or rainy weather conditions with relatively low UV radiation, and becomes colored and reduces sunlight transmission under sunny weather conditions with relatively high UV radiation. This type of light-controlling glass is capable of automatic dimming in response to the amount of ultraviolet light in external light, and, unlike light-controlling glass using a polymer-dispersed liquid crystal (PDLC) film or an electrochromic (EC) device, does not require electrical means such as electrodes, making it low-cost.

[0004] JP 2018-8847 A JP 2023-75567 A U.S. Patent Application Publication No. 2013 / 286461 JP 4-358145 A

[0005] However, photochromic materials generally have poor weather resistance, and light-controllable glass using such materials tends to exhibit reduced performance when used for a long period of time in an environment exposed to sunlight containing ultraviolet rays. The optimum response speed (coloring speed and / or fading speed) of light-controllable glass also varies depending on the intended use. It is preferable to be able to adjust and optimize the response speed (coloring speed and / or fading speed) of the photochromic material depending on the intended use.

[0006] Related art to the present disclosure includes Patent Documents 1 to 4. Patent Document 1 discloses an interlayer film for laminated glass that contains a thermoplastic resin such as polyvinyl acetal, a photochromic material, and an ultraviolet absorber, and may also contain a plasticizer (claims 1 to 3). Patent Document 1 proposes using an ultraviolet absorber that, when measuring the ultraviolet transmission spectrum or absorption spectrum of a sample solution in which the ultraviolet absorber is dissolved in a specific solvent, has a transmittance of 77.0% or more at a wavelength of 365 nm and a transmittance of 80.0% or less at a wavelength of 280 nm (claim 1, paragraphs 0012 and 0013, etc.). Patent Document 2 discloses an interlayer film for laminated glass that contains a thermoplastic resin such as polyvinyl acetal and a photochromic material having a specific chemical structure, and may also contain a plasticizer (claims 1 and 2). Patent Documents 1 and 2 state that the interlayer film for laminated glass may have a single-layer structure or a multilayer structure. However, the "Examples" sections of these documents only describe the production of interlayer films for laminated glass with a single-layer structure. These documents do not disclose specific examples of manufacturing an interlayer film for laminated glass having a laminated structure including a resin layer containing an ultraviolet absorber and a resin layer containing a photochromic material, nor do they disclose that an interlayer film for laminated glass having a laminated structure including a resin layer containing an ultraviolet absorber and a resin layer containing a photochromic material has better weather resistance.

[0007] Patent Document 3 discloses an interlayer film for laminated glass comprising a thermochromic layer and a photochromic layer (Claim 1). In the "Examples" section of Patent Document 3, the thermochromic layer comprises a thermochromic material and a triazine-based UV absorber (paragraph 0020). Patent Document 4 discloses a photochromic laminate comprising a photochromic layer and a UV absorbing layer, in which the UV absorbing layer can block 30 to 90% of 350 nm light incident on the photochromic layer (Claim 1). Patent Documents 3 and 4 disclose a laminate structure of a photochromic layer and a UV absorbing layer. However, Patent Document 3 does not disclose the specific composition of the photochromic layer, and does not mention properties such as adhesion to other layers, penetration resistance, and response speed. In Patent Document 4, the UV absorbing layer blocks up to 90% of 350 nm light, which is not necessarily sufficient for applications such as window glass for moving objects such as vehicles and window glass for buildings.

[0008] The techniques disclosed in Patent Documents 1 to 4 can provide some degree of weather resistance improvement effect. However, in order to maintain good performance even when used for a long period of time as window glass for moving bodies such as vehicles and buildings under an environment where sunlight containing ultraviolet rays is irradiated, it is preferable that laminated glass including a photochromic layer has higher weather resistance.

[0009] The present disclosure has been made in consideration of the above circumstances, and aims to provide a film laminate, a laminate film, and a laminate that include a photochromic layer with a suitable response speed and can more effectively improve weather resistance.

[0010] The present disclosure provides the following film laminate, laminated film, and laminate: [1] A film laminate comprising: an ultraviolet-shielding film including an ultraviolet-shielding layer that contains one or more thermoplastic resins and one or more ultraviolet-shielding agents and that blocks at least a portion of ultraviolet light; and a photochromic film including a photochromic layer that contains polyvinyl acetal, a plasticizer, and one or more photochromic materials that convert from a first isomer to a second isomer upon irradiation with light in a specific wavelength range, wherein the ultraviolet-shielding layer transmits at least a portion of light in the specific wavelength range that isomerizes the photochromic material, and has an absorbance at a wavelength of 1.0 or greater at 360 nm.

[0011] [2] The film laminate according to [1], wherein the ultraviolet blocking layer blocks a portion of ultraviolet light, and the photochromic material is transformed from the first isomer to the second isomer upon irradiation with ultraviolet light.

[0012] [3] The film laminate of [1] or [2], wherein the ultraviolet-shielding layer contains one or more thermoplastic resins selected from the group consisting of polyvinyl acetal, ionomer, ethylene-vinyl acetate copolymer, cycloolefin polymer, polyester, and polyurethane.

[0013] [4] The film laminate according to any one of [1] to [3], wherein the photochromic layer contains one or more photochromic materials selected from the group consisting of triarylmethane compounds, stilbene compounds, azastilbene compounds, nitrone compounds, azobenzene compounds, quinone compounds, spirooxazine compounds, spironaphthoxazine compounds, hexaarylbiimidazole compounds, naphthopyran compounds, spiropyran compounds, fulgide compounds, diarylethene compounds, and inorganic photochromic materials.

[0014] [5] The film laminate of any one of [1] to [4], wherein the photochromic layer contains one or more T-type photochromic materials. [6] The film laminate of any one of [1] to [5], wherein the photochromic layer contains one or more light stabilizers. [7] The film laminate of [6], wherein the light stabilizer contains one or more hindered amine light stabilizers.

[0015] [8] The film laminate according to any one of [1] to [7], wherein the ultraviolet ray blocking layer has an absorbance of 3.0 or less at a wavelength of 380 nm and an absorbance of 1.0 or less at a wavelength of 400 nm.

[0016] [9] The film laminate of any one of [1] to [8], further comprising a separator layer between the ultraviolet blocking layer and the photochromic layer, the separator layer preventing migration of the ultraviolet blocking agent into the photochromic layer and migration of the photochromic material into the ultraviolet blocking layer.

[10] The film laminate of [9], wherein the separator layer contains one or more materials selected from the group consisting of polyester, polyvinyl alcohol, polycarbonate, polyvinyl acetal, ionomer, methacrylic resin, polyolefin, polyimide, and inorganic materials.

[0017]

[11] The film laminate of any one of [1] to

[10] , further comprising a colored layer on the opposite side of the photochromic layer from the ultraviolet-shielding layer.

[12] The film laminate of any one of [1] to

[11] , further comprising an infrared-shielding layer that blocks at least a portion of infrared rays.

[0018]

[13] A film laminate according to any one of [1] to

[12] , wherein when the visible light transmittance (Tlv) of the film laminate before UV irradiation and the visible light transmittance (Tdv) of the film laminate after UV irradiation are determined by the following method, the following formula (I) is satisfied: 1.5≦Tlv / Tdv≦20 (I) [Measurement Method] The transmission spectrum of the film laminate before UV irradiation is measured using a spectrophotometer under conditions of a measurement temperature of 23°C, a measurement wavelength range of 380 to 780 nm, and a scan speed of 1200 nm / min. From the obtained transmission spectrum, the visible light transmittance (Tlv) is determined in accordance with JIS R3212:2015 and JIS Z8722:2009. Next, the photochromic layer included in the film laminate is irradiated with simulated sunlight containing UV light from the UV-shielding layer side at an intensity of 1 sun for 60 seconds. 20 seconds after the end of the ultraviolet irradiation, the transmission spectrum of the film laminate after ultraviolet irradiation is measured in the same manner as before ultraviolet irradiation to determine the visible light transmittance (Tdv).

[0019]

[14] A laminate film comprising: an ultraviolet-shielding layer containing one or more thermoplastic resins and one or more ultraviolet-shielding agents and shielding at least a portion of ultraviolet light; and a photochromic layer containing polyvinyl acetal, a plasticizer, and one or more photochromic materials that are converted from a first isomer to a second isomer upon irradiation with light in a specific wavelength range, wherein the ultraviolet-shielding layer transmits at least a portion of the light in the specific wavelength range that isomerizes the photochromic material, and has an absorbance at a wavelength of 1.0 or more at a wavelength of 360 nm.

[15] A laminate comprising the laminate film of

[14] and a pair of translucent substrates that sandwich the laminate film.

[0020] According to the present disclosure, it is possible to provide a film laminate, a laminated film, and a laminate that include a photochromic layer with a favorable response speed and can more effectively improve weather resistance.

[0021] 1 is a schematic cross-sectional view of a film laminate of a first embodiment according to the present invention. 2 is a schematic cross-sectional view of a film laminate of a second embodiment according to the present invention. 3 is a schematic cross-sectional view of a film laminate of a third embodiment according to the present invention. 4 is a schematic cross-sectional view of a laminate of a first embodiment according to the present invention. 5 is a schematic cross-sectional view of a laminate of a second embodiment according to the present invention. 6 is an example of the absorption spectra of an ultraviolet-shielding film alone and a glass plate alone. 7 is a transmission spectrum of a laminated glass (glass laminate) obtained in Example (E1) (transparent state and colored state before a weather resistance test, and transparent state and colored state after a weather resistance test). 8 is a transmission spectrum of a laminated glass (glass laminate) obtained in Example (E4) (transparent state and colored state before a weather resistance test, and transparent state and colored state after a weather resistance test). 9 is a transmission spectrum of a laminated glass (glass laminate) obtained in Comparative Example (EC2) (transparent state and colored state before a weather resistance test, and transparent state and colored state after a weather resistance test). 1 is a graph showing discoloration changes at the maximum absorption wavelength (580 m) of the laminated glasses (glass laminates) obtained in Examples (E1) and (E12).

[0022] Generally, the terms "film" and "sheet" are used for thin film molded bodies depending on the thickness. Therefore, "film" as used herein may include "sheet," and "sheet" as used herein may include "film." In this specification, (meth)acrylic is a general term for acrylic and methacrylic. Unless otherwise specified, in this specification, ultraviolet light is light in the wavelength range of 300 to 380 nm, infrared light is light in the wavelength range of 780 to 2500 nm, and visible light is light in the wavelength range of 380 to 780 nm. Unless otherwise specified, in this specification, optical properties such as absorbance and transmittance are properties at room temperature (20 to 25°C).

[0023] [Film Laminate] The film laminate of the present disclosure includes an ultraviolet ray shielding film including an ultraviolet ray shielding layer that contains one or more thermoplastic resins and one or more ultraviolet ray shielding agents and that shields at least a portion of ultraviolet rays, and a photochromic film that includes a photochromic layer that contains one or more polyvinyl acetals, one or more plasticizers, and one or more photochromic materials that are converted from a first isomer to a second isomer upon irradiation with light in a specific wavelength range.

[0024] The ultraviolet blocking layer may have a single layer structure or a laminate structure. The ultraviolet blocking layer may contain one or more plasticizers as needed. The ultraviolet blocking layer may contain one or more other additives as needed. The ultraviolet blocking film may include one or more optional layers other than the ultraviolet blocking layer. The photochromic layer may have a single layer structure or a laminate structure. The photochromic layer may contain one or more other additives as needed. The photochromic film may include one or more optional layers other than the photochromic layer.

[0025] When irradiated with light in a specific wavelength range (e.g., ultraviolet light), the molecular structure of a photochromic material changes from a first isomer to a second isomer without changing its molecular weight, thereby changing its optical properties. In the film laminate of the present disclosure, the ultraviolet-blocking layer transmits at least a portion of the light in the specific wavelength range that isomerizes the photochromic material from the first isomer to the second isomer. In the film laminate of the present disclosure, the ultraviolet-blocking layer blocks at least a portion of ultraviolet light and has an absorbance of 1.0 or greater at a wavelength of 360 nm. In a preferred embodiment, the ultraviolet-blocking layer blocks a portion of ultraviolet light, and the photochromic material can be converted from the first isomer to the second isomer by ultraviolet irradiation. The light that isomerizes the photochromic material from the first isomer to the second isomer can be natural light (sunlight) or artificial light emitted from a light-emitting means such as a light source and a lighting device.

[0026] The isomerization reaction of a photochromic material is reversible, and under certain conditions, for example, by irradiation with light in a specific wavelength range and / or heat, the second isomer can be converted back to the first isomer. The light that can isomerize the photochromic material from the second isomer to the first isomer can be natural light (sunlight) or artificial light emitted from a light source, lighting device, or other light-emitting means. The heat that can isomerize the photochromic material from the second isomer to the first isomer can be heat in a room temperature environment (20 to 30°C), heat at a temperature below room temperature, or heat at a temperature above room temperature.

[0027] In the present disclosure, a photochromic material is contained in a thermoplastic resin composition containing polyvinyl acetal and a plasticizer. A photochromic layer containing polyvinyl acetal, a plasticizer, and a photochromic material has excellent adhesion to a light-transmitting substrate such as glass and / or other layers, and can also have functions such as penetration resistance and sound insulation. The preferred response speed (coloring speed and / or fading speed) of light-controlling glass varies depending on the application. In a photochromic layer containing an appropriate amount of plasticizer, even if the type and content of the photochromic material are the same, the response speed (coloring speed and / or fading speed) of the photochromic material can be changed by adjusting the type and / or amount of the plasticizer. In the film laminate of the present disclosure, the response speed (coloring speed and / or fading speed) of the photochromic material can be easily adjusted or designed depending on the application. Therefore, the present disclosure can provide a film laminate with a suitable response speed (coloring speed and / or fading speed) of the photochromic layer.

[0028] FIG. 1 shows a schematic cross-sectional view of a film laminate according to a first embodiment of the present invention. In the figure, reference numeral FL1 denotes a film laminate, reference numeral 10 denotes an ultraviolet-shielding film, and reference numeral 20 denotes a photochromic film. The ultraviolet-shielding film 10 is a film of a single-layer structure or a laminate structure that includes one or more ultraviolet-shielding layers 11 and may optionally include one or more other layers. The photochromic film 20 is a film of a single-layer structure or a laminate structure that includes one or more photochromic layers 21 and may optionally include one or more other layers.

[0029] The method for producing the ultraviolet shielding film and the photochromic film is not particularly limited, and examples thereof include an extrusion method, a calendar method, a press method, a casting method, and an inflation method. Among these, an extrusion method using an extruder equipped with a T-die (also called a T-die method) is preferred.

[0030] The T-die method will be described below. A resin material for an ultraviolet shielding film (specifically, a resin material containing one or more thermoplastic resins (such as polyvinyl acetal and ionomer); one or more ultraviolet absorbers; optionally one or more plasticizers; and optionally one or more other additives) or a resin material for a photochromic film (specifically, a resin material containing one or more polyvinyl acetals; one or more photochromic materials; one or more plasticizers; and optionally one or more other additives) is melt-kneaded using an extruder and extruded in a molten state from a T-die having a wide discharge opening.

[0031] To remove foreign matter, the molten resin is preferably melt-filtered using a filter before extrusion. By forming a film using the melt-filtered molten resin, a film with fewer defects caused by foreign matter and gels can be obtained. Examples of extruders include single-screw extruders, twin-screw extruders, multi-screw extruders, and combinations thereof. The resin temperature during extrusion is not particularly limited, and when the thermoplastic resin is polyvinyl acetal, it is preferably 150 to 250°C, more preferably 170 to 230°C. The molten resin extruded into a film form from a T-die is cooled using multiple cooling rolls, and the film obtained after cooling is taken up by a take-up roll. The above extrusion, cooling, and take-up steps are carried out continuously.

[0032] Examples of methods for producing the film laminate FL1 include a method of overlapping an ultraviolet-shielding film and a photochromic film; a method of thermocompressing the temporary laminate obtained by this method; a method of applying a resin solution containing a thermoplastic resin, a photochromic material, and a solvent onto the ultraviolet-shielding film and then drying and removing the solvent; and a method of applying a resin solution containing a thermoplastic resin, an ultraviolet-shielding material, and a solvent onto the photochromic film and then drying and removing the solvent.

[0033] The film laminate FL1 includes a temporary laminate before thermocompression bonding in which an ultraviolet-shielding film and a photochromic film are superimposed; a thermocompression-bonded body obtained by thermocompression bonding this temporary laminate; a laminate of an ultraviolet-shielding film and a coated and dried product of a resin solution containing a thermoplastic resin and a photochromic material; and a laminate of a photochromic film and a coated and dried product of a resin solution containing a thermoplastic resin and an ultraviolet-shielding agent.

[0034] In the film laminate of the above embodiment in which the ultraviolet blocking layer and the photochromic layer are in contact with each other, interlayer migration of the ultraviolet blocking agent and / or the photochromic material may occur. In particular, interlayer migration of the ultraviolet blocking agent and / or the photochromic material may occur along with interlayer migration of the plasticizer contained in the photochromic layer and / or the plasticizer that may be contained in the ultraviolet blocking layer.

[0035] The film laminate of the present disclosure may have a separator layer (also referred to as a blocking layer) between the UV-blocking layer and the photochromic layer, which prevents the UV-blocking agent in the UV-blocking layer from migrating into the photochromic layer and prevents the photochromic material in the photochromic layer from migrating into the UV-blocking layer. The separator layer transmits at least a portion of light in a specific wavelength range that isomerizes the photochromic material from a first isomer to a second isomer. The separator layer may have a single-layer structure or a laminate structure.

[0036] FIG. 2 shows a schematic cross-sectional view of a film laminate according to a second embodiment of the present invention. The same components as those in FIG. 1 are designated by the same reference numerals, and their descriptions are omitted. In the figure, reference numerals FL2, FL2A, and FL2C denote film laminates, reference numeral 30 denotes a separator film, and reference numeral 31 denotes a separator layer. The film laminate FL2 of the second embodiment has a separator layer 31 between the ultraviolet-shielding layer 11 and the photochromic layer 21. The film laminate FL2A, which is a first embodiment, has a separator film 30 including a separator layer 31 between the ultraviolet-shielding film 10 and the photochromic film 20. The separator film 30 may include one or more other layers as necessary. The separator layer 31 may be a layer included in the ultraviolet-shielding film 10 and / or the photochromic film 20. In the film laminate FL2B, which is a second embodiment, the ultraviolet-shielding film 10 includes the ultraviolet-shielding layer 11 and the separator layer 31. In the film laminate FL2C of the third embodiment, the photochromic film 20 includes a photochromic layer 21 and a separator layer 31.

[0037] Examples of methods for producing the film laminate FL2A include a method of overlapping an ultraviolet-shielding film, a separator film, and a photochromic film; a method of thermocompressing a temporary laminate obtained by this method; a method of overlapping a separator film on an ultraviolet-shielding film, applying a resin solution containing a thermoplastic resin, a photochromic material, and a solvent, and then drying and removing the solvent; and a method of overlapping a separator film on a photochromic film, applying a resin solution containing a thermoplastic resin, an ultraviolet-shielding material, and a solvent, and then drying and removing the solvent.

[0038] Examples of methods for producing the film laminate FL2B include a method of overlapping an ultraviolet-shielding film containing an ultraviolet-shielding layer and a separator layer with a photochromic film; a method of thermocompression bonding a temporary laminate obtained by this method; and a method of applying a resin solution containing a thermoplastic resin, a photochromic material, and a solvent onto an ultraviolet-shielding film containing an ultraviolet-shielding layer and a separator layer, and then drying and removing the solvent.

[0039] Examples of methods for producing the film laminate FL2C include a method of overlapping an ultraviolet-shielding film with a photochromic film containing a photochromic layer and a separator layer; a method of thermocompressing the temporary laminate obtained by this method; and a method of applying a resin solution containing a thermoplastic resin, an ultraviolet-shielding agent, and a solvent onto a photochromic film containing a photochromic layer and a separator layer, and then drying and removing the solvent.

[0040] Examples of methods for producing an ultraviolet shielding film containing an ultraviolet shielding layer and a separator layer include a method of thermocompression bonding an ultraviolet shielding film containing an ultraviolet shielding layer and a separator film containing a separator layer; a method of forming a separator layer on an ultraviolet shielding film containing an ultraviolet shielding layer by a known method such as a liquid phase method or a gas phase method; and a method of applying a resin solution containing a thermoplastic resin, an ultraviolet shielding agent, and a solvent onto a separator film containing a separator layer, and then drying and removing the solvent.

[0041] Examples of methods for producing a photochromic film containing a photochromic layer and a separator layer include a method of thermocompression bonding a photochromic film containing a photochromic layer and a separator film containing a separator layer together; a method of forming a separator layer on a photochromic film containing a photochromic layer by a known method such as a liquid phase method or a gas phase method; and a method of applying a resin solution containing a thermoplastic resin, a photochromic material, and a solvent onto a separator film containing a separator layer, and then drying and removing the solvent.

[0042] By providing a separator layer between the ultraviolet-shielding layer and the photochromic layer, interlayer migration of the plasticizer and interlayer migration of the ultraviolet-shielding agent and / or photochromic material are suppressed, allowing each of the ultraviolet-shielding layer and the photochromic layer to stably exhibit the desired functions. When the film laminate is left standing at 25°C and atmospheric pressure for 24 hours, the separator layer preferably has a transmittance of 0 to 10% for the plasticizer containing the ultraviolet-shielding agent or photochromic material. The upper limit is more preferably 5%, even more preferably 1%, even more preferably 0.5%, even more preferably 0.1%, particularly preferably 0.05%, and most preferably 0.01%.

[0043] The film laminate of the present disclosure may further include a coloring layer on the side of the photochromic layer opposite the UV-blocking layer. The coloring layer may include one or more thermoplastic resins and one or more colorants. Preferred embodiments of the type and content of the thermoplastic resin that can be included in the coloring layer are the same as those of the thermoplastic resin that can be included in the UV-blocking layer. Examples of colorants include dyes, pigments, dyes, and luminescent materials, and known colorants can be used. The color of the coloring layer is not particularly limited, and from the standpoint of design, a neutral color such as gray is preferred for automotive applications. The coloring layer can adjust the visible light transmittance (brightness) of the film laminate. A lower visible light transmittance of the coloring layer is advantageous because it reduces the color difference ΔE (the difference between the color in the initial colored state and the color in the colored state after deterioration) when the photochromic material deteriorates and the coloring performance decreases. The visible light transmittance of the colored layer is not particularly limited, and from the viewpoint of the balance between the manifestation of the dimming effect of the photochromic material and the above-mentioned effect (the effect of reducing the color difference ΔE), it is preferably 4 to 90% for applications such as vehicle sunroofs. The lower limit is more preferably 5%. The upper limit is more preferably 80%, even more preferably 70%, even more preferably 60%, even more preferably 50%, even more preferably 40%, even more preferably 30%, particularly preferably 20%, and most preferably 10%. In order to prevent interlayer migration of the photochromic material and / or colorant, a separator layer may be provided between the photochromic layer and the colored layer.

[0044] Figure 3 shows a schematic cross-sectional view of a film laminate according to a third embodiment of the present invention. The same components as those in Figure 1 are designated by the same reference numerals, and a description thereof will be omitted. In the figure, reference numerals FL3, FL3A, and FL3B denote film laminates, and reference numeral 41 denotes a colored layer. The film laminate FL3 of the third embodiment has an ultraviolet-shielding layer 11, a photochromic layer 21, and a colored layer 41. In the film laminate FL3A of the first embodiment, the colored layer 41 is made of a colored film 40 separate from the photochromic film 20. In the film laminate FL3B of the second embodiment, the colored layer 41 is a layer included in the photochromic film 20.

[0045] 2, a colored layer 41 may be provided on the side of the photochromic layer 21 opposite to the ultraviolet-shielding layer 11 (the lower side in the figure). In such a design modification example, the colored layer 41 may be made of a colored film 40 separate from the photochromic film 20, or may be a layer included in the photochromic film 20.

[0046] (Other Functions or Other Functional Layers) In the film laminate of the present disclosure, the ultraviolet-shielding layer may have a function other than the ultraviolet-shielding function. The photochromic layer may have a function other than the photochromic function. The separator layer that may be optionally included in the film laminate of the present disclosure may have a function other than the function of suppressing interlayer migration of additives. The colored layer that may be optionally included in the film laminate of the present disclosure may have a function other than coloring. The film laminate of the present disclosure may have one or more other functional layers in addition to the ultraviolet-shielding layer, photochromic layer, separator layer, and colored layer. In the film laminate of the present disclosure, other functions that the ultraviolet-shielding layer, photochromic layer, separator layer, colored layer, and other functional layers may have include an infrared-shielding function, a function containing a material with low thermal conductivity to prevent heat propagation, a sound-insulating function, a light-emitting function such as a fluorescent function, an electrochromic function, a thermochromic function, a hologram function, a function of improving adhesion between the film laminate of the present disclosure and a light-transmitting substrate, and a design function.

[0047] The film laminate of the present disclosure may, for example, include an infrared-shielding layer that blocks at least a portion of infrared rays. The ultraviolet-shielding layer and / or the photochromic layer may contain one or more infrared-shielding agents and may also function as an infrared-shielding layer. The separator layer may contain one or more infrared-shielding agents or be made of an infrared-shielding film and may also function as an infrared-shielding layer. The other functional layer may contain one or more infrared-shielding agents or be made of an infrared-shielding film and may function as an infrared-shielding layer. The infrared-shielding agent may be either an infrared-absorbing type or an infrared-reflecting type, with an infrared-reflecting type being preferred.

[0048] [Laminate Film] The laminate film of the present disclosure includes an ultraviolet-shielding layer containing one or more thermoplastic resins and one or more ultraviolet-shielding agents and capable of blocking at least a portion of ultraviolet light; and a photochromic layer containing one or more polyvinyl acetals, one or more plasticizers, and one or more photochromic materials that convert from a first isomer to a second isomer upon irradiation with light in a specific wavelength range. In the laminate film of the present disclosure, the ultraviolet-shielding layer transmits at least a portion of light in a specific wavelength range that isomerizes the photochromic material and has an absorbance of 1.0 or greater at a wavelength of 360 nm. The laminate film of the present disclosure may include a separator layer (blocking layer) between the ultraviolet-shielding layer and the photochromic layer, which prevents the ultraviolet-shielding agent in the ultraviolet-shielding layer from migrating into the photochromic layer and prevents the photochromic material in the photochromic layer from migrating into the ultraviolet-shielding layer. The laminate film of the present disclosure may further include a coloring layer on the side of the photochromic layer opposite the ultraviolet-shielding layer. The laminate film of the present disclosure may include one or more optional layers other than the ultraviolet-shielding layer, the photochromic layer, the separator layer, and the colored layer. Preferred aspects of the ultraviolet-shielding layer and the photochromic layer are the same as those layers included in the film laminate of the present disclosure described above. Preferred aspects of the separator layer are the same as those that can be included in the film laminate of the present disclosure described above. Preferred aspects of the colored layer are the same as those that can be included in the film laminate of the present disclosure described above. One aspect of the laminate film of the present disclosure is a laminated glass interlayer.

[0049] [Laminate] The laminate of the present disclosure includes the laminate film of the present disclosure and a pair of light-transmitting substrates that sandwich the laminate film. One embodiment of the laminate of the present disclosure is laminated glass.

[0050] 4A and 4B are schematic cross-sectional views of laminates according to first and second embodiments of the present invention. In these figures, the same components as those in FIGS. 1 and 2 are designated by the same reference numerals, and their descriptions are omitted. In the figures, reference numerals LB1 and LB2 denote laminates, reference numerals LM1 and LM2 denote laminate films (interlayer films), and reference numerals 51 and 52 denote translucent substrates. The laminate LB1 of the first embodiment includes a laminate film LM1 including an ultraviolet-shielding layer 11 and a photochromic layer 21, and a pair of translucent substrates 51 and 52 sandwiching the laminate film LM1. The laminate LB2 of the second embodiment includes a laminate film LM2 including an ultraviolet-shielding layer 11, a separator layer 31, and a photochromic layer 21, and a pair of translucent substrates 51 and 52 sandwiching the laminate film LM2.

[0051] The laminate of the present disclosure can be produced by stacking multiple components including a first light-transmitting substrate, the film laminate of the present disclosure, and a second light-transmitting substrate to obtain a temporary laminate, which is then thermocompressed. The thermocompression bonding process can be carried out in one or more stages, and preferably includes a preliminary compression bonding process in which the temporary laminate is heated at a temperature of 90 to 110°C to obtain a preliminary compression bond, and a main compression bonding process in which the preliminary compression bond is pressurized and heated at a higher temperature. Preliminary compression bonding methods include, from the viewpoints of degassing properties and inter-component bonding, methods of degassing under reduced pressure, such as the vacuum bag method, vacuum ring method, and vacuum laminator method; methods of degassing using nip rolls; and methods of compression at high temperatures. Among these, methods of degassing under reduced pressure are preferred. For details of the vacuum bag method and the vacuum ring method, see British Patent No. 1235683. The vacuum laminator may include a chamber that can be heated and evacuated. The absolute pressure in the preliminary pressure-bonding step is preferably 10 to 30 kPa. The heating time is preferably 10 to 60 minutes, more preferably 20 to 60 minutes. In the main pressure-bonding step, for example, the obtained pre-pressure-bonded body is placed in an autoclave and heated under pressure at a pressure of 1.0 to 1.5 MPa and at a temperature higher than the heating temperature in the preliminary pressure-bonding step. The heating temperature is preferably 110 to 150°C. The lower limit is more preferably 120°C. The heating time is preferably 20 to 40 minutes.

[0052] The film laminate, laminate film, and laminate of the present disclosure include a laminate structure (also referred to as the laminate structure of the present disclosure) including an ultraviolet-shielding layer and a photochromic layer. In the film laminate, laminate film, and laminate of the present disclosure, the ultraviolet-shielding layer and the photochromic layer can be arranged so that light containing light (e.g., ultraviolet light) in a specific wavelength range that isomerizes the photochromic material from a first isomer to a second isomer is incident on the photochromic layer from the ultraviolet-shielding layer side. When the light containing light (e.g., ultraviolet light) in a specific wavelength range that isomerizes the photochromic material from the first isomer to the second isomer is sunlight, the ultraviolet-shielding layer is arranged on the outside (external environment side) and the photochromic layer is arranged on the inside (internal environment side, specifically, the interior or interior of a vehicle, etc.).

[0053] In the film laminate, laminate film, and laminate of the present disclosure, the UV-blocking layer transmits at least a portion of light in a specific wavelength range necessary for isomerization of a photochromic material from a first isomer to a second isomer, while blocking at least a portion of UV rays that may have adverse effects on the photochromic material, such as degradation and decomposition. For example, the photochromic material can be converted from the first isomer to the second isomer by UV irradiation. In this case, the UV-blocking layer transmits UV rays in a specific wavelength range with the energy required for isomerization of the photochromic material, while blocking at least a portion of UV rays (particularly UV rays in the short wavelength range (e.g., 360 nm or shorter)) that may have adverse effects on the photochromic material, such as degradation and decomposition.

[0054] Compared to a single-layer structure in which an ultraviolet blocking agent is added to the photochromic layer, the laminate structure of the present disclosure can reliably block at least a portion of ultraviolet light by the ultraviolet blocking layer before it enters the photochromic layer, effectively suppressing deterioration of the photochromic material due to excessive ultraviolet light exposure. Furthermore, because the ultraviolet blocking layer and the photochromic layer are independent of each other, the laminate structure of the present disclosure can effectively reduce the impact on the photochromic material of radicals that may be generated by the reaction between the ultraviolet blocking agent and ultraviolet light, compared to a single-layer structure in which an ultraviolet blocking agent is added to the photochromic layer. The film laminate, laminate film, and laminate of the present disclosure combine the above-mentioned effects to effectively improve weather resistance.

[0055] The ultraviolet-shielding layer preferably blocks at least a portion of ultraviolet light in the short wavelength range (e.g., 360 nm or less), which may have adverse effects on the photochromic material, such as deterioration and decomposition. Specifically, the ultraviolet-shielding layer preferably has an absorbance of 1.0 or more at a wavelength of 360 nm. The lower limit is more preferably 1.2, even more preferably 1.5, even more preferably 1.8, even more preferably 2.0, particularly preferably 2.5, and most preferably 3.0. The upper limit is not particularly limited and can be, for example, 5.0 or 4.0.

[0056] When the photochromic material is one that converts from a first isomer to a second isomer upon irradiation with ultraviolet light, the ultraviolet-shielding layer preferably transmits at least a portion of ultraviolet light in the long wavelength region (e.g., 370 to 380 nm), which is necessary for isomerization of the photochromic material from the first isomer to the second isomer and is relatively unlikely to have adverse effects on the photochromic material, such as deterioration and decomposition. Specifically, the ultraviolet-shielding layer preferably has an absorbance of 3.0 or less at a wavelength of 380 nm. The upper limit is more preferably 2.5, even more preferably 2.0, even more preferably 1.8, even more preferably 1.5, even more preferably 1.2, particularly preferably 1.0, and most preferably 0.8. The lower limit is not particularly limited and can be, for example, 0.1 or 0.2.

[0057] The ultraviolet-shielding layer also preferably has good transmittance of visible light, which is unlikely to have adverse effects such as deterioration and decomposition on the photochromic material. Specifically, the ultraviolet-shielding layer preferably has an absorbance of 1.0 or less at a wavelength of 400 nm. The upper limit is more preferably 0.8, even more preferably 0.5, even more preferably 0.3, even more preferably 0.2, particularly preferably 0.15, and most preferably 0.1. The lower limit is not particularly limited and can be, for example, 0.01.

[0058] (Ultraviolet Shielding Agent) One or more known ultraviolet shielding agents can be used as the ultraviolet shielding agent contained in the ultraviolet shielding layer. The ultraviolet shielding agent may be either an ultraviolet absorbing type or an ultraviolet reflecting type, with an ultraviolet absorbing type being preferred. Examples of the ultraviolet absorber include a benzophenone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, a triazine-based ultraviolet absorber, a benzodithiol-based ultraviolet absorber, an azomethine-based ultraviolet absorber, and an indole-based ultraviolet absorber. A thermochromic material whose absorbance increases with increasing temperature may also be used as the ultraviolet shielding agent.

[0059] Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone (e.g., "SEESORB100" manufactured by Shipro Chemical Co., Ltd.), 2-hydroxy-4-methoxybenzophenone (e.g., "SEESORB101" manufactured by Shipro Chemical Co., Ltd.), 2-hydroxy-4-octyloxybenzophenone (e.g., "SEESORB102" manufactured by Shipro Chemical Co., Ltd.), 4-dodecyloxy-2-hydroxybenzophenone (e.g., "SEESORB103" manufactured by Shipro Chemical Co., Ltd.), 2-hydroxy-4-(octyloxy)benzophenone (e.g., "ADEKA STAB 1413" manufactured by ADEKA Corporation), 2,2',4,4'-tetrahydroxybenzophenone (e.g., "SEESORB106" manufactured by Shipro Chemical Co., Ltd.), and other benzophenone-based ultraviolet absorbers (e.g., "ADEKA STAB 1413" manufactured by ADEKA Corporation).

[0060] Examples of benzotriazole-based ultraviolet absorbers include 2-(2H-benzotriazol-2-yl)-4-tert-butylphenol (e.g., "Eversorb 70" manufactured by Everlight Chemical Co.), 2-(3'-t-butyl-2'-hydroxy-5'-benzotriazole)-5-chlorobenzotriazole (e.g., "Eversorb 73" manufactured by Everlight Chemical Co.), 2-(2'-hydroxy-3',5'-di-tert-amylphenyl)benzotriazole (e.g., "Eversorb 74" manufactured by Everlight Chemical Co.), and 2-[2'-hydroxy-3,5-di(1,1-dimethylbenzyl)phenyl]-2H-benzotriazole (e.g., "Eversorb 75" manufactured by Everlight Chemical Co.), 76"), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (e.g., "ADEKA STAB LA-29" manufactured by ADEKA Corporation), 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol] (e.g., "ADEKA STAB LA-31" manufactured by ADEKA Corporation), 2-(2H-benzotriazol-2-yl)-p-cresol (e.g., "ADEKA STAB LA-32" manufactured by ADEKA Corporation), 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chloro-benzotriazole (e.g., "Eversorb 75" manufactured by Everlight Chemical Co.), a mixture of octyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate and 2-ethylhexyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate (e.g., "Eversorb 109" manufactured by Everlight Chemical Co.), other benzotriazole-based ultraviolet absorbers (e.g., "Eversorb 77", "Eversorb 79", "Eversorb 88", "Eversorb 89", BASF's "Tinuvin 326" and "Tinuvin 571", Daiwa Chemical Industries, Ltd.'s "DAINSORB T-7", "DAINSORB T-0", "DAINSORB T-52", and "DAINSORB T-53", Shipro Chemical Industries, Ltd.'s "SEESORB 701", etc.

[0061] Examples of triazine-based ultraviolet absorbers include 2,4-bis(2,4-dibenzotriazole)-6-(2-hydroxy-4-n-octyloxyphenyl)-1,3,5-triazine (e.g., "CYASORB UV-1164" manufactured by Sun Chemical Co.), 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol (e.g., "ADEKA STAB LA-46" manufactured by ADEKA Corporation), and a mixture of a reaction product (85%) of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl with oxirane [(C10-C16 alkyloxy)methyl]oxirane and 1-methoxy-2-propanol (15%) (e.g., "Tinuvin" manufactured by BASF). 400"), reaction products of 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine and (2-ethylhexyl)-glycidic acid ester (for example, "Tinuvin 405" manufactured by BASF), 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3-5-triazine (for example, "Tinuvin 460" manufactured by BASF), and other triazine-based ultraviolet absorbers (for example, "Tinuvin 477", "Tinuvin 479", and "Tinuvin 1600" manufactured by BASF).

[0062] Other ultraviolet absorbers include bis-(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, methyl-(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate (e.g., "Eversorb 93" manufactured by Everlight Chemical Co.), decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl)ester, reaction products of 1,1-dimethylethyl hydroperoxide and octane (e.g., "Eversorb 95" manufactured by Everlight Chemical Co.), and "Hostavin VSU" manufactured by CLARIANT.

[0063] Among the above, benzotriazole-based ultraviolet absorbers (e.g., Tinuvin 326, etc.) and triazine-based ultraviolet absorbers (e.g., Tinuvin 479, etc.) are preferred, and triazine-based ultraviolet absorbers (e.g., Tinuvin 479, etc.) are more preferred, because they make it easier to obtain an ultraviolet-shielding layer having absorbances within preferred ranges at 360 nm, 380 nm, and 400 nm, and the laminate structure of the present disclosure is more likely to achieve both weather resistance and photochromic performance.

[0064] The content of the ultraviolet blocking agent in the ultraviolet blocking layer (the total amount if multiple types are used, unless otherwise specified) is not particularly limited and can be determined so that the absorbance at 360 nm, 380 nm, and 400 nm falls within a preferred range depending on the type of ultraviolet blocking agent and the thickness of the ultraviolet blocking layer. The content of the ultraviolet blocking agent in the ultraviolet blocking layer is preferably 0.01 to 5 parts by mass relative to 100 parts by mass of the total of the thermoplastic resin and the plasticizer. The lower limit is more preferably 0.05 parts by mass, particularly preferably 0.1 parts by mass, and most preferably 0.15 parts by mass. The upper limit is more preferably 4 parts by mass, even more preferably 3 parts by mass, even more preferably 2 parts by mass, particularly preferably 1 part by mass, and most preferably 0.8 parts by mass.

[0065] (Photochromic Material) As the photochromic material contained in the photochromic layer, one or more known photochromic materials can be used. The photochromic layer preferably contains one or more photochromic materials selected from the group consisting of triarylmethane compounds, stilbene compounds, azastilbene compounds, nitrone compounds, azobenzene compounds, quinone compounds, spirooxazine compounds, spironaphthoxazine compounds, hexaarylbiimidazole compounds, naphthopyran compounds, spiropyran compounds, fulgide compounds, diarylethene compounds, and inorganic photochromic materials.

[0066] Examples of photochromic materials include 4-[bis(9,9-dimethylfluoren-2-yl)amino]azobenzene, 1,2,3,4,5,6-hexa-O-[11-[4-(4-hexylphenylazo)phenoxy]undecanoyl]-D-mannitol, 4,4'-bis(hexyloxy)-3-methylazobenzene, 4,4'-bis(docyloxy)-3-methylazobenzene, 4,4'-bis(dodecyloxy)-3-methylazobenzene, 1,2-bis(2,4-dimethyl-5-phenyl-3-thienyl)-3,3,4,4,5,5-hexa-D-mannitol, 4,4'-bis(hexyloxy)-3-methylazobenzene, 4,4'-bis(docyloxy)-3-methylazobenzene, 4,4'-bis(dodecyloxy)-3-methylazobenzene, and 1,2-bis(2,4-dimethyl-5-phenyl-3-thienyl)-3,3,4,4,5,5-hexa-D-mannitol. 2,3-bis(2,4,5-trimethyl-3-thienyl)maleic anhydride, ... amide, 1,2-bis[2-methylbenzo[b]thiophen-3-yl]-3,3,4,4,5,5-hexafluoro-1-cyclopentene, 1',3'-dihydro-8-methoxy-1',3',3'-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2'-[2H]indole], 1,3,3-trimethylindolinobenzopyrilospiran, 1,3,3-trimethylindolino-6'-nitrobenzopyrilospiran, 1,3,3-trimethylindolino-6'-bromobenzopyrilospiran, 1,3,3-trimethylindolino- Examples include 8'-methoxybenzopyrilospiran, 1,3,3-trimethylindolino-β-naphthopyrilospiran, 1,3,3-trimethylindolinonaphthospirooxazine, 1-(2-hydroxyethyl)-3,3-dimethylindolinone-6'-nitrobenzopyrilospiran, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,1'-biimidazole, and 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole (all manufactured by Tokyo Chemical Industry Co., Ltd.).

[0067] Other photochromic materials include "Reversacol Amazon Green," "Reversacol Amber," "Reversacol Atlantic Blue," "Reversacol Berry Red," "Reversacol Citrus Yellow," "Reversacol Corn Yellow," "Reversacol Flame," "Reversacol Graphite," "Reversacol Heather," "Reversacol Leaf Green," "Reversacol Leather Brown," "Reversacol Midnight Grey," and "Reversacol Misty." Grey”, “Reversacol Mulberry”, “Reversacol Ocean Blue”, “Reversacol Olivine”, “Reversacol Oxford Blue”, “Reversacol "Palatinate Purple", "Reversacol Plum Red", "Reversacol Rio Blue", "Reversacol Ruby Red", "Reversacol Rush" "Yellow", "Reversacol Solar Yellow", "Reversacol Storm Purple", "Reversacol Sunflower", "Reversacol Velvet" Among the above, the Reversacol series manufactured by James Robinson Specialty Ingredients is preferred because the laminate structure of the present disclosure easily achieves both weather resistance and photochromic performance.

[0068] Photochromic materials are transformed from a first isomer to a second isomer upon irradiation with light of a specific wavelength range (e.g., ultraviolet light). The isomerization reaction of photochromic materials is reversible, and they can revert from the second isomer to the first isomer under specific conditions, for example, upon irradiation with light of a specific wavelength range and / or heat. The isomerization reaction from the first isomer to the second isomer is also called a "forward isomerization reaction." The isomerization reaction from the second isomer to the first isomer is also called a "reverse isomerization reaction."

[0069] Photochromic materials are classified into two types: P-type, in which the reverse isomerization reaction occurs only upon irradiation with light in a specific wavelength range, and "T-type," in which the reverse isomerization reaction occurs upon irradiation with light in a specific wavelength range and / or heat. The photochromic layer preferably contains one or more T-type photochromic materials. T-type photochromic materials can undergo a reverse isomerization reaction upon heat at room temperature (20-30°C), and are preferred because they do not require special operations or equipment for the reverse isomerization reaction. T-type photochromic materials change from a transparent state to a colored state upon irradiation with light in a specific wavelength range, such as sunlight including ultraviolet light, and can return from the colored state to a transparent state upon cessation of irradiation with light in the specific wavelength range without any special treatment upon heat at room temperature (20-30°C). Examples of T-type photochromic materials include triarylmethane compounds, stilbene compounds, azastilbene compounds, nitrone compounds, azobenzene compounds, quinone compounds, spirooxazine compounds, spironaphthoxazine compounds, hexaarylbiimidazole compounds, naphthopyran compounds, spiropyran compounds, and inorganic photochromic materials. Among these, naphthopyran compounds are preferred from the viewpoints of availability, durability, and color development.

[0070] The film laminate of the present disclosure preferably satisfies the following formula (I) when the visible light transmittance (Tlv) (measured value) of the film laminate before UV irradiation and the visible light transmittance (Tdv) (measured value) of the film laminate after UV irradiation are determined by the following method: 1.5≦Tlv (measured value) / Tdv (measured value)≦20 (I) [Measurement Method] The transmission spectrum of the film laminate before UV irradiation is measured using a spectrophotometer under conditions of a measurement temperature of 23°C, a measurement wavelength range of 380 to 780 nm, and a scan speed of 1200 nm / min. From the obtained transmission spectrum, the visible light transmittance (Tlv) (measured value) is determined in accordance with JIS R3212:2015 and JIS Z8722:2009. Next, the photochromic layer included in the film laminate is irradiated with simulated sunlight containing UV light from the UV-shielding layer side at an intensity of 1 sun for 60 seconds. 20 seconds after the end of the ultraviolet irradiation, the transmission spectrum of the film laminate after ultraviolet irradiation is measured in the same manner as before ultraviolet irradiation to determine the visible light transmittance (Tdv) (measured value).

[0071] In the film laminate of the present disclosure, if Tlv (measured value) / Tdv (measured value) is equal to or greater than the above lower limit, the difference in appearance before and after ultraviolet irradiation is easily visible to the naked eye, and the photochromic function can be effectively exhibited. If Tlv (measured value) / Tdv (measured value) is equal to or less than the above upper limit, the amount of photochromic material required can be reduced, thereby reducing material costs. The lower limit of Tlv (measured value) / Tdv (measured value) is more preferably 2.0, particularly preferably 2.5, and most preferably 3.0. The upper limit of Tlv / Tdv is more preferably 17, even more preferably 15, particularly preferably 10, and most preferably 7.

[0072] The content of the photochromic material in the photochromic layer (the total amount if multiple types are used, unless otherwise specified) is not particularly limited and can be determined so that Tlv (actual measured value) / Tdv (actual measured value) falls within a preferred range depending on the type of photochromic material and the thickness of the photochromic layer. The content of the photochromic material in the photochromic layer is preferably 0.01 to 5 parts by mass per 100 parts by mass of the total of the thermoplastic resin containing polyvinyl acetal and the plasticizer. The lower limit is more preferably 0.05 parts by mass, particularly preferably 0.1 parts by mass, and most preferably 0.15 parts by mass. The upper limit is more preferably 4 parts by mass, even more preferably 3 parts by mass, even more preferably 2 parts by mass, particularly preferably 1 part by mass, and most preferably 0.5 parts by mass.

[0073] (Light Stabilizer) The photochromic layer may contain one or more light stabilizers as needed. The light stabilizer can capture and detoxify radicals (specifically, alkyl radicals, peroxide radicals, etc.) generated by heat and / or ultraviolet light. One or more known light stabilizers may be used as the light stabilizer.

[0074] The light stabilizer preferably contains one or more renewable hindered amine light stabilizers (HALS). Examples of hindered amine light stabilizers (HALS) include NH-type HALS having an imino group (>N-H), NR-type HALS having an imino group (>N-H) with an organic group (>N-R) in which the H of the imino group (>N-H) is substituted with an alkyl group (e.g., a methyl group), and NOR-type HALS having an imino group (>N-H) with an organic group (>N-OR) in which the H of the imino group (>N-H) is substituted with an organic group (>N-OR). Here, R represents a substituted or unsubstituted saturated or unsaturated hydrocarbon group. Examples of R include alkyl groups, aralkyl groups, and aryl groups. The alkyl group may be linear, branched, or cyclic. Hindered amine light stabilizers other than NOR-type HALS, such as NH-type and NR-type HALS, are collectively referred to as "non-NOR-type hindered amine light stabilizers."

[0075] As the light stabilizer, a NOR-type hindered amine light stabilizer (NOR-type HALS) is preferred. In this case, one or more non-NOR-type hindered amine light stabilizers (non-NOR-type HALS) may be used in combination. N-OR groups such as N-alkoxy groups can effectively capture radicals. N-OR groups such as N-alkoxy groups can effectively capture radicals generated from the photochromic material even in an environment where oxygen is not supplied. As the NOR-type HALS, a NOR-type HALS having an alkoxyimino group is preferred. Examples include NOR-type HALS disclosed in JP-A 2002-507238, WO 2005 / 082852, WO 2008 / 003605, etc.

[0076] Specific examples of NOR type HALS include 1-cyclohexyloxy-2,2,6,6-tetramethyl-4-octadecylaminopiperidine; bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate; 2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-(2-hydroxyethylamino)-s-triazine; bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)adipate; 4,4'-hexa an oligomeric compound which is the condensation product of methylenebis(amino-2,2,6,6-tetramethylpiperidine) and 2,4-dichloro-6-[(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6-bis(dibutylamino)-s-triazine; oligomeric compounds which are condensation products of 2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)-butylamino]-s-triazine with 2,4-bis[(1-cyclohexyloxy-2,2,6,6-piperidin-4-yl)-6-chloro-s-triazine]; and reaction products of peroxidized 4-butylamino-2,2,6,6-tetramethylpiperidine, 2,4,6-trichloro-s-triazine, cyclohexane, and N,N'-ethane-1,2-diylbis(1,3-propanediamine). (N,N',N'''-tris{2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)n-butylamino]-s-triazin-6-yl}-3,3'-ethylenediiminodipropylamine); bis(1-undecanoxy-2,2,6,6-tetramethylpiperidin-4-yl)carbonate; 1-undecyloxy-2,2,6,6-tetramethylpiperidin-4-one; bis(1-stearyloxy-2,2,6,6-tetramethylpiperidin-4-yl)carbonate, and the like.

[0077] Commercially available NOR-type HALS or non-NOR-type HALS include BASF's "Chimassorb 2020 FDL", "Chimassorb 944 FDL", "Tinuvin 622 SF", "Tinuvin PA 144", "Tinuvin 765", "Tinuvin 770 DF", "Tinuvin XT 55 FB", "Tinuvin 111 FDL", "Tinuvin 783 FDL", "Tinuvin XT 850 FF", "Tinuvin XT 855 FF”, “Flamestab NOR 116 FF”, “Tinuvin 123”, “Tinuvin 152”, “Tinuvin 292”, “Tinuvin 5100", "Tinuvin 249", "Tinuvin 5050", "Tinuvin 5151" manufactured by ADEKA Corporation; "ADK STAB LA-52", "ADK STAB LA-57", "ADK STAB LA-63P", "ADK STAB LA-68", "ADK STAB LA-72", "ADK STAB LA-77Y / ADK STAB LA-77G", "ADK STAB LA-81", "ADK STAB LA-82", "ADK STAB LA-87", "ADK STAB LA-402F", "ADK STAB LA-40MP / ADK STAB LA-40Si" and the like.

[0078] Among these, NOR-type HALS such as "Tinuvin XT 850 FF," "Flamestab NOR 116 FF," "Tinuvin 123," and "Tinuvin 152" manufactured by BASF, and "ADK STAB LA-81" manufactured by ADEKA are preferred. In particular, "Tinuvin 123," "Tinuvin 152," and "ADK STAB LA-81" are preferred because of their high fluidity and excellent radical scavenging ability.

[0079] The content of the light stabilizer in the photochromic layer (the total amount when multiple types are used, unless otherwise specified) is not particularly limited, and is preferably 0.01 to 5 parts by mass relative to 100 parts by mass of the total of the thermoplastic resin containing polyvinyl acetal and the plasticizer. The lower limit is more preferably 0.05 parts by mass, particularly preferably 0.1 parts by mass, and most preferably 0.15 parts by mass. The upper limit is more preferably 4 parts by mass, even more preferably 3 parts by mass, particularly preferably 2 parts by mass, and most preferably 1 part by mass. When the content of the light stabilizer is equal to or greater than the lower limit, the radical scavenging function of the light stabilizer can be favorably obtained, while when the content is equal to or less than the upper limit, discoloration of the photochromic layer and / or bleeding out of the light stabilizer due to the addition of the light stabilizer can be suppressed.

[0080] (Infrared Shielding Agent) The infrared shielding agent that can be contained in the ultraviolet shielding layer, photochromic layer, separator layer, infrared shielding layer, or other functional layer may be either an infrared absorbing type or an infrared reflecting type, with an infrared reflecting type being preferred. Examples of infrared reflective films suitable as the infrared shielding layer include the nano-laminate film "PICASUS (registered trademark) IR" manufactured by Toray Industries, Inc., "Ultra-Clear Solar Film (USCF)" manufactured by 3M, and the metal film coated film "XIR (registered trademark)" manufactured by Eastman.

[0081] (Thermoplastic Resin) The ultraviolet shielding layer contains one or more thermoplastic resins. Examples of the thermoplastic resin include thermoplastic resins used as materials for laminated glass interlayers, specifically polyvinyl acetal, ionomer, ethylene-vinyl acetate copolymer, cycloolefin polymer, polyester, polyurethane, and combinations thereof, with polyvinyl acetal being preferred. The photochromic layer contains one or more polyvinyl acetals and, if necessary, can further contain one or more other thermoplastic resins. Examples of the other thermoplastic resins include ionomer, ethylene-vinyl acetate copolymer, cycloolefin polymer, polyester, polyurethane, and combinations thereof.

[0082] The content of the thermoplastic resin in the ultraviolet-shielding layer (the total amount when multiple types are used, unless otherwise specified) is not particularly limited and is preferably 60 to 99.9% by mass. The lower limit is more preferably 65% ​​by mass, and particularly preferably 70% by mass. The upper limit is more preferably 99.5% by mass, even more preferably 99% by mass, even more preferably 98% by mass, even more preferably 95% by mass, even more preferably 90% by mass, even more preferably 85% by mass, particularly preferably 80% by mass, and most preferably 75% by mass. When the content of the thermoplastic resin in the ultraviolet-shielding layer is within the above range, the ultraviolet-shielding layer is easily formed, the contents of the ultraviolet absorber and the plasticizer, if included as needed, in the ultraviolet-shielding layer can be suitably designed, the desired ultraviolet-shielding function can be obtained, and bleed-out of the plasticizer can be suppressed.

[0083] The content of polyvinyl acetal in the photochromic layer (total amount when multiple types are used unless otherwise specified) is not particularly limited and is preferably 60 to 99.9% by mass. The lower limit is more preferably 65% ​​by mass, and particularly preferably 70% by mass. The upper limit is more preferably 99.5% by mass, even more preferably 99% by mass, even more preferably 98% by mass, even more preferably 95% by mass, even more preferably 90% by mass, even more preferably 85% by mass, particularly preferably 80% by mass, and most preferably 75% by mass. When the content of polyvinyl acetal in the photochromic layer is within the above range, the photochromic layer is easily formed, the contents of the photochromic material and plasticizer in the photochromic layer can be suitably designed, the desired photochromic function can be obtained, and bleed-out of the plasticizer can be suppressed.

[0084] <Polyvinyl Acetal> The polyvinyl acetal that can be contained in the photochromic layer and the ultraviolet-shielding layer is a resin produced by acetalization of a polyvinyl alcohol-based resin such as polyvinyl alcohol or an ethylene-vinyl alcohol copolymer. The ultraviolet-shielding layer and / or the photochromic layer may contain two or more types of polyvinyl acetal that differ in one or more properties selected from the group consisting of viscosity-average degree of polymerization, degree of acetalization, vinyl acetate unit content, vinyl alcohol unit content, ethylene unit content, molecular weight of aldehyde used in acetalization, and chain length.

[0085] Polyvinyl acetal can be produced by known methods, for example, by the following method. First, an aqueous solution of polyvinyl alcohol and / or ethylene-vinyl alcohol copolymer with a concentration of 3 to 30% by mass is maintained at a temperature range of 80 to 100°C and then gradually cooled over 10 to 60 minutes. When the temperature has dropped to -10 to 30°C, an aldehyde and / or ketone compound and an acid catalyst are added, and the acetalization reaction is carried out for 30 to 300 minutes while maintaining the temperature constant. Next, the reaction solution is heated to a temperature of 20 to 80°C over 30 to 200 minutes and maintained at that temperature for 30 to 300 minutes. Next, the reaction solution is filtered as needed, and then neutralized by adding a neutralizing agent such as an alkali. Next, the resulting resin is filtered, washed with water, and dried. In this manner, polyvinyl acetal is produced.

[0086] The acid catalyst used in the acetalization reaction is not particularly limited and may be either an organic acid or an inorganic acid. Examples of the acid catalyst include acetic acid, paratoluenesulfonic acid, nitric acid, sulfuric acid, and hydrochloric acid. Among them, hydrochloric acid, sulfuric acid, and nitric acid are preferred from the viewpoints of acid strength and ease of removal during washing.

[0087] From the viewpoint of easily obtaining a polyvinyl acetal having a suitable breaking energy, the aldehyde or ketone compound used in the production of the polyvinyl acetal preferably has a linear, branched, or cyclic molecular structure having 2 to 10 carbon atoms, more preferably a linear or branched molecular structure, which results in a corresponding linear or branched acetal group.

[0088] One or more aldehyde and / or ketone compounds can be used, and at least one of them is preferably one or more aliphatic unbranched aldehydes having 2 to 10 carbon atoms. As such an aldehyde, n-butyl aldehyde and the like are preferred from the viewpoint of facilitating the production of polyvinyl acetal having suitable breaking energy. The amount of n-butyl aldehyde in the one or more aldehyde and / or ketone compounds used for acetalization is preferably 50% by mass or more, more preferably 80% by mass or more, particularly preferably 95% by mass or more, and most preferably 99% by mass or more, and may even be 100% by mass.

[0089] Polyvinyl acetal may be produced by combining multiple types of polyvinyl alcohol and / or ethylene-vinyl alcohol copolymers having different properties, such as viscosity-average degree of polymerization or degree of hydrolysis. The viscosity-average degree of polymerization of the raw material polyvinyl alcohol is not particularly limited, but is preferably 100 to 5,000. The lower limit is more preferably 300, more preferably 400, even more preferably 600, particularly preferably 700, and most preferably 750. The upper limit is more preferably 3,000, even more preferably 2,500, particularly preferably 2,300, and most preferably 2,000. When the viscosity-average degree of polymerization of polyvinyl alcohol is equal to or greater than the lower limit, misalignment of the light-transmitting substrate at high temperatures is likely to be suppressed in the resulting laminate, such as laminated glass. When the viscosity-average degree of polymerization of polyvinyl alcohol is equal to or less than the upper limit, film formability of a film containing polyvinyl acetal is improved.

[0090] The viscosity-average degree of polymerization of polyvinyl alcohol can be measured, for example, in accordance with JIS K 6726:1994 "Testing Methods for Polyvinyl Alcohol." Since the viscosity-average degree of polymerization of polyvinyl acetal usually coincides with that of the starting polyvinyl alcohol, the preferred viscosity-average degree of polymerization of polyvinyl alcohol described above coincides with that of the resulting polyvinyl acetal. When the ultraviolet-shielding layer and / or photochromic layer contain two or more polyvinyl acetals, it is preferred that the viscosity-average degree of polymerization of at least one polyvinyl acetal be within the above-mentioned range.

[0091] The amount of acetyl groups in the polyvinyl acetal can be adjusted by appropriately adjusting the degree of saponification of the raw material polyvinyl alcohol and / or ethylene-vinyl alcohol copolymer. The polarity of the polyvinyl acetal changes depending on the amount of acetyl groups, and this allows adjustment of the compatibility with a plasticizer, which is added as needed, and the mechanical strength of the resulting polyvinyl acetal-containing film.

[0092] The amount of acetyl groups in the polyvinyl acetal is preferably 0 to 20 mol %, more preferably 0 to 3 mol %, based on the ethylene units in the polyvinyl acetal main chain. The amount of acetyl groups can be adjusted to within the above range by appropriately adjusting the degree of saponification of the raw material polyvinyl alcohol. When the ultraviolet-shielding layer and / or the photochromic layer contains a polyvinyl acetal having an acetyl group amount within the above range, good adhesion and reduced optical distortion are likely to be achieved. When the ultraviolet-shielding layer and / or the photochromic layer contains two or more types of polyvinyl acetal, it is preferable that the amount of acetyl groups in at least one of the polyvinyl acetals is within the above range.

[0093] The degree of acetalization of the polyvinyl acetal is not particularly limited, but is preferably 40 to 86 mol%, more preferably 45 to 84 mol%, even more preferably 50 to 82 mol%, particularly preferably 60 to 82 mol%, and most preferably 68 to 82 mol%. The degree of acetalization of the polyvinyl acetal can be adjusted within the above range by appropriately adjusting the amount of aldehyde and / or ketone compound used when acetalizing the polyvinyl alcohol resin. When the degree of acetalization is within the above range, the mechanical strength of the polyvinyl acetal and the compatibility with a plasticizer added as needed are improved. When the ultraviolet-shielding layer and / or photochromic layer contain two or more types of polyvinyl acetal, it is preferable that the degree of acetalization of at least one type of polyvinyl acetal is within the above range.

[0094] The hydroxyl group content of the polyvinyl acetal (the amount of hydroxyl groups remaining after acetal modification) is not particularly limited and is preferably 6 to 26% by mass, more preferably 12 to 24% by mass, particularly preferably 15 to 22% by mass, and most preferably 18 to 21% by mass, based on the ethylene units in the polyvinyl acetal main chain. When sound insulation performance is to be imparted to the ultraviolet-shielding layer and / or photochromic layer, the hydroxyl group content is preferably 6 to 20% by mass, more preferably 8 to 18% by mass, particularly preferably 10 to 15% by mass, and most preferably 11 to 13% by mass. The hydroxyl group content can be adjusted within the above range by adjusting the amount of aldehyde used during acetalization of the polyvinyl alcohol resin. A hydroxyl group content within the above range facilitates the production of laminated glass and other laminates with minimal optical unevenness. When the ultraviolet-shielding layer and / or photochromic layer contains two or more polyvinyl acetals, it is preferable that the hydroxyl group content of at least one of the polyvinyl acetals be within the above range.

[0095] Polyvinyl acetal is usually composed of acetal group-containing units, hydroxyl group-containing units, and acetyl group-containing units, and the amount of each unit can be measured, for example, according to JIS K 6728:1977 "Testing Methods for Polyvinyl Butyral" or by nuclear magnetic resonance (NMR). When polyvinyl acetal contains units other than those mentioned above, the amount of hydroxyl group-containing units and the amount of acetyl group-containing units are measured, and the amount of these units is subtracted from the amount of acetal group-containing units in the case where no other units are contained, thereby calculating the amount of remaining acetal group-containing units.

[0096] The viscosity-average degree of polymerization of the polyvinyl acetal is not particularly limited. Unless otherwise specified in this specification, the viscosity of the polyvinyl acetal is the viscosity measured using a Brookfield (B-type) viscometer at 20°C and 30 rpm on a solution prepared by adjusting the concentration of the polyvinyl acetal to 10% by mass using a mixed solvent of toluene and ethanol in a mass ratio of 1:1. The viscosity of the polyvinyl acetal contained in the ultraviolet-shielding layer and / or photochromic layer is preferably greater than 200 mPa·s, more preferably 210 mPa·s or greater, more preferably 220 mPa·s or greater, even more preferably 230 mPa·s or greater, particularly preferably 240 mPa·s or greater, and most preferably 265 mPa·s or greater. When the viscosity of the polyvinyl acetal is greater than 200 mPa·s, displacement of the translucent substrate of a laminate such as laminated glass at high temperatures is easily suppressed. By using a polyvinyl acetal produced using a polyvinyl alcohol having a relatively high viscosity average degree of polymerization as a raw material or as part of the raw material, the viscosity of the polyvinyl acetal can be adjusted to more than 200 mPa s. Note that when the ultraviolet-shielding layer and / or the photochromic layer contain two or more types of polyvinyl acetal, the viscosity mentioned above is the viscosity of a mixture of these. From the viewpoint of good film-forming properties, the viscosity mentioned above is usually 1000 mPa s or less, preferably 800 mPa s or less, more preferably 500 mPa s or less, particularly preferably 450 mPa s or less, and most preferably 400 mPa s.

[0097] The peak-top molecular weight of the polyvinyl acetal contained in the ultraviolet-shielding layer and / or the photochromic layer is not particularly limited, and is preferably 115,000 to 200,000, more preferably 120,000 to 160,000, and particularly preferably 130,000 to 150,000. By using a polyvinyl acetal produced using a polyvinyl alcohol with a high viscosity-average degree of polymerization as a raw material or as part of the raw material, the peak-top molecular weight of the polyvinyl acetal can be adjusted to fall within the above range. When the peak-top molecular weight of the polyvinyl acetal falls within the above range, favorable film-forming properties and favorable film properties (e.g., thermocompression bonding suitability, creep resistance, and elongation at break) are likely to be obtained.

[0098] The molecular weight distribution of the polyvinyl acetal contained in the ultraviolet-shielding layer and / or the photochromic layer, defined as the ratio (Mw / Mn) of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn), is not particularly limited and is preferably 2.7 to 10. The lower limit is more preferably 2.8, and particularly preferably 2.9. The upper limit is preferably 8, and more preferably 5. The molecular weight distribution of the polyvinyl acetal can be adjusted by acetalizing two or more polyvinyl alcohols having different viscosity-average degrees of polymerization, or by mixing two or more acetalized polyvinyl alcohols having different viscosity-average degrees of polymerization. When the molecular weight distribution of the polyvinyl acetal is equal to or greater than the lower limit, it is easy to achieve both favorable film-forming properties and favorable film properties (e.g., thermocompression bonding suitability, creep resistance, and breaking strength). When the molecular weight distribution of the polyvinyl acetal is equal to or less than the upper limit, it is easy to form the photochromic layer. When the ultraviolet-shielding layer and / or the photochromic layer contains two or more polyvinyl acetals, it is preferable that the peak-top molecular weight and molecular weight distribution of at least one of the polyvinyl acetals are within the above-mentioned ranges. The peak-top molecular weight and molecular weight distribution can be determined, for example, by gel permeation chromatography (GPC) using polystyrene of known molecular weight as a standard.

[0099] The ultraviolet-shielding layer and / or the photochromic layer preferably contain uncrosslinked polyvinyl acetal, from the viewpoint of easily obtaining good film-forming properties, or may contain crosslinked polyvinyl acetal. For crosslinking methods of polyvinyl acetal, see, for example, EP 1527107 and WO 2004 / 063231 (thermal self-crosslinking of carboxyl group-containing polyvinyl acetal), EP 1606325 (polyvinyl acetal crosslinked with polyaldehyde), and WO 2003 / 020776 (polyvinyl acetal crosslinked with glyoxylic acid). By appropriately adjusting the acetalization reaction conditions, the amount of intermolecular acetal bonds and the degree of blocking of residual hydroxyl groups can also be adjusted.

[0100] <Ionomer> The ionomer that can be contained in the ultraviolet-shielding layer and / or photochromic layer is a resin having structural units derived from ethylene and structural units derived from an α,β-unsaturated carboxylic acid, in which at least a portion of the α,β-unsaturated carboxylic acid is neutralized with a metal ion. Examples of the α,β-unsaturated carboxylic acid include (meth)acrylic acid, maleic acid, monomethyl maleate, monoethyl maleate, and maleic anhydride, with (meth)acrylic acid being preferred. Examples of the metal ion include sodium ions. In the ethylene-α,β-unsaturated carboxylic acid copolymer serving as the base polymer, the content of the α,β-unsaturated carboxylic acid structural units is preferably 2 to 30% by mass. The lower limit is more preferably 5% by mass, and the upper limit is more preferably 30% by mass, and particularly preferably 20% by mass. From the viewpoint of availability, ionomers of ethylene-(meth)acrylic acid copolymers are preferred. Suitable examples of ethylene-based ionomers include sodium ionomers of ethylene-(meth)acrylic acid copolymers.

[0101] (Plasticizer) The plasticizer that the photochromic layer and the ultraviolet-shielding layer may contain is not particularly limited, and one or more of the following examples (Pa) to (Pe) may be used. (Pa) Esters of polyvalent aliphatic or aromatic acids. Examples of such esters include dialkyl adipates (e.g., dihexyl adipate, di-2-ethylbutyl adipate, dioctyl adipate, di-2-ethylhexyl adipate, hexylcyclohexyl adipate, diheptyl adipate, dinonyl adipate, diisononyl adipate, and heptylnonyl adipate); esters of adipic acid and an alcohol containing an alicyclic structure or an ether structure (e.g., di(butoxyethyl) adipate); di(butoxyethoxyethyl)adipate; dialkyl sebacates (for example, dibutyl sebacate); esters of sebacic acid and alcohols containing an alicyclic structure or an ether structure; esters of phthalic acid (for example, butyl benzyl phthalate and bis-2-butoxyethyl phthalate); esters of alicyclic polycarboxylic acids and aliphatic alcohols (for example, 1,2-cyclohexanedicarboxylic acid diisononyl ester).

[0102] (P-b) Esters or ethers of polyhydric aliphatic or aromatic alcohols or oligoether glycols having one or more aliphatic or aromatic substituents. Examples of such esters or ethers include esters of glycerin, diglycol, triglycol, tetraglycol, or the like with linear or branched aliphatic or alicyclic carboxylic acids. Specific examples include diethylene glycol bis-(2-ethylhexanoate), triethylene glycol bis-(2-ethylhexanoate) (3GO), triethylene glycol bis-(2-ethylbutanoate), tetraethylene glycol bis-n-heptanoate, triethylene glycol bis-n-heptanoate, triethylene glycol bis-n-hexanoate, tetraethylene glycol dimethyl ether, and dipropylene glycol dibenzoate.

[0103] (P-c) Phosphate esters of aliphatic or aromatic alcohols. Examples of such phosphate esters include tris(2-ethylhexyl)phosphate (TOF), triethylphosphate, diphenyl-2-ethylhexylphosphate, and tricresylphosphate. (P-d) Esters of citric acid, succinic acid, or fumaric acid. (P-e) Polyesters or oligoesters obtained from polyhydric alcohols and polycarboxylic acids; terminal esterified or etherified products thereof; polyesters or oligoesters obtained from lactones or hydroxycarboxylic acids; terminal esterified or etherified products thereof.

[0104] The plasticizer is preferably one that does not impair the physical properties of the resin layer (ultraviolet shielding layer and / or photochromic layer) containing the plasticizer. Specifically, triethylene glycol-bis-(2-ethylhexanoate) (also referred to as 3G8 or 3GO), triethylene glycol-bis(2-ethylbutanoate), tetraethylene glycol-bis(2-ethylhexanoate), and tetraethylene glycol-bisheptanoate are preferred, with triethylene glycol-bis-(2-ethylhexanoate) (3G8) being particularly preferred.

[0105] The content of plasticizer in the ultraviolet-shielding layer (total amount if multiple types are used unless otherwise specified) is not particularly limited, and from the viewpoints of film-forming ability, penetration resistance, and suppression of plasticizer bleed-out, it is preferably 0 to 40 parts by mass per 100 parts by mass of the thermoplastic resin and plasticizer combined. The lower limit is more preferably 0.5 parts by mass, even more preferably 1 part by mass, even more preferably 5 parts by mass, even more preferably 10 parts by mass, even more preferably 15 parts by mass, particularly preferably 20 parts by mass, and most preferably 25 parts by mass. The upper limit is more preferably 35 parts by mass, particularly preferably 30 parts by mass.

[0106] The content of plasticizer in the photochromic layer (total amount if multiple types are used unless otherwise specified) is not particularly limited, and from the viewpoints of film-forming ability, penetration resistance, and suppression of plasticizer bleed-out, it is preferably 0.1 to 40 parts by mass per 100 parts by mass of the total of the thermoplastic resin containing polyvinyl acetal and the plasticizer. The lower limit is more preferably 0.5 parts by mass, even more preferably 1 part by mass, even more preferably 5 parts by mass, even more preferably 10 parts by mass, even more preferably 15 parts by mass, particularly preferably 20 parts by mass, and most preferably 25 parts by mass. The upper limit is more preferably 35 parts by mass, particularly preferably 30 parts by mass.

[0107] As described above, the suitable response speed (coloring speed and / or fading speed) of light-controlling glass varies depending on the application, etc. In a photochromic layer containing an appropriate amount of plasticizer, even if the type and content of the photochromic material are the same, the response speed (coloring speed and / or fading speed) of the photochromic material can be changed by adjusting the type and / or amount of plasticizer. In the film laminate of the present disclosure, the response speed (coloring speed and / or fading speed) of the photochromic material can be easily adjusted or designed depending on the application, etc.

[0108] The time it takes for the photochromic layer to return from a colored state to a transparent state (i.e., the fading rate) and the transmittance during the fading process can be designed depending on the application, etc. If the fading rate of the photochromic layer is within an appropriate range, the color change of the photochromic layer is easily noticeable, and the color change is not too rapid, thereby achieving good photochromic function. Let Tlw (%) be the transmittance at the maximum absorption wavelength (w) in the transparent state, t (seconds) be the elapsed time from the time of coloring, and Tw(t) (%) be the transmittance at the maximum absorption wavelength (w) t (seconds) after the time of coloring. Tw(30) is preferably Tlw x 0.05 to Tlw x 0.5. The lower limit is more preferably Tlw x 0.1, and particularly preferably Tlw x 0.15. The upper limit is more preferably Tlw x 0.45. Tw(60) is preferably Tlw x 0.1 to Tlw x 0.7. The lower limit is more preferably Tlw×0.15, particularly preferably Tlw×0.2, and most preferably Tlw×0.3. Tw(120) is preferably Tlw×0.25 to Tlw×0.9. The lower limit is more preferably Tlw×0.3, particularly preferably Tlw×0.4, and particularly preferably Tlw×0.5.

[0109] (Separator Layer Material) The separator layer may contain one or more materials selected from the group consisting of polyester, polyvinyl alcohol, polycarbonate, polyvinyl acetal, ionomer, methacrylic resin, polyolefin, polyimide, and inorganic material. Polyester is preferred in terms of processability, transparency, availability, etc. Examples of polyester include polyethylene terephthalate (PET) and polyethylene naphthalate, with polyethylene terephthalate (PET) being preferred. The separator layer may contain one or more optional components other than those mentioned above. The separator layer may be free of ultraviolet screening agents, photochromic materials, and light stabilizers.

[0110] (Other Additives) The ultraviolet shielding layer, photochromic layer, or separator layer may contain one or more additives other than those described above, as necessary. Examples of other additives include antioxidants; peroxide decomposers, singlet oxygen quenchers, triplet quenchers; adhesion modifiers; colorants such as dyes, pigments, dyes, and luminescent materials; (fluorescent) brighteners; processing aids; impact modifiers; flow improvers; crosslinking agents; refractive index modifiers; heat-shielding materials; organic or inorganic nanoparticles (e.g., nanoparticles having infrared absorption or reflection capabilities); calcined silica; and surfactants.

[0111] Examples of antioxidants include phenol-based, phosphorus-based, lactone-based, hydroxyl-based, alkyl radical scavengers, and fullerene-based antioxidants. Among these, phenol-based antioxidants, phosphorus-based antioxidants, alkyl radical scavengers, fullerene, and combinations thereof are preferred.

[0112] Examples of phenolic antioxidants include 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 3-(3,5-di-tert-butyl-4-hydroxyphenyl)stearyl propionate, 4,4'-butylidenebis(6-tert-butyl-m-cresol), 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, and pentaerythritol. tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], bis[3-[3-(tert-butyl)-4-hydroxy-5-methylphenyl]propanoic acid]2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diylbis(2-methylpropane-2,1-diyl), and 1,3,5-trimethyl-2,4,6-tris(3',5'-di-t-butyl-4'-hydroxybenzyl).

[0113] Examples of phosphorus-based antioxidants include 3,9-bis(octadecyloxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, 2,4,8,10-tetra-tert-butyl-6-[(2-ethylhexan-1-yl)oxy]-12H-dibenzo[d,g][1,3,2]dioxaphosphocin, tris(2,4-di-tert-butylphenyl)phosphite, trisnonylphenylphosphite, diphenylisodecylphosphite, and triphenylphosphite biphenyl-4,4′-diylbis[bis(2,4-di-tert-butylphenoxy)phosphine].

[0114] An example of an alkyl radical scavenger is "Sumilizer GS" manufactured by Sumitomo Chemical Co., Ltd. Examples of fullerenes include "nanom (registered trademark) mix ST," "nanom spectrum A100," and "nanom spectrum E400" manufactured by Frontier Carbon Corporation, with "nanom spectrum A100" being preferred as it is less likely to yellow.

[0115] The adhesive strength adjuster may include magnesium acetate tetrahydrate.

[0116] (Total Thickness, Thickness of Each Layer) The total thickness and thickness of each layer of the film laminate of the present disclosure are not particularly limited and can be designed appropriately. ＦＬ ) is not particularly limited, and is preferably 100 to 1600 μm. The lower limit is more preferably 350 μm, even more preferably 500 μm, particularly preferably 600 μm, and most preferably 700 μm. The upper limit is more preferably 1200 μm, particularly preferably 1000 μm. When the total thickness of the film laminate is within the above range, excellent penetration resistance is likely to be obtained.

[0117] The thickness (T ＵＶＳ) is not particularly limited, and is preferably 50 to 800 μm from the viewpoint of exhibiting an ultraviolet shielding function. The lower limit is more preferably 100 μm, even more preferably 150 μm, even more preferably 200 μm, particularly preferably 250 μm, and most preferably 300 μm. The upper limit is more preferably 700 μm, particularly preferably 600 μm, and most preferably 500 μm.

[0118] The thickness (T ＰＣ ) is not particularly limited, and is preferably 50 to 800 μm from the viewpoint of photochromic function expression. The lower limit is more preferably 100 μm, even more preferably 150 μm, even more preferably 200 μm, particularly preferably 250 μm, and most preferably 300 μm. The upper limit is more preferably 700 μm, particularly preferably 600 μm, and most preferably 500 μm.

[0119] The thickness (T ＳＰ ) is not particularly limited, and is preferably 10 to 500 μm from the viewpoint of exhibiting the function as a separator and ensuring the thickness of the ultraviolet-shielding layer and the photochromic layer. The lower limit is more preferably 20 μm, even more preferably 30 μm, still more preferably 40 μm, particularly preferably 50 μm, and most preferably 80 μm. The upper limit is more preferably 400 μm, particularly preferably 300 μm, and most preferably 200 μm.

[0120] The thickness (T ＣＬ) is not particularly limited, and is preferably 10 to 1000 μm from the viewpoint of ensuring the function of the colored layer and the thickness of the photochromic layer. The lower limit is more preferably 20 μm, even more preferably 30 μm, even more preferably 40 μm, particularly preferably 50 μm, especially preferably 60 μm, and most preferably 80 μm. The upper limit is more preferably 800 μm, even more preferably 600 μm, even more preferably 500 μm, even more preferably 400 μm, especially preferably 300 μm, and most preferably 200 μm.

[0121] (Translucent Substrate) From the viewpoints of transparency, weather resistance, and mechanical strength, the translucent substrate included in the laminate of the present disclosure is preferably a glass plate or a glass laminate in which any one or more layers or elements are formed on at least one surface of a glass plate. Examples of the glass plate include inorganic glass (also simply referred to as "glass") and organic glass. The shape of the translucent substrate is not particularly limited, and it may be a flat plate without a curved surface or a plate with a curved surface. Examples of inorganic glass include float glass, tempered glass, semi-tempered glass, chemically strengthened glass, green glass, and quartz glass. Examples of organic glass include methacrylic resin sheets, polycarbonate resin sheets, polystyrene resin sheets, polyester resin sheets, polyimide resin sheets, and polycycloolefin resin sheets. Among these, inorganic glass, methacrylic resin sheets, or polycarbonate resin sheets are preferred, and inorganic glass is particularly preferred.

[0122] As described above, the present disclosure can provide a film laminate, a laminate film, and a laminate that include a photochromic layer with a favorable response speed and can more effectively improve weather resistance.

[0123] [Applications] The laminate of the present disclosure is suitable for applications such as window glass for moving bodies such as trains, electric trains, and automobiles, ships, and aircraft; and window glass for buildings. The laminate of the present disclosure is suitable for vehicle window glass such as windshields, rear windows, roof windows, and side windows. The laminate film of the present disclosure is suitable as an interlayer film for window glass for moving bodies such as vehicles or buildings. The film laminate of the present disclosure is suitable as a material for the above interlayer film.

[0124] Examples and comparative examples according to the present invention will be described. [Evaluation Items and Evaluation Methods] The evaluation items and evaluation methods are as follows. (Absorbance of UV-Shielding Film) The absorption spectrum of the UV-shielding film alone or the glass plate (G1) alone was measured using a spectrophotometer (Hitachi High-Tech Corporation's "UH4150") under conditions of a measurement temperature of 23°C, a measurement wavelength range of 300 to 800 nm, and a scan speed of 1200 nm / min. For the UV-shielding film alone, the absorbance at wavelengths of 360 nm, 380 nm, and 400 nm was determined from the obtained absorption spectrum. Representative absorption spectra of the UV-shielding film alone and the glass plate (G1) alone obtained in each of Examples E1 to E3 are shown in Figure 5.

[0125] (Optical Properties Before Weathering Test (Initial)) The optical properties of the laminated glass (glass laminate) obtained in each example before the weathering test (initial) were evaluated. First, the transmission spectrum of the laminated glass (glass laminate) in a colorless and transparent state (also referred to as the "light state") before ultraviolet irradiation was measured using a spectrophotometer ("UH4150" manufactured by Hitachi High-Tech Corporation) under conditions of a measurement temperature of 23°C, a measurement wavelength range of 300 to 800 nm, and a scan speed of 1200 nm / min. From the data of the wavelength range of 380 to 780 nm of the obtained transmission spectrum, the visible light transmittance (Tlv) (measured value) was calculated in accordance with JIS R3212:2015 and JIS Z8722:2009. In addition, the transmittance (Tlv) at the maximum absorption wavelength (specifically, 580 nm) was measured. ５８０ ) (actual measured value) was calculated.

[0126] Next, using a light guide irradiation type AM1.5G simulated sunlight source ("Solar Simulator HAL-320" manufactured by Asahi Spectroscopy Co., Ltd.), the laminated glass (glass laminate) was irradiated with simulated sunlight containing ultraviolet (UV) rays at an intensity of 1 sun for 60 seconds to color the photochromic layer. When the laminated glass (glass laminate) had a laminated structure of an ultraviolet-shielding layer and a photochromic layer, the simulated sunlight was irradiated from the ultraviolet-shielding layer side.

[0127] Twenty seconds after the end of the ultraviolet irradiation, the transmission spectrum of the laminated glass (glass laminate) in the colored state (also referred to as the dark state) after ultraviolet irradiation was measured in the same manner as before ultraviolet irradiation, and the visible light transmittance (Tdv) (measured value) was determined. In addition, the transmittance (Td ５８０ ) (actual measured value) was calculated.

[0128] Note that the T-type photochromic material's color returns to its original state when ultraviolet (UV) irradiation is stopped. Measurement of the transmission spectrum begins 20 seconds after the end of UV irradiation. Furthermore, during transmission spectrum measurement, scanning is performed from 800 nm to 300 nm at 1200 nm / min, taking 25 seconds from start to finish. Therefore, the transmittance at 800 nm at the start of UV irradiation is the transmittance 20 seconds before the transmittance (actual measured value) calculated from the transmission spectrum, and the transmittance at 300 nm at the end of UV irradiation is the transmittance 45 seconds (20 seconds + 25 seconds) before the transmittance (actual measured value) calculated from the transmission spectrum.

[0129] Therefore, the fading rate at each wavelength (for example, the maximum absorption wavelength (580 nm)) was measured, and based on the obtained data, the transmittance at each wavelength at the end of UV irradiation was calculated as the true transmittance at each wavelength in the colored state (dark state) after UV irradiation. In this way, the true visible light transmittance (Tdv (cal)) (theoretical value) at the end of UV irradiation was determined.

[0130] In the section [Examples], the visible light transmittance (Tlv) (measured value), visible light transmittance (Tdv) (measured value), and visible light transmittance (Tdv(cal)) (theoretical value) are data for laminated glass (glass laminate). As shown in Figure 5, the transmittance of the glass plate alone at each wavelength in the range of 400 to 800 nm was 85% or more or 90% or more, and the transmittance at 580 nm was 90.5%. Therefore, the data for the visible light transmittance (Tlv) (measured value), visible light transmittance (Tdv) (measured value), and visible light transmittance (Tdv(cal)) (theoretical value) of a film laminate or interlayer that does not include a pair of glass plates are the same as those for laminated glass (glass laminate).

[0131] (Optical Properties After Weathering Test) The laminated glass (glass laminate) obtained in each example was subjected to a weathering test of 200 cycles for a total of 600 hours in accordance with SAE J2527. When the laminated glass (glass laminate) included a laminated structure of an ultraviolet-shielding layer and a photochromic layer, light was irradiated from the ultraviolet-shielding layer side. Next, the transmission spectrum of the laminated glass (glass laminate) in a colorless and transparent state (Light state) after ultraviolet irradiation was measured in the same manner as before the weathering test, and the transmittance (Tl) at the maximum absorption wavelength (specifically, 580 nm) was measured. ５８０ ) (measured value) was determined. Next, the laminated glass (glass laminate) was irradiated with ultraviolet (UV) rays in the same manner as before the weather resistance test to color the photochromic layer. Next, the transmission spectrum of the laminated glass (glass laminate) in the colored state (dark state) after UV irradiation was measured in the same manner as before the weather resistance test, and the transmittance (Td ５８０ ) (measured value) was obtained. The performance retention rate of the photochromic material (also called PC performance retention rate) was calculated by dividing the Td ５８０ / Tl ５８０ Td after weather resistance test ５８０ / Tl ５８０ Ratio of ([Td after weather resistance test ５８０ / Tl ５８０ ] / [Td before weather resistance test ５８０ / Tl ５８０Since the PC performance retention rate was evaluated as the ratio of the value after the weather resistance test to the value before the weather resistance test, the data used for the calculation was the transmittance (actual measured value) rather than the true transmittance (theoretical value).

[0132] (Fade Reaction at 25°C) The fade change at the maximum absorption wavelength (580 m) of the laminated glasses (glass laminates) obtained in Examples (E1) to (E12) and Comparative Example (EC2) was measured at 25°C. The laminated glasses (glass laminates) were colored using the same method as described in (Optical Properties before Weathering Test (Initial)). However, for Example (E12), the transmittance did not decrease to the same level as in Example (E1) after 60 seconds of UV irradiation, so the UV irradiation time was set to 180 seconds. The time elapsed from the time of coloring was defined as t (seconds), and the transmittance at the maximum absorption wavelength (580 m) after t (seconds) (t is 0 to 600) from the time of coloring was measured as T ５８０ (t) (%) was measured, and T ５８０ (30), T ５８０ (60), T ５８０ The transmittance at the maximum absorption wavelength (580 nm) in the transparent state was calculated as Tl ５８０ (%) and evaluated according to the following criteria. Note that, for Comparative Example EC1, the transparent state did not return to normal in a room temperature environment (20 to 30°C) even after several days had passed since the coloring, so the color fading change was not measured and it was judged as poor (×). <Condition 1> T ５８０ (30) is Tl ５８０ ×0.1~Tl ５８０ × 0.5. <Condition 2> T ５８０ (60) is Tl ５８０ ×0.15~Tl ５８０ × 0.7. <Condition 3> T ５８０ (120) is Tl ５８０ ×0.5~Tl ５８０ ×0.9. Good (◯): T ５８０ (t) satisfied all conditions 1 to 3. ５８０ (t) satisfied conditions 1 and 2, but did not satisfy condition 3. Poor (x): T ５８０ (t) did not satisfy two or more of conditions 1 to 3.

[0133] [Materials] The materials used are as follows: <Polyvinyl acetal resin> (PVB1) "Mowital B75H" manufactured by Kuraray Co., Ltd., hydroxyl group content 26.2 to 30.2 mol% (18.0 to 21.0 mass%), acetyl group content 0 to 2.9 mol% (0 to 4.0 mass%), weight average molecular weight (Mw) 96,000 to 106,000.

[0134] <Plasticizer> (3G8) Triethylene glycol-bis-(2-ethylhexanoate).

[0135] <UV Screening Agents> (UVA1) Triazine-based UV absorber (manufactured by BASF, "Tinuvin (registered trademark) 479"), (UVA2) Benzotriazole-based UV absorber (manufactured by BASF, "Tinuvin (registered trademark) 326").

[0136] <Photochromic (PC) Materials> (PC1) "Reversacol Amazon Green" (naphthopyran-based compound) manufactured by James Robinson Specialty Ingredients, Inc. (PC2) "Reversacol Ocean Blue" (naphthopyran-based compound) manufactured by James Robinson Specialty Ingredients, Inc.

[0137] <Antioxidants> (AO1) Hindered phenol-based antioxidant (manufactured by BASF Corporation, "Irganox 245"), (AO2) Hindered phenol-based antioxidant (manufactured by BASF Corporation, "Irganox 3114"), (AO3) Fullerene (manufactured by Frontier Carbon Corporation, "nanom spectrum A100"), (AO4) Alkyl radical scavenger (manufactured by Sumitomo Chemical Co., Ltd., "Sumilizer GS").

[0138] <Light stabilizer> (HALS1) NOR type hindered amine light stabilizer (manufactured by BASF, "Tinuvin (registered trademark) 123"), (HALS2) NOR type hindered amine light stabilizer (manufactured by ADEKA, "ADEKA STAB LA-81").

[0139] <Adhesion modifier> (ADH1) Magnesium acetate tetrahydrate ((CH ３ COO) ２ Mg 4H２ O).

[0140] <Separator Layer Material> (PET1) 100 μm thick polyethylene terephthalate film.

[0141] Example (E1) (Preparation of UV-Shielding Film (UV-Absorbing Film, UVA Film)) 72.5 parts by mass of polyvinyl butyral (PVB1) and 27.5 parts by mass of triethylene glycol bis(2-ethylhexanoate) (3G8) as a plasticizer were mixed with 0.2 parts by mass of a triazine-based UV absorber (UVA1), 0.073 parts by mass of a hindered phenol-based antioxidant (AO1), and 0.03 parts by mass of magnesium acetate tetrahydrate (ADH1) as an adhesion modifier. These materials were kneaded using a plastomill to obtain a resin composition. The obtained resin composition was press-molded to obtain a 5 cm x 5 cm, 400 μm-thick UV-shielding film (UV-absorbing film, UVA film) having a single-layer structure consisting only of a UV-shielding layer (UV-absorbing layer, UVA layer).

[0142] (Preparation of Photochromic Film (PC Film)) 72.5 parts by mass of polyvinyl butyral (PVB1) and 27.5 parts by mass of triethylene glycol bis(2-ethylhexanoate) (3G8) as a plasticizer were mixed with 0.15 parts by mass of photochromic material (PC1), 0.15 parts by mass of photochromic material (PC1), 0.2 parts by mass of NOR-type hindered amine light stabilizer (HALS1), 0.073 parts by mass of hindered phenol-based antioxidant (AO1), and 0.03 parts by mass of magnesium acetate tetrahydrate (ADH1) as an adhesion modifier. These materials were kneaded using a plastomill to obtain a resin composition. The obtained resin composition was press-molded to obtain a photochromic film (PC film) having a single layer structure consisting only of a 5 cm x 5 cm, 400 μm thick photochromic layer (PC layer).

[0143] (Preparation of Film Laminate) A polyethylene terephthalate film (PET1) as a separator film and a photochromic film (PC film) were sequentially stacked on the obtained ultraviolet shielding film (ultraviolet absorbing film, UVA film) to obtain a film laminate (FL).

[0144] (Preparation of Laminated Glass (Glass Laminate)) A laminated glass (glass laminate) was prepared using the obtained film laminate (FL) as the material for the interlayer. The film laminate (FL) was sandwiched between a pair of glass plates (G1) (2 mm thick float glass), and the obtained temporary laminate was placed in a vacuum bag. The interior of the vacuum bag was reduced in pressure to -100 kPa (gauge pressure) at room temperature for 15 minutes using a vacuum pump, and then the temperature was raised to 100 ° C. while maintaining the reduced pressure, and heated for 60 minutes (pre-pressure bonding). After cooling to room temperature, the pressure was returned to normal, and the pre-pressure bonded body was removed. Next, the pre-pressure bonded body was placed in an autoclave and pressurized and heated at 140 ° C. and 1.2 MPa for 30 minutes (main pressure bonding). In this way, a laminated glass (glass laminate) (LB) was obtained, which included an interlayer having a laminated structure of an ultraviolet-shielding layer (ultraviolet-absorbing layer, UVA layer) / separator layer (PET layer) / photochromic layer (PC layer). The composition and thickness of each layer of the interlayer are shown in Table 1. In the table, "pts." means parts by mass.

[0145] [Examples (E2), (E3), (E5) to (E10), (E12), Comparative Example (EC1)] A film laminate (FL) and a laminated glass (glass laminate) (LB) were obtained in the same manner as in Example (E1), except that the composition of each layer was changed. The composition and thickness of each layer of the interlayer are shown in Tables 1 and 2.

[0146] [Example (E4)] A film laminate (FL) and a laminated glass (glass laminate) (LB) were obtained in the same manner as in Example (E1), except that a photochromic film (PC film) was superimposed directly on an ultraviolet-shielding film (ultraviolet-absorbing film, UVA film) to obtain a film laminate (FL). The composition and thickness of each layer of the interlayer are shown in Table 1.

[0147] Example (E11) A colored film (CF1) containing polyvinyl acetal and a gray colorant ("Trosifol V705ARx Dusk Gray" manufactured by Kuraray Co., Ltd., 760 μm thick) was prepared. A film laminate (FL) and a laminated glass (glass laminate) (LB) were obtained in the same manner as in Example (E10), except that a polyethylene terephthalate film (PET1) as a separator film, a photochromic film (PC film), and the colored film (CF1) were sequentially stacked on an ultraviolet-shielding film (ultraviolet-absorbing film, UVA film) to obtain a film laminate (FL). The composition and thickness of each layer of the interlayer are shown in Table 2.

[0148] Comparative Example (EC2) (Preparation of Photochromic Film (PC Film)) To 72.5 parts by mass of polyvinyl butyral (PVB1) and 27.5 parts by mass of triethylene glycol bis(2-ethylhexanoate) (3G8) as a plasticizer, 0.1 parts by mass of triazine-based ultraviolet absorber (UVA1), 0.073 parts by mass of hindered phenol-based antioxidant (AO1), 0.03 parts by mass of magnesium acetate tetrahydrate (ADH1) as an adhesion modifier, 0.075 parts by mass of photochromic material (PC1), 0.075 parts by mass of photochromic material (PC2), and 0.1 parts by mass of hindered amine-based light stabilizer (HALS1) were added. These materials were kneaded using a Plastomill to obtain a resin composition. The resulting resin composition was press-molded to obtain a single-layer photochromic film (PC film) measuring 5 cm x 5 cm and 800 μm in thickness, consisting solely of a photochromic layer (PC layer). Laminated glass (glass laminate) (LB) was obtained in the same manner as in Example (E1), except that the resulting photochromic film (PC film) was used as the interlayer material. The composition and thickness of the interlayer are shown in Table 2.

[0149]

[0150]

[0151] [Summary of Results] The laminated glasses (glass laminates) obtained in Examples (E1) to (E12) had a laminated structure including an interlayer film, an ultraviolet-shielding layer, and a photochromic layer, the photochromic layer including polyvinyl acetal, a plasticizer, and a photochromic material, the ultraviolet-shielding layer transmitted at least a portion of light in a specific wavelength range that isomerizes the photochromic material, and had an absorbance of 1.0 or more at a wavelength of 360 nm.

[0152] The laminated glass (glass laminate) obtained in Comparative Example (EC1) had an interlayer film with a laminated structure including an ultraviolet-shielding layer and a photochromic layer, but no plasticizer was added to the photochromic layer. The laminated glass (glass laminate) obtained in Comparative Example (EC2) had an interlayer film with a single-layer structure consisting of only a photochromic layer containing an ultraviolet-shielding agent and a photochromic material.

[0153] The laminated glass (glass laminate) obtained in these Examples and Comparative Examples showed a change in transmission spectrum upon UV irradiation, changing from a transparent state to a colored state. In Examples (E1) to (E12) and Comparative Example (EC2), the photochromic layer contained a T-type photochromic material and an appropriate amount of plasticizer. Therefore, when UV irradiation was stopped, the colored state naturally returned to a transparent state due to the heat of a room temperature environment (20 to 30°C) without any special treatment. Representative measurement results of the color fading change in Examples (E1) and (E12) are shown in Figure 7. The laminated glass (glass laminate) obtained in Examples (E1) to (E11) exhibited a fast and excellent photochromic layer fading rate. The laminated glass (glass laminate) obtained in Example (E12), in which the amount of plasticizer in the photochromic layer was reduced compared to Examples (E1) to (E11), exhibited a slower fading rate but was still usable as light-controlling glass. It was found that the coloring rate and / or fading rate can be optimized by adjusting the amount of plasticizer depending on the application, etc.

[0154] In Comparative Example (EC1), a T-type photochromic material was used, but the transparent state did not return to normal even after several days in a room temperature environment (20 to 30° C.) It is presumed that, because no plasticizer was included in the photochromic layer in this Comparative Example, molecular isomerization was unlikely to occur, and the heat-induced fading reaction was extremely slow.

[0155] The laminated glass (glass laminate) obtained in Examples (E1) to (E10) and Comparative Example (EC2) all had a visible light transmittance (Tlv) of 80% or more before UV irradiation, indicating high transparency, but after UV irradiation, the visible light transmittance (Tdv) (measured value) was 60% or less and the visible light transmittance (Tdv) (theoretical value) was 50% or less, indicating a decrease in transparency. The laminated glass (glass laminate) obtained in Example (E11), because it contained a gray colored layer, had a visible light transmittance (Tlv) of 5 to 10% before UV irradiation, and after UV irradiation, the visible light transmittance (Tdv) (measured value) was 4% or less (3% or less) and the visible light transmittance (Tdv) (theoretical value) was 4% or less (3% or less), indicating a decrease in transparency. Representative transmission spectra (transparent and colored states before the weather resistance test, and transparent and colored states after the weather resistance test) of laminated glasses (glass laminates) obtained in some Examples and Comparative Examples are shown in FIGS. 6A to 6C.

[0156] The laminated glasses (glass laminates) obtained in Examples (E1) to (E11) all had a high performance retention rate of the photochromic material (PC performance retention rate) of 70% or more after a weather resistance test, and had significantly higher weather resistance than Comparative Example (EC2). The laminated glasses (glass laminates) obtained in Examples (E1), (E4) to (E6), and (E9) to (E11) had significantly higher weather resistance than Comparative Example (EC2), even though the total amount of ultraviolet screening agent contained in the laminated glass was the same.

[0157] In Examples (E1) to (E12), the UV-blocking layer is believed to have transmitted UV rays in a specific wavelength range with the amount of energy required to isomerize the photochromic material, while blocking at least a portion of UV rays (particularly UV rays in the short wavelength range (e.g., 360 nm or shorter)) that may have adverse effects on the photochromic material, such as deterioration and decomposition. Compared to a single-layer structure in which a UV absorber is added to the photochromic layer, the laminated structure of these Examples was able to reliably block at least a portion of the UV rays by the UV-blocking layer before they entered the photochromic layer, thereby more effectively suppressing deterioration of the photochromic material due to excessive UV irradiation. Furthermore, because the UV-blocking layer and the photochromic layer are independent of each other, the laminated structure is believed to have more effectively reduced the impact on the photochromic material of radicals that may be generated by the reaction between the UV-blocking agent and UV rays, compared to a single-layer structure in which a UV absorber is added to the photochromic layer. These combined effects are believed to have effectively improved weather resistance in these Examples.

[0158] The present invention is not limited to the above-described embodiments and examples, and appropriate design changes are possible without departing from the spirit of the present invention.

[0159] This application claims priority based on Japanese Patent Application No. 2024-131929, filed on August 8, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0160] FL1 to FL3, FL2A to FL2C, FL3A, FL3B Film laminate LB1, LB2 Laminate LM1, LM2 Laminated film 10 UV-shielding film 11 UV-shielding layer 20 Photochromic film 21 Photochromic layer 30 Separator film 31 Separator layer 40 Colored film 41 Colored layer 51, 52 Light-transmitting substrate

Claims

1. A film laminate comprising: an ultraviolet-shielding film having an ultraviolet-shielding layer that contains one or more thermoplastic resins and one or more ultraviolet-shielding agents and that blocks at least a portion of ultraviolet light; and a photochromic film having a photochromic layer that contains polyvinyl acetal, a plasticizer, and one or more photochromic materials that convert from a first isomer to a second isomer upon irradiation with light in a specific wavelength range, wherein the ultraviolet-shielding layer transmits at least a portion of the light in the specific wavelength range that isomerizes the photochromic material, and has an absorbance of 1.0 or greater at a wavelength of 360 nm.

2. The film laminate according to claim 1, wherein the ultraviolet blocking layer blocks a portion of ultraviolet light, and the photochromic material is transformed from the first isomer to the second isomer upon irradiation with ultraviolet light.

3. The film laminate according to claim 1 or 2, wherein the ultraviolet blocking layer contains one or more thermoplastic resins selected from the group consisting of polyvinyl acetal, ionomer, ethylene-vinyl acetate copolymer, cycloolefin polymer, polyester, and polyurethane.

4. The film laminate according to claim 1 or 2, wherein the photochromic layer contains one or more photochromic materials selected from the group consisting of triarylmethane compounds, stilbene compounds, azastilbene compounds, nitrone compounds, azobenzene compounds, quinone compounds, spirooxazine compounds, spironaphthoxazine compounds, hexaarylbiimidazole compounds, naphthopyran compounds, spiropyran compounds, fulgide compounds, diarylethene compounds, and inorganic photochromic materials.

5. The film laminate according to claim 1 or 2, wherein the photochromic layer comprises one or more T-type photochromic materials.

6. The film laminate according to claim 1 or 2, wherein the photochromic layer comprises one or more light stabilizers.

7. The film laminate according to claim 6, wherein the light stabilizer comprises one or more hindered amine light stabilizers.

8. The film laminate according to claim 1 or 2, wherein the ultraviolet blocking layer has an absorbance of 3.0 or less at a wavelength of 380 nm and an absorbance of 1.0 or less at a wavelength of 400 nm.

9. A film laminate according to claim 1 or 2, having a separator layer between the ultraviolet blocking layer and the photochromic layer, which prevents the ultraviolet blocking agent from migrating into the photochromic layer and the photochromic material from migrating into the ultraviolet blocking layer.

10. The film laminate according to claim 9, wherein the separator layer comprises one or more materials selected from the group consisting of polyester, polyvinyl alcohol, polycarbonate, polyvinyl acetal, ionomer, methacrylic resin, polyolefin, polyimide, and inorganic materials.

11. The film laminate according to claim 1 or 2, further comprising a coloring layer on the side of said photochromic layer opposite said ultraviolet blocking layer.

12. The film laminate according to claim 1 or 2, which comprises an infrared shielding layer that blocks at least a portion of infrared rays.

13. The film laminate according to claim 1 or 2, wherein the visible light transmittance (Tlv) of the film laminate before UV irradiation and the visible light transmittance (Tdv) of the film laminate after UV irradiation, when determined by the following method, satisfy the following formula (I): 1.5≦Tlv / Tdv≦20 (I) [Measurement Method] The transmission spectrum of the film laminate before UV irradiation is measured using a spectrophotometer at a measurement temperature of 23°C, a measurement wavelength range of 380 to 780 nm, and a scan speed of 1200 nm / min. From the obtained transmission spectrum, the visible light transmittance (Tlv) is determined in accordance with JIS R3212:2015 and JIS Z8722:2009. Next, the photochromic layer included in the film laminate is irradiated with simulated sunlight containing UV light from the UV-blocking layer side at an intensity of 1 sun for 60 seconds. 20 seconds after the end of the ultraviolet irradiation, the transmission spectrum of the film laminate after ultraviolet irradiation is measured in the same manner as before ultraviolet irradiation to determine the visible light transmittance (Tdv).

14. A laminated film comprising: an ultraviolet-shielding layer that contains one or more thermoplastic resins and one or more ultraviolet-shielding agents and that blocks at least a portion of ultraviolet light; and a photochromic layer that contains polyvinyl acetal, a plasticizer, and one or more photochromic materials that convert from a first isomer to a second isomer when irradiated with light in a specific wavelength range, wherein the ultraviolet-shielding layer transmits at least a portion of the light in the specific wavelength range that isomerizes the photochromic material, and has an absorbance of 1.0 or more at a wavelength of 360 nm.

15. A laminate comprising the laminate film according to claim 14 and a pair of light-transmitting substrates that sandwich the laminate film.

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