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

Abstract

The interlayer film for laminated glass (1) according to the present invention comprises a functional film (10) and one or more first polymer sheets (20a, 20b) provided on one surface (11) of the functional film (10). In a projected view in the thickness direction, the functional film (10) is included at least in a region of the first polymer sheet (20a) among the one or more first polymer sheets (20a, 20b) that contacts the functional film. One or more gap filler polymer sheets (30) are further comprised provided to the opposite side from the functional film side of the first polymer sheet(s) (20a, 20b). The laminated glass according to the present invention comprises a pair of glass plates, and the interlayer film for laminated glass 1 provided between the pair of glass plates. According to the present invention, it is possible to provide an interlayer film for laminated glass that can reduce the size of a gap occurring at an end of a functional film while also preventing the occurrence of a level difference in the thickness direction, laminated glass, and a production method for an interlayer film for laminated glass.

Description

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

[0001] The present invention relates to an interlayer film for laminated glass, laminated glass, and a method for producing an interlayer film for laminated glass.

[0002] Conventionally, laminated glass, which is formed by interposing an interlayer film between two glass sheets and integrating them, has been widely known. The interlayer film is often formed from plasticized polyvinyl acetal, which is a polyvinyl acetal resin blended with a plasticizer. Laminated glass is safe because it hardly shatters glass fragments even if it is broken by external impact, and is therefore widely used as window glass in vehicles such as automobiles, aircraft, buildings, etc.

[0003] Laminated glass is generally produced by placing an interlayer between two glass sheets, and after a preliminary degassing process, heating and pressurizing the glass and the interlayer in an autoclave (ACV) process at a temperature of about 130 to 140°C and a pressure of about 1.3 MPa to bond them together.

[0004] In recent years, laminated glass has been required to have various functions, for example, a functional film such as a photochromic film may be disposed between two glass sheets. When a functional film such as a photochromic film is incorporated into laminated glass, it is known that two films are prepared, and the functional film is sandwiched between the two films and integrated to be used as an interlayer film.

[0005] It is also known that an intermediate layer having an opening and an intermediate layer having no opening are prepared as intermediate layers constituting an interlayer film, and the glass plate and the intermediate layer are laminated to form a structure of glass plate / intermediate layer having no opening / intermediate layer with a functional film disposed inside the opening / intermediate layer having no opening / glass plate, thereby integrating the glass plate, the interlayer film, and the functional film (see, for example, Patent Document 1).

[0006] Special Publication No. 2009-534283

[0007] Interlayers obtained by sandwiching a functional film between two films generally have smaller dimensions than the individual films, resulting in a step between the areas where the functional film is provided and the areas where it is not, resulting in uneven thickness.

[0008] On the other hand, when an intermediate layer having an opening is used as in Patent Document 1, it is possible to suppress the occurrence of a step in the intermediate layer that occurs between an area where the functional film is present and an area where the functional film is not present, and it is possible to make the thickness uniform throughout the intermediate layer. However, when the glass plate, the intermediate layer, and the functional film are heated and pressed together using an autoclave or the like, the position of the intermediate layer having the opening may shift or the dimensions may change, which may cause the problem of voids occurring at the edges of the functional film.

[0009] Therefore, another object of the present invention is to provide an interlayer film for laminated glass, laminated glass, and a method for manufacturing an interlayer film for laminated glass that can reduce gaps that occur at the edges of a functional film while suppressing the occurrence of steps in the thickness direction.

[0010] As a result of extensive research, the present inventors have found that the above-mentioned problems can be solved by examining the positioning of a polymer sheet for a gap filler that suppresses the occurrence of a step in an interlayer film between an area where a functional film is present and an area where a functional film is not present, and have completed the present invention as described below. That is, the present invention provides the following [1] to

[18] .

[0011] [1] An interlayer film for laminated glass, comprising a functional film and one or more first polymer sheets provided on one side of the functional film, wherein, in a projection view in the thickness direction, the functional film is included in at least a region of the one or more first polymer sheets that is in contact with the functional film, and further comprising one or more polymer sheets for gap fillers provided on the side of the first polymer sheet opposite to the functional film side. [2] A surface roughness (R ｚｊｉｓ９４[3] The interlayer film for laminated glass according to the above [1] or [2], further comprising a second polymer sheet provided on the other side of the functional film. [4] The interlayer film for laminated glass according to the above [1] or [2], further comprising a second polymer sheet provided on the other side of the functional film. [5] The interlayer film for laminated glass according to the above [1] or [2], further comprising a second polymer sheet provided on the other side of the functional film. [6] The interlayer film for laminated glass according to the above [1] or [2], ｚｊｉｓ９４[5] The interlayer film for laminated glass according to [3] above, wherein, in a projection view in the thickness direction, the distance between the outer periphery of the first polymer sheet and the outer periphery of the polymer sheet for gap filler is 0 mm or more and 10 mm or less, in a projection view in the thickness direction, the distance between the outer periphery of the second polymer sheet and the outer periphery of the polymer sheet for gap filler is 0 mm or more and 10 mm or less, in a projection view in the thickness direction, and the distance between the outer periphery of the first polymer sheet and the outer periphery of the second polymer sheet is 0 mm or more and 10 mm or less, in a projection view in the thickness direction. [6] The interlayer film for laminated glass according to any one of [1] to [5] above, wherein the polymer sheet for gap filler has an opening in a region overlapping with the functional film in a projection view in the thickness direction. [7] The interlayer film for laminated glass according to [6] above, wherein the polymer sheet for gap filler having the opening is constituted by a plurality of polymer sheets arranged in a planar direction. [8] The interlayer film for laminated glass according to [6] or [7] above, wherein the distance between the inner periphery of the opening in the gap filler polymer sheet and the outer periphery of the functional film is 5 mm or less along the entire periphery when viewed in a projection view in the thickness direction. [9] The interlayer film for laminated glass according to any one of [1] to [8] above, wherein at least one of the first polymer sheet and the cap filler polymer sheet contains at least one thermoplastic resin selected from the group consisting of polyvinyl acetal resin and ethylene-vinyl acetate copolymer resin.

[10] The interlayer film for laminated glass according to any one of [1] to [9] above, wherein the functional film has the function of absorbing or reflecting specific light.

[11] The interlayer film for laminated glass according to any one of [1] to

[10] above, wherein the functional film contains a polyethylene terephthalate resin.

[12] The interlayer film for laminated glass according to any one of [1] to

[11] above, wherein the functional film is a P-polarized reflective film, a film for holograms, a heat ray reflective film, a light control film, a display element film, a transparent conductive film, a touch sensor film, a circuit film, a photovoltaic power generation film, or an electrically controllable film.

[13] The interlayer film for laminated glass according to any one of [3] to [5] above, wherein the second polymer sheet contains at least one thermoplastic resin selected from the group consisting of polyvinyl acetal resin and ethylene-vinyl acetate copolymer resin.

[14] The interlayer film for laminated glass according to any one of [1] to

[13] above, further comprising a third polymer sheet provided on the surface of the gap filler polymer sheet opposite to the first polymer sheet side.

[15] The interlayer film for laminated glass according to any one of [3] to [5] above, wherein the surface of the gap filler polymer sheet side and the surface of the second polymer sheet side have irregularities with a regular or random shape.

[16] The interlayer film for laminated glass according to any one of [3] to [5] above, wherein at least one of the surface of the gap filler polymer sheet side and the surface of the second polymer sheet side is protected by a protective release film.

[17] A method for producing an interlayer film for laminated glass according to any one of [1] to

[16] above, comprising a step of laminating a functional film, a first polymer sheet, and a polymer sheet for gap filler so that they are arranged in this order.

[18] A laminated glass comprising a pair of glass plates and the interlayer film for laminated glass according to any one of [1] to

[16] above, disposed between the pair of glass plates.

[0012] The present invention can provide an interlayer film for laminated glass, laminated glass, and a method for manufacturing an interlayer film for laminated glass that can reduce gaps that occur at the edges of a functional film while suppressing the occurrence of steps in the thickness direction.

[0013] FIG. 1( a) is a plan view of an interlayer film for laminated glass according to a first embodiment of the present invention, FIG. 1( b) is a cross-sectional view taken along line A-A of FIG. 1( a), and FIG. 1( c) is an exploded view of the interlayer film for laminated glass according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view of a modified interlayer film for laminated glass according to the first embodiment of the present invention. FIG. 3( a) is a plan view of an interlayer film for laminated glass according to a second embodiment of the present invention, FIG. 3( b) is a cross-sectional view taken along line A-A of FIG. 3( a), and FIG. 3( c) is an exploded view of the interlayer film for laminated glass according to the second embodiment of the present invention. FIG. 4 is a cross-sectional view of a modified interlayer film for laminated glass according to the second embodiment of the present invention. FIG. 5 is an exploded view of an interlayer film for laminated glass according to a third embodiment of the present invention. FIG. 6 is a cross-sectional view of a modified interlayer film for laminated glass according to the third embodiment of the present invention. FIG. 7 is an exploded view of an interlayer film for laminated glass according to a fourth embodiment of the present invention. FIG. 8 is a cross-sectional view of a modified interlayer film for laminated glass according to the fourth embodiment of the present invention. FIG. 9 is a cross-sectional view of an interlayer film for laminated glass according to a fifth embodiment of the present invention. FIG. 10 is a cross-sectional view of a modified example of the interlayer film for laminated glass according to the fifth embodiment of the present invention. FIG. 11 is a cross-sectional view of laminated glass showing an example of the layer structure of the laminated glass of the present invention. FIG. 12 is a cross-sectional view of laminated glass showing an example of the layer structure of the laminated glass of the present invention. FIG. 13 is a diagram illustrating the measurement of the thickness of the interlayer film for laminated glass in the Examples. FIG. 14(a) is a diagram illustrating the structure of the interlayer film for laminated glass of Examples 1, 2, 4, and 5, FIG. 14(b) is a diagram illustrating the structure of the interlayer film for laminated glass of Example 3, and FIG. 14(c) is a diagram illustrating the structure of the interlayer film for laminated glass of Example 6. FIG. 14(d) is a diagram illustrating the structure of the interlayer film for laminated glass of Comparative Example 1, and FIG. 14(e) is a diagram illustrating the structure of the interlayer film for laminated glass of Comparative Example 2. FIG. 15(a) is a diagram illustrating the polymer sheet for gap filler in the interlayer film for laminated glass of Examples 1 and 3 and Comparative Example 2, and FIG. 15(b) is a diagram illustrating the polymer sheet for gap filler in the interlayer film for laminated glass of Example 2.Fig. 16(a) is a plan view of an interlayer film for laminated glass according to a sixth embodiment of the present invention, Fig. 16(b) is a cross-sectional view taken along line A-A in Fig. 16(a), and Fig. 16(c) is an exploded view of the interlayer film for laminated glass according to the sixth embodiment of the present invention. Fig. 17(a) is a plan view of an interlayer film for laminated glass according to a seventh embodiment of the present invention, Fig. 17(b) is a cross-sectional view taken along line A-A in Fig. 17(a), and Fig. 17(c) is an exploded view of the interlayer film for laminated glass according to the seventh embodiment of the present invention.

[0014] [First Embodiment of Interlayer Film for Laminated Glass] An interlayer film for laminated glass according to a first embodiment of the present invention will be described with reference to Figure 1. The interlayer film for laminated glass 1 according to the first embodiment of the present invention includes a functional film 10 and one or more first polymer sheets 20a, 20b provided on one side of the functional film 10. When viewed in a projection in the thickness direction, the functional film 10 is included in at least the region of the first polymer sheet 20a, 20b, which is in contact with the functional film 10. In this embodiment, the interlayer film for laminated glass 1 further includes one or more gap filler polymer sheets 30 provided on the side of the first polymer sheets 20a, 20b opposite the functional film side. Note that the phrase "the functional film 10 is included in the region of the first polymer sheet 20a" means that the entire functional film 10 is contained within the region of the first polymer sheet 20a when viewed in a projection in the thickness direction. Furthermore, in a projection view in the thickness direction, it is sufficient that at least a portion of the outer periphery of the functional film 10 is located inside the outer periphery of the first polymer sheet 20a, but it is preferable that the entire outer periphery of the functional film 10 is located inside the outer periphery of the first polymer sheet 20a. With the above configuration, the step-conforming ability of the first polymer sheets 20a, 20b can reduce gaps that occur at the edge 12 of the functional film 10. Furthermore, the difference in thickness between the region where the functional film 10 is present and the region where the functional film 10 is not present, which occurs due to the provision of the functional film 10, can be filled by the gap filler polymer sheet 30, thereby suppressing the occurrence of steps in the thickness direction of the interlayer film for laminated glass.

[0015] In the interlayer film 1 for laminated glass shown in FIG. 1 , the number of first polymer sheets 20a, 20b provided on one surface 11 of the functional film 10 is two, but it may be one, or three or more. The multiple first polymer sheets 20a, 20b may be stacked in the thickness direction as shown in FIG. 1 . In the interlayer film 1 for laminated glass, the first polymer sheets 20a, 20b and the gap filler polymer sheet 30 are bonded to each other, and the functional film 10 is also bonded to the first polymer sheet 20a. These polymer sheets and functional films are preferably bonded by thermocompression bonding, as described below.

[0016] The interlayer film for laminated glass 1 of the first embodiment of the present invention has a surface roughness (R ｚｊｉｓ９４ ) is preferably 1 μm or more and 100 μm or less. In the interlayer film for laminated glass 1 of the first embodiment of the present invention, the surface 2 on the side of the polymer sheet for gap filler constitutes one surface of the interlayer film for laminated glass 1, and is the surface that comes into contact with the glass plate when it is bonded to the glass plate. In the interlayer film for laminated glass 1 of the first embodiment of the present invention, the surface roughness (R ｚｊｉｓ９４ When the surface roughness (R ) of the surface 2 of the interlayer film for laminated glass 1 on the side of the gap filler polymer sheet is 1 μm or more and 100 μm or less, air can be prevented from remaining when the interlayer film for laminated glass 1 is pressure-bonded to a glass plate. ｚｊｉｓ９４ ) is more preferably 3 μm or more and 80 μm or less, even more preferably 5 μm or more and 70 μm or less, and even more preferably 25 μm or more and 50 μm or less.

[0017] In addition, the surface roughness (R ｚｊｉｓ９４ ) is the ten-point average roughness measured in accordance with JIS B 601-1994. ｚｊｉｓ９４ As a measuring instrument for measuring the surface roughness (R ｚｊｉｓ９４More specifically, the surface roughness (Rz) can be measured using a palpator needle with a tip radius of 2 μm and a tip angle of 90° under the following measurement conditions: a cutoff value during measurement of 2.5 mm, a reference length of 2.5 mm, a measurement length of 12.5 mm, a preliminary length of 2.5 mm, and a palpator needle feed rate of 0.5 mm / sec, in an environment of 23° C. and 30% RH. When the surface of the interlayer film 1 for laminated glass is embossed with ruled lines, the ten-point average roughness (Rz) is measured by moving the palpator needle in a direction perpendicular to the direction of the ruled lines. ｚｊｉｓ９４ ) can be determined by measuring 10 points at equal intervals from one end to the other end and calculating the average value. ｚｊｉｓ９４ ) may be measured across both the first polymer sheet 20b and the gap filler polymer sheet 30.

[0018] For example, by forming an uneven shape on the surface 2 of the interlayer film for laminated glass 1 that faces the polymer sheet for gap filler, the surface roughness (R ｚｊｉｓ９４ ) can be 1 μm or more and 100 μm or less. The method for forming the uneven shape is not particularly limited, and examples thereof include lip embossing, embossing roll, and calender roll. Note that the surface 2 of the interlayer film 1 for laminated glass facing the polymer sheet for gap filler may have a regular shape or a random shape.

[0019] When viewed in a projection in the thickness direction, the outer periphery of the gap filler polymer sheet 30 may be located outside, inside, or at the same position as the outer peripheries of each of the first polymer sheets 20a, 20b. That is, when viewed in a projection in the thickness direction, the outer periphery of the gap filler polymer sheet 30 may be located at the same position as, outside, or inside the outer peripheries of each of the first polymer sheets 20a, 20b. However, it is preferable that the outer periphery of the opening 31 of the gap filler polymer sheet 30 be located at the same position as or approximately the same position as the outer periphery of the functional film 10.

[0020] When viewed in a projection in the thickness direction, the size of the outer periphery of the gap filler polymer sheet 30 may be larger, smaller, or the same as the outer periphery of each of the first polymer sheets 20a, 20b. "Larger than the outer periphery" means that, when viewed in a projection, the entire outer periphery of the gap filler polymer sheet 30 is located outside the outer periphery of each of the first polymer sheets 20a, 20b. "Smaller than the outer periphery" means that, when viewed in a projection, the entire outer periphery of the gap filler polymer sheet 30 is located inside the outer periphery of each of the first polymer sheets 20a, 20b. "The same as the outer periphery" means that, when viewed in a projection in the thickness direction, the outer periphery of the gap filler polymer sheet 30 coincides with the outer periphery of each of the first polymer sheets 20a, 20b. Furthermore, when viewed in a projection in the thickness direction, the distance (W2) between the outer periphery of each of the first polymer sheets 20a, 20b and the outer periphery of the gap filler polymer sheet 30 is preferably 0 mm or more and 10 mm or less over the entire periphery. When the distance (W2) between the outer periphery of each of the first polymer sheets 20a, 20b and the outer periphery of the polymer sheet for gap filler 30 is 0 mm or more and 10 mm or less in projection view in the thickness direction, when the interlayer film for laminated glass 1 is provided between two glass plates, it is easy to make the thickness of the interlayer film for laminated glass 1 uniform. From this viewpoint, when projected view in the thickness direction, the distance (W2) between the outer periphery of each of the first polymer sheets 20a, 20b and the outer periphery of the polymer sheet for gap filler 30 over the entire periphery is preferably 0 mm or more and 5 mm or less, more preferably 0 mm or more and 3 mm or less, and even more preferably 0 mm or more and 1 mm or less. As shown in FIG. 2, it is preferable that the outer peripheries 22a, 22b of the first polymer sheets 20a, 20b and the outer periphery 32 of the gap filler polymer sheet 30A are the same size. In particular, it is particularly preferable that the outer periphery 32 of the gap filler polymer sheet 30 and the outer peripheries 22a, 22b of the first polymer sheets 20a, 20b are arranged at the same position as each other when viewed in a projection in the thickness direction.

[0021] Also preferred is an embodiment in which, in a projection view in the thickness direction, the entire periphery of the gap filler polymer sheet 30 is located inside the periphery of the first polymer sheets 20a, 20b, as shown in Fig. 1. If the periphery of the gap filler polymer sheet 30 is located inside the periphery of the first polymer sheets 20a, 20b, a step will occur in the thickness direction, as shown in Fig. 1. However, since the step is mostly filled in advance by the gap filler polymer sheet 30 and is located on the outermost surface of the interlayer film 1, it is largely filled in by the deformation of the interlayer film 1 when it is pressed against the glass. Therefore, even if there is a step, defects such as the formation of a gap between the glass plate and the interlayer film are unlikely to occur.

[0022] The polymer sheet for gap filler 30 preferably has openings 31 in an area overlapping with the functional film 10 when viewed in a projection in the thickness direction. This makes it easier to suppress the occurrence of steps in the thickness direction that would otherwise occur when the interlayer film for laminated glass 1 contains the functional film 10.

[0023] When viewed in a projection view in the thickness direction, the shape of the opening 31 of the gap filler polymer sheet 30 is preferably similar to the outer shape of the functional film 10. This makes it possible to further reduce gaps that occur at the edges 12 of the functional film 10.

[0024] In a projection view in the thickness direction, the inner periphery of the opening 31 in the gap filler polymer sheet 30 and the outer periphery of the functional film 10 are preferably located at the same position or at similar positions. Note that, in a projection view in the thickness direction, the inner periphery of the opening 31 in the gap filler polymer sheet 30 may be larger, smaller, or the same as the outer periphery of the functional film 10. Specifically, in a projection view in the thickness direction, the distance (W1) between the inner periphery of the opening 31 in the gap filler polymer sheet 30 and the outer periphery of the functional film 10 is preferably 5 mm or less over the entire circumference. When the distance (W1) between the inner periphery of the opening 31 in the gap filler polymer sheet 30 and the outer periphery of the functional film 10 is 5 mm or less in a projection view in the thickness direction, the gap generated at the edge 12 of the functional film 10 can be further reduced. From this viewpoint, when viewed in a projection view in the thickness direction, the distance (W1) between the inner periphery of the opening 31 of the polymer sheet for gap fillers 30 and the outer periphery of the functional film 10 is more preferably 3 mm or less over the entire periphery, and even more preferably 1 mm or less. The lower limit of the distance (W1) is not particularly limited, but the smaller the better, as long as it is 0 mm or more.

[0025] Furthermore, when viewed in a projection in the thickness direction, it is more preferable that the outer periphery of the functional film 10 is positioned at the same position as the inner periphery of the opening 31 or at a position more inward than the inner periphery of the opening 31, and it is even more preferable that the outer periphery of the functional film 10 is positioned either at the same position as the inner periphery of the opening 31 or at a position more inward than the inner periphery of the opening 31 over the entire circumference.

[0026] In FIG. 1, the gap filler polymer sheet 30 is made up of one polymer sheet, but it may be made up of two or more laminated polymer sheets.

[0027] The first polymer sheets 20a, 20b and the cap filler polymer sheet 30 each contain a resin. The resin used in the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 may be a curable resin such as a thermosetting resin or a moisture-curing resin, but a thermoplastic resin is preferred. The use of a thermoplastic resin makes it easier for the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 to adhere to each other by thermocompression bonding. Examples of thermoplastic resins used in the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 include (meth)acrylic resins, polyvinyl acetal resins, polyvinyl alcohol resins (PVA), polyurethane resins (PU), ethylene-vinyl acetate copolymer resins (EVA), saponified ethylene-vinyl acetate copolymers (EVOH), ethylene-methacrylic acid copolymer resins, ionomer resins, isobutylene resins, styrene-isoprene copolymer resins, and styrene-butadiene copolymer resins. Among the above, the thermoplastic resin is preferably a polyvinyl acetal resin, an ethylene-vinyl acetate copolymer resin, or a (meth)acrylic resin, more preferably a polyvinyl acetal resin or an ethylene-vinyl acetate copolymer resin, and even more preferably a polyvinyl acetal resin. Use of a polyvinyl acetal resin makes it easier to improve the impact resistance of the laminated glass and to improve the adhesive strength to the glass sheets.

[0028] At least one of the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 preferably contains at least one thermoplastic resin selected from the group consisting of polyvinyl acetal resins and ethylene-vinyl acetate copolymer resins, thereby further improving the impact resistance of the laminated glass.

[0029] It is preferable that the first polymer sheets 20a, 20b and the polymer sheet for cap filler 30 use the same type of resin. Using the same type of resin facilitates thermocompression bonding. Therefore, it is preferable that the resin used for the first polymer sheets 20a, 20b and the polymer sheet for cap filler 30 is a polyvinyl acetal resin. It is also preferable that the resin used for the first polymer sheets 20a, 20b and the polymer sheet for cap filler 30 is an ethylene-vinyl acetate copolymer resin.

[0030] (Polyvinyl Acetal Resin) Hereinafter, the polyvinyl acetal resin used in the first polymer sheets 20a and 20b and the cap filler polymer sheet 30 will be described in detail.

[0031] The polyvinyl acetal resin is not particularly limited as long as it is a polyvinyl acetal resin obtained by acetalizing polyvinyl alcohol with an aldehyde. The average degree of polymerization of the PVA is preferably 200 or more, more preferably 500 or more, even more preferably 1000 or more, and even more preferably 1500 or more. When the average degree of polymerization is equal to or greater than the lower limit, the penetration resistance of the laminated glass is increased. Furthermore, the average degree of polymerization of the PVA is preferably 5000 or less, more preferably 4000 or less, and even more preferably 3500 or less. When the average degree of polymerization is equal to or less than the upper limit, the formation of an interlayer film for laminated glass is facilitated. The average degree of polymerization of polyvinyl alcohol is determined by a method in accordance with JIS K 6726 "Testing Methods for Polyvinyl Alcohol."

[0032] The aldehyde is not particularly limited, but generally, an aldehyde having 1 to 10 carbon atoms is suitably used. The aldehyde having 1 to 10 carbon atoms is not particularly limited, and examples thereof include n-butylaldehyde, isobutyraldehyde, n-valeraldehyde, 2-ethylbutyraldehyde, n-hexylaldehyde, n-octylaldehyde, n-nonylaldehyde, n-decylaldehyde, formaldehyde, acetaldehyde, and benzaldehyde. These aldehydes may be used alone or in combination of two or more. The number of carbon atoms in the acetal group contained in the polyvinyl acetal resin is not particularly limited, but is preferably 1 to 10, more preferably 3 to 5, even more preferably 4 or 5, and particularly preferably 4. As specific aldehydes, among those mentioned above, n-butylaldehyde, n-hexylaldehyde, and n-valeraldehyde are preferred, and n-butylaldehyde is more preferred. Therefore, the polyvinyl acetal resin is preferably a polyvinyl butyral resin, and both the polyvinyl acetal resins (1) and (2) are preferably polyvinyl butyral resins.

[0033] Polyvinyl acetal resins generally have acetal groups, hydroxyl groups, and acetyl groups in their side chains. The hydroxyl group content (hydroxyl group amount) of the polyvinyl acetal resin is, for example, 17 mol% to 38 mol%, preferably 20 mol% to 36 mol%. The acetalization degree of the polyvinyl acetal resin is, for example, 42 mol% to 85 mol%, preferably 55 mol% to 80 mol%. The acetylation degree of the polyvinyl acetal resin (acetyl group amount) is, for example, 0.01 mol% to 30 mol%, preferably 0.1 mol% to 25 mol%.

[0034] The hydroxyl group content of the polyvinyl acetal resin is the molar fraction calculated by dividing the amount of ethylene groups having hydroxyl groups by the total amount of ethylene groups in the main chain, and is expressed as a percentage. The amount of ethylene groups having hydroxyl groups can be measured, for example, in accordance with JIS K 6728 "Testing Methods for Polyvinyl Butyral."

[0035] The degree of acetalization is a molar fraction calculated by subtracting the amount of ethylene groups having hydroxyl groups bonded thereto and the amount of ethylene groups having acetyl groups bonded thereto from the total amount of ethylene groups in the main chain, and dividing the result by the total amount of ethylene groups in the main chain, expressed as a percentage. The degree of acetalization (degree of butyralization) may be calculated from the results of measurements performed in accordance with JIS K 6728 "Test Methods for Polyvinyl Butyral." The degree of acetylation is a molar fraction calculated by dividing the amount of ethylene groups having acetyl groups bonded thereto by the total amount of ethylene groups in the main chain, expressed as a percentage. The amount of ethylene groups having acetyl groups bonded thereto can be measured, for example, in accordance with JIS K 6728 "Test Methods for Polyvinyl Butyral."

[0036] The polyvinyl acetal resin is typically an unmodified polyvinyl acetal resin, but may also be a modified polyvinyl acetal resin. The modified polyvinyl acetal resin has a structure (modifying group) other than an acetal group, a hydroxyl group, and an acetyl group, and preferably has the modifying group in a side chain. Examples of the modifying group include those having a polyalkylene oxide structure in the side chain, and those having an acetal group, an alkyl group other than an acetyl group (e.g., having about 2 to 30 carbon atoms) in the side chain.

[0037] (Ethylene-vinyl acetate copolymer resin) The ethylene-vinyl acetate copolymer resin used in the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 may be a non-crosslinked ethylene-vinyl acetate copolymer resin or a high-temperature crosslinked ethylene-vinyl acetate copolymer resin. In addition, modified ethylene-vinyl acetate resins such as saponified ethylene-vinyl acetate copolymer and hydrolyzed ethylene-vinyl acetate may also be used as the ethylene-vinyl acetate copolymer resin.

[0038] The ethylene-vinyl acetate copolymer resin preferably has a vinyl acetate content of 10% by mass or more and 50% by mass or less, as measured in accordance with JIS K 6730 "Testing Methods for Ethylene-Vinyl Acetate Resins." By ensuring that the vinyl acetate content is at or above these lower limits, adhesion to glass plates and the like is improved, and the penetration resistance of the laminated glass is likely to be improved. Furthermore, by ensuring that the vinyl acetate content is at or below these upper limits, the breaking strength of the interlayer film for laminated glass is increased, and the impact resistance of the laminated glass is improved.

[0039] (Plasticizer) When the resin used is a thermoplastic resin, the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 may further contain a plasticizer. By including a plasticizer in the first polymer sheets 20a, 20b and the cap filler polymer sheet 30, the interlayer film 1 for laminated glass becomes flexible, and as a result, the laminated glass also becomes flexible. Furthermore, when the glass plate is inorganic glass, it is possible to improve adhesion to the glass plate. When a polyvinyl acetal resin is used as the thermoplastic resin, it is particularly effective to include a plasticizer in the resin layer containing the thermoplastic resin.

[0040] The plasticizers used in the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 are described in detail below. Examples of plasticizers used in the first polymer sheets 20a, 20b and the cap filler polymer sheet 30 include organic ester plasticizers such as monobasic organic acid esters and polybasic organic acid esters, and phosphorus-based plasticizers such as organic phosphate-based plasticizers and organic phosphite-based plasticizers. Among these, organic ester plasticizers are preferred. The plasticizer is preferably a liquid plasticizer. A liquid plasticizer is a plasticizer that is liquid at room temperature (23°C) and atmospheric pressure (1 atmosphere).

[0041] Examples of monobasic organic acid esters include esters of glycols and monobasic organic acids. Examples of glycols include polyalkylene glycols in which each alkylene unit has 2 to 4 carbon atoms, preferably 2 or 3 carbon atoms, and the number of repeating alkylene units is 2 to 10, preferably 2 to 4. Examples of glycols include monoalkylene glycols in which each alkylene unit has 2 to 4 carbon atoms, preferably 2 or 3 carbon atoms, and the number of repeating units is 1. Specific examples of glycols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, and butylene glycol. Examples of monobasic organic acids include organic acids having 3 to 10 carbon atoms, such as butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, 2-ethylpentanoic acid, heptyl acid, n-octylic acid, 2-ethylhexyl acid, n-nonylic acid, and decylic acid.

[0042] Preferred monobasic organic acid esters include compounds represented by the following formula (1): In the above formula (1), R1 and R2 each represent an organic group having 2 to 10 carbon atoms, R3 represents an ethylene group, an isopropylene group, or an n-propylene group, and p represents an integer of 3 to 10. In the above formula (1), R1 and R2 each preferably have 5 to 10 carbon atoms, more preferably 6 to 10 carbon atoms. The organic groups of R1 and R2 are preferably hydrocarbon groups, more preferably alkyl groups.

[0043] Specific glycol esters include ethylene glycol di-2-ethyl butyrate, 1,2-propylene glycol di-2-ethyl butyrate, 1,3-propylene glycol di-2-ethyl butyrate, 1,4-butylene glycol di-2-ethyl butyrate, 1,2-butylene glycol di-2-ethyl butyrate, diethylene glycol di-2-ethyl butyrate, diethylene glycol dicaprylate, diethylene glycol di-2-ethylhexanoate, dipropylene glycol di-2-ethyl butyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethylene glycol di-2-ethylpentanoate, triethylene glycol di-n-heptanoate, triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylpropanoate, tetraethylene glycol di-n-heptanoate, tetraethylene glycol di-2-ethylhexanoate, tetraethylene glycol di-2-ethylbutyrate, and the like.

[0044] Examples of polybasic organic acid esters include ester compounds of dibasic organic acids having 4 to 12 carbon atoms, such as adipic acid, sebacic acid, and azelaic acid, with alcohols having 4 to 10 carbon atoms. The alcohols having 4 to 10 carbon atoms may be linear, branched, or cyclic. Specific examples include dibutyl sebacate, dioctyl azelaate, dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, diisononyl adipate, heptylnonyl adipate, di-(2-butoxyethyl) adipate, dibutyl carbitol adipate, and mixed adipates. Oil-modified alkyd sebacates are also suitable. Examples of mixed adipates include adipates prepared from two or more alcohols selected from alkyl alcohols having 4 to 9 carbon atoms and cyclic alcohols having 4 to 9 carbon atoms. Examples of the organic phosphoric acid plasticizer include phosphoric acid esters such as tributoxyethyl phosphate, isodecylphenyl phosphate, and triisopropyl phosphate. The plasticizers may be used alone or in combination of two or more.

[0045] Among the above-mentioned plasticizers, the plasticizer is preferably selected from di-(2-butoxyethyl) adipate (DBEA), triethylene glycol di-2-ethylhexanoate (3GO), triethylene glycol di-2-ethylbutyrate (3GH), and triethylene glycol di-2-ethylpropanoate, more preferably from triethylene glycol di-2-ethylhexanoate (3GO), triethylene glycol di-2-ethylbutyrate (3GH), and triethylene glycol di-2-ethylpropanoate, still more preferably from triethylene glycol di-2-ethylhexanoate and triethylene glycol di-2-ethylbutyrate, with triethylene glycol di-2-ethylhexanoate being particularly preferred.

[0046] In the first polymer sheets 20a, 20b and the polymer sheet for cap filler 30, the content of the plasticizer is not particularly limited, but is, for example, 10 parts by mass or more and 100 parts by mass or less, preferably 15 parts by mass or more and 90 parts by mass or less, per 100 parts by mass of the thermoplastic resin.

[0047] The thickness of each of the first polymer sheets 20a and 20b is not particularly limited, but is, for example, 50 μm to 1500 μm, preferably 100 μm to 1000 μm, and more preferably 150 μm to 900 μm.

[0048] When there are multiple first polymer sheets 20a, 20b, the total thickness of the first polymer sheets 20a, 20b is not particularly limited, but is, for example, 100 μm or more and 3000 μm or less, preferably 200 μm or more and 2000 μm or less, and more preferably 300 μm or more and 1800 μm or less.

[0049] The thickness of the gap filler polymer sheet 30 is preferably approximately the same as the thickness of the functional film 10. From this viewpoint, the ratio of the thickness of the gap filler polymer sheet 30 to the thickness of the functional film 10 (thickness of the gap filler polymer sheet / thickness of the functional film) is preferably 0.5 or more and 1.5 or less, more preferably 0.8 or more and 1.2 or less.

[0050] At least one of the first polymer sheets 20a, 20b may contain a colorant. Examples of colorants include pigments, dyes, and the like. Examples of pigments include, but are not limited to, metal oxide pigments such as titanium oxide and iron oxide; inorganic pigments such as carbon black, clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white; and organic pigments such as azo pigments, quinacridone pigments, diketopyrrolopyrrole pigments, perylene pigments, perinone pigments, benzimidazolone pigments, vat pigments, isoindoline pigments, isoindolinone pigments, metal chelate azo pigments, phthalocyanine pigments, indanthrone pigments, dioxane pigments, and indigo pigments. Known dyes can be used, including azo dyes, anthraquinone dyes, indigoid dyes, and stilbene dyes.

[0051] At least one of the first polymer sheets 20a, 20b may contain a heat-shielding agent. Since the heat-shielding agent also blocks a certain amount of visible light, the first polymer sheets 20a, 20b can also be colored by containing the heat-shielding agent. The heat-shielding agent is typically a material that can absorb infrared rays with a wavelength of 780 nm or more, i.e., heat rays. The heat-shielding agent is made of an inorganic material, and typically heat-shielding particles are used. Specific examples thereof include metal oxide particles, lanthanum hexaboride (LaB ６) particles and other particles. Examples of metal oxide particles include tin oxide particles such as aluminum-doped tin oxide particles, indium-doped tin oxide particles, and antimony-doped tin oxide particles (ATO particles); zinc oxide particles such as gallium-doped zinc oxide particles (GZO particles), indium-doped zinc oxide particles (IZO particles), aluminum-doped zinc oxide particles (AZO particles), tin-doped zinc oxide particles, and silicon-doped zinc oxide particles; titanium oxide particles such as niobium-doped titanium oxide particles; indium oxide particles such as tin-doped indium oxide particles (ITO particles); and tungsten oxide particles such as sodium-doped tungsten oxide particles, cesium-doped tungsten oxide particles (CWO particles), thallium-doped tungsten oxide particles, and rubidium-doped tungsten oxide particles. Heat-shielding particles other than these may also be used. The heat-shielding agent may be used alone or in combination of two or more.

[0052] Furthermore, when a plurality of first polymer sheets are provided (for example, when first polymer sheets 20a and 20b are provided), the first polymer sheets may have different compositions to perform different functions, for example, the first polymer sheet 20a may contain a heat-shielding agent and the first polymer sheet 20b may contain a colorant. Alternatively, for example, the first polymer sheet 20a may contain at least one of a heat-shielding agent and a colorant, and the first polymer sheet 20b may contain neither a heat-shielding agent nor a colorant.

[0053] The functional film may be a light control film, a display element film, or an optical film. Examples of the optical film include a film having a function of absorbing specific light or a function of reflecting specific light, and specific examples thereof include a polarizing film, a retardation film, and an antireflection film.

[0054] Examples of functional films include P-polarized light reflective films, hologram films, heat ray reflective films, light control films, display element films, transparent conductive films, touch sensor films, circuit films, solar light films, and electrically controllable films. Of the above, heat ray reflective films and light control films are preferred as functional films.

[0055] The functional film is not particularly limited in terms of material, but may contain at least a general-purpose resin such as a polyester resin, such as polyethylene terephthalate resin (PET) or polyethylene naphthalate resin (PEN), a (meth)acrylic resin, TAC, PES resin, or polyimide resin, with polyethylene terephthalate resin being preferred. The outermost surface of the functional film preferably contains a thermoplastic resin. For example, if the outermost surface of the functional film 10 that contacts the first polymer sheet 20a contains a thermoplastic resin, the functional film 10 can be easily bonded to the first polymer sheet 20a by thermocompression bonding. Similarly, as described below, if the outermost surface of the functional film 10 that contacts the second polymer sheet 40 contains a thermoplastic resin, the functional film 10 can be easily bonded to the second polymer sheet 40 by thermocompression bonding. The functional film 10 preferably contains a PET film, and the PET film is preferably disposed in a position that contacts the first polymer sheet 20a.

[0056] The heat-reflective film is a film-like member having an infrared-reflective layer. Specifically, the heat-reflective film is preferably a heat-reflective film comprising two resin films and an infrared-reflective layer disposed between the two resin films. Examples of the infrared-reflective layer include a resin film with a metal foil, a multilayer laminate film in which a metal layer and a dielectric layer are formed on a resin layer, a multilayer resin film, and a liquid crystal film. Resin films used in the infrared-reflective film are not particularly limited, but include films containing polyethylene terephthalate resin (e.g., PET film), polyester resin films such as PEN film, (meth)acrylic resin films, TAC film, PES resin film, and polyimide resin films. Among these, polyester resin films are preferred from the viewpoint of ease of handling, and PET film is more preferred. The heat-reflective film may be composed of only the infrared-reflective layer, omitting the resin film.

[0057] The light control film is a film-like component having a light control element. Specifically, the light control element is preferably a light control film comprising two resin films and a light control layer disposed between the two resin films. Resin films used in the light control element are not particularly limited, but include films containing polyethylene terephthalate resin (e.g., PET film), polyester resin films such as PEN film, (meth)acrylic resin films, TAC film, PES resin film, and polyimide resin films. Among these, polyester resin films are preferred from the viewpoint of ease of handling, and PET film is more preferred. Furthermore, each of the two resin films has a conductive layer forming an electrode on the surface facing the light control layer.

[0058] The light-controlling layer changes its visible light transmittance by switching between application and non-application of a voltage between the conductive layers of two resin films. The light-controlling layer may be composed of a liquid crystal layer such as a polymer-dispersed liquid crystal (PDLC), and the light-controlling film may be a PDLC film. The light-controlling film may also be a suspended particle device (SPD) film, an electrochromic film, an electrophoretic film device, a guest-host liquid crystal (GHLC) film, a polymer network liquid crystal (PNLC) film, or the like. Therefore, the light-controlling layer may be an SPD layer containing a resin matrix and a light-controlling suspension dispersed in the resin matrix, or an electrochromic material layer. Alternatively, the light-controlling layer may be an electrophoretic layer containing electrophoretic particles and a dispersant for dispersing the electrophoretic particles.

[0059] The thickness of the functional film is not particularly limited, but is, for example, 30 μm to 1200 μm, preferably 50 μm to 1000 μm, more preferably 75 μm to 750 μm, and even more preferably 100 μm to 500 μm.

[0060] The surface 2 of the interlayer film for laminated glass 1 according to the first embodiment of the present invention facing the polymer sheet for gap fillers may be protected by a protective release film. A resin film may be used as the protective release film, and a resin film having a release-treated surface that has been subjected to a release treatment using a silicone release agent or the like is preferred.

[0061] [Second embodiment of interlayer film for laminated glass] An interlayer film for laminated glass according to a second embodiment of the present invention will be described with reference to Fig. 3. The following mainly describes the differences from the interlayer film for laminated glass according to the first embodiment of the present invention, and omits a description of the similarities between the interlayer film for laminated glass according to the first embodiment of the present invention.

[0062] The interlayer film for laminated glass 1B of the second embodiment of the present invention differs from the interlayer film for laminated glass of the first embodiment in that it further comprises a second polymer sheet 40. That is, the interlayer film for laminated glass 1B of the second embodiment of the present invention further comprises, in addition to the functional film 10, polymer sheets 20a and 20b, and gap filler polymer sheet 30, a second polymer sheet 40 provided on the other side of the functional film 10. In this embodiment, the provision of the second polymer sheet 40 allows both surfaces 2 and 3 of the interlayer film for glass 1B to be easily adhered to a glass plate without the need for an additional resin layer or the like. Note that, although the interlayer film for laminated glass 1B of the second embodiment of the present invention includes one second polymer sheet 40, two or more second polymer sheets 40 may be used. Preferably, two or more second polymer sheets 40 are stacked in the thickness direction.

[0063] When viewed in a projection in the thickness direction, the functional film 10 may be included in the region of at least the second polymer sheet 40, of the one or more second polymer sheets, that is in contact with the functional film 10. In other words, when viewed in a projection in the thickness direction, the entire functional film 10 is contained within the region of the second polymer sheet 40. Furthermore, when viewed in a projection in the thickness direction, it is sufficient that at least a part of the periphery of the functional film 10 is located inside the periphery of the second polymer sheet 40, but it is preferable that the entire periphery of the functional film 10 is located inside the periphery of the second polymer sheet 40.

[0064] The surface roughness (R ｚｊｉｓ９４ ) is preferably 1 μm or more and 100 μm or less. The surface 3 on the second polymer sheet side of the interlayer film for laminated glass 1B of the second embodiment of the present invention is the surface that constitutes the other surface of the interlayer film for laminated glass 1, and is the surface that comes into contact with the glass plate when it is bonded to the glass plate. The surface roughness (R ｚｊｉｓ９４ When the surface roughness (R ) of the surface 3 on the side of the second polymer sheet in the interlayer film for laminated glass 1B of the second embodiment of the present invention is 1 μm or more and 100 μm or less, the generation of residual air can be further suppressed when the interlayer film for laminated glass 1B of the second embodiment of the present invention is pressure-bonded to a glass plate. ｚｊｉｓ９４ ) is more preferably 3 μm or more and 80 μm or less, even more preferably 5 μm or more and 70 μm or less, and even more preferably 25 μm or more and 50 μm or less.

[0065] As with the interlayer film 1 for laminated glass of the first embodiment of the present invention, for example, by forming an uneven shape on the surface 3 on the side of the second polymer sheet in the interlayer film 1B for laminated glass of the second embodiment of the present invention, the surface roughness (R ｚｊｉｓ９４) can be 1 μm or more and 100 μm or less. The method for forming the uneven shape is not particularly limited, and examples thereof include lip embossing, embossing roll, and calender roll. Note that the unevenness on the surface 3 facing the second polymer sheet in the interlayer film for laminated glass 1B of the second embodiment of the present invention may have a regular shape or a random shape.

[0066] When viewed as a projection in the thickness direction, the size of the outer periphery of the polymer sheet 30 for gap filler may be larger, smaller, or the same as the outer periphery of the second polymer sheet 40. "Larger than the outer periphery" means that when viewed as a projection, the entire periphery of the polymer sheet 30 for gap filler is located outside the periphery of the second polymer sheet 40; "smaller than the outer periphery" means that when viewed as a projection, the entire periphery of the polymer sheet 30 for gap filler is located inside the periphery of the second polymer sheet 40; and "the same as the outer periphery" means that when viewed as a projection, the periphery of the polymer sheet 30 for gap filler coincides with the periphery of the second polymer sheet 40. When viewed as a projection in the thickness direction, the distance (W2) between the periphery of the second polymer sheet 40 and the periphery of the polymer sheet 30 for gap filler is preferably 0 mm or more and 10 mm or less over the entire periphery. When viewed as a projection in the thickness direction, if the distance (W2) between the outer periphery of the second polymer sheet 40 and the outer periphery of the polymer sheet for gap filler 30 is 0 mm or more and 10 mm or less, when the interlayer film for laminated glass 1A is provided between two glass plates, the thickness of the interlayer film for laminated glass 1A can be easily made constant. From this perspective, when viewed as a projection in the thickness direction, the distance (W2) between the outer periphery of the second polymer sheet 40 and the outer periphery of the polymer sheet for gap filler 30 over the entire periphery is more preferably 0 mm or more and 5 mm or less, even more preferably 0 mm or more and 3 mm or less, and still more preferably 0 mm or more and 1 mm or less.

[0067] When viewed in a projection in the thickness direction, the size of the outer periphery of the second polymer sheet 40 may be larger, smaller, or the same as the outer periphery of the first polymer sheets 20a, 20b. "Larger than the outer periphery" means that, when viewed in a projection, the entire outer periphery of the second polymer sheet 40 is located outside the outer peripheries of the first polymer sheets 20a, 20b. "Smaller than the outer periphery" means that, when viewed in a projection, the entire outer periphery of the second polymer sheet 40 is located inside the outer peripheries of the first polymer sheets 20a, 20b. "The same as the outer periphery" means that, when viewed in a projection in the thickness direction, the distance between the outer periphery of the first polymer sheets 20a, 20b and the outer periphery of the second polymer sheet 40 is preferably 0 mm or more and 10 mm or less over the entire periphery. When viewed as a projection in the thickness direction, if the distance between the outer periphery of the first polymer sheets 20a, 20b and the outer periphery of the second polymer sheet 40 is 0 mm or more and 10 mm or less, when the interlayer film for laminated glass 1B is provided between two glass plates, the thickness of the interlayer film for laminated glass 1B is more likely to be constant. From this perspective, when viewed as a projection in the thickness direction, the distance between the outer periphery of the first polymer sheets 20a, 20b and the outer periphery of the second polymer sheet 40 over the entire periphery is more preferably 0 mm or more and 5 mm or less, even more preferably 0 mm or more and 3 mm or less, and still more preferably 0 mm or more and 1 mm or less. As shown in FIG. 4 , it is preferable that the size of the outer peripheries 22a, 22b of each of the first polymer sheets 20a, 20b, the size of the outer periphery 42 of the second polymer sheet 40, and the size of the outer periphery 32 of the polymer sheet for gap filler 30C are all the same, and it is particularly preferable that the outer peripheries 22a, 22b of the first polymer sheets 20a, 20b, the size of the outer periphery 42 of the second polymer sheet 40, and the size of the outer periphery 32 of the polymer sheet for gap filler 30C are all positioned at the same positions when viewed in a projection in the thickness direction.

[0068] Like the first polymer sheets 20a, 20b and the cap filler polymer sheet 30, the second polymer sheet 40 also contains a resin. The resin used in the second polymer sheet 40 may be a curable resin such as a thermosetting resin or a moisture-curing resin, but a thermoplastic resin is preferred. The use of a thermoplastic resin makes it easier for the first polymer sheet 20a, the second polymer sheet 40, and the cap filler polymer sheet 30 to adhere to one another by thermocompression bonding. Examples of thermoplastic resins used in the second polymer sheet 40 include (meth)acrylic resins, polyvinyl acetal resins, polyvinyl alcohol resins (PVA), polyurethane resins (PU), ethylene-vinyl acetate copolymer resins (EVA), saponified ethylene-vinyl acetate copolymers (EVOH), ethylene-methacrylic acid copolymer resins, ionomer resins, isobutylene resins, styrene-isoprene copolymer resins, and styrene-butadiene copolymer resins. Among the above, the thermoplastic resin is preferably a polyvinyl acetal resin, an ethylene-vinyl acetate copolymer resin, or a (meth)acrylic resin, more preferably a polyvinyl acetal resin or an ethylene-vinyl acetate copolymer resin, and even more preferably a polyvinyl acetal resin. Use of a polyvinyl acetal resin makes it easier to improve the impact resistance of the laminated glass and to improve the adhesive strength to the glass sheets.

[0069] The second polymer sheet 40 preferably contains at least one thermoplastic resin selected from the group consisting of polyvinyl acetal resins and ethylene-vinyl acetate copolymer resins, which can further improve the impact resistance of the laminated glass.

[0070] It is preferable that the first polymer sheets 20a, 20b, the second polymer sheet 40, and the cap filler polymer sheet 30 use the same type of resin. Using the same type of resin facilitates thermocompression bonding. Therefore, it is preferable that the resins used for the first polymer sheets 20a, 20b, the second polymer sheet 40, and the cap filler polymer sheet 30 are all polyvinyl acetal resins, and it is also preferable that they are all ethylene-vinyl acetate copolymer resins.

[0071] The thickness of the second polymer sheet 40 is not particularly limited, but is, for example, 50 μm to 1500 μm, preferably 100 μm to 1000 μm, and more preferably 150 μm to 900 μm.

[0072] When there are multiple second polymer sheets, the total thickness of the second polymer sheets is not particularly limited, but is, for example, 150 μm or more and 3000 μm or less, preferably 200 μm or more and 2000 μm or less, and more preferably 300 μm or more and 1800 μm or less.

[0073] The surface 3 of the interlayer film for laminated glass 1B according to the second embodiment of the present invention facing the second polymer sheet may be protected by a protective release film. A resin film may be used as the protective release film, and a resin film having a release-treated surface that has been subjected to a release treatment using a silicone release agent or the like is preferred.

[0074] [Interlayer Film for Laminated Glass of Third Embodiment] As shown in FIG. 5 , in an interlayer film for glass 1D of a third embodiment of the present invention, a gap filler polymer sheet 30D having an opening 31 is composed of multiple polymer sheets 30a-30d arranged in a planar direction. Other aspects are the same as those of the interlayer film for laminated glass of the first embodiment of the present invention. This reduces the amount of polymer sheet waste when cutting the polymer sheet 30D into the gap filler polymer sheet. While the gap filler polymer sheet 30D is composed of four polymer sheets, it may also be composed of two, three, or five or more polymer sheets. Furthermore, even when the gap filler polymer sheet 30E is composed of multiple polymer sheets arranged in a planar direction as shown in FIG. 6 , the positional relationship between the outer peripheries 22a, 22b of the first polymer sheets 20a, 20b and the outer periphery of the gap filler polymer sheet 30E remains the same as that described in the first embodiment. The same applies to the positional relationship between the inner periphery of the gap filler polymer sheet 30E and the outer periphery of the functional film.

[0075] [Fourth Embodiment of Interlayer Film for Laminated Glass] As shown in FIG. 7 , in a fourth embodiment of the present invention, an interlayer film for glass 1F has a gap filler polymer sheet 30F having an opening 31, which is composed of multiple polymer sheets 30a-30d arranged in a planar direction. Other aspects are the same as those of the interlayer film for laminated glass of the second embodiment of the present invention. This reduces the amount of polymer sheet waste when cutting the polymer sheet 30F from the polymer sheet. While the gap filler polymer sheet 30F is composed of four polymer sheets, it may also be composed of two, three, or five or more polymer sheets. Furthermore, as shown in FIG. 8 , even when the gap filler polymer sheet 30G is composed of multiple polymer sheets arranged in a planar direction, it is particularly preferable that, when projected in the thickness direction, the positions of the outer peripheries 22a, 22b of the first polymer sheets 20a, 20b, the position of the outer periphery of the second polymer sheet 40, and the position of the outer periphery 32 of the gap filler polymer sheet 30G are the same.

[0076] [Fifth embodiment of interlayer film for laminated glass] As shown in Figure 9, the fifth embodiment of the interlayer film for laminated glass 1H of the present invention further includes a third polymer sheet 50 provided on the surface 33 opposite the first polymer sheet side of the polymer sheet for gap filler 30. This makes it even easier to prevent the occurrence of steps in the thickness direction of the interlayer film for laminated glass due to the step-conforming ability of the third polymer sheet 50.

[0077] When viewed in a projection in the thickness direction, the position of the outer periphery of the third polymer sheet 50 may be outside, inside, or the same as the position of the outer periphery of the polymer sheet for gap filler 30. When viewed in a projection in the thickness direction, the distance between the outer periphery of the third polymer sheet 50 and the outer periphery of the polymer sheet for gap filler 30 is preferably 0 mm or more and 5 mm or less over the entire periphery. When viewed in a projection in the thickness direction, if the distance between the outer periphery of the third polymer sheet 50 and the outer periphery of the polymer sheet for gap filler 30 is 0 mm or more and 5 mm or less, it becomes easier to maintain a constant thickness of the interlayer film for laminated glass 1J when the interlayer film for laminated glass 1J is provided between two glass plates. From this perspective, when viewed in a projection in the thickness direction, the distance between the outer periphery of the third polymer sheet 50 and the outer periphery of the polymer sheet for gap filler 30 over the entire periphery is more preferably 0 mm or more and 3 mm or less, and even more preferably 0 mm or more and 1 mm or less.

[0078] The positions of the outer peripheries of the first polymer sheets 20a, 20b may be outside, inside, or the same as the position of the outer periphery of the third polymer sheet 50. When viewed as a projection in the thickness direction, the distance between the outer peripheries of the first polymer sheets 20a, 20b and the outer periphery of the third polymer sheet 50 is preferably 0 mm or more and 5 mm or less over the entire periphery. When viewed as a projection in the thickness direction, if the distance between the outer periphery of the first polymer sheet 20a and the outer periphery of the third polymer sheet 50 is 0 mm or more and 5 mm or less, when the interlayer film for laminated glass 1H is provided between two glass plates, the thickness of the interlayer film for laminated glass 1H is easily made constant. From this perspective, when viewed as a projection in the thickness direction, the distance between the outer periphery of the first polymer sheets 20a, 20b and the outer periphery of the third polymer sheet 50 over the entire periphery is more preferably 0 mm or more and 3 mm or less, and even more preferably 0 mm or more and 1 mm or less.

[0079] As shown in Figure 10, when viewed in a projection in the thickness direction, it is particularly preferable that the positions of the outer peripheries 22a, 22b of the first polymer sheets 20a, 20b, the position of the outer periphery 52 of the third polymer sheet 50, and the position of the outer periphery 32 of the gap filler polymer sheet 30I are the same.

[0080] Like the first polymer sheets 20a, 20b and the cap filler polymer sheet 30, the third polymer sheet 50 also contains a resin. The resin used in the second polymer sheet 40 may be a curable resin such as a thermosetting resin or a moisture-curable resin, but a thermoplastic resin is preferred. The use of a thermoplastic resin facilitates adhesion between the first polymer sheet 20b, the cap filler polymer sheet 30, and the third polymer sheet 50 by thermocompression bonding. Examples of thermoplastic resins used in the third polymer sheet 50 include (meth)acrylic resins, polyvinyl acetal resins, polyvinyl alcohol resins (PVA), polyurethane resins (PU), ethylene-vinyl acetate copolymer resins (EVA), saponified ethylene-vinyl acetate copolymers (EVOH), ethylene-methacrylic acid copolymer resins, ionomer resins, isobutylene resins, styrene-isoprene copolymer resins, and styrene-butadiene copolymer resins. Among the above, the thermoplastic resin is preferably a polyvinyl acetal resin, an ethylene-vinyl acetate copolymer resin, or a (meth)acrylic resin, more preferably a polyvinyl acetal resin or an ethylene-vinyl acetate copolymer resin, and even more preferably a polyvinyl acetal resin. Use of a polyvinyl acetal resin makes it easier to improve the impact resistance of the laminated glass and to improve the adhesive strength to the glass sheets.

[0081] The third polymer sheet 50 preferably contains at least one thermoplastic resin selected from the group consisting of polyvinyl acetal resins and ethylene-vinyl acetate copolymer resins, which further improves the impact resistance of the laminated glass.

[0082] It is preferable that the first polymer sheet 20b, the polymer sheet for cap filler 30, and the third polymer sheet 50 are made of the same type of resin. Using the same type of resin facilitates thermocompression bonding. Therefore, it is preferable that the resins used for the first polymer sheet 20b, the polymer sheet for cap filler 30, and the third polymer sheet 50 are all polyvinyl acetal resins, and it is also preferable that they are all ethylene-vinyl acetate copolymer resins.

[0083] The thickness of the third polymer sheet 50 is not particularly limited, but is, for example, 50 μm to 1500 μm, preferably 100 μm to 1000 μm, and more preferably 150 μm to 900 μm.

[0084] When multiple third polymer sheets are present, the total thickness of the third polymer sheets is not particularly limited, but is, for example, 100 μm or more and 3000 μm or less, preferably 200 μm or more and 2000 μm or less, and more preferably 300 μm or more and 1800 μm or less.

[0085] The interlayer film for laminated glass of the fifth embodiment of the present invention may also further include a second polymer sheet 40 provided on the other surface side of the functional film 10, similar to the interlayer film for laminated glass 1B of the second embodiment of the present invention.

[0086] [Sixth Embodiment of Interlayer Film for Laminated Glass] As shown in FIG. 16 , in an interlayer film for laminated glass 1J according to a sixth embodiment of the present invention, a portion of the gap filler polymer sheet 30J is cut out (see reference numeral 34). This facilitates passing wiring of a functional film through the gap filler polymer sheet 30J. In this case, the periphery of the gap filler polymer sheet 30J refers to the periphery excluding the cut-out portion 34 of the gap filler polymer sheet 30J. In this case, "over the entire periphery" means the entire periphery excluding the cut-out portion 34 of the gap filler polymer sheet 30J. In the interlayer film for laminated glass 1J according to the sixth embodiment of the present invention, the gap filler polymer sheet 30J has one cut-out portion, but may have two or more cut-out portions. The proportion of the cut-out portion is not particularly limited, but is, for example, 20% or less, preferably 0.1% to 10% and more preferably 0.2% to 5% of the periphery of the gap filler polymer sheet. In the interlayer films for laminated glass according to the first to fifth embodiments of the present invention, a portion of the polymer sheet for gap filler may also be cut out.

[0087] [Seventh Embodiment of Interlayer Film for Laminated Glass] As shown in FIG. 17 , an interlayer film 1K for laminated glass according to a seventh embodiment of the present invention includes a functional film 10a in addition to the functional film 10. While the interlayer film 1K for laminated glass according to the seventh embodiment of the present invention includes two functional films 10, 10a, the interlayer film for laminated glass according to the seventh embodiment of the present invention may include three or more functional films. This increases the functionality of the interlayer film for laminated glass. Furthermore, when the interlayer film for laminated glass includes multiple functional films, a polymer sheet 20a may be interposed between the two functional films 10, 10a, as in the interlayer film for laminated glass 1K shown in FIG. 17 . This prevents peeling between the two functional films 10, 10a.

[0088] The interlayer films for laminated glass of the first to seventh embodiments can be combined with one another.

[0089] The interlayer films for laminated glass of the first to seventh embodiments are merely examples of the interlayer film for laminated glass of the present invention, and therefore the interlayer films for laminated glass of the first to seventh embodiments do not limit the interlayer film for laminated glass of the present invention.

[0090] [Method for manufacturing an interlayer film for laminated glass] The method for manufacturing an interlayer film for laminated glass of the present invention includes a step of laminating a functional film, a first polymer sheet, and a polymer sheet for gap filler so that the functional film, the first polymer sheet, and the polymer sheet for gap filler are arranged in this order. In this step, it is not necessary to laminate the functional film, the first polymer sheet, and the polymer sheet for gap filler all at once. For example, one or more polymer sheets may be laminated on one side of the functional film, and then the polymer sheet for gap filler may be laminated on the side opposite the functional film side of the polymer sheet laminated on the functional film. The functional film and polymer sheet used in the method for manufacturing an interlayer film for laminated glass of the present invention have already been explained in the section on interlayer films for laminated glass, so explanation of the functional film and polymer sheet will be omitted. Conventionally known methods can be used for the method of laminating one or more polymer sheets on one side of the functional film and the method of laminating the polymer sheet for gap filler on the side opposite the functional film side of the polymer sheet laminated on the functional film.

[0091] The interlayer film for laminated glass of the second embodiment of the present invention can be produced, for example, by a production method including a step of laminating a second polymer sheet, a functional film, a first polymer sheet, and a polymer sheet for a gap filler so that they are arranged in this order: the second polymer sheet, the functional film, the first polymer sheet, and the polymer sheet for a gap filler. The interlayer film for laminated glass of the fifth embodiment of the present invention can be produced, for example, by a production method including a step of laminating a functional film, a first polymer sheet, a polymer sheet for a gap filler, and a third polymer sheet so that they are arranged in this order: the functional film, the first polymer sheet, the polymer sheet for a gap filler, and the third polymer sheet. The interlayer film for laminated glass of the seventh embodiment of the present invention can be produced, for example, by a production method including a step of laminating a second polymer sheet, a functional film, a first polymer sheet, a functional film, a third polymer sheet, and a polymer sheet for a gap filler so that they are arranged in this order: the second polymer sheet, the functional film, the first polymer sheet, the functional film, the third polymer sheet, and the polymer sheet for a gap filler.

[0092] Then, after laminating at least the functional film, the first polymer sheet, and the polymer sheet for the gap filler as described above, the functional film, the first polymer sheet, and the polymer sheet for the gap filler can be integrated by, for example, thermocompression bonding using a heat press.

[0093] Furthermore, when surfaces 2 and 3 are uneven, the unevenness may be formed on the surface of a polymer sheet, such as the first polymer sheet, the gap filler polymer sheet, the second polymer sheet, or the third polymer sheet, and then the polymer sheet is laminated to form the unevenness on the surface of the interlayer film for laminated glass. Alternatively, the unevenness may be formed on the surface of the interlayer film for laminated glass after the polymer sheets are laminated to form the interlayer film for laminated glass. As mentioned above, the method for forming the unevenness on the surface of the polymer sheet or the interlayer film for laminated glass is not particularly limited, and examples include lip embossing, embossing roll, and calender roll methods.

[0094] [Laminated Glass] The laminated glass of the present invention comprises a pair of glass plates and the interlayer film for laminated glass of the present invention provided between the pair of glass plates.

[0095] (Glass Plate) The laminated glass of the present invention may be any of glass plates, inorganic glass, and organic glass, but inorganic glass is preferred.The inorganic glass is not particularly limited, but includes clear glass, float glass, tempered glass, colored glass, polished glass, patterned glass, wired glass, lined glass, ultraviolet absorbing glass, infrared reflecting glass, infrared absorbing glass, green glass, etc.In addition, organic glass generally used is what is called resin glass, and includes various organic glass plates such as polycarbonate plate, (meth)acrylic plate such as polymethyl methacrylate plate, polyester plate such as acrylonitrile styrene copolymer plate, acrylonitrile butadiene styrene copolymer plate, polyethylene terephthalate plate, fluorine-based resin plate, polyvinyl chloride plate, chlorinated polyvinyl chloride plate, polypropylene plate, polystyrene plate, polysulfone plate, epoxy resin plate, phenolic resin plate, unsaturated polyester resin plate, polyimide resin plate, etc.The organic resin plate may be subjected to appropriate surface treatment.

[0096] The pair of glass plates used in the laminated glass of the present invention may be made of the same material or different materials. For example, one may be inorganic glass and the other organic glass, but it is preferable that both of the pair of glass plates are inorganic glass or organic glass. The thickness of each glass plate of the pair of glass plates is not particularly limited, but is, for example, about 0.1 to 15 mm, preferably 0.5 to 5 mm. The thicknesses of the pair of glass plates may be the same or different.

[0097] (Layer Structure of Laminated Glass) Next, the layer structure of laminated glass will be described in detail with reference to the drawings and embodiments. In the present invention, laminated glass may include a polymer sheet 80 between a pair of glass sheets in addition to the interlayer film for laminated glass of the present invention. For example, as shown in FIG. 11 , in a first embodiment of the present invention, laminated glass 100 may include a pair of glass sheets 60, 70, an interlayer film for laminated glass 1 of the first embodiment of the present invention, and a polymer sheet 80 on the side of the functional film 10 of the interlayer film 1 opposite to the side on which the first polymer sheets 20a, 20b are provided. Although the laminated glass 100 shown in FIG. 11 includes one polymer sheet 80, two or more polymer sheets may be used. Of course, in the present invention, laminated glass may include only the interlayer film for laminated glass of the present invention between a pair of glass sheets. For example, as shown in FIG. 12 , in the second embodiment of the present invention, a laminated glass 100A may be formed by providing an interlayer film 1B for laminated glass according to the second embodiment of the present invention between a pair of glass plates 60, 70, and bonding the pair of glass plates 60, 70 together only via the interlayer film 1B.

[0098] (Method for producing laminated glass) The laminated glass of the present invention may be produced by a method in which an interlayer film for laminated glass is placed between a pair of glass plates and then pressed together to obtain laminated glass.

[0099] In the above-described manufacturing method, first, two glass plates and the interlayer film for laminated glass of the present invention are prepared, and then the interlayer film for laminated glass is placed between the pair of glass plates and bonded together to form a laminated glass.

[0100] Alternatively, the laminated glass of the present invention may be produced by preparing a member constituting the interlayer film for laminated glass of the present invention, placing the member constituting the interlayer film for laminated glass of the present invention between a pair of glass plates, and bonding them together by pressure.

[0101] The lamination may be performed in a vacuum bag, in an autoclave under low temperature conditions, in a vacuum laminator, or in a press other than these, but among these, it is preferable to perform the lamination in a vacuum bag. Furthermore, before the lamination, temporary pressure bonding may be performed using a rubber roll or the like.

[0102] In this manufacturing method, the lamination is preferably carried out under low-temperature conditions, specifically, pressure bonding at a temperature of 110° C. or less. The lamination is also preferably carried out under low temperature and low pressure, specifically, pressure bonding at a temperature of 110° C. or less and a pressure of 1.0 MPa or less. By carrying out the lamination under such low-temperature and low-pressure conditions, the function of the functional film can be prevented from deteriorating or being deactivated.

[0103] The temperature during lamination is preferably 100°C or lower from the viewpoint of more reliably preventing deterioration or deactivation of the functional film, and preferably 60°C or higher, more preferably 70°C or higher, from the viewpoint of preventing the generation of residual air and bubbles. The pressure during lamination is preferably 1.2 MPa or lower from the viewpoint of more reliably preventing deterioration or deactivation of the functional film. When lamination is performed under negative pressure, such as when using a vacuum bag, the pressure may be, for example, 0.095 MPa or lower, preferably 0.08 MPa or lower, and preferably 0.06 MPa or lower. The lower limit of the pressure during lamination is not particularly limited, but when lamination is performed under pressure, such as in an autoclave, the pressure is preferably 0.5 MPa or higher, more preferably 0.7 MPa or higher. When lamination is performed under negative pressure, such as when using a vacuum bag, the pressure is preferably 0.001 MPa or higher, more preferably 0.005 MPa or higher. The time for lamination at the above temperature and pressure is not particularly limited, but is, for example, 5 to 120 minutes, preferably 10 to 60 minutes.

[0104] The laminated glass of the present invention can be used for various applications without any particular limitation. For example, the laminated glass of the present invention is used as window glass for various vehicles such as automobiles and trains, ships, and airplanes, various buildings such as buildings, condominiums, detached houses, halls, and gymnasiums, machine tools for cutting and polishing, construction machines such as shovels and cranes, and partitions inside various vehicles and buildings. Among these, vehicle applications such as automobiles are preferred, and it is preferably used as window glass for vehicles. Furthermore, the laminated glass of the present invention may be used for various display applications, for example, when a display device is constructed using laminated glass members. For display applications, the above-mentioned window glass or partition may be used as a display. Furthermore, the laminated glass may be used as a cover glass for various displays, for example, and may be applied to an in-vehicle display.

[0105] The present invention will be explained in more detail below using examples, but the present invention is not limited to these examples.

[0106] The methods for measuring various physical properties are as follows: <Evaluation of interlayer film for laminated glass> 1. Surface roughness The surface roughness (R ｚｊｉｓ９４ ) and the surface roughness (R ｚｊｉｓ９４ ) was measured by the method described in the above specification.

[0107] 2. Thickness The thickness of the obtained interlayer film for laminated glass was measured with a thickness meter and evaluated according to the following criteria: A: 1≦T1 / T2≦1.05 or 1≦T2 / T1≦1.05 B: 1.05<T1 / T2≦1.1 or 1.05<T2 / T1≦1.1 C: T1 / T2>1.1 or T2 / T1>1.1 T1: Thickness corresponding to the center position of the functional film in the interlayer film for laminated glass (see Figure 13) T2: Thickness at the center position of the interlayer film for laminated glass where no functional film is present (see Figure 13)

[0108] 3. Voids The cross section of the obtained interlayer film for laminated glass was observed under a microscope and evaluated according to the following criteria: A: Voids of 0 to 3 mm exist at the edge of the functional film. B: Voids of 3 to 5 mm exist at the edge of the functional film. C: Voids of more than 5 mm exist at the edge of the functional film.

[0109] <Evaluation of Laminated Glass> 1. Cracks The obtained laminated glass was visually observed and rated according to the following criteria: A: No cracks in any of the five glass sheets. B: Cracks in one of the five glass sheets. C: Cracks in two or more of the five glass sheets.

[0110] 2. Foaming The obtained laminated glass was heated in an oven at 140°C for 2 hours. Then, after removing from the oven and allowing it to cool for 3 hours, the appearance of the laminated glass was visually observed and the occurrence of foaming (bubbles) in the area where the functional film was present and around the edges of the functional film was evaluated according to the following criteria: A: No foaming (bubbles) in any of the five glass sheets, or foaming (bubbles) present in one glass sheet. B: Foaming (bubbles) present in two or three of the five glass sheets. C: Foaming (bubbles) present in four or more of the five glass sheets.

[0111] Example 1 (Preparation of Interlayer Film for Laminated Glass) A PDLC film (200 mm long x 200 mm wide x 385 μm thick) (A1) was prepared as the functional film 10. A PVB sheet (305 mm long x 305 mm wide x 380 μm thick) (B1) was prepared as the first polymer sheet 20a. A PVB sheet (305 mm long x 305 mm wide x 380 μm thick) (B2) was prepared as the second polymer sheet 40. A PVB sheet (305 mm long x 305 mm wide x 380 μm thick) (C1) was prepared as the gap filler polymer sheet 30, and an opening (201 mm long x 201 mm wide) was provided in the center (see FIG. 15(a)). These were aligned at the center lengthwise and widthwise and stacked in the order shown in FIG. 14(a) to obtain a laminate. Release sheets were placed on both sides of the obtained laminate, and the laminate was heated and decompressed by vacuum forming at a temperature of 90°C and a gauge pressure of -900 mbar, and the three PVB sheets were integrated by thermocompression bonding to obtain an interlayer film for laminated glass of Example 1 with a PDLC film embedded therein. An EPDM rubber sheet was used as the release sheet for thermocompression bonding. The surface roughness (R ｚｊｉｓ９４ The surface of the interlayer film for laminated glass was embossed so that the thickness of the laminated glass was 40 μm.

[0112] (Preparation of Laminated Glass) The obtained interlayer film was sandwiched between two transparent glass plates (300 mm long × 300 mm wide × 2 mm thick), and these were integrated using an autoclave under conditions of 140°C, 10 MPa (gauge pressure), and 30 minutes to obtain the laminated glass of Example 1. The obtained laminated glass was evaluated based on the above evaluation criteria.

[0113] Example 2 Four PVB sheets (253 mm long × 52 mm wide × 380 μm thick) were prepared and arranged so that the outer periphery was 305 mm long × 305 mm wide and the opening was 201 mm long × 201 mm wide (see FIG. 15( b)), to obtain a polymer sheet for gap fillers 30 (C1). Except for this, the interlayer film for laminated glass and laminated glass of Example 2 were obtained in the same manner as in Example 1.

[0114] Example 3 An interlayer film for laminated glass and a laminated glass of Example 3 were obtained in the same manner as in Example 1, except that a PVB sheet (length 305 mm × width 305 mm × thickness 200 μm) (B3) was further prepared as the third polymer sheet 50 and laminated in the order shown in FIG. 14( b).

[0115] [Example 4] Surface roughness (R ｚｊｉｓ９４ An interlayer film for laminated glass and a laminated glass of Example 4 were obtained in the same manner as in Example 1, except that the surface of the interlayer film for laminated glass was embossed so that the thickness of the laminated glass was 15 μm.

[0116] Example 5 An interlayer film for laminated glass and a laminated glass of Example 5 were obtained in the same manner as in Example 1, except that a heat reflective film (200 mm long x 200 mm wide x 110 μm thick) was prepared as the functional film 10 and a PVB sheet (305 mm long x 305 mm wide x 110 μm thick) (A1) was prepared as the polymer sheet for gap filler 30.

[0117] Example 6 An interlayer film for laminated glass and a laminated glass of Example 6 were obtained in the same manner as in Example 1, except that an SPD film (length 200 mm × width 200 mm × thickness 385 μm) (A2) was further prepared as the second functional film 10a, a PVB sheet (length 305 mm × width 305 mm × thickness 760 μm) (C1) was further prepared as the polymer sheet for gap filler 30, and a PVB sheet (length 305 mm × width 305 mm × thickness 380 μm) (B3) was further prepared as the third polymer sheet 20b, and these were laminated in the order shown in FIG. 14( c).

[0118] Comparative Example 1 An interlayer film for laminated glass and laminated glass of Comparative Example 1 were obtained in the same manner as in Example 1, except that the gap filler polymer sheet 30 was not used (see FIG. 14( d )).

[0119] Comparative Example 2 An interlayer film for laminated glass and a laminated glass of Comparative Example 2 were obtained in the same manner as in Example 1, except that the first polymer sheet 20a, the second polymer sheet 40, and the gap filler polymer sheet 30 were laminated as shown in FIG. 14( e).

[0120] The evaluation results are shown in Table 1.

[0121] In the interlayer films for laminated glass of Examples 1 to 6, the gap filler polymer sheet was provided on the side of the first polymer sheet opposite the functional film side, and thus void formation at the edge of the functional film was suppressed. On the other hand, the interlayer film for laminated glass of Comparative Example 1 was able to suppress void formation at the edge of the functional film, but because it did not have a gap filler polymer sheet, steps occurred in the thickness direction. Furthermore, in the interlayer film for laminated glass of Comparative Example 2, the gap filler polymer sheet was provided on the functional film side of the first polymer sheet, and therefore void formation at the edge of the functional film was not suppressed.

[0122] REFERENCE SIGNS LIST 1, 1A to 1K Interlayer film for laminated glass 10, 10a Functional film 20a, 20b First polymer sheet 20b, 30a to 30d Polymer sheet 40 Second polymer sheet 30, 30A, 30C to 30G, 30I, 30J Gap filler polymer sheet 50 Third polymer sheet 60, 70 Glass plate 80 Polymer sheet 100, 100A Laminated glass

Claims

1. An interlayer film for laminated glass comprising a functional film and one or more first polymer sheets provided on one side of the functional film, wherein, when projected in the thickness direction, the functional film is included in at least a region of the one or more first polymer sheets that is in contact with the functional film, and further comprising one or more polymer sheets for gap fillers provided on the side of the first polymer sheet opposite the functional film side.

2. The surface roughness (R ｚｊｉｓ９４ 2. The interlayer film for laminated glass according to claim 1, wherein the thickness of the interlayer is from 1 μm to 100 μm.

3. The interlayer film for laminated glass according to claim 1, further comprising a second polymer sheet provided on the other surface side of the functional film.

4. The surface roughness (R ｚｊｉｓ９４ 4. The interlayer film for laminated glass according to claim 3, wherein the thickness of the interlayer is from 1 μm to 100 μm.

5. The interlayer film for laminated glass according to claim 3, wherein, when projected in the thickness direction, the distance between the outer periphery of the first polymer sheet and the outer periphery of the polymer sheet for gap filler is 0 mm or more and 10 mm or less, when projected in the thickness direction, the distance between the outer periphery of the second polymer sheet and the outer periphery of the polymer sheet for gap filler is 0 mm or more and 10 mm or less, when projected in the thickness direction, the distance between the outer periphery of the first polymer sheet and the outer periphery of the second polymer sheet is 0 mm or more and 10 mm or less, when projected in the thickness direction.

6. The interlayer film for laminated glass according to claim 1, wherein the polymer sheet for gap filler has an opening in a region overlapping with the functional film when projected in the thickness direction.

7. The interlayer film for laminated glass according to claim 6, wherein the polymer sheet for gap filler having the openings is composed of a plurality of polymer sheets arranged in a planar direction.

8. The interlayer film for laminated glass according to claim 6, wherein the distance between the inner periphery of the opening of the polymer sheet for gap filler and the outer periphery of the functional film is 5 mm or less over the entire periphery when projected in the thickness direction.

9. The interlayer film for laminated glass according to claim 1, wherein at least one of the first polymer sheet and the cap filler polymer sheet contains at least one thermoplastic resin selected from the group consisting of polyvinyl acetal resins and ethylene-vinyl acetate copolymer resins.

10. The interlayer film for laminated glass according to claim 1, wherein the functional film is a film having a function of absorbing or reflecting a specific light.

11. The interlayer film for laminated glass according to claim 1, wherein the functional film contains a polyethylene terephthalate resin.

12. The interlayer film for laminated glass according to claim 1, wherein the functional film is a P-polarized reflective film, a film for holograms, a heat ray reflective film, a light control film, a display element film, a transparent conductive film, a touch sensor film, a circuit film, a solar power generation film, or an electrically controllable film.

13. The interlayer film for laminated glass according to claim 3, wherein the second polymer sheet contains at least one thermoplastic resin selected from the group consisting of polyvinyl acetal resins and ethylene-vinyl acetate copolymer resins.

14. The interlayer film for laminated glass according to claim 1, further comprising a third polymer sheet provided on the surface of the gap filler polymer sheet opposite to the first polymer sheet.

15. The interlayer film for laminated glass according to claim 3, wherein the surface facing the gap filler polymer sheet and the surface facing the second polymer sheet have irregularities with a regular or random shape.

16. The interlayer film for laminated glass according to claim 3, wherein at least one of the surface facing the gap filler polymer sheet and the surface facing the second polymer sheet is protected with a protective release film.

17. A method for producing an interlayer film for laminated glass according to any one of claims 1 to 16, comprising a step of laminating a functional film, a first polymer sheet, and a polymer sheet for a gap filler so that the functional film, the first polymer sheet, and the polymer sheet for a gap filler are arranged in this order.

18. A laminated glass comprising a pair of glass plates and the interlayer film for laminated glass according to any one of claims 1 to 16 provided between the pair of glass plates.