Interlayer film for laminated glass, method for producing interlayer film for laminated glass, and laminated glass

Abstract

Provided is an intermediate film for laminated glass in which the haze value can be suppressed to a low level even when a heat resistance test is performed on laminated glass at 100 DEG C even if the intermediate film is provided with a polyethylene terephthalate film. The interlayer for laminated glass according to the present invention comprises, in this order, a first resin layer containing a thermoplastic resin, a polyethylene terephthalate film, and a second resin layer containing a thermoplastic resin, wherein the ratio of the absorbance (A) at a wavelength of 1930 nm to the absorbance (B) at a wavelength of 1705 nm is 0.50 or less.

Description

Technical Field

[0001] The present invention relates to an interlayer film for laminated glass and a method for manufacturing the same for obtaining laminated glass. Further, the present invention relates to laminated glass using the interlayer film for laminated glass. Background Art

[0002] Even when laminated glass is damaged by an external impact, the amount of scattered glass fragments is small, and it has excellent safety. Therefore, laminated glass is widely used in automobiles, railway vehicles, airplanes, ships, buildings, and the like. Laminated glass is manufactured by sandwiching an interlayer film between a pair of glass plates.

[0003] In order to improve heat insulation or strength, an interlayer film having a polyethylene terephthalate film is sometimes used. An interlayer film having a polyethylene terephthalate film is disclosed, for example, in Patent Document 1 below.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2010-265165 Summary of the Invention

[0007] Technical Problem to be Solved by the Invention

[0008] As a test of laminated glass using an interlayer film, a heat resistance test at 100°C may be performed in which the laminated glass is left standing in an environment of 100°C for a given period.

[0009] However, for laminated glass using an existing interlayer film having a polyethylene terephthalate film, when a heat resistance test at 100°C is performed, the haze value of the laminated glass becomes high. It should be noted that the problem of the high haze value of the laminated glass when performing the heat resistance test at 100°C occurs only when using an interlayer film having a polyethylene terephthalate film, and does not occur when using an interlayer film not having a polyethylene terephthalate film.

[0010] An object of the present invention is to provide an interlayer film for laminated glass in which, even if the interlayer film has a polyethylene terephthalate film, the haze value can be suppressed to a low level when performing a heat resistance test at 100°C on the laminated glass. Further, an object of the present invention is to provide a method for manufacturing the interlayer film for laminated glass. Further, an object of the present invention is to provide laminated glass using the interlayer film for laminated glass.

[0011] Technical Means for Solving the Problem

[0012] In the present specification, the following interlayer film for laminated glass, method for manufacturing an interlayer film for laminated glass, and laminated glass are disclosed.

[0013] Item 1. An interlayer film for laminated glass, which successively includes:

[0014] A first resin layer containing a thermoplastic resin,

[0015] A polyethylene terephthalate film, and

[0016] A second resin layer containing a thermoplastic resin,

[0017] The ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm of the interlayer film for laminated glass is 0.50 or less.

[0018] Item 2. The interlayer film for laminated glass according to Item 1, wherein

[0019] The polyethylene terephthalate film is a multilayer polyethylene terephthalate film having two or more polyethylene terephthalate layers and no metal layer, or

[0020] The polyethylene terephthalate film is a polyethylene terephthalate film containing a metal layer having a polyethylene terephthalate layer and a metal layer.

[0021] Item 3. The interlayer film for laminated glass according to Item 1 or 2, wherein

[0022] The thermoplastic resin contained in the first resin layer contains a polyvinyl acetal resin,

[0023] The thermoplastic resin contained in the second resin layer contains a polyvinyl acetal resin.

[0024] Item 4. A method for manufacturing the interlayer film for laminated glass according to any one of Items 1 to 3, which includes:

[0025] A step of obtaining a laminate, which successively includes: a layer for forming a first resin layer containing a thermoplastic resin, a polyethylene terephthalate film, and a layer for forming a second resin layer containing a thermoplastic resin; and

[0026] A step of curing the laminate in such a manner that the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm in the obtained interlayer film is 0.50 or less.

[0027] Item 5. A method for manufacturing the interlayer film for laminated glass according to any one of Items 1 to 3, which includes:

[0028] A step of curing at least one of a layer forming layer for a first resin layer containing a thermoplastic resin and a layer forming layer for a second resin layer containing a thermoplastic resin such that in the resulting intermediate film, the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm is 0.50 or less.

[0029] Item 6. An insulating glass, comprising:

[0030] A first insulating glass component;

[0031] A second insulating glass component; and

[0032] The intermediate film for insulating glass according to any one of Items 1 to 3,

[0033] The intermediate film for insulating glass is disposed between the first insulating glass component and the second insulating glass component.

[0034] Advantages of the Invention

[0035] The intermediate film for insulating glass of the present invention sequentially includes a first resin layer containing a thermoplastic resin, a polyethylene terephthalate film, and a second resin layer containing a thermoplastic resin, and the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm of the intermediate film for insulating glass is 0.50 or less. In the intermediate film for insulating glass of the present invention, due to the above configuration, even if the intermediate film has a polyethylene terephthalate film, when performing a heat resistance test on the insulating glass at 100 °C, the haze value can be suppressed to a low level. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Figure 1 is a diagram for explaining the calculation method of the absorbance A at a wavelength of 1930 nm and the absorbance B at a wavelength of 1705 nm.

[0037] Figure 2 Figure 2 is a cross-sectional view schematically showing the intermediate film for insulating glass according to an embodiment of the present invention.

[0038] Figure 3 Figure 3 is a cross-sectional view schematically showing an example of an insulating glass using the Figure 2 shown intermediate film for insulating glass. DETAILED DESCRIPTION OF THE INVENTION

[0039] Hereinafter, the present invention will be described in detail.

[0040] (Intermediate film for insulating glass)

[0041] ​​​​​​The interlayer film for laminated glass of the present invention (hereinafter sometimes simply referred to as "interlayer film" in this specification) is used for laminated glass.

[0042] The interlayer film sequentially includes: a first resin layer containing a thermoplastic resin, a polyethylene terephthalate film, and a second resin layer containing a thermoplastic resin. In the interlayer film, the first resin layer is disposed on the first surface side of the polyethylene terephthalate film, and the second resin layer is disposed on the second surface side of the polyethylene terephthalate film opposite to the first surface.

[0043] The interlayer film may have a three-layer structure including the first resin layer, the polyethylene terephthalate film, and the second resin layer. The interlayer film may have a structure of three or more layers, may have a structure of ten or less layers, and may also have a structure of five or less layers. It should be noted that when the polyethylene terephthalate film included in the interlayer film has multiple layers, in the counting of the number of layers of the interlayer film, the polyethylene terephthalate film with multiple layers is counted as one layer. The polyethylene terephthalate film with multiple layers can be regarded as a single-layer component as a whole in the interlayer film.

[0044] In the interlayer film, the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm (absorbance A / absorbance B) is 0.50 or less.

[0045] The absorbance A corresponds to the absorbance of water, and the absorbance B corresponds to the absorbance of methylene. The present inventors have found that if the ratio (absorbance A / absorbance B) is 0.50 or less, even if the interlayer film includes a polyethylene terephthalate film, when performing a heat resistance test on the laminated glass at 100 °C, the haze value can be suppressed to a low level. Therefore, in the laminated glass using the interlayer film, the haze value of the laminated glass is not likely to increase even when used in a high-temperature environment, for example.

[0046] The ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm (absorbance A / absorbance B) is preferably 0.06 or more, more preferably 0.10 or more, preferably 0.48 or less, more preferably 0.45 or less, still more preferably 0.40 or less, further preferably 0.35 or less, still more preferably 0.30 or less, particularly preferably 0.25 or less, and most preferably 0.20 or less. When the ratio (absorbance A / absorbance B) is above the lower limit, the adhesiveness between the interlayer film and the laminated glass components can be further improved. When the ratio (absorbance A / absorbance B) is below the upper limit, the effects of the present invention can be more effectively exerted.

[0047] The absorbance A at a wavelength of 1930 nm is preferably 0.01 or more, more preferably 0.02 or more, preferably 0.10 or less, more preferably 0.08 or less, and further preferably 0.05 or less. When the absorbance A is at or above the lower limit, the adhesion between the intermediate film and the laminated glass component can be further improved. When the absorbance A is at or below the upper limit, the effects of the present invention can be more effectively exerted.

[0048] The absorbance A and the absorbance B are measured by the following methods respectively.

[0049] (1) Preparation of laminated glass X

[0050] The intermediate film is disposed between two pieces of transparent glass according to JIS R3202:1996 to prepare laminated glass X (laminated glass for absorbance measurement). The laminated glass X is preferably prepared in the following manner.

[0051] The intermediate film is sandwiched between two pieces of transparent glass with a thickness of 2 mm according to JIS R3202:1996 to obtain a laminate. The obtained laminate is placed in a rubber bag, degassed at a vacuum degree of 2.6 kPa for 20 minutes, then transferred to an oven in a degassed state, and then vacuum-pressed at 90 °C for 30 minutes to pre-bond the laminate. In an autoclave, the pre-bonded laminate is pressed at 135 °C and a pressure of 1.2 MPa for 20 minutes to obtain laminated glass X.

[0052] (2) Measurement of absorbance

[0053] In the obtained laminated glass X, the position 3 cm from one end to the other end is taken as the first position, and the position 5 cm from one end to the other end is taken as the second position. The one end and the other end are the end portions on both sides of the laminated glass X that face each other. Using a near-infrared spectrophotometer (for example, "V-570" manufactured by JASCO Corporation), the absorbances at the first position and the second position of the laminated glass X are measured under the conditions of a bandwidth of 2 nm, a scanning speed of 1000 nm / minute, a scanning range of 1550 nm to 2050 nm, and a data acquisition interval of 0.5 nm. At the same wavelength, the absorbance at the first position and the absorbance at the second position are averaged. An absorbance spectrum is made from the averaged absorbance.

[0054] In the made absorbance spectrum, the line connecting the position of the absorbance at a wavelength of 1873 nm and the position of the absorbance at a wavelength of 1984 nm is taken as the baseline for absorbance A. The absolute value of the difference between the absorbance at a wavelength of 1930 nm on the baseline for absorbance A and the absorbance at a wavelength of 1930 nm on the made absorbance spectrum is defined as the absorbance A of the intermediate film at a wavelength of 1930 nm.

[0055] In the produced absorbance spectrum, the position of the absorbance at a wavelength of 1670 nm is used as the absorbance B baseline. The absolute value of the difference between the absorbance at a wavelength of 1670 nm on the produced absorbance spectrum and the absorbance at a wavelength of 1705 nm on the produced absorbance spectrum is defined as the absorbance B at a wavelength of 1705 nm of the intermediate film.

[0056] Figure 1 It is a diagram for explaining the calculation method of the absorbance A at a wavelength of 1930 nm and the absorbance B at a wavelength of 1705 nm. In Figure 1 it shows an example of an absorbance spectrum made from the absorbance obtained by averaging the absorbance at the first position and the absorbance at the second position. As Figure 1 shown, the absorbance A is the absolute value of the difference between the absorbance at a wavelength of 1930 nm on the baseline and the absorbance at a wavelength of 1930 nm on the absorbance spectrum. In addition, as Figure 1 shown, the absolute value of the difference between the absorbance at a wavelength of 1670 nm on the absorbance spectrum and the absorbance at a wavelength of 1705 nm on the absorbance spectrum is the absorbance B.

[0057] It should be noted that the laminated glass X is prepared for measuring the absorbance. In the intermediate film, laminated glass (laminated glass products) can be prepared using laminated glass components other than two pieces of transparent glass according to JIS R3202:1996, or laminated glass (laminated glass products) can be prepared using laminated glass components other than transparent glass.

[0058] The intermediate film with a ratio (absorbance A / absorbance B) of 0.50 or less can be obtained, for example, by the following method for manufacturing the intermediate film.

[0059] Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

[0060] Figure 2 It is a cross-sectional view schematically showing an intermediate film for laminated glass according to an embodiment of the present invention.

[0061] Figure 2The intermediate film 11 shown is used to obtain laminated glass. The intermediate film 11 is an intermediate film for laminated glass. The intermediate film 11 includes a polyethylene terephthalate film 1, a first resin layer 2, and a second resin layer 3. The first resin layer 2 is disposed and laminated on the first surface 1a side of the polyethylene terephthalate film 1. The second resin layer 3 is disposed and laminated on the second surface 1b side of the polyethylene terephthalate film 1 opposite to the first surface 1a. The polyethylene terephthalate film 1 is an intermediate layer. The first resin layer 2 and the second resin layer 3 are respectively protective layers, and are surface layers in the present embodiment. The polyethylene terephthalate film 1 is disposed and sandwiched between the first resin layer 2 and the second resin layer 3. Therefore, the intermediate film 11 has a multilayer structure (the first resin layer 2 / polyethylene terephthalate film 1 / second resin layer 3) in which the first resin layer 2, the polyethylene terephthalate film 1, and the second resin layer 3 are laminated in sequence.

[0062] It should be noted that other layers may be respectively disposed between the first resin layer 2 and the polyethylene terephthalate film 1, and between the polyethylene terephthalate film 1 and the second resin layer 3. The first resin layer 2 and the polyethylene terephthalate film 1, and the polyethylene terephthalate film 1 and the second resin layer 3 are preferably directly laminated respectively. As other layers, an adhesive layer can be cited.

[0063] Hereinafter, other details of the components constituting the intermediate film and the laminated glass of the present invention will be described.

[0064] (Polyethylene terephthalate film)

[0065] The polyethylene terephthalate film (PET film) contains polyethylene terephthalate. The heat insulation or strength can be improved by the intermediate film having a polyethylene terephthalate film. In addition, the transfer of components contained in one resin layer to the other resin layer can be effectively prevented by the intermediate film having a polyethylene terephthalate film.

[0066] As the polyethylene terephthalate film, a single-layer polyethylene terephthalate film having one layer of polyethylene terephthalate layer and no metal layer, a multi-layer polyethylene terephthalate film having two or more layers of polyethylene terephthalate layer and no metal layer, and a polyethylene terephthalate film containing a metal layer having a polyethylene terephthalate layer and a metal layer can be cited.

[0067] The polyethylene terephthalate film can be the single-layer polyethylene terephthalate film, the multi-layer polyethylene terephthalate film, or the polyethylene terephthalate film containing a metal layer.

[0068] From the viewpoint of further improving heat insulation, the polyethylene terephthalate film is preferably the multilayer polyethylene terephthalate film or the polyethylene terephthalate film containing a metal layer.

[0069] The multilayer polyethylene terephthalate film has two or more polyethylene terephthalate layers. The multilayer polyethylene terephthalate film may have 2, 2 or more, 3 or more, 5 or more, 1000 or less, 100 or less, 50 or less polyethylene terephthalate layers.

[0070] The polyethylene terephthalate film containing a metal layer may have 1, 2, 2 or more, 3 or more, 5 or more, 1000 or less, 100 or less, 50 or less polyethylene terephthalate layers.

[0071] The polyethylene terephthalate film containing a metal layer may have 1, 2, 2 or more, 3 or more, 5 or more, 1000 or less, 100 or less, 50 or less metal layers. As the material of the metal layer, aluminum, copper, silver, gold, palladium and alloys containing them can be cited. The material of the metal layer can use only one kind, or two or more kinds can be used in combination.

[0072] In the polyethylene terephthalate film containing a metal layer, it is preferred that the metal layer is arranged on the outer surface of the polyethylene terephthalate layer. In the polyethylene terephthalate film containing a metal layer, it is preferred that at least one surface layer is the metal layer.

[0073] In the polyethylene terephthalate film containing a metal layer, it is preferred that the metal layer is a metal sputtering layer. The metal sputtering layer can be formed by metal sputtering. A coating of a metal or a mixed oxide of a metal can also be given to both sides or one side of the metal layer. As the material of the coating, ZnO, Al2O3, Ga2O3, InO3, MgO, Ti, NiCr, Cu, etc. can be cited.

[0074] The polyethylene terephthalate film containing a metal layer may have a dielectric layer. In the polyethylene terephthalate film containing a metal layer, any number of metal layers and dielectric layers can be alternately laminated on the polyethylene terephthalate layer. It should be noted that in the polyethylene terephthalate film containing a metal layer having a dielectric layer, it is preferred that all the metal layers and dielectric layers are alternately laminated, and there may also be a structure part where a part is not alternately laminated, such as metal layer / dielectric layer / metal layer / dielectric layer / metal layer / metal layer / dielectric layer / metal layer. As the material of the dielectric layer, indium oxide, etc. can be cited, for example.

[0075] (The first resin layer and the second resin layer)

[0076] <Thermoplastic resin>

[0077] The first resin layer contains a thermoplastic resin (hereinafter sometimes referred to as thermoplastic resin (1)). The thermoplastic resin (1) preferably contains a polyvinyl acetal resin. The first resin layer preferably contains a polyvinyl acetal resin as the thermoplastic resin (1). The second resin layer contains a thermoplastic resin (hereinafter sometimes referred to as thermoplastic resin (2)). The thermoplastic resin (2) preferably contains a polyvinyl acetal resin. The second resin layer preferably contains a polyvinyl acetal resin as the thermoplastic resin (2).

[0078] The thermoplastic resin (1) and the thermoplastic resin (2) may be the same or different. Each of the thermoplastic resin (1) and the thermoplastic resin (2) may be used alone or two or more kinds may be used in combination.

[0079] In the following description, for the common constitution of the thermoplastic resin (1) and the thermoplastic resin (2), it will be described only as "thermoplastic resin".

[0080] Examples of the thermoplastic resin include polyvinyl acetal resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, polyurethane resin, polyvinyl alcohol resin, polyolefin resin, polyvinyl acetate resin, polystyrene resin, and ionomer resin. Thermoplastic resins other than these may also be used.

[0081] The thermoplastic resin is preferably a polyvinyl acetal resin. By using a polyvinyl acetal resin and a plasticizer in combination, the adhesive force of the resin layer to other layers such as laminated glass members and polyethylene terephthalate films becomes even higher.

[0082] 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 is obtained, for example, by saponifying polyvinyl acetate. The saponification degree of the polyvinyl alcohol is usually in the range of 70 mol% to 99.9 mol%.

[0083] The average degree of polymerization of the polyvinyl alcohol (PVA) is preferably 200 or more, more preferably 500 or more, still more preferably 1500 or more, further preferably 1600 or more, particularly preferably 2600 or more, most preferably 2700 or more, and preferably 5000 or less, more preferably 4000 or less, still 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 molding of the resin layer becomes easier.

[0084] The average degree of polymerization of the polyvinyl alcohol is determined by the method according to JIS K6726 "Test Method for Polyvinyl Alcohol".

[0085] The number of carbon atoms of 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 of the acetal group in the polyvinyl acetal resin is preferably 3 to 5, more preferably 3 or 4. When the number of carbon atoms of the acetal group in the polyvinyl acetal resin is 3 or more, the glass transition temperature of the resin layer is sufficiently reduced.

[0086] The aldehyde is not particularly limited. Generally, an aldehyde having 1 to 10 carbon atoms is preferably used. Examples of the aldehyde having 1 to 10 carbon atoms include propionaldehyde, n-butanal, isobutanal, n-pentanal, 2-ethylbutanal, n-hexanal, n-octanal, n-nonanal, n-decanal, formaldehyde, acetaldehyde, and benzaldehyde. The aldehyde is preferably propionaldehyde, n-butanal, isobutanal, n-hexanal or n-pentanal, more preferably propionaldehyde, n-butanal or isobutanal, still more preferably n-butanal. The aldehyde may be used alone or in combination of two or more.

[0087] The content rate (amount of hydroxyl groups) of the hydroxyl groups in the polyvinyl acetal resin is preferably 15 mol% or more, more preferably 18 mol% or more, still more preferably 20 mol% or more, particularly preferably 28 mol% or more, preferably 40 mol% or less, more preferably 35 mol% or less, still more preferably 32 mol% or less. When the content rate of the hydroxyl groups is at least the lower limit, the adhesive force of the resin layer is further improved. In addition, when the content rate of the hydroxyl groups is at most the upper limit, the flexibility of the resin layer is increased and the treatment of the resin layer becomes easier.

[0088] The content rate of the hydroxyl groups in the polyvinyl acetal resin is a value expressed as a percentage of the mole fraction obtained by dividing the amount of ethylene groups bonded with hydroxyl groups by the total amount of ethylene groups in the main chain. The amount of ethylene groups bonded with hydroxyl groups can be measured, for example, according to JIS K6728 "Test Method for Polyvinyl Butyral".

[0089] The acetylation degree (acetyl group content) of the polyvinyl acetal resin is preferably 0.1 mol% or more, more preferably 0.3 mol% or more, further preferably 0.5 mol% or more, preferably 30 mol% or less, more preferably 25 mol% or less, further preferably 20 mol% or less, particularly preferably 15 mol% or less, and most preferably 3 mol% or less. When the acetylation degree is at least the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer becomes higher. When the acetylation degree is at most the upper limit, the moisture resistance of the laminated glass becomes higher.

[0090] The acetylation degree is the value expressed as a percentage of the mole fraction obtained by dividing the amount of ethylene groups bonded with acetyl groups by the total amount of ethylene groups in the main chain. The amount of ethylene groups bonded with acetyl groups can be measured, for example, in accordance with JIS K6728 "Test Methods for Polyvinyl Butyral".

[0091] The acetalization degree (butyralization degree in the case of polyvinyl butyral resin) of the polyvinyl acetal resin is preferably 60 mol% or more, more preferably 63 mol% or more, preferably 85 mol% or less, more preferably 75 mol% or less, and further preferably 70 mol% or less. When the acetalization degree is at least the lower limit, the compatibility of the polyvinyl acetal resin with the plasticizer becomes higher. When the acetalization degree is at most the upper limit, the reaction time required for manufacturing the polyvinyl acetal resin becomes shorter.

[0092] The acetalization degree is determined as follows. First, the value obtained by subtracting the amount of ethylene groups bonded with hydroxyl groups and the amount of ethylene groups bonded with acetyl groups from the total amount of ethylene groups in the main chain is obtained. The mole fraction is obtained by dividing the obtained value by the total amount of ethylene groups in the main chain. The value of the mole fraction expressed as a percentage is the acetalization degree.

[0093] It should be noted that the hydroxyl group content (hydroxyl amount), acetalization degree (butyralization degree), and acetylation degree are preferably calculated from the results measured by the method in accordance with JIS K6728 "Test Methods for Polyvinyl Butyral". Among them, the measurement based on ASTM D1396 - 92 can also be used. In the case where the polyvinyl acetal resin is a polyvinyl butyral resin, the hydroxyl group content (hydroxyl amount), the acetalization degree (butyralization degree), and the acetylation degree can be calculated from the results measured by the method in accordance with JIS K6728 "Test Methods for Polyvinyl Butyral".

[0094] In 100% by weight of the thermoplastic resin contained in the first resin layer, the content of the polyvinyl acetal resin is preferably 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more, further preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more. In 100% by weight of the thermoplastic resin contained in the first resin layer, the content of the polyvinyl acetal resin is preferably 100% by weight or less. The main component (50% by weight or more) of the thermoplastic resin in the first resin layer is preferably a polyvinyl acetal resin.

[0095] In 100% by weight of the thermoplastic resin contained in the second resin layer, the content of the polyvinyl acetal resin is preferably 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more, further preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more. In 100% by weight of the thermoplastic resin contained in the second resin layer, the content of the polyvinyl acetal resin 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 a polyvinyl acetal resin.

[0096] <Plasticizer>

[0097] From the viewpoint of further improving the adhesive force of the resin layer, the first resin layer preferably contains a plasticizer (hereinafter, sometimes referred to as plasticizer (1)). From the viewpoint of further improving the adhesive force of the resin layer, the second resin layer preferably contains a plasticizer (hereinafter, sometimes referred to as plasticizer (2)). When the thermoplastic resin contained in the resin layer is a polyvinyl acetal resin, it is particularly preferred that the resin layer contains a plasticizer. The layer containing a polyvinyl acetal resin preferably contains a plasticizer.

[0098] In the following description, for the common constitution of the plasticizer (1) and the plasticizer (2), it will be described only as "plasticizer".

[0099] The plasticizer is not particularly limited. As the plasticizer, known plasticizers can be used. The plasticizer may be used alone or in combination of two or more.

[0100] Examples of the plasticizer include organic ester plasticizers such as monobasic organic acid esters and polybasic organic acid esters, and organic phosphoric acid plasticizers and organic phosphorous acid plasticizers. The plasticizer is preferably an organic ester plasticizer. The plasticizer is preferably a liquid plasticizer.

[0101] Examples of the monobasic organic acid ester include glycol esters obtained by the reaction of a 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, heptanoic acid, n-octanoic acid, 2-ethylhexanoic acid, n-nonanoic acid, decanoic acid, and benzoic acid.

[0102] Examples of the polybasic organic acid ester include ester compounds of a polybasic organic acid and an alcohol having a linear or branched structure with 4 to 8 carbon atoms. Examples of the polybasic organic acid include adipic acid, sebacic acid, and azelaic acid.

[0103] Examples of the organic ester plasticizer include triethylene glycol di-2-ethylpropionate, triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol dioctanoate, 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-propanediol di-2-ethylbutyrate, 1,4-butanediol di-2-ethylbutyrate, diethylene glycol di-2-ethylbutyrate, diethylene glycol di-2-ethylhexanoate, dipropylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylvalerate, tetraethylene glycol di-2-ethylbutyrate, diethylene glycol dioctanoate, diethylene glycol dibenzoate, dipropylene glycol dibenzoate, dihexyl adipate, dioctyl adipate, hexyl cyclohexyl adipate, a mixture of adipic acid heptyl and adipic acid nonyl esters, diisononyl adipate, diisodecyl adipate, heptyl nonyl adipate, dibutyl sebacate, oil-modified sebacic acid alkyd, and a mixture of a phosphate ester and an adipic acid ester. As the organic ester plasticizer, organic ester plasticizers other than these can be used. In addition, as the adipic acid ester, other adipic acid esters other than the above-mentioned adipic acid esters can be used.

[0104] Examples of the organic phosphoric acid plasticizer include tributoxyethyl phosphate, isodecyl phenyl phosphate, and triisopropyl phosphate.

[0105] The plasticizer is preferably a diester plasticizer represented by the following formula (1).

[0106] [Chemical formula 1]

[0107]

[0108] In the formula (1), R1 and R2 each represent an organic group having 2 to 10 carbon atoms, R3 represents an ethylene group, an isopropylidene group, or a n-propylene group, and p represents an integer of 3 to 10. R1 and R2 in the formula (1) are each preferably an organic group having 5 to 10 carbon atoms, more preferably an organic group having 6 to 10 carbon atoms.

[0109] The plasticizer preferably contains triethylene glycol bis(2-ethylhexanoate) (3GO), triethylene glycol bis(2-ethylbutyrate) (3GH), or triethylene glycol bis(2-ethylpropionate). The plasticizer more preferably contains triethylene glycol bis(2-ethylhexanoate) (3GO) or triethylene glycol bis(2-ethylbutyrate) (3GH), and still more preferably contains triethylene glycol bis(2-ethylhexanoate) (3GO).

[0110] Based on 100 parts by weight of the thermoplastic resin (1) contained in the first resin layer, the content of the plasticizer (1) contained in the first resin layer is defined as content (1). Content (1) is preferably 25 parts by weight or more, more preferably 30 parts by weight or more, still more preferably 35 parts by weight or more, preferably 75 parts by weight or less, more preferably 60 parts by weight or less, still more preferably 50 parts by weight or less, and particularly preferably 40 parts by weight or less. When content (1) is at or above the lower limit, the penetration resistance of the laminated glass is further improved. When content (1) is at or below the upper limit, the transparency of the laminated glass is further improved.

[0111] Based on 100 parts by weight of the thermoplastic resin (2) contained in the second resin layer, the content of the plasticizer (2) contained in the second resin layer is defined as content (2). Content (2) is preferably 25 parts by weight or more, more preferably 30 parts by weight or more, still more preferably 35 parts by weight or more, preferably 75 parts by weight or less, more preferably 60 parts by weight or less, still more preferably 50 parts by weight or less, and particularly preferably 40 parts by weight or less. When content (2) is at or above the lower limit, the penetration resistance of the laminated glass is further improved. When content (2) is at or below the upper limit, the transparency of the laminated glass is further improved.

[0112] <Heat-insulating substance>

[0113] The interlayer preferably contains a heat-insulating substance. The first resin layer preferably contains a heat-insulating substance. The first resin layer may also not contain a heat-insulating substance. The second resin layer preferably contains a heat-insulating substance. The second resin layer may also not contain a heat-insulating substance. Only one type of the heat-insulating substance may be used, or two or more types may be used in combination.

[0114] The heat-insulating substance preferably contains at least one component X selected from phthalocyanine compounds, naphthalocyanine compounds, and anthracene phthalocyanine compounds, or contains heat-insulating particles. In this case, the heat-insulating substance may contain both the component X and the heat-insulating particles.

[0115] Component X:

[0116] The intermediate film preferably contains at least one component X selected from phthalocyanine compounds, naphthalocyanine compounds, and anthracene phthalocyanine compounds. The first resin layer preferably contains the component X. The second resin layer preferably contains the component X. Only one kind of the component X can be used, or two or more kinds can be used in combination.

[0117] The component X is not particularly limited. As the component X, known phthalocyanine compounds, naphthalocyanine compounds, and anthracene phthalocyanine compounds can be used.

[0118] Examples of the component X include phthalocyanine, derivatives of phthalocyanine, naphthalocyanine, derivatives of naphthalocyanine, anthracene phthalocyanine, and derivatives of anthracene phthalocyanine. The phthalocyanine compound and the derivative of phthalocyanine preferably have a phthalocyanine skeleton respectively. The naphthalocyanine compound and the derivative of naphthalocyanine preferably have a naphthalocyanine skeleton respectively. The anthracene phthalocyanine compound and the derivative of anthracene phthalocyanine preferably have an anthracene phthalocyanine skeleton respectively.

[0119] From the viewpoint of further improving the heat insulation of the intermediate film and the laminated glass, the component X is preferably at least one selected from phthalocyanine, derivatives of phthalocyanine, naphthalocyanine, and derivatives of naphthalocyanine, and more preferably at least one of phthalocyanine and derivatives of phthalocyanine.

[0120] From the viewpoints of effectively improving the heat insulation and maintaining the visible light transmittance at a higher level for a long 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 phthalocyanine containing a vanadium atom or a copper atom and derivatives of phthalocyanine containing a vanadium atom or a copper atom. From the viewpoint of further improving the heat insulation of the intermediate film and the laminated glass, the component X preferably has a structural unit in which an oxygen atom is bonded to the vanadium atom.

[0121] In 100% by weight of the layer (the first resin layer or the second resin layer) containing the component X, the content of the component X is preferably 0.0005% by weight or more, more preferably 0.005% by weight or more, further preferably 0.01% by weight or more, particularly preferably 0.02% by weight or more, preferably 0.2% by weight or less, more preferably 0.1% by weight or less, further preferably 0.05% by weight or less, and particularly preferably 0.04% by weight or less. If the content of the component X is above the lower limit and below the upper limit, the heat insulation is sufficiently increased and the visible light transmittance is sufficiently increased. For example, the visible light transmittance can be 70% or more.

[0122] Heat insulation particles:

[0123] The intermediate film preferably contains heat insulating particles. The first resin layer preferably contains the heat insulating particles. The second resin layer preferably contains the heat insulating particles. The heat insulating particles are heat insulating substances. By using the heat insulating particles, infrared rays (heat rays) can be effectively blocked. One type of heat insulating particle may be used alone, or two or more types may be used in combination.

[0124] From the viewpoint of further improving the heat insulation of the laminated glass, the heat insulating particles are more preferably metal oxide particles. The heat insulating particles are preferably particles formed of an oxide of a metal (metal oxide particles).

[0125] Infrared rays with a wavelength of 780 nm or more, which is longer than visible light, have a smaller amount of energy compared to ultraviolet rays. However, the thermal effect of infrared rays is large, and when infrared rays are absorbed by a substance, they are released as heat. Therefore, infrared rays are generally called heat rays. By using the heat insulating particles, infrared rays (heat rays) can be effectively blocked. It should be noted that heat insulating particles are particles that can absorb infrared rays.

[0126] Specific examples of the heat insulating particles include 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, tungsten oxide particles (sodium-doped tungsten oxide particles, cesium-doped tungsten oxide particles, thallium-doped tungsten oxide particles, rubidium-doped tungsten oxide particles, etc.), tin-doped indium oxide particles (ITO particles), tin-doped zinc oxide particles, silicon-doped zinc oxide particles, and other metal oxide particles, lanthanum hexaboride (LaB6) particles, etc. Heat insulating particles other than these may also be used. Since the heat ray shielding function is high, metal oxide particles are preferred, and ATO particles, GZO particles, IZO particles, ITO particles, or tungsten oxide particles are more preferred, and ITO particles or tungsten oxide particles are particularly preferred. In particular, since the heat ray shielding function is high and it is easily obtained, tin-doped indium oxide particles (ITO particles) are preferred, and tungsten oxide particles are also preferred.

[0127] From the viewpoint of further improving the heat insulation of the intermediate film and the 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.

[0128] From the viewpoint of further improving the heat insulation of the intermediate film and the laminated glass, cesium-doped tungsten oxide particles are particularly preferred. From the viewpoint of further improving the heat insulation of the intermediate film and the laminated glass, the cesium-doped tungsten oxide particles preferably have the formula: Cs 0.33Tungsten oxide particles shown in WO3.

[0129] The average particle size of the heat-insulating particles is preferably 0.01 μm or more, more preferably 0.02 μm or more, preferably 0.1 μm or less, and more preferably 0.05 μm or less. If the average particle size is above the lower limit, the shielding property of the hot wire becomes sufficiently high. When the average particle size is below the upper limit, the dispersibility of the heat-insulating particles becomes high.

[0130] The "average particle size" represents the volume average particle size. The average particle size can be measured using a particle size distribution measuring device (such as "UPA-EX150" manufactured by Nikkiso Co., Ltd.).

[0131] In 100% by weight of the layer (the first resin layer or the second resin layer) containing the heat-insulating particles, the content of the heat-insulating particles (especially the content of tungsten oxide particles) is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, further preferably 1% by weight or more, particularly preferably 1.5% by weight or more, preferably 6% by weight or less, more preferably 5.5% by weight or less, further preferably 4% by weight or less, particularly preferably 3.5% by weight or less, and most preferably 3% by weight or less. If the content of the heat-insulating particles is above the lower limit and below the upper limit, the heat insulation property becomes sufficiently high, and the visible light transmittance becomes sufficiently high.

[0132] <Metal salt>

[0133] The interlayer film preferably contains at least one metal salt selected from alkali metal salts and alkaline earth metal salts (hereinafter, sometimes referred to as metal salt M). The first resin layer preferably contains the metal salt M. The second resin layer preferably contains the metal salt M. It should be noted that alkaline earth metals refer to 6 metals: Be, Mg, Ca, Sr, Ba, and Ra. By using the metal salt M, it is easy to control the adhesiveness between the interlayer film and a laminated glass component such as a glass plate or the adhesiveness between the layers in the interlayer film. The metal salt M can be used alone or in combination of two or more.

[0134] The metal salt M preferably contains at least one metal selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba. The metal salt M contained in the interlayer film more preferably contains at least one metal selected from K and Mg.

[0135] In addition, as the metal salt M, alkali metal salts of organic acids having 2 to 16 carbon atoms and alkaline earth metal salts of organic acids having 2 to 16 carbon atoms can be used. The metal salt M can contain magnesium carboxylate salts having 2 to 16 carbon atoms or potassium carboxylate salts having 2 to 16 carbon atoms.

[0136] Examples of the magnesium carboxylate salt having 2 to 16 carbon atoms and the potassium carboxylate salt having 2 to 16 carbon atoms include magnesium acetate, potassium acetate, magnesium propionate, potassium propionate, magnesium 2-ethylbutyrate, potassium 2-ethylbutyrate, magnesium 2-ethylhexanoate, and potassium 2-ethylhexanoate.

[0137] The total content of Mg and K in the layer containing the metal salt M (the first resin layer or the second resin layer) is preferably 5 ppm or more, more preferably 10 ppm or more, still more preferably 20 ppm or more, preferably 300 ppm or less, more preferably 250 ppm or less, and still more preferably 200 ppm or less. When the total content of Mg and K is within the above lower limit and upper limit, the adhesiveness between the interlayer film and the laminated glass member (such as a glass plate) or the adhesiveness between the layers in the interlayer film can be further better controlled.

[0138] <Ultraviolet ray shielding agent>

[0139] The interlayer film preferably contains an ultraviolet ray shielding agent. The first resin layer preferably contains an ultraviolet ray shielding agent. The second resin layer preferably contains an ultraviolet ray shielding agent. By using an ultraviolet ray shielding agent, the visible light transmittance is less likely to decrease even when the laminated glass is used for a long time. Only one kind of ultraviolet ray shielding agent may be used, or two or more kinds may be used in combination.

[0140] The ultraviolet ray shielding agent contains an ultraviolet absorber. The ultraviolet ray shielding agent is preferably an ultraviolet absorber.

[0141] Examples of the ultraviolet ray shielding agent include an ultraviolet ray shielding agent containing a metal atom, an ultraviolet ray shielding agent containing a metal oxide, an ultraviolet ray shielding agent having a benzotriazole structure (benzotriazole compound), an ultraviolet ray shielding agent having a benzophenone structure (benzophenone compound), an ultraviolet ray shielding agent having a triazine structure (triazine compound), an ultraviolet ray shielding agent having a malonate structure (malonate compound), an ultraviolet ray shielding agent having an oxanilide structure (oxanilide compound), and an ultraviolet ray shielding agent having a benzoate structure (benzoate compound).

[0142] Examples of the ultraviolet ray shielding agent containing a metal atom include platinum particles, particles obtained by coating the surface of platinum particles with silica, palladium particles, and particles obtained by coating the surface of palladium particles with silica. The ultraviolet ray shielding agent is preferably not heat-insulating particles.

[0143] The ultraviolet light screening agent is preferably an ultraviolet light screening agent having a benzotriazole structure, an ultraviolet light screening agent having a benzophenone structure, an ultraviolet light screening agent having a triazine structure, or an ultraviolet light screening agent having a benzoate structure. The ultraviolet light screening agent is more preferably an ultraviolet light screening agent having a benzotriazole structure or an ultraviolet light screening agent having a benzophenone structure, and further preferably an ultraviolet light screening agent having a benzotriazole structure.

[0144] Examples of the ultraviolet light screening agent containing the metal oxide include zinc oxide, titanium oxide, cerium oxide, etc. In addition, the surface of the ultraviolet light screening agent containing the metal oxide can also be coated. Examples of the coating material for the surface of the ultraviolet light screening agent containing the metal oxide include insulating metal oxides, hydrolyzable organosilicon compounds, and polysiloxane compounds.

[0145] Examples of the insulating metal oxide include silicon dioxide, aluminum oxide, zirconium oxide, etc. The insulating metal oxide has a band gap energy of 5.0 eV or more, for example.

[0146] Examples of the ultraviolet light screening agent having a benzotriazole structure include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole ("Tinuvin P" manufactured by BASF), 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole ("Tinuvin 320" manufactured by BASF), 2-(2'-hydroxy-3'-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole ("Tinuvin 326" manufactured by BASF), and 2-(2'-hydroxy-3',5'-dipentylphenyl)benzotriazole ("Tinuvin 328" manufactured by BASF). From the aspect of excellent ultraviolet light screening performance, the ultraviolet light screening agent is preferably an ultraviolet light screening agent having a benzotriazole structure containing a halogen atom, and more preferably an ultraviolet light screening agent having a benzotriazole structure containing a chlorine atom.

[0147] Examples of the ultraviolet light screening agent having a benzophenone structure include Octabenzone ("Chimassorb 81" manufactured by BASF).

[0148] Examples of the ultraviolet light screening agent having a triazine structure include "LA-F70" manufactured by ADEKA and 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol ("Tinuvin 1577FF" manufactured by BASF).

[0149] Examples of the ultraviolet light screening agent having a malonate structure include dimethyl 2-(p-methoxybenzylidene)malonate, tetraethyl 2,2-(1,4-phenylenedimethylene)bis(malonate), 2-(p-methoxybenzylidene)-bis(1,2,2,6,6-pentamethyl-4-piperidyl)malonate, and the like.

[0150] Examples of commercially available products of the ultraviolet light screening agent having a malonate structure include Hostavin B-CAP, Hostavin PR-25, and Hostavin PR-31 (all manufactured by Clariant).

[0151] Examples of the ultraviolet light screening agent having an oxanilide structure include oxalic acid diamides such as N-(2-ethylphenyl)-N'-(2-ethoxy-5-tert-butylphenyl)oxamide, N-(2-ethylphenyl)-N'-(2-ethoxyphenyl)oxamide, and 2-ethyl-2'-ethoxy-oxanilide ("Sanduvor VSU" manufactured by Clariant), which have an aryl group substituted on the nitrogen atom.

[0152] Examples of the ultraviolet light screening agent having a benzoate structure include 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate ("Tinuvin 120" manufactured by BASF), and the like.

[0153] In 100% by weight of the layer (the first resin layer or the second resin layer) containing the ultraviolet light screening agent, the content of the ultraviolet light screening agent is preferably 0.1% by weight or more, more preferably 0.2% by weight or more, further preferably 0.3% by weight or more, particularly preferably 0.5% by weight or more, preferably 2.5% by weight or less, more preferably 2% by weight or less, further preferably 1% by weight or less, and particularly preferably 0.8% by weight or less. If the content of the ultraviolet light screening agent is at or above the lower limit, the decrease in visible light transmittance after the passage of time can be further suppressed. When the content of the ultraviolet light screening agent is at or below the upper limit, the decrease in visible light transmittance after the passage of time of the intermediate film and the laminated glass can be significantly suppressed.

[0154] <Antioxidant>

[0155] The intermediate film preferably contains an antioxidant. The first resin layer preferably contains an antioxidant. The second resin layer preferably contains an antioxidant. Only one kind of antioxidant can be used, or two or more kinds can be used in combination.

[0156] Examples of the antioxidant include phenolic antioxidants, sulfur antioxidants, and phosphorus antioxidants. The phenolic antioxidant is an antioxidant having a phenol skeleton. The sulfur antioxidant is an antioxidant containing a sulfur atom. The phosphorus antioxidant is an antioxidant containing a phosphorus atom.

[0157] The antioxidant is preferably a phenolic antioxidant or a phosphorus antioxidant.

[0158] Examples of the phenolic antioxidant include 2,6-di-tert-butyl-p-cresol (BHT), butylated hydroxyanisole (BHA), 2,6-di-tert-butyl-4-ethylphenol, stearyl β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2,2'-methylenebis-(4-methyl-6-butylphenol), 2,2'-methylenebis-(4-ethyl-6-tert-butylphenol), 4,4'-butylidene-bis-(3-methyl-6-tert-butylphenol), 1,1,3-tris-(2-methyl-hydroxy-5-tert-butylphenyl) butane, tetra[methylene-3-(3',5'-tert-butyl-4-hydroxyphenyl) propionate] methane, 1,3,3-tris-(2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl) benzene, bis(3,3'-tert-butylphenol) butanediol ester, and bis(3-tert-butyl-4-hydroxy-5-methylphenylpropionic acid) ethylidene bis(oxyethylene), etc. It is preferred to use one or more of these antioxidants.

[0159] Examples of the phosphorus antioxidant include tridecyl phosphite, tris(tridecyl) phosphite, triphenyl phosphite, tris(nonylphenyl) phosphite, bis(tridecyl)pentaerythritol diphosphite, bis(decyl)pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, bis(2,4-di-tert-butyl-6-methylphenyl) ethyl phosphite, and 2,2'-methylenebis(4,6-di-tert-butyl-1-phenoxy)(2-ethylhexoxy) phosphorus, etc. It is preferred to use one or more of these antioxidants.

[0160] Examples of commercially available products of the antioxidant include "IRGANOX 245" manufactured by BASF, "IRGAFOS 168" manufactured by BASF, "IRGAFOS 38" manufactured by BASF, "SUMILIZER BHT" manufactured by Sumitomo Chemical Industry Co., Ltd., "H-BHT" manufactured by SAKAI CHEMICAL INDUSTRY Co., Ltd., and "IRGANOX 1010" manufactured by BASF, etc.

[0161] In order to maintain a high visible light transmittance of the interlayer film and laminated glass for a long time, in 100% by weight of the layer containing the antioxidant (the first resin layer or the second resin layer), the content of the antioxidant is preferably 0.03% by weight or more, more preferably 0.1% by weight or more. In addition, from the viewpoint of saturation of the addition effect of the antioxidant, in 100% by weight of the layer containing the antioxidant (the first resin layer or the second resin layer), the content of the antioxidant is preferably 2% by weight or less.

[0162] <Other components>

[0163] The first resin layer and the second resin layer may each contain additives such as a light stabilizer, a coupling agent, a dispersant, a surfactant, a flame retardant, an antistatic agent, a pigment, a dye, an adhesion regulator other than a metal salt, a moisture-resistant agent, a fluorescent brightening agent, and an infrared absorber as needed. Each of the other components may be used alone or in combination of two or more.

[0164] (Other details of the interlayer film for laminated glass)

[0165] The thickness of the interlayer film is not particularly limited. From the viewpoints of practicality and sufficiently improving the penetration resistance and bending rigidity of the laminated glass, the thickness of the interlayer film is preferably 0.1 mm or more, more preferably 0.25 mm or more, preferably 3 mm or less, and more preferably 1.5 mm or less. When the thickness is above the lower limit, the penetration resistance and bending rigidity of the laminated glass are further improved. When the thickness is below the upper limit, the transparency of the interlayer film becomes better.

[0166] The interlayer film may be an interlayer film with a uniform thickness or an interlayer film with a variable thickness. The cross-sectional shape of the interlayer film may be rectangular or wedge-shaped. It should be noted that in the case where the cross-sectional shape of the interlayer film is wedge-shaped (the case of an interlayer film with a variable thickness), the thickness of the interlayer film refers to the average thickness.

[0167] As the manufacturing method of the interlayer film, for example, the methods described in the following manufacturing method (1) and the following manufacturing method (2) can be cited. The manufacturing method of the interlayer film is preferably the following manufacturing method (1) or the following manufacturing method (2).

[0168] The manufacturing method (1) of the intermediate film comprises: a step of obtaining a laminate which sequentially comprises: a first resin layer forming layer containing a thermoplastic resin, a polyethylene terephthalate film; and a second resin layer forming layer containing a thermoplastic resin. The manufacturing method (1) of the intermediate film comprises: a step of curing the laminate such that in the obtained intermediate film, the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm (absorbance A / absorbance B) is 0.50 or less.

[0169] The step of curing the laminate is preferably carried out before the intermediate film is disposed between the first laminated glass component and the second laminated glass component.

[0170] The manufacturing method (2) of the intermediate film comprises: a step of curing at least one of the first resin layer forming layer containing a thermoplastic resin and the second resin layer forming layer containing a thermoplastic resin such that in the obtained intermediate film, the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm (absorbance A / absorbance B) is 0.50 or less. This step can be a step of curing the first resin layer forming layer, a step of curing the second resin layer forming layer, or a step of curing the first resin layer forming layer and the second resin layer forming layer respectively.

[0171] In the manufacturing method (2) of the intermediate film, preferably, after the step of curing, it comprises: a step of obtaining a laminate which sequentially comprises: a first resin layer forming layer containing a thermoplastic resin, a polyethylene terephthalate film; and a second resin layer forming layer containing a thermoplastic resin.

[0172] In the step of obtaining the laminate in the manufacturing methods (1) and (2) of the intermediate film, the method of obtaining the laminate is not particularly limited. For example, a method of sequentially laminating the first resin layer forming layer, the polyethylene terephthalate film, and the second resin layer forming layer can be cited.

[0173] The curing step in the manufacturing methods (1) and (2) of the intermediate film is preferably a step (A) of maintaining for 6 hours or more in an environment with a curing temperature of 20°C or higher and 30°C or lower and a curing humidity of 10%RH or higher and 40%RH or lower, or a step (B) of maintaining for 8 minutes or less in an environment with a curing temperature of 40°C or higher and 60°C or lower and a curing humidity of 85%RH or higher and 99%RH or lower. In this case, it is easy to adjust the ratio (absorbance A / absorbance B) to 0.50 or less. Especially when the curing temperature is 20°C or higher and 30°C or lower, in order to adjust the ratio (absorbance A / absorbance B) to 0.50 or less, it is necessary to maintain the curing humidity during curing quite low.

[0174] From the viewpoint of more easily controlling the ratio (absorbance A / absorbance B), the curing temperature, curing humidity, and curing time in the step (A) and the step (B) preferably satisfy the following conditions respectively.

[0175] The curing temperature in the step (A) is preferably 22°C or higher, more preferably 23°C or higher, preferably 28°C or lower, more preferably 27°C or lower. The curing humidity in the step (A) is preferably 15%RH or higher, more preferably 20%RH or higher, preferably 35%RH or lower, more preferably 30%RH or lower. The curing time in the step (A) is preferably 7 hours or more, more preferably 8 hours or more. The upper limit of the curing time in the step (A) is not particularly limited. The curing time in the step (A) is, for example, 24 hours or less.

[0176] The curing temperature in the step (B) is preferably 43°C or higher, more preferably 45°C or higher, preferably 58°C or lower, more preferably 55°C or lower. The curing humidity in the step (B) is preferably 90%RH or higher, more preferably 93%RH or higher, preferably 98%RH or lower, more preferably 97%RH or lower. The curing time in the step (B) is preferably 7 minutes or less, more preferably 6 minutes or less. The lower limit of the curing time in the step (B) is not particularly limited. The curing time in the step (B) is, for example, 0.5 minutes or more.

[0177] (Laminated glass)

[0178] The laminated glass of the present invention includes a first laminated glass component, a second laminated glass component, and an intermediate film. In the laminated glass of the present invention, the intermediate film is disposed between the first laminated glass component and the second laminated glass component.

[0179] Figure 3 It schematically shows Figure 2 a cross-sectional view of an example of a laminated glass using the intermediate film for laminated glass shown.

[0180] Figure 3 The laminated glass 31 shown includes a first laminated glass component 21, a second laminated glass component 22, and an interlayer film 11. The interlayer film 11 is disposed and sandwiched between the first laminated glass component 21 and the second laminated glass component 22.

[0181] The first laminated glass component 21 is laminated on the first surface 11a of the interlayer film 11. The second laminated glass component 22 is laminated on the second surface 11b of the interlayer film 11 opposite to the first surface 11a. The first laminated glass component 21 is disposed and laminated on the outer surface 2a of the first resin layer 2. The second laminated glass component 22 is disposed and laminated on the outer surface 3a of the second resin layer 3.

[0182] Examples of the first and second laminated glass components 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 it is preferable to use at least one glass plate. It is preferable that the first laminated glass component and the second laminated glass component are each a glass plate or a PET film, and the laminated glass includes a glass plate as at least one of the first laminated glass component and the second laminated glass component. It is particularly preferable that both the first and second laminated glass components are glass plates.

[0183] Examples of the glass plate include inorganic glass and organic glass. Examples of the inorganic glass include float plate glass, hot wire absorption plate glass, hot wire reflection plate glass, polished plate glass, shaped plate glass, wired glass, and green glass. The organic glass is 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 plate include poly(methyl methacrylate) plates.

[0184] The first laminated glass component is preferably a first glass plate. The second laminated glass component is preferably a second glass plate.

[0185] The thicknesses of the first and second laminated glass components are preferably 1 mm or more, more preferably 1.8 mm or more, further preferably 2 mm or more, particularly preferably 2.1 mm or more, and preferably 5 mm or less, more preferably 3 mm or less. In addition, when the first and second laminated glass components are glass plates, the thickness of the glass plate is preferably 1 mm or more, more preferably 1.8 mm or more, further preferably 2 mm or more, particularly preferably 2.1 mm or more, preferably 5 mm or less, more preferably 3 mm or less, and further preferably 2.6 mm or less. When the first and second laminated glass components are PET films, the thickness of the PET film is preferably 0.03 mm or more and preferably 0.5 mm or less.

[0186] The manufacturing method of the laminated glass is not particularly limited. First, an interlayer film is sandwiched between the first laminated glass component and the second laminated glass component to obtain a laminate. Then, for example, the obtained laminate is passed through a pressing roller or placed in a rubber bag for reduced-pressure suction, thereby degassing the air remaining between the first laminated glass component, the second laminated glass component, and the interlayer film. Then, pre-bonding is performed at about 70 to 110 °C to obtain a pre-pressed laminate. Next, the pre-pressed laminate is placed in an autoclave or pressed, and press-bonding is performed at a pressure of about 120 to 150 °C and 1 to 1.5 MPa. In this way, laminated glass can be obtained. When manufacturing the laminated glass, each layer can be laminated.

[0187] The interlayer film and the laminated glass can be used for automobiles, railway vehicles, airplanes, ships, buildings, etc. The interlayer film and the laminated glass can also be used for purposes other than these. The interlayer film and the laminated glass are preferably interlayer films and laminated glasses for vehicles or buildings, more preferably interlayer films and laminated glasses for vehicles. The interlayer film and the laminated glass can be used for the front glass, side glass, rear glass, roof glass, or backlight glass of an automobile, etc. The interlayer film and the laminated glass are suitable for use in automobiles. The interlayer film is suitable for obtaining the laminated glass of an automobile.

[0188] Hereinafter, examples and comparative examples will be given to specifically illustrate the present invention. The present invention is not limited to the following examples.

[0189] In the polyvinyl butyral resin used, n-butyraldehyde having 4 carbon atoms is used for acetalization. Regarding the polyvinyl butyral resin, the degree of acetalization (degree of butyral acetalization), the degree of acetylation, and the hydroxyl group content are measured by the method according to JIS K6728 "Test Method for Polyvinyl Butyral". It should be noted that when measured by ASTM D1396-92, the same values as those measured by the method according to JIS K6728 "Test Method for Polyvinyl Butyral" are also shown.

[0190] (Thermoplastic resin)

[0191] Polyvinyl butyral resin (PVB, average degree of polymerization 1700, hydroxyl group content 30.5 mol%, acetylation degree 1 mol%, acetalization degree 68.5 mol%)

[0192] (Plasticizer)

[0193] 3GO: Triethylene glycol di-2-ethylhexanoate

[0194] (Metal salt)

[0195] Mg mixture (50:50 (weight ratio) mixture of magnesium 2-ethylbutyrate and magnesium acetate)

[0196] (UV screening agent)

[0197] Tinuvin326: 2-(2'-hydroxy-3'-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole ("Tinuvin326" manufactured by BASF)

[0198] (Antioxidant)

[0199] BHT: 2,6-Di-tert-butyl-p-cresol

[0200] Prepare the following polyethylene terephthalate films.

[0201] Nano90S (Multilayer polyethylene terephthalate film, "MULTILAYER Nano 90S" manufactured by Sumitomo 3M Limited, thickness 75 μm)

[0202] XIR-75 (Polyethylene terephthalate film containing a metal layer, "XIR-75" manufactured by Southwall Technologies, thickness 50 μm)

[0203] LUMIRROR T60 (Single-layer polyethylene terephthalate film, "LUMIRROR T60" manufactured by TORAY, thickness 100 μm)

[0204] ST-22 (Multilayer polyethylene terephthalate film, "ST-22" manufactured by TORAY, thickness 100 μm)

[0205] In addition, the curing conditions below are as shown in Table 1 below.

[0206] [Table 1]

[0207]

[0208] (Example 1)

[0209] Preparation of the layer for forming the first resin layer:

[0210] The following components are formulated and thoroughly kneaded with a mixing roll to obtain a composition for forming the first resin layer.

[0211] PVB: 100 parts by weight

[0212] 3GO: 40 parts by weight

[0213] Mg mixture: an amount such that the magnesium content in the obtained first resin layer becomes 70 ppm

[0214] Tinuvin326: an amount such that it becomes 0.2% by weight in the obtained first resin layer

[0215] BHT: an amount such that it becomes 0.2% by weight in the obtained first resin layer

[0216] The obtained composition for forming the first resin layer is extruded using an extruder to obtain the layer for forming the first resin layer.

[0217] Preparation of the layer for forming the second resin layer:

[0218] The following components are formulated and thoroughly kneaded with a mixing roll to obtain a composition for forming the second resin layer.

[0219] PVB: 100 parts by weight

[0220] 3GO: 40 parts by weight

[0221] Mg mixture: an amount such that the magnesium content in the obtained second resin layer becomes 70 ppm

[0222] Tinuvin326: an amount such that it becomes 0.2% by weight in the obtained second resin layer

[0223] BHT: an amount such that it becomes 0.2% by weight in the obtained second resin layer

[0224] The obtained composition for forming the second resin layer is extruded using an extruder to obtain the layer for forming the second resin layer.

[0225] The obtained layer for forming the first resin layer and the layer for forming the second resin layer are respectively cured under the curing conditions A described in Table 1.

[0226] Next, the layer for forming the first resin layer, the polyethylene terephthalate film described in Table 2, and the layer for forming the second resin layer are sequentially laminated, and pressed under the conditions of 100 °C and 0.2 MPa using a pressing roll to obtain an intermediate film. In the obtained intermediate film, the first resin layer and the second resin layer are respectively rectangular, and in addition, the thicknesses of the first resin layer and the second resin layer are 380 μm respectively.

[0227] Preparation of laminated glass:

[0228] Prepare two pieces of transparent glass with a thickness of 2 mm according to JIS R3202:1996. Sandwich the obtained intermediate film between the two pieces of transparent glass to obtain a laminate. Put the obtained laminate into a rubber bag, degas it for 20 minutes under a vacuum of 2.6 kPa, then transfer it to an oven in the degassed state, and then keep it at 90 °C for 30 minutes for vacuum pressing to pre-bond the laminate. In an autoclave, press the pre-bonded laminate at 135 °C and a pressure of 1.2 MPa for 20 minutes to obtain laminated glass (10 cm in length × 10 cm in width). It should be noted that the obtained laminated glass corresponds to the laminated glass X.

[0229] (Examples 2 to 8 and Comparative Examples 1 to 6)

[0230] Change the type of polyethylene terephthalate film and the curing conditions as recorded in the following table, and obtain an intermediate film and laminated glass (laminated glass X) in the same manner as in Example 1.

[0231] (Reference Examples A to F)

[0232] Do not use the polyethylene terephthalate film and change the curing conditions as recorded in the following table, and obtain an intermediate film and laminated glass (laminated glass X) in the same manner as in Example 1.

[0233] (Evaluation)

[0234] (1) Absorbance

[0235] In the obtained laminated glass (laminated glass X), take the position 3 cm from one end to the other end as the first position, and the position 5 cm from one end to the other end as the second position. Use a near-infrared spectrophotometer (JASCO Corporation's "V-570") to measure the absorbance at each of the first position and the second position of the laminated glass X under the conditions of a bandwidth of 2 nm, a scanning speed of 1000 nm / minute, a scanning range of 1550 nm to 2050 nm, and a data acquisition interval of 0.5 nm. Then, at the same wavelength, average the absorbance at the first position and the absorbance at the second position, and make an absorbance spectrum from the averaged absorbance.

[0236] In the made absorbance spectrum, take the line connecting the position of the absorbance at a wavelength of 1873 nm and the position of the absorbance at a wavelength of 1984 nm as the baseline for absorbance A. Take the absolute value of the difference between the absorbance at a wavelength of 1930 nm on the baseline for absorbance A and the absorbance at a wavelength of 1930 nm on the made absorbance spectrum as the absorbance A at a wavelength of 1930 nm of the intermediate film.

[0237] The absolute value of the difference between the absorbance at a wavelength of 1670 nm and the absorbance at a wavelength of 1705 nm on the prepared absorbance spectrum is taken as the absorbance B at a wavelength of 1705 nm of the intermediate film.

[0238] In addition, the ratio (absorbance A / absorbance B) is calculated from the obtained absorbance A and absorbance B.

[0239] (2) Heat resistance test (haze value) at 100 °C

[0240] The obtained laminated glass (laminated glass X) is placed statically in a thermostat at 100 °C. For the laminated glass before being placed statically in the thermostat and the laminated glass after being placed statically in the thermostat for 7 days, 14 days, 28 days, and 56 days, the haze value is measured in the following manner.

[0241] In the obtained laminated glass (laminated glass X), the position 3 cm from one end to the other end is taken as the first position, and the position 5 cm from one end to the other end is taken as the second position. At the first position and the second position, the haze value is measured respectively according to JIS K6714. The average value of the haze value at the first position and the haze value at the second position is taken as the haze value of the laminated glass.

[0242] In addition, the value obtained by subtracting the haze value of the laminated glass before being placed statically in the thermostat from the haze value of the laminated glass after being placed statically in the thermostat for 56 days is taken as the change amount of the haze value (Day0~Day56).

[0243] The detailed situation and results are shown in Tables 2 to 5 below.

[0244] [Table 2]

[0245]

[0246] [Table 3]

[0247]

[0248] [Table 4]

[0249]

[0250] [Table 5]

[0251]

[0252] As shown in Tables 2 to 4, when the ratio (absorbance A / absorbance B) is 0.50 or less, even if the interlayer film has a polyethylene terephthalate film, when the laminated glass is subjected to a heat resistance test at 100°C, the haze value can be suppressed to a low level. On the other hand, as shown in Table 5, when the interlayer film does not have a polyethylene terephthalate film, when performing a heat resistance test at 100°C, there will be no problem of the haze value of the laminated glass becoming high.

[0253] Symbol Explanation

[0254] 1…Polyethylene terephthalate film

[0255] 1a…First surface

[0256] 1b…Second surface

[0257] 2…First resin layer

[0258] 2a…Outer surface

[0259] 3…Second resin layer

[0260] 3a…Outer surface

[0261] 11…Interlayer film

[0262] 11a…First surface

[0263] 11b…Second surface

[0264] 21…First laminated glass component

[0265] 22…Second laminated glass component

[0266] 31…Laminated glass

Claims

1. An interlayer film for laminated glass, which sequentially includes: a first resin layer containing a thermoplastic resin, a polyethylene terephthalate film, and a second resin layer containing a thermoplastic resin, wherein the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm of the interlayer film for laminated glass is 0.50 or less.

2. The interlayer film for laminated glass according to claim 1, wherein the polyethylene terephthalate film is a multilayer polyethylene terephthalate film having two or more polyethylene terephthalate layers and no metal layer, or the polyethylene terephthalate film is a polyethylene terephthalate film containing a metal layer having a polyethylene terephthalate layer and a metal layer.

3. The interlayer film for laminated glass according to claim 1 or 2, wherein the thermoplastic resin contained in the first resin layer contains a polyvinyl acetal resin, the thermoplastic resin contained in the second resin layer contains a polyvinyl acetal resin.

4. A method for manufacturing the interlayer film for laminated glass according to any one of claims 1 to 3, which includes: a step of obtaining a laminate that sequentially includes: a layer for forming a first resin layer containing a thermoplastic resin, a polyethylene terephthalate film, and a layer for forming a second resin layer containing a thermoplastic resin; and a step of curing the laminate in such a manner that the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm in the obtained interlayer film is 0.50 or less.

5. A method for manufacturing the interlayer film for laminated glass according to any one of claims 1 to 3, which includes: a step of curing at least one of the layer for forming a first resin layer containing a thermoplastic resin and the layer for forming a second resin layer containing a thermoplastic resin in such a manner that the ratio of the absorbance A at a wavelength of 1930 nm to the absorbance B at a wavelength of 1705 nm in the obtained interlayer film is 0.50 or less.

6. A laminated glass, which includes: a first laminated glass component; a second laminated glass component; and the interlayer film for laminated glass according to any one of claims 1 to 3, wherein the interlayer film for laminated glass is disposed between the first laminated glass component and the second laminated glass component.

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