JP2004123423A - Thermoplastic resin sheet, laminated product of the same, and laminated glass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic resin sheet for laminated glass, from which the laminated glass exhibiting excellent resistance to penetration not only at ordinary temperature but also at high temperatures can be obtained when the thermoplastic resin sheet is used as an interlayer film of the laminated glass, a laminated product using the same, and the laminated glass. <P>SOLUTION: The thermoplastic resin sheet is a laminated sheet in which surface layers are laminated on the both surfaces of an inner layer. At least one layer of the surface layers is formed from a layer (A) comprising a poly(vinyl butyral) resin and a plasticizer, and the inner layer is formed from a layer (B) comprising the poly(vinyl butyral) resin and the plasticizer. The storage modulus (G') of the layer (A) is set so as to be larger than that of the layer (B). <P>COPYRIGHT: (C)2004,JPO

Description

【００３３】
実施例１及び２の合わせガラスは、比較例１〜３に比べて耐貫通性が優れる。比較例１は単層膜であり、比較例２は表層と内層のＧ’　が同一であるため、オートクレーブ内で均一層になる（比較例１と同様になる）。
比較例３は表層のＧ’　＞内層のＧ’　であるが、樹脂構造が同一であるため、オートクレーブで「単に可塑剤部数の少ない」均一層になる。
【００３４】
【発明の効果】
本発明の熱可塑性樹脂シートは、上述の構成となされているので、合わせガラス用中間膜として好適に使用することができ、透明性、耐候性、接着性等の合わせガラスに必要な基本性能や合わせガラス加工性が優れると共に、積層体として得られる合わせガラスは常温のみならず高温において優れた耐貫通性能を発現し、且つ光学歪みが少ない。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a thermoplastic resin sheet, a laminate thereof, and a laminated glass, and more particularly, to a thermoplastic resin sheet used for an interlayer film for a laminated glass, a laminate using the thermoplastic resin sheet, and a laminated glass.
[0002]
[Prior art]
In general, a laminated glass in which an interlayer film made of a plasticized polyvinyl butyral resin is interposed between a pair of glass plates has excellent transparency, weather resistance and adhesiveness, and has excellent safety without breaking glass fragments when broken. Therefore, it is widely used, for example, as a window glass of a traffic vehicle such as an automobile or a window glass of a building.
[0003]
In recent years, the diversification of laminated glass has progressed, and it has been widely required to improve the added value of laminated glass, such as decorativeness, heat insulation properties, laminated workability, and penetration resistance. For this reason, it is difficult to satisfy all the required items only with an intermediate film made of a single material, and instead of a single-layer intermediate film made of a single resin film, a multilayer intermediate film made of a multilayer resin film has been receiving attention.
[0004]
Among these, as means for improving the penetration resistance, for example, Patent Document 1 and Patent Document 2 disclose the penetration resistance by laminating a plurality of polyvinyl butyral resins having different structures or intermediate films having different numbers of plasticizer parts. It is reported that it can be improved. However, according to these methods, the workability is reduced by laminating a plurality of sheets together with the glass, and optical distortion caused by poor smoothness of the interface between the interlayer films and the like, an image viewed through the combined glass. There were problems such as distortion.
[0005]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 3-124440 [Patent Document 2]
JP-A-3-124441 [0006]
Patent Document 3 proposes a method of improving the impact resistance by changing the hardness of the intermediate film of each layer by changing the amount of the plasticizer between the surface layer and the inner layer in the intermediate film composed of a laminated film. Have been.
However, in this method, when a polyvinyl butyral resin having the same structure is used, in order to improve the appearance of the laminated glass, in an autoclave treatment performed under high-temperature and high-pressure conditions, a uniform single-layer film is formed instead of a multilayer film. Therefore, there is a problem that the improvement of the penetration resistance cannot be achieved.
[0007]
[Patent Document 3]
JP-A-5-85782
Further, when a resin different in type from polyvinyl butyral resin such as polyethylene terephthalate or polycarbonate is used, the characteristics of the resin are different, so that a high temperature is required at the time of producing a laminated glass, and there is a problem that energy efficiency is deteriorated. Further, increasing the thickness of the intermediate film is also effective for improving the penetration resistance. However, in this method, the weight of the laminated glass is increased, so that the fuel efficiency of the automobile is deteriorated, and the handleability of the laminated glass is deteriorated. There was a problem.
[0009]
[Problems to be solved by the invention]
The present invention has been made in view of the above-mentioned drawbacks, and an object thereof is that when used as an interlayer film for laminated glass, the resulting laminated glass can exhibit excellent penetration resistance not only at room temperature but also at high temperatures. An object of the present invention is to provide a thermoplastic resin sheet, a laminate using the thermoplastic resin sheet, and a laminated glass.
[0010]
[Means for Solving the Problems]
The thermoplastic resin sheet of the present invention is a thermoplastic resin sheet composed of a laminated sheet having a surface layer laminated on both surfaces of an inner layer, wherein at least one surface layer is formed of a layer (A) composed of a polyvinyl butyral resin and a plasticizer. The inner layer is formed of a layer (B) composed of a polyvinyl butyral resin and a plasticizer, and the storage elastic modulus (G ′) of the layer (A) measured at 40 ° C. and 10 rad / sec is larger than that of the layer (B). It is characterized in that:
[0011]
Hereinafter, the present invention will be described in detail.
The polyvinyl butyral resin (hereinafter, referred to as PVB) used in the present invention uses polyvinyl alcohol (hereinafter, referred to as PVA) as a raw material.
The average degree of polymerization of the PVA is preferably in the range of 500 to 3,000, more preferably 1,000 to 2,500.
When the average degree of polymerization of PVA is less than 500, the penetration resistance of a laminated glass obtained by using a thermoplastic resin sheet as an interlayer for laminated glass may decrease, and when it exceeds 3,000, extrudability is extremely poor. In some cases, the strength of the thermoplastic resin sheet becomes too large to be used as an interlayer for laminated glass.
[0012]
The butyralization degree of the PVB is preferably 40 to 70 mol%.
If the degree of butyralization is less than 40 mol%, the compatibility with the plasticizer becomes poor and the plasticizer bleeds out, so that adverse effects such as a decrease in the adhesive strength between the thermoplastic resin sheet intermediate film and the glass are exhibited. Sometimes. On the other hand, when the butyralization degree exceeds 70 mol%, the thermoplastic resin sheet intermediate film becomes soft and may not exhibit sufficient penetration resistance.
[0013]
As the plasticizer, those conventionally used for interlayer films for laminated glass can be used. For example, triethylene glycol di-2-ethylbutyrate (3GH), triethylene glycol di-2-ethylhexa. Noate (3GO), triethylene glycol di-2-capryate, and the like. These may be used alone or in combination of two or more.
[0014]
The blending amount of the plasticizer is preferably 30 to 50 parts by weight based on 100 parts by weight of PVB. If the amount of the plasticizer is less than 30 parts by weight, the plasticizing effect of PVB is insufficient and molding becomes difficult, and if it exceeds 50 parts by weight, the compatibility is reduced and the plasticizer may be separated.
[0015]
To the PVB, a metal carboxylate, modified silicone oil, or the like can be added for the purpose of adjusting the adhesive strength between the thermoplastic resin sheet interlayer and the glass.
As the metal carboxylate, an alkali metal salt or an alkaline earth metal salt of an aliphatic monocarboxylic acid or an aliphatic dicarboxylic acid having 12 or less carbon atoms is preferable, and as a metal component, a carboxylic acid such as Mg, Na, or K is used. Include acetic acid, propionic acid, butyric acid, caproic acid, caprylic acid and the like.
Examples of the preferred metal carboxylate include potassium acetate, magnesium acetate, potassium propionate, magnesium propionate and the like, and among them, potassium acetate and magnesium acetate are more preferred.
[0016]
Examples of the modified silicone oil include ether-modified silicone oil, epoxy-modified silicone oil, ester-modified silicone oil, amine-modified silicone oil, and alcohol-modified silicone oil.
These are generally viscous liquids obtained by reacting a compound to be modified with polysiloxane.
[0017]
If necessary, conventionally known UV absorbers, antioxidants, pigments, dyes, and the like may be added to the PVB.
[0018]
The thermoplastic resin sheet of the present invention is formed of a laminated sheet of surface layer / inner layer / surface layer. The layer (A) composed of the PVB and the plasticizer is used for at least one of the surface layers, and the layer (B) composed of the PVB and the plasticizer is used for the inner layer. The layer (A) and the layer (B) are formed from the same components, but have different storage elastic moduli (G ′). That is, the storage elastic modulus (G ′) of the layer (A) at 40 ° C. and 10 rad / sec is set to be larger than that of the layer (B).
By setting the storage elastic modulus (G ′) between the layer (A) and the layer (B) such that the layer (A)> the layer (B), the thermoplastic resin sheet can be laminated glass. It is possible to improve the penetration resistance without lowering the physical properties such as transparency, weather resistance, alignment workability, and optical distortion when used as an intermediate film for use.
[0019]
In the laminated sheet, as means for setting the storage elastic modulus (G ') of the layer (A) to be larger than that of the layer (B), the polarity of PVB constituting the layer (B) is reduced so that the affinity with the plasticizer is reduced. Is higher than the layer (A), and the plasticizer contained in the layer (A) is transferred to the layer (B) to reduce the plasticizer content of the layer (A).
The polarity of PVB can be adjusted, for example, by the degree of saponification of PVA, which is a raw material of PVB, and the amount of unreacted residual hydroxyl groups when butyralized.
[0020]
The laminated sheet constituting the thermoplastic resin sheet is not particularly limited, but is preferably a three-layer laminated sheet of (1) layer (A) / layer (B) / layer (A), and (2) layer (A) / Layer (B) / layer (A) / layer (B) / layer (A).
In the case of a laminated sheet having three or more layers, the laminated structure may be asymmetric if at least one of the surface layers is the layer (A).
[0021]
The reason why the three-layer laminated sheet of the above-mentioned layer (A) / layer (B) / layer (A) is preferable is, in addition to the relative relationship between the dynamic viscoelasticity of the layer (A) and the layer (B), the obtained intermediate sheet. In the method of processing a film, good workability is obtained as in the case of a normal PVB-based interlayer.
[0022]
When the thermoplastic resin sheet of the present invention is used as an interlayer film for laminated glass, the thickness is preferably 0.3 to 1.6 mm.
The thicker the film, the better the penetration resistance is. However, considering the minimum penetration resistance required as a laminated glass, the above range is preferable.
[0023]
The layer (A) may be a single layer or a plurality of layers. If the thickness is small, the penetration resistance may be significantly reduced.
Further, the thickness of the layer (A) is preferably 10% or more of the total thickness of the intermediate film, because the penetration resistance improves as the thickness of the layer (A) increases.
[0024]
The method for producing the thermoplastic resin sheet of the present invention includes, for example, a method of separately forming the sheets constituting the layer (A) and the layer (B); a multilayer molding of the layer (A) and the layer (B). Conventionally known various methods such as a method of integrally molding using a machine are employed. Further, in the method of laminating a thermoplastic resin sheet intermediate film at the time of producing a laminated glass, the workability is reduced by laminating a plurality of laminated glass, and the optical distortion caused by poor smoothness of the interface between the interlayer films. Therefore, there is a problem that an image viewed through a laminated glass is distorted, and the like, and therefore, a method of integrally forming using a multilayer forming machine is preferable.
[0025]
In order to manufacture a laminated body (for example, laminated glass) using the thermoplastic resin sheet intermediate film, a method used for manufacturing a normal laminated glass is employed. For example, an intermediate film is formed by a glass plate from both sides. And a method of manufacturing a laminated glass by hot-pressing.
[0026]
(Action)
The thermoplastic resin sheet of the present invention is composed of a laminated sheet having a layer (A) composed of PVB and a plasticizer on any one of the surface layers and an inner layer composed of a layer (B) composed of PVB and a plasticizer. By setting the storage elastic modulus (G ′) of the layer (A) at 40 ° C. and 10 rad / sec larger than that of the layer (B), the penetration resistance can be improved. By being integrally molded using a molding machine, when used as an interlayer film for laminated glass, the laminated glass can be seen through due to optical distortion caused by deterioration in laminating workability and poor smoothness of the interface between interlayer films. Problems such as distorted images can be improved.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, examples of the present invention will be described.
(Example 1)
30 parts by weight of triethylene glycol-di-2-ethylhexanoate (3GO) was mixed with 100 parts by weight of PVB (average degree of polymerization 1700, degree of butyralization 65 mol%, residual acetyl group 1 mol%), and A resin for (A) was prepared.
Separately, 38 parts by weight of triethylene glycol-di-2-ethylhexanoate (3GO) are mixed with 100 parts by weight of PVB (average degree of polymerization 1700, degree of butyralization 68 mol%, residual acetyl group 1 mol%). Thus, a resin for the layer (B) was prepared. The resin for the layer (A) and the resin for the layer (B) are supplied to a multilayer molding machine to be integrally molded, and have a thickness of 0.75 mm including three layers (A) / layer (B) / layer (A). Was obtained. The thickness of each layer was 0.25 mm.
[0028]
Next, using a pair of embossing rolls, a large number of embosses made of fine mountain-shaped irregularities were applied to the layers (A) on both surfaces of the laminated sheet to produce an intermediate film having embossed patterns formed on both surfaces. The obtained intermediate film was allowed to stand for 2 hours in an atmosphere at a temperature of 20 to 25 ° C. and a relative humidity of 25 to 30% to control the humidity. The storage elastic moduli (G ') of the layer (A) and layer (B) single-layer films at 40 ° C. and 10 rad / sec were measured and are shown in Table 1.
[0029]
Furthermore, after the laminated glass structure (laminate) in which the embossed intermediate film is sandwiched between two transparent glass plates is placed in a rubber bag, the pressure in the rubber bag is degassed to 11.3 kPa, The temperature was raised to 80 ° C. in the degassed state, and kept at this temperature for 30 minutes. Next, it was placed in an autoclave and subjected to thermocompression bonding at a pressure of 1200 kPa and a temperature of 135 ° C. to obtain a transparent laminated glass.
Similarly, a total of 10 pieces of transparent laminated glass were prepared, left in an oven set at a predetermined temperature for 4 hours, and then evaluated for penetration resistance in accordance with JIS R3212. It was shown to. In addition, as the penetration resistance, a height at which the iron ball did not penetrate 50% was accepted and the height was indicated.
[0030]
The storage modulus (G ') was measured by the following method.
A circular sample having a diameter of 2.5 mm was prepared, and a measurement temperature of 40 ° C., a heating rate of 5 ° C./min, and a measurement frequency were measured using a solid viscoelasticity measuring device (“RMS-800” manufactured by Rheometrics Scientific). A sinusoidal strain of 10 rad / sec was applied in the shear direction with a strain amount of 0.1% and measured.
[0031]
(Example 2, Comparative Examples 1 to 3)
After forming the layer (A) and the layer (B) having the compositions shown in Table 1, a laminated glass was produced in the same manner as in Example 1. The storage elastic modulus (G ′) of the monolayer film of the layer (B) was measured in the same manner as in Example 1, and the results are shown in Table 1.
Further, the obtained laminated glass was evaluated for penetration resistance by the same method as in Example 1, and the results are shown in Table 1. In addition, the comparative example 1 used the single layer film of the layer (A).
[0032]
[Table 1]

[0033]
The laminated glasses of Examples 1 and 2 have better penetration resistance than Comparative Examples 1 to 3. Comparative Example 1 is a single-layer film, and Comparative Example 2 is a uniform layer in an autoclave because the surface layer and the inner layer have the same G ′ (similar to Comparative Example 1).
In Comparative Example 3, although G ′ of the surface layer> G ′ of the inner layer, since the resin structure is the same, a uniform layer “simply having a small number of plasticizer parts” is obtained in an autoclave.
[0034]
【The invention's effect】
Since the thermoplastic resin sheet of the present invention has the above-described configuration, it can be suitably used as an interlayer film for laminated glass, and the basic performance and transparency required for laminated glass such as transparency, weather resistance, and adhesiveness. The laminated glass obtained as a laminate exhibits excellent penetration resistance not only at room temperature but also at a high temperature, and has low optical distortion, as well as excellent workability of the laminated glass.

Claims (5)

A thermoplastic resin sheet comprising a laminated sheet in which a surface layer is laminated on both surfaces of an inner layer, wherein at least one surface layer is formed of a layer (A) composed of a polyvinyl butyral resin and a plasticizer, and the inner layer is composed of a polyvinyl butyral resin and The storage elastic modulus よ り (G ′) of the layer (A) formed from the layer (B) made of the agent and measured at 40 ° C. and 10 rad / sec is set to be larger than that of the layer (B). Characteristic thermoplastic resin sheet. 2. The heat according to claim 1, wherein the storage elastic modulus (G ′) of the layer (A) is set to be larger than that of the layer (B) by transferring the plasticizer from the layer (A) to the layer (B). Plastic resin sheet. 3. The thermoplastic resin sheet according to claim 1, wherein the polyvinyl butyral resin used for forming the layer (A) and the layer (B) has different polarities. A laminate comprising the thermoplastic resin sheets according to any one of claims 1 to 3 laminated. A laminated glass comprising the laminate according to claim 4.