JP2001130931A - Thermoplastic resin film and interlayer for laminated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject interlayer as a laminate composed of a functional film and a thermoplastic resin film excellent in handling operability when to be sandwiched by a pair of glass plates and in resistance to mutual blocking during their storage and in deaeration in preliminary pressure bonding process. SOLUTION: The subject thermoplastic resin film is such as to be laminated with a functional film; wherein the emboss roughness Rz on at least one side thereof, i.e., the surface to be in contact with the functional film, is <=20 μm and the embosses have marked line-like uneven shape. The other objective interlayer for laminated glass is obtained by laminating the above thermoplastic resin film with such a functional film as mentioned above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic resin film laminated with a functional film and an interlayer film for laminated glass.

[0002]

2. Description of the Related Art Conventionally, a laminated glass obtained by sandwiching an interlayer film for a laminated glass made of a thermoplastic resin film such as a plasticized polyvinyl butyral resin between at least a pair of glass plates and adhering and integrating the laminated films with each other has been used in automobiles. Widely used for window glasses of aircraft, buildings and the like.

[0003] In such an interlayer film for laminated glass, a functional film provided with a special function for the purpose of providing functions such as infrared reflection, ultraviolet absorption, decoration and the like in addition to safety is interposed. That has been done.

The above laminated glass is usually formed by sandwiching an interlayer film for laminated glass between at least a pair of glass plates and handling it by passing it through a gap between nip rolls, or by putting it in a rubber bag and sucking it under reduced pressure. The pre-press bonding is performed while degassing the air remaining between the glass plate and the interlayer film for laminated glass, and then the pre-press bonding is performed by heating and pressurizing in an autoclave, followed by integration.

The above-mentioned interlayer film for laminated glass has good basic properties required for laminated glass such as transparency, adhesion, weather resistance and penetration resistance, and also has an interlayer film for laminated glass during storage. It is required that they do not block each other, that they have good workability when sandwiching an interlayer film between glass plates, and that they have good degassing properties in the pre-compression bonding step in order to eliminate air entrapment. You.

[0006] In order to satisfy such demands, embosses having fine irregularities are usually formed on both surfaces of the interlayer film for laminated glass. As described above, when manufacturing a laminated glass using an interlayer film for laminated glass with a functional film such as infrared-reflective polyethylene terephthalate interposed, it is necessary not to generate wrinkles in the functional film layer, As the form of the fine unevenness, for example, Japanese Patent Application Laid-Open No. Sho 59-198148 discloses a method of using a smooth polyvinyl butyral sheet, and in the examples, a surface roughness of 3 μm.
No. 8 discloses a surface roughness Rz value of 12.7 μm in Examples.

However, in the above-mentioned conventional interlayer film for laminated glass, it is effective to prevent the generation of wrinkles in the functional film layer by limiting the emboss roughness of the surface. Reducing the emboss roughness of the interlayer film surface not only impairs the deaeration performance, which is the original role of the emboss, but also deteriorates the handling workability (such as sliding with glass) when handling the interlayer film for laminated glass. In addition, since the self-adhesiveness of the membrane itself is increased, blocking between the membranes is liable to occur, and it is necessary to take measures such as release paper rolls during storage.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems by improving the handling workability when sandwiching an interlayer film between glass plates and the blocking resistance between interlayer films for laminated glass during storage. An object of the present invention is to provide an interlayer film for laminated glass in which a functional film and a thermoplastic resin film are laminated while being excellent and having excellent degassing properties in a preliminary pressure bonding step.

[0009]

Means for Solving the Problems A thermoplastic resin film according to the invention of claim 1 (hereinafter referred to as invention 1) is a thermoplastic resin film laminated with a functional film, and At least one surface, which is in contact with the functional film, has an embossed roughness Rz of 20 μm or less, and the embossment has an indented uneven shape.

The thermoplastic resin film according to the invention of claim 2 (hereinafter referred to as invention 2) is characterized in that, in the thermoplastic resin film according to the above-described invention 1, the embossed irregularities are lattice-shaped.

In the thermoplastic resin film according to the third aspect of the present invention (hereinafter referred to as invention 3), the thermoplastic resin film according to the first or second aspect of the present invention has an embossed concavo-convex shape with a convex portion having an inverted V shape. It is characterized.

The interlayer film for laminated glass according to the invention described in claim 4 (hereinafter referred to as invention 4) comprises the above-mentioned functional film and the thermoplastic resin film according to any one of the above-mentioned inventions 1 to 3.

The functional film used in the invention 1 is not particularly limited, and includes, for example, a functional film such as polyethylene terephthalate (PET) provided with functions such as infrared reflectivity, ultraviolet absorbing property and decoration. .

Further, as the thermoplastic resin film used in the invention 1, a conventional interlayer film for a laminated glass (hereinafter, referred to as an interlayer film).
For example, a thermoplastic resin film used for an intermediate film is used. For example, a plasticized polyvinyl acetal resin film, a polyurethane resin film, an ethylene-vinyl acetate resin film, an ethylene-ethyl acrylate resin film, a plasticized A plasticized polyvinyl acetal resin film such as a plasticized polyvinyl butyral resin film is preferable. These thermoplastic resin films have excellent basic performance required for laminated glass, such as transparency, adhesion, weather resistance, and penetration resistance.

The thickness of the thermoplastic resin film is determined in consideration of penetration resistance and the like which are basically required as a laminated glass.
Preferably it is 0.2 to 2 mm.

Further, the thermoplastic resin film of the invention 1 is a thermoplastic resin film laminated with a functional film, wherein at least one surface of the thermoplastic resin film, which is in contact with the functional film, has an embossed surface. It is necessary that the thickness Rz is not more than 20 μm, and that the embossment has an indented uneven shape.

As a result, in the laminated glass obtained by using the intermediate film made of the thermoplastic resin film,
No wrinkles are generated in the functional film layer. Also,
By forming the concave / convex shape of the embossment into a ruled line, the concave / convex concave portion can form a continuous deaeration passage, and the deaeration becomes good.Moreover, since the concave / convex shape becomes regular, the concave / convex shape becomes regular. The contact area with the glass and the contact area between the interlayer films are reduced, so that the workability of handling the interlayer film is improved, and the self-adhesiveness can be reduced. The emboss roughness Rz is preferably 15 μm or less. Further, the embossed concavo-convex shape may be a lattice shape, and the embossed concavo-convex shape preferably has an inverted V-shape.

The method for forming the emboss on the thermoplastic resin film is not particularly limited, and includes, for example, an emboss roll method, a calender roll method, and a profile extrusion method. In order to obtain an emboss having irregularities, an emboss roll method is suitably used.

The embossed concavo-convex pattern is not particularly limited. In general, various fine concavo-convex patterns composed of a large number of convex portions and a large number of concave portions corresponding to these convex portions are formed. They may be distributed orderly and regularly, or they may be distributed randomly and irregularly. Further, the heights of the respective convex portions may be all the same, or may be different heights. Further, the depth of each concave portion with respect to each convex portion may be the same, or may be different.

The shapes of the convex portions and the concave portions are not particularly limited, and are generally truncated cones such as triangular pyramids, quadrangular pyramids, and cones, truncated triangular pyramids, truncated quadrangular pyramids, and truncated cones. Conical body, a convex and concave pattern composed of a number of convex portions such as a pseudo cone having a mountain-shaped or hemispherical head, and a number of concave portions corresponding to these convex portions, particularly, concave portions are continuous Is preferred.

Further, the size of the concave and convex portions of the emboss is not particularly limited, and the interval between the convex portions is generally 10 to 2000.
μm is preferred, and 50 to 1000 μm is more preferred.
Further, the height of the projection is preferably about 20 μm or less, more preferably 15 μm or less.

The method for producing a laminated glass using the interlayer film of the present invention is not particularly limited, and a production method in which pre-compression bonding and main compression bonding are performed as in ordinary laminated glass is employed.
For example, when using an intermediate film composed of a functional film such as an infrared reflective PET film and a thermoplastic resin film such as a plasticized polyvinyl butyral resin film, specifically, an intermediate film between two transparent inorganic glass plates is used. , The laminate is passed through a gap between nip rolls, and is preliminarily pressed while being deaerated while being treated at a pressure of about 0.2 to 1 MPa and a temperature of about 50 to 100 ° C. (handling deaeration method), or Put the laminate in a rubber bag, connect the rubber bag to the exhaust system, and
A method of pre-press bonding at about 60 to 100 ° C. (vacuum degassing method) or the like is employed as a pre-press bonding method while increasing the temperature while reducing the pressure by suction to -100 kPa vacuum (absolute pressure: 48 to 1 kPa). Next, the pre-pressed laminate is subjected to an autoclave or press in a usual manner using an autoclave or a press.
The laminated glass can be obtained by being completely press-bonded at a temperature of 150 ° C. and a pressure of about 0.2 to 1.5 MPa and integrated.

As the glass plate, not only a normal inorganic glass plate but also an organic glass plate such as a polycarbonate plate and a polymethyl methacrylate plate can be used.
The laminated structure of the laminated glass is not limited to a three-layer structure of a glass plate / interlayer / glass plate, but may be a multilayer structure such as a glass plate / interlayer / glass plate / interlayer / glass plate. Can be.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Example 1) (1) Production of laminated glass Plasticized polyvinyl resin having an embossed roughness Rz shown in Table 1, one surface of which is random, and the other surface has an embossed concavo-convex shape of a ruled line. An infrared reflecting functional layer was provided on the surface of the butyral resin film (0.76 mm thick) on the scribed side.
A PET film (XIR Construction, manufactured by Southwall) having a thickness of 0 μm is superimposed, sandwiched between transparent glass plates having a thickness of 2 mm from both sides, the obtained laminate is transferred into a rubber bag, and the rubber bag is connected to a suction decompression system. At the same time, heating is performed so that the temperature of the laminate (preliminary pressure bonding temperature) becomes a predetermined temperature, and at the same time, it is maintained at a reduced pressure of -80 kPa (absolute pressure 21 kPa) for 10 minutes,
The pressure was returned to the atmospheric pressure, and the pre-compression bonding was completed to obtain a laminated glass. The laminated glass thus pre-compressed is placed in an air-type autoclave at a temperature of 140 ° C. and a pressure of 1.3 M.
The main press was performed by hot pressing for 20 minutes under the condition of Pa to obtain a laminated glass.

(2) Evaluation The performance (surface roughness, handling workability, self-adhesive force and deaeration) of the intermediate film obtained in (1) was evaluated by the following methods. The results were as shown in Table 1.

1. Surface roughness The surface roughness Rz of the emboss of the intermediate film was measured using a surface roughness meter (trade name, SE-2000) manufactured by Kosaka Laboratory.

2. Handling workability Under an atmosphere of 25 ° C. and 25% RH, 10 cm
Place a × 10 cm glass for 30 seconds,
The maximum frictional resistance (g) when moving at a speed of 0 mm / min was measured to evaluate the workability of handling the interlayer film. The smaller the maximum frictional resistance, the better the handling workability (such as sliding with the glass) when the interlayer is sandwiched between the glass plates.

3. Self-adhesive force The intermediate film was cut into 15 cm × 15 cm, two of them were superimposed, and a 13 kg weight was placed thereon, allowed to stand at room temperature for 24 hours, and then 500 mm / min using a tensile tester.
A 180 ° peel test was performed at a speed of, the peel force (g) was measured, and the self-adhesive force of the intermediate film was evaluated (number of repetitions: 5). As the self-adhesive force is smaller, the interlayer films are less likely to adhere to each other,
Excellent blocking resistance during storage.

4. Degassing The pre-compression bonding temperature is 60 ° C, 80 ° C and 100 ° C,
A laminated glass was obtained by the method of (1). Baking test (12) of the laminated glass obtained at each pre-compression bonding temperature
(0 ° C. × 2 hours heating), the number of foams in 100 laminated glass samples was measured, and the degassing property of the interlayer film was evaluated. The smaller the number of foams, the better the degassing property of the interlayer in the pre-compression bonding step.

(Embodiment 2) Emboss roughness Rz shown in Table 1
An intermediate film and a laminated glass were obtained in the same manner as in Example 1 except that a plasticized polyvinyl butyral resin film having an embossed uneven shape was used.

(Comparative Example 1) Emboss roughness Rz shown in Table 1
An intermediate film and a laminated glass were obtained in the same manner as in Example 1 except that a plasticized polyvinyl butyral resin film having an embossed uneven shape was used.

The performance of the interlayer films obtained in Examples 2, 3 and Comparative Example 1 was evaluated in the same manner as in Example 1. The results were as shown in Table 1.

[0034]

[Table 1]

As is clear from Table 1, the intermediate film of the example according to the present invention has excellent workability in handling the film or blocking resistance during storage, and also has good degassing property in the intermediate film in the pre-compression bonding step. Are better.

On the other hand, at least one surface of the plasticized polyvinyl butyral resin film, the surface in contact with the above-mentioned functional film, and the intermediate film of Comparative Example 1 in which the embossed unevenness is not a scored line, the film handling workability Alternatively, the anti-blocking property during storage was inferior, and the degassing property of the interlayer in the pre-compression bonding step was also inferior.

[0037]

As described above, the interlayer film for laminated glass, in which the functional film and the thermoplastic resin film according to the present invention are laminated, can be handled easily when the interlayer film is sandwiched between the glass plates and the storage during storage. It has excellent blocking resistance between interlayer films, and also exhibits excellent performance in degassing of the interlayer film in the pre-compression bonding step. Therefore, it is suitably used for window glass of automobiles and the like.

Claims (4)

[Claims] 1. A thermoplastic resin film laminated with a functional film, wherein at least one surface of the thermoplastic resin film is
A thermoplastic resin film, wherein the surface in contact with the functional film has an emboss roughness Rz of 20 μm or less, and the emboss has an indented uneven shape. 2. The thermoplastic resin film according to claim 1, wherein the uneven shape of the emboss is a lattice. 3. The thermoplastic resin film according to claim 1, wherein the protrusions in the embossed concavo-convex shape have an inverted V-shape. 4. An interlayer film for laminated glass comprising the functional film and the thermoplastic resin film according to claim 1.