JPH11171604A - Interlayer for laminated glass and laminated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an interlayer for laminated glass that is excellent in heat insulation, inexpensive and high in transparency and shows good adhesions on the interfaces between the glass plates and the interlayer and between the interlayer by forming both outer layers with plasticized polyvinyl acetal resin films and the interlayer with a heat-insulating plasticized polyvinyl acetal resin film. SOLUTION: A plasticized polyvinyl acetal resin prepared by acetalizing polyvinyl alcohol with a 3-6C aldehyde and a plasticizer are mixed and the composition is used for both outer layers. The polyvinyl alcohol for acetalization has preferably an average degree of polymerization of 500-3,000. The heat- insulating plasticized polyvinyl acetal resin is prepared by adding a near infrared ray-absorbing agent to the polyacetal resin film or by boring fine foams in the plasticized polyvinyl acetal resin film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interlayer film for laminated glass having good transparency and heat insulation, and a laminated glass using the same.

[0002]

2. Description of the Related Art Conventionally, laminated glass in which an interlayer film is sandwiched between transparent glass plates is safe without breaking glass plate fragments even if it is damaged by an external impact. Widely used for window glass of buildings and the like. As such an intermediate film, a polyvinyl butyral resin plasticized with a plasticizer is used. However, such laminated glass is excellent in safety without breaking glass fragments when broken,
There was a problem that it was inferior in heat insulation.

[0003] Among rays, infrared rays having a wavelength of 780 nm or more have an energy amount of about 10 times as compared with ultraviolet rays.
Although it is as small as about%, it is called a hot wire because it has a large thermal effect and is released as heat when absorbed by a substance, causing a rise in temperature. Therefore, the heat insulation can be improved by blocking the infrared rays entering from the window glass and suppressing the temperature rise of the vehicle or the building. As such a glass plate, for example, a hot-cut glass is commercially available.

[0004] The above-mentioned heat ray cut glass is provided with a multi-layer coating of metal / metal oxide on the surface of a glass plate by metal deposition, sputtering, or the like for the purpose of blocking direct sunlight. However, this multilayer coating is vulnerable to external abrasion and has poor chemical resistance. For example, it was necessary to laminate a plasticized polyvinyl butyral resin interlayer on the surface to form a laminated glass.

[0005] However, the heat ray cut glass in which the plasticized polyvinyl butyral resin interlayer is laminated on the surface described above is (a) expensive and (ii) the multilayer coating is thick, so that the transparency (visible light transmittance) is reduced. (C) The adhesiveness between the multilayer coating and the intermediate film is lowered, and peeling and whitening of the intermediate film occur.

As a solution to such a problem, for example, a laminated glass in which a metallized polyester film is laminated between plasticized polyvinyl butyral resin sheets has been proposed (Japanese Patent Publication No. Sho 61-52093,
JP-A-64-36442, etc.). However, this laminated glass has a problem in adhesion between the plasticized polyvinyl butyral resin sheet and the polyester film, and has problems such as peeling off at the interface.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide excellent heat insulating properties, low cost, good transparency, adhesion at the interface between a glass plate and an intermediate film, and an intermediate film. An object of the present invention is to provide an interlayer film for laminated glass having good adhesion at an interface and a laminated glass using the same.

[0008]

Means for Solving the Problems The interlayer film for laminated glass of the present invention is an interlayer film for laminated glass comprising at least three resin film laminates having outer layers provided on both surfaces of the intermediate layer. Both outer layers are formed from a polyvinyl acetal resin obtained by acetalizing polyvinyl alcohol with an aldehyde having 3 to 6 carbon atoms and a plasticized polyvinyl acetal resin film comprising a plasticizer, and the intermediate layer has a heat insulating property. It is characterized by being formed from a film.

Hereinafter, the present invention will be described. The polyvinyl acetal resin used in the present invention is obtained by acetalizing polyvinyl alcohol with an aldehyde.

The polyvinyl alcohol used in the polyvinyl acetal resin has an average polymerization degree of 500 to 500.
3,000 is preferred, and more preferably an average degree of polymerization of 1,
2,000 to 2,500. If the average degree of polymerization is less than 500, the penetration resistance may be reduced when laminated glass is used, and if it exceeds 3,000, molding of the resin film becomes difficult, and the strength of the resin film may be too strong. Therefore, it is not preferable.

When the number of carbon atoms of the aldehyde is 2 or less, the moldability of the resin film deteriorates, and when the number of carbon atoms is 7 or more, the reactivity of acetalization decreases. 3 carbon atoms
Examples of the aldehydes of to 6 include propionaldehyde, n-butyraldehyde, isobutyraldehyde,
Examples thereof include n-pentylaldehyde and n-hexylaldehyde, which may be used alone or in combination of two or more.

The polyvinyl acetal resin is preferably obtained by acetalization with n-butyraldehyde having 4 carbon atoms. By using a polyvinyl acetal resin acetalized with n-butyraldehyde having 4 carbon atoms, the adhesive strength of the resin film is increased,
The weather resistance is improved, and the production of the resin is facilitated.

The polyvinyl acetal resin can be produced by a conventionally known method. For example, an aqueous solution of polyvinyl alcohol dissolved in warm water is maintained at a predetermined temperature (0 to 95 ° C.), and then an acid catalyst and an aldehyde are removed. In addition, the acetalization reaction proceeds with stirring. Then, after raising the reaction temperature to complete the reaction, neutralization, washing with water and drying are performed, whereby a powder of a polyvinyl acetal resin can be obtained.

The degree of acetalization of the polyvinyl acetal resin is preferably 40 mol% or more, more preferably 50 mol% or more, because the lower the degree of acetalization, the lower the compatibility with the plasticizer.

The polyvinyl acetal resin is composed of a vinyl acetal component and a vinyl alcohol component, and the amounts of these components are, for example, JIS K67.
28 "Polyvinyl butyral test method".

After the polyvinyl acetal resin prepared as described above is blended with a predetermined plasticizer, the plasticized polyvinyl acetal resin is formed into a sheet by a molding method such as extrusion molding, calender molding, or press molding. A membrane can be obtained.

The plasticizer is not particularly limited as long as it is generally used for an interlayer film for laminated glass. For example, organic plasticizers such as monobasic acid ester and polybasic acid ester; And a phosphoric acid plasticizer such as an organic phosphorous acid.

The monobasic acid ester includes, for example,
Triethylene glycol, butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptanoic acid, n-octylic acid,
-Ethylhexylic acid, pelargonic acid (n-nonylic acid),
Glycol esters obtained by reaction with an organic acid such as decyl acid are preferred. In addition to the above, esters obtained by reacting tetraethylene glycol or tripropylene glycol with the above organic acid can also be used.

As the polybasic acid ester, for example,
Organic acids such as adipic acid, sebacic acid, azelaic acid,
Esters obtained by reaction with a linear or branched alcohol having 4 to 8 carbon atoms are mentioned. Examples of the phosphate plasticizer include tributoxyethyl phosphate, isodecylphenyl phosphate, and triisopropyl phosphate.

Among the above plasticizers, triethylene glycol di-2-ethyl butyrate, triethylene glycol di-2-ethylhexoate, triethylene glycol di-caprylate, triethylene glycol In addition to di-n-octoate, dibutyl sebacate,
Dioctyl azelate, dibutyl carbitol adipate and the like are preferably used. These may be used alone or in combination of two or more.

If the amount of the plasticizer in the polyvinyl acetal resin is too small, the penetration resistance may be reduced. If the amount is too large, the transparency of the laminated glass obtained by bleed-out and the adhesion to the glass plate may be reduced. Therefore, the amount is preferably 25 to 55 parts by weight, more preferably 3 to 55 parts by weight, based on 100 parts by weight of the polyvinyl acetal resin.
0 to 45 parts by weight.

As a method of imparting heat insulation to the plasticized polyvinyl acetal resin film, for example, the following methods (1) and (2) are used. (1) A method in which a near-infrared absorbing agent is contained in a plasticized polyvinyl acetal resin film. Examples of the near-infrared absorbing agent include metal oxides such as tin-doped indium oxide (ITO) and tin-doped antimony oxide (ATO); complexes of phthalocyanine, dithiol, dithiobenzoin, and the like with a metal.

The compounding amount of the above-mentioned near-infrared absorbing agent is 0.0 to 100 parts by weight of the plasticized polyvinyl acetal resin.
05 to 10 parts by weight, more preferably 0.01 to 10 parts by weight.
１1 part by weight. If the amount is less than 0.005 parts by weight, the effect of absorbing near-infrared rays may be difficult to obtain, and if it exceeds 10 parts by weight, the transmittance of visible light may be reduced.

(2) In this method, fine bubbles are generated in the plasticized polyvinyl acetal resin film. Means for generating fine bubbles include, for example, a method of foaming in a supercritical fluid. Specifically, USP44
As described in U.S. Pat. No. 73665, by dissolving carbon dioxide in a plasticized polyvinyl acetal resin under high pressure and foaming it during extrusion molding, bubbles having a particle size of 0.01 μm or less are generated, and transparency and heat insulation are obtained. To obtain a plasticized polyvinyl acetal resin film having both properties.

The interlayer film for laminated glass of the present invention may contain, if necessary, an ultraviolet absorber, a light stabilizer, an antioxidant, an adhesion regulator, a surfactant, a colorant, etc., to produce a polyvinyl acetal resin. In the process or in the process of mixing the polyvinyl acetal resin and the plasticizer, it may be appropriately added.

As the above-mentioned ultraviolet absorber, for example, 2-
(2′-hydroxy-5′-methylphenyl) benzotriazole (manufactured by Ciba Geigy, trade name: Tinuvin P), 2- (2′-hydroxy-3 ′, 5′-di-t-)
Butylphenyl) benzotriazole (trade name: Tinuvin 320, manufactured by Ciba Geigy), 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5
Chlorobenzotriazole (manufactured by Ciba Geigy, trade name: Tinuvin 326), 2- (2′-hydroxy-
Benzotriazoles such as 3 ', 5'-di-amylphenyl) benzotriazole (trade name; Tinuvin 328, manufactured by Ciba Geigy) can be used. Further, as the light stabilizer, as a hindered amine-based, for example,
Asahi Denka Co., Ltd., trade name: ADK STAB LA-57.

Examples of the antioxidant include phenol-based ones, for example, Sumitomo Chemical Co., Ltd., trade name: Sumilizer BHT, Ciba-Geigy Co., trade name: Irganox 1010. Examples of the adhesive force adjuster include metal salts of carboxylic acids, that is, octylic acid,
And potassium salts of hexyl acid, butyric acid, formic acid and the like. Examples of the surfactant include sodium laurate and alkylbenzene sulfonic acid.

The interlayer film for laminated glass of the present invention can be produced, for example, as follows. The plasticized polyvinyl acetal resin (hereinafter, a resin film using the resin is referred to as a resin film A) and a heat-insulating plasticized polyvinyl acetal resin (hereinafter, a resin film using the resin is referred to as a resin film B). By a multilayer extrusion method, for example,
A method of integrally molding a resin film A / resin film B / resin film A (in the case of a three-layer laminate), a method of separately molding the resin film A and the resin film B, and two glass plates. And a method of integrating them by heating and pressurizing them in between, and simultaneously laminating them in a resin film A / resin film B / resin film A configuration (in the case of a three-layer laminate) at the time of manufacturing a laminated glass.

Using the interlayer film for laminated glass of the present invention,
As a method for manufacturing laminated glass,
For example, two transparent glass plates
A laminated body in the order of resin film A / resin film B / resin film A,
Alternatively, the resin film A and the resin film B are formed as a resin film A / resin film B / resin film.
After sandwiching it so as to have a laminated configuration in the order of A,
Put it in a rubber bag and vacuum-suction at 70-110 ° C
Pre-adhesion, then use autoclave or press
120-150 ° C, 10-15 kg / cm ^TwoHeating
By performing final bonding under pressure, transparent
You can get a lath.

The interlayer film for laminated glass of the present invention is a resin film A / resin film B / resin film A other than the three-layer laminate.
It may be a five-layer laminate of / resin film B / resin film A / resin film B / resin film A, or a multilayer laminate of six or more layers. Further, the resin film A and the resin film B are respectively a laminate of resin films of the same type, a resin film A / a resin film A, and a resin film B.
/ A two-layer laminate of the resin film B may be used.

The thickness of the interlayer film for a laminated glass is 0.1 mm.
3-1.6 mm is preferred.

The interlayer film for laminated glass according to the present invention has an excellent adhesive property on both sides of an intermediate layer composed of a transparent and heat-insulating resin film. It is transparent, has excellent heat insulating properties, and has good adhesiveness, so that it does not peel off.

[0032]

Next, embodiments of the present invention will be described.

281 g of polyvinyl alcohol having an average degree of polymerization of 1700 was added to 2910 g of synthetic pure water of polyvinyl acetal resin and dissolved by heating. Next, after the temperature of the solution was adjusted to 12 ° C., 201 g of 35% by weight hydrochloric acid catalyst and 148 g of n-butyraldehyde were added, and the temperature was maintained to precipitate a reaction product. Next, after raising the temperature of the reaction system to 45 ° C. and holding it for 3 hours to complete the reaction,
Unreacted n-butyraldehyde was washed out by washing with excess water, and the hydrochloric acid catalyst was neutralized. Next, through washing with water and drying, a polyvinyl acetal resin in the form of a white powder was obtained.
The degree of acetalization of the obtained polyvinyl acetal resin was 65.5 mol%.

Example 1 100 parts by weight of the obtained polyvinyl acetal resin, 40 parts by weight of triethylene glycol di-2-ethyl butyrate as a plasticizer, and 2- (2'-hydroxy-5) as an ultraviolet absorber 0.2 parts by weight of '-methylphenyl) benzotriazole (trade name; Tinuvin P, manufactured by Ciba Geigy) was mixed to obtain a plasticized polyvinyl acetal resin (hereinafter, referred to as resin C).
The resin C was sufficiently melt-kneaded with a mixing roll, and then press-formed at 150 ° C. for 30 minutes using a press forming machine to obtain a resin film A ₁ having a thickness of 0.3 mm.

Further, tin-doped indium oxide powder (manufactured by Mitsubishi Materials Corporation, particle size 0.03%) was added to 100 parts by weight of resin C.
After adding 0.2 parts by weight of the mixture, the mixture was sufficiently melt-kneaded with a mixing roll, and then 150 ° C.
Press molding for 30 minutes, thickness 0.16 with heat insulation
to obtain a resin film B ₁ of mm.

Using the resin film A ₁ and the resin film B ₁ , the resin film A ₁ / resin film B ₁ / resin film A ₁ are superposed in this order, and transparent float glass (30 mm × 30 m
mx 3 mm thick) and put it in a rubber bag.
After degassing for 20 minutes at a vacuum of 0 torr, the sample was kept at 90 ° C. for 30 minutes while maintaining the degassed state, and pre-bonded by vacuum pressing. Next, the laminated glass obtained by the preliminary bonding was put into an air type autoclave, and the pressure was 12 kg / c.
The main bonding was performed by heating and pressurizing under conditions of m ² and a temperature of 135 ° C. for 20 minutes, and an intermediate film (three-layer laminate) and a transparent laminated glass were simultaneously produced.

(Example 2) Resin film A obtained in Example 1
₁ , after injecting carbon dioxide at -20 ° C. and a pressure of 50 kg / cm ² for 5 hours, put into an oil bath at 80 ° C., and deposit a 0.16 mm thick resin film B ₂ having bubbles with an average particle diameter of 0.006 μm. Obtained. In place of the resin film B _1, except for using the resin film B _2, to obtain a laminated glass in the same manner as in Example 1.

(Comparative Example 1)
To obtain a resin film A ₂ of 76mm thickness. Instead of the intermediate film (three-layer laminate) composed of the resin film A ₁ and the resin film B ₁ ,
_A laminated glass was obtained in the same manner as in Example 1, except that only ₂ was used alone.

(Comparative Example 2)
To obtain a resin film A ₂ of 76mm thickness. Next, the float glass used in Example 1 was opposed to the float glass in which tin-doped indium oxide was vapor-deposited on the glass surface such that the vapor deposition surface was on the inside, and an intermediate film (resin film A ₁ and resin film B ₁ ) was formed. instead of the three-layer laminate), except for using only the resin film a ₂ alone, to obtain a laminated glass in the same manner as in example 1.

With respect to the resin film and the laminated glass obtained above, the following items were evaluated for performance, and the results are shown in Table 1. (1) Adhesive strength (peeling strength) test A transparent float glass was used on one side, a polyethylene terephthalate (PET) film was used on the other side, and an intermediate film immediately after the production was sandwiched between the two. Bonded under similar conditions, glass / interlayer / P
A laminate of the ET film was obtained. This laminate is 2 mm wide x
The test piece was cut to a length of 100 mm, and the intermediate film at one end of the test piece was peeled off. Using a tensile tester so as to peel off the end of the peeled interlayer film, a pulling speed of 50 c
A 90 degree peel test was performed at m / min, and the 90 degree peel strength was measured. The test was performed with n = 10.

(2) Insulation test A heat insulation box having an opening of 30 cm × 30 cm and having a length of 40 cm on a side filled with styrene foam was prepared.
m of laminated glass was attached. Then, put the insulation box in 40
Infrared heater (Yanagimoto Kogyo Co., Ltd. “DI-9
7 ", 1.5 KW) for 2 hours, and the change in the internal temperature of the heat insulating box was measured.

(3) Light Transmittance Test The transmittance of visible light and near-ultraviolet light of the laminated glass was measured using a direct spectrophotometer (“UV3100” manufactured by Shimadzu Corporation).

[0043]

[Table 1]

[0044]

The interlayer film for laminated glass and the laminated glass of the present invention have the above-mentioned constitutions, and are excellent in transparency, heat insulation and adhesion.
It is suitably used as a window glass for vehicles.

Claims (2)

[Claims] 1. An intermediate film for laminated glass comprising at least three resin film laminates having outer layers provided on both surfaces of an intermediate layer, wherein at least both outer layers are formed by converting polyvinyl alcohol to an aldehyde having 3 to 6 carbon atoms. For a laminated glass, characterized by being formed from a plasticized polyvinyl acetal resin film comprising a polyvinyl acetal resin obtained by acetalization and a plasticizer, and wherein the intermediate layer is formed from a plasticized polyvinyl acetal resin film having heat insulating properties. Interlayer. 2. A laminated glass, wherein two transparent glass plates are bonded via the interlayer for laminated glass according to claim 1.