JP4805613B2 - Surface-treated metal plate and surface treatment method thereof, and resin-coated metal plate, can and can lid - Google Patents

Description

  The present invention relates to a surface-treated metal plate and a surface treatment method thereof, and more specifically, it is non-chromium and has excellent environmental properties, and adhesion to an organic resin film, adhesion, corrosion resistance, dent resistance, and wear resistance. The present invention relates to a surface-treated metal plate excellent in properties, a surface treatment method for such a surface-treated metal plate, a resin-coated metal plate obtained by resin-coating such a surface-treated metal plate, a metal can and a can lid comprising the same.

As a treatment for improving the adhesion between a metal material such as a steel plate, a zinc-based plated steel plate, an aluminum-based plated steel plate, a zinc alloy plate, a tin-based plated steel plate, an aluminum foil, an aluminum alloy plate, and a magnesium alloy plate, and an organic film, As treatments for joining a metal material to the same or different metal materials using an adhesive, a chromate treatment, a phosphate treatment, a treatment with a silane coupling agent, an anodizing treatment, and the like are conventionally known.
Metal materials using these treatments are widely used for home appliances, building materials, vehicles, aircraft, containers, and the like, and among them, chromate treatment has been most widely used due to its excellent corrosion resistance and adhesion.
Chromate treatment can be broadly classified into treatment methods, and it can be classified into chemical molding (reaction type / coating type) and electrolytic type. It can be classified into a type in which hexavalent chromium remains and a type in which hexavalent chromium does not remain in the final product.

  As for the type in which a small amount of hexavalent chromium remains in the final product, it has been pointed out that it may elute into the environment such as soil at the time of disposal, and the use of chromate treatment is proceeding mainly in Europe. In addition, any type of chromate treatment has various environmental problems because the treatment liquid contains hexavalent chromium which is a harmful substance. That is, it is indispensable to completely drain and exhaust the hexavalent chromium-containing treatment liquid and not to discharge it to the outside, and a large amount of cost is required for drainage and exhaust treatment facilities, disposal costs, and the like. Furthermore, since restrictions on the movement and exhaust of wastewater treatment sludge are becoming stronger, the development of a non-chromium surface treatment comparable to the conventional chromate treatment is desired.

  As a matter of course, a metal plate for a metal container uses a chromate treatment of a type in which hexavalent chromium does not remain in the final product, and is further coated with an organic resin or the like. For example, cathodic electrolysis of a tin-plated steel plate in an aqueous solution of sodium dichromate, cathodic electrolysis treatment of a steel plate in a fluoride-containing chromic anhydride aqueous solution, or treatment of an aluminum alloy with phosphoric acid chromate and an organic resin thereon The one coated with is used.

  As the non-chromium surface treatment of the aluminum alloy metal plate, an acidic treatment solution containing zirconium, titanium, or a compound thereof, phosphate and fluoride and having a pH of about 1.0 to 4.0 is used. In fact, a film formed with a chemical conversion film mainly composed of an oxide of zirconium and / or titanium is actually used, and depending on the compatibility with an organic resin, a film without the chemical conversion film itself has been put into practical use (for example, patents). Reference 1).

  In recent years, a precoat material coated with a polyester resin has been widely used from the viewpoint of hygiene of metal containers and flavor retention of contents. However, when polyester resin is used, it has higher water permeability compared to epoxy phenolic paints and acrylic epoxy paints that have been widely used in the past. Otherwise, the contents may be restricted in terms of adhesion and corrosion resistance. Further, when such a polyester resin coated with aluminum is used as an aluminum lid member, there is a problem that the adhesion is not sufficient even in the chromate treatment.

  In other words, cans and can lids coated with polyester resin, which are examples of processed products of precoat materials, have the advantage that a precoated metal plate can be used as a starting material, but can be highly processed such as can bodies and can lid score parts. Corrosion from the cracked portion of the polyester resin caused by impact such as dropping of the polyester resin at the part or dropping of the can, deterioration of adhesion during retort sterilization, and even if the polyester coating itself is not defective Depending on the component, there are problems different from the conventional manufacturing method in which surface treatment and post-coating of paint are performed after can molding, such as induction of corrosion by permeated ions.

From such a viewpoint, a method of forming an organic-inorganic composite coating containing an organic compound containing carbon as a main component, a phosphorus compound, and a zirconium or titanium compound as a non-chromium surface treatment of an aluminum alloy metal plate (Patent Document 2). ), A method of forming a surface treatment layer mainly composed of an inorganic substance on the surface of an aluminum substrate, and an organic surface treatment layer mainly composed of an aqueous phenol resin thereon (Patent Document 3), and an anode mainly from the viewpoint of a lid material Oxidation treatment
(Patent Documents 4, 5, 6 and 7) are proposed, and other treatments such as a polyacrylic acid-zirconium compound (Patent Document 8 and Non-Patent Document 1) are also proposed.

  On the other hand, most of the non-chromium surface treatment of steel sheets has been proposed mainly for automobile steel sheets and steel sheets for household appliances, such as vanadate coating, tungstate coating, zirconate coating, tannate coating, silicate coating, etc. (Non-Patent Documents 2, 3 and 4) have been studied. Most of the proposals for the non-chromium treatment of steel plates for containers are based on tin-plated steel plates. For example, a steel plate and a resin-coated steel plate provided with a silane coupling agent coating layer after tin plating (Patent Documents 9, 10, 11 and 12), any one of Ti, Mo, V after tin plating, phosphoric acid and / or Alternatively, a film mainly composed of a phosphate-derived substance (Patent Document 13), and a method of forming a composite oxide film of tungsten and tin by subjecting a tinting base material to negative and positive periodic electrolysis in a sodium tungstate solution (non- Patent document 5) etc. are proposed. In addition, it can be applied to both aluminum plates and steel plates, and is a surface-treated metal plate characterized by containing Zr, O, F as a main component and containing no phosphate ions as a non-chromic treatment that can be used for containers (Patent Documents) 14) has been proposed.

JP 52-131937 A JP-A-11-229156 JP 2001-121648 A JP-A-11-91034 JP 2002-266099 A JP 2005-059471 A JP 2005-059472 A Japanese Unexamined Patent Publication No. 06-322552 JP 2002-113809 A JP 2002-285354 A JP 2003-231989 JP 2004-345214 A JP 2001-73185 A JP-A-2005-97712 "Light Metal" (1990) p298-p304 “Material Stage” (2004) VOL.4, No.7 p4-p9 “Material Stage” (2004) VOL.4, No.7 p10-p16 “Material Stage” (2004) VOL.4, No.7 p30-p38 Thin Solid Films, 72, 2, (1980) 237-246

However, in the method of forming an organic-inorganic composite film containing an organic compound mainly composed of carbon, a phosphorus compound, and zirconium or a titanium compound, the adhesion is improved to some extent, but the corrosion resistance is not sufficient, and the surface of the aluminum substrate In the method of forming a surface treatment layer mainly composed of an inorganic substance and an organic surface treatment layer mainly composed of a water-based phenol resin on the surface treatment layer, adhesion and corrosion resistance are improved to some extent. There has been a problem that the waste liquid treatment becomes complicated.
In the method using anodizing treatment, the primary adhesion is good, but the adhesiveness tends to decrease due to the retort sterilization treatment after filling the contents. In addition to the cost of the capacity power source and the like, there is a problem of high cost because a large amount of power is required for processing even during running.
Furthermore, when the thickness of the base material itself, such as an aluminum foil, is thin, the proportion of the anodized film having poor processability and dissolution of the base material during anodization increases, and the flexibility of the foil is reduced. There was a problem.

In the treatment of an aluminum material with a polyacrylic acid-zirconium compound, the coating film to be formed is an organic-inorganic composite coating, and the treatment method is basically a coating type treatment. There is a problem in terms of adhesion.
Furthermore, in many of the above prior arts, the metal plate to be used is limited to an aluminum alloy, and cannot solve the problems of the entire metal material.
In the sense that various materials can be processed, a known method of forming Al ₂ O ₃ , ZrO ₂ or the like on the surface of the metal material by PVD, CVD, or the like can be considered. However, since the above method requires a vacuum, equipment is expensive and high-speed processing is difficult, resulting in a further increase in cost. In addition, it is difficult to ensure adhesion between the metal plate and the treatment film and corrosion resistance after processing. Similarly, in the method of obtaining an oxide film by applying an organic zirconium compound or the like by a wet method and then drying by heating, it is difficult to ensure the adhesion between the metal plate and the treated film and the corrosion resistance after processing.
The surface treatment characterized by containing Zr, O, F as a main component and not containing phosphate ions can be used for both aluminum plates and steel plates, but tin oxide films grow when treated on tin-plated steel plates. There is a problem that the color is likely to change due to aging after treatment and heating.

Therefore, the object of the present invention is a non-chromium surface treatment that is excellent in environmental properties, can be applied to various materials, has excellent discoloration resistance even when used for a tin-plated steel sheet, and has adhesion, adhesion, and corrosion resistance with an organic resin coating. Another object of the present invention is to provide a surface-treated metal plate excellent in various properties such as dent resistance and a surface treatment method for such a surface-treated metal plate.
Another object of the present invention is to provide a low-cost surface treatment method that is easy to manufacture by high-speed treatment from an aqueous solution.
Still another object of the present invention is to provide a metal can and a lid having excellent adhesion, corrosion resistance, dent resistance, and the like comprising a resin-coated metal plate obtained by coating the surface-treated metal plate with an organic resin, particularly a polyester resin. Is to provide.
Another object of the present invention is that the main components of the treatment film are Al and O, and can be used for both iron and aluminum, which are metals that are widely used as structural materials. It is to provide an environmentally friendly treatment method.

According to the present invention, there is provided a metal can comprising a surface-treated metal plate having an inorganic surface treatment layer formed by being deposited on the surface of a metal substrate (excluding Al) by cathodic electrolysis from an aqueous solution, The surface treatment layer is coated with an organic resin on at least one surface of a surface treatment metal plate made of aluminum hydroxide or oxyhydroxide mainly composed of Al and O , and at least one of Zr and Ti. A metal can characterized by comprising a resin-coated metal plate is provided.

According to the present invention, there is also provided a can lid comprising a surface-treated metal plate having an inorganic surface treatment layer formed by being deposited by cathodic electrolysis from an aqueous solution on the surface of a metal substrate (excluding Al), The inorganic surface treatment layer is coated with an organic resin on at least one surface of a surface-treated metal plate made of aluminum hydroxide or oxyhydroxide mainly composed of Al and O, and at least one of Zr and Ti. A can lid comprising a resin-coated metal plate is provided.

In the metal can and can lid of the present invention,
1. The atomic ratio of O and M contained in the outermost surface of the inorganic surface treatment layer (where M is Al or at least one of Al and Ti, Zr) is 1 <O / M <5.5. There is,
2. The atomic ratio of (P + S) and M (wherein M is Al or at least one of Ti and Zr) contained in the outermost surface layer of the inorganic surface treatment layer is (P + S) / M <0. 25,
3. The film thickness of the inorganic surface treatment layer is 5 to 100 mg / m2 by weight of Al. ² Being
4). The metal substrate is a surface-treated steel sheet having a plating layer containing one or more of tin, nickel, zinc, and iron.
5. The surface exposure rate of the main element of the metal substrate is less than 5%,
6). On the inorganic surface treatment layer, 0.8 to 30 mg / m as Si amount ² An organic surface treatment layer mainly composed of a silane coupling agent of
7). An organic surface treatment layer mainly composed of a phenol-based water-soluble organic compound is formed on the inorganic surface treatment layer.
8). The outermost layer of the organic surface treatment layer contains N,
Is preferred.
In the present invention, Al represents aluminum, O represents oxygen, F represents fluorine, Zr represents zirconium, Ti represents titanium, P represents phosphorus, and S represents sulfur.

According to the present invention, there is provided a metal can comprising a surface-treated metal plate having an inorganic surface treatment layer formed by being deposited on the surface of a metal substrate (excluding Al) by cathodic electrolysis from an aqueous solution, The surface treatment layer is made of at least one of aluminum hydroxide or oxyhydroxide mainly composed of Al and O , and Zr, Ti, so that high-speed productivity, environmental conservation, scratch resistance, adhesion It is possible to provide a surface-treated metal plate excellent in workability and adhesion at low cost, and a metal can is formed from a metal plate coated with an organic resin, particularly a polyester resin, on the surface-treated metal plate. In this way, excellent adhesion and corrosion resistance can be obtained even in highly processed parts, and a can lid is formed from a metal plate coated with organic resin, especially polyester resin, on this surface-treated metal plate. The Rukoto excellent openability even after heat sterilization can be obtained.

Moreover, in this invention, it can apply also to surface treatment steel plates, such as a tin plating steel plate and a galvanization steel plate, in addition to an aluminum plate and a steel plate, for example, zinc and tin by applying to a galvanization steel plate and a tin plating steel plate. It is possible to provide a surface-treated steel sheet that can be applied to a wider range of applications by being able to obtain a synergistic effect between the anti-corrosion property and the adhesion and corrosion resistance of non-chromium surface treatment, and by being able to treat various substrates. . Moreover, even if it treats a tin plating steel plate like the inorganic surface treatment layer which has Zr, O, and F as a main component and does not contain phosphoric acid, a tin oxide film grows, and time and heat after the treatment Therefore, it is possible to obtain a metal plate and a metal can that have the above-mentioned properties and can be used as a can lid.
In addition, by using the same surface treatment, problems such as galvanic corrosion often reported when using a combination of dissimilar metal plates such as aluminum and steel (for example, a combination of an aluminum lid and a steel can body in a metal can). Can also be avoided.
In the surface-treated metal plate and the resin-coated metal plate of the present invention, it can be effectively used particularly for metal cans and can lids, but can also be used effectively for applications such as automobiles, home appliances, and building materials. .

In the surface-treated metal plate of the present invention, it is an important feature that the inorganic surface-treated layer formed on the surface of the metal plate (excluding aluminum) contains at least Al and O.
A surface-treated metal plate having a surface-treated layer formed by cathodic electrolysis from an aqueous solution on the surface of a metal substrate, the inorganic surface-treated layer containing Al, O and F, and having an inorganic surface The atomic ratio of F and M contained in the outermost surface of the treatment layer (where M is Al or Al and at least one of Ti and Zr) is 0.1 <F / M Is an important feature.
As a result, as described above, various metal materials can be subjected to surface treatment.
In the surface-treated metal plate of the present invention, the inorganic surface-treated layer contains F in addition to Al and O, so that the surface of the treated layer is maintained in a stable state even in a high-temperature and high-humidity environment. As a result, it is possible to maintain the corrosion resistance and suppress the decrease in the adhesion or adhesiveness of the resin film. In addition, in the manufacturing process, the presence of an appropriate amount of F is effective for producing a uniform inorganic coating, and as a result, 0.1 <F / M of F is included in the coating component. In particular, in the case of an aluminum substrate, since a film is easily formed locally, it is important that the inorganic film contains F of 0.1 <F / M.

That is, when the inorganic surface treatment layer contains Al and O as main components and does not contain F, the structure of the treatment film is expected to be a structure such as AlO _X (OH) _Y.
However, the hydroxyl group may be hydrated in a high-temperature and high-humidity environment to induce structural changes in the treatment layer and adversely affect various properties. By including an appropriate amount of F, at least a part of the hydroxyl group is substituted with F, and a stabilizing structure such as AlO _X (OH) _YZ F _{Z is formed} , so that the treatment layer in a high temperature and high humidity environment can be obtained. It is possible to suppress structural changes and maintain a more stable surface.

In the present invention, when the inorganic surface treatment layer is used alone, it is important to control the amount of anions of the inorganic surface treatment layer, particularly phosphate ions and sulfate ions. As a result, even when subjected to retort sterilization or storage over time under high-temperature and high-humidity conditions, elution of anions from the treated film is effectively suppressed, and the adhesion or adhesiveness of the resin film may be reduced. It is effectively prevented.
In the chemical conversion treatment and anodizing treatment, which are conventional metal plate surface treatment methods, sulfate ions and phosphate ions are easily contained in the film due to the film formation mechanism, and the chemical conversion treatment is a constituent component. It is known that anions with large ionic radii such as anions in these membranes, particularly phosphate ions, are likely to elute under high temperature and high humidity such as retort sterilization treatment. Adhesiveness and adhesiveness of the resin film provided on the surface-treated metal plate are lowered.

  In the present invention, when the outermost surface of the inorganic surface treatment layer is analyzed by X-ray photoelectron spectroscopy (XPS) described later, peaks such as N1s, F1s, S1s, P1s may be detected. This means the presence of anionic components such as nitric acid, fluorine, sulfuric acid and phosphoric acid. From the analysis results, it is known that phosphate ions and sulfate ions are easily taken into the film components, and in particular, phosphoric acid is likely to be present in large quantities. Therefore, when preparing the treatment bath, it is desirable to take care such as reducing the proportion of phosphate chemicals and mixing with other chemicals. Thus, in the present invention, by controlling phosphate ions and sulfate ions, which are anions with a large ionic radius, even when subjected to retort sterilization or storage over time under high temperature and high humidity conditions, Since the elution of anions from the treated film is effectively suppressed, the adhesion or adhesiveness of the resin film is effectively prevented from decreasing.

In the surface-treated metal plate of the present invention, an organic surface treatment layer mainly composed of a phenol-based water-soluble organic compound or a silane having an Si amount of 0.8 to 30 mg / m ² on the inorganic surface treatment layer. It is also important that a coupling agent treatment layer is formed.
While the inorganic surface treatment layer described above mainly contributes to the corrosion resistance of the metal plate, the organic surface treatment layer mainly contributes to adhesion with an organic coating such as a polyester resin. By laminating in order, even when subjected to high-level processing, it is possible to exhibit excellent processing adhesion and corrosion resistance with the organic resin coating.

  Particularly in metal cans or can lids prepared from the surface-treated metal plate of the present invention and a resin-coated metal plate obtained by coating the surface-treated metal plate with an organic resin, in particular, a polyester resin, excellent work adhesion and corrosion resistance were obtained. Since the resin-coated metal plate is used, the processing adhesion of the polyester resin film at the high-processed part, the corrosion resistance (dent resistance) from the cracked part of the polyester resin film caused by impact, and the retort sterilization It is possible to improve the adhesiveness of the open lid, and the corrosion due to the amount of permeated ions is suppressed, and the openability of the easy open can lid can be improved.

The most remarkable effect of molding a resin-coated metal plate with a polyester film on the silane coupling agent layer or phenolic organic surface treatment layer formed on the metal plate surface is In the heat setting step, a re-adhesion effect is obtained by the silane coupling agent layer and the phenolic organic surface treatment layer being reconstituted with polyester. That is, although the adhesion at the polyester-metal interface is reduced by molding, the silane coupling agent layer and the phenolic organic surface treatment layer are compatible with the polyester without heating to the melting point of the polyester or higher in the heat setting process. This will restore the adhesion. It is important that these organic surface treatment layers exist together with the inorganic surface treatment layer, and if there is no inorganic surface treatment layer, it is difficult to suppress the metal substrate surface change during retort, It is not preferable from the viewpoint of not only adhesion but also corrosion resistance.
As described above, when an organic surface treatment layer mainly composed of a phenol-based water-soluble organic compound or a silane coupling agent treatment layer is formed, the organic surface treatment layer is coated with an organic coating such as a polyester resin. Due to the adhesion effect and the effect of recovery of adhesion by heat setting after processing, it is possible to use anion having a large ionic radius under high temperature and high humidity. However, as a matter of course, it is the most desirable usage form that the inorganic surface treatment layer does not contain anions having a large ion radius such as sulfate ions and phosphate ions.

Furthermore, in the surface treatment method for a metal plate of the present invention, cathodic electrolysis is performed in an aqueous solution having an Al ion concentration in the range of 0.001 to 0.05 mol / liter, and more preferably F ions are contained in the aqueous solution. It is an important feature to include.
According to cathodic electrolysis, the film formation rate is faster than the reactive chemical conversion coating, the film thickness control range can be greatly expanded, and the coating can be generated according to the application. is there.
On the other hand, in the conventional chemical conversion treatment, the film formation rate is limited because it depends on the chemical reaction depending on the composition of the treatment solution. For this reason, the film thickness is limited in the high-speed treatment, whereas the cathode electrolytic treatment. Then, since an electrolytic reaction is utilized, high-speed processing of film formation becomes possible.
In addition, in the chemical conversion treatment and anodizing treatment, sulfate ions and phosphate ions are easily contained in the film due to the film formation mechanism, and the chemical conversion treatment becomes a constituent component, so it is difficult to control the amount of anion as described above. is there.

On the other hand, according to the cathodic electrolytic treatment, various aqueous solutions can be selected, and an aqueous solution of fluoride or nitrate can be used. Therefore, a large ionic radius such as sulfate ion or phosphate ion can be obtained. It is possible to form a film in which the amount of anion is controlled.
In addition, in the chemical conversion treatment and the anodizing treatment, the base metal element that is the material to be treated is easily contained in the film due to the film formation mechanism, and in the reactive chemical conversion treatment, it becomes a constituent component. The composition needs to be examined and in some cases drastically changed. On the other hand, according to the cathodic electrolysis treatment, the change of the bath composition can be kept to a minimum, and since the range that can be adjusted according to the electrolysis conditions is wide, it is possible to treat various substrates.

  In the surface treatment method for a metal plate of the present invention, the uniformity of the film thickness is improved by electrolyzing while stirring a bath, in particular, air bubbles containing oxygen at 20 to 300 ml / min · cm on the cathode surface. A uniform precipitation state can be obtained over the entire surface. That is, by performing electrolysis while blowing bubbles containing oxygen on the cathode surface, local concentration polarization is suppressed, and at the same time, the O / Al ratio of the surface treatment layer is controlled by the bubbles containing oxygen to achieve high quality and uniform treatment. Is possible.

(Surface-treated metal plate)
<Inorganic surface treatment layer>
In the surface-treated metal sheet of the present invention, as described above, one important characteristic is that the inorganic surface-treated layer of the surface-treated metal sheet contains at least Al and O, and more preferably further contains F. is there.
In the inorganic surface treatment 1 containing Al and O by cathodic electrolysis according to the present invention shown in FIG. 1, an O1s peak 11, an Al2p peak 12 and an F1s peak 13 are measured by an X-ray photoelectron spectrometer (hereinafter referred to as XPS). An example was given. Here, the case where F is included as a component of the inorganic surface treatment layer in addition to Al and O is shown.

Further, in the surface-treated metal plate of the present invention, it is another important feature that it contains aluminum hydroxide or oxyhydroxide.
Hereinafter, the inorganic surface treatment layer according to the present invention contains aluminum hydroxide or oxyhydroxide with examples. First, O1s, Al2p, and C1s due to contamination of the sample are measured by XPS on the outermost surface of the inorganic surface treatment layer, and binding energy positions 111 and 112 of O1s and Al2p are obtained as shown in FIG. Next, the binding energy positions 111 and 121 of O1s and Al2p are corrected so that the binding energy position of C1s due to the contamination of the sample is constant among the samples to be compared, and the normal binding energy position is obtained. Here, since the absolute value of the binding energy differs depending on the apparatus, it is important to compare the energy positions of the samples in the same apparatus.

According to the above method, a sample in which tin was plated on a steel sheet after 1.3 g / m ² plating, and an inorganic surface treatment layer was formed on the surface with an Al weight film thickness of 30, 40, and 80 mg / m ² , and a comparative material As described above, the binding energy positions of O1s and Al2p were determined for the samples of the alumina sintered body and the aluminum rolled sheet. Of these, Al 40 mg / m ² samples were cathodic electrolyzed using an aluminum nitrate bath and the others using an aluminum sulfate bath. The alumina sintered body as a comparative material is Al ₂ O ₃ and the surface of the aluminum rolled plate is also considered to be aluminum oxide. It used for the measurement after heat processing for 1 hour. The results are shown in Table 1. Here, the binding energy position has been corrected using the C1s peak due to contamination of the sample. As shown in Table 1, the material of the present invention is higher in O1s by 0.1 to 0.8 eV and Al2p by 0.4 to 1.0 eV in comparison with the comparative material. It can be seen that the material contains hydroxide or oxyhydroxide instead of oxide.

Further, the surface-treated metal sheet of the present invention, the inorganic O and M contained in the outermost surface of the surface treatment layer (where, M is a A l, Ti, among the at least one or more kinds of Zr) atomic ratio of It is an important feature that 1 <O / M <5.5, more preferably 1 <O / M <3.5. It is difficult to form an inorganic surface treatment film smaller than the above range and having an O / M of 1 or less.
In the case where an anion component having a large ionic radius is hardly contained, O of O / M is in the range of 1 <O / M <2.5. In the case of 2.5 ≦ O / M <3.5, the coating contains a slight amount of anionic components such as phosphoric acid and sulfuric acid having a large ionic radius, and 3.5 ≦ O / M <5. .5, it is considered that a considerable amount of anion component is contained. Therefore, in the case of 3.5 ≦ O / M <5.5, an organic surface treatment layer such as a coupling agent treatment layer is provided on the inorganic surface treatment layer in order to ensure adhesion after retorting. It is desirable. Furthermore, when it exceeds the said range and it is 5.5 <O / M, it is thought that base-material components other than the element contained in said M are also oxidizing. In other words, the tin layer on the surface of the tinplate is oxidized, resulting in an increase in O / M. In this case, since the tin surface itself is oxidized, the cohesive force is weak, and even if an organic surface treatment layer is provided, sufficient adhesion cannot be obtained.

Furthermore, in the surface-treated metal plate of the present invention, F and M contained in the outermost surface of the inorganic surface-treated layer of the surface-treated metal plate (where M is Al or at least one of Al, Ti and Zr). Is preferably less than 2.5, particularly 2.0 or less.
When F / M is 2.5 or more, although F has a small ionic radius, the amount of anions with respect to M becomes excessive, causing a decrease in adhesion.

For measuring the atomic ratio of O / M and F / M, the peak present on the surface such as C1s, O1s, F1s, Al2p, Ti3d, Zr3d is measured by XPS, and the atomic concentration is obtained by analysis software. Can be obtained from
If the surface-treated metal plate used for measurement is in a clean state, the surface is analyzed as it is. After the organic resin is bonded or fused, it is necessary to first remove the organic resin layer by immersing it in a boiled hydrogen peroxide solution for several minutes.
Samples that are not clean and samples after removal of the organic resin coating layer described above, when the sum of the main constituent elements of the surface such as C, O, F, Al, Zr, Ti, and base metal elements is 100%, The contaminated layer is lightly removed by Ar sputtering until the atomic concentration of C1s becomes 10% or less, and the atomic ratios of O / M and F / M at this point can be obtained. Further, after obtaining the peak area after background removal for each element of O, F and Al, Zr, and Ti by an ordinary method, the atomic concentration of each element is obtained using the relative sensitivity coefficient of the measuring device, and O / M And the F / M ratio may be obtained by calculation.
FIG. 2 shows an example of the Al2p peak 2. A range surrounded by the reference line 21 and the peak 22 of the background is a peak area 23. Needless to say, since the atomic ratio varies depending on how the background is drawn, attention should be paid to how the background is drawn.

In the present invention, the most desirable form of the inorganic surface treatment layer is that the coating does not contain an anion component having a large ionic radius such as phosphoric acid or sulfuric acid, as described above. The atomic ratio of (P + S) and M (where M is Al or Al and at least one of Ti and Zr) contained in the outermost layer of the inorganic surface treatment layer is (P + S) / M < It is a feature of the present invention that 0.25, more preferably (P + S) / M <0.05.
FIG. 3 compares the S1s peak 31 on the outermost surface of the anodized alumite with sulfuric acid and the S1s peak 32 on the outermost surface of the inorganic surface treatment layer according to the present invention by XPS. Similarly, the P2p peak and the peak existing on the surface such as C1s, O1s, F1s, Al2p, Ti3d, Zr3d existing on the surface are respectively measured, and (P + S) / M is obtained from the value obtained by the analysis software. be able to. In the sample used in the example of FIG. 3, the value of (P + S) / M was 0.0 in the present invention, whereas it was 0.1 in the anodized alumite.

Moreover, as a film thickness, it is preferable that it is between 5-100 mg / m < ² > by the weight film thickness of Al. If it is less than 5 mg / m ^2, it is difficult to produce a uniform film, and the coverage is not sufficient. If it exceeds 100 mg / m ² , the adhesiveness is lowered by processing, which is not preferable.
As a measuring method of the weight film thickness, when the main component of the substrate metal is other than Al, the film thickness can be quantified by a commercially available fluorescent X-ray analyzer. In this case, a calibration curve showing the relationship between the Al weight film thickness and the Al X-ray intensity is prepared in advance from a plurality of samples with known Al weight film thickness, and then the X-ray intensity of Al measured using an unknown sample. Is converted into a weight film thickness based on a calibration curve.
When the main component of the substrate metal is Al, the base metal is dissolved with an acid or the like, the inorganic surface treatment layer is extracted, and the X-ray intensity is measured by the energy dispersive X-ray analyzer attached to the transmission electron microscope. Measured by a method for obtaining a weight film thickness from a relationship between a calibration curve prepared using a standard sample.
When the inorganic surface treatment layer contains at least one of Zr and Ti in addition to Al, the density of each element is different, so that the total weight film thickness of Al, Zr and Ti is 5 to 300 mg / m ^2. It is preferable to be between.

In the present invention, when a surface treatment is performed on a metal substrate having a plating layer, the surface exposure rate of the main element of the metal substrate is preferably less than 5%, and preferably less than 3%.
If the exposure rate of the metal base main element is more than this, satisfactory performance cannot be obtained in corrosion resistance and adhesion. In particular, when processing on the surface where metallic tin is present, such as tinplate, thin tin-plated steel sheet, and ultrathin tin-plated steel sheet, if the tin surface exposure rate is 5% or more, in addition to corrosion resistance and adhesion, Problems of sulfurity and discoloration over time also occur, and the appearance is inferior. The surface exposure rate is a value obtained by measuring the peak of major elements existing on the surface such as C1s, P2p, O1s, F1s, S1s, Al2p, Ti3d, Zr3d, Sn3d5, Fe2p by XPS, and obtaining the atomic concentration by analysis software. Can be obtained from However, since the Fe2p peak may overlap with the Sn peak, in this case, it is necessary to perform peak separation.

<Silane coupling agent treatment layer>
In the surface-treated metal plate of the present invention, it is particularly preferable that a silane coupling agent-treated layer having an Si amount of 0.8 to 30 mg / m ² is further formed on the inorganic surface-treated layer.
The silane coupling agent that forms the silane coupling agent treatment layer has a reactive group that chemically bonds to the thermoplastic polyester resin and a reactive group that chemically bonds to the inorganic surface treatment layer, and includes an amino group, an epoxy group, and a methacryloxy group. , Which are composed of organosilanes containing a reactive group such as a mercapto group and a hydrolyzable alkoxy group such as a methoxy group or an ethoxy group, or a hydrolyzable organic substituent such as a methyl group, a phenyl group, an epoxy group or a mercapto group Silanes containing alkoxy groups can be used.

Specific examples of silane coupling agents that can be suitably used in the present invention include γ-APS (γ-aminopropyltrimethoxysilane), γ-GPS (γ-glycidoxypropyltrimethoxysilane), BTSPA ( Bistrimethoxysilylpropylaminosilane), N-β (aminoethyl) γ-aminopropyltrimethoxysilane, and the like.
The silane coupling agent-treated layer is preferably formed so that the Si amount is 0.8 to 30 mg / m ² , particularly 3 to 15 mg / m ² . If the amount of Si is less than the above range, the effect of the organic surface treatment layer, that is, the effect of improving corrosion resistance and adhesion is poor, and if the amount of Si is more than the above range, the unreacted silane coupling agent is self-condensing. Therefore, satisfactory work adhesion and corrosion resistance cannot be obtained.
The silane coupling agent treatment layer can also be formed on an inorganic surface treatment layer containing SiO ₂ particles.

(Layer mainly composed of phenolic water-soluble organic compounds)
In the surface-treated metal sheet of the present invention, it is particularly preferable that a layer mainly composed of a phenol-based water-soluble organic compound exists on the inorganic surface-treated layer.
As a phenol type water-soluble organic compound, following formula (1)
OH
｜
− Φ −CH ₂ − (1)
｜
X
In the formula, φ represents a benzene ring, X represents a hydrogen atom or the following formula (2)
Z = —CH ₂ —N—R ₁ (2)
｜
R ₂
In the formula, each of R ₁ and R ₂ represents Z represented by: an alkyl group having 10 or less carbon atoms, an alkyl group having 10 or less carbon atoms, or a hydroxyalkyl group having 10 or less carbon atoms; The rate shall be 0.2-1.0 per benzene ring,
It is preferable that it is a phenol resin which consists of a repeating unit represented by these.

Another example of the phenolic water-soluble organic compound is tannin. Tannin, also called tannic acid, is a general term for aromatic compounds having a complex structure having a phenolic hydroxyl group.
Examples of tannins include hameli tannins, oyster tannins, chatannins, pentaploid tannins, gallic tannins, milovalan tannins, dibidi tannins, argarovira tannins, valonia tannins, catechin tannins and the like. Tannin preferably has a number average molecular weight of 200 or more.
In the organic surface treatment layer mainly composed of the above-mentioned phenol-based water-soluble organic compound, the organic surface treatment layer has a phenol content of ^{3 to} 75 mg / m ² , particularly 6 to 30 mg / m ^{2 in} terms of carbon atoms. It is desirable to contain a water-soluble organic compound. When the amount is less than the above range, the adhesion of the organic surface treatment film is inferior. On the other hand, when the amount is more than the above range, the film thickness of the organic surface treatment film becomes larger than necessary and the adhesion and corrosion resistance are lowered. The organic surface treatment layer mainly composed of the phenol-based water-soluble organic compound is an organic-inorganic formed by using an organic compound mainly composed of carbon and a surface treatment agent containing a phosphorus compound and zirconium or a titanium compound. It may be a composite layer.

Furthermore, in the surface-treated metal plate on which the organic surface treatment layer of the present invention is formed, it is preferable that the outermost layer contains N.
FIG. 4 shows the results of measuring the N1s peak 41 by XPS for the outermost layer of the surface-treated metal plate having a silane coupling agent layer on the surface. As shown in FIG. 4, N is detected, and N is also detected in the phenolic water-soluble organic compound.

FIG. 5 thru | or FIG. 7 is sectional drawing which shows an example of the surface treatment metal plate of this invention, respectively. The surface-treated metal plate 5 shown in FIG. 5 has a metal plate substrate 51 and an inorganic surface treatment layer 52 provided on the surface of the substrate and mainly composed of Al and O. In the example of FIG. 6, an organic surface treatment layer 53 mainly composed of an organic component is formed on the inorganic surface treatment layer 52 of FIG.
The surface-treated metal plate 5 shown in FIG. 7 is the same as that in FIG. 5 in that it has an inorganic surface-treated layer 52 containing Al and O as main components, but the metal plate base 51 is made of a metal plate 51a and a metal. It is constituted by a plating layer 51b. As the metal plating layer 51b covered with the metal plate 51a occupying most of the base 51, a layer having a role of enhancing the corrosion resistance of the metal plate 51a is used as will be described later.

(Metal plate base)
As the metal plate substrate used in the present invention, various surface-treated steel plates and light metal plates such as aluminum are used. As the surface-treated steel sheet, a cold-rolled steel sheet is annealed and then secondary cold-rolled, and galvanized, tin-plated, nickel-plated, aluminum-plated, or the like can be used as a surface-treated steel sheet. In addition, an aluminum clad steel plate or the like can also be used.
Moreover, the said plating layer may consist only of the metal layer containing 1 or more types of tin, nickel, zinc, iron, and aluminum, and the said plating layer is 1 type of tin, nickel, zinc, iron, and aluminum. It may consist of a metal layer containing the above and an alloy layer containing two or more of tin, nickel, zinc, aluminum and iron, or the plating layer is made of tin, nickel, zinc, iron or aluminum. You may consist only of the alloy layer containing 2 or more types.

  The metal formed by plating or cladding on the surface side of the metal plate base is attached for the purpose of improving various properties such as the corrosion resistance, wear resistance, and electrical conductivity of the metal located on the center side. Specifically, it is almost always given for the purpose of improving the corrosion resistance. In addition to so-called pure aluminum, an aluminum alloy is used as the light metal plate. The original thickness of the metal plate is not particularly limited, and varies depending on the type of metal and the use or size of the container. However, the metal plate generally has a thickness of 0.10 to 0.50 mm. In the case of a treated steel plate, the thickness may be 0.10 to 0.30 mm, and in the case of a light metal plate, the thickness may be 0.15 to 0.40 mm.

(Surface treatment method)
In the metal plate surface treatment method of the present invention, it is an important feature that the cathode electrolytic treatment is performed in an aqueous solution having an Al ion concentration in the range of 0.001 to 0.05 mol / liter. In the cathodic electrolysis treatment, if a local electrolytic concentration occurs, a non-uniform film is formed, so care must be taken to ensure a uniform potential distribution. In particular, the treatment on a metal plate having a dense oxide film formed on the surface or the treatment on a metal plate that is easily dissolved in an acidic region is likely to cause local electrolytic concentration, and it is difficult to form a uniform film. For this reason, for example, when processing an aluminum plate, a special pretreatment such as a zincate treatment is often required.
In the present invention, electrolytic treatment is performed in a low-concentration bath in order to produce a surface treatment film that is as uniform as possible without performing a special pretreatment. That is, if the bath concentration is higher than the above range, concentration polarization is likely to occur, and electrolysis concentrates preferentially in a portion having low polarization resistance, resulting in an undesirable formation of a non-uniform film. On the other hand, when the bath concentration is lower than the above range, the electrical conductivity of the bath is low, which causes an increase in power required for the treatment, which is not preferable.

In the surface treatment method of the present invention, it is preferable that F ions are further contained in the aqueous solution in addition to the Al ions.
FIG. 8 shows a comparison of the deposited film thickness of Al by electrolysis under the same conditions using a bath containing no F ions and a bath containing 0.024 mol / liter of F ions using a tin-plated steel sheet as a cathode. . The horizontal axis indicates the total electrolysis time which is the sum of the energization time and the stop time when intermittent electrolysis is performed by repeating the energization and stop cycles a plurality of times. As is apparent from the figure, it is understood that the formation rate of the Al film is faster when F ions are included.

Further, in the surface treatment method of the present invention, since it depends on the bath concentration, the bath composition, and the material of the base material, it is not possible to limit the clear current density range, but in general, it is as high as about 5 A / dm ² or more. In terms of current density, it is preferable to perform cathodic electrolysis intermittently, that is, to perform intermittent electrolysis in which a stop time is provided during electrolysis and electrolysis is performed by repeating a cycle of energization and stop in the stirred aqueous solution a plurality of times. When electrolysis is performed continuously, a loose film having a large O / Al ratio is deposited in a gel form on the cathode surface, resulting in concentration polarization and inhibiting the formation of a good quality film. On the other hand, by intermittently electrolyzing, ions such as Al, O, OH, and F are supplied to the vicinity of the cathode due to the stirring effect during the electrolysis stop, and a loose film generated at the cathode, that is, A film having a large O / Al ratio is removed by stirring, and as a result, a film having a higher Al weight film thickness is formed and a higher quality film is provided.

The energization and stop cycle is not limited to this, but the energization time is 0.1 to 0.8 seconds and the stop time is 0.3 to 1.5 seconds. Is preferred.
On the other hand, when electrolysis is performed at a low current density, for example, about 0.5 A / dm ² , there is no difference in deposition efficiency between continuous electrolysis and intermittent electrolysis, or continuous electrolysis is more efficient. Precipitate. In the case of a low current density, since the deposition rate is slow and concentration polarization is less likely to occur, there is no difference between continuous electrolysis and intermittent electrolysis, or conversely, continuous electrolysis has a higher deposition efficiency.

The aqueous solution used for the surface treatment is preferably an aqueous solution having a pH of 2.0 to 7.0, more preferably a pH of 2.3 to 6.0. As an Al agent used for the treatment liquid, aluminum nitrate Al (NO ₃ ) ₃・ In addition to 9H ₂ O, aluminum potassium sulfate AlK (SO ₄ ) ₂ · 12H ₂ O, aluminum sulfate Al ₂ (SO ₄ ) ₃ · 13H ₂ O, aluminum dihydrogen phosphate Al (H ₂ PO ₄ ) ₃ , Aluminum dihydrogen phosphate AlPO ₄ , aluminum lactate [CH ₃ CH (OH) COO] ₃ Al, and the like can be used.
Also, when using a Zr or Ti with Al, zirconium fluoride potassium KZrF ₆ and fluoride ammonium zirconium as Zr drug _{(NH 4)} 2 ZrF _6, zirconium ammonium carbonate solution _{(NH 4) 2 ZrO (CO} 3) 2 , Zirconium oxynitrate ZrO (NO ₃ ) ₂ , zirconium oxyacetate ZrO (CH ₃ COO) _{2, and the} like can be used. As the Ti agent, potassium titanium fluoride K ₂ TiF ₆ , ammonium titanium fluoride (NH ₄ ) ₂ TiF ₆ , Titanium fluoride sodium Na ₂ TiF ₆
Further, potassium potassium oxalate dihydrate K ₂ TiO (C ₂ O ₄ ) ₂ · 2H ₂ O, titanium chloride (III) solution TiCl ₃ , titanium chloride (IV) solution TiCl _{4 and the} like can be used.

As the fluoride ion agent, sodium fluoride NaF, potassium fluoride KF, ammonium fluoride NH ₄ F, or the like can be used.
Even in the case of using Al agent without containing Zr or Ti agent, it is preferable from the viewpoint of the precipitation efficiency that F is contained in the aqueous solution, but particularly when Zr or Ti agent is used together with Al, It is preferable that F is contained in the aqueous solution in the range of 0.03 mol / liter to 0.35 mol / liter. If the fluorine ion concentration is lower than the above range, the deposition efficiency is low and, in addition, the surface becomes unstable over time in a high temperature and high humidity environment. This is not preferable because it tends to inhibit efficiency and tends to cause precipitation in the bath.

Furthermore, nitrate ions, peroxides, and complexing agents may be added to the aqueous solution used for the surface treatment, if necessary.
Nitrate ions have the effect of maintaining the stability of the deposited state during electrolysis over a long period of time, and nitric acid, sodium nitrate, potassium nitrate, ammonium nitrate, and the like can be used as an ion source. The peroxide has an effect of generating oxygen in an aqueous solution and suppressing concentration polarization near the cathode surface, and is particularly useful when the bath is poorly stirred. As the peroxide, for example, hydrogen peroxide, ammonium peroxodisulfate, potassium peroxodisulfate, sodium peroxoborate, sodium peroxocarbonate, sodium peroxodisulfate and the like can be used. Furthermore, the complexing agent has a function of suppressing the formation of precipitates in the bath, such as ethylenediaminetetraacetic acid, ethylenediaminetetraacetic acid sodium, citric acid, sodium citrate, boric acid, nitrilotriacetic acid, nitrilotriacetic acid sodium, Cyclohexanediaminetetraacetic acid, glycine, or the like can be used. If the concentration of nitrate ion, peroxide, and complexing agent is too high, the precipitation efficiency tends to be inhibited. The concentration of nitrate ion, peroxide, and complexing agent is 0.2 mol / liter. The following is preferable.

As a pretreatment of the metal plate substrate, degreasing, washing with water, if necessary, pickling, washing with water, cleaning the surface, and stirring the aqueous solution at a temperature of 10 to 65 ° C., When the current density is about 5 to 50 A / dm ² , the total electrolysis time is 0.3 by the intermittent electrolysis method in which the cycle of energization and stop is repeated, or when the current density is about 0.1 to 5 A / dm ² by the continuous electrolysis method. A suitable surface structure can be obtained by cathodic electrolysis for ˜60 seconds and finally washing with water. The current density range is not limited because it depends on the ease of concentration polarization. That is, the current density range of whether intermittent electrolysis is preferable or continuous electrolysis is different depending on the bath concentration, the bath composition, the material of the base material, and the like. It is preferable to perform intermittent electrolysis at a high current density and continuous electrolysis at a low current density when the bath concentration is low.
As the counter electrode plate corresponding to the anode side, a titanium plate coated with iridium oxide is preferably used. As a condition of the counter electrode plate, it is desirable that the counter electrode material is an insoluble anode having a small oxygen overvoltage without being dissolved in the treatment liquid during electrolysis.

In the surface treatment method of the present invention, it is particularly preferable to form an organic coating by applying a phenol-based water-soluble organic compound or a silane coupling agent after forming the inorganic coating and drying it.
In order to form the organic coating on the inorganic surface treatment layer, the above-described phenol-based water-soluble organic compound or silane coupling agent solution is applied on the inorganic surface treatment layer, or the phenol-based water-soluble organic compound or silane coupling agent solution. It can be formed by immersing the surface-treated metal plate on which the inorganic surface-treated layer is formed, removing the excess solution with a squeeze roll, and then drying by heating under a temperature condition of 80 to 180 ° C. it can.

(Resin coated metal plate)
The resin-coated metal plate of the present invention is formed by coating a layer made of an organic resin, particularly a polyester resin, on at least one surface of the surface-treated metal plate. Therefore, it has excellent corrosion resistance and dent resistance.
In FIG. 9 showing a cross-sectional view of an example of the resin-coated metal plate of the present invention, this resin-coated metal plate 5 is formed on the metal plate substrate 51 and the substrate surface when viewed from the inner surface side (right side in the figure) when used as a container. A multilayer of an inorganic surface treatment layer 52 having Al and O as main components, an organic surface treatment layer 53 provided on the inorganic surface treatment layer 52, and a polyester resin coating layer 54 provided thereon. It has a structure. In the example of FIG. 9, an outer surface resin protective layer 55 is provided on the outer surface side (left side in the figure) of the container via the inorganic surface treatment layer 52, and the outer surface resin protective layer 55 is formed of the polyester resin. Even if it is the same polyester resin as the coating layer 54, it may consist of a different polyester resin, and may consist of a different resin.

  Further, in FIG. 10 showing another example of the resin-coated metal plate, the resin-coated metal plate 5 was applied to the surface of the surface treatment layer 52 containing Al and O as main components and the inner surface of the base 51. Although the organic surface treatment layer 53, the polyester resin layer 54, and the outer surface resin protective layer 55 provided on the outer surface side are the same as those in FIG. 9, the base 51 is formed of a metal plate 51a and a metal plate. The polyester resin layer 54 has a laminated structure of a polyester resin surface layer 54a and a polyester resin lower layer 54b. As described above, the metal plating layer 51b covered with the metal plate 51a occupying most of the base 51 is used to increase the corrosion resistance of the metal plate 51a. As described above, the polyester resin lower layer 54b is excellent in adhesion to a metal substrate, while the polyester resin surface layer 54a is excellent in content resistance.

(Organic resin coating layer)
In the resin-coated metal plate of the present invention, the organic resin provided on the metal plate is not particularly limited, and examples thereof include various thermoplastic resins and thermosetting or thermoplastic resins.
As the organic resin, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic ester copolymer, olefin resin film such as ionomer, or polyester film such as polybutylene terephthalate, or A non-stretched or biaxially stretched thermoplastic resin film such as a nylon film such as nylon 6, nylon 6, 6, nylon 11 or nylon 12, a polyvinyl chloride film or a polyvinylidene chloride film may be used. When an adhesive is used in the lamination, a urethane adhesive, an epoxy adhesive, an acid-modified olefin resin adhesive, a copolyamide adhesive, a copolyester adhesive (thickness: 0.1 to 5. 0 μm) is preferably used. Further, a thermosetting paint may be applied to the surface-treated metal plate side or film side in a thickness range of 0.05 to 2 μm, and this may be used as an adhesive.

Further, as organic resins, modified epoxy paints such as phenol epoxy and amino-epoxy, vinyl chloride-vinyl acetate copolymer, saponified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer , Epoxy-modified-, epoxy-amino-modified, epoxy-phenol-modified-vinyl paint or modified vinyl paint, acrylic paint, thermoplastic or thermosetting paint such as synthetic rubber paint such as styrene-butadiene copolymer alone or 2 It may be a combination of more than one species.
Among these, a polyester resin is most preferably used as a container material. Examples of the polyester resin include thermoplastic polyesters derived from an alcohol component mainly composed of ethylene glycol or butylene glycol and an acid component such as an aromatic dibasic acid such as terephthalic acid, isophthalic acid, or naphthalenedicarboxylic acid.
Of course, polyethylene terephthalate itself can be used as the polyester, but lowering the maximum crystallinity that the film can reach is desirable in terms of impact resistance and processability. It is preferable to introduce the copolymerized ester unit. It is particularly preferable to use a copolyester having a melting point of 210 to 252 ° C. mainly composed of ethylene terephthalate units or butylene terephthalate units and containing a small amount of other ester units. The melting point of homopolyethylene terephthalate is generally 255 to 265 ° C.

In general, 70 mol% or more, particularly 75 mol% or more of the dibasic acid component in the copolyester is composed of a terephthalic acid component, and 70 mol% or more, particularly 75 mol% or more of the diol component is composed of ethylene glycol or butylene glycol, It is preferable that 1 to 30 mol%, particularly 5 to 25 mol% of the dibasic acid component is composed of a dibasic acid component other than terephthalic acid.
Dibasic acids other than terephthalic acid include aromatic dicarboxylic acids such as isophthalic acid, phthalic acid and naphthalenedicarboxylic acid: alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid: succinic acid, adipic acid, sebacic acid, dodecanedioic acid, etc. Or a combination of two or more of the aliphatic dicarboxylic acids: As the diol component other than ethylene glycol or butylene glycol, propylene glycol, diethylene glycol, 1,6-hexylene glycol, cyclohexane dimethanol, bisphenol A 1 type, or 2 or more types, such as an ethylene oxide adduct. Of course, the combination of these comonomers is preferably such that the melting point of the copolyester falls within the above range.

Further, the polyester may contain at least one branching or crosslinking component selected from the group consisting of a tribasic or higher polybasic acid and a polyhydric alcohol in order to improve the melt flow characteristics during molding. . These branching or crosslinking components should be in the range of 3.0 mol% or less, preferably 0.05 to 3.0 mol%.
Examples of the trifunctional or higher polybasic acid and polyhydric alcohol include trimellitic acid, pyromellitic acid, hemimellitic acid, 1,1,2,2-ethanetetracarboxylic acid, 1,1,2-ethanetricarboxylic acid, 1 , 3,5-pentanetricarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, polybasic acids such as biphenyl-3,4,3 ′, 4′-tetracarboxylic acid, pentaerythritol, glycerol, Examples include polyhydric alcohols such as trimethylolpropane, 1,2,6-hexanetriol, sorbitol, 1,1,4,4-tetrakis (hydroxymethyl) cyclohexane.

In the resin-coated metal plate of the present invention, as a particularly suitable polyester resin that can be used for a can-making or lid-making material, polyethylene terephthalate / isophthalate containing 5 to 25 mol% of isophthalic acid component, 1 cyclohexanedimethanol component Examples thereof include polyethylene / cyclohexylene dimethylene terephthalate containing 10 to 10 mol%.
The homopolyester or copolyester should have a molecular weight in the film forming range, and the intrinsic viscosity [η] measured using a phenol / tetrachloroethane mixed solvent as the solvent is 0.5 to 1.5, especially 0. It may be in the range of 6 to 1.5.

  The polyester resin layer used in the present invention may be formed from the above-described polyester or copolyester alone, or a blend of two or more of polyester or copolyester, or a blend of polyester or copolyester and another thermoplastic resin. It may be formed from an object. Examples of blends of two or more of polyester or copolyester include polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate / isophthalate, and combinations of two or more of polyethylene / cyclohexylene dimethylene terephthalate. It is not limited to.

Examples of other thermoplastic resins that can be blended in the polyester include ethylene polymers, thermoplastic elastomers, polyarylate, and polycarbonate. At least one of these modified resin components can be further contained to further improve high-temperature wet heat resistance and impact resistance. This modified resin component is generally used in an amount of up to 50 parts by weight, particularly preferably 5 to 35 parts by weight, per 100 parts by weight of polyester.
Examples of the ethylene polymer include low-, medium- or high-density polyethylene, linear low density polyethylene, linear ultra-low density polyethylene, ethylene-propylene copolymer, ethylene-butene-1 copolymer, ethylene- Examples include propylene-butene-1 copolymer, ethylene-vinyl acetate copolymer, ion-crosslinked olefin copolymer (ionomer), and ethylene-acrylic acid ester copolymer. Among these, ionomers are preferable, and as the base polymer of ionomer, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester- (meth) acrylic acid copolymer, ion As the seed, Na, K, Zn or the like is used. Examples of the thermoplastic elastomer include a styrene-butadiene-styrene block copolymer, a styrene-isoprene-styrene block copolymer, a hydrogenated styrene-butadiene-styrene block copolymer, and a hydrogenated styrene-isoprene-styrene block copolymer. Etc. are used.

Polyarylate is defined as a polyester derived from a dihydric phenol and a dibasic acid. As the dihydric phenol, 2,2′-bis (4-hydroxyphenyl) propane (bisphenol A), 2 , 2′-bis (4-hydroxyphenyl) butane (bisphenol B), 1,1′-bis (4-hydroxyphenyl) ethane, bis (4-hydroxyphenyl) methane (bisphenol F), 4-hydroxyphenyl ether, p- (4-hydroxy) phenol or the like is used, and bisphenol A and bisphenol B are preferred. As the dibasic acid, terephthalic acid, isophthalic acid, 2,2- (4-carboxyphenyl) propane, 4,4′-dicarboxydiphenyl ether, 4,4′-dicarboxybenzophenone, or the like is used. The polyarylate may be a homopolymer derived from the monomer component or a copolymer.
Further, it may be a copolymer of ester units derived from an aliphatic glycol and a dibasic acid as long as the essence is not impaired. These polyarylates are available as Unitika U polymer U series or AX series, UCC Ardel D-100, Bayer APE, Hoechst Durel, DuPont Arylon, Kaneka Chemical NAP resin, etc. it can.

  Polycarbonate is a carbonate resin derived from bicyclic dihydric phenols and phosgene, and is characterized by having a high glass transition point and heat resistance. Examples of the polycarbonate include bisphenols such as 2,2′-bis (4-hydroxyphenyl) propane (bisphenol A), 2,2′-bis (4-hydroxyphenyl) butane (bisphenol B), 1,1′- Bis (4-hydroxyphenyl) ethane, bis (4-hydroxyphenyl) methane (bisphenol F), 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) cyclopentane, , 1-bis (4-hydroxyphenyl) -1-phenylmethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,2-bis (4-hydroxyphenyl) ethane, etc. Polycarbonate is preferred.

The polyester resin layer used in the present invention may be a single resin layer or a multilayer resin layer formed by coextrusion or the like. When a multilayer polyester resin layer is used, a polyester resin having an excellent adhesive property is selected for the base layer, that is, the surface-treated metal plate side, and the surface layer is resistant to contents, that is, extraction resistance and non-adsorption of flavor components. This is advantageous because a polyester resin having an excellent composition can be selected.
Examples of multilayer polyester resin layers are shown as surface layer / lower layer, polyethylene terephthalate / polyethylene terephthalate / isophthalate, polyethylene terephthalate / polyethylene / cyclohexylene dimethylene / terephthalate, polyethylene terephthalate / isolated with low isophthalate content. Polyethylene terephthalate / isophthalate having a high phthalate / isophthalate content, polyethylene terephthalate / isophthalate / [blend of polyethylene terephthalate / isophthalate and polybutylene terephthalate / adipate] and the like are of course not limited thereto. The surface layer: lower layer thickness ratio is preferably in the range of 5:95 to 95: 5.

In the polyester resin layer, known compounding agents for resins, for example, antiblocking agents such as amorphous silica, inorganic fillers, various antistatic agents, lubricants, antioxidants, ultraviolet absorbers, etc., according to known formulations Can be blended.
Of these, tocopherol (vitamin E) is preferably used. Tocopherol is conventionally known as an antioxidant that prevents molecular weight reduction due to degradation during heat treatment of a polyester resin and improves dent resistance. When this tocopherol is blended with a polyester composition blended as a modified resin component, not only the dent resistance, but also when the film is cracked due to severe conditions such as retort sterilization and hot bender, It is possible to prevent the corrosion from proceeding from the cracks and to obtain the effect that the corrosion resistance is remarkably improved.
Tocopherol is preferably blended in an amount of 0.05 to 3% by weight, particularly 0.1 to 2% by weight.

  In the present invention, the thickness of the organic resin layer is generally in the range of 3 to 50 μm, particularly 5 to 40 μm. That is, when the thickness is less than the above range, the corrosion resistance becomes insufficient, and when the thickness exceeds the above range, a problem is likely to occur in terms of workability.

(Manufacture of resin-coated metal plates)
In the present invention, the polyester coating layer can be formed on the surface-treated metal plate by any means, for example, extrusion coating, cast film thermal bonding, biaxially stretched film thermal bonding, or the like. . In the case of the extrusion coating method, it can be produced by extrusion coating a polyester resin in a molten state on a surface-treated metal plate and thermally bonding it. That is, after melt-kneading the polyester resin with an extruder, it is extruded from a T-die into a thin film, and the extruded molten resin film is passed through a pair of laminating rolls together with a surface-treated metal plate to be pressed and integrated under cooling, Then quench rapidly. When extrusion coating a multilayer polyester resin layer, an extruder for surface layer resin and an extruder for lower layer resin are used, and the resin flow from each extruder is merged in a multiple multilayer die, and thereafter a single layer Extrusion coating may be performed as in the case of resin. Further, by passing a surface-treated metal plate vertically between a pair of laminate rolls and supplying a molten resin web on both sides thereof, a polyester resin coating layer can be formed on both sides of the substrate.

  The production of the resin-coated metal plate by the extrusion coating method is specifically performed as follows. A surface-treated metal plate (hereinafter also referred to simply as a metal plate) is preheated by a heating device as necessary, and is supplied to a nip position between a pair of laminate rolls. On the other hand, the polyester resin is extruded into the form of a thin film through a die head of an extruder, supplied between the laminate roll and the metal plate, and pressed onto the metal plate by the laminate roll. The laminating roll is maintained at a constant temperature, and a thin film made of a thermoplastic resin such as polyester is pressure-bonded to the metal plate to thermally bond them together, and cooled from both sides to obtain a resin-coated metal plate. In general, the formed resin-coated metal plate is further led to a cooling water tank or the like to perform rapid cooling in order to prevent thermal crystallization.

  In this extrusion coating method, the polyester resin layer has a low crystallinity level and the difference from the amorphous density is suppressed to 0.05 g / cm 3 or less by selection of the resin composition and rapid cooling by a roll or a cooling bath. Therefore, sufficient workability with respect to can manufacturing, lid processing, etc. performed next is guaranteed. Of course, the rapid cooling operation is not limited to the above example, and the laminate plate can be rapidly cooled by spraying cooling water onto the resin-coated metal plate to be formed.

The thermal adhesion of the polyester resin to the metal plate is performed by the amount of heat that the molten resin layer has and the amount of heat that the metal plate has. The heating temperature (T1) of the metal plate is generally 90 ° C. to 290 ° C., particularly 100 ° C. to 280 ° C., while the laminating roll temperature is suitably 10 ° C. to 150 ° C.
The resin-coated metal plate of the present invention can also be produced by thermally bonding a polyester resin film previously formed by a T-die method or an inflation film forming method to the metal plate. As the film, an unstretched film obtained by a cast molding method in which the extruded film is rapidly cooled can be used, and this film is sequentially or simultaneously biaxially stretched at a stretching temperature to heat-fix the stretched film. It is also possible to use a biaxially stretched film produced by the above method.

  In the present invention, various configurations other than the above-described layer configuration can be adopted, and in the case of forming an organic surface treatment layer, it is not particularly necessary. It is of course possible to provide a primer. This adhesion primer exhibits excellent adhesion to both the metal material and the film. Primer paints with excellent adhesion and corrosion resistance are phenol epoxy paints composed of resol type phenol aldehyde resins derived from various phenols and formaldehyde and bisphenol type epoxy resins, especially phenol resins and epoxy. It is a paint containing a resin in a weight ratio of 50:50 to 1:99, in particular 40:60 to 5:95. The adhesive primer layer is generally preferably provided with a thickness of 0.01 to 10 μm. The adhesion primer layer may be provided in advance on a metal material, or may be provided on a polyester film.

(Metal can and its manufacturing method)
As long as the metal can of this invention is formed from the resin-coated metal plate mentioned above, it may be based on arbitrary can manufacturing methods. The metal can can be a three-piece can having a side seam, but is generally preferably a seamless can (two-piece can). This seamless can is drawn and re-squeezed, bent and stretched by drawing and re-drawing (stretching), and bent and drawn by drawing and re-drawing so that the polyester resin coating surface of the surface-treated metal plate is on the inside of the can. -It is manufactured by attaching to a conventionally known means such as ironing or drawing / ironing. Further, the seamless can may be a two-piece can used by tightening the lid after neck formation, or a bottle-type can used by capping after multi-stage neck processing and screw processing. In the case of a bottle-type can, a three-piece type can in which a shell lid is wound around the bottom and capping is performed on the top of the can.

  In FIG. 11 which shows the seamless can which is an example of the metal can of this invention, this seamless can 111 is formed by the drawing and ironing of the resin-coated metal plate described above, and includes a bottom portion 112 and a body portion 113. Yes. The bottom part 112 and the trunk | drum 113 are connected seamlessly. The bottom 112 has substantially the same thickness configuration as the resin-coated metal plate used at the center, but at least a part of the body 113 is thinned to 30% to 70% of the original plate thickness. Has been. A flange portion 115 for winding with a can lid is formed on the upper portion of the body portion 113 via a neck portion 114 having one or more stages.

As described above, the manufacture of this seamless can is performed by drawing and ironing. However, as this method, the drawing and ironing may be performed simultaneously with one stroke or another stroke. You can do it separately.
For example, in a preferred method for manufacturing a seamless can, a resin-coated metal plate is sheared into a circle, and a shallow drawing cup is formed by drawing using a combination of a drawing die and a drawing punch, and then drawn in the same mold. Simultaneously squeezing and ironing while repeating ironing is repeated several times to form a cup with a small diameter and a large height. In this molding method, deformation for thinning is performed in this order by a combination of deformation due to a load in the can axis direction (height direction) (bending and stretching) and deformation due to a load in the can thickness direction (squeezing). This has the advantage that the molecular orientation in the can axis direction is effectively imparted. After that, a can is produced by performing doming molding, heat treatment for the purpose of removing residual distortion of the coating resin generated by processing, and subsequently performing trimming processing of the end of the opening, curved surface printing, neck-in processing, and flange processing.
Of course, a known can-making method can be applied to the production of the metal can of the present invention. For example, the drawing and ironing method described in JP-A-4-231120, or JP-A-9-253772. It is possible to apply the simultaneous drawing and ironing method described in the above.

(Can lid and its manufacturing method)
The can lid of the present invention may be formed by any conventionally known lid-making method as long as it is formed from the resin-coated metal plate described above. In general, the present invention can be applied to a stay-on-tab type easy open can lid and a full open type easy open can lid.
In FIG. 12 showing the upper surface of the easy open can lid of the present invention and FIG. 13 showing an enlarged cross section, the lid 60 is formed of the resin-coated metal plate described above and is fitted to the inner surface of the can body side surface. A sealing groove 62 is provided on the outer peripheral side via a power annular rim portion (counter sink) 61, and a score 64 formed over the entire circumference defining a portion 63 to be opened is provided inside the annular rim portion 61. Is provided. Inside the portion 63 to be opened, there is a substantially semicircular recess panel 65 formed by pushing a substantially central portion, a dimple 66 formed by protruding a cover material around the recess panel 65 and the cover material. A rivet 67 formed so as to protrude toward the outer surface of the lid is formed, and an opening tab 68 is fixed by riveting the rivet 67. The opening tab 68 has an opening tip 69 by pushing and tearing at one end and a holding ring 70 at the other end. In the vicinity of the rivet 67, on the opposite side of the score 64, a breaking start score 71 is formed in parallel with the score 64.

When opening, the ring 70 of the opening tab 68 is held and lifted upward. As a result, the breaking start score 71 is broken, the opening tip 69 of the opening tab 68 is pushed relatively large downward, and a part of the score 64 starts to be sheared.
Next, by pulling the ring 70 upward, the remaining portion of the score 64 is broken over the entire circumference, and opening is easily performed.
The lid of the above specific example is a so-called full open type, but it can of course be applied to a stay-on-tab type easy open lid.
In a suitable manufacturing method of an easy open can lid, a resin-coated metal plate is punched into a circular shape by a press molding process and formed into a lid shape. Create an easy open can lid by engraving the score so that it reaches the middle of the metal material from the outer surface side of the lid, then forming the rivet, attaching the tab to the rivet, then attaching the tab by hitting the rivet To do. A suitable example of an easy open can lid is described in, for example, Japanese Patent Application Laid-Open No. 2000-128168.

Next, an Example and a comparative example are shown, this invention is demonstrated concretely, and an effect is clarified.
Since the metal container is placed in the most severe environment in terms of workability and corrosion resistance of the surface-treated metal material or resin-coated metal material, the examples are shown by metal cans and can lids. However, the present invention is not limited to the examples.

The concentration of aluminum ion, titanium ion, zirconium ion and fluorine ion was adjusted to be an aqueous solution having a molar concentration shown in Table 2 as Al, Ti, Zr and F, respectively. However, aluminum nitrate Al (NO ₃ ) ₃ · 9H ₂ O is used for the treatment baths A, B, C, D, E, F, J, K, L, M, N, and O as the aluminum chemicals, and the treatment bath G is used. Uses aluminum sulfate Al ₂ (SO ₄ ) ₃ · 13H ₂ O, treatment bath H uses aluminum dihydrogen phosphate solution Al (H ₂ PO ₄ ) ₃ , and treatment bath I uses a molar ratio of diphosphate 2 to hydrogen aluminum solution _Al (H 2 _{PO 4) 3} is 2, were mixed at a ratio of aluminum nitrate aluminum dihydrogenphosphate solution _{Al (H 2 PO 4) 3} Al (NO 3) 3 · 9H 2 O 8 Drugs were used. Further, zirconium zirconium fluoride (NH ₄ ) ₂ ZrF ₆ was used for the treatment baths J and L as the zirconium agent, and ammonium titanium fluoride (NH ₄ ) ₂ TiF ₆ was used for the treatment baths K and L as the titanium agent. In addition, as the fluorine source, sodium fluoride NaF is used for the treatment baths B, D, F, I, and M, ammonium fluoride NH ₄ F is used for the treatment baths E and O, and the treatment baths B and D are used for the treatment baths B and D. As a buffer, boric acid H ₃ BO ₃ was used.

[Production of polyester film]
A polyester film having a composition shown in Table 3 is melt-extruded from two extruders via a two-layer T die, and then cooled with a cooling roll, and a film obtained by cooling the film is shown in Table 4. B), (b), (c), (d), (e), (f), (g).

[Measurement of surface atomic ratio and surface exposure rate]
The surface of the metal material after the surface treatment was measured with an X-ray photoelectron spectrometer (XPS) under the following conditions, and the peaks of major elements existing on the surface such as C1s, O1s, F1s, Al2p, Ti3d, Zr3 were measured and obtained by analysis software. The atomic ratio of O / M, F / M, (P + S) / M (where M includes Al, or Al and at least one of Ti and Zr) was determined from the atomic concentration. However, when calculating the atomic ratio, the atomic concentration when the contaminated layer was lightly removed by Ar sputtering until the atomic concentration of C1s became 10% or less was used. As for the surface exposure rate, for example, when the substrate metal is a tin-plated steel plate, the peak of main elements existing on the surface such as C1s, P2p, O1s, F1s, S1s, Al2p, Ti3d, Zr3d, Sn3d5, Fe2p, etc. Each surface was measured and the atomic concentration of tin determined by analysis software was defined as the surface exposure rate.
Equipment PHI Quantum 2000
Excitation X-ray source Al monochromator 75W-17kV
Measurement diameter φ100μm
Photoelectron extraction angle 90 ° (0 ° with respect to sample normal)
Analysis software; MultiPak

<Evaluation of steel>
[Adhesion evaluation]
The surface-treated metal material was cut into a strip shape having a width of 5 mm and a length of 80 mm, and the cast film shown in Table 4 (g) was cut into a strip shape having a width of 5 mm and a length of 80 mm. The polyester film section was sandwiched between the obtained two surface-treated strip sections and heated at 220 ° C. for 3 seconds under a pressure of 2.0 kg / cm ² to obtain a T peel test piece. Thereafter, a retort treatment was performed at 110 ° C. for 60 minutes, and the film was immersed in water immediately after the completion, pulled up from the water just before measurement by a tensile tester, and measured for adhesive strength at a tensile speed of 10 mm / min.

[Evaluation of corrosion resistance]
After the surface-treated metal material was cut into a strip shape having a width of 70 mm and a length of 150 mm, the cut portion of 3 mm width was protected with a tape, and the state of occurrence of iron rust after spraying with an aqueous 35% NaCl solution for 6 hours was observed.

[Sulfur resistance evaluation]
The surface-treated metal material was cut into 70 mm square, and then 3 mm overhang processing was performed with an Erichsen tester. Next, the 3 mm width of the cut portion was protected with a tape, and 4.5 g / liter of potassium dihydrogen phosphate KH ₂ PO ₄ and 12 g / liter of sodium hydrogen phosphate Na ₂ HPO ₄ · 12H ₂ O
And a retort treatment at 115 ° C. for 60 minutes in a sealed container.

[Discoloration evaluation]
The surface-treated metal material was cut into 70 mm square and heated at 200 ° C. for 1 hour, and the degree of discoloration after heating was compared.

(Example 1)
1. Preparation of surface-treated metal plate Cold-rolled steel sheet having a thickness of 0.195 mm and a tempering degree T3 as a metal plate is subjected to electrolytic degreasing, acid washing, water washing, pure water washing, pretreatment, and 1.3 g / m tin per side. After plating to ² , reflow treatment is performed, and then the iridium oxide-coated titanium plate disposed at a distance of 17 mm between the electrodes is used as an anode while stirring in the treatment bath of A in Table 2 at a bath temperature of 45 ° C. Cathodic electrolysis was performed at a current density of 2 A / dm ² for 12 seconds, and immediately thereafter, washing with running water, washing with pure water, and drying were performed.

2. Evaluation of surface-treated metal plate A part of the obtained surface-treated metal plate was subjected to weight film thickness measurement such as Al, Ti, Zr, surface atomic ratio measurement, surface exposure rate measurement, corrosion resistance evaluation, and adhesion evaluation. The results are shown in Table 5.
In the table, the evaluation of adhesiveness is that the maximum tensile strength after peeling the test piece by 10 mm or more with a tensile testing machine is 0.6 kg / 5 mm or more, ◎, 0.3 kg / 5 mm or more and less than 0.6 kg / 5 mm ◯, 0.2 kg / 5 mm or more and less than 0.3 kg / 5 mm, △, and less than 0.2 kg / 5 mm.
In addition, the evaluation of corrosion resistance is ◎ when rust is hardly generated, ◯ when rust is slightly recognized, △ when rust is 10% or more and less than 20% of surface area, rust is 20% or more of surface area Those present were evaluated as x.
Further, in the evaluation of the sulfur resistance, the case where the processed part was not discolored was evaluated as ◎, the case where the discolored part of the processed part was less than 25% in the area ratio was evaluated as ◯, and the case where the discoloration was higher was evaluated as ×.
Further, the evaluation of discoloration was evaluated visually. A sample having almost no discoloration and a discoloration portion having an area ratio of less than 20% were evaluated as ◯, and a discoloration of 20% or more was evaluated as ×.

(Example 2)
Cathodic electrolysis is intermittently performed by repeating 0.6 sec energization-0.4 sec stop eight times with a tin plating amount of 5.6 g / m ² and a current density of 2 A / dm ^{2 in} the treatment bath of Table 2B. Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained.

(Example 3)
Evaluation was performed in the same manner as in Example 1 except that the surface treatment metal plate was obtained by performing cathodic electrolysis for 24 seconds at a current density of 1 A / dm ² in the treatment bath of Table 2C.

(Example 4)
An inorganic surface treatment layer was formed in the same manner as in Example 3 except that the amount of tin plating was 0.4 g / m ² and an alloy layer was formed by reflowing so that there was no free tin on the surface. Evaluation was performed in the same manner as above.

(Example 5)
Evaluation was performed in the same manner as in Example 1 except that the surface treatment metal plate was obtained by performing cathodic electrolysis at a current density of 1 A / dm ² for 12 seconds in the treatment bath of Table 2B.

(Example 6)
The amount of tin plating is 0.4 g / m ² , an alloy layer is formed by reflow, free tin is present on the surface, and cathodic electrolysis is carried out for 4 seconds at a current density of 1 A / dm ² in the treatment bath of B in Table 2. Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained.

(Example 7)
The tin plating amount was set to 2.8 g / m ² , the current density was set to 1.2 A / dm ^{2 in} the treatment bath of Table 2B, and 0.6 seconds energization—0.4 seconds stop was repeated 16 times intermittently. Evaluation was performed in the same manner as in Example 1 except that the surface-treated metal plate was obtained by performing cathodic electrolysis.

(Example 8)
Except that the surface treatment metal plate was obtained by performing cathodic electrolysis at a current density of 1 A / dm ² for 4 seconds in the treatment bath of D in Table 2 without performing reflow treatment with the same tin plating amount as in Example 1. Evaluation was performed in the same manner as in Example 1.

Example 9
Cathodic electrolysis is performed intermittently by repeating 0.6 sec energization-0.4 sec stop 6 times with a tin plating amount of 0.9 g / m ² and a current density of 1 A / dm ^{2 in} the treatment bath E in Table 2 Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained.

(Example 10)
Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained by performing cathodic electrolysis at a current density of 1 A / dm ² for 8 seconds in the treatment bath F shown in Table 2.

(Example 11)
Except that the current density was 2 A / dm ^{2 in} the treatment bath G in Table 2 and the surface-treated metal plate was obtained by repeating cathodic electrolysis intermittently by repeating 0.6 second energization-0.4 second stop eight times. Evaluation was performed in the same manner as in Example 1.

Example 12
Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained by performing cathodic electrolysis in a H treatment bath of Table 2 at a current density of 2 A / dm ² for 24 seconds.

(Example 13)
Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained by performing cathodic electrolysis for 8 seconds at a current density of 1 A / dm ² in the treatment bath I in Table 2.

(Example 14)
Cathodic electrolysis is intermittently conducted by repeating 0.6 sec energization-0.4 sec stop eight times with a tin plating amount of 0.7 g / m ² and a current density of 1 A / dm ^{2 in} the treatment bath J in Table 2. Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained.

(Example 15)
The amount of tin plating was set to 2.8 g / m ^2, and a surface-treated metal plate was obtained by performing cathodic electrolysis for 8 seconds at a current density of 2 A / dm ² in the treatment bath of K in Table 2 without performing reflow treatment. Were evaluated in the same manner as in Example 1.

(Example 16)
Except for obtaining a surface-treated metal plate by intermittently performing cathodic electrolysis by repeating 16 times energization of 0.6 seconds-stop of 0.4 seconds as a current density of 2 A / dm ^{2 in} the treatment bath of L in Table 2. Evaluation was performed in the same manner as in Example 1.

(Example 17)
Evaluation was performed in the same manner as in Example 1 except that the surface-treated metal plate was obtained by performing cathodic electrolysis for 8 seconds at a current density of 2 A / dm ² in the M treatment bath of Table 2.

(Example 18)
Cathodic electrolysis is performed intermittently by repeating 0.6 sec energization-0.4 sec stop four times with a tin plating amount of 11.2 g / m ² and a current density of 1 A / dm ^{2 in} the treatment bath E in Table 2 Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained.

(Comparative Example 1)
Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained by performing cathodic electrolysis for 16 seconds at a current density of 1 A / dm ² in the treatment bath F shown in Table 2.

(Comparative Example 2)
The tin plating amount is 0.4 g / ^{m 2,} to form an alloy layer by reflowing, and the absence free tin on the surface, as a current density of 2A / dm ² in the processing bath H of Table 2, 0.6 Evaluation was performed in the same manner as in Example 1 except that the surface treatment metal plate was obtained by intermittently performing cathodic electrolysis by repeating the second energization-stop for 0.4 seconds four times.

(Comparative Example 3)
Evaluation was performed in the same manner as in Example 1 except that a surface-treated metal plate was obtained by performing cathodic electrolysis for 4 seconds at a current density of 2 A / dm ² in the H treatment bath of Table 2.

(Comparative Example 4)
The amount of tin plating is 0.4 g / m ² , an alloy layer is formed by reflow, and there is no free tin on the surface. The current density is 2 A / dm ^{2 in} the O treatment bath of Table 2, and 0.6 Evaluation was performed in the same manner as in Example 1 except that the surface treatment metal plate was obtained by intermittently performing cathodic electrolysis by repeating the second energization-stop for 0.4 seconds four times.

(Comparative Example 5)
Except that the amount of tin plating was 2.8 g / m ² , cathode electrolysis treatment was performed in a sodium dichromate aqueous solution, and a surface-treated metal plate was obtained by chromium-based surface treatment with an oxide chromium amount of 3 mg / m ² by a conventional method. According to Example 1, performance evaluation was performed.

(Comparative Example 6)
Except that a cathodic electrolytic treatment was carried out in an aqueous solution of chromic anhydride and sulfuric acid, and a surface-treated metal plate was obtained by a chromium-based surface treatment with a metal chromium content of 7 mg / m ² and an oxide chromium content of 12 mg / m ^{2 according to} a conventional method. Performance evaluation was performed according to Example 1.

(Comparative Example 7)
In the same manner as in Example 1, tin plating and reflow treatment were performed, and the current density was set to 0.7 A / dm ² in an aqueous solution composed of 0.025 mol / liter of zirconium zirconium fluoride and 0.005 mol / liter of potassium nitrate. The surface-treated metal plate was obtained by repeating cathodic electrolysis intermittently by repeating energization for 6 seconds and stopping for 0.4 seconds four times. Since the discoloration after aging was severe, no evaluation other than discoloration was performed.

(Example 19)
1. Preparation of surface treatment agent mainly composed of phenolic water-soluble organic compound The following was used as a surface treatment agent mainly composed of a phenolic water-soluble organic compound.
Hydrofluoric acid (HF)
0.01 g / liter 75% phosphoric acid (H ₃ PO ₄ )
0.20 g / liter 20% zirconium hydrofluoric acid (H ₂ ZrF ₆ ) 1.30 g / liter Water-soluble polymer solid content of the following formula (I)
The following formula (I) used as an example of a water-soluble polymer is shown below at 0.40 g / liter.

OH
｜
-Φ-CH _2- (I)
｜
X
In the formula, X is a hydrogen atom or a Z group represented by the following formula (II), and an aqueous phenol resin consisting of repeating units in which the Z group is introduced at a ratio of 0.3 per benzene ring Z = —CH _{2 -N-CH} 2 CH 2 OH
｜
CH ₂ CH ₂ OH (II)
The water-soluble polymer which consists of a repeating unit represented by these.

2. Preparation and evaluation of surface-treated metal plate On the inorganic surface-treated layer prepared in Example 1, the surface treatment agent mainly composed of the phenol-based water-soluble organic compound prepared in 1 above was sprayed at 40 ° C. for 20 seconds and then washed with water. Then, it was washed with pure water to obtain a surface-treated metal plate having an organic surface treatment layer on the inorganic surface treatment layer. Thereafter, evaluation of adhesiveness, corrosion resistance and sulfur resistance was performed in the same manner as in Example 1, and the results are shown in Table 6.

(Example 20)
Treatment and evaluation were performed in the same manner as in Example 19 except that a phenol-based water-soluble organic compound layer was formed on the inorganic surface treatment layer created in Example 2. Further, when XPS analysis of the surface before and after the organic surface treatment was performed, the N1s peak that was not present before the organic surface treatment was confirmed.

(Example 21)
The treatment and evaluation were carried out in the same manner as in Example 19 except that a phenol-based water-soluble organic compound layer was formed on the inorganic surface treatment layer created in Example 9.

(Example 22)
On the inorganic surface-treated layer prepared in Example 1, it was dipped in a 3% aqueous solution of γ-aminopropyltrimethoxysilane (product name KBM903, manufactured by Shin-Etsu Chemical Co., Ltd.), squeezed and dried at 120 ° C. for 1 minute. A surface-treated metal plate having a silane coupling agent layer corresponding to a film thickness of 5 mg / m ^{2 in} terms of Si on the inorganic treatment layer was obtained. Thereafter, evaluation was performed in the same manner as in Example 19.

(Example 23)
The treatment and evaluation were carried out in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer created in Example 2. Further, when XPS analysis of the surface before and after the organic surface treatment was performed, the N1s peak that was not present before the organic surface treatment was confirmed.

(Example 24)
The treatment and evaluation were carried out in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer created in Example 6.

(Example 25)
The treatment and evaluation were performed in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer created in Example 11. Further, when XPS analysis of the surface before and after the organic surface treatment was performed, the N1s peak that was not present before the organic surface treatment was confirmed.

(Example 26)
The treatment and evaluation were carried out in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer created in Example 12.

(Example 27)
Treatment and evaluation were performed in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer prepared in Comparative Example 1.

(Example 28)
Treatment and evaluation were performed in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer created in Comparative Example 2.

(Example 29)
Treatment and evaluation were performed in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer prepared in Comparative Example 3.

(Example 30)
Treatment and evaluation were performed in the same manner as in Example 22 except that a silane coupling agent layer was formed on the inorganic surface treatment layer created in Comparative Example 4.

(Comparative Example 8)
On the inorganic surface-treated layer prepared in Example 1, it was dipped in a 30% aqueous solution of γ-aminopropyltrimethoxysilane (product name KBM903, manufactured by Shin-Etsu Chemical Co., Ltd.), squeezed and dried at 120 ° C. for 1 minute. A surface-treated metal plate having a silane coupling agent layer corresponding to a film thickness of 50 mg / m ^{2 in} terms of Si on the inorganic treatment layer was obtained. Thereafter, evaluation was performed in the same manner as in Example 19.

<Evaluation of aluminum material>
(Example 31)
1. Preparation of surface-treated metal plate JIS5021H18 aluminum alloy plate with a thickness of 0.25 mm was used as the metal plate, and the degreasing agent 322N8 (manufactured by Nippon Paint Co., Ltd.) was used for 10 seconds in a 70 ° C. bath by a conventional method. The sample was immersed in 1% sulfuric acid at 40 ° C. for 5 seconds, washed with water and washed with pure water, and pretreated. Next, Example 1 was carried out in the treatment bath shown in F of Table 2 except that cathodic electrolysis was conducted intermittently by repeating 0.4 sec energization-0.6 sec stop four times at a current density of 7 A / dm ^2. The surface treatment aluminum plate was obtained in the same manner as described above.

2. Production of Resin-Coated Metal Plate Using the obtained surface-treated metal plate, a resin-coated metal plate for making a lid was produced by the following method. First, water-cooling immediately after thermocompression bonding through a laminating roll so that the lower layer side of the cast film in Table 4 (a) is in contact with one surface of a surface-treated metal plate heated to a plate temperature of 250 ° C. in advance. Thus, a film was coated on one side. Next, an epoxy acrylic paint was applied on the other side of the metal plate, which is the outer surface side of the lid, by roll coating, and baked at 185 ° C. for 10 minutes.

3. Evaluation of surface-treated metal plate A part of the obtained inorganic surface-treated metal plate was subjected to weight film thickness measurement, surface atomic ratio measurement, and adhesion evaluation. The results are shown in Table 7. Here, the adhesion test piece is a T peel test piece obtained by pressure-bonding the film shown in Table 4 (b) at 250 ° C., and in the evaluation of adhesion, the maximum after peeling the test piece by 10 mm or more with a tensile tester. Example 1 except that the tensile strength is 0.6 kg / 5 mm or more, ◎, 0.3 kg / 5 mm or more and less than 0.6 kg / 5 mm is ○, and less than 0.3 kg / 5 mm is x. Created in the same way.

4). Evaluation of opening of can lid Using the obtained resin-coated metal plate, a full-open can lid having a diameter of 301 was prepared by a conventional method, and then wound on a can body filled with water in a can body, and then 110 ° C for 60 minutes. A retort sterilization treatment was performed, and the resin was peeled off at the periphery of the score portion after opening immediately after cooling, and the openability of the can lid was evaluated. The results are shown in Table 7. In the table, the evaluation of the openability of the can lid is based on the observation of feathering around the opening, ◎ if no feathering is observed, ○ if there is no resin peeling less than 0.5 mm, and feathering is 0 . × 5 mm or more.

(Example 32)
1. Preparation of surface-treated metal plate Surface treatment was performed in the same manner as in Example 31 except that a JIS 3004H19 aluminum alloy plate having a thickness of 0.26 mm was used as the metal plate.

2. Preparation of resin-coated metal plate The obtained surface-treated metal plate is heated in advance to a plate temperature of 250 ° C., and the lower layer side of the cast film of (a) in Table 4 becomes the outer surface side of the can on one side of the metal plate. A resin film-coated metal plate was obtained by immediately water-cooling after thermocompression bonding through a laminating roll so that the cast film of (F) in Table 4 was in contact with and coated on the other surface.

3. Preparation of Metal Can After both sides of the obtained resin-coated metal plate were electrostatically oiled with paraffin wax, they were punched into a circle with a diameter of 154 mm, and a shallow drawn cup was prepared according to a conventional method. Subsequently, the drawn cup was simultaneously drawn and ironed twice to form a cup having a small diameter and a large height. Various characteristics of the cup thus obtained were as follows.
Cup diameter 66mm,
Cup height 128mm,
-60% of can wall thickness relative to original plate thickness
This cup is heat-treated at 220 ° C. for 60 seconds after doming to remove the distortion of the resin film. A 350 g seamless can was made.

4). Evaluation of surface-treated metal plate A part of the obtained inorganic surface-treated metal plate was subjected to measurement of weight film thickness measurement and surface atomic ratio measurement in the same manner as in Example 1, and the results are shown in Table 7.

5). Evaluation of retort adhesion of metal cans Scratches reaching the substrate over the entire circumference of the inner surface of the can 5mm below the open end of the can after flange processing and kept in hot steam at 125 ° C for 30 minutes Then, the degree of peeling of the coating resin around the inner surface of the can inner surface was observed, and the retort adhesion was evaluated. The results are shown in Table 7. In the table, the retort adhesion evaluation of the metal can was evaluated as ◯ when there was no peeled can even in a part of 20 cans, and x when there was a peeled metal can even in a part of 20 cans.

6). Corrosion resistance evaluation of metal cans After storing a metal can packed with carbonated water so that the internal pressure at 25 ° C is 3.5 kg / cm ² at 37 ° C for one week, the can temperature is lowered to 5 ° C, then the metal can From an upright state, the bottom radius portion was deformed by dropping from a height of 50 cm onto a steel plate having a thickness of 10 mm inclined 15 ° with respect to the horizontal direction. Thereafter, the bottom of the can including the bottom radius portion was cut in the circumferential direction, and the corrosion state around the bottom radius deformed portion after aging for 2 weeks at 50 ° C. in a 0.1% sodium chloride aqueous solution was observed to evaluate the corrosion resistance. The results are shown in Table 7. In the table, the corrosion resistance of metal cans was evaluated by observing the periphery of the deformed portion of the bottom radius with a stereomicroscope, and ◯ when no corrosion was observed and x when slightly corroded.

(Example 33)
After the metal plate was treated in the same manner as in Example 31 to form an inorganic surface treatment layer, a silane cup corresponding to a film thickness of 5 mg / m ^{2 in} terms of Si was formed on the inorganic treatment layer in the same manner as in Example 22. Resin coating, lid making, and evaluation were performed in the same manner as in Example 31 except that a ring agent layer was formed to form a surface-treated metal plate.

(Example 34)
After the metal plate was treated and the inorganic surface treatment layer was formed in the same manner as in Example 32, a silane cup corresponding to a film thickness of 5 mg / m ^{2 in} terms of Si was formed on the inorganic treatment layer in the same manner as in Example 22. Resin coating, canning, and evaluation were performed in the same manner as in Example 32 except that a ring agent layer was formed to form a surface-treated metal plate.

(Comparative Example 9)
In the same manner as in Example 31, a JIS 5021H18 aluminum alloy plate having a thickness of 0.25 mm was pretreated, and then an inorganic surface treatment was not performed, and a phenol-based organic surface treatment was performed in the same manner as in Example 19; In the same manner as above, resin coating, lid formation and evaluation were performed. Weight film thickness of the organic surface treatment formed at this time was 5 mg / ^{m 2} at 13 mg ^/ m 2, Zr amount in C content.

(Comparative Example 10)
In the same manner as in Example 31, a JIS 5021H18 aluminum alloy plate having a thickness of 0.25 mm was pretreated, and then a bath was prepared by a conventional method using a commercially available zirconium-based chemical conversion treatment solution (Allodin 404, manufactured by Nihon Parkerizing Co., Ltd.). Then, spray treatment was performed at a liquid temperature of 40 ° C. for 15 seconds, and immediately after that, washing with water, washing with pure water, and post-drying treatment were performed.

(Comparative Example 11)
In the same manner as in Example 32, a JIS3004H19 aluminum alloy plate having a thickness of 0.26 mm was pretreated, and then a phenolic organic surface treatment was performed in the same manner as in Example 19. Cans and evaluations were made. However, evaluation of the surface treatment metal plate evaluated the metal plate after phenol type organic surface treatment formation.

(Comparative Example 12)
In the same manner as in Example 32, after pretreatment of a JIS3004H19 aluminum alloy plate having a thickness of 0.26 mm, inorganic surface treatment was performed in the same manner as in Comparative Example 10, and in the same manner as in Example 32, resin coating, canning and Evaluation was performed.

(Comparative Example 13)
Resin coating, lid making, and evaluation were performed in the same manner as in Example 31 except that a surface-treated metal plate was obtained by performing cathodic electrolysis at a current density of 2 A / dm ² in a N treatment bath of Table 2 for 9 seconds. .

(Comparative Example 14)
Resin coating, canning, and evaluation were performed in the same manner as in Example 32 except that a surface-treated metal plate was obtained by performing cathodic electrolysis at a current density of 2 A / dm ² in a N treatment bath of Table 2 for 9 seconds. .

(Comparative Example 15)
After the metal plate was treated in the same manner as in Example 31 to form an inorganic surface treatment layer, a silane cup corresponding to a film thickness of 50 mg / m ^{2 in} terms of Si was formed on the inorganic treatment layer in the same manner as in Comparative Example 8. Resin coating, lid making, and evaluation were performed in the same manner as in Example 31 except that a ring agent layer was formed to form a surface-treated metal plate.

(Comparative Example 16)
After the metal plate was processed in the same manner as in Example 32 to form an inorganic surface treatment layer, a silane cup corresponding to a film thickness of 50 mg / m ^{2 in} terms of Si was formed on the inorganic treatment layer in the same manner as in Comparative Example 8. Resin coating, canning, and evaluation were performed in the same manner as in Example 32 except that a ring agent layer was formed to form a surface-treated metal plate.

(Comparative Example 17)
A 15% sulfuric acid aqueous solution was prepared by weight%, the counter electrode was an aluminum plate, and anodization was performed at a liquid temperature of 40 ° C. for 15 V for 15 seconds. In the same manner as in Example 31, resin coating, lid making, and evaluation were performed.

(Comparative Example 18)
Resin coating, can making, and evaluation were performed in the same manner as in Example 32 except that the anodizing treatment was performed in the same manner as in Comparative Example 17.

<Evaluation of actual cans>
(Example 35)
1. Preparation of surface-treated metal plate A cold-rolled steel plate having a thickness of 0.22 mm and a tempering degree DR8 was subjected to electrolytic degreasing, pickling, washing with water, and washing with pure water as a metal plate, followed by pretreatment. Subsequently, the treatment was performed in the same manner as in Example 1 except that the current density was 1 A / dm ^{2 in} the treatment bath of D in Table 2 and the cathodic electrolysis was repeated 12 times of 0.6 second energization-0.4 second stop. . Subsequently, dip in a 3% aqueous solution of γ-aminopropyltrimethoxysilane (product name KBM903, manufactured by Shin-Etsu Chemical Co., Ltd.), roll squeeze and dry at 120 ° C. for 1 minute. A surface-treated metal plate having a silane coupling agent layer corresponding to a film thickness of 5 mg / m ² was obtained.

2. Preparation of resin-coated metal plate The obtained surface-treated metal plate was heated in advance to a plate temperature of 250 ° C., and the lower layer side of the cast film of (a) in Table 4 was in contact with and coated on one side to become the outer surface side. A resin-coated metal plate was obtained by water-cooling immediately after thermocompression bonding via a laminating roll so that the cast film of (4) in Table 4 was coated on one side.

3. Preparation of can body and can lid After applying a processing lubricant to the obtained resin-coated metal plate, redrawing (drawing ratio 2.5) was performed to prepare a can body having an inner diameter of 65.3 mm. Subsequently, in order to remove the distortion of the resin film, heat treatment was performed at 220 ° C. for 60 seconds, and the edge of the opening end was trimmed and flanged to produce a deep drawn can with a height of 101.1 mm. On the other hand, a part of the obtained resin-coated metal plate was molded into a 211-diameter full-open lid by a conventional method.

4). Content Product Filling Test Using the can body and can lid prepared in this manner, after filling the can body with meat sauce, the full open lid was double-wrapped and subjected to retort sterilization treatment at 120 ° C. for 30 minutes.

5. Evaluation of surface-treated metal plate A portion of the obtained inorganic surface-treated metal plate before organic surface treatment was subjected to weight film thickness measurement and surface atomic ratio measurement in the same manner as in Example 1, and the results are shown in Table 8. It was.

6). Container evaluation The state of the organic coating after container molding was examined and observed for abnormalities such as peeling and perforation. Further, after filling the contents, the container was opened for 6 months after storage at 37 ° C., and it was examined whether corrosion on the inner surface side of the container or floating of the organic coating occurred. Table 8 shows the results.

(Example 36)
1. Preparation of surface-treated metal plate Cold-rolled steel sheet having a thickness of 0.17 mm and a tempering degree of DR8 as a metal plate is subjected to electrolytic degreasing, pickling, rinsing, pure water washing, pretreatment, and 0.3 g / m of nickel per side. After plating to ² , tin was plated to 0.6 g / m ² on one side and subjected to reflow treatment to form a nickel-tin-iron alloy layer. Subsequently, in the same manner as in Example 35, cathodic electrolysis and silane coupling agent treatment were performed in the treatment bath D of Table 2 to obtain a surface-treated metal plate.

2. Preparation of resin-coated metal plate The obtained surface-treated metal plate is roll-coated on both sides using an epoxy acrylic water-based paint so that the coating thickness after baking is 10 μm and subjected to baking treatment at 200 ° C. for 10 minutes. Thus, a resin-coated metal plate was obtained.

3. Preparation of can body and can lid After applying a processing lubricant to the obtained resin-coated metal plate, it was subjected to drawing (drawing ratio 1.3) to prepare a can body having an inner diameter of 83.3 mm. Subsequently, trimming processing and flange processing of the end portion of the opening were performed, and a drawn can having a height of 45.5 mm was created. On the other hand, a part of the obtained resin-coated metal plate was molded into a 307-diameter full-open lid by a conventional method.

4). Contents filling test Using the can body and can lid prepared in this manner, the can body was filled with tuna oil, and then the full open lid was wound twice and subjected to retort sterilization at 115 ° C for 60 minutes. .
5. Evaluation of surface-treated metal plate In the same manner as in Example 35, the weight film thickness measurement and the surface atomic ratio measurement of the inorganic surface treatment layer were performed.
6). Container evaluation Container evaluation was carried out in the same manner as in Example 35 except that the presence or absence of sulfur discoloration was examined after opening the can.

(Example 37)
1. Preparation of surface-treated metal plate A cold-rolled steel plate having a thickness of 0.22 mm and a tempering degree T4 as a metal plate is subjected to electrolytic degreasing, pickling, water washing, pure water washing, pretreatment, and 2.0 g / m tin per side. ² after plating, followed by reflow treatment, followed by cathodic electrolysis with a current density of 0.6 A / dm ^{2 in} the treatment bath of Table 2 with 0.6 second energization-0.4 second stop 16 times repeated. Except for the above, cathodic electrolysis was performed in the same manner as in Example 1 to obtain a surface-treated metal plate for can bodies.
On the other hand, a cold-rolled steel sheet having a tempering degree T4 of 0.21 mm was treated in the same manner as described above to obtain a surface-treated metal sheet for can lids.

2. Preparation of resin-coated metal plate, can barrel and can lid Using a surface-treated metal plate for can barrels, the film thickness after baking is 5 μm on the inner surface side, except where the epoxy acrylic water-based paint hits the seam portion of the can barrel. Margin coating was performed so that the outer surface side would be 3 μm, and baking and curing was performed for 10 minutes in a hot air drying furnace to obtain a resin-coated metal plate. The prepared resin-coated metal plate is cut into a blank shape, and the blank is welded into a cylindrical shape by a commercially available electric resistance welder using a wire electrode. Next, a solvent is formed on the inner and outer surfaces of the weld seam of the can body. Type epoxy urea-based repair paint is spray-coated to a dry film thickness of 40 μm, then baked in a hot air drying oven for 3 minutes, and the seam is covered to weld the can body (can diameter 65.4 mm, can body height 122 mm).
On the other hand, an epoxy acrylic water-based paint is roll-coated on both sides so that the coating thickness after baking is 10 μm on the surface-treated metal plate for can lids, and subjected to baking treatment at 200 ° C. for 10 minutes. , 209 diameter shell lid.
One opening end of the can body was subjected to flange processing and neck-in processing. After the 209-diameter lid was wound, the other opening end was subjected to triple neck-in processing and flange processing.

3. Content product filling test After filling a coffee beverage at 50 ° C, a 206-diameter aluminum SOT lid was double-wrapped and subjected to a retort sterilization treatment at 125 ° C for 25 minutes.
4). Evaluation of surface-treated metal plate In the same manner as in Example 35, weight film thickness measurement and surface atomic ratio measurement were performed.
5. Container evaluation Container evaluation was performed in the same manner as in Example 35 except that the amount of iron elution after opening the can was also measured.

(Example 38)
1. Preparation of surface-treated metal plate A tin-coated surface-treated steel sheet was obtained in the same manner as in Example 37 except that tin was plated to 11.2 g / m ² and then reflow treatment was performed. On the other hand, the same treatment plate as in Example 37 was used as the surface treatment metal plate for the can lid.

2. Preparation of resin-coated metal plate, can body and can lid The surface-treated metal plate for can body is cut into a blank shape without painting, and the blank is formed into a cylindrical shape with a commercially available resistance welding machine using wire electrodes. After welding, spray coating of solvent-type epoxy urea-based repair paint on the inner and outer surfaces of the welded seam of the can body so that the dry coating thickness is 40 μm, then baked in a hot air drying oven for 3 minutes to cover the joint A can body (can diameter: 74.1 mm, can body height: 81.2 mm) was prepared.
On the other hand, an epoxy acrylic water-based paint is roll-coated on both sides so that the coating thickness after baking is 10 μm on the surface-treated metal plate for can lids, and subjected to baking treatment at 200 ° C. for 10 minutes. , Molded into a 301-diameter shell lid.
One opening end of the can body was subjected to flange processing and neck-in processing, and after the 301-diameter lid was wound, the other opening end was subjected to triple neck-in processing and flange processing.

3. Content Product Filling Test After hot pack filling the resulting can with tangerine syrup, the 301-diameter lid was double wrapped around the opening and sterilized with hot water.
4). Evaluation of surface-treated metal plate In the same manner as in Example 35, weight film thickness measurement and surface atomic ratio measurement were performed.
5. Container evaluation The same as in Example 35, except that the container was opened after storage at 37 ° C. for 6 months, and whether or not uneven discoloration of the inner surface of the container had occurred and whether the contents had not browned or not was evaluated. evaluated.

(Example 39)
1. Preparation of surface-treated metal plate Cold-rolled steel sheet having a thickness of 0.22 mm and a tempering degree T4 as a metal plate is subjected to electrolytic degreasing, pickling, water washing, pure water washing, pretreatment, and nickel per one side of 0.03 g / m. After plating to ² , tin was plated to 1.3 g / m ² on one side, followed by reflow treatment, and then, in the same manner as in Example 37, cathodic electrolysis was performed in the treatment bath of Table A. A surface-treated metal plate for can bodies was obtained. On the other hand, a cold-rolled steel sheet having a tempering degree T4 of 0.21 mm was treated in the same manner as described above to obtain a surface-treated metal sheet for can lids.

2. Preparation of resin-coated metal plate, can body and can lid Using the surface-treated metal plate for can body, the film thickness after baking is 5 μm on the inner surface side except for the place where the epoxy phenol solvent type paint is applied to the joint part of the can body. Margin coating was performed so that the outer surface side would be 3 μm, and baking and curing was performed for 10 minutes in a hot air drying furnace to obtain a resin-coated metal plate. The prepared resin-coated metal plate is cut into a blank shape, and the blank is welded into a cylindrical shape by a commercially available electric resistance welder using a wire electrode. Next, a solvent is formed on the inner and outer surfaces of the weld seam of the can body. Type epoxy urea-based repair paint is spray-coated to a dry film thickness of 40 μm, then baked in a hot air drying oven for 3 minutes, and the seam is covered to weld the can body (can diameter 65.4 mm, can body height 122 mm).
On the other hand, an epoxy phenol solvent type paint is roll-coated on both sides so that the coating thickness after baking is 10 μm on the surface-treated metal plate for can lid, and after baking treatment at 200 ° C. for 10 minutes, , 209 diameter shell lid.
One opening end of the can body was subjected to flange processing and neck-in processing. After the 209-diameter lid was wound, the other opening end was subjected to triple neck-in processing and flange processing.

3. Content Product Filling Test After hot-packing orange juice at 93 ° C., a commercially available 206-diameter aluminum SOT lid was double wrapped and sealed.
4). Evaluation of surface-treated metal plate In the same manner as in Example 35, weight film thickness measurement and surface atomic ratio measurement were performed.
5. Container Evaluation Container evaluation was performed in the same manner as in Example 37.

(Example 40)
1. Preparation of surface-treated metal plate A cold-rolled steel plate having a thickness of 0.195 mm and a tempering degree T3 as a metal plate was subjected to electrolytic degreasing, pickling, water washing, pure water washing, pretreatment, and 1.0 g / m tin per side. after plating to ^2, followed by the same manner as in example 37, and subjected to cathodic electrolysis treatment in the processing bath in Table 2 a, to obtain a can barrel for surface treated metal sheet.
On the other hand, using a JIS5182H19 aluminum alloy plate having a thickness of 0.285 mm as a metal plate, the current density was set to 5 A / dm ^{2 in} the treatment bath of Table 2A, and 0.6-second energization-0.4-second stop was repeated 8 times. A surface treatment metal plate for can lids was obtained in the same manner as in Example 31 except that cathode electrolysis was performed.

2. Preparation of resin-coated metal plate The obtained surface metal plate for can body and can lid is heated in advance to a plate temperature of 220 ° C., and the lower layer side of the cast film of (e) in Table 4 is in contact with one side to cover The resin-coated metal plate was obtained by immediately water-cooling after thermocompression bonding through a laminating roll so that the cast film of (4) in Table 4 was coated on the other surface on the outer surface side. .

3. Preparation of can body and can lid Paraffin wax was electrostatically coated on both sides of the resin-coated metal plate for the can body, and then punched into a circle having a diameter of 140 mm, and a shallow drawn cup was prepared according to a conventional method. The drawn cup was then redrawn and ironed twice to obtain a deep drawn ironing cup having a small diameter and a large height. Various characteristics of the cup thus obtained were as follows.
Cup diameter 52mm,
Cup height 138mm,
-50% of can wall thickness with respect to original plate thickness
This cup is heat-treated at 220 ° C. for 60 seconds after doming molding, followed by trimming of the end of the opening, curved surface printing, neck-in to 200 diameters, flange processing, and re-flange processing. A 250 g seamless can was made.
In addition, a 200-diameter SOT lid was prepared from a resin-coated metal plate for can lids according to a conventional method.

4). Content product filling test Cola was cold packed in the 250 g can at 5 ° C., and the SOT lid was immediately wound twice and sealed.
5. Evaluation of surface-treated metal plate In the same manner as in Example 35, weight film thickness measurement and surface atomic ratio measurement were performed.
6). Container Evaluation Container evaluation was performed in the same manner as in Example 37.

(Example 41)
1. Preparation of surface-treated metal sheet and resin-coated metal sheet Example 32, except that cathodic electrolysis was performed intermittently by repeating 0.4 second energization-0.6 second stop twice at a current density of 10 A / dm ² in the treatment bath shown in A of 2. The same treatment was performed to obtain a surface-treated aluminum plate. The resin coating was performed in the same manner as in Example 35 except that the cast film of (F) in Table 4 was coated on both surfaces.

A paraffin wax was electrostatically applied to both surfaces of the obtained resin-coated metal plate for a can body, and then punched into a circular shape with a diameter of 166 mm, and a shallow drawn cup was prepared according to a conventional method. Subsequently, this shallow drawn cup was redrawn and ironed, and a can was obtained by deep drawing and ironing. Various characteristics of the can thus obtained were as follows.
Can body diameter 66mm,
Can body height 128mm,
The thickness of the can wall relative to the original plate thickness -63%
This can body was subjected to heat treatment at 220 ° C. for 60 seconds after doming molding in accordance with a conventional method to remove distortion of the resin film, followed by trimming of the end of the opening, curved surface printing, neck-in to 206 diameters, flange The 350g seamless can was made by processing and re-flange processing. On the other hand, a 206-diameter SOT lid was prepared from a resin-coated metal plate for can lids according to a conventional method.

2. Content Product Filling Test After cold-packing beer into the 350 g can at 5 ° C., the SOT lid was double wrapped and sealed.
3. Evaluation of surface-treated metal plate In the same manner as in Example 35, weight film thickness measurement and surface atomic ratio measurement were performed.
4). Container evaluation Container evaluation was carried out in the same manner as in Example 32, except that the aluminum elution amount after opening the can was also measured.

It is the figure which measured the peak of O1s, Al2p, F1s by XPS about the inorganic surface treatment layer of the surface treatment metal plate of this invention. It is the figure which measured the peak of Al2p by XPS about the inorganic surface treatment layer of the surface treatment metal plate of this invention. It is the figure which compared the S1s peak by XPS about the inorganic surface treatment layer of the surface treatment gold slab of this invention, and the S1s peak by XPS of the anodic oxidation alumite by a sulfuric acid. It is the figure which measured the N1s peak by XPS about the outermost surface of the surface treatment metal plate in which the organic surface treatment layer of this invention was formed. It is a figure which shows the cross-section of an example of the surface treatment metal plate of this invention. It is a figure which shows the cross-section of another example of the surface treatment metal plate of this invention. It is a figure which shows the cross-section of another example of the surface treatment metal plate of this invention. It is a figure which shows the relationship between total electrolysis time and Al weight film thickness. It is a figure which shows the cross-section of an example of the resin coating metal plate of this invention. It is a figure which shows the cross-section of another example of the resin coating metal plate of this invention. It is a side view which shows an example of the metal can of this invention. It is a top view of an example of an easy open can lid of the present invention. It is sectional drawing of the easy open can lid shown in FIG.

Claims (18)

A metal can comprising a surface-treated metal plate having an inorganic surface treatment layer formed by precipitation by cathodic electrolysis from an aqueous solution on the surface of a metal substrate (excluding Al), wherein the inorganic surface treatment layer comprises Al And a resin-coated metal plate made of at least one of aluminum hydroxide or oxyhydroxide mainly composed of O and O , and Zr, Ti, and coated with an organic resin on at least one surface of the surface-treated metal plate. A metal can characterized by comprising. The inorganic O and M contained in the outermost surface of the surface treatment layer (where, M is a A l, Ti, at least on one or more kinds of Zr) atomic ratio of, 1 <O / M <5.5 there claim 1 Symbol placing a metal can. Wherein contained in the outermost layer of the inorganic surface-treating layer (P + S) and M (where, M is a A l, Ti, among the at least one or more kinds of Zr) atomic ratio is, (P + S) / M <0. The metal can according to claim 1 or 2, which is 25. The thickness of the inorganic surface-treating layer, the weight film thickness of Al, metal can according to any one of claims 1 to 3 is 5 to 100 mg / ^{m 2.} Said metal substrate is tin, nickel, zinc, metal can according to any one of claims 1 to 4, characterized in that a surface-treated steel sheet having a plating layer comprising one or more iron. The metal can according to any one of claims 1 to 5, wherein a surface exposure rate of a main element of the metal base is less than 5%. The metal according to any one of claims 1 to 6, wherein an organic surface treatment layer mainly comprising a silane coupling agent having a Si amount of 0.8 to 30 mg / m ² is formed on the inorganic surface treatment layer. Cans .   The metal can according to any one of claims 1 to 7, wherein an organic surface treatment layer mainly composed of a phenol-based water-soluble organic compound is formed on the inorganic surface treatment layer. The outermost layer of the said organic surface treatment layer contains N, The metal can of Claim 7 or 8 characterized by the above-mentioned. A can lid made of a surface-treated metal plate having an inorganic surface treatment layer formed by deposition by cathodic electrolysis from an aqueous solution on the surface of a metal substrate (excluding Al), wherein the inorganic surface treatment layer is made of Al And a resin-coated metal plate in which an organic resin is coated on at least one surface of a surface-treated metal plate made of aluminum hydroxide or oxyhydroxide mainly composed of O and O, and at least one of Zr and Ti. A can lid characterized by comprising. The atomic ratio of O and M (wherein M is at least one of Al, Ti, and Zr) contained in the outermost surface of the inorganic surface treatment layer is 1 <O / M <5.5. Item 10. The can lid according to item 10 . The atomic ratio of (P + S) and M (wherein M is Al and at least one of Ti and Zr) contained in the outermost surface layer of the inorganic surface treatment layer is (P + S) / M <0.25. The can lid according to claim 10 or 11 . The can lid according to any one of claims 10 to 12, wherein a film thickness of the inorganic surface treatment layer is 5 to 100 mg / m ² in terms of a weight film thickness of Al . The can lid according to any one of claims 10 to 13, wherein the metal substrate is a surface-treated steel sheet having a plating layer containing one or more of tin, nickel, zinc, and iron. The can lid according to any one of claims 10 to 14, wherein a surface exposure rate of a main element of the metal base is less than 5% . The can according to any one of claims 10 to 15, wherein an organic surface treatment layer mainly comprising a silane coupling agent having a Si amount of 0.8 to 30 mg / m ² is formed on the inorganic surface treatment layer. Lid . The can lid according to any one of claims 10 to 16, wherein an organic surface treatment layer mainly composed of a phenol-based water-soluble organic compound is formed on the inorganic surface treatment layer . The can lid according to claim 16 or 17, wherein the outermost layer of the organic surface treatment layer contains N.

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