KR100346796B1 - fluorin resin coated product and process for producing the same - Google Patents

Abstract

It is an object of the present invention to provide a fluorine resin coating having excellent abrasion resistance, scratch resistance, corrosion resistance, blister resistance and the like and a method for producing the same, wherein one or more fluorine resin layers are provided on the substrate. In the coated fluororesin coating, the outermost layer is a PFA containing tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA) having a melt flow rate of 0.2 to 10 g / 10 min as specified in ASTM-D-3307. Provided is a fluororesin coating and a method for producing the same, characterized in that the PFA layer has a thickness of 10 to 90 µm and is made of PFA contained in a total amount of 20 to 100% by weight.

Description

Fluorine resin coating and its manufacturing method {fluorin resin coated product and process for producing the same}

TECHNICAL FIELD The present invention relates to a fluorine resin coating and a method for producing the same, and more particularly, to a fluorine resin coating having excellent abrasion resistance, scratch resistance, corrosion resistance, blister resistance, and the like. Moreover, this invention relates to the fluorine resin material suitable for manufacturing the fluororesin coating material which is excellent in the said various characteristic.

Conventionally, since the fluorine resin coating which coated the fluorine resin on the base materials, such as a metal base, has a non-stick surface, cooking utensils, such as a pot, a pot, a frying pan, and a jar cooker internal pot; Home appliance cooking appliances such as hot plates, grill pans, auto bakeries and rice cakes; As an oil pot etc., it is applied to a wide range of fields (Japanese Unexamined-Japanese-Patent No. 60-234618, 7-55182). As the fluororesin, polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), etc. which are excellent in heat resistance are generally used.

Fluorine resin coatings are usually produced by coating a fluorine resin on a substrate, baking, and forming a fluorine resin film. In the case of forming a fluorine resin coating into a container shape such as a pot, a pot, a frying pan, or a self-contained inner pot, a fluorine resin coating is prepared using a metal substrate as a base material, and punched into a predetermined shape such as a disc shape if necessary. After processing, it is molded into a desired shape by press working or the like. The fluorine resin coating may be produced by using a metal substrate punched into a predetermined shape such as a disc in advance. The fluororesin layer is formed of one layer or two or more layers. The fluororesin coating has a non-tacky, heat resistant, and corrosion resistant surface, and is suitable for the field of cooking utensils, especially since there is no stickiness of the cooked food.

By the way, the conventional fluorine resin coating has a problem that abrasion resistance and abrasion resistance are not necessarily enough, and it is easy to abrasion or a wound during repeated use. The reason for this is presumably due to insufficient mechanical strength and stress crack resistance of the fluororesin coating film. Conventionally, as a fluororesin, from the viewpoint of processability to a coating film, PTFE having a relatively high molecular weight is applied as a fine particle dispersion, or PFA having a relatively low molecular weight is used as a dry electrostatic powder coating having a relatively large particle diameter. Was doing. In order to improve mechanical strength, stress crack resistance, etc., it is conceivable to further increase the molecular weight of the fluorine resin to be used, but ultra high molecular weight PTFE and high molecular weight PFA may form a uniform and smooth coating film by coating. Very difficult.

An object of the present invention is to provide a fluorine resin coating having excellent abrasion resistance, scratch resistance, corrosion resistance, blister resistance, and a method for producing the same.

Another object of the present invention is to provide a fluorine resin which can form a fluorine resin film excellent in such various characteristics.

The present inventors have diligently studied to overcome the problems of the prior art, and as a result, high molecular weight tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA) having a low melt flow rate (MFR) Even if used, by combining PFA particles having an average particle diameter of 5 to 40 µm (larger particle diameter) and PFA particles having an average particle diameter of 0.1 to 0.5 µm (small particle diameter), a coating film having excellent practicality can be easily formed. It discovered that the coating film excellent in mechanical strength and stress crack resistance can be formed thereby. Both high molecular weight PFA particles can be used as the PFA particles having a large particle diameter and the PFA particles having a small particle diameter, but the low molecular weight PFA particles having a large MFR can be used as the PFA particles having a small particle diameter. In addition, by adopting the powder coating method and selecting the average particle diameter, it is possible to form a practical coating film even in a high molecular weight PFA alone.

The fluorine resin coating material for forming the fluorine resin film may be a powder composed of PFA particles having a large particle diameter, but a dispersion form in which PFA particles having a large particle diameter and PFA particles having a small particle diameter are dispersed in a liquid medium. Fluorine resin is particularly preferred because of its excellent stability and coating film formation as a coating and at the same time only a smoothing effect. By forming such a PFA coating film on the substrate directly or via at least one fluorine resin layer as the outermost layer, abrasion resistance and scratch resistance are remarkably improved, and a fluororesin coating having good corrosion resistance and blister resistance can be obtained. .

Moreover, abrasion resistance and flaw resistance can be improved by forming at least 3 fluorine resin layers on a base material, and arrange | positioning the fluorine resin layer which contains additives, such as a pigment and a filler, in a specific ratio in an intermediate | middle layer. In addition, by forming the intermediate layer into a pattern such as a pattern, a scale, a letter, or the like, designability, indicating functionality, and the like can be imparted to the fluorine resin coating. The present invention has been completed based on these findings.

According to the present invention, in a fluorine resin coating coated with one or two or more layers of fluorine resin layers on a substrate, the outermost layer is a tetrafluoride having 0.2 to 10 g / 10 minutes of a melt fluoride specified in ASTM-D-3307. Provided is a fluororesin coating comprising a fluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA) comprising a PFA layer having a thickness of 10 to 90 탆 made of PFA containing 20 to 100% by weight in the total amount of PFA. do.

Further, according to the present invention, in the method for producing a fluorine resin coating wherein one layer or two or more layers of fluorine resin layers are coated on a base material, directly or at least one layer of fluorine resin layer on the base material, ASTM-D- PFA having a melt flow rate of 0.2 to 10 g / 10 minutes specified in 3307 is coated with a PFA containing PFA containing 20 to 100% by weight in the total amount of PFA. Provided is a method for producing a fluororesin coating, which forms an outermost layer composed of layers.

Further, according to the present invention, PFA particles having an average particle diameter of 5 to 40 µm and a melt florate specified in ASTM-D-3307 of 0.2 to 10 g / 10 minutes and an average particle diameter of 0.1 to 0.5 µm are ASTM-D-3307. Provided is a fluororesin comprising a PFA particle having a melt flow rate of 0.2 to 40 g / 10 minutes as defined in the above, dispersed in a liquid medium in a weight ratio of 20:80 to 80:20.

Further, according to the present invention, in a fluorine resin coating having a fluorine resin layer coated on a base material,

(1) The fluorine resin coating layer is formed of three or more layers of fluorine resin layers composed of a base coat layer in contact with a substrate, at least one intermediate layer, and an outermost layer, and

(2) At least one intermediate layer is formed of a fluororesin composition containing at least one additive selected from the group consisting of organic pigments, inorganic pigments, organic fillers and inorganic fillers in a proportion of 0.5 to 10% by weight.

A fluorine resin coating is provided, which is characterized by the above-mentioned.

The fluorine resin coating of the present invention is a fluorine resin coating wherein one or two or more layers of fluorine resin layers are coated on a base material. As a base material, various metal base materials, such as aluminum base materials, such as aluminum and an aluminum alloy, magnetic or nonmagnetic stainless base materials, and these composite base materials, such as aluminum-SUS, can be used. Moreover, as a base material, a ceramic base material, a glass base material, etc. can also be used. Among these substrates, aluminum-based substrates are preferred for the use of cookware because of their good thermal conductivity and molding processability.

In the fluorine resin coating of the present invention, when the outermost layer is a PFA layer made of PFA containing PFA having a MFR specified in ASTM-D-3307 of 0.2 to 10 g / 10 minutes at a ratio of 20 to 100% by weight, Although a pigment and a filler may be added to PFA, it is preferable that it is only PFA from a viewpoint of abrasion resistance, scratch resistance, coating film formation property, etc. PFA whose MFR used in this invention is 0.2-10 g / 10min is high molecular weight PFA. If the MFR is less than 0.2 g / 10 min, the coating workability deteriorates, making it difficult to form a uniform and smooth coating film. When MFR exceeds 10 g / 10 minutes, the improvement effect of abrasion resistance and abrasion resistance is small, there is no big difference with a conventional product, and sufficient durability cannot be obtained. MFR becomes like this. Preferably it is 0.5-5 g / 10min, More preferably, it is 1-4 g / 10min.

By the way, PFA conventionally used in the technical field of a fluororesin coating has a relatively low molecular weight whose MFR is more than 10g / 10min and about 40g / 10min or less. For example, PFA (trade name MP102) made by Mitsui Dupont Phloro Chemical Co., Ltd., Japan, has an MFR of 13 g / 10 minutes, a melt viscosity of 4 × 10 ⁴ Poise at 380 ° C., and an estimated molecular weight of about 500,000. The PFA (trade name MP10) manufactured by Mitsui DuPont Floro Chemical Company is MFR of 16, a melt viscosity of 4 × 10 ⁴ Poise at 380 ° C. equivalent to MP102, and a molecular weight of approximately 500,000. The PFA of the molecular sieve of the same level is marketed also by the Japanese diking industry company and the Japan Asahi Choza company, and is provided for practical use in this technical field. These PFAs are supplied as a spherical or pulverized release powder or as a dispersion. In the dispersion, PFA, which is estimated to have a molecular weight of about 200,000, is commercially available from Daikin Industries Co., Ltd., and has an MFR of 16 to 35 and a melt viscosity of 1.5 × 10 ⁴ Poise at 380 ° C. However, if these PFAs were used, the coating workability was good, but the wear resistance of the obtained fluororesin coating was insufficient.

On the other hand, in this invention, high molecular weight PFA whose MFR is 0.2-10 g / 10min is used by specific ratio. As such high molecular weight PFA, a commercial item can be used suitably. As a commercial item, the PFA (brand name MP103) manufactured and sold by the DuPont company is mentioned, for example. This MP103 has a small MFR of about 2, and has a very high melt viscosity of 3 × 10 ⁵ Poise at 380 ° C., which makes machining difficult. Therefore, such high molecular weight PFA was difficult to use for coating application to kitchen cooking appliances, such as an internal pot half pot, a pot, a pot, and a frying pan. On the other hand, this PFA is considered to have a molecular weight of about 900,000 or more, and is excellent in mechanical strength and stress crack resistance. Therefore, if it can be applied to the technical field of fluorocarbon resin coating, it has excellent wear durability and resistance to scratches. You can expect to get a coating. The present inventors produced the test piece by compression molding using such a high molecular weight PFA, and it was confirmed that more than twice the wear durability of the conventional PFA molded product is obtained.

However, high molecular weight PFAs having such a low MFR are difficult to form a uniform and uniform coating film without coating defects, even if coated or powder coated as a dispersion coating in which the particles are dispersed in a liquid medium. Do. As a method of solving this problem, for example, a method of increasing the average particle diameter of the high molecular weight PFA and coating the powder can be considered. Further, the inventors conducted further studies, and as a result, the PFA particles having an average particle diameter of 5 to 40 µm and an MFR of 0.2 to 10 g / 10 minutes, and PFA particles having an average particle diameter of 0.1 to 0.5 µm and an MFR of 0.2 to 40 g / 10 minutes. By using the fluorine resin material containing 20: 80-80: 20 by weight ratio, it discovered that the processability is favorable, the coating film without a coating-film defect can be formed, and it is easy to smooth this coating film. As small PFA particles having an average particle diameter of 0.1 to 0.5 µm, high molecular weight PFA particles having an MFR of 0.2 to 10 g / 10 minutes may be used, but low molecular weight PFA particles having an MFR of more than 10 g / 10 minutes and 40 g / 10 minutes or less. Preference is given to using. When the blending ratio of PFA particles having a large particle size of 5 to 40 µm in average particle size is too small, the coating film formability is inferior, and when too large, stability is reduced when a wet coating (dispersion) is used. The blending ratio of the large particle diameter PFA particles and the small particle diameter PFA particles is preferably 50:50 to 80:20.

The fluorine resin coating material containing the PFA particles used in the present invention may be a powder coating material, but the particle spacing of the coating material may be used as a dispersion (wet paint) in which the two kinds of PFA particles are dispersed in a liquid medium. Since it is easy to be smooth and smoothing, it is preferable. In addition, either PFA particles having a large particle diameter or PFA particles having a small particle diameter may be high molecular weight PFA particles. Since it becomes favorable and it becomes easy to suppress generation | occurrence | production of a coating film defect, it is preferable. The ratio of MFR to the total PFA particles of the small high molecular weight PFA particles is 20 to 100% by weight, but from the viewpoint of balancing workability and various physical properties, preferably 20 to 80% by weight, more preferably 50 to 80 It is preferable to set it as weight%. By setting this ratio to 20% by weight or more, the wear resistance of the coating film can be remarkably improved.

The fluororesin containing the PFA particles can be coated by, for example, powder coating, coating of dispersion, spraying, flow coating, screen coating or other printing method, spin coating, roll coating or the like. Among these coating methods, the spray coating of the dispersion is preferable because there is no coating film defect and an easy to obtain smooth coating film is obtained.

When forming an outermost layer by a PFA coating film (PFA layer), it is necessary to make the film thickness into the range of 10-90 micrometers. Fluoropolymer coatings are required to have corrosion resistance and blister resistance (blister durability) in addition to wear resistance (wear resistance) as practically necessary characteristics. Corrosion resistance is the durability which withstands corrosion of the metal of a base material by the salt or organic substance which invades from the minute defect of a coating film, etc. when food or the like is cooked. Blister durability is a performance which endures peeling and swelling called a blister between a coating film, a coating film, and a base material in actual use which repeats cooking. It is presumed that blisters occur because the moisture contained in the coating film, between the coating film, the coating film and the base material escapes as a gas during rapid heating such as cooking, because it pushes the coating film beyond the adhesive force. As a result of the experiment, it was found that when the average thickness of the outermost PFA layer exceeds 90 µm, the blister occurrence frequency increases. In order to increase abrasion durability, the thicker the film thickness of the PFA layer is, the better, but from the viewpoint of blister durability, the thinner side is preferable. When the film thickness of a PFA layer is too small, coating film defects, such as a pinhole penetrating a coating film, will likely arise, and corrosion resistance will fall. Therefore, it is preferable to balance the blister durability and the corrosion resistance, and to set the outermost layer to have a thickness of 10 to 90 m or 15 to 60 m.

The fluororesin coating of the present invention has PFA particles having an average particle diameter of 5 to 40 µm and an MFR of 0.2 to 10 g / 10 minutes and an average particle diameter of 0.1 to 0.5 directly or on at least one layer of fluorine resin layer on the substrate. It can manufacture by apply | coating and baking fluorine resin material containing PFA particle | grains with a micrometer and MFR of 0.2-40 g / 10min by weight ratio 20: 80-80: 20. By this manufacturing method, a coating film (PFA layer) made of PFA containing PFA having an MFR of 0.2 to 10 g / 10 minutes in a proportion of 20 to 100% by weight in the total amount of PFA is formed. The thickness of the PFA layer of an outermost layer shall be 10-90 micrometers. Baking conditions can be suitably determined according to the usual method of forming a PFA coating film.

The fluorine resin coating of the present invention can be subjected to a smoothing treatment if necessary. Smoothing can be achieved by the coating of a wet paint containing PFA particles having a large particle diameter and PFA particles having a small particle diameter, and also by heating and pressing described below, which may be performed alone or in combination. . Since the outermost layer is formed by said specific PFA layer, the fluorine resin coating of this invention can perform the surface smoothing process easily. This smoothing treatment is performed by pressing the surface of the outermost layer at right angles while forming the outermost layer made of the PFA layer, while heating it to a temperature below the crystal melting point of the PFA. The pressurization method is heated at a room temperature or higher, and is heated at the same time by a method such as passing between the press rolls such as a pinch roll or a leveler, a hot press method used for joining dissimilar metals, or the like, and perpendicular to the painted surface. The method of pressurizing to a direction is mentioned. When the smoothing treatment is performed by a hot press method, the heating is usually performed at a temperature of 150 ° C. to 300 ° C., preferably 220 to 280 ° C., at an atmosphere of inert gas such as nitrogen gas and argon gas, at atmospheric pressure or at most 1.5 atm in air. Under reduced pressure, it is generally pressurized at a press pressure of usually 200 to 1,000 kgf / cm 2, preferably 300 to 800 kgf / cm 2, for 5 to 60 minutes, preferably for 10 to 30 minutes.

Although the smoothness of the surface of the fluororesin coating of the present invention depends on the coating conditions, the smoothing treatment conditions, and the like, it is possible to finish the surface roughness Ra in the range of about 0.1 µm to about 5 µm. By the selection of various conditions, it is also possible to make surface roughness of the range of 0.2-3 micrometers suitable for uses, such as an internal cooking pot and a cooking utensil.

The base material, such as a metal base material, can be apply | coated beforehand and adhesiveness with a fluororesin film can be improved. In the case of a metal base material, it is preferable to form fine unevenness | corrugation on the surface of a metal base material by chemical or electrochemical etching process, and to improve adhesiveness with a fluorine resin film. When the etched metal substrate is used, after forming the fluorine resin film on the plate, it can be molded into any shape, and it is easy to perform the smoothing treatment by coating or pressing with a wet paint. The mixing method of the adhesive method and the physical adhesion method by an etching process etc. which coat the primer which mix | blended the comparatively low concentration adhesive agent on the etching process surface can also be used suitably. Primer treatment, an etching process, etc. can be performed according to a conventional method.

The fluorine resin coating of the present invention may be one in which one or more fluorine resin layers are formed between the base material and the outermost layer as desired. Such a fluorine resin layer can be formed by coating fluorine resins such as polytetrafluoroethylene (PTFE), PFA, tetrafluoroethylene / hexafluoropropylene (FEP), alone or in combination of two or more thereof. have. Various conditions, such as the kind, application | coating, baking, etc. of the fluororesin used for a lower layer, can be suitably selected according to a conventional method. As PFA used for a lower layer, although it may be the same kind as an outermost layer, you may use the low molecular weight PFA with large conventional MFR. By using two or more fluororesin layers, coating film defects, such as a pinhole, can be eliminated and abrasion resistance can be improved further. Moreover, functions, such as design, can also be added by coloring the lower fluororesin layer or forming a pattern. In the case of disposing the fluorine resin layer on the lower layer, the number of layers is not particularly limited, but is usually about 1 to 3 layers, and the total of the thickness is usually 5 to 100 µm, preferably about 10 to 60 µm.

According to the present invention, in the fluorine resin coating coated with the fluorine resin layer on the substrate, the fluorine resin coating layer is formed of three or more layers of fluorine resin layers comprising a base coat layer in contact with the substrate, at least one intermediate layer and an outermost layer. In addition, fluorine formed of a fluororesin composition containing at least one additive selected from the group consisting of organic pigments, inorganic pigments, organic fillers and inorganic fillers in a proportion of 0.5 to 10% by weight as at least one intermediate layer. By disposing a resin layer, a fluorine resin coating having excellent abrasion resistance and the like can be obtained. In this case, the outermost layer does not necessarily need to be formed of the above PFA coating film. PTFE, PFA, FEP, etc. are mentioned as a fluororesin which forms each layer.

The intermediate layer may be one layer or a multilayer of two or more layers. The intermediate layer can be used for repairing coating defects such as pinholes, reinforcing abrasion resistance, and providing designability and indicating function. It is not necessary to include an additive in the intermediate layer as long as it is only for the repair of coating defects such as pinholes, but it is necessary to add the additive to reinforce the wear resistance, to impart designability or indicating functionality, and to add at least one layer of the intermediate layer. Contains at least one additive selected from the group consisting of organic pigments, inorganic pigments, organic fillers and inorganic fillers in a proportion of 0.5 to 10% by weight.

Examples of the organic additives include engineering plastics such as polyamideimide, polyimide, polyetherimide, polyether sulfone, polysulfone, polybenzimidazole, polyphenylene sulfide, and polyether ether ketone. These organic additives are normally mix | blended in sub-micron or less microparticles | fine-particles in comparatively large particle shape of several tens of microns. As an inorganic additive, For example, pigments represented by titanium white, titanium yellow, carbon black, iron oxide, ultramarine blue, etc .; Scaly pigments such as mica, pigment coated mica, metal foil, glass foil, graphite, carbon fluoride, etc .: reinforcement of glass particles, metal particles, metal oxide particles, ceramic particles, etc. Solvent fillers; and the like. However, an additive is not limited to said thing, All available additives can be used suitably. If the blending ratio of the additive is too small, it is difficult to obtain the above-described effects, and if it is too large, the coating film strength may be lowered or coating film defects such as adhesion between layers and pinholes may be undesirable. not. Although the compounding ratio of an additive can be set suitably according to the objective, Generally, 1 to 5 weight% is preferable.

As the method for forming the intermediate layer, any coating method or printing method such as screen printing, stamp printing, inkjet printing, spray coating, spin coating, roll coating or the like can be applied. When the intermediate layer is partially coated without coating the entire surface, it is suitable to use printing means such as screen printing, stamp printing, inkjet printing, or the like.

When the fluorine resin coating is used for general purpose cooking utensils such as hot plates, grill pans, auto bakeries, rice cakes, cooking utensils such as pots, cookers, and frying pans, and internal cooking pots, etc. In rice washing etc., an intermediate | middle layer can be partially arrange | positioned in the place which is abrasion-prone or abrasion. In particular, in the case of a fluorine resin coating molded into a container shape such as an inner pot, a pot, a pot, a frying pan, or the like, an intermediate layer is formed at the bottom half or the bottom half of the container shape molding. It is preferable. Although the intermediate | middle layer may be in another part, when there is no intermediate | middle layer containing an additive in the lateral middle part, upper side part, and flange part vicinity which are severe in workability, it is difficult to produce a coating film defect and it is preferable at the point of corrosion resistance. The position and design of the part forming the intermediate layer containing the additive is appropriately determined depending on the usage, use, function, and look of the fluororesin coating, but generally, it is less than or equal to the height center of the side when formed into a container-shaped molding. It is better to arrange the intermediate layer from the bottom to the bottom. It is preferable to arrange | position the intermediate | middle layer containing a filler also from the point which can display the performance of high durability, giving impression by a design.

The intermediate layer made of a fluorine resin composition containing an additive can be formed in a pattern shape. It does not specifically limit as a pattern, Various patterns, a letter, a scale, etc. are mentioned. In terms of design, the pattern of geometric patterns, figures, landscapes, still lifes, illustrations, paintings, photographs, calligraphy or character designs, symbols such as letters, logos of companies, etc. are formed in a pattern form as an intermediate layer. It is preferable. The place of formation may be anywhere, but if it is desired that the picture pattern is not deformed, it is advantageous to produce on the bottom surface. Of course, the pattern can be formed on the side surface or in the vicinity of the flange, but in this case, it is necessary to design a pattern shape that predicts deformation in advance by post-processing or the like.

Examples of the scale include printing a scale for displaying the water level in the track and the like, an example for displaying the explanation, and the like. Moreover, as an example to display on an oil pot etc., it is possible to display the indicator which is easy to understand the heat deterioration color of oil in a bright color, or to be able to know oil deterioration level at a glance using optical illusions, such as gradation.

In the case of the fluorine resin coating having the intermediate layer containing the above filler, the kind of fluorine resin forming the outermost layer may be arbitrary, and may be PTFE, PFA, FEP or a mixture thereof, and may contain additives such as pigments and fillers. You may also In the case where emphasis is placed on non-tackiness and corrosion resistance, it is preferable that the outermost layer does not contain additives such as pigments. The outermost layer may be a PFA layer having a thickness of 10 to 90 µm made of PFA containing PFA having an MFR of 0.2 to 10 g / 10 minutes at a ratio of 20 to 100% by weight in the total amount of PFA, thereby providing durability. It can increase. The base coat layer is formed of PTFE, PFA, FEP, or a mixture thereof, and the thickness thereof is usually 5 to 100 µm, preferably about 10 to 60 µm. The thickness of the intermediate layer is not particularly limited, and is usually 5 to 100 µm, preferably about 10 to 60 µm.

As described above, the fluorine resin coating of the present invention is excellent in wear resistance, scratch resistance, corrosion resistance, blister resistance, and the like, and further studies on the arrangement of the intermediate layer further improves the wear resistance and the like, and further improves the designability, the indicating function, and the like. Can be added. The fluorine resin coating of the present invention can be applied to a wide range of fields, including the field of cooking utensils, by forming a fluorine resin layer on a base material or by molding into molded articles of various shapes.

Although an Example and a comparative example are given to the following and this invention is demonstrated more concretely, this invention is not limited only to these Examples.

In addition, the measuring method of a physical property is as follows.

(1) surface roughness

Surface roughness was measured according to the measuring method of centerline average roughness (Ra) prescribed | regulated to JIS-B-0601. The unit is μm.

(2) pinhole diagram

The fluorine resin coating was immersed in a 2.5% by weight aqueous sodium chloride solution, the metal base of the fluorine resin coating was used as the cathode, the electrode was placed in an aqueous solution as the anode, and the current flowing from the pinhole part was energized at 10V for 5 seconds. It was calculated in terms of unit area. The unit is dl / cm 2.

(3) scorch bright abrasion test

The scorch bright was rotated in contact with the surface of the fluororesin coating layer, and the amount of wear at that time was expressed by the number of revolutions required to cut the PFA layer having a thickness of 1 µm. The unit is 10 ³ revolutions / micrometer.

(4) corrosion resistance

Dip 25 g of Odennomoto (trade name) (manufactured by Japan House Food Industry Co., Ltd.) in a test solution dissolved in 1 liter of water, and keep it at 90 to 100 ° C to measure the time until corrosion occurs on the coating surface. .

Example 1

As an aluminum base material, an aluminum disc of 1.2 mm in thickness (manufactured by Sumitomo Light Metal Industries, Japan, MG-110) was used. First, using this aluminum disc as an anode, electrochemical etching was carried out in an ammonium chloride aqueous solution and an electric quantity of 25 coulombs / cm 2 to form fine irregularities on the surface of the aluminum disc. On this fine uneven surface, spin-coated a PTFE dispersion (D-1F manufactured by Nippon Diking Co., Ltd.) containing no filler, and then dried the moisture, baked at 400 ° C for 10 minutes, and had a thickness of 25 µm. Phosphorus coating film (1st layer) was formed.

Next, 33.3 weight% of PFA powder (M-103 by Dupont, M-103) whose average particle diameter is 15 micrometers and melt-florate is 1.6g / 10min, 34.8 weight% of water, and a fluorine-type surfactant (made by Diking Industries, Ltd.) , 1.0% by weight of Unidine DS-401) and 0.5% by weight of a hydrocarbon-based surfactant (Nippon Chemical, Nonion K-204) were dispersed in a liquid medium, which had an average particle diameter of 0.4 µm and melted liquid. 30.4% by weight of PFA dispersion (AD-2CR, manufactured by Diking Industry Co., Ltd.), consisting of 47% by weight of PFA spherical particles, 25% by weight, and 7% by weight of surfactant, and 47% by weight of water, was thoroughly mixed with fluorine. Resin fee was prepared. The weight ratio of PFA particles having an average particle diameter of 15 µm and PFA particles having an average particle diameter of 0.4 µm was 70:30. This fluorine resin was spin-coated on the first layer, and then dried for 30 minutes at 390 ° C to form a coating film (second layer) having a thickness of 15 µm. The results are shown in Table 1.

Comparative Example 1

Example 1 WHEREIN: Except having used what substituted two types of PFA particle into PFA particle whose average particle diameter is 13 micrometers, and melt-florate is 13 g / 10min as a fluorine resin material which forms a 2nd layer. In the same manner as in 1, a fluorine resin coating was produced. The results are shown in Table 1.

No. Powder PFA Scotch Bright Abrasion Test (10 ³ revolutions / μm) Pinhole diagram (㎃ / ㎠) Surface Roughness Ra (㎛) Comparative Example 1 MP-102 1.0 0 1.0 to 1.2 Example 1 MP-103 2.1 0 2.3 to 2.5

As shown in Table 1, the use of MP-103 with a small MFR (Example 1) is about twice as high as the PFA particles used with MP-102 with a large MFR (Comparative Example 1). It can be seen that the improvement.

Example 2

The surface roughness Ra of the outermost layer (second layer) of the fluorine resin coating obtained in Example 1 was 2.3-2.5 micrometers. On the upper surface of the fluorine resin coating, a SUS plate having a surface roughness (Ra) of 1.0 μm was superposed and hot-pressed for 20 minutes under a press pressure of 500 kgf / cm 2 under heating at 270 ° C. and a reduced pressure of 0.5 atm. The surface roughness Ra of 1.2-1.5 micrometers was obtained and the smoothness was improved.

Example 3

As an aluminum base material, an aluminum disc of 1.2 mm in thickness (manufactured by Sumitomo Light Metal Industries, Ltd., MG-110) was used. First, using this aluminum disc as an anode, electrochemical etching was carried out in an ammonium chloride aqueous solution and an electric quantity of 25 coulombs / cm 2 to form fine irregularities on the surface of the aluminum disc.

33.3% by weight of PFA powder (M-103, manufactured by DuPont, M-103) having an average particle diameter of 15 µm and a melt flow rate of 1.6 g / 10 minutes, 34.8% by weight of water, and a fluorine-based surfactant (manufactured by Diking Industries, Ltd.) -401) dispersed in a liquid medium consisting of 1.0% by weight and 0.5% by weight of a hydrocarbon-based surfactant (Nippon K-204, Nonion K-204), to which an average particle diameter of 0.4㎛, about 30.4% by weight of PFA dispersion (AD-2CR, manufactured by Diking Co., Ltd.) consisting of 47% by weight of PFA spherical particles, 25% by weight, and 6% by weight of surfactant, and 47% by weight of water was added, and the mixture was sufficiently mixed to prepare a fluorine resin. Prepared. The weight ratio of PFA particles having an average particle diameter of 15 µm and PFA particles having an average particle diameter of 0.4 µm was 70:30.

The fluorine resin was spin-coated to the fine concavo-convex surface of the aluminum disc, dried, and then baked at 390 ° C. for 30 minutes to form a coating having a thickness of 25 μm. The sample in which this coating film was formed was press-molded in the pot shape, and corrosion resistance evaluation was performed. As a result, in the corrosion resistance test of 90 hours, almost no corrosion was found and what was provided for practical use was obtained.

Comparative Example 2

In Example 3, a fluororesin coating was produced in the same manner as in Example 3, except that the two kinds of PFA particles were replaced with PFA particles (MP102) having an average particle diameter of 13 µm and a melt flow rate of 13 g / 10 minutes. Similarly evaluated. As a result, in the corrosion resistance test of 90 hours, almost no corrosion was found and what was provided for practical use was obtained. That is, compared with the comparative example 2, it turns out that the fluorine coating of Example 3 was able to achieve the corrosion resistance comparable to a conventional product.

Example 4

As an aluminum base material, an aluminum disc (MG-110, manufactured by Sumitomo Light Metal Industries, Ltd.) having a plate thickness of 1.2 mm and a diameter of 360 mm was used. First, using this aluminum disc as an anode, electrochemical etching was carried out in an ammonium chloride aqueous solution and an electric quantity of 25 coulombs / cm 2 to form fine irregularities on the surface of the aluminum disc. On this fine uneven surface, a PTFE dispersion (D-1F, manufactured by Diking Industries, Ltd.) containing no filler was spin-coated, dried, and then baked at 400 ° C for 10 minutes to form a coating film having a thickness of 25 µm ( 1st layer) was formed.

PFA powder (made by DuPont, MP-103) to 25.4% by weight of PFA dispersion (D-2CR) made by 47% by weight of PFA spherical particles, 6% by weight of surfactant, and 47% by weight of water 28.1 weight%, pigment coating mica (manufactured by Japan Melk Japan Co., Ltd., IRIODIN503) 4.4 weight%, surfactant (made by Daiking Industry Co., Ltd., Udine DS-401; and octapol 80 made by Sanyo Kasei Co., Ltd.) 42.1 weight % Was mixed and the fluororesin containing a filler was prepared. After coating this fluorine resin material in the range of 180 mm in diameter from the center of a disk by screen printing on said 1st layer, it baked at 390 degreeC for 15 minutes, and formed the coating film (2nd layer) of 5 micrometers in thickness. .

33.3 weight% of PFA powder (Made by Dupont, MP-103) which has an average particle diameter of 15 micrometers, and a melt-florate 1.6g / 10min, 34.8 weight% of water, and a fluorine-type surfactant (made by Diking Industries Co., Ltd.) DS-401) 1.0% by weight and 0.5% by weight of a hydrocarbon-based surfactant (Nippon Co., Ltd., Nonion K-204) are dispersed in a liquid medium, which has an average particle diameter of 0.4 µm and a melt flow rate of about 30.4% by weight of PFA dispersion (AD-2CR, manufactured by Diking Co., Ltd.) consisting of 47% by weight of PFA spherical particles having 25 g / 10 minutes, 6% by weight of surfactant, and 47% by weight of water was added and mixed sufficiently to prepare a fluorine resin. Prepared. The weight ratio of the PFA particles having an average particle diameter of 15 µm and the PFA particles having an average particle diameter of 0.4 µm was 70:30. This fluorine resin was spin-coated on the second layer, dried, and then baked at 390 ° C. for 30 minutes to form a coating film (third layer) having a thickness of 15 μm.

In the scorch bright abrasion test of the fluorine resin coating thus obtained, the required number of revolutions until the base of aluminum was visible was investigated. The results are shown in Table 2. In addition, Table 2 shows the evaluation result by this measuring method also about the fluororesin coating material obtained by the comparative example 1 and the Example 1.

No. Film thickness (㎛) Scotch bright abrasion test rotation speed (10 ³ rotations) Comprehensive Evaluation Comparative Example 1 40 20 × Example 1 40 36.5 ○ Example 4 45 44 ◎

Further, by press-molding the fluorine resin coating of Example 4 in the shape of a pot, the entire bottom surface portion was covered with the second fluorine resin layer (intermediate layer) containing the pigment coated mica, A distinctive appearance was not found in the prior art that the color tone is different.

Example 5

In Example 4, using the fluorine resin material of the second layer, by screen printing, graduations and letters are painted at predetermined positions within a range of 200 mm in diameter from the center of the original plate, and baked at 390 ° C. for 15 minutes, Subsequently, the fluorine resin coating was produced in the same manner as in Example 4 except that the fluorine resin coating of the third layer was applied. The obtained fluorocarbon resin coating was press-molded with a frying pot. Using this frying pot, it was found that the way the letters looked different depending on the oil contamination condition, and the scales and letters in the middle layer played the role of oil pollution indicators.

According to the present invention, it is possible to provide a fluororesin coating having excellent abrasion resistance, scratch resistance, corrosion resistance, blister resistance and the like and a method of manufacturing the same. Moreover, according to this invention, the fluorine resin material which can form the fluorine resin film excellent in such various characteristics can be provided. Fluorine resin coating of the present invention, a cooking utensil such as a pot, a pot, a frying pan, a half-pot inner pot; Home appliance cooking appliances such as hot plates, grill pans, auto bakeries and rice cakes; As an oil pot etc., it is applicable to a wide range of fields.

Claims (13)

In a fluororesin coating material in which one or more fluororesin layers are coated on a substrate, the outermost layer is tetrafluoroethylene / purple having a melt flow rate of 0.2 to 10 g / 10 minutes as specified in ASTM-D-3307. A fluororesin coating comprising a fluoroalkyl vinyl ether copolymer (PFA) in a total amount of PFA containing 20 to 100% by weight of PFA layer having a thickness of 10 to 90 µm. The fluorine dispersed in the liquid medium according to claim 1, wherein the outermost PFA layer comprises PFA particles having an average particle diameter of 5 to 40 µm and PFA particles having an average particle diameter of 0.1 to 0.5 µm in a weight ratio of 20:80 to 80:20. Fluorine resin coating, characterized in that formed using a resin coating material. 3. The PFA particles according to claim 2, wherein the melt flolate defined in ASTM-D-3307 of the PFA particles having an average particle diameter of 5 to 40 µm is 0.2 to 10 g / 10 minutes, and the PFA particles having an average particle diameter of 0.1 to 0.5 µm. A fluorine resin coating, characterized in that the melt florate specified in ASTM-D-3307 is 0.2 to 40 g / 10 minutes. In the method for producing a fluorine resin coating coated with one or two or more layers of fluorine resin layers on a substrate, the melt flow specified in ASTM-D-3307 directly or on at least one layer of fluorine resin layers on the substrate. A fluorine resin made of PFA containing PFA having a rate of 0.2 to 10 g / 10 minutes at a ratio of 20 to 100% by weight in the total amount of PFA was applied and baked to form an outermost layer made of a PFA layer having a thickness of 10 to 90 µm. Method for producing a fluorine resin coating, characterized in that. 5. The fluorine resin made of PFA has an average particle diameter of 5 to 40 µm and a PFA particle having an average particle diameter of 0.2 to 10 g / 10 minutes and an average particle diameter of 0.1 to 10 µm, as defined in ASTM-D-3307. Method for producing a fluororesin coating, characterized in that the fluororesin coating material containing PFA particles having a melt flow rate of 0.2 ~ 40g / 10 minutes specified in ASTM-D-3307 in a weight ratio of 20:80 to 80:20 . 6. The fluorine resin coating according to claim 5, wherein the fluorine resin coating material is a fluorine resin coating material in which PFA particles having an average particle diameter of 5 to 40 mu m and PFA particles having an average particle diameter of 0.1 to 0.5 mu m are dispersed in a liquid medium. Way. The method according to any one of claims 4 to 6, wherein after forming the outermost layer made of the PFA layer, it is pressurized to the surface of the outermost layer at a right angle to the smoothing treatment while heating at a temperature lower than the crystal melting point of the PFA. Method for producing a fluorine resin coating characterized in that. The plate-like metal substrate having fine irregularities formed on the surface by chemical or electrochemical etching as a substrate is used, and after forming an outermost layer made of a PFA layer, A method for producing a fluorine resin coating, which is molded to a desired shape. PFA particles having an average particle diameter of 5 to 40 탆 and a melt fluorate specified in ASTM-D-3307 of 0.2 to 10 g / 10 min, and melt fluorates specified to ASTM-D-3307 as an average particle diameter of 0.1 to 0.5 탆. PFA particles having a weight ratio of 0.2 to 40 g / 10 minutes are dispersed in a liquid medium in a weight ratio of 20:80 to 80:20. In a fluorine resin coating coated with a fluorine resin layer on a substrate, (1) The fluorine resin coating layer is formed of three or more layers of fluorine resin layers composed of a base coat layer in contact with a substrate, at least one intermediate layer, and an outermost layer, and (2) At least one intermediate layer is formed of a fluororesin composition containing at least one additive selected from the group consisting of organic pigments, inorganic pigments, organic fillers and inorganic fillers in a proportion of 0.5 to 10% by weight. Fluorine resin coating, characterized in that. The fluorine resin according to claim 10, wherein an intermediate layer made of a fluorine resin composition containing an additive is formed at the bottom of the inner surface of the fluorine resin coating molded in the shape of a container or at the lower half of the bottom and side surfaces. Resin coatings. The fluorine resin coating according to claim 10, wherein an intermediate layer made of a fluorine resin composition containing an additive is formed in a pattern shape. The outermost layer according to any one of claims 10 to 12, wherein the melt flow rate as defined in ASTM-D-3307 is 0.2 to 10 g / 10 minutes of PFA in a proportion of 20 to 100% by weight in the total amount of PFA. A fluorine resin coating comprising a PFA layer having a thickness of 10 to 90 µm comprising PFA.