Intermediate film for laminated glass and laminated glass

Abstract

Provided is an intermediate film for laminated glass, the film being capable of suppressing the occurrence of yellowing and improving adhesion between the intermediate film and a laminated glass member.　The intermediate film for laminated glass according to the present invention has a single-layer structure or a structure having two or more layers, and includes an ultraviolet ray absorber represented by formula (X) and a metal salt.　In formula (X), R1 represents an arbitrary group, and R2to R8 each represent a hydrogen atom, an atom other than a hydrogen atom, or an arbitrary group.

Description

Interlayer film for laminated glass and laminated glass

[0001] The present invention relates to an interlayer film for laminated glass used to obtain laminated glass. The present invention also relates to laminated glass.

[0002] Laminated glass is excellent in safety because it generates only a small amount of glass fragments even when broken by external impact. For this reason, laminated glass is widely used in automobiles, railway vehicles, aircraft, ships, buildings, etc. Laminated glass is manufactured by sandwiching an interlayer film between a pair of glass sheets.

[0003] In order to suppress transmission of ultraviolet light, an interlayer film containing an ultraviolet absorber having a benzotriazole skeleton is sometimes used (for example, see Patent Document 1 below). In addition, in laminated glass, an interlayer film containing a metal salt is sometimes used to increase the adhesive strength between the interlayer film and the laminated glass member (such as glass plates).

[0004] WO2015 / 088866A1

[0005] In order to suppress the transmission of ultraviolet rays and increase the adhesive strength between the interlayer film and the laminated glass member, it is conceivable to use an interlayer film containing both an ultraviolet absorber and a metal salt. However, the combination of a conventional ultraviolet absorber having a benzotriazole skeleton and a metal salt can cause yellowing of the interlayer film. While reducing the content of the metal salt can suppress yellowing to some extent, the adhesive strength between the interlayer film and the laminated glass member decreases.

[0006] Therefore, with conventional interlayer films containing a metal salt and an ultraviolet absorber having a benzotriazole skeleton, it is difficult to achieve both the effects of reducing yellowing and increasing the adhesive strength between the interlayer film and the laminated glass member.

[0007] An object of the present invention is to provide an interlayer film for laminated glass that is less susceptible to yellowing and that can increase the adhesive strength between the interlayer film and a laminated glass member. Another object of the present invention is to provide laminated glass using the interlayer film for laminated glass.

[0008] According to a broad aspect of the present invention, there is provided an interlayer film for laminated glass (hereinafter sometimes referred to as an interlayer film) having a single-layer structure or a two or more-layer structure, the interlayer film for laminated glass comprising an ultraviolet absorber represented by formula (X) below and a metal salt:

[0009]

[0010] In the formula (X), R １ represents any group, and R ２ ~R ８ represents a hydrogen atom, an atom other than a hydrogen atom, or an arbitrary group.

[0011] In a specific aspect of the interlayer film according to the present invention, the interlayer film includes a layer containing the ultraviolet absorber and the metal salt.

[0012] In a specific aspect of the interlayer film according to the present invention, in the formula (X), R １ is an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group.

[0013] In a specific aspect of the interlayer film according to the present invention, the molecular weight of the ultraviolet absorber is 355 or more.

[0014] In a specific aspect of the interlayer film according to the present invention, the ultraviolet absorber includes an ultraviolet absorber represented by the following formula (X11), the following formula (X12), or the following formula (X13):

[0015]

[0016]

[0017]

[0018] In a specific aspect of the interlayer film according to the present invention, the metal salt includes an alkali metal salt or an alkaline earth metal salt.

[0019] In a specific aspect of the interlayer film according to the present invention, the metal salt includes a magnesium salt of an organic acid having a branched structure.

[0020] In a specific aspect of the interlayer film according to the present invention, the metal salt is a metal salt other than a magnesium salt of an organic acid having a branched structure, and includes a metal salt of an organic acid having 2 to 8 carbon atoms.

[0021] In a specific aspect of the interlayer film according to the present invention, the interlayer film is an interlayer film for laminated glass having a structure of two or more layers, and includes a first layer and a second layer disposed on a first surface side of the first layer.

[0022] In a specific aspect of the interlayer film according to the present invention, the second layer is a surface layer of the interlayer film, and the second layer contains the ultraviolet absorber and the metal salt.

[0023] In a specific aspect of the interlayer film according to the present invention, the interlayer film is an interlayer film for laminated glass having a structure of three or more layers, and includes a third layer disposed on a second surface side of the first layer opposite the first surface.

[0024] In a specific aspect of the interlayer film according to the present invention, the third layer is a surface layer of the interlayer film, and the third layer contains the ultraviolet absorber and the metal salt.

[0025] In a specific aspect of the interlayer film according to the present invention, the interlayer film includes a layer containing the ultraviolet absorber and the metal salt, and in the layer containing the ultraviolet absorber and the metal salt, the weight ratio of the content of the metal contained in the metal salt to the content of the ultraviolet absorber is 4 or more and 50 or less.

[0026] In a specific aspect of the interlayer film according to the present invention, the maximum value of the transmittance of the interlayer film in the wavelength range of 300 nm or more and 350 nm or less is 0.1% or less.

[0027] In a specific aspect of the interlayer film according to the present invention, the interlayer film has an ultraviolet transmittance Tuv of 0.5% or less.

[0028] In a specific aspect of the interlayer film according to the present invention, the interlayer film has a transmittance at a wavelength of 400 nm of 1.5% or more.

[0029] In a specific aspect of the interlayer film according to the present invention, the absolute value of the difference between the yellow index YI of the interlayer film and the yellow index YI of a comparative interlayer film that has the same layer structure and thickness as the interlayer film but does not contain a metal salt is 0.1 or less.

[0030] According to a broad aspect of the present invention, there is provided laminated glass comprising a first laminated glass element, a second laminated glass element, and the above-described interlayer film for laminated glass, with the interlayer film for laminated glass disposed between the first laminated glass element and the second laminated glass element.

[0031] The interlayer film for laminated glass according to the present invention has a single-layer structure or a two or more-layer structure. The interlayer film for laminated glass according to the present invention contains an ultraviolet absorber represented by formula (X) and a metal salt. Because the interlayer film for laminated glass according to the present invention has the above-described structure, it is possible to reduce yellowing and increase the adhesive strength between the interlayer film and the laminated glass member.

[0032] Fig. 1 is a cross-sectional view schematically showing an interlayer film for laminated glass according to a first embodiment of the present invention. Fig. 2 is a cross-sectional view schematically showing an interlayer film for laminated glass according to a second embodiment of the present invention. Fig. 3 is a cross-sectional view schematically showing an example of laminated glass using the interlayer film for laminated glass shown in Fig. 1. Fig. 4 is a cross-sectional view schematically showing an example of laminated glass using the interlayer film for laminated glass shown in Fig. 2.

[0033] The present invention will be described in detail below.

[0034] (Interlayer Film for Laminated Glass) The interlayer film for laminated glass according to the present invention (sometimes abbreviated as "interlayer film" in this specification) is used in laminated glass.

[0035] The interlayer film of the present invention has a single-layer structure or a two or more-layer structure. The interlayer film of the present invention may have a single-layer structure or a two or more-layer structure. The interlayer film of the present invention may have a two-layer structure, a two or more-layer structure, a three-layer structure, or a three or more-layer structure. The interlayer film of the present invention may include only a first layer. The interlayer film of the present invention may include a first layer and a second layer disposed on a first surface side of the first layer. The interlayer film of the present invention may include a first layer, a second layer disposed on a first surface side of the first layer, and a third layer disposed on a second surface side of the first layer opposite the first surface. The interlayer film of the present invention may be a single-layer interlayer film or a multi-layer interlayer film. The structure of the interlayer film of the present invention may be partially different. For example, the interlayer film of the present invention may have a portion having a single-layer structure and a portion having a multi-layer structure.

[0036] The interlayer film according to the present invention contains an ultraviolet absorber represented by the following formula (X) (sometimes abbreviated herein as "ultraviolet absorber (X)") and a metal salt. Thus, the interlayer film according to the present invention contains the ultraviolet absorber (X) and a metal salt.

[0037]

[0038] In the above formula (X), R １ represents any group, and R ２ ~R ８ represents a hydrogen atom, an atom other than a hydrogen atom, or an arbitrary group.

[0039] Conventional combinations of UV absorbers having a benzotriazole skeleton and metal salts can cause yellowing of the interlayer film. Furthermore, UV absorbers having a skeleton in which a hydroxyl group is directly bonded to a benzene ring (phenol skeleton) are sometimes used as UV absorbers having a benzotriazole skeleton. The present inventors have discovered that the yellowing of the interlayer film is caused by a reaction between the hydroxyl group of the UV absorber having a benzotriazole skeleton and a metal salt. While reducing the content of the metal salt can suppress yellowing to some extent, the adhesive strength between the interlayer film and the laminated glass member decreases.

[0040] In contrast, in the interlayer film according to the present invention, the benzotriazole skeleton is bonded to a specific position (R １ Since the ultraviolet absorber (X) having an optional group at the position (X) is used, it is possible to reduce the reactivity of the hydroxyl group directly bonded to the benzene ring with the metal salt. As a result, it is possible to make the interlayer film less susceptible to yellowing. Furthermore, since the interlayer film according to the present invention uses a metal salt, it is possible to increase the adhesive strength between the interlayer film and the laminated glass member in a laminated glass.

[0041] That is, despite the inclusion of an ultraviolet absorber having a benzotriazole skeleton and a metal salt, the interlayer film according to the present invention is less susceptible to yellowing and can enhance the adhesive strength between the interlayer film and the laminated glass member.

[0042] Furthermore, when the interlayer film according to the present invention has a structure of two or more layers, it is also possible to increase the adhesive strength between the layers in the interlayer film.

[0043] The interlayer film preferably includes a layer containing an ultraviolet absorber (X) and a metal salt. When the interlayer film is a single-layer interlayer film having a single layer structure, the interlayer film includes only a first layer containing an ultraviolet absorber (X) and a metal salt. When the interlayer film is a multilayer interlayer film having a two or more layer structure, the interlayer film preferably includes at least one layer containing an ultraviolet absorber (X) and a metal salt. When the interlayer film is a multilayer interlayer film having a two or more layer structure, it is more preferable that at least one surface layer of the interlayer film is a layer containing an ultraviolet absorber (X) and a metal salt, and it is even more preferable that both surface layers of the interlayer film are layers containing an ultraviolet absorber (X) and a metal salt. When the interlayer film is a multilayer interlayer film having a two or more layer structure, it is more preferable that the second layer is a surface layer of the interlayer film, and that the second layer is a layer containing an ultraviolet absorber (X) and a metal salt. When the interlayer film is a multilayer interlayer film having a structure of three or more layers, it is more preferable that the third layer is a surface layer of the interlayer film and that the third layer is a layer containing the ultraviolet absorber (X) and a metal salt.When the interlayer film is a multilayer interlayer film having a structure of two or more layers, it is most preferable that all layers of the interlayer film are layers containing the ultraviolet absorber (X) and a metal salt.

[0044] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[0045] Fig. 1 is a cross-sectional view schematically showing an interlayer film for laminated glass according to a first embodiment of the present invention, in which a cross section of an interlayer film 11 in the thickness direction is shown.

[0046] The interlayer film 11 shown in FIG. 1 is a multilayer interlayer film having a structure of two or more layers. The interlayer film 11 is used to obtain laminated glass. The interlayer film 11 is an interlayer film for laminated glass. The interlayer film 11 includes a first layer 1, a second layer 2, and a third layer 3. The second layer 2 is disposed and laminated on a first surface 1a of the first layer 1. The third layer 3 is disposed and laminated on a second surface 1b of the first layer 1 opposite the first surface 1a. The first layer 1 is an interlayer. The second layer 2 and the third layer 3 are each protective layers, and in this embodiment, are surface layers. The first layer 1 is disposed and sandwiched between the second layer 2 and the third layer 3. Therefore, the interlayer film 11 has a multilayer structure (second layer 2 / first layer 1 / third layer 3) in which the second layer 2, first layer 1, and third layer 3 are laminated in this order.

[0047] The first layer 1 contains an ultraviolet absorber (X) and a metal salt. The second layer 2 contains an ultraviolet absorber (X) and a metal salt. The third layer 3 contains an ultraviolet absorber (X) and a metal salt. In the interlayer film 11, each layer provided in the interlayer film 11 contains an ultraviolet absorber (X) and a metal salt.

[0048] It should be noted that other layers may be disposed between the second layer 2 and the first layer 1, and between the first layer 1 and the third layer 3. Examples of other layers include layers containing polyethylene terephthalate, etc. It is preferable that the second layer 2 and the first layer 1, and the first layer 1 and the third layer 3 are directly laminated to each other.

[0049] 2 is a cross-sectional view schematically illustrating an interlayer film for laminated glass according to a second embodiment of the present invention, showing a cross section in the thickness direction of an interlayer film 11A.

[0050] The interlayer film 11A shown in FIG. 2 is a single-layer interlayer film having a one-layer structure. The interlayer film 11A is a first layer. The interlayer film 11A is used to obtain laminated glass. The interlayer film 11A is an interlayer film for laminated glass. The interlayer film 11A contains an ultraviolet absorber (X) and a metal salt.

[0051] Hereinafter, details of the first layer, the second layer, and the third layer that constitute the interlayer film according to the present invention, as well as details of each component contained in the first layer, the second layer, and the third layer, will be described.

[0052] <Ultraviolet absorber represented by formula (X) (ultraviolet absorber (X))> The interlayer film contains an ultraviolet absorber (X). The interlayer film includes a layer containing an ultraviolet absorber (X). The ultraviolet absorber (X) is an ultraviolet absorber represented by the following formula (X). The first layer preferably contains an ultraviolet absorber (X). The second layer preferably contains an ultraviolet absorber (X). The third layer preferably contains an ultraviolet absorber (X). Only one type of ultraviolet absorber (X) may be used, or two or more types may be used in combination. Furthermore, the ultraviolet absorber (X) contained in the first layer, the ultraviolet absorber (X) contained in the second layer, and the ultraviolet absorber (X) contained in the third layer may be the same or different.

[0053]

[0054] In the above formula (X), R １ represents any group, and R ２ ~R ８ represents a hydrogen atom, an atom other than a hydrogen atom, or an arbitrary group.

[0055] In the above formula (X), R １ is preferably a group having 1 or more carbon atoms, more preferably a group having 3 or more carbon atoms, and is preferably a group having 20 or less carbon atoms, and more preferably a group having 10 or less carbon atoms. In this case, the reactivity of the hydroxyl group directly bonded to the benzene ring in the ultraviolet absorber (X) with the metal salt can be further reduced, making it even more difficult for yellowing to occur.

[0056] In the above formula (X), R １ is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. １is more preferably a propyl group, a group represented by the following formula (R11), or a group represented by the following formula (R12): In this case, the reactivity of the hydroxyl group directly bonded to the benzene ring in the ultraviolet absorber (X) with the metal salt can be further reduced, making it even more difficult for yellowing to occur.

[0057]

[0058] In the above formula (R11), * represents the bonding position to the carbon atom that constitutes the benzene ring.

[0059]

[0060] In the above formula (R12), * represents the bonding position to the carbon atom that constitutes the benzene ring.

[0061] In the above formula (X), R ２ is preferably a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ２ is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ２ is preferably a hydrogen atom.

[0062] In the above formula (X), R ３ is preferably a group having 1 or more carbon atoms, more preferably a group having 3 or more carbon atoms, preferably a group having 30 or less carbon atoms, more preferably a group having 20 or less carbon atoms, and even more preferably a group having 10 or less carbon atoms. In this case, yellowing can be made even less likely to occur while maintaining high ultraviolet absorption performance.

[0063] In the above formula (X), R ３is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ３ is more preferably a propyl group, a group represented by the above formula (R11), or a group represented by the above formula (R12). In this case, the reactivity of the hydroxyl group directly bonded to the benzene ring in the ultraviolet absorber (X) with the metal salt can be further reduced, making it even more difficult for yellowing to occur.

[0064] In the above formula (X), R ４ is preferably a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ４ is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ４ is preferably a hydrogen atom.

[0065] In the above formula (X), R ５ is preferably a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ５is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ５ is preferably a hydrogen atom.

[0066] In the above formula (X), R ６ is preferably a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ６ is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ６ is preferably a hydrogen atom.

[0067] In the above formula (X), R ７ is preferably a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ７ is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ７is preferably a hydrogen atom.

[0068] In the above formula (X), R ８ is preferably a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ８ is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. ８ is preferably a hydrogen atom.

[0069] The ultraviolet absorber (X) preferably contains an ultraviolet absorber represented by the following formula (X1), and more preferably is an ultraviolet absorber represented by the following formula (X1). In this case, yellowing can be further reduced while maintaining high ultraviolet absorption performance.

[0070]

[0071] In the above formula (X1), R １ represents any group, and R ３ represents a group having one or more carbon atoms, and R ６ represents a hydrogen atom or a halogen atom.

[0072] In the above formula (X1), R １ is preferably a group having 1 or more carbon atoms, more preferably a group having 3 or more carbon atoms, and is preferably a group having 20 or less carbon atoms, and more preferably a group having 10 or less carbon atoms. In this case, the reactivity of the hydroxyl group directly bonded to the benzene ring in the ultraviolet absorber (X) with the metal salt can be further reduced, making it even more difficult for yellowing to occur.

[0073] In the above formula (X1), R １is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylamino group, an anilino group, an acylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, an alkylthio group, or an arylthio group. １ is more preferably a propyl group, a group represented by the above formula (R11), or a group represented by the above formula (R12). In this case, the reactivity of the hydroxyl group directly bonded to the benzene ring in the ultraviolet absorber (X) with the metal salt can be further reduced, making it even more difficult for yellowing to occur.

[0074] In the above formula (X1), R ３ is preferably a group having 1 or more carbon atoms, preferably a group having 30 or less carbon atoms, and more preferably a group having 10 or less carbon atoms. In this case, yellowing can be made even less likely to occur while maintaining high ultraviolet absorption performance.

[0075] In the above formula (X1), R ６ is preferably a hydrogen atom or a chlorine atom. In this case, yellowing can be made even less likely to occur while maintaining high ultraviolet absorbing performance.

[0076] The ultraviolet absorber (X) preferably contains an ultraviolet absorber represented by the following formula (X11), (X12), or (X13), and more preferably is an ultraviolet absorber represented by the following formula (X11), (X12), or (X13). In this case, yellowing can be made even less likely to occur while maintaining high ultraviolet absorption performance.

[0077]

[0078]

[0079]

[0080] The molecular weight of the ultraviolet absorber (X) is preferably 350 or more, more preferably 355 or more, even more preferably 380 or more, and preferably 600 or less, more preferably 500 or less. When the molecular weight of the ultraviolet absorber (X) is the above-mentioned lower limit or more and the above-mentioned upper limit or less, it is possible to further reduce yellowing while maintaining high ultraviolet absorption performance.

[0081] Commercially available ultraviolet absorbers (X) include "Tinuvin 234" and "Tinuvin 640" manufactured by BASF, "RIASORB UV-234" and "RIASORB UV-928" manufactured by Rianlon, "Eversorb 88" and "Eversorb 89" manufactured by Everlight Chemical, "Viosorb 234" manufactured by Kyodo Pharmaceutical, "SONGSORB 2340" and "SONGSORB 9280" manufactured by Songwon, "Eusorb UV-234" manufactured by Eutec, and "CHIGUARD 234" and "CHIGUARD 5228" manufactured by Chitec.

[0082] The content of the ultraviolet absorber (X) in 100 wt% of the layer (first layer, second layer, or third layer) containing the ultraviolet absorber (X) is preferably 0.1 wt% or more, more preferably 0.2 wt% or more, even more preferably 0.3 wt% or more, particularly preferably 0.4 wt% or more, and is preferably 7 wt% or less, more preferably 6 wt% or less, even more preferably 5 wt% or less, and particularly preferably 4 wt% or less. When the content of the ultraviolet absorber (X) is at least the above-mentioned lower limit, the ultraviolet transmittance Tuv of the interlayer film can be further reduced, and even when the interlayer film and laminated glass are used for a long period of time, the decrease in visible light transmittance can be further suppressed. In particular, when the content of the ultraviolet absorber (X) in 100 wt% of the layer containing the ultraviolet absorber (X) is 0.1 wt% or more, the decrease in visible light transmittance can be significantly suppressed even when the interlayer film and laminated glass are used for a long period of time. When the content of the ultraviolet absorber (X) is equal to or less than the upper limit, the dispersibility of the ultraviolet absorber (X) in the layer containing the ultraviolet absorber (X) can be further improved.

[0083] The content of the ultraviolet absorber (X) in 100% by weight of the interlayer film is preferably 0.1% by weight or more, more preferably 0.2% by weight or more, even more preferably 0.3% by weight or more, particularly preferably 0.4% by weight or more, and is preferably 7% by weight or less, more preferably 6% by weight or less, even more preferably 5% by weight or less, and particularly preferably 4% by weight or less. When the content of the ultraviolet absorber (X) is at least the above-mentioned lower limit, the ultraviolet transmittance Tuv of the interlayer film can be further reduced, and even when the interlayer film and laminated glass are used for a long period of time, the decrease in visible light transmittance can be further suppressed. In particular, when the content of the ultraviolet absorber (X) is 0.1% by weight or more in 100% by weight of the interlayer film, the decrease in visible light transmittance can be significantly suppressed even when the interlayer film and laminated glass are used for a long period of time. When the content of the ultraviolet absorber (X) is not more than the above-mentioned upper limit, the dispersibility of the ultraviolet absorber (X) in the interlayer film can be further improved.

[0084] The content of the ultraviolet absorber (X) in the layer containing the ultraviolet absorber (X) (first layer, second layer, or third layer) is preferably 0.1 part by weight or more, more preferably 0.2 part by weight or more, even more preferably 0.3 part by weight or more, and preferably 3 parts by weight or less, more preferably 2.5 parts by weight or less, and even more preferably 2 parts by weight or less, relative to 100 parts by weight of the thermoplastic resin in the layer containing the ultraviolet absorber (X) (first layer, second layer, or third layer). When the content of the ultraviolet absorber (X) is equal to or greater than the above-mentioned lower limit, the ultraviolet transmittance Tuv of the interlayer film can be further reduced, and even when the interlayer film and laminated glass are used for a long period of time, the decrease in visible light transmittance can be further suppressed. When the content of the ultraviolet absorber (X) is equal to or less than the above-mentioned upper limit, the dispersibility of the ultraviolet absorber (X) in the layer containing the ultraviolet absorber (X) can be further improved.

[0085] (Metal Salt) The interlayer film contains a metal salt. The interlayer film has a layer containing a metal salt. The first layer preferably contains the metal salt. The second layer preferably contains the metal salt. The third layer preferably contains the metal salt. The layer containing the ultraviolet absorber (X) preferably contains the metal salt. The use of the metal salt makes it easy to control the adhesion between the interlayer film and a laminated glass member such as a glass plate, or the adhesion between each layer in the interlayer film. Only one type of metal salt may be used, or two or more types may be used in combination. Furthermore, the metal salt contained in the first layer, the metal salt contained in the second layer, and the metal salt contained in the third layer may be the same or different.

[0086] The metal salt preferably includes an alkali metal salt or an alkaline earth metal salt, which makes it easier to control the adhesion between the interlayer film and the laminated glass member or the adhesion between the layers in the interlayer film.

[0087] The alkaline earth metals refer to six metals: Be, Mg, Ca, Sr, Ba, and Ra.

[0088] The metal salt preferably contains at least one metal selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba. The metal salt contained in the interlayer film preferably contains at least one metal selected from K and Mg, and more preferably contains Mg. When the metal salt contains Mg, collision safety can be improved even at a low water content.

[0089] The metal salt preferably contains a magnesium salt of an organic acid having a branched structure (P), which makes it easier to control the adhesion between the interlayer film and a laminated glass member such as a glass plate, or the adhesion between each layer in the interlayer film.

[0090] The magnesium salt of an organic acid having a branched structure (P) is preferably a magnesium salt of a carboxylic acid having a branched structure, which makes it easier to control the adhesion between the interlayer film and a laminated glass member such as a glass plate or the adhesion between layers in the interlayer film.

[0091] The metal salt preferably includes a metal salt (Q) of an organic acid having 2 to 8 carbon atoms, other than a magnesium salt of an organic acid having a branched structure. The metal salt (Q) of an organic acid having 2 to 8 carbon atoms is different from the magnesium salt (P) of an organic acid having a branched structure. This also makes it easier to control the adhesion between the interlayer film and a laminated glass member such as a glass plate, or the adhesion between each layer in the interlayer film.

[0092] The metal salt (Q) of an organic acid having from 2 to 8 carbon atoms is preferably a magnesium salt or a potassium salt of an organic acid having from 2 to 8 carbon atoms. In this case, it becomes even easier to control the adhesion between the interlayer film and a laminated glass member such as a glass plate, or the adhesion between the layers of the interlayer film.

[0093] The metal salt preferably contains the magnesium salt of the organic acid having a branched structure (P) and the metal salt of the organic acid having 2 or more and 8 or less carbon atoms (Q).

[0094] Furthermore, the metal salt may be an alkali metal salt of an organic acid having 2 to 16 carbon atoms, or an alkaline earth metal salt of an organic acid having 2 to 16 carbon atoms. The metal salt may include a magnesium salt of a carboxylic acid having 2 to 16 carbon atoms, or a potassium salt of a carboxylic acid having 2 to 16 carbon atoms.

[0095] Examples of the magnesium salts of carboxylic acids having 2 to 16 carbon atoms and the potassium salts of carboxylic acids having 2 to 16 carbon atoms include magnesium acetate, potassium acetate, magnesium propionate, potassium propionate, magnesium 2-ethylbutyrate, potassium 2-ethylbutanoate, magnesium 2-ethylhexanoate, and potassium 2-ethylhexanoate.

[0096] In a layer containing an ultraviolet absorber (X) and a metal salt, the weight ratio of the content of the metal contained in the metal salt to the content of the ultraviolet absorber (X) (content of metal contained in metal salt / content of ultraviolet absorber (X)) is preferably 0.1 or more, more preferably 1.5 or more, even more preferably 4 or more, particularly preferably 5 or more, and is preferably 50 or less, more preferably 35 or less. When the weight ratio (content of metal contained in metal salt / content of ultraviolet absorber (X)) is equal to or more than the above lower limit and equal to or less than the above upper limit, the effects of the present invention can be exhibited more effectively.

[0097] The total content of Mg and K in the interlayer film containing the metal salt or in a layer containing the metal salt (the first layer, the second layer, the third layer, or the layer containing the ultraviolet absorber (X)) is preferably 5 ppm or more, more preferably 10 ppm or more, even more preferably 20 ppm or more, and is preferably 300 ppm or less, more preferably 250 ppm or less, even more preferably 200 ppm or less. When the total content of Mg and K is at least the above-mentioned lower limit and at most the above-mentioned upper limit, the adhesion between the interlayer film and a laminated glass member (such as a glass plate) or the adhesion between the layers in the interlayer film can be more effectively controlled.

[0098] The Mg content in the interlayer film containing the metal salt or the layer containing the metal salt (the first layer, the second layer, the third layer, or the layer containing the ultraviolet absorber (X)) is preferably 5 ppm or more, more preferably 10 ppm or more, and even more preferably 20 ppm or more, and is preferably 300 ppm or less, more preferably 250 ppm or less, and even more preferably 200 ppm or less.

[0099] The Mg and K contents and the Mg content can be determined from the blending amounts of metal salts contained in each layer, or by measurement using an ICP emission spectrometer.

[0100] (Thermoplastic Resin) The interlayer film preferably contains a thermoplastic resin (hereinafter may be referred to as thermoplastic resin (0)). The interlayer film preferably contains a polyvinyl acetal resin (hereinafter may be referred to as polyvinyl acetal resin (0)) as the thermoplastic resin (0). The first layer preferably contains a thermoplastic resin (hereinafter may be referred to as thermoplastic resin (1)). The first layer preferably contains a polyvinyl acetal resin (hereinafter may be referred to as polyvinyl acetal resin (1)) as the thermoplastic resin (1). The second layer preferably contains a thermoplastic resin (hereinafter may be referred to as thermoplastic resin (2)). The second layer preferably contains a polyvinyl acetal resin (hereinafter may be referred to as polyvinyl acetal resin (2)) as the thermoplastic resin (2). The third layer preferably contains a thermoplastic resin (hereinafter may be referred to as thermoplastic resin (3)). The third layer preferably contains a polyvinyl acetal resin (hereinafter, sometimes referred to as polyvinyl acetal resin (3)) as the thermoplastic resin (3). The layer containing the ultraviolet absorber (X) preferably contains a thermoplastic resin (hereinafter, sometimes referred to as thermoplastic resin (4)). The layer containing the ultraviolet absorber (X) preferably contains a polyvinyl acetal resin (hereinafter, sometimes referred to as polyvinyl acetal resin (4)) as the thermoplastic resin (4). The thermoplastic resin (1), the thermoplastic resin (2), the thermoplastic resin (3), and the thermoplastic resin (4) may be the same or different. Since sound insulation is further improved, the thermoplastic resin (1) is preferably different from the thermoplastic resin (2) and the thermoplastic resin (3). The polyvinyl acetal resin (1), the polyvinyl acetal resin (2), the polyvinyl acetal resin (3), and the polyvinyl acetal resin (4) may be the same or different. The polyvinyl acetal resin (1) is preferably different from the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3), since this further improves the sound insulation.The thermoplastic resin (0), the thermoplastic resin (1), the thermoplastic resin (2), the thermoplastic resin (3), and the thermoplastic resin (4) may each be used alone or in combination of two or more thereof. The polyvinyl acetal resin (0), the polyvinyl acetal resin (1), the polyvinyl acetal resin (2), the polyvinyl acetal resin (3), and the polyvinyl acetal resin (4) may each be used alone or in combination of two or more thereof.

[0101] Examples of the thermoplastic resin include polyvinyl acetal resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, polyurethane resin, (meth)acrylic resin, polyolefin resin, ionomer resin, polyvinyl alcohol resin, etc. Thermoplastic resins other than these may also be used.

[0102] The polyvinyl acetal resin can be produced, for example, by acetalizing polyvinyl alcohol (PVA) with an aldehyde. The polyvinyl acetal resin is preferably an acetalized product of polyvinyl alcohol. The polyvinyl alcohol can be obtained, for example, by saponifying polyvinyl acetate. The degree of saponification of the polyvinyl alcohol is generally within the range of 70 mol% to 99.9 mol%.

[0103] The average degree of polymerization of the polyvinyl alcohol (PVA) is preferably 200 or more, more preferably 500 or more, even more preferably 1500 or more, even more preferably 1600 or more, particularly preferably 2600 or more, and most preferably 2700 or more, and is preferably 5000 or less, more preferably 4000 or less, and even more preferably 3500 or less. When the average degree of polymerization is at least the lower limit, the penetration resistance of the laminated glass is further improved. When the average degree of polymerization is at most the upper limit, the interlayer film is easily formed.

[0104] The average degree of polymerization of the polyvinyl alcohol is determined by a method in accordance with JIS K6726 "Testing methods for polyvinyl alcohol."

[0105] The number of carbon atoms in the acetal group contained in the polyvinyl acetal resin is not particularly limited. The aldehyde used in producing the polyvinyl acetal resin is not particularly limited. The number of carbon atoms in the acetal group in the polyvinyl acetal resin is preferably 3 to 5, and more preferably 3 or 4. When the number of carbon atoms in the acetal group in the polyvinyl acetal resin is 3 or more, the glass transition temperature of the interlayer film is sufficiently low. The number of carbon atoms in the acetal group in the polyvinyl acetal resin may be 4 or 5.

[0106] The aldehyde is not particularly limited. In general, an aldehyde having 1 to 10 carbon atoms is suitably used. Examples of the aldehyde having 1 to 10 carbon atoms include propionaldehyde, n-butyraldehyde, isobutyraldehyde, n-valeraldehyde, 2-ethylbutyraldehyde, n-hexylaldehyde, n-octylaldehyde, n-nonylaldehyde, n-decylaldehyde, formaldehyde, acetaldehyde, and benzaldehyde. The aldehyde is preferably propionaldehyde, n-butyraldehyde, isobutyraldehyde, n-hexylaldehyde, or n-valeraldehyde, more preferably propionaldehyde, n-butyraldehyde, or isobutyraldehyde, and even more preferably n-butyraldehyde. The above aldehydes may be used alone or in combination of two or more.

[0107] The hydroxyl group content (hydroxyl group amount) of the polyvinyl acetal resin (0) is preferably 15 mol% or more, more preferably 18 mol% or more, and preferably 40 mol% or less, more preferably 35 mol% or less. When the hydroxyl group content is equal to or greater than the lower limit, the adhesive strength of the interlayer film is further increased. When the hydroxyl group content is equal to or less than the upper limit, the flexibility of the interlayer film is increased, making it easier to handle.

[0108] The hydroxyl group content (hydroxyl group amount) of the polyvinyl acetal resin (1) is preferably 17 mol% or more, more preferably 20 mol% or more, even more preferably 22 mol% or more, and preferably 28 mol% or less, more preferably 27 mol% or less, even more preferably 25 mol% or less, and particularly preferably 24 mol% or less. When the hydroxyl group content is equal to or greater than the lower limit, the mechanical strength of the interlayer film is further increased. In particular, when the hydroxyl group content of the polyvinyl acetal resin (1) is 20 mol% or more, the reaction efficiency is high and productivity is excellent, and when it is 28 mol% or less, the sound insulation of the laminated glass is further improved. Furthermore, when the hydroxyl group content is equal to or less than the upper limit, the flexibility of the interlayer film is high, making it easier to handle.

[0109] When the layer containing the ultraviolet absorber (X) is not a surface layer of the interlayer film, the preferred range of the hydroxyl group content of the polyvinyl acetal resin (4) is the same as the preferred range of the hydroxyl group content of the polyvinyl acetal resin (1).

[0110] The hydroxyl group content (hydroxyl group amount) of the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3) is preferably 25 mol% or more, more preferably 28 mol% or more, more preferably 30 mol% or more, even more preferably 31.5 mol% or more, even more preferably 32 mol% or more, and particularly preferably 33 mol% or more. The hydroxyl group content (hydroxyl group amount) of the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3) is preferably 38 mol% or less, more preferably 37 mol% or less, even more preferably 36.5 mol% or less, and particularly preferably 36 mol% or less. When the hydroxyl group content is at least the lower limit, the adhesive strength of the interlayer film is further increased. On the other hand, when the hydroxyl group content is at most the upper limit, the flexibility of the interlayer film is increased, making the interlayer film easier to handle.

[0111] When the layer containing the ultraviolet absorber (X) is the surface layer of the interlayer film, the preferred range of the hydroxyl group content of the polyvinyl acetal resin (4) is the same as the preferred range of the hydroxyl group content of the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3).

[0112] From the viewpoint of further improving sound insulation, the hydroxyl group content of the polyvinyl acetal resin (1) is preferably lower than the hydroxyl group content of the polyvinyl acetal resin (2). From the viewpoint of further improving sound insulation, the hydroxyl group content of the polyvinyl acetal resin (1) is preferably lower than the hydroxyl group content of the polyvinyl acetal resin (3). The absolute value of the difference between the hydroxyl group content of the polyvinyl acetal resin (1) and the hydroxyl group content of the polyvinyl acetal resin (2) is defined as absolute value A, and the absolute value of the difference between the hydroxyl group content of the polyvinyl acetal resin (1) and the hydroxyl group content of the polyvinyl acetal resin (3) is defined as absolute value B. From the viewpoint of further improving sound insulation, the absolute values ​​A and B are each preferably 1 mol% or more, more preferably 5 mol% or more, even more preferably 9 mol% or more, particularly preferably 10 mol% or more, and most preferably 12 mol% or more. The absolute value A and the absolute value B are each preferably 20 mol % or less.

[0113] When the layer containing the ultraviolet absorber (X) is not a surface layer of an interlayer film, from the viewpoint of further enhancing sound insulation, the hydroxyl group content of the polyvinyl acetal resin (4) is preferably lower than the hydroxyl group content of the polyvinyl acetal resin (2). When the layer containing the ultraviolet absorber (X) is not a surface layer of an interlayer film, from the viewpoint of further enhancing sound insulation, the hydroxyl group content of the polyvinyl acetal resin (4) is preferably lower than the hydroxyl group content of the polyvinyl acetal resin (3). The absolute value of the difference between the hydroxyl group content of the polyvinyl acetal resin (4) and the hydroxyl group content of the polyvinyl acetal resin (2) is defined as absolute value C, and the absolute value of the difference between the hydroxyl group content of the polyvinyl acetal resin (4) and the hydroxyl group content of the polyvinyl acetal resin (3) is defined as absolute value D. From the viewpoint of further improving sound insulation, the absolute value C and the absolute value D are each preferably 1 mol % or more, more preferably 5 mol % or more, even more preferably 9 mol % or more, particularly preferably 10 mol % or more, and most preferably 12 mol % or more. The absolute value C and the absolute value D are each preferably 20 mol % or less.

[0114] When the layer containing the ultraviolet absorber (X) is the surface layer of an interlayer film, from the viewpoint of further improving sound insulation, the hydroxyl group content of the polyvinyl acetal resin (1) is preferably lower than the hydroxyl group content of the polyvinyl acetal resin (4). When the layer containing the ultraviolet absorber (X) is the surface layer of an interlayer film, from the viewpoint of further improving sound insulation, the absolute value of the difference between the hydroxyl group content of the polyvinyl acetal resin (1) and the hydroxyl group content of the polyvinyl acetal resin (4) is preferably 1 mol% or more, more preferably 5 mol% or more, even more preferably 9 mol% or more, particularly preferably 10 mol% or more, and most preferably 12 mol% or more. The absolute value of the difference between the hydroxyl group content of the polyvinyl acetal resin (1) and the hydroxyl group content of the polyvinyl acetal resin (4) is preferably 20 mol% or less.

[0115] The hydroxyl group content of the polyvinyl acetal resin is a molar fraction calculated by dividing the amount of ethylene groups having hydroxyl groups by the total amount of ethylene groups in the main chain, and is expressed as a percentage. The amount of ethylene groups having hydroxyl groups can be measured, for example, in accordance with JIS K6728 "Testing Methods for Polyvinyl Butyral."

[0116] The degree of acetylation (amount of acetyl groups) of the polyvinyl acetal resin (0) is preferably 0.1 mol% or more, more preferably 0.3 mol% or more, even more preferably 0.5 mol% or more, and is preferably 30 mol% or less, more preferably 25 mol% or less, even more preferably 20 mol% or less. When the degree of acetylation is equal to or greater than the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer is improved. When the degree of acetylation is equal to or less than the upper limit, the moisture resistance of the interlayer film and laminated glass is improved.

[0117] The degree of acetylation (amount of acetyl groups) of the polyvinyl acetal resin (1) is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, even more preferably 7 mol% or more, even more preferably 9 mol% or more, preferably 30 mol% or less, more preferably 25 mol% or less, even more preferably 24 mol% or less, and particularly preferably 20 mol% or less. When the degree of acetylation is at least the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer is improved. When the degree of acetylation is at most the upper limit, the moisture resistance of the interlayer film and laminated glass is improved. In particular, when the degree of acetylation of the polyvinyl acetal resin (1) is 0.1 mol% or more and 25 mol% or less, excellent penetration resistance is achieved.

[0118] When the layer containing the ultraviolet absorber (X) is not a surface layer of the interlayer film, the preferred range of the acetylation degree of the polyvinyl acetal resin (4) is the same as the preferred range of the acetylation degree of the polyvinyl acetal resin (1).

[0119] The acetylation degree (acetyl group amount) of each of the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3) is preferably 0.01 mol% or more, more preferably 0.5 mol% or more, and preferably 10 mol% or less, more preferably 2 mol% or less. When the acetylation degree is equal to or greater than the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer is improved. When the acetylation degree is equal to or less than the upper limit, the moisture resistance of the interlayer film and the laminated glass is improved.

[0120] When the layer containing the ultraviolet absorber (X) is the surface layer of the interlayer film, the preferred range of the acetylation degree of the polyvinyl acetal resin (4) is the same as the preferred range of the acetylation degree of the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3).

[0121] The degree of acetylation is a molar fraction calculated by dividing the amount of ethylene groups having acetyl groups by the total amount of ethylene groups in the main chain, and is expressed as a percentage. The amount of ethylene groups having acetyl groups can be measured, for example, in accordance with JIS K6728 "Testing Methods for Polyvinyl Butyral."

[0122] The degree of acetalization of the polyvinyl acetal resin (0) (the degree of butyralization in the case of a polyvinyl butyral resin) is preferably 60 mol% or more, more preferably 63 mol% or more, and preferably 85 mol% or less, more preferably 75 mol% or less, and even more preferably 70 mol% or less. When the degree of acetalization is equal to or greater than the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer is increased. When the degree of acetalization is equal to or less than the upper limit, the reaction time required to produce the polyvinyl acetal resin is shortened.

[0123] The degree of acetalization of the polyvinyl acetal resin (1) (the degree of butyralization in the case of a polyvinyl butyral resin) is preferably 47 mol% or more, more preferably 60 mol% or more, and preferably 85 mol% or less, more preferably 80 mol% or less, and even more preferably 75 mol% or less. When the degree of acetalization is equal to or greater than the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer is increased. When the degree of acetalization is equal to or less than the upper limit, the reaction time required to produce the polyvinyl acetal resin is shortened.

[0124] When the layer containing the ultraviolet absorber (X) is not a surface layer of the interlayer film, the preferred range of the degree of acetalization of the polyvinyl acetal resin (4) is the same as the preferred range of the degree of acetalization of the polyvinyl acetal resin (1).

[0125] The degree of acetalization of the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3) (the degree of butyralization in the case of a polyvinyl butyral resin) is preferably 55 mol% or more, more preferably 60 mol% or more, and preferably 75 mol% or less, more preferably 71 mol% or less. When the degree of acetalization is equal to or greater than the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer is increased. When the degree of acetalization is equal to or less than the upper limit, the reaction time required to produce the polyvinyl acetal resin is shortened.

[0126] When the layer containing the ultraviolet absorber (X) is the surface layer of the interlayer film, the preferred range of the degree of acetalization of the polyvinyl acetal resin (4) is the same as the preferred range of the degree of acetalization of the polyvinyl acetal resin (2) and the polyvinyl acetal resin (3).

[0127] The degree of acetalization is determined as follows. First, the amount of ethylene groups to which hydroxyl groups are bonded and the amount of ethylene groups to which acetyl groups are bonded are subtracted from the total amount of ethylene groups in the main chain to determine the value. The obtained value is divided by the total amount of ethylene groups in the main chain to determine the molar fraction. The value expressed as a percentage of this molar fraction is the degree of acetalization.

[0128] The hydroxyl group content (hydroxyl group amount), acetalization degree (butyralization degree), and acetylation degree are preferably calculated from the results of measurements made in accordance with JIS K6728 "Testing Methods for Polyvinyl Butyral." However, measurements made in accordance with ASTM D1396-92 may also be used. When the polyvinyl acetal resin is a polyvinyl butyral resin, the hydroxyl group content (hydroxyl group amount), acetalization degree (butyralization degree), and acetylation degree can be calculated from the results of measurements made in accordance with JIS K6728 "Testing Methods for Polyvinyl Butyral."

[0129] The content of polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the interlayer film is preferably 10% by weight or more, more preferably 30% by weight or more, even more preferably 50% by weight or more, even more preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more. The content of polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the interlayer film is preferably 100% by weight or less. The main component (50% by weight or more) of the thermoplastic resin of the interlayer film is preferably polyvinyl acetal resin.

[0130] The content of the polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the first layer is preferably 10% by weight or more, more preferably 30% by weight or more, even more preferably 50% by weight or more, even more preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more. The content of the polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the first layer is preferably 100% by weight or less. The main component (50% by weight or more) of the thermoplastic resin in the first layer is preferably polyvinyl acetal resin.

[0131] The content of the polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the second layer is preferably 10% by weight or more, more preferably 30% by weight or more, even more preferably 50% by weight or more, even more preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more. The content of the polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the second layer is preferably 100% by weight or less. The main component (50% by weight or more) of the thermoplastic resin in the second layer is preferably polyvinyl acetal resin.

[0132] The content of the polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the third layer is preferably 10% by weight or more, more preferably 30% by weight or more, even more preferably 50% by weight or more, even more preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more. The content of the polyvinyl acetal resin in 100% by weight of the thermoplastic resin contained in the third layer is preferably 100% by weight or less. The main component (50% by weight or more) of the thermoplastic resin in the third layer is preferably polyvinyl acetal resin.

[0133] The content of polyvinyl acetal resin in 100% by weight of thermoplastic resin contained in the layer containing the ultraviolet absorber (X) is preferably 10% by weight or more, more preferably 30% by weight or more, even more preferably 50% by weight or more, even more preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more. The content of polyvinyl acetal resin in 100% by weight of thermoplastic resin contained in the layer containing the ultraviolet absorber (X) is preferably 100% by weight or less. The main component (50% by weight or more) of the thermoplastic resin in the layer containing the ultraviolet absorber (X) is preferably polyvinyl acetal resin.

[0134] (Plasticizer) From the viewpoint of further increasing the adhesive strength of the interlayer film, the interlayer film according to the present invention preferably contains a plasticizer (hereinafter, sometimes referred to as plasticizer (0)). The first layer preferably contains a plasticizer (hereinafter, sometimes referred to as plasticizer (1)). The second layer preferably contains a plasticizer (hereinafter, sometimes referred to as plasticizer (2)). The third layer preferably contains a plasticizer (hereinafter, sometimes referred to as plasticizer (3)). The layer containing the ultraviolet absorber (X) preferably contains a plasticizer (hereinafter, sometimes referred to as plasticizer (4)). When the thermoplastic resin contained in the interlayer film is a polyvinyl acetal resin, it is particularly preferable that the interlayer film (each layer) contains a plasticizer. The layer containing a polyvinyl acetal resin preferably contains a plasticizer.

[0135] The plasticizer is not particularly limited. Any conventionally known plasticizer can be used as the plasticizer. Only one type of plasticizer may be used, or two or more types may be used in combination.

[0136] Examples of the plasticizer include organic ester plasticizers such as monobasic organic acid esters and polybasic organic acid esters, organic phosphate plasticizers, and organic phosphite plasticizers. The plasticizer is preferably an organic ester plasticizer. The plasticizer is preferably a liquid plasticizer.

[0137] Examples of the monobasic organic acid ester include glycol esters obtained by reacting glycol with a monobasic organic acid. Examples of the glycol include triethylene glycol, tetraethylene glycol, and tripropylene glycol. Examples of the monobasic organic acid include butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptyl acid, n-octylic acid, 2-ethylhexyl acid, n-nonylic acid, decylic acid, and benzoic acid.

[0138] Examples of the polybasic organic acid ester include ester compounds of a polybasic organic acid and an alcohol having a linear or branched structure and having 4 to 8 carbon atoms. Examples of the polybasic organic acid include adipic acid, sebacic acid, and azelaic acid.

[0139] Examples of the organic ester plasticizer include triethylene glycol di-2-ethylpropanoate, triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethylene glycol di-n-octanoate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, dibutyl sebacate, dioctyl azelate, dibutyl carbitol adipate, ethylene glycol di-2-ethylbutyrate, 1,3-propylene glycol di-2-ethylbutyrate, 1,4-butylene glycol di-2-ethylbutyrate, and diethylene glycol di-2-ethylbutylene. Examples of suitable organic ester plasticizers include diethylene glycol di-2-ethylhexanoate, dipropylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylpentanoate, tetraethylene glycol di-2-ethylbutyrate, diethylene glycol dicaprylate, diethylene glycol dibenzoate, dipropylene glycol dibenzoate, dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, a mixture of heptyl adipate and nonyl adipate, diisononyl adipate, diisodecyl adipate, heptylnonyl adipate, dibutyl sebacate, oil-modified alkyd sebacate, and a mixture of a phosphate ester and an adipate. Organic ester plasticizers other than those listed above may also be used as the organic ester plasticizer. Furthermore, adipate esters other than the above-mentioned adipate esters may also be used as the adipate ester.

[0140] Examples of the organic phosphoric acid plasticizer include tributoxyethyl phosphate, isodecylphenyl phosphate, and triisopropyl phosphate.

[0141] The plasticizer is preferably a diester plasticizer represented by the following formula (1):

[0142]

[0143] In the above formula (1), R1 and R2 each represent an organic group having 2 to 10 carbon atoms, R3 represents an ethylene group, an isopropylene group, or an n-propylene group, and p represents an integer of 3 to 10. In the above formula (1), R1 and R2 each preferably represent an organic group having 5 to 10 carbon atoms, and more preferably represent an organic group having 6 to 10 carbon atoms.

[0144] The plasticizer preferably includes triethylene glycol di-2-ethylhexanoate (3GO), triethylene glycol di-2-ethylbutyrate (3GH), or triethylene glycol di-2-ethylpropanoate. The plasticizer more preferably includes triethylene glycol di-2-ethylhexanoate (3GO) or triethylene glycol di-2-ethylbutyrate (3GH), and even more preferably includes triethylene glycol di-2-ethylhexanoate (3GO).

[0145] The content of the plasticizer (0) in the interlayer film relative to 100 parts by weight of the thermoplastic resin (0) is defined as the content (0). The content (0) is preferably 5 parts by weight or more, more preferably 25 parts by weight or more, even more preferably 30 parts by weight or more, and preferably 100 parts by weight or less, more preferably 60 parts by weight or less, even more preferably 50 parts by weight or less. When the content (0) is at least the lower limit, the penetration resistance of the laminated glass is further improved. When the content (0) is at most the upper limit, the transparency of the interlayer film is further improved.

[0146] In the first layer, the content of the plasticizer (1) relative to 100 parts by weight of the thermoplastic resin (1) is defined as content (1). The content (1) is preferably 50 parts by weight or more, more preferably 55 parts by weight or more, and even more preferably 60 parts by weight or more. The content (1) is preferably 100 parts by weight or less, more preferably 90 parts by weight or less, even more preferably 85 parts by weight or less, and particularly preferably 80 parts by weight or less. When the content (1) is equal to or greater than the lower limit, the flexibility of the interlayer film is increased, making the interlayer film easier to handle. When the content (1) is equal to or less than the upper limit, the penetration resistance of the laminated glass is further improved.

[0147] When the layer containing the ultraviolet absorber (X) is not a surface layer of an interlayer film, the preferred range of the content of the plasticizer (4) relative to 100 parts by weight of the thermoplastic resin (4) in the layer containing the ultraviolet absorber (X) (hereinafter, may be referred to as content (4)) is the same as the preferred range of content (1).

[0148] In the second layer, the content of the plasticizer (2) relative to 100 parts by weight of the thermoplastic resin (2) is defined as content (2). In the third layer, the content of the plasticizer (3) relative to 100 parts by weight of the thermoplastic resin (3) is defined as content (3). The contents (2) and (3) are each preferably 5 parts by weight or more, more preferably 10 parts by weight or more, even more preferably 15 parts by weight or more, even more preferably 20 parts by weight or more, particularly preferably 24 parts by weight or more, and most preferably 25 parts by weight or more. The contents (2) and (3) are each preferably 45 parts by weight or less, more preferably 40 parts by weight or less, even more preferably 35 parts by weight or less, particularly preferably 32 parts by weight or less, and most preferably 30 parts by weight or less. When the contents (2) and (3) are equal to or greater than the lower limits, the flexibility of the interlayer film is increased, making the interlayer film easier to handle. When the content (2) and the content (3) are equal to or less than the upper limit, the penetration resistance of the laminated glass is further improved.

[0149] When the layer containing the ultraviolet absorber (X) is a surface layer of an interlayer film, the preferred range of the content of the plasticizer (4) relative to 100 parts by weight of the thermoplastic resin (4) in the layer containing the ultraviolet absorber (X) (hereinafter, may be referred to as content (4)) is the same as the preferred ranges of the content (2) and the content (3).

[0150] In order to improve the sound insulation of the laminated glass, the content (1) is preferably greater than the content (2), and the content (1) is preferably greater than the content (3).

[0151] When the layer containing the ultraviolet absorber (X) is not a surface layer of the interlayer film, the content (4) is preferably greater than the content (2), and the content (4) is preferably greater than the content (3), in order to enhance the sound insulation of the laminated glass.

[0152] When the layer containing the ultraviolet absorber (X) is the surface layer of the interlayer film, the content (1) is preferably greater than the content (4) in order to improve the sound insulation of the laminated glass.

[0153] From the viewpoint of further improving the sound insulation of the laminated glass, the absolute value of the difference between the content (2) and the content (1) and the absolute value of the difference between the content (3) and the content (1) are each preferably 10 parts by weight or more, more preferably 15 parts by weight or more, and even more preferably 20 parts by weight or more. The absolute value of the difference between the content (2) and the content (1) and the absolute value of the difference between the content (3) and the content (1) are each preferably 80 parts by weight or less, more preferably 75 parts by weight or less, and even more preferably 70 parts by weight or less.

[0154] When the layer containing the ultraviolet absorber (X) is not a surface layer of the interlayer film, from the viewpoint of further improving the sound insulation of the laminated glass, the absolute value of the difference between the content (2) and the content (4) and the absolute value of the difference between the content (3) and the content (4) are each preferably 10 parts by weight or more, more preferably 15 parts by weight or more, and even more preferably 20 parts by weight or more. The absolute value of the difference between the content (2) and the content (4) and the absolute value of the difference between the content (3) and the content (4) are each preferably 80 parts by weight or less, more preferably 75 parts by weight or less, and even more preferably 70 parts by weight or less.

[0155] When the layer containing the ultraviolet absorber (X) is the surface layer of the interlayer film, from the viewpoint of further improving the sound insulation of the laminated glass, the absolute value of the difference between the content (4) and the content (1) is preferably 10 parts by weight or more, more preferably 15 parts by weight or more, and even more preferably 20 parts by weight or more. The absolute value of the difference between the content (4) and the content (1) is preferably 80 parts by weight or less, more preferably 75 parts by weight or less, and even more preferably 70 parts by weight or less.

[0156] (Heat-shielding substance) The interlayer film preferably contains a heat-shielding substance. The first layer preferably contains a heat-shielding substance. The second layer preferably contains a heat-shielding substance. The third layer preferably contains a heat-shielding substance. The layer containing the ultraviolet absorber (X) preferably contains a heat-shielding substance. Only one type of heat-shielding substance may be used, or two or more types may be used in combination.

[0157] The heat-shielding material preferably contains at least one component X selected from a phthalocyanine compound, a naphthalocyanine compound, and an anthracyanine compound, or contains heat-shielding particles. In this case, the heat-shielding material may contain both the component X and the heat-shielding particles.

[0158] Component X: The interlayer film preferably contains at least one component X selected from a phthalocyanine compound, a naphthalocyanine compound, and an anthracyanine compound. The first layer preferably contains the component X. The second layer preferably contains the component X. The third layer preferably contains the component X. The layer containing the ultraviolet absorber (X) preferably contains the component X. The component X is a heat-shielding substance. Only one type of component X may be used, or two or more types may be used in combination.

[0159] There are no particular restrictions on the component X. As the component X, conventionally known phthalocyanine compounds, naphthalocyanine compounds, and anthracyanine compounds can be used.

[0160] Examples of the component X include phthalocyanine, phthalocyanine derivatives, naphthalocyanine, naphthalocyanine derivatives, anthracyanine, and anthracyanine derivatives. The phthalocyanine compound and the phthalocyanine derivative preferably have a phthalocyanine skeleton. The naphthalocyanine compound and the naphthalocyanine derivative preferably have a naphthalocyanine skeleton. The anthracyanine compound and the anthracyanine derivative preferably have an anthracyanine skeleton.

[0161] From the viewpoint of further improving the heat-shielding properties of the interlayer film and laminated glass, the component X is preferably at least one selected from the group consisting of phthalocyanine, phthalocyanine derivatives, naphthalocyanine, and naphthalocyanine derivatives, and more preferably at least one of phthalocyanine and phthalocyanine derivatives.

[0162] From the viewpoint of effectively improving the heat-shielding properties and maintaining a higher visible light transmittance for a long period of time, the component X preferably contains a vanadium atom or a copper atom. The component X preferably contains a vanadium atom, and also preferably contains a copper atom. The component X is more preferably at least one of a phthalocyanine containing a vanadium atom or a copper atom and a derivative of a phthalocyanine containing a vanadium atom or a copper atom. From the viewpoint of further improving the heat-shielding properties of the interlayer film and laminated glass, the component X preferably has a structural unit in which an oxygen atom is bonded to a vanadium atom.

[0163] The content of component X in 100 wt % of the interlayer film or in 100 wt % of the layer containing component X (the first layer, the second layer, the third layer, or the layer containing ultraviolet absorber (X)) is preferably 0.001 wt % or more, more preferably 0.005 wt % or more, even more preferably 0.01 wt % or more, and particularly preferably 0.02 wt % or more. The content of component X in 100 wt % of the interlayer film or in 100 wt % of the layer containing component X (the first layer, the second layer, the third layer, or the layer containing ultraviolet absorber (X)) is preferably 0.2 wt % or less, more preferably 0.1 wt % or less, even more preferably 0.05 wt % or less, and particularly preferably 0.04 wt % or less. When the content of component X is equal to or greater than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, the heat-shielding properties and the visible light transmittance are sufficiently high. For example, a visible light transmittance of 70% or more is possible.

[0164] Heat-shielding particles: The interlayer film preferably contains heat-shielding particles. The first layer preferably contains heat-shielding particles. The second layer preferably contains heat-shielding particles. The third layer preferably contains heat-shielding particles. The layer containing the ultraviolet absorber (X) preferably contains heat-shielding particles. The heat-shielding particles are a heat-shielding substance. The use of heat-shielding particles can effectively block infrared rays (heat rays). Only one type of heat-shielding particle may be used, or two or more types may be used in combination.

[0165] From the viewpoint of further enhancing the heat-shielding properties of the laminated glass, the heat-shielding particles are more preferably metal oxide particles, and the heat-shielding particles are preferably particles formed from a metal oxide (metal oxide particles).

[0166] Infrared rays, which have wavelengths of 780 nm or more, which are longer than visible light, have a smaller amount of energy than ultraviolet rays. However, infrared rays have a large thermal effect, and when infrared rays are absorbed by a substance, they are released as heat. For this reason, infrared rays are generally called heat rays. By using the above heat-shielding particles, infrared rays (heat rays) can be effectively blocked. Here, heat-shielding particles refer to particles that can absorb infrared rays.

[0167] Specific examples of the heat-shielding particles include metal oxide particles such as aluminum-doped tin oxide particles, indium-doped tin oxide particles, antimony-doped tin oxide particles (ATO particles), gallium-doped zinc oxide particles (GZO particles), indium-doped zinc oxide particles (IZO particles), aluminum-doped zinc oxide particles (AZO particles), niobium-doped titanium oxide particles, sodium-doped tungsten oxide particles, cesium-doped tungsten oxide particles, thallium-doped tungsten oxide particles, rubidium-doped tungsten oxide particles, tin-doped indium oxide particles (ITO particles), tin-doped zinc oxide particles, and silicon-doped zinc oxide particles; ６) particles, etc. Heat-shielding particles other than these may also be used. Metal oxide particles are preferred because of their high heat-ray shielding function, and ATO particles, GZO particles, IZO particles, ITO particles, or tungsten oxide particles are more preferred, with ITO particles or tungsten oxide particles being particularly preferred. In particular, tin-doped indium oxide particles (ITO particles) are preferred because of their high heat-ray shielding function and ease of availability, and tungsten oxide particles are also preferred.

[0168] From the viewpoint of further improving the heat-shielding properties of the interlayer film and laminated glass, the tungsten oxide particles are preferably metal-doped tungsten oxide particles. The "tungsten oxide particles" include metal-doped tungsten oxide particles. Specific examples of the metal-doped tungsten oxide particles include sodium-doped tungsten oxide particles, cesium-doped tungsten oxide particles, thallium-doped tungsten oxide particles, and rubidium-doped tungsten oxide particles.

[0169] From the viewpoint of further improving the heat-shielding properties of the interlayer film and laminated glass, cesium-doped tungsten oxide particles are particularly preferred. From the viewpoint of further improving the heat-shielding properties of the interlayer film and laminated glass, the cesium-doped tungsten oxide particles are represented by the formula: Cs ０．３３ WO ３ Preferably, the tungsten oxide particles are represented by the formula:

[0170] The average particle size of the heat-shielding particles is preferably 0.01 μm or more, more preferably 0.02 μm or more, and preferably 0.1 μm or less, more preferably 0.05 μm or less. When the average particle size is equal to or greater than the lower limit, the heat ray shielding property is sufficiently high. When the average particle size is equal to or less than the upper limit, the dispersibility of the heat-shielding particles is high.

[0171] The "average particle size" refers to the volume average particle size. The average particle size can be measured using a particle size distribution analyzer ("UPA-EX150" manufactured by Nikkiso Co., Ltd.) or the like.

[0172] The content of the heat-shielding particles (particularly the content of tungsten oxide particles) in 100 weight % of the interlayer film or 100 weight % of the layer containing the heat-shielding particles (the first layer, the second layer, the third layer, or the layer containing the ultraviolet absorber (X)) is preferably 0.01 weight % or more, more preferably 0.1 weight % or more, even more preferably 1 weight % or more, and particularly preferably 1.5 weight % or more. The content of the heat-shielding particles (particularly the content of tungsten oxide particles) in 100 weight % of the interlayer film or 100 weight % of the layer containing the heat-shielding particles (the first layer, the second layer, the third layer, or the layer containing the ultraviolet absorber (X)) is preferably 6 weight % or less, more preferably 5.5 weight % or less, even more preferably 4 weight % or less, particularly preferably 3.5 weight % or less, and most preferably 3 weight % or less. When the content of the heat-shielding particles is at least the above-mentioned lower limit and at most the above-mentioned upper limit, the heat-shielding property is sufficiently high and the visible light transmittance is sufficiently high.

[0173] (Antioxidant) The interlayer film preferably contains an antioxidant. The first layer preferably contains an antioxidant. The second layer preferably contains an antioxidant. The third layer preferably contains an antioxidant. The layer containing the ultraviolet absorber (X) preferably contains an antioxidant. Only one type of antioxidant may be used, or two or more types may be used in combination.

[0174] Examples of the antioxidant include phenol-based antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants. The phenol-based antioxidants are antioxidants having a phenol skeleton. The sulfur-based antioxidants are antioxidants containing sulfur atoms. The phosphorus-based antioxidants are antioxidants containing phosphorus atoms.

[0175] The antioxidant is preferably a phenol-based antioxidant or a phosphorus-based antioxidant.

[0176] Examples of the phenolic antioxidant include 2,6-di-t-butyl-p-cresol (BHT), butylhydroxyanisole (BHA), 2,6-di-t-butyl-4-ethylphenol, stearyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,2'-methylenebis-(4-methyl-6-butylphenol), 2,2'-methylenebis-(4-ethyl-6-t-butylphenol), 4,4'-butylidene-bis-(3-methyl-6-t-butylphenol), 1,1,3-tris-(2-methyl-hydroxy-5- Examples of antioxidants include tetrakis[methylene-3-(3',5'-butyl-4-hydroxyphenyl)propionate]methane, 1,3,3-tris-(2-methyl-4-hydroxy-5-t-butylphenol)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, bis(3,3'-t-butylphenol)butyric acid glycol ester, and bis(3-t-butyl-4-hydroxy-5-methylbenzenepropanoate)ethylenebis(oxyethylene). One or more of these antioxidants are preferably used.

[0177] Examples of the phosphorus-based antioxidant include tridecyl phosphite, tris(tridecyl)phosphite, triphenyl phosphite, trinonylphenyl phosphite, bis(tridecyl)pentaerythritol diphosphite, bis(decyl)pentaerythritol diphosphite, tris(2,4-di-t-butylphenyl)phosphite, bis(2,4-di-t-butyl-6-methylphenyl)ethyl ester phosphorous acid, and 2,2'-methylenebis(4,6-di-t-butyl-1-phenyloxy)(2-ethylhexyloxy)phosphorus, etc. One or more of these antioxidants are preferably used.

[0178] Examples of commercially available antioxidants include "IRGANOX 245" manufactured by BASF, "IRGAFOS 168" manufactured by BASF, "IRGAFOS 38" manufactured by BASF, "Sumilizer BHT" manufactured by Sumitomo Chemical Co., Ltd., "H-BHT" manufactured by Sakai Chemical Industry Co., Ltd., and "IRGANOX 1010" manufactured by BASF.

[0179] In order to maintain a high visible light transmittance of the interlayer film and laminated glass for a long period of time, the content of the antioxidant is preferably 0.03 wt % or more, and more preferably 0.1 wt % or more, based on 100 wt % of the interlayer film or 100 wt % of the layer containing the antioxidant (the first layer, the second layer, the third layer, or the layer containing the ultraviolet absorber (X)). Furthermore, since the effect of adding the antioxidant becomes saturated, the content of the antioxidant is preferably 2 wt % or less, based on 100 wt % of the interlayer film or 100 wt % of the layer containing the antioxidant.

[0180] (Other Components) The interlayer film, the first layer, the second layer, the third layer, and the layer containing the ultraviolet absorber (X) may each contain components other than the above-mentioned components, as necessary. Examples of the other components include ultraviolet absorbers other than the ultraviolet absorber (X), colorants (pigments, dyes, etc.), coupling agents, dispersants, surfactants, flame retardants, antistatic agents, adhesion modifiers other than metal salts, moisture-resistant agents, fluorescent brighteners, and infrared absorbers. Each of these other components may be used alone, or two or more may be used in combination.

[0181] (Other details of the interlayer film for laminated glass) The maximum transmittance of the interlayer film at a wavelength of 300 nm or more and 350 nm or less is preferably 0.1% or less, more preferably 0.09% or less, and even more preferably 0.08% or less. If the maximum transmittance is equal to or less than the above upper limit, the visible light transmittance is even less likely to decrease even after long-term use of the interlayer film and laminated glass. The maximum transmittance of the interlayer film at a wavelength of 300 nm or more and 350 nm or less may be 0% or more.

[0182] The transmittance of the interlayer at a wavelength of 400 nm is preferably 1.5% or more, more preferably 3% or more, and even more preferably 5% or more. When the transmittance is equal to or greater than the lower limit, the visible light transmittance can be further increased.

[0183] The transmittance of the interlayer film at a wavelength of 300 nm or more and 350 nm or less, and the transmittance at a wavelength of 400 nm can be measured as follows. The interlayer film is placed between two 2.5 mm-thick clear glass sheets conforming to JIS R3202:1996 to obtain laminated glass A. The transmittance of the obtained laminated glass A at a wavelength of 300 nm or more and 350 nm or less, and the transmittance at a wavelength of 400 nm are measured. The transmittance of the laminated glass A at a wavelength of 300 nm or more and 350 nm or less, and the transmittance at a wavelength of 400 nm are defined as the transmittance of the interlayer film at a wavelength of 300 nm or more and 350 nm or less, and the transmittance at a wavelength of 400 nm, respectively. The transmittance can be measured in accordance with JIS R3211:1998 using a spectrophotometer (for example, Hitachi High-Technologies Corporation's "U-4150")

[0184] The ultraviolet transmittance Tuv of the interlayer film is preferably 0.5% or less, more preferably 0.3% or less, and even more preferably 0.1% or less. When the ultraviolet transmittance Tuv is equal to or less than the upper limit, the visible light transmittance is even less likely to decrease even when the interlayer film and laminated glass are used for a long period of time. The ultraviolet transmittance Tuv of the interlayer film may be 0% or more.

[0185] The ultraviolet transmittance Tuv of the interlayer film can be measured as follows. The interlayer film is placed between two 2.5 mm thick clear glass sheets conforming to JIS R3202:1996 to obtain laminated glass A. The transmittance of the obtained laminated glass A at a wavelength of 300 nm or more and 400 nm or less is measured. The value calculated from the transmittance of laminated glass A at a wavelength of 300 nm or more and 400 nm or less using a method conforming to ISO 9050 is defined as the ultraviolet transmittance Tuv of the interlayer film. The ultraviolet transmittance Tuv can be measured using a spectrophotometer (for example, "U-4150" manufactured by Hitachi High-Technologies Corporation) in accordance with JIS R3211:1998.

[0186] The absolute value of the difference (absolute value of ΔYI) between the yellow index YI of the interlayer film and the yellow index YI of a comparative interlayer film having the same layer structure and thickness as the interlayer film except that it does not contain a metal salt is determined. The absolute value of the difference (absolute value of ΔYI) serves as an index of the reactivity between the ultraviolet absorber and the metal salt. The absolute value of the difference (absolute value of ΔYI) is preferably 0.1 or less, more preferably 0.08 or less, and even more preferably 0.05 or less. When the absolute value of the difference (absolute value of ΔYI) is below the upper limit, changes in the color of the interlayer film are unlikely to occur due to variations in the amount of metal salt added, and adjustment of adhesive strength can be easily performed.

[0187] The yellow index YI of the interlayer film is a yellow index calculated from the total light transmittance. The yellow index of the interlayer film can be measured as follows. The interlayer film is placed between two 2.5 mm thick clear glass sheets conforming to JIS R3202:1996 to obtain laminated glass A. The total light transmittance of the obtained laminated glass A is measured. The yellow index YI of laminated glass A is calculated from the total light transmittance of laminated glass A according to JIS K7373. The yellow index YI of laminated glass A is defined as the yellow index YI of the interlayer film. The yellow index YI of the comparative interlayer film can also be determined in the same manner.

[0188] The total light transmittance of the laminated glass A is measured as follows.

[0189] Using a spectrophotometer, the laminated glass A is placed on the optical path between the light source and the integrating sphere, parallel to the normal to the optical axis and in contact with the integrating sphere, so that transmitted light is received by the integrating sphere. The total light transmittance refers to the visible light transmittance calculated from the spectral transmittance measured in this state. The total light transmittance can be measured using a spectrophotometer (for example, "U-4150" manufactured by Hitachi High-Technologies Corporation).

[0190] There are no particular limitations on the method for producing the laminated glass A. An example of the method for producing the laminated glass A is shown below. The laminated glass A is produced in order to measure the transmittance of the interlayer film at a wavelength of 300 nm or more and 350 nm or less, the transmittance at a wavelength of 400 nm, the ultraviolet transmittance Tuv, and the yellow index YI.

[0191] A laminate is obtained by sandwiching an interlayer between two 2.5 mm thick clear glass sheets conforming to JIS R3202:1996. The obtained laminate is placed in a rubber bag and degassed at a vacuum of 2.6 kPa for 20 minutes. The degassed laminate is then transferred to an oven and vacuum-pressed at 90°C for 30 minutes to pre-bond the laminate. The pre-bonded laminate is then compressed in an autoclave at 135°C and a pressure of 1.2 MPa for 20 minutes to obtain laminated glass A.

[0192] When a laminated glass product is obtained using the interlayer film according to the present invention, clear glass having a thickness of 2.5 mm conforming to JIS R3202:1996 may be used, or clear glass other than clear glass having a thickness of 2.5 mm conforming to JIS R3202:1996 may be used, or a laminated glass component other than clear glass may be used.

[0193] The intermediate film has one end and another end opposite to the one end, the one end and the other end being opposite ends of the intermediate film.

[0194] The interlayer film may be an interlayer film having the same thickness at one end and the other end, or an interlayer film having a greater thickness at the other end than at the one end. The interlayer film may be an interlayer film having a uniform thickness or an interlayer film having a varying thickness. The cross-sectional shape of the interlayer film may be rectangular or wedge-shaped.

[0195] The maximum thickness of the interlayer is preferably 0.1 mm or more, more preferably 0.25 mm or more, even more preferably 0.5 mm or more, particularly preferably 0.8 mm or more, and is preferably 3.8 mm or less, more preferably 2.0 mm or less, and even more preferably 1.5 mm or less.

[0196] From the viewpoint of practical use and of sufficiently increasing adhesive strength and penetration resistance, the maximum thickness of the surface layer of the interlayer film is preferably 0.001 mm or more, more preferably 0.2 mm or more, and even more preferably 0.3 mm or more, and is preferably 1.0 mm or less, and more preferably 0.8 mm or less.

[0197] From the viewpoint of practical use and of sufficiently increasing penetration resistance, the maximum thickness of the layer (intermediate layer) disposed between the two surface layers is preferably 0.001 mm or more, more preferably 0.1 mm or more, even more preferably 0.2 mm or more, and is preferably 0.8 mm or less, more preferably 0.6 mm or less, even more preferably 0.3 mm or less.

[0198] The distance between one end and the other end of the interlayer is preferably 3.0 m or less, more preferably 2.0 m or less, particularly preferably 1.5 m or less, and is preferably 0.5 m or more, more preferably 0.8 m or more, particularly preferably 1.0 m or more.

[0199] The interlayer film may be wound into a roll of the interlayer film. The roll may include a winding core and the interlayer film wound around the outer periphery of the winding core.

[0200] The method for producing the interlayer film is not particularly limited. In the case of a single-layer interlayer film, the method for producing the interlayer film includes extruding a resin composition using an extruder. In the case of a multi-layer interlayer film, the method for producing the interlayer film includes, for example, forming each layer using a resin composition for each layer, and then laminating the resulting layers. Furthermore, the method for producing the interlayer film includes co-extruding the resin compositions for each layer using an extruder to laminate the layers. A production method using extrusion molding is preferred because it is suitable for continuous production.

[0201] In view of excellent production efficiency of the interlayer film, it is preferable that the second layer and the third layer contain the same polyvinyl acetal resin. In view of excellent production efficiency of the interlayer film, it is more preferable that the second layer and the third layer contain the same polyvinyl acetal resin and the same plasticizer. In view of excellent production efficiency of the interlayer film, it is even more preferable that the second layer and the third layer are formed from the same resin composition.

[0202] The interlayer film preferably has an uneven shape on at least one of its two surfaces. The interlayer film more preferably has an uneven shape on both surfaces. The method for forming the uneven shape is not particularly limited, and examples thereof include lip embossing (melt fracture), embossing roll, calender roll, and profile extrusion.

[0203] (Laminated Glass) The laminated glass according to the present invention includes a first laminated glass member, a second laminated glass member, and the above-described interlayer film. In the laminated glass according to the present invention, the interlayer film is disposed between the first laminated glass member and the second laminated glass member.

[0204] FIG. 3 is a cross-sectional view that schematically shows an example of laminated glass that uses the interlayer film for laminated glass shown in FIG.

[0205] The laminated glass 31 shown in Fig. 3 includes a first laminated glass member 21, a second laminated glass member 22, and an interlayer film 11. The interlayer film 11 is disposed and sandwiched between the first laminated glass member 21 and the second laminated glass member 22.

[0206] A first laminated glass member 21 is laminated on a first surface of the interlayer film 11. A second laminated glass member 22 is laminated on a second surface opposite the first surface of the interlayer film 11. The first laminated glass member 21 is laminated on the outer surface of the second layer 2. The second laminated glass member 22 is laminated on the outer surface of the third layer 3.

[0207] FIG. 4 is a cross-sectional view that schematically shows an example of laminated glass that uses the interlayer film for laminated glass shown in FIG. 2 .

[0208] The laminated glass 31A shown in Fig. 4 includes a first laminated glass member 21, a second laminated glass member 22, and an interlayer film 11A. The interlayer film 11A is disposed and sandwiched between the first laminated glass member 21 and the second laminated glass member 22.

[0209] A first laminated glass member 21 is laminated on a first surface of the interlayer film 11A. A second laminated glass member 22 is laminated on a second surface of the interlayer film 11A opposite to the first surface.

[0210] The laminated glass may be a head-up display. When the laminated glass is a head-up display, the laminated glass has a display area for the head-up display. The display area is an area where information can be displayed well.

[0211] A head-up display system can be obtained using the head-up display. The head-up display system includes the laminated glass and a light source device for irradiating the laminated glass with light for image display. The light source device can be attached to the dashboard of a vehicle, for example. An image can be displayed by irradiating the display area of ​​the laminated glass with light from the light source device.

[0212] The first laminated glass member is preferably a first glass plate, and the second laminated glass member is preferably a second glass plate.

[0213] Examples of the first and second laminated glass members include glass plates and PET (polyethylene terephthalate) films. The laminated glass includes not only laminated glass in which an interlayer film is sandwiched between two glass plates, but also laminated glass in which an interlayer film is sandwiched between a glass plate and a PET film or the like. The laminated glass is a laminate including glass plates, and preferably includes at least one glass plate. It is preferable that the first laminated glass member and the second laminated glass member are each a glass plate or a PET film, and that the laminated glass includes a glass plate as at least one of the first laminated glass member and the second laminated glass member. It is particularly preferable that both the first and second laminated glass members are glass plates.

[0214] Examples of the glass plate include inorganic glass and organic glass. Examples of the inorganic glass include float glass, heat-absorbing glass, heat-reflecting glass, polished glass, patterned glass, lined glass, and green glass. The organic glass is a synthetic resin glass that replaces inorganic glass. Examples of the organic glass include polycarbonate plates and poly(meth)acrylic resin plates. Examples of the poly(meth)acrylic resin plates include polymethyl(meth)acrylate plates.

[0215] The thickness of each of the first laminated glass member and the second laminated glass member is preferably 1 mm or more and 5 mm or less, more preferably 3 mm or less. When the laminated glass member is a glass plate, the thickness of the glass plate is preferably 0.5 mm or more, more preferably 0.7 mm or more, and preferably 5 mm or less, more preferably 3 mm or less. When the laminated glass member is a PET film, the thickness of the PET film is preferably 0.03 mm or more and preferably 0.5 mm or less.

[0216] The method for producing the laminated glass is not particularly limited. First, an interlayer film is sandwiched between the first laminated glass member and the second laminated glass member to obtain a laminate. Next, the air remaining between the first laminated glass member, the second laminated glass member, and the interlayer film is removed, for example, by passing the obtained laminate through a pressure roll or placing it in a rubber bag and suctioning it under reduced pressure. Thereafter, a pre-bonded laminate is obtained by pre-bonding at approximately 70°C to 110°C. Next, the pre-bonded laminate is placed in an autoclave or pressed at approximately 120°C to 150°C and a pressure of 1 MPa to 1.5 MPa. In this manner, a laminated glass can be obtained.

[0217] The interlayer film and the laminated glass can be used in automobiles, railway vehicles, aircraft, ships, buildings, etc. The interlayer film and the laminated glass can also be used for applications other than these. The interlayer film and the laminated glass are preferably interlayer films and laminated glass for vehicles or buildings, and more preferably interlayer films and laminated glass for vehicles. The interlayer film and the laminated glass can be used for automobile windshields, side windows, rear windows, roof glass, backlight glass, etc. The interlayer film and the laminated glass are preferably used in automobiles. The interlayer film is preferably used to obtain laminated glass for automobiles.

[0218] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0219] The polyvinyl acetal resin used was acetalized using n-butylaldehyde having a carbon number of 4. The degree of acetalization (degree of butyralization), degree of acetylation, and hydroxyl group content of the polyvinyl acetal resin were measured by a method conforming to JIS K6728 "Testing Methods for Polyvinyl Butyral." Note that when measured by ASTM D1396-92, the values ​​shown were similar to those obtained by the method conforming to JIS K6728 "Testing Methods for Polyvinyl Butyral."

[0220] The following materials were prepared:

[0221] (Thermoplastic resin) Polyvinyl acetal resin (polyvinyl butyral resin, average degree of polymerization 1700, hydroxyl group content 30 mol%, acetylation degree 1 mol%, acetalization degree (butyralization degree) 69 mol%) Polyvinyl acetal resin (polyvinyl butyral resin, average degree of polymerization 3000, hydroxyl group content 22 mol%, acetylation degree 13 mol%, acetalization degree (butyralization degree) 65 mol%) Polyvinyl acetal resin (polyvinyl butyral resin, average degree of polymerization 1700, hydroxyl group content 30.5 mol%, acetylation degree 1 mol%, acetalization degree (butyralization degree) 68.5 mol%)

[0222] (Plasticizer) Triethylene glycol di-2-ethylhexanoate (3GO)

[0223] (Ultraviolet Absorber) Ultraviolet absorber (X): Ultraviolet absorber represented by the above formula (X11) ("Tinuvin 234" manufactured by BASF) Ultraviolet absorber represented by the above formula (X12) ("Tinuvin 640" manufactured by BASF) Ultraviolet absorber represented by the above formula (X13) ("Eversorb 88" manufactured by Everlight Chemical)

[0224] Ultraviolet absorbers not corresponding to ultraviolet absorber (X): 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole ("Tinuvin 329" manufactured by BASF) 2-(5-tert-butyl-2-hydroxyphenyl)benzotriazole ("Tinuvin PS" manufactured by BASF) 2,2',4,4'-tetrahydroxybenzophenone ("SEESORB106" manufactured by Shipro Chemicals, an ultraviolet absorber having a benzophenone skeleton but not a benzotriazole skeleton)

[0225] (Metal Salts) Metal Salt 1: 50:50 (weight ratio) mixture of magnesium 2-ethylbutyrate and magnesium acetate Metal Salt 2: Potassium acetate

[0226] (Antioxidant) BHT (2,6-di-t-butyl-p-cresol)

[0227] Example 1 Preparation of composition for forming interlayer film: The following components were blended and thoroughly kneaded with a mixing roll to obtain a composition for forming an interlayer film.

[0228] Polyvinyl butyral resin (average degree of polymerization 1700, hydroxyl group content 30 mol%, acetylation degree 1 mol%, acetalization degree (butyralization degree) 69 mol%): 100 parts by weight Triethylene glycol di-2-ethylhexanoate (3GO): 40 parts by weight UV absorber represented by the above formula (X12): 0.4 parts by weight Metal salt 1 in an amount such that the magnesium content is 0.038 parts by weight (metal salt 1 in an amount such that the magnesium content in the resulting interlayer film is 60 ppm) Antioxidant (BHT) in an amount such that the magnesium content in the resulting interlayer film is 0.2% by weight

[0229] Preparation of Interlayer Film: A single-layer interlayer film (thickness 760 μm) including only the first layer was prepared by extruding the composition for forming the interlayer film using an extruder.

[0230] Preparation of laminated glass: The obtained interlayer film was sandwiched between two 2.5 mm thick clear glass sheets (300 mm long x 300 mm wide) conforming to JIS R3202:1996 to obtain a laminate. The obtained laminate was placed in a rubber bag and degassed at a vacuum of 2.6 kPa for 20 minutes, then transferred to an oven in the degassed state and held at 90°C for 30 minutes to vacuum press the laminate to pre-bond it. The pre-bonded laminate was then pressed in an autoclave at 135°C and a pressure of 1.2 MPa for 20 minutes to obtain a laminated glass. The obtained laminated glass corresponds to the laminated glass A described above.

[0231] (Examples 2 to 6 and Comparative Examples 1 to 9) Single-layer interlayer films (thickness: 760 μm) were prepared in the same manner as in Example 1, except that the type and content of the ultraviolet absorber and the type and content of the metal salt were changed as shown in Tables 2 to 4. The antioxidants used were the same type and in the same amount as in Example 1.

[0232] Example 7 Preparation of resin composition for forming first layer: The following components were blended and thoroughly kneaded with a mixing roll to obtain a resin composition for forming the first layer.

[0233] Polyvinyl butyral resin (average degree of polymerization 3000, hydroxyl group content 22 mol%, acetylation degree 13 mol%, acetalization degree 65 mol%): 100 parts by weight Triethylene glycol di-2-ethylhexanoate (3GO): 40 parts by weight UV absorber represented by the above formula (X12): 0.4 parts by weight Metal salt 1 in an amount such that the magnesium content is 0.038 parts by weight (metal salt 1 in an amount such that the magnesium content in the resulting first layer is 60 ppm) Antioxidant (BHT) in an amount such that the magnesium content in the resulting first layer is 0.2% by weight

[0234] Preparation of resin composition for forming second layer and third layer: The following components were blended and thoroughly kneaded with a mixing roll to obtain a resin composition for forming the second layer and the third layer.

[0235] Polyvinyl butyral resin (average degree of polymerization 1700, hydroxyl group content 30.5 mol%, acetylation degree 1 mol%, acetalization degree 68.5 mol%): 100 parts by weight Triethylene glycol di-2-ethylhexanoate (3GO): 40 parts by weight Ultraviolet absorber represented by the above formula (X12): 0.4 parts by weight Metal salt 1 in an amount such that the magnesium content is 0.038 parts by weight (metal salt 1 in an amount such that the magnesium content in the resulting second and third layers is 60 ppm) Antioxidant (BHT) in an amount such that the magnesium content in the resulting second and third layers is 0.2% by weight

[0236] Preparation of interlayer film: The resin composition for forming the first layer and the resin compositions for forming the second and third layers were co-extruded using a co-extruder to obtain an interlayer film (thickness 760 μm) having a three-layer structure (second layer / first layer / third layer).

[0237] Preparation of Laminated Glass: Except for using the obtained interlayer film, a laminated glass was obtained in the same manner as in Example 1. The obtained laminated glass corresponds to the laminated glass A described above.

[0238] Examples 8 and 9 Interlayer films (thickness 760 μm) having a three-layer structure (second layer / first layer / third layer) were prepared in the same manner as in Example 7, except that the type and content of the ultraviolet absorber and the type and content of the metal salt were changed as shown in Table 5. The same type and amount of antioxidant as in Example 7 were used.

[0239] (Evaluation) (1) Maximum transmittance of interlayer film in a wavelength range of 300 nm or more and 350 nm or less The maximum transmittance of the interlayer film in a wavelength range of 300 nm or more and 350 nm or less was determined by measuring the transmittance of the obtained laminated glass (laminated glass A) in a wavelength range of 300 nm or more and 350 nm or less using a spectrophotometer ("U-4150" manufactured by Hitachi High-Technologies Corporation) according to the method described above.

[0240] (2) Transmittance of Interlayer Film at a Wavelength of 400 nm The transmittance of the interlayer film at a wavelength of 400 nm was determined by measuring the transmittance of the obtained laminated glass (laminated glass A) at a wavelength of 400 nm using a spectrophotometer (U-4150 manufactured by Hitachi High-Technologies Corporation) according to the method described above.

[0241] (3) Ultraviolet transmittance Tuv of interlayer film The ultraviolet transmittance Tuv of the interlayer film was determined by measuring the transmittance of the obtained laminated glass (laminated glass A) in the wavelength range of 300 nm or more and 400 nm or less using a spectrophotometer (U-4150 manufactured by Hitachi High-Technologies Corporation) according to the method described above.

[0242] [Criteria for determining ultraviolet transmittance Tuv of interlayer film] ◯: The ultraviolet transmittance Tuv of the interlayer film is 0.5% or less. ×: The ultraviolet transmittance Tuv of the interlayer film is more than 0.5%.

[0243] (4) Yellow Index YI of Interlayer Film The total light transmittance of the obtained laminated glass (laminated glass A) was measured by the method described above using a spectrophotometer (U-4150 manufactured by Hitachi High-Technologies Corporation), to determine the yellow index YI of the interlayer film.

[0244] (5) Reactivity of UV absorber with metal salt (absolute value of ΔYI) For interlayer films containing the same type of UV absorber, the change in yellow index YI (ΔYI) between the interlayer films in the presence or absence of metal salt was determined. That is, ΔYI is the value obtained by subtracting the yellow index YI of the reference interlayer film (interlayer film not containing metal salt) from the yellow index YI of the interlayer film to be evaluated. More specifically, ΔYI is a value calculated by the following formula. The combinations of the interlayer film to be evaluated and the reference interlayer film are as follows. Note that the closer the absolute value of ΔYI is to 0, the lower the reactivity between the UV absorber and metal salt is, meaning that the interlayer film is less likely to yellow.

[0245] ΔYI = (YI of the interlayer film to be evaluated) - (YI of the reference interlayer film)

[0246] More specifically, it is as follows.

[0247] ΔYI = (YI of the interlayer films obtained in Examples 1 to 4) - (YI of the interlayer film obtained in Comparative Example 1) ΔYI = (YI of the interlayer film obtained in Example 5) - (YI of the interlayer film obtained in Comparative Example 2) ΔYI = (YI of the interlayer film obtained in Example 6) - (YI of the interlayer film obtained in Comparative Example 3) ΔYI = (YI of the interlayer film obtained in Example 7) - (YI of the interlayer film obtained in Comparative Example 1) ΔYI = (YI of the interlayer film obtained in Example 8) - (YI of the interlayer film obtained in Comparative Example 2) ΔYI = (YI of the interlayer film obtained in Example 9) - (YI of the interlayer film obtained in Comparative Example 3) ΔYI = (YI of the interlayer film obtained in Comparative Example 4) - (YI of the interlayer film obtained in Comparative Example 5) ΔYI = (YI of the interlayer film obtained in Comparative Example 6) - (YI of the interlayer film obtained in Comparative Example 7) ΔYI=(YI of the interlayer film obtained in Comparative Example 8)−(YI of the interlayer film obtained in Comparative Example 9)

[0248] [Criteria for the reactivity (absolute value of ΔYI) between an ultraviolet absorber and a metal salt] ○: Absolute value of ΔYI is 0.1 or less ×: Absolute value of ΔYI exceeds 0.1

[0249] (6) Adhesion between interlayer film and laminated glass member (measurement of pummel value) The obtained laminated glass was left to stand in an environment at a temperature of -18°C ± 0.6°C for 16 hours, and then the center of the laminated glass (a portion of 150 mm length × 150 mm width) was struck with a hammer with a head of 0.45 kg to crush the glass into particles of 6 mm or less. The degree of film exposure after partial peeling of the glass was measured, and the pummel value was calculated according to Table 1 below. The pummel value is a value used to measure the degree of adhesion between the interlayer film and the glass plate, and is a value specified by the degree of film exposure (area %) after partial peeling of the glass, as defined in Table 1. A pummel value of 2 to 7 was evaluated as "Good", and any other value was evaluated as "Poor".

[0250]

[0251] The interlayer structure and results are shown in Tables 2 to 5 below.

[0252]

[0253]

[0254]

[0255]

[0256] REFERENCE SIGNS LIST 1... First layer 1a... First surface 1b... Second surface 2... Second layer 3... Third layer 11, 11A... Interlayer film 21... First laminated glass member 22... Second laminated glass member 31, 31A... Laminated glass

Claims

1. An interlayer for laminated glass having a single-layer structure or a structure of two or more layers, An interlayer for laminated glass comprising an ultraviolet absorber represented by the following formula (X) and a metal salt. 【Chemistry 1】 In the above formula (X), R １ represents any group, R ２ ~R ８ Each of these represents a hydrogen atom, an atom other than a hydrogen atom, or any group.

2. The interlayer film for laminated glass according to claim 1, comprising a layer containing the ultraviolet absorber and the metal salt.

3. In the above formula (X), R １ The interfilm for laminated glass according to claim 1, wherein the interfilm is an alkyl group, aryl group, alkoxy group, aryloxy group, acyloxy group, alkylamino group, anilino group, acylamino group, alkylsulfonylamino group, arylsulfonylamino group, alkylthio group, or arylthio group.

4. The interlayer film for laminated glass according to claim 1, wherein the molecular weight of the ultraviolet absorber is 355 or more.

5. The interlayer film for laminated glass according to claim 1, wherein the ultraviolet absorber comprises an ultraviolet absorber represented by the following formula (X11), the following formula (X12), or the following formula (X13). 【Chemistry 2】 【Transformation 3】 【Chemistry 4】

6. The interlayer film for laminated glass according to claim 1, wherein the metal salt comprises an alkali metal salt or an alkaline earth metal salt.

7. The interlayer film for laminated glass according to claim 1, wherein the metal salt comprises a magnesium salt of an organic acid having a branched structure.

8. The interlayer film for laminated glass according to claim 1, wherein the metal salt is a metal salt other than a magnesium salt of an organic acid having a branched structure, and includes a metal salt of an organic acid having 2 to 8 carbon atoms.

9. An interlayer for laminated glass having a structure of two or more layers, The interlayer for laminated glass according to claim 1, wherein the interlayer comprises a first layer and a second layer disposed on the first surface side of the first layer.

10. The second layer is the surface layer of the interlayer, The interlayer for laminated glass according to claim 9, wherein the second layer comprises the ultraviolet absorber and the metal salt.

11. An interlayer for laminated glass having a structure of three or more layers, The interlayer for laminated glass according to claim 9, wherein the interlayer comprises a third layer disposed on the second surface side of the first layer opposite to the first surface.

12. An interlayer for laminated glass having a structure of three or more layers, The interlayer comprises a third layer disposed on the second surface side of the first layer opposite to the first surface, The second layer and the third layer are, respectively, surface layers of the interlayer. The interlayer for laminated glass according to claim 9, wherein the second layer and the third layer each contain the ultraviolet absorber and the metal salt.

13. An interlayer for laminated glass having a structure of three or more layers, The interlayer comprises a first layer, a second layer disposed on the first surface side of the first layer, and a third layer disposed on the second surface side of the first layer opposite to the first surface. The first layer comprises a thermoplastic resin, The second layer and the third layer are, respectively, surface layers of the interlayer. Each of the second and third layers comprises a thermoplastic resin, an ultraviolet absorber represented by the following formula (X12) or formula (X13), and the metal salt. The interlayer for laminated glass according to claim 1, wherein the thermoplastic resin in the first layer and the thermoplastic resin in the second layer are different. 【Transformation 5】 【Transformation 6】

14. The interlayer for laminated glass according to claim 13, wherein the second layer and the third layer each contain an ultraviolet absorber represented by formula (X12).

15. The interlayer for laminated glass according to claim 13, wherein the thermoplastic resin in the first layer and the thermoplastic resin in the third layer are different.

16. The second layer and the third layer each contain an ultraviolet absorber represented by formula (X12), The interlayer for laminated glass according to claim 13, wherein the thermoplastic resin in the first layer and the thermoplastic resin in the third layer are different.

17. The layer comprises the ultraviolet absorber and the metal salt, An interlayer for laminated glass according to any one of claims 1 to 16, wherein in a layer comprising the ultraviolet absorber and the metal salt, the weight ratio of the metal content in the metal salt to the content of the ultraviolet absorber is 4 or more and 50 or less.

18. An interlayer for laminated glass according to any one of claims 1 to 16, wherein the maximum transmittance of the interlayer at a wavelength of 300 nm to 350 nm is 0.1% or less.

19. An interlayer for laminated glass according to any one of claims 1 to 16, wherein the ultraviolet transmittance Tuv of the interlayer is 0.5% or less.

20. An interlayer for laminated glass according to any one of claims 1 to 16, wherein the transmittance of the interlayer at a wavelength of 400 nm is 1.5% or more.

21. An interlayer for laminated glass according to any one of claims 1 to 16, wherein the absolute value of the difference between the yellow index YI of the interlayer and the yellow index YI of a comparative interlayer having the same layer structure and thickness as the interlayer except that it does not contain a metal salt is 0.1 or less.

22. The first laminated glass member, A second laminated glass member, The laminated glass interfilm is as described in any one of claims 1 to 16, A laminated glass in which the interlayer film for laminated glass is disposed between the first laminated glass member and the second laminated glass member.

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