JP4243806B2 - Heat-resistant non-adhesive coated steel sheet - Google Patents

Description

  The present invention relates to a heat-resistant, non-adhesive coated steel sheet that is used as a cooking utensil, a sliding member, etc. and has excellent wear resistance, heat resistance, and non-adhesiveness.

When a resin such as a fluororesin is combined with a metal plate, excellent properties such as lubricity, heat resistance, non-adhesiveness, and contamination resistance are imparted, and cooking utensils such as breads, cake baking molds, frying pans, etc. Materials suitable for plates, electronic control jars, gas table tops, and sliding members that require lubricity can be obtained. The defects that tend to be deficient in wrinkle resistance and abrasion resistance derived from a soft resin coating are eliminated by the dispersion of inorganic flakes, making it a material suitable for products that can withstand long-term use (Patent Document 1).
JP2003-25488

Another characteristic required for the resin composite metal plate is corrosion resistance. In particular, cooking utensils that come into contact with various seasonings are used in an acidic corrosive atmosphere, and are subject to corrosion-induced coating film peeling and swelling. Especially in cooking utensils that are exposed to boiling salt water. There is a tendency for coating film peeling and film swelling to be promoted. Coating film peeling and coating film swelling can be suppressed by providing a coating film to which a rust preventive pigment has been added after a chemical conversion treatment is applied to a coating original plate having excellent corrosion resistance.
Chromate treatment has been used for chemical conversion treatment, and Cr-based anti-rust pigments have been used for anti-corrosion pigments. However, if Cr is eluted from a chemical conversion coating or resin coating, it will adversely affect health and the environment. Treatment and non-chromium anticorrosive pigments are beginning to be adopted. However, corrosion resistance comparable to that of chromate coatings and Cr-based anticorrosive pigments is difficult to obtain, and the state of completely eliminating anti-corrosion measures due to chromate treatment and Cr-based anticorrosive pigments has not been achieved.

  The present invention has been devised to solve such problems, and is comparable to the chromate treatment and Cr-based rust preventive pigment by the specified combination of the coating original plate, the chemical conversion coating, the primer layer, and the top coating. An object of the present invention is to provide a heat-resistant, non-adhesive coated steel sheet that imparts corrosion resistance and can utilize the excellent characteristics of a fluororesin layer over a long period of time.

The present invention is a heat-resistant non-adhesive coated steel plate in which a hot-dip aluminized steel plate is used as a coating original plate and a top coating film is formed through a chemical conversion film and a primer layer. As the hot-dip aluminum-plated steel sheet, a plated steel sheet in which a hot-dip aluminum plating layer containing Si: 3 to 15% by mass is formed on the steel sheet surface is used. The molten aluminum plating layer can contain a small amount of Zn, Mg, Ti, Ni, Cu or the like as required. A molten aluminum-plated steel sheet is brought into contact with a non-chromium chemical conversion treatment solution to form a fluoroacid film of 1.0 to 500 mg / m ² in terms of fluorine or total metal, and then phosphoric acid comprising magnesium zinc phosphate A primer layer is formed with a heat-resistant resin paint blended with an anticorrosive pigment, and a top coating is formed with a heat-resistant resin paint blended with a heat-meltable fluororesin.

  The paint for forming the primer layer and the top coating film is based on at least one kind of heat-resistant resin such as polyethersulfone resin, polyphenylsulfide resin, and polyamideimide resin. The primer layer coating is prepared by blending a phosphate-based rust preventive pigment selected from zinc phosphate, magnesium phosphate, and magnesium zinc phosphate into a heat-resistant resin. The coating for the top coating film is prepared by blending a polymer or copolymer of tetrafluoroethylene, hexafluoroethylene, perfluoroalkyl vinyl ether, or chlorotrifluoroethylene with a heat resistant resin. The top coating film formed from the heat-resistant resin paint blended with the heat-melting fluororesin particles has the coating film surface covered with a thin film formed from the heat-melting fluororesin particles.

The fluoroacid film is a film made of fluorine and a metal component of fluoroacid in which a metal component of fluoroacid is deposited on the surface of the plating layer which has been etched and activated with fluoroacid dissolved in water. Fluoroacids include H ₂ TiF ₆ , H ₂ ZrF ₆ , H ₂ HfF ₆ , H ₂ SiF ₆ , H ₂ GeF ₆ , H ₂ SnF ₆ , HBF ₄ and so on. Therefore, the reaction product AlF ₃ of Al and fluorine in the molten aluminum plating layer is also included in the fluoroacid film. Since the fluoroacid film is formed by reaction with the molten aluminum plating layer, the film adhesion is excellent, and since it is dense, the environment blocking ability is also excellent.

  Phosphoric anticorrosive pigments such as zinc phosphate, magnesium phosphate, and magnesium zinc phosphate contained in the primer layer react with the metal component of the fluoroacid contained in the chemical film, and the chemical film / primer layer An insoluble compound layer is formed at the interface. The insoluble compound layer, together with the dense chemical conversion film, enhances the environmental barrier ability and prevents corrosive components that have permeated the primer layer from reaching the plating layer. Since the primer layer itself is based on a heat-resistant resin such as a polyethersulfone resin, a polyphenylsulfide resin, or a polyamideimide resin, it sufficiently withstands continuous exposure at about 300 ° C.

  The top coating film laminated on the primer layer is formed from a paint in which heat-meltable fluororesin particles are blended with a heat-resistant resin such as polyethersulfone resin, polyphenylsulfide resin, or polyamideimide resin. The heat-meltable fluororesin softens and melts when the heat-resistant resin paint is baked, and becomes a thin film and floats on the surface of the top coating film. Since the top coating film is covered with a fluororesin thin film, the excellent lubricity, heat resistance, non-adhesiveness, and contamination resistance inherent in the fluororesin are exhibited.

[Original coating and pretreatment]
As the coating original plate, a plated steel plate in which a molten aluminum plating layer containing Si: 3 to 15% by mass is formed on the steel plate surface is used. Si is an effective component for suppressing the formation and growth of an Fe—Al—Si alloy layer that is likely to occur at the interface between the base steel and the molten aluminum plating layer and ensuring the workability of the Al-plated steel sheet. The suppression effect of the Fe—Al—Si alloy layer becomes significant when the Si content is 3% by mass or more. However, when an excessive amount of Si exceeding 15% by mass is contained, the primary crystal is formed in the solidification cooling process of the molten aluminum plating layer. Si crystallizes, and the adhesiveness of the hot-dip aluminum plating layer and the workability of the Al-plated steel sheet tend to deteriorate. The molten aluminum plating layer can also contain a small amount of Zn, Mg, Ti, Ni, Cu or the like as required.
The coated original sheet is degreased to improve the coating film adhesion. The degreasing method uses a weak alkaline or neutral degreasing solution according to a conventional method without any particular restrictions, and cleans the surface of the Al-plated steel sheet by dipping, spraying, or the like. Next, when pickling, phosphate treatment, or the like is performed as necessary, the wettability of the plating layer surface is improved.

[Chemical conversion treatment]
The surface-cleaned coating original plate is subjected to chemical conversion treatment prior to coating, and a chemical conversion film effective for improving coating film adhesion is formed on the surface of the plating layer. For the chemical conversion treatment, a chemical conversion treatment solution using non-chromium fluoroacid is used. After the chemical conversion treatment solution applied to the coating original plate by a roll coater, curtain flow coater, dipping method, or the like is squeezed with a ringer roll or the like, it is washed with water. Without drying, the fluoroacid film is formed on the surface of the plating layer by drying at 80 to 200 ° C.
Fluoroacids include H ₂ TiF ₆ , H ₂ ZrF ₆ , H ₂ HfF ₆ , H ₂ SiF ₆ , H ₂ GeF ₆ , F ₂ SnF ₆ , HBF _{4 and the} like, and H ₂ TiF ₆ is the most excellent. Shows rust prevention effect. Fluoroacids can be used alone or as a mixture of two or more.

The fluoroacid aqueous solution is a fluoride system having a strong etching property, and the Al—Si eutectic part contained in the molten aluminum plating layer, which is difficult to activate with a general inorganic acid, is also activated. In addition, the fluorine component reacts with the Al content of the molten aluminum plating layer, and the hardly soluble reaction product AlF ₃ is contained in the fluoroacid coating near the plating layer. Since Furuoroashi head film is formed by the reaction of molten aluminum plating layer, showed the paint adhesion comparable to chromate film formed by the conventional chromate treatment, chemical conversion excellent in environmental shielding performance since dense It becomes a film.

  The metal component of the fluoroacid coating reacts with the hydroxyl group of the primer coating resin to improve the adhesion of the undercoat coating. Furthermore, phosphoric acid ions are eluted from the phosphoric acid-based anticorrosive pigment in the undercoat, reacting with Al in the base and molten aluminum plating layer, and reprecipitated as an insoluble phosphate, resulting in defects in the fluoroacid film. Department is also self-healing. In addition, the atmosphere is slightly acidified when phosphate ions are dissociated from the phosphate-based anticorrosive pigment in the primer coating, which accelerates the hydrolysis of titanium fluoride and, consequently, the formation of poorly soluble titanium oxide or hydroxide. And the conversion coating / primer layer interface is reinforced with insoluble compounds. The insoluble compound layer, together with the dense chemical conversion film, enhances the environmental barrier ability, and prevents corrosive components that have permeated through the primer layer from reaching the plating layer of the coating original plate.

If necessary, an aqueous solution of aminomethyl-substituted polyvinylphenol or the like dissolved in propoxypropanol as an organic resin can be added to the fluoroacid aqueous solution. The organic resin is combined with the titanium compound and fluoride in the treatment liquid to form a sparingly soluble organic-inorganic composite film on the surface of the molten aluminum plating layer.
Assuming applications in high-temperature environments, the organic resin component deteriorates in molten Zn or molten Zn-Al-plated steel sheets with a composite coating containing many organic resin components, and moisture and corrosive components enter the fluoroacid coating. There is a concern that the ZnF ₂ is dissolved and the corrosion resistance is deteriorated. However, since a hot-dip aluminum-plated steel sheet is used for the coating original sheet, the chemical conversion film does not contain a water-soluble reaction product. Even if the organic resin deteriorates due to heat, the phosphate ion elutes from the phosphoric acid-based anticorrosive pigment in the undercoat and reacts with Al in the base plating layer to cause re-precipitation of insoluble phosphate. Is self-healing, thus maintaining excellent environmental barrier.

The chemical conversion film is formed with a thickness effective for preventing corrosion of the molten aluminum plating layer and improving coating film adhesion. The coating amount of the chemical conversion film is adjusted so as to be 1 to 500 mg / m ^{2 in} terms of the fluorine conversion deposition amount and / or the total deposition amount of Ti, Zr, Hf, Si, Ge, Sn, and B. Adhesion amount: Less than 1 mg / m ² chemical conversion film does not exhibit sufficient film adhesion, heat resistance, and corrosion resistance. Conversely, an adhesion amount exceeding 500 mg / m ² not only saturates the rust prevention effect, The coating film adhesion tends to decrease.

[Primer layer]
After the chemical conversion treatment, a transparent or colored heat-resistant paint is applied to the Al-plated steel sheet, and an undercoat film (primer layer) is formed by drying and baking. As a heat-resistant paint for undercoating, non-chromium-based anti-corrosion is used to obtain even better corrosion resistance, such as the prevention of defects such as blisters and rust starting from the coating end defects of coated metal plates and during processing or construction. At least one heat-resistant resin of polyethersulfone resin, polyphenylsulfide resin, and polyamideimide resin blended with a rust pigment can be used.

  As a non-chromium rust preventive pigment, it reacts with Al in the base plating layer to precipitate insoluble phosphate, thereby self-repairing the defective part of the fluoroacid film, and further adding an insoluble compound at the interface of the chemical conversion film / primer layer. The resulting phosphoric acid anticorrosive pigment is used. Examples of phosphoric acid-based rust preventive pigments include zinc phosphate, magnesium phosphate, and magnesium zinc phosphate. Magnesium zinc phosphate that stably elutes phosphate ions in any acidic, neutral, or alkaline environment. Is preferred.

The phosphoric acid rust preventive pigment blended in the undercoat paint preferably has an average particle diameter in the range of 0.1 to 10 μm. If the particle size is too small, the anticorrosive pigment tends to aggregate when dispersed in the paint. Conversely, if the particle size is too large, the original properties of the coating are impaired, and the surface of the coating is not only smooth, but the surface of the coating is skin-like. The appearance will deteriorate significantly.
The phosphoric acid-based rust preventive pigment is preferably blended at a ratio of 5 to 150 parts by mass with respect to 100 parts by mass of the resin solid content. The effect of improving the corrosion resistance of the coating film by the phosphoric acid-based anticorrosive pigment becomes remarkable when the amount is 5 parts by mass or more. However, even if an excessive amount of phosphoric acid-based anticorrosive pigment exceeding 150 parts by mass is blended, an effect commensurate with the increase cannot be obtained, and the workability and adhesion of the coating film are deteriorated.

  The primer layer may be transparent, but may be colored to an appropriate color tone with titanium oxide, carbon black, chromium oxide, iron oxide or the like according to needs. In addition, glass flakes, barium sulfate flakes, graphite flakes, synthetic mica flakes, synthetic alumina flakes, silica flakes and other flaky inorganic additives, potassium titanate fibers, wollastonite fibers, silicon carbide weaves, alumina fibers, alumina silicate fibers When inorganic fibers such as silica fiber, rock wool, slag wool, glass fiber, and carbon fiber are blended, the coating film hardness and wear resistance are improved.

The primer paint prepared to a predetermined composition is applied to a hot-dip aluminized steel sheet by roll coating, flow coating, curtain flow, spraying, dipping, etc., which are commonly used in the production of pre-coated steel sheets, and an ultimate sheet temperature of 300 to 400 ° C. X It is baked in 30 to 180 seconds.
The amount of the primer coating applied is adjusted so that a primer layer having a dry film thickness of 0.5 to 30 μm is formed after baking. In the case of forming a transparent primer coating containing only a small amount of phosphoric acid-based anticorrosive pigment, effects such as corrosion resistance and coating adhesion due to the formation of the primer coating are manifested when the dry film thickness is 0.5 μm or more. In the case of a colored coating film, a dry film thickness of 3 μm or more is preferable in order to conceal the surface of the molten aluminum plating layer. In any case, in the case of a thick primer layer having a dry film thickness of more than 30 μm, not only does the surface of the coating film become crusted and the appearance deteriorates, but cracks are likely to occur during baking.

[Top coating film]
A heat-resistant non-adhesive paint is applied on the primer layer, and a heat-resistant non-adhesive top coating is formed by drying and baking. The heat-resistant non-adhesive paint is prepared by blending a heat-meltable fluororesin having an average particle size of 1 μm or less with at least one heat-resistant resin of polyethersulfone resin, polyphenylsulfide resin, and polyamideimide resin. The compounding quantity of a heat- meltable fluororesin is selected in the range of 10-200 mass parts with respect to 100 mass parts of solid content of a heat resistant resin coating material.

  As the heat-meltable fluororesin, a fluororesin having a melting point of 270 ° C. or higher is preferable from the viewpoint of heat resistance and non-adhesiveness, and at least one monomer such as tetrafluoroethylene, hexafluoroethylene, perfluoroalkyl vinyl ether, chlorotrifluoroethylene, and the like. A polymer or copolymer consisting of can be used. In particular, since non-adhesion persists, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymerization resistance (PFA), tetrafluoroethylene-perfluoroalkyl vinyl ether-hexafluoropropylene copolymer (FEP) are preferable, and heat resistance is further improved. PFA is optimal from the viewpoint.

The heat-meltable fluororesin is preferably a powder having an average particle size of 1 μm or less in order to impart dispersibility to the coating resin and non-adhesiveness and heat resistance excellent in the coating film. The heat-meltable fluororesin having an average particle size of 1 μm or less is easily melted when the coating film is baked to form a fluororesin-like thin film on the surface of the top coating film. For forming a thin film, a heat-meltable fluororesin having an average particle size of 0.5 μm or less is more preferable.
A heat-meltable fluororesin is mix | blended with a heat-resistant non-adhesive coating material in the ratio of 10-200 mass parts. The non-stickiness persistence due to the blending of the heat-meltable fluororesin becomes prominent at a blending ratio of 10 parts by mass or more, but excessive blending exceeding 200 parts by weight may cause the adhesiveness of the top coating to the primer layer to decrease. Become. In order to balance non-adhesive durability and coating film adhesion, it is preferable to select the blending amount of the heat-meltable fluororesin in the range of 50 to 150 parts by mass, and further 80 to 120 parts by mass.

  The top coating can be transparent, but can be colored to an appropriate color with titanium oxide, carbon black, chromium oxide, iron oxide or the like according to needs. Like the primer layer, glass flakes, barium sulfate flakes, graphite flakes, synthetic mica flakes, synthetic alumina flakes, silica flakes and other inorganic inorganic additives, potassium titanate fibers, wollastonite fibers, silicon carbide fibers, alumina fibers, When inorganic trade fibers such as alumina silicate fiber, silica fiber, lock wool, slag wool, glass fiber and carbon fiber are blended, the coating film hardness and wear resistance are improved.

  The heat-resistant non-adhesive paint prepared to a predetermined composition is applied to a hot-dip aluminized steel sheet by roll coating, flow coating, curtain flow, spraying, dipping, etc., which are commonly used in the production of pre-coated steel sheets. Bake at 450 ° C. for 60 to 180 seconds. The application amount of the heat-resistant non-adhesive paint is adjusted so that a heat-resistant non-adhesive coating film (top coating film) having a dry film thickness of 5 to 40 μm is formed after baking. If the dry film thickness is less than 5 μm, the non-stickiness persistence will not be fully expressed. Conversely, if the film thickness is greater than 40 μm, the coating surface will be crumpled and the appearance will be deteriorated. It becomes easy. From the viewpoint of workability, a top coating film having a thickness of 5 to 20 μm is preferable.

As described above, when a plated steel sheet having a molten aluminum plating layer formed thereon is used as a coating original plate and a coating film is formed through a fluoroacid film, it is difficult to be a reaction product of Al content and fluorine of the molten aluminum plating layer. Because soluble AlF ₃ is taken in and a fluoroacid film is formed by reaction with the molten aluminum plating layer, the excellent environmental barrier properties of the molten aluminum plating layer and the dense fluoroacid film are utilized, and The adhesion of the fluoroacid film is also improved. Even if a defect occurs in the film, the phosphate ions eluted from the phosphate-based rust preventive pigment blended in the primer layer become an insoluble phosphate and reprecipitate to self-repair the film defect. In addition, since the atmosphere is slightly acidified when the phosphate ions are dissociated, the hydrolysis of titanium fluoride, and hence the generation of hardly soluble titanium oxide or hydroxide, is promoted. As a result, an insoluble compound is formed at the chemical film / primer layer interface, and the environmental barrier is improved in combination with the dense chemical film, and the corrosive components that have permeated the primer layer reach the plating layer of the coating original sheet. And interfacial corrosion is prevented. Accordingly, a non-chromium heat-resistant non-adhesive coated steel sheet exhibiting excellent corrosion resistance is obtained in addition to the flat portion, as well as the cut end face and the coating wrinkled portion.
Hot-dip non-adhesive coated hot-dip aluminized steel sheet is an environment-friendly heat-resistant non-adhesive coated steel sheet that uses cooking utensils such as frying pans, gas table top plates, hot plates, pan-bakers, oil pots, and microwave oven wall materials. At first, it is also used as a sliding member that requires household appliances, kitchen appliances, heat resistance, non-adhesiveness, and lubricity.

Thickness: 0.5 mm, per side coating weight: a molten Al-9% Si plated steel sheet 40 g / m ² was used to paint the original plate, degreasing, water washing, surface conditioning, washed with water, and surface cleaning and drying steps . As a comparative material, a Zn—Al alloy-plated steel sheet having a thickness of 0.5 mm and a coating amount per side of 60 g / m ² was prepared, and the surface was similarly cleaned.
The fluoroacid treatment liquid shown in Table 1 was applied to the coating original plate after the surface was cleaned with a bar coater and dried at 100 ° C. to form a fluoroacid film. The amount of treatment liquid applied was adjusted by the count of the bar coater. Moreover, the density | concentration of the aminomethyl substituted polyvinylphenol was changed in the range of 0-20 mass parts, and the resin amount in a fluoroacid film | membrane was adjusted. As a comparative material, a commercially available chromate treatment solution (ZM-3387: manufactured by Nihon Parkerizing Co., Ltd.) was applied to the coating original plate, and similarly heated and dried at 100 ° C.

  A polyethersulfone resin paint (Table 2) containing a rust preventive pigment and colored black with carbon black was applied to the coated raw plate that had been subjected to chemical conversion treatment, and dried and baked at 360 ° C. for 90 seconds to obtain a dry film thickness of 5 μm. A primer layer was formed.

Then, carbon black, a polyethersulfone resin colored black metallic aluminum flake and base over scan, the average particle diameter as a melt processible fluoropolymer: 0.2 [mu] m of tetrafluoroethylene - perfluoroalkyl vinyl ether copolymer 100 The heat-resistant non-adhesive coating material prepared by blending by mass% was applied, and a heat-resistant non-adhesive coating film (top coating film) having a dry film thickness of 10 μm was formed by drying and baking at 400 ° C. for 120 seconds.
A test piece of 70 mm × 150 mm was cut out from each manufactured heat-resistant non-adhesive coated steel plate, heat-treated at 300 ° C. × 100 hours, then cross-cut into a flat portion with a cutter knife, and subjected to the next test. Test numbers 2 and 3 are reference examples.

[Salt spray test]
In accordance with JISZ2371, a 5% NaCl aqueous solution at 35 ° C. was sprayed. After spraying the salt water for a predetermined time, the coating film swelling (edge cleave) generated on the cut end face and the cross cut portion was measured. The coating film width from the cut end face and the cross-cut portion is 0.5 mm or less, ５〜, 0.5 to 1.0 mm is ○, 1.0 to 2.0 mm is △, and 2.0 mm or more is ×. The blister property was evaluated.
[Boiling salt water test]
After immersing the test piece in a boiled 5% NaCl aqueous solution for a predetermined time, the cut end face and the crosscut part of the test piece were observed, and the occurrence state of coating film swelling (edge creep) was investigated. The survey results were judged according to the same criteria as the salt spray test, and the anti-skin film resistance was evaluated.

  As seen in the survey results in Table 3, the heat-resistant non-adhesive coated steel sheet (test numbers 1 to 5) according to the present invention forms a primer coating containing a non-chromium chemical conversion treatment and a non-chromium anticorrosive pigment. Nevertheless, both the cut end face and the cross cut part showed excellent corrosion resistance in both the salt spray test film and the boiling salt water test. Boiled salt-water resistant performance is superior to conventional heat-resistant non-stick coated steel sheets containing chromium compounds (Test Nos. 6 and 12), and because they do not contain chromium compounds, they must be heat-resistant non-stick coated steel sheets that do not adversely affect the environment. Was confirmed.

  On the other hand, the heat-resistant non-adhesive coated steel sheet (Test No. 7) lacking the titanium compound and fluoride lacked the environmental barrier property of the chemical conversion film and was extremely inferior in corrosion resistance. In Test Nos. 8 and 9 in which a non-chromium rust preventive pigment that does not elute phosphate ions is blended in the primer layer, since there is no phosphate ion elution, self-repairing action cannot be expected on the chemical conversion film of the crosscut part, The boiling salt water was extremely inferior. In test number 10 in which a primer layer containing a phosphoric acid-based anticorrosive pigment was provided on a coating original plate whose plating type was changed to Zn-55% Al, and in test number 11 in which a conventional chromium-based anticorrosive pigment was blended in the primer layer, a chemical conversion film The organic resin inside deteriorated due to the heat treatment, and the salt spray test showed good results, but in the boiling salt water test, significant coating swelling occurred.

  As explained above, the use of a specified combination of a coating original plate, a chemical conversion coating, a primer layer, and a top coating is sufficient, even without the use of chromate treatment and Cr-based anticorrosive pigments that have a large environmental impact. Heat-resistant non-adhesive coated steel sheet exhibiting excellent corrosion resistance is obtained. The top coating is covered with a fluororesin thin film excellent in lubricity, heat resistance, non-adhesiveness, and contamination resistance, and also has excellent corrosion resistance, so that a beautiful surface is maintained over a long period of time. Used as a material suitable for a moving member or the like.

Claims (3)

Si: on a molten aluminum-plated steel sheet on which a molten aluminum plating layer containing 3 to 15% by mass is formed, on a fluorine equivalent adhesion amount and / or on a total metal adhesion amount: 1 to 500 mg / m ² of a fluoroacid film, a heat-resistant resin Primer layer formed from paint containing phosphoric acid-based anticorrosive pigment composed of magnesium zinc phosphate, formed from paint containing heat-melting fluororesin particles in heat-resistant resin, and produced from heat-melting fluororesin particles A heat-resistant non-adhesive coated steel sheet, in which a top coating whose coating surface is covered with a thin film is sequentially laminated.   The heat-resistant non-adhesive coated steel sheet according to claim 1, wherein the primer layer and the paint for forming the top coating film are based on at least one heat-resistant resin such as a polyethersulfone resin, a polyphenylsulfide resin, and a polyamideimide resin.   The heat-resistant non-stick coated steel sheet according to claim 1, wherein the heat-meltable fluororesin is a polymer or copolymer comprising at least one of tetrafluoroethylene, hexafluoroethylene, perfluoroalkyl vinyl ether, and chlorotrifluoroethylene.