JPH07195633A - Vinylidene fluoride resin type composite film - Google Patents

Abstract

PURPOSE:To provide a film excellent in weatherability, antistaining properties and solvent resistance and also excellent in the adhesiveness with a base material to be subjected to bonding. CONSTITUTION:A vinylidene chloride resin type composite film is constituted of an A-layer consisting of 100-50 pts.wt. of a vinylidene fluoride resin and 0-50 pts.wt. of a methacrylic ester resin and a B-layer consisting of 10-65 pts.wt. of a vinylidene fluoride resin and 100-35 pts.wt. of a methacrylic ester resin. When the A-layer is composed of a vinylidene fluoride resin alone and the B-layer is composed of a methacrylic ester resin alone, a film composed of a mixture of a vinylidene fluoride resin and a methacrylic ester resin is interposed as an intermediate layer. The respective layers of this film have mutually different compsns. Further, the vinylidene chloride resin type composite film contains 2-30wt.% of inorg. pigment and 0.1-15wt.% of an ultraviolet absorber (the inorg. pigment and the ultraviolet absorber may be added to the same layer or different layers).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is excellent in weather resistance, stain resistance and solvent resistance, has improved adhesiveness with plastics, rubber 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, it relates to a vinylidene fluoride resin-based composite film composed of a composition containing a vinylidene fluoride resin and a methacrylic acid ester resin as main components and having different mixing ratios.

[0002]

2. Description of the Related Art In recent years, polyvinyl chloride-based films, polymethacrylic acid ester-based films, polyfluorine-based films and the like have been used as a surface protective film for interior and exterior members together with various coating materials. These protective films are used for wallpaper, elevators, interiors such as vehicles, roof materials, wall materials, rain gutters, garage roofs, solariums, agricultural materials, signs, signs, labels, window glass, etc. It has a wide variety of properties, making the most of its 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 substrates such as styrene copolymer and FRP,
EPDM, CSM and other rubber substrates, aluminum foil,
A wide range of metals such as steel plates, plywood, glass, etc.

[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 improves the adhesiveness of a film made of vinylidene fluoride resin, and is a combination of a plurality of films having different mixing ratios of vinylidene fluoride resin and methacrylic ester resin. The present invention relates to a vinylidene fluoride resin-based composite film which is excellent in weather resistance, stain resistance and solvent resistance and also has good adhesiveness to a substrate to be adhered. 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 containing 100 to 50 parts by weight of vinylidene fluoride resin and 0 to 50 parts by weight of methacrylic acid ester resin, and vinylidene fluoride resins 0 to 65 are used. A composite film comprising a B layer containing 100 parts by weight and 100 to 35 parts by weight of a methacrylic acid ester resin as a component, wherein the A layer is a vinylidene fluoride resin alone or the B layer is a methacrylic acid ester resin alone. In the case, it is a composite film having a film in which a vinylidene fluoride resin and a methacrylic acid ester resin are mixed as an intermediate layer, and each layer has a different composition from each other. In the first invention, in the first invention, A layer, B
The inorganic pigment in at least one of the layers and the intermediate layer
A vinylidene fluoride resin-based composite film comprising 30% by weight and 0.1 to 15% by weight of an ultraviolet absorber (the layers containing the inorganic pigment and the ultraviolet absorber may be the same or different). This is a second invention.

The vinylidene fluoride resin used in the present invention refers to a vinylidene fluoride homopolymer or a copolymer of vinylidene fluoride and a copolymerizable monomer. 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 the copolymerizable monomer include butyl methacrylate, ethyl methacrylate, and acrylic acid esters.

The mixing ratio of the vinylidene fluoride resin and the methacrylic acid ester resin used for the composite film A layer (hereinafter referred to as A layer) is 100 to 50 parts by weight / 0 to 50 parts by weight, preferably 95 to 60 parts by weight. 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.

On the other hand, composite film B layer (hereinafter referred to as B layer)
The mixing ratio of the vinylidene fluoride resin and the methacrylic acid ester resin used for is 0 to 65 parts by weight / 100 to 35 parts by weight, preferably 20 to 50 parts by weight / 80 to 50 parts by weight. This is because when the vinylidene resin exceeds 65 parts by weight, the excellent adhesiveness of the methacrylic acid ester resin is excluded.

Further, the A layer is a vinylidene fluoride resin alone,
In the case where the B layer has a film structure composed of a methacrylic acid ester resin alone, when a film in which a vinylidene fluoride resin and a methacrylic acid ester resin are mixed is interposed in the intermediate layer, the adhesiveness between the A layer and the B layer is increased. Is improved. A
The film thicknesses of the layer, the B layer and the whole layer are not particularly specified, but when used as a protective film, the A layer is 3
˜100 μ, B layer is 5 to 200 μ, and the total layer is 10 μm.
It is preferably about 300 μm. However, it is not limited to this and can be used in a thickness of several mm for applications requiring solvent resistance.

On the other hand, when used for the purpose of imparting a light-shielding property to at least one of the layers A, B and the intermediate layer to improve the weather resistance of the substrate, the method of imparting the light-shielding property is as follows. It can be achieved by adding 2 to 30% by weight of a filler and a colorant containing other inorganic pigments such as titanium oxide, talc, calcium carbonate, carbon black and red iron oxide. If the addition amount is less than 2% by weight, the light-shielding property becomes insufficient and the adhesiveness between the composite film and the substrate to be adhered deteriorates due to the effect of light transmission, and further, the substrate itself may deteriorate. If the amount exceeds 30% by weight, the light-shielding effect is hardly changed, and it becomes difficult to form the film due to poor dispersion of the inorganic pigment.

As a method for further improving the weather resistance of the base material (particularly for the purpose of blocking ultraviolet rays), a benzotriazole-based material is used for at least one of the A layer, the B layer and the intermediate layer.
An ultraviolet absorber such as a benzophenone type or salicylic acid derivative is added in an amount of 0.1 to 15% by weight, preferably 0.5 to 6% by weight. If the addition amount is less than 0.1% by weight, the effect is small,
If it exceeds 15% by weight, the effect is almost unchanged,
It becomes economically disadvantageous.

Next, the manufacturing method will be described. The composite film according to the present invention comprises at least two layers, at least one of which is melt-extruded and integrally bonded. In addition to a general single-screw extruder, a twin-screw extruder is also used for melt extrusion molding, and the following method is available as a method for integrally bonding 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.

Next, referred to as an extrusion laminating method, one of the layers to be integrally bonded is previously formed into a film, and the other layer is extruded while heat or an adhesive (generally an adhesive is used in advance). Can also be used. 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 resin, the inorganic pigment and the ultraviolet absorber may be kneaded by a method of melt-kneading the resin and the pigment using an extruder or the like, but in general, the dispersion is not sufficient, and the kneader is a high speed rotation and high shear kneader. For example, when an FCM type kneader manufactured by Kobe Steel is used, dispersion becomes 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. The vinylidene fluoride resin is manufactured by Pen Walt Co., Ltd., trade name Kaina-740 (hereinafter abbreviated as K-740), while the methacrylic acid ester resin is manufactured by Mitsubishi Rayon Co., Ltd., trade name Acripet MD (hereinafter referred to as MD by PMMA). Abbreviated) and Hipet HBE (trade name, manufactured by the same company) (methyl methacrylate resin containing acrylic rubber, hereinafter abbreviated as HBE). The mixture of K-740 and MD or HBE was blended at a constant ratio, melted and re-pelletized in advance with a 30 mmφ counter-rotating twin-screw extruder before use.

Example 1 PVDF / obtained from MD and K-740 as raw materials for layer A
PMMA = 80/20 product is used as K-
740 and PVDF / PMMA obtained from MD = 50/50
2 multi-manifold dies with 40mmφ extruder and 300mm width and 0.5mm slit.
Layer coextrusion was performed. The cooling roll closest to the die of the take-up 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 35
The total thickness was 50 μm, and the total thickness was 50 μm, which was excellent in stain resistance, weather resistance, and thermal adhesion.

Example 2 PVDF / obtained from K-740 and MD as raw materials for layer A
PMMA = 70/30 was used as the raw material for layer B, and PVDF / PMMA = 30 obtained from K-740 and MD.
/ 70 products, 40 mmφ extruder, 65 mm
A two-layer film was coextruded using an extruder and a feed block die, a T-die having a width of 450 mm and 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 is
The thickness of the layer A was 5μ, the layer B was 20μ, and the total was 25μ. Each characteristic is shown in Table 1.

Example 3 PVDF / PMMA obtained from K-740 and MD = 60 /
A film of 40 μ, which was previously formed by the T-die method from 40 products as a raw material, was used for the A layer, while K-74
PVDF / PMMA = 20/80 obtained from MD and MD was subjected to extrusion lamination using a 40 mmφ extruder and a T-die having a width of 330 mm and a slit of 0.5 mm for the B layer. The characteristics of the obtained two-layer film are shown in Table 1.

Example 4 PVDF / PMMA obtained from K-740 and MD = 80 /
20 parts by weight of rutile type titanium oxide to 100 parts by weight of 20 products were melt-kneaded and pelletized using an FCM type kneader manufactured by Kobe Steel, Ltd. for the layer A, while PVDF / MD obtained from K-740 and MD was used. PMMA = 40/60 To 100 parts by weight of the product, 3 parts by weight of 2-hydroxy-4-n-octoxybenzophenone as an ultraviolet absorber was added, and 4 for the B layer.
Film formation was performed using two 0 mmφ extruders and a spiral type two-layer inflation die (die diameter 100 mmφ). The characteristics of the obtained two-layer film are shown in Table 1.

Example 5 PVDF / obtained from K-740 and MD as raw materials for layer A
PMMA = 80/20 product is used as K-
740 PVDF / rubber PMMA (HBE) = 40
/ 60 products, 40 mmφ extruder, 65 mm
φ extruder and feed block die, 450mm width,
A two-layer film was coextruded using a T-die with a slit of 0.3 mm. At this time, the take-up roll closest to the T-die was water-cooled. Table 1 shows the properties and thickness of the obtained two-layer film.

Comparative Example 1 PVDF / PMMA obtained from K-740 and MD = 80 /
20 monolayer films were obtained by inflation molding.
The 50 μm-thick film had good stain resistance and weather resistance, but thermal adhesiveness did not give satisfactory results. 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 characteristics of the obtained film were as shown in Table 2.

Comparative Example 3 Table 2 shows the results of measuring the properties of a commercially available methacrylic acid ester resin film having a thickness of 30 μm.

Comparative Example 4 The results of measuring the characteristics of a commercially available fluorine-based film having a thickness of 25 μm are shown in Table 2.

[0027]

[Table 1]

[0028]

[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 acceleration test JIS A-141
5 (b) Yellowness measurement JIS K-7103 Yellowness index = yellowness after exposure / initial yellowness

(5) Contamination resistance (A layer side) 1. Test method (1) Mark each film with a marker of about 1 cm ² (2) After drying, scrape off with gauze 30 times (3) Residual ink Evaluate with the naked eye 2. Evaluation criteria 1: Complete drop 2: Drops but remains thin after rubbing 3: 〃 〃 remains dark 4: Partially drops, but some remains (parts that fall remain) 5: Almost no deterioration (6) Solvent resistance (only layer A side is immersed) (1) Test method: Immersed in each solvent for 2 days at room temperature and evaluated visually. (2) Evaluation criteria ○: No change ‖: Film shrinks slightly, Δ: Film shrinkage Δ to ×: Film shrinkage / swelling ×: Film dissolution (7) Thermal adhesiveness (layer B side) 1. Test method Base material: soft vinyl chloride sheet for table cloth 200μ Bonding 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.

[0031]

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, because it is mixed with methacrylic acid ester resin and has excellent adhesiveness, it can be used for interiors such as wallpaper, elevators and vehicles.
It can be applied to applications such as roofing materials, wall materials, and gutters.

Claims (2)

[Claims] 1. A layer comprising 100 to 50 parts by weight of vinylidene fluoride resin and 0 to 50 parts by weight of methacrylic ester resin, 0 to 65 parts by weight of vinylidene fluoride resin and 100 of methacrylic acid ester resin. Is a composite film composed of a layer B containing 35 to 35 parts by weight as a component,
When the A layer is a vinylidene fluoride resin alone or the B layer is a methacrylic acid ester resin alone, it is a composite film in which a film obtained by mixing a vinylidene fluoride resin and a methacrylic acid ester resin is interposed in the intermediate layer. A vinylidene fluoride resin-based composite film, wherein each layer has a different composition. 2. The inorganic pigment according to claim 1, wherein at least one of the A layer, the B layer and the intermediate layer 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. A layer containing an ultraviolet absorber may be the same or different). A vinylidene fluoride resin-based composite film.