JPH0737117B2 - Contamination resistant titanium material and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a titanium material having improved stain resistance by forming a fluorine-containing polymer film having excellent adhesion, processability, weather resistance and stain resistance. And a manufacturing method thereof.

[Conventional technology]

Conventionally, galvanized steel sheets, painted steel sheets and the like have been mainly used as metal building materials. However, these steel sheets are known to have insufficient corrosion resistance under severe corrosive environments such as coastal zones, industrial zones or subtropical zones.

Therefore, as a metal material to replace these steel plates,
Colored aluminum and colored stainless steel sheets have come to be used, but these materials also do not show sufficient corrosion resistance in the above-mentioned high corrosive environment, and depending on the degree of corrosive environment, white rust may occur in a few months to several years. And pitting corrosion are recognized.

Therefore, recently, titanium material, which is extremely excellent in corrosion resistance as a metal building material, has been attracting attention, but for titanium material, if stains such as fingerprints or oil adhere to it,
Contamination is very conspicuous as compared with other metal materials, and in order to improve such a problem, a method of applying a paint for preventing pollution is adopted.

[Problems to be solved by the invention]

However, when coating a titanium material with a stain prevention paint, the titanium material is a material that is extremely excellent in corrosion resistance and weather resistance,
The coating applied with this material is required to have high corrosion resistance and weather resistance, which are not inferior to those of titanium materials. In addition to this, adhesion and workability of the coating are also required. It could not be said to satisfy the above. That is, the acrylic, polyester, urethane, and silicon-based paints that are commonly used for surface protection of color iron plates and the like have insufficient weather resistance of the coating film, and when exposed to a highly corrosive environment for a long time, There is a problem that the coating film is yellowed and blisters are generated on the coating film to impair the aesthetics, and the coating film peels off, so that the effect of using the titanium material is not enjoyed.

On the other hand, the applicant of the present application has developed a stain resistant titanium material having improved stain resistance by forming a fluoropolymer film having excellent adhesion, weather resistance and stain resistance on the surface of the titanium material, I am applying. However, in this stain resistant titanium material, there is room for further improvement in the long-term adhesion of the coating film, for example, the long-term adhesion outdoors, that is, under ultraviolet irradiation.

In view of the above points, the present invention has a stain-resistant titanium material capable of significantly improving the adhesion of a coating film under ultraviolet irradiation when forming a fluorine-based polymer film on the surface of the titanium material, and a method for producing the same. Is intended to be provided.

[Means for solving problems]

In the atmosphere, the surface of titanium is covered with an oxide film, and in coated titanium, this oxide film (TiO ₂ ) is in contact with the coating film. It is generally known that titanium dioxide is slightly reduced by ultraviolet rays to generate atomic oxygen radicals (O.) as shown in the following formula (1).

Due to such a reaction, the following factors for lowering the adhesiveness are present at the interface between titanium and the coating film.

Decrease in Adhesion Due to Atomic Oxygen Radicals O · Oxygen radicals O · are very active and oxidize and destroy the vehicle in the coating film. Therefore, the vehicle has a low molecular weight, which reduces the interfacial strength and the adhesiveness. Examples of this molecular weight reduction reaction include the reaction shown in Formula (2).

Decrease in adhesion due to change of TiO ₂ to Ti ₂ O _{3 The} adhesion between the coating film and titanium is due to the bond between polar groups such as hydroxyl groups in the coating film and oxygen of TiO _{2 in} the oxide film. Therefore TiO ₂
Is changed to Ti ₂ O ₃ , the polarity of oxygen is weakened, and the adhesiveness is reduced, resulting in peeling. In order to avoid the above-mentioned deterioration in adhesion, it is necessary to prevent the reaction of the above formula (1). As a result of various studies, the present inventor has found that if ultraviolet rays do not reach the titanium interface by adding a substance that absorbs ultraviolet rays such as benzophenone and benzotriazole to the coating film, the adhesion of the coating film for a long period of time will be improved. It was found to be sustainable.

Therefore, the invention of the first item of the present application, on the surface of the titanium material,
Silane-based, aluminate-based, titanate-based,
Alternatively, the stain resistant titanium material is characterized in that a fluorine-based polymer film containing a coupling agent and an ultraviolet absorber made of a mixture thereof is formed.

Further, the invention of the second aspect is such that the ultraviolet absorber is added to the fluorine-based polymer.
A method for producing a stain resistant titanium material, characterized in that a coating material containing 0.1 to 30 wt% is applied to the surface of the titanium material.

The ultraviolet absorber referred to in the present invention absorbs ultraviolet rays,
Alternatively, it is an additive capable of preventing deterioration of the coating film by trapping oxygen radicals generated by irradiation of the coating film with ultraviolet rays. Examples thereof include aromatic ester derivatives, benzophenone derivatives, benzotriazole derivatives, triazine derivatives and substituted acrylonitrile derivatives. Particularly preferred are benzophenone derivatives such as 2,2'-dihydroxy-4-methoxybenzophenone, dibenzoylrosorcin, hydroxyphenylbenzotriazole and the like.

Further, the titanium material to which the present invention is applied may be any surface finish such as a pure finish, a pickling finish, etc., and a mirror finish, a heline finish, an emboss finish or a panel finish. Well, even anodization,
It may be a color titanium material that has been subjected to a coloring treatment such as atmospheric heating oxidation or chemical oxidation, or a film formed by PVD, CVD or the like. It should be noted that these can be used in any shape or size such as plate, rod, tubular, etc., but the most common one is to continuously perform secondary processing including painting, cutting, etc. It is a long coiled product that is convenient above.

Further, as the fluorine-based polymer, any polymer containing a considerable amount of fluorine in the molecule can be used. Considering comprehensively the adhesion to titanium material, weather resistance, and the original purpose of preventing pollution, for example, the reactivity of tetrafluoroethylene resin, trifluoroethylene chloride resin, vinylidene fluoride resin, hydroxyl group, etc. Examples thereof include fluoroolefin-based polymers having a group. Particularly, from the viewpoints of workability, solvent resistance of the coating film, strength, etc., a fluoroolefin polymer having a reactive group and soluble in a solvent is preferably adopted.

Examples of such fluoroolefin polymers include tetrafluoroethylene, chlorotrifluoroethylene, trifluoroethylene, vinylidene fluoride, monofluoroethylene, hexafluoropropylene or (per) fluoroalkyl trifluorovinyl ether [provided that (per) fluoroalkyl The number of carbon atoms in the group is 1 to 4], and fluoroalkyl vinyl ethers such as hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether or hydroxyhexyl vinyl ether are particularly preferable, and β-hydroxyethyl (meth ) Acrylates, (meth) acrylates such as β-hydroxypropyl (meth) acrylate, β-hydroxybutyl (meth) acrylate. Copolymer monomers and copolymerizable monomers having a reactive group, such as hydroxyalkyl esters of Le acid was copolymerized are preferable. Such monomers include ethyl vinyl ether, n-propyl vinyl ether, iso-propyl vinyl ether, n-butyl vinyl ether, iso-butyl vinyl ether, t-butyl vinyl ether, lauryl vinyl ether, octadecyl vinyl ether, 2-chloroethyl vinyl ether or cyclopentyl vinyl ether, Alkyl or cycloalkyl vinyl ethers such as cyclohexyl vinyl ether and methyl cyclohexyl vinyl ether;
2,2,3,3-tetrafluoropropyl vinyl ether, 2,2,
3,3,4,4,5,5-octafluoropentyl vinyl ether,
2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluorononyl vinyl ether, trifluoromethyl vinyl ether, pentafluoroethyl vinyl ether, heptafluoro (Per) fluoroalkyl vinyl ethers such as propyl vinyl ether, heptadecafluorooctyl vinyl ether, undecafluorocyclohexyl vinyl ether; vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl bivalate, vinyl cyclohexanecarboxylate, vinyl benzoate. , p−tert
-Butyl vinyl benzoate, vinyl ester of aliphatic monocarboxylic acid having a branched alkyl group of C _{2 to} C ₉ , vinyl caproate, vinyl caprate, vinyl caprylate,
Vinyl carboxylates such as vinyl laurate or vinyl stearate; Olefins or chloroolefins such as ethylene, propylene, vinyl chloride or vinylidene chloride; methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate Alternatively, there are (meth) acrylic acid esters such as cyclohexyl (meth) acrylate. Among them, it is preferable to use at least one selected from the group consisting of cycloalkyl vinyl ether, alkyl vinyl ether and carboxylic acid vinyl ester in combination. When a carboxylic acid vinyl ester is used in combination, a vinyl ester of an aliphatic monocarboxylic acid having a C _{4 to} C ₁₇ branched alkyl group and cyclohexanecarboxylic acid are used in terms of the balance of hardness and flexibility of the cured coating film. It is particularly preferable to use at least one selected from the group consisting of vinyl acid salt, vinyl benzoate, and pt-butyl vinyl benzoate.

In addition, it is preferable that the fluorine-containing polymer film is used in combination with a crosslinking agent in addition to the above-mentioned fluorine-containing polymer because the mechanical properties of the film are improved. As such a crosslinking agent, one that reacts with the reactive group of the fluoroolefin polymer is used. Typical examples include aminoplasts, polyisocyanate compounds, blocked polyisocyanate compounds, melamine compounds, polybasic acids and polybasic acid anhydrides.

Furthermore, it does not matter whether the fine particle pigment is added to the fluoropolymer.

Examples of the silane coupling agent include silane compounds represented by the general formula: R ¹ .Si.R ² _3-a ▼ R ³ _a .

In the formula, R ¹ is a chlorine atom, amino group, aminoalkyl group, ureido group, glycidoxy group, epoxycyclohexyl group, acryloyloxy group, methacryloyloxy group,
An alkyl group having 1 to 10 carbon atoms or a vinyl group having at least one kind of functional atom or group selected from a mercapto group and a vinyl group, R ² and R ³ are a chlorine atom, a hydroxyl group, and 1 to 10 carbon atoms, respectively. An atom or a group selected from an alkoxy group, an alkoxy-substituted alkoxy group having 2 to 15 carbon atoms, a hydroxyalkyloxy group having 2 to 4 carbon atoms and an acyloxy group having 2 to 15 carbon atoms, and a represents 0, 1 or 2. .

R ¹ is an alkyl group having a functional substituent, and preferred 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, γ-acryloyloxypropyl group, γ-methacryloyloxypropyl group, γ-mercaptopropyl group, β- Chloroethyl group, γ-chloropropyl group, γ-
A vinyl propyl group etc. can be illustrated. R ¹ may be a vinyl group.

Specific examples of the above-mentioned silanes that are preferably used include, for example, γ-aminopropyltriethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane and γ-glycidoxypropyltrisilane. Methoxysilane, 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 can be mentioned.

As a titanate-based coupling agent, a titanium compound will be described as a typical example, but not only titanium but also titanium
Includes zirconium, hafnium and thorium compounds in Group IVa.

Examples of the compound of titanium, zirconium, hafnium and thorium include, for example, 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. ] The ortho acid ester shown by these and this at least 1
There may be mentioned a derivative obtained by reacting one or more kinds of compounds having individual functional groups. Examples of the compound having at least one functional group include polyhydric alcohols such as glycerin, ethylene glycol, 1,3-butanediol, 2,3-butanediol, hexylene glycol, octylene glycol, salicylaldehyde and glucose. Such as oxyaldehydes, diacetone alcohol, oxyketones such as fructose, glycolic acid, lactic acid, dioxymaleic acid, oxycarboxylic acids such as citric acid, diketones such as diacetylacetone,
Ketone acids such as acetoacetic acid, ketone acid esters such as ethyl acetoacetate, oxyamines such as triethanolamine and diethanolamine, and oxyphenol compounds such as catechol and pyrogallol can be used.

For example, when T is titanium, a specific compound is tetraalkyl titanate (eg, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate),
Tetraethylene glycol titanate, triethanolamine titanate, titanium acetylacetonate, isopropyl trioctanoyl titanate, isopropyl trimethacryl titanate, isopropyl triacry titanate, isopropyl tri (butyl, methyl pyrophosphate) titanate, tetraisopropyl di (dilauryl) Examples thereof include phosphite) titanate, dimethacryloxyacetate titanate, diacryloxyacetate titanate, and di (dioctyl phosphate) ethylene titanate.

As the zirconium compound, the same compound as the above titanium compound can be used. Specific examples thereof include tetraalkyl zirconates such as tetraethyl zirconate and tetrabutyl zirconate, n-propyl zirconate, isopropyl zirconate, n-butyl zirconate, isobutyl zirconate, and zirconium acetylacetonate.

As the hafnium and thorium compounds, the same compounds as titanium and zirconium can be used.

Examples of the aluminate coupling agent include aluminum isopropylate, mono sec-butoxy aluminum diisopropylate, aluminum sec-butyrate, ethyl acetoacetate aluminum diisopropylate and aluminum tris (ethyl acetoacetate).
Can be exemplified.

Moreover, although the method for forming the coating film will not be described in detail,
In accordance with a conventional method, a coating material obtained by adding an ultraviolet absorber to a fluoropolymer or a coupling agent may be applied to the surface of the titanium material, dried, and baked if necessary.

Next, the reason why the addition amount of the ultraviolet absorber is limited will be described. When adding a UV absorber to a coating containing a fluoropolymer, if the addition amount is less than 0.1 wt%, the effect of improving the adhesion by adding the UV absorber is not sufficient, and 30 wt%
When it exceeds, the coating film is softened and the coating film hardness is lowered, so that the coating film is easily scratched. In addition, the surface is apt to become sticky, and there is a risk of blocking when the coating materials are stacked and stored. Therefore, the addition amount was set to 0.1 to 30 wt%, but a more preferable range is 0.5 considering the gloss and weather resistance.
~ 15wt%.

[Action]

In the present invention, the titanium material surface is coated with a coating material in which a fluorine-containing polymer is mixed with an ultraviolet absorber or a coupling agent, so that the surface of the titanium material is a fluorine-containing fluorine-containing or further coupling agent. Since the polymer film is formed, it is possible to suppress the ultraviolet light from reaching the interface between the coating film and titanium, and prevent the deterioration of the adhesiveness due to the atomic oxygen radicals O. As a result, the adhesiveness of the coating film can be maintained for a long time. When a coupling agent is contained, the OH group contained and the curing agent react with each other to form a coating film with excellent durability, and it is excellent due to the low surface energy of the fluoropolymer. Water and oil repellency of the coating film is obtained, which protects the titanium material from surface contamination,
Furthermore, since the coupling agent has an affinity for both the organic fluoropolymer and the titanium material, the coating film and titanium material adhere well.

〔Example〕

 Hereinafter, the present invention will be described based on examples.

Example 1 36.0 parts by weight of a fluoroolefin-vinyl ether polymer having an OH value of 53 mgKOH / gr was dissolved in a mixed solvent of 44.0 parts by weight of xylene and 10.0 parts by weight of methyl isobutyl ketone.
This was mixed with 9.8 parts by weight of blocked isocyanate and 0.2 parts by weight of a curing agent consisting of 5 × 10 ⁻⁴ parts by weight of dibutyltin dilaurate to prepare a transparent coating material having various ultraviolet absorber concentrations shown in Table 1. Then, this is applied by air spray to the titanium material surface that has been degreased with a strong alkaline degreasing agent so that the dry film thickness is 10 ± 5 μm, and dried at 180 ° C. for 20 minutes, and then used for the test. did. In addition, as a comparative example, a sample not using an ultraviolet absorber was also subjected to the same test.

In the test, initial adhesion, boiling water resistance, weather resistance and aging characteristics were examined. Here, each test was conducted as follows.

Gloss JIS Z 8741 Specular gloss measurement method -60 degree specular gloss-Hardness JIS K 5400 Pencil scratch test for paints

Durability test 500 hours or 2000 for weather resistance specimen
After the time, the peeling rate is calculated by the area ratio.

Table 1 shows the test results. As Comparative Example A, a case where no ultraviolet absorber is used is shown. According to Table 1, the coating films C, D, E, F and H in which the concentration of the ultraviolet absorber is within the range of the present invention have a higher weather resistance than Comparative Example A and coating films B and G outside the range of the present invention. Both hardness and glossiness show good results. As a result, the adhesion of the coating film is significantly improved by forming the coating film with a titanium polymer and a fluoropolymer coating added with an ultraviolet absorber. It is understood that it will be improved.

〔The invention's effect〕

As described above, according to the stain resistant titanium material and the method for producing the same according to the present invention, an ultraviolet absorber is provided on the titanium material surface,
Alternatively, since a fluoropolymer film containing a coupling agent is further formed, the adhesion between the coating film and the titanium material can be significantly improved, resulting in good corrosion resistance even in a highly corrosive environment, and for a long period of time. There is an effect that a titanium material having excellent stain resistance can be obtained.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuo Goto 186, Fingasaki Nagareyama City, Chiba Prefecture (72) Inventor Ryo Okamoto 1276, Mitsukizuki, Matsudo City, Chiba Prefecture (56) Bibliography Matsudo Dormitory (56) Reference JP-A-58-87144 (JP, A) JP-A 61-218203 (JP, A) JP-A 63-13741 (JP, A) JP-A 63-182143 (JP, A)

Claims (2)

[Claims] 1. A fluorine-based polymer film containing a coupling agent and an ultraviolet absorber made of any of a silane type, an aluminate type, a titanate type or a mixture thereof is formed on the surface of a titanium material. Characteristic stain resistant titanium material. 2. An ultraviolet absorber is added to the surface of a titanium material in an amount of 0.1 to 30 wt% of a fluorine-containing polymer containing a coupling agent composed of any one of a silane type, an aluminate type and a titanate type, or a mixture thereof. A method for producing a stain-resistant titanium material, which comprises applying the coating material as described above.