JPH03193444A - Manufacturing method of metal plate for plastic working - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (al) Purpose of the Invention (Field of Industrial Application) The present invention relates to plastic processing used in the manufacture of various kitchen appliances such as rice cookers and frying pans, and various building materials such as roofing materials and wall materials. The present invention relates to a method for producing a resin-coated metal plate for use in other applications.

(Prior art) Fluororesin has excellent heat resistance, chemical resistance, weather resistance, non-adhesiveness, and sliding properties, and has been used in the manufacture of various kitchen appliances, building materials, sealing materials, etc. It is used for this purpose.

To manufacture kitchen appliances using fluororesin, fluororesin is coated on a roughened flat metal plate and then baked to create a fluororesin-coated flat metal plate, which is then plastic-processed into a predetermined shape and made into a product. The method is - used in boat fishing.

Plastic processing during the production of such kitchen appliances causes large deformation of the metal plate, so it is common to roughen the surface of the metal plate in advance in order to maintain sufficient adhesion between the metal plate and the fluororesin. It is true.

In addition, kitchen utensils, etc. are
For example, it is desirable to display a scale, letters, etc. as a guide for adding food ingredients such as rice, water, etc. For this reason, traditionally, stamps were made using impact force using a press machine, etc.
It is common practice to display the above-mentioned scales, characters, etc. on a fluororesin-coated metal plate to be plastically worked.

However, in this case, there was a drawback that the scales and characters obtained by engraving were unclear, and the fluororesin coating was damaged by the die used for stamping, and the fluororesin coating originally had There was a drawback that the properties of the fluororesin coating were impaired and the performance of the fluororesin coating film on the engraved area was significantly reduced.

In addition, in order to manufacture building materials such as roofing materials, a metal plate that has been wound into a coil is continuously unwound and subjected to degreasing and chemical conversion treatment, and then coated with fluororesin, baked, and once rolled up. A commonly used method is to rewind it again and cut it into a predetermined shape and size, and then plastically process the obtained fluororesin-coated metal plate to finish it into a roofing material or the like.

(Problems to be solved by the invention) The present invention provides a metal plate for plastic working that allows a metal product coated with a heat-resistant resin to be easily obtained with a desired mark, character, figure, design, pattern, etc., simply by plastic working. The purpose is to provide the following.

(b) Structure of the invention (means for solving problems) The metal plate in the present invention is not particularly limited, and various metal plates can be used. For example, an aluminum plate, an aluminum alloy plate, a stainless steel plate, a laminate of these metals (ie, a craft plate), etc. can be used. The metal plate is usually preferably in the form of a flat plate (including a coiled material).

In order to manufacture the metal plate for plastic working of the present invention, the raw metal plate (including a coiled metal plate) is previously subjected to treatments such as degreasing, chemical conversion treatment, and surface roughening treatment, as required. Examples of surface roughening treatment methods include chemical etching,
Etching methods such as electrolytic etching, mechanical surface roughening methods such as barrel grinding, hairline method, shot blasting, or a combination of these methods may be used. The degree of roughening is important for improving the adhesion with the colorant and fluororesin, and the surface is usually roughened to an average roughness (Ra) of 0.5 to 5μ, preferably 1 to 3μ. It is desirable to keep it.

A heat-resistant resin clear film provided with a display layer of desired marks, letters, figures, designs, patterns, etc. by coating with a coloring agent is attached to the metal plate which has been subjected to such preliminary treatment, preferably surface roughening treatment.

The heat-resistant resin is preferably a fluororesin, such as polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (F
EP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), ethylene-
Examples include tetrafluoroethylene copolymer (ETFE). In addition to fluororesin, for example, polyimide,
Polyamideimide, polyethersulfone, polyphenylene sulfide, polyarylate, polysulfide, polyarylsulfone, polysulfone, polyetherimide, polyetheretherketone, polyphenylene ether, etc. can be used. The heat-resistant resin is used alone or in combination, and the thickness is usually 10 to 200μ, according to a conventional method.
Preferably, the film is formed into a film having a thickness of 20 to 100 μm and used in the present invention. A small amount of coloring agent can be added to the film as long as it does not impair transparency. The clear film has a total light transmittance (measured with a haze meter) of 40 to 100 as specified by JIS K-7105.
% means.

Coloring agents include organic or inorganic coloring components, binders, fillers, and various additives to a solution or dispersion of a heat-resistant polymer with a polar group that provides close contact with metals and heat resistance in a solvent. Those containing appropriate agents and the like are preferably used. As the heat-resistant polymer, in addition to the above-mentioned heat-resistant resins, epoxy resins, phenol resins, unsaturated polyester resins, etc. are used. As the coloring component, copper phthalocyanine blue, phthalocyanine green, quinacridone red, carbon black, ferrous oxide, titanium oxide, navy blue, yellow lead, etc. can be used.

Various methods can be used to apply the colorant, but a gravure coating method is preferred in the case of a coiled metal plate, and a screen method is preferred in the case of a cut sheet metal plate. In the gravure coating method, the choice of gravure roll is
Also, in the screen printing method, the selection of the plate is important. In both methods, the viscosity and concentration of the colorant are also important; if the viscosity is too low, sagging will occur, and if the viscosity is too high, printing will be difficult. Its viscosity is usually 10 to 200 boids,
Preferably it is 20 to 100 voices. To adjust the viscosity,
This can be easily carried out by controlling the concentration of the heat-resistant polymer dissolved in the solvent. The coating thickness of the colorant is desirably as thin as possible, and is usually about 1 to 5 microns in dry coating thickness.

A display layer is formed by applying a colorant to a clear film of a heat-resistant resin, but the timing of application is not particularly limited. A coloring agent is applied to a clear film in advance to form a display layer with required marks, letters, figures, designs, patterns, etc. on the film, and the clear film with the display layer thus obtained is coated with a metal. It is preferable to attach it toward the board side. However, the present invention is not limited thereto, and after pasting a clear film on a metal plate, a coloring agent may be applied to the film to form a display layer for characters, figures, patterns, etc.

A heat-resistant resin clear film for forming a display layer is usually attached to the entire surface of a metal plate.
The size of the display does not necessarily cover the entire surface of the metal plate, but rather often occupies only a portion of the metal plate. Therefore, the present invention also includes an embodiment in which the clear film provided with the display layer or to be provided with the display layer is applied only to a portion of the metal plate, and the application to other portions is omitted. However, in this case, since the heat-resistant resin film is not attached to the area where the display layer is not provided, it is necessary to apply a top coat as described below over the entire surface of the metal plate.

In the present invention, a clear fluororesin coating layer can be further formed as a top coat on the display layer. As such a fluororesin, any of the above-mentioned fluororesins listed as heat-resistant resins can be suitably used.

The clear fluororesin coating layer has a total light transmittance (measured with a haze meter) of 40 to 100%, similar to the heat-resistant resin clear film described above. Methods for forming such a coating layer include a method of applying a fluororesin and a method of pasting a fluororesin film.

The clear fluororesin can be applied by coating the above-mentioned fluororesin in the form of a dispersion, solution, etc. using an appropriate method using water, a solvent, a surfactant, etc., and applying it by spraying, flow coating, Coating is performed using methods such as roll coating, spin code, and die coating. The coating thickness of the clear fluororesin to be applied is approximately 5 to 100 μm when dried or baked.

The clear fluororesin coating film is then cured at a low temperature around room temperature, or heated and baked at an appropriate temperature (
However, in the case of a coiled metal plate, it is then further cut into a predetermined shape and size. ), it becomes the desired metal plate for plastic working.

The temperature conditions for curing or baking a clear fluororesin coating vary depending on the type of fluororesin, and the following temperatures are usually used.

■Polytetrafluoroethylene (PTFE) 350-4
50℃ ■Tetrafluoroethylene-hexafluoropropylene copolymer (FEP) 350-450℃ ■Tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) 350-450℃ ■Ethylene-tetrafluoroethylene copolymer (ETF)
E) 250-350℃ ■ Polyvinyl fluoride (PVF) 200-300℃ ■ Fluoroethylene-hydrocarbon vinyl ether copolymer Room temperature ~ 250℃ Note that ■ Fluoroethylene-hydrocarbon vinyl ether copolymer coating film ,
Based on the carboxyl group, hydroxyl group, amino group, etc. introduced into the copolymer derived from the hydrocarbon vinyl ether, it is possible to react and cure even at room temperature. However, if curing at room temperature takes too long, heating can accelerate the curing reaction.
It can be cured in 10 minutes.

In addition to forming the clear fluororesin coating layer by applying and curing the fluororesin as described above, it can also be formed by processing the fluororesin into a film in advance and pasting this. The above-mentioned fluororesins (1) to (2) can all be processed into films according to conventional methods, but the resin (2) is not preferred for film application. The film can be fixed by heat-pressing at the predetermined temperature.

The metal plate for plastic working of the present invention obtained as described above can be easily finished into a final product by plastic working, and the final product can include required marks, characters, figures, designs, patterns, etc. A display layer is provided, and the coloring of the display layer is clear.

Examples of the plastic working method for the metal plate for plastic working include methods such as bending, spinning, drawing, and roll forming.

(Examples, etc.) Examples will be described in detail below.

Example 1 Aluminum alloy (JIS-A3003
) with a diameter of 430 mm and a thickness of 1 mm, the surface of which was roughened in advance by shot blasting and chemical etching treatment so that the average roughness (Ra) was 2.9 μm.

On the other hand, as a clear film of heat-resistant resin, the thickness is 50 μm.
An ethylene-tetrafluoroethylene copolymer film was used, and a colorant having the following composition (viscosity 30 poise)
After that, the colorant coating layer (dry film size: 1μ) was dried at 180° C. for 30 minutes.

Composition of coloring agent Polyimide 30 parts by weight Polytetrafluoroethylene 70 parts by weight N-methylpyrrolidone 50 parts by weight Coloring component
0.5 parts by weight (copper phthalocyanine blue) Place the above film at 30°C with the colorant-applied side facing the metal plate.
It was pressed onto an aluminum disc preheated to 0°C using a heat-resistant rubber roll, and then reheated at 300°C for 10 minutes to complete the fusion.

This fluororesin-coated disk was formed into a container with a bottom diameter of 200 mm and a height of 150 mm by a cylindrical deep drawing press method.

The obtained container had clear blue scales formed at predetermined positions on the side surface, and the scales did not peel off during use of the container.

Example 2 As a colorant, a colorant having the following composition (viscosity 30 poise)
A fluororesin-coated disk was produced in the same manner as in Example 1 using the following procedure, and the disk was press-molded in the same manner.

Composition of colorant Epoxy resin 30 parts by weight (Epicote L OQ 1") Ethylmethylimidazole 2 parts by weight Polytetrafluoroethylene 70 parts by weight N-methylpyrrolidone 50 parts by weight Coloring component
0.5 parts by weight (w4 phthalocyanine blue) Butyl cellosolve 50 parts by weight Neto...
Yuka Shell Epoxy Co., Ltd. (trade name) The obtained container had clear blue scales formed at predetermined positions on the side surface, and the scales did not peel off during use of the container.

Example 3 A polyamide-imide film was used instead of the ethylene-tetrafluoroethylene copolymer film as a heat-resistant resin clear film, and a scale was made in the same manner as in Example 1 using a self-composed colorant. displayed.

Composition of colorant: Polyimide: 30 parts by weight Polytetrafluoroethylene: 70 parts by weight N-methylpyrrolidone: 50 parts by weight Coloring component (carbon black): 0.5 parts by weight The above film was heated at 350°C with the side to which the colorant was applied facing the metal plate side. It was crimped onto a preheated aluminum disc using a heat-resistant rubber roll. Furthermore, an aqueous dispersion of polytetrafluoroethylene (resin concentration 60
% by weight) was applied by an air spray method, and after the coating film was dried, it was baked by heating at 380° C. for 10 minutes, and a fluororesin was coated as a top coat. The dry film thickness of the clear fluororesin was 15μ.

Hereinafter, a container was manufactured by cylindrical deep drawing press molding in the same manner as in Example 1, and the container had a clear black scale and was of high utility value.

(C) Effects of the invention The metal plate for plastic working of the present invention can produce marks and marks just by plastic working.
The final product may have a display of characters, figures, designs, patterns, etc. The display can be formed from a clearly colored layer, and the display will not peel off even after long-term use.

Claims (4)

[Claims] (1) Manufacture of a metal plate for plastic working, which is characterized by pasting a heat-resistant resin clear film on which a layer for displaying characters, figures, patterns, etc. is provided by coating a colorant on a roughened metal plate. Law. (2) The manufacturing method according to claim (1), characterized in that the colorant is applied with the surface to which the colorant is applied facing the metal plate. (3) A metal for plastic working characterized by pasting a heat-resistant resin clear film on a roughened metal plate and applying a coloring agent to the film to provide a display layer for characters, figures, patterns, etc. Method of manufacturing boards. (4) Claim (1) or claim (3) characterized in that a clear fluororesin coating layer is further provided on the display layer.
) manufacturing method.