Photochromic film, resin film, and laminate

Abstract

The present disclosure provides: a photochromic film that includes a photochromic layer and is capable of more effectively improving weather resistance; a resin film; and a laminate.　A photochromic film (F1) according to the present disclosure includes a photochromic layer (21) containing: one or more thermoplastic resins; one or more photochromic materials; and one or more light stabilizers. The one or more light stabilizers include one or more NOR-type hindered amine-based light stabilizers.

Description

Photochromic film, resin film, and laminate

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

[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, such as vehicles and 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-control glass using such materials tends to lose performance when used for a long period of time in an environment where it is exposed to sunlight containing ultraviolet rays.

[0006] Examples of related art to the present disclosure include Patent Documents 1 to 4. Patent Documents 1 and 2 disclose interlayer films for laminated glass that contain a thermoplastic resin such as polyvinyl acetal, a photochromic material, and an ultraviolet absorber, and may also contain a plasticizer (claims 1 to 3 of Patent Document 1, and claims 1 and 2 of Patent Document 2). Patent Documents 1 and 2 describe that a light stabilizer can be added to the interlayer film for laminated glass. However, these documents do not disclose specific examples of light stabilizers or examples of manufacturing interlayer films for laminated glass using such light stabilizers. These documents do not disclose that interlayer films for laminated glass that include a resin layer containing a photochromic material and a specific light stabilizer have better weather resistance.

[0007] Patent Document 3 discloses an interlayer film for laminated glass that includes a thermochromic layer and a photochromic layer (Claim 1). In the "Examples" section of Patent Document 3, the thermochromic layer includes a thermochromic material and a triazine-based ultraviolet absorber (paragraph 0020). Patent Document 4 discloses a photochromic laminate that includes a photochromic layer and an ultraviolet absorbing layer, and the ultraviolet absorbing layer can block 30 to 90% of 350 nm light that enters the photochromic layer (Claim 1). Patent Documents 3 and 4 are silent about light stabilizers, and these documents do not disclose that an interlayer film for laminated glass that includes a photochromic material and a resin layer containing a specific light stabilizer has better weather resistance.

[0008] The techniques disclosed in Patent Documents 1 to 4 provide a certain 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 vehicles, buildings, etc. in an environment where sunlight containing ultraviolet rays is irradiated, it is preferable that laminated glass including a photochromic layer have higher weather resistance. As a result of intensive research, the present inventors have invented a photochromic film, a resin film, and a laminate that include a photochromic layer and can more effectively improve weather resistance compared to the techniques disclosed in Patent Documents 1 to 4.

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

[0010] The present disclosure provides the following photochromic films, resin films, and laminates: [1] A photochromic film comprising a photochromic layer containing one or more thermoplastic resins, one or more photochromic materials, and one or more light stabilizers, wherein the light stabilizers include one or more NOR-type hindered amine light stabilizers.

[0011] [2] The photochromic film of [1], wherein the photochromic material is converted from a first isomer to a second isomer upon irradiation with light in a specific wavelength range. [3] The photochromic film of [2], wherein the photochromic material is converted from the first isomer to the second isomer upon irradiation with ultraviolet light. [4] The photochromic film of any of [1] to [3], wherein the photochromic layer further contains one or more plasticizers.

[0012] [5] The photochromic film according to any one of [1] to [4], wherein the photochromic layer contains one or more thermoplastic resins selected from the group consisting of polyvinyl acetal, ionomer, ethylene-vinyl acetate copolymer, cycloolefin polymer, and polyurethane.

[0013] [6] The photochromic film of any one of [1] to [5], 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. [7] The photochromic film of any one of [1] to [6], wherein the photochromic layer contains one or more T-type photochromic materials. [8] The photochromic film of any one of [1] to [7], wherein the photochromic layer contains one or more ultraviolet blocking agents that block at least a portion of ultraviolet light.

[0014] [9] A photochromic film according to any one of [1] to [8], wherein when the visible light transmittance (Tlv) before UV irradiation and the visible light transmittance (Tdv) 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 photochromic film before UV irradiation is measured using a spectrophotometer 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 obtained transmission spectrum, the visible light transmittance (Tlv) is determined in accordance with JIS R3212 and JIS Z8722. Next, the photochromic film is irradiated with simulated sunlight containing UV light at an intensity of 1 sun for 60 seconds. Twenty seconds after the end of UV irradiation, the transmission spectrum of the photochromic film after UV irradiation is measured in the same manner as before UV irradiation, and the visible light transmittance (Tdv) is determined.

[0015]

[10] A resin film comprising a photochromic layer containing one or more thermoplastic resins, one or more photochromic materials, and one or more light stabilizers, wherein the light stabilizers include one or more NOR-type hindered amine light stabilizers.

[0016]

[11] A laminate comprising the resin film of

[10] and a pair of light-transmitting substrates that sandwich the resin film.

[0017] According to the present disclosure, it is possible to provide a photochromic film, a resin film, and a laminate that can more effectively improve weather resistance.

[0018] 1 is a schematic cross-sectional view of a photochromic film according to an embodiment of the present invention; 2 is a schematic cross-sectional view of a laminate according to an embodiment of the present invention; 3 is an absorption spectrum of the ultraviolet screening agent and glass plate alone used in the [Examples] section; 4 is a transmission spectrum of the laminated glass (glass laminate) obtained in Example (E11) (transparent state and colored state before weathering test, and transparent state and colored state after weathering test); 5 is a transmission spectrum of the laminated glass (glass laminate) obtained in Example (E12) (transparent state and colored state before weathering test, and transparent state and colored state after weathering test); 6 is a transmission spectrum of the laminated glass (glass laminate) obtained in Comparative Example (EC11) (transparent state and colored state before weathering test, and transparent state and colored state after weathering test).

[0019] 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.

[0020] [Photochromic Film] The photochromic film of the present disclosure includes a photochromic layer containing one or more thermoplastic resins, one or more photochromic materials, and one or more light stabilizers. In the photochromic film of the present disclosure, the light stabilizer includes one or more NOR-type hindered amine light stabilizers. The photochromic layer may have a single-layer structure or a laminate structure. The photochromic layer may optionally contain one or more plasticizers. The photochromic layer may optionally contain one or more other additives. The photochromic film may include one or more optional layers other than the photochromic layer.

[0021] When irradiated with light in a specific wavelength range (e.g., ultraviolet light), the photochromic material undergoes a molecular structure change from a first isomer to a second isomer without changing its molecular weight, thereby changing its optical properties. 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 or lighting device.

[0022] 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.

[0023] The photochromic layer may contain one or more ultraviolet blocking agents that block at least a portion of ultraviolet light. In a preferred embodiment, the ultraviolet blocking agent transmits at least a portion of light in a specific wavelength range that causes the photochromic material to isomerize from a first isomer to a second isomer. In a preferred embodiment, the ultraviolet blocking agent blocks at least a portion of ultraviolet light and has an absorbance of 1.0 or greater at a wavelength of 360 nm.

[0024] 1 is a schematic cross-sectional view of a photochromic film according to one embodiment of the present invention. The photochromic film F1 of this embodiment is a film having a single layer structure or a laminate structure including a photochromic layer 21.

[0025] The film-forming method for the photochromic film F1 of the above embodiment is not particularly limited, and examples thereof include extrusion, calendaring, pressing, casting, and inflation methods. Among these, the extrusion method using an extruder equipped with a T-die (also referred to as the T-die method) is preferred. The T-die method will be described below. A resin material containing one or more thermoplastic resins (preferably polyvinyl acetal and ionomer, etc.); a combination of one or more photochromic materials and one or more light stabilizers; optionally 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 with a wide discharge opening. To remove foreign matter, the molten resin is preferably melt-filtered using a filter before extrusion. Film-forming using the melt-filtered molten resin results in a film with fewer defects caused by foreign matter and gels. 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 the T-die is cooled using multiple cooling rolls, and the film obtained after cooling is taken up by a take-up roll. The above steps of extrusion, cooling, and take-up are carried out continuously.

[0026] (Other Functions or Other Functional Layers) In the photochromic film of the present disclosure, the photochromic layer may have other functions in addition to the photochromic function and the UV-shielding function that may be provided as needed. The photochromic film of the present disclosure may have a functional layer having one or more other functions in addition to the photochromic layer having the photochromic function and the UV-shielding function as needed. Other functions that the photochromic 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 to improve adhesion between the photochromic film of the present disclosure and a translucent substrate, and a design function.

[0027] The photochromic film of the present disclosure may include, for example, an infrared-shielding layer that blocks at least a portion of infrared rays. In this case, the photochromic layer may contain one or more infrared-shielding agents and serve as the infrared-shielding layer. Alternatively or additionally, the other functional layer may contain one or more infrared-shielding agents or may be an infrared-shielding film, serving as the infrared-shielding layer. The infrared-shielding layer may be either an infrared-absorbing type or an infrared-reflecting type, with the infrared-reflecting type being preferred.

[0028] [Resin Film] The resin film of the present disclosure includes a photochromic layer containing one or more thermoplastic resins, one or more photochromic materials, and one or more light stabilizers. In the resin film of the present disclosure, the light stabilizer includes one or more NOR-type hindered amine light stabilizers. The photochromic layer can include one or more ultraviolet blocking agents that block at least a portion of ultraviolet light. The resin film of the present disclosure can include one or more optional layers other than the photochromic layer. Preferred embodiments of the photochromic layer are the same as the photochromic layer included in the photochromic film of the present disclosure described above. One embodiment of the resin film of the present disclosure is a laminated glass interlayer.

[0029] [Laminate] The laminate of the present disclosure includes the resin film of the present disclosure and a pair of light-transmitting substrates that sandwich the resin film. One embodiment of the laminate of the present disclosure is laminated glass.

[0030] 2 shows a schematic cross-sectional view of a laminate according to one embodiment of the present invention. In this figure, the same components as those in FIG. 1 are designated by the same reference numerals, and their explanations will be omitted. The laminate LB1 of this embodiment has a resin film M1 including a photochromic layer 21, and a pair of light-transmitting substrates 41 and 42 that sandwich the resin film M1.

[0031] The laminate of the present disclosure can be produced by stacking multiple components including a first light-transmitting substrate, the photochromic film 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 performed 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. From the viewpoints of degassing properties and inter-component bonding, preliminary compression bonding methods include degassing methods under reduced pressure, such as the vacuum bag method, vacuum ring method, and vacuum laminator method; degassing methods using nip rolls; and compression methods at high temperatures. Among these, degassing methods 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 heatable and evacuable chamber. 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.

[0032] In the photochromic film, resin film, and laminate of the present disclosure, a specific light stabilizer (specifically, a NOR-type hindered amine light stabilizer (NOR-type HALS)) added to the photochromic layer can capture radicals that may be generated by the isomerization reaction of the photochromic material, thereby effectively improving weather resistance.

[0033] In the photochromic film, resin film, and laminate of the present disclosure, the ultraviolet ray blocking agent that can be contained in the photochromic layer preferably transmits at least a portion of light in a specific wavelength range necessary for isomerization of the photochromic material from a first isomer to a second isomer, while blocking at least a portion of ultraviolet rays that may have adverse effects on the photochromic material, such as deterioration and decomposition. For example, the photochromic material can be converted from the first isomer to the second isomer by ultraviolet irradiation. In this case, the ultraviolet ray blocking agent preferably transmits ultraviolet rays in a specific wavelength range with the energy amount necessary for isomerization of the photochromic material, while blocking at least a portion of ultraviolet rays (particularly ultraviolet rays in a relatively short wavelength range (e.g., 360 nm or shorter)) that may have adverse effects on the photochromic material, such as deterioration and decomposition.

[0034] (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.

[0035] 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.).

[0036] 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" Examples of suitable photochromic films include "Reversacol Blue" and "Reversacol Volcanic Grey" (both manufactured by James Robinson Specialty Ingredients). Among the above, the Reversacol series manufactured by James Robinson Specialty Ingredients is preferred because the photochromic film of the present disclosure is likely to achieve both weather resistance and photochromic performance.

[0037] 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."

[0038] 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 in a room temperature environment (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. Once irradiation with light in the specific wavelength range is stopped, they can return from the colored state to a transparent state without any special treatment upon exposure to a room temperature environment (20-30°C), heat at a temperature below room temperature, or heat at a temperature above room temperature. 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.

[0039] The photochromic film of the present disclosure preferably satisfies the following formula (I) when the visible light transmittance (Tlv) (measured value) before UV irradiation and the visible light transmittance (Tdv) (measured value) after UV irradiation are determined using the following method: 1.5≦Tlv (measured value) / Tdv (measured value)≦20 (I) [Measurement Method] The transmission spectrum of the photochromic film before UV irradiation is measured using a spectrophotometer 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 obtained transmission spectrum, the visible light transmittance (Tlv) (measured value) is determined in accordance with JIS R3212 and JIS Z8722. Next, the photochromic film is irradiated with simulated sunlight containing UV light at an intensity of 1 sun for 60 seconds. 20 seconds after the end of the UV irradiation, the transmission spectrum of the photochromic film after UV irradiation is measured in the same manner as before UV irradiation to determine the visible light transmittance (Tdv) (measured value).

[0040] In the photochromic film 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.

[0041] 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 (measured value) / Tdv (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 and 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.

[0042] (Light Stabilizer) The light stabilizer contained in the photochromic layer can capture and detoxify radicals (specifically, alkyl radicals, peroxide radicals, etc.) generated by heat and / or ultraviolet light. In the present disclosure, the light stabilizer contained in the photochromic layer includes one or more 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 organic group such as 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 an alkyl group, an aralkyl group, and an aryl group. The alkyl group may be linear, branched, or cyclic. Hindered amine light stabilizers other than NOR type, such as NH type and NR type, are also collectively referred to as "non-NOR type hindered amine light stabilizers."

[0043] In the present disclosure, the light stabilizer contained in the photochromic layer includes one or more NOR-type hindered amine-based light stabilizers (NOR-type HALS), and one or more non-NOR-type hindered amine-based 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. NOR-type HALS having an alkoxyimino group is preferred. Examples of NOR-type HALS include the NOR-type HALS disclosed in JP-A-2002-507238, WO-A-2005 / 082852, and WO-A-2008 / 003605.

[0044] 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'-hexamethylenediamine an oligomeric compound which is the condensation product of hexamethylenebis(amino-2,2,6,6-tetramethylpiperidine) with 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; and 4,4'-hexamethylenebis(amino-2,2,6,6-tetramethylpiperidine) with 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)butylamino]-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). Examples of the compound (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.

[0045] 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.

[0046] Preferred commercially available NOR-type HALS include "Tinuvin XT 850 FF," "Flamestab NOR 116 FF," "Tinuvin 123," and "Tinuvin 152" manufactured by BASF, and "ADEKA STAB LA-81" manufactured by ADEKA Corporation. "Tinuvin 123" and "Tinuvin 152" are particularly preferred because of their high fluidity and excellent radical scavenging ability.

[0047] The content of NOR-type hindered amine light stabilizers (NOR-type HALS) in the photochromic layer (total amount if 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 thermoplastic resin and plasticizer combined. 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. If the content of NOR-type HALS is equal to or greater than the lower limit, the radical scavenging function of the NOR-type HALS can be favorably obtained, and if 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 NOR-type HALS can be suppressed.

[0048] (UV Blocking Agent) The UV blocking agent that can be contained in the photochromic layer can be one or more known UV blocking agents. The UV blocking agent may be either a UV absorbing type or a UV reflecting type, and is preferably a UV absorbing type. Examples of the UV absorbing agent include benzophenone-based UV absorbers, benzotriazole-based UV absorbers, triazine-based UV absorbers, benzodithiol-based UV absorbers, azomethine-based UV absorbers, and indole-based UV absorbers.

[0049] 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).

[0050] 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.

[0051] 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).

[0052] 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.

[0053] 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 are more likely to provide an ultraviolet shielding function with absorbances at 360 nm, 380 nm, and 400 nm within preferred ranges, and the photochromic layer is more likely to achieve both weather resistance and photochromic performance.

[0054] The content of the UV blocking agent in the photochromic layer (the total amount if multiple types are used unless otherwise specified) is not particularly limited and can be determined depending on the type of UV blocking agent and the thickness of the photochromic layer so that the absorbance at 360 nm, 380 nm, and 400 nm falls within a preferred range. The content of the UV blocking agent 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 and 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.

[0055] (Thermoplastic Resin) The thermoplastic resin contained in the photochromic layer may be one or more known thermoplastic resins. The photochromic layer preferably contains one or more thermoplastic resins used as materials for laminated glass interlayers. Specifically, the photochromic preferably contains one or more thermoplastic resins selected from the group consisting of polyvinyl acetal, ionomer, ethylene-vinyl acetate copolymer, cycloolefin polymer, and polyurethane, and more preferably contains polyvinyl acetal.

[0056] The content of the thermoplastic resin in the photochromic layer (total amount when multiple types are used unless otherwise specified) is not particularly limited, but is preferably 60 to 100% by mass. The lower limit is more preferably 65% ​​by mass, and particularly preferably 70% by mass. The upper limit is more preferably 99% 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.

[0057] <Polyvinyl acetal> Polyvinyl acetal is a resin produced by acetalization of a polyvinyl alcohol-based resin such as polyvinyl alcohol or an ethylene-vinyl alcohol copolymer. 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 polymerization degree, acetalization degree, vinyl acetate unit content, vinyl alcohol unit content, ethylene unit content, molecular weight of aldehyde used in acetalization, and chain length.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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-butylaldehyde is preferred from the viewpoint of facilitating the production of polyvinyl acetal having suitable breaking energy. The amount of n-butylaldehyde 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.

[0062] 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.

[0063] The viscosity-average degree of polymerization of polyvinyl alcohol can be measured, for example, in accordance with JIS K 6726 "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 photochromic layer contains two or more polyvinyl acetals, it is preferred that the viscosity-average degree of polymerization of at least one of the polyvinyl acetals be within the above-mentioned range.

[0064] 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.

[0065] 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 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 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.

[0066] 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. An acetalization degree within the above range improves the mechanical strength of the polyvinyl acetal and its compatibility with plasticizers added as needed. When the photochromic layer contains two or more polyvinyl acetals, it is preferable that the degree of acetalization of at least one of the polyvinyl acetals be within the above range.

[0067] The hydroxyl group content of the polyvinyl acetal (the amount of hydroxyl groups remaining after acetal modification) is not particularly limited, but 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 of the polyvinyl acetal main chain. When sound insulation performance is desired in the 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 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.

[0068] 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, by JIS K 6728 "Testing Methods for Polyvinyl Butyral" or 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.

[0069] 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 adjusted to 10% by mass using a mixed solvent obtained by mixing toluene and ethanol in a mass ratio of 1:1 as the solvent. The viscosity of the polyvinyl acetal contained in the photochromic layer is preferably greater than 200 mPa·s, more preferably 210 mPa·s or more, more preferably 220 mPa·s or more, even more preferably 230 mPa·s or more, particularly preferably 240 mPa·s or more, and most preferably 265 mPa·s or more. If 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 likely to be suppressed. By using a polyvinyl acetal produced using a polyvinyl alcohol having a relatively high viscosity average polymerization degree 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. When the photochromic layer contains two or more polyvinyl acetals, the viscosity is the viscosity of a mixture of these. From the viewpoint of good film-forming properties, the viscosity 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.

[0070] The peak top molecular weight of the polyvinyl acetal contained in 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 materials, 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 formability and favorable film properties (e.g., thermocompression bonding suitability, creep resistance, and elongation at break) are likely to be obtained.

[0071] The molecular weight distribution of the polyvinyl acetal contained in 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 acetalized products of two or more 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 rupture 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 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.

[0072] The photochromic layer preferably contains 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.

[0073] <Ionomer> An ionomer 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.

[0074] (Plasticizer) The plasticizer that can be contained in the photochromic layer is not particularly limited, and one or more of the following examples (Pa) to (Pe) can 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).

[0075] (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.

[0076] (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.

[0077] The plasticizer is preferably one that does not impair the physical properties of the photochromic layer. 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.

[0078] 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 viewpoint of film-forming properties, etc., 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 1 part by mass, even more preferably 5 parts by mass, even more preferably 10 parts by mass, still 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. When the photochromic layer contains an appropriate amount of plasticizer, the coloring rate and fading rate of the photochromic material become good, and this is preferred.

[0079] (Other Additives) The photochromic layer may contain one or more other additives other than those described above, if necessary. Examples of other additives include antioxidants; peroxide decomposers, singlet oxygen quenchers, triplet quenchers; adhesion modifiers; colorants such as 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 properties); calcined silica; surfactants, etc.

[0080] Examples of antioxidants include phenol-based, phosphorus-based, lactone-based, and hydroxyl-based antioxidants. Among these, phenol-based antioxidants, phosphorus-based antioxidants, and combinations thereof are preferred. Examples of phenol-based 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, pentaerythritol, methyl methyl acrylate, methyl acrylate copolymer, methyl acrylate copolymer, methyl acrylate copolymer, methyl acrylate copolymer, methyl acrylate copolymer, methyl acrylate copolymer, methyl acrylate copolymer 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).

[0081] 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].

[0082] The adhesive strength adjuster may include magnesium acetate tetrahydrate.

[0083] (Total Thickness, Thickness of Each Layer) The total thickness and thickness of each layer of the photochromic film of the present disclosure are not particularly limited and can be designed appropriately. The total thickness (T Ｆ ) 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 photochromic film is within the above range, excellent penetration resistance is easily obtained.

[0084] When the photochromic film of the present disclosure includes a photochromic layer and other functional layers, the preferred thickness of each layer is as follows: The thickness (T ＰＣ) is not particularly limited, and is preferably 50 to 800 μm from the viewpoint of exhibiting photochromic function. The lower limit is more preferably 100 μm, even more preferably 150 μm, still 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. The thickness (T ＯＬ ) is not particularly limited, and is preferably 10 to 500 μm from the viewpoint of ensuring the function 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, and most preferably 80 μm. The upper limit is more preferably 400 μm, particularly preferably 300 μm, and most preferably 200 μm.

[0085] The total thickness of the resin film of the present disclosure is the total thickness (T Ｆ ) tends to be smaller during the thermocompression bonding process.

[0086] (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.

[0087] As described above, according to the present disclosure, it is possible to provide a photochromic film, a resin film, and a laminate that can more effectively improve weather resistance.

[0088] [Applications] The laminate of the present disclosure is suitable for applications such as window glass for vehicles such as trains, electric trains, and automobiles, and for mobile bodies such as 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 resin film of the present disclosure is suitable as an interlayer film for window glass for vehicles or buildings. The photochromic film of the present disclosure is suitable as a material for the above interlayer film.

[0089] 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 Screening Agent or Glass Plate Alone) 0.2 parts by mass of a triazine-based UV absorber (UVA1) was added to 72.5 parts by mass of polyvinyl butyral (PVB1), and the mixture was 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 film for measuring the absorbance of the UV screening agent. The absorption spectrum of the film for measuring the absorbance of the UV screening agent or the glass plate (G1) alone was measured using a spectrophotometer (Hitachi High-Tech Corporation, "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. The absorption spectra of the UV screening agent (UVA1) and the glass plate (G1) alone are shown in Figure 3.

[0090] (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 the 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 obtained transmission spectrum, the visible light transmittance (Tlv) (actual measured value) was calculated in accordance with JIS R3212 and JIS Z8722. In addition, the transmittance (Tlv) at the maximum absorption wavelength (specifically, 580 nm) was also calculated. ５８０ ) (actual measured value) was calculated.

[0091] Next, using a light guide irradiation type AM1.5G pseudo-sunlight source ("Solar Simulator HAL-320" manufactured by Asahi Spectroscopy Co., Ltd.), the laminated glass (glass laminate) was irradiated with pseudo-sunlight containing ultraviolet (UV) rays at an intensity of 1 sun for 60 seconds to color the photochromic layer.

[0092] 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.

[0093] When ultraviolet (UV) irradiation of the T-type photochromic material is stopped, the color returns to its original state. 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.

[0094] 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.

[0095] 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 3, 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).

[0096] (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. Next, the laminated glass (glass laminate) was irradiated with ultraviolet (UV) rays in the same manner as before the weathering test to color the photochromic layer. Next, the transmission spectrum of the laminated glass (glass laminate) in a colorless and transparent state (light state) after UV 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 Next, the transmission spectrum of the laminated glass (glass laminate) in the colored state (dark state) after ultraviolet 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 ５８０ Since 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).

[0097] [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.

[0098] <Plasticizer> (3G8) Triethylene glycol-bis-(2-ethylhexanoate).

[0099] <UV Screening Agent> (UVA1) Triazine-based UV absorber ("Tinuvin (registered trademark) 479" manufactured by BASF).

[0100] <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.

[0101] <Antioxidant> (AO1) Hindered phenol-based antioxidant ("Irganox 245" manufactured by BASF).

[0102] <Light stabilizers> (HALS1) NOR type hindered amine light stabilizer (manufactured by BASF Corporation, "Tinuvin (registered trademark) 123"), (HALS2) NOR type hindered amine light stabilizer (manufactured by BASF Corporation, "Tinuvin (registered trademark) 152"), (HALS3) non-NOR type hindered amine light stabilizer (manufactured by BASF Corporation, "Tinuvin (registered trademark) 111 FDL").

[0103] <Adhesion modifier> (ADH1) Magnesium acetate tetrahydrate ((CH ３ COO) ２ Mg 4H ２ O).

[0104] Example (E11) (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 obtained resin composition was press-molded to obtain a photochromic film (PC film) having a single layer structure consisting of a photochromic layer (PC layer) measuring 5 cm x 5 cm and having a thickness of 800 μm.

[0105] (Preparation of Laminated Glass (Glass Laminate)) The obtained photochromic film (PC) was sandwiched between a pair of glass plates (G1) (2 mm thick float glass), and the obtained pre-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. Then, while maintaining the reduced pressure, the temperature was raised to 100°C 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. The pre-pressure bonded body was then placed in an autoclave and heated under pressure at 140°C and 1.2 MPa for 30 minutes (main pressure bonding). In this way, a laminated glass (glass laminate) (LB) including a single-layer interlayer film composed of a photochromic layer (PC layer) was obtained. The composition and thickness of the interlayer film are shown in Table 1. In the table, "pts." means parts by mass.

[0106] [Example (E12) and Comparative Example (EC11)] A photochromic film (PC film) and a laminated glass (glass laminate) (LB) were obtained in the same manner as in Example (E11), except that the type of light stabilizer was changed. The composition and thickness of the interlayer film are shown in Table 1.

[0107]

[0108] [Summary of Results] In the laminated glass (glass laminate) obtained in Examples (E11) and (E22), a NOR hindered amine light stabilizer (NOR HALS) was added to the photochromic layer. In the laminated glass (glass laminate) obtained in Comparative Example (EC11), a non-NOR hindered amine light stabilizer (non-NOR HALS) was added to the photochromic layer. The laminated glass (glass laminate) obtained in these Examples and Comparative Examples changed in transmission spectrum upon ultraviolet irradiation, changing from a transparent state to a colored state. In these Examples and Comparative Examples, because a T-type photochromic material was used, when ultraviolet irradiation was stopped, the colored state naturally returned to a transparent state due to heat in a room temperature environment (20 to 30°C) without any special treatment.

[0109] The laminated glass (glass laminate) obtained in these Examples and Comparative Examples all had a visible light transmittance (Tlv) of 85% or more before UV irradiation, indicating high transparency, but after UV irradiation, the visible light transmittance (Tdv) (measured value) was 30% or less and the visible light transmittance (Tdv) (theoretical value) was 20% or less, indicating a decrease in transparency. The laminated glass (glass laminate) obtained in these Examples and Comparative Examples all showed a greater decrease in visible light transmittance after UV irradiation, and a greater change in appearance after UV irradiation compared to before UV irradiation. The transmission spectra (transparent and colored states before weathering test, and transparent and colored states after weathering test) of the laminated glass (glass laminate) obtained in each Example are shown in Figures 4A to 4C.

[0110] The laminated glasses (glass laminates) obtained in Examples (E11) and (E12) both had significantly higher weather resistance in terms of the performance retention rate of the photochromic material (PC performance retention rate) after a weather resistance test than Comparative Example (EC11). In these Examples, it is believed that the specific light stabilizer (specifically, a NOR-type hindered amine light stabilizer (NOR-type HALS)) added to the photochromic layer effectively captured radicals that could be generated by the isomerization reaction of the photochromic material, thereby contributing to improved weather resistance.

[0111] 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.

[0112] This application claims priority based on Japanese Patent Application No. 2024-072037, filed April 26, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0113] F1 Photochromic film LB1 Laminate M1 Resin film 21 Photochromic layer 41, 42 Light-transmitting substrate

Claims

1. A photochromic film comprising a photochromic layer containing one or more thermoplastic resins, one or more photochromic materials, and one or more light stabilizers, wherein the light stabilizers include one or more NOR-type hindered amine light stabilizers.

2. The photochromic film according to claim 1, wherein the photochromic material is transformed from a first isomer to a second isomer upon irradiation with light in a specific wavelength range.

3. The photochromic film according to claim 2, wherein the photochromic material is transformed from the first isomer to the second isomer upon irradiation with ultraviolet light.

4. The photochromic film of claim 1 or 2, wherein the photochromic layer further comprises one or more plasticizers.

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

6. The photochromic film 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.

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

8. The photochromic film according to claim 1 or 2, wherein the photochromic layer contains one or more ultraviolet blocking agents that block at least a portion of ultraviolet light.

9. The photochromic film according to claim 1 or 2, wherein the visible light transmittance (Tlv) before UV irradiation and the visible light transmittance (Tdv) after UV irradiation satisfy the following formula (I): 1.5≦Tlv / Tdv≦20 (I) [Measurement Method] The transmission spectrum of the photochromic film before UV irradiation is measured using a spectrophotometer at 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 obtained transmission spectrum, the visible light transmittance (Tlv) is determined in accordance with JIS R3212 and JIS Z8722. Next, the photochromic film is irradiated with simulated sunlight containing UV light at an intensity of 1 sun for 60 seconds. Twenty seconds after the end of UV irradiation, the transmission spectrum of the photochromic film after UV irradiation is measured in the same manner as before UV irradiation, and the visible light transmittance (Tdv) is determined.

10. A resin film comprising a photochromic layer containing one or more thermoplastic resins, one or more photochromic materials, and one or more light stabilizers, wherein the light stabilizers include one or more NOR-type hindered amine light stabilizers.

11. A laminate comprising the resin film according to claim 10 and a pair of light-transmitting substrates that sandwich the resin film.

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