JPH08267675A - Vinylidene fluoride resin composite film - Google Patents

Abstract

PURPOSE: To provide a vinylidene fluoride composite resin film with an excellent weatherability, anti-pollution and solvent resistance, besides, a good adhesiveness with a substrate. CONSTITUTION: The vinylidene fluoride resin composite film is constituted of an A layer consisting of a mixture of vinylidene fluoride or methacrylate resin, and a B layer consisting of a mixture of methacrylate or vinylidene fluoride resin. Also, the composite film includes a 2-30wt.% inorganic pigment and 0.1-15wt.% UV absorbing agent (The layers containing an inorganic pigment and UV absorbing agent are available either to be the same or not).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is excellent in weather resistance, stain resistance and solvent resistance, and has improved adhesion to plastics, rubbers and other substrates and prevents deterioration of the substrate due to transmission of light rays. And a vinylidene fluoride resin-based composite film. More specifically, the present invention relates to a vinylidene fluoride resin-based composite film composed of compositions having different mixing ratios containing vinylidene fluoride resin and methacrylate resin as main components.

[0002]

2. Description of the Related Art In recent years, polyvinyl chloride-based, polymethacrylate-based, and polyfluorine-based films have been used together with various paints as surface protection films for interior and exterior members. The applications of these protective films are not only for interiors such as wallpapers, elevators and vehicles, but also for roofing materials, wall materials, gutters, garage roofs, solariums, agricultural materials, signs, signs, labels, window glasses, etc. It is wide-ranging, taking advantage of its excellent weather resistance.

By the way, the protective films based on the above-mentioned three kinds of materials are used for various purposes depending on their prices, characteristics, etc., but in terms of price, the former is cheaper, while on the other hand, in terms of characteristics. The latter has better weather resistance. In addition, the target substrates for laminating these protective films are polyvinyl chloride, polycarbonate, polymethyl methacrylate, acrylonitrile-butadiene-
In addition to plastic base materials such as styrene copolymer and FRP,
EPDM, CSM and other rubber substrates, aluminum foil,
In addition to metal such as steel plate, it is widely used such as plywood and glass.

[0004]

However, among these three types of material films, the polyfluorine-based film has much better performance than the other two in terms of weather resistance, stain resistance, and strength. On the other hand, it has the disadvantage of poor adhesion to the substrate. Therefore, while polyvinyl chloride-based and polymethacrylate-based films use the heat-bonding method depending on the application, polyfluorine-based films all use an adhesive method, which is also expensive in terms of price. Therefore, the excellent weather resistance and stain resistance cannot be fully utilized, and there is a strong demand for the provision of this thermal adhesiveness.

The present invention is to improve the adhesiveness of a film made of vinylidene fluoride resin, and to combine a plurality of films having different mixing ratios of vinylidene fluoride resin and methacrylate resin. The present invention relates to a vinylidene fluoride resin-based composite film having excellent weather resistance, stain resistance, and solvent resistance, and excellent adhesion to a substrate to be bonded. The present invention also relates to a vinylidene fluoride resin-based composite film, which is provided with a photodeterioration-preventing effect by containing a pigment and an ultraviolet absorber in the film layer.

[0006]

Means for Solving the Problems That is, according to the present invention, an A layer made of vinylidene fluoride resin, 0 to 65 parts by weight of vinylidene fluoride resin and 100 parts of methacrylic acid ester resin are used.
To 35 parts by weight of the B layer as a component, a vinylidene fluoride resin-based composite film as a first invention, and 100 to 50 parts by weight of a vinylidene fluoride resin and a methacrylate ester-based resin. A vinylidene fluoride resin-based composite film comprising a layer A composed of 0 to 50 parts by weight and a layer B composed of a methacrylic acid ester resin as a second invention, and a first or second invention. In the invention, a vinylidene fluoride resin-based composite film, characterized in that at least one layer of layers A and B contains an ultraviolet absorber in an amount of 0.1 to 15% by weight.
In the first or second invention, at least one of the layers A and B contains 2 to 30% by weight of an inorganic pigment and 0.1 to 15% by weight of an ultraviolet absorber. The layer containing the ultraviolet absorber may be the same or different) and a vinylidene fluoride resin-based composite film is a fourth invention.

The vinylidene fluoride resin used in the present invention refers to a homopolymer of vinylidene fluoride or a copolymer of vinylidene fluoride and a monomer copolymerizable therewith. Examples of the copolymerizable monomer include vinyl fluoride, tetrafluoroethylene, and trifluorochloroethylene.

Next, the methacrylic acid ester resin means a homopolymer of methyl methacrylate as well as a copolymer of a monomer copolymerizable with methyl methacrylate. Examples of copolymerizable monomers include butyl methacrylate, ethyl methacrylate, and acrylic esters.

When a vinylidene fluoride resin is used for the composite film A layer (hereinafter referred to as A layer), the mixing ratio of the vinylidene fluoride resin and the methacrylic ester resin used for the composite film B layer (hereinafter referred to as B layer) is 0-65 parts by weight /
The amount is 100 to 35 parts by weight, because when the vinylidene fluoride resin exceeds 65 parts by weight, the excellent adhesiveness of the methacrylic acid ester resin is excluded.

On the other hand, composite film B layer (hereinafter referred to as B layer)
When a methacrylic acid ester-based resin is used, the mixing ratio of the vinylidene fluoride resin and the methacrylic acid ester-based resin used in the layer A is preferably 95 to 60 parts by weight / 5 to 40.
This is because the vinylidene fluoride resin cannot exhibit its excellent weather resistance, stain resistance and solvent resistance unless 50% by weight or more of vinylidene fluoride resin is present.

The film thicknesses of the layer A, the layer B and the entire layer are not particularly limited. However, when used as a protective film, the layer A has a thickness of 3 to 100 μm, the layer B has a thickness of 5 to 200 μm, and the layer has a thickness of 10 to 10 μm. About 300 μm is preferable. However, for applications that require solvent resistance, this is not the
It can be used with a thickness of

On the other hand, when it is used for the purpose of imparting a light-shielding property to at least one of the A layer and the B layer to improve the weather resistance of the substrate, the method of imparting the light-shielding property is as follows. Filler containing talc, calcium carbonate, carbon black, other blended inorganic pigments, red iron oxide,
This can be achieved by adding 2 to 30% by weight of a coloring agent. When the addition amount is less than 2% by weight, the light-shielding property becomes insufficient, and the adhesion between the composite film and the substrate to be bonded is deteriorated by the influence of light transmission, and the substrate itself may be deteriorated,
On the other hand, when the content exceeds 30% by weight, the light-shielding effect hardly changes, which causes difficulty in film formation due to poor dispersion of the inorganic pigment.

Further, as a method for further improving the weather resistance of the substrate in the state of the transparent film (particularly for the purpose of blocking ultraviolet rays), at least one of the A layer and the B layer is a benzotriazole type, benzophenone type, salicylic acid derivative. There is a method of adding 0.1 to 15% by weight of an ultraviolet absorber such as. If the addition amount is less than 0.1% by weight, the effect is small, and if it exceeds 15% by weight, the effect remains unchanged, which is economically disadvantageous. Further, as a method of improving the weather resistance of the base material, 2 to 30% by weight of an inorganic pigment and an ultraviolet absorber such as a benzotriazole-based, benzophenone-based, or salicylic acid derivative are used in at least one of the A layer and the B layer. 1 ~
There is a method of adding 15% by weight. 0.1% by weight of both added
If it is less than 15% by weight, the effect is small, and if it exceeds 15% by weight, the effect is not changed, which is economically disadvantageous.

Next, the manufacturing method will be described. The composite film according to the present invention comprises at least two layers, wherein at least one of the layers is melt-extruded and bonded together. In the melt extrusion molding, a twin screw extruder is used in addition to a general single screw extruder, and the following method is used as a method for integrally joining a plurality of layers. First, in a co-extrusion molding method using a T-die in which a plurality of extruders are used to bond resins in a molten state to form a multi-layer, a multi-manifold die is called, and a plurality of resin layers are brought into a sheet state and then contacted. There are a method of adhering and a method of calling a feed block die and spreading a plurality of resins into a sheet after adhering. A multilayer film can also be formed by a method using a round die, which is called an inflation molding method.

[0015] Next, called an extrusion lamination method, one of the layers to be integrally bonded is formed into a film in advance, and the other layer is extruded by heat or an adhesive (generally, an adhesive beforehand). Is applied). There is also a method in which both layers are formed into a film in advance and then integrated by using heat or an adhesive, but this is more disadvantageous than the previous method in terms of process and cost, and in the case of a thin film, adhesion is a technology. It's difficult to do.

The kneading of the resin with the inorganic pigment and the ultraviolet absorber may be carried out by a method of melting and kneading the resin and the pigment using an extruder or the like. For example, when an FCM type kneader from Kobe Steel is used, the dispersion is very good, and a raw material for a light-shielding layer having an excellent surface condition can be provided.

[0017]

EXAMPLES Hereinafter, a vinylidene fluoride resin is abbreviated as PVDF and a methyl methacrylate resin is abbreviated as PMMA. Vinylidene fluoride resin was manufactured by Penwort Co., Ltd., trade name Kaina-740 (hereinafter abbreviated as K-740), while methacrylic acid ester resin was manufactured by Mitsubishi Rayon Co., Ltd., trade name Acrypet MD (PMMA and MD). (Hereinafter abbreviated) and Hipet HBE (trade name of methyl methacrylate resin containing an acrylic rubber) manufactured by the company. The mixture of K-740 and MD or HBE was blended at a fixed ratio, melted and re-pelletized by a 30 mmφ different direction rotating twin screw extruder before use.

Example 1 K-740 was used as a raw material for layer A, while K-740 was used as a raw material for layer B.
PVDF / PMMA obtained from -740 and MD = 50/5
Using 0 products, two-layer coextrusion molding was performed using two 40 mmφ extruders and a multi-manifold die having a width of 300 mm and a slit of 0.5 mm. The cooling roll closest to the die of the take-off device was water-cooled. As shown in Table 1, the results of measuring the properties of the obtained composite film are as follows: A layer 15 μ, B layer 3
5μ, a total thickness of 50μ, excellent in stain resistance, weather resistance, and also excellent in thermal adhesion.

Example 2 PVDF / PMMA = 3 obtained from K-740 as the raw material for the A layer, and K-740 and MD similarly as the raw material for the B layer.
0/70 products, 40mmφ extruder, 65m each
m extruder and feedblock die, 450 mm width,
A two-layer film was coextruded using a T-die with a slit of 0.3 mm. At this time as well, the take-up roll near the T-die was water-cooled. The obtained two-layer film had a thickness of 5 μm for the A layer, 20 μm for the B layer and 25 μm in total. Each characteristic is shown in Table 1.

Example 3 PVDF / PMMA obtained from K-740 and MD = 60 /
A 40 μ film preformed by the T-die method from 40 products is used as the A layer, while MD is B
Extrusion lamination was performed using a 40 mmφ extruder and a T-die having a width of 330 mm and a slit of 0.5 mm for the layer. Table 1 shows the properties of the obtained two-layer film.

Example 4 PVDF / PMMA obtained from K-740 and MD = 80 /
20 parts by weight of 20 parts by weight of rutile-type titanium oxide were melt-kneaded into pellets using an FCM type kneader manufactured by Kobe Steel Ltd. The raw material was used for layer A, while 100 parts by weight of MD was used as an ultraviolet absorber as an ultraviolet absorber. 3 parts by weight of hydroxy-4-n-octoxybenzophenone were added, and 40
Film forming was performed using two mmφ extruders and a spiral type two-layer inflation die (die diameter 100 mmφ). Table 1 shows the properties of the obtained two-layer film.

Comparative Example 1 PVDF / PMMA obtained from K-740 and MD = 80 /
Twenty monolayer films were obtained by inflation molding.
The film having a thickness of 50 μm had good stain resistance and weather resistance, but did not provide satisfactory results in terms of thermal adhesion. The characteristics are shown in Table 2.

Comparative Example 2 PVDF / PMMA obtained from K-740 and MD = 30 /
70 monolayer films were obtained by T-die molding. The properties of the obtained film were as shown in Table 2.

Comparative Example 3 The characteristics of a commercially available methacrylate resin film having a thickness of 30 μm were measured, and the results are shown in Table 2.

Comparative Example 4 Table 2 shows the results of measuring the characteristics of a commercially available fluorine-containing film having a thickness of 25 μm.

[0026]

[Table 1]

[0027]

[Table 2]

The characteristics of Tables 1 and 2 were measured as follows. (1) Film thickness: Measured using a Peacock thickness gauge with a scale of 1/1000 mm. A and B of the two layers
The layer thickness was calculated from the extrusion rate of each extruder. (2) Tensile strength: conforming to JIS K-6732 Tensile speed 100 mm / min, MD is parallel to the extruder, TD is perpendicular to the extruder. (3) Light transmittance: in accordance with JIS-K-6714 (4) Weather resistance (A) Weather resistance acceleration test JIS A-141
5 (b) Yellowness measurement JIS K-7103 Yellowing index = Yellowness after exposure / Initial yellowness

(5) Stain resistance (A layer side) 1. Test method (1) Mark about 1 cm ^{2 on} each film with magic. (2) Dry and rub 30 times with gauze. (3) Remaining ink Evaluate with the naked eye 2. Evaluation criteria 1: Completely fall 2: Fall, but rubbing remains thin 3: 〃 残 る Dark: 4: Some fall, but some parts remain (parts that fall are also left) 5: (6) Solvent resistance (immersed only in layer A) (1) Test method: Evaluated visually after immersion in each solvent for 2 days at room temperature. (2) Evaluation criteria ：: no change △ to △: slight film shrinkage ：: film shrinkage 〜 to ×: film shrinkage / swelling x: film dissolution (7) Thermal adhesion (B layer side) Test method Base material: Soft PVC sheet for tablecloth 200μ Adhesive roll and conditions: mirror surface / silicone rubber 100φ ×
350 ml speed 1 m / min 2. Evaluation method A 25 mm wide laminated sheet was peeled 180 ° at a speed of 20 mm / min, and the strength was measured.

[0030]

The vinylidene fluoride resin-based composite film comprising the vinylidene fluoride resin and the methacrylic acid ester-based resin of the present invention has high strength / elongation and excellent long-term weather resistance of the vinylidene fluoride resin. Not only does it have excellent properties, but it also has excellent stain resistance and solvent resistance that can be easily removed even if water-based or oil-based inks or dust adhere. Moreover, since methacrylic acid ester-based resin is mixed and rich in adhesiveness, it can be used for wallpaper, interior of elevators and vehicles,
It can be applied to roofing materials, wall materials, rain gutters and the like.

Claims (4)

[Claims] An A layer comprising a vinylidene fluoride resin,
1. A vinylidene fluoride resin-based composite film comprising a B layer containing 0 to 65 parts by weight of vinylidene fluoride resin and 100 to 35 parts by weight of methacrylic acid ester resin. 2. An A layer composed of 100 to 50 parts by weight of vinylidene fluoride resin and 0 to 50 parts by weight of a methacrylic acid ester resin, and a B layer composed of a methacrylic acid ester resin. Vinylidene fluoride resin-based composite film. 3. The A layer and B according to claim 1 or 2.
0.1% by weight of UV absorber in at least one of the layers
To 15% by weight of the vinylidene fluoride resin-based composite film. 4. The inorganic pigment according to claim 1 or 2, wherein at least one of the layers A and B contains an inorganic pigment in an amount of 2 to 30% by weight and an ultraviolet absorber in an amount of 0.1 to 15% by weight. The vinylidene fluoride resin-based composite film, wherein the layers containing the absorbent may be the same or different.