JPH0419145A - Film-covered metal plate and manufacture thereof - Google Patents

Abstract

PURPOSE:To acquire strong heat fusion-bonding force and, at the same time, make the long term outdoor use of the film-covered metal plate concerned possible by a method wherein at least process for heating the metal plate is carried out in atmosphere, in which no oxygen is present substantially, when the metal plate is coated with thermoplastic resin film. CONSTITUTION:As the pretreatment of metal plate, surface roughening is carried out in addition to the cleaning, polishing, surface plating, acid treatment and the like of the surface of the metal plate. As the pretretment of thermoplastic resin film, the removal of oily matter, foreign matter and the like from, corona discharge treatment of, application of surface treatment to the surface of film or the like is carried out. As the covering of the metal plate with the thermoplastic resin film, both of which are pretreated as mentioned above, at least process for heating the metal plate and process for laminating thermoplastic film to heated metal plate are carried out in atmosphere, in which no oxygen is present substantially. In this case, the atmosphere preferably having oxygen content of 0.2% or less is necessary as 'atmosphere, in which no oxygen is present substantially'. For that, the filling with inert gas such as nitrogen gas or the like or the realization of vacuum state is necessary. The preferable vacuum state has the pressure of 1 Torr or less.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a metal plate coated with a film and a method for manufacturing the same, and more particularly to a metal plate coated with a thermoplastic resin film and a method for manufacturing the same.

[Conventional technology]

Conventionally, various metal plates coated with thermoplastic resin films have been proposed, such as metal plates coated with adhesives, metal plates covered by heat-sealing films, and the like.

However, the adhesive strength of metal plates coated with adhesive decreases over time, and this decrease becomes significant, especially when used outdoors, making it extremely difficult to use for long periods of time. Moreover, when coating a thermoplastic resin film, especially a fluorine-containing resin film, tW! The current situation is that the adhesive is not found.

In addition, various metal plates have been proposed in which the metal plate is coated by heating the metal plate in advance and heat-sealing it with a film.
-58227, etc. However, in these methods, metal plates and films are heated at high temperatures in the atmosphere, that is, in the substantial presence of oxygen, so that high-temperature reaction products such as oxides on the surfaces of metals and films are generated. occurs, and the strength of the heat-fused layer between the metal plate and the film is extremely reduced, so it has not been widely used in practical use, and the industry has been eager to research and develop it. .

[Problem to be solved by the invention]

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a novel film-coated metal plate and a method for manufacturing the same, which have been completely unknown heretofore.

[Means for solving problems]

The present invention was made to solve the above-mentioned problems, and when coating a metal plate with a thermoplastic resin film,
The present invention provides a film-coated metal plate characterized in that at least the heating step of heating the metal plate is performed in an atmosphere substantially free of oxygen. Therefore, according to the present invention, there is a film-coated metal plate that has strong thermal adhesion and can be used outdoors for a long period of time, and it is possible to coat a wide metal plate with a film easily and continuously in an industrial manner. This gives us a way to do it. Next, the constituent factors of the present invention will be explained in detail.

The "metal plate" used in the present invention is not particularly limited, and any metal plate can be used, but common metal plates include iron-based, aluminum-based, copper-based, titanium-based, and nickel-based metal plates. Among them, iron-based metal plates, aluminum-based metal plates, and copper-based metal plates are preferable, and iron-based metal plates are particularly preferable. The above-mentioned iron-based metal plate may be any metal plate that mainly contains iron in its composition, and specifically includes, for example, a cold rolled steel plate, a galvanized steel plate, and a zinc alloy plated steel plate. , aluminum plated steel plate, copper plated steel plate,
There are stainless steel sheets, phosphate-treated steel sheets, aluminum-zinc alloy plated steel sheets, etc. Among them, galvanized steel sheets,
Zinc alloy plated steel sheets, aluminum plated lead steel sheets and aluminum-zinc alloy plated steel sheets are preferred.

Further, the aluminum-based metal m may be any metal as long as it contains mainly aluminum metal in its composition, but generally, for example, on September 30, 1981, ) Aluminum described in pages 13 to 22 of "Aluminum Handbook (2nd edition)" published by the Light Metals Association, specifically, pure aluminum, (Cu/-Cu)
) system, (Al-Mn) system, (Al-8i) system, (
Human J-Mg) system, (AJ-Mg-8i) system and (Human J
-Zn-Mg) type, among others, pure aluminum type,
(Al-Mn) and (Al-Mg) systems are preferred.

Further, the copper-based metal may be any metal as long as it mainly contains steel, but common examples include pure copper, brass, bronze, and brass. There are metals such as

Although the thickness of the metal plate in the present invention is not particularly limited, the general thickness is, for example, 0.15 to 4t, preferably 0.2 to 2.29.

In the present invention, the term "thermoplastic resin" is not particularly limited. Any thermoplastic resin may be used, but for example,
- published by LINC, ), [Modern Plastics Encyclopedia (Modern Plastics E
ncyclopedia) J Volume 66 & 11, No. 60
The thermoplastic resin described on pages 0 to 643, specifically,
Fluorine-containing, vinyl, acrylate, urethane,
Ester type, cellulose type, styrene type, olefin type, amide type, acetal type, aryl type, epoxy type,
Thermoplastic resins such as carbonate-based, imide-based, and mixtures thereof are preferred, and among them, fluorine-containing, vinyl, and acrylic thermoplastic resins are preferred, and fluorine-containing thermoplastic resins are preferred.

The fluorine-containing thermoplastic resin referred to in this application is not particularly limited as long as it is a thermoplastic resin containing fluorine in its molecular structure, but specifically, it includes, for example, ethylene-tetrafluoroethylene-based thermoplastic resin. Polymers, ethylene-chlorotrifluoroethylene copolymers, hexafluoropropylene-tetrafluoroethylene copolymers, perfluoroalkyl vinyl ether-tetrafluoroethylene copolymers, polyvinylidene heptadide, polyvinyl fluoride, etc. Any of these can be used in the present invention, but ethylene-tetrafluoroethylene copolymers, perfluoroalkyl vinyl ether-tetrafluoroethylene copolymers, polyvinylidene fluoride, and polyvinyl fluoride are particularly preferred. In particular, ethylene-tetrafluoroethylene copolymers are preferred.

The ethylene-tetrafluoroethylene copolymer is made of ethylene and tetrafluoroethylene, and the molar ratio of ethylene/tetrafluoroethylene is generally 40/6.
0~60/40! and, if necessary, a small amount (usually 10 moles or less) of a third comonomer component is copolymerized with this. In the present invention, in particular, ethylene/
The molar ratio of tetrafluoroethylene is 40/60
~6o/40, preferably 45155~s s/4
5 and has the formula CHaxCH-CnFsn+
1 (wherein n is an integer from 2 to 10) perfluoroalkylvinyl monomer units (e.g.
CHs” CH-C4Ho or CHs w OH-
Cs (units derived from H2S) content is 0.1~
An ethylene-tetrafluoroethylene copolymer in the range of 10 mol-1, preferably 0.3 to 5 mol-1 is preferably used. This ethylene-tetrafluoroethylene copolymer is known per se, and can be produced, for example, by the method described in Japanese Patent Publication No. 59-50163.
It is also possible to use a product commercially available under the trade name 0PJrj.

The vinyl thermoplastic resin is a thermoplastic resin having a vinyl group in its molecular structure, such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetate, polyvinyl ether, and polyvinyl ketone. Among them, polyvinyl chloride is preferred.

Examples of the acrylic thermoplastic resins include acrylic ester resins, methacrylic ester resins, and acrylic acid ester resins, and examples of acrylic ester resins include polyacrylic ester resins, Examples of methacrylic ester resins include polymethacrylic ethyl and polymethacrylic ethyl.

Molding of the film from the above-mentioned thermoplastic resin can be carried out in accordance with methods known per se, such as extrusion molding, inflation silane molding, and the like. When forming a film, coloring agents (for example, fermented titanium, zinc white, carbonized calcium, precipitated silica, carbon black, chrome yellow, phthalocyanine blue, phthalocyanine green, etc.) may be added to the Shiko base resin as necessary. can. The thickness of the film is not particularly limited, but the general thickness is 5 to 1,000μ, preferably 10
-250μ, more preferably 15-150μ.

In addition, it is also possible to print on the front and/or back sides of the film to enhance the decorative properties.

Next, an example of the process of coating a metal plate with a thermoplastic resin film according to the present invention will be described.

+II Pre-treatment process This process is necessary to coat the metal plate and thermoplastic resin film more strongly. This is a process that is carried out accordingly.

■ Pre-treatment process of metal plates The purpose of pre-treatment of metal plates is to clean and remove oily substances, foreign substances, oxide films, etc. adhering to the surface, and to expose the base metal to the surface by polishing etc. In addition, surface treatments such as surface plating and polishing are performed, and if necessary, roughness is added to the surface.

■ Surface cleaning There are no particular limitations, and cleaning methods conventionally used for specific metals are used. For example, as a degreasing method,
Degrease and clean using organic solvents, alkaline aqueous solutions, surfactants, etc.

■ Surface polishing For example, mechanical and chemical polishing can be used to polish the surface and expose the bare metal on the surface.

■Surface Treatment If necessary, chemical conversion treatments such as plating treatment, film treatment to install a metal oxide film layer, and rust prevention treatment can be performed on the surface covered with the film. For example, specific examples of chemical conversion treatments for iron-based metals include phosphate treatment with zinc phosphate, calcium phosphate, etc., and chromate treatment with reactive chromate, coating type chromate, and the like.

[Co., Ltd.] Roughening the surface by a surface roughening method using physical means such as brushing, sandblasting, and sheet blasting, or a surface roughening method using a chemical or electrochemical etching method, or a combination thereof. be able to.

■ Film pre-treatment process Removing oily matter, foreign matter, etc. adhering to the film surface, applying an oxide film etc. by corona discharge treatment, chemical treatment, etc., and using various surface treatment agents. For example, treatments such as coating aminosilane, vinylsilane, mercaptosilane, etc. can be performed.

(2) Heating process This is a process in which the pre-treated metal plate is heat-treated in an atmosphere substantially free of chips, and if necessary, the film is also heat-treated.

■Heating atmosphere In this application, the atmosphere is not particularly limited as long as it is substantially free of argon, but in order to create a heating atmosphere, it is filled with an inert gas or It can be strained and heated under vacuum. The inert gas Wi may be any one, but generally includes nitrogen gas, argon gas, neon gas, helium gas, etc. Among them, nitrogen gas and argon gas are preferable, and nitrogen gas is particularly preferable.

In addition, the vacuum state is 5 Torr or less, preferably I
Torr or less, more preferably 0.1 Torr or less.

■Heating temperature The optimum heating temperature is determined depending on the type of thermoplastic resin film and metal plate to be coated, but generally it is higher than the softening point temperature (mp) of the thermoplastic resin film, preferably (mp + 30) °C or higher, more preferably (mp + 50) °C or higher and lower than the thermal decomposition temperature. For polymers, the general temperature is 260~370℃, ethylene
In general, chlorotrifluoroethylene copolymers [
220-350℃, and 25 for polyvinylidene fluoride
0 to 300°C, etc.

■ Heating time The heating time is not something that should be specified in particular, but it must be the time required for at least the surface of the metal plate to reach the heating temperature, and is determined as appropriate depending on the type of metal plate, plate thickness, etc. but generally 1 to 20 minutes, preferably 3 to 1
5 minutes, preferably about 5 to 10 minutes.

(3) Lamination process This process is a process of covering a heated metal plate with a thermoplastic resin film by lamination and pressing.

■ Lamination atmosphere The lamination atmosphere is not particularly limited, but it is desirable that the atmosphere be substantially free of harmful oxygen, at least until the film is laminated and placed on the heated metal plate. The atmosphere is preferably similar to that in the previous step (2) (2).

■ A film laminated and placed on a press-heated metal plate, for example,
This is a process of continuously pressing with a book roll or the like to forcefully cover the paper. Here, the roll in contact with the film is preferably a roll that does not adhere to the film, such as a rubber roll or a metal roll, and the pressing force is 5 to 30 Kz/cd, preferably 10 to 20 Kf/d.

(4) Reheating step This step is a reheating step that is performed as necessary to further strengthen the fusion force between the metal plate and the film of the film-coated metal plate obtained in the previous step.

(2) Heating Atmosphere The heating atmosphere is not particularly limited, and may be in the air, but is preferably an atmosphere similar to the previous step (2), (2).

■ Heating temperature The heating temperature is 1! of the thermoplastic resin film and metal plate to be coated. The optimum temperature is determined depending on the type, but in general, the softening point temperature (mp) of the thermoplastic resin film or higher, preferably (MP+20)°C or higher, more preferably (IP+30)°C or higher, and the thermal decomposition temperature The following is desirable. Specifically, in the case of a fluorine-containing resin film, k amount = t ± = in the case of an ethylene-tetrafluoroethylene copolymer, the temperature is generally 260 to 360°C, ethylene-chlorotrifluoroethylene For copolymers, generally 2
20-350℃ and 200-350℃ for polyvinylidene fluoride
250°C, etc.

■ Heating time The heating time is not something that should be specified in particular; it needs to be the time it takes for at least the surface of the metal plate to reach the heating temperature, and is determined as appropriate depending on the metal plate's Class S and plate thickness. but generally 1 to 20 minutes, preferably 3 to 10 minutes
minutes, more preferably 5 to 7 minutes.

(5) Cooling Step This step is a step of cooling the reheated film-coated metal plate to room temperature, and can be cooled using, for example, an air cooling fan, water, or the like. Here, it is desirable to uniformly cool the plate since distortion and deformation will occur in the plate if the plate is cooled unevenly.

The film-coated metal plate of the present invention obtained through the above steps is heated to fuse and composite the metal plate and thermoplastic resin film in an atmosphere substantially free of oxygen.
The metal plate and thermoplastic resin film are hardly affected by oxidative deterioration, so it is thought that the metal plate and thermoplastic resin film exhibit strong fusion strength and can be used outdoors for a long period of time. . Due to its characteristics, these film-coated metal plates can be used as architectural and construction materials such as roofing materials, exterior wall materials, interior materials and flooring materials, as well as sinks, sinks, etc.
Indoor fixtures such as desks, bookshelves, and furniture, and chemical reaction equipment such as reaction tanks and reaction piping are now widely used in transportation such as automobiles, vehicles, and airplanes, making a huge contribution to industry. It is.

Hereinafter, the present invention will be explained in more detail with reference to examples, but it goes without saying that the present invention is not limited to the examples.

(Preparation of film-coated metal plate) Example 1 Commercially available phosphorus salt-treated electrogalvanized steel plate (Nippon Steel:
Bonded steel plate BGC, thickness 0.8 ~) with an alkaline degreaser (Fine Cleaner 301, manufactured by Nippon Parr Ising)
The surface was washed with water at 60°C for 3 minutes, then washed with water and dried. After placing this steel plate in a nitrogen-substituted heating furnace with an oxygen concentration of 0.1- and heat-treating it at 350°C for 6 minutes,
Using a pair of silicone rolls also placed in a nitrogen atmosphere with the same oxygen concentration, an ethylenetetrafluoroethylene resin film with a thickness of 50 μm was heat-sealed at a pressure of 71 Cy/csf. Furthermore, this heat-sealed steel sheet was reheated at 325°C for 7 minutes in a nitrogen atmosphere, and cooled by leaving it indoors to obtain an ethylenetetrafluoroethylene resin film-coated steel sheet (hereinafter referred to as "metal sheet/metal sheet"). 1).

Example 2 In Example 1, a metal plate was used as a commercially available alloyed hot-dip galvanized steel plate (manufactured by Nisshin Steel: Pentite, thickness 0.5%).
), and after cleaning the surface using an alkaline degreaser, apply a zinc phosphate treatment agent (manufactured by Nippon Parkerizing:
A steel sheet coated with an ethylenetetrafluoroethylene resin film was obtained in the same manner as in Example 1, except that the surface was treated using Parbond-3312 and Parlene 62 (hereinafter referred to as "Metal Plate Todoroki 2").

Example 3 In Example 1, the metal plate was a commercially available hot-dip aluminized steel plate (Nissin Steel Co., Ltd.: Ulster, thickness 0.6%).
), and after cleaning the surface with an alkaline degreaser, apply a chromate-based coating agent (manufactured by Nihon Baru Ising:
A steel plate coated with an ethylenetetrafluoroethylene resin film was obtained in the same manner as in Example 1, except that the surface was treated with Alchrome 713 (hereinafter referred to as "metal plate/ni 3").

Example 4 A steel plate coated with ethylenetetrafluoroethylene 7m fat film was obtained by heat fusion bonding in the same manner as in Example 2 except that the phosphate treatment was not performed. This is called "Metal Sheet 4").

Example 5 Heat fusion was carried out in the same manner as in Example 3 except that the chromate treatment was not carried out to obtain an ethylenetetrafluoroethylene resin film composite steel sheet (hereinafter referred to as "metal"). Board ^ 5").

Example 6 Example 2 In a cloudy oven, a film (thickness 50μ) of tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA) resin was used instead of ethylene-tetrafluoroethylene resin, and the heating temperature was raised to 390°C for 6 minutes. A PF resin film-covered steel plate was obtained in the same manner as in Example 2, except that heat fusion was performed at a reheating temperature of 390° C. for 7 minutes (hereinafter referred to as [metal plate A6J).

Example 7 In Example 2, a vinyl chloride film (manufactured by Nippon Carbide Kogyo ■, high varnish paint, thickness 50μ) was used instead of the ethylenetetrafluoroethylene resin film, the heating temperature was 180°C, and the reheating source was used! A vinyl chloride film-covered steel plate was obtained in the same manner as in Example 2, except that the temperature was 140°C (hereinafter referred to as "metal plate 7").

Example 8 In Example 2, instead of the ethylenetetrafluoroethylene resin film, an acrylic resin film (manufactured by Nippon Carbide Kogyo, Hynis film, thickness 50 μm) was used.
), an acrylic resin film-corroded steel plate was obtained in the same manner as in Example 2, except that the heating temperature was 200°C and the reheating temperature was 170°C (hereinafter referred to as [metal plate A8Jh).

Example 9 In Example 1, the metal plate was a commercially available stainless steel plate (SU
A steel plate coated with an ethylenetetrafluoroethylene resin film was obtained in the same manner as in Example 1, except that 8304, thickness 0.51XI) was used (hereinafter referred to as "metal plate &9").

Example 10 In Example 3, the metal plate was a stainless steel plate (8083
04, to thickness 0.5), the film to I'F person film (
thickness 50μ), heating temperature 390℃, reheating temperature 39
A steel plate coated with a PF film was obtained in the same manner as in Example 3 except that the temperature was 0°C (hereinafter referred to as "metal plate &10").

Example 11 In Example 3, the metal plate was replaced with a commercially available pure aluminum plate (
Alloy number 1100-H14 listed in JI8 H4000
A steel plate coated with an ethylenetetrafluoroethylene resin film was obtained in the same manner as in Example 3, except that a steel sheet (with a thickness of 0.6%) was used (hereinafter referred to as "metal plate A11").
.

Example 12 Example 3 ζ In this case, a metal plate was used as a commercially available (AI-Mg) based metal plate with alloy number 3004 according to JIS H4000.
-θ, thickness 0.6%), the film was PF film (thickness 50μ), the heating temperature was 390℃, and the reheating temperature was 3
A steel sheet coated with a PF film was obtained in the same manner as in Example 3, except that the temperature was 90° C. (hereinafter referred to as "metal sheet 12").

Example 13 In Example 3, the metal plate was a copper plate (rolled copper product, thickness 0.4
%), and before cleaning it with an alkaline degreaser, it was blasted with soft iron powder with an average particle size of 80 mesh to a roughness of 10 to 15μ, and then cleaned with a hydrogen peroxide polishing liquid. A steel plate coated with an ethylenetetrafluoroethylene resin film was obtained in the same manner as in Example 3 (hereinafter referred to as "metal plate 13").

Example 14 A steel plate coated with an ethylenetetrafluoroethylene resin film was obtained in the same manner as in Example 1 except that the oxygen concentration was changed to 0.8 or more.
4).

Comparative Example 1 An ethylenetetrafluoroethylene resin film-coated steel sheet was obtained in the same manner as in Example 2, except that the heating step and subsequent steps were performed in the atmosphere (hereinafter referred to as "metal sheet"). 15).

Comparative Example 2 An ethylenetetrafluoroethylene resin film-coated steel sheet was obtained in the same manner as in Example 9, except that the heating step and subsequent steps were performed in the atmosphere (hereinafter referred to as "metal sheet"). ``Black 16'').

Comparative Example 3 P was produced in the same manner as in Example 12, except that the heating step and subsequent steps were performed in the atmosphere.
An FA film-coated steel plate was obtained (hereinafter referred to as "metal plate 17").
).

Example B (Evaluation of film-coated metal plates) Film-coated metal plates (&1 to 17) prepared by other people were tested and evaluated as follows, and the results are shown in Table 1.

(11th foundation Eriksen test Test and evaluate the adhesion between the film and the metal plate.

■Preparation of test piece■ Cut the metal plates A1 to A17 into sizes of 50x65~, and apply JI8 K5 to the film-covered surface of the test piece.
In accordance with the base grain test method stipulated in 400 (General Test Methods for Paints), 11 orthogonal parallel lines, 11 vertically and horizontally, were drawn using a razor at intervals of IX, and 1ci! 100 in
Form a square.

(2) Of the two test pieces on which the base grains were formed, one piece was left at room temperature, and the other piece was immersed in boiling water for 2 hours, taken out, and dried.

■ Erichsen test (based on J I8 B7729) The test piece prepared in item 0 was squeezed using an Erichsen tester (manufactured by Tokyo Shikenki Seisakusho, Model 18M) under conditions of a punch diameter of 20% and an extrusion depth of 5 or more. Processed.

■ Evaluation method A peel test was performed on the test piece drawn in Section 0 using cloth-based adhesive tape (Surion Tape, manufactured by Yukihara Kogyo).
First, the number of remaining thermoplastic resin films among the 00 substrates was counted, and the adhesion of the films was evaluated.

(2) Film peel strength test Test and evaluate the adhesion between the film and the metal plate.

(2) Preparation of test pieces Each of the black metal plates 1 to 17 was cut into a size of 25 x 150%, and the film about 3 degrees from the end of the test piece was peeled off using a cutter. If the film is difficult to peel off,
The metal is substantially dissolved in an aqueous solution such as 5-ring or 101-hydrocarbon soda to liberate about 3 cx of the film.

(2) Tensile test From the peeled edge of the film obtained in Section 0, turn the film 180' at a film tensile speed of 300±30 w/win, and perform a tensile and peel test.

■ i! If the adhesion between the iF-valent film and the metal is strong, the film will break, in which case it will be displayed as "film cut", and if the film is peeled off, the peeling load (K4/
25m width) was displayed.

Claims (8)

[Claims] (1) A film-coated metal plate characterized in that, when the metal plate is coated with a thermoplastic resin film, at least the heating step of heating the metal plate is performed in an atmosphere substantially free of oxygen. (2) When coating a metal plate with a thermoplastic resin film, at least the heating step of heating the metal plate and the lamination step of laminating the thermoplastic resin film on the heated metal plate are performed in the presence of substantially oxygen. A film-coated metal plate characterized in that it is processed under a non-toxic atmosphere. (3) Claim 1 in which the metal plate is an iron-based metal plate
The film-coated metal plate according to any one of items 1 to 2. (4) The film-coated metal plate according to any one of claims 1 to 2, wherein the thermoplastic resin is a fluorine-containing resin. (5) The film-coated metal plate according to claim 4, wherein the fluorine-containing resin is an ethylene-tetrafluoroethylene copolymer. (6) The film-coated metal plate according to claim 4, wherein the fluorine-containing resin is a perfluoroalkyl vinyl ether-tetrafluoroethylene copolymer. (7) The film-coated metal plate according to any one of claims 1 to 2, wherein the atmosphere is a nitrogen gas atmosphere. (8) A method for producing a film-coated metal plate, characterized in that when coating a metal plate with a thermoplastic resin film, at least the heating step of heating the metal plate is performed in an atmosphere substantially free of oxygen.