JP2007070200A - Laminated glass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide laminated glass which maintains durability to water although it uses an interlayer film having a layer constitution comprising only a sound insulating layer or a sound insulating layer having a thickness not thinner than that of a usually used layer. <P>SOLUTION: The laminated glass 10 is constituted of glass plates 11a, 11b and the interlayer film 12 which is interposed between the glass plates 11a, 11b and comprises the sound insulating layer 21 containing a polyvinylacetal resin having an acetalization degree of 60-85 mol%, an alkali metal salt and/or an alkaline earth metal salt, and a plasticizer so that the amounts of the plasticizer and the metal salt are >30 parts by mass and 0.001-1.0 parts by mass, respectively, per 100 parts by mass of the polyvinylacetal resin. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminated glass excellent in sound insulation performance, and more particularly to a laminated glass suitable for a vehicle window.

  In order to shield sound from window openings of automobiles and buildings, it has been proposed to use laminated glass for automobile windows and architectural windows. This is because laminated glass has better sound insulation performance than single plate glass.

The sound insulation performance is represented by the amount of sound transmission loss (hereinafter simply referred to as transmission loss) corresponding to a change in frequency. In general, the transmission loss increases as the sound frequency increases. On the other hand, there is a phenomenon called transmission coincidence effect in which transmission loss decreases in a certain frequency region. This phenomenon is a phenomenon in which transmission loss decreases due to resonance between vibration of a plate material (hereinafter referred to as sound excitation vibration) based on excitation by sound and a sound wave incident on the plate material. Frequency domain transmission loss decreases, a frequency region around coincidence frequency f _c. Therefore, the following two methods are effective for improving the sound insulation performance. One is to design the structure of the plate such that the frequency higher coincidence frequency f _c, the other is by suppressing the sound vibration vibration of the plate.

The principle that the first method is effective in improving the sound insulation performance can be explained as follows. Since the transmission loss is large the higher the frequency of the sound to be generated is coincidence effect, if coincidence frequency f _c is the high frequency side, the transmission loss of the absolute value as compared with the case where Koninshidensu effect at low frequency side occurs large. Coincidence frequency f _c is inversely proportional to the square root of the Young's modulus of the plate. Therefore, when a single glass plate and a laminated glass having the same thickness are compared, it is understood that the laminated glass in which an interlayer film having a small Young's modulus is arranged between a plurality of glass plates has better sound insulation performance.

  The principle that the second method is effective in improving the sound insulation performance can be explained as follows. Since the coincidence effect is due to the resonance between the sound excitation vibration of the plate and the sound wave incident on the plate, the coincidence effect can be reduced if the sound vibration is suppressed so as not to resonate with the sound wave. When two glass plates are separated by an intermediate film, an intermediate film having a smaller shear storage modulus than that of the glass plate can absorb vibration transmitted from one glass plate to the other glass plate. Even if the other glass plate vibrates, the intermediate film having a small shear storage elastic modulus causes a phase shift of vibrations of both glass plates and causes an interference phenomenon of both vibrations. As a result, vibration of the plate material is suppressed. Further, such an intermediate film is supposed to convert vibration energy generated by incident sound waves into heat energy and absorb vibration energy. Therefore, it can be seen that the laminated glass in which the intermediate film is arranged between the plurality of glass plates has better sound insulation performance than the single plate glass.

  As an interlayer film for laminated glass, a polyvinyl butyral (hereinafter referred to as PVB) film is usually used. The Young's modulus of a general PVB film exhibits a sufficiently small value at a temperature of 30 ° C. or higher so as to shield a sound having a frequency to be sound-insulated in an environment where a human being such as a building or a car is used. However, the Young's modulus of the PVB film at a temperature of about 20 ° C. or less does not become a value small enough to cut off the sound of the frequency to be sound-insulated in an environment where a human being is in a building or in an automobile. Furthermore, the shear storage elastic modulus of the PVB film at a temperature of about 20 ° C. or less does not become a value large enough to cause a shift in the vibration phase of each of the two glass plates and cause an interference phenomenon. Therefore, laminated glass using ordinary PVB film contributes to a comfortable environment for humans in buildings and automobiles at temperatures of 30 ° C or higher, but in buildings and at temperatures below 20 ° C. It is thought that it is not possible to contribute to an environment in which humans can comfortably live in automobiles.

  In order to eliminate such temperature dependency of the sound insulation performance of the PVB film, Patent Document 1 and Patent Document 2 propose to form a PVB film from a plurality of films. Specifically, the intermediate film disclosed in these publications is a laminated film in which a plurality of films having different plasticizer contents are laminated, or a laminated film in which a plurality of films having different temperatures at which the loss coefficient is maximized are laminated. It is. Thus, it is said that a laminated glass that does not deteriorate the sound insulation performance even at a temperature below the room temperature region is obtained.

  The intermediate films described in these patent documents exhibit a layer structure in which two types of layers are stacked. Conceptually, one of the two types of layers is the same layer as a normal intermediate film (hereinafter referred to as “normal layer”), and the other layer is a softer and stickier layer than the normal intermediate film (hereinafter referred to as “normal layer”). "Sound insulation layer"). The phenomenon that the sound insulation performance can be maintained even at a temperature of 20 ° C. or less by the interlayer film having such a layer structure can be said to be because the sound insulation layer is sufficiently softer than the normal layer even at a temperature of room temperature or less.

  The sound insulation layer is generally a layer that is usually thinner than the membrane. The reason is that the sound insulation layer is soft even at room temperature, so that it is easy to handle the intermediate film, such as during the production of laminated glass. However, if a normal intermediate film and an intermediate film having a sound insulating layer are mixed in the laminated glass process, it is difficult to distinguish between the two. The reason is that since the sound insulation layer is thinner than the normal layer, the appearance cannot be distinguished, and it is difficult to visually distinguish the two. Therefore, it is desired that the sound insulation layer alone or the sound insulation layer is an intermediate film having a thickness equivalent to or greater than that of the normal layer. Such an intermediate film having only a sound insulation layer is introduced in, for example, Patent Document 3.

JP 2001-206741 A JP 2000-272937 A JP-A-8-109048

  In order to make the intermediate film as disclosed in Patent Document 3 a soft intermediate film as its basic idea, a large amount of plasticizer is added. In order to increase the amount of the plasticizer, it is necessary to reduce the number of hydroxyl groups in the polyvinyl acetal resin used as the intermediate film material. Therefore, a soft intermediate film can be formed by reducing the number of hydroxyl groups and facilitating the introduction of the plasticizer.

  However, it has been found that the laminated glass using the interlayer film formed in this way may become cloudy when subjected to a water resistance test, and the water resistance is lowered. The decrease in water resistance is unthinkable from ordinary technical common sense. The reason is as follows. That is, the intermediate film formed on the basis of the above-described idea has fewer hydroxyl groups. It is said that water resistance is likely to be improved because there is a tendency to inhibit the affinity with water when the number of hydroxyl groups is small. As a result, the water resistance of the laminated glass produced has been lowered.

  An object of the present invention is to provide a laminated glass that does not reduce water resistance, using an intermediate film having a layer structure that includes only a sound insulating layer or a sound insulating layer that is not thinner than a normal layer.

  When the soft intermediate film as described above is used, a sticky feeling on the film surface is generated, and there has been a concern that the adhesive strength with the glass plate becomes too large when used for laminated glass. As a countermeasure for preventing the adhesive force from being increased, it is conceivable to add an adhesive force adjusting agent, specifically, a metal salt of a carboxylic acid having 2 to 16 carbon atoms more than a normal intermediate film. The inventors of the present invention pay attention to this adhesive strength adjusting agent, and as a result of considering the factors that hinder the improvement of water resistance even though the number of hydroxyl groups is small, the adhesive strength is adjusted simply because there is a sticky feeling. It was thought that there was no need to add a large amount of the agent, and invented as follows.

  That is, the present invention is a laminated glass comprising a plurality of glass plates and an intermediate film interposed between the plurality of glass plates, wherein the intermediate film has an acetalization degree of 60 to 85 mol%. A polyvinyl acetal resin, an alkali metal salt and / or an alkaline earth metal salt, and a plasticizer, wherein the plasticizer exceeds 30 parts by mass with respect to 100 parts by mass of the polyvinyl acetal resin, and the alkali metal There is provided a laminated glass characterized by having a sound insulation layer in which the salt and / or alkaline earth metal salt is 0.001 to 1.0 part by mass.

  According to the present invention, as the sound insulation layer, the alkali metal salt and / or the alkaline earth metal salt is 0.001 to 1.0 part by mass, particularly 0.01 to 0.2 part by mass with respect to 100 parts by mass of the polyvinyl acetal resin. By using the intermediate film having the layer, a laminated glass excellent in water resistance can be obtained while maintaining the adhesive strength of a predetermined glass plate.

  Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the laminated glass of the present invention. The basic configuration of the laminated glass 10 in this example is two glass plates 11 a and 11 b and an intermediate film 12. The glass plates 11a and 11b are laminated via the intermediate film 12. The intermediate film 12 in this example includes a polyvinyl acetal resin having an acetalization degree of 60 to 85 mol%, an alkali metal salt and / or an alkaline earth metal salt, and a plasticizer, and the polyvinyl acetal resin has a mass of 100 mass. It consists of the sound insulation layer 21 whose plasticizer exceeds 30 mass parts and metal salt is 0.001-1.0 mass part with respect to a part.

  FIG. 2 is a schematic sectional view showing another example of the laminated glass of the present invention. The basic configuration of the laminated glass 10 ′ in this example is two glass plates 11 a and 11 b and an intermediate film 12 ′. The glass plates 11a and 11b are laminated via an intermediate film 12 '. In the intermediate film 12 ′ in this example, the sound insulating layer 21 is sandwiched between the normal layers 22 a and 22 b, and the layer structure of the normal layer 22 a / the sound insulating layer 21 / the normal layer 22 b is exhibited. The sound insulating layer 21 comprises a polyvinyl acetal resin having an acetalization degree of 60 to 85 mol%, an alkali metal salt and / or an alkaline earth metal salt, and a plasticizer, as in the example of FIG. The plasticizer is 30 parts by mass or more and the metal salt is 0.001 to 1.0 parts by mass with respect to 100 parts by mass of the acetal resin. The normal layers 22a and 22b include a polyvinyl acetal resin having an acetalization degree smaller than that of the polyvinyl acetal resin of the sound insulating layer, an alkali metal salt and / or an alkaline earth metal salt, and a plasticizer. The plasticizer is 30 parts by mass or less and the metal salt is 0.001 to 1.0 part by mass with respect to 100 parts by mass of the polyvinyl acetal resin.

  The intermediate film in the present invention may be composed of a sound insulation layer as shown in FIG. 1, or may have a laminated structure of a sound insulation layer and other layers as shown in FIG. In the case of a laminated structure, even if the sound insulation layer is the outermost layer, the sound insulation layer may not be exposed to the outside by other layers as shown in FIG. The number of layers can also be determined as appropriate, such as 2 layers, 3 layers, 4 layers, and the like. In this case, at least one layer is a sound insulation layer, but there may be two or more sound insulation layers. The intermediate film is preferably composed of a sound insulating layer as shown in FIG. 1 because it can be easily found from the appearance that the intermediate film has a sound insulating performance in the laminated glass production process. Also in the case of a laminated structure, it is preferable that the thickness of the sound insulation layer is 10 times or more that of the other layers from the viewpoint of facilitating discrimination of the intermediate film having sound insulation performance.

As described above, the interlayer film in the present invention is an interlayer film having a sound insulation performance, and the interlayer film in the present invention has a sound insulation layer in order to improve the sound insulation performance. In order to improve the sound insulation performance, it can be said that the sound insulation layer is a qualitatively soft layer. “Soft” can be explained, for example, by the value storage elastic modulus G ′ indicating softness as follows. That is, the storage elastic modulus G ′ in a linear dynamic viscoelasticity test measured at a temperature of 20 ° C. and a frequency range of 5.0 × 10 ^{1 to} 1.0 × 10 ² Hz while changing the frequency by a shear method is 30 MPa or less. One layer can be said to be a soft layer. The storage elastic modulus G ′ of the sound insulation layer is preferably 10 MPa or less, more preferably 5 MPa or less.

In the case of the laminated structure, it can be said that the layers other than the sound insulation layer are not softer than the sound insulation layer. As a specific example, the other layer can be said to be a layer having a storage elastic modulus G ′ of 10 MPa or more at a temperature of 20 ° C. and a frequency of 5.0 × 10 ^{1 to} 1.0 × 10 ² Hz. In the case of a laminated structure, the thickness of the sound insulation layer is preferably 20% or more of the entire thickness of the intermediate film, and preferably 50% or more from the viewpoint of discrimination in the laminated glass manufacturing process.

  Such a layer that is not soft compared to the sound insulation layer can be obtained, for example, as follows. (1) The content of the plasticizer is 5 parts by mass or less than that of the sound insulation layer with respect to 100 parts by mass of the polyvinyl acetal resin. (2) The degree of acetalization of the polyvinyl acetal resin is made smaller than the degree of acetalization of the polyvinyl acetal resin of the sound insulation layer. Furthermore, the methods (1) and (2) can be combined.

  The thickness of the interlayer film in the present invention is preferably 0.5 to 3 mm. In particular, in the case of an intermediate film made of a sound insulating layer, the thickness is preferably 0.7 to 2 mm. Furthermore, in the case of an intermediate film composed of a laminated structure of a sound insulating layer and another layer, the thickness of the sound insulating layer is preferably 20% or more, and particularly preferably 50% or more of the total thickness of the intermediate film. Thereby, it can be easily determined that the interlayer film has sound insulation performance in the manufacturing process of the laminated glass.

  As described in the description of the sound insulating layer in FIGS. 1 and 2, the sound insulating layer in the present invention includes a polyvinyl acetal resin having an acetalization degree of 60 to 85 mol%, an alkali metal salt and / or an alkaline earth metal salt, and plastic. An agent. The plasticizer is 30 parts by mass or more and the metal salt is 0.001 to 1.0 parts by mass with respect to 100 parts by mass of the polyvinyl acetal resin. The metal salt is preferably 0.01 to 0.2 parts by mass with respect to 100 parts by mass of the polyvinyl polyvinyl acetal resin. The plasticizer is preferably 40 parts by mass or more, more preferably 45 parts by mass or more, and particularly preferably 60 parts by mass or more with respect to 100 parts by mass of the polyvinyl polyvinyl acetal resin. Thereby, a sound insulation layer can be made into a soft layer.

  In order to introduce such a large amount of plasticizer, the polyvinyl acetal resin contained in the sound insulation layer in the present invention has an acetalization degree of 60 to 85 mol%, preferably 65 to 80 mol%. In the present specification, the “degree of acetalization” means that the acetal group of the polyvinyl acetal resin is formed by acetalizing two hydroxyl groups of the polyalcohol resin as a raw material. Calculated by the method of counting.

As the polyvinyl acetal resin, a polyvinyl acetal resin having a half-value width of a hydroxyl group peak of 250 cm ⁻¹ or less when an infrared absorption spectrum is measured is preferable. More preferably, it is 200 cm ⁻¹ or less. In addition, an infrared absorption spectrum can be measured from the peak corresponding to a hydroxyl group among the obtained peaks, for example, by obtaining an infrared absorption spectrum using “FT-IR” manufactured by HORIBA. In this way, it is possible to reduce the number of hydroxyl groups contained in the material of the sound insulation layer and to effectively introduce a large amount of plasticizer.

Since the adhesive force between the intermediate film and the glass plate must not be too large, an adhesive force adjusting agent is added to the intermediate film material. Specifically, in the present invention, an alkali metal salt and / or an alkaline earth metal salt is used as an adhesive force adjusting agent for the material of the sound insulation layer. At this time, the content of the metal salt is 0.001 to 1.0 part by mass with respect to 100 parts by mass of the polyvinyl acetal resin in order to improve the water resistance in the laminated glass state while maintaining a desired adhesive force. . Furthermore, since a large amount of the metal salt as an absolute amount directly affects the water resistance, the metal salt has a content per unit area in the surface direction of the sound insulation layer of 0.05 to 0.3 g / it is preferable that the cm ^2.

  Examples of the alkali metal salt and / or alkaline earth metal salt used as the adhesive strength adjusting agent include salts of potassium, sodium, magnesium and the like. The acid constituting these salts is not particularly limited, and examples thereof include organic acids of carboxylic acids such as octylic acid, hexyl acid, butyric acid, acetic acid, formic acid, and inorganic acids such as hydrochloric acid and nitric acid. Among such alkali metal salts and / or alkaline earth metal salts, more preferred are alkali metal salts and alkaline earth metal salts of organic acids having 2 to 16 carbon atoms, and metals of carboxylic acids having 2 to 16 carbon atoms. A salt is particularly preferred. Specifically, for example, pentanoic acid metal salt (carbon number 5), hexanoic acid (2-ethylbutanoic acid) metal salt (carbon number 6), heptanoic acid metal salt (carbon number 7), octanoic acid metal salt (carbon number) 8) and the like.

  Moreover, a C2-C16 carboxylic acid magnesium salt and a C2-C16 carboxylic acid potassium salt are preferable. The carboxylic acid magnesium salt or potassium salt of an organic acid having 2 to 16 carbon atoms is not particularly limited, and examples thereof include magnesium acetate, potassium acetate, magnesium propionate, potassium propionate, magnesium 2-ethylbutanoate, and 2-ethylbutanoic acid. Potassium, magnesium 2-ethylhexanoate, potassium 2-ethylhexanoate and the like are preferably used. These may be used independently and 2 or more types may be used together.

  As a method for producing a polyvinyl acetal resin, for example, polyvinyl alcohol is dissolved in warm water, and the obtained polyvinyl alcohol aqueous solution is kept at 0 to 90 ° C., preferably 10 to 20 ° C. The acetalization reaction is allowed to proceed with stirring, the reaction temperature is raised to 70 ° C. to complete the reaction, followed by neutralization, washing with water and drying to obtain a polyvinyl acetal resin powder. It is done.

  The aldehyde is not particularly limited, and examples thereof include propionaldehyde, n-butyraldehyde, isobutyraldehyde, valeraldehyde, n-hexylaldehyde, 2-ethylbutyraldehyde, n-heptylaldehyde, n-octylaldehyde, n-nonylaldehyde, n -Aliphatic, aromatic, and alicyclic aldehydes such as decylaldehyde, benzaldehyde, and cinnamaldehyde. Preferably, they are C4-C8 n-butyraldehyde, n-hexyl aldehyde, 2-ethyl butyraldehyde, n-octyl aldehyde. The n-butyraldehyde having 4 carbon atoms is more preferable because it is excellent in weather resistance and can be easily produced by using the resulting polyvinyl acetal resin. These may be used alone or in combination of two or more.

  The polyvinyl acetal resin may be cross-linked. By using the cross-linked polyvinyl acetal resin, bleeding out of the plasticizer can be suppressed. As a method of crosslinking the polyvinyl acetal resin, for example, when polyvinyl alcohol is acetalized with an aldehyde such as butyraldehyde, a dialdehyde such as glutaraldehyde is used to slightly crosslink between the molecules by a diacetal bond; After at least 90% of the desired degree of acetalization in the acetalization reaction of polyvinyl alcohol is reached, an acid catalyst is added thereto and reacted at 60 to 95 ° C. to crosslink the polyvinyl acetal molecules by monobutyral bonds. Method: A method of adding a crosslinking agent that reacts with a hydroxyl group remaining in the obtained polyvinyl acetal resin and crosslinking the hydroxyl group; a method of crosslinking a hydroxyl group remaining in the polyvinyl acetal resin with diisocyanate or polyvalent epoxy, and the like.

  Examples of the crosslinking agent that reacts with a hydroxyl group include glyoxazal, dialdehyde containing a sulfur atom in the molecular chain, glyoxazal-ethylene glycol reaction product, polyvinyl alcohol modified with aldehyde at both ends, dialdehyde starch, Dialdehydes such as polyacrolein, methylols such as N-methylol urea, N-methylol melamine, trimethylol melamine, hexamethylol melamine, α-hydroxyethyl sulfonic acid, epichlorohydrin, polyethylene glycol diglycidyl ether, diglycidyl etherified Bisphenol A type epoxy resin, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, diglycidyl etherified glycerin, 3 or more in the molecular chain Polyglycol having a lysidyl ether group, polyglycidyl ether modified product of trimethylolpropane, polyglycidyl ether modified product of sorbitol, polyglycidyl ether modified product of sorbitan, polyglycidyl ether modified product of polyglycerol, dicarboxylic acid , Michael addition products of triethylene glycol and methyl acrylate, polyacrylic acid, polycarboxylic acids such as a mixture of methyl vinyl ether-maleic acid copolymer and isobutylene-maleic anhydride copolymer, tolylene diisocyanate, phenylene Aromatic diisocyanates such as diisocyanate, 4,4′-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate , Lysine diisocyanate, aliphatic diisocyanates such as 4,4′-dicyclohexylmethane diisocyanate, isophorone diisocyanate, polyisocyanate blocked with polyphenol, acetylacetone, malonic acid diethyl ester, lactam, oxime, amide, tertiary alcohol, etc. Is mentioned.

  The plasticizer in the present invention is not particularly limited as long as it is usually used for a polyvinyl acetal resin, and a known plasticizer generally used as a plasticizer for an interlayer film can be used. Examples of such plasticizers include organic ester plasticizers such as monobasic acid esters and polybasic acid esters; organic phosphoric acid-based and organic phosphorous acid-based phosphoric acid-based plasticizers, and the like. These plasticizers may be used alone or in combination of two or more, and are used properly according to the type of the polyvinyl acetal resin in consideration of compatibility with the resin.

  The monobasic acid ester plasticizer is not particularly limited. For example, glycol such as triethylene glycol, tetraethylene glycol or tripropylene glycol, butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptylic acid, n-octyl Examples thereof include glycol esters obtained by reaction with an organic acid such as acid, 2-ethylhexylic acid, pelargonic acid (n-nonyl acid) or decyl acid. Among them, triethylene glycol-dicaproate, triethylene glycol-di-2-ethylbutyrate, triethylene glycol-di-n-octylate, triethylene glycol-di-2-ethylhexyl ester, etc. A monobasic organic acid ester of glycol is preferably used.

  The polybasic acid ester plasticizer is not particularly limited. For example, an ester of a polybasic organic acid such as adipic acid, sebacic acid or azelaic acid and a linear or branched alcohol having 4 to 8 carbon atoms. Etc. Of these, dibutyl sebacic acid ester, dioctyl azelaic acid ester, dibutyl carbitol adipic acid ester and the like are preferably used.

  The organic ester plasticizer is not particularly limited, and examples thereof include triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexoate, triethylene glycol dicaprylate, triethylene glycol di-n- Octoate, triethylene glycol di-n-heptate, tetraethylene glycol di-n-heptate, dibutyl sebacate, dioctyl azelate, dibutyl carbitol adipate and the like are preferably used.

  In addition, for example, ethylene glycol di-2-ethyl butyrate, 1,3-propylene glycol di-2-ethyl butyrate, 1,4-propylene glycol di-2-ethyl butyrate, 1,4-butylene glycol di-2 -Ethyl butyrate, 1,2-butylene glycol di-2-ethylene butyrate, diethylene glycol di-2-ethyl butyrate, diethylene glycol di-2-ethyl hexoate, dipropylene glycol di-2-ethyl butyrate, tri Ethylene glycol di-2-ethylpentoate, tetraethylene glycol di-2-ethylbutyrate, diethylene glycol dicapryate and the like can also be used as the plasticizer.

  There is no restriction | limiting in particular in a phosphoric acid type plasticizer, For example, a tributoxy ethyl phosphate, an isodecyl phenyl phosphate, a triisopropyl phosphite etc. are suitable.

  Of these plasticizers, diester compounds consisting of dicarboxylic acids and monohydric alcohols or consisting of monocarboxylic acids and dihydric alcohols are particularly preferably used.

  In the intermediate film in the present invention, functional fine particles, ultraviolet absorbers, and the like may be appropriately dispersed and blended. Moreover, it is preferable that the intermediate film in this invention is embossed etc. on the surface of the layer which contact | connects a glass plate. By performing embossing, the adhesive force between the interlayer film and the glass plate can be adjusted to a preferred range.

  For the glass plate in the present invention, inorganic, for example, ordinary soda lime silica glass can be used. In this case, it may be a colorless transparent glass or a colored transparent glass. In particular, it is preferable to use green colored transparent glass for at least one of the glass plates. In this case, it is more preferable that the green-based colored transparent glass has ultraviolet absorption performance and infrared absorption performance. In addition, tempered glass that has been subjected to tempering treatment (including tempered glass having a lower strength than ordinary tempered glass and double-strength glass), glass plates that have been subjected to various surface treatments such as heat ray shielding coating, etc. Various glass plates can be used. Furthermore, a transparent resin plate made of polycarbonate resin or acrylic resin, called organic glass, can be used.

  When using laminated glass for a vehicle window, the thickness of the plurality of glass plates is preferably 1.5 to 3.0 mm. In this case, the glass plates can have the same thickness or different thicknesses. When using laminated glass for an automobile window, for example, two glass plates are used, and both are made 2.0 mm thick or 2.1 mm thick. In addition, when using laminated glass for an automobile window, for example, the thickness of the glass plate disposed on the inside of the vehicle is less than 2 mm, and the thickness of the glass plate disposed on the outside of the vehicle is slightly over 2 mm. The total thickness can be reduced and the external force from the outside of the vehicle can be resisted. These glass plates may be flat or curved. Since vehicles, particularly automobile windows, are often curved, the glass plate is often curved.

  According to the laminated glass of the present invention, in order to facilitate the determination of the interlayer film having sound insulation performance in the laminated glass manufacturing process, it is made of a sound insulation layer, or the middle of the sound insulation layer is thicker than other layers. A membrane can be used. Specifically, the sound insulation layer has 0.001 to 1.0 parts by mass of the alkali metal salt and / or alkaline earth metal salt with respect to 100 parts by mass of the polyvinyl acetal resin. Can be made into glass. Therefore, a laminated glass that can be used for outdoor windows that are easily affected by moisture, such as architectural windows and vehicle windows, particularly automobile windows, can be obtained.

It is a schematic sectional drawing which shows an example of the laminated glass of this invention. It is a schematic sectional drawing which shows another example of the laminated glass of this invention.

Explanation of symbols

10, 10 ': Laminated glass 11a, b: Glass plate 12, 12': Intermediate film 21: Sound insulation layer 22a, b: Normal layer

Claims (10)

  A laminated glass comprising a plurality of glass plates and an intermediate film interposed between the plurality of glass plates, the intermediate film comprising a polyvinyl acetal resin having an acetalization degree of 60 to 85 mol%, An alkali metal salt and / or an alkaline earth metal salt and a plasticizer, wherein the plasticizer exceeds 30 parts by mass with respect to 100 parts by mass of the polyvinyl acetal resin, and the alkali metal salt and / or alkali A laminated glass comprising a sound insulating layer in which an earth metal salt is 0.001 to 1.0 part by mass.   The laminated glass of Claim 1 whose said alkali metal salt and / or alkaline-earth metal salt are 0.01-0.2 mass part with respect to 100 mass parts of said polyvinyl acetal resins.   The laminated glass according to claim 1 or 2, wherein the alkali metal salt and / or alkaline earth metal salt is a metal salt of a carboxylic acid having 2 to 16 carbon atoms. The sound insulation layer has a storage elastic modulus G ′ of 30 MPa or less in a linear dynamic viscoelasticity test measured while changing the frequency in a temperature region of 20 ° C. and a frequency range of 5.0 × 10 ^{1 to} 1.0 × 10 ² Hz. The laminated glass of Claim 1, 2, or 3. The laminated glass according to claim 1, 2, 3, or 4, wherein the polyvinyl acetal resin has a half-value width of a hydroxyl group peak of 250 cm ^-1 or less when an infrared absorption spectrum is measured. The alkali metal salt and / or alkaline earth metal salt has a content per unit area in the plane direction of the sound insulation layer of 0.05 to 0.3 g / cm ² , The laminated glass according to 5.   The laminated glass according to claim 1, 2, 3, 4, 5 or 6, wherein the intermediate film is composed of the sound insulating layer.   The intermediate film has a laminated structure composed of the sound insulating layer and another layer, and the other layer includes a polyvinyl acetal resin having an acetalization degree of 60 to 85 mol%, an alkali metal salt and / or an alkaline earth metal. A plasticizer and a plasticizer in an amount of 30 parts by mass or less, and the alkali metal salt and / or alkaline earth metal salt in an amount of 0.001 to 1 parts per 100 parts by mass of the polyvinyl acetal resin. The laminated glass according to claim 1, 2, 3, 4, 5 or 6, which is 0 part by mass.   The laminated glass according to claim 8, wherein a thickness of the sound insulating layer is 50% or more of a thickness of the entire intermediate film. The laminated glass according to claim 8 or 9, wherein the sound insulating layer is disposed between other layers provided with two or more layers.

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