JPH0826785A - Intermediate film for laminated glass and laminated glass using the same - Google Patents

Abstract

PURPOSE:To provide an intermediate film for sound insulating laminated glass which exhibits excellent sound-insulating properties and in which no optical distortion is generated and also to provide the high quality sound-insulating laminated glass using the intermediate film. CONSTITUTION:This intermediate film is formed by laminating two kinds of resin films and consists of at least two layers wherein: one resin film (A) is formed from a plasticized polyvinylacetal resin contg. a plasticizer and a polyvinylacetal resin (a) that is obtained by acetalizing a polyvinyl alcohol having an average degree of polymerization of 1000 to 2000 and a >=96mol% degree of saponification with an aldehyde having 4 to 10 carbon atoms; and the other resin film (B) is formed from a plasticized polyvinylacetal resin contg. a plasticizer and a polyvinylacetal resin (b) that is obtained by acetalizing a polyvinyl alcohol having an average degree of polymerization of 2000 to 3000 and a 70 to 92mol% degree of saponification with an aldehyde having 4 to 10 carbon atoms. The laminated glass produced through using this intermediate film is also provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound insulating laminated glass intermediate film suitable mainly for construction and the like, and a sound insulating laminated glass produced by using the intermediate film.

[0002]

2. Description of the Related Art Laminated glass obtained by bonding a pair of glass plates with an intermediate film formed by forming a transparent and highly flexible resin such as a plasticized polyvinyl acetal resin is a window for automobiles and buildings. Widely used as glass.

The above-mentioned laminated glass is excellent in adhesiveness, transparency, weather resistance and the like and has various properties such as not causing optical distortion and scattering of glass fragments, but has a drawback that it is inferior in sound insulation. . In particular, in the mid-high range around 2000 Hz, the sound insulation property is deteriorated due to the coincidence effect.

The coincidence effect is a phenomenon in which when a sound wave is incident on the glass, a transverse wave is conducted on the glass surface due to the rigidity and inertia of the glass, the transverse wave resonates with the incident sound, and the sound is transmitted. .

In recent years, the demand for sound insulation of laminated glass has been increasing more and more, and especially for laminated glass used for architectural window glass, glass fragments are not scattered at the time of breakage and it is of course highly safe. There is a strong demand for excellent sound insulation.

As an example of such an interlayer film for sound-insulating laminated glass, an aldehyde having 6 to 10 carbon atoms and 1 to 1 carbon atoms are used.
4 A layered film of two kinds of resin films made of polyvinyl acetal resin acetalized with two kinds of aldehydes and a resin made of a mixture of the above two kinds of polyvinyl acetal resins. An interlayer film for glass has been proposed (JP-A-4-254444).

However, since the interlayer film for sound-insulating laminated glass according to the above-mentioned proposal has a large difference in viscoelastic behavior such as the viscosity of two kinds of resin films to be laminated, when laminated or when it is used as laminated glass. There is a problem in that a minute disturbance occurs at the laminated interface of two types of resin films, and a phenomenon in which an image viewed through the obtained laminated glass looks distorted, so-called optical distortion easily occurs.

[0008]

DISCLOSURE OF THE INVENTION In order to solve the above-mentioned conventional problems, the present invention provides an interlayer film for a sound-insulating laminated glass which exhibits excellent sound insulation properties and does not cause optical distortion, and an intermediate film for the same. It is an object of the present invention to provide a high-quality sound insulating laminated glass produced by using the laminated glass.

[0009]

An intermediate film for laminated glass according to the invention of claim 1 (hereinafter referred to as "first invention") is formed by laminating two kinds of resin films, and at least two layers are formed. A laminated resin film having a structure, wherein one resin film (A) is polyvinyl alcohol having an average degree of polymerization of 1000 or more and less than 2000 and a degree of saponification of 96 mol% or more with an aldehyde having 4 to 10 carbon atoms. The polyvinyl acetal resin (a) obtained by acetalization and a plasticized polyvinyl acetal resin containing a plasticizer are formed into a film, and the other resin film (B) has an average degree of polymerization of 2000 to 3
And a saponification degree of 70 to 82 mol%, a plasticized polyvinyl acetal resin containing a polyvinyl acetal resin (b) obtained by acetalizing a polyvinyl alcohol having an aldehyde having 4 to 10 carbon atoms and a plasticizer is manufactured. It is characterized by being formed into a film, whereby the above object is achieved.

Further, in the laminated glass according to the invention of claim 2 (hereinafter referred to as "second invention"), at least a pair of glass and / or synthetic resin layers are adhered by the intermediate film according to the first invention. The above object is achieved thereby.

Polyvinyl acetal resin (a) which is the main component of the resin film (A) used for the intermediate film according to the first invention.
Has an average degree of polymerization of 1000 or more and less than 2000, more preferably 1300 or more and less than 2000, and a saponification degree of 9
The polyvinyl alcohol having 6 mol% or more has 4 to 4 carbon atoms.
It is necessary that the polyvinyl acetal resin be obtained by acetalizing with 10 aldehydes.

When the average degree of polymerization of the polyvinyl alcohol is less than 1000, the laminated glass obtained according to the second invention has poor penetration resistance. On the other hand, when the average degree of polymerization of the polyvinyl alcohol is 2000 or more, the viscosity difference between the resin film obtained and the resin film (B) described below becomes too large, and both resin films are laminated or laminated glass is produced. When doing so, a minute disturbance occurs at the laminated interface of both resin films, and optical distortion occurs in the obtained laminated glass.

When the saponification degree of the polyvinyl alcohol is less than 96 mol%, the resulting interlayer film has insufficient sound insulation.

The average degree of polymerization and the degree of saponification of polyvinyl alcohol in the first invention are determined according to JIS K-6726.
The average degree of polymerization and the degree of saponification measured according to the "polyvinyl alcohol test method".

The types of aldehyde having 4 to 10 carbon atoms for acetalizing the polyvinyl alcohol include n-butyraldehyde, iso-butyraldehyde, n-pentylaldehyde, n-hexylaldehyde, 2-ethylbutyraldehyde, Aliphatic, alicyclic or aromatic aldehydes such as n-heptyl aldehyde, n-octyl aldehyde, n-nonyl aldehyde, n-decyl aldehyde, benzaldehyde, cinnamaldehyde and the like can be mentioned, and one or more of these can be used. It is preferably used.

If the aldehyde has less than 4 carbon atoms, a polyvinyl acetal resin exhibiting sufficient sound insulation cannot be obtained, and conversely, the aldehyde has 1 carbon atom.
When it exceeds 0, the reactivity during the acetalization reaction remarkably decreases, and the rigidity and sound insulation of the obtained polyvinyl acetal resin decrease.

Among the aldehydes having 4 to 10 carbon atoms, n-butyraldehyde having 4 carbon atoms is particularly preferably used. The polyvinyl butyral resin (a) obtained by using n-butyraldehyde has excellent adhesiveness and weather resistance, and is easily manufactured.

The polyvinyl acetal resin (b) which is the main component of the resin film (B) used for the intermediate film according to the first invention has an average degree of polymerization of 2000 to 3000, more preferably 2000 to 2700. Saponification degree is 70-9
It is necessary that the polyvinyl acetal resin is obtained by acetalizing 2 mol%, more preferably 76 to 90 mol%, of polyvinyl alcohol with an aldehyde having 4 to 10 carbon atoms.

If the average degree of polymerization of the polyvinyl alcohol is less than 2000, the viscosity difference between the resin film obtained and the resin film (A) becomes too large, and both resin films are laminated or laminated glass is produced. When doing so, a minute disturbance occurs at the laminated interface of both resin films, and optical distortion occurs in the obtained laminated glass. On the other hand, if the average degree of polymerization of the polyvinyl alcohol exceeds 3000, molding of the resin film becomes difficult and the rigidity of the resin film becomes too strong, which is not preferable.

If the saponification degree of the polyvinyl alcohol is less than 70 mol%, blocking or the like is likely to occur during the production of the polyvinyl acetal resin, which makes the production difficult. On the contrary, when the saponification degree of the polyvinyl alcohol is 92 mol% or more, the resulting interlayer film has insufficient sound insulation.

As the aldehyde having 4 to 10 carbon atoms for acetalizing the polyvinyl alcohol, one or two or more aldehydes similar to those used for producing the polyvinyl acetal resin (a) are preferably used. Among them, n-butyraldehyde is more preferably used.

The degree of acetalization of the polyvinyl acetal resins (a) and (b) is not particularly limited, but is preferably 40 mol% or more, and more preferably 50 mol% or more. preferable. If the degree of acetalization is less than 40 mol%, the compatibility with the plasticizer is reduced, and the plasticizer may be contained in an amount necessary for ensuring the sound insulation of the interlayer film and the penetration resistance of the laminated glass. It will be difficult.

The degree of acetalization referred to herein is, when the polyvinyl acetal resin is a polyvinyl butyral resin, measured in accordance with JIS K-6728 "Polyvinyl butyral test method". In the case of a polyvinyl acetal resin other than polyvinyl butyral resin, JIS K-6
729 "Polyvinyl formal test method".

The method for producing the polyvinyl acetal resins (a) and (b) is not special. For example, polyvinyl alcohol is dissolved in warm water, and the resulting aqueous solution of polyvinyl alcohol is heated to a temperature of about 0 to 95 ° C. Hold it, add aldehyde in the presence of an acid catalyst, proceed acetalization reaction with stirring, then raise the temperature and age to complete the reaction, then neutralize, wash with water and dry by performing the desired reaction. The polyvinyl acetal resins (a) and (b) can be obtained.

The type of the plasticizer used together with the polyvinyl acetal resins (a) and (b) in the interlayer film according to the first invention is not particularly limited, but monobasic acid ester, polybasic acid ester, etc. The organic plasticizers, the phosphoric acid plasticizers such as the organic phosphoric acid series and the organic phosphorous acid series are listed, and one kind or two or more kinds thereof are preferably used.

The above-mentioned monobasic acid ester plasticizers include
For example, glycols such as triethylene glycol, tetraethylene glycol and tripropylene glycol and butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptanoic acid, n-octylic acid, 2-ethylhexylic acid, pelargonic acid (n-nonyl acid). ), Glycol-based esters obtained by the reaction with an organic acid such as decyl acid, and one or more of these are preferably used.

The polybasic acid ester plasticizer can be obtained, for example, by reacting an organic acid such as adipic acid, sebacic acid or azelaic acid with a linear or branched alcohol having 4 to 8 carbon atoms. Organic acid-based esters are mentioned, and one or more of these are preferably used.

Examples of the phosphoric acid plasticizer include tributoxyethyl phosphate, isodecyl phenyl phosphate, triisopropyl phosphite, etc. One or more of these are preferably used. .

Among the above-mentioned various plasticizers, triethylene glycol-di-2 is more preferably used.
-Ethyl butyrate, triethylene glycol-di-2
-Ethyl hexoate, triethylene glycol dicaproate, triethylene glycol di-n-octoate monobasic acid ester plasticizers and dibasic sebacate, dioctyl azelate, dibutyl carbitol adipate polybasic acid ester systems One or more plasticizers may be used.

The content of the plasticizer is not particularly limited, but is preferably 30 to 70 parts by weight with respect to 100 parts by weight of the polyvinyl acetal resin (a) or (b), Among them, the plasticizer is 30 to 45 parts by weight with respect to 100 parts by weight of the polyvinyl acetal resin (a), and the plasticizer is 35 to 65 parts by weight with respect to 100 parts by weight of the polyvinyl acetal resin (b). More preferably.

When the content of the plasticizer is less than 30 parts by weight based on 100 parts by weight of the polyvinyl acetal resin (a) or (b), the resulting interlayer film has insufficient sound insulation properties and laminated glass penetration resistance. . Conversely, the plasticizer content is 7
If it exceeds 0 parts by weight, the plasticizer bleeds from the obtained intermediate film, and the adhesiveness to glass or synthetic resin layer and the transparency of laminated glass deteriorate.

In addition to the polyvinyl acetal resins (a) and (b) and the plasticizer, the interlayer film according to the first aspect of the present invention may optionally contain an ultraviolet absorber and a light stabilizer as long as the object of the present invention is not impaired. Various additives such as an antioxidant, an adhesion modifier, a surfactant, and a coloring agent may be contained.

The UV absorber is not particularly limited, but is preferably a benzotriazole type, for example, trade names "Tinuvin P", "Tinuvin 320", "Tinuvin 326" manufactured by Ciba-Geigy, “Tinubin 328” and the like are preferably used.

The light stabilizer is not particularly limited, but a hindered amine type is preferable,
For example, the product name “Adeka Stab LA-5” manufactured by Asahi Denka Co., Ltd.
7 "and the like are preferably used.

The above-mentioned antioxidant is not particularly limited, but phenol-based ones are preferable. For example, the product name "Sumilyzer BHT" manufactured by Sumitomo Chemical Co., Ltd.
And Ciba Geigy product name "Irganox 101
0 "and the like are preferably used.

The adhesiveness adjusting agent is not particularly limited, but metal salts of carboxylic acids are preferable, and examples thereof include potassium salts and sodium salts of octylic acid, hexylic acid, butyric acid, acetic acid, formic acid and the like. It is preferably used.

Although the above-mentioned surfactant is not particularly limited, an anionic surfactant is preferable, and for example, sodium lauryl sulfate or sodium alkylbenzene sulfonate is preferably used.

The intermediate film according to the first aspect of the invention comprises a resin film (A) formed by forming a polyvinyl acetal resin (a) and a plasticized polyvinyl acetal resin containing a plasticizer as an essential component, and a polyvinyl acetal resin (b). And a resin film (B) formed by forming a plasticized polyvinyl acetal resin containing a plasticizer as an essential component at least 2
It is obtained by stacking layers.

The above resin film (A) imparts excellent adhesiveness, weather resistance, durability, workability and the like to the obtained intermediate film, and the above resin film (B) provides excellent sound insulation to the obtained intermediate film. Imparts sex. Further, since there is almost no difference in viscoelastic behavior such as viscosity between the resin film (A) and the resin film (B), a minute disturbance may occur at the laminating interface when laminating or forming laminated glass. None, the resulting laminated glass does not generate optical distortion.

The method for forming the resin film (A) or (B) is not particularly limited, and the polyvinyl acetal resin (a) or (b), the plasticizer, and other additives as necessary may be added. The mixture may be uniformly kneaded and then extruded, calendered, or press-molded by a conventionally known method of forming a film into a sheet.

The film thickness of the resin films (A) and (B) is not particularly limited, but both are 0.05.
It is preferably at least mm. When the film thickness of either the resin film (A) or (B) is less than 0.05 mm,
It becomes difficult to obtain excellent sound insulation and weather resistance.

In the first invention, the method for obtaining the intermediate film by laminating at least two layers of the resin film (A) and the resin film (B) is not particularly limited, and the resin formed separately is used. The film (A) and the resin film (B) may be laminated by heating and pressurizing to form an intermediate film, or the resin film (A) and the resin film (B) may be integrally formed simultaneously by a multi-layer extrusion molding method. It may be laminated as an intermediate film. When the laminated glass according to the second invention is obtained, the resin film (A) and the resin film (B), which are separately formed, are placed between at least a pair of glass and / or synthetic resin layers, and heated. An intermediate film may be formed by laminating simultaneously with the production of laminated glass by applying pressure.

The laminated structure of the resin film (A) and the resin film (B) in the intermediate film is not particularly limited, but for example, a two-layer laminated structure of resin film (A) / resin film (B) Structure, three-layer laminated structure of resin film (A) / resin film (B) / resin film (A) or resin film (B) / resin film (A) / resin film (B), resin film (A) / resin Membrane (B) / Resin membrane (A) /
Any of a laminated structure of four or more layers such as the resin film (B) may be used.

Further, in the multi-layered laminated structure of three or more layers, resin film (A) / resin film (A) / resin film (B), resin film (A)
/ Resin film (B) / resin film (B), resin film (A) / resin film (A) / resin film (B) / resin film (B), etc., including a laminated structure of the same kind of resin film It may have a laminated structure.

Furthermore, the resin film (A) and the resin film (B) may be laminated via a film that does not permeate the plasticizer, for example, a polyethylene terephthalate film that is undecorated or is decoratively printed.

The laminated structure in the case of laminating via the above film is, for example, a three-layer laminated structure of resin film (A) / film / resin film (B), resin film (A) / film / resin film (A) It may have a laminated structure of four or more layers such as / resin film (B) or resin film (B) / resin film (A) / film / resin film (B).

The intermediate film according to the first aspect of the present invention may have any of the above-mentioned laminated structures, but in particular, the laminated structure is such that the resin film (A) is arranged as the outermost layer on both surfaces of the intermediate film. Is more preferable. By arranging the resin film (A) on the outermost layers on both sides of the intermediate film, the adhesiveness with the glass or the synthetic resin layer, the weather resistance and the like are further improved, and the workability in producing the laminated glass is also the usual one. This is equivalent to using a polyvinyl butyral resin-based interlayer film, and existing laminated glass manufacturing technology and manufacturing equipment can be used as is.

The thicker the intermediate film is, the more the sound insulation is improved, but practically, the thickness is 0.3 to 1.6 mm, which is the same as the thickness of a normal intermediate film for laminated glass. Is preferred.

The laminated glass according to the second invention is produced by bonding at least a pair of glass and / or synthetic resin layers with the intermediate film according to the first invention.

The structure of the laminated glass is not particularly limited, and for example, glass / interlayer film of the first invention /
It may have a three-layer structure of glass, glass / intermediate film / synthetic resin layer of the first invention, synthetic resin layer / intermediate film / synthetic resin layer of the first invention, or a multilayer similar to these structures. It may be configured.

The type of the above glass is not particularly limited, and various types of inorganic glass such as float plate glass, polished plate glass, flat plate glass, curved plate glass, flat plate glass, template glass, wire mesh type template glass, colored glass, etc. And organic glass, and one or more of these are preferably used. The thickness of the glass is not particularly limited as long as it is appropriately selected depending on the application.

The synthetic resin layer is not particularly limited, and examples thereof include synthetic resins having excellent transparency such as polyethylene terephthalate resin, polybutylene terephthalate resin, polymethylmethacrylate resin, polycarbonate resin, and polyvinylidene chloride resin. The plate-shaped body, the film or the sheet, and the like, and one kind or two or more kinds thereof are preferably used. The thickness of the synthetic resin layer is not particularly limited as long as it is appropriately selected depending on the application. When the layer adhered by the intermediate film according to the first invention is only a synthetic resin layer, at least one of the synthetic resin layers needs to have a certain rigidity.

The method for producing the laminated glass is not special, and for example, the intermediate film or the resin film (A) and the resin film (B) are sandwiched between two transparent glass plates, and this is made of rubber. After pre-bonding in a bag while sucking and degassing under reduced pressure at a temperature of about 70 to 110 ° C., using an autoclave or a press, a temperature of about 120 to 150 ° C. and a temperature of about 10 to 15 kg / cm ² . A desired laminated glass can be obtained by heating and pressurizing with pressure to perform the main bonding.

[0054]

The intermediate film according to the first invention has an average degree of polymerization of 100.
A resin film (A) containing as a main component a polyvinyl acetal resin (a) obtained by acetalizing polyvinyl alcohol having a saponification degree of 0 or more and less than 2000 and a saponification degree of 96 mol% or more with an aldehyde having 4 to 10 carbon atoms; The average degree of polymerization is 2000 to 3000 and the degree of saponification is 70 to 92 mol%.
Is formed by laminating two or more layers of a resin film (B) containing a polyvinyl acetal resin (b) as a main component, which is obtained by acetalizing polyvinyl alcohol with an aldehyde having 4 to 10 carbon atoms. Due to the internal frictional effect between A) and the resin film (B), sound energy is effectively converted into heat energy and absorbed, and in particular, a decrease in sound insulation due to the coincidence effect in the middle and high range of 2000 Hz is prevented.

Further, since there is almost no difference in viscoelastic behavior between the resin film (A) and the resin film (B), a minute disturbance of the laminating interface when laminating or forming a laminated glass is prevented, No optical distortion.

[0056]

EXAMPLES In order to explain the present invention in more detail, examples will be given below.

(Example 1)

( 1) Preparation of polyvinyl acetal resin In 2910 g of pure water, an average degree of polymerization of 1700 and a degree of saponification of 99.
After 281 g of 1 mol% polyvinyl alcohol was added and dissolved by heating, the liquid temperature was adjusted to 12 ° C., 148 g of n-butyraldehyde having 4 carbon atoms and 20% of 35% hydrochloric acid as a catalyst.
1 g was added and the reaction temperature was kept at 12 ° C. to precipitate the reaction product. Then, after raising the liquid temperature to 45 ° C. and holding for 3 hours to complete the reaction, washing with excess water to wash off unreacted n-butyraldehyde, neutralization of the hydrochloric acid catalyst, washing with water and drying. Then, a white powdery polyvinyl butyral resin (a) was obtained. The obtained polyvinyl butyral resin (a) had a butyralization degree of 65.5 mol% and a vinyl acetate component of 0.9 mol%.

The average degree of polymerization of 200 was added to 2890 g of pure water.
0, polyvinyl alcohol 27 having a saponification degree of 88.2 mol%
After adding 5 g and dissolving by heating, adjust the liquid temperature to 12 ° C,
148 g of n-butyraldehyde and 201 g of 35% hydrochloric acid as a catalyst were added, and the liquid temperature was kept at 12 ° C. to precipitate the reaction product. Then, the liquid temperature was raised to 45 ° C. and maintained for 3 hours to complete the reaction, and then washed with excess water to remove unreacted n-
Butyraldehyde was washed off, the hydrochloric acid catalyst was neutralized, washed with water and dried to obtain a white powdery polyvinyl butyral resin (b). The obtained polyvinyl butyral resin (b) had a butyralization degree of 60.0 mol% and a vinyl acetate component of 11.8 mol%.

( 2) Preparation of resin film Polyvinyl butyral resin (a) 100 obtained above
As a plasticizer, triethylene glycol-
After mixing 40 parts by weight of di-2-ethylbutyrate and sufficiently melting and kneading with a mixing roll, press molding is performed at 150 ° C. for 30 minutes using a press molding machine to obtain a thickness of 0.2 mm.
A resin film (A) was obtained.

In addition, 100 parts by weight of the polyvinyl butyral resin (b) obtained above was mixed with 40 parts by weight of triethylene glycol-di-2-ethylbutyrate as a plasticizer, and the same method as above was used. A resin film (B) having a thickness of 0.2 mm was obtained.

( 3) Preparation of Intermediate Film and Laminated Glass The resin films (A) and (B) obtained above are laminated in the order of resin film (A) / resin film (B) / resin film (A). In total, 2 pieces of transparent float glass (length 30 cm x width 3)
0 cm × thickness 3 mm), put this in a rubber bag, and degas for 20 minutes at a vacuum degree of 20 mmHg,
Move to 90 ° C oven with degassing, 90 ° C
The laminated glass was pre-bonded by vacuum pressing while holding for 30 minutes.

Next, the pre-bonded laminated glass was put into an air type autoclave, and main bonding was carried out for 20 minutes under the conditions of a temperature of 135 ° C. and a pressure of 12 kg / cm ² to simultaneously produce an interlayer film and a laminated glass. The thickness of the obtained interlayer film was 0.6 mm.

( 4) Evaluation The sound insulation and optical distortion of the laminated glass obtained above were evaluated by the following methods. The evaluation results are as shown in Table 1.

Sound insulation : A sample was cut out from the laminated glass obtained above, and this sample was vibrated by a vibration exciter (trade name "G21-005D", manufactured by Shaken Co., Ltd.) for a damping test, and obtained from there. The vibration characteristics obtained were amplified by a mechanical impedance amplifier (trade name "XG-81", manufactured by Rion), and the vibration spectrum was analyzed by an FFT analyzer (trade name "FFT analyzer HP3582A", manufactured by Yokogawa Hewlett Packard). . From the ratio of the loss factor thus obtained and the resonance frequency with glass, 20
A graph showing the relationship between the sound frequency (Hz) and the sound transmission loss (dB) at ° C was created, and the minimum sound transmission loss (TL value) near the sound frequency of 2000 Hz was obtained. The sound insulation of the laminated glass was judged by setting the acceptance standard of sound insulation to be a TL value of 35 or more.

Optical distortion : An object in front was seen through a laminated glass, and the degree of distortion of the object was visually observed. When no distortion was observed, it was evaluated as good, and when distortion was recognized, it was evaluated as defective.

(Examples 2 to 4, Comparative Examples 1 to 4)

Polyvinyl acetal resins (a) and (b) were prepared in the same manner as in Example 1 using polyvinyl alcohol and aldehydes of the types shown in Table 1, and Table 1
Resin films (A) and (B) were produced in the same manner as in Example 1 with the amount of plasticizer and the film thickness as shown in FIG.

Then, using the resin films (A) and (B) obtained above, an interlayer film and a laminated glass were simultaneously prepared in the same manner as in Example 1 with the laminated constitution and film thickness shown in Table 1. .

Sound insulation of the obtained laminated glass, and
The optical distortion was evaluated in the same manner as in Example 1 and the results are shown in Table 1.
It was as shown in.

[0071]

[Table 1]

[0072]

As described above, the laminated glass according to the second invention produced by using the interlayer film according to the first invention is
It is excellent in sound insulation and does not generate optical distortion, and is suitable for use as a sound insulation laminated glass mainly for construction.

Claims (2)

[Claims] 1. A laminated resin film which is formed by laminating two kinds of resin films and has a layered structure of at least two layers, wherein one resin film (A) has an average degree of polymerization of 1,000 or more and less than 2,000. A film is formed of a plasticized polyvinyl acetal resin containing a polyvinyl acetal resin (a) obtained by acetalizing polyvinyl alcohol having a saponification degree of 96 mol% or more with an aldehyde having 4 to 10 carbon atoms and a plasticizer. , The other resin film (B) has an average degree of polymerization of 200.
A plasticized polyvinyl acetal resin containing a polyvinyl acetal resin (b) obtained by acetalizing polyvinyl alcohol having a saponification degree of 0 to 3000 and a saponification degree of 70 to 92 mol% with an aldehyde having 4 to 10 carbon atoms and a plasticizer. An intermediate film for laminated glass, characterized in that 2. A laminated glass characterized in that at least a pair of glass and / or synthetic resin layers are adhered by the interlayer film according to claim 1.