JP2018138503A - Interlayer film for glass laminate, and glass laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interlayer film for glass laminate that makes it possible to form a glass laminate having excellent heat insulation performance as well as excellent breaking resistance, and a glass laminate using the interlayer film for glass laminate.SOLUTION: Disclosed is an interlayer film for glass laminate 10 that contains a curable resin composition containing an acrylic polymer, and a hollow silica particle 51. The hollow silica particle 51 has a porosity of 40% or more and 80% or less. The interlayer film for glass laminate 10 may be a multilayer film that has a first layer 2 containing the hollow silica particle 51, and a second layer 3 provided on its one principal face side and containing the curable resin composition.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminated glass applicable to uses such as automobiles and buildings, and an interlayer film for laminated glass that can be used to form the laminated glass.

  Laminated glass is excellent in safety because it has less scattering of glass fragments even if it is damaged by external impact. For this reason, laminated glass is widely used in automobiles, railway vehicles, aircraft, ships, buildings, and the like. Laminated glass is generally manufactured by sandwiching an intermediate film between a pair of glass plates. Patent Document 1 and Patent Document 2 disclose examples of interlayer films for laminated glass.

JP 2001-039741 A International Publication No. 2012/063881

  In recent years, a shift from a fuel vehicle using an internal combustion engine to an electric vehicle using an electric motor has been studied. Compared to a fuel vehicle using an internal combustion engine, an electric vehicle using an electric motor has a problem that the distance that can be traveled by one charge is short. Furthermore, when the air conditioning apparatus is operated during traveling, there is a problem that the distance that can be traveled by one charge is remarkably reduced.

  In order to increase the operating efficiency of the air conditioner, it is desirable that the laminated glass used in the electric vehicle has high heat insulation properties. For example, laminated glass that can prevent external heat from flowing into the vehicle in a high-temperature environment and prevent internal heat from flowing out of the vehicle in a low-temperature environment is intended to increase the operating efficiency of the air conditioner. It is valid. In addition, the laminated glass is also required to have an equal or higher splitting property than a glass having an equivalent thickness.

  However, in the laminated glass using the conventional interlayer film as described in Patent Document 1, the heat insulation is not sufficient, and there is room for improvement in terms of splitting resistance. On the other hand, a laminated glass using an interlayer film as described in Patent Document 2 has a certain degree of heat insulation, but is not necessarily sufficient in terms of splitting properties.

  An object of one aspect of the present invention is to provide an interlayer film for laminated glass capable of forming a laminated glass having excellent properties in terms of heat insulation in addition to excellent splitting properties, and an interlayer film for laminated glass It is in providing the laminated glass used.

  One aspect of the present invention provides an interlayer film for laminated glass containing a curable resin composition containing an acrylic polymer and hollow silica particles. The hollow silica particles have a porosity of 40% or more and 80% or less. The interlayer film for laminated glass is a single-layer film in which the hollow silica particles are distributed throughout the interlayer film for laminated glass, or the first layer containing the hollow silica particles and one of the main layers thereof. It is a multilayer film | membrane which has a 2nd layer provided in the surface side and containing the said curable resin composition.

  When the interlayer film for laminated glass is a multilayer film having the first layer containing the hollow silica particles and the second layer containing the curable resin composition provided on one main surface side thereof, The second layer may be stacked in contact with the first layer.

  The laminated glass may further have a third layer provided on the other main surface side of the first layer and containing the curable resin composition. In this case, the third layer may be stacked in contact with the first layer.

  When the thickness of the interlayer film for laminated glass is T (μm), the thickness of the first layer may be 0.005T or more and 0.6T or less.

  Acrylic polymer is an acrylic monomer having a (meth) acryloyl group, a siloxane compound having an ethylenically unsaturated group, an ethylenically unsaturated group equivalent of 2000 to 20000 g / mol, and a compound different from the acrylic monomer. And as a monomer unit.

  The acrylic polymer may have a weight average molecular weight of 100,000 or more. The acrylic polymer may have a glass transition temperature of −10 ° C. or lower.

The content of the hollow silica particles may be 0.1 g / m ² or more and 80 g / m ² or less based on the area of the main surface of the glass interlayer film.

  Another aspect of the present invention provides a laminated glass comprising two opposing glass plates and an intermediate film sandwiched between the two glass plates. The intermediate film is the glass intermediate film, and the cured resin composition is cured.

  According to one aspect of the present invention, an interlayer film for laminated glass that can form a laminated glass having excellent properties in terms of heat insulation in addition to excellent splitting properties, and an interlayer film for laminated glass The laminated glass used is provided.

It is sectional drawing which shows one Embodiment of the intermediate film for laminated glasses. It is sectional drawing which shows one Embodiment of a laminated glass. It is sectional drawing which shows one Embodiment of a hollow silica particle. It is sectional drawing which shows one Embodiment of the intermediate film for laminated glass of a single layer. It is sectional drawing which shows one Embodiment of the film material which has an intermediate film. It is sectional drawing which shows one Embodiment of a laminated glass. It is a schematic diagram which shows the method of evaluating the splitting property of a laminated glass.

  Hereinafter, some embodiments of the present invention will be described in detail with reference to the drawings as necessary. However, the present invention is not limited to the following embodiments.

  FIG. 1 is a cross-sectional view schematically showing one embodiment of an interlayer film for laminated glass. An intermediate film 10 shown in FIG. 1 is a multilayer intermediate film having a laminated structure of two or more layers. The interlayer film 10 is an interlayer film for laminated glass that is used to obtain a laminated glass. The intermediate film 10 includes a first layer 2, a second layer 3 disposed on the first main surface 2 a side of the first layer 2, and a first main surface 2 a of the first layer 2. And a third layer 4 disposed on the opposite second main surface 2b side. The second layer 3 is laminated in contact with the first main surface 2 a of the first layer 2. The third layer 4 is laminated in contact with the second major surface 2b of the first layer 2. The first layer 2 is a layer located at an intermediate portion in the thickness direction of the intermediate film 10 and mainly functions as a layer that enhances heat insulation. The 2nd layer 3 and the 3rd layer 4 are layers which are located in the outermost layer of the intermediate film 1, function as a protective layer and an adhesive layer, and can have adhesiveness. The first layer 2 is disposed between the second layer 3 and the third layer 4. That is, the intermediate film 1 has a multilayer structure in which the second layer 3, the first layer 2, and the third layer 4 are laminated in this order. Although the 3rd layer 4 does not need to be provided, the penetration resistance (split resistance) of a laminated glass is further improved by providing the 2nd layer 3 and the 3rd layer 4. Can do. Furthermore, by providing the second layer 3 and the third layer 4, the handleability of the intermediate film 10 is improved.

  Other layers may be provided between the first layer 2 and the second layer 3 and between the first layer 2 and the third layer 4, respectively. Examples of the other layer include a layer containing a thermoplastic resin such as polyvinyl acetal resin and polyethylene terephthalate. Each of the first layer 2 and the second layer 3 and the first layer 2 and the third layer 4 may be directly laminated. In this case, the boundary between the first layer 2 and the second 3 or the third layer may be unclear as a result of integration of the curable resin compositions described later.

  FIG. 2 is a cross-sectional view showing an embodiment of a laminated glass obtained using the interlayer film 10 for laminated glass according to the embodiment of FIG. A laminated glass 30 shown in FIG. 2 includes two opposing glass plates 21 and 22 and an intermediate film 10 sandwiched between the two glass plates 21 and 22. One glass plate 21 is laminated on the main surface 3a (the first main surface 1a of the intermediate film) opposite to the first layer 2 of the second layer 3, and the first layer 3 of the third layer 4 is A glass plate 22 is laminated on the main surface 4a opposite to the layer 2 (the other main surface 1b of the intermediate film).

  The first layer 2 includes a plurality of hollow silica particles 51 and the resin composition 5. FIG. 3 is a cross-sectional view showing an embodiment of hollow silica particles that can be included in the first layer 2. A hollow silica particle 51 shown in FIG. 3 has a substantially cubic outer shell portion 53 forming a hollow portion 52. However, the shape of the hollow silica particles is not limited to this, and may be spherical, for example. The hollow portion 52 is a space surrounded by the outer shell portion 53. The porosity of the hollow silica particles 51 may be 40% or more and 80% or less. Such an interlayer film containing hollow silica particles can enhance the heat insulation of the laminated glass. When the porosity of the hollow silica particles is 40% or more, the outer shell portion of the hollow silica particles is sufficiently thin, so that a highly transparent laminated glass can be obtained. Furthermore, even if the thickness of the first layer is thin, the heat insulating property can be improved, so that a decrease in the transparency of the laminated glass due to the use of hollow silica particles is suppressed, and a laminated glass having sufficiently high transparency is obtained. Can do.

  In the case of a multilayer interlayer film for laminated glass having a laminated structure of two or more layers as shown in FIG. 1, the hollow silica particles can be easily and partially present in the interlayer film. For example, the thickness of the first layer 2 can be reduced to partially increase the density of the hollow silica particles in the laminated glass interlayer film. On the other hand, even if the thickness of the first layer 2 is reduced, the penetration resistance of the laminated glass can be increased by increasing the thicknesses of the second layer 3 and the third layer 4. For example, when the thickness of the intermediate film 10 is T (μm), the thickness of the first layer 2 may be 0.005T or more and 0.6T or less. The thickness T of the intermediate film 10 may be 0.010 to 2.0 μm.

  The porosity of the hollow silica particles 51 is preferably 45% or more, more preferably 50% or more, and further preferably 55% or more. When the porosity of the hollow silica particles is equal to or higher than these lower limits, the heat insulating property of the laminated glass is further enhanced. The porosity of the hollow silica particles 51 is preferably 75% or less, more preferably 70% or less, and even more preferably 65% or less. When the void ratio of the hollow silica particles 51 is less than or equal to these upper limits, the strength of the hollow silica particles 51 is further increased, so that the outer shell portion is hardly cracked.

The porosity of the hollow silica particles 51 is defined as the volume ratio (volume%) of the hollow portion 52 to the total volume of the hollow portion 52 and the outer shell portion 53. In the case of the substantially cubic hollow silica particles 51 as shown in FIG. 3, the value calculated by the following formula from the outer diameter and inner diameter of the outer shell portion 53 can be regarded as the porosity.
Porosity (volume%) = (inner diameter ³ / outer diameter ³ ) × 100
Here, the outer diameter means the length of one side of the cube when the outer surface of the outer shell portion 53 is approximated to a cube. The inner diameter means the length of one side of the cube when the inner surface of the outer shell 53 is approximated to a cube. The outer diameter and the outer diameter can be obtained by measuring the outer diameter and inner diameter of the outer shell portion of any 50 hollow silica particles using a transmission electron microscope and arithmetically averaging them.

  The outer diameter of the outer shell portion 53 of the hollow silica particle 51 is not particularly limited. The outer diameter of the outer shell portion 53 of the hollow silica particle 51 is preferably 30 nm or more, more preferably 40 nm or more, and still more preferably 50 nm or more. When the outer diameter is not less than these lower limits, the production of the hollow silica particles 51 is easy. The outer diameter of the outer shell portion 53 of the hollow silica particle 51 is preferably 300 nm or less, more preferably 200 nm or less, and even more preferably 150 nm or less. When the outer diameter of the hollow silica particles 51 is less than or equal to these upper limits, the heat insulating property of the laminated glass is further enhanced.

  The inner diameter of the outer shell portion 53 of the hollow silica particle 51 is not particularly limited. The inner diameter of the outer shell portion 53 of the hollow silica particle 51 is preferably 10 nm or more, more preferably 20 nm or more, and further preferably 30 nm or more. When the inner diameter is equal to or greater than these lower limits, the production of the hollow silica particles 51 is easy. The inner diameter of the outer shell portion 53 of the hollow silica particle 51 is preferably 200 nm or less, more preferably 150 nm or less, and still more preferably 100 nm or less. When the inner diameter is not more than these upper limits, the heat insulating property of the laminated glass is further enhanced.

  The outer shell portion 53 may form a plurality of holes. The hole diameter may be 2 nm or less. The hole may be, for example, a through hole that penetrates the outer shell 53 from the inner surface to the outer surface. In the above-described calculation of the porosity, the volume of the hole in the outer shell portion is not included in the volume of the hollow portion.

The density of the outer shell portion 53 is not particularly limited. The density of the shell portion 53 is preferably 0.5 g / cm ³ or more, 1.9 g / cm ³ or less, more preferably 0.7 g / cm ³ or more, 1.7 g / cm ³ or less, more preferably 0. It is 9 g / cm ³ or more and 1.5 g / cm ³ or less. When the density of the outer shell portion 53 is not less than the lower limit and not more than the upper limit, the heat insulating property of the laminated glass is further enhanced.

  The content of the hollow silica particles 51 contained in the first layer 2 is not particularly limited. In 100% by mass of the first layer, the content of the hollow silica particles is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 7% by mass or more. When the content of the hollow silica particles 51 is equal to or higher than these lower limits, the heat insulating property of the laminated glass is further enhanced. The content of the hollow silica particles 51 is preferably 50% by mass or less, more preferably 40% by mass or less, still more preferably 20% by mass or less, particularly preferably 10% by mass or less, and most preferably 8% by mass or less. When the content of the hollow silica particles 51 is less than or equal to these upper limits, the transparency of the laminated glass is increased.

In the intermediate film 10 or the first layer 2, the content of the hollow silica particles 51 is preferably 0.1 g / m ² or more and 0.2 g / m ^{2 based on} the area of the first main surface 1 a of the intermediate film 10. m ² or more, 0.5 g / m ² or more, or 1 g / m ² or more. When the content of the hollow silica particles 51 is equal to or higher than these lower limits, the heat insulating property of the laminated glass is further enhanced. The content of the hollow silica particles 51 is preferably 80 g / m ² or less, 70 g / m ² or less, 10 g / m ² or less, or 8 g / m ^{2 based on} the area of the first main surface 1a of the intermediate film 10. It is as follows. When the content of the hollow silica particles 51 is less than or equal to these upper limits, the transparency of the laminated glass is increased.

  By adjusting the content of hollow silica particles (mass% × 0.01) in the first layer and the thickness (μm) of the first layer, the present inventors have further improved heat insulation. It has been found that an interlayer film for laminated glass is obtained. In order to obtain an interlayer film for laminated glass having even better heat insulation, the content of hollow silica particles in the first layer (mass% × 0.01) and the thickness of the first layer (μm) The product is preferably 0.1 or more and 60 or less. When this product is within the range of these upper and lower limits, the heat insulating property of the laminated glass is further enhanced. The more preferable lower limit of the product is 0.2, the still more preferable lower limit is 0.3, and the particularly preferable lower limit is 0.4. The more preferable upper limit of the product is 54, the still more preferable upper limit is 48, and the particularly preferable upper limit is 42.

  The method for producing the hollow silica particles is not particularly limited. An example of a method for producing hollow silica particles is shown below.

  Grows crystals of calcium carbonate particles as cores. The crystals of calcium carbonate particles are calcite and hexagonal, but by controlling the synthesis conditions, it is possible to grow calcium carbonate crystals having a cubic shape.

  Next, for example, after growing the crystal so that the outer diameter of the calcium carbonate particles is 10 to 180 nm, it is dehydrated through a ripening step, and a hydrous calcium carbonate particle slurry containing 70 mass% or more of calcium carbonate particles is obtained. obtain.

  A dispersion obtained by dispersing the hydrous calcium carbonate particle slurry in ethanol is mixed with silicon alkoxide and ammonia, and the surface of the calcium carbonate particles is coated with silica (silicon dioxide) by a sol-gel method. The calcium carbonate particles coated with silica are washed and then dispersed in water to obtain a dispersion. By adding hydrochloric acid to the dispersion and dissolving the calcium carbonate particles, hollow silica particles having an outer shell portion having an outflow hole from which calcium carbonate has flowed out can be obtained. Furthermore, by heating the hollow silica particles to 200 to 800 ° C., the outflow holes can be blocked. Although it is not necessary to block all outflow holes, it is preferable that no pores having a pore diameter exceeding 2 nm exist in the outer shell portion of the hollow silica particles.

  The method for producing hollow silica particles includes a first step of growing calcium carbonate particle crystals, a second step of coating the surface of the calcium carbonate particles with silica (silicon dioxide), and dissolving the calcium carbonate particles. The third step of forming the hollow silica particles having the outer shell part forming the hollow part and the fourth step of heating the hollow silica particles may be provided. By using such a production method, hollow silica particles having low thermal conductivity and high heat insulation can be obtained.

  In the first step, for example, calcium carbonate particles having a primary particle diameter of 20 to 200 nm measured by a transmission electron microscope are dispersed in water and aged to have a particle diameter of 20 to 700 nm determined by a static light scattering method. It may include.

  In the second step, for example, the aged calcium carbonate particles are dehydrated to form a water-containing cake, the water-containing cake and alcohol are mixed, and the mixture is further mixed with aqueous ammonia, water, and silicon alkoxide. And coating the surface of the calcium carbonate particles with silica may be included.

  The volume ratio of silicon alkoxide to alcohol (volume of silicon alkoxide / volume of alcohol) is preferably 0.002 or more and 0.1 or less. The amount of ammonia contained in the aqueous ammonia is preferably 4 mol or more and 15 mol or less with respect to 1 mol of silicon alkoxide. The blending amount of water is preferably 25 mol or more and 200 mol or less with respect to 1 mol of silicon alkoxide.

  In the third step, for example, calcium carbonate particles coated with silica and water are mixed, and an acid is further added thereto to make the acid concentration 0.1 to 3 mol / L, whereby calcium carbonate particles It may include forming hollow silica particles in which a hollow portion is formed by dissolving.

  The fourth step may include, for example, heating the hollow silica particles to 200 to 800 ° C.

  The surface of the hollow silica particles may be treated with a surface modifier or coated with a surface modifier. Examples of surface modifiers include compounds having an isocyanate group such as triethoxypropyl isocyanate silane and isocyanate, compounds having an isocyanurate group, compounds having an alkyl group such as triethoxybutyl silane, and vinyl groups such as triethoxypropyl vinyl silane. And compounds having an acryloxy group such as triethoxypropylacryloxysilane. By using the surface modifier, the dispersibility of the hollow silica particles in the first layer can be enhanced.

  The resin composition 5 constituting the first layer 2 may contain an acrylic polymer similar to the curable resin composition described later contained in the second layer 3 and the third layer 4. However, the first layer 2 may not have curability. The resin composition 5 is preferably a binder resin. The resin composition 5 may contain polyethylene terephthalate.

  Each of the second layer 3 and the third layer 4 is a layer made of a curable resin composition containing an acrylic polymer, and usually contains substantially no hollow silica particles. The configuration of the curable resin composition may be the same or different between the second layer 3 and the third layer 4.

(Acrylic polymer)
The acrylic polymer is a homopolymer of an acrylic monomer having a (meth) acryloyl group in the molecule, or a copolymer containing an acrylic monomer as a monomer unit.

  The acrylic monomer constituting the acrylic polymer is usually a monofunctional monomer having one (meth) acryloyloxy group. Specific examples include (meth) acrylic acid; (meth) acrylic amide; (meth) acryloylmorpholine; methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate , Tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) ) Acrylate, dodecyl (meth) acrylate (n-lauryl (meth) acrylate), isomyristyl (meth) acrylate, stearyl (meth) acrylate, isostearyl acrylate and the like having an alkyl group having 1 to 18 carbon atoms. Kill (meth) acrylate; glycidyl (meth) acrylate; alkenyl (meth) acrylate having an alkenyl group having 2 to 18 carbon atoms such as 3-butenyl (meth) acrylate; benzyl (meth) acrylate and phenoxyethyl (meth) acrylate (Meth) acrylates having aromatic rings such as: methoxytetraethylene glycol (meth) acrylate, methoxyhexaethylene glycol (meth) acrylate, methoxyoctaethylene glycol (meth) acrylate, methoxynonaethylene glycol (meth) acrylate, methoxypolyethylene glycol (Meth) acrylate, methoxyheptapropylene glycol (meth) acrylate, ethoxytetraethylene glycol (meth) acrylate, butoxyethylene Alkali polyalkylene glycol (meth) acrylates such as recall (meth) acrylate and butoxydiethylene glycol (meth) acrylate; alicyclic groups such as cyclohexyl (meth) acrylate, isobornyl (meth) acrylate and dicyclopentanyl (meth) acrylate (Meth) acrylate having; (meth) acrylate having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate; tetrahydrofurfuryl (meth) acrylate; N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-isopropyl ( (Meth) acrylamide derivatives such as (meth) acrylamide, N, N-diethyl (meth) acrylamide and N-hydroxyethyl (meth) acrylamide; 2- (2-methacryloyloxyethyloxy) ethyl isocyanate and 2- (meth) acryloyloxy (Meth) acrylate having an isocyanate group such as ethyl isocyanate; tetraethylene glycol mono (meth) acrylate, hexaethylene glycol mono (meth) acrylate, octapropylene glycol mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, tri Polyalkylene glycol mono (meth) acrylates such as propylene glycol mono (meth) acrylate and octapropylene glycol mono (meth) acrylate; And (meth) acrylate having a hexane skeleton. These compounds can be used alone or in combination of two or more.

  The acrylic polymer is a modified acrylic having a main chain containing an acrylic monomer as a monomer unit, a urethane bond bonded to the main chain, and a (meth) acryloyloxy group bonded to the main chain via the urethane bond. Polymers can be included. The modified acrylic polymer can be produced by reacting an acrylic polymer having a hydroxyl group in the side chain with isocyanate. The acrylic polymer having a hydroxyl group in the side chain may contain, for example, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, and 6-hydroxyhexyl acrylate as monomer units. When the acrylic polymer has a (meth) acryloyl group bonded to the main chain via a urethane bond in the side chain, the acrylic polymer in the resin composition can have a higher molecular weight. The molecules of the high molecular weight acrylic polymer can be intertwined more complicatedly.

  The acrylic polymer may contain a compound copolymerizable with an acrylic monomer as a copolymerizable monomer. Examples of the compound copolymerizable with the acrylic monomer include styrene, 4-methylstyrene, vinylpyridine, vinylpyrrolidone, vinyl acetate, cyclohexylmaleimide, phenylmaleimide and maleic anhydride.

  The acrylic polymer may be provided with polymerization reactivity by introducing a (meth) acryloyl group. When the (meth) acrylic polymer has a (meth) acryloyl group, the cured product of the resin composition formed by crosslinking the acrylic polymer can be further toughened.

  The acrylic polymer may be a copolymer having an ethylenically unsaturated group and a siloxane compound which is a compound different from the acrylic monomer as a monomer unit. The siloxane compound may have an ethylenically unsaturated group equivalent of 2000 to 20000 g / mol.

  By including a cross-linking agent that cross-links the acrylic polymer, curability can be imparted to the curable resin composition. In this case, a crosslinked structure is formed by the reaction between the acrylic polymer and the crosslinking agent, whereby the curable resin composition is cured. For example, when the acrylic polymer has a hydroxyl group, a compound having two or more functional groups that react with the hydroxyl group can be used as a crosslinking agent. Polyisocyanate is mentioned as a crosslinking agent which reacts with a hydroxyl group.

  The acrylic polymer may have a weight average molecular weight of 100,000 or more. Thereby, the obtained intermediate film can be toughened, and the effect of improving reliability such as foam resistance, light resistance, and heat resistance can be obtained. From the same viewpoint, the weight average molecular weight of the acrylic polymer may be 310,000 or more, or 1 million or less. When the weight average molecular weight is larger than 1,000,000, the handling property is lowered, and there is a possibility that appearance defects such as coating streaks appear at the time of film formation. The weight average molecular weight here means a standard polystyrene equivalent value measured by gel permeation chromatography (GPC).

  The glass transition temperature of the acrylic polymer may be −10 ° C. or lower. Thereby, the effect that the impact strength of a laminated glass becomes high is acquired. The impact strength of the laminated glass mentioned here is impact strength in the sense that the glass plate on the surface is difficult to break. From the same viewpoint, the glass transition temperature of the acrylic polymer may be −100 ° C. or higher, and may be −15 ° C. or lower. The glass transition temperature (Tg) here means a value obtained by differential scanning calorimetry (temperature increase rate: 5 ° C./min) or a calculated value calculated from the composition of the copolymerization monomer.

  The second layer and the third layer may further contain a curable resin in addition to the acrylic polymer. Examples of the thermosetting resin include acrylic resins, acrylic urethane resins, and urethane resins. Furthermore, when the second layer and the third layer contain a curable resin, these layers preferably contain a curing agent for the curable resin.

(Other additives)
The curable resin composition constituting the second layer 3 and the third layer 4 may contain various additives as necessary. Examples of various additives include polymerization inhibitors, antioxidants, light stabilizers, silane coupling agents, surfactants, leveling agents, and inorganic fillers.

The polymerization inhibitor is added for the purpose of enhancing the storage stability of the curable resin composition, and examples thereof include paramethoxyphenol.
Antioxidants are added for the purpose of enhancing the heat-resistant colorability of the cured product of the curable resin composition, and examples thereof include phosphorus-based such as triphenyl phosphite; phenol-based; thiol-based antioxidants.
The light stabilizer is added for the purpose of increasing resistance to active energy rays such as ultraviolet rays, and examples thereof include HALS (Hindered Amine Light Stabilizer).
The silane coupling agent is added to improve adhesion to glass or the like, and methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-amino Examples include propyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and γ-glycidoxypropylmethyldiisopropenoxysilane.
The surfactant is added to control the peelability, and examples thereof include polydimethylsiloxane compounds and fluorine compounds.
The leveling agent is added to impart flatness of the resin composition, and examples thereof include a compound that lowers the surface tension of silicon and fluorine.

  These additives may be used alone, or a plurality of additives may be used in combination. In addition, content in the case of using these additives is small compared with an acrylic polymer normally, and is generally about 0.01-5 mass% with respect to the whole quantity of curable resin composition.

  The curable resin composition of this embodiment may contain an inorganic filler other than the hollow silica particles. Examples thereof include crushed silica, fused silica, mica, clay mineral, short glass fiber or fine powder and hollow glass, calcium carbonate, quartz powder, metal hydrate and the like. The content of the inorganic filler is preferably 0.01 to 100 parts by mass, more preferably 0.05 to 50 parts by mass with respect to 100 parts by mass of the curable resin composition based on the total solid content. 30 parts by mass is more preferable. When the content of the inorganic filler is 0.01 to 100 parts by mass, sufficient low shrinkability, improvement in mechanical strength, low thermal expansion coefficient, and the like can be obtained. The filler may be treated with a commercially available surface treatment agent such as a coupling agent, a three-roller, a bead mill, or a nanomizer to improve the dispersibility of the inorganic filler.

  The multilayer intermediate film 10 can be manufactured, for example, by forming the first layer 2, the second layer 3, and the third layer 4 and laminating them.

  FIG. 4 is a cross-sectional view schematically showing another embodiment of the interlayer film for laminated glass. The interlayer film 11 for laminated glass shown in FIG. 4 is a single-layer film composed of the resin layer 5 and the first layer 2 containing hollow silica particles dispersed throughout the resin composition 5. The hollow silica particles 51 can be the same as those according to the above-described embodiment. The resin composition 5 may be a curable resin composition having the same configuration as the curable resin composition of the second layer or the third layer according to the above-described embodiment. The hollow silica particles may be uniformly distributed in the intermediate film 11 or may be unevenly distributed in a specific region. For example, the hollow silica particles may be present more densely on one main surface of the intermediate film and the vicinity thereof than on the other main surface of the intermediate film and the vicinity thereof. The content of the hollow silica particles in the first layer (intermediate film) in the single-layer interlayer film may be in the same range as the content in the multilayer interlayer film described above.

  One of the main features of the present embodiment is that the hollow silica particle 51 having the hollow portion 52 and the outer shell portion 53 and having a porosity of 40 to 80% is used as the first layer 2 or the intermediate film. Is to include. Thereby, the heat insulation property of the laminated glass using the intermediate film can be enhanced considerably effectively.

  In recent years, there has been a shift from fuel vehicles using an internal combustion engine to electric vehicles using an electric motor and hybrid electric vehicles using an internal combustion engine and an electric motor. In an automobile using an electric motor, there is a problem that a distance that can be traveled by one charge is short. Furthermore, when the air conditioning apparatus is operated during traveling, there is a problem that the distance that can be traveled by one charge is remarkably reduced.

  In order to increase the operating efficiency of the air conditioner, it is desirable that the heat insulation of the laminated glass used in the electric vehicle is high. For example, laminated glass that can prevent external heat from flowing into the vehicle in a high-temperature environment and prevent internal heat from flowing out of the vehicle in a low-temperature environment is intended to increase the operating efficiency of the air conditioner. It is valid.

  By using the laminated glass using the interlayer film according to the present embodiment, the heat insulation can be effectively enhanced. For this reason, in the motor vehicle using an electric motor, the electric power consumed for use of an air conditioning apparatus can be reduced, and the distance which can be drive | worked by one charge in the motor vehicle using an electric motor can be lengthened.

  Therefore, the interlayer film according to the present embodiment greatly contributes to the transition from a fuel vehicle using an internal combustion engine to an electric vehicle using an electric motor and a hybrid electric vehicle using an internal combustion engine and an electric motor. In addition, the interlayer film according to the present embodiment reduces the amount of petroleum fuel used and greatly contributes to the reduction of the environmental load.

  Even in laminated glass used for buildings, high heat insulation is required in order to increase the efficiency of air conditioning. The interlayer film according to this embodiment is also useful for laminated glass used in buildings.

<Film material having an interlayer film for laminated glass>
FIG. 5 is a cross-sectional view showing an embodiment of a film material having an intermediate film. The film material 12 shown in FIG. 5 is laminated on the intermediate film 11 composed of the first layer 2, the heavy release separator 120 laminated on one main surface of the intermediate film 11, and the other main surface of the intermediate film. The light release separator 110 is provided.

  The intermediate film 11 can be obtained by processing the resin composition for an intermediate film into a sheet or film by a usual method. For example, a resin composition for an interlayer film is diluted with a ketone solvent such as 2-butanone or cyclohexanone to prepare a coating solution, and then the coating solution is flow-coated on the light release separator 110 or the heavy release separator 120. Can be processed into a sheet or film having an arbitrary film thickness by coating by a method, a roll coating method, a gravure roll method, a wire bar method, a lip die coating method, etc., and then removing the solvent from the coating film . In preparing the coating liquid, each component may be blended and then diluted with a solvent, or may be diluted with a solvent in advance before blending each component.

  From the viewpoint of coating properties, the solid content concentration of the coating solution is preferably 30% by mass or more, and more preferably 40% by mass or more. From the same viewpoint, the solid content concentration of the coating liquid is preferably 70% by mass or less, and more preferably 60% by mass or less. Further, from the above viewpoint, the viscosity of the coating liquid is preferably 1 Pa · s or more and preferably 5 Pa · s or more at the coating temperature. From the same viewpoint, the viscosity of the coating liquid is preferably 30 Pa · s or less, more preferably 25 Pa · s or less, and further preferably 15 Pa · s or less.

  In order to control the peelability between the intermediate film 11, the heavy release separator 120 and the light release separator 110, the resin composition for the intermediate film is made of a surfactant such as a polydimethylsiloxane surfactant or a fluorine surfactant. It may contain.

  The light transmittance of the intermediate film 11 with respect to light in the visible light region (wavelength: 380 nm to 780 nm) is preferably 80% or more, more preferably 90% or more, and still more preferably 95% or more. .

  As the heavy release separator 120, for example, a polymer film such as polyethylene terephthalate, polypropylene, polyethylene, and polyester is preferable, and among them, a polyethylene terephthalate film (hereinafter sometimes referred to as “PET film”) is more preferable. From the viewpoint of workability, the thickness of the heavy release separator 120 is preferably 50 to 200 μm, more preferably 60 to 150 μm, and still more preferably 70 to 130 μm. It is preferable that the planar shape of the heavy release separator 120 is larger than the planar shape of the intermediate film 11, and the outer edge of the heavy release separator 120 projects outward from the outer edge of the intermediate film 11. The width at which the outer edge of the heavy release separator 120 protrudes from the outer edge of the intermediate film 11 is preferably 2 to 20 mm from the viewpoint of ease of handling, ease of peeling, and reduction of adhesion of dust and the like. It is more preferable that When the planar shape of the intermediate film 11 and the heavy release separator 120 is a substantially rectangular shape such as a substantially rectangular shape, the width at which the outer edge of the heavy release separator 120 projects beyond the outer edge of the intermediate film 11 is 2 at least on one side. Is preferably 20 mm, more preferably 4 to 10 mm on at least one side, further preferably 2 to 20 mm on all sides, and particularly preferably 4 to 10 mm on all sides. .

  As the light release separator 110, for example, a polymer film such as polyethylene terephthalate, polypropylene, polyethylene, and polyester is preferable, and among them, a polyethylene terephthalate film is more preferable. From the viewpoint of workability, the thickness of the light release separator 110 is preferably 25 to 150 μm, more preferably 30 to 100 μm, and still more preferably 40 to 75 μm. It is preferable that the planar shape of the light release separator 110 is larger than the planar shape of the intermediate film 11, and the outer edge of the light release separator 110 projects outward from the outer edge of the intermediate film 11. The width at which the outer edge of the light release separator 110 protrudes from the outer edge of the intermediate film 11 is preferably 2 to 20 mm from the viewpoint of ease of handling, ease of peeling, and reduction of adhesion of dust and the like. It is more preferable that When the planar shape of the intermediate film 11 and the light release separator 110 is a substantially rectangular shape such as a substantially rectangular shape, the width at which the outer edge of the light release separator 110 projects beyond the outer edge of the intermediate film 11 is 2 at least on one side. Is preferably 20 mm, more preferably 4 to 10 mm on at least one side, further preferably 2 to 20 mm on all sides, and particularly preferably 4 to 10 mm on all sides. .

  The peel strength between the light release separator 110 and the intermediate film 11 is preferably lower than the peel strength between the heavy release separator 120 and the intermediate film 11. Thereby, the heavy release separator 120 is less likely to peel from the intermediate film 11 than the light release separator 110. The peel strength between the heavy release separator 120 and the intermediate film 11 and between the light release separator 110 and the intermediate film 11 can be adjusted, for example, by subjecting the heavy release separator 120 and the light release separator 110 to surface treatment. Examples of the surface treatment method include a mold release treatment with a silicone compound or a fluorine compound.

  FIG. 6 is a cross-sectional view showing an embodiment of a laminated glass obtained using the single-layer laminated glass interlayer film 11 according to the embodiment of FIG. A laminated glass 31 shown in FIG. 6 includes two glass plates 21 and 22 facing each other and an intermediate film 10 sandwiched between the two glass plates 21 and 22.

  Examples of the glass plates 21 and 22 include float glass, air-cooled tempered glass, chemically tempered glass, and multilayer glass. The glass plates 21 and 22 may be transparent plastic plates such as polycarbonate plates. The intermediate film of this embodiment can also be combined with a functional layer having functionality such as an antireflection layer, an antifouling layer, a dye layer, and a hard coat layer, a transparent protective plate, and the like.

(Antireflection layer)
The antireflection layer may be a layer having antireflection properties such that the visible light reflectance is 5% or less. As the antireflection layer, a layer obtained by treating a transparent substrate such as a transparent plastic film with a known antireflection method can be used.
(Anti-fouling layer)
The antifouling layer is for preventing the surface from becoming dirty. As the antifouling layer, a known layer composed of a fluorine resin or a silicone resin for lowering the surface tension can be used.
(Dye layer)
The dye layer is used to increase color purity. The dye layer is used to reduce unnecessary wavelength light transmitted through the laminated glass. The dye layer can be obtained by dissolving a dye that absorbs light having an unnecessary wavelength in a resin and forming or laminating it on a base film such as a polyethylene film or a polyester film.
(Hard coat layer)
The hard coat layer is used to increase the surface hardness. As a hard-coat layer, what formed or laminated | stacked acrylic resin, such as urethane acrylate and an epoxy acrylate; base films, such as a polyethylene film, can be used, for example. Similarly, in order to increase the surface hardness, a hard coat layer formed or laminated on a transparent protective plate such as glass, acrylic resin, or polycarbonate can be used.

  When setting it as such a laminated body, the intermediate film 11 can be laminated | stacked using a roll lamination, a vacuum bonding machine, or a single wafer bonding machine.

<Method for producing laminated glass>
The laminated glass which concerns on this embodiment can be manufactured by the following method, for example. First, the light release separator 110 is peeled from the interlayer film for laminated glass to expose the surface of the intermediate film 11. Subsequently, the surface of the intermediate film 11 is attached to the first adherend (glass plate) and pressed with a roller or the like. Subsequently, the heavy release separator 120 is peeled from the intermediate film 11 to expose the surface of the intermediate film 11. Subsequently, the surface of the intermediate film 11 is attached to a second adherend (glass plate), and the obtained laminate is heated and pressurized by an autoclave or the like. The second adherend is, for example, a glass plate. In this way, the adherends can be bonded together via the intermediate film 11. The heating and pressurizing conditions are such that the temperature is 30 to 150 ° C. and the pressure is 0.3 to 1.5 MPa, but the temperature is 50 to 70 ° C. from the viewpoint of further removing entrained bubbles, and the pressure is It is preferable that it is 0.3-0.5 MPa. 5-60 minutes are preferable and, as for the time of a heating and pressurization, it is more preferable that it is 10-30 minutes.

  Before or after heating and pressurization, the intermediate film 11 may be irradiated with ultraviolet rays from either side of both adherends. Thereby, the adhesive reliability (reduction of bubble generation and suppression of peeling) and adhesive strength under high temperature and high humidity conditions can be further improved.

  The peel strength between the intermediate film 11 and the glass plates 21 and 22 is preferably 5 N / 10 mm or more, more preferably 8 N / 10 mm or more, and still more preferably 10 N / 10 mm or more. Further, it is preferably 30 N / 10 mm or less. The peel strength is measured as 180 degree peel (3 seconds at a peel rate of 300 mm / min, measurement temperature 25 ° C.) using a tensile tester (made by Orientec Co., Ltd., trade name “Tensilon RTC-1210”). be able to.

  The storage elastic modulus of the interlayer film is preferably 100 MPa to 100,000 MPa at a measurement temperature of 25 ° C. and a frequency of 100 Hz or more. The tan δ (loss factor) of the interlayer film is preferably 0.5 or more at a measurement temperature of 25 ° C. and a frequency of 100 Hz or more.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

1. Acrylic polymer <weight average molecular weight Mw>
The weight average molecular weight (Mw) of the acrylic polymer produced in the production example was determined as a converted value of standard polystyrene by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent. GPC equipment and measurement conditions are as follows. A calibration curve was prepared using 5 sample sets (PStQuick MP-H, PStQuick B [trade name, manufactured by Tosoh Corporation]) as standard polystyrene.
Device: High-speed GPC device HLC-8320GPC (detector: differential refractometer) (trade name, manufactured by Tosoh Corporation)
Solvent: Tetrahydrofuran (THF)
Column: Column TSKGEL SuperMultipore HZ-H (manufactured by Tosoh Corporation, trade name)
Column size: Column length is 15 cm, column inner diameter is 4.6 mm
Measurement temperature: 40 ° C
Flow rate: 0.35 mL / min Sample concentration: 10 mg / THF 5 mL
Injection volume: 20 μL

<Manufacture of acrylic polymer>
Production Example 1
In a reaction vessel equipped with a condenser, a thermometer, a stirrer, a dropping funnel and a nitrogen inlet tube, 85.0 g of 2-ethylhexyl acrylate, 10.0 g of 2-hydroxyethyl acrylate, one-end methacryloyl-modified polysiloxane compound (Shin-Etsu Chemical Co., Ltd.) Product name “X-22-2426”, ethylenically unsaturated group equivalent: 12000 g / mol) 5.0 g and ethyl acetate 145.0 g were added. The reaction solution in the reaction vessel was heated from room temperature (25 ° C.) to 65 ° C. in 15 minutes while purging with nitrogen at an air volume of 100 mL / min. Next, while maintaining at 65 ° C., a solution obtained by dissolving 0.1 g of lauroyl peroxide in 5.0 g of ethyl acetate was added, and the reaction was allowed to proceed for 8 hours. It adjusted with ethyl acetate so that solid content concentration might be 40 mass%, and the solution of copolymer A-1 (Mw: 700,000, glass transition temperature: -20 degreeC) which has a hydroxy group was obtained.

Production Example 2
It has hydroxy groups by operating in the same manner as in Production Example 1 except that 90.0 g of 2-ethylhexyl acrylate, 10.0 g of 2-hydroxyethyl acrylate, and 145.0 g of ethyl acetate are put in a reaction vessel to form a reaction solution. A solution (solid content concentration: 40% by mass) of copolymer A-2 (Mw: 700,000, glass transition temperature: −20 ° C.) was obtained.

Production Example 3
90.0 g and 2 of 2-ethylhexyl acrylate (manufactured by Wako Pure Chemical Industries, Ltd., trade name “EHA”) as an initial monomer was attached to a reaction vessel equipped with a cooling pipe, a thermometer, a stirring device, a dropping funnel and a nitrogen introduction pipe. -10.0 g of hydroxyethyl acrylate (trade name “HEA” manufactured by Osaka Organic Chemical Industry Co., Ltd.) and 300.0 g of methyl ethyl ketone were added. The reaction solution in the reaction vessel was heated from 25 ° C. to 80 ° C. for 15 minutes while replacing the nitrogen with an air volume of 100 ml / min. Next, 27.0 g of 2-ethylhexyl acrylate and 3.0 g of 2-hydroxyethyl acrylate as additional monomers were dissolved in 5.0 g of t-butylperoxy-2-ethylhexanoate while maintaining at 80 ° C. The solution was added dropwise over 120 minutes. After completion of the dropwise addition, the reaction was further allowed to proceed for 2 hours. It adjusted with methyl ethyl ketone so that solid content concentration might be 40 mass%, and the solution of copolymer A-3 (Mw: 30000, glass transition temperature: -20 degreeC) was obtained.

2. Production of Hollow Silica Particles Cubic calcium carbonate particles were formed by crystal growth. The obtained calcium carbonate particles were aged while being dehydrated to obtain a slurry of hydrous calcium carbonate particles. The slurry was dispersed in ethanol, silicon alkoxide and ammonia were added thereto, and the calcium carbonate particles were coated with silica (SiO ₂ ) by a sol-gel method. The silica coated particles were washed and dispersed in water. Hydrochloric acid was added to the obtained dispersion to dissolve and flow out calcium carbonate inside the particles to form hollow silica particles having a cubic outer shell (silica shell) having pores formed by the flow. . After drying, the hollow silica particles were further heated at 400 ° C. for 0.5 hours to block the pores formed by the outflow. Through the above operation, hollow silica particles having a silica shell as an outer shell (a porosity of 59% by volume, an outer diameter of 100 nm, an inner diameter of 84 nm, and a shell thickness of 8 nm) were produced. This hollow silica particle was used to form the following interlayer film.

3. Laminated glass production example 1
(Film material for forming the first layer)
A mixture of 1000 parts by mass of ethyl acetate and 100 parts by weight of hollow silica particles was mixed using a stirrer to obtain a dispersion. This dispersion and the solution of copolymer A-1 were mixed using a stirrer to obtain a first layer-forming coating solution. The ratio of the dispersion was 250 parts by mass (125 parts by mass of hollow silica particles) with respect to 100 parts by mass of copolymer A-1 in the solution.
The obtained coating liquid was applied to a polyethylene terephthalate film (thickness 75 μm) whose surface was release-treated using a bar coater, and the coating film was dried by heating at 100 ° C. for 10 minutes to obtain a resin layer (thickness). 50 μm) was formed. On the formed resin layer, a polyethylene terephthalate film (thickness 75 μm) subjected to a release treatment was covered, and this was attached with a 1.0 kgf hand roller to obtain a film material for forming a first layer.

(Film material for forming second and third layers)
A polyisocyanate compound (Tosoh Corporation, product name “Coronate HL”) is mixed with the solution of copolymer A-1 as a thermal crosslinking agent to prepare coating solutions for forming the second layer and the third layer. did. The proportion of the thermal crosslinking agent was 0.2 parts by mass with respect to 100 parts by mass of the copolymer A-1 in the solution.
The obtained coating liquid was applied to a polyethylene terephthalate film (thickness 75 μm) whose surface was release-treated using a bar coater, and the coating film was dried by heating at 100 ° C. for 10 minutes to obtain a resin layer (thickness 25 μm). ) Was formed. On the formed resin layer, a polyethylene terephthalate film (thickness 75 μm) subjected to a release treatment was covered and pasted with a 1.0 kgf hand roller to obtain film materials for forming the second and third layers.

(Multilayer interlayer)
A film having a multilayered intermediate film sandwiched between two polyethylene terephthalate films by laminating a polyethylene terephthalate film from each film material and laminating in the order of the second layer, the first layer, and the third layer. The material was obtained. During lamination, pressure was applied with a 1.0 kgf hand roller.

(Laminated glass)
One polyethylene terephthalate film was peeled from the film material having the intermediate film. The exposed surface of the interlayer film was attached to float glass having a length of 110 mm, a width of 110 mm, and a thickness of 2.7 mm, and pressed with a roller. Next, the other polyethylene terephthalate film is peeled off, and the exposed intermediate film surface is attached to a second adherend float glass having a length of 110 mm, a width of 110 mm, and a thickness of 2.7 mm using a vacuum laminator. Thus, a laminate having a structure of float glass / intermediate film / float glass was produced. This laminated body was heated and pressurized by an autoclave under conditions of a temperature of 50 ° C., a pressure of 0.5 MPa, and a holding time of 30 minutes to obtain a laminated glass.

Example 2
A polyisocyanate compound (Tosoh Corporation, product name “Coronate HL”) as a thermal crosslinking agent and a dispersion of hollow silica particles were mixed with the solution of copolymer A-1, to prepare a coating solution. The proportion of the thermal crosslinking agent was 0.2 parts by mass and the proportion of the dispersion was 250 parts by mass (125 parts by mass of hollow silica particles) with respect to 100 parts by mass of Copolymer A-1 in the coating liquid.
The obtained coating liquid was applied to a polyethylene terephthalate film (thickness 75 μm) whose surface was release-treated using a bar coater, and the coating film was dried by heating at 100 ° C. for 10 minutes to obtain an intermediate film (thickness 100 μm). ) Was formed. The formed intermediate film was covered with a polyethylene terephthalate film (thickness 75 μm) that had been subjected to a release treatment, and was attached with a 1.0 kgf hand roller to obtain a film material having a single-layer intermediate film.
A laminated glass was produced in the same manner as in Example 1 except that the obtained film material was used.

Example 3
A laminated glass was obtained in the same manner as in Example 2 except that the solution of copolymer A-2 was used instead of the solution of copolymer A-1.

Example 4
A laminated glass was obtained in the same manner as in Example 2 except that the solution of the copolymer A-3 was used instead of the solution of the copolymer A-1.

Comparative Example 1
A polyisocyanate compound (Tosoh Corporation, product name “Coronate HL”) as a thermal crosslinking agent was mixed into the solution of copolymer A-3 to prepare a coating solution. The proportion of the thermal crosslinking agent was 0.2 parts by mass with respect to 100 parts by mass of the copolymer A-1 in the solution.
The obtained coating liquid was applied to a polyethylene terephthalate film (thickness 75 μm) whose surface was release-treated using a bar coater, and the coating film was dried by heating at 100 ° C. for 10 minutes to obtain an intermediate film (thickness 100 μm). ) Was formed. The formed intermediate film was covered with a polyethylene terephthalate film (thickness 75 μm) that had been subjected to a release treatment, and was attached with a 1.0 kgf hand roller to obtain a film material having a single-layer intermediate film.
A laminated glass was produced in the same manner as in Example 1 except that the obtained film material was used.

Comparative Example 2
100 parts by mass of polyvinyl butyral resin and 40 parts by mass of triethylene glycol bis (2-ethylhexanoate) as a plasticizer were mixed and sufficiently melt-kneaded with a mixing roll. The kneaded product was press-molded with a press molding machine at 150 ° C. for 30 minutes to obtain a resin film having a thickness of 380 μm, which was used as an interlayer film for laminated glass. A polyvinyl butyral resin having a half width of a peak corresponding to a hydroxyl group in an infrared absorption spectrum of 245 cm ⁻¹ , an acetalization degree of 68.0 mol%, and a vinyl acetate component ratio of 0.6 mol% was used. .
The obtained interlayer film for laminated glass was sandwiched between float glass having a length of 110 mm, a width of 110 mm, and a thickness of 2.7 mm, which was put in a rubber bag and deaerated at a vacuum degree of 2660 Pa for 20 minutes. The rubber pack was transferred to an oven while being deaerated, and the laminate of float glass / interlayer film / float glass was further pressurized by a vacuum press at 90 ° C. for 30 minutes. The laminated body preliminarily pressure-bonded in this manner was pressure-bonded by further pressing for 20 minutes under conditions of 135 ° C. and pressure 118 N / cm ^{2 in} an autoclave to obtain a laminated glass.

4). Evaluation <Insulation test>
An interlayer film for laminated glass was bonded to one stainless steel (SUS) substrate (a disk having a diameter of 60 mm and a thickness of 5 mm) to produce a sample for heat insulation evaluation. The prepared sample was sandwiched between two metal plates at a pressure of 0.4 MPa, and the thermal conductivity was measured using a thermal conductivity measuring device (“HC-110” manufactured by Eiko Seiki Co., Ltd.).

<Splitability test>
FIG. 7 is an exploded perspective view schematically showing a method for evaluating the splitting property of laminated glass. A laminated glass is disposed between a support portion 140 having a frame-shaped flange portion 141 having a rectangular inner periphery of 100 mm × 100 mm and a frame-shaped fixing portion 142 having substantially the same shape as the flange portion 141, and in this state, screws The laminated glass is fixed by a fixing member such as. To a position within 25 mm from the center point of the fixed laminated glass, a steel ball 143 having a mass of about 1040 g and a diameter of 63.5 mm is dropped from 5 cm to 100 cm while increasing the height in steps of 5 cm, The height at which the laminated glass broke was recorded. A test was performed on six laminated glasses each having an intermediate film, and the average height was calculated.

<Evaluation of foam resistance>
Change one float glass to a float glass with a length of 70 mm, a width of 50 mm, and a thickness of 2 mm, and change the other float glass to a polycarbonate plate with a length of 70 mm, a width of 50 mm, and a thickness of 2 mm. According to the same procedure, a sample for evaluation of foam resistance having a structure of float glass / interlayer film / polycarbonate plate was produced. After each sample for evaluation was treated under the following conditions, the sample was taken out and visually checked for foaming. In Table 1, “A” indicates that no foaming occurred in the sample under any of the treatment conditions, and “B” indicates that foaming occurred in the sample under the high temperature and high humidity test conditions, and the high temperature test and heat cycle test. Indicates that foaming did not occur, and “C” indicates that foaming occurred in the sample under any of the processing conditions.

(Processing conditions)
(1) High temperature and high humidity test The sample was allowed to stand for 24 hours under conditions of 85 ° C and 85% RH.
(2) High temperature test The sample was allowed to stand at 85 ° C for 24 hours.
(3) Heat cycle test The sample was allowed to stand in a -30 ° C atmosphere for 30 minutes and then subjected to a heat cycle of 20 times in an 85 ° C atmosphere for 30 minutes.

<Measurement of haze>
Haze is a value (%) representing turbidity, and when the laminated glass is irradiated with a lamp, the total transmittance T _{t of} light transmitted through the laminated glass and diffused and scattered in the laminated glass. From the light transmittance T _{d, it is obtained} from the formula: haze = (T _d / T _t ) × 100. These are defined by JIS K 7136. NDH-5000 manufactured by Nippon Denshoku Industries Co., Ltd. was used as a measuring device.

Table 2 shows the structure and evaluation results of the intermediate layer of each laminated glass. The laminated glass of the example having an interlayer film containing hollow silica particles showed excellent characteristics not only in haze and splitting resistance but also in heat insulation and foam resistance.

  DESCRIPTION OF SYMBOLS 2 ... 1st layer, 3 ... 2nd layer, 4 ... 3rd layer, 5 ... Resin composition, 10, 11 ... Intermediate film for laminated glass, 12 ... Film material which has intermediate film, 21, 22 ... Glass plate, 30, 31 ... laminated glass, 51 ... hollow silica particles, 52 ... hollow part, 53 ... outer shell part, 110 ... light release separator, 120 ... heavy release separator.

Claims (10)

A curable resin composition containing an acrylic polymer, and a hollow silica particle, an interlayer film for laminated glass,
The porosity of the hollow silica particles is 40% or more and 80% or less,
The interlayer film for laminated glass is a single-layer film in which the hollow silica particles are distributed throughout the interlayer film for laminated glass, or the first layer containing the hollow silica particles and one of the main layers thereof An interlayer film for laminated glass, which is a multilayer film having a second layer provided on the surface side and containing the curable resin composition.   The interlayer film for laminated glass according to claim 1, which is a multilayer film having the first layer containing the hollow silica particles and the second layer provided on one main surface side thereof.   The interlayer film for laminated glass according to claim 2, wherein the second layer is laminated in contact with the first layer.   The interlayer film for laminated glass according to claim 2 or 3, further comprising a third layer provided on the other main surface side of the first layer and containing the curable resin composition.   The interlayer film for laminated glass according to claim 4, wherein the third layer is laminated in contact with the first layer.   The thickness of the said 1st layer is 0.005T or more and 0.6T or less when the thickness of the said intermediate film for laminated glasses is T (micrometer), It is any one of Claims 2-5. Interlayer film for laminated glass.   The acryl polymer is a siloxane which is an acrylic monomer having a (meth) acryloyl group, an ethylenically unsaturated group, an ethylenically unsaturated group equivalent of 2000 to 20000 g / mol, and a compound different from the acrylic monomer. The interlayer film for laminated glass according to any one of claims 1 to 6, which is a copolymer containing a compound as a monomer unit.   The interlayer film for laminated glass according to any one of claims 1 to 7, wherein the acrylic polymer has a weight average molecular weight of 100,000 or more and a glass transition temperature of the acrylic polymer of -10 ° C or lower. The content of the hollow silica particles is 0.1 g / m ² or more and 80 g / m ² or less, based on the area of the main surface of the interlayer film for glass, according to any one of claims 1 to 8. The interlayer film for laminated glass described. Two opposing glass plates, and an intermediate film sandwiched between the two glass plates,
Laminated glass, wherein the intermediate film is an intermediate film for laminated glass according to any one of claims 1 to 9, wherein the curable resin composition is cured.

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