Laminated glass structure and laminated film

Abstract

The present disclosure provides a laminated glass structure that can exhibit a function derived from a functional layer such as a dimming film, has good appearance, and has high safety. The present disclosure also provides: an intermediate film for laminated glass, the intermediate film being capable of suitably providing a laminated glass structure having good appearance and high safety; and a laminated film including same. The laminated glass structure according to the present disclosure comprises, in the following order: a first glass plate; a first intermediate film; a functional layer; a second intermediate film; and a second glass plate. The first intermediate film has a creep compliance of 6.0 × 10-5 Pa-1 or more at 90°C per layer.

Description

Laminated glass structure and laminated film

[0001] The present disclosure relates to laminated glass constructions and laminate films.

[0002] Conventionally, laminated glass structures have been widely known, each comprising two glass sheets integrated together by an interlayer film interposed therebetween. Laminated glass structures are safe because they rarely scatter glass fragments even when broken by external impact, and are therefore widely used in vehicles such as automobiles, aircraft, ships, buildings, and the like.

[0003] In recent years, laminated glass structures have been required to have various functions, and for example, a functional layer such as a light control film may be disposed between two glass sheets. Patent Document 1 discloses a laminated glass having an interlayer film and a light control element encapsulated in the interlayer film between two glass sheets.

[0004] International Publication No. 2022 / 153998

[0005] Laminated glass structures are generally manufactured by placing an interlayer between two glass plates, followed by a preliminary degassing process, followed by an autoclave process in which the glass plates and the interlayer are pressure-bonded under high-temperature and high-pressure conditions, such as a temperature of about 130 to 140°C and a pressure of about 1.3 MPa. However, when a functional layer such as a light-control film is further placed between the two glass plates, the functional layer is likely to have complex steps (thickness differences) due to the inclusion of electronic wiring, occlusion printed areas, etc., and pressure unevenness during pressure bonding. Therefore, air remains or bubbles are generated between the interlayer and the glass plates or functional layer during pressure bonding, resulting in insufficient transparency in the obtained laminated glass structure, distortion or wrinkles in the functional layer, and distortion or warping of the obtained laminated glass structure, resulting in an unsatisfactory appearance.

[0006] In laminated glass structures including a functional layer such as a light control film, a frame-shaped intermediate layer (also referred to as a gap filler) is disposed around the periphery of the functional layer for the purpose of protecting the edges of the functional layer from the external environment, and this is sandwiched between a pair of intermediate layers, which is then further sandwiched between a pair of glass plates (see, for example, Patent Document 1). If a laminated glass structure including a functional layer is manufactured without using a gap filler, for example, from the perspective of improving work efficiency, there are concerns that air may remain or bubbles may form, resulting in an unsatisfactory appearance of the laminated glass structure and that the impact resistance may be lower than when a gap filler is used. Furthermore, if a laminated glass structure including a functional layer is manufactured without using a gap filler, stress may easily remain at the edges during pressure bonding, and the layer interface may be more likely to peel off.

[0007] Furthermore, since the functional layer is vulnerable to heat and pressure, when a glass plate and an interlayer film having the functional layer are pressure-bonded under normal high-temperature and high-pressure conditions, the functional layer may deteriorate or become inactive. In particular, when the functional layer contains a guest-host liquid crystal (GHLC), temperature and pressure changes during pressure bonding and thermal shrinkage of the interlayer film can cause color unevenness (also known as liquid crystal unevenness) in the resulting laminated glass structure, making it unsuitable for practical use. On the other hand, pressure bonding at low temperatures is likely to result in residual air or bubbles, and in this case too, a laminated glass structure suitable for practical use cannot be obtained.

[0008] The present disclosure has been made in view of the above-described current situation, and aims to provide a laminated glass structure that can exhibit the functions derived from a functional layer such as a light control film, has a good appearance, and is highly safe. Another aim of the present disclosure is to provide an interlayer film for laminated glass, or a laminate film including the interlayer film, that can suitably provide a laminated glass structure that has a good appearance and is highly safe.

[0009] The present inventors conducted extensive research into laminated glass structures including a functional layer such as a light control film and found that, in a laminated glass structure including a first glass sheet, a first interlayer film, a functional layer, a second interlayer film, and a second glass sheet in this order, if at least one of the interlayer films has a predetermined creep characteristic, residual air and foaming during pressure bonding can be suppressed without the use of a gap filler, resulting in a laminated glass structure with a good appearance. Such a laminated glass structure can optimally exhibit the effects inherent to the functional layer, and also exhibits impact resistance comparable to that of a structure using a gap filler. Even if the glass structure is broken, scattering and penetration of glass fragments are suppressed, making it safe. In other words, the laminated glass structure can exhibit the functions inherent to the functional layer, is sufficiently suppressed in terms of deflection and distortion, has a good appearance, and is highly safe. Thus, the present inventors have completed the laminated glass structure and the like of the present disclosure. Specifically, the present disclosure relates to the following laminated glass structures and the like.

[0010] Disclosure 1-1 provides a glass sheet having, in this order, a first glass sheet, a first interlayer film, a functional layer, a second interlayer film, and a second glass sheet, wherein the first interlayer film has a creep compliance of 6.0 × 10 at 90°C per layer. －５ Pa －１ Disclosure 1-2 is a laminated glass structure in which the creep compliance per layer at 90°C is 8.0 × 10 or more. －５ Pa －１ Above 5.0 x 10 －４ Pa －１The laminated glass structure of Disclosure 1-1 is as follows: Disclosure 1-3 is the laminated glass structure of Disclosure 1-1 or 1-2, in which the first interlayer film contains a thermoplastic resin. Disclosure 1-4 is the laminated glass structure of any of Disclosures 1-1 to 1-3, in which the first interlayer film contains a polyvinyl acetal resin. Disclosure 1-5 is the laminated glass structure of Disclosure 1-4, in which the polyvinyl acetal resin has a weight-average molecular weight of 220,000 to 310,000. Disclosure 1-6 is the laminated glass structure of any of Disclosures 1-3 to 1-5, in which the first interlayer film further contains a plasticizer.

[0014] Disclosure 1-7 is the laminated glass structure of Disclosure 1-6, wherein the plasticizer is at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives in which some of the hydrogen atoms of the terminal hydroxyl groups of these are substituted with alkyl groups. Disclosure 1-8 is the laminated glass structure of any of Disclosures 1-1 to 1-7, wherein the functional layer is at least one selected from the group consisting of a light control film and a display element film. Disclosure 1-9 is the laminated glass structure of any of Disclosures 1-1 to 1-8, wherein the functional layer is a light control film, and the light control film comprises at least one selected from the group consisting of a polymer dispersed liquid crystal (PDLC), a guest-host liquid crystal (GHLC), a suspended particle device (SPD), an electrochemical device, and an electrophoretic film device. Disclosure 1-10 is a laminated film comprising the first interlayer film, the functional layer, and a second interlayer film, which is provided in the laminated glass structure of any one of Disclosures 1-1 to 1-9. Disclosure 1-11 is a film comprising the first interlayer film, which is provided in the laminated glass structure of any one of Disclosures 1-1 to 1-9. Disclosure 1-12 is a laminated glass structure of any one of Disclosures 1-1 to 1-9, which is produced without using a gap filler.

[0011] The present inventors have also conducted extensive research into laminated glass structures including a light control film and have found that a laminated glass structure including a first glass plate, a first interlayer film, a light control film, a second interlayer film, and a second glass plate in this order, in which each component has a curved shape with convex portions in the same direction, and in which the thickness ratio of the region (a) of the laminated glass structure not including the light control film to the central region (b) of the region including the light control film is within a predetermined range when viewed from the thickness direction, can be obtained without requiring a gap filler and without impairing the function of laminated glass. Such a laminated glass structure can optimally exhibit the effects inherent to the light control film, has high impact resistance, and is safe because it prevents glass fragments from scattering or penetrating even if broken. In other words, the laminated glass structure can effectively exhibit the functions inherent to the light control film without using a gap filler, has a good appearance, and is highly safe. Thus, the present inventors have completed the laminated glass structure and the like of the present disclosure. That is, the present disclosure also relates to the following laminated glass structures and the like.

[0012] Disclosure 2-1 is a laminated glass structure comprising, in this order, a first glass plate, a first interlayer film, a light control film, a second interlayer film, and a second glass plate, wherein the first glass plate, the first interlayer film, the light control film, the second interlayer film, and the second glass plate are curved so as to have convex portions in the same direction, and the absolute value |a-b| of the difference between the thickness (a) of a region of the laminated glass structure that does not have the light control film and the thickness (b) of a central portion of the region that has the light control film, divided by the thickness (c) of the light control film, (|a-b| / c), is 0.1 to 0.5. Disclosure 2-2 is the laminated glass structure of Disclosure 2-1, wherein the first interlayer film contains a thermoplastic resin. Disclosure 2-3 is the laminated glass structure of Disclosure 2-1 or 2-2, wherein the first interlayer film contains a polyvinyl acetal resin. Disclosure 2-4 is the laminated glass structure of Disclosure 2-3, wherein the polyvinyl acetal resin has a weight-average molecular weight of 220,000 to 310,000. Disclosure 2-5 is the laminated glass structure of any one of Disclosures 2-2 to 2-4, wherein the first interlayer film further contains a plasticizer. Disclosure 2-6 is the laminated glass structure of Disclosure 2-5, wherein the thickness of the edge of the laminated glass structure is 99% or less of the thickness of the center of the laminated glass structure taken as 100%, and the plasticizer is at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives thereof in which some of the hydrogen atoms of the terminal hydroxyl groups are substituted with alkyl groups. Disclosure 2-7 is the laminated glass structure of any one of Disclosures 2-1 to 2-6, wherein the light control film comprises at least one selected from the group consisting of a polymer dispersed liquid crystal (PDLC), a guest-host liquid crystal (GHLC), a suspended particle device (SPD), an electrochromic device, and an electrophoretic film device. Disclosure 2-8 is the laminated glass structure of any one of Disclosures 2-1 to 2-6, wherein the first interlayer film has a creep compliance of 6.0 × 10 per layer at 90°C. －５ Pa －１The laminated glass structure of any one of Disclosures 2-1 to 2-7 is as described above. Disclosure 2-9 is the laminated glass structure of any one of Disclosures 2-1 to 2-8, in which the ratio (a / b) of the thickness (a) to the thickness (b) is 0.9 to 1.0. Disclosure 2-10 is a laminated film comprising the first interlayer film, the light control film, and a second interlayer film, which is included in the laminated glass structure of any one of Disclosures 2-1 to 2-9.

[0013] The present inventors have also conducted extensive research into laminated glass structures including a GHLC film and have found that, in a laminated glass structure including a first glass sheet, a first interlayer film, a GHLC film, a second interlayer film, and a second glass sheet in this order, if at least one of the interlayer films satisfies a predetermined creep characteristic, residual air and foaming during compression bonding can be suppressed, even without an autoclave process under high temperature and high pressure conditions, thereby producing a laminated glass structure with a good appearance. Such a laminated glass structure can optimally exhibit the functions inherent to the GHLC film without losing them, and color unevenness is sufficiently suppressed. In other words, the laminated glass structure can exhibit the functions inherent to the GHLC film without losing them, has a good appearance, and is highly safe. Thus, the present inventors have completed the laminated glass structure and the like of the present disclosure. That is, the present disclosure also relates to the following laminated glass structures and the like.

[0014] Disclosure 3-1 provides a glass sheet having, in this order, a first glass sheet, a first interlayer film, a GHLC film, a second interlayer film, and a second glass sheet, wherein the first interlayer film has a creep compliance of 6.0 × 10 at 90°C per layer. －５ Pa －１This is a laminated glass structure as described above. Disclosure 3-2 is the laminated glass structure of Disclosure 3-1, wherein the first interlayer film contains a thermoplastic resin. Disclosure 3-3 is the laminated glass structure of Disclosure 3-1 or 3-2, wherein the first interlayer film contains a polyvinyl acetal resin. Disclosure 3-4 is the laminated glass structure of Disclosure 3-3, wherein the polyvinyl acetal resin has a weight-average molecular weight of 220,000 to 310,000. Disclosure 3-5 is the laminated glass structure of any of Disclosures 3-2 to 3-4, wherein the first interlayer film further contains a plasticizer. Disclosure 3-6 is the laminated glass structure of Disclosure 3-5, wherein the plasticizer is at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives thereof in which some of the hydrogen atoms of the terminal hydroxyl groups are substituted with alkyl groups. Disclosure 3-7 is a laminated film comprising the first interlayer film, the GHLC film, and a second interlayer film, which is included in the laminated glass structure of any of Disclosures 3-1 to 3-6. Disclosure 3-8 is a film comprising the first interlayer film, which is included in the laminated glass structure of any of Disclosures 3-1 to 3-6. Disclosure 3-9 is the laminated glass structure of any of Disclosures 3-1 to 3-6, which is produced without using a gap filler.

[0015] The present inventors also conducted extensive research into interlayer films for laminated glass and discovered that when the interlayer film contains a polyvinyl acetal resin and has an embossing remaining distance within a predetermined range, it exhibits high adhesion to various substrates, such as glass sheets. By using such an interlayer film for laminated glass, residual air and foaming can be suppressed during pressure bonding to glass sheets, etc., without the need for an autoclave process under high temperature and high pressure conditions or the use of a gap filler, thereby efficiently producing laminated glass structures with good appearance. Furthermore, when a functional layer is laminated onto the interlayer film for laminated glass to produce a laminated glass structure, the laminated glass structure can effectively exhibit the effects derived from the functional layer. In other words, the interlayer film for laminated glass has excellent adhesion to various substrates, and can suitably produce laminated glass structures with good appearance and high safety. Thus, the present inventors have perfected the interlayer film for laminated glass and the like of the present disclosure. That is, the present disclosure also relates to the following interlayer films for laminated glass.

[0016] Disclosure 4-1 provides an interlayer film for laminated glass that contains a polyvinyl acetal resin, has at least one surface with an uneven shape, and has an embossing remaining distance of less than 27 mm, as calculated by the following method. <Method for calculating the remaining embossing distance> Two float glass sheets measuring 300 mm long, 300 mm wide, and 3 mm thick and conforming to JIS R3202 (2011) are prepared. Two interlayer films for laminated glass measuring 300 mm long, 300 mm wide, and 760 μm thick are also prepared, along with one polyethylene terephthalate (PET) film measuring 200 mm long, 200 mm wide, and 188 μm thick. The float glass sheets, interlayer film for laminated glass, PET film, interlayer film for laminated glass, and float glass sheets are then laminated in this order, with the centroids of each component aligned in a plan view. The resulting laminate (referred to as "Laminate 1") is degassed for 5 minutes at a vacuum pressure of 4 kPa. When the transmittance (referred to as transmittance B) is measured from one end of the laminate 1 to the other end opposite the end along a center line passing through the centroid of the PET film when the laminate 1 is viewed in plan after degassing, the distance between a first portion where the ratio (B / A) of the transmittance A to the transmittance B first becomes 0.75 or less and the end of the region where the PET film is disposed that is closest to the first portion is measured, and this distance is defined as the remaining embossing distance. Transmittance A is the maximum value of the transmittance of the laminate 3 described below. Two sheets each of the same float glass sheet and interlayer film for laminated glass used to obtain the laminate 1 are prepared, and then the float glass sheet, the interlayer film for laminated glass, the interlayer film for laminated glass, and the float glass sheet are laminated in this order so that the centroids of each component coincide in plan view. This laminate (referred to as laminate 2) is placed in a vacuum laminator "LAMINATOR 0505S" manufactured by Nisshinbo Mechatronics Inc. and degassed for 5 minutes at a vacuum pressure of 4 kPa. Next, while still degassed, laminate 2 is pressurized up to 100 kPa using a medium-speed press (pressure increase rate: 2 kPa / s) and then held at 100 kPa for 3 minutes. Thereafter, pressure bonding is performed for 20 minutes using an autoclave at 140°C and 1.3 MPa to obtain laminate 3.

[0017] Disclosure 4-2 is the interlayer film for laminated glass of Disclosure 4-1, wherein the polyvinyl acetal resin has a weight-average molecular weight of 220,000 to 310,000. Disclosure 4-3 is the interlayer film for laminated glass of Disclosure 4-1 or 4-2, further comprising a plasticizer. Disclosure 4-4 is the interlayer film for laminated glass of Disclosure 4-3, wherein the plasticizer is at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives thereof in which some of the hydrogen atoms of the terminal hydroxyl groups are substituted with alkyl groups. Disclosure 4-5 is the interlayer film for laminated glass according to any one of Disclosures 4-1 to 4-4, wherein at least one surface has an uneven shape, the uneven surface has a surface roughness (RzJIS94) of 10 to 80 μm as measured in accordance with JIS B0601 (1994), and the uneven surface has a surface roughness (Rc) of 10 to 40 μm as measured in accordance with JIS B0601 (2013). Disclosure 4-6 is a laminated film having a structure in which the interlayer film for laminated glass according to any one of Disclosures 4-1 to 4-5 and a functional layer are laminated. Disclosure 4-7 is the laminated film according to Disclosure 4-6, wherein the functional layer is sandwiched between a first interlayer film and a second interlayer film, and at least one of the first interlayer film and the second interlayer film is the interlayer film for laminated glass according to any one of Disclosures 4-1 to 4-5.

[0013] The present disclosure 4-8 is the laminate film of disclosure 4-6 or 4-7, wherein the functional layer is at least one selected from the group consisting of a light control film and a display element film.

[0014] The present disclosure 4-9 is the laminate film of any of disclosures 4-6 to 4-8, wherein the functional layer is a light control film, and the light control film comprises at least one selected from the group consisting of a polymer dispersed liquid crystal (PDLC), a guest-host liquid crystal (GHLC), a suspended particle device (SPD), an electrochemical device, and an electrophoretic film device.

[0015] The present disclosure 4-10 is a laminated glass structure having a structure in which the laminate film of any of disclosures 4-6 to 4-9 is sandwiched between a pair of glass plates.

[0018] The present inventors further conducted extensive research into interlayer films for laminated glass and discovered that, when the interlayer film contains a polyvinyl acetal resin and has an exposed film area calculated by a predetermined method within a predetermined range, residual air and foaming are suppressed during pressure bonding to glass plates or the like, thereby enabling efficient production of laminated glass structures with good appearance, even without an autoclave process under high-temperature and high-pressure conditions. Furthermore, when a laminated glass structure is obtained by laminating a functional layer on the interlayer film for laminated glass, the laminated glass structure can effectively exhibit the effects inherent to the functional layer. For example, even when a GHLC film is used as the functional layer and an interlayer film for laminated glass is laminated on the GHLC film, the resulting laminated glass structure can favorably exhibit the functions inherent to the GHLC film without losing them, and liquid crystal unevenness is sufficiently suppressed. In other words, the interlayer film for laminated glass can favorably provide a laminated glass structure with good appearance and high safety. Thus, the present inventors have perfected the interlayer film for laminated glass and the like of the present disclosure. That is, the present disclosure also relates to the following interlayer films for laminated glass.

[0019] Disclosure 5-1 relates to an interlayer film for laminated glass, which contains a polyvinyl acetal resin and has an exposed film area of ​​90% or less, calculated by the following method. <Method for calculating exposed film area> As a sample, one interlayer film for laminated glass measuring 30 cm long x 15 cm wide is prepared and maintained at constant temperatures of 23°C and 28% RH for 4 hours. Separately, two float glass sheets measuring 30 cm long x 15 cm wide x 3 mm thick and conforming to JIS R3202 (2011) are prepared. The glass and the sample are then laminated so that the tin side of the glass contacts the sample and the sample is positioned between the two sheets of glass. The resulting laminate is pre-pressed using a heated roll at 170°C. The pre-pressed laminate is placed in an autoclave and heated to 90°C at 2°C / min. During heating, the pressure is reduced to 0.1 MPa when the temperature reaches 40°C. After reaching 90°C, the sample is maintained at this temperature for 20 minutes and cooled at a rate of 2°C / min. When the temperature reaches 40°C, the pressure is returned to normal pressure. The resulting optical laminate is left standing for 16 hours in an environment at a temperature of -18°C±0.6°C, and then the optical laminate, fixed at a 45° inclination angle, is struck 72 times per minute with a hammer whose spring screw is adjusted so that the impact force at the top dead center of the stroke is 10.5±0.5 kg. The strikes are performed so that the hammer strikes the optical laminate horizontally. The strikes are performed from the bottom of the optical laminate: 13 strikes at 11.5 mm intervals in the horizontal direction (150 mm stroke) and 10 strikes at 9 mm intervals in the vertical direction (90 mm stroke), for a total of 130 strikes. Images of the optical laminate after the strikes are taken, and the area percentage (area %) of the sample where the glass is peeled off and exposed from the optical laminate is analyzed. Disclosure 5-2 is the interlayer film for laminated glass of Disclosure 5-1, wherein the polyvinyl acetal resin has a weight average molecular weight of 220,000 to 310,000. Disclosure 5-3 is the interlayer film for laminated glass of Disclosure 5-1 or 5-2, further comprising a plasticizer.Disclosure 5-4 is the interlayer film for laminated glass according to Disclosure 5-3, wherein the plasticizer is at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives thereof in which some of the hydrogen atoms of the terminal hydroxyl groups are substituted with alkyl groups. Disclosure 5-5 has a creep compliance per layer at 90°C of 6.0 x 10. －５ Pa －１ The present disclosure is an interlayer film for laminated glass according to any one of Disclosures 5-1 to 5-4. Disclosure 5-6 is an interlayer film for laminated glass according to any one of Disclosures 5-1 to 5-5, wherein at least one surface of the interlayer film for laminated glass has an uneven shape. Disclosure 5-7 is a laminate film having a structure in which the interlayer film for laminated glass according to any one of Disclosures 5-1 to 5-6 and a functional layer are laminated. Disclosure 5-8 is the laminate film according to Disclosure 5-7, having a structure in which the functional layer is sandwiched between a first interlayer film and a second interlayer film, and at least one of the first interlayer film and the second interlayer film is an interlayer film for laminated glass according to any one of Disclosures 5-1 to 5-6. Disclosure 5-9 is the laminate film according to Disclosure 5-7 or 5-8, wherein the functional layer is at least one selected from the group consisting of a light control film, a display element film, and a solar cell element.

[0014] Disclosure 5-10 is the laminated film of any one of Disclosures 5-7 to 5-9, wherein the functional layer is a light control film, and the light control film comprises at least one selected from the group consisting of a polymer dispersed liquid crystal (PDLC), a guest-host liquid crystal (GHLC), a suspended particle device (SPD), an electrochromic device, and an electrophoretic film device. Disclosure 5-11 is a laminated glass structure having a structure in which the laminated film of any one of Disclosures 5-7 to 5-10 is sandwiched between a pair of glass plates. Disclosure 5-12 is the laminated glass structure of Disclosure 5-11, which is produced without using a gap filler.

[0020] The present disclosure has been made in view of the above-described current situation, and aims to provide a laminated glass structure that can exhibit the functions derived from a functional layer such as a light control film, has a good appearance, and is highly safe. Another aim of the present disclosure is to provide an interlayer film for laminated glass, or a laminate film including the interlayer film, that can suitably provide a laminated glass structure that has a good appearance and is highly safe.

[0021] Fig. 1 is a schematic diagram showing an example of a layer structure of a laminated glass structure. Fig. 2 is a schematic diagram showing the layer structure of a laminate 1 in Example 1 as viewed from the side. Fig. 3 is a schematic plan view of the laminate 1 in Example 1. Fig. 4 is a photograph taken from above of the laminate when the remaining embossing distance of a film 11 was measured.

[0022] The laminated glass structure and the like of the present disclosure are described below. The present disclosure is not limited to the contents described below, and appropriate design changes can be made within the scope of the configuration of the present disclosure. In addition, the embodiments disclosed below can be combined as appropriate. For example, a part of the embodiment shown in any of "1." to "5." below can be combined as appropriate with another embodiment of "1." to "5." below.

[0023] 1. Laminated Glass Construct, Film, and Laminated Film of the Present Disclosures 1-1 to 1-12 As described above, the laminated glass construct of the present disclosure 1-1 includes a first glass sheet, a first interlayer film, a functional layer, a second interlayer film, and a second glass sheet in this order, and the first interlayer film has a creep compliance of 6.0 × 10 at 90°C per layer. －５ Pa －１ Such a laminated glass structure can exhibit the functions inherent to the functional layer, is sufficiently suppressed from warping or distortion, has a good appearance, and is highly safe.

[0024] The laminated glass structures, films, laminated films, and the like according to Disclosures 1-1 to 1-12 will be described below.

[0025] [Layer structure] The laminated glass structure includes a first glass sheet, a first interlayer film, a functional layer, a second interlayer film, and a second glass sheet, in this order. The laminated glass structure may further include one or more optional layers between the layers, or may include two or more functional layers as described below.

[0026] A laminated glass structure includes a pair of glass sheets (i.e., a first glass sheet and a second glass sheet) and a pair of interlayer films (i.e., a first interlayer film and a second interlayer film) sandwiching a functional layer between them. For example, it is preferable that the first interlayer film is adhered to the first glass sheet and the functional layer, and the second interlayer film is adhered to the second glass sheet and the functional layer, and thus bond these together. This results in a unified structure of the pair of glass sheets, the pair of interlayer films, and the functional layer. Such a layer structure is represented by G1 / F1 / Z / F2 / G2 (see FIG. 1 ). G1 represents the first glass sheet, G2 represents the second glass sheet, F1 represents the first interlayer film, F2 represents the second interlayer film, and Z represents the functional layer. FIG. 1 is a schematic diagram showing an example of the layer structure of a laminated glass structure.

[0027] Although the above example illustrates an embodiment in which two interlayer films and one functional layer are provided between a pair of glass sheets, three or more interlayer films and two or more functional layers may be provided between the pair of glass sheets. In this case, it is preferable that the interlayer films and the functional layers are alternately arranged, and it is preferable that an interlayer film is provided at the position closest to each glass sheet. For example, when three or more interlayer films and two or more functional layers are provided between a pair of glass sheets, the layer structure of the laminated glass structure is preferably G1 / F3 / Z1 / F4 / Z2 / F5 / G2. Z1 and Z2 may be the same or different and represent functional layers. F3, F4, and F5 may be the same or different and represent interlayer films. At least one of the interlayer films F3, F4, and F5 may be the first interlayer film described above (i.e., an interlayer film whose creep compliance per interlayer film falls within a predetermined range), and the other interlayer films may be the second interlayer film described above.

[0028] [Glass Plates] The laminated glass structure has a first glass plate and a second glass plate. Each glass plate may be, for example, inorganic glass or organic glass, but is preferably inorganic glass. The first glass plate and the second glass plate may be made of the same material or different materials. For example, one of the first glass plate and the second glass plate may be inorganic glass and the other may be organic glass, but it is preferable that both the first glass plate and the second glass plate are inorganic glass or organic glass.

[0029] The inorganic glass is not particularly limited, but examples thereof include clear glass, float glass, tempered glass, colored glass, polished glass, patterned glass, wired glass, striped glass, ultraviolet absorbing glass, infrared reflecting glass, infrared absorbing glass, and green glass.

[0030] As the organic glass, what is generally called resin glass is used, and examples thereof include various organic glass plates such as polycarbonate plate, (meth)acrylic plate such as polymethyl methacrylate plate, acrylonitrile styrene copolymer plate, acrylonitrile butadiene styrene copolymer plate, polyester plate such as 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 resin plate may be subjected to a surface treatment or the like as appropriate.

[0031] The thickness of each glass plate is not particularly limited, but is preferably about 0.1 to 15 mm, more preferably 0.5 to 5 mm, for example. The thickness of each glass plate may be the same as or different from that of the first glass plate and the second glass plate.

[0032] Other members may be attached to each glass plate as necessary. For example, a functional member may be attached to at least one of the first and second glass plates, in which case various functions are imparted to the glass plate. The other members are preferably members constituting, for example, electronic devices or optical components, and more preferably members constituting display devices. Examples of display devices include liquid crystal display devices, organic EL display devices, LED display devices, and segment display devices, among which liquid crystal display devices are preferred. Examples of display devices include display panels using a glass plate as a substrate on which a display layer such as a liquid crystal layer or an organic EL layer, and light-emitting elements, etc. are provided. The glass plate as a substrate may also be used as the first and / or second glass plate. Each glass plate may also be laminated with various functional layers, such as a functional film (described below); a conductive layer constituting an electrode, sensor, etc.; an antireflection layer; or a hard coat layer.

[0033] [Interlayer film] The laminated glass structure has at least a pair of interlayer films arranged to sandwich the functional layer. One of the pair of interlayer films is referred to as a first interlayer film, and the other is referred to as a second interlayer film. The first interlayer film and the second interlayer film may have the same configuration or may be different from each other.

[0034] The first interlayer film and the second interlayer film may each be a single-layer film having a single-layer structure or a multilayer film having a multilayer structure. When the first interlayer film and / or the second interlayer film has multiple layers, the multiple layers may have the same structure or different structures. For example, the types and contents of the constituent materials (e.g., thermoplastic resins) of the multiple layers may be the same or different. When the first interlayer film has multiple layers, the number of layers is not particularly limited, but may be, for example, two or three. When the second interlayer film has multiple layers, the number of layers is not particularly limited, but may be, for example, two or three.

[0035] The first interlayer film has a creep compliance of 6.0 × 10 at 90 ° C. per layer. －５ Pa －１or more. Such an interlayer film has high fluidity under lamination conditions, so that a laminated glass structure can be suitably obtained even without disposing a gap filler around the functional layer. That is, when the interlayer film and the functional layer are disposed between a pair of glass plates and pressure-bonded, peeling at the layer interface and the generation of residual air or bubbles are sufficiently suppressed. Furthermore, even if this pressure-bonding is performed under low-temperature conditions, for example, residual air or bubbles are sufficiently suppressed. Furthermore, even if this pressure-bonding is performed under low-pressure conditions, for example, residual air or bubbles are sufficiently suppressed. Therefore, the laminated glass structure of the present disclosure has excellent transparency and a good appearance. The creep compliance is 7.5 × 10 －５ Pa －１ More preferably, it is 8.0 × 10 or more. －５ Pa －１ More preferably, it is 1.0 x 10 or more. －４ Pa －１ More preferably, it is 1.3 × 10 or more. －４ Pa －１ The upper limit of the creep compliance is 1.0×10 －３ Pa －１ Preferably, it is 7.0 x 10 or less. －４ Pa －１ More preferably, 5.0 x 10 －４ Pa －１ It is more preferable that the creep compliance is 6.0×10 or less. －５ Pa －１ Above 1.0 x 10 －３ Pa －１ Preferably, it is 7.5 × 10 or less. －５ Pa －１ Above 1.0 x 10 －３ Pa －１ More preferably, it is 8.0 × 10 or less. －５ Pa －１ Above 1.0 x 10 －３ Pa －１ More preferably, the creep compliance is 6.0×10 or less. －５ Pa －１ Above 7.0 x 10 －４ Pa －１More preferably, it is 6.0 × 10 or less. －５ Pa －１ Above 5.0 x 10 －４ Pa －１ More preferably, it is 8.0 × 10 or less. －５ Pa －１ Above 5.0 x 10 －４ Pa －１ More preferably, it is 1.0 x 10 or less. －４ Pa －１ Above 5.0 x 10 －４ Pa －１ It is particularly preferable that the value is 1.3 × 10 or less. －４ Pa －１ Above 5.0 x 10 －４ Pa －１ Most preferably, the following:

[0036] The creep compliance at 90°C per layer is determined as follows. <Method for Measuring Creep Compliance> A dynamic viscoelasticity measuring system "MCR702e MultiDrive" (purchased in 2023) manufactured by Anton Paar is used as the measuring device. Using this measuring device, a shear stress of 400 Pa is applied for 15 minutes at a measurement temperature of 90°C to a circular sample made from one layer of the interlayer, the sample having a diameter of 8 mm and a thickness of 0.76 mm, to obtain the creep compliance J(t). The value of the obtained creep compliance J(t) after 10 minutes has elapsed is defined as the "creep compliance at 90°C per layer" value.

[0037] Here, if the thickness of the sample (interlayer film) to be measured is less than 0.76 mm, several samples may be stacked and press-molded or the like to make the samples uniform in thickness, or if the physical properties of the sample change due to heat pressing, the sample may be measured at its original thickness without being pressed. Furthermore, if the sample thickness is thicker than 0.76 mm, the thickness may be made uniform by press molding or the like, or the sample may be measured at its original thickness. From the viewpoint of measurement accuracy, the measured sample thickness is preferably 0.3 mm or more, and preferably 3 mm or less.

[0038] When setting the sample in the measurement device, the gap at room temperature is set to a pressure of 5 to 10 N to ensure sufficient compression between the sample and the jig, and then the sample is heated to 140°C with the gap fixed. Two minutes after reaching 140°C, the temperature begins to decrease to the measurement temperature, and after reaching the measurement temperature, the temperature is maintained for two minutes before creep compliance measurement begins. Stainless steel parallel plates with a diameter of 8 mm are used as the measurement jig.

[0039] In the laminated glass structure of the present disclosure, it is sufficient that at least one (first interlayer) of a pair of interlayers arranged to sandwich the functional layer satisfies the creep compliance value. For example, when the first interlayer is a multilayer film, it is sufficient that at least one layer thereof satisfies the creep compliance value. However, considering the adhesion between the glass sheet and the first interlayer, it is preferable that the layer constituting the first interlayer adjacent to the glass sheet satisfies the creep compliance value. Furthermore, considering the adhesion between the first interlayer and the functional layer, it is preferable that the layer constituting the first interlayer adjacent to the functional layer satisfies the creep compliance value, and it is more preferable that all layers satisfy the creep compliance value.

[0040] From a similar viewpoint, it is preferable that the second interlayer film also satisfies the above creep compliance value. When the second interlayer film is a multilayer film, it is sufficient that at least one layer thereof satisfies the above creep compliance value, but, for example, in consideration of the adhesion between the glass plate and the second interlayer film, it is preferable that the layer constituting the second interlayer film that is adjacent to the glass plate satisfies the above creep compliance value, and in consideration of the adhesion between the second interlayer film and the functional layer, it is preferable that the layer constituting the second interlayer film that is adjacent to the functional layer satisfies the above creep compliance value, and it is more preferable that all layers satisfy the above creep compliance value.

[0041] The first interlayer film and / or the second interlayer film preferably have a glass transition temperature (Tg) of -10°C or higher. When the Tg is within this range, the penetration resistance and impact resistance are further improved. The Tg is more preferably 0°C or higher, even more preferably 10°C or higher, and particularly preferably 15°C or higher. The Tg is also preferably 50°C or lower. When the Tg is within this range, the adhesion to glass plates and the like is more likely to be improved. The Tg is more preferably 40°C or lower, even more preferably 30°C or lower.

[0042] The Tg of the interlayer film is determined by viscoelasticity measurement. Specifically, it can be determined, for example, as follows. <Tg Measurement Method> The test piece to be measured is stored for 12 hours in an environment of room temperature 23±2°C and humidity 25±5%. Next, viscoelasticity is measured using a TA Instruments viscoelasticity measuring device "ARES-G2". Using a parallel plate with a diameter of 8 mm as a jig, measurements are made under the following conditions: shear mode, temperature decrease from 100°C to -20°C at a rate of 3°C / min, frequency 1 Hz, and strain 1%. In the measurement results obtained, the peak temperature of the loss tangent is taken as the glass transition temperature Tg (°C).

[0043] (Thermoplastic Resin) The first interlayer film preferably contains a thermoplastic resin. The second interlayer film also preferably contains a thermoplastic resin. That is, each interlayer film preferably has a resin layer containing a thermoplastic resin. By adjusting the weight average molecular weight of the resin, the glass transition temperature of the resin, and / or the intermolecular interaction, etc., it becomes easy to adjust the creep compliance per layer within a predetermined range. When the first interlayer film or the second interlayer film is a multilayer film, it is preferable that at least the layer satisfying the creep compliance value is the resin layer. Note that each of the components contained in each interlayer film may be used alone or in combination of two or more.

[0044] Examples of thermoplastic resins include (meth)acrylic resins, polyvinyl acetal resins, polyvinyl alcohol resins, polyurethane resins (PU), ethylene-vinyl acetate copolymer resins (EVA), saponified ethylene-vinyl acetate copolymer (EVOH), ethylene-methacrylic acid copolymer resins, ionomer resins, isobutylene resins, styrene-isoprene copolymer resins, and styrene-butadiene copolymer resins. Among these, from the viewpoint of achieving both moist heat resistance and impact resistance, the thermoplastic resin is preferably polyvinyl acetal resins, polyurethane resins (PU), ethylene-vinyl acetate copolymer resins (EVA), saponified ethylene-vinyl acetate copolymer (EVOH), ethylene-methacrylic acid copolymer resins, ionomer resins, isobutylene resins, styrene-isoprene copolymer resins, and / or styrene-butadiene copolymer resins. Among these, the thermoplastic resin is more preferably polyvinyl acetal resin.

[0045] As described above, the resin layer preferably contains a polyvinyl acetal resin. That is, the first interlayer film preferably contains a polyvinyl acetal resin. The second interlayer film also preferably contains a polyvinyl acetal resin. By providing an interlayer film containing a polyvinyl acetal resin, the laminated glass structure has better impact resistance and also improves the adhesion of the interlayer film to various adherends (e.g., functional layers, glass plates, etc.). Polyvinyl acetal resins are described in detail below.

[0046] The polyvinyl acetal resin is obtained by acetalizing polyvinyl alcohol with an aldehyde. Each of the raw materials for the polyvinyl acetal resin may be used alone or in combination of two or more.

[0047] The aldehyde is not particularly limited, but for example, an aldehyde having 1 to 10 carbon atoms is preferably 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. Among these, the aldehyde is preferably n-butylaldehyde, n-hexylaldehyde, or n-valeraldehyde, and more preferably n-butylaldehyde. Therefore, the polyvinyl acetal resin is preferably a polyvinyl butyral resin.

[0048] Polyvinyl alcohol can be obtained by saponifying a polyvinyl ester such as polyvinyl acetate, etc. The degree of saponification of polyvinyl alcohol is generally 70 to 99.9 mol %.

[0049] The average degree of polymerization of polyvinyl alcohol is preferably 1,000 to 3,000. Use of such polyvinyl alcohol tends to result in a polyvinyl acetal resin having a preferred weight-average molecular weight, which will be described later. The average degree of polymerization of polyvinyl alcohol is more preferably 1,100 to 2,500, further preferably 1,200 to 2,000, and particularly preferably 1,300 to 1,700.

[0050] As the polyvinyl alcohol, two or more types of polyvinyl alcohols having different average degrees of polymerization may be used. In this case, it is preferable to produce the polyvinyl acetal resin using a mixture of two or more types of polyvinyl alcohols as a raw material.

[0051] When two or more types of polyvinyl alcohols are used, it is preferable to use, for example, a first polyvinyl alcohol having an average degree of polymerization of 1500 or more and a second polyvinyl alcohol having an average degree of polymerization of 1200 or less. The average degree of polymerization of the first polyvinyl alcohol is preferably 1500 to 3500, more preferably 1600 to 2500, and even more preferably 1600 to 2000. The average degree of polymerization of the second polyvinyl alcohol is preferably 200 to 1200, more preferably 300 to 900, and even more preferably 400 to 850.

[0052] When the first polyvinyl alcohol and the second polyvinyl alcohol are used in combination, their blending ratio is not particularly limited. For example, the blending amount of the second polyvinyl alcohol is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, even more preferably 5 to 35% by mass, and particularly preferably 10 to 30% by mass, relative to 100% by mass of the total amount of the first polyvinyl alcohol and the second polyvinyl alcohol.

[0053] The average degree of polymerization of polyvinyl alcohol is determined by a method conforming to JIS K6726 (1994) "Testing Method for Polyvinyl Alcohol." When two or more types of polyvinyl alcohol are used as raw materials, the average degree of polymerization of the polyvinyl alcohol can be estimated by calculation from the average degrees of polymerization of each polyvinyl alcohol.

[0054] The polyvinyl acetal resin preferably has a weight-average molecular weight of 100,000 to 300,000. This further improves the adhesion of the interlayer film to various substrates and the penetration resistance of the laminated glass structure. Furthermore, using a polyvinyl acetal resin having a weight-average molecular weight within the above range makes it easier to adjust the creep compliance per interlayer film layer within the above range. The lower limit of the weight-average molecular weight of the polyvinyl acetal resin is more preferably 180,000 or more, even more preferably 210,000 or more, particularly preferably 220,000 or more, and even more preferably 245,000 or more. The upper limit of the weight-average molecular weight of the polyvinyl acetal resin is more preferably 280,000 or less. The weight-average molecular weight of the polyvinyl acetal resin may be preferably 260,000 or less, and may be particularly preferably 250,000 or less. The weight-average molecular weight of the polyvinyl acetal resin is more preferably in the range of 180,000 to 280,000, even more preferably 210,000 to 280,000, even more preferably 220,000 to 280,000, and particularly preferably 245,000 to 280,000. In some cases, the weight-average molecular weight of the polyvinyl acetal resin is preferably 210,000 to 260,000, and in other cases, 220,000 to 250,000 is particularly preferred.

[0055] The weight-average molecular weight of a polyvinyl acetal resin can be determined, for example, by gel permeation chromatography using the following measurement method. <Method for Measuring Molecular Weight> A polyvinyl acetal resin is dissolved in an N-methyl-2-pyrrolidone solution to which lithium bromide has been added to make the concentration 10 mM, to obtain a solution having a polyvinyl acetal resin concentration of 0.05% by mass. The resulting solution is filtered using a syringe filter (Millex-LH 0.45 μm, manufactured by Merck) and then the molecular weight is measured using gel permeation chromatography (e2690, manufactured by Waters). The weight-average molecular weight (Mw) is then calculated using a molecular weight calibration curve prepared using monodisperse polystyrene standard samples. A Shodex GPC KF-806L (manufactured by Showa Denko KK) is used as the column, and an N-methyl-2-pyrrolidone solution to which lithium bromide has been added to make the concentration 10 mM is used as the eluent.

[0056] The hydroxyl group content of the polyvinyl acetal resin is preferably 15 mol% or more. This tends to improve the adhesion of the interlayer film to various substrates, and the resulting laminated glass structure has excellent penetration resistance and other properties. The hydroxyl group content of the polyvinyl acetal resin is preferably 38 mol% or less. This improves the flexibility of the interlayer film and prevents the resulting laminated glass structure from becoming too hard. Furthermore, when the hydroxyl group content of the polyvinyl acetal resin is within the above range, the generation of bubbles during use in a high-temperature environment is sufficiently suppressed, further improving the high-temperature heat resistance of the interlayer film. The lower limit of the hydroxyl group content is more preferably 20 mol% or more, even more preferably 25 mol% or more, and particularly preferably 30.9 mol% or more. The upper limit of the hydroxyl group content is more preferably 35% or less, even more preferably 33 mol% or less.

[0057] When a polyvinyl butyral resin is used as the polyvinyl acetal resin, from the same viewpoint, the lower limit of the hydroxyl group content is preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, and particularly preferably 30.9 mol% or more. The upper limit of the hydroxyl group content of the polyvinyl butyral resin is preferably 38 mol% or less, more preferably 35% or less, and even more preferably 33 mol% or less.

[0058] The amount of hydroxyl groups in a 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 K6728 (1977) "Testing Methods for Polyvinyl Butyral."

[0059] The degree of acetalization of the polyvinyl acetal resin is preferably 47 mol% or more, more preferably 55 mol% or more, and even more preferably 60 mol% or more. The degree of acetalization of the polyvinyl acetal resin is also preferably 85 mol% or less, more preferably 80 mol% or less, and even more preferably 75 mol% or less. Note that when the acetal group is a butyral group and the polyvinyl acetal resin is a polyvinyl butyral resin, the degree of acetalization refers to the degree of butyralization.

[0060] The degree of acetalization of a polyvinyl acetal resin is a molar fraction calculated by subtracting the amount of ethylene groups having hydroxyl groups and the amount of ethylene groups having acetyl groups 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, and the percentage of the molar fraction is expressed as a percentage. The degree of acetalization can be calculated, for example, from the results of measurements performed according to JIS K6728 (1977) "Testing Methods for Polyvinyl Butyral."

[0061] The acetylation degree of the polyvinyl acetal resin is preferably 30 mol% or less. This improves the moisture resistance of the interlayer film. The upper limit of the acetylation degree is more preferably 20 mol% or less, even more preferably 10 mol% or less, and particularly preferably 2 mol% or less. The lower limit of the acetylation degree is not particularly limited, but is preferably 0.01 mol% or more, more preferably 0.1 mol% or more.

[0062] The degree of acetylation of a polyvinyl acetal resin is the molar fraction calculated by dividing the amount of ethylene groups bonded to acetyl groups by the total amount of ethylene groups in the main chain, and is expressed as a percentage. The amount of ethylene groups bonded to acetyl groups can be measured, for example, in accordance with JIS K6728 (1977) "Testing Methods for Polyvinyl Butyral."

[0063] The polyvinyl acetal resin is preferably an unmodified polyvinyl acetal resin, but may also be a modified polyvinyl acetal resin. A modified polyvinyl acetal resin is one having a structure (modifying group) other than an acetal group, a hydroxyl group, and an acetyl group, and preferably has a modifying group on the side chain. Examples of the modifying group include those having a polyalkylene oxide structure on the side chain, and those having an alkyl group (e.g., having about 2 to 30 carbon atoms) other than an acetal group or an acetyl group on the side chain. The modification amount is not particularly limited, but is, for example, about 0.1 mol % to 10 mol %. The modification amount refers to the ratio of functional groups to all vinyl monomer units constituting the polyvinyl acetal resin.

[0064] When the first interlayer film and / or the second interlayer film contains a polyvinyl acetal resin, the interlayer film may further contain a thermoplastic resin other than a polyvinyl acetal resin. Examples of thermoplastic resins other than a polyvinyl acetal resin are as described above. However, it is preferable that the main component of the resin constituting the interlayer film is a polyvinyl acetal resin. Specifically, out of the total 100% by mass of resin components constituting the resin layers constituting each interlayer film (or each resin layer if each interlayer film has multiple resin layers), the polyvinyl acetal resin preferably accounts for 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and most preferably 100% by mass. That is, it is most preferable that the resin constituting each interlayer film is only a polyvinyl acetal resin.

[0065] The polyvinyl acetal resin is preferably produced by a production method including, for example, a mixing step of mixing polyvinyl alcohol with an aldehyde and a aging step of aging the mixture obtained in the mixing step. The acetalization of polyvinyl alcohol proceeds through the mixing step and the aging step, thereby producing the polyvinyl acetal resin. Note that, for example, when producing a thermoplastic resin such as a polyvinyl acetal resin, the intermolecular interaction can be adjusted by changing the reaction conditions and aging conditions.

[0066] In the mixing step, polyvinyl alcohol and aldehyde may be mixed according to a conventional method. In addition to polyvinyl alcohol and aldehyde, a catalyst such as an acid catalyst for promoting the acetalization reaction may be further added. For example, an aldehyde may be added to a mixture of polyvinyl alcohol and an acid catalyst at a low temperature of about 0 to 40°C. When two or more types of polyvinyl alcohol are used in combination (for example, when two or more types of polyvinyl alcohol having different molecular weights are used), the two or more types of polyvinyl alcohol may be mixed with the aldehyde.

[0067] In the aging step, for example, a catalyst such as an acid catalyst is added to the mixture (reaction mixture) obtained in the mixing step, followed by heating to an aging temperature and maintaining the mixture at the aging temperature for a certain period of time. After maintaining the reaction mixture at the aging temperature for a certain period of time, the reaction mixture may be appropriately cooled or neutralized, and then washed with water, dried, or the like, as necessary.

[0068] Examples of the acid catalyst that can be added in the mixing step and the aging step include inorganic acids such as hydrochloric acid, nitric acid, phosphoric acid, boric acid, sulfuric acid, etc. In the aging step, the concentration of the acid catalyst is preferably adjusted to, for example, about 0.5% by mass or more and 5% by mass or less, and more preferably adjusted to about 1% by mass or more and 2.5% by mass or less.

[0069] The aging temperature in the aging step may be relatively low, for example, preferably 35° C. to 60° C., more preferably 40° C. to 60° C., and even more preferably 40° C. to 57° C. The time for which the aging temperature is maintained (aging time) may be longer than a certain period, for example, preferably 75 minutes to 180 minutes, more preferably 90 minutes to 150 minutes, and even more preferably 100 minutes to 140 minutes. It is presumed that when the aging temperature and aging time are within the above ranges, hydroxyl groups in the polyvinyl acetal resin are more likely to be uniformly distributed throughout the molecule, which is thought to result in fewer low-molecular-weight components and a narrower molecular weight distribution.

[0070] (Plasticizer) When the first interlayer film and / or the second interlayer film contains a thermoplastic resin, the interlayer film preferably further contains a plasticizer. That is, the resin layer preferably further contains a plasticizer. When the interlayer film further contains a plasticizer in addition to a thermoplastic resin, the interlayer film becomes more flexible, thereby improving the adhesion of the interlayer film to various substrates and the penetration resistance of a laminated glass structure obtained using the interlayer film. Furthermore, adjusting the type and content of the plasticizer makes it easier to adjust the creep compliance per interlayer film layer within a predetermined range.

[0071] Preferred examples of the plasticizer include organic ester plasticizers, organic phosphate ester plasticizers such as organic phosphate ester plasticizers and organic phosphite ester plasticizers, organic ether plasticizers such as polyalkylene glycol plasticizers, and alcohol plasticizers. Among these, the plasticizer is preferably an organic ester plasticizer and / or an organic ether plasticizer.

[0072] Preferred examples of the organic ester plasticizer include monobasic organic acid esters and polybasic organic acid esters.

[0073] Examples of monobasic organic acid esters include esters of glycols and monobasic organic acids. The glycol is preferably a polyalkylene glycol or a monoalkylene glycol. The number of carbon atoms in each alkylene unit constituting the polyalkylene glycol and monoalkylene glycol is preferably 2 to 4, more preferably 2 or 3. Furthermore, in the polyalkylene glycol, the number of repeating alkylene units is preferably 2 to 10, more preferably 2 to 4. Specific examples of glycols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, and butylene glycol. Furthermore, 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, heptyl acid, n-octylic acid, 2-ethylhexyl acid, n-nonylic acid, and decylic acid.

[0074] Specific examples of the monobasic organic acid ester include triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethylene glycol di-n-octanoate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, tetraethylene glycol di-2-ethylhexanoate, diethylene glycol di-2-ethylbutyrate, diethylene glycol di-2-ethylhexanoate, dipropylene glycol di-2-ethylbutyrate, triethylene glycol Examples of such alkyl acrylates include glycerin di-2-ethylpentanoate, tetraethylene glycol di-2-ethylbutyrate, diethylene glycol dicaprylate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, triethylene glycol di-2-ethylbutyrate, ethylene glycol di-2-ethylbutyrate, 1,2-propylene glycol di-2-ethylbutyrate, 1,3-propylene glycol di-2-ethylbutyrate, 1,4-butylene glycol di-2-ethylbutyrate, and 1,2-butylene glycol di-2-ethylbutyrate.

[0075] Examples of polybasic organic acid esters include ester compounds of dibasic organic acids having 4 to 12 carbon atoms and alcohols having 4 to 10 carbon atoms. Examples of dibasic organic acids having 4 to 12 carbon atoms include adipic acid, sebacic acid, and azelaic acid. The alcohols having 4 to 10 carbon atoms may be linear, have a branched structure, or have a cyclic structure.

[0076] Specific examples of polybasic organic acid esters include dibutyl sebacate, dioctyl azelaate, dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, diisononyl adipate, heptylnonyl adipate, dibutyl carbitol adipate, and mixed adipates. The polybasic organic acid ester may also be an oil-modified alkyd sebacate. Examples of mixed adipates include adipates prepared from two or more alcohols selected from the group consisting of alkyl alcohols having 4 to 9 carbon atoms and cyclic alcohols having 4 to 9 carbon atoms.

[0077] The organic ester plasticizer is not limited to a complete ester of each of the above esters, but may also be a partial ester. For example, the organic ester plasticizer may be a partial ester of a glycol and a monobasic organic acid, or a partial ester of a dibasic organic acid and an alcohol. A specific example is triethylene glycol-mono-2-ethylhexanoate.

[0078] The organic ester plasticizer may also be a partial ester of a trivalent or higher alcohol, such as glycerin, with a monobasic organic acid. The number of carbon atoms in the monobasic organic acid is preferably 3 to 24, and more preferably 6 to 18. Specific examples include a mono- or diester of glycerin and stearic acid, and a mono- or diester of glycerin and 2-ethylhexyl acid.

[0079] Among the above-mentioned organic ester plasticizers, triethylene glycol-di-2-ethylhexanoate (3GO) is particularly preferably used.

[0080] Preferred examples of the organic phosphorus plasticizer include organic phosphate ester plasticizers, organic phosphite ester plasticizers, etc. Specific examples of the organic phosphorus plasticizer include phosphate esters such as tributoxyethyl phosphate, isodecylphenyl phosphate, and triisopropyl phosphate.

[0081] A preferred example of the organic ether-based plasticizer is a polyalkylene glycol-based plasticizer. Examples of the polyalkylene glycol-based plasticizer include polyoxyalkylene compounds having a polyoxyalkylene structure, specifically polyhydric alcohol compounds such as glycol; ester compounds of glycol and monobasic organic acid or polybasic organic acid; ether compounds of monohydric or polyhydric alcohol and polyoxyalkylene; etc. Here, examples of glycols include polyoxyalkylene glycols and derivatives thereof, and examples of polyoxyalkylenes include polyoxyethylene, polyoxypropylene, polyoxybutylene, random copolymers or block copolymers thereof, etc. As described above, the polyoxyalkylene compound may be a polyhydric alcohol compound, an ester compound, an ether compound, or other compounds.

[0082] Examples of polyoxyalkylene compounds include polyoxyalkylene and its derivatives. More specifically, examples include polyoxyalkylene glycols composed of polyoxyalkylene, and ether compounds of polyoxyalkylene and polyhydric alcohols. All of these may have hydroxyl groups at their terminals, or may be derivatives in which some or all of the hydrogen atoms of the terminal hydroxyl groups have been substituted with alkyl groups or acyl groups. The number of carbon atoms in the alkyl and acyl groups is not particularly limited, but may be about 1 to 8, preferably 1 to 4.

[0083] Examples of polyoxyalkylene glycols include polyoxyethylene polyoxypropylene glycols such as polyethylene glycol (polyoxyethylene glycol), polypropylene glycol (polyoxypropylene glycol), poly(ethylene oxide / propylene oxide) block copolymers and poly(ethylene oxide / propylene oxide) random copolymers, and polyoxybutylene glycols such as polytetramethylene glycol.

[0084] Examples of ether compounds of polyoxyalkylenes and polyhydric alcohols include ether compounds of polyoxyalkylenes with polyhydric alcohols such as glycerol, diglycerol, trimethylolpropane, erythritol, pentaerythritol, and bisphenol A, specifically polyoxyethylene glyceryl ether, polyoxypropylene glyceryl ether, polyoxyethylene diglyceryl ether, polyoxypropylene diglyceryl ether, polyoxyalkylene pentaerythritol ether, etc. Examples of derivatives in which some or all of the hydrogen atoms of terminal hydroxyl groups have been substituted with alkyl groups or acyl groups include the above-mentioned polyoxyalkylene glycols and derivatives in which some or all of the hydrogen atoms of terminal hydroxyl groups of ether compounds have been substituted with alkyl groups or acyl groups. Specific examples include polyoxyethylene glycol monomethyl ether, polyoxyethylene glycol dimethyl ether, polyoxypropylene glycol monomethyl ether, polyoxypropylene glycol dimethyl ether, polyoxyethylene polyoxypropylene glycol monomethyl ether, polyoxyethylene polyoxypropylene glycol dimethyl ether, polyoxyethylene glycol monobutyl ether, polyoxypropylene glycol monobutyl ether, and polyoxyethylene polyoxypropylene monobutyl ether.

[0085] Among the above-mentioned polyoxyalkylene compounds, compounds having a polyoxyethylene structure, a polyoxypropylene structure, or a polyoxyethylene polyoxypropylene structure are preferred, and among these, compounds having a polyoxypropylene structure or a polyoxyethylene polyoxypropylene structure are more preferred.Specifically, the polyoxyalkylene compound is preferably polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, or a derivative thereof in which some of the hydrogen atoms of the terminal hydroxyl groups are substituted with alkyl groups.

[0086] Preferred examples of the alcohol-based plasticizer include various polyhydric alcohols such as butanediol, hexanediol, trimethylolpropane, pentaerythritol, etc. Among these, trimethylolpropane is preferred.

[0087] Among the above-mentioned compounds, the plasticizer is preferably at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate (3GO), polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives thereof in which some of the hydrogen atoms of the terminal hydroxyl groups have been substituted with alkyl groups, and 3GO is more preferred.

[0088] When the resin layer further contains a plasticizer, the content of the plasticizer (total amount when two or more types are contained) is preferably, for example, 10 parts by mass or more per 100 parts by mass of the thermoplastic resin contained in the resin layer (one layer). This makes the interlayer film moderately flexible, further improving the adhesion of the interlayer film to various substrates and the penetration resistance of the laminated glass structure. The content of the plasticizer per 100 parts by mass of the thermoplastic resin is more preferably 15 parts by mass or more, even more preferably 30 parts by mass or more, and particularly preferably 35 parts by mass or more. The content of the plasticizer is also preferably 100 parts by mass or less per 100 parts by mass of the thermoplastic resin. This sufficiently prevents the plasticizer from separating from the interlayer film. The content of the plasticizer per 100 parts by mass of the thermoplastic resin is more preferably 70 parts by mass or less, even more preferably 60 parts by mass or less, particularly preferably 50 parts by mass or less, and most preferably 45 parts by mass or less.

[0089] (Other Additives) The first interlayer film and / or the second interlayer film may also contain, as appropriate, known additives that can be used in combination with thermoplastic resins. That is, for example, the resin layer may contain known additives. Examples of additives other than plasticizers include ultraviolet absorbers, heat shielding agents, colorants, infrared absorbers, antioxidants, light stabilizers, adhesion modifiers, fluorescent whitening agents, and crystal nucleating agents. Each of the additives may be used alone, or two or more may be used in combination.

[0090] (Ultraviolet Absorber) When the interlayer film contains an ultraviolet absorber, deterioration of the functional layer due to ultraviolet rays is sufficiently suppressed. For example, it is preferable that the resin layer of at least one of the first interlayer film and the second interlayer film further contains an ultraviolet absorber.

[0091] The ultraviolet absorber is not particularly limited, and examples thereof include compounds having a malonic acid ester structure, compounds having an oxalic acid anilide structure, compounds having a benzotriazole structure, compounds having a benzophenone structure, compounds having a triazine structure, compounds having a benzoate structure, compounds having a hindered amine structure, and compounds having an indole structure. Among these, the ultraviolet absorber is preferably a compound having a benzotriazole structure from the viewpoint of excellent compatibility with thermoplastic resins and weather resistance. Examples of compounds having a benzotriazole structure include commercially available Tinuvin 234, Tinuvin 326, Tinuvin 327, Tinuvin 640, and Tinuvin 928 (manufactured by BASF Corporation); Eversorb 88 and Eversorb 109 (manufactured by Everlight Chemical Co.).

[0092] When the resin layer contains an ultraviolet absorber, the content of the ultraviolet absorber (the total amount when two or more types are contained) is, for example, preferably 0.1% by mass or more, more preferably 0.2% by mass or more, based on 100% by mass of the total amount of the materials constituting the resin layer (one layer). The content of the ultraviolet absorber is also preferably 5% by mass or less, more preferably 3% by mass or less, based on 100% by mass of the total amount of the materials constituting the resin layer (one layer).

[0093] (Heat-shielding agent) When the interlayer film contains a heat-shielding agent, deterioration of the functional layer due to heat is sufficiently suppressed. For example, it is preferable that the resin layer of at least one of the first interlayer film and the second interlayer film further contains a heat-shielding agent. Furthermore, at least one of the first interlayer film and the second interlayer film may have, separately from or in addition to the resin layer, a layer made of a heat-shielding agent (for example, a layer made of heat-shielding particles described below) or a layer containing a heat-shielding agent.

[0094] The heat-shielding agent is a material capable of absorbing infrared rays (also called heat rays) of 780 nm or more. Specifically, the heat-shielding agent is preferably heat-shielding particles. The heat-shielding particles are made of an inorganic material, and specific examples thereof include metal oxide particles and particles other than metal oxide particles, such as lanthanum hexaboride (LaB6) particles. Examples of the 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); sodium-doped tungsten oxide particles and cesium-doped tungsten oxide particles (CWO particles); tungsten oxide particles such as thallium-doped tungsten oxide particles and rubidium-doped tungsten oxide particles; and the like. Heat-shielding particles other than these may also be used. Among these, from the viewpoint of high heat ray shielding function, the heat shielding agent is preferably metal oxide particles, more preferably at least one selected from the group consisting of ATO particles, GZO particles, ITO particles and CWO particles, and more preferably ITO particles and / or CWO particles.

[0095] The lower limit of the average particle size of the heat-shielding particles is preferably 10 nm or more, and more preferably 20 nm or more. When the average particle size is within this range, the heat ray shielding ability of the heat-shielding particles is further improved. Furthermore, the upper limit of the average particle size of the heat-shielding particles is preferably 100 nm or less, more preferably 80 nm or less, and even more preferably 50 nm or less. When the average particle size is within this range, the heat-shielding particles become less able to shield visible light. Note that the "average particle size" referred to here refers to the volume average particle size. The average particle size can be measured using a particle size distribution analyzer ("UPA-EX150" manufactured by Nikkiso Co., Ltd.) or the like.

[0096] The heat-shielding agent may also be an organic material or an organic-inorganic composite material (also referred to as a shielding compound) capable of absorbing infrared rays, which are also near-infrared absorbers. A near-infrared absorber has an absorption maximum in the near-infrared region, and this absorption maximum exhibits the greatest absorption among the absorption maxima present in the wavelength region of 380 nm to 2500 nm. Specifically, the near-infrared absorber has a maximum absorption in a wavelength region of 720 nm or more, preferably in a wavelength region of 750 nm to 2000 nm.

[0097] The heat-shielding compound is preferably at least one selected from the group consisting of a phthalocyanine compound, a naphthalocyanine compound, and an anthracyanine compound. The phthalocyanine compound is phthalocyanine or a phthalocyanine derivative having a phthalocyanine skeleton, and preferably contains a metal atom. The naphthalocyanine compound is naphthalocyanine or a naphthalocyanine derivative having a naphthalocyanine skeleton, and preferably contains a metal atom. The anthracyanine compound is an anthracyanine or an anthracyanine derivative having an anthracyanine skeleton, and preferably contains a metal atom. In the phthalocyanine compound, the naphthalocyanine compound, and the anthracyanine compound, the metal atom is the central metal of the naphthalocyanine skeleton, the naphthalocyanine skeleton, and the anthracyanine skeleton, respectively.

[0098] Among the above, the heat-shielding compound is preferably at least one selected from the group consisting of a phthalocyanine compound and a naphthalocyanine compound, and more preferably a phthalocyanine compound. Furthermore, the metal atom is preferably a vanadium atom. Therefore, the heat-shielding compound is particularly preferably a phthalocyanine compound containing a vanadium atom. The vanadium atom generally exists in a state where an oxygen atom is bonded to it (V=O). Furthermore, it is also preferable to use tungsten oxide particles and a phthalocyanine compound in combination as the heat-shielding agent, and it is more preferable to use CWO particles and a phthalocyanine compound in combination.

[0099] When the resin layer contains a heat-shielding agent, the content of the heat-shielding agent (the total amount when two or more types are contained) is, for example, preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.15% by mass or more, relative to 100% by mass of the total amount of materials constituting the resin layer (one layer). The content of the heat-shielding agent is also preferably 1.5% by mass or less, more preferably 1.2% by mass or less, and even more preferably 0.9% by mass or less, relative to 100% by mass of the total amount of materials constituting the resin layer (one layer).

[0100] (Colorant) When the interlayer film contains a colorant, the laminated glass structure is well colored to a desired color tone, improving the design. For example, it is preferable that the resin layer of at least one of the first interlayer film and the second interlayer film further contains a colorant. Examples of the colorant include pigments and dyes, and both pigments and dyes may be used in combination. Note that there are also colorants that are classified as both pigments and dyes.

[0101] Examples of pigments include perylene compounds, threne compounds, quinacridone compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, perinone compounds, phthalocyanine compounds, indanthrene compounds, indigo compounds, isoindolinone compounds, nickel complex compounds, methine compounds, azomethine compounds, dioxazines, azo compounds, and carbon black.

[0102] Examples of dyes include perylene compounds, threne compounds, quinacridone compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, perinone compounds, phthalocyanine compounds, indanthrene compounds, indigo compounds, isoindolinone compounds, nickel complex compounds, methine compounds, azomethine compounds, dioxazines, and azo compounds.

[0103] When the resin layer contains a colorant, the content of the colorant (the total amount when two or more types are contained) is, for example, preferably 0.00001% by mass or more, more preferably 0.0001% by mass or more, and even more preferably 0.001% by mass or more, based on 100% by mass of the total amount of materials constituting the resin layer (one layer). The content of the dye is also preferably 0.15% by mass or less, more preferably 0.12% by mass or less, based on 100% by mass of the total amount of materials constituting the resin layer (one layer).

[0104] When the interlayer film contains a pigment as a colorant, the pigment content (total amount when two or more types are contained) is, for example, preferably 0.0001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.02% by mass or more, based on 100% by mass of the total amount of materials constituting the resin layer (one layer). The pigment content is also preferably 0.15% by mass or less, more preferably 0.12% by mass or less, based on 100% by mass of the total amount of materials constituting the resin layer. The interlayer film may contain only one type of pigment, two or more types, three or more types, or 10 or fewer types, or five or fewer types.

[0105] When the interlayer film contains a dye as a colorant, the content of the dye (the total amount when two or more types are contained) is, for example, preferably 0.00001% by mass or more, more preferably 0.0001% by mass or more, and even more preferably 0.001% by mass or more, based on 100% by mass of the total amount of materials constituting the resin layer (one layer). The content of the dye is also preferably less than 0.015% by mass, more preferably 0.01% by mass or less, based on 100% by mass of the total amount of materials constituting one resin layer. The number of dyes that can be contained in the interlayer film may be one, two or more, three or more, or 10 or fewer, or 5 or fewer.

[0106] (Thickness) The thickness of the first interlayer film in the laminated glass structure is not particularly limited, but the layer thickness of the interlayer film (meaning the total thickness in the case of a multilayer film) is preferably 100 μm or more, more preferably 200 μm or more, and even more preferably 300 μm or more. The thickness of the second interlayer film is also not particularly limited, but the layer thickness of the interlayer film (meaning the total thickness in the case of a multilayer film) is preferably 100 μm or more, more preferably 200 μm or more, and even more preferably 300 μm or more. When each interlayer film has a certain thickness or more, residual air and bubbles are more sufficiently suppressed when the glass plate and the glass plate are pressure-bonded together.

[0107] The film thickness (total thickness) of the first interlayer film is preferably 2000 μm or less, more preferably 1300 μm or less, even more preferably 1000 μm or less, and particularly preferably 800 μm or less. The film thickness (total thickness) of the second interlayer film is also preferably 2000 μm or less, more preferably 1300 μm or less, even more preferably 1000 μm or less, and particularly preferably 800 μm or less. By ensuring that the thickness of each interlayer film is a certain value or less, the laminated glass structure is prevented from becoming thicker than necessary.

[0108] In the first interlayer film, it is preferable that the thickness of the layer that satisfies the above creep compliance value accounts for a certain percentage or more of the total thickness of the first interlayer film. This more sufficiently suppresses residual air and bubbles when the first interlayer film is pressed against the glass plate. For example, when the first interlayer film is a multilayer film, when the film thickness (total thickness) of the first interlayer film is taken as 100%, the thickness of the layer that satisfies the above creep compliance value is preferably 10 to 100%, more preferably 30 to 100%, even more preferably 50 to 100%, particularly preferably 75 to 100%, and most preferably 100%.

[0109] In the second interlayer film, it is also preferable that the thickness of the layer that satisfies the above creep compliance value accounts for a certain percentage or more of the total thickness of the second interlayer film. This more sufficiently suppresses residual air and bubbles when the second interlayer film is pressed against the glass plate. For example, when the second interlayer film is a multilayer film, the thickness of the layer that satisfies the above creep compliance value is preferably 10 to 100%, more preferably 30 to 100%, even more preferably 50 to 100%, particularly preferably 75 to 100%, and most preferably 100%, of the total thickness (total thickness) of the second interlayer film taken as 100%.

[0110] Furthermore, when the total thickness of the laminated glass structure is taken as 100%, the thickness of the layer that satisfies the above creep compliance value (when two or more layers are included, the total thickness of the layers) is preferably 10 to 50%, more preferably 20 to 40%.

[0111] (Uneven Shape) For at least one of the first interlayer film and the second interlayer film, it is preferable that at least one surface of the interlayer film has an uneven shape. More specifically, it is preferable that at least one surface of the interlayer film has a plurality of recesses and a plurality of protrusions, and it is more preferable that both surfaces of the interlayer film have a plurality of recesses and a plurality of protrusions. Furthermore, when the first interlayer film and / or the second interlayer film is a multilayer film, it is preferable that one or both surfaces of the outermost layer of the interlayer film have an uneven shape.

[0112] The recesses preferably have a groove shape with a continuous bottom. A groove shape with a continuous bottom is also referred to as a "ruled line" shape. Therefore, for at least one of the first interlayer film and the second interlayer film, it is preferable that at least one surface of the interlayer film has a ruled line-shaped recess, and it is more preferable that both surfaces of the interlayer film have ruled line-shaped recesses. For example, when attempting to pre-bond a glass plate and an interlayer film using a rubber bag to obtain a laminated glass structure, the edges are temporarily bonded first, which can make it difficult for air to escape from near the center. However, if the surface of the interlayer film has ruled line-shaped recesses, air can also easily escape from near the center, improving adhesion during pre-bonding.

[0113] For at least one of the first interlayer film and the second interlayer film, it is preferable that at least one surface of the interlayer film has a plurality of ruled recesses. In this case, it is preferable that the ruled recesses are arranged in parallel, and it is more preferable that adjacent ruled recesses are arranged in a regular, parallel arrangement. The ease with which air escapes (also referred to as degassing ability) when a laminate film in which an interlayer film is laminated between a pair of glass plates is pressure-bonded is closely related to the interconnectedness and smoothness of the bottoms of the recesses on the interlayer film surface. By forming the irregular shape of at least one surface of the interlayer film in a shape in which adjacent ruled recesses are arranged in a regular, parallel arrangement, the interconnectedness of the bottoms is improved, and degassing ability is further improved.

[0114] The spacing Sm between adjacent ruled recesses is preferably 100 μm or more and preferably 500 μm or less. When the spacing Sm between the ruled recesses is within this range, even better degassing properties are exhibited. The lower limit of the spacing Sm between the ruled recesses is more preferably 160 μm or more, and the upper limit is more preferably 350 μm or less, and even more preferably 250 μm or less. The spacing Sm between the ruled recesses is determined by observing the first and second surfaces of the interlayer film (observation area 20 mm × 20 mm) using an optical microscope (manufactured by SONIC Corporation, "BS-D8000III"), measuring the spacing between adjacent recesses, and then calculating the average value of the shortest distance between the bottoms of adjacent recesses.

[0115] In the regularly arranged parallel ruled recesses, adjacent ruled recesses are preferably parallel and equally spaced, but the intervals between all adjacent ruled recesses do not have to be equal. The ruled recesses do not need to have a continuous groove shape across the entire bottom, and may have a dividing wall in part of the bottom. Furthermore, as long as adjacent recesses are parallel and regularly arranged, the groove shape at the bottom does not have to be linear. For example, the groove shape at the bottom may be wavy or zigzag.

[0116] In an interlayer film having an uneven surface on at least one side, the surface roughness (RzJIS94) of the uneven surface is preferably 10 to 80 μm. When the surface roughness is within this range, the interlayer film can exhibit excellent degassing properties. The surface roughness is more preferably 20 to 65 μm, and even more preferably 20 to 50 μm.

[0117] Surface roughness (RzJIS94) can be measured in accordance with JIS B0601 (1994). Here, when the depressions of the surface irregularity are in the form of ruled lines, the measurement is performed in a direction perpendicular to the direction in which the depressions in the ruled line direction continue. For example, a measuring instrument such as the "Surfcorder SE300" manufactured by Kosaka Laboratory Co., Ltd. is used. The cutoff value during measurement is 2.5 mm, the reference length is 2.5 mm, the measurement length is 12.5 mm, the preliminary length is 2.5 mm, the palpation needle feed rate is 0.5 mm / sec, and the palpation needle shape has a tip radius of 2 μm and a tip angle of 60°. The measurement is performed in an environment of 23°C and 30% RH. The interlayer film to be measured is left to stand in the measurement environment for at least 3 hours before measurement.

[0118] Furthermore, in an interlayer film having an uneven surface on at least one side, the surface roughness (Rc) of the uneven surface is preferably 10 to 40 μm. When the surface roughness is within this range, the interlayer film can exhibit excellent degassing properties. The surface roughness (Rc) is more preferably 15 to 35 μm, and even more preferably 19 to 30 μm. The surface roughness (Rc) can be measured in accordance with JIS B0601 (2013).

[0119] Each interlayer film can be produced by, for example, extrusion molding or press molding, but extrusion molding is preferred. Methods for forming a textured surface on the interlayer film include, for example, an embossing roll method, a calendar roll method, a profile extrusion method, and a melt fracture method. Among these, the embossing roll method is preferably used.

[0120] The first interlayer film provided in the laminated glass structure of the present disclosure (i.e., an interlayer film having the creep compliance per interlayer film within a predetermined range) itself was discovered by the present inventors. That is, a film composed of the first interlayer film provided in the laminated glass structure is also included in the present disclosure. A film composed of the first interlayer film for the laminated glass structure is also included in the present disclosure. The use of a film composed of the first interlayer film in the laminated glass structure is also included in the present disclosure.

[0121] [Functional Layer] The laminated glass structure has a functional layer located between the first interlayer film and the second interlayer film. The functional layer is not particularly limited as long as it has a predetermined function, but is preferably a functional film. The functional film is preferably, for example, a light control film, a display element film, a hologram film, or an optical film, and examples of optical films include a polarizing film, a retardation film, an anti-reflection film, and a holographic film. The functional layer may also be a solar cell element, as described below.

[0122] The functional film is more preferably a film including electronic components such as a light control film or a display element film, and even more preferably a light control film or a display element film. That is, the functional layer is preferably at least one selected from the group consisting of a light control film and a display element film.

[0123] Typically, films equipped with electronic components tend to deteriorate or lose their functionality when subjected to autoclaving under high-temperature and high-pressure conditions. However, the laminated glass structure of the present disclosure can be suitably produced even by autoclaving at low temperatures, and therefore the functional layer can be incorporated into the laminated glass structure without being deactivated. Therefore, the laminated glass structure of the present disclosure can effectively exhibit the functionality inherent to the functional layer. Furthermore, films equipped with electronic components are prone to complex steps (thickness differences) due to the provision of electronic wiring, shielding printed portions, etc., which makes it easy for air to remain or bubbles to form between the interlayer film and the glass plate or functional layer during pressure bonding. However, in the present disclosure, such air remaining or bubbles are sufficiently suppressed even when pressure bonding is performed at low temperatures, and the resulting laminated glass structure has excellent transparency and a good appearance. Furthermore, laminated glass structures (e.g., window glass) incorporating a light control film or a display element film have high added value, such as excellent design.

[0124] The light control film is a film-like component equipped with a light control element. Specifically, the light control film preferably comprises two resin films and a light control layer disposed between the two resin films. In a light control film having such a configuration, the surfaces in contact with the first interlayer film and the second interlayer film are made of resin material, which can improve adhesion to these interlayer films.

[0125] The resin film used in the light-controlling film is not particularly limited, but examples thereof include polyester resin films such as polyethylene terephthalate (PET) film and polyethylene naphthalate (PEN) film; (meth)acrylic resin film; triacetyl cellulose (TAC) film; polyethersulfone (PES) resin film; polyimide resin film; etc. Among these, from the viewpoint of handleability, etc., the resin film is preferably a polyester resin film, and PET film is more preferable. Note that each of the two resin films may be provided with a conductive layer constituting an electrode on the surface facing the light-controlling layer.

[0126] The light-controlling layer changes its visible light transmittance by switching between application and non-application of a voltage between the conductive layers provided on each of the two resin films. Preferred examples of the light-controlling layer include liquid crystal layers such as polymer-dispersed liquid crystal (PDLC) and guest-host liquid crystal (GHLC); suspended particle device (SPD) layers containing a resin matrix and a light-controlling suspension dispersed therein; electrochromic material layers; and electrophoretic layers containing electrophoretic particles and a dispersant for dispersing the electrophoretic particles. Therefore, the light-controlling film preferably includes at least one material selected from the group consisting of PDLC, GHLC, SPD, electrochromic devices, and electrophoretic film devices. That is, the functional layer preferably includes at least one material selected from the group consisting of PDLC films, GHLC films, SPD films, electrochromic films, and electrophoretic film devices.

[0127] The display element film is a film-like member including a display element. Specifically, the display element film preferably includes a resin film and a display element mounted on the resin film, and more preferably includes two resin films and a display element disposed between the two resin films. A display element film configured in this manner can have improved adhesion to the first interlayer film and the second interlayer film. Note that the resin film used in the display element film can be appropriately selected from the resin films described above with respect to the light control film. Furthermore, the resin film constituting the display element film may be provided with a conductive layer constituting an electrode on the surface facing the display element.

[0128] The film having electronic components is not limited to a light control film or a display element film, but may be other functional films. In other functional films, the electronic components may be mounted on the resin film in the same manner as in the light control film and the display element film, but a preferred embodiment is one in which the electronic components are disposed between a pair of resin films.

[0129] The functional layer may also be a solar cell element. By using a solar cell element in the functional layer, the laminated glass structure of the present disclosure can provide laminated glass for building-integrated photovoltaics (BIPV). The solar cell element is not particularly limited as long as it is a solar cell element used in BIPV. Examples include crystalline or thin-film silicon solar cell elements; compound semiconductor solar cell elements such as CIS, CIGS, CdTe, and GaAs; and organic solar cell elements such as dye-sensitized, organic thin film, and perovskite.

[0130] [Laminate Film] The laminated glass structure of the present disclosure, which comprises a first interlayer film, a functional layer, and a second interlayer film, is useful for a variety of applications in addition to applications for providing laminated glass structures. Such laminated films comprising a first interlayer film, a functional layer, and a second interlayer film are included in the present disclosure. The present disclosure also includes a laminated film comprising a first interlayer film, a functional layer, and a second interlayer film for the above-mentioned laminated glass structure. The present disclosure also includes the use of a laminated film comprising a first interlayer film, a functional layer, and a second interlayer film in the above-mentioned laminated glass structure.

[0131] The laminated film can be produced by, for example, thermocompression bonding a first interlayer film, a functional layer, and a second interlayer film. When the laminated film is incorporated into a laminated glass structure, the thermocompression bonding may be performed by first thermocompression bonding the first interlayer film, the functional layer, and the second interlayer film to form a laminated film, and then pressing the laminated film to a glass plate to form the laminated glass structure. Alternatively, the first interlayer film, the functional layer, and the second interlayer film before pressing may be disposed between two glass plates, and when the glass plate and the laminated film are pressed together, the first interlayer film, the functional layer, and the second interlayer film may also be pressed together.

[0132] Here, it is preferable to use a functional layer having a smaller planar area than each interlayer film, and to arrange the first interlayer film, functional layer, and second interlayer film so that each interlayer film is present around the functional layer in a plan view (see, for example, Figures 2 and 3 described below). In this case, it is not necessary to arrange a gap filler around the periphery of the functional layer. The laminated glass structure of the present disclosure can be suitably produced without using a gap filler.

[0133] [Various Physical Properties] In the laminated glass structure of the present disclosure, the first glass plate, the first interlayer film, the functional layer, the second interlayer film, and the second glass plate preferably have curved shapes such that they all have convex portions in the same direction. For example, taking the laminated glass structure shown in FIG. 1 as an example, this shape refers to a shape in which the glass plates G1 and G2, the interlayer films F1 and F2, and the functional layer all have convex portions in the same direction (e.g., downward in FIG. 1). Because the laminated glass structure has the first interlayer film with low rigidity and high flexibility as described above, various shapes can be realized. Furthermore, it is preferable that the radius of curvature of the inner surface (i.e., concave surface) of each glass plate, each interlayer film, and each functional layer is 1,000 to 20,000 mm.

[0134] It is also preferable that the thickness of the edge of the laminated glass structure is 99% or less of the thickness of the center of the laminated glass structure, where the thickness of the center is 100%. The center of the laminated glass structure means the centroid (the center in a plan view) of the laminated glass structure. This sufficiently suppresses moisture penetration from the edge, making the laminated glass structure excellent in moisture resistance and allowing the functions derived from the functional layer to be more effectively exhibited. Note that when the glass plates, interlayer film, and functional layer are arranged so that the centroids of each component overlap, the center of the laminated glass structure corresponds to the center (b) of the region having the above-mentioned functional layer.

[0135] It is preferable that the visible light transmittance at a wavelength of 390 nm of the region (a) of the laminated glass structure that does not have a functional layer is lower than the visible light transmittance at a wavelength of 390 nm of the central portion (b) of the region of the laminated glass structure that has a functional layer. This further improves the appearance of the laminated glass structure. A laminated glass structure of this type can be easily obtained, for example, by manufacturing it without using a gap filler. The visible light transmittance can be measured in accordance with JIS R3106 (1998).

[0136] Here, the region (a) of the laminated glass structure that does not have a functional layer refers to a portion (e.g., an end portion of the laminated glass structure) where no functional layer is disposed when the laminated glass structure, each interlayer film, and a functional layer having a smaller planar size than these are arranged so that their centroids overlap in a plan view, as described below (see Figures 2 and 3). For example, the thickness and transmittance of the region (a) refer to the thickness and transmittance of a portion 30 to 70% away from the intersection point Y1 when the horizontal length between the intersection points Y1 and Y2 is taken as 100% in a plan view of the laminated glass structure. The intersection point Y1 is the point where a center line passing through the center portion (b) of the region of the laminated glass structure that has a functional layer intersects with the edge of the region that has a functional layer. The intersection point Y2 is the point where the center line intersects with the edge of the laminated glass structure.

[0137] The central portion (b) of the region having the functional layer in the laminated glass structure is the central portion of the region where the functional layer is arranged (i.e., the centroid of the functional layer) when the laminated glass structure including the functional layer is viewed in plan.

[0138] In this specification, the thicknesses are measured using, for example, a multilayer film thickness measuring device "OptiGauge" manufactured by Lumetrics, Inc. In addition, when it is difficult to measure using an optical method, such as when it is difficult to pass electricity through the light control film, the laminated glass structure may be appropriately cut out and the thickness may be measured using a vernier caliper or the like.

[0139] The laminated glass structure preferably has a maximum ultraviolet transmittance of 30% or less in the wavelength range of 370 to 400 nm. More precisely, the "maximum ultraviolet transmittance in the wavelength range of 370 to 400 nm" refers to the highest transmittance measured at each wavelength in the range of 370 to 400 nm. When the ultraviolet transmittance is within the above range, deterioration of the functional layer due to ultraviolet rays is more sufficiently suppressed. The maximum ultraviolet transmittance is more preferably 20% or less. The ultraviolet transmittance can be measured in accordance with JIS R3106 (1998).

[0140] [Method for Manufacturing Laminated Glass Assembly] The laminated glass assembly of the present disclosure is preferably manufactured by a method in which the laminated film is disposed between a pair of glass sheets and pressure-bonded to obtain a laminated glass assembly. As described above, the use of the first interlayer film sufficiently prevents peeling at the layer interface, residual air, and bubbles from forming, even without the use of a gap filler. Therefore, in the manufacturing method, it is preferable to pressure-bond the glass sheets and the laminated film without disposing a gap filler on the periphery of the functional layer. In this case, the manufacturing method omits the step of disposing a gap filler, thereby simplifying the manufacturing process and sufficiently suppressing, for example, a decrease in yield due to shrinkage of the gap filler. Furthermore, the cost of materials used in the gap filler is eliminated, making it extremely useful industrially. Furthermore, the absence of a gap filler can reduce the film thickness at the edges of the laminated glass assembly, sufficiently suppressing moisture penetration into the laminated glass assembly and effectively demonstrating the effects of the functional layer.

[0141] In the above-described manufacturing method, first, a first glass plate, a second glass plate, and the laminate film or each component constituting the laminate film (each interlayer film and functional layer) to be disposed between these glass plates are prepared.

[0142] As described above, a functional member may be attached to at least one of the first glass plate and the second glass plate. However, it is preferable that the functional member is attached to the glass plate before it is integrated into the laminated glass structure. Therefore, a glass plate having a functional member attached thereto may be prepared as at least one of the first glass plate and the second glass plate used in the above-mentioned manufacturing method. For example, as described above, when the glass plate constitutes a substrate of a display device, a display device may be prepared as at least one of the first glass plate and the second glass plate.

[0143] In the above-mentioned manufacturing method, it is preferable to next place the laminate film between a first glass plate and a second glass plate and bond them together to form an integrated laminated glass structure. It is also preferable to place each component constituting the laminate film (i.e., each interlayer film and functional layer) between the first glass plate and the second glass plate and bond them together to form an integrated laminated glass structure incorporating the laminate film. Here, each component constituting the laminate film may be arranged according to the layer structure of the resulting laminated glass structure. For example, the first interlayer film, the functional layer, and the second interlayer film may be arranged in this order between the first glass plate and the second glass plate.

[0144] The lamination (also referred to as lamination or main lamination) may be performed in a two-stage process of preliminary lamination followed by main lamination, or in one stage, but two stages are preferred. The preliminary lamination may be performed using a vacuum bag, a ring bag, a nipper roll, or a press other than these. The main lamination is preferably performed in an autoclave, but may also be performed using other presses. When laminating in one stage, lamination is preferably performed using a vacuum bag or a ring bag, but may also be performed using other presses.

[0145] In the above-mentioned manufacturing method, the lamination may be carried out at a low temperature depending on the heat resistance of the functional layer. As described above, the interlayer film has excellent fluidity, so even if a laminated glass structure is produced by lamination at a low temperature or low pressure, the resulting laminated glass structure can exhibit high safety. Note that, by carrying out the lamination at a low temperature or low pressure, deterioration or deactivation of the functional layer is sufficiently prevented. Furthermore, even if a functional member or the like is attached to the glass plate, deterioration or deactivation of the member is sufficiently prevented.

[0146] From the viewpoint of more reliably preventing deterioration or deactivation of the functional layer, etc., the temperature during lamination is preferably 110° C. or lower, more preferably 100° C. or lower. Furthermore, from the viewpoint of more reliably preventing the generation of residual air and foaming, the temperature during lamination is preferably 60° C. or higher, more preferably 70° C. or higher.

[0147] Similarly, from the viewpoint of more reliably preventing deterioration or deactivation of the functional layer, etc., the pressure when performing the lamination is preferably 1.2 MPa or less, more preferably 0.8 MPa or less. The lower limit of the pressure when performing the lamination is not particularly limited, but for example, when the lamination is performed under pressure such as in an autoclave, the pressure is preferably 0.05 MPa or more, more preferably 0.1 MPa or more.

[0148] The time for lamination at the above temperature and / or pressure is not particularly limited, but is preferably 1 to 120 minutes, more preferably 5 to 60 minutes.

[0149] In the above-mentioned manufacturing method, it is preferable to carry out preliminary adhesion (also referred to as preliminary lamination or temporary pressure bonding) before the lamination, as described above, which can sufficiently suppress the decrease in transmittance and adhesive strength that may occur during the autoclave process under low-temperature conditions.

[0150] Depending on the type of functional layer, etc., the preliminary bonding may be performed under low temperature conditions, or under low temperature and low pressure conditions, in order to further prevent deterioration or deactivation. In such cases, for example, the temperature during preliminary bonding is preferably 110°C or lower, more preferably 100°C or lower. Furthermore, in order to further prevent the generation of residual air and foaming, the temperature during preliminary bonding is preferably 60°C or higher, more preferably 70°C or higher. The pressure during preliminary bonding is preferably 0.6 MPa or lower. Furthermore, when preliminary bonding is performed under negative pressure, such as when using a vacuum bag, the pressure during preliminary bonding is preferably 0.3 MPa or lower, more preferably 0.095 MPa or lower, and even more preferably 0.09 MPa or lower. When preliminary bonding is performed under pressure, the pressure is preferably 0.01 MPa or higher, more preferably 0.05 MPa or higher.

[0151] The time for which preliminary bonding is carried out at the above temperature and / or pressure is not particularly limited, but is preferably 0 to 60 minutes, and more preferably 0 to 30 minutes.

[0152] [Applications] The laminated glass structure of the present disclosure can be used in a wide variety of applications. For example, the laminated glass structure of the present disclosure is used as window glass for vehicles such as automobiles and trains, various vehicles such as ships and airplanes, various buildings such as buildings, condominiums, detached houses, halls, and gymnasiums, machine tools for cutting and polishing, construction machinery such as shovels and cranes, and partitions inside various vehicles and buildings. In particular, the laminated glass structure is preferably used for vehicle applications such as automobiles and trains, or for architectural applications. As described above, both laminated glass for vehicles and laminated glass for buildings composed of the laminated glass structure of the present disclosure have been discovered by the present inventors. The laminated glass structure is particularly preferably used as window glass for vehicles or BIPV, and is particularly preferably used as window glass for vehicles. The window glass for vehicles is preferably the windshield, side glass, rear glass, or roof glass of an automobile or train.

[0153] The laminated glass structure of the present disclosure is also preferably used for various display applications. For example, window glass, partitions, etc. using the laminated glass structure may be used as displays. The laminated glass structure of the present disclosure can also be used as cover glass, etc. for various displays. For example, the laminated glass structure may be applied to in-vehicle displays, etc.

[0154] 2. Laminated Glass Constructs and Laminated Films of the Present Disclosures 2-1 to 2-10 As described above, the laminated glass construct of the present disclosure 2-1 comprises a first glass plate, a first interlayer film, a light control film, a second interlayer film, and a second glass plate, in this order, and the first glass plate, the first interlayer film, the light control film, the second interlayer film, and the second glass plate are curved so that they have convex portions in the same direction. The absolute value |a-b| of the difference between the thickness (a) of the region of the laminated glass construct that does not have the light control film and the thickness (b) of the center of the region that has the light control film, divided by the thickness (c) of the light control film, (|a-b| / c), is 0.1 to 0.5. Such a laminated glass construct can effectively exhibit the functions derived from the light control film without using a gap filler, has a good appearance, and is highly safe.

[0155] The laminated glass structures and laminated films of the present disclosures 2-1 to 2-10 will be described below. Note that the following mainly describes the characteristics unique to the laminated glass structures and the like of the present disclosures 2-1 to 2-10, and explanations of matters overlapping with those described in "1." above will be omitted.

[0156] [Layer structure] For details of the layer structure of the laminated glass structure and preferred embodiments thereof, the explanation given in the section "1." [Layer structure] above is to be cited (see also Fig. 1). The term "functional layer" shall be read as "light control film".

[0157] [Glass Plates] The laminated glass structure has a first glass plate and a second glass plate. Details and preferred embodiments of each glass plate are described in the section "1." [Glass Plates] above.

[0158] [Interlayer film] The laminated glass structure has at least a pair of interlayer films arranged to sandwich the light control film. One of the pair of interlayer films is referred to as a first interlayer film, and the other is referred to as a second interlayer film. The first interlayer film and the second interlayer film may have the same configuration as each other, or may be different.

[0159] The first interlayer film and the second interlayer film are preferably the same as the first interlayer film and the second interlayer film, respectively, of the laminated glass structure of the present disclosure 1-1. Therefore, the details and preferred embodiments of each interlayer film (e.g., layer structure, creep compliance value, Tg, types and amounts of contained components, thickness, uneven shape, manufacturing method, etc.) are as described in the above section "1." [Interlayer film]. The term "functional layer" should be read as "light control film."

[0160] The first interlayer film included in the laminated glass structure of the present disclosure (i.e., for example, an interlayer film having the creep compliance per interlayer film within a predetermined range) itself was discovered by the present inventors. That is, a film composed of the first interlayer film included in the laminated glass structure is also included in the present disclosure. A film composed of the first interlayer film for the laminated glass structure is also included in the present disclosure. The use of a film composed of the first interlayer film in the laminated glass structure is also included in the present disclosure.

[0161] [Light Control Film] The laminated glass structure has a light control film located between the first interlayer film and the second interlayer film.

[0162] Typically, light control films tend to deteriorate or lose their functionality when autoclaved under high-temperature and high-pressure conditions. However, the laminated glass structure of the present disclosure can be suitably produced even by autoclaving at low temperatures, allowing the light control film to be incorporated into the laminated glass structure without being deactivated. Therefore, the laminated glass structure of the present disclosure can effectively exhibit the functionality inherent to the light control film. Furthermore, since the light control film is provided with electronic wiring, a shielding printed portion, etc., complex steps (thickness differences) are likely to occur, which makes it easy for air to remain or bubbles to form between the interlayer film and the glass plate or light control film during pressure bonding. However, in the present disclosure, such air remaining and bubbles are sufficiently suppressed even when pressure bonding is performed at low temperatures, so the resulting laminated glass structure has excellent transparency and a good appearance. Furthermore, laminated glass structures (e.g., window glass) incorporating a light control film have high added value, such as excellent design.

[0163] For the light-control film, the explanation given in the section "1." [Functional Layer] above is applicable.

[0164] [Laminate Film] The laminated glass structure of the present disclosure, which is comprised of a first interlayer film, a light control film, and a second interlayer film, is useful for a variety of applications in addition to applications for providing laminated glass structures. Such a laminated film comprised of a first interlayer film, a light control film, and a second interlayer film is included in the present disclosure. A laminated film for the above-mentioned laminated glass structure, which is comprised of a first interlayer film, a functional layer, and a second interlayer film, is also included in the present disclosure. The use of a laminated film comprised of a first interlayer film, a functional layer, and a second interlayer film in the above-mentioned laminated glass structure is also included in the present disclosure.

[0165] The laminated film can be produced by, for example, thermocompression bonding a first interlayer film, a light control film, and a second interlayer film. When incorporating the laminated film into a laminated glass structure, the thermocompression bonding may be performed by first thermocompression bonding the first interlayer film, the light control film, and the second interlayer film to form a laminated film, and then pressing the laminated film to a glass plate to form the laminated glass structure. Alternatively, the first interlayer film, the light control film, and the second interlayer film before pressing may be disposed between two glass plates, and when pressing the glass plate and the laminated film together, the first interlayer film, the light control film, and the second interlayer film may also be pressed together.

[0166] Here, it is preferable to use a light control film with a smaller planar area than each interlayer film, and to arrange the first interlayer film, light control film, and second interlayer film so that each interlayer film is present around the light control film in a planar view (see, for example, Figures 2 and 3). In this case, it is preferable not to arrange a gap filler around the periphery of the light control film. The laminated glass structure of the present disclosure can be suitably manufactured without using a gap filler. In this way, the laminated glass structure obtained by pressure bonding has a region having the light control film and a region around the region not having the light control film, which is thinner than the region. This sufficiently suppresses moisture penetration from the edges, resulting in the laminated glass structure having excellent moisture resistance and allowing the functions derived from the light control film to be more effectively exhibited.

[0167] [Various Physical Properties] In the laminated glass structure of the present disclosure, the first glass plate, the first interlayer film, the light control film, the second interlayer film, and the second glass plate all have curved shapes with convex portions in the same direction. For example, taking the laminated glass structure shown in FIG. 1 as an example, the above shape refers to a shape in which the glass plates G1 and G2, the interlayer films F1 and F2, and the light control film all have convex portions in the same direction (e.g., downward in FIG. 1). The laminated glass structure has a first interlayer film with low rigidity and high flexibility, making it possible to realize various shapes. Furthermore, it is preferable that the radius of curvature of the inner surface (i.e., concave surface) of each glass plate, each interlayer film, and each light control film is 1,000 to 20,000 mm.

[0168] The laminated glass structure has an absolute value |a-b| of the difference between the thickness (a) of the region of the laminated glass structure that does not have a light control film and the thickness (b) of the central portion of the region that has the light control film, divided by the thickness (c) of the light control film, (|a-b| / c) of 0.1 to 0.5. This sufficiently suppresses moisture penetration from the edges, allowing the functions inherent to the light control film to be effectively exhibited even without a gap filler. The above (|a-b| / c) is preferably 0.15 or more, more preferably 0.17 or more, even more preferably 0.2 or more, and particularly preferably 0.22 or more. It is also preferably 0.4 or less, more preferably 0.3 or less.

[0169] The laminated glass structure also preferably has a thickness ratio (a / b) of 0.9 to 1.0 between the thickness (a) of the region of the laminated glass structure that does not have the light control film and the thickness (b) of the central portion of the region of the laminated glass structure that has the light control film. This sufficiently suppresses moisture penetration from the edges, allowing the functions inherent to the light control film to be exhibited more effectively. The thickness ratio (a / b) is more preferably 0.9 to 0.98.

[0170] Here, "the thickness (b) of the central part of the region of the laminated glass structure having the light control film" refers to the sum of the thicknesses of each layer at the location corresponding to the centroid of the light control film when the laminated glass structure is viewed in plan. Also, "the thickness (a) of the region of the laminated glass structure not having the light control film" refers to the sum of the thicknesses of each layer at the midpoint between any end E1 of the light control film and the end E2 of the laminated glass structure that is closest to the end E in the horizontal direction when the laminated glass structure is viewed in plan. There are multiple end E1s, not just one, but it is sufficient that the above (|a-b| / c) when measured at any of the points falls within the above-mentioned range. Similarly, it is preferable that the above a / b when measured at any of the end E1s falls within the above-mentioned range.

[0171] As described above in the section "1." [Various Physical Properties], the thickness of the laminated glass structure at its edges is preferably 99% or less of the thickness of the central portion of the laminated glass structure, and the visible light transmittance at a wavelength of 390 nm in the region of the laminated glass structure that does not have the light control film is preferably lower than the visible light transmittance at a wavelength of 390 nm in the central portion of the region of the laminated glass structure that has the light control film. Similarly, the maximum ultraviolet light transmittance at wavelengths of 370 to 400 nm is preferably 30% or less, and more preferably 20% or less.

[0172] [Method for manufacturing laminated glass structure] The laminated glass structure of the present disclosure is preferably manufactured by a method in which the above-described laminated film is placed between a pair of glass plates and bonded together by pressure to obtain a laminated glass structure. For details of the manufacturing method, the explanation given in the section "1." [Method for manufacturing laminated glass structure] above is incorporated herein by reference. The term "functional layer" should be read as "light control film."

[0173] [Uses] The laminated glass structure of the present disclosure can be used for a wide variety of uses. For details of the uses (e.g., preferred embodiments, etc.), refer to the explanation given in the section "1." [Uses] above.

[0174] 3. Laminated Glass Structure, Film, and Laminated Film of the Present Disclosures 3-1 to 3-9 As described above, the laminated glass structure of the present disclosure 3-1 includes, in this order, a first glass sheet, a first interlayer film, a GHLC film, a second interlayer film, and a second glass sheet, and the first interlayer film has a creep compliance of 6.0 × 10 at 90°C per layer. －５ Pa －１ Such a laminated glass structure can exhibit the functions inherent to the GHLC film without losing them, has a good appearance, and is highly safe.

[0175] The laminated glass structures, films, laminated films, etc. of Disclosures 3-1 to 3-9 will be described below. Note that the following mainly describes the characteristics unique to the laminated glass structures, etc. of Disclosures 3-1 to 3-9, and omits descriptions of matters that overlap with those described in "1." and "2." above.

[0176] [Layer structure] For details of the layer structure of the laminated glass structure and preferred embodiments thereof, the explanation given in the section "1." [Layer structure] above is to be cited (see also Fig. 1). The term "functional layer" shall be read as "GHLC film".

[0177] [Glass Plates] The laminated glass structure has a first glass plate and a second glass plate. Details and preferred embodiments of each glass plate are described in the section "1." [Glass Plates] above.

[0178] [Interlayer film] The laminated glass structure has at least a pair of interlayer films arranged to sandwich the light control film. One of the pair of interlayer films is referred to as a first interlayer film, and the other is referred to as a second interlayer film. The first interlayer film and the second interlayer film may have the same configuration as each other, or may be different.

[0179] The first interlayer film and the second interlayer film are preferably the same as the first interlayer film and the second interlayer film, respectively, of the laminated glass structure of the present disclosure 1-1. Therefore, as described in "1." [Interlayer film] above, the first interlayer film has a creep compliance of 6.0 × 10 per layer at 90°C. －５ Pa －１The above range is preferable, and more preferable ranges are as described above. For details and preferred aspects of each interlayer film (e.g., layer structure, creep compliance value, Tg, types and amounts of contained components, thickness, uneven shape, manufacturing method, etc.), the explanation given in the [Interlayer Film] section of "1." above is to be used. The term "functional layer" shall be read as "GHLC film."

[0180] The first interlayer film included in the laminated glass structure of the present disclosure (i.e., for example, an interlayer film having the creep compliance per interlayer film within a predetermined range) itself was discovered by the present inventors. That is, a film composed of the first interlayer film included in the laminated glass structure is also included in the present disclosure. A film composed of the first interlayer film for the laminated glass structure is also included in the present disclosure. The use of a film composed of the first interlayer film in the laminated glass structure is also included in the present disclosure.

[0181] GHLC Film The laminated glass structure has a GHLC film located between a first interlayer and a second interlayer.

[0182] Typically, GHLC films are prone to deterioration or deactivation of their functions when subjected to autoclaving under high-temperature and high-pressure conditions. Furthermore, temperature and pressure changes during compression, as well as thermal shrinkage of the interlayer, can cause color unevenness in the resulting laminated glass structure, making it unsuitable for practical use. However, the laminated glass structure of the present disclosure can be suitably produced even by autoclaving at low temperatures, allowing the GHLC film to be incorporated into the laminated glass structure without being deactivated. Therefore, the laminated glass structure of the present disclosure can effectively exhibit the functions inherent to the GHLC film while sufficiently suppressing the occurrence of color unevenness. Furthermore, because the GHLC film is provided with electronic wiring, a shielding printed portion, etc., complex steps (thickness differences) are likely to occur, which can lead to air remaining or bubbles forming between the interlayer and the glass plate or GHLC film during compression. However, in the present disclosure, such air remaining or bubbles are sufficiently suppressed even when compression is performed at low temperatures, resulting in a laminated glass structure with excellent transparency and a good appearance. Furthermore, a laminated glass structure (for example, window glass) incorporating a GHLC film has high added value, such as excellent design.

[0183] A GHLC film is a film-like component comprising a GHLC (Guest-Host Liquid Crystal). Specifically, the GHLC film preferably comprises two resin films and a GHLC layer disposed between the two resin films. A GHLC film having such a configuration has resin materials on the surfaces in contact with the first interlayer film and the second interlayer film, thereby improving adhesion to these interlayer films. The GHLC layer is composed of, for example, a liquid crystal composition in which a dichroic dye is dissolved as a guest in a host liquid crystal. The dichroic dye has a uniaxial light absorption axis and absorbs only light vibrating along the light absorption axis. Therefore, a GHLC film comprising a GHLC layer can change the orientation of the dichroic dye in accordance with the movement of the liquid crystal due to an electric field, thereby controlling the direction of the light absorption axis and thereby changing the transmission state of the liquid crystal layer.

[0184] The resin film used in the GHLC film is not particularly limited, and examples thereof include polyester resin films such as polyethylene terephthalate (PET) film and polyethylene naphthalate (PEN) film; (meth)acrylic resin film; triacetyl cellulose (TAC) film; polyethersulfone (PES) resin film; polyimide resin film; and the like. Among these, from the viewpoint of ease of handling, the resin film is preferably a polyester resin film, and more preferably a PET film. Each of the two resin films may be provided with a conductive layer constituting an electrode on the surface facing the GHLC layer.

[0185] To control the thickness (cell gap) of the GHLC layer, a spacer may be disposed between the two resin films. The spacer is not particularly limited and may be, for example, a bead spacer or a spacer formed from photoresist in, for example, a cylindrical shape. The shape of the spacer is not particularly limited and may be, for example, a spherical shape, a cylindrical shape, or a prismatic shape.

[0186] [Laminate Film] The laminated glass structure of the present disclosure, which comprises a first interlayer film, a GHLC film, and a second interlayer film, is useful for a variety of applications in addition to applications for providing laminated glass structures. Such a laminated film comprising a first interlayer film, a GHLC film, and a second interlayer film is included in the present disclosure. A laminated film for the above-mentioned laminated glass structure, comprising a first interlayer film, a functional layer, and a second interlayer film, is also included in the present disclosure. The use of a laminated film comprising a first interlayer film, a functional layer, and a second interlayer film in the above-mentioned laminated glass structure is also included in the present disclosure.

[0187] The laminated film can be produced by, for example, thermocompression bonding a first interlayer film, a GHLC film, and a second interlayer film. When the laminated film is incorporated into a laminated glass structure, the thermocompression bonding may be performed by first thermocompression bonding the first interlayer film, the GHLC film, and the second interlayer film to form a laminated film, and then pressing the laminated film to a glass plate to form the laminated glass structure. Alternatively, the first interlayer film, the GHLC film, and the second interlayer film before pressing may be disposed between two glass plates, and the first interlayer film, the GHLC film, and the second interlayer film may also be pressed when pressing the glass plate and the laminated film together.

[0188] Here, it is preferable to use a GHLC film having a smaller planar area than each of the interlayer films, and to arrange the first interlayer film, the GHLC film, and the second interlayer film so that each interlayer film is present around the GHLC film in a plan view (see, for example, Figures 2 and 3). In this case, it is not necessary to arrange a gap filler around the periphery of the GHLC film.

[0189] [Method for manufacturing laminated glass structure] The laminated glass structure of the present disclosure is preferably manufactured by a method in which the above-described laminated film is placed between a pair of glass plates and bonded together by pressure to obtain a laminated glass structure. For details of the manufacturing method, the explanation given in the section "1." [Method for manufacturing laminated glass structure] above is incorporated herein by reference. The term "functional layer" shall be read as "GHLC film."

[0190] [Various Physical Properties] In the laminated glass structure of the present disclosure, the first glass plate, the first interlayer film, the GHLC film, the second interlayer film, and the second glass plate preferably have curved shapes with convex portions in the same direction. For details, the contents of "1." and "2." above are incorporated by reference. It is preferable that the radius of curvature of the inner surface (i.e., concave surface) of each glass plate, each interlayer film, and each GHLC film is 1,000 to 20,000 mm.

[0191] As described in the section "1." [Various Physical Properties] above, the thickness of the laminated glass structure at its edges is preferably 99% or less of the thickness of the central part of the laminated glass structure taken as 100%, and the maximum value of the ultraviolet transmittance at wavelengths of 370 to 400 nm is preferably 30% or less, more preferably 20% or less.

[0192] [Method for manufacturing laminated glass structure] The laminated glass structure of the present disclosure is preferably manufactured by a method in which the above-described laminated film is placed between a pair of glass plates and bonded together by pressure to obtain a laminated glass structure. For details of the manufacturing method, the explanation given in the section "1." [Method for manufacturing laminated glass structure] above is incorporated herein by reference. The term "functional layer" shall be read as "GHLC film."

[0193] Here, in the manufacturing method of the laminated glass structure of the present disclosure, the lamination (also referred to as lamination or main lamination) is preferably performed under low-temperature conditions, and more preferably under low-temperature and low-pressure conditions. By performing the lamination under low-temperature or low-pressure conditions, deterioration or deactivation of the GHLC film is sufficiently prevented. Furthermore, even when a functional member or the like is attached to the glass plate, deterioration or deactivation of the member is sufficiently prevented. Furthermore, from the viewpoint of further preventing deterioration or deactivation of the GHLC film or the like, the preliminary bonding (also referred to as temporary pressure bonding or preliminary lamination) is also preferably performed under low-temperature conditions, and more preferably under low-temperature and low-pressure conditions. The preferred conditions for main lamination and preliminary lamination, such as temperature and pressure, have been described above, and will not be described here.

[0194] [Uses] The laminated glass structure of the present disclosure can be used for a wide variety of uses. For details of the uses (e.g., preferred embodiments, etc.), refer to the explanation given in the section "1." [Uses] above.

[0195] 4. Interlayer Films for Laminated Glass, Laminated Films, and Laminated Glass Constructs, etc. of the Present Disclosures 4-1 to 4-10 As described above, the interlayer film for laminated glass of the present disclosure 4-1 contains a polyvinyl acetal resin, has an uneven shape on at least one surface, and has a remaining embossing distance calculated by the above-mentioned <Method for Calculating Remaining Embossing Distance> of less than 27 mm. Such an interlayer film for laminated glass has excellent adhesion to various adherends and can suitably provide a laminated glass construct that has good appearance and high safety.

[0196] The interlayer films for laminated glass, laminated films, laminated glass constructs, etc. of Disclosures 4-1 to 4-10 will be described below. Note that the following mainly describes the characteristics unique to the interlayer films for laminated glass, etc. of Disclosures 4-1 to 4-10, and omits explanations of matters that overlap with those described in "1." to "3." above.

[0197] [Interlayer Film for Laminated Glass] The interlayer film for laminated glass according to the present disclosure contains a polyvinyl acetal resin, has at least one surface with an uneven shape, and has an embossing remaining distance of 30 mm or less (preferably less than 27 mm) calculated by the method described above. When measuring the transmittance along the center line, the transmittance is measured over a 5 mm wide area centered on the center line in a plan view (see, for example, Figure 4 described below). The transmittance is measured using a glass transmittance meter "MJ-TM110 (separate sensor type)" (Sato Shoji).

[0198] An interlayer film for laminated glass containing a polyvinyl acetal resin, having at least one surface with an uneven shape and a residual embossing distance within a predetermined range, exhibits high adhesion to various adherends, such as glass plates. Therefore, by using this interlayer film for laminated glass, residual air and foaming can be suppressed during pressure bonding to glass plates, etc., without the need for an autoclave process under high-temperature and high-pressure conditions or the use of a gap filler, and a laminated glass structure with a good appearance can be efficiently obtained. Furthermore, when a functional layer is laminated on the interlayer film for laminated glass to obtain a laminated glass structure, the effects derived from the functional layer can be effectively exhibited. From the viewpoint of further exhibiting these effects, the residual embossing distance is preferably 26 mm or less, and even more preferably 25 mm or less.

[0199] Here, the remaining embossing distance can be easily adjusted to within the above range by appropriately adjusting, for example, the amount of hydroxyl groups contained in the polyvinyl acetal resin, the weight-average molecular weight and stereoregularity of the polyvinyl acetal resin, the surface roughness of the interlayer film for laminated glass, and the like.

[0200] When the interlayer film for laminated glass is a multilayer film, it is preferable that the remaining embossing distance falls within the above range when the entire multilayer film is subjected to the above method as a sample.

[0201] The details and preferred embodiments of the interlayer film for laminated glass are preferably substantially the same as those of the first interlayer film (or the second interlayer film) of the laminated glass structure of the present disclosure 1-1. Therefore, as described in "1." [Interlayer film] above, the interlayer film for laminated glass has a creep compliance of 6.0 × 10 per layer at 90°C. －５ Pa －１ The above range is preferable, and more preferable ranges are as described above.

[0202] The interlayer film for laminated glass according to the present disclosure contains a polyvinyl acetal resin. That is, the interlayer film for laminated glass has a resin layer containing a polyvinyl acetal resin. Such an interlayer film for laminated glass has good adhesion to various adherends (e.g., functional layers, glass plates, etc.), and its use can provide a laminated glass structure with excellent impact resistance, etc. Furthermore, by adjusting the weight-average molecular weight, glass transition temperature, and / or intermolecular interactions of the polyvinyl acetal resin used, it is easy to adjust the creep compliance per layer within a predetermined range. When the interlayer film for laminated glass is a multilayer film, it is preferable that at least the layer satisfying the creep compliance value is the resin layer. Each of the components contained in the interlayer film for laminated glass may be used alone, or two or more may be used in combination. The interlayer film for laminated glass may also contain a thermoplastic resin other than the polyvinyl acetal resin.

[0203] The interlayer film for laminated glass of the present disclosure preferably further contains a plasticizer. That is, the resin layer preferably further contains a plasticizer. By including a plasticizer in addition to the polyvinyl acetal resin in the interlayer film for laminated glass, the interlayer film becomes more flexible, thereby improving the adhesion of the interlayer film to various substrates and the penetration resistance of the laminated glass structure obtained using the interlayer film. Furthermore, adjusting the type and content of the plasticizer makes it easier to adjust the creep compliance per interlayer film layer within a predetermined range.

[0204] Other preferred aspects of the interlayer film for laminated glass (e.g., layer structure, creep compliance value, Tg, types and amounts of contained components, thickness, uneven shape, manufacturing method, etc.) are described in the above section "1." [Interlayer film] by reference. "(First or second) interlayer film" shall be read as "the interlayer film for laminated glass of the present disclosure."

[0205] [Laminate Film] The laminate film of the present disclosure has a structure in which the interlayer film for laminated glass of the present disclosure described above and a functional layer are laminated. For example, the laminate film of the present disclosure has a structure in which a functional layer is sandwiched between a first interlayer film and a second interlayer film, and at least one of the first interlayer film and the second interlayer film is the interlayer film for laminated glass of the present disclosure described above. The first interlayer film and the second interlayer film may have the same configuration as each other, or may be different. Furthermore, it is preferable that both the first interlayer film and the second interlayer film are the interlayer film for laminated glass of the present disclosure described above.

[0206] The explanation for the functional layer is given in the section "1." [Functional Layer] above. As described in that section, films equipped with electronic components typically tend to deteriorate or lose their functionality when subjected to autoclaving under high-temperature and high-pressure conditions. However, by using the interlayer film for laminated glass of the present disclosure, a laminated glass structure can be suitably produced even by autoclaving at low temperatures, and the functional layer can be incorporated into the laminated glass structure without being lost to deactivation. Therefore, a laminated glass structure equipped with the laminated film of the present disclosure can effectively exhibit the functionality inherent to the functional layer.

[0207] The laminated film can be produced by, for example, thermocompression bonding a first interlayer film, a functional layer, and a second interlayer film. When the laminated film is incorporated into a laminated glass structure, the thermocompression bonding may be performed by first thermocompression bonding the first interlayer film, the functional layer, and the second interlayer film to form a laminated film, and then pressing the laminated film to a glass plate to form the laminated glass structure. Alternatively, the first interlayer film, the functional layer, and the second interlayer film before pressing may be disposed between two glass plates, and when the glass plate and the laminated film are pressed together, the first interlayer film, the functional layer, and the second interlayer film may also be pressed together.

[0208] Here, it is preferable to use a functional layer having a smaller planar area than each interlayer film, and to arrange the first interlayer film, functional layer, and second interlayer film so that each interlayer film is present around the functional layer in a plan view (see, for example, Figures 2 and 3). In this case, it is not necessary to arrange a gap filler around the periphery of the functional layer. By using the interlayer film for laminated glass of the present disclosure, a laminated glass structure can be suitably produced without using a gap filler.

[0209] [Laminated Glass Assembly] The laminated glass assembly of the present disclosure has a structure in which the laminated film of the present disclosure described above is sandwiched between a pair of glass plates. For example, the laminated glass assembly includes a first glass plate, a first interlayer film, a functional layer, a second interlayer film, and a second glass plate, in this order. The laminated glass assembly may further include one or more optional layers between the respective layers, or may include two or more functional layers.

[0210] (Layer Structure) For details of the layer structure of the laminated glass structure and preferred embodiments thereof, the explanation given in the section "1." [Layer Structure] above is incorporated herein by reference (see also Figure 1). In Figure 1, at least one of the interlayer films F3, F4, and F5 is an interlayer film for laminated glass according to the present disclosure.

[0211] (Glass Plates) The laminated glass structure has a first glass plate and a second glass plate. Details and preferred embodiments of each glass plate are described in the section "1." [Glass Plates] above.

[0212] (Production method) The laminated glass structure of the present disclosure is preferably produced by a method in which the above-described laminated film is placed between a pair of glass plates and bonded together by pressure to obtain a laminated glass structure. Details of the production method are as described above in the section "1." [Production method of laminated glass structure].

[0213] (Applications) The laminated glass structure of the present disclosure can be used for a wide variety of applications. For details of the applications (e.g., preferred embodiments, etc.), refer to the explanation given in the above section "1." [Applications].

[0214] 5. Interlayer Films for Laminated Glass, Laminated Films, and Laminated Glass Constructs, etc. of the Present Disclosures 5-1 to 5-12 As described above, the interlayer film for laminated glass of the present disclosure 5-1 contains a polyvinyl acetal resin, and has an exposed film area of ​​90 area% or less, calculated by the above-mentioned <Method for Calculating Exposed Film Area>. Such an interlayer film for laminated glass can suitably provide a laminated glass construct that has good appearance and high safety.

[0215] The interlayer films for laminated glass, laminated films, laminated glass constructs, etc. of the present disclosures 5-1 to 5-12 will be described below. Note that the following mainly describes the unique features of the interlayer films for laminated glass, etc. of the present disclosures 5-1 to 5-12, and omits explanations of matters that overlap with those described in "1." to "4." above.

[0216] [Interlayer Film for Laminated Glass] The interlayer film for laminated glass of the present disclosure contains a polyvinyl acetal resin and has an exposed film area of ​​90% or less by area, calculated by the method described above. This exposed film area is preferably 88% or less by area, and more preferably 85% or less by area. The lower limit of the exposed film area is 0% by area. Here, for example, clear glass (product name: "Float Plate Glass") manufactured by Sanshiba Glass Materials Co., Ltd. is used as the float glass sheet, and a constant temperature pressurizing device "HP-55-MAH-H14" manufactured by Kyoshin Engineering Co., Ltd. is used as the autoclave. The hammer has a length of 313 mm from the rotation axis to the striking surface, and the striking surface is a protruding surface with a diameter of 30 mm and a length of 20 mm. Image capture and analysis of the captured image (referred to as image analysis) are performed, for example, as follows.

[0217] (Image capture) ・Device: Rigaku Corporation, 3D micro X-ray CT for veterinary clinics "StellaScan AX" ・Measurement conditions Tube voltage: 80 kV Tube current: CT / Live 250 uA FOV: 30 mm Capture size: Large Shooting time: 2.5 min Magnification: 1.67x Pixel size: 83.2 um / pixel

[0218] After impact, the optical laminate is placed in a bag with a zipper to prevent glass from scattering, and the bag is used for image capture. At this time, a spacer or the like may be used to fix the measurement position. When measuring with the above device, the bag is fixed so that the entire impact surface is included in the X-ray irradiation area, and measurement is performed under the above conditions with Binning 1 set. After measurement is completed, an image is acquired by reconstructing the entire range.

[0219] (Image Analysis) The images obtained as described above are analyzed using image analysis software Avizo 3D Pro 2023.1.1 (manufactured by Thermo Fisher Scientific) and open source image analysis software Fiji (ImageJ) according to the following procedure.

[0220] (i) Image cropping Using Avizo 3D Pro 2023.1.1, the "Crop Editor" is applied to the acquired image, and adjustments are made so that a region within at least 10 mm of the edge of the test piece and a region that does not include unstruck regions are extracted. The image size after cropping is, for example, x = 1600, y = 496, z = 900. The XZ cross section is a cross section parallel to the surface of the optical laminate (i.e., a cross section perpendicular to the thickness direction).

[0221] (ii) Extraction of Test Piece "Interactive Thresholding" is applied to the image (i) above (i.e., the image cut out in (i) above), and the threshold is adjusted so that the test piece (i.e., the region of the glass piece and the interlayer film for laminated glass) is extracted. Next, "Closing" and "Remove Small Spots" are applied to remove noise from the extracted region. The conditions for each analysis module are, for example, as follows: Interactive Thresholding Intensity Range: 16000-65535 Closing Size: 3 Other conditions are set to their default values. Remove Small Spots Size: 1000 Other conditions are set to their default values.

[0222] (iii) Dividing the front and back regions of the test piece Apply "Invert" to the image in (ii) above to invert the extracted region. Then, apply "Separate Objects" to divide the region using the test piece as the boundary. The conditions for each analysis module are, for example, as follows: - Invert: Set to the initial value. - Separate Objects Marker Extent: 20 Other conditions are set to the initial values.

[0223] (iv) Extraction of image edges in XZ cross sections: A new label is created by applying "Add a new label field" in "Segmentation Editor" to the image in (i) above. After creating the label, the screen display is switched to the XZ cross section. After that, the entire region is selected in the first and last images at the slice position, and then "Add" in "SELECTION" is applied to extract only the image edges in the XZ cross section.

[0224] (v) Identification of the front and back regions of the test piece Apply "OR Image" to the image (iii) above, and add the extracted region of the image (iv) above to the extracted region of the image (iii) above. Then, apply "Labeling" and "Dilation" to identify the front and back regions of the test piece, respectively. The conditions for each analysis module are, for example, as follows: Labeling - Set to the initial value. Dilation Size: 1 Other conditions are set to the initial values.

[0225] (vi) Extraction of Glass Fragments "Interactive Thresholding" is applied to the image in (i) above, and the threshold is adjusted so that glass fragments are extracted. Next, "Remove Small Spots" is applied to remove noise from the extracted region. The conditions for each analysis module are, for example, as follows: Interactive Thresholding Intensity Range: 26000-65535 Remove Small Spots Size: 10 Other conditions are set to their default values.

[0226] (vii) Glass piece volume analysis of the test piece surface region "Interactive Thresholding" is applied to the image of (v) above to extract the surface region of the test piece. Next, "AND Image" is applied to extract the region overlapping with the extracted region of (vi) above. After that, "Label Analysis" is applied to analyze the volume (voxel) of each glass piece extracted region. The conditions of each analysis module are, for example, as follows: Interactive Thresholding Intensity Range: 1-1 Label Analysis Initial value.

[0227] (viii) Calculation of the film exposed area ratio of the test piece surface region Using Fiji, "Threshold" and "Subtract" are applied to the image obtained in (vii) above to extract the glass region of the test piece and set the brightness value of that region to "1". Next, "Reslice" and "Zprojection" are applied to change the orientation of the image and convert it into a two-dimensional image with integrated brightness values. Next, "Threshold" is applied to extract the glass interlayer film region. Then, "Set Measurements" and "Measure" are applied to measure the film exposed area. The conditions for each analysis module are, for example, as follows: Threshold (first) Lower threshold level: 1 Upper threshold level: 65535 Subtract Value: 254 Reslice Start at: Top Zprojection Start slice: 1 Stop slice: 496 Projection type: Sum Slices Threshold (second) Lower threshold level: 0 Upper threshold level: 0 Check Set Measurements Area Then, the film exposed area ratio was calculated from the obtained film exposed area using the following formula: It is calculated based on the following formula: Film exposed area ratio (%)=film exposed area (pixel) / {image size x (pixel)×image size z (pixel)}×100. The resolution is a value specified by the device.

[0228] (ix) Glass fragment volume analysis of the back region of the test piece "Interactive Thresholding" was applied to the image (v) above to extract the back region of the test piece. Next, "AND Image" was applied to extract the region overlapping with the extracted region (vi) above. Then, "Label Analysis" was applied to analyze the volume (voxel) of each glass fragment extracted region. The conditions for each analysis module are, for example, as follows: Interactive Thresholding Intensity Range: 2-2 Label Analysis Initial value.

[0229] (x) Extraction of glass pieces from the back area of ​​the test piece "Interactive Thresholding" is applied to the image in (v) above to extract the front area of ​​the test piece. Next, "AND Image" is applied to extract the area that overlaps with the extracted area in (vi) above. After that, "Export Data As..." is applied to output the extracted image. The conditions for each analysis module are, for example, as follows: Interactive Thresholding Intensity Range: 2-2

[0230] (xi) Calculation of the exposed film area ratio of the back region of the test piece Using Fiji, "Threshold" and "Subtract" are applied to the image obtained in (x) above to extract the glass region of the test piece and set the brightness value of that region to "1". Next, "Reslice" and "Zprojection" are applied to change the orientation of the image and convert it into a two-dimensional image with integrated brightness values. Next, "Threshold" is applied to extract the glass interlayer film region. Then, "Set Measurements" and "Measure" are applied to measure the exposed film area. The conditions for each analysis module are, for example, as follows: Threshold (first) Lower threshold level: 1 Upper threshold level: 65535 Subtract Value: 254 Reslice Start at: Top Zprojection Start slice: 1 Stop slice: 496 Projection type: Sum Slices Threshold (second) Lower threshold level: 0 Upper threshold level: 0 Check Set Measurements Area Then, the film exposed area ratio was calculated from the obtained film exposed area using the following formula: The calculation is based on the following formula: Film exposed area ratio (%)=film exposed area (pixel) / {image size x (pixel)×image size z (pixel)}×100.

[0231] Here, the exposed area of ​​the interlayer film for laminated glass can be easily adjusted within the above range by appropriately adjusting, for example, the amount of hydroxyl groups contained in the polyvinyl acetal resin, the metal salt content (e.g., the content of the Mg-based adhesion modifier described below), the weight-average molecular weight of the polyvinyl acetal resin, the stereoregularity, the surface roughness of the interlayer film for laminated glass, etc. Conventional interlayer films for laminated glass may contain magnesium (Mg) salts as adhesion modifiers, such as magnesium acetate, magnesium propionate, magnesium butyrate, magnesium 2-ethylbutyrate, magnesium 2-ethylhexanoate, magnesium octoate, magnesium decanoate, magnesium neodecanoate, and magnesium salts of carboxylic acids having 1 to 16 carbon atoms. However, the interlayer film for laminated glass of the present disclosure preferably does not contain these Mg-based adhesion modifiers. Specifically, the content of the Mg-based adhesion modifier is preferably less than 1 mass%, and more preferably less than 0.5 mass%, of the total amount (100 mass%) of the interlayer film for laminated glass of the present disclosure.

[0232] When the interlayer film for laminated glass is a multilayer film, it is preferable that at least one layer contains a polyvinyl acetal resin, and when only that layer is subjected to the above method as a sample, the exposed film area falls within the above range. It is particularly preferable that at least one layer of the multilayer film contains a polyvinyl acetal resin, and when the entire multilayer film is subjected to the above method as a sample, the exposed film area falls within the above range. When the interlayer film for laminated glass has multiple layers, the number of layers is not particularly limited, but may be, for example, two or three layers.

[0233] The interlayer film for laminated glass is preferably the same as the interlayer film for laminated glass described above in Disclosure 4-1. Therefore, the details and preferred embodiments of the interlayer film for laminated glass (e.g., layer structure, creep compliance value, Tg, types and amounts of contained components, thickness, uneven shape, manufacturing method, etc.) are described in the above section "4." [Interlayer film for laminated glass] by reference.

[0234] [Laminate Film] The laminate film of the present disclosure has a structure in which the interlayer film for laminated glass of the present disclosure described above and a functional layer are laminated. For example, the laminate film of the present disclosure has a structure in which a functional layer is sandwiched between a first interlayer film and a second interlayer film, and at least one of the first interlayer film and the second interlayer film is the interlayer film for laminated glass of the present disclosure described above. The first interlayer film and the second interlayer film may have the same configuration as each other or may be different. It is also preferable that both the first interlayer film and the second interlayer film are the interlayer film for laminated glass of the present disclosure described above. For other explanations regarding the laminate film (e.g., the functional layer, the manufacturing method of the laminate film, and the manner in which the laminate film is incorporated into a laminated glass construct), the explanations given in the section "4." [Laminate Film] above are incorporated by reference.

[0235] [Laminated Glass Assembly] The laminated glass assembly of the present disclosure has a structure in which the laminated film of the present disclosure described above is sandwiched between a pair of glass plates. For example, the laminated glass assembly includes a first glass plate, a first interlayer film, a functional layer, a second interlayer film, and a second glass plate, in this order. The laminated glass assembly may further include one or more optional layers between the respective layers, or may include two or more functional layers. For details and preferred embodiments of the laminated glass assembly of the present disclosure (e.g., layer structure, glass plates, manufacturing method, and uses), the explanations given in the above section "4." [Laminated Glass Assembly] are incorporated by reference.

[0236] The present disclosure will be described in more detail with reference to examples, but the present disclosure is not limited to these examples. Unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass". The weight average molecular weight of the resin, the Tg of the film, and the creep compliance at 90°C per film layer were determined according to the methods described above. The exposed area of ​​the film was also determined according to the method described above (clear glass (product name: "Float Plate Glass", thickness 3 mm) manufactured by Sanshiba Glass Materials Co., Ltd. was used as the float plate glass, and image capture and image analysis were performed under the conditions described above).

[0237] <Materials, etc.> The materials or members used are as follows: (1) Glass Plate Glass plate: manufactured by Sanshiba Glass Materials Co., Ltd., trade name "Float Plate Glass", size 30 cm x 30 cm x 3 mm

[0238] (2) Light Control Film Light Control Film 1 A 0.4 mm thick light control film (referred to as light control film 1) was used as one of the PDLC films. Light control film 1 has a structure in which a layer in which ITO is formed on a PET substrate, a PDLC layer, and a layer in which ITO is formed on a PET substrate are laminated in this order. Here, the thickness of the PDLC layer is 20 μm. A layer in which ITO is formed on a PET substrate (thickness 188 μm) was used as the transparent electrode layer.

[0239] Light-controlling film 2 A light-controlling film with a thickness of 0.17 mm (referred to as light-controlling film 2) was used as one of the PDLC films. Light-controlling film 2 has a structure in which a PET layer with ITO formed thereon, a PDLC layer, and a PET layer with ITO formed thereon are laminated in this order. The thickness of the PDLC layer is 20 μm. In addition, a layer in which ITO is formed on a PET substrate was used as the transparent electrode layer.

[0240] GHLC Film A 0.4 mm thick GHLC film was used as one of the GHLC films, which has a laminated structure of a PET substrate, a transparent electrode layer, an LC layer, another transparent electrode layer, and a PET substrate.

[0241] (3) PET substrate for evaluation tests 1, 2, 4, or 5 described below: Toray Industries, Inc., product name "Lumirror (registered trademark) T60", film thickness 188 μm

[0242] (4) Thermoplastic Resin Preparation Example A1 (Resin 1) In a reactor equipped with a stirrer, 1800 ml of ion-exchanged water, 150 g of polyvinyl alcohol A (average degree of polymerization 1700, degree of saponification 99 mol%), and 50 g of polyvinyl alcohol B (average degree of polymerization 800, degree of saponification 99 mol%) were placed and heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, this solution was cooled and the temperature was adjusted to 40 ° C., and then 30% hydrochloric acid was added as a catalyst so that the hydrochloric acid concentration was 0.9% by mass. The temperature was then adjusted to 20 ° C., and n-butyl aldehyde was added to 15 mol% while stirring. Thereafter, the solution was adjusted to 13 ° C., and n-butyl aldehyde was added to 54.7 mol%, resulting in the precipitation of a white particulate polyvinyl butyral resin. Twenty minutes after the second addition of n-butylaldehyde, 30% hydrochloric acid was added so that the hydrochloric acid concentration became 1.1% by mass, and the temperature was then raised to 48°C and the mixture was aged for 2 hours at an aging temperature of 48°C. The solution was then cooled and neutralized, and the polyvinyl butyral resin was washed with water and dried to obtain Resin 1 (polyvinyl butyral resin, hydroxyl group amount 30.9 mol%, acetalization degree 68.1 mol%, acetylation degree 0.99 mol%, weight average molecular weight 245,000).

[0243] Preparation Example A2 (Resin 2) 1800 ml of ion-exchanged water and 200 g of polyvinyl alcohol A (average polymerization degree 1700, saponification degree 99 mol%) were placed in a reactor equipped with a stirrer, and the mixture was heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, 30% hydrochloric acid was added as a catalyst to this solution so that the hydrochloric acid concentration was 0.2% by mass, and the temperature was adjusted to 15 ° C., and then n-butyl aldehyde was added to 10 mol% while stirring. Then, n-butyl aldehyde was added to 60 mol%, resulting in the precipitation of a white granular polyvinyl butyral resin. 10 minutes after precipitation, 30% hydrochloric acid was added so that the hydrochloric acid concentration was 1.8% by mass, and then the temperature was raised to 53 ° C. and the mixture was aged at an aging temperature of 53 ° C. for 2 hours. Next, the solution was cooled and neutralized, and then the polyvinyl butyral resin was washed with water and dried to obtain Resin 2 (polyvinyl butyral resin, hydroxyl group content 31.5 mol%, acetalization degree 67.8 mol%, acetylation degree 0.7 mol%, weight average molecular weight 267,000).

[0244] Preparation Example A3 (Resin 3) Resin 3 was obtained in the same manner as Preparation Example A2 (Resin 2), except that it was aged for 2 hours at an aging temperature of 63°C instead of 2 hours at the aging temperature of 53°C as in Resin 2. Resin 3 (polyvinyl butyral resin, hydroxyl group content 30.1 mol%, acetalization degree 69.2 mol%, acetylation degree 0.67 mol%, weight average molecular weight 262,000) was obtained.

[0245] (5) Plasticizer 3GO: triethylene glycol-bis-(2-ethylhexanoate), manufactured by Sekisui Chemical Co., Ltd., molecular weight 402 TG-1000R: polyoxypropylene glyceryl ether, manufactured by NOF Corporation, trade name “UNIOL TG-1000R”, molecular weight 1000

[0246] <Interlayer Film> Preparation Example B1 (Film 1) 40 parts of plasticizer (3GO) were mixed with 100 parts of Resin 1 to obtain a resin composition. The obtained resin composition was fed into a twin-screw extruder to produce a film-like Film 1 having a thickness of 760 μm. The Tg and creep compliance J(t) at 90 ° C. per layer of the obtained Film 1 were measured. The results are shown in Table 1.

[0247] Preparation Example B2 (Membrane 2) A film-like membrane 2 having a thickness of 760 μm was prepared in the same manner as in Preparation Example B1, except that Resin 2 was used instead of Resin 1. The Tg and creep compliance J(t) at 90° C. of the obtained membrane 2 were measured. The results are shown in Table 1.

[0248] Preparation Example B3 (Membrane 3) A film-like membrane 3 having a thickness of 760 μm was prepared in the same manner as in Preparation Example B1, except that Resin 3 was used instead of Resin 1. The Tg and creep compliance J(t) at 90° C. of the obtained membrane 3 were measured. The results are shown in Table 1.

[0249] Preparation Example B4 (Membrane 4) A film-like membrane 4 having a thickness of 380 μm was prepared in the same manner as Preparation Example B1, except that Resin 3 was used instead of Resin 1. The creep compliance J(t) of the obtained membrane 4 at 90° C. was measured. The results are shown in Table 1.

[0250]

[0251] <Laminated Glass Structure> Example 1 Two glass plates, two films 1, and a light control film 1 were prepared. One film 1, a light control film 1, and another film 1 were laminated in this order on one glass plate, and the other glass plate was then laminated on top of that to obtain a laminate 1. As shown in Figures 2 and 3, the glass plate and film 1 each had a planar size of 300 mm x 300 mm, and the light control film 1 had a planar size of 200 mm x 200 mm. They were arranged so that the centroids of the glass plate, film 1, and light control film 1 overlapped in plan view. Figure 2 is a schematic side view of the layer structure of the laminate 1, and Figure 3 is a schematic plan view of the laminate 1.

[0252] The laminate 1 was placed in a vacuum laminator "LAMINATOR 0505S" manufactured by Nisshinbo Mechatronics Inc. and degassed for 5 minutes at 90°C and a vacuum of 4 kPa. Next, while still degassed at 90°C, a pressure of 100 kPa was applied to the laminate 1 using a medium-speed press (pressure increase rate: 2 kPa / s), and then the laminate was held at 90°C and 100 kPa for 3 minutes. The laminate was then pressure-bonded for 20 minutes using an autoclave at 140°C and 1.3 MPa, to obtain a laminated glass structure 1. The laminated glass structure 1 had a good appearance and was highly transparent.

[0253] Example 2 A laminated glass structure 2 was obtained in the same manner as in Example 1, except that light control film 2 was used instead of light control film 1. The laminated glass structure 2 also had a good appearance and high transparency.

[0254] Example 3 Two glass plates, Film 1, Film 3, and light control film 2 were prepared. Film 1, light control film 2, and Film 3 were superimposed in this order on one of the glass plates, and the other glass plate was further superimposed thereon to obtain laminate 3. Thereafter, laminated glass structure 3 was obtained in the same manner as in Example 1. Laminated glass structure 3 also had a good appearance and high transparency.

[0255] Example 4 A laminated glass structure 4 was obtained in the same manner as in Example 2, except that film 2 was used instead of film 1 disposed on both sides of the light control film 2. The laminated glass structure 4 also had a good appearance and high transparency.

[0256] Example 5 A laminated glass structure 5 was obtained in the same manner as in Example 1, except that film 2 was used instead of film 1 arranged on both sides of light control film 1, and light control film 2 was used instead of light control film 1.

[0257] Example 6 Two glass plates, two films 1, and a GHLC film were prepared. One film 1, a GHLC film, and another film 1 were stacked in this order on one glass plate, and then the other glass plate was stacked on top of that to obtain a laminate. As shown in Figures 2 and 3, the glass plate and film 1 each had a planar size of 300 mm x 300 mm, and the GHLC film had a planar size of 200 mm x 200 mm. The glass plate, film 1, and GHLC film were arranged so that their centroids overlapped in plan view. Figure 2 is also a schematic side view of the layer structure of the laminate, and Figure 3 is a schematic plan view of the laminate.

[0258] The obtained laminate was placed in a rubber bag, which was a vacuum bag, and degassed for 5 minutes at a vacuum pressure of 0.09 MPa. Next, while still degassed, the laminate was heated to 75°C at a temperature increase rate of 2°C / min and then cooled to 30°C. The pressure was then returned to normal. Thereafter, the laminate was held in an autoclave at 100°C and 0.3 MPa for 20 minutes, cooled, and then returned to normal pressure. In this way, a laminated glass structure 6 was obtained.

[0259] Example 7 Laminated glass structure 7 was obtained in the same manner as in Example 6, except that Film 2 was used instead of Film 1 disposed on both sides of the GHLC film.

[0260] Comparative Example 1 A laminated glass structure C1 was obtained in the same manner as in Example 1, except that instead of the film 1 disposed on both sides of the light control film 1, a film 3 was used.

[0261] Comparative Example 2 Two glass plates, two films 3, a light control film 1, and a gap filler were prepared. A test piece with a planar size of 300 mm x 300 mm was cut from a 380 μm-thick film 4 as the gap filler, and the inner surface of the test piece was cut out so that a 200 mm x 200 mm portion of the light control film 1 fit into the test piece. One film 1, the light control film 1, the gap filler arranged so that the light control film 1 fits inside, and the other film 1 were stacked in this order on one glass plate, and then the other glass plate was stacked on top of them to obtain a laminate. The glass plate and film 1 each had a planar size of 300 mm x 300 mm, and the light control film 1 had a planar size of 200 mm x 200 mm. They were arranged so that the centroids of the glass plate, film 1, and light control film 1 overlapped in plan view. A laminated glass structure C2 was obtained in the same manner as in Example 1, except that this laminate was used.

[0262] Comparative Example 3 A laminated glass structure C3 was obtained in the same manner as in Example 6, except that Film 3 was used instead of Film 1 disposed on both sides of the GHLC film.

[0263] <Evaluation Test 1> The following evaluation test was carried out using each of the laminated glass structures obtained in Examples 1 to 4 and Comparative Example 1. The results are shown in Table 2. Table 2 also lists the types of interlayer films and functional layers constituting each laminated glass structure (glass plates are omitted).

[0264] (Evaluation of Distortion and Deflection of Laminated Glass) Laminated glass assemblies corresponding to the laminated glass assemblies obtained in Examples 1 to 4 and Comparative Example 1 were prepared (see also Figures 2 and 3). Here, since using the light control film as is would make the measurement complicated, a PET substrate was used instead of the light control film. That is, the PET substrate, which accounts for most of the thickness of light control film 1 or 2, was used to resemble light control film 1 or 2. A PET substrate (188 μm) was used instead of light control film 2 (thickness 170 μm), and a laminate of two PET substrates (188 μm) was used instead of light control film 1 (thickness 400 μm). The planar size of the PET substrate was the same as that of light control films 1 and 2. Therefore, the layer structure of the laminated glass assemblies used in this evaluation test corresponds to the functional layer Z in Figures 2 and 3 replaced with one or two PET substrates.

[0265] Then, assuming that the refractive index of each layer was 1.5, the thickness of each layer was measured using an "OptiGauge" multilayer film thickness measuring device manufactured by Lumetrics, Inc., USA, and then the thickness difference X was calculated. Note that when it is difficult to conduct electricity through the light control film or when measurement using an optical method is difficult, the laminated glass structure may be appropriately cut out and the actual thickness of each layer may be measured using a vernier caliper to calculate the thickness difference X.

[0266] Specifically, for example, in the case of the laminated glass structure 1 obtained in Example 1, the thicknesses of the first layer film 1, the second layer PET substrate (substitute for light-control film 1), and the third layer film 1 of the laminated film excluding the glass plate were measured. Then, as shown in FIG. 3 , in the region p of the laminated glass structure 1 having the light-control film 1 (PET substrate), the thicknesses of portions p1 and p2 of the first layer (film 1) that contact both ends of the light-control film 1 in the width direction and the thickness of portion p3 of the first layer (film 1) that contacts the center of the second layer (PET substrate) in the width direction were measured. The average values ​​of the thicknesses of portions p1 and p2 were then calculated, and the difference X (absolute value) between this average value and the thickness of portion p3 was calculated. Based on this thickness difference X, the laminated glass structure was evaluated according to the following criteria. It can be said that the smaller the thickness difference, the more suppressed the occurrence of distortion and warping. A: The thickness difference X is less than 50 μm. C: The thickness difference X is 50 μm or more.

[0267] For convenience, an example where X = 0 is shown in Fig. 2. That is, Fig. 2 shows p1, p2, and p3 as being positioned approximately the same in the thickness direction (the vertical direction in Fig. 2). However, in reality, the positions of portions p1 and p3 in the thickness direction may differ from each other, and the positions of portions p2 and p3 in the thickness direction may also differ from each other, so that the thickness difference X may exceed 0 mm.

[0268]

[0269] <Evaluation Test 2> The following evaluation test was carried out using each of the laminated glass structures obtained in Examples 1 to 3 and 5 and Comparative Examples 1 and 2. The results are shown in Table 3. Table 3 also lists the types of interlayer films and functional layers constituting each laminated glass structure (glass plates are omitted).

[0270] (1) Calculation of the value (|a-b| / c) and the thickness ratio (a / b) Laminated glass assemblies corresponding to the laminated glass assemblies obtained in Examples 1 to 3 and 5 and Comparative Examples 1 and 2 were prepared (see also Figures 2 and 3). Here, since using the light control film as is would make the measurement complicated, a PET substrate was used instead of the light control film. That is, the PET substrate, which accounts for most of the thickness of light control film 1 or 2, was used as light control film 1 or 2. A PET substrate (188 μm) was used instead of light control film 2 (thickness 170 μm), and a laminate of two PET substrates (188 μm) was used instead of light control film 1 (thickness 400 μm). The planar size of the PET substrate was the same as that of light control films 1 and 2. Therefore, the layer structure of the laminated glass assemblies used in this evaluation test corresponds to the functional layer Z in Figures 2 and 3 replaced with one or two PET substrates.

[0271] Then, assuming the refractive index of each layer to be 1.5, the thickness (a) of the region of the laminated glass construct that did not have the light control film (or substitute PET substrate), the thickness (b) of the center of the region that had the light control film (or substitute PET substrate), and the thickness (c) of the light control film (or substitute PET substrate) were measured using an "OptiGauge" multilayer film thickness measuring device manufactured by Lumetrics, Inc., USA. Note that if measurement using optical methods is difficult, the laminated glass construct may be appropriately cut out and each thickness may be measured using a vernier caliper or the like.

[0272] (2) Shape Observation The shapes of the laminated glass structures obtained in Examples 1 to 3 and 5 and Comparative Examples 1 and 2 were observed by viewing them from a direction perpendicular to the thickness direction (i.e., from the side). As a result, in all of the laminated glass structures obtained in each Example and Comparative Example, the glass plates, the interlayer film, and the light control film had curved shapes with convex portions in the same direction.

[0273] (3) Crack Defect Rate Laminated glass structures were produced four times each by the method described in Examples 1 to 3 and 5 and Comparative Examples 1 and 2, and the rate of cracks in the laminated glass structures was evaluated according to the following criteria. "Crack" here means a crack of 1 cm or more in the glass sheet. C: Cracks occurred two times out of the four times. A: Cracks occurred once or did not occur out of the four times.

[0274] (4) Workability Evaluation was made according to the following criteria based on the number of members to be laminated when obtaining a laminated glass structure. For example, the laminated glass structure obtained in Example 1 has two glass plates, two films 1, and a light control film 1, for a total of five members. A: The number of laminated members was five or less. C: The number of laminated members was six or more.

[0275]

[0276] <Evaluation Test 3> The following evaluation test was carried out using each of the laminated glass structures obtained in Examples 6 and 7 and Comparative Example 3. The results are shown in Table 4. Table 4 also lists the types of interlayer films and functional layers constituting each laminated glass structure (glass plates are omitted).

[0277] (1) Color Unevenness After autoclaving, the laminate was placed on a light table and checked to see if there was any localized shading in the GHLC liquid crystal. The color unevenness was then evaluated according to the following criteria: No shading at all: A, Shading in 1-2 places: B, Shading in 3 or more places: C

[0278] (2) Appearance Evaluation After storing the laminate at room temperature and normal pressure for one week, it was checked whether bubbles had formed in the liquid crystal and whether it had become transparent without applying voltage. The number of bubbles of 1 mm or more was counted and evaluated according to the following criteria: No bubbles: A, 1 to 2 bubbles: B, 3 or more bubbles: C

[0279]

[0280] <Interlayer film for laminated glass> Preparation Example B11 (Film 11) 40 parts of plasticizer (3GO) were mixed with 100 parts of Resin 1 to obtain a resin composition. The obtained resin composition was fed to a twin-screw extruder and embossed using an embossing roll to produce a film-like Film 11 having a thickness of 760 μm. The creep compliance J(t) per layer of the obtained Film 11 at 90° C. was measured. The results are shown in Table 5.

[0281] Preparation Example B12 (Membrane 12) A film-like membrane 12 having a thickness of 760 μm was prepared in the same manner as in Preparation Example B11, except that Resin 2 was used instead of Resin 1. The creep compliance J(t) per layer of the obtained membrane 12 at 90 ° C. was measured. The results are shown in Table 5.

[0282] Preparation Example B13 (Membrane 13) A film-like membrane 13 having a thickness of 760 μm was prepared in the same manner as in Preparation Example B11, except that Resin 3 was used instead of Resin 1. The creep compliance J(t) per layer of the obtained membrane 13 at 90 ° C. was measured. The results are shown in Table 5.

[0283] Preparation Example B14 (Film 14) Film 14 having a thickness of 760 μm was prepared in the same manner as in Preparation Example B11, except for the temperature and pressure conditions during embossing. The creep compliance J(t) per layer of the obtained Film 14 at 90 ° C. was measured. The results are shown in Table 5.

[0284] Preparation Example B15 (Film 15) Film 15 having a thickness of 760 μm was prepared in the same manner as in Preparation Example B11, except for the temperature and pressure conditions during embossing. The creep compliance J(t) per layer of the obtained Film 15 at 90 ° C. was measured. The results are shown in Table 5.

[0285] <Evaluation Test 4> For each of the films obtained in Preparation Examples B11 to B15, the remaining embossing distance and surface roughness (RzJIS94 and Rc) were determined according to the methods described above. FIG. 4 is a photograph taken from above of the laminate when the remaining embossing distance of Film 11 was measured. T indicates the location where the transmittance was measured, and the transmittance was measured by sliding the transmittance meter from the T1 direction. The results are shown in Table 5.

[0286]

[0287] Test Example 1 (Laminated Glass Structure 11) Two glass plates, two films 11, and two PET substrates were prepared. One film 11, two PET substrates, and the other film 11 were stacked in this order on one glass plate, and then the other glass plate was stacked on top of that to obtain a laminate. As shown in Figures 2 and 3, the glass plate and film 11 each had a planar size of 300 mm x 300 mm, and the two PET substrates each had a planar size of 200 mm x 200 mm. They were arranged so that the centroids of the glass plate, film 11, and PET substrates overlapped in plan view. Figure 2 is a schematic side view of the layer structure of the laminate, and Figure 3 is a schematic plan view of the laminate. Here, in Figures 2 and 3, the functional layer Z is replaced with two PET substrates.

[0288] The laminate was placed in a vacuum laminator "LAMINATOR 0505S" manufactured by Nisshinbo Mechatronics Inc. and degassed for 5 minutes at 90°C and a vacuum of 4 kPa. Next, while still degassed at 90°C, a pressure of 100 kPa was applied to the laminate using a medium-speed press (pressure increase rate: 2 kPa / s), and then the laminate was held at 90°C and 100 kPa for 3 minutes. Thereafter, pressure bonding was performed for 20 minutes using an autoclave at 140°C and 1.3 MPa, thereby obtaining a laminated glass structure 11.

[0289] Test Example 2 (Laminated Glass Structure 13) A laminated glass structure 13 was obtained in the same manner as in Test Example 1, except that films 14 were used instead of the films 11 disposed on both sides of the two PET substrates.

[0290] Test Example 3 (Laminated Glass Structure 14) A laminated glass structure 14 was obtained in the same manner as in Test Example 1, except that films 15 were used instead of films 11 disposed on both sides of the two PET substrates.

[0291] Comparative Test Example 1 (Laminated Glass Structure C11) A laminated glass structure C11 was obtained in the same manner as in Test Example 1, except that instead of the films 11 arranged on both sides of the two PET substrates, films 13 were used.

[0292] Comparative Test Example 2 (Laminated Glass Structure 12) A laminated glass structure 12 was obtained in the same manner as in Test Example 1, except that films 12 were used instead of the films 11 disposed on both sides of the two PET substrates.

[0293] <Evaluation Test 5> The following evaluation test was carried out using each of the laminated glass structures obtained in Test Examples 1 to 3 and Comparative Test Examples 1 and 2. The results are shown in Table 6. Table 6 also lists the thicknesses of the interlayer film and PET substrate constituting each laminated glass structure (glass plates are omitted).

[0294] (1) Step-Conforming Ability Each laminated glass structure obtained in Test Examples 1 to 3 and Comparative Test Examples 1 and 2 was prepared (see also Figures 2 and 3). Then, assuming a refractive index of each layer to be 1.5, the thickness (a) of the region of the laminated glass structure that did not have a PET substrate and the thickness (b) of the central portion of the region that had a PET substrate were measured using an "OptiGauge" multilayer film thickness measuring device manufactured by Lumetrics, Inc., USA. If measurement using optical techniques is difficult, the laminated glass structure may be appropriately cut out and each thickness may be measured using a vernier caliper or the like. The ratio (a / b) of the thickness (a) to the thickness (b) was then calculated and evaluated according to the following criteria: A (Excellent): The ratio was 0.9 or more and 1.0 or less; B (Good): The ratio was 0.8 or more and less than 0.9; C (Bad): The ratio was less than 0.8, or cracks occurred and measurement was not possible.

[0295] Here, "the thickness (b) of the central part of the region of the laminated glass structure having the PET substrate" refers to the sum of the thicknesses of the layers at a position corresponding to the centroid of the PET substrate when the laminated glass structure is viewed in plan. Also, "the thickness (a) of the region of the laminated glass structure not having the PET substrate" refers to the sum of the thicknesses of the layers at a midpoint between an arbitrary end E1 of the PET substrate and an end E2 of the laminated glass structure that is closest to the end E in the horizontal direction when the laminated glass structure is viewed in plan.

[0296]

[0297] <Interlayer film for laminated glass> Preparation Example B21 (Film 21) 40 parts of plasticizer (3GO) were mixed with 100 parts of Resin 1 to obtain a resin composition. The obtained resin composition was fed to a twin-screw extruder and embossed using an embossing roll. A film-like film 21 with a thickness of 760 μm was produced. The obtained Film 21 was measured for its exposed film area, Tg, creep compliance J(t) at 90°C, and surface roughness (RzJIS94, Rc). The results are shown in Table 7.

[0298] Preparation example B22 (film 22) Except for using resin 2 instead of resin 1, prepare film-like film 22 with a thickness of 760 μm in the same manner as preparation example B21. For obtained film 22, measure the film exposed area, Tg, creep compliance J (t) at 90 ° C, and surface roughness (RzJIS94, Rc). Results are shown in Table 7.

[0299] Preparation example B23 (film 23) Except for using resin 3 instead of resin 1, prepare film-like film 23 with a thickness of 760 μm in the same manner as preparation example B21. For obtained film 23, measure the film exposed area, Tg, creep compliance J (t) at 90 ° C, and surface roughness (RzJIS94, Rc). Results are shown in Table 7.

[0300] <Evaluation Test 6> Using samples measuring 30 cm long x 30 cm wide cut out from each of the films obtained in Preparation Examples B21 to B23, laminated glass was produced as follows, and an impact resistance test was performed. The results are shown in Table 7.

[0301] (1) Preparation of Laminated Glass Each sample was maintained at a constant temperature of 23°C and 28% RH for 4 hours. Separately, two float glass sheets measuring 30 cm long x 30 cm wide x 3 mm thick and conforming to JIS R3202 (2011) were prepared. The glass and the sample were laminated so that the tin side of the glass contacted the sample and the sample was positioned between the two sheets of glass. The resulting laminate was pre-pressed using a heated roll at 170°C. The pre-pressed laminate was placed in an autoclave and heated to 90°C at 2°C / min. When the temperature reached 40°C during heating, the pressure was reduced to 0.1 MPa. After reaching 90°C, the sample was held for 20 minutes and cooled at 2°C / min. When the temperature reached 40°C, the pressure was returned to normal pressure. In this way, laminated glass was prepared.

[0302] (2) Impact Resistance Test Using each of the laminated glasses prepared as described above, an impact resistance test was carried out at -20°C in accordance with JIS R3212 (1998). In the impact resistance test, the presence or absence of penetration was checked, and cases where there was no penetration were rated as "A", and cases where there was penetration were rated as "B". Furthermore, when there was no penetration (rated as "A"), the size of the peeled part of the film at the part of the impact surface where the steel ball fell was measured, and the result was judged according to the following criteria: A: No peeling B: The size of the peeled part was less than 1 cm C: The size of the peeled part was 1 cm or more

[0303]

[0304] 10: Laminated glass structure 10A: Laminate used when calculating the remaining embossing distance G1, G2, G: Glass plate F1, F2, F: Interlayer film Z: Functional layer (or PET substrate)

Claims

1. A glass sheet comprising, in this order, a first interlayer film, a functional layer, a second interlayer film, and a second glass sheet, wherein the first interlayer film has a creep compliance of 6.0 x 10 at 90°C per layer. －５ Pa －１ The laminated glass structure is characterized by the above.

2. A laminated glass structure comprising, in this order: a first glass plate; a first interlayer film; a light control film; a second interlayer film; and a second glass plate; wherein the first glass plate, the first interlayer film, the light control film, the second interlayer film, and the second glass plate are all curved so as to have convex portions in the same direction; and the absolute value |a-b| of the difference between the thickness (a) of the region of the laminated glass structure that does not have the light control film and the thickness (b) of the center of the region that has the light control film, divided by the thickness (c) of the light control film, is 0.1 to 0.5 (|a-b| / c).

3. The laminated glass structure according to claim 1, wherein the functional layer is a guest-host liquid crystal (GHLC) film.

4. The creep compliance at 90°C per layer is 6.0 x 10 －５ Pa －１ Above 1.0 x 10 －３ Pa －１ The laminated glass structure according to any one of claims 1 to 3, wherein:

5. The creep compliance at 90°C per layer is 8.0 x 10 －５ Pa －１ Above 1.0 x 10 －３ Pa －１ The laminated glass structure according to any one of claims 1 to 3, wherein:

6. The laminated glass structure according to any one of claims 1 to 5, characterized in that the first interlayer film contains a polyvinyl acetal resin.

7. The laminated glass structure according to claim 6, wherein the polyvinyl acetal resin has a hydroxyl group content of 30.9 mol % or more or a weight average molecular weight of 245,000 or more.

8. The laminated glass structure according to claim 6 or 7, wherein the first interlayer film further contains a plasticizer, and the plasticizer is at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives thereof in which some of the hydrogen atoms of the terminal hydroxyl groups are substituted with alkyl groups.

9. An interlayer film for laminated glass, comprising a polyvinyl acetal resin, having at least one surface with an uneven surface, and having a residual embossing distance of less than 27 mm as calculated by the following method: <Method for calculating the residual embossing distance> Two float glass sheets measuring 300 mm long x 300 mm wide x 3 mm thick and conforming to JIS R3202 (2011) are prepared. Two interlayer films for laminated glass measuring 300 mm long x 300 mm wide x 760 μm thick and one polyethylene terephthalate (PET) film measuring 200 mm long x 200 mm wide x 188 μm thick are also prepared. The float glass sheets, interlayer film for laminated glass, PET film, interlayer film for laminated glass, and float glass sheets are then laminated in this order, with the centroids of each component aligned in a plan view. The resulting laminate (referred to as "Laminate 1") is degassed for 5 minutes at a vacuum pressure of 4 kPa. When the laminate 1 after degassing is viewed in a plane, the transmittance (referred to as transmittance B) is measured from one end of the laminate 1 to the other end opposite the end along a center line passing through the centroid of the PET film. The distance between a first portion where the ratio (B / A) of the transmittance A to the transmittance B first becomes 0.75 or less and an end of the region where the PET film is disposed that is closest to the first portion is measured, and this distance is defined as the remaining embossing distance. Transmittance A is the maximum transmittance of Laminate 3 described below. Two sheets of the same float glass sheets and interlayer film for laminated glass as those used to obtain Laminate 1 were prepared, and then the float glass sheets, interlayer film for laminated glass, interlayer film for laminated glass, and float glass sheets were laminated in this order so that the centroids of each component coincided in a plan view. This laminate (referred to as Laminate 2) was placed in a vacuum laminator "LAMINATOR 0505S" manufactured by Nisshinbo Mechatronics Inc. and degassed at a vacuum pressure of 4 kPa for 5 minutes. Next, while still degassed, a pressure of 100 kPa is applied to the laminate 2 using a medium-speed press (pressure increase rate: 2 kPa / s), and then the laminate is maintained at 100 kPa for 3 minutes. Thereafter, pressure bonding is performed for 20 minutes using an autoclave under conditions of 140°C and 1.3 MPa, thereby obtaining a laminate 3.

10. An interlayer film for laminated glass, comprising a polyvinyl acetal resin, characterized in that the exposed area of ​​the film calculated by the following method is 90% or less by area. <Method for calculating the exposed area of ​​the film> As a sample, one sheet of interlayer film for laminated glass measuring 30 cm long x 15 cm wide is prepared and maintained at constant temperatures of 23°C and 28% RH for 4 hours. Separately, two sheets of float glass measuring 30 cm long x 15 cm wide x 3 mm thick and conforming to JIS R3202 (2011) are prepared. The glass and the sample are then laminated so that the tin side of the glass contacts the sample and the sample is positioned between the two sheets of glass. The resulting laminate is pre-pressed using a heated roll at 170°C. The pre-pressed laminate is placed in an autoclave and heated to 90°C at 2°C / min. During heating, the pressure is reduced to 0.1 MPa when the temperature reaches 40°C. After reaching 90°C, the temperature is maintained for 20 minutes and then lowered at a rate of 2°C / min. When the temperature has lowered to 40°C, the pressure is returned to normal pressure. The obtained optical laminate is allowed to stand for 16 hours in an environment at a temperature of -18°C±0.6°C, and then the optical laminate, fixed at an inclination angle of 45 degrees, is struck 72 times per minute with a hammer whose spring screw is adjusted so that the impact force at the top dead center of the stroke is 10.5±0.5 kg. The impact is performed so that the hammer strikes the optical laminate horizontally. The impact is applied from the bottom of the optical laminate 13 times at 11.5 mm intervals in the horizontal direction (stroke 150 mm) and 10 times at 9 mm intervals in the vertical direction (stroke 90 mm), for a total of 130 times. After the impact, an image of the optical laminate is taken, and the exposed film area (area %) of the sample where the glass has peeled off from the optical laminate and is exposed is analyzed.

11. The interlayer film for laminated glass according to claim 10, wherein at least one surface has an uneven shape.

12. The interlayer film for laminated glass according to any one of claims 9 to 11, further comprising a plasticizer, wherein the plasticizer is at least one selected from the group consisting of triethylene glycol-di-2-ethylhexanoate, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glyceryl ether, polyoxypropylene diglyceryl ether, and derivatives of these compounds in which some of the hydrogen atoms of their terminal hydroxyl groups have been substituted with alkyl groups.

13. The creep compliance at 90°C per layer is 6.0 x 10 －５ Pa －１ Above 1.0 x 10 －３ Pa －１ The interlayer film for laminated glass according to any one of claims 9 to 12, wherein:

14. The interlayer film for laminated glass according to any one of claims 9 to 13, characterized in that the polyvinyl acetal resin has a hydroxyl group content of 30.9 mol% or more, or a weight average molecular weight of 245,000 or more and 280,000 or less.

15. A laminated film having a structure in which the interlayer film for laminated glass according to any one of claims 9 to 14 and a functional layer are laminated, wherein the functional layer is at least one material selected from the group consisting of a light control film, a display element film, and a solar cell element.

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