JP2005335184A - Fluoroplastic-containing laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluoroplastic-containing laminate good in interlaminar heat-resistant adhesion and the heat-resistant adhesion with an article to be coated. <P>SOLUTION: The fluoroplastic-containing laminate contains a primer layer (1) obtained by the coating with a primer composition and a filler-containing fluoroplastic resin layer (2). The primer composition is composed of an amide group-containable polymer compound (A), an anti-oxidizing substance (B) and a fluoroplastic (C) and the amide group-containable polymer compound (A) is an amide group-containing polymer (a1) having an amide group and an aromatic ring and/or an amide group containing polymer precursor (a2) to be changed to the amide group-containing polymer (a1) by baking at the time of coating. The anti-oxidizing substance (B) is 0.1-20 mass% of the sum total of the amide group-containable polymer compound (A) and the anti-oxidizing substance (B). The filler-containing fluoroplastic resin layer (2) is composed of a fluoroplastic (D) and a filler. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a fluororesin-containing laminate.

Since the fluororesin is excellent in wear resistance, heat resistance, corrosion resistance, etc., it can be used for coating various objects to be coated. However, since the fluororesin has poor adhesion to an object to be coated made of metal, ceramic or the like because of its non-adhesiveness, (1) a method of coating the fluororesin by performing an electrostatic powder spraying method (for example, Patent Document 1), (2) A method has been proposed in which a primer having an affinity for both the fluororesin layer and the object to be coated is applied to the object to be coated in advance.

In the case of using a primer, the composition made of a fluororesin applied on the primer layer needs to be fired at a temperature equal to or higher than the melting point of the fluororesin. Therefore, the primer is required to have heat-resistant adhesion that can maintain the adhesion to the object to be coated even after the baking at this high temperature.

To date, chromium phosphate-based primers having excellent resistance to long-term high-temperature firing have been widely used as primers excellent in heat-resistant adhesion used for coating fluoropolymers. However, awareness of environmental problems has increased, and there has been a strong demand for many years to develop a chromium-free primer that does not contain hexavalent chromium and has strong heat-resistant adhesion comparable to that of a chromium phosphate primer.

Conventionally, combinations of fluororesin and various binder resins have been studied as chromium-free primers. As the binder resin, it has been proposed to use polyphenylene sulfide [PPS] from the viewpoint of heat resistance. As a laminate obtained by laminating a fluororesin using PPS, for example, an insulation-coated metal tube and an insulation-coated joint obtained by applying a heat-resistant paint containing PPS and a fluororesin have been proposed (for example, Patent Documents). 2). However, PPS has a problem in that it has poor compatibility with the fluororesin and has insufficient adhesion to the fluororesin layer.

In order to improve the adhesion with the fluororesin layer, a binder resin in a chromium-free primer has been proposed that contains PPS and PAI and / or polyimide [PI] in a specific ratio (for example, patents). (Ref. Literature 3, Patent Literature 4, and Patent Literature 5). However, chromium-free primers having these binder resins have problems such as poor heat-resistant adhesion and low durability against hot water when fired for a long time.

When powder coating a fluororesin on a metal surface, the polyethersulfone, PAI and / or PI, fluororesin and metal powder are dissolved or dissolved in an organic solvent for the purpose of improving the adhesion between the metal surface and the fluororesin layer. A primer composition for coating a fluororesin obtained by dispersing has been proposed (for example, see Patent Document 6). However, this primer composition for coating a fluororesin has a problem that the adhesion between the metal surface and the fluororesin layer obtained by powder coating is still insufficient.

JP 50-156554 A JP-A-3-268940 JP-A-53-74532 US Pat. No. 5,789,083 Japanese Patent Laid-Open No. 8-322732 JP-A-6-264000

In view of the above-mentioned present situation, the present invention provides a fluororesin-containing laminate that has improved heat-resistant adhesion to the interlayer and to-be-coated objects, even though the primer layer does not contain hexavalent chromium serving as a binder component. The purpose is to provide.

The present invention is a fluororesin-containing laminate comprising a primer layer (1) obtained by coating a primer composition and a filler-containing fluororesin layer (2), the primer composition comprising an amide group Or an amide group-containing polymer compound (A) having an amide group, an antioxidant substance (B) capable of suppressing oxidation of the amide group, and a fluororesin (C) The amide group-containing polymer compound (A) is coated with the amide group-containing polymer (a1) having an amide group and an aromatic ring, and / or the primer composition. An amide group-containing polymer precursor (a2) that changes to the amide group-containing polymer (a1) upon firing, and the antioxidant substance (B) includes the amide group-containing polymer compound (A) and It is 0.1-20 mass% of the sum total with the antioxidant substance (B), The said filler-containing fluororesin layer (2) consists of a fluororesin (D) and a filler, It is characterized by the above-mentioned. It is a fluororesin-containing laminate.

The present invention is a duct including a hollow metal tube and the fluororesin-containing laminate lined on the inner surface of the hollow metal tube, the hollow metal tube, the primer layer (1) and the filler-containing fluororesin layer ( 2) is a duct characterized by being laminated in this order.
The present invention is described in detail below.

The fluororesin-containing laminate of the present invention comprises a primer layer (1) and a filler-containing fluororesin layer (2).
The primer layer (1) is obtained by coating a primer composition.
The primer composition is a coating composition comprising an amide group-containing polymer compound (A), an antioxidant substance (B), and a fluororesin (C).

In this specification, “coating” means a series of steps comprising applying to a coating object such as an object to be coated, drying as necessary, and then firing.
In the present specification, the firing is heating at a temperature equal to or higher than the melting point of the main polymer component in the fluororesin-containing laminate of the present invention. The heating temperature includes the amide group-containing polymer compound (A), the antioxidant substance (B), the fluororesin (C), the fluororesin (D), and the fluorine that will be described later if desired. It varies depending on each melting point of the resin (E).

The amide group-containing polymer (A) is obtained by baking the amide group-containing polymer (a1) having an amide group and an aromatic ring and / or the primer composition. It is an amide group containing polymer precursor (a2) which changes to a containing polymer (a1).

The amide group-containing polymer (a1) is usually a polymer having an amide group (—NH—C (═O) —) in the main chain or side chain and an aromatic ring in the main chain.
The amide group-containing polymer (a1) is preferably polyamideimide [PAI], polyamide, and / or polyamic acid (polyamic acid).

The PAI is a polycondensate having an amide group, an aromatic ring, and an imide group. The PAI is not particularly limited, and for example, in addition to the conventionally known PAI, those in which an amide group is introduced by oxidizing polyimide [PI] can be used.
The polyamide is a polycondensate having an amide bond (—NH—C (═O) —) in the main chain. The polyamide is not particularly limited, and examples thereof include aliphatic polyamides such as nylon 6, nylon 66, nylon 11, and nylon 12; aromatic polyamides such as polyparaphenylene terephthalamide and polymetaphenylene isophthalamide. .
The polyamic acid is a polycondensate having an amide group and a carboxyl group or a carboxyl group derivative. The polyamic acid is not particularly limited, and examples thereof include a polyamic acid having a molecular weight of thousands to tens of thousands.

The amide group-containing polymer precursor (a2) is changed to the amide group-containing polymer (a1) by firing when the primer composition is applied.
The above-mentioned “firing at the time of applying the primer composition” includes (i) “firing” usually performed after applying the primer composition and before coating a filler-containing fluororesin composition described later, (ii) After firing (i), “baking” when coating a filler-containing fluororesin composition described later, or (iii) filler-containing fluororesin composition described later without firing (i) above It is a “firing” when coating the paint, and is a concept that can include any of the firings (i) to (iii).
As described above, the amide group-containing polymer precursor (a2) is changed to the amide group-containing polymer (a1) by firing when the primer composition is applied. In this firing, the amide group-containing polymer precursor (a2) Since the aromatic ring of the polymer (a1) does not usually change, it has an aromatic ring, but it does not have an amide group before applying the primer composition and starting firing. is there.
In the present specification, the polymer compound having an amide group and further having an aromatic ring before applying the primer composition and starting baking is the amide group-containing polymer (a1). It corresponds to.

The amide group-containing polymer precursor (a2) is not particularly limited as long as it changes into the amide group-containing polymer (a1) by applying and baking the primer composition, and examples thereof include PI. May be.
The PI can be oxidized when the primer composition is applied and baked at a high temperature for a long time to introduce an amide group into the main chain. The amide group-containing polymer (a1) obtained by introducing an amide group into the PI is PAI or polyamic acid. In order to be PAI, all of the imide groups in the main chain of PI were converted to amide groups. The polyamic acid may be a polyamic acid obtained by converting all of the imide groups in the main chain of PI into amide groups and carboxyl groups.

The method for introducing an amide group into the PI is not particularly limited. For example, a method of opening the imide group (imide ring) of PI by oxidation, or hydrolysis by causing an alkali to act on the imide group (imide ring) of PI. Methods and the like.
In the present specification, a site on a molecular structure into which an amide group is to be introduced, for example, an imide group that is changed to an amide group by the above-described oxidation may be referred to as an amide group introduction site.

The amide group-containing polymer compound (A) has an amide group or has an amide group.
The above “becomes having an amide group” means that the amide group-containing polymer compound (A) is not necessarily present at the time when the amide group-containing polymer compound (A) is blended in order to prepare the primer composition. Although it does not need to have an amide group, it means that a chemical change is caused by baking at the time of applying the primer composition described above, and the amide group is introduced before the baking is completed.

In the present specification, the above-mentioned "has an amide group or will have an amide group" means that at the time of blending the amide group-containing polymer compound (A) in order to prepare the primer composition, It is a concept that can include any of those having an amide group and no amide group introduction site, those having no amide group and having an amide group introduction site, those having an amide group and having an amide group introduction site. is there. That is, the primer composition may contain both the amide group-containing polymer (a1) and the amide group-containing polymer precursor (a2), or only one of them. Also good.

The average particle diameter of the particles composed of the amide group-containing polymer compound (A) is more preferably 200 μm and more preferably 150 μm when the primer composition is used as a powder coating to be described later. If the average particle diameter of the particles comprising the amide group-containing polymer compound (A) is within the above range, the preferable lower limit can be set to 0.01 μm, and the more preferable lower limit can be set to 0.1 μm.
In the present specification, the average particle diameter is a value that can be measured by a laser measurement method.

The antioxidant substance (B) can suppress oxidation of the amide group. The antioxidant substance (B) has a redox potential lower than the redox potential of the amide group and is comparable to the redox potential of the imide group or compared to the redox potential of the imide group. A higher one is preferable, and a higher one is more preferable than the redox potential of the imide group.

It is considered that the antioxidant substance (B) can delay the oxidation of the amide group by being auto-oxidized in preference to the oxidation of the amide group. As said antioxidant substance (B), it is thought that the substance with a low oxidation state is preferable from the point which can fully suppress the oxidation of the said amide group. As said antioxidant substance (B), while being able to suppress the oxidation of the said amide group, it is more preferable that it is a heat resistant substance. If the antioxidant substance (B) is a heat-resistant substance, the antioxidant substance (B) is unlikely to be decomposed or deteriorated even if firing is performed for a long time when the primer composition is applied. Oxidation of the amide group can be continuously suppressed, and adhesion with the object to be coated by the amide group-containing polymer compound (A) can be maintained.

The antioxidant substance (B) may have a reducing ability to reduce the oxidized amide group in addition to the self-oxidizing ability to self-oxidize in preference to the oxidation of the amide group.
The antioxidant substance (B) may have a property of suppressing the oxidation of the object to be coated in addition to the property of suppressing the oxidation of the amide group.

Examples of the antioxidant substance (B) include polyarylene sulfide [PAS]; nitrogen-containing compounds; metals such as tin, zinc and phosphorus; sulfur and the like.
The PAS is not particularly limited, and examples thereof include polyphenylene sulfide ketone, polyphenylene sulfide sulfone, polybiphenylene sulfide, and polyphenylene sulfide [PPS]. Among these, PPS is preferably used. PAS is preferably used when the use of amines or elution of metal ions is disliked in semiconductor manufacturing processes.

The “nitrogen-containing compound” is a compound having a nitrogen atom in the molecule, and can suppress both oxidation of the amide group and oxidation of the object to be coated.
Examples of the nitrogen-containing compound include amine compounds, benzotriazole compounds, nitrogen sulfur-containing compounds, and the like.

The amine compound is a compound having an amino group, and the amino group may form a salt such as a metal salt. Although it does not specifically limit as said amine compound, Aromatic amines are preferable at the point from which the high temperature stability above 250 degreeC is desired.
As the aromatic amines, those having a phenyl group and / or naphthyl group are preferable, and the aromatic amines having a phenyl group and / or naphthyl group are not particularly limited, and examples thereof include dinaphthylamine and phenyl-α-naphthylamine. , Phenyl-β-naphthylamine, diphenyl-p-phenylenediamine, phenylcyclohexyl-p-phenylenediamine, and the like.

The benzotriazole-based compound is a compound having a chemical structure having benzotriazole as a basic skeleton, and may form a salt such as a metal salt. The benzotriazole-based compound is not particularly limited, and examples thereof include benzotriazole, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tetraoctylphenyl) benzotriazole, and the like. It is done.

The nitrogen-sulfur-containing compound is a compound having a nitrogen atom and a sulfur atom, and may form a salt such as a metal salt. The nitrogen-sulfur-containing compound is not particularly limited, and examples thereof include benzothiazole compounds, sulfenamide compounds, and thioureas. The benzothiazole compound is not particularly limited as long as it is a compound having benzothiazole as a basic skeleton. For example, 2-mercaptobenzothiazole, di-2-benzothiazole disulfide, 2- (N, N′-diethylthiocarbamoyl) Thio) benzothiazole, di-2-benzothiazolyl disulfide and the like.

The sulfenamide-based compound is not particularly limited as long as it is a compound having a sulfenamide group. For example, N, N′-cyclohexyl-benzothiazolylsulfenamide, N-tert-butyl-2-benzothia Zolylsulfenamide, N-oxydiethylene-2-benzothiazolylsulfenamide, N, N'-dicyclohexyl-2-benzothiazolylsulfenamide, N, N'-diisopropylbenzothiazole-2-sulfenamide, etc. Is mentioned.
In the present specification, the sulfenamide-based compound is a concept including a compound having a sulfenamide group and a structural portion having benzothiazole as a basic skeleton.

The thioureas are preferably thioureas in which at least one hydrogen atom bonded to the nitrogen atom may be substituted with a saturated or unsaturated hydrocarbon group having 1 to 6 carbon atoms. Such thioureas Is not particularly limited, and examples thereof include N, N′-diethylthiourea, N, N′-dibutylthiourea, thiourea, and N, N′-diphenylthiourea.

As the nitrogen-containing compound, a benzothiazole-based compound is preferably used, and a zinc-based antioxidant that is a salt with zinc is particularly preferably used among the benzothiazole-based compounds.

As said antioxidant substance (B), PAS and / or a nitrogen-containing compound are preferable, and PAS is more preferable.
As the antioxidant substance (B), it is preferable to use the nitrogen-containing compound when the object to be coated is made of an oxide film rapid-forming metal that easily forms an oxide film, and the nitrogen-containing compound and the PAS are used. Is preferably used in terms of improving the adhesion to the object to be coated.
In the present specification, the oxide film rapid-forming metal is a metal that forms an oxide film at least as fast as or faster than stainless steel by firing at least in the coating of the primer composition. The oxide film rapid forming metal may be one in which an oxide film has already been formed when the primer composition is applied as an object to be coated. Examples of the oxide film rapid-forming metal include stainless steel described later.

As the antioxidant substance (B), when the object to be coated is made of a metal that slowly forms an oxide film, the nitrogen-containing compound may be used. Thus, the nitrogen-containing compound does not have to be used, and does not necessarily have the property of suppressing the oxidation of the object to be coated, but it does not oxidize the amide group. It is sufficient to use what has the property to suppress, for example, you may use only PAS.
In the present specification, the oxide film slow-forming metal is a metal that forms an oxide film slower than stainless steel. Examples of the oxide film slow-forming metal include aluminum and iron.

When the primer composition is used as the above-mentioned powder coating, the average particle diameter of the particles made of the antioxidant substance (B) is in the same range as the particles made of the amide group-containing polymer compound (A). Can be inside.

As said antioxidant substance (B), 1 type (s) or 2 or more types can be used in combination.
When PAS and other antioxidant substances are used in combination as the antioxidant substance (B), the other antioxidant substances include those other than PAS among the above-mentioned antioxidant substances (B). Among these, nitrogen-containing compounds are preferably used.
Examples of the other antioxidant substances include nitrogen-containing compounds, metals such as tin, zinc, and phosphorus; sulfur and the like.
The PAS and the other antioxidant substance are preferably combined in a mass ratio such that PAS: other antioxidant substance = 50: 50 to 200: 1. PAS: other antioxidant substance It is more preferable to combine so that it may become = 50: 50-99: 1.

The said antioxidant substance (B) is 0.1-20 mass% of the sum total of the said amide group containing high molecular compound (A) and the said antioxidant substance (B). If it exceeds 20% by mass, the adhesion after hot water treatment tends to decrease, and if it is less than 0.1% by mass, the adhesion after heat treatment tends to decrease.
When used in combination, the mass of the antioxidant substance (B) is the total mass of all the antioxidant substances (B) combined.

When PAS is used alone as the antioxidant substance (B), PAS is preferably 1 to 20% by mass of the total of the amide group-containing polymer compound (A) and PAS. If it is less than 1% by mass, the adhesion after heat treatment tends to be reduced. When it exceeds 20 mass%, the adhesive force after a hot-water process will fall easily. The preferable lower limit is 3% by mass, the preferable upper limit is 18% by mass, the more preferable lower limit is 5% by mass, and the more preferable upper limit is 15% by mass.

When a nitrogen-containing compound is used alone as the antioxidant substance (B), the nitrogen-containing compound is 0.1 to 5 mass in total of the amide group-containing polymer compound (A) and the nitrogen-containing compound. % Is preferred. If it is less than 0.1% by mass, the adhesion after heat treatment tends to be reduced. When it exceeds 5 mass%, the initial adhesion strength and the adhesion strength after the hot water treatment tend to be reduced. A more preferred upper limit is 3% by mass, and a still more preferred upper limit is 1% by mass.

The primer composition is a coating composition comprising the amide group-containing polymer compound (A), the antioxidant substance (B), and a fluororesin (C).
The primer composition is coated with the first layer mainly composed of the fluororesin (C), and the amide group-containing polymer compound (A) and the antioxidant substance (B) as the main components. The primer layer (1a) divided into the two-layer structure of the second layer can be formed.

In the present specification, the primer layer (1a) divided into the two-layer structure is said to be “divided into a two-layer structure” for the sake of convenience, but actually, the amide group-containing polymer compound (A) is closer to the object to be coated. And the concentration of the antioxidant substance (B) is high, and the concentration of the fluororesin (C) is increased instead of the antioxidant substance (B) as it is away from the object to be coated, and on the outermost surface of the primer layer (1) It is considered that the fluororesin (C) is present at a high concentration. Therefore, depending on the blending amount of each component, the primer layer (1) is composed of a layer made of a fluororesin (C) and a layer made of an amide group-containing polymer compound (A) and an antioxidant substance (B). There may be a layer between the amide group-containing polymer compound (A) and the fluororesin (C) that should be called an intermediate layer.
Since the fluororesin-containing laminate of the present invention has good compatibility between the fluororesin (C) in the first layer and the fluororesin (D) present in the filler-containing fluororesin layer (2), the primer The adhesion between the layer (1) and the filler-containing fluororesin layer (2) is excellent.

In the primer composition, the fluororesin (C) preferably has a baking temperature of 300 ° C. or higher during coating.
The firing temperature during the coating is generally a temperature equal to or higher than the higher one of the melting point of the fluororesin (C) and the melting point of the fluororesin (D) described later. The firing at the time of coating may be the same as the “baking at the time of coating the primer composition” described above for the amide group-containing polymer precursor (a2).
The primer composition is less likely to cause a decrease in adhesion with an object to be coated even after firing for a long time of several tens of hours at a temperature of 300 ° C. or higher. Such excellent heat-resistant adhesion can be achieved conventionally only by using a chromium-based primer, but the above-mentioned primer composition does not require the use of hexavalent chromium or a hexavalent chromium compound. Excellent heat-resistant adhesion can be achieved.

The fluororesin (C) is made of a polymer obtained by polymerizing a monomer having fluorine. In the fluororesin (C), the polymer may be present alone or in combination of two or more.
Examples of the fluororesin (C) include chlorotrifluoroethylene [CTFE], trifluoroethylene, tetrafluoroethylene [TFE], hexafluoropropylene [HFP], vinylidene fluoride [VdF], and perfluoro (alkyl vinyl). It is preferably a fluorine-containing polymer obtained by polymerizing one or more fluorine-containing monomers selected from the group of fluorine-containing monomers consisting of ether [PAVE]. This fluorine-containing polymer is one or two or more fluorine-free monomers selected from the above-mentioned one or two or more fluorine-containing monomers and a fluorine-free monomer group such as ethylene and propylene. And may be obtained by copolymerization of

The fluororesin (C) is more preferably made of a tetrafluoroethylene copolymer in terms of corrosion resistance.
In the present specification, the “tetrafluoroethylene copolymer” is obtained by polymerizing TFE and fluorine-containing monomers and / or fluorine-free monomers other than TFE in the fluorine-containing monomer group described above. It is the obtained polymer. You may use 1 type (s) or 2 or more types as a fluorine-containing monomer other than said TFE, and the said fluorine-free monomer, respectively.

As the fluororesin (C), a resin having a melting point lower than the firing temperature at the time of coating and having heat resistance at the firing temperature is more preferable.
As the fluororesin (C), a perfluoro resin is preferably employed because it has both corrosion resistance and heat resistance.
The perfluoro resin is usually a resin that requires a baking temperature of 300 ° C. or higher, and is obtained by polymerizing perfluoroolefin with perfluorovinyl ether and / or a small amount of a comonomer. It consists of coalescence. It does not specifically limit as said perfluoro olefin, For example, TFE, HFP, etc. are mentioned. The perfluorovinyl ether is not particularly limited, and examples thereof include perfluoro (methyl vinyl ether), perfluoro (ethyl vinyl ether), and perfluoro (propyl vinyl ether).

As said trace amount comonomer, the said fluorine-containing monomer which is neither perfluoroolefin nor perfluoro vinyl ether, and / or a fluorine-free monomer can be used 1 type, or 2 or more types. The repeating unit derived from the trace comonomer in the molecular chain of the perfluoro polymer is preferably less than 10 mol% of the total monomer units of the perfluoro polymer.

The adhesion between the primer layer (1) and the filler-containing fluororesin layer (2) can be improved by using a resin made of a polymer having a terminal functional group as the fluororesin (C).

There are no particular restrictions regarding the terminal functional groups, e.g., -COOR ^{1 (R 1} represents a hydrogen atom, an alkyl group of 1 to 5 carbon atoms, or represents a perfluoroalkyl group having 1 to 3 carbon atoms.), —COF, —CONH ₂ , —CH ₂ OH, —COOM ¹ , —SO ₄ M ² , —SO ₃ M ³ (M ¹ , M ² and M ³ may be the same or different and may be a group I atom or a monovalent cation. Represents an atomic group capable of becoming an ion.), —SO ₄ M ⁴ _1/2 , —SO ₃ M ⁵ _1/2 (M ⁴ and M ⁵ are the same or different and are a transition of a group II atom, iron, etc. Represents an atomic group that can be a metal or a divalent cation.). Examples of the group I atom include a hydrogen atom, a sodium atom, and a potassium atom, and examples of the atomic group that can be a monovalent cation include an ammonium group. Examples of the group II atom include calcium and magnesium. As a transition metal, iron etc. are mentioned, for example.

The amount of the terminal functional group is preferably in the range of 50 to 100,000 per million carbon atoms in the polymer molecular chain of the fluororesin (C). When the number is less than 50, the adhesive force tends to be reduced, and when it exceeds 100000, foaming during firing becomes violent and a coating film defect is likely to occur.
The amount of the terminal functional group is more preferably 100 per million carbon atoms in the polymer molecular chain of the fluororesin (C), more preferably 500 is the lower limit, and more preferably 50,000 is the upper limit. The upper limit is more preferably 10,000.
The amount of the terminal functional group is a value that can be measured using an infrared spectrophotometer.

The amount of the functional group in the polymer having a terminal functional group can usually be adjusted by selecting an appropriate catalyst, a chain transfer agent and polymerization conditions for polymerization.
The amount of the functional group in the polymer having the terminal functional group can be increased by polymerizing the monomer having the functional group.
When the polymer of the fluororesin (C) obtained by polymerizing the monomer having the functional group as a monomer is appropriately reacted with a reaction reagent such as acid or alkali, or heat-treated, the (terminal) functional group is A part of the chemical structure is changed by the action of the reaction reagent and heat.

As the fluororesin (C), a dispersion or powder obtained by emulsion polymerization or suspension polymerization can be used, and a fine powder obtained by pulverization and further pulverization can be used.

When the fluororesin (C) is used as a powder, the average particle size is preferably 0.1 to 500 μm. When the average particle diameter is less than 0.1 μm, the filler-containing fluororesin layer (2) cannot be made too thick, and when it exceeds 500 μm, the surface smoothness of the primer layer (1) is deteriorated. There is. When making the said filler containing fluororesin layer (2) thin coating etc., the more preferable upper limit of the said average particle diameter is 40 micrometers. When the film thickness of the filler-containing fluororesin layer (2) is used for lining or the like exceeding 200 μm, a more preferable lower limit of the average particle diameter is 25 μm, a more preferable upper limit is 250 μm, and a further preferable lower limit is 40 μm.

When the amide group-containing polymer compound (A) is used as the particle state in the primer composition, the average particle size of the particles made of the fluororesin (C) is the amide group-containing polymer compound (A). It is preferable that the particle diameter is relatively larger than the average particle diameter of the particles made of the above and the particles made of the antioxidant substance (B).
In particular, in the case of a dispersion in which each of these particles is dispersed in a dispersion medium, the average particle diameter of the particles made of the amide group-containing polymer compound (A) is from the above-mentioned antioxidant substance (B). It is preferable that it is 20 micrometers or less similarly to the particle | grains which become. If it is in the said range, a preferable minimum can be 0.01 micrometer and a more preferable minimum can be 0.1 micrometer.

It is preferable that the said fluororesin (C) is 50-90 mass% of the sum total of the said amide group containing high molecular compound (A), the said antioxidant substance (B), and the said fluororesin (C). If it is less than 50% by mass, the adhesion between the primer layer (1) and the filler-containing fluororesin layer (2) tends to be poor, and if it exceeds 90% by mass, the primer layer (1) and the coating layer described later are used. Adhesion with paint tends to deteriorate. A more preferable lower limit is 60% by mass, and a more preferable upper limit is 85% by mass.

The said numerical range is a value about solid content mass of a fluororesin (C). The solid content mass of the fluororesin (C) may be blended with the fluororesin (C) in a liquid form such as a dispersion as described above in preparing the primer composition. It is a value corresponding to the dry mass of the powder obtained by taking out the particles comprising the fluororesin (C) in the liquid.

For the purpose of improving the film-forming property, corrosion resistance, etc. of the primer layer (1), the primer composition contains the amide group-containing polymer compound (A), the antioxidant substance (B), Or what mixed the resin which has the heat resistance of 200 degreeC or more which is not either of fluororesin (C) may be used.
It does not specifically limit as said other resin, For example, polyether sulfone resin, polyether ether ketone resin, polyether ketone resin etc. are mentioned, These can use 1 type (s) or 2 or more types.

The primer composition may contain a specific filler and / or additives described later in order to improve the coating workability and the properties of the primer layer (1) as necessary.
In the primer layer (1), the specific filler is not particularly limited. However, in the present invention, the specific filler is included in the filler-containing fluororesin layer (2), so it is not necessary to include it in the primer layer (1).

The primer composition can be produced by either a powder paint type or a liquid paint type.
In the primer composition, the amide group-containing polymer compound (A) and the antioxidant substance (B) may be dissolved in an appropriate solvent and used as a solution. When the primer layer (1) having a thickness exceeding 100 μm is formed, it is preferably a powder paint type as described later. However, the primer composition is liquid in that it can be uniformly applied to the object to be coated. A paint type is preferred.

As the liquid paint type, an amide group-containing polymer compound (A) and an antioxidant substance (B) are dissolved or dispersed in a dispersion in which particles made of a fluororesin (C) are dispersed in a dispersion medium. In order to increase the film thickness, particles made of an amide group-containing polymer compound (A), particles made of an antioxidant substance (B), and a fluororesin (C) It is more preferable that the particles made of the above are dispersed in a dispersion medium. When the primer composition is a liquid paint type in which the above-mentioned other resin is blended, depending on the type of the dispersion medium and the solubility of the other resin, etc., the primer composition usually contains particles made of the other resin. Dispersed in the above dispersion medium.

As the dispersion medium, water or an organic medium can be used. When water is used as the dispersion medium, a cationic surfactant, an anionic surfactant, or a nonionic surfactant can be dispersed as a dispersant, but it is difficult to remain in the primer layer (1). Nonionic surfactants are preferably used. When water is used as the dispersion medium, a fluorine-based surfactant may be used in combination.
The organic medium is not particularly limited. For example, lower alcohols such as 1-butanol and diacetone alcohol; ketones such as methyl isobutyl ketone and methyl ethyl ketone; esters such as butyl acetate; N-methyl-2-pyrrolidone; Amides such as N, N-dimethylacetamide, N, N-dimethylformamide; aromatic hydrocarbons such as toluene, xylene, trimethylbenzene, methylethylbenzene, propylbenzene, butylbenzene, etc. The above can be used.
As the dispersion medium, a mixed solvent of water and the organic medium can also be used.

The primer composition comprises the fluororesin (C) dispersion, the amide group-containing polymer compound (A) and the antioxidant substance (B), and the other resin used as required, in the organic medium and It can be prepared by, for example, a method of stirring and mixing with a binder resin liquid material dissolved or dispersed in water.
The fluororesin (C) dispersion is obtained by wetting the particles comprising the fluororesin (C) with the above-mentioned dispersion medium and then dispersing with a dispersant such as a nonionic surfactant or an anionic surfactant. The dispersion medium can be obtained by, for example, a method in which the surface tension of the dispersion medium is lowered with a fluorine-based surfactant or the like to disperse particles made of the fluororesin (C).
The stirring and mixing is preferably performed using a pulverizing and dispersing machine such as a basket mill, a dynamo mill, or a ball mill.
After the stirring and mixing, the primer composition may be diluted with a poor solvent as necessary to adjust the viscosity.

In the fluororesin-containing laminate of the present invention, the primer layer (1) preferably has a thickness of 1 to 500 μm. Even if the thickness of the primer layer (1) is less than 1 μm or more than 500 μm, the heat-resistant adhesion tends to be inferior.

The said filler-containing fluororesin layer (2) consists of a fluororesin (D) and a filler.
The filler-containing fluororesin layer (2) may be a single layer or two or more layers. The latter two or more layers are not particularly limited, and examples thereof include those in which the type of fluororesin (D) and / or the type of filler differ between layers. For example, a pigment is used as the filler. If so, the two layers can be colored differently.

As said fluororesin (D), the fluororesin mentioned above about the fluororesin (C) is mentioned, for example.
In the fluororesin-containing laminate of the present invention, the fluororesin (D) is preferably a perfluoro resin in that it has both corrosion resistance and heat resistance. The fluororesin (C) and the fluororesin It is more preferable that both (D) are perfluoro resins.
Since the fluororesin-containing laminate of the present invention contains a large amount of fluororesin (C) on the surface of the primer layer (1), the primer layer (1) and the filler-containing fluororesin layer (2 In order to improve compatibility and adhesion with the fluororesin (D), it is preferable to use a fluororesin (D) having the same or similar composition as the fluororesin (C).
The filler-containing fluororesin layer (2) may contain a fluororesin (C) together with the fluororesin (D) in that the adhesiveness with the primer layer (1) can be improved.

In the present specification, the “filler” is an additive material used for increasing the amount, imparting design, imparting conductivity, reinforcing the coating film, preventing shrinkage, facilitating thick coating, and the like. In the present specification, the filler may be referred to as a “specific filler”. The filler in the present invention is usually non-meltable at the baking temperature when forming the filler-containing fluororesin layer (2) and does not decompose. Moreover, it is incompatible with the fluororesin in the filler-containing fluororesin layer (2).
Examples of the filler include metal oxides such as titanium oxide; pigments such as carbon black; glass fillers; conductive fillers; and glittering materials, but metal oxides, pigments, and glass fillers are preferable.
The filler-containing fluororesin layer (2) may be formed by adding one or more fillers.
It is preferable that the said filler is 0.1-30 mass parts per 100 mass parts of solid content of a fluororesin (D). As for the said filler, it is more preferable that it is 1.0 mass part or more per 100 mass parts of solid content of a fluororesin (D), and it is more preferable that it is 20.0 mass parts or less.

In general, the fluororesin has a large thermal shrinkage rate, and in a thick film by powder coating or the like, the internal stress becomes large and delamination tends to occur. However, the filler-containing fluororesin layer (2) in the present invention is made of a filler. Therefore, thermal shrinkage can be prevented even during baking at a high temperature during coating, and the mechanical strength is also excellent. Therefore, the fluororesin-containing laminate of the present invention is excellent in initial adhesion to the object to be coated, abrasion resistance, corrosion resistance, and chemical resistance, and even if the filler-containing fluororesin layer (2) is thick, Does not spoil the characteristics. In the fluororesin-containing laminate of the present invention, when, for example, a pigment is used as a filler in the filler-containing fluororesin layer (2), the primer layer originally has a dark color such as black or brown. It is possible to express a vivid color excellent in design.

The filler-containing fluororesin layer (2) can be obtained by coating a filler-containing fluororesin composition comprising a fluororesin (D) and a filler by the method described later.
The filler-containing fluororesin composition can be divided into a powder paint type and a liquid paint type depending on the desired film thickness, as in the primer composition described above. In the filler-containing fluororesin composition, a dispersion medium, a dispersant, other resins, and the like can be used as in the primer composition described above.
The filler-containing fluororesin composition is preferably a powder paint from the viewpoint of corrosion resistance (from the viewpoint of increasing the film thickness).
The filler-containing fluororesin composition for forming the filler-containing fluororesin layer (2) may further contain additives as necessary.
In the present specification, “additives” is a concept that does not include the above-described specific filler. The additives are not particularly limited, for example, a leveling agent, a solid lubricant, a pigment dispersant, an anti-settling agent, a moisture absorbent, a surface conditioner, a thixotropic agent, a viscosity conditioner, an antigelling agent, Examples include ultraviolet absorbers, light stabilizers, plasticizers, color separation inhibitors, anti-skinning agents, anti-scratch agents, fungicides, antibacterial agents, anticorrosive agents, antistatic agents, and silane coupling agents.
In this specification, the said anti-corrosive agent means what has the property which does not suppress the oxidation of an amide group, but suppresses the oxidation of to-be-coated object.

The filler-containing fluororesin layer (2) preferably has a film thickness of 200 μm or more.
The fluororesin-containing laminate of the present invention can maintain sufficient adhesion even when the film thickness of the filler-containing fluororesin layer (2) is 200 μm or more, and can be fired for a long time at a high temperature during construction. Especially useful for the necessary lining.

The fluororesin-containing laminate of the present invention can be obtained by laminating the primer layer (1) and the filler-containing fluororesin layer (2) on the object to be coated in this order.

The object to be coated is a target to be coated with the above-described primer composition.
The material to be coated is not particularly limited, and examples thereof include metals such as aluminum, stainless steel [SUS], and iron; heat-resistant resins; ceramics and the like, and those made of metals are preferable. The metal may be a single metal or an alloy, and may be an oxide film rapid-forming metal such as stainless steel, copper, or copper alloy in terms of good adhesion to the primer layer (1). Alternatively, an oxide film slow-forming metal such as aluminum or iron may be used.

The oxide film rapid forming metal is easy to form an oxide film on the surface, and this oxide film has caused a decrease in adhesion to a coating film obtained by coating a conventional paint composition. Conceivable. The above-mentioned primer composition uses a substance that not only suppresses the oxidation of the amide group as the antioxidant substance (B) but also can suppress the oxidation of the object to be coated, so that the object to be coated can quickly form an oxide film. Even if it consists of an electroconductive metal, sufficient adhesiveness between a to-be-coated object and the said primer layer (1) can be obtained.

Prior to the application of the primer layer (1), the object to be coated is one that has been subjected to removal of the resin component and roughening treatment from the point that the adhesion to the object to be coated can be improved. Is preferred. Examples of the method for removing the resin component include a method using an organic solvent, an alkali and the like; a method of decomposing the resin component at a temperature of 300 ° C. or higher.

The primer layer (1) can be formed on the object to be coated by applying the primer composition described above, and optionally drying at 80 to 150 ° C. for 10 to 60 minutes, followed by baking. .
As the method of application, when the above-mentioned primer composition is a liquid paint type, it is preferable to use spray application, application by a roller, etc., and when the above-mentioned primer composition is a powder paint type, electrostatic application It is preferable to use fluid dip coating or rotrining coating.
Although the firing depends on the melting point of the amide group-containing polymer compound (A), the antioxidant substance (B), and the fluororesin (C) in the primer composition, the fluororesin (C ) By heating for 10 to 60 minutes at a temperature equal to or higher than the melting point.
The firing may be performed before the filler-containing fluororesin composition is applied, or before the filler-containing fluororesin composition is applied, and the filler-containing fluororesin composition is applied. You may perform simultaneously with baking of a filler-containing fluororesin composition at the time of subsequent baking.

The filler-containing fluororesin layer (2) is obtained by applying the filler-containing fluororesin composition onto the primer layer (1) and firing at a temperature equal to or higher than the melting point of the fluororesin (D) for 30 to 120 minutes. Can be obtained.
Application | coating of the said filler-containing fluororesin composition can be performed by the same method as the said primer composition.

The fluororesin-containing laminate of the present invention preferably has a total film thickness of 50 to 1500 μm.
The total film thickness is more preferably 200 μm or more, and more preferably 1000 μm or less.
In the present specification, the total film thickness is the sum of the film thickness of the primer layer (1) and the film thickness of the filler-containing fluororesin layer (2), and the fluororesin-containing laminate of the present invention will be described later. When the material-free fluorine resin layer (3) is included, the total is the thickness of the primer layer (1), the film thickness of the filler-containing fluorine resin layer (2), and the filler-free fluorine resin layer (3). .

The fluororesin-containing laminate of the present invention may further contain a filler-free fluororesin layer (3) made of a fluororesin (E) that does not substantially contain a filler.
When the fluororesin-containing laminate of the present invention includes the filler-free fluororesin layer (3), the primer layer (1), the filler-containing fluororesin layer (2), and the filler-free fluororesin layer ( They are laminated in the order of 3).
In the present specification, the “filler” in the above “substantially containing no filler” means the specific filler described above.
In the present specification, the phrase “substantially does not contain a filler” means that the specific filler is 0.5 parts by mass or less with respect to 100 parts by mass of the fluororesin (E). Although the said filler-free fluorine resin layer (3) is based also on the objective laminated | stacked in this invention, the thing which does not contain a specific filler normally is preferable.

As said fluororesin (E), the fluororesin mentioned above about the fluororesin (C) is mentioned, for example.
In the fluororesin-containing laminate of the present invention, the fluororesin (E) is preferably a perfluoro resin in that it has both corrosion resistance and heat resistance.

When the fluororesin-containing laminate of the present invention is a laminate of the filler-free fluororesin layer (3), the filler-containing fluororesin layer (2) and the filler-free fluororesin layer (3 In order to enhance compatibility and adhesion with the fluororesin (E), it is preferable to use a fluororesin (E) having the same or similar composition as the fluororesin (D). Further, the fluororesin-containing laminate of the present invention can have both corrosion resistance and heat resistance, and both the fluororesin (D) and the fluororesin (E) are perfluororesins. More preferably, the fluororesin (C), the fluororesin (D), and the fluororesin (E) are all preferably perfluoro resins.
The non-filler-containing fluororesin layer (3) contains a fluororesin (D) together with the fluororesin (E) in that the adhesiveness with the filler-containing fluororesin layer (2) can be improved. Also good.

The filler-free fluorine resin layer (3) preferably has a thickness of 30 μm or more.
If the said filler-free fluorine resin layer (3) is in the said range, 50 micrometers or more may be sufficient and 1000 micrometers or less may be sufficient.
When the fluororesin-containing laminate of the present invention is formed by laminating the above-described filler-free fluororesin layer (3), it further has excellent corrosion resistance.

The filler-free fluorine resin layer (3) is obtained by coating the filler-free fluorine resin coating composition composed of the fluorine resin (E) on the filler-containing fluorine resin layer (2). be able to.
The non-filler-containing fluororesin coating composition in the present invention may be added with the above-mentioned additives as necessary.
In the same manner as the primer composition described above, the non-filler-containing fluororesin coating composition is in addition to the fluororesin (E) and the fluororesin (D) used as necessary, and other than these fluororesins. A resin or the like may be added.
The filler-free fluororesin coating composition is preferably a powder coating composed of a fluororesin (E) from the viewpoint of easily increasing the film thickness and improving the corrosion resistance.
The filler-free fluororesin coating composition can be applied using the same method as the primer composition described above.

The use of the fluororesin-containing laminate of the present invention is not particularly limited. For example, the coating material for various electric wires such as heat-resistant enameled wire is used in the point that it has excellent processing deterioration resistance as compared with conventional PAI enameled wire; Parts (paper separation claw, printer guide, gear, bearing), connectors, vernier sockets, IC sockets, electrical parts for oil fields, relays, electromagnetic shielding, relay cases, switches, covers, terminal board buses, etc. Applications: Valve seats, hydraulic seals, backup rings, piston rings, wear bands, vanes, ball bearing retainers, rollers, cams, gears, bearings, labyrinth seals, pump parts, mechanical linkages, bushings, fasteners, spline liners, Bracket, hydraulic piston, chemical pump casing, Mechanical industry-related applications such as lubes, valves, tower packing, coil bobbins, packing, connectors, gaskets, valve seals; thrust washers, seal rings, gears, bearings, tappets, engine parts (pistons, piston rings, valve steers), transmission parts (Spool valve, ball check valve, sealing), rocker arm and other vehicle industry related applications; jet engine parts (bushings, washers, spacers, nuts), power control clutches, door hinge bearings, connectors, tube clamps, brackets, hydraulics Parts, antennas, radomes, frames, fuel system parts, compressor parts, rocket engine parts, wear strips, connector shelves, aerospace applications such as space structures, etc.In addition, there are applications such as iron making machine pin covers, plating equipment parts, nuclear power related parts, ultrasonic transducers, potentiometer shafts, faucet parts and the like.

As a use of the fluorine-containing laminate of the present invention, in addition to the above-mentioned uses, for example, stirring blade, tank inner surface, vessel, tower, centrifuge, pump, valve, piping, heat exchanger, plating jig, tank lorry inner surface, Corrosion resistant applications such as screw conveyors; semiconductor related applications such as semiconductor factory ducts; industrial mold release applications such as OA rolls, OA belts, papermaking rolls, film production calendar rolls, injection molds; rice cookers, pots, hot plates, Home appliances and kitchen related applications such as iron, frying pan, home bakery, pan tray, gas table top plate, pan top plate, pan, pot, etc .; precision mechanism sliding member including various gears, paper roll, calendar roll, mold release parts, Casing, valve, valve, packing, coil bobbin, oil seal, joint, antenna cap, connector Gaskets, valve seals, buried bolts, industrial parts related applications such as built-in nut and the like.

The fluororesin-containing laminate of the present invention can be particularly suitably used as a lining member installed in a hollow metal tube.
The duct of the present invention includes a hollow metal tube and the fluororesin-containing laminate of the present invention lined on the inner surface of the hollow metal tube, the hollow metal tube, the primer layer (1) and the filling The material-containing fluororesin layer (2) is laminated in this order.

Examples of the hollow metal tube include those made of stainless steel, iron, aluminum, brass, and copper.
The inner diameter of the hollow metal may be 10 mm or more, and may be 50 mm or more and 20000 mm or less as long as it is within the above range. Furthermore, if it is in the said range, 100 mm or more may be sufficient and 1000 mm or less may be sufficient.
The outer diameter of the hollow metal may be the same size as the inner diameter of the hollow metal, but the thickness of the hollow metal is preferably 0.5 to 500 mm.
The length of the hollow metal before painting may be 10 mm or more, and may be 50 mm or more and 20000 mm or less as long as it is within the above range. Moreover, the duct of this invention can be made into any length by cut | disconnecting or connecting the said hollow metal after coating.

In the duct of the present invention, the inner surface of the hollow metal tube is subjected to a lining treatment made of the fluororesin-containing laminate of the present invention.
In the duct of the present invention, the fluororesin-containing laminate of the present invention used for the lining treatment preferably includes the filler-free fluororesin layer (3) described above.
On the inner surface of the hollow metal tube, the primer layer (1) and the filler-containing fluororesin layer (2) constituting the fluororesin-containing laminate of the present invention, and a filler-free fluororesin that is laminated as necessary Each layer (3) can have a film thickness in the above-described range.
The lining treatment is not particularly limited and can be performed by a known method. However, the primer layer (1) is preferably laminated by spray coating, and the filler-containing fluororesin layer (2) and, if desired, The filler-free fluororesin layer (3) to be laminated is preferably laminated successively by electrostatic coating.

Although the fluororesin-containing laminate of the present invention does not contain hexavalent chromium serving as a binder component in the primer layer, it has excellent heat-resistant adhesion with the interlayer and the object to be coated, and further has corrosion resistance and chemical resistance. Since it is excellent in properties and easy to coat thick films, it can be suitably used for various applications such as lining materials for industrial members such as ducts and coating materials for various articles.

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 comparative examples.

Production Example 1 (Preparation of primer composition)
10.00 g of 30% N-methyl-2-pyrrolidone solution of polyamideimide resin, tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer [PFA] (trade name: HI-680, manufactured by Hitachi Chemical Co., Ltd., melting point: 305 ° C., average particle size: 25 μm) 6.66 g, polyphenylene sulfide resin [PPS] (average particle size: 25 μm, trade name: Ryton V-1, manufactured by Philips) 0.33 g was added to N-methyl-2-pyrrolidone 13 In addition to a mixed solvent of .80 g and methyl isobutyl ketone 9.20 g, a primer composition was obtained by dissolving and dispersing using a disper (trade name: Three-One Motor, manufactured by Shinto Kagaku Co., Ltd.).

Production Example 2 (Preparation of Filler-Containing Fluororesin Composition)
FEP powder coating (average particle size: 50 μm, melt flow rate: 1 g / 10 min, measured by ASTM D-2116 in this specification) 500 g, titanium oxide (D960, R960) 20 g, di-β-naphthyl -10 g of p-phenylenediamine and 5 g of 2-mercaptobenzimidazole zinc salt were mixed with a Henschel mixer to obtain a filler-containing fluororesin composition.

Example 1
Iron plate (SS400; length 100 mm × width 50 mm × thickness 1.5 mm; average roughness [Ra] using alumina powder (trade name: Tosa Emery # 40, manufactured by Ujiden Chemical Co., Ltd.) with a spraying pressure of 1.0 MPa ] 2 to 3 μm, measured using a surface roughness profile measuring machine Surfcom 470A (manufactured by Tokyo Seimitsu Co., Ltd.) according to JIS B0601, and spray coating the primer composition so that the dry film thickness is 30 μm. And dried at 120 ° C. for 30 minutes.
On the obtained primer layer, electrostatic coating and baking at 350 ° C. were repeated using the filler-containing fluororesin composition to obtain a fluororesin-containing laminate (1) having a total film thickness of 800 μm.

The following tests were performed on the obtained fluororesin-containing laminate (1).
Initial adhesion test On the obtained fluororesin-containing laminate, a test piece with a width of 10 mm was made and conformed to JIS K 6854-1 (1999) using a Tensilon universal testing machine. The peel adhesion strength was measured in the 90 ° direction with respect to the test piece at a pulling speed of 50 mm / min.

Heat resistance test A test piece with a width of 10 mm was placed in an electric furnace at 350 ° C., heated for 50 hours, returned to room temperature, and peeled in a 90 ° direction with respect to the test piece in the same manner as the initial adhesion test. The bond strength was measured.

Heat-resistant water treatment test A test piece with a cut width of 10 mm was immersed in hot water of 90 ° C. or more for 120 hours, then returned to room temperature, and peel-bonded in a 90 ° direction to the test piece in the same manner as the initial adhesion test. Strength was measured.

Surface smoothness According to JIS B0601, Ra value was measured using a surface roughness shape measuring machine (Surfcom 470A, manufactured by Tokyo Seimitsu Co., Ltd.).

Example 2
On the fluororesin layer of the fluororesin-containing laminate (1) obtained from Example 1, electrostatic coating and baking (350 ° C.) were performed using the FEP powder paint used in Production Example 2, and the film thickness A fluororesin-containing laminate (2) having a total of 850 μm was obtained.

Comparative Example 1
Using the FEP powder coating material (average particle size: 50 μm, melt flow rate: 1 g / 10 min) used in Production Example 2 on the primer layer obtained by the same method as in Example 1, electrostatic coating And repeated baking at 350 ° C. for 30 minutes to obtain a laminate having a total film thickness of 800 μm.

Comparative Example 2
The same operation as in Example 1 was performed except that a chromium-free primer (product number: 420-703, manufactured by DuPont) was used as the primer composition.

Comparative Example 3
The same operation as in Example 1 was performed except that a pigment-containing primer (made of polyamideimide, PTFE, FEP, and black pigment. Trade name: EK1909BK, manufactured by Daikin Industries, Ltd.) was used as the primer composition.

In Examples 1 and 2 in which the filler-containing fluororesin layer was laminated on the primer layer, the initial adhesion, the adhesion after the heat test, and the adhesion after the hot water treatment test were all higher than those of Comparative Examples 1 to 3, As for the adhesion, it was found that the initial adhesion was maintained relatively well after both the heat resistance test and the heat resistance water treatment test, and the interlayer adhesion was excellent.
When Example 1 was compared with Comparative Example 1, it was found that the surface smoothness could be adjusted by providing a layer containing a filler on the primer layer (1). By selecting the type and amount of the filler, it is considered that design properties can be obtained depending on the application, such as a matte coating film. Moreover, although the comparative example 1 was excellent in surface smoothness than Example 1, it turned out that adhesive force is weak and cannot endure practically.
Example 2 provided with a non-filler-containing fluororesin layer suppresses a decrease in adhesion due to a heat resistance test and a heat-resistant water treatment test and significantly improves surface smoothness, compared to Example 1 in which this layer is not provided. I found out that

Although the fluororesin-containing laminate of the present invention does not contain hexavalent chromium serving as a binder component in the primer layer, it has excellent heat-resistant adhesion with the interlayer and the object to be coated, and further has corrosion resistance and chemical resistance. Since it is excellent in properties and easy to coat thick films, it can be suitably used for various applications such as lining materials for industrial members such as ducts and coating materials for various articles.

Claims (9)

A fluororesin-containing laminate comprising a primer layer (1) obtained by painting a primer composition, and a filler-containing fluororesin layer (2),
The primer composition has an amide group-containing polymer compound (A) having an amide group or an amide group, and an antioxidant substance (B) capable of suppressing oxidation of the amide group And a coating composition comprising a fluororesin (C),
The amide group-containing polymer (A) is obtained by baking the amide group-containing polymer (a1) having an amide group and an aromatic ring and / or the primer composition. An amide group-containing polymer precursor (a2) that changes to a containing polymer (a1),
The antioxidant substance (B) is 0.1 to 20% by mass of the total of the amide group-containing polymer compound (A) and the antioxidant substance (B),
The said filler containing fluororesin layer (2) consists of a fluororesin (D) and a filler, The fluororesin containing laminated body characterized by the above-mentioned. The fluororesin-containing laminate according to claim 1, wherein the filler constituting the filler-containing fluororesin layer (2) is 0.1 to 30 parts by mass per 100 parts by mass of the solid content of the fluororesin (D). The fluororesin-containing laminate according to claim 1 or 2, wherein the antioxidant substance (B) is polyarylene sulfide. The fluororesin-containing laminate according to claim 1, 2 or 3, wherein the fluororesin (C) and the fluororesin (D) are perfluoro resins. The fluororesin-containing laminate according to claim 1, 2, 3, or 4, wherein the filler-containing fluororesin layer (2) is formed by coating a powder paint comprising the fluororesin (D) and the filler. body. 6. The fluororesin-containing laminate according to claim 1, further comprising a filler-free fluororesin layer (3) comprising substantially no filler and comprising a fluororesin (E). And
The primer layer (1), the filler-containing fluororesin layer (2) and the filler-free fluororesin layer (3) are laminated in this order. The fluororesin-containing laminate according to claim 6, wherein the fluororesin (E) is a perfluoro resin. The fluororesin-containing laminate according to claim 6 or 7, wherein the non-filler-containing fluororesin layer (3) is formed by coating a powder paint made of a fluororesin (E). A duct comprising a hollow metal tube and a fluororesin-containing laminate according to claim 1, 2, 3, 4, 5, 6, 7 or 8, lined on the inner surface of the hollow metal tube,
The hollow metal tube, the primer layer (1), and the filler-containing fluororesin layer (2) are laminated in this order.