JPH0124064B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an exterior material, and more particularly to an exterior material provided with an elastic coating layer formed by applying and curing a specific fluorocarbon paint. Coatings for exterior materials require excellent durability, including weather resistance, abrasion resistance, and heat resistance.
Alkyd resin, phenolic resin, epoxy resin,
Although various paint resins such as acrylic resin and vinyl chloride resin have been developed, there are very few that satisfy all requirements. Fluororubber has excellent elasticity and wear resistance, and is an excellent coating material that satisfies the above characteristics. As a result of repeated research to develop an excellent fluorocarbon paint for exterior materials, the present inventors found that by adding a coupling agent to fluorocarbon rubber, it is possible to paint the exterior without impairing the above-mentioned properties of fluorocarbon rubber. The present invention was completed based on the discovery that the adhesion to the base material could be improved. That is, the gist of the present invention relates to an exterior material characterized in that an elastic coating layer is provided on the surface by applying and curing a fluorocarbon paint containing fluorocarbon rubber, a coupling agent, and a liquid carrier. The exterior materials of the present invention include a wide range of structures that are normally used outdoors, such as wall materials, panels, and other exterior materials for houses, gates, soundproof walls, road signs, and the like. The fluororubber contained in the fluororubber paint used in the present invention is a highly fluorinated elastic copolymer, and a particularly preferred fluororubber is usually 40 to 85 mol% of vinylidene fluoride. Examples include elastomeric copolymers of Ride and at least one other fluorine-containing ethylenically unsaturated monomer that can be copolymerized therewith. Further, as the fluororubber, fluororubber containing iodine in the polymer chain can also be preferably used. This iodine-containing fluororubber has, for example, 0.001 to 10% by weight, preferably 0.01 to 5% by weight of iodine bonded to the end of the polymer chain, and is copolymerized with the same 40 to 85 mol% of vinylidene fluoraloid as described above. This is a fluororubber whose main composition is an elastic copolymer comprising at least one other fluorine-containing ethylenically unsaturated monomer (see JP-A-52-40543).
Other fluorine-containing ethylenically unsaturated monomers that can be copolymerized with vinylidene fluoride to give an elastic copolymer include hexafluoropropylene,
Typical examples include pentafluoropropylene, trifluoroethylene, trifluorochloroethylene, tetrafluoroethylene, vinyl fluoride, perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether), perfluoro(propyl vinyl ether), etc. Ru. Particularly desirable fluororubbers are vinylidene fluoride/hexafluoropropylene dielastic copolymers and vinylidene fluoride/tetrafluoroethylene/hexafluoropropylene terelastic copolymers. In the fluororubber paint used in the present invention, the coupling agent refers to a compound that acts on the interface between an organic material and an inorganic material and forms a strong bridge between the two materials through chemical or physical bonding. titanium, zirconium, hafnium,
It is a compound of thorium, tin, aluminum, or magnesium, and has a group capable of bonding an organic material and an inorganic material. Among these coupling agents, preferred are silane coupling agents and orthoacid esters of Group transition elements of the periodic table (such as titanium or zirconium) and derivatives thereof, with aminosilane compounds being most preferred. Examples of the silane coupling agent include the general formula: R ¹・Si ・R ² _3-a・R ³ a [wherein R ¹ is a chlorine atom, an amino group, an aminoalkyl group, a ureido group, a glycidoxy group, an epoxycyclohexyl group] , acryloyloxy group,
An alkyl group having 1 to 10 carbon atoms or a vinyl group having at least one functional atom or group selected from a methacryloyloxy group, a mercapto group, and a vinyl group, R ² and R ³ are each a chlorine atom, a hydroxyl group, and a carbon number 1-10 alkoxy group, carbon number 2-15
alkoxy-substituted alkoxy group, hydroxyalkyloxy group having 2 to 4 carbon atoms, and 2 to 15 carbon atoms
an atom or group selected from the acyloxy groups of a
represents 0, 1 or 2. ] Examples include silane compounds represented by the following. R ¹ is an alkyl group having a functional substituent, and preferable examples thereof include β-aminoethyl group, γ-aminopropyl group, N-(β-aminoethyl)-γ-aminopropyl group. , γ-ureidopropyl group, γ-glycidoxypropyl group, β-
(3,4-epoxycyclohexyl)ethyl group,
Examples include γ-acryloyloxypropyl group, γ-methacryloyloxypropyl group, γ-mercaptopropyl group, β-chloroethyl group, γ-chloropropyl group, and γ-vinylpropyl group.
Further, R ¹ may be a vinyl group. Specific examples of the above-mentioned silane compounds that are preferably used include γ-aminopropyltriethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, and γ-glycidoxypropyl. Trimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethylsilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, vinyltris(β-methoxyethoxy) Silane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltriacetoxysilane, N-(trimethoxysilylpropyl)ethylenediamine, N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane, β-aminoethyl-β-aminoethyl -γ
-aminopropyltrimethoxysilane and the like. Among these silane coupling agents, aminosilane compounds such as γ-aminopropyltriethoxysilane (hereinafter referred to as A-1100), N-β-aminoethyl-γ-aminopropyltrimethoxysilane, N-(trimethoxysilylpropyl) Ethylenediamine, N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane, γ-ureidopropyltriethoxysilane, β-aminoethyl-β-aminoethyl-γ-
Compounds such as aminopropyltrimethoxysilane not only function as vulcanizing agents for fluorocarbon rubber, but also greatly contribute to improving adhesion to substrates, and are also safe to use with liquid carriers, so they are especially useful. preferable. Examples of compounds of titanium, zirconium, hafnium and thorium include the general formula: T(OR) ₄ [wherein T represents titanium, zirconium, hafnium or thorium, and R represents an alkyl group, a cycloalkyl group or an aryl group. ] Examples include derivatives obtained by reacting an orthoacid ester represented by the following and one or more compounds having at least one functional group therewith. Examples of the above-mentioned compounds having at least one functional group include glycerin, ethylene glycol, 1,
3-butanediol, 2,3-butanediol,
Polyhydric alcohols such as hexylene glycol and octylene glycol, oxyaldehydes such as salicylaldehyde and glucose, oxyketones such as diacetone alcohol and fructose, glycolic acid, lactic acid, dioxymaleic acid,
Oxycarboxylic acids such as citric acid, diketones such as diacetylacetone, ketonic acids such as acetoacetic acid, esters of ketonic acids such as ethyl acetoacetate, oxyamines such as triethanolamine and diethanolamine, oxyphenols such as catechol and pyrogallol. Compounds etc. can be used. Examples of specific compounds when T is titanium include tetraalkyl titanate (e.g., tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate), tetraethylene glycol titanate, triethanolamine titanate, titanium acetylacetonate. , isopropyl trioctanoyl titanate, isopropyl trimethacryl titanate, isopropyl triacryl titanate, isopropyl tri(butyl, methyl pyrophosphate) titanate, tetraisopropyl di(dilauryl phosphite) titanate,
Examples include dimethacryloxyacetate titanate, diacryloxyacetate titanate, di(dioctyl phosphate) ethylene titanate, and the like. As the zirconium compound, a compound similar to the above titanium compound can be used. Specific examples include tetraalkyl zirconates such as tetraethyl zirconate and tetrabutyl zirconate, n-propyl zirconate, isopropyl zirconate, n-butyl zirconate, isobutyl zirconate, zirconium acetylacetonate, and the like. As the hafnium and thorium compounds, compounds similar to titanium and zirconium can be used. As the tin compound, an organic or inorganic compound such as SnCl ₄ can be used. Examples of aluminum compounds include aluminum isopropylate, monosec-butoxyaluminum diisopropylate, aluminum sec-butyrate, ethyl acetoacetate aluminum diisopropylate, and aluminum tris (ethylacetoacetate). Examples of the magnesium compound include magnesium alcoholates such as magnesium methylate and magnesium ethylate. The liquid carrier used in the fluororubber paint of the present invention is selected from organic solvents such as lower ketones, lower esters, and cyclic ethers, water, and mixtures of water and water-soluble organic liquids, and the water-soluble organic liquid is alcohol. can be exemplified. Among these liquid carriers,
Water is most preferred since it does not impair painting workability. By adding a fluororesin to the fluororubber coating used in the present invention, non-adhesion can be imparted to the surface of the fluororubber coating. In this case, the ratio of fluorocarbon rubber to fluorocarbon resin is preferably 95:5 to 35:65 by weight. If the ratio of fluorocarbon resin is less than the above lower limit, the desired non-adhesive and lubricious properties can be achieved. The improvement is not sufficient, and conversely, when the amount exceeds the above upper limit, a coating film of the desired thickness cannot be obtained, and cracks and pinholes are likely to occur in the coating film. In the present invention, the fluororubber coating film obtained by blending a specific amount of fluororesin can impart excellent non-adhesive properties to the surface without substantially impairing the adhesion to the substrate and mechanical properties. Because the fluororesin, which itself has non-adhesive properties, surprisingly gathers on the surface of the fluororubber coating, it does not adversely affect the adhesion to the substrate or the mechanical properties of the coating.
It is believed that the above-mentioned performance of the fluororesin is effectively exhibited on the surface of the fluororubber coating film. According to our research, when we measure the fluorine content on the surface of a 50μ thick coating film cured at 300℃ for 30 minutes and on the adhesive surface with the substrate using fluorescent X-ray analysis, we find that It has been confirmed that the former shows about 1.5 times the amount, and the higher the curing temperature, the more the ratio of the former to the latter tends to increase. The fluororesins used in the present invention include polytetrafluoroethylene, tetrafluoroethylene, and at least one other ethylenically unsaturated monomer copolymerizable with the same (e.g., olefins such as ethylene and propylene, hexafluoroethylene, Examples include copolymers with propylene, vinylidene fluoride, chlorotrifluoroethylene, halogenated olefins such as vinyl fluoride, perfluoroalkyl vinyl ethers, etc.), polychlorotrifluoroethylene, polyvinylidene fluoride, and the like. Among these, preferred fluororesin is at least one of polytetrafluoroethylene, tetrafluoroethylene and hexafluoropropylene, perfluoromethyl vinyl ether, perfluoroethyl vinyl ether, and perfluoropropyl vinyl ether (usually 40 mol% based on tetrafluoroethylene). (included below). Inorganic fibrous substances as other substances contained in the fluororubber paint used in the present invention are used to increase the compression complexity of the fluororubber paint, and typical examples include glass fiber, carbon fiber, Examples include asbestos fibers and potassium titanate fibers. This inorganic fibrous material has an average length of at least 1μ,
The thickness is preferably 1 to 100μ. The amine compound optionally added to the fluororubber paint used in the present invention primarily functions as a vulcanizing agent for the fluororubber, and together with the coupling agent, improves mechanical properties. Examples of compounds include ethylamine, propylamine, butylamine, benzylamine,
Monoamines such as allylamine, n-amylamine, ethanolamine, ethylenediamine, trimethylenediamine, tetramethylenediamine,
Diamines such as hexamethylene diamine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5,5]undecane (hereinafter referred to as V-11), diethylenetriamine,
Examples include polyamines such as triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine, among which amine compounds having two or more terminal amino groups are preferred. To prepare the fluororubber paint used in the present invention, pigments, acid acceptors, fillers, etc. are usually blended into a mixture of fluororubber, liquid carrier, and optionally added fluororesin (if necessary, A surfactant may be used), and a coupling agent and, if necessary, an amine compound are added to the resulting dispersion (additives such as the pigment, acid acceptor, filler, etc. may be added as necessary). ) A uniform fluororubber paint can be obtained by thoroughly mixing using a conventional method. The amount of coupling agent added is usually fluoro rubber.
1 to 50 parts by weight per 100 parts by weight, preferably 1 to 50 parts by weight
It is 20 parts by weight. When an amine compound is added as desired, it is blended so that the total sum of the coupling agent and the amine compound takes the above value. in this case,
The molar ratio of the coupling agent to the amine compound is selected from the range of 1:99 to 99:1. As the acid acceptor, those commonly used in the vulcanization of fluororubber can be similarly used, such as one or more divalent metal oxides or hydroxides. Specific examples include oxides or hydroxides of magnesium, calcium, zinc, lead, and the like. Further, as the filler, silica, clay, diatomaceous earth, talc, carbon, etc. are used. The fluororubber paint used in the present invention is applied or impregnated onto a base material by a conventional coating method, and is cured for an appropriate period of time at a temperature of room temperature to 400°C, preferably 100 to 400°C. The desired fluororubber coating can then be obtained. The film thickness of the fluoro rubber paint used in the present invention is 5μ
It is preferable that it is above. If the film thickness is less than 5 μm, there is a risk that unevenness will occur over the entire surface of the base material and that some areas will not be coated. The fluororubber coating film obtained in this way has the properties inherent to fluororubber, such as heat resistance, weather resistance, abrasion resistance, oil resistance, solvent resistance, and chemical resistance, as well as adhesion to the substrate. Fluororubber coatings containing fluororesin have non-adhesive and lubricious surfaces. The exterior material of the present invention has resistance to abrasion caused by salt damage and sand, and has excellent impact resistance due to its rubber elasticity. Exterior materials coated with fluorocarbon rubber coatings containing fluoroplastics also have excellent stain resistance. Furthermore, the fluororubber paint used in the present invention also has the advantage that it can be processed at relatively low temperatures as described above. Next, the present invention will be explained by showing Examples and Comparative Examples. Note that parts indicate parts by weight. Examples 1 to 2 (Example 1) A mixture of 100 parts of the following liquid A and 5 parts of liquid B was separately purified using a 200-mesh wire mesh to prepare a fluororubber paint. A Liquid fluororubber 1) Aqueous dispersion (fluororubber content 60% by weight, including Nonion HS-208) 166 parts fluororesin 2) Aqueous dispersion (fluororesin content 50% by weight, (Including Nonion HS-208) 150 parts Magnesium oxide 3 parts Medium thermal carbon 20 parts Nonion HS-210 2 parts Water 50 parts B Liquid A-1100 40 parts V-11 20 parts Water 40 parts Note 1 Vinylidene fluoride/tetra Fluoroethylene/hexafluoropropylene elastomeric copolymer. Note 2 Tetrafluoroethylene/hexafluoropropylene copolymer. On the other hand, an aluminum plate having a length of 100 mm, a width of 50 mm, and a thickness of 1 mm was degreased by washing with acetone. The above paint was spray-painted on the degreased aluminum plate surface, and then dried at 50 to 70°C for 10 minutes.
A coating film with a thickness of 30μ was formed, and the coating film was cured at 300°C for 10 minutes. The contact angle of the obtained coating film with water was measured by dropping one drop of pure water at 24° C. using a goniometer (manufactured by Elma Optical Co., Ltd.) and found it to be 110°. (Example 2) A fluororubber paint was prepared in the same manner as in Example 1 except that the fluororesin was not used, and it was applied onto an aluminum plate and cured to form a coating film, and the contact angle with water was measured. The contact angle was 80°. Example 3 The fluororubber paint prepared in Example 1 was applied to iron, aluminum, and ceramics in the same manner as in Example 1.
It hardens to form a coating film, and a knife is used to cut 1mm into this coating film.
I carved 100 corner squares. The cellophane adhesive tape peel test was repeated 5, 10 and 20 times. The remaining numbers are shown in Table 1.

[Table] Example 4 and Comparative Example 1 The fluororubber paint obtained in Example 1 was applied to an aluminum plate at a spray pressure of 2.0 kg/cm ² , and applied and cured in the same manner as in Example 1 to a thickness of approximately 28 μm. A coating film was formed. This coating film was sprayed from a distance of 15 cm using Tosa Emery #100 at an air pressure of 5 kg/cm ² , and the time for starting exposure of the base and the time for complete peeling of the coating film were measured. For comparison, a base material of galvanized steel plate with a chemical conversion film formed on its surface was coated with primer and then vinylidene fluoride resin paint was applied.
A test piece was prepared by baking at 300°C for 1 minute. A wear resistance test was conducted on this test piece in the same manner as above. The results are shown in Table 2.

【table】

Claims (1)

[Scope of Claims] 1. An exterior material comprising an elastic coating layer formed by coating and curing a fluororubber paint containing fluororubber, a coupling agent, and a liquid carrier on the surface. 2. The exterior material according to claim 1, wherein the fluororubber paint further contains a fluororesin. 3 The weight ratio of fluorocarbon rubber and fluorocarbon resin is 95:5 or more
35:65 of the exterior material according to claim 2. 4. The exterior material according to claim 1, wherein the coupling agent is blended in a ratio of 1 to 50 parts by weight based on 100 parts by weight of fluororubber. 5. The exterior material according to any one of claims 1 to 4, wherein the fluororubber paint further contains an amine compound. 6. The exterior material according to claim 5, wherein the amine compound has at least one terminal amino group directly connected to an aliphatic hydrocarbon group. 7. The packaging material according to claim 6, wherein the amine compound has at least two terminal amino groups. 8. The exterior material according to any one of claims 1 to 7, wherein the fluororubber paint further contains an inorganic fibrous substance.