JPH0550566A - Production of vinylidene fluoride resin type composite film - Google Patents

Abstract

PURPOSE:To obtain excellent weatherability, antifouling properties and solvent resistance and also hold the adhesiveness to a base material to be bonded using a composite film consisting of a vinylidene fluoride resin and a methacrylic ester resin. CONSTITUTION:A composite film is formed by extruding an A-layer composed of a component consisting of 100-50 pts.wt. of a vinylidene fluoride resin and 0-50 pts.wt. of a methacylic ester resin and a B-layer composed of a component consisting of 0-65 pts.wt. of a vinylidene fluoride resin and 100-35 pts.wt. of a methacrylic ester resin in a molten state to integrally bond both layers.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a vinylidene fluoride resin and a methacrylic acid ester-based resin having excellent weather resistance, stain resistance and solvent resistance, and improved adhesion to plastics, rubber and other substrates. The present invention relates to a method for producing a vinylidene fluoride resin-based composite film containing a resin as a main component.

[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 range of properties, making the most of its weather resistance. By the way, the above-mentioned protective films based on three types of materials are used for various purposes depending on their prices, characteristics, etc., but in terms of price, the former is cheaper, while the latter is weatherproof. It has excellent properties.

Substrates to which these protective films are attached are not only plastic substrates such as polyvinyl chloride, polycarbonate, polymethylmethacrylate, acrylonitrile-butadiene-styrene copolymer and FRP but also EPD.
In addition to M, CSM and other rubber substrates, metals such as aluminum foil and steel plates, it also has a wide range of plywood and glass.

[0004]

However, among these three kinds of material films, the polyfluorine-based film has much higher performance than the other two in terms of weather resistance, stain resistance and strength. On the other hand, it has the drawback of being poor in adhesiveness to the substrate.

Therefore, the polyvinyl chloride-based film and the polymethacrylic acid ester-based film adopt the heat-bonding method depending on the application, while the polyfluorine-based film uses the adhesive method in which the adhesive method is used. Also in terms of price, the price is high, and 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 form a composite film of vinylidene fluoride resin and methacrylic acid ester resin or two kinds of films having different mixing ratios. It is intended to provide a method for producing a vinylidene fluoride resin-based composite film which is excellent in weather resistance, stain resistance and solvent resistance by using, and also has good adhesiveness to a substrate to be adhered.

[0007]

Means for Solving the Problems That is, the present invention provides an A layer containing 100 to 50 parts by weight of a vinylidene fluoride resin and 0 to 50 parts by weight of a methacrylic acid ester resin, and a vinylidene fluoride resin of 0 to 65 parts by weight. A vinylidene fluoride resin-based composite film, characterized in that a composite film comprising a B layer containing 100 parts by weight of methacrylic acid ester resin and 100 to 35 parts by weight of a methacrylic acid ester resin is melt-extruded and integrally bonded. It is a manufacturing method.

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

The methacrylic acid ester-based resin is a copolymer of a homopolymer of methyl methacrylate and another 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. / 5 to 40 parts by weight, which is because the excellent weather resistance, stain resistance and solvent resistance cannot be exhibited unless the vinylidene fluoride resin is present in an amount of 50 parts by weight or more.

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

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 obtained by mixing a vinylidene fluoride resin and a methacrylic acid ester resin is interposed in the intermediate layer, the adhesiveness between the A layer and the B layer is increased. improves. Layer A,
The film thicknesses of the B layer and the entire layer are not particularly specified, but when used as a protective film, the A layer has a thickness of 3 to
100 μ, B layer is 5 to 200 μ, and the entire layer is 10 to 300 μ
A degree is preferable. However, it is not limited to this and can be used with a thickness of several mm in applications requiring solvent resistance.

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 base material, the method of imparting the light-shielding property is as follows. Fillers containing talc, calcium carbonate, carbon black, red iron oxide and other formulated inorganic pigments,
It can be achieved by kneading a colorant. Moreover, either one of the layers may have a two-layer structure, and the other layer may be laminated thereon to form a three-layer structure, and the layer corresponding to the intermediate layer of the two-layer structure may be used as the light-shielding layer.

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), benzotriazole type, benzophenone type, salicylic acid derivative in at least one of the A layer and the B layer is used. A method of kneading an ultraviolet absorber such as At this time, it is more effective to use a radical scavenger and an antioxidant together.

Next, the manufacturing method will be described. The composite film according to the present invention is characterized in that it is composed of two layers, A layer and B layer, and is melt-extruded and integrally bonded.

For the melt extrusion molding, a general single-screw extruder as well as a twin-screw extruder is used, and the following method is available as a method for integrally bonding a plurality of layers.

First, 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 multilayer structure is called a multi-manifold die, and a plurality of resin layers are formed into sheets. After that, there is a method of contact bonding and a method called a feed block die, and a method of spreading a plurality of resins into a sheet after bonding. A multilayer film can also be formed by a method called an inflation molding method, which uses a round die.

Next, in order to impart a light-shielding property to at least one of the A layer and the B layer, it is necessary to add a pigment in an amount of about 2 to 30% by weight. Although the method of melt kneading may be used, in general, the pigment is not sufficiently dispersed, and when a high-speed rotation and high-shear kneading machine such as FCM type kneading machine of Kobe Steel is used, the dispersion of the pigment becomes very good and the surface condition It is possible to provide excellent raw materials for the light shielding layer.

[0019]

[Example] In addition, vinylidene fluoride resin was changed to PVDF,
The methyl methacrylate resin will be abbreviated as PMMA. Vinylidene fluoride resin is a product of Pen Walt, trade name Kainer 740 (hereinafter abbreviated as K-740), and methacrylate ester resin is a product of Mitsubishi Rayon Co., Ltd., trade name Acrypet MD (hereinafter referred to as PMMA MD Abbreviated) and the company's trade name HiPET HBE (methyl methacrylate resin containing acrylic rubber, abbreviated as HBE below). K-740 and MD
Or, for HBE mixture, blend these in a fixed ratio,
The product was melted and re-pelletized with a 30 mmφ counter-rotating twin-screw extruder in advance.

Example 1 PVDF / PMMA = 80/20 obtained from K-740 and MD as raw materials for layer A
On the other hand, PVDF / P obtained from K-740 and MD as raw material for layer B
Using MMA = 50/50, 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-up device was water-cooled. The results of measuring the respective properties of the obtained composite film are as shown in Table 1, A layer 15μ, B layer 35μ,
With a total thickness of 50μ, it was excellent in stain resistance, weather resistance, and thermal adhesion.

Example 2 PVDF / PMMA = 70/30 obtained from K-740 and MD as a raw material for layer A
Was obtained from K-740 and MD as raw material for layer B
PVDF / PMMA = 30/70, 40mmφ extruder, 65
A two-layer film was coextruded using a mmφ extruder and a feed block die, a T-die having a width of 450 mm and a slit of 0.3 mm. Also at this time, the take-up roll near the T-die was water-cooled. The obtained two-layer film is A layer 5
μ, B layer 20 μ, total thickness 25 μ. Each property shows the results as shown in Table 1.

Example 3 PVDF / PMMA = 60/40 obtained from K-740 and MD as a raw material for layer A
Was obtained from K-740 and MD as raw material for layer B
PVDF / PMMA = 20/80 product, 40mmφ extruder, 65
A two-layer film was coextruded using a mmφ extruder and a feed block die, a T-die having a width of 450 mm and a slit of 0.3 mm. Also at this time, the take-up roll near the T-die was water-cooled. The obtained two-layer film is A layer 10
μ, B layer 30 μ, total thickness 40 μ. Each property shows the results as shown in Table 1.

Example 4 100 parts by weight of PVDF / PMMA = 80/20 obtained from K-740 and MD and 20 parts by weight of rutile type titanium oxide were melt-kneaded into pellets using an FCM type kneader manufactured by Kobe Steel. Made raw material for A layer,
On the other hand, PVDF / PMMA = 40/60 obtained from K-740 and MD was used as a layer B for film formation using two 40 mmφ extruders and a spiral type two-layer inflation die (die diameter 100 mmφ). .. The characteristics of the obtained two-layer film showed the results shown in Table 1.

Example 5 PVDF / PMMA = 80/20 obtained from K-740 and MD as raw materials for layer A
On the other hand, as a raw material for layer B, K-740 PVDF / rubber PM
MA (HBE) = 40/60 product, 40mmφ extruder, 65mm
A two-layer film was coextruded using a φ 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, 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 A PVDF / PMMA = 80/20 monolayer film obtained from K-740 and MD was subjected to inflation molding. The 50 μm-thick film had good stain resistance and weather resistance, but did not give satisfactory results with respect to thermal adhesion. The characteristics are shown in Table 2.

Comparative Example 2 A single layer film of PVDF / PMMA = 30/70 obtained from K-740 and MD was used.
Obtained by T-die molding. The characteristics of the obtained film were as shown in Table 2.

Comparative Example 3 As a result of measuring the characteristics of a commercially available methacrylic acid ester resin film having a thickness of 30 μ, the values shown in Table 2 were obtained.

Comparative Example 4 As a result of measuring the characteristics of a commercially available fluorine film having a thickness of 25 μ, the values shown in Table 2 were obtained.

[0029]

[Table 1]

[0030]

[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. The thicknesses of the A and B layers of the two layers were calculated from the extrusion rate ratio of each extruder.

(2) Tensile strength: tensile speed according to JIS K-6732
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 accelerated test JIS A-1415 (b) Yellowness measurement JIS K-7103 Yellowing index = yellow after exposure Degree / 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 with gauze 30 times. 3 Visually evaluate the remaining ink. 2. Evaluation criteria 1: Completely falls. 2: Drops but remains thin after rubbing. 3: It drops, but remains thick after rubbing. 4: A part falls, but there is a place (the place where it falls still remains). 5: Almost does not fall.

(5) Solvent resistance (only the 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 ○: Slight film shrinkage △: Film shrinkage △ to ×: Film shrinkage / swelling ×: Film dissolution

(7) Thermal Adhesiveness (B Layer Side) 1. Test Method Base Material: Soft PVC Sheet for Tablecloth 2
00μ Bonding roll and conditions: mirror surface / silicone rubber 100φ × 350
mm liter speed 1 m / min 2. Evaluation method 180 mm of 25 mm width laminated sheet at 20 mm / min
° Peel and measure strength.

[0037]

The vinylidene fluoride resin-based composite film obtained by the production method of the present invention has high strength and elongation, and not only has excellent long-term weather resistance of the vinylidene fluoride resin, It has excellent stain resistance and solvent resistance that can be easily removed even if water-based or oil-based inks and dust adhere. Moreover, since it is mixed with a methacrylic acid ester-based resin and has excellent adhesiveness, it can be applied to applications such as wallpaper, interiors of elevators and vehicles, roofing materials, wall materials, rain gutters, and the like.

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Claims (1)

[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. ~ 35 parts by weight of B
A method for producing a vinylidene fluoride resin-based composite film, which comprises melt-extruding a composite film composed of a layer and bonding them together.