JP2006213885A - Vinylidene fluoride-based resin film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film excellent in stain resistance, weather resistance, chemical resistance, etc., which are characteristics of fluorine-based resins and further having excellent antimicrobial performance which conventional fluorine-based films had not and a laminate to which the film is attached. <P>SOLUTION: The vinylidene fluoride-based resin film has a surface layer containing 100 pts.mass mixture of a vinylidene fluoride-based resin with a methacrylate-based resin and composed of 100-60 pts.mass vinylidene fluoride-based resin and 0-40 pts.mass methacrylate-based resin and 0.1-5 pts.mass silver-based inorganic antimicrobial agent. The laminate is obtained by attaching the film. The silver-based inorganic antimicrobial agent has, preferably, ≥2 μm average particle diameter and ≥1 wt.% silver content. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is excellent in stain resistance, antibacterial properties, chemical resistance, weather resistance and secondary processability, and is used for plastic plates used for interior and exterior members of buildings, displays, etc., particularly kitchens, bathrooms, toilets, The present invention relates to a vinylidene fluoride resin film suitably used as a surface protective material for various base materials requiring sanitary properties such as sanitary-related members, wall materials in hospitals, food factories, precision instrument factories, and the like, and a laminate thereof.

  Conventionally, plastic plates and plastic base materials used for interior and exterior parts of buildings, and other various base materials, such as vinyl chloride, acrylic, and fluorine films, for the purpose of improving durability and decoration. As a surface protective film, it is widely used as a surface material. In particular, as a surface material that is strongly required in weather resistance, contamination resistance, chemical resistance, etc., a fluororesin film is proposed in, for example, Patent Document 1 and Patent Document 2 for the purpose of improving adhesion to a substrate. It is widely used.

  However, the use of these surface protective films has been diversified more and more, and has antibacterial performance from the demand for hygiene as a response to SARS, avian influenza, O-157, etc., which have become social issues in recent years, In addition, surface materials having excellent weather resistance and contamination resistance are required.

  As a technique for enhancing the antibacterial performance, a method of coating an antibacterial agent on various substrates is used. More specifically, a method of applying a coating agent containing an antibacterial agent to the surface of the fluorinated film can be considered, but although there is a merit of imparting antibacterial performance, the surface is covered with a resin serving as a binder, and the fluorinated film Surface characteristics such as excellent weather resistance and stain resistance, which are characteristic of the film, are impaired.

There is also a technique for applying a weather-resistant coating. For example, as proposed in Patent Document 3, a method of forming a fluorine-based weather-resistant coating film on a resin surface is widely used. Although a method of adding an antibacterial agent to this coating film is conceivable, the coating method requires large-scale equipment represented by a dry laminator, making it difficult to handle small lots, and lowering productivity and increasing costs. It leads to. In addition, it is usually necessary to use a large amount of volatile organic compounds (VOC) such as ketones, vinyls, acrylics, and cell solves, and the effect of these discharges on the work environment and the surrounding environment is very large.
Japanese Patent Laid-Open No. 54-110271 JP-A-1-262133 JP 7-238264 A

  The present invention is a film having excellent weather resistance, stain resistance, chemical resistance, etc., which are characteristics of a fluorine-based resin, and excellent antibacterial performance, and a kitchen in which the film is laminated as a surface protective material, It is an object to provide sanitary-related members such as bathrooms and toilets, and wall materials for hospitals, food factories, precision instrument factories, and the like.

As a result of intensive studies to solve these problems, the present inventors have found that the problem can be achieved by a resin laminate obtained by adding a specific antibacterial agent to a surface layer mainly composed of vinylidene fluoride. The headline has led to the present invention.
That is, the present invention is based on 100 parts by mass of a mixture of vinylidene fluoride resin and methacrylate ester resin whose surface layer is composed of 100 to 60 parts by mass of vinylidene fluoride resin and 0 to 40 parts by mass of methacrylate ester resin. A vinylidene fluoride resin film containing 0.1 to 5 parts by mass of a silver-based inorganic antibacterial agent. Furthermore, the present invention relates to 100 parts by mass of a mixture of the above surface layer, vinylidene fluoride resin and methacrylic ester resin consisting of 40 to 0 parts by mass of vinylidene fluoride resin and 60 to 100 parts by mass of methacrylate ester resin. On the other hand, it is also a vinylidene fluoride-based resin film comprising at least two layers having a back layer containing 0.1 to 15 parts by mass of an ultraviolet absorber. Furthermore, the silver-based inorganic antibacterial agent used in the present invention preferably has an average particle diameter of 2 μm or more and a silver content of 1% by mass or more.
On the other hand, the film of the present invention can be used as the surface of the back layer printed. Moreover, this invention includes the manufacturing method of the vinylidene fluoride resin film which formed the surface layer and back surface layer of these films by the extrusion method, and also the laminated body which laminated | stacked these films on the base material.

  According to the present invention, the fluororesin has excellent weather resistance, chemical resistance, stain resistance, mechanical properties, secondary processability, etc., and has excellent antibacterial properties that have not been obtained with a fluororesin laminate so far. A film and its laminated body can be obtained. As a result, it can be used as a surface protection material such as an interior / exterior member of a building in a field that makes use of features having both antibacterial properties and weather resistance.

The present invention will be described in detail below.
The vinylidene fluoride resin used in the present invention refers to a homopolymer of vinylidene fluoride or a copolymer of monomers copolymerizable with vinylidene fluoride. Examples of the copolymer include a vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene copolymer and a vinylidene fluoride-hexafluoropropylene copolymer.

  The methacrylic ester resin used for blending with the vinylidene fluoride resin in the present invention refers to a homopolymer of methyl methacrylate or a copolymer with a monomer copolymerizable with methyl methacrylate. Examples of the copolymerizable monomer include acrylates having 2 to 4 carbon atoms such as methacrylic acid esters having 2 to 4 carbon atoms, methyl acrylate and butyl acrylate, styrene, α-methylstyrene, acrylonitrile, Examples include acrylic acid and other ethylenically unsaturated monomers. A copolymer of methyl methacrylate and an acrylate ester having 1 to 8 carbon atoms is preferable, and a methyl methacrylate copolymer having butyl acrylate or methyl acrylate as a comonomer is more preferable.

  The compounding ratio of the resin component of the film of the present invention is such that the resin composition when the film is a single layer is 100 to 60 parts vinylidene fluoride resin and 0 to 40 parts methacrylic ester resin, preferably fluorinated It is 95 to 60 parts of vinylidene resin, 5 to 40 parts of methacrylic ester resin, more preferably 90 to 65 parts of vinylidene fluoride and 10 to 35 parts of methacrylic ester resin. When the vinylidene fluoride resin is less than 60 parts, the excellent weather resistance and surface properties of the vinylidene fluoride resin are hardly exhibited. Further, when the film has a two-layer structure of a front surface layer and a back surface layer, the resin composition of the front surface layer is 100 to 60 parts of vinylidene fluoride resin and 0 to 40 parts of methacrylic ester resin, preferably fluorinated. It is 95 to 60 parts of vinylidene resin, 5 to 40 parts of methacrylic ester resin, more preferably 90 to 65 parts of vinylidene fluoride and 10 to 35 parts of methacrylic ester resin. When the vinylidene fluoride resin is less than 60 parts as in the case of a single layer, the excellent weather resistance and surface properties of the vinylidene fluoride resin are hardly exhibited. In this case, even if the surface layer does not contain a methacrylic ester resin, the adhesiveness with the back surface layer can be obtained, but the above range is preferable in that stronger adhesiveness can be obtained.

  The back layer in the case of a two-layer structure is 40 to 0 parts of vinylidene fluoride resin and 60 to 100 parts of methacrylic ester resin, and preferably contains 40 to 10 parts of vinylidene fluoride resin and butyl acrylate. 60 to 90 parts of methacrylic ester resin, more preferably 40 to 20 parts of vinylidene fluoride resin and 60 to 80 parts of methacrylic ester resin containing butyl acrylate and the like. If the amount of the methacrylic ester resin is less than 60 parts, sufficient adhesion may not be obtained when this film is laminated with various substrates. By using a resin containing butyl acrylate or the like as the methacrylic ester resin in the above range, durability when the laminate of the present invention is obtained is further improved. Moreover, even if it does not contain a vinylidene fluoride resin, adhesiveness with the surface layer can be obtained, but stronger adhesiveness can be obtained within the above preferred range.

  The film of the present invention may have a multilayer structure of three or more layers in which an intermediate layer is provided between the front surface layer and the back surface layer. In this case, the resin composition of the intermediate layer is preferably such that the ratio between the vinylidene fluoride resin and the methacrylic ester resin is between the front surface layer and the back surface layer in terms of interlayer adhesion.

  The silver-based inorganic antibacterial agent used in the present invention is one in which silver ions are supported on an inorganic compound, and the supported inorganic compound is a silicate-based zeolite, silica gel, silica-alumina, magnesium metasilicate aluminate, Examples of the glass include phosphate-based zirconium phosphate, calcium phosphate, and titanium oxide. In particular, a silver-based inorganic antibacterial agent supported on zeolite, glass, and phosphoric acid composite oxide is preferably used. As these silver-based inorganic antibacterial agents, those currently on the market can be used.

  Further, the silver content in the antibacterial agent and the particle size of the antibacterial agent greatly affect the expression of the antibacterial performance. The silver content is preferably 1% by weight or more, more preferably 1.5% by weight or more. The average particle diameter is preferably 2 μm or more, more preferably 2.5 μm or more and 10 μm or less. If it is 2 μm or less, the probability of protrusion to the film surface is lowered and there is a possibility that sufficient antibacterial performance may not be obtained. If it is 10 μm or more, uniform dispersion in the film may be difficult.

  In the surface layer of the film of the present invention, 0.1 to 5 parts by mass of the silver-based inorganic antibacterial agent is preferably added to the total 100 parts by mass of the resin components (in the film in the case of a single layer), preferably 0. .2-3 parts by mass, more preferably 0.3-2 parts by mass. When the silver antibacterial agent is less than 0.1 parts by mass, it is difficult to develop antibacterial properties. In the case of 5 parts by mass or more, it is difficult to uniformly disperse the silver antibacterial agent, resulting in poor appearance and transparency and an increase in cost.

  The film of the present invention includes various kinds of pigments, ultraviolet absorbers, stabilizers, dispersants, antioxidants, matting agents, fillers, processing aids, and the like as necessary in addition to the silver-based inorganic antibacterial agents. Additives can be added.

  The pigment to be used is not particularly limited, and inorganic pigments, organic pigments, pearl pigments, and the like can be used. In particular, inorganic pigments and complex oxide inorganic pigments are preferably used from the viewpoint of weather resistance. The addition amount of the pigment is 1 to 50 parts, preferably 5 to 30 parts with respect to 100 parts of the resin. When the content is less than 1 part, it cannot be uniformly dispersed in the film and partial color unevenness may occur. If added in excess of 50 parts, the dispersibility in the fluorine-based resin is remarkably lowered to cause a poor appearance, which is not preferable.

  Next, the ultraviolet absorber may be any one that is compatible with vinylidene fluoride resin and methacrylic ester resin. Examples of UV absorbers that can be used include benzotriazoles, oxalic acids, benzophenones, hindered amines, and many other types. Preferably, a high molecular weight type ultraviolet absorber having a molecular weight of 300 or more is suitably used in order to minimize volatilization when used as a manufacturing process or film.

  The addition amount of the ultraviolet absorber is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the resin. If it is less than 0.1 part, the ability to absorb ultraviolet rays is poor, and the suppression of deterioration due to ultraviolet rays may not be sufficient. Even if added in excess of 15 parts, the effect will not change, and it may cause poor dispersion. Costs also increase. When no pigment is added, it is desirable to add an ultraviolet absorber. Although the film itself has good weather resistance, when it is used without the addition of pigments, various bases can be used even if the ultraviolet rays reach various base materials and the surface vinylidene fluoride resin film does not deteriorate. This is because the material and the back surface printed layer are deteriorated first, which may cause a problem of peeling from the vinylidene fluoride resin film. Moreover, when using a ultraviolet absorber, it is desirable to provide the back surface layer which has a methacrylic ester resin as a main component in the surface layer containing a silver type inorganic antibacterial agent, and to add to the back surface layer side. This is because the surface layer can suppress bleeding out of the UV absorber on the back layer side.

  As a method of mixing various additives such as an ultraviolet absorber and a pigment into the film of the present invention, there is a method in which a resin and an additive are mixed in advance and melt kneaded using a commonly used single-screw extruder. Can be adopted. Also, as a method suitably used for improving dispersibility, a method using a high-kneading type twin screw extruder or a high-speed rotary mixer is used for premixing at a high temperature and then melt-kneading with a single screw extruder. By adopting the method, a film having an excellent surface state can be obtained.

  The film of the present invention is a multilayer film having at least a two-layer structure having a single layer and a back layer, and is obtained by manufacturing by a melt coextrusion molding method. In the case of a multi-layer film, a co-extrusion method using a T-die using a plurality of extruders to bring a resin into close contact in a molten state is referred to as a multi-manifold die. There are a method of bringing them into contact with each other and bringing them into contact with each other, and a method of spreading a plurality of resins in a sheet form after joining and adhering using a joining device called a feed block. Also, a method of using a round die, called an inflation molding method, can form a multilayer film by using a feed block.

  The film thickness of the film of the present invention is preferably 20 μm or more, more preferably 30 to 100 μm. When the thickness is less than 20 μm, the handling property is remarkably lowered, and sufficient weather resistance may not be obtained. If it exceeds 100 μm, it may be disadvantageous in terms of cost such as an increase in raw material costs, and secondary workability in thermoforming may be reduced.

  By performing decorative printing on the back surface of the film of the present invention and using various base materials, a heat laminating method, an adhesive, and a pressure-sensitive adhesive, it is possible to form a laminate having a design property. As a method for decorative printing, for example, gravure printing, screen printing, offset printing, etc. can be used using ink having affinity with the film, such as acrylic ink and fluorine-based ink. This printing is preferably performed on the back side of the film from the viewpoint that the printed surface can be protected, and from the viewpoint of weather resistance and antibacterial properties. As an apparatus used in the heat laminating method, a heat laminating machine having a heating type such as an external heating type, a hot air type, an infrared heating type, a high frequency internal heating type or the like can be used, and a hot press machine can be used. Adhesives that are widely used can be used, and acrylic adhesives and pressure-sensitive adhesives, epoxy adhesives, and urethane adhesives are preferably used. Needless to say, when the film of the present invention has a two-layer structure, the back layer side is mainly composed of a methacrylic ester resin, and lamination with various equipment using a thermal laminating method or an adhesive becomes easier.

  In order to obtain a laminate sheet or laminate which is a laminate of the film of the present invention and various substrates, in addition to using a heat laminating method or an adhesive, it can also be produced by a melt coextrusion molding method. That is, a single layer or two layers of the film of the present invention and various substrate layers are joined and adhered in a molten state by the above-described multi-manifold die or feed block to obtain a laminate. The advantage of this production method is that the balance between shrinkage and residual stress generated when the melt-adhered resin is cooled and solidified is relatively good, and the so-called curling phenomenon can be reduced. Furthermore, it is also possible to obtain the resin laminate of the present invention by melting one of the present film and various substrate layers and performing so-called extrusion lamination.

  Moreover, after obtaining the film of this invention, the method of laminating | stacking with the film and sheet | seat used as various base materials by thermoforming, such as press molding, vacuum forming, and pressure forming, is also possible. In-mold molding is also possible in which various base resin is melted and press-fitted into a mold into which the film of the present invention is inserted.

In addition, after obtaining the film of the present invention, after applying the adhesive on the back side and laminating the release paper and release film, it is pasted on the surface of various substrates in the factory, indoors or outdoors actually used It is also possible to attach to various substrate surfaces and impart weather resistance, stain resistance, and antibacterial properties.

Hereinafter, the present invention will be described in detail by way of examples.
(Examples 1-3)
Vinylidene fluoride resin, methacrylic acid ester resin, additives such as antibacterial agents and ultraviolet absorbers were blended using a tumbler at the blending ratio shown in Table 1 and kneaded by a 45 mmφ twin screw extruder. This resin was supplied to a 40 mmφ single-screw extruder and melt-plasticized to obtain a vinylidene fluoride-based single layer film using a T-type die. The obtained vinylidene fluoride single layer film was laminated with a PVC sheet (thickness 0.5 mm) using a commercially available acrylic pressure-sensitive adhesive to obtain a vinylidene fluoride laminated PVC sheet.
(Examples 4 and 5)
The antibacterial agent was blended only in the surface layer, and the ultraviolet absorber was blended only in the back layer, the raw materials of the surface layer and the back layer in the blending ratio shown in Table 2 were blended, and kneaded by a 45 mmφ twin screw extruder. Then, the resin of each of the front surface layer and the back surface layer was supplied to an individual 40 mmφ single-screw extruder and melt-plasticized to obtain a vinylidene fluoride two-layer film using a multi-manifold die. The film thickness ratio at this time is shown in Table 1. The two-layer film was heat-laminated using a roll-type heat laminator at a set temperature of 180 ° C., and a vinylidene fluoride-based two-layer film laminated PVC sheet was obtained in the same manner as a single layer.

  The antibacterial agent used was antibacterial agent A: aluminosilicate (M2 / n · Na2O · Al2O3 · 2SiO2 · xH20 (M: Ag, Zn)) with an average particle size of 2.5μm and silver content of 2.5wt%. %, Antibacterial agent B: phosphoric acid complex oxide (1 / 5Ag2O ・ (P2O5 ・ ZnO) m ・ (2CaO ・ 3B2O) n (m = 10, n = 1.0 to 1.4)) average particle size 5.0 ～ 10.0, silver content 1.95 wt%, antibacterial agent C: aluminosilicate (M2 / n, Na2O, Al2O3, 2SiO2, xH20 (M: Ag, Zn)), average particle size 2.5μm, silver A content of 0.3 wt% was used. (Hereinafter and in the table, it is described as antibacterial agent A, antibacterial agent B, and antibacterial agent C)

(Comparative Example 1)
A monolayer film was obtained in the same manner as in Examples 1 to 3 except that the monolayer vinylidene fluoride resin film containing no antibacterial agent was used at the blending ratio shown in Table 3. Moreover, it laminated | stacked with the PVC sheet by the method similar to Examples 1-3, and the lamination sheet was created.

(Comparative Example 2)
A monolayer methacrylic ester film was obtained in the same manner as in Examples 1 to 3, except that the blending ratio shown in Table 3 was an acrylic resin film that did not use a polyvinylidene fluoride resin. Moreover, it laminated | stacked with the PVC sheet by the method similar to Examples 4-5, and created the lamination sheet.

(Comparative Example 3)
In the blending ratio shown in Table 3, except that the antibacterial agent (in the table and hereinafter referred to as antibacterial agent D) is a single-layer vinylidene fluoride resin film using a stock solution of a natural antibacterial grapefruit seed extract. A single layer film was obtained in the same manner as in Examples 1 to 3. Moreover, the PVC sheet and the lamination sheet were produced by the method similar to Examples 1-3.

In Tables 1 to 3, “E” represents an index in the antibacterial evaluation column.
(Example: 6.9E3 = 6.9 × 10 ³ )

(Evaluation methods)
[Antimicrobial evaluation]
In the laminates of Examples 1 to 5 and Comparative Examples 1 to 4, an antibacterial test was performed by a method based on JIS Z2801. Detailed test methods are shown in Table 4.

  About Example 1, 2, 4, 5 and the comparative example 2, neither S. aureus and colon_bacillus | E._coli were detected after 24 hours, and it confirmed that it had the outstanding antimicrobial performance. Moreover, the same favorable result was shown also after the hot water immersion process of 50 degreeC x 16 hours supposing the use in the water circumferences, such as a kitchen and a bathroom. For Example 3, S. aureus was not detected. For E. coli, the number of bacteria in the control group immediately after inoculation was 120,000, compared to 6900 after the test (in the table: 6.9E3), the sterilization rate ((number of control cells immediately after inoculation-number of bacteria after test) / The number of control cells × 100 (%)) was 94%, confirming the antibacterial effect. As described above, Comparative Examples 1 and 3 were hardly sterilized after 24 hours, and most of the bacteria increased in number, and antibacterial performance was not confirmed. (Comparative example 1: Staphylococcus aureus number of target cells immediately after inoculation 2.4E5 / 2.0E5 sterilization rate after test 17%, E. coli number of target cells 2.8E5 immediately after inoculation 1.1E7 sterilization rate 0% or less Number of target bacteria 2.4E5 immediately after vaccination: 1.1E6 sterilization rate after test 0% or less, number of target cells 2.8E5 immediately after E. coli vaccination: 1.7E7 sterilization rate 0% or less after test Inoculation if sterilization rate is 0% or less (Indicates that the number of bacteria increased immediately after)

[Accelerated weather resistance evaluation]
The samples of Examples 1 to 5 and Comparative Examples 1 to 3 were subjected to an accelerated weather resistance test using an accelerated weather resistance tester manufactured by Daipla Intes and Eye Super UV Tester W-1. The test conditions were a black panel temperature of 63 ° C. and an irradiation / condensation cycle of 6 hours / 2 hours. The initial surface gloss (60 ° gloss) and the surface gloss after 300 hours test were measured and expressed as a ratio. The gloss retention ratios calculated were compared.

  In Examples 1 to 5 and Comparative Examples 1 and 3, the gloss retention was 80% or more, and it was confirmed that surface deterioration was suppressed. However, in Comparative Example 2, the gloss retention was It was small and it was confirmed that the surface deterioration was progressing.

[Chemical resistance evaluation]
Acetone was dropped on the sample surfaces of Examples 1 to 5 and Comparative Examples 1 to 3, the surface state was observed visually, and the evaluation results evaluated according to the following criteria are shown in Tables 1 to 3.
Excellent: No change on the surface.
Good: Some traces of damage to the surface are seen.
Bad: The surface is affected. Or a crack occurs.

  Examples 1 to 5 and Comparative Examples 1 and 3 showed good chemical resistance. Comparative Example 2 was significantly inferior in chemical resistance.

Claims (6)

  Silver-based inorganic antibacterials for 100 parts by mass of a mixture of vinylidene fluoride resin and methacrylic acid ester resin, whose surface layer is composed of 100 to 60 parts by mass of vinylidene fluoride resin and 0 to 40 parts by mass of methacrylic acid ester resin Vinylidene fluoride resin film containing 0.1 to 5 parts by mass of the agent.   To 100 parts by mass of a mixture of the surface layer according to claim 1 and vinylidene fluoride resin and methacrylate ester resin comprising 40 to 0 parts by mass of vinylidene fluoride resin and 60 to 100 parts by mass of methacrylate ester resin On the other hand, a vinylidene fluoride resin film comprising at least two layers having a back layer containing 0.1 to 15 parts by mass of an ultraviolet absorber.   The vinylidene fluoride resin film according to claim 1 or 2, wherein the silver-based inorganic antibacterial agent has an average particle size of 2 µm or more and a silver content of 1 mass% or more.   The vinylidene fluoride resin film according to any one of claims 1 to 3, wherein the surface of the back layer is printed.   The manufacturing method of the vinylidene fluoride resin film as described in any one of Claims 1-4 which formed the said surface layer and the back surface layer by the extrusion method.   The laminated body formed by laminating | stacking the vinylidene fluoride resin film as described in any one of Claims 1-5 on a base material.