JP6186921B2 - Coated article - Google Patents

Description

The present invention relates to a coated article. More specifically, the present invention relates to a coated article having a layer made of a fluorine-containing polymer.

Fluorine-containing polymers such as tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer [PFA] have a low coefficient of friction and are excellent in properties such as non-adhesiveness, chemical resistance, and heat resistance. It is widely used for surface processing of food industry supplies, kitchen utensils such as frying pans and pans, household items such as irons, electrical industry supplies, and machine industry supplies.

Surface processing is performed by forming a layer made of a fluorine-containing polymer on a substrate. If the fluorine-containing polymer to be used is melt-processable such as PFA, a thick layer is produced by a general industrial production method. The surface of the resulting article can easily exhibit various properties of the fluorine-containing polymer.

For the purpose of improving the wear resistance and strength of the layer made of the fluorine-containing polymer, a filler may be added at the time of forming the layer.
For example, as a laminate excellent in scratch resistance, a primer layer containing aluminum oxide as a filler is formed on a substrate, and a melt-processable fluorine-containing polymer such as PFA and PTFE are formed on the primer layer. An intermediate layer made of aluminum oxide is formed, and a top coat layer made of PTFE is formed on the intermediate layer (see, for example, Patent Document 1).

In addition, a fluororesin coating film having a primer layer, an intermediate coat layer containing PFA, and a top coat layer containing a filler and diamond powder and glass flakes such as PFA is disclosed (for example, patents). Reference 2).

Further, a primer layer (A) composed of a fluoropolymer (a) and a heat-resistant resin, a fluorine-containing layer (B) composed of a melt-processable fluoropolymer (b) and a filler, and melt-processability A coated article in which a fluorine-containing layer (C) made of a fluorine-containing polymer (c) is laminated in this order is disclosed (for example, see Patent Documents 3 and 4).

Japanese Patent No. 2644380 JP 2006-297865 A International Publication No. 2004/041537 Pamphlet International Publication No. 2011/048965 Pamphlet

However, there is a need for coated articles that have better wear resistance than conventional coated articles. An object of the present invention is to provide a coated article excellent in wear resistance in view of the above-described present situation.

When the present inventors coat a substrate with a plurality of layers, a specific filler is selected, and the filler is added to a layer that is not the outermost layer to coat the substrate. The present inventors have found that a coated article having excellent wear properties can be obtained, and have completed the present invention.

That is, the present invention provides a substrate,
A primer layer (A) comprising a fluoropolymer (a) and a heat-resistant resin,
A fluorine-containing layer (B) comprising a melt-processable fluorine-containing polymer (b) and a filler, and
A fluorine-containing layer (C) comprising a melt-processable fluorine-containing polymer (c),
A coated article having
The heat resistant resin is at least one selected from the group consisting of polyamideimide resin, polyimide resin, polyethersulfone resin, polyetherimide resin, polyetheretherketone resin, aromatic polyester resin, and polyarylene sulfide resin. Yes,
The filler is at least one selected from the group consisting of silicon carbide, silicon nitride, alumina, diamond and fluorinated diamond,
The filler is a coated article characterized by being 0.01 to 40% by mass of the total amount of the melt-processable fluoropolymer (b) and the filler.

The heat-resistant resin is a polyethersulfone resin and one or both of a polyamideimide resin and a polyimide resin, and the polyethersulfone resin is a total of the polyethersulfone resin, the polyamideimide resin and the polyimide resin. It is preferable that it is 65-85 mass% of quantity.

The heat resistant resin is preferably 15 to 50% by mass of the total solid content of the heat resistant resin and the fluoropolymer (a).

The melt-processable fluoropolymer (c) is at least one selected from the group consisting of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer and a tetrafluoroethylene / hexafluoropropylene copolymer. Is preferred.

The fluoropolymer (a) is selected from the group consisting of a tetrafluoroethylene homopolymer, a modified polytetrafluoroethylene, a tetrafluoroethylene / hexafluoropropylene copolymer, and a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer. It is preferable that at least one selected.

The melt processable fluoropolymer (b) is at least one selected from the group consisting of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer and a tetrafluoroethylene / hexafluoropropylene copolymer. Is preferred.

The primer layer (A) has a thickness of 5 to 30 μm, the fluorine-containing layer (B) has a thickness of 1 to 90 μm, and the fluorine-containing layer (C) has a thickness of 1 to 90 μm. It is preferable that

Since the coated article of the present invention has the above-described configuration, it has excellent wear resistance and also has corrosion resistance. Such a coated article can be particularly suitably used for cooking utensils and kitchen utensils.

The present invention is described in detail below.

In the coated article of the present invention, a substrate, a primer layer (A), a fluorine-containing layer (B), and a fluorine-containing layer (C) are laminated in this order, and among these, the fluorine-containing layer (B) is melted. It consists of a workable fluoropolymer (b) and a filler, and the filler is at least one selected from the group consisting of silicon carbide, silicon nitride, alumina, diamond and fluorinated diamond.

Thus, the coated article of the present invention is excellent in wear resistance because the layer (B) which is not the outermost layer is composed of the melt-processable fluoropolymer (b) and the specific filler.

The coated article of the present invention comprises a substrate, a primer layer (A) formed on the substrate, a fluorine-containing layer (B) formed on the primer layer (A), and the fluorine-containing layer (B). It is preferable to have the fluorine-containing layer (C) formed in the above.

Hereinafter, the coated article of the present invention will be described in more detail with specific examples.

The substrate constituting the coated article of the present invention is not particularly limited, and examples thereof include metals such as iron, aluminum and copper and metals such as alloys thereof; nonmetallic inorganic materials such as enamel, glass and ceramics. Can be mentioned. Examples of the alloys include stainless steel. As said base material, a metal is preferable and aluminum or stainless steel is more preferable.

The base material may be subjected to a surface treatment such as a degreasing treatment or a surface roughening treatment, if necessary. The surface roughening treatment method is not particularly limited, and examples thereof include chemical etching with acid or alkali, anodization (alumite treatment), and sandblasting. In the surface treatment, the primer coating composition (i) for forming the primer layer (A) can be uniformly applied without causing repelling, and the base material and the primer coating film (Ap) For example, sand blasting is preferable, although it may be appropriately selected depending on the type of the base material, the primer coating composition (i), and the like.

The primer layer (A) constituting the coated article of the present invention is composed of a fluoropolymer (a) and a heat resistant resin.

The fluoropolymer (a) is a polymer having a fluorine atom that is directly bonded to the carbon atom constituting the main chain or side chain. The fluoropolymer (a) may be non-melt processable or melt processable.

The fluorinated polymer (a) is preferably obtained by polymerizing a fluorinated monoethylenically unsaturated hydrocarbon (I).

The above “fluorinated monoethylenically unsaturated hydrocarbon (I) (hereinafter also referred to as“ unsaturated hydrocarbon (I) ”)” is vinyl in which part or all of the hydrogen atoms are substituted by fluorine atoms. An unsaturated hydrocarbon having one group in the molecule is meant.

In the unsaturated hydrocarbon (I), a part or all of hydrogen atoms not substituted by fluorine atoms are halogen atoms other than fluorine atoms such as chlorine atoms and / or fluoroalkyl groups such as trifluoromethyl groups. It may be substituted by. However, the unsaturated hydrocarbon (I) excludes trifluoroethylene described later.

The unsaturated hydrocarbon (I) is not particularly limited, and examples thereof include tetrafluoroethylene [TFE], hexafluoropropylene [HFP], chlorotrifluoroethylene [CTFE], vinylidene fluoride [VdF], and vinyl fluoride [ VF] and the like, and one or more of these can be used.

The fluoropolymer (a) may be a homopolymer of the unsaturated hydrocarbon (I). Examples of the homopolymer of the unsaturated hydrocarbon (I) include, for example, tetrafluoroethylene homopolymer [TFE homopolymer], polychlorotrifluoroethylene [PCTFE], polyvinylidene fluoride [PVdF], polyvinyl fluoride [PVF]. ] Etc. are mentioned. TFE homopolymer is non-melt processable.

The fluoropolymer (a) is also a copolymer of at least one kind of the unsaturated hydrocarbon (I) and an unsaturated compound (II) that can be copolymerized with the unsaturated hydrocarbon (I). It may be.

In the present invention, the polymer obtained by polymerizing only one or more of the unsaturated hydrocarbons (I) can be used as the fluoropolymer (a). A polymer obtained by polymerizing only the seeds or two or more unsaturated compounds (II) cannot be used as the fluoropolymer (a). In this respect, the unsaturated compound (II) is different from the unsaturated hydrocarbon (I).

The unsaturated compound (II) is not particularly limited, and examples thereof include trifluoroethylene [3FH]; monoethylenically unsaturated hydrocarbons such as ethylene [Et] and propylene [Pr]. These can use 1 type (s) or 2 or more types.

The fluoropolymer (a) may be a copolymer of two or more unsaturated hydrocarbons (I). The copolymer of the two or more unsaturated hydrocarbons (I) and the copolymer of the at least one unsaturated hydrocarbon (I) and the unsaturated compound (II) are not particularly limited. Examples thereof include binary copolymers and ternary copolymers.

The binary copolymer is not particularly limited, and examples thereof include a VdF / HFP copolymer, an Et / CTFE copolymer [ECTFE], an Et / HFP copolymer, and the like.
The binary copolymer is also a TFE / HFP copolymer [FEP], a TFE / CTFE copolymer, a TFE / VdF copolymer, a TFE / 3FH copolymer, an Et / TFE copolymer [ETFE]. TFE copolymers such as TFE / Pr copolymer may be used. In the present specification, the “TFE copolymer” means a copolymer obtained by copolymerizing TFE and one or more monomers other than TFE. In the TFE copolymer, the proportion of other monomers other than TFE added to the TFE copolymer is usually 1 mass of the total mass of the TFE and the other monomers. % Is preferably exceeded.

Examples of the ternary copolymer include VdF / TFE / HFP copolymer.

The other monomer other than the TFE in the TFE copolymer may be another monomer (III) that can be copolymerized with the following TFE. The other monomer (III) is represented by the following general formula _{X (CF 2) m O n} CF = CF 2
(Wherein X represents —H, —Cl or —F, m represents an integer of 1 to 6, and n represents an integer of 0 or 1) (however, HFP excluding.), the following general formula _{C 3 F 7 O [CF (} CF 3) CF 2 O] p -CF = CF 2
(Wherein p represents an integer of 1 or 2), and the following general formula X (CF ₂ ) _q CY═CH ₂
(Wherein X is the same as above, Y represents —H or —F, and q represents an integer of 1 to 6). At least one selected from the group consisting of compounds represented by A seed monomer is preferred. These can use 1 type (s) or 2 or more types. Examples of such a TFE copolymer include TFE / perfluoro (alkyl vinyl ether) [PAVE] copolymer [PFA]. As PFA, PFA fluorinated by the method described in WO 2002/088227 pamphlet can also be used.

The fluoropolymer (a) may also be modified polytetrafluoroethylene [modified PTFE]. In the present specification, the “modified PTFE” means a product obtained by copolymerizing a small amount of a comonomer with TFE so as not to impart melt processability to the obtained copolymer. The small amount of the comonomer is not particularly limited, and examples thereof include HFP and CTFE among the unsaturated hydrocarbons (I), and 3FH among the unsaturated compounds (II). Among other monomers (III), PAVE, perfluoro (alkoxy vinyl ether), (perfluoroalkyl) ethylene and the like can be mentioned. One kind or two or more kinds of the small amount of comonomer can be used.

The ratio in which the small amount of the comonomer is added to the modified PTFE varies depending on the type thereof. For example, when PAVE, perfluoro (alkoxy vinyl ether) or the like is used, the TFE and the small amount of the comonomer are usually used. It is preferable that it is 0.001-1 mass% of the total mass with a weight body.

The fluoropolymer (a) may be one type or two or more types, and is a copolymer of one type of the unsaturated hydrocarbon (I) and the unsaturated hydrocarbon (I). Or a mixture of two or more of the above unsaturated hydrocarbon (I) copolymers.

Examples of the mixture include a mixture of a TFE homopolymer and the TFE copolymer, a mixture of two or more types of copolymers belonging to the TFE copolymer, and the like. Examples thereof include a mixture of TFE homopolymer and PFA, a mixture of TFE homopolymer and FEP, a mixture of TFE homopolymer, PFA and FEP, a mixture of PFA and FEP, and the like.

The fluoropolymer (a) is also a perfluoroalkyl group-containing ethylenically unsaturated monomer (IV) having a perfluoroalkyl group (hereinafter also referred to as “unsaturated monomer (IV)”). It may be obtained by polymerizing. The unsaturated monomer (IV) has the following general formula

(In the formula, Rf represents a perfluoroalkyl group having 4 to 20 carbon atoms, R ¹ represents —H or an alkyl group having 1 to 10 carbon atoms, and R ² represents an alkylene group having 1 to 10 carbon atoms. R ³ represents —H or a methyl group, R ⁴ represents an alkyl group having 1 to 17 carbon atoms, r represents an integer of 1 to 10, and s represents an integer of 0 to 10. It is expressed by.)
The fluoropolymer (a) may be a homopolymer of the unsaturated monomer (IV), or the unsaturated monomer (IV) and the unsaturated monomer (IV). ) And a copolymer with the monomer (V) that can be copolymerized.

The monomer (V) is not particularly limited, and examples thereof include cyclohexyl (meth) acrylate, benzyl (meth) acrylate, polyethylene glycol di (meth) acrylate, N-methylolpropane acrylamide, and (meth) acryl. (Meth) acrylic acid derivatives such as acid amides and alkyl esters of (meth) acrylic acid having an alkyl group having 1 to 20 carbon atoms; ethylene, vinyl chloride, vinyl fluoride, styrene, α-methylstyrene, p-methyl Substituted or unsubstituted ethylene such as styrene; alkyl vinyl ethers having 1 to 20 carbon atoms in the alkyl group; vinyl ethers such as halogenated alkyl vinyl ethers having 1 to 20 carbon atoms in the alkyl group; Vinyl ketones such as vinyl alkyl ketones of ˜20; Aliphatic unsaturated polycarboxylic acids and derivatives thereof such as phosphate; butadiene, isoprene, polyenes such as chloroprene.

The fluoropolymer (a) can be obtained, for example, by using a conventionally known polymerization method such as emulsion polymerization.

As said fluoropolymer (a), at least 1 sort (s) selected from the group which consists of a TFE homopolymer, a modified PTFE, and the said TFE type copolymer from the point which the coated article obtained is excellent in corrosion resistance and water vapor resistance. Polymers are preferred. The TFE copolymer is preferably at least one copolymer selected from the group consisting of FEP and PFA.

From the above, the fluoropolymer (a) is preferably at least one polymer selected from the group consisting of TFE homopolymer, modified PTFE, FEP and PFA.

As said fluoropolymer (a), the thing containing a TFE type | system | group copolymer from the point which the adhesiveness of a primer layer (A) and a layer (B) is excellent in the obtained coated article is preferable. Since the coated article having excellent adhesion between the primer layer (A) and the layer (B) is excellent in water vapor resistance, the occurrence of coating film defects such as blisters can be suppressed even in the presence of water vapor. Examples of the fluoropolymer (a) containing a TFE copolymer include TFE homopolymer alone, PFA alone, a mixture of TFE homopolymer and FEP, a mixture of TFE homopolymer and PFA, and modified PTFE and FEP. Or a mixture of modified PTFE and PFA is preferred. In addition, the fluoropolymer (a) in the primer layer (A) is a TFE because the resulting coated article has excellent corrosion resistance and water vapor resistance, and excellent adhesion between the primer layer (A) and the layer (B). Homopolymer alone, PFA alone, a mixture of TFE homopolymer and PFA, or a mixture of TFE homopolymer and FEP, preferably TFE homopolymer alone or a mixture of TFE homopolymer and FEP Is more preferable.

The heat-resistant resin that can constitute the primer layer (A) is usually a resin that is recognized as having heat resistance, and is preferably a resin having a continuous usable temperature of 150 ° C. or higher. However, the above-mentioned fluoropolymer (a) is excluded as the heat-resistant resin.

The heat-resistant resin is not particularly limited. For example, from the group consisting of polyamideimide resin, polyimide resin, polyethersulfone resin, polyetherimide resin, polyetheretherketone resin, aromatic polyester resin, and polyarylene sulfide resin. It is preferable that it is at least one selected resin.

The polyamide-imide resin [PAI] is a resin composed of a polymer having an amide bond and an imide bond in the molecular structure. The PAI is not particularly limited. For example, a reaction between an aromatic diamine having an amide bond in the molecule and an aromatic tetravalent carboxylic acid such as pyromellitic acid; an aromatic trivalent carboxylic acid such as trimellitic anhydride; It consists of a high molecular weight polymer obtained by a reaction with a diamine such as 4,4-diaminophenyl ether or a diisocyanate such as diphenylmethane diisocyanate; a reaction between a dibasic acid having an aromatic imide ring in the molecule and a diamine. Examples thereof include resins. As said PAI, what consists of a polymer which has an aromatic ring in a principal chain from the point which is excellent in heat resistance is preferable.

The polyimide resin [PI] is a resin made of a polymer having an imide bond in the molecular structure. The PI is not particularly limited, and examples thereof include a resin made of a high molecular weight polymer obtained by a reaction of an aromatic tetravalent carboxylic anhydride such as pyromellitic anhydride. As said PI, what consists of a polymer which has an aromatic ring in a principal chain from the point which is excellent in heat resistance is preferable.

The polyethersulfone resin [PES] has the following general formula:

It is resin which consists of a polymer which has a repeating unit represented by these. The PES is not particularly limited, and examples thereof include a resin made of a polymer obtained by polycondensation of dichlorodiphenyl sulfone and bisphenol.

The above heat-resistant resin has excellent adhesion to the substrate, has sufficient heat resistance even at the firing temperature when forming a coated article, and the resulting coated article has excellent corrosion resistance and water vapor resistance Therefore, at least one resin selected from the group consisting of PAI, PI and PES is preferable. Each of PAI, PI, and PES may be composed of one type or two or more types.

The heat resistant resin is more preferably at least one resin selected from the group consisting of PAI and PI from the viewpoint of excellent adhesion to the substrate and heat resistance.

The heat resistant resin is preferably composed of PES and at least one resin selected from the group consisting of PAI and PI from the viewpoint of excellent corrosion resistance and water vapor resistance. That is, the heat resistant resin may be a mixture of PES and PAI, a mixture of PES and PI, or a mixture of PES, PAI, and PI. The heat-resistant resin is particularly preferably a mixture of PES and PAI.

When the heat-resistant resin is composed of PES and at least one resin selected from the group consisting of PAI and PI, the PES is a total amount of the PES and PAI and / or PI. It is preferable that it is 65-85 mass%. More preferably, it is 70-80 mass%.

As content of the said heat resistant resin, it is preferable that it is 10-50 mass% of solid content total amount of this heat resistant resin and the said fluoropolymer (a), and it is more preferable that it is 15-50 mass%. preferable. More preferably, it is 10-40 mass%, Most preferably, it is 15-30 mass%. In the present specification, the “solid content” means a solid at 20 ° C. In the present specification, the “total amount of solid content of the heat-resistant resin and the fluoropolymer (a)” means a temperature of 80 to 100 ° C. after the coating composition (i) for primer is applied on a substrate. Means the total mass of the heat-resistant resin and the fluoropolymer (a) in the residue after drying at 380 to 400 ° C. for 45 minutes.

The primer layer (A) is usually formed on a substrate. The primer layer (A) is, for example, a primer coating composition (i) described later composed of a fluoropolymer (a) and a heat-resistant resin is applied onto a substrate, dried as necessary, It is obtained by firing. The primer layer (A) thus obtained has a difference in surface tension between the fluoropolymer (a) and the heat-resistant resin, so that the fluoropolymer (a) floats during firing. The fluoropolymer (a) is mainly disposed on the surface side at a distance from the substrate, and the heat-resistant resin is mainly disposed on the substrate side.

When the primer layer (A) is composed of the fluoropolymer (a) and the heat-resistant resin, the heat-resistant resin has adhesiveness to the base material, and therefore has excellent adhesion to the base material. The primer layer (A) is also excellent in adhesion to the layer (B) because the fluoropolymer (a) has an affinity for the melt-processable fluoropolymer (b). Thus, when the said primer layer (A) consists of the said fluoropolymer (a) and the said heat resistant resin, it has the outstanding adhesiveness with respect to both a base material and a layer (B). is there.

It is preferable that the said primer layer (A) consists of a polymer component and the additive mentioned later. The primer layer (A) is preferably one in which the polymer component is a fluoropolymer (a) and a heat resistant resin. In the present specification, the “primer layer (A) is a polymer component comprising a fluoropolymer (a) and a heat-resistant resin” means that the polymer in the primer layer (A) is a fluoropolymer (a ) And heat resistant resin only. The primer layer (A) has an excellent adhesion with respect to both the base material and the layer (B) described later efficiently because the polymer component is a fluoropolymer (a) and a heat-resistant resin. I have it.

The primer layer (A) is one in which the polymer component is a fluoropolymer (a) and a heat-resistant resin from the viewpoint of efficiently exhibiting excellent adhesion to both the base material and the layer (B). However, from the viewpoint that the corrosion resistance and water vapor resistance of the coated article can be further improved, the coated article may be made of another resin in addition to the fluoropolymer (a) and the heat resistant resin. Examples of other resins include those described later.

The primer layer (A) preferably has a thickness of 5 to 30 μm. If the film thickness is too thin, pinholes are likely to occur, and the corrosion resistance of the coated article may be reduced. If the film thickness is too thick, cracks are likely to occur, and the steam resistance of the coated article may be reduced. The upper limit with more preferable film thickness of the said primer layer (A) is 20 micrometers.

As the melt processable fluoropolymer (b) constituting the layer (B), those having melt processability among the above-mentioned fluoropolymers (a) can be used. In the melt-processable fluoropolymer (b), the resulting layer (B) is excellent in adhesion between the primer layer (A) and the layer (C), and the resulting coated article is resistant to corrosion and water vapor. From the viewpoint of superiority, those having a melting point of 150 to 350 ° C. and a melt viscosity at a temperature 50 ° C. higher than the melting point are preferably 10 ⁶ (Pascal · second) or less, and preferably the above-mentioned TFE copolymer. . The melt-processable fluoropolymer (b) may be one type or two or more types. The melt-processable fluoropolymer (b) is more preferably at least one fluoropolymer selected from the group consisting of PFA and FEP. The melt-processable fluoropolymer (b) may be either PFA or FEP alone or a mixture thereof. From the viewpoint of excellent heat resistance, the melt-processable fluoropolymer (b) is more preferably PFA.

The layer (B) is preferably laminated on the primer layer (A). Moreover, it is preferable that the below-mentioned layer (C) is laminated | stacked on the said layer (B).

The layer (B) is preferably formed from a paint composed of a melt-processable fluoropolymer (b). The coating material may be a powder coating material or a liquid coating material such as a water-based coating material, but does not require a drying step, and it is easy to obtain a thick coating film with a small number of coatings, and wear resistance. It is preferable that it is a powder coating material (ii) at the point which is also excellent.

The layer (B) includes at least one filler selected from the group consisting of silicon carbide, silicon nitride, alumina, diamond, and fluorinated diamond. The filler is preferably at least one selected from the group consisting of silicon carbide and silicon nitride.

Fluorinated diamond can be obtained by fluorinating diamond. The fluorination of diamond can be performed, for example, by a known method disclosed in Summary of the 26th Fluorine Chemistry Discussion Meeting, issued on November 14, 2002, p24-25. That is, diamond may be sealed in a reactor made of a material having corrosion resistance to fluorine, such as nickel or an alloy containing nickel, and fluorinated by introducing fluorine gas.

The filler preferably has an average particle size of 0.01 to 100 μm, more preferably 0.05 to 50 μm.

The said filler is 0.01-40 mass% with respect to the total amount of a melt-processable fluoropolymer (b) and a filler. Preferably it is 0.05-30 mass%, More preferably, it is 0.1-10 mass%. If the amount of the filler is too large, the corrosion resistance is lowered, and if the amount of the filler is too small, sufficient wear resistance cannot be obtained.

The layer (B) further comprises wood powder, quartz sand, carbon black, clay, talc, corundum, quartzite, tourmaline, coral, germanium, extender pigment, glittering flat pigment, scaly pigment, glass, various reinforcing materials. Various fillers, conductive fillers and the like may be included.

The layer (B) preferably has a thickness of 1 to 90 μm. If the film thickness is too thin, the resulting coated article may not have sufficient wear resistance. If the film thickness is too thick, moisture transmitted from the layer (B) is difficult to escape, and the water resistance of the coated article may be reduced. The minimum with a more preferable film thickness of the said layer (B) is 5 micrometers, and a more preferable upper limit is 30 micrometers.

As the melt-processable fluoropolymer (c) constituting the layer (C), those having melt processability among the above-mentioned fluoropolymers (a) can be used.

As the above-mentioned melt-processable fluoropolymer (c), the film-forming property is excellent, the obtained layer (C) is excellent in adhesion to the above-mentioned layer (B), and the obtained coated article is resistant. From the point of being excellent in abrasion, those having the same kind as the above-mentioned melt-processable fluoropolymer (b) are preferable. Moreover, what has a melting point of 150-350 degreeC and whose melt viscosity in the temperature 50 degreeC higher than melting | fusing point is 10 < ⁶ > (pascal second) or less is preferable. An example of such a melt-processable fluoropolymer (c) is a TFE copolymer. The melt-processable fluoropolymer (c) is preferably at least one polymer selected from the group consisting of PFA and FEP from the viewpoint of excellent heat resistance, non-adhesiveness and film-forming property. The melt processable fluoropolymer (c) may be PFA alone, FEP alone, or a mixture of PFA and FEP. As the melt-processable fluoropolymer (c), PFA is more preferable from the viewpoint of excellent heat resistance.

In the coated article of the present invention, the layer (C) is preferably formed on the layer (B), and is baked at a temperature equal to or higher than the melting point of the melt-processable fluoropolymer (c). Preferably there is.

The layer (C) is preferably formed from a paint composed of a melt-processable fluoropolymer (c). The coating material may be a powder coating material or a liquid coating material such as a water-based coating material. However, it is easy to obtain a thick coating film with a small number of coatings and does not require a drying process. In view of the excellent quality, the powder coating material (iii) is preferable.

The layer (C) may contain a filler for the purpose of imparting characteristics to the resulting coated article, improving physical properties, increasing the amount, and the like. Examples of the above properties and physical properties include strength, durability, weather resistance, flame resistance, and design properties. When what has a glittering feeling is used as a filler, the coated article of this invention has a favorable glittering feeling.

The filler is not particularly limited, for example, wood powder, quartz sand, carbon black, clay, talc, diamond, fluorinated diamond, corundum, silica, boron nitride, boron carbide, silicon carbide, fused alumina, tourmaline, Examples include soot, germanium, extender pigments, glittering flat pigments, scaly pigments, glass, glass powder, mica powder, metal powder, various reinforcing materials, various fillers, and conductive fillers. As the filler, a glitter filler is preferred when the fluorine-containing laminate of the present invention is required to have glitter. The “brilliant filler” is a filler capable of imparting glitter to the resulting fluorine-containing laminate.

Since the layer (B) contains a filler, the coated article of the present invention exhibits unexpectedly excellent wear resistance even if the layer (C) does not contain a filler. The layer (C) preferably does not contain a filler from the viewpoint of improving corrosion resistance.

The powder coating material (iii) is preferably composed of a polymer component and an additive. The powder coating material (iii) is preferably one in which the polymer component is a melt-processable fluoropolymer (c). In the present specification, the above-mentioned “powder coating (iii) is a polymer component of the melt-processable fluoropolymer (c)” means that the polymer in the powder coating (iii) is a melt-processable fluorine-containing polymer. It means that it is only a polymer (c). The layer (C) obtained by the polymer component of the powder coating (iii) being a melt-processable fluoropolymer (c) has excellent adhesion to the layer (B). It is.

The layer (C) preferably has a thickness of 1 to 90 μm. If the film thickness is too thin, the corrosion resistance of the coated article may be reduced. If the film thickness is too thick, when the coated article is in the presence of water vapor, the water vapor tends to remain in the coated article, and the water vapor resistance may be poor. The minimum with a more preferable film thickness of the said layer (C) is 10 micrometers, and a more preferable upper limit is 60 micrometers.

The primer layer (A) has a thickness of 5 to 30 μm, the layer (B) has a thickness of 1 to 90 μm, and the layer (C) has a thickness of 1 to 90 μm. It is one of the preferred embodiments of the present invention to be 1 to 90 μm.

The stacking order of the layers constituting the coated article of the present invention is not particularly limited, but the base material, the primer layer (A), the layer (B), and the layer (C) are stacked in this order. Is preferred. Thereby, both wear resistance and corrosion resistance can be more effectively achieved.
Usually, the coated article of the present invention has no other layers between the base material, the primer layer (A), the layer (B) and the layer (C). Further, another layer may be interposed between the primer layer (A) and the layer (B) or between the layer (B) and the layer (C).

In the coated article of the present invention, when the substrate, the primer layer (A), the layer (B), and the layer (C) are laminated in this order, the upper surface of the primer layer (A), and / or The upper surface of the layer (B) may be printed with characters, drawings and the like.

As described above, the coated article of the present invention only needs to have the primer layer (A), the layer (B) and the layer (C), and a layer is further provided on the layer (C). However, the layer (C) is preferably the outermost layer. By placing the layer (C), which greatly contributes to the improvement of wear resistance, in the outermost layer that is particularly required to have wear resistance in the use environment, the effect relating to wear resistance of the present invention is more remarkably exhibited. Can do.

The coated article of the present invention is, for example, a step (1) of forming a primer coating film (Ap) by applying a primer coating composition (i) on a substrate, on the primer coating film (Ap), Step (2) of forming a coating film (Bp) by applying a paint (ii) comprising a melt-processable fluoropolymer (b), and a melt-processable fluoropolymer (c) on the coating film (Bp) Step (3) of forming a coating film (Cp) by applying a coating (iii) made of a), and a coating film comprising a primer coating film (Ap), a coating film (Bp), and a coating film (Cp) By firing the laminate, it can be produced by a method including a step (4) of forming a coated article comprising a substrate, a primer layer (A), a layer (B) and a layer (C).

The said process (1) is a process of forming a primer coating film (Ap) by apply | coating the primer coating composition (i) on a base material.

In the step (1), the primer coating composition (i) is preferably composed of a fluoropolymer (a) and a heat resistant resin. The fluorine-containing polymer (a) and the heat resistant resin are as described above. The primer coating composition (i) may be liquid or powder. When the primer coating composition (i) is in a liquid state, it is composed of a liquid medium together with the fluoropolymer (a) and a heat-resistant resin. The liquid medium is usually composed of water and / or an organic liquid. In the present specification, the “organic liquid” means an organic compound that is liquid at a room temperature of about 20 ° C.

When the liquid medium of the primer coating composition (i) is mainly composed of an organic liquid, the heat-resistant resin and the fluoropolymer (a) are dispersed in the liquid medium as particles, and / or Or it melt | dissolves in the said liquid medium. As said organic liquid, a conventionally well-known organic solvent etc. may be used, may be used independently, and may use 2 or more types together.

When the liquid medium of the primer coating composition (i) is mainly composed of water, the heat-resistant resin is dispersed as particles in the liquid medium, and the fluoropolymer (a) is: Dispersed as particles in the liquid medium.

The primer coating composition (i) is usually a surfactant for the purpose of dispersing and stabilizing the particles comprising the fluoropolymer (a) when the liquid medium is mainly composed of water. Is added. A conventionally known surfactant may be used as the surfactant. In the said primer coating composition (i), the said organic liquid can also be used together with the said surfactant for the purpose of carrying out the dispersion stabilization of the particle | grains which consist of a fluoropolymer (a).

The primer coating composition (i) may also be an organosol obtained by the method described in JP-B-49-17017.

The primer coating composition (i) is preferably a liquid from the viewpoint of excellent adhesion to the substrate, and more preferably a liquid medium mainly composed of water from the viewpoint of environmental problems.

The primer coating composition (i), together with the fluoropolymer (a) and the heat-resistant resin, further improves the coating workability and the corrosion resistance and water vapor resistance of the resulting coated article. You may consist of an additive mentioned above.

From the point which can improve the corrosion resistance and water vapor resistance of the coated article, the primer coating composition (i) is composed of the fluorine-containing polymer (a) and the heat-resistant resin, as well as other resins described above. It may be.

The method for applying the primer coating composition (i) on the substrate is not particularly limited, and when the primer coating composition (i) is liquid, for example, spray coating, roll coating, or doctor blade coating. Dip (immersion) coating, impregnation coating, spin flow coating, curtain flow coating, and the like, and spray coating is particularly preferable. In the case where the primer coating composition (i) is a powder, electrostatic coating, fluid dipping method, rolining method and the like can be mentioned, among which electrostatic coating is preferable.

After application of the primer coating composition (i) in the step (1), baking may be performed before performing the step (2), or baking may not be performed. Moreover, when the said coating composition (i) for primers is liquid, after the said application | coating, it may dry further and does not need to dry.

In the step (1), the drying is preferably performed at a temperature of 70 to 300 ° C. for 5 to 60 minutes. The firing is preferably performed at a temperature of 260 to 410 ° C. for 10 to 30 minutes.

When the primer coating composition (i) is in a liquid state, in the step (1), it is preferable to dry after coating on the substrate. Moreover, since baking of a coating film laminated body is performed in the below-mentioned process (4), it is preferable not to perform baking.

When the primer coating composition (i) is a powder, in the step (1), it is preferable to perform baking after coating on the substrate.

The primer coating film is formed by applying the primer coating composition (i) on a substrate and then drying or baking as necessary. The primer coating film becomes a primer layer in the resulting coated article.

The step (2) is a step of forming the coating film (Bp) by applying the paint (ii) made of the melt-processable fluoropolymer (b) on the primer coating film.

The paint (ii) in the step (2) may be a powder paint containing particles made of the melt-processable fluoropolymer (b), or may be a liquid paint such as an aqueous paint. A powder coating is preferred in that a drying step is unnecessary and it is easy to obtain a thick coating film with a small number of coatings. When the paint (ii) is a liquid paint, it is preferable that particles made of PFA are dispersed in a liquid medium, and the aqueous paint is made by dispersing particles made of PFA mainly in an aqueous medium made of water. Is more preferable.

The average particle diameter of the particles comprising the melt-processable fluoropolymer (b) in the paint (ii) is preferably 0.01 to 40 μm in the case of a liquid paint and 1 to 50 μm in the case of a powder paint.

The paint (ii) includes at least one filler selected from the group consisting of silicon carbide, silicon nitride, alumina, diamond and fluorinated diamond, and at least one selected from the group consisting of silicon carbide and silicon nitride. Preferably it contains seeds. When the coating material (ii) contains a specific filler, the wear resistance of the coated article is excellent. The powder coating (ii) further includes wood powder, quartz sand, carbon black, clay, talc, corundum, quartzite, tourmaline, coral, germanium, extender pigment, bright flat pigment, scaly pigment, glass, various types Reinforcing materials, various fillers, conductive fillers and the like may be included.

The paint (ii) may also contain a small amount of PTFE (TFE homopolymer, modified PTFE) together with the melt-processable fluoropolymer (c) for the purpose of refining the spherulites. In this case, the content of PTFE is preferably 0.01 to 10.0% by mass with respect to PFA.

The method for applying the paint (ii) on the primer coating film is not particularly limited, and examples thereof include the same method as the method for applying the primer coating composition (i). When the paint (ii) is a powder paint, electrostatic coating is preferred.

In the said process (2), after apply | coating coating material (ii) on a base material, you may dry or bake. The drying or firing in the step (2) is preferably performed under the same conditions as the drying or firing in the step (1).

Usually, it is preferable not to perform baking after coating the paint (ii) on the primer coating film. This is because all the coating films can be fired at the same time when firing the coating film laminate in the step (4) described below.

The coating film (Bp) is formed by applying the paint (ii) on the primer coating film and then drying or baking as necessary. The said coating film (Bp) becomes a layer (B) in the coated article obtained.

The step (3) is a step of forming the coating film (Cp) by applying a paint (iii) made of the melt-processable fluoropolymer (c) on the coating film (Bp).

The paint (iii) in the above step (3) may be a powder paint containing particles made of the melt-processable fluoropolymer (c), or a liquid paint such as an aqueous paint, but is dried. A powder coating material is preferable in that a process is unnecessary and it is easy to obtain a thick coating film with a small number of coatings. When the paint (iii) is a liquid paint, it is preferable that particles made of the melt-processable fluoropolymer (c) are dispersed in a liquid medium, and particles made of the melt-processable fluoropolymer (c). Is more preferably an aqueous paint dispersed in an aqueous medium mainly composed of water.

The average particle diameter of the particles comprising the melt-processable fluoropolymer (c) in the paint (iii) is preferably 0.01 to 40 μm in the case of a liquid paint and 1 to 50 μm in the case of a powder paint.

The paint (iii) may contain a filler for the purpose of imparting properties to the coated article to be obtained, improving physical properties, and increasing the amount. Examples of the above properties and physical properties include strength, durability, weather resistance, flame resistance, and design properties. Examples of the filler include those described above.

The paint (iii) may also contain a small amount of PTFE (TFE homopolymer, modified PTFE) together with the melt-processable fluoropolymer (c) for the purpose of refining the spherulites. In this case, the content of PTFE is preferably 0.01 to 10.0% by mass with respect to PFA.

Moreover, it is preferable that the said coating material (iii) does not contain a color pigment. Since colored pigments are generally considered to be a cause of worsening corrosion resistance, if the paint (iii) does not contain color pigments, the resulting coated article has better corrosion resistance and water vapor resistance. It will be a thing.

The method for applying the paint (iii) on the coating film (Bp) is not particularly limited, and examples thereof include the same method as the method for applying the primer coating composition (i). When the paint (iii) is a powder paint, electrostatic coating is preferred.

The coating film (Cp) may be formed by drying or baking as necessary after the coating. The drying or firing in the step (3) is preferably performed under the same conditions as the drying or firing in the step (1). The coating film (Cp) becomes a layer (C) in the resulting coated article.

In the step (4), the base film, the primer layer (A), and the layer (B) are formed by firing a coating film laminate including the primer coating film (Ap), the coating film (Bp), and the coating film (Cp). And a coated article comprising the layer (C).

The firing in the step (4) is preferably performed under the same conditions as the firing in the steps (1) to (3).

The said manufacturing method has the process of printing a character, drawing, etc. after the process (1) which forms the said primer coating film (Ap), or the process (2) which forms the said coating film (Bp). It may be a thing. The said character, drawing, etc. are the character, line, etc. which show the quantity of water, for example, when a coated article is a rice cooker.

The printing method is not particularly limited, and examples thereof include pad transfer printing. It does not specifically limit as printing ink used for the said printing, For example, the composition which consists of PES, a TFE homopolymer, and a titanium oxide is mentioned.

The coated article of the present invention can be used for applications utilizing the non-adhesiveness, heat resistance, slipperiness, etc. of the fluoropolymer, such as frying pans, pressure cookers, Cooking utensils such as pans, grill pans, rice cookers, ovens, hot plates, baking molds, knives, gas tables; kitchen supplies such as electric pots, ice trays, molds, range hoods; kneading rolls, rolling rolls, conveyors, hoppers Industrial parts such as office automation (OA) rolls, OA belts, OA separation nails, papermaking rolls, film production calendar rolls, molds, molds, plywood, makeup, etc. Molding mold release such as release plate for plate production, industrial containers (especially for the semiconductor industry), etc. are mentioned. Tools such as irons; Household items such as irons, scissors, knives; metal foils, electric wires, food processing machines, packaging machines, sliding machines for textile machines, sliding parts for cameras and watches, pipes, valves, bearings, etc. Examples include parts, snow shovels, plows, and chutes.
Among these, it can be suitably used for cooking utensils and kitchen utensils, and can be particularly suitably used for rice cookers.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. “%” And “part” represent mass% and mass part, respectively.

Production Example 1 Preparation of Polyethersulfone Resin Aqueous Dispersion 60 parts of a polyethersulfone resin [PES] having a number average molecular weight of about 24,000 and 60 parts of deionized water were completely pulverized in a ceramic ball mill. Stir for about 10 minutes. Subsequently, 180 parts of N-methyl-2-pyrrolidone (hereinafter referred to as NMP) was added, and further pulverized for 48 hours to obtain a dispersion. The obtained dispersion was further pulverized with a sand mill for 1 hour to obtain a PES aqueous dispersion having a PES concentration of about 20%. The average particle diameter of the particles composed of PES in the PES aqueous dispersion was 2 μm.

Production Example 2 Preparation of Polyamideimide Resin Aqueous Dispersion Polyamideimide resin [PAI] varnish (containing 71% NMP) having a solid content of 29% was poured into water to precipitate PAI. This was pulverized for 48 hours in a ball mill to obtain an aqueous PAI dispersion. The solid content of the obtained PAI aqueous dispersion was 20%, and the average particle size of PAI in the PAI aqueous dispersion was 2 μm.

Production Example 3 Preparation of Primer Coating Composition (i) The PES aqueous dispersion obtained in Production Example 1 and the PAI aqueous dispersion obtained in Production Example 2 were mixed with the solid content of PES and PAI. Mix to 75% of the total amount, and add tetrafluoroethylene homopolymer [TFE homopolymer] aqueous dispersion (average particle size 0.28 μm, solid content 60%, polyether nonionic interface as dispersant) Active agent (polyoxyethylene tridecyl ether) 6% with respect to the TFE homopolymer) so that the PES and PAI are 25% of the total solid content of the PES, PAI and TFE homopolymer. In addition, methylcellulose as a thickener was added in an amount of 0.7% based on the solid content of the TFE homopolymer, and a nonionic surfactant (polyoxyethylene) was added as a dispersion stabilizer. The emissions nonylphenyl ether) was added 6% based on the solids content of the TFE homopolymer, to obtain a 34% solids aqueous dispersion of TFE homopolymer.

Example 1
After degreasing the surface of the aluminum plate (A-1050P) with acetone, sand blasting is performed so that the surface roughness Ra value measured according to JIS B 1982 is 2.0 to 3.0 μm, and the surface is roughened. Turned into. After removing the dust on the surface by air blowing, the primer coating composition (i) obtained in Production Example 3 was subjected to RG-2 type gravity spray gun (trade name, Using anest Iwata Co., Ltd. nozzle diameter 1.0 mm, spray coating was performed at a spraying pressure of 0.2 MPa. The obtained coating film on the aluminum plate was dried at 80 to 100 ° C. for 15 minutes and cooled to room temperature. On the obtained primer coating film, PFA (trade name: ACX-34, manufactured by Daikin Industries, Ltd.) and silicon carbide as a filler (5% of the total amount of PFA and silicon carbide, average particle diameter 7 μm) The powder coating (ii) contained was electrostatically coated under the conditions of an applied voltage of 50 KV and a pressure of 0.08 MPa so that the film thickness after firing was 10 μm. On top of this, PFA (trade name: ACX-34, manufactured by Daikin Industries, Ltd.) is electrostatically coated under conditions of an applied voltage of 50 KV and a pressure of 0.08 MPa so that the film thickness after firing is 40 μm. Firing was performed at 380 ° C. for 20 minutes to obtain a test coating plate. In the obtained test coated plate, a primer layer (undercoat layer), a layer made of PFA and a filler (intercoat layer), and a PFA layer (overcoat layer) were formed on an aluminum plate.

(Evaluation method)
The following evaluation was performed about the coating film of the obtained coating plate for a test.

The film thickness was measured using a high-frequency film thickness meter (trade name: LZ-300C, manufactured by Kett Science Laboratory).

Wear resistance test (Taber abrasion test)
The abrasion resistance of the obtained test coating plate was measured using a rotary ablation tester manufactured by Toyo Seiki Co., Ltd. under a load of 1 kg and a wear wheel CS-10 under conditions of 500 revolutions.

Examples 2 to 5 and Comparative Example 1
A test coating plate was obtained in the same manner as in Example 1 except that instead of silicon carbide, a powder coating containing the filler shown in Table 1 in the amount shown in Table 1 was used in the powder coating (ii). . About the obtained coating plate for a test, the coating-film physical property was evaluated similarly to Example 1.

Comparative Example 2
A test coated plate was obtained in the same manner as in Example 1 except that the powder paint (ii) was not applied. In the test coated plate, a primer layer (undercoat layer) and a PFA layer (overcoat layer) were formed on an aluminum plate. About the obtained coating plate for a test, the coating-film physical property was evaluated similarly to Example 1.

The results are shown in Table 1.

Since the coated article of the present invention has the above-described configuration, it is excellent in both wear resistance and corrosion resistance, and can be particularly suitably used for coated articles such as cooking utensils and kitchen utensils.

Claims (6)

Base material,
A primer layer (A) comprising a fluoropolymer (a) and a heat-resistant resin,
A fluorine-containing layer (B) comprising a melt-processable fluorine-containing polymer (b) and a filler, and
A fluorine-containing layer (C) comprising a melt-processable fluorine-containing polymer (c),
A coated article having
The heat-resistant resin is at least one selected from the group consisting of a polyamideimide resin, a polyimide resin, a polyethersulfone resin, a polyetherimide resin, a polyetheretherketone resin, an aromatic polyester resin, and a polyarylene sulfide resin. Yes,
The melt processable fluoropolymer (b) is at least one selected from the group consisting of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer and a tetrafluoroethylene / hexafluoropropylene copolymer,
The filler is at least one selected from the group consisting of silicon carbide and silicon nitride,
The said filler is 0.01-40 mass% of the total amount of a melt-processable fluoropolymer (b) and a filler, The coated article characterized by the above-mentioned. The heat-resistant resin is a polyethersulfone resin and one or both of a polyamideimide resin and a polyimide resin, and the polyethersulfone resin is a total amount of the polyethersulfone resin, the polyamideimide resin and the polyimide resin. The coated article according to claim 1, which is 65 to 85% by mass. The coated article according to claim 1 or 2, wherein the heat resistant resin is 15 to 50 mass% of the total solid content of the heat resistant resin and the fluoropolymer (a). The melt processable fluoropolymer (c) is at least one selected from the group consisting of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer and a tetrafluoroethylene / hexafluoropropylene copolymer. The coated article according to 1, 2 or 3. The fluoropolymer (a) is selected from the group consisting of a tetrafluoroethylene homopolymer, a modified polytetrafluoroethylene, a tetrafluoroethylene / hexafluoropropylene copolymer, and a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer. The coated article according to claim 1, 2, 3 or 4, wherein the coated article is at least one kind. The primer layer (A) has a film thickness of 5 to 30 μm,
The fluorine-containing layer (B) has a thickness of 1 to 90 μm,
Fluorine-containing layer (C) according to claim 1, 2, 3, 4 or 5 SL placing the coated article thickness is 1～90Myuemu.