Laminated glass interlayer film and laminated glass

Abstract

To provide an interlayer film for laminated glass capable of suppressing occurrence of foaming in an end part of the laminated glass, and increasing the transparency of the laminated glass without conducting a high-temperature and high-pressure process by means of an autoclave.SOLUTION: An interlayer film for laminated glass according to the present invention is an interlayer film for laminated glass having a one-layer structure or a two or more-layer structure, and includes a first layer having a thickness of 200 μm or more and 900 μm or less. When the thickness of the first layer is defined as TB μm, and a test sample B having a diameter of 8 mm and a thickness of TB μm obtained by cutting out the first layer is subjected to a predetermined compression creep test, a variation in thickness of the test sample B before and after the compression creep test is 50 μm or more and 325 μm or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an interlayer film for laminated glass used to obtain laminated glass. Further, the present invention relates to laminated glass using the above-mentioned interlayer film for laminated glass.

Background Art

[0002] Laminated glass has excellent safety in that even when it is damaged by an external impact, the amount of scattered glass fragments is small. For this reason, the above-mentioned laminated glass is widely used in automobiles, railway vehicles, airplanes, ships, buildings, and the like.

[0003] Generally, the above-mentioned laminated glass is manufactured by sandwiching an interlayer film for laminated glass between two glass plates and then performing high-temperature and high-pressure treatment using an autoclave to press-bond the interlayer film and the glass plates (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The high-temperature and high-pressure treatment using an autoclave during the production of laminated glass is performed under conditions such as 130°C or higher and 1 MPa or higher. However, the high-temperature and high-pressure treatment using an autoclave is a process that requires a large amount of equipment investment and also a process with a large amount of carbon dioxide emissions.

[0006]

[0007] ​On one hand, when manufacturing laminated glass using a conventional interlayer film without subjecting it to high temperature and high pressure treatment in an autoclave, foaming may occur at the edges of the laminated glass, or the transparency of the laminated glass may decrease.

[0008] An object of the present invention is to provide an interlayer film for laminated glass that can suppress the generation of foaming at the edges of the laminated glass and enhance the transparency of the laminated glass without performing high temperature and high pressure treatment in an autoclave. Another object of the present invention is to provide a laminated glass using the above-mentioned interlayer film for laminated glass.

Means for Solving the Problems

[0009] According to a broad aspect of the present invention, there is provided an interlayer film for laminated glass having a single-layer structure or a multi-layer structure of two or more layers, comprising a first layer. When a test sample A with a diameter of 8 mm and a thickness of 0.8 mm obtained by cutting out the first layer is subjected to the following compression creep test, the change amount of the thickness of the test sample A before and after the compression creep test is 50 μm or more and 325 μm or less. (In this specification, the "interlayer film for laminated glass" may be abbreviated as "interlayer film").

[0010] Compression creep test: With a load of 410 g applied to the test sample A, the temperature is raised from 30°C to 90°C at a rate of 6°C / min and held at 90°C for 5 minutes. The absolute value of the difference between the thickness of the test sample A at 30°C immediately after holding at 30°C for 5 minutes before starting the compression creep test and the thickness of the test sample A at 90°C immediately after holding at 90°C for 5 minutes at the end of the compression creep test is defined as the change amount of the thickness of the test sample A before and after the compression creep test.

[0011] According to a broad aspect of the present invention, there is provided an interlayer film for laminated glass having a single-layer structure or a multi-layer structure of two or more layers, comprising a first layer with a thickness of 200 μm or more and 900 μm or less. Let the thickness of the first layer be T B μm, and the diameter is 8 mm and the thickness is T BWhen a compression creep test is performed on a test sample B of [[ID=]], the amount of change in the thickness of the test sample B before and after the compression creep test is 50 [[ID=]]m or more and 325 [[ID=]]m or less, and an interlayer film for laminated glass (in this specification, the "interlayer film for laminated glass" may be abbreviated as "interlayer film") is provided.

[0012] Compression creep test: With a load of 410 g applied to the test sample B, the temperature is raised from 30 °C to 90 °C at a rate of 6 °C / min and held at 90 °C for 5 minutes. The absolute value of the difference between the thickness of the test sample B at 30 °C immediately after holding at 30 °C for 30 minutes before starting the compression creep test and the thickness of the test sample B at 90 °C immediately after holding at 90 °C for 5 minutes at the end of the compression creep test is defined as the amount of change in the thickness of the test sample B before and after the compression creep test.

[0013] According to a broad aspect of the present invention, there is provided an interlayer film for laminated glass having a single-layer structure or a structure of two or more layers, comprising a first layer, the thickness of the interlayer film being 80 [[ID=]]m or more and 1600 [[ID=]]m or less, and the thickness of the interlayer film being T C [[ID=]]m, and for a test sample C having a diameter of 8 mm and a thickness of T C [[ID=]]m obtained by cutting out the interlayer film, when the following compression creep test is performed, the amount of change in the thickness of the test sample C before and after the compression creep test is 50 [[ID=]]m or more and 325 [[ID=]]m or less, and an interlayer film for laminated glass (in this specification, the "interlayer film for laminated glass" may be abbreviated as "interlayer film") is provided.

[0014] Compression creep test: With a load of 410 g applied to the test sample C, the temperature is raised from 30 °C to 90 °C at a rate of 6 °C / min and held at 90 °C for 5 minutes. The absolute value of the difference between the thickness of the test sample C at 30 °C at the start of the compression creep test and the thickness of the test sample C at 90 °C immediately after holding at 90 °C for 5 minutes at the end of the compression creep test is defined as the amount of change in the thickness of the test sample C before and after the compression creep test.

[0015] In a specific aspect of the interlayer film according to the present invention, the first layer contains a thermoplastic resin and a plasticizer.

[0016] In a specific aspect of the interlayer film according to the present invention, the thermoplastic resin contained in the first layer is a polyvinyl acetal resin.

[0017] In a specific aspect of the interlayer film according to the present invention, the interlayer film has a structure of two or more layers, further includes a second layer, and the second layer is disposed on the first surface side of the first layer.

[0018] In a specific aspect of the interlayer film according to the present invention, the first layer is a surface layer in the interlayer film.

[0019] According to a broad aspect of the present invention, there is provided a laminated glass including a first laminated glass member, a second laminated glass member, and the above-described interlayer film for laminated glass, wherein the interlayer film for laminated glass is disposed between the first laminated glass member and the second laminated glass member.

Advantages of the Invention

[0020] The interlayer film according to the present invention has a structure of one layer or two or more layers. The interlayer film according to the present invention includes a first layer. In the interlayer film according to the present invention, when the above-described compression creep test is performed on a test sample A having a diameter of 8 mm and a thickness of 0.8 mm obtained by cutting out the first layer, the change amount of the thickness of the test sample A before and after the compression creep test is 50 μm or more and 325 μm or less. In the interlayer film according to the present invention, since the above-described configuration is provided, generation of foaming can be suppressed at the edge of the laminated glass, and the transparency of the laminated glass can be enhanced without performing high-temperature and high-pressure treatment by an autoclave.

[0021] The interlayer film according to the present invention has a structure of one layer or two or more layers. The interlayer film according to the present invention includes a first layer having a thickness of 200 μm or more and 900 μm or less. In the interlayer film according to the present invention, let the thickness of the first layer be T B μm, and the diameter is 8 mm and the thickness is T obtained by cutting out the first layer BWhen the above compression creep test was performed on the test sample B of μm, the amount of change in the thickness of the test sample B before and after the compression creep test was 50 μm or more and 325 μm or less. In the interlayer film according to the present invention, since the above configuration is provided, the generation of foaming can be suppressed at the edge of the laminated glass without performing high-temperature and high-pressure treatment by an autoclave, and the transparency of the laminated glass can be enhanced.

[0022] The interlayer film according to the present invention has a single-layer structure or a structure of two or more layers. The interlayer film according to the present invention includes a first layer. In the interlayer film according to the present invention, the thickness of the interlayer film is 80 μm or more and 1600 μm or less. In the interlayer film according to the present invention, the thickness of the interlayer film is denoted as T C μm, and for the test sample C having a diameter of 8 mm and a thickness of T C μm obtained by cutting out the interlayer film, when the above compression creep test was performed, the amount of change in the thickness of the test sample C before and after the compression creep test was 50 μm or more and 325 μm or less. In the interlayer film according to the present invention, since the above configuration is provided, the generation of foaming can be suppressed at the edge of the laminated glass without performing high-temperature and high-pressure treatment by an autoclave, and the transparency of the laminated glass can be enhanced.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0024] Hereinafter, the details of the present invention will be described.

[0025] (Interlayer for laminated glass) The interlayer for laminated glass according to the present invention (hereinafter, may be abbreviated as "interlayer") has a single-layer structure or a structure of two or more layers. The interlayer according to the present invention includes a first layer. In the interlayer according to the present invention, for test sample A having a diameter of 8 mm and a thickness of 0.8 mm obtained by cutting out the first layer, when the following compression creep test is performed, the change amount of the thickness of test sample A before and after the compression creep test is 50 μm or more and 325 μm or less.

[0026] Compression creep test: With a load of 410 g applied to test sample A, the temperature is raised from 30°C to 90°C at a rate of 6°C / min and held at 90°C for 5 minutes. The absolute value of the difference between the thickness of test sample A at 30°C immediately after holding at 30°C for 5 minutes before starting the compression creep test and the thickness of test sample A at 90°C immediately after holding at 90°C for 5 minutes at the end of the compression creep test is defined as the change amount of the thickness of test sample A before and after the compression creep test.

[0027] Specifically, a load of 410 g is applied to test sample A in an environment of 30°C, and this load is applied and held at 30°C for 5 minutes, and the thickness of test sample A at 30°C immediately after holding at 30°C for 5 minutes is measured. Also, a load of 410 g is applied to test sample A in an environment of 30°C, and this load is applied and held at 30°C for 5 minutes, then the temperature is raised from 30°C to 90°C at a rate of 6°C / min, and then held at 90°C for 5 minutes, and the thickness of test sample A at 90°C immediately after holding at 90°C for 5 minutes is measured. Until the thickness of test sample A at 90°C immediately after holding at 90°C for 5 minutes is measured, a load of 410 g is applied to test sample A, and the thickness is measured while the load is applied.

[0028] The interlayer film for laminated glass according to the present invention (hereinafter sometimes abbreviated as "interlayer film") has a single-layer structure or a structure of two or more layers. The interlayer film according to the present invention includes a first layer having a thickness of 200 μm or more and 900 μm or less. In the interlayer film according to the present invention, the thickness of the first layer is T B μm, and for a test sample B having a diameter of 8 mm and a thickness of T B μm obtained by cutting out the first layer, when the following compression creep test is performed, the amount of change in the thickness of the test sample B before and after the compression creep test is 50 μm or more and 325 μm or less.

[0029] Compression creep test: With a load of 410 g applied to the test sample B, the temperature is raised from 30°C to 90°C at a rate of 6°C / min and held at 90°C for 5 minutes. The absolute value of the difference between the thickness of the test sample B at 30°C immediately after holding at 30°C for 30 minutes before starting the compression creep test and the thickness of the test sample B at 90°C immediately after holding at 90°C for 5 minutes at the end of the compression creep test is defined as the amount of change in the thickness of the test sample B before and after the compression creep test.

[0030] Specifically, a load of 410 g is applied to the test sample B in an environment of 30°C, and in this state with the load applied, it is held at 30°C for 30 minutes, and the thickness of the test sample B at 30°C immediately after holding at 30°C for 30 minutes is measured. Also, a load of 410 g is applied to the test sample B in an environment of 30°C, and in this state with the load applied, it is held at 30°C for 30 minutes, then the temperature is raised from 30°C to 90°C at a rate of 6°C / min, and then held at 90°C for 5 minutes, and the thickness of the test sample B at 90°C immediately after holding at 90°C for 5 minutes is measured. Until the thickness of the test sample B at 90°C immediately after holding at 90°C for 5 minutes is measured, a load of 410 g is applied to the test sample B, and the thickness is measured with the load applied.

[0031] The interlayer film for laminated glass according to the present invention (hereinafter sometimes abbreviated as "interlayer film") has a single-layer structure or a structure of two or more layers. The interlayer film according to the present invention includes a first layer. In the interlayer film according to the present invention, the thickness of the interlayer film is 80 μm or more and 1600 μm or less. In the interlayer film according to the present invention, the thickness of the interlayer film is TC is μm, and for the test sample C with a diameter of 8 mm and a thickness of T obtained by cutting out the intermediate film C μm, when the following compression creep test was carried out, the change amount of the thickness of the test sample C before and after the compression creep test is 50 μm or more and 325 μm or less.

[0032] Compression creep test: With a load of 410 g applied to the test sample C, the temperature is raised from 30 °C to 90 °C at a rate of 6 °C / min and held at 90 °C for 5 minutes. The absolute value of the difference between the thickness of the test sample C at 30 °C at the start of the compression creep test and the thickness of the test sample C immediately after holding at 90 °C for 5 minutes at the end of the compression creep test is defined as the change amount of the thickness of the test sample C before and after the compression creep test.

[0033] Specifically, a load of 410 g is applied to the test sample C in an environment of 30 °C, and the thickness of the test sample C at 30 °C immediately after applying this load is measured. Also, a load of 410 g is applied to the test sample C in an environment of 30 °C, and in this state with the load applied, the temperature is raised from 30 °C to 90 °C at a rate of 6 °C / min immediately after applying this load, and then held at 90 °C for 5 minutes, and the thickness of the test sample C at 90 °C immediately after holding at 90 °C for 5 minutes is measured. Until the thickness of the test sample C at 90 °C immediately after holding at 90 °C for 5 minutes is measured, a load of 410 g is applied to the test sample C, and the thickness is measured with the load applied.

[0034] In the intermediate film according to the present invention, since the above configuration is provided, it is possible to suppress the generation of foaming at the edge of the laminated glass and enhance the transparency of the laminated glass without performing high-temperature and high-pressure treatment by an autoclave.

[0035] In the interlayer film according to the present invention, laminated glass can be manufactured under conditions of low temperature and low pressure (for example, 100°C or lower and 0.5 MPa or lower) as compared with high-temperature and high-pressure treatment by an autoclave. Therefore, laminated glass can be manufactured without a large amount of equipment investment in equipment such as autoclave facilities, and the amount of carbon dioxide emissions during the manufacture of laminated glass can be reduced. Furthermore, the production capacity by the conventional method for manufacturing laminated glass in which autoclave treatment is performed can be maintained.

[0036] Also, in the interlayer film according to the present invention, the penetration resistance of the laminated glass can be enhanced.

[0037] The interlayer film according to the present invention has a single-layer structure or a structure of two or more layers. The interlayer film according to the present invention may have a single-layer structure, may have a two-layer structure, may have a structure of two or more layers, may have a three-layer structure, may have a structure of three or more layers, or may have a structure of four or more layers. The interlayer film according to the present invention includes a first layer. The interlayer film according to the present invention may be a single-layer interlayer film including only the first layer, or may be a multi-layer interlayer film including the first layer and other layers.

[0038] The above interlayer film may have a structure of two or more layers, and may include a second layer in addition to the first layer. When the above interlayer film includes the second layer, the second layer is disposed on the first surface side of the first layer.

[0039] When the above interlayer film is a multi-layer interlayer film having a structure of two or more layers, the interlayer film has a first surface layer and a second surface layer.

[0040] It is preferable that the above intermediate film includes the above first layer as a surface layer in the intermediate film. The above first layer is preferably the surface layer of the intermediate film. It is preferable that the above intermediate film includes the above first layer as the above first surface layer, and it is more preferable that the above first layer is included as the above first surface layer and the above second surface layer. In this case, the effects of the present invention can be more effectively exerted. When the above intermediate film is a single-layer intermediate film including only the above first layer, the first layer is the surface layer.

[0041] The above intermediate film may have a structure of three or more layers, and may include a third layer in addition to the above first layer and the above second layer. When the above intermediate film includes the above third layer, the third layer is disposed on the surface side opposite to the above first layer of the above second layer.

[0042] Hereinafter, the compression creep test performed in the present invention will be described more specifically.

[0043] Test sample A is a test sample with a diameter of 8 mm and a thickness of 0.8 mm obtained by cutting out the first layer. The test sample A can be produced by pressing and molding at 150 °C after peeling the layer to be measured (the first layer) from the intermediate film. The test sample A is produced for performing a compression creep test.

[0044] Test sample B is produced using a first layer having a thickness of 200 μm or more and 900 μm or less. When the thickness of the above first layer is T B μm, the test sample B is a test sample with a diameter of 8 mm and a thickness of T B μm obtained by cutting out the first layer. Therefore, the thickness of the above first layer and the thickness of the test sample B are the same.

[0045] Test sample C is produced using an intermediate film having a thickness of 80 μm or more and 1600 μm or less. When the thickness of the above intermediate film is T C μm, the test sample C is a test sample with a diameter of 8 mm and a thickness of T CIt is a test sample of μm. Therefore, the thickness of the above intermediate film is the same as the thickness of the above test sample C.

[0046] In the above compression creep test, test samples A, B, and C are placed between a first jig having a circular surface with a diameter of 8 mm and a second jig having a circular surface with a diameter of 8 mm. With a load of 410 g applied in the thickness direction of test samples A, B, and C, the temperature is raised from 30°C to 90°C at a rate of 6°C / min and held at 90°C for 5 minutes. The absolute value of the difference between the thicknesses of test samples A, B, and C at 30°C immediately after being held at 30°C for 5 minutes or 30 minutes before starting the compression creep test and the thicknesses of test samples A, B, and C at 90°C immediately after being held at 90°C for 5 minutes at the end of the compression creep test is taken as the amount of change in the thickness of test samples A, B, and C before and after the compression creep test. Usually, the thicknesses of test samples A, B, and C after the compression creep test are smaller than the thicknesses of test samples A, B, and C before the compression creep test.

[0047] Examples of the apparatus that can be used in the above compression creep test include, for example, a viscoelasticity measuring apparatus ("RSA-G2" manufactured by TA Instruments) and the like. Also, the thicknesses of test samples A, B, and C before and after the compression test can be measured by monitoring the gap between the compression measurement jigs of the viscoelasticity measuring apparatus. When using RSA-G2, it is advisable to set the transducer mode to a spring and perform the measurement.

[0048] In the above intermediate film, when the above compression creep test is performed on test sample A, the amount of change in the thickness of test sample A before and after the compression creep test is 50 μm or more and 325 μm or less. If the amount of change is less than 50 μm, the transparency of the laminated glass is likely to decrease. If the amount of change exceeds 325 μm, foaming is likely to occur at the edges of the laminated glass.

[0049] The amount of change in the thickness of test sample A before and after the compression creep test is preferably 75 μm or more, more preferably 100 μm or more, preferably 300 μm or less, and more preferably 250 μm or less. When the amount of change is at least the above lower limit, the transparency of the laminated glass can be further enhanced. When the amount of change is at most the above upper limit, the generation of foaming at the edge of the laminated glass can be more effectively suppressed.

[0050] In the above intermediate film, when the compression creep test is performed on test sample B, the amount of change in the thickness of test sample B before and after the compression creep test is 50 μm or more and 325 μm or less. When the amount of change is less than 50 μm, the transparency of the laminated glass is likely to decrease. When the amount of change exceeds 325 μm, foaming is likely to occur at the edge of the laminated glass.

[0051] The amount of change in the thickness of test sample B before and after the compression creep test is preferably 75 μm or more, more preferably 100 μm or more, preferably 300 μm or less, and more preferably 250 μm or less. When the amount of change is at least the above lower limit, the transparency of the laminated glass can be further enhanced. When the amount of change is at most the above upper limit, the generation of foaming at the edge of the laminated glass can be more effectively suppressed.

[0052] In the above intermediate film, when the compression creep test is performed on test sample C, the amount of change in the thickness of test sample C before and after the compression creep test is 50 μm or more and 325 μm or less. When the amount of change is less than 50 μm, the transparency of the laminated glass is likely to decrease. When the amount of change exceeds 325 μm, foaming is likely to occur at the edge of the laminated glass.

[0053] The amount of change in the thickness of test sample C before and after the compression creep test is preferably 75 μm or more, more preferably 100 μm or more, preferably 300 μm or less, and more preferably 250 μm or less. When the amount of change is at least the above lower limit, the transparency of the laminated glass can be further enhanced. When the amount of change is at most the above upper limit, the generation of foaming at the edge of the laminated glass can be more effectively suppressed.

[0054] Incidentally, examples of methods for controlling the amount of change in the thickness of test samples A, B, and C before and after the compression creep test within the above preferred ranges and the like include the following methods. (1) Increasing the average degree of polymerization of the thermoplastic resin contained in the first layer or the intermediate film decreases the amount of change. (2) Increasing the content of the plasticizer contained in the first layer or the intermediate film increases the amount of change. (3) Increasing the hydrogen bonding force of the resin contained in the first layer or the intermediate film decreases the amount of change. By appropriately combining these methods, the amount of change can be controlled within the above preferred ranges and the like.

[0055] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[0056] FIG. 1 is a cross-sectional view schematically showing an intermediate film for laminated glass according to a first embodiment of the present invention.

[0057] 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 surface layer 1, an intermediate layer 3, and a second surface layer 2. The interlayer film 11 has a three-layer structure. The intermediate layer 3 is disposed and laminated on the first surface 1a of the first surface layer 1. The intermediate layer 3 is disposed and laminated on the first surface 2a of the second surface layer 2. The first surface layer 1 and the second surface layer 2 are each the first layer described above. A second layer, which is the intermediate layer 3, is disposed on the first surface side of the first layer, which is the surface layer. The intermediate layer 3 is disposed between the first surface layer 1 and the second surface layer 2 and is sandwiched therebetween. Therefore, the interlayer film 11 has a multilayer structure (first layer / second layer / first layer) in which the first layer, the second layer, and the first layer are laminated in this order. In this case, the two first layers may be distinguished and referred to as the first layer A and the first layer B.

[0058] FIG. 2 is a cross-sectional view schematically showing an interlayer film for laminated glass according to a second embodiment of the present invention.

[0059] The interlayer film 11A shown in FIG. 2 is a single-layer interlayer film having a one-layer structure. The interlayer film 11A is the first layer. The interlayer film 11A is used to obtain laminated glass. The interlayer film 11A is an interlayer film for laminated glass.

[0060] FIG. 3 is a cross-sectional view schematically showing an interlayer film for laminated glass according to a third embodiment of the present invention.

[0061] The intermediate film 11B shown in Fig. 3 is a multilayer intermediate film having a structure of two or more layers. The intermediate film 11B is used to obtain laminated glass. The intermediate film 11B is an intermediate film for laminated glass. The intermediate film 11B includes a first surface layer 1B, a second intermediate layer 4B, a first intermediate layer 3B, a third intermediate layer 5B, and a second surface layer 2B. The intermediate film 11B has a five-layer structure. The second intermediate layer 4B is disposed and laminated on the first surface 1Ba of the first surface layer 1B. The third intermediate layer 5B is disposed and laminated on the first surface 2Ba of the second surface layer 2B. The first surface layer 1B and the second surface layer 2B are each the above-mentioned first layer. The second layer, which is the second intermediate layer 4B, is disposed on the first surface 1Ba side of the first layer, which is the first surface layer 1B. The third layer, which is the third intermediate layer 5B, is disposed on the first surface 2Ba side of the first layer, which is the second surface layer 2B. A functional film, which is the first intermediate layer 3B, is disposed and sandwiched between the second intermediate layer 4B and the third intermediate layer 5B. In this embodiment, the functional film is a light control film. Therefore, the intermediate film 11B has a multilayer structure (first layer / second layer / functional film / third layer / first layer) in which the first layer, the second layer, the functional film, the third layer, and the first layer are laminated in this order. In this case, the two first layers may be distinguished and referred to as the first layer A and the first layer B.

[0062] The glass transition temperature of the above-mentioned first layer or the surface layer is preferably 20°C or higher, more preferably 25°C or higher, still more preferably 30°C or higher, and preferably 45°C or lower, more preferably 40°C or lower, still more preferably 35°C or lower. When the glass transition temperature of the above-mentioned first layer or the surface layer is equal to or higher than the lower limit and equal to or lower than the upper limit, the effects of the present invention can be more effectively exerted. Further, when the glass transition temperature of the above-mentioned first layer or the surface layer is equal to or lower than the upper limit, the penetration resistance of the laminated glass can be further enhanced.

[0063] The softening point of the above-mentioned first layer or surface layer is preferably 45°C or higher, more preferably 50°C or higher, preferably 70°C or lower, and more preferably 65°C or lower. When the softening point of the above-mentioned first layer or the above-mentioned surface layer is equal to or higher than the above lower limit and equal to or lower than the above upper limit, the effects of the present invention can be more effectively exerted. Further, when the softening point of the above-mentioned first layer or the above-mentioned surface layer is equal to or lower than the above upper limit, the penetration resistance of the laminated glass can be further enhanced.

[0064] The above glass transition temperature and softening point are determined by viscoelasticity measurement. The viscoelasticity measurement is specifically performed as follows.

[0065] The test piece is stored in an environment of room temperature 23±2°C and humidity 25±5% for 12 hours. Then, using a viscoelasticity measuring device "ARES-G2" manufactured by TA Instruments, the viscoelasticity is measured. A parallel plate with a diameter of 8 mm is used as the jig, and the measurement is performed under the conditions of a shear mode, a temperature decrease rate of 3°C / min from 100°C to -20°C, and conditions of a frequency of 1 Hz and a strain of 1%. In the obtained measurement results, the peak temperature of the loss tangent is defined as the glass transition temperature Tg (°C). The temperature at which the value of the loss tangent becomes extremely small in the temperature range between Tg (°C) and 100°C is defined as the softening point.

[0066] The viscoelasticity measurement may be performed using the intermediate film itself. In this case, from the measurement results, the peak of tanδ derived from the above-mentioned first layer may be read. Regarding an intermediate film having a structure of two or more layers, the glass transition temperature of the layer to be measured may be measured after peeling between the layers. Further, in the case of laminated glass, after cooling the laminated glass with liquid nitrogen or the like, the laminated glass member and the intermediate film may be peeled, and the viscoelasticity measurement may be performed using the peeled intermediate film.

[0067] Hereinafter, the details of the intermediate film, the above-mentioned first layer, the above-mentioned second layer, the above-mentioned third layer, and each component used in the intermediate film according to the present invention will be described.

[0068] (Thermoplastic resin) The above intermediate film preferably contains a thermoplastic resin (hereinafter sometimes referred to as thermoplastic resin (0)). Examples of the above thermoplastic resin include polyvinyl acetate resin, polyester resin, polyvinyl acetal resin, vinyl acetate resin, polystyrene resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, polyurethane resin, ionomer resin, polyvinyl alcohol resin, polyolefin resins such as aliphatic polyolefin, and (meth)acrylic resins (polymers having a (meth)acryloyl group). Note that polyoxymethylene (or polyacetal) resin is included in the polyvinyl acetal resin. Other thermoplastic resins may be used as the above thermoplastic resin. The above thermoplastic resin may be a thermoplastic elastomer.

[0069] The above intermediate film preferably contains a polyvinyl acetal resin (hereinafter, may be referred to as polyvinyl acetal resin (0)) as the thermoplastic resin (0). The thermoplastic resin (0) contained in the above intermediate film is preferably a polyvinyl acetal resin (0). The above first layer (including a single-layer intermediate film) preferably contains a thermoplastic resin (hereinafter, may be referred to as thermoplastic resin (1)). The above first layer preferably contains a polyvinyl acetal resin (hereinafter, may be referred to as polyvinyl acetal resin (1)) as the thermoplastic resin (1). The thermoplastic resin (1) contained in the above first layer is preferably a polyvinyl acetal resin (1). The above second layer preferably contains a thermoplastic resin (hereinafter, may be referred to as thermoplastic resin (2)). The above second layer preferably contains a polyvinyl acetal resin (hereinafter, may be referred to as polyvinyl acetal resin (2)) or a polyester resin as the thermoplastic resin (2). The thermoplastic resin (2) contained in the above second layer is preferably a polyvinyl acetal resin (2) or a polyester resin. The above third layer preferably contains a thermoplastic resin (hereinafter, may be referred to as thermoplastic resin (3)) or a polyester resin. The above third layer preferably contains a polyvinyl acetal resin (hereinafter, may be referred to as polyvinyl acetal resin (3)) or a polyester resin as the thermoplastic resin (3). The thermoplastic resin (3) contained in the above third layer is preferably a polyvinyl acetal resin (3) or a polyester resin. The above thermoplastic resin (1), the above thermoplastic resin (2), and the above thermoplastic resin (3) may be the same or different. Since the sound insulation property becomes even higher, the above thermoplastic resin (1) is preferably different from the above thermoplastic resin (2) and the above thermoplastic resin (3). The above polyvinyl acetal resin (1), the above polyvinyl acetal resin (2), and the above polyvinyl acetal resin (3) may be the same or different. Since the sound insulation property becomes even higher, the above polyvinyl acetal resin (1) is preferably different from the above polyvinyl acetal resin (2) and the above polyvinyl acetal resin (3).Each of the above-mentioned thermoplastic resin (0), the above-mentioned thermoplastic resin (1), the above-mentioned thermoplastic resin (2), and the above-mentioned thermoplastic resin (3) may be used alone or in combination of two or more. Each of the above-mentioned polyvinyl acetal resin (0), the above-mentioned polyvinyl acetal resin (1), the above-mentioned polyvinyl acetal resin (2), and the above-mentioned polyvinyl acetal resin (3) may be used alone or in combination of two or more.

[0070] The above-mentioned polyvinyl acetal resin can be produced, for example, by acetalizing polyvinyl alcohol (PVA) with an aldehyde. The above-mentioned polyvinyl acetal resin is preferably an acetalized product of polyvinyl alcohol. The above-mentioned polyvinyl alcohol can be obtained, for example, by saponifying polyvinyl acetate. The saponification degree of the above-mentioned polyvinyl alcohol is generally in the range of 70 mol% to 99.9 mol%.

[0071] The average degree of polymerization of the above-mentioned 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, and most preferably 2700 or more, and preferably 5000 or less, more preferably 4000 or less, and further preferably 3500 or less. When the average degree of polymerization is at least the above lower limit, the penetration resistance of the laminated glass becomes even higher. When the average degree of polymerization is at most the above upper limit, the molding of the interlayer film becomes easier.

[0072] The average degree of polymerization of the above-mentioned polyvinyl alcohol is determined by a method conforming to JIS K6726 "Test Methods for Polyvinyl Alcohol".

[0073] The above polyvinyl acetal resin (1) may be a mixture of two or more polyvinyl acetal resins having different average degrees of polymerization of polyvinyl alcohol. In this case, the above polyvinyl acetal resin (1) is preferably a mixture of a first polyvinyl acetal resin (1A) having an average degree of polymerization of polyvinyl alcohol of 1500 or more and a second polyvinyl acetal resin (1B) having an average degree of polymerization of polyvinyl alcohol of 1000 or less.

[0074] The average degree of polymerization of polyvinyl alcohol in the above polyvinyl acetal resin (1) is preferably 900 or more, more preferably 1000 or more, preferably 1400 or less, and more preferably 1300 or less.

[0075] The average degree of polymerization of polyvinyl alcohol in the above first polyvinyl acetal resin (1A) is preferably 1500 or more, more preferably 1600 or more, preferably 2000 or less, and more preferably 1800 or less.

[0076] The average degree of polymerization of polyvinyl alcohol in the above second polyvinyl acetal resin (1B) is preferably 400 or more, more preferably 500 or more, preferably 1000 or less, and more preferably 900 or less.

[0077] When using a mixture of two or more polyvinyl acetal resins (1A) and (1B) having different average degrees of polymerization of polyvinyl alcohol, the absolute value of the difference in average degree of polymerization is preferably 500 or more, more preferably 600 or more, preferably 1200 or less, and more preferably 1100 or less.

[0078] In a total of 100% by weight of the above-mentioned first polyvinyl acetal resin (1A) and the above-mentioned second polyvinyl acetal resin (1B), the content of the above-mentioned second polyvinyl acetal resin (1B) is preferably 20% by weight or more, more preferably 25% by weight or more, preferably 80% by weight or less, and more preferably 75% by weight or less. When the content of the above-mentioned second polyvinyl acetal resin (1B) is within the above lower limit and the above upper limit, the effects of the present invention can be more effectively exerted.

[0079] The number of carbon atoms of the acetal group contained in the above polyvinyl acetal resin is not particularly limited. The aldehyde used when producing the above polyvinyl acetal resin is not particularly limited. The number of carbon atoms of the acetal group in the above polyvinyl acetal resin is preferably 3 to 5, and more preferably 3 or 4. When the number of carbon atoms of the acetal group in the above polyvinyl acetal resin is 3 or more, the glass transition temperature of the intermediate film becomes sufficiently low. The number of carbon atoms of the acetal group in the above polyvinyl acetal resin may also be 4 or 5.

[0080] The above aldehyde is not particularly limited. Generally, aldehydes having 1 to 10 carbon atoms are preferably used. Examples of the aldehyde having 1 to 10 carbon atoms include propionaldehyde, n-butylaldehyde, isobutylaldehyde, n-valeraldehyde, 2-ethylbutylaldehyde, n-hexylaldehyde, n-octylaldehyde, n-nonylaldehyde, n-decylaldehyde, formaldehyde, acetaldehyde, and benzaldehyde. The above aldehyde is preferably propionaldehyde, n-butylaldehyde, isobutylaldehyde, n-hexylaldehyde or n-valeraldehyde, more preferably propionaldehyde, n-butylaldehyde or isobutylaldehyde, and even more preferably n-butylaldehyde. The above aldehyde may be used alone or in combination of two or more.

[0081] The above intermediate film preferably contains polyvinyl butyral resin as the thermoplastic resin (0). The above intermediate film preferably contains polyvinyl butyral resin as the polyvinyl acetal resin (0). The thermoplastic resin (0) contained in the above intermediate film is preferably polyvinyl butyral resin. The above first layer preferably contains polyvinyl butyral resin as the thermoplastic resin (1). The above first layer preferably contains polyvinyl butyral resin as the polyvinyl acetal resin (1). The thermoplastic resin (1) contained in the above first layer is preferably polyvinyl butyral resin. The above second layer preferably contains polyvinyl butyral resin as the thermoplastic resin (2). The above second layer preferably contains polyvinyl butyral resin as the polyvinyl acetal resin (2). The thermoplastic resin (2) contained in the above second layer is preferably polyvinyl butyral resin. The above third layer preferably contains polyvinyl butyral resin as the thermoplastic resin (3). The above third layer preferably contains polyvinyl butyral resin as the polyvinyl acetal resin (3). The thermoplastic resin (3) contained in the above third layer is preferably polyvinyl butyral resin. The polyvinyl butyral resins contained in the above intermediate film, the above first layer, the above second layer, and the above third layer may each be used alone or in combination of two or more.

[0082] The hydroxyl group content (amount of hydroxyl groups) of the above polyvinyl acetal resin (0) is preferably 15 mol% or more, more preferably 18 mol% or more, preferably 40 mol% or less, and more preferably 35 mol% or less. When the hydroxyl group content is at least the above lower limit, the adhesive strength of the intermediate film becomes even higher. Also, when the hydroxyl group content is at most the above upper limit, the flexibility of the intermediate film increases and the handling of the intermediate film becomes easier.

[0083] The hydroxyl group content (amount of hydroxyl groups) of the above-mentioned polyvinyl acetal resin (1) is preferably 25 mol% or more, more preferably 28 mol% or more, still more preferably 30 mol% or more, even more preferably 31.5 mol% or more, still more preferably 32 mol% or more, and particularly preferably 33 mol% or more. The hydroxyl group content (amount of hydroxyl groups) of the above-mentioned polyvinyl acetal resin (1) is preferably 38 mol% or less, more preferably 37 mol% or less, still more preferably 36.5 mol% or less, and particularly preferably 36 mol% or less. When the content of the above-mentioned hydroxyl groups is at least the above lower limit, the adhesive strength of the interlayer film becomes even higher. Also, when the content of the above-mentioned hydroxyl groups is at most the above upper limit, the flexibility of the interlayer film becomes high and the handling of the interlayer film becomes easy.

[0084] The respective hydroxyl group contents of the above-mentioned polyvinyl acetal resin (2) and the above-mentioned polyvinyl acetal resin (3) are preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 17 mol% or more, and preferably 25 mol% or less, more preferably 20 mol% or less, still more preferably 19 mol% or less, and particularly preferably 18 mol% or less. When the content of the above-mentioned hydroxyl groups is at least the above lower limit, the mechanical strength of the interlayer film becomes even higher. In particular, when the hydroxyl group content of the above-mentioned polyvinyl acetal resins (2) and (3) is 15 mol% or more, the reaction efficiency is high and the productivity is excellent, and when it is 25 mol% or less, the sound insulation property of the laminated glass becomes even higher. Also, when the content of the above-mentioned hydroxyl groups is at most the above upper limit, the flexibility of the interlayer film becomes high and the handling of the interlayer film becomes easy.

[0085] From the viewpoint of further enhancing the sound insulation property, the hydroxyl group content of the above polyvinyl acetal resin (1) is preferably higher than the hydroxyl group content of the above polyvinyl acetal resin (2). From the viewpoint of further enhancing the sound insulation property, the hydroxyl group content of the above polyvinyl acetal resin (1) is preferably higher than the hydroxyl group content of the above polyvinyl acetal resin (3). From the viewpoint of further enhancing the sound insulation property, the absolute value of the difference between the hydroxyl group content of the above polyvinyl acetal resin (1) and the hydroxyl group content of the above polyvinyl acetal resin (2) is preferably 1 mol% or more, more preferably 5 mol% or more, still more preferably 9 mol% or more, particularly preferably 10 mol% or more, and most preferably 12 mol% or more. From the viewpoint of further enhancing the sound insulation property, the absolute value of the difference between the hydroxyl group content of the above polyvinyl acetal resin (1) and the hydroxyl group content of the above polyvinyl acetal resin (3) is preferably 1 mol% or more, more preferably 5 mol% or more, still 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 above polyvinyl acetal resin (1) and the hydroxyl group content of the above polyvinyl acetal resin (2), and the absolute value of the difference between the hydroxyl group content of the above polyvinyl acetal resin (1) and the hydroxyl group content of the above polyvinyl acetal resin (3) are preferably 20 mol% or less.

[0086] The hydroxyl group content of the above polyvinyl acetal resin is a value obtained by expressing, as a percentage, the molar fraction obtained by dividing the amount of ethylene groups to which hydroxyl groups are bonded by the total amount of ethylene groups in the main chain. The amount of ethylene groups to which the above hydroxyl groups are bonded can be measured, for example, in accordance with JIS K6728 "Test Methods for Polyvinyl Butyral".

[0087] The degree of acetylation (acetyl group content) of the above polyvinyl acetal resin (0) is preferably 0.1 mol% or more, more preferably 0.3 mol% or more, still more preferably 0.5 mol% or more, and preferably 30 mol% or less, more preferably 25 mol% or less, still more preferably 20 mol% or less. When the degree of acetylation is at least the above lower limit, the compatibility between the polyvinyl acetal resin and the plasticizer increases. When the degree of acetylation is at most the above upper limit, the moisture resistance of the interlayer film and the laminated glass increases.

[0088] The degree of acetylation (acetyl group content) of the above polyvinyl acetal resin (1) 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 degree of acetylation is at least the above lower limit, the compatibility between the polyvinyl acetal resin and the plasticizer increases. When the degree of acetylation is at most the above upper limit, the moisture resistance of the interlayer film and the laminated glass increases.

[0089] The degree of acetylation of each of the above polyvinyl acetal resin (2) and the above polyvinyl acetal resin (3) is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, even more preferably 7 mol% or more, still more preferably 9 mol% or more, and preferably 30 mol% or less, more preferably 25 mol% or less, still more preferably 24 mol% or less, particularly preferably 20 mol% or less. When the degree of acetylation is at least the above lower limit, the compatibility between the polyvinyl acetal resin and the plasticizer increases. When the degree of acetylation is at most the above upper limit, the moisture resistance of the interlayer film and the laminated glass increases. In particular, when the degree of acetylation of the above polyvinyl acetal resins (2) and (3) is 0.1 mol% or more and 25 mol% or less, the penetration resistance is excellent.

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

[0091] The degree of acetalization of the above polyvinyl acetal resin (0) (in the case of polyvinyl butyral resin, the degree of butyralization) is preferably 60 mol% or more, more preferably 63 mol% or more, preferably 85 mol% or less, more preferably 75 mol% or less, and still more preferably 70 mol% or less. When the degree of acetalization is at least the above lower limit, the compatibility between the polyvinyl acetal resin and the plasticizer increases. When the degree of acetalization is at most the above upper limit, the reaction time required for producing the polyvinyl acetal resin becomes shorter.

[0092] The degree of acetalization of the above polyvinyl acetal resin (1) (in the case of polyvinyl butyral resin, the degree of butyralization) is preferably 55 mol% or more, more preferably 60 mol% or more, preferably 75 mol% or less, more preferably 71 mol% or less. When the degree of acetalization is at least the above lower limit, the compatibility between the polyvinyl acetal resin and the plasticizer increases. When the degree of acetalization is at most the above upper limit, the reaction time required for producing the polyvinyl acetal resin becomes shorter.

[0093] The degree of acetalization of each of the above polyvinyl acetal resin (2) and the above polyvinyl acetal resin (3) (in the case of polyvinyl butyral resin, the degree of butyralization) is preferably 47 mol% or more, more preferably 60 mol% or more, preferably 85 mol% or less, more preferably 80 mol% or less, and still more preferably 75 mol% or less. When the degree of acetalization is at least the above lower limit, the compatibility between the polyvinyl acetal resin and the plasticizer increases. When the degree of acetalization is at most the above upper limit, the reaction time required for producing the polyvinyl acetal resin becomes shorter.

[0094] The degree of acetalization is determined as follows. First, a value obtained by subtracting the amount of ethylene groups to which a hydroxyl group is bonded and the amount of ethylene groups to which an acetyl group is bonded from the total amount of ethylene groups in the main chain is determined. The obtained value is divided by the total amount of ethylene groups in the main chain to obtain a mole fraction. The value obtained by expressing this mole fraction as a percentage is the degree of acetalization.

[0095] In addition, the hydroxyl group content (amount of hydroxyl groups), degree of acetalization (degree of butyralization), and degree of acetylation are preferably calculated from the results measured by a method in accordance with JIS K6728, "Test Methods for Polyvinyl Butyral". However, measurement according to ASTM D1396-92 may also be used. When the polyvinyl acetal resin is a polyvinyl butyral resin, the hydroxyl group content (amount of hydroxyl groups), the degree of acetalization (degree of butyralization), and the degree of acetylation can be calculated from the results measured by a method in accordance with JIS K6728, "Test Methods for Polyvinyl Butyral".

[0096] In 100% by weight of the thermoplastic resin contained in the intermediate film, 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, most preferably 90% by weight or more. In 100% by weight of the thermoplastic resin contained in the intermediate film, the content of the polyvinyl acetal resin is preferably 100% by weight or less. It is preferable that the main component (50% by weight or more) of the thermoplastic resin of the intermediate film is a polyvinyl acetal resin.

[0097] In 100% by weight of the thermoplastic resin contained in the first 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, most preferably 90% by weight or more. In 100% by weight of the thermoplastic resin contained in the first layer, the content of the polyvinyl acetal resin is preferably 100% by weight or less. It is preferable that the main component (50% by weight or more) of the thermoplastic resin of the first layer is a polyvinyl acetal resin.

[0098] (Plasticizer) The above intermediate film preferably contains a plasticizer. The above first layer (including a single-layer intermediate film) preferably contains a plasticizer (hereinafter sometimes referred to as plasticizer (1)). The above second layer preferably contains a plasticizer (hereinafter sometimes referred to as plasticizer (2)). The above third layer preferably contains a plasticizer (hereinafter sometimes referred to as plasticizer (3)). By using a plasticizer and also by using a combination of a polyvinyl acetal resin and a plasticizer, the impact resistance and penetration resistance are further improved, and the adhesive force to a laminated glass member or other layer containing the polyvinyl acetal resin and the plasticizer becomes moderately high. The above plasticizer is not particularly limited. The above plasticizer (1), the above plasticizer (2), and the above plasticizer (3) may be the same or different. Each of the above plasticizer (1), the above plasticizer (2), and the above plasticizer (3) may be used alone or in combination of two or more.

[0099] Examples of the above plasticizer include organic ester plasticizers such as monobasic organic acid esters and polybasic organic acid esters, and organic phosphoric acid plasticizers such as organic phosphoric acid plasticizers and organic phosphorous acid plasticizers. The above plasticizer is preferably an organic ester plasticizer. The above plasticizer is preferably a liquid plasticizer.

[0100] Examples of the above monobasic organic acid ester include glycol esters obtained by reacting glycol with a monobasic organic acid. Examples of the above glycol include triethylene glycol, tetraethylene glycol, and tripropylene glycol. Examples of the above monobasic organic acid include butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptanoic acid, n-octylic acid, 2-ethylhexanoic acid, n-nonanoic acid, decanoic acid, and benzoic acid.

[0101] Examples of the above 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 above polybasic organic acid include adipic acid, sebacic acid, and azelaic acid.

[0102] Examples of the above-mentioned organic ester plasticizers 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, diethylene glycol di-2-ethylbutyrate, 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, hexyl cyclohexyl adipate, a mixture of heptyl adipate and nonyl adipate, diisononyl adipate, diisodecyl adipate, heptyl nonyl adipate, dibutyl sebacate, oil-modified sebacic acid alkyd, and a mixture of phosphate ester and adipic acid ester. Organic ester plasticizers other than these may also be used. Other adipic acid esters other than the above-mentioned adipic acid esters may also be used.

[0103] Examples of the above-mentioned organic phosphate plasticizers include tributoxyethyl phosphate, isodecyl phenyl phosphate, and triisopropyl phosphate.

[0104] The above plasticizer is preferably a diester plasticizer represented by the following formula (1).

[0105]

Chemical formula

[0106] 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 are preferably each an organic group having 5 to 10 carbon atoms, and more preferably an organic group having 6 to 10 carbon atoms.

[0107] The plasticizer preferably contains triethylene glycol di-2-ethylhexanoate (3GO), triethylene glycol di-2-ethylbutyrate (3GH) or triethylene glycol di-2-ethylpropanoate. The plasticizer more preferably contains triethylene glycol di-2-ethylhexanoate (3GO) or triethylene glycol di-2-ethylbutyrate (3GH), and still more preferably contains triethylene glycol di-2-ethylhexanoate.

[0108] In the above first layer, the content of the plasticizer (1) with respect to 100 parts by weight of the thermoplastic resin (1) (when the thermoplastic resin (1) is a polyvinyl acetal resin (1), 100 parts by weight of the polyvinyl acetal resin (1)) is defined as content (1). The content (1) is preferably 20 parts by weight or more, more preferably 25 parts by weight or more, still more preferably 28 parts by weight or more, preferably 40 parts by weight or less, more preferably 38 parts by weight or less, still more preferably 35 parts by weight or less, and particularly preferably 33 parts by weight or less. When the content (1) is at least the above lower limit, the flexibility of the intermediate film increases and the handling of the intermediate film becomes easy. When the content (1) is at least the above lower limit, the flexibility of the intermediate film increases and the handling of the intermediate film becomes easy. When the content (1) is at most the above upper limit, the flexural rigidity becomes even higher. When the content (1) is at least the above lower limit and at most the above upper limit, the effects of the present invention can be more effectively exerted.

[0109] In the second layer, the content of the plasticizer (2) with respect to 100 parts by weight of the thermoplastic resin (2) (when the thermoplastic resin (2) is a polyvinyl acetal resin (2), 100 parts by weight of the polyvinyl acetal resin (2)) is defined as the content (2). The content (2) is preferably 50 parts by weight or more, more preferably 55 parts by weight or more, still more preferably 60 parts by weight or more, preferably 100 parts by weight or less, more preferably 90 parts by weight or less, still more preferably 85 parts by weight or less, and particularly preferably 80 parts by weight or less. When the content (2) is at least the lower limit, the flexibility of the intermediate film increases and the handling of the intermediate film becomes easier. When the content (2) is at most the upper limit, the penetration resistance of the laminated glass becomes even higher.

[0110] In the third layer, the content of the plasticizer (3) with respect to 100 parts by weight of the thermoplastic resin (3) (when the thermoplastic resin (3) is a polyvinyl acetal resin (3), 100 parts by weight of the polyvinyl acetal resin (3)) is defined as the content (3). The content (3) is preferably 50 parts by weight or more, more preferably 55 parts by weight or more, still more preferably 60 parts by weight or more, preferably 100 parts by weight or less, more preferably 90 parts by weight or less, still more preferably 85 parts by weight or less, and particularly preferably 80 parts by weight or less. When the content (3) is at least the lower limit, the flexibility of the intermediate film increases and the handling of the intermediate film becomes easier. When the content (3) is at most the upper limit, the penetration resistance of the laminated glass becomes even higher.

[0111] The above content (1) and the above content (2) may be the same or different. The above content (1) and the above content (3) may be the same or different. From the perspective of enhancing the sound insulation property of the laminated glass, it is preferable that the above content (1) and the above content (2) are the same, or the above content (1) is less than the above content (2), and it is more preferable that the above content (1) is less than the above content (2). From the perspective of enhancing the sound insulation property of the laminated glass, it is preferable that the above content (1) and the above content (3) are the same, or the above content (1) is less than the above content (3), and it is more preferable that the above content (1) is less than the above content (3).

[0112] From the perspective of further enhancing the sound insulation property of the laminated glass, the absolute value of the difference between the above content (2) and the above content (1), and the absolute value of the difference between the above content (3) and the above content (1) are each preferably 10 parts by weight or more, more preferably 15 parts by weight or more, and still more preferably 20 parts by weight or more. The absolute value of the difference between the above content (2) and the above content (1), and the absolute value of the difference between the above content (3) and the above content (1) are each preferably 80 parts by weight or less, more preferably 75 parts by weight or less, and still more preferably 70 parts by weight or less.

[0113] (Heat-insulating substance) The above intermediate film preferably contains a heat-insulating substance. The above first layer (including a single-layer intermediate film) preferably contains a heat-insulating substance. The above second layer preferably contains a heat-insulating substance. The above third layer preferably contains a heat-insulating substance. Only one type of the above heat-insulating substance may be used, or two or more types may be used in combination.

[0114] The above heat-insulating substance preferably contains at least one component X among phthalocyanine compounds, naphthalocyanine compounds, and anthracyanine compounds, or contains heat-insulating particles. In this case, both the above component X and the above heat-insulating particles may be included.

[0115] Component X: The intermediate film preferably contains at least one component X among phthalocyanine compounds, naphthalocyanine compounds, and anthracyanine compounds. 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 component X is a heat-insulating substance. Only one kind of the component X may be used, or two or more kinds may be used in combination.

[0116] The component X is not particularly limited. As the component X, conventionally known phthalocyanine compounds, naphthalocyanine compounds, and anthracyanine compounds can be used.

[0117] Examples of the component X include phthalocyanine, derivatives of phthalocyanine, naphthalocyanine, derivatives of naphthalocyanine, anthracyanine, and derivatives of anthracyanine. Each of the phthalocyanine compound and the derivative of phthalocyanine preferably has a phthalocyanine skeleton. Each of the naphthalocyanine compound and the derivative of naphthalocyanine preferably has a naphthalocyanine skeleton. Each of the anthracyanine compound and the derivative of anthracyanine preferably has an anthracyanine skeleton.

[0118] From the viewpoint of further enhancing the heat insulation of the intermediate film and the laminated glass, the component X is preferably at least one selected from the group consisting of phthalocyanine, derivatives of phthalocyanine, naphthalocyanine, and derivatives of naphthalocyanine, and more preferably at least one of phthalocyanine and derivatives of phthalocyanine.

[0119] From the viewpoint of effectively enhancing the heat shielding property and maintaining the visible light transmittance at an even higher level over a long period, it is preferable that the above-mentioned component X contains vanadium atoms or copper atoms. It is preferable that the above-mentioned component X contains vanadium atoms, and it is also preferable that the above-mentioned component X contains copper atoms. More preferably, the above-mentioned component X is at least one of phthalocyanine containing vanadium atoms or copper atoms and derivatives of phthalocyanine containing vanadium atoms or copper atoms. From the viewpoint of further enhancing the heat shielding property of the intermediate film and the laminated glass, it is preferable that the above-mentioned component X has a structural unit in which an oxygen atom is bonded to a vanadium atom.

[0120] In 100% by weight of the above-mentioned intermediate film or in 100% by weight of the layer containing the above-mentioned component X (the first layer, the second layer or the third layer), the content of the above-mentioned component X is preferably 0.001% by weight or more, more preferably 0.005% by weight or more, still more preferably 0.01% by weight or more, and particularly preferably 0.02% by weight or more. In 100% by weight of the above-mentioned intermediate film or in 100% by weight of the layer containing the above-mentioned component X (the first layer, the second layer or the third layer), the content of the above-mentioned component X is preferably 0.2% by weight or less, more preferably 0.1% by weight or less, still more preferably 0.05% by weight or less, and particularly preferably 0.04% by weight or less. When the content of the above-mentioned component X is not less than the above lower limit and not more than the above upper limit, the heat shielding property becomes sufficiently high and the visible light transmittance becomes sufficiently high. For example, it is possible to make the visible light transmittance 70% or more.

[0121] Heat shielding particles: It is preferable that the above-mentioned intermediate film contains heat shielding particles. It is preferable that the above-mentioned first layer contains the above-mentioned heat shielding particles. It is preferable that the above-mentioned second layer contains the above-mentioned heat shielding particles. It is preferable that the above-mentioned third layer contains the above-mentioned heat shielding particles. The above-mentioned heat shielding particles are heat shielding substances. By using the heat shielding particles, infrared rays (heat rays) can be effectively blocked. Only one kind of the above-mentioned heat shielding particles may be used, or two or more kinds may be used in combination.

[0122] From the viewpoint of further enhancing the heat insulation property of the laminated glass, it is more preferable that the heat insulating particles are metal oxide particles. The heat insulating particles are preferably particles formed of a metal oxide (metal oxide particles).

[0123] 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, 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 heat insulating particles, infrared rays (heat rays) can be effectively blocked. Note that the heat insulating particles mean particles capable of absorbing infrared rays.

[0124] Specific examples of the heat insulating 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, silicon-doped zinc oxide particles, and lanthanum hexaboride (LaB6) particles. Heat insulating particles other than these may also be used. Since they have a high heat ray shielding function, metal oxide particles are preferable, ATO particles, GZO particles, IZO particles, ITO particles or tungsten oxide particles are more preferable, and ITO particles or tungsten oxide particles are particularly preferable. In particular, since they have a high heat ray shielding function and are easily available, tin-doped indium oxide particles (ITO particles) are preferable, and tungsten oxide particles are also preferable.

[0125] From the perspective of further enhancing the heat insulation properties of the interlayer film and the laminated glass, the tungsten oxide particles are preferably metal-doped tungsten oxide particles. The above-mentioned "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, rubidium-doped tungsten oxide particles, and the like.

[0126] From the perspective of further enhancing the heat insulation properties of the interlayer film and the laminated glass, cesium-doped tungsten oxide particles are particularly preferred. From the perspective of further enhancing the heat insulation properties of the interlayer film and the laminated glass, the cesium-doped tungsten oxide particles are preferably tungsten oxide particles represented by the formula: Cs 0.33 WO3.

[0127] The average particle diameter of the above heat insulation 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. When the average particle diameter is at least the above lower limit, the shielding property of the heat rays becomes sufficiently high. When the average particle diameter is at most the above upper limit, the dispersibility of the heat insulation particles becomes high.

[0128] The above-mentioned "average particle diameter" indicates the volume average particle diameter. The average particle diameter can be measured using a particle size distribution measuring device (such as "UPA-EX150" manufactured by Nikkiso Co., Ltd.).

[0129] In 100% by weight of the above intermediate film 100 or in 100% by weight of the layer containing the heat shielding particles (the first layer, the second layer or the third layer), the content of each of the heat shielding particles (particularly the content of tungsten oxide particles) is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, still more preferably 1% by weight or more, particularly preferably 1.5% by weight or more. In 100% by weight of the above intermediate film 100 or in 100% by weight of the layer containing the heat shielding particles (the first layer, the second layer or the third layer), the content of each of the heat shielding particles (particularly the content of tungsten oxide particles) is preferably 6% by weight or less, more preferably 5.5% by weight or less, still more preferably 4% by weight or less, particularly preferably 3.5% by weight or less, and most preferably 3% by weight or less. When the content of the heat shielding particles is not less than the above lower limit and not more than the above upper limit, the heat shielding property becomes sufficiently high and the visible light transmittance becomes sufficiently high.

[0130] (metal salt) The above intermediate film preferably contains at least one metal salt (hereinafter sometimes referred to as metal salt M) selected from alkali metal salts, alkaline earth metal salts other than magnesium salts, and magnesium salts. Further, since magnesium is an alkaline earth metal, the above intermediate film preferably contains at least one metal salt M selected from alkali metal salts and alkaline earth metal salts. The above first layer preferably contains the above metal salt M. The above second layer preferably contains the above metal salt M. The above third layer preferably contains the above metal salt M. Note that the alkaline earth metals mean six metals: Be, Mg, Ca, Sr, Ba, and Ra. By using the above metal salt M, it becomes easy to control the adhesiveness between the intermediate film and a laminated glass member such as a glass plate or the adhesiveness between the layers in the intermediate film. Only one kind of the above metal salt M may be used, or two or more kinds may be used in combination.

[0131] The above metal salt M 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 intermediate film preferably contains at least one metal selected from K and Mg.

[0132] Further, the metal salt M is more preferably an alkaline earth metal salt of an organic acid having 2 to 16 carbon atoms other than an alkali metal salt of an organic acid having 2 to 16 carbon atoms or a magnesium salt of an organic acid having 2 to 16 carbon atoms, or a magnesium salt of an organic acid having 2 to 16 carbon atoms. Further, since magnesium is an alkaline earth metal, the metal salt M is preferably 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 M is more preferably a magnesium carboxylate having 2 to 16 carbon atoms or a potassium carboxylate having 2 to 16 carbon atoms.

[0133] Examples of the magnesium carboxylate having 2 to 16 carbon atoms and the potassium carboxylate 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.

[0134] The total content of Mg and K in the intermediate film containing the metal salt M or the layer (the first layer, the second layer, or the third layer) containing the metal salt M is preferably 5 ppm or more, more preferably 10 ppm or more, still more preferably 20 ppm or more, and preferably 300 ppm or less, more preferably 250 ppm or less, still more preferably 200 ppm or less. When the total content of Mg and K is equal to or higher than the above lower limit and equal to or lower than the above upper limit, the adhesiveness between the intermediate film and the laminated glass member (such as a glass plate) or the adhesiveness between the layers in the intermediate film can be controlled even better.

[0135] (UV blocker) The intermediate film preferably contains a UV blocker. The first layer preferably contains a UV blocker. The second layer preferably contains a UV blocker. The third layer preferably contains a UV blocker. By using a UV blocker, even when the intermediate film and the laminated glass are used for a long time, the visible light transmittance is less likely to decrease further. Only one type of the UV blocker may be used, or two or more types may be used in combination.

[0136] The above ultraviolet ray blocking agent contains an ultraviolet ray absorber. The above ultraviolet ray blocking agent is preferably an ultraviolet ray absorber.

[0137] Examples of the above ultraviolet ray blocking agent include an ultraviolet ray blocking agent containing a metal atom, an ultraviolet ray blocking agent containing a metal oxide, an ultraviolet ray blocking agent having a benzotriazole structure (benzotriazole compound), an ultraviolet ray blocking agent having a benzophenone structure (benzophenone compound), an ultraviolet ray blocking agent having a triazine structure (triazine compound), an ultraviolet ray blocking agent having a malonic ester structure (malonic ester compound), an ultraviolet ray blocking agent having a oxalic acid anilide structure (oxalic acid anilide compound), and an ultraviolet ray blocking agent having a benzoate structure (benzoate compound), etc.

[0138] Examples of the above ultraviolet ray blocking agent containing a metal atom include platinum particles, particles with the surface of platinum particles coated with silica, palladium particles, and particles with the surface of palladium particles coated with silica, etc. The ultraviolet ray blocking agent is preferably not a heat insulating particle.

[0139] The above ultraviolet ray blocking agent is preferably an ultraviolet ray blocking agent having a benzotriazole structure, an ultraviolet ray blocking agent having a benzophenone structure, an ultraviolet ray blocking agent having a triazine structure, or an ultraviolet ray blocking agent having a benzoate structure. The above ultraviolet ray blocking agent is more preferably an ultraviolet ray blocking agent having a benzotriazole structure or an ultraviolet ray blocking agent having a benzophenone structure, and even more preferably an ultraviolet ray blocking agent having a benzotriazole structure.

[0140] Examples of the above ultraviolet ray blocking agent containing a metal oxide include zinc oxide, titanium oxide, cerium oxide, etc. Further, regarding the above ultraviolet ray blocking agent containing a metal oxide, the surface may be coated. Examples of the coating material on the surface of the above ultraviolet ray blocking agent containing a metal oxide include insulating metal oxides, hydrolyzable organosilicon compounds, and silicone compounds, etc.

[0141] Examples of the insulating metal oxide include silica, alumina, and zirconia. The insulating metal oxide has a band gap energy of, for example, 5.0 eV or more.

[0142] Examples of the ultraviolet absorber having the benzotriazole structure include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole ("Tinuvin P" manufactured by BASF), 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole ("Tinuvin 320" manufactured by BASF), 2-(2'-hydroxy-3'-t-butyl-5-methylphenyl)-5-chlorobenzotriazole ("Tinuvin 326" manufactured by BASF), and 2-(2'-hydroxy-3',5'-di-amylphenyl)benzotriazole ("Tinuvin 328" manufactured by BASF). Since it has excellent performance in shielding ultraviolet rays, the ultraviolet absorber is preferably an ultraviolet absorber having a benzotriazole structure containing a halogen atom, and more preferably an ultraviolet absorber having a benzotriazole structure containing a chlorine atom.

[0143] Examples of the ultraviolet absorber having the benzophenone structure include octabenzone ("Chimassorb 81" manufactured by BASF).

[0144] Examples of the ultraviolet absorber having the 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).

[0145] Examples of the ultraviolet absorber having the malonic ester structure include dimethyl 2-(p-methoxybenzylidene)malonate, tetraethyl 2,2-(1,4-phenylenedimethylene)bismalonate, and 2-(p-methoxybenzylidene)-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)malonate.

[0146] Examples of commercially available ultraviolet absorbers having the above-mentioned malonic ester structure include Hostavin B-CAP, Hostavin PR-25, and Hostavin PR-31 (all manufactured by Clariant).

[0147] Examples of ultraviolet absorbers having the above-mentioned oxalic acid anilide structure include oxalic acid diamides having an aryl group substituted on the nitrogen atom, such as N-(2-ethylphenyl)-N'-(2-ethoxy-5-t-butylphenyl)oxalic acid diamide, N-(2-ethylphenyl)-N'-(2-ethoxyphenyl)oxalic acid diamide, and 2-ethyl-2'-ethoxy-oxalanilide ("Sanduvor VSU" manufactured by Clariant).

[0148] Examples of ultraviolet absorbers having the above-mentioned benzoate structure include, for example, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate ("Tinuvin 120" manufactured by BASF).

[0149] In 100% by weight of the above intermediate film or in 100% by weight of the layer containing the above ultraviolet absorber (the first layer, the second layer, or the third layer), the content of the above ultraviolet absorber and the content of the benzotriazole compound are preferably 0.1% by weight or more, more preferably 0.2% by weight or more, still more preferably 0.3% by weight or more, and particularly preferably 0.5% by weight or more. In 100% by weight of the above intermediate film or in 100% by weight of the layer containing the above ultraviolet absorber (the first layer, the second layer, or the third layer), the content of the above ultraviolet absorber and the content of the benzotriazole compound are preferably 2.5% by weight or less, more preferably 2% by weight or less, still more preferably 1% by weight or less, and particularly preferably 0.8% by weight or less. When the content of the above ultraviolet absorber is not less than the above lower limit and not more than the above upper limit, the decrease in the visible light transmittance after the passage of time can be further suppressed. In particular, when the content of the above ultraviolet absorber in 100% by weight of the layer containing the above ultraviolet absorber is 0.2% by weight or more, the decrease in the visible light transmittance of the intermediate film and the laminated glass after the passage of time can be significantly suppressed.

[0150] (Antioxidant) The intermediate 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. Only one kind of the antioxidant may be used, or two or more kinds may be used in combination.

[0151] Examples of the antioxidant include phenolic antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants. The phenolic antioxidant is an antioxidant having a phenol skeleton. The sulfur-based antioxidant is an antioxidant containing a sulfur atom. The phosphorus-based antioxidant is an antioxidant containing a phosphorus atom.

[0152] The antioxidant is preferably a phenolic antioxidant or a phosphorus-based antioxidant.

[0153] 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-t-butylphenyl)butane, tetrakis[methylene-3-(3',5'-butyl-4-hydroxyphenyl)propionate]methane, 1,3,3-tris-(2-methyl-4-hydroxy-5-t-butylphenyl)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-methylbenzene propanoic acid)ethylene bis(oxyethylene). One kind or two or more kinds of these antioxidants are preferably used.

[0154] Examples of the phosphorus-based antioxidants 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.

[0155] Examples of commercially available products of the above 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, etc.

[0156] In order to maintain the high visible light transmittance of the intermediate film and the laminated glass over a long period of time, the content of the above antioxidant is preferably 0.1% by weight or more in 100% by weight of the above intermediate film or in 100% by weight of the layer containing the antioxidant (the first layer, the second layer, or the third layer). Also, since the addition effect of the antioxidant saturates, the content of the above antioxidant is preferably 2% by weight or less in 100% by weight of the above intermediate film or in 100% by weight of the layer containing the antioxidant.

[0157] (Other components) The above intermediate film, the first layer, the second layer, and the third layer may each contain additives such as a coupling agent, a dispersant, a surfactant, a flame retardant, an antistatic agent, a pigment, a dye, an adhesion adjuster other than a metal salt, a moisture resistant agent, a fluorescent brightening agent, and an infrared absorber, etc., as required. These additives may be used alone or in combination of two or more.

[0158] (Functional film) The above intermediate film may be provided with a functional film for the purpose of expressing a specific function. Examples of the above functional film include a dimming film, an infrared reflection film, a coloring film, and a film with a printed design.

[0159] Examples of the above dimming film include a film having an electrochromic layer and an electrolyte layer. The above electrochromic layer is a layer containing an electrochromic compound (a compound having electrochromic properties). Note that having electrochromic properties means having the property that the light transmittance changes by applying a voltage.

[0160] Examples of the above infrared reflection film include a resin film with a metal foil, a multilayer laminated film in which a metal layer and a dielectric layer are formed on a resin film, a multilayer resin film, and a liquid crystal film. These films have the performance of reflecting infrared rays.

[0161] The above resin film with a metal foil includes a resin film and a metal foil laminated on the outer surface of the resin film. Examples of the material of the above resin film include polyethylene terephthalate resin, polyethylene naphthalate resin, polyvinyl acetal resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, polyurethane resin, polyvinyl alcohol resin, polyolefin resin, polyvinyl chloride resin, and polyimide resin. Examples of the material of the above metal foil include aluminum, copper, silver, gold, palladium, and alloys containing these.

[0162] The above multilayer laminated film in which a metal layer and a dielectric layer are formed on the resin film is a multilayer laminated film in which the metal layer and the dielectric layer are alternately laminated in an arbitrary number of layers on the resin film. Note that in the above multilayer laminated film in which a metal layer and a dielectric layer are formed on the resin layer, it is preferable that all of the metal layer and the dielectric layer are alternately laminated, but there may be a structural 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.

[0163] Examples of the material of the resin film in the multilayer laminated film include polyethylene, polypropylene, polylactic acid, poly(4-methylpentene-1), polyvinylidene fluoride, cyclic polyolefin, polymethyl methacrylate, polyvinyl chloride, polyvinyl alcohol, polyamides such as nylon 6, 11, 12, 66, polystyrene, polycarbonate, polyethylene terephthalate, polyethylene naphthalate, polyester, polyphenylene sulfide, and polyetherimide. Examples of the material of the metal layer in the multilayer laminated film include the same materials as those of the metal foil in the resin film with a metal foil. A coat layer of a metal or a mixed oxide of a metal can be provided on both sides or one side of the metal layer. Examples of the material of the coat layer include ZnO, Al2O3, Ga2O3, InO3, MgO, Ti, NiCr, and Cu. In addition, examples of the material of the dielectric layer in the multilayer laminated film include indium oxide.

[0164] The multilayer resin film is a laminated film in which a plurality of resin films are laminated. Examples of the material of the multilayer resin film include the same materials as those of the resin film in the multilayer laminated film. The number of resin films laminated in the multilayer resin film is 2 or more, may be 3 or more, and may be 5 or more. The number of resin films laminated in the multilayer resin film may be 1000 or less, may be 100 or less, and may be 50 or less.

[0165] The multilayer resin film may be a multilayer resin film in which two or more thermoplastic resin layers having different optical properties (refractive index) are laminated in any number of layers alternately or randomly. Such a multilayer resin film is configured to obtain desired infrared reflection performance.

[0166] Examples of the liquid crystal film include films in which cholesteric liquid crystal layers that reflect light of any wavelength are stacked in any number of layers. Such a liquid crystal film is configured to obtain desired infrared reflection performance.

[0167] The infrared reflection film may contain infrared reflective particles. The infrared reflective particles are particles having infrared reflection performance, and examples thereof include flat plate particles having a thickness of 1 nm or more and 1000 μm or less. For example, in a resin film in which silver nanoplates are dispersed, an infrared reflection film having infrared reflection performance can be obtained by adjusting the thickness, surface area, and arrangement state of the silver nanoplates.

[0168] Since it has excellent performance in reflecting infrared rays, it is preferable that the functional film has a property that the infrared transmittance is 40% or less at at least one wavelength in the range of 800 nm to 2000 nm. At at least one wavelength in the range of 800 nm to 2000 nm, the infrared transmittance is more preferably 30% or less, and still more preferably 20% or less.

[0169] Specifically, the transmittance of each wavelength of the functional film in the wavelength range of 800 nm to 2000 nm is measured as follows. Prepare a single functional film. Using a spectrophotometer ("U-4100" manufactured by Hitachi High-Technologies Corporation), obtain the spectral transmittance of each wavelength of the functional film in the wavelength range of 800 nm to 2000 nm in accordance with JIS R3106:1998.

[0170] (Other details of the interlayer film for laminated glass) The interlayer film is preferably used to obtain laminated glass without performing autoclave treatment. However, the interlayer film may be used to obtain laminated glass by performing autoclave treatment.

[0171] The thickness of the above intermediate film is not particularly limited. From the perspective of practicality and from the perspective of sufficiently enhancing the penetration resistance and bending rigidity of the laminated glass, the thickness of the above intermediate 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 of the above intermediate film is equal to or greater than the above lower limit, the penetration resistance and bending rigidity of the laminated glass will be even higher. When the thickness of the above intermediate film is equal to or less than the above upper limit, the transparency of the intermediate film and the laminated glass will be even better.

[0172] Let the thickness of the intermediate film be T. The thickness of each of the above first layer, the above first surface layer, and the above second surface layer is preferably 0.005T or more, more preferably 0.01T or more, still more preferably 0.02T or more, preferably 0.17T or less, more preferably 0.15T or less, more preferably 0.13T or less, more preferably 0.1T or less, and still more preferably 0.09T or less. When the above thickness is equal to or greater than the above lower limit and equal to or less than the above upper limit, the sound insulation performance will be even higher over a wide temperature range.

[0173] The above intermediate film may be an intermediate film with a uniform thickness or an intermediate film with a varying thickness. The cross-sectional shape of the above intermediate film may be rectangular or wedge-shaped.

[0174] The intermediate film may be wound into a roll body of the intermediate film. The roll body may include a winding core and the intermediate film wound around the outer periphery of the winding core.

[0175] The distance between one end and the other end of the above intermediate film is preferably 3 m or less, more preferably 2 m or less, particularly preferably 1.5 m or less, preferably 0.5 m or more, more preferably 0.8 m or more, and particularly preferably 1 m or more. When the intermediate film has a length direction and a width direction, the distance between one end and the other end is the distance in the length direction of the intermediate film. When the intermediate film has a square planar shape, the distance between one end and the other end is the distance between the opposed one end and the other end.

[0176] The manufacturing method of the interlayer film according to the present invention is not particularly limited. As the manufacturing method of the interlayer film according to the present invention, in the case of a single-layer interlayer film, examples include a method of extruding a resin composition using an extruder and a method of hot press molding. As the manufacturing method of the interlayer film according to the present invention, in the case of a multi-layer interlayer film, for example, after forming each layer using each resin composition for forming each layer, a method of laminating the obtained layers, and a method of laminating each layer by co-extruding each resin composition for forming each layer using an extruder, etc. can be mentioned.

[0177] Since the manufacturing efficiency of the interlayer film is excellent, it is preferable that the same polyvinyl acetal resin is contained in the first surface layer and the second surface layer. Since the manufacturing efficiency of the interlayer film is excellent, it is more preferable that the same polyvinyl acetal resin and the same plasticizer are contained in the first surface layer and the second surface layer. Since the manufacturing efficiency of the interlayer film is excellent, it is even more preferable that the first surface layer and the second surface layer are formed of the same resin composition.

[0178] It is preferable that the above-mentioned interlayer film has an uneven shape on at least one of the surfaces on both sides. It is more preferable that the interlayer film has an uneven shape on both surfaces. The method for forming the above-mentioned uneven shape is not particularly limited, and examples include a lip embossing method, an embossing roll method, a calendar roll method, and a profile extrusion method. Since a large number of uneven-shaped embossings with a quantitatively constant uneven pattern can be formed, the embossing roll method is preferable.

[0179] (Laminated glass) The laminated glass according to the present invention includes a first laminated glass member, a second laminated glass member, and the above-mentioned interlayer film for laminated glass. In the laminated glass according to the present invention, the above-mentioned interlayer film for laminated glass is disposed between the first laminated glass member and the second laminated glass member.

[0180] FIG. 4 is a cross-sectional view schematically showing an example of laminated glass using the interlayer film for laminated glass shown in FIG. 1.

[0181] The laminated glass 31 shown in Fig. 4 includes a first laminated glass member 21, a second laminated glass member 22, and an intermediate film 11. The intermediate film 11 is disposed between the first laminated glass member 21 and the second laminated glass member 22 and is sandwiched therebetween.

[0182] The first laminated glass member 21 is laminated on the first surface 11a of the intermediate film 11. The second laminated glass member 22 is laminated on the second surface 11b of the intermediate film 11, which is opposite to the first surface 11a.

[0183] Thus, the laminated glass according to the present invention includes a first laminated glass member, a second laminated glass member, and an intermediate film, and the intermediate film is an intermediate film for laminated glass according to the present invention. In the laminated glass according to the present invention, the intermediate film is disposed between the first laminated glass member and the second laminated glass member.

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

[0185] Examples of the first and second laminated glass members include a glass plate and a PET (polyethylene terephthalate) film. The laminated glass includes not only laminated glass in which an intermediate film is sandwiched between two glass plates, but also laminated glass in which an intermediate film is sandwiched between a glass plate and a PET film or the like. The laminated glass is a laminate including a glass plate, and it is preferable that at least one glass plate is used. 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 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.

[0186] Examples of the glass plate include inorganic glass and organic glass. Examples of the inorganic glass include float plate glass, heat ray absorbing plate glass, heat ray reflecting plate glass, polished plate glass, mold plate glass, wired plate glass, and green glass. The organic glass is a synthetic resin glass that substitutes for 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 polymethyl (meth)acrylate plates.

[0187] The thicknesses of the first laminated glass member and the second laminated glass member are preferably 1 mm or more, preferably 5 mm or less, and 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, preferably 5 mm or less, and 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.

[0188] The method for manufacturing the laminated glass preferably includes a step of disposing an intermediate film between the first laminated glass member and the second laminated glass member, and then bonding the first and second laminated glass members and the intermediate film to obtain a laminate. In this step, it is preferable to degas the air remaining between the first laminated glass member, the second laminated glass member, and the intermediate film by passing it through a pressing roll or placing it in a rubber bag and performing decompression suction. The temperature during bonding is, for example, 70°C to 100°C.

[0189] The above-mentioned intermediate film and the above-mentioned laminated glass can be used in automobiles, railway vehicles, aircraft, ships, buildings, and the like. The above-mentioned intermediate film and the above-mentioned laminated glass can also be used for other purposes. The above-mentioned intermediate film and the above-mentioned laminated glass are preferably an intermediate film and a laminated glass for vehicles or buildings, and more preferably an intermediate film and a laminated glass for vehicles. The above-mentioned intermediate film and the above-mentioned laminated glass can be used for the front glass, side glass, rear glass, roof glass, etc. of an automobile. The above-mentioned intermediate film and the above-mentioned laminated glass are preferably used for automobiles. The above-mentioned intermediate film is used to obtain laminated glass for automobiles.

[0190] The present invention will be described in more detail below with reference to Examples and Comparative Examples. The present invention is not limited only to these Examples.

[0191] In the polyvinyl acetal resin used, n-butyl aldehyde having 4 carbon atoms is used for acetalization. Regarding the polyvinyl acetal resin, the degree of acetalization (degree of butyralization), the degree of acetylation, and the hydroxyl group content were measured by a method conforming to JIS K6728 "Test Method for Polyvinyl Butyral". In addition, when measured by ASTM D1396-92, the same numerical values as those of the method conforming to JIS K6728 "Test Method for Polyvinyl Butyral" were shown.

[0192] The following materials were prepared.

[0193] (Polyvinyl acetal resin) Polyvinyl acetal resin (polyvinyl butyral resin (PVB1), average degree of polymerization 1700, hydroxyl group content 30.4 mol%, degree of acetylation 1.0 mol%, degree of acetalization (degree of butyralization) 68.6 mol%) Polyvinyl acetal resin (polyvinyl butyral resin (PVB2), average degree of polymerization 850, hydroxyl group content 31.0 mol%, degree of acetylation 1.0 mol%, degree of acetalization (degree of butyralization) 68.0 mol%) Polyvinyl acetal resin (polyvinyl butyral resin (PVB3), average degree of polymerization 1500, hydroxyl group content 30.8 mol%, degree of acetylation 0.5 mol%, degree of acetalization (butyralization degree) 68.7 mol%)

[0194] (Plasticizer) Triethylene glycol di-2-ethylhexanoate (3GO)

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

[0196] (UV absorber) Tinuvin326 (2-(2’-hydroxy-3’-t-butyl-5-methylphenyl)-5-chlorobenzotriazole, "Tinuvin326" manufactured by BASF)

[0197] (Antioxidant) BHT (2,6-di-t-butyl-p-cresol)

[0198] (Example 1) Preparation of a composition for forming an intermediate film (first layer): The following components were blended and kneaded thoroughly with a mixing roll to obtain a composition for forming an intermediate film (first layer).

[0199] 37.5 parts by weight of polyvinyl butyral resin (PVB1) 62.5 parts by weight of polyvinyl butyral resin (PVB2) 30 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) An amount of metal salt M (Mg mixture) that becomes 70 ppm in the resulting intermediate film An amount of UV absorber (Tinuvin326) that becomes 0.2% by weight in the resulting intermediate film An amount of antioxidant (BHT) that becomes 0.2% by weight in the resulting intermediate film

[0200] Preparation of the intermediate film: A composition for forming an intermediate film (first layer) was hot press-molded to produce a single-layer intermediate film (thickness: 0.8 mm) having only the first layer.

[0201] (Examples 2 to 5 and Comparative Examples 1 to 4) A single-layer intermediate film (thickness: 0.8 mm) was produced in the same manner as in Example 1, except that the type and content of the resin and the content of the plasticizer were changed as shown in Tables 1 and 2.

[0202] (Evaluation) (1) Glass transition temperature and softening point of the first layer The obtained first layer was stored for 12 hours in an environment at room temperature of 23 ± 2°C and humidity of 25 ± 5%. Then, viscoelasticity was measured using a viscoelasticity measuring device "ARES-G2" manufactured by TA Instruments. A parallel plate with a diameter of 8 mm was used as a jig, and the measurement was performed under the conditions of a shear mode, a temperature decrease rate of 3°C / min from 100°C to -20°C, and conditions of a frequency of 1 Hz and a strain of 1%. In the obtained measurement results, the peak temperature of the loss tangent was defined as the glass transition temperature Tg (°C). The temperature at which the value of the loss tangent becomes minimum in the temperature range between Tg (°C) and 100°C was defined as the softening point.

[0203] (2) Weight average molecular weight and number average molecular weight of the resin contained in the first layer The obtained first layer was dissolved in N-methylpyrrolidone to prepare a 0.2 wt% solution, and the solution was filtered through a 0.45 μm filter. This N-methylpyrrolidone was used with a sample in which lithium bromide was dissolved at a concentration of 10 mmol / ml. Subsequently, the number average molecular weight and weight average molecular weight of the polyvinyl acetal resin in terms of polystyrene were measured using a gel permeation chromatography apparatus ("Shodex GPC-101", detector: RI-71S, autosampler: AS101, guard column: KF-G, two columns of LF-804 in series). The measurement was carried out under the conditions of a flow rate of 0.5 ml / ml and a column temperature of 40°C. As standard samples ("Shodex Standard SM-105"), 10 samples with the following weight average molecular weights were used. The sample No (weight average molecular weight) is as follows: S-1.3 (1,270), S-3.2 (3,180), S-6.9 (6,940), S-22 (21,800), S-53 (52,500), S-139 (139,000), S-333 (333,000), S-609 (609,000), S-1345 (1,350,000), S-2704 (2,700,000). The molecular weights were plotted against the elution times indicated by the peak tops of the respective standard sample peaks, and the obtained approximate straight line was used as a calibration curve.

[0204] (3) Compression creep test The obtained first layer (intermediate film) was cut out into a diameter of 8 mm to obtain test samples. Using the obtained test samples, a compression creep test was carried out by the method described above. Since the thickness of the first layer (intermediate film) was 0.8 mm, the obtained test samples corresponded to test samples A, B, and C. Also, the thickness of the test samples after the compression creep test was smaller than the thickness of the test samples before the compression creep test.

[0205] (4) Falling ball test (penetration resistance) Two glass plates (clear float glass) with a length of 30 cm, a width of 30 cm, and a thickness of 2.5 mm were prepared. The obtained intermediate film was sandwiched between these two glass plates to obtain a laminate. The obtained laminate was placed in a rubber bag and degassed at a vacuum degree of 2660 Pa (20 torr) for 20 minutes. Then, while maintaining the degassed state, the laminate was heated to 90 °C at a heating rate of 4 °C / min, held at 90 °C for 5 minutes, and then cooled to 30 °C. Subsequently, the pressure was returned to normal pressure. In this way, laminated glass was obtained.

[0206] For the obtained laminated glass, an iron ball with a diameter of 82 mm and a weight of 2260 g was dropped from a height of 4 m at a position 150 mm inside from the end of the laminated glass.

[0207] [Judgment Criteria for Falling Ball Test (Penetration Resistance)] Pass: After the falling ball test, the iron ball is kept in a state of being held on the laminated glass. Fail: After the falling ball test, the iron ball penetrates the laminated glass and falls.

[0208] (5) Foaming at the Edge of Laminated Glass (Edge Foaming) Two glass plates (clear float glass) with a length of 10 cm, a width of 10 cm, and a thickness of 2.5 mm were prepared. The obtained intermediate film was sandwiched between these two glass plates to obtain a laminate. The obtained laminate was placed in a rubber bag and degassed at a vacuum degree of 2660 Pa (20 torr) for 20 minutes. Then, while maintaining the degassed state, the laminate was heated to 90 °C at a heating rate of 4 °C / min, held at 90 °C for 5 minutes, and then cooled to 30 °C. Subsequently, the pressure was returned to normal pressure. In this way, laminated glass was obtained.

[0209] The obtained laminated glass was placed still on a dark curtain, and the edge of the laminated glass was visually observed, and the foaming ratio was evaluated in 5 levels from level 1 to level 5. At level 1, no foaming was observed, and as it goes to level 5, the foamed part was observed.

[0210] Examples of captured images determined to be level 1 are shown in Fig. 5(a), examples of captured images determined to be level 2 are shown in Fig. 5(b), examples of captured images determined to be level 3 are shown in Fig. 5(c), examples of captured images determined to be level 4 are shown in Fig. 5(d), and examples of captured images determined to be level 5 are shown in Fig. 5(e).

[0211] (6) Transparency of laminated glass Two glass plates (clear float glass) with dimensions of 30 cm in length × 30 cm in width × 2.5 mm in thickness were prepared. The obtained intermediate film was sandwiched between these two glass plates to obtain a laminate. The obtained laminate was placed in a rubber bag and degassed at a vacuum degree of 2660 Pa (20 torr) for 20 minutes. Then, while maintaining the degassed state, the laminate was heated to 95°C at a heating rate of 6°C / min, held at 95°C for 20 minutes, and then cooled to 30°C. Subsequently, the pressure was returned to normal pressure. In this way, laminated glass was obtained.

[0212] The obtained laminated glass was placed stationary on a dark screen, and the transparency of the laminated glass was visually observed, and the transparency level was evaluated in five levels from 1 to 5. At level 1, the entire surface is completely transparent, and as it approaches level 5, portions with lower transparency are observed.

[0213] Examples of captured images determined to be level 1 are shown in Fig. 6(a), examples of captured images determined to be level 2 are shown in Fig. 6(b), examples of captured images determined to be level 3 are shown in Fig. 6(c), examples of captured images determined to be level 4 are shown in Fig. 6(d), and examples of captured images determined to be level 5 are shown in Fig. 6(e).

[0214] Details and results are shown in Tables 1 and 2 below. Note that in the tables, the descriptions of metal salt M, ultraviolet absorber, and antioxidant are omitted.

[0215]

Table 1

[0216]

Table 2

Description of Symbols

[0217] 1,1B…First surface layer 2,2B…Second surface layer 3…Intermediate layer 3B…First intermediate layer 4B…Second intermediate layer 5B…Third intermediate layer 1a,1Ba,2a,2Ba…First surface 11,11B…Intermediate film 11A…Intermediate film (first layer) 11a…First surface 11b…Second surface 21…First laminated glass member 22…Second laminated glass member 31…Laminated glass

Claims

1. An interlayer film for laminated glass having a one-layer structure or a two or more layer structure, A first layer having a thickness of 200 μm or more and 900 μm or less, The thickness of the first layer is T Ｂ The diameter and thickness of the first layer cut out are 8 mm and T Ｂ When a compressive creep test is performed on a test sample B having a thickness of 100 μm or more, the change in thickness of the test sample B before and after the compressive creep test is 50 μm or more and 325 μm or less. Compression creep test: With a load of 410 g applied to test sample B, the temperature is raised from 30° C. to 90° C. at a rate of 6° C. / min, and the test sample is held at 90° C. for 5 minutes. The absolute value of the difference between the thickness of test sample B at 30° C. immediately after holding at 30° C. for 30 minutes before starting the compression creep test and the thickness of test sample B immediately after holding at 90° C. for 5 minutes at the end of the compression creep test is defined as the change in thickness of test sample B before and after the compression creep test.

2. An interlayer film for laminated glass having a one-layer structure or a two or more layer structure, A first layer, The thickness of the intermediate film is 80 μm or more and 1600 μm or less, The thickness of the intermediate film is T Ｃ The intermediate film is cut out to have a diameter of 8 mm and a thickness of T Ｃ When a compressive creep test is performed on a test sample C having a thickness of 100 μm or more, the change in thickness of the test sample C before and after the compressive creep test is 50 μm or more and 325 μm or less. Compression creep test: With a load of 410 g applied to the test sample C, the temperature is raised from 30° C. to 90° C. at a rate of 6° C. / min, and the test sample is held at 90° C. for 5 minutes. The absolute value of the difference between the thickness of the test sample C at 30° C. at the start of the compression creep test and the thickness of the test sample C immediately after being held at 90° C. for 5 minutes at the end of the compression creep test is defined as the change in thickness of the test sample C before and after the compression creep test.

3. The interlayer film for laminated glass according to claim 1 or 2, wherein the first layer comprises a thermoplastic resin and a plasticizer.

4. The interlayer film for laminated glass according to claim 3 , wherein the thermoplastic resin contained in the first layer is a polyvinyl acetal resin.

5. It has a structure of two or more layers, Further comprising a second layer, The interlayer film for laminated glass according to any one of claims 1 to 4, wherein the second layer is disposed on a first surface side of the first layer.

6. The interlayer film for laminated glass according to any one of claims 1 to 5, wherein the first layer is a surface layer in the interlayer film.

7. a first laminated glass member; a second laminated glass member; and The interlayer film for laminated glass according to any one of claims 1 to 6, The laminated glass, wherein the interlayer film for laminated glass is disposed between the first laminated glass member and the second laminated glass member.

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