KR101585356B1 - Fluororesin laminate and method for manufacturing same - Google Patents

Abstract

A fluorine-containing laminate free from coating defects and excellent in corrosion resistance, and a process for producing the same. The present invention relates to a process for producing a fluorine-containing fluorine-containing polymer (A), which comprises a base material, a layer (B) formed of a powder coating (ii) containing a primer layer (A), a melt- A fluorine-containing laminate having a layer (C) formed of a liquid coating material (iii), wherein the average particle diameter of the powder coating material (ii) is 5 to 30 占 퐉 and the average particle diameter of the particles Containing layered product having an average particle diameter of 0.01 to 1.0 탆.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a fluorine-

The present invention relates to a fluorine-containing laminate and a method for producing the same.

The fluorine-containing polymer such as tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer [PFA] has a low coefficient of friction and is excellent in properties such as non-tackiness, chemical resistance and heat resistance, Kitchen utensils such as pots, kitchen utensils such as pots, household appliances such as irons, electrical appliances, and mechanical industrial appliances.

The surface treatment is carried out by forming a layer containing a fluorine-containing polymer on a substrate. If the fluorine-containing polymer to be used is a melt-processible material such as PFA, it is easy to obtain a thick layer by a general industrial production method, Various characteristics of the fluorine-containing polymer can be easily exhibited.

However, the fluorine-containing polymer is poor in adhesiveness to a substrate due to its non-tackiness. There has been proposed a laminate having a primer layer and a fluorine-containing polymer layer obtained by coating a substrate with a primer in which a binder resin such as a heat-resistant resin and a fluorine-containing polymer are blended as a primer for the purpose of improving adhesion, .

For example, a laminate of a three-layer structure (except for the base material) formed on a metal base of a rice cooker, a fluororesin primer layer, a layer formed of a powder coating material containing PFA, and an aqueous dispersion coating material containing PTFE (See, for example, Patent Document 1). Patent Document 1 describes that the rice cooker having such a laminate is excellent in releasability and initial releasability at the time of long-term use.

Japanese Patent Application Laid-Open No. 11-342072

When producing a laminate having a primer layer and a layer containing a fluorine-containing polymer, it is often practiced to coat the fluorine-containing polymer with a melt-processable fluorine-containing polymer in order to form a thick film of the coating film for the purpose of improving abrasion resistance and strength . According to the electrostatic powder coating, a film thickness of about 40 mu m can be obtained after firing in one painting.

However, in the case of electrostatic powder coating, coating film defects (pinholes) may be generated due to electrostatic repulsion between the melt-processable fluorine-containing polymer particles and the coating film defects remain in the coating film even after firing.

On the other hand, the laminate disclosed in Patent Document 1 has a surface layer formed by applying an aqueous dispersion paint on an intermediate layer formed of a PFA powder coating material. This surface layer is excellent in releasability because it is a PTFE coating film. However, the PTFE constituting the surface layer and the PFA constituting the intermediate layer are remarkably different in the thermal expansion coefficient and the melt viscosity, so that the PTFE coating film tends to cause cracks and film defects, .

As described above, there is a room for improvement in the corrosion resistance of the conventional technology.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fluorine-containing laminated body free of coating film defects and excellent in corrosion resistance in view of the above situation, and a method for producing the same.

The present inventors have found that, in a layered product in which a layer containing a melt-processable fluorine-containing polymer is formed on a primer layer, the layer containing the melt-processable fluorine-containing polymer is characterized in that (1) a specific average particle diameter , And (2) a layer formed of a liquid coating material containing particles having another specific average particle diameter including a melt-processable fluorine-containing polymer, the corrosion resistance of the laminate is remarkably improved I found out. This is presumably because coating defects occurring in the coating film formed of the powder coating material are complemented by application of the liquid coating material. The inventor of the present invention has also found that the laminate having such a structure is very useful as a covering material in a cooking apparatus, a kitchen appliance, and the like, and has reached the present invention.

That is, the present invention relates to a process for producing a fluorine-containing fluorine-containing polymer (A), a layer (B) formed of a powder coating (ii) containing a primer layer (A), a melt- Wherein the powder coating material (ii) has an average particle diameter of 5 to 30 占 퐉 and the melt-processible fluorine-containing polymer (c) is a layer containing a fluorine-containing polymer (c) Wherein the average particle diameter of the particles is 0.01 to 1.0 占 퐉.

The present invention also relates to a process for producing a primer coating film (A), which comprises a step (1) of forming a primer coating film (Ap) by applying a primer coating composition (i) (Ii) a step (2) of forming a coating film (Bp) by applying a powder coating material (ii) having a melt processable fluoropolymer (c) on the coating film (Bp) (3) of forming a coating film (Cl) by applying a primer coating film (Ap), a coating film (Bp) and a coating film (Cl) (4) of forming a fluorine-containing laminate including a primer layer (A), a layer (B) and a layer (C), wherein the powder coating (ii) has an average particle diameter of 5 to 30 μm , And the average particle diameter of the particles containing the melt-processible fluorine-containing polymer (c) 0.01 is also a method of producing a fluoro-laminate, characterized in that 1.0㎛.

Hereinafter, the present invention will be described in detail.

The layer (B) constituting the fluorine-containing laminate of the present invention is formed of the powder coating (ii) having an average particle diameter of 5 to 30 μm including the melt-processible fluoropolymer (b).

The melt-processible fluorine-containing polymer (b) has a melt processability in a polymer having a fluorine atom directly bonded to a carbon atom constituting the main chain or side chain. The average particle diameter of the powder coating material (ii) containing the fluorine-containing polymer (b) is 5 to 30 占 퐉. Since the coating material for forming the layer (B) is a powder having a specific average particle diameter, it is easy to obtain a thick coating film with a small number of coatings. As a result, more excellent corrosion resistance is exhibited in the resulting fluorine-containing laminate.

If the average particle diameter of the powder coating material (ii) is too small, the charge amount of the powder becomes large, and pinholes due to the electrostatic repulsion may easily occur. If too large, voids may easily occur in the coating film.

The average particle diameter of the powder coating (ii) is preferably 10 to 25 占 퐉, more preferably 15 to 25 占 퐉. The average particle diameter of the powder coating material (ii) was measured with a laser diffraction particle size distribution measuring apparatus (manufactured by Nippon Denshi Co., Ltd.) and the particle size distribution was measured at a pressure of 0.1 MPa and a measuring time of 3 seconds without using a cascade. And the value corresponding to 50% of the distribution integration.

The layer (C) constituting the fluorine-containing laminate of the present invention is formed of a liquid coating (iii) containing particles having an average particle diameter of 0.01 to 1.0 탆 including the melt-processible fluoropolymer (c). In this specification, the term " liquid phase " refers to a state having fluidity at room temperature of about 20 캜.

The melt-processible fluorine-containing polymer (c) has a melt processability in a polymer having a fluorine atom directly bonded to a carbon atom constituting the main chain or side chain. The average particle diameter of the particles containing the melt-processible fluorine-containing polymer (c) constituting the liquid coating material (iii) is 0.01 to 1.0 탆. Since the particles having such a small particle diameter including the melt-processible fluorine-containing polymer (c) fill up coating film defects of the coating film formed of the powder coating material (ii) having an average particle diameter of 5 to 30 占 퐉, A laminate is obtained.

If the average particle diameter of the particles containing the melt-processible fluorine-containing polymer (c) is too small, the particles tend to agglomerate easily, which may impair the mechanical stability of the liquid coating material. It is difficult to penetrate into a defective portion of the coating film.

The average particle diameter of the particles is preferably 0.1 to 0.7 mu m, more preferably 0.1 to 0.5 mu m. The average particle diameter of the particles containing the melt-processible fluorine-containing polymer (c) can be measured by a transmission electron microscope observation.

The liquid coating material (iii) is not particularly limited as long as it contains particles having an average particle diameter of 0.01 to 1.0 탆 including the melt-processible fluoropolymer (c) and is in a liquid phase. Usually, the melt-processible fluoropolymer (c ) And a liquid medium. More specifically, the liquid coating material (iii) is usually prepared by dispersing the particles containing the melt-processible fluorine-containing polymer (c) in a liquid medium.

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

The substrate constituting the fluorine-containing laminate of the present invention is not particularly limited, and examples thereof include metals such as metals such as iron, aluminum and copper and alloys thereof; Non-metallic inorganic materials such as ceramics, glass, and ceramics. Examples of the alloy flow include stainless steel and the like. As the base material, a metal is preferable, and aluminum or stainless steel is more preferable.

The substrate may be subjected to surface treatment such as degreasing treatment, roughening treatment or the like as necessary. The roughening treatment method is not particularly limited, and examples thereof include chemical etching with an acid or an alkali, anodic oxidation (anodic treatment), sand blast, and the like. The surface treatment can be carried out by uniformly applying the primer coating composition (i) for forming the primer layer (A) without causing cratering, and by improving the adhesion between the base material and the primer coating film (Ap) And the like, depending on the kind of the substrate or the coating composition (i) for a primer. However, it is preferable to use, for example, a sandblast.

The primer layer (A) constituting the fluorine-containing laminate of the present invention is not limited as long as the primer layer (A) is excellent in adhesion to a substrate, but preferably includes the fluorine-containing polymer (a) and the heat resistant resin.

The fluorine-containing polymer (a) is a polymer having a fluorine atom directly bonded to a carbon atom constituting the main chain or side chain. The fluorine-containing polymer (a) may be either melt processible or melt processible.

The fluorine-containing polymer (a) is preferably one obtained by polymerizing the fluorine-containing monoethylenically unsaturated hydrocarbon (I).

The term "fluorine-containing monoethylenically unsaturated hydrocarbon (I)" (hereinafter also referred to as "unsaturated hydrocarbon (I)") refers to an unsaturated hydrocarbon having one vinyl group in which a part or all of hydrogen atoms are substituted by a fluorine atom Hydrocarbons.

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

The unsaturated hydrocarbon (I) is not particularly limited and includes, for example, tetrafluoroethylene [TFE], hexafluoropropylene [HFP], chlorotrifluoroethylene [CTFE], vinylidene fluoride [VdF] [VF]. These may be used alone or in combination of two or more.

The fluorine-containing polymer (a) may be a homopolymer of the unsaturated hydrocarbon (I). Examples of the homopolymer of the unsaturated hydrocarbon (I) include a tetrafluoroethylene homopolymer [TFE homopolymer], polychlorotrifluoroethylene [PCTFE], polyvinylidene fluoride [PVdF], polyvinyl fluoride [PVF] And the like.

The fluorine-containing polymer (a) may be a copolymer of at least one unsaturated hydrocarbon (I) and an unsaturated compound (II) capable of copolymerizing with the unsaturated hydrocarbon (I).

In the present invention, the polymer obtained by polymerizing only one or more of the unsaturated hydrocarbons (I) can be used as the fluorine-containing polymer (a), whereas only one or two or more unsaturated compounds (II) Can not be used as the fluorine-containing polymer (a). In this respect, the unsaturated compound (II) is different from the unsaturated hydrocarbon (I).

The unsaturated compound (II) is not particularly limited and includes, for example, trifluoroethylene [3FH]; And monoethylenically unsaturated hydrocarbons such as ethylene [Et] and propylene [Pr]. These may be used alone or in combination of two or more.

The fluorine-containing polymer (a) may also be a copolymer of two or more of the unsaturated hydrocarbons (I). The copolymer of the at least two unsaturated hydrocarbons (I) and the copolymer of the at least one unsaturated hydrocarbon (I) and the unsaturated compound (II) is not particularly limited, and examples thereof include a binary copolymer, Copolymers and the like.

The binary copolymer is not particularly limited, and examples thereof include VdF / HFP copolymer, Et / CTFE copolymer [ECTFE], Et / HFP copolymer, and the like.

The terpolymer may also be a copolymer of a TFE / HFP copolymer [FEP], a TFE / CTFE copolymer, a TFE / VdF copolymer, a TFE / 3FH copolymer, an Et / TFE copolymer [ETFE] TFE-based copolymer. In the present specification, the "TFE-based copolymer" means a copolymer obtained by copolymerizing TFE with one or more kinds of other monomers other than TFE. The TFE-based copolymer preferably has a proportion of other monomers other than TFE added to the TFE-based copolymer in excess of 1% by mass of the total mass of the TFE and the other monomers.

Examples of the terpolymer include VdF / TFE / HFP copolymer and the like.

The other monomer other than the TFE in the TFE-based copolymer may be another monomer (III) copolymerizable with the following TFE. The other monomer (III)

_{X (CF 2) m O n} CF = CF 2

(In the formula, X represents -H, -Cl or -F, m represents an integer of 1 to 6, and n represents an integer of 0 or 1), except for HFP, Wherein R &

C ₃ F ₇ O [CF (CF ₃ ) CF ₂ O] _p -CF = CF ₂

(Wherein p represents an integer of 1 or 2), or a compound represented by the following formula

_{X (CF 2) q CY =} CH 2

(In the formula, X is as defined above, Y represents -H or -F, and q represents an integer of from 1 to 6), more preferably at least one kind of monomer selected from the group consisting of . These may be used alone or in combination of two or more. Examples of such TFE-based copolymers include TFE / perfluoro (alkyl vinyl ether) [PAVE] copolymer [PFA].

The fluorine-containing polymer (a) may also be modified polytetrafluoroethylene [modified PTFE]. In the present specification, the term " modified PTFE " means that a copolymer is copolymerized with a small amount of a comonomer to such an extent as not to impart melt processability to the resulting copolymer. The small amount of the comonomer is not particularly limited and includes, for example, HFP and CTFE among the unsaturated hydrocarbons (I), 3FH among the unsaturated compounds (II), and the other monomers (III ) Among PAVE, perfluoro (alkoxyalkyl vinyl ether), (perfluoroalkyl) ethylene and the like. These small amounts of comonomers may be used alone or in combination of two or more.

The proportion of the small amount of the comonomer added to the modified PTFE differs depending on the type thereof. When PAVE, perfluoro (alkoxyalkyl vinyl ether) or the like is used, the ratio of the TFE to the small amount of the comonomer By mass to 1% by mass of the total mass of the resin composition.

The fluorine-containing polymer (a) may be one kind or two or more kinds, or a mixture of one kind of the homopolymer of the unsaturated hydrocarbon (I) and one or more kinds of the copolymer of the unsaturated hydrocarbon (I) Or a mixture of two or more kinds of the copolymer of the unsaturated hydrocarbon (I).

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

The fluorine-containing polymer (a) may also be obtained by polymerizing a perfluoroalkyl group-containing ethylenically unsaturated monomer (IV) having a perfluoroalkyl group (hereinafter also referred to as "unsaturated monomer (IV)"). The unsaturated monomer (IV)

(Wherein 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, 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).

The fluorine-containing polymer (a) may be a homopolymer of the unsaturated monomer (IV) or a copolymer of the unsaturated monomer (IV) and the monomer (V) capable of copolymerizing with the unsaturated monomer (IV) .

Examples of the monomer (V) include, but are not limited to, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, polyethylene glycol di (meth) acrylate, N- methylolpropane acrylamide, (Meth) acrylic acid derivatives such as alkyl esters of (meth) acrylic acid having 1 to 20 carbon atoms in the alkyl group; Substituted or unsubstituted ethylene such as ethylene, vinyl chloride, vinyl fluoride, styrene,? -Methylstyrene and p-methylstyrene; Vinyl ethers such as alkyl vinyl ethers having 1 to 20 carbon atoms in the alkyl group and alkyl vinyl vinyl ethers having 1 to 20 carbon atoms in the alkyl group; Vinyl ketones such as vinyl alkyl ketone in which the alkyl group has 1 to 20 carbon atoms; Aliphatic unsaturated polycarboxylic acids such as maleic anhydride and derivatives thereof; And polyenes such as butadiene, isoprene and chloroprene.

The fluorine-containing polymer (a) can be obtained by a conventionally known polymerization method such as emulsion polymerization or the like.

As the fluorine-containing polymer (a), at least one polymer selected from the group consisting of a TFE homopolymer, a modified PTFE and the TFE-based copolymer is preferable because the obtained fluorine-containing laminate is excellent in corrosion resistance and water vapor resistance. As the TFE-based copolymer, at least one kind of copolymer selected from the group consisting of FEP and PFA is preferable.

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

As the fluorine-containing polymer (a), it is preferable to include a TFE-based copolymer in view of the excellent adhesion between the primer layer (A) and the layer (B) in the obtained fluorine-containing laminate. The fluorine-containing laminate having excellent adhesion between the primer layer (A) and the layer (B) has excellent resistance to water vapor, so that occurrence of coating film defects such as blisters can be suppressed even in the presence of water vapor. Examples of the fluorine-containing polymer (a) containing a TFE-based copolymer include PFA alone, a mixture of TFE homopolymer and FEP, a mixture of TFE homopolymer and PFA, a mixture of modified PTFE and FEP, or a mixture of modified PTFE and PFA . The fluorine-containing polymer (a) in the primer layer (A) is preferably a fluorine-containing polymer having excellent corrosion resistance and water vapor resistance and excellent adhesion between the primer layer (A) and the layer (B) , A mixture of TFE homopolymer and PFA, or a mixture of TFE homopolymer and FEP, more preferably a mixture of TFE homopolymer and FEP.

The heat-resistant resin that can form the primer layer (A) may be any resin that is generally recognized to have heat resistance, and is preferably a resin having a continuous usable temperature of 150 ° C or higher. However, the above-mentioned fluorine-containing polymer (a) is excluded as the heat resistant resin.

The heat-resistant resin is not particularly limited, and examples of the heat-resistant resin include a group consisting of a polyamideimide resin, a polyimide resin, a polyether sulfone resin, a polyether imide resin, a polyether ether ketone resin, an aromatic polyester resin and a polyarylene sulfide resin Is preferably at least one kind of resin selected from the group consisting of

The polyamideimide resin [PAI] is a resin containing a polymer having an amide bond and an imide bond in a molecular structure. The PAI is not particularly limited and includes, for example, a reaction of an aromatic tetravalent carboxylic acid such as pyromellitic acid with an aromatic diamine having an amide bond in the molecule; The reaction of an aromatic trivalent carboxylic acid such as trimellitic anhydride with a diisocyanate such as a diamine such as 4,4-diaminophenyl ether or diphenylmethane diisocyanate; A resin containing a high molecular weight polymer obtained by various reactions such as a reaction between a dibasic acid having an aromatic imide ring in its molecule and a diamine, and the like. As the PAI, it is preferable to include a polymer having an aromatic ring in the main chain from the viewpoint of excellent heat resistance.

The polyimide resin [PI] is a resin containing a polymer having an imide bond in a molecular structure. The PI is not particularly limited, and for example, a resin containing a high molecular weight polymer obtained by, for example, reaction of an aromatic tetravalent carboxylic acid anhydride such as pyromellitic anhydride. As the PI, it is preferable to include a polymer having an aromatic ring in the main chain from the viewpoint of excellent heat resistance.

The polyethersulfone resin [PES]

Is a resin comprising a polymer having a repeating unit represented by the following formula: The PES is not particularly limited, and examples thereof include resins containing a polymer obtained by polycondensation of dichlorodiphenyl sulfone and bisphenol.

The heat-resistant resin is excellent in adhesion to a substrate and has sufficient heat resistance even under the temperature at the time of firing which is carried out when the fluorine-containing laminate is formed. From the viewpoint of excellent corrosion resistance and water vapor resistance, the obtained fluorine- And PES are preferable. PAI, PI and PES may each contain one or more species.

It is more preferable that the heat resistant resin is at least one resin selected from the group consisting of PAI and PI from the viewpoint of excellent adhesiveness to a substrate and heat resistance.

As the heat-resistant resin, it is preferable to include at least one resin selected from the group consisting of PES and 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 and PAI and PI. It is particularly preferable that the heat resistant resin is a mixture of PES and PAI.

When the heat resistant resin comprises at least one resin selected from the group consisting of PES and PAI and PI, the PES is preferably 65 to 85% by mass of the total amount of the PES and PAI and / or PI desirable. And more preferably 70 to 80 mass%.

The content of the heat resistant resin is preferably 10 to 50 mass% of the sum of the solid content of the heat resistant resin and the fluoropolymer (a). More preferably from 15 to 40% by mass, and still more preferably from 15 to 30% by mass.

The primer layer (A) is usually formed on a substrate. The primer layer (A) is obtained, for example, by applying a coating composition (i) for a primer, which contains a fluorine-containing polymer (a) and a heat-resistant resin, on a substrate, . Since the fluorine-containing polymer (a) and the heat-resistant resin differ in surface tension from each other in the primer layer (A) thus obtained, the fluorine-containing polymer (a) The above-mentioned fluorine-containing polymer (a) is mainly disposed on the surface side of the substrate, and the heat-resistant resin is mainly disposed on the substrate side.

When the primer layer (A) contains the fluorine-containing polymer (a) and the heat-resistant resin, the heat-resistant resin has excellent adhesiveness to the substrate and therefore has excellent adhesion to the substrate. The primer layer (A) is also excellent in adhesion with the layer (B) because the fluorine-containing polymer (a) has affinity with the melt-processible fluorine-containing polymer (b). Thus, when the fluorine-containing polymer (a) is composed of the heat-resistant resin, the primer layer (A) has excellent adhesion to both the base material and the layer (B).

It is preferable that the primer layer (A) comprises a polymer component and an additive which will be described later. It is preferable that the polymer component of the primer layer (A) is a fluorine-containing polymer (a) and a heat-resistant resin. In the present specification, "the polymer component of the primer layer (A) is the fluorine-containing polymer (a) and the heat-resistant resin" means that the polymer in the primer layer (A) is only the fluorine- it means. The primer layer (A) has excellent adhesion to both the base material and the layer (B) described later, because the polymer component is a fluorine-containing polymer (a) and a heat-resistant resin.

It is preferable that the polymer component is a fluorine-containing polymer (a) and a heat-resistant resin from the viewpoint that the primer layer (A) efficiently exerts excellent adhesion to both the base material and the layer (B) Containing polymer (a) and the heat-resistant resin from the viewpoint that the fluorine-containing polymer (a) and the water vapor resistance can be further improved. Other resins can be mentioned later.

The primer layer (A) preferably has a film thickness of 5 to 30 mu m. If the film thickness is too thin, pinholes are likely to be generated, and the corrosion resistance of the fluorine-containing laminate may be deteriorated. If the film thickness is too large, cracks are likely to occur, and the water vapor resistance of the fluorine-containing laminate may be lowered. A more preferable upper limit of the film thickness of the primer layer (A) is 20 mu m.

As the melt-processible fluorine-containing polymer (b) constituting the powder coating material (ii), those having melt processability among the above-mentioned fluorine-containing polymer (a) can be used. The melt-processible fluorine-containing polymer (b) is preferably a fluorine-containing polymer having an excellent adhesion between the primer layer (A) and the layer (C) and a fluorine- And a melt viscosity of 10 ⁶ (Pascal second) or less at a temperature higher than the melting point by 50 캜 and is preferably the TFE-based copolymer described above. The melt-processible fluorine-containing polymer (b) may be one kind or two or more kinds. It is more preferable that the melt processible fluorine-containing polymer (b) is at least one fluoropolymer selected from the group consisting of PFA and FEP. The melt-processible fluorine-containing polymer (b) may be a single PFA or FEP, or a mixture thereof. From the viewpoint of excellent heat resistance, the melt processible fluorine-containing polymer (b) is more preferably PFA. The melting point can be obtained as a temperature corresponding to the maximum value in the heat of fusion curve when the temperature is raised at a rate of 10 ° C / minute by using a differential scanning calorimetry (DSC) apparatus.

Using the flow tester CFT-500C (manufactured by Shimadzu Seisakusho), the above melt viscosity was extruded through an orifice having a diameter of 2.1 mm and a length of 8 mm under a load of 7 kgf at a temperature higher by 50 캜 than the melting point. Respectively.

The powder coating (ii) may contain a small amount of PTFE (TFE homopolymer and / or modified PTFE) together with the melt-processible fluorine-containing polymer (b) for the purpose of refining spherical crystals. In this case, the content of PTFE is preferably 0.01 to 10.0 mass% with respect to the melt-processible fluorine-containing polymer (b).

The layer (B) is preferably laminated on the primer layer (A). It is preferable that a layer (C) described later is laminated on the layer (B).

The powder coating (ii) is preferably such that the polymer component is a melt-processible fluorine-containing polymer (b). Means that the polymer in the powder coating (ii) is only the melt-processible fluoropolymer (b). The term "powder coating (ii)" means that the polymer component is the melt-processible fluoropolymer (b). The obtained layer (B) is obtained by mixing the above-mentioned primer layer ((B)) with the polymerizable component (B) of the powder coating material (ii) A) and the layer (C) described later.

The layer (B) preferably has a thickness of 10 to 90 mu m. If the film thickness is too thin, the corrosion resistance of the obtained fluorine-containing laminate may not be sufficient. If the film thickness is too large, water permeated from the layer (B) is difficult to escape, and the water vapor resistance of the fluorine-containing laminate may be deteriorated. A more preferable lower limit of the film thickness of the layer (B) is 20 mu m, and a more preferable upper limit is 80 mu m.

As the melt-processible fluorine-containing polymer (c) constituting the liquid coating material (iii), the fluorine-containing polymer (a) having melt processability can be used.

The melt-processible fluorine-containing polymer (c) is common to the melt-processible fluorine-containing polymer (b) in that it has melt processability among the above-mentioned fluorine-containing polymer (a) Is different from the above-mentioned melt-processible fluorine-containing polymer (b) in the powder coating (ii) in that it is a liquid coating material (iii) containing particles containing a processable fluorine-containing polymer (c).

The melt-processible fluorine-containing polymer (c) is advantageous in that it has excellent film-forming properties, that the layer (C) obtained is excellent in adhesion to the layer (B), and that the obtained fluorine-containing laminate has excellent corrosion resistance and water vapor resistance , And the same kind as that of the melt-processible fluorine-containing polymer (b). It is also preferable that the polyester resin has a melting point of 150 to 350 ° C and a melt viscosity of 10 ⁶ (Pascal-second) or less at a temperature higher than the melting point by 50 ° C. Examples of such a melt-processible fluorine-containing polymer (c) include a TFE-based copolymer. As the melt-processible fluorine-containing polymer (c), at least one polymer selected from the group consisting of PFA and FEP is preferable from the viewpoint of excellent heat resistance, non-tackiness and film formability. The melt-processible fluorine-containing polymer (c) may be PFA alone, FEP alone, or a mixture of PFA and FEP. As the melt-processible fluorine-containing polymer (c), PFA is more preferable because of its superior heat resistance.

As described above, the liquid coating material (iii) is generally formed by dispersing the particles containing the melt-processible fluorine-containing polymer (c) in a liquid medium.

The liquid medium usually comprises water and / or an organic liquid. In the present specification, the term " organic liquid " means an organic compound and means liquid at room temperature of about 20 캜.

When the liquid medium in the liquid coating material (iii) mainly contains an organic liquid, the organic liquid is not particularly limited and includes, for example, N-methyl-2-pyrrolidone, Nitrogen-containing organic liquids such as N, N-dimethylacetamide; Aromatic hydrocarbon solvents such as toluene, xylene, trimethylbenzene, methylethylbenzene, propylbenzene and butylbenzene; A saturated hydrocarbon solvent having 6 to 12 carbon atoms; lactones such as? -butyrolactone; Acyclic esters such as butyl acetate; Ketones such as methyl isobutyl ketone and methyl ethyl ketone; Glycols such as ethylene glycol, triethylene glycol and propylene glycol; Glycol ethers such as butyl cellosolve; And monoalcohols such as 1-butanol and diacetone alcohol.

Commercially available Solvesso 100, Solvesso 150, Solvesso 200 (all trade names, manufactured by Exxon Mobil Corporation) may be used as the aromatic hydrocarbon solvent. As the saturated hydrocarbon solvent, a commercially available mineral spirit (Japanese Industrial Standard, Industrial Gasoline No. 4) or the like may be used.

The organic liquid may be used alone, or two or more kinds may be used in combination.

In terms of environmental problems, it is preferable that the liquid medium mainly contains water.

When the liquid medium mainly contains water, the liquid coating material (iii) usually comprises a surfactant for the purpose of dispersing and stabilizing particles containing the fluorine-containing polymer (c).

The surfactant is not particularly limited, and examples thereof include nonionic surfactants such as fluorine-containing nonionic surfactants; Anionic surfactants such as fluorine-containing anionic surfactants; And cationic surfactants such as fluorine-containing cationic surfactants. In the liquid coating material (iii), the organic liquid may be used together with the surfactant for the purpose of dispersing and stabilizing particles containing the fluorine-containing polymer (c).

The viscosity of the liquid coating material (iii) is preferably 0.1 to 50,000 mPa · s. If the viscosity is too low, it tends to cause the layer to flow down at the time of coating, which may make it difficult to obtain a desired film thickness. When the viscosity is too high, the coating workability may deteriorate. The surface smoothness and the like may be lowered. A more preferred lower limit is 1 mPa · s, and a more preferable upper limit is 30000 mPa · s.

The viscosity can be measured by a B-type viscometer TVB-10 (manufactured by Toki Sangyo K.K.).

The liquid coating material (iii) may contain a filler for the purpose of imparting properties, improving physical properties, and increasing the properties of the obtained fluorine-containing laminate. Examples of the properties and physical properties include strength, durability, weather resistance, flame retardancy, and designability. When a fluorine-containing filler is used, the fluorine-containing laminate of the present invention has good luminous feeling.

The filler is not particularly limited and includes, for example, wood powder, quartz, carbon black, clay, talc, diamond, corundum, silica, boron nitride, boron carbide, silicon carbide, fused alumina, tourmaline, jade, germanium, Flake flat pigments, scaly flake pigments, glass, various reinforcements, various extenders, conductive fillers, and the like. When the fluorine-containing laminate of the present invention is required to have luminosity, the above-mentioned filler is preferably a light-bright filler. The " light-permeable filler " is a filler that can give a brilliance to the resulting fluorine-containing laminate.

Examples of the fillers include those classified as bright white flat pigments and scaly pigments, and glass. One or more of these fillers can be used. There are no particular limitations on those classified into the above-mentioned bright white flat pigments and scaly pigments, and examples thereof include mica powder (including those coated with acid valence titanium) and metal powder. The glass is not particularly limited, and examples thereof include glass beads, glass bubbles, glass flakes and glass fractions such as glass fibers. In addition, a glass powder coated with a metal such as gold, silver or nickel, or a glass powder coated with titanium oxide, iron oxide or the like can be used. One or two or more of the above-mentioned bright white flat pigments and scaly pigments may be used.

As the filler, at least one filler selected from the group consisting of mica powder, metal powder and glass powder is more preferable. Such a filler may be mica powder, metal powder or glass powder, or other filler capable of imparting luminosity to mica powder, metal powder or glass powder and fluorine-containing laminate. The filler may be a mica powder alone, a metal powder alone, a glass powder alone, a mixture of mica powder and metal powder, a mixture of mica powder and glass powder, or a mixture of metal powder and glass powder.

The filler is preferably 0.01 part by mass or more and 5 parts by mass or less based on 100 parts by mass of the fluorine-containing polymer (c).

The metal powder is not particularly limited, and examples thereof include metal powder such as aluminum, iron, tin, zinc, gold, silver and copper; Aluminum alloy, stainless steel, and the like. The shape of the metal powder is not particularly limited and may be, for example, a granular shape or a flake shape, but a flake shape is preferable from the viewpoint of excellent luminosity. For example, as the shape of the aluminum powder, a flake shape is preferable.

It is particularly preferable that the filler is at least one filler selected from the group consisting of mica powder and glass powder from the viewpoint of excellent corrosion resistance of the obtained fluorine-containing laminate. The mica powder and the glass powder are preferably light-bright fillers.

The filler is one of the preferable forms because it is at least one filler selected from the group consisting of mica powder and aluminum powder from the viewpoint of excellent brightness and economical efficiency. It is more preferable that the mica powder and the aluminum powder are light-filled fillers. Such fillers include mica powder alone, aluminum powder alone, or a mixture of mica powder and aluminum powder.

The liquid coating material (iii) may also contain a small amount of PTFE (TFE homopolymer and / or modified PTFE) together with particles containing the melt-processible fluoropolymer (c) for the purpose of refining the glass. In this case, the content of PTFE is preferably 0.01 to 10.0 mass% with respect to the melt-processible fluorine-containing polymer (c).

It is preferable that the liquid coating material (iii) does not contain a coloring pigment. Since the colored pigment is generally considered to cause deterioration of the corrosion resistance, if the liquid coating material (iii) does not contain a coloring pigment, the resulting fluorine-containing laminate has better corrosion resistance.

It is also preferable that the liquid coating material (iii) comprises a polymer component and an additive. The liquid coating material (iii) is preferably a polymer component which is a melt-processible fluorine-containing polymer (c). In the present specification, the "liquid paint (iii) is a polymer (c)" is a polymer in the liquid coating material (iii) means that the polymer (c) is a melt-processible fluoropolymer. The layer (C) to be obtained has excellent adhesion to the layer (B) because the polymer component of the liquid coating material (iii) is the melt-processible fluorine-containing polymer (c).

In the fluorine-containing laminate of the present invention, it is preferable that the layer (C) is formed on the layer (B), and it is preferable that the layer (C) is fired at a temperature not lower than the melting point of the melt-processible fluoropolymer (c).

The layer (C) preferably has a film thickness of 1 to 30 mu m. If the film thickness is too thin, coating film defects of the layer (B) can not be sufficiently filled, and the corrosion resistance of the fluorine-containing laminate may be deteriorated. If the film thickness is too large, cracks tend to occur in the layer (C), and corrosion resistance may be deteriorated. A more preferable lower limit of the film thickness of the layer (C) is 5 mu m, and a more preferable upper limit is 20 mu m.

It is to be noted that the primer layer (A) has a thickness of 5 to 30 탆, the layer (B) has a thickness of 10 to 90 탆 and the layer (C) has a thickness of 1 to 30 탆 Which is one of the preferred embodiments of the present invention.

The order of lamination of the respective layers constituting the fluorine-containing laminate of the present invention is not particularly limited, but it is preferable that the substrate, the primer layer (A), the layer (B) and the layer (C) Do. As a result, the effect of improving the corrosion resistance by the layer (B) and the layer (C) can be more remarkably exhibited.

It is particularly preferable that the substrate, the primer layer (A), the layer (B), and the layer (C) are laminated in this order and the layer (C) is laminated adjacent to the layer Do.

Usually, the fluorine-containing laminate of the present invention does not include another layer between the respective layers of the substrate, the primer layer (A), the layer (B), and the layer (C) ) And the layer (B), or between the layer (B) and the layer (C).

The fluorine-containing laminate of the present invention may be any of those having the primer layer (A), the layer (B), and the layer (C) as described above and a layer is further formed on the layer , It is preferable that the layer (C) is the outermost layer. By arranging the layer (C) on the outermost layer, the corrosion resistance of the fluorine-containing laminate can be improved more effectively.

The fluorine-containing laminate of the present invention is a fluorine-containing laminate of the present invention, in which the primer layer (A), the layer (B), and the layer (C) Or the upper surface of the layer (B) may be printed with characters, drawings, and the like.

The present invention is also a method for producing a fluorine-containing laminate. According to the production method described below, a fluorine-containing laminate having no coating film defect as described above and excellent in corrosion resistance can be easily produced.

The method for producing a fluorine-containing laminate of the present invention includes a step (1) of forming a primer coating film (Ap) by applying a primer coating composition (i) on a base material.

In the step (1), it is preferable that the coating composition (i) for a primer contains a fluorine-containing polymer (a) and a heat-resistant resin. The fluorine-containing polymer (a) and the heat-resistant resin are as described above for the primer layer (A). The coating composition (i) for a primer may be a liquid or a powder. When the coating composition (i) for a primer is a liquid, it contains a liquid medium together with the fluorine-containing polymer (a) and the heat-resistant resin. The liquid medium usually comprises water and / or an organic liquid. In the present specification, the term " organic liquid " means an organic compound and means liquid at room temperature of about 20 캜.

When the liquid medium of the coating composition (i) for primer mainly comprises an organic liquid, the heat-resistant resin and the fluorine-containing polymer (a) are dispersed as particles in the liquid medium, and / It is dissolved. The organic liquid is not particularly limited and includes, for example, a nitrogen-containing organic liquid such as N-methyl-2-pyrrolidone, 2-pyrrolidone, and N, N-dimethylacetamide; Aromatic hydrocarbon solvents such as toluene, xylene, trimethylbenzene, methylethylbenzene, propylbenzene and butylbenzene; A saturated hydrocarbon solvent having 6 to 12 carbon atoms; lactones such as? -butyrolactone; Acyclic esters such as butyl acetate; Ketones such as methyl isobutyl ketone and methyl ethyl ketone; Glycols such as ethylene glycol, triethylene glycol and propylene glycol; Glycol ethers such as butyl cellosolve; And monoalcohols such as 1-butanol and diacetone alcohol.

Commercially available Solvesso 100, Solvesso 150, Solvesso 200 (both trade names, manufactured by Exxon Mobil Corporation) may be used as the aromatic hydrocarbon solvent. As the saturated hydrocarbon solvent, a commercially available mineral spirits (Japanese Industrial Standard, Industrial Gasoline No. 4) may be used.

The organic liquid may be used alone, or two or more kinds may be used in combination.

When the liquid medium of the coating composition for a primer (i) mainly comprises water, the heat-resistant resin is dispersed as particles in the liquid medium or dissolved in the liquid medium, and the fluorine-containing polymer (a) And dispersed in the liquid medium as particles.

The coating composition (i) for a primer is prepared by adding a surfactant for the purpose of dispersing and stabilizing particles containing the fluorine-containing polymer (a) when the liquid medium mainly contains water. The surfactant is not particularly limited, and examples thereof include nonionic surfactants such as fluorine-containing nonionic surfactants; Anionic surfactants such as fluorine-containing anionic surfactants; And cationic surfactants such as fluorine-containing cationic surfactants. The coating composition (i) for a primer may be used in combination with the above-mentioned surfactant for the purpose of dispersing and stabilizing particles containing the fluorine-containing polymer (a).

The coating composition (i) for a primer described above is also a method described in Japanese Patent Publication No. 49-17017, that is, a method in which the dispersoid is a particle comprising particles and a heat-resistant resin containing the fluorine-containing polymer (a) (A) and a heat-resistant resin are added to the organic solvent in which the organic solvent and the whole layer agent are added to the aqueous dispersion, wherein the organic solvent and the heat- Or an organosol obtained by a method such as a top coating method.

The coating composition (i) for a primer is preferably a liquid one because of its excellent adhesion with a base material, and from the viewpoint of environmental problems, it is more preferable that the liquid medium mainly contains water.

When the coating composition (i) for a primer is a liquid, the viscosity of the coating composition (i) for the primer is preferably 0.1 to 50,000 mPa · s. If the viscosity is too low, it tends to flow down during application onto the substrate, and it may be difficult to obtain a desired film thickness. On the other hand, if the viscosity is too high, the coating workability may deteriorate, The film thickness of the primer coating film Ap may not become uniform, and the surface smoothness or the like may be lowered. A more preferred lower limit is 1 mPa · s, and a more preferable upper limit is 30000 mPa · s.

The viscosity can be measured by a B-type viscometer TVB-10 (manufactured by Toki Sangyo K.K.).

In the coating composition (i) for a primer, the fluorine-containing polymer (a) preferably has an average particle diameter of 0.01 to 5 mu m. When the heat-resistant resin is dispersed as particles in the coating composition (i) for the primer, the average particle diameter of the heat-resistant resin is preferably 0.2 to 8 mu m.

In the coating composition for a primer (i), the heat-resistant resin includes at least one resin selected from the group consisting of a polyethersulfone resin (PES), a polyamideimide resin (PAI) and a polyimide resin (PI) , And the polyethersulfone resin is preferably 65 to 90 mass% of the total amount of the polyether sulfone resin and at least one resin selected from the group consisting of the polyamideimide resin and the polyimide resin. If the polyether sulfone resin is too small, there is a fear that the water vapor resistance of the obtained fluorine-containing laminate is lowered, and if the polyether sulfone resin is too much, corrosion resistance may be lowered. A more preferred upper limit is 85 mass%. The ratio of the PES is substantially the same in the primer layer (A) since the above-mentioned heat resistant resin does not decompose even in the firing which is performed when forming the fluorine-containing laminate. The "total amount of PES and PAI and PI" is the total amount of PES and either of PAI and PI contained in the coating composition (i) for primer when only one of PAI and PI is included.

In the coating composition for a primer (i), it is preferable that the heat-resistant resin is 10 to 50% by mass of the total amount of solids of the heat-resistant resin and the fluorine-containing polymer (a). In the present specification, the term "solid content" means a solid at 20 ° C. Refers to the total amount of the solid content of the heat resistant resin and the fluorine-containing polymer (a), which is obtained by applying the coating composition (i) for primer onto the substrate, drying at a temperature of 80 to 100 캜, Means the total mass of the heat-resistant resin and the fluorine-containing polymer (a) in the residue after calcination for 45 minutes.

If the amount of the heat resistant resin is too small, the adhesion between the primer layer (A) and the base material in the resulting fluorine-containing laminate may not be sufficient. When the amount of the heat resistant resin is too large, the adhesion between the primer layer (A) and the layer (B) in the resulting fluorine-containing laminate may not be sufficient. A more preferred lower limit is 15% by mass, and a more preferable upper limit is 40% by mass.

The coating composition (i) for a primer preferably further comprises an additive for the purpose of further improving paint workability and corrosion resistance and water vapor resistance of the obtained fluorine-containing laminate together with the fluorine-containing polymer (a) and the heat- It may be.

The additive is not particularly limited and includes, for example, a leveling agent, a solid lubricant, an anti-settling agent, a water absorbent, a surface conditioner, a thixotropic property imparting agent, a viscosity adjusting agent, an antigelling agent, an ultraviolet absorber, a light stabilizer, An antifogging agent, an antioxidant, an antistatic agent, a silane coupling agent, a wood flour, a quartz, a carbon black, a clay, a talc, a diamond, a tourmaline, a jade, a germanium, an extender pigment, an aluminum flake Metal powders such as bright white flat pigments, scaly pigments, glass, various reinforcing materials, various kinds of increasing materials, conductive fillers, gold, silver and copper.

The coating composition (i) for a primer is preferably a fluorine-containing polymer (a) and a heat-resistant resin because the obtained primer layer (A) efficiently exerts excellent adhesion to both the base material and the layer However, from the viewpoint of further improving the corrosion resistance and the water vapor resistance of the fluorine-containing laminate, the fluorine-containing polymer (a) and the heat resistant resin may further contain other resins.

The other resin is not particularly limited and examples thereof include phenol resin, urea resin, epoxy resin, urethane resin, melamine resin, polyester resin, polyether resin, acrylic resin, acrylic silicone resin, silicone resin, silicone polyester resin And the like. It is preferable that the other resins have heat resistance because they are obtained by firing the fluorine-containing laminate of the present invention.

The above step (1) is a step of forming a primer coating film (Ap) by applying a coating composition (i) for a primer onto a substrate.

When the coating composition (i) for a primer is in the form of a liquid, it may be applied by spray coating, roll coating, doctor blade coating, dip coating, impregnation coating, spin flow coating, , Curtain flow coating and the like, among which spray painting is preferable. When the coating composition (i) for a primer is a powder, electrostatic coating, flow-dipping, rotolining and the like can be mentioned. Among them, electrostatic coating is preferable.

The step (1) may be a step of forming the primer coating film (Ap) by applying the coating composition (i) for a primer onto the substrate, and firing may be carried out after the application and before the step (2) , And may not be subjected to firing. When the coating composition (i) for a primer is in the form of a liquid, it may be subjected to further drying after the application, or may not be dried.

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

When the coating composition (i) for a primer is in a liquid phase, it is preferable that the step (1) is applied to a substrate and then dried. In addition, it is preferable that in the step (4) to be described later, firing is not performed in order to fuse the coating film laminate.

In the case where the coating composition (i) for a primer is a powder, it is preferable that the step (1) is applied to a substrate and then fired.

The primer coating film Ap is formed by applying the coating composition (i) for a primer onto a substrate. The primer coating film Ap may be formed only by the coating in the step (1), or may be formed by applying and drying after the coating, or may be formed by drying, if necessary, It is possible. The primer coating film Ap becomes the primer layer (A) in the obtained fluorine-containing laminate.

The method for producing a fluorine-containing laminate of the present invention is a step (2) of forming a coating film (Bp) by applying a powder coating (ii) containing a melt-processible fluoropolymer (b) onto a primer coating film (Ap) .

The powder coating (ii) contains the melt-processible fluorine-containing polymer (b) and has an average particle diameter of 5 to 30 占 퐉. Since the powder coating material (ii) is a powder, it is easy to obtain a thick coating film with a small number of coatings.

In the step (2), the coating film (Bp) is formed by coating the powder coating material (ii) on the primer coating film (Ap). The method of application is not particularly limited and, for example, the same method as the coating method in the case where the coating composition (i) for a primer is powder, and electrostatic painting is preferable among them.

The coating film (Bp) is formed by applying the powder coating (II) on the primer coating film (Ap). The coating film (Bp) is a layer (B) in the resulting fluorine-containing laminate.

In the method for producing a fluorine-containing laminate of the present invention, a step of baking the obtained coating film laminate after forming the coating film (Bp) in the above step (2) may be provided. That is, the manufacturing method may include a step (2 ') of baking the coating film laminate including the primer coating film (Ap) and the coating film (Bp). In the step (2 '), the primer coating film Ap may be either not baked or already baked (before the formation of the coating film Bp).

The step (3) of applying the liquid coating material (iii) described later after the above-mentioned step (2 ') is carried out can remove the coating film defects caused by the coating of the powder coating material (ii) The remaining fluorine-containing laminate can be more reliably filled with the liquid coating material (iii) by coating, so that the obtained fluorine-containing laminate is excellent in corrosion resistance with few coating film defects.

The firing in the step (2 ') is preferably carried out at a temperature of 260 to 410 캜 for 10 to 30 minutes as in the case of firing in the step (1).

The production method of the present invention is characterized in that a liquid coating (iii) containing particles having an average particle diameter of 0.01 to 1.0 탆 including the melt-processible fluoropolymer (c) is applied on the coating film (Bp) (3).

Since the particles containing the melt-processible fluorine-containing polymer (c) have a small particle diameter of 0.01 to 1.0 탆 in average particle diameter, they penetrate coating film defects of the coating film (Bp) to fill up coating film defects, The fluorine-containing laminate can be formed.

The method of applying the liquid coating material (iii) on the coating film (Bp) is not particularly limited and, for example, the same method as the coating method in the case where the coating composition (i) for a primer described above is liquid Especially, spray painting is preferable.

The coating film (Cl) may be formed by baking as necessary after the application. The coating film (Cl) becomes the layer (C) in the resulting fluorine-containing laminate.

The production method of the present invention is characterized in that the substrate, the primer layer (A), the layer (B) and the primer layer (B) are fired by firing a coating film laminate including the primer coating film (Ap) And a step (4) of forming a fluorine-containing laminate including the layer (C).

In the step (4), the fluorine-containing laminate finally obtained by the above step may be one comprising the substrate, the primer layer (A), the layer (B) and the layer (C) Not all of the layer (B) and the layer (C) need be formed first in the step (4).

Therefore, it is also possible that all of the primer coating film Ap, the coating film Bp and the coating film Cl provided in the step (4) are not baked in the step preceding the step (4) , And at least one of them may be fired in the process before the step (4).

The firing in the step (4) is preferably carried out at a temperature of 260 to 410 캜 for 10 to 30 minutes in the same manner as the firing in the above-mentioned steps (1) to (3).

In the method for producing a fluorine-containing laminate of the present invention, in order to more reliably fill coating film defects caused by coating of the powder coating material (ii), the coating film (Bp) obtained after the formation of the coating film (Bp) And a step of firing the laminate.

That is, the above manufacturing method comprises a step (1) of forming a primer coating film (Ap) by applying a primer coating composition (i) on a substrate, a step (1) of forming a primer coating film (Ap) A step (2) of forming a coating film (Bp) by applying a powder coating material (ii) comprising a primer coating film (Ap) and a coating film (Bp) (2 ') of forming a fluorine-containing laminate (P) containing a primer layer (A) and a layer (B) (3) of forming a coating film (Cl) by applying a liquid coating material (iii) containing a primer coating film (Ap), a coating film (Bp) and a coating film By firing the laminate, the fluorine containing the substrate, the primer layer (A), the layer (B) and the layer (C) (4), wherein the powdery coating (ii) has an average particle diameter of 5 to 30 占 퐉, and the average particle diameter of the particles containing the melt-processible fluorine-containing polymer (c) 0.01 to 1.0 占 퐉 is one of the preferred embodiments of the present invention.

The method for producing a fluorine-containing laminate of the present invention may further comprise the step of printing characters, drawings, etc. after the step (1) of forming the primer coating film (Ap) or after the step (2) . For example, when the fluorine-containing laminate is used in a rice cooker, the letters, drawings, and the like are letters and lines indicating the amount of water.

The printing method is not particularly limited, and may be, for example, a pad transfer printing. The printing ink used for the printing is not particularly limited, and examples thereof include a composition containing a PES and a TFE homopolymer and titanium oxide.

The fluorine-containing laminate of the present invention may constitute a coated article. Since the fluorine-containing laminate is excellent in corrosion resistance, it can be suitably used in all fields requiring corrosion resistance. The coated article is not particularly limited and may be used for applications using non-adhesive, heat-resistant, slippery, etc. properties of the fluorine-containing polymer. Examples of the coated article include a frying pan, a pressure pot, a pot, a grill pan, Cookers such as ovens, hot plates, bread loafs, kitchen knives, and gas tables; Kitchen utensils such as electric pots, ice-making trays, molds, and range hoods; Parts for food industry such as dough rolls, rolling rolls, conveyors and hoppers; Industrial goods such as rolls for office automation (OA), OA belts, separation hooks for OA, papermaking rolls, and calender rolls for film production; Molds such as molds for molding foamed styrol, molds, molds for molds such as molds for producing plywoods and lacquers, industrial containers (especially for semiconductor industries), and tools using saws and saws. Household appliances such as irons, scissors, kitchen knives; Plain bearings of metal foil, electric wire, food processing machine, packing machine, textile machine, sliding parts of camera and watch, automobile parts such as pipe, valve, bearing, snow shovel, plow and suit.

The coated article having such a fluorine-containing laminate is also one of the present invention.

The fluorine-containing laminate of the present invention has the above-mentioned constitution, and thus has no coating film defect and is excellent in corrosion resistance. Such a fluorine-containing laminate can be particularly preferably used for a cooking apparatus, a kitchen utensil, and the like.

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 "%" and "part" respectively indicate mass% and mass part.

Production Example 1 Production of aqueous dispersion of polyether sulfone resin

60 parts of polyethersulfone resin [PES] having a number average molecular weight of about 24,000 and 60 parts of deionized water were stirred in a ceramic ball mill for about 10 minutes until particles containing PES were completely pulverized. Subsequently, 180 parts of N-methyl-2-pyrrolidone (hereinafter referred to as NMP) was added and pulverized for another 48 hours to obtain a dispersion. The obtained dispersion was further pulverized in 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 PES-containing particles in the PES aqueous dispersion was 2 탆.

Production Example 2 Production of aqueous dispersion of polyamide-imide resin

A PAI varnish (containing 71% of NMP) of polyamide-imide resin [PAI] having a solid content of 29% was poured into water to precipitate PAI. This was pulverized in a ball mill for 48 hours to obtain a PAI aqueous dispersion. The solid content of the resulting PAI aqueous dispersion was 20%, and the average particle diameter of PAI in the PAI aqueous dispersion was 2 占 퐉.

Production Example 3 Preparation of coating composition (i) for primer

The PES aqueous dispersion obtained in Production Example 1 and the PAI aqueous dispersion obtained in Production Example 2 were mixed so that the PES was 75% of the total solids content of PES and PAI, and tetrafluoroethylene homopolymer [TFE homopolymer] aqueous (Average particle diameter: 0.28 탆, solid content: 60%, polyether-based nonionic surfactant (polyoxyethylene tridecyl ether) as a dispersing agent in an amount of 6% based on the TFE homopolymer) was used as PES and PAI And 25% of the total solid content of the TFE homopolymer, 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 nonylphenyl ether) 6% of the solid content of the polymer was added to obtain an aqueous dispersion having a solid content of 34% of the TFE homopolymer.

Example 1

The inner surface of a metal container having an aluminum content of 2 liters was degreased with acetone, and then sand blasted so as to have a surface roughness Ra value of 2.0 to 3.0 占 퐉 as measured in accordance with JIS B 1982 to roughen the surface. After the dust on the surface was removed by air blow, the coating composition (i) for primer obtained in Production Example 3 was sprayed on a RG-2 type gravity spray gun (trade name, manufactured by Anest Iwata Co., Ltd., Diameter: 1.0 mm) was used and sprayed at an injection pressure of 0.2 MPa. The obtained aluminum-coated film was dried at 80 to 100 캜 for 15 minutes and cooled to room temperature. A PFA powder coating material (trade name: NEOFLON PFA ACX-34, manufactured by Daikin Industries, Ltd., average particle diameter of about 23 mu m) was applied on the obtained primer coating film so as to have an applied voltage of 50 kV and a pressure of 0.08 MPa, and fired at 380 占 폚 for 20 minutes. After cooling to room temperature, a PFA water-based paint (trade name: NEOPLON PFA AD-2CRER, manufactured by Daikin Industries, Ltd., average particle diameter of PFA: 0.3 μm) was fired to form an RG- Spraying gun (trade name, manufactured by Anest Iwata Co., Ltd., nozzle diameter 1.0 mm) was used and spray coating was performed at an injection pressure of 0.2 MPa. The obtained coating film was dried at 80 to 100 캜 for 15 minutes and then fired at 380 캜 for 20 minutes to obtain a coating pan for testing. On the inner surface of the obtained coating pan for test, a primer layer, a PFA layer (intermediate coating layer) and a layer containing PFA having a small particle diameter (upper coating layer) were formed on aluminum (substrate).

(Assessment Methods)

The coating film on the inner surface of the coating pan thus obtained was evaluated in the following manner.

Film thickness

(LZ-300C, manufactured by KITS SCIENCE RESEARCH INSTITUTE).

Pin hole test

A pinhole test was conducted to investigate the presence or absence of coating film defects in the laminate. A mixed solution containing isopropyl alcohol / water = 1/3 (weight ratio) was filled in the test paint pot, and a voltage of 125 V was applied between the test paint pot and the mixed solution. The resistance value was measured using a digital insulation resistance meter Model MY40 manufactured by Yokogawa Meter & The larger the resistance value, the smaller the coating film defects (pinholes) and judged that the corrosion resistance was good.

The pinhole test described above was performed on the coating pan for test obtained in Example 1. [ The results are shown in Table 1. The resistance value of the pinhole test was infinite, and the coating film on the inner surface of the coating pan for test obtained in Example 1 was free from coating film defects.

Example 2

(Trade name: NEOPLON FEP ND-110, manufactured by Daikin Industries, Ltd., average particle size of FEP manufactured by Daikin Industries, Inc., trade name: Neopuron PFA AD-2CRER Diameter: 0.13 mu m) was used in place of the above-prepared coating pan. On the inner surface of the obtained coating pan for test, a layer (upper coating layer) containing a primer layer, a PFA layer (intermediate coating) and a small particle diameter FEP was formed on aluminum (substrate).

A pinhole test was conducted on the obtained coating pan for testing in the same manner as in Example 1. The results are shown in Table 1. The resistance value of the pinhole test was infinite, and the coating film on the inner surface of the coating pan for test obtained in Example 2 was free from coating film defects.

Comparative Example 1

PFA aqueous coating material (trade name: NEOPLON PFA AD-2CRER, manufactured by Daikin Industries, Ltd.) was coated so as to have a film thickness of about 45 mu m after baking the PFA powder coating material (trade name: NEOPLON PFA ACX- A coating film on the inner surface of the coating pan for test was prepared in the same manner as in Example 1. [ A primer layer and a PFA layer (intermediate coating layer) were formed on the inner surface of the obtained coating pan for testing.

A pinhole test was conducted on the obtained coating pan for testing in the same manner as in Example 1. The results are shown in Table 1. The resistance value of the pinhole test was 1.2 M OMEGA, and the coating film on the inner surface of the coating pan obtained in Comparative Example 1 had coating film defects.

Comparative Example 2

(PFA AD-2CRER, manufactured by Daikin Industries, Ltd.) was applied without applying a PFA powder coating material (trade name: NEOPLON PFA ACX-34, manufactured by Daikin Industries) , A painting pot for testing was prepared in the same manner as in Example 1. [ A primer layer and a PFA layer (upper coating layer) having a small particle diameter were formed on the inner surface of the obtained coating pan for testing.

A pinhole test was conducted on the obtained coating pan for testing in the same manner as in Example 1. The results are shown in Table 1. The resistance value of the pinhole test was 0.1 M OMEGA, and the coating film on the inner surface of the coating pan obtained in Comparative Example 2 had coating film defects.

Comparative Example 3

A coating film on the inner surface of a coating pan for testing was produced in the process of Example 1 described in JP-A-11-342072.

A pinhole test was conducted on the obtained coating pan for testing in the same manner as in Example 1. The results are shown in Table 1. The resistance value of the pinhole test was 1.2 M OMEGA, and the coating film on the inner surface of the coating pan obtained in Comparative Example 3 had a coating film defect.

The abbreviations in Table 1 are as follows.

Production Example 3: The coating composition (i) for the primer obtained in Production Example 3

ACX-34: manufactured by Daikin Industries, Ltd., PFA powder coating

AD-2CRER: manufactured by Daikingo, PFA aqueous paint

ND-110: manufactured by DaikinGo, FEP aqueous paint

EK-1959DGN: manufactured by Daikin Industries, Ltd., aqueous primer

ACX-31: manufactured by DaikinGo, PFA powder coating material

EK-4300CR: manufactured by Daiking Corporation, aqueous PTFE dispersion

≪ Industrial applicability >

Since the fluorine-containing laminate of the present invention has the above-mentioned constitution, it has no coating film defect and is excellent in corrosion resistance and can be suitably used particularly for coated articles such as cooking utensils and kitchen utensils.

Claims (11)

(Ii) comprising a base material, a primer layer (A), a melt-processible fluorine-containing polymer (b) having a melt viscosity of 10 ⁶ (Pascal-second) or less at a temperature 50 ° C higher than the melting point, (Iii) a layer (B) containing a melt-processable fluorine-containing polymer (c) having a melt viscosity of 10 ⁶ (Pascal-second) or less at a temperature higher than the melting point by 50 ° C, And a layer (C) formed of a fluorine-
Wherein the powder coating (ii) has an average particle diameter of 5 to 30 占 퐉 and the average particle diameter of the particles containing the melt-processible fluoropolymer (c) is 0.01 to 1.0 占 퐉,
Characterized in that the base material, the primer layer (A), the layer (B) and the layer (C) are laminated in this order and the layer (C) is laminated adjacent to the layer (B) Fluorine-containing laminate. The recording medium according to claim 1, wherein the primer layer (A) has a thickness of 5 to 30 占 퐉, the layer (B) has a thickness of 10 to 90 占 퐉, the layer (C) By weight of the fluorine-containing polymer. The fluorine-containing laminate according to claim 1 or 2, wherein the primer layer (A) comprises a heat-resistant resin having a continuous usable temperature of 150 ° C or higher with the fluorine-containing polymer (a). The heat-resistant resin according to claim 3, wherein the heat resistant resin is selected from the group consisting of a polyamideimide resin, a polyimide resin, a polyether sulfone resin, a polyetherimide resin, a polyetheretherketone resin, an aromatic polyester resin, and a polyarylene sulfide resin By weight of the fluorine-containing polymer. The heat-resistant resin according to claim 3, wherein the heat-resistant resin comprises at least one resin selected from the group consisting of a polyethersulfone resin, a polyamideimide resin and a polyimide resin,
Wherein the polyethersulfone resin is 65 to 85% by mass of the total amount of both the polyethersulfone resin and a polyamideimide resin, a polyimide resin, or both a polyamideimide resin and a polyimide resin. The fluorine-containing laminate according to claim 3, wherein the heat-resistant resin is 10 to 50% by mass of the sum of the solid content of the heat-resistant resin and the fluorine-containing polymer (a). The fluorine-containing polymer composition according to claim 1 or 2, wherein the melt-processible fluorine-containing polymer (c) is selected from the group consisting of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer and a tetrafluoroethylene / hexafluoropropylene copolymer And the fluorine-containing polymerizable compound is at least one selected from the group consisting of fluorine-containing compounds. The fluorine-containing polymer composition according to claim 3, wherein the fluorine-containing polymer (a) is at least one selected from the group consisting of tetrafluoroethylene homopolymer, modified polytetrafluoroethylene, tetrafluoroethylene / hexafluoropropylene copolymer and tetrafluoroethylene / perfluoro Vinyl ether) copolymer. The fluorine-containing laminate is at least one selected from the group consisting of a fluorine-containing vinyl ether copolymer and a vinyl ether copolymer. The process for producing a fluorine-containing polymer according to claim 1 or 2, wherein the melt-processible fluorine-containing polymer (b) is a copolymer comprising a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer and a tetrafluoroethylene / hexafluoropropylene copolymer And the fluorine-containing polymerizable compound is at least one selected from the group consisting of fluorine-containing compounds. (1) for forming a primer coating film (Ap) by applying a primer coating composition (i) on a substrate,
(Ii) containing a melt-processible fluorine-containing polymer (b) having a melt viscosity of 10 ⁶ (Pascal-second) or less at a temperature higher than the melting point by 50 ° C is applied on the primer coating film (Ap) A step (2) of forming a coating film (Bp) containing no filler,
(Iii) containing particles containing a melt-processible fluorine-containing polymer (c) having a melt viscosity of 10 ⁶ (Pascal-second) or less at a temperature higher by 50 ° C than the melting point, on the coating film (Bp) A step (3) of forming a coating film (Cl) by coating, and
The substrate, the primer layer (A), the layer (B), and the layer (C) are fired by firing a coating film laminate including the primer coating film (Ap), the coating film (Bp) (4) of forming a fluorine-containing laminate containing a fluorine-
Wherein the powder coating (ii) has an average particle diameter of 5 to 30 占 퐉 and the average particle diameter of the particles containing the melt-processible fluoropolymer (c) is 0.01 to 1.0 占 퐉. Gt; delete