JPH1148403A - Surface-treated metallic sheet excellent in perspiration resistance and lubricity and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface-treated metallic sheet having excellent resistance to corrosion, scratching, and perspiration by providing, on at least one side of a metallic sheet, an organic resin double layer comprising a bottom layer composed of organic resin, and a top layer composed of organic resin containing silica and a lubricant. SOLUTION: At least one side of a metallic sheet is provided with an organic resin double layer comprising a bottom layer composed of organic resin, and a top layer composed of organic resin containing silica and a lubricant, or a top layer composed of organic resin containing silica and a rust-proof agent. In this case, a copper sheet, an aluminum sheet, a stainless steel sheet, or the like is preferable for a base metallic sheet, and aqueous urethane resin, acrylic resin, or the like is preferable for the organic resin layer of the lower layer for conserving environment. Aqueous resin such as olefin modified acrylic resin, which can easily disperse silica and lubricant powder, is preferable for the top layer resin for environment conservation, and polytetrafluoroethylene or the like, which can be dispersed in the aqueous resin solution, is preferable for the lubricant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-treated metal sheet excellent in corrosion resistance, scratch resistance, sweat resistance, and lubricity, and a method for producing the same. More specifically, a multi-layer organic resin layer comprising a lower layer made of an organic resin and an upper layer made of an organic resin containing silica and a lubricant on a surface-treated metal plate used for a chassis or a copying machine of a home appliance. To improve the corrosion resistance, reduce the abrasion and abrasion of the surface treatment film due to the rubbing of the copy sheet when the copy sheet is taken in and out of the copying machine, etc., improve the slipperiness, and make contact with fingers. Surface-treated metal plate that significantly reduces discoloration and rust due to sweat
And its manufacturing method.

[0002]

2. Description of the Related Art As a surface-treated metal plate used in a copying machine or the like, a galvanized layer and a colored galvanized layer are formed on a metal plate, and a surface composed of chromium oxide, hydrated oxide, and silica is formed thereon. Surface treated metal plate provided with a treatment layer, or surface treatment metal plate provided with a surface treatment layer to which silica is added as a further upper layer (Japanese Patent Laid-Open No. 8-27749).
No. 8), which describes that this surface-treated steel sheet has excellent scratch resistance and abrasion resistance when the copy paper rubs the surface-treated layer. However, in applications such as home appliance chassis and copiers, fingers frequently touch the surface when handling home appliances or copying work of copiers, etc. Rust may occur on the metal plate due to salt after sweat or sweat is dried, and discoloration and rust may occur even if the above-mentioned surface-treated metal plate with excellent scratch resistance and abrasion resistance is used. It was difficult to prevent. As a reason for this, it is considered that sweat permeates the interface between the silica and the resin contained in the surface treatment layer, reaches the metal substrate, and corrodes the metal substrate.
Further, the slipperiness of the paper on the surface-treated steel sheet is not always sufficient, and it has been difficult to completely avoid troubles such as paper jam during copying.

[0003]

SUMMARY OF THE INVENTION The present invention improves corrosion resistance, reduces scratches and abrasion of a surface treatment film due to abrasion of a copy sheet when a copy sheet is taken in and out, and improves slipperiness. It is another object of the present invention to provide a surface-treated metal sheet having excellent corrosion resistance, scratch resistance, and sweat resistance, in which discoloration and rust caused by sweat when a finger comes into contact are significantly reduced, and a method for producing the same. .

[0004]

According to the present invention, a metal plate is provided on at least one surface with a multi-layer organic resin layer comprising a lower layer made of an organic resin and an upper layer made of an organic resin containing silica and a lubricant. The above-mentioned sweat resistance and lubrication, wherein the surface-treated metal sheet having excellent sweat resistance and slipperiness, or the upper layer is made of an organic resin containing a rust inhibitor in addition to silica and a lubricant. A surface-treated metal plate having excellent properties, wherein the organic resin forming the lower layer is a urethane resin, an acrylic resin, an olefin-modified acrylic resin, or a polyester resin, and the organic resin forming the upper layer is an olefin. A modified acrylic resin, and the lubricant is polytetrafluoroethylene or polyethylene wax. Zinc or the metal plate, the surface,
The steel sheet is characterized by being plated with at least one of cobalt, tin, and nickel, and further having a chromium hydrated oxide film formed thereon. The present invention also provides an organic resin in which colloidal silica and a lubricant powder are dispersed after immersing a metal plate in a solution containing an organic resin, followed by drying to form a lower organic resin layer on the metal plate surface. Or a solution containing colloidal silica and a lubricant powder dispersed therein, further immersed in a solution containing an organic resin to which a rust inhibitor has been added, and then dried to form an organic resin layer serving as an upper layer containing silica and a lubricant. A method for producing a surface-treated metal sheet having excellent sweat resistance and slipperiness, characterized by being formed, is also an object of the invention.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, at least one surface of a metal plate is provided with a lower layer made of an organic resin, an upper layer made of an organic resin containing silica and a lubricant, or a rust inhibitor in addition to silica and a lubricant. By providing a multilayer organic resin layer consisting of an upper layer made of an organic resin containing
Corrosion resistance is improved, scratches and abrasion of the surface treatment film due to rubbing of copy paper when copying paper is taken in and out of a copying machine and the like are reduced, and slippage is improved, and discoloration due to sweat when fingers and fingers are contacted is improved. A surface-treated metal plate excellent in corrosion resistance, scratch resistance, sweat resistance and slipperiness, in which the generation of rust was remarkably reduced, was obtained. Hereinafter, the present invention will be described in detail.

First, as a base metal plate used for the surface-treated metal plate of the present invention, besides a copper plate, a copper alloy plate, an aluminum plate, an aluminum alloy plate, a stainless steel plate and the like,
Any one of zinc, cobalt, tin, and nickel is plated on a single-layer, or two or more of zinc-cobalt, zinc-nickel, zinc-nickel-cobalt, on a hot-rolled steel sheet or a cold-rolled steel sheet from which scale has been removed. , Zinc-nickel-
A steel sheet which has been subjected to a multi-layer plating of cobalt-molybdenum, nickel-tin, or the like, or an alloy plating, or a steel sheet having a chromium hydrated oxide film formed thereon is further applicable. Further, a colored plated steel sheet in which a plating layer is colored by anodizing, cathodic treatment, or immersion in a bath containing an oxidizing agent as a main component is also applicable.

Next, it is preferable to provide a thin organic resin layer as a lower layer of the multiple organic resin layers on the above-mentioned base metal plate, which is an object of the present invention to provide excellent corrosion resistance and sweat resistance, in particular, sweat resistance. It is extremely important in obtaining a surface-treated metal plate having trace rust. Even if sweat containing moisture and salts permeates the upper resin layer containing silica and lubricant described below,
The underlying thin organic resin layer prevents direct contact with the base metal plate. Therefore, excellent corrosion resistance and sweat resistance can be ensured. The resin constituting the lower organic resin layer is not particularly limited, but from the viewpoint of environmental protection, an aqueous resin that can be dissolved or dispersed in water is more preferable than an organic solvent-based resin, and a urethane resin, an acrylic resin, and an olefin are preferable. Modified acrylic resins or polyester resins are particularly preferred.

As a method for forming the lower organic resin layer on the base metal plate, there are known laminating methods such as film laminating and extrusion laminating, powder coating, roll coating, spraying, electrostatic coating and the like. Although the coating method is applicable, the thickness of the organic resin layer may be relatively thin, from the viewpoint of simplicity of coating work, and economy, immersing the base metal plate in a solution in which the resin is dissolved, It is preferable to employ a method of removing excess resin solution using a squeezing roll or the like and then drying. As a drying method, any means such as hot air drying, a gas oven, an electric oven, and an induction heating furnace may be used, and the most advantageous method may be adopted from the viewpoint of the throughput and economy. Also, after the paint film is generated,
UV irradiation or electron beam irradiation may be used in combination.

The thickness of the lower organic resin layer is preferably 0.1 to 6 g / m ² in terms of dry weight. 0.1 g / m ²
If it is less than 30, sufficient corrosion resistance and sweat resistance cannot be obtained. 6g
If it exceeds / m ² , the effect will be saturated and it will not be economical.

Next, the provision of an organic resin layer containing silica and a lubricant as an upper layer of the above-mentioned multiple organic resin layers has excellent scratch resistance which is another object of the present invention. It is extremely important for obtaining a surface-treated metal plate having improved slipperiness with paper or the like. By including hard silica in the organic resin layer, the hardness of the entire layer is increased, and the scratch resistance and the wear resistance are improved. In addition, by including a lubricant powder having a high slip property in the organic resin layer, the friction coefficient of the layer surface is reduced, the slip property with paper or the like is improved, and the wear resistance is further improved. Further, by adding a rust inhibitor in addition to the silica and the lubricant, the corrosion resistance is remarkably improved.

The resin constituting the upper organic resin layer is not particularly limited, but it is easier to disperse the silica and the lubricant powder and dissolve or disperse in water than the organic solvent resin from the viewpoint of environmental protection. Possible aqueous resins are preferred, and olefin-modified acrylic resins, urethane-modified acrylic resins, and fluorine-modified acrylics are particularly preferred.

As described above, the upper organic resin is preferably aqueous. In order to use the aqueous resin to contain silica in the organic resin layer, aqueous colloidal silica must be added to the aqueous solution in which the aqueous resin is dissolved. Can be applied on a base metal plate and dried. The hard powder to be contained in the organic resin layer is not particularly limited, but can be dispersed in an aqueous solution as described above, is inexpensive, and a transparent film is obtained, and the lower organic resin layer, or Silica which can make the color of the base metal plate distinguishable through the lower organic resin layer is particularly preferable.

As the lubricant to be contained in the upper organic resin, those which can be dispersed in an aqueous solution in which the above-mentioned aqueous resin is dissolved, for example, polytetrafluoroethylene,
Polyethylene wax or the like can be applied. When forming a colored surface treatment film, a powder of a colored inorganic lubricant such as molybdenum disulfide, graphite, boron nitride or the like can be used. However, since these inorganic lubricant powders are difficult to disperse in an aqueous solution, it is necessary to use an organic solvent-based resin.

In order to improve the corrosion resistance, in addition to the above silica and lubricant, a rust inhibitor is further contained in the upper layer organic resin, when ammonium chromate, sodium chromate, ammonium bichromate, bichromate is used. Addition of any one or more of sodium citrate, potassium dichromate, barium metaborate and the like is preferable, and addition of ammonium chromate or sodium chromate is particularly preferable.

As a method of forming the upper organic resin layer on the base metal plate, a known coating method such as a roll coating method, a spray method, and an electrostatic coating method can be applied. As in the case of forming, from the viewpoint that the thickness of the organic resin layer may be relatively thin, simplicity of the coating operation, and economy, the base metal plate is immersed in a solution in which the resin is dissolved, and a squeezing roll is formed. It is preferable to employ a method of removing the excess resin solution by using the method described above and then drying. The drying method is the same as when the lower organic resin layer is formed,
Any means such as hot-air drying, a gas oven, an electric oven, and an induction heating furnace may be used, and the most advantageous method may be adopted from the viewpoint of the processing amount and economy. After the coating film is formed, UV irradiation or electron beam irradiation may be used in combination.

The upper organic resin layer preferably has a composition of 5 to 70% by weight of silica, 3 to 20% by weight of a lubricant and the balance of an organic resin. If the amount of silica and the lubricant is less than 8% by weight, sufficient scratch resistance, abrasion resistance, and good slipperiness cannot be obtained. If the surface-treated metal plate is subjected to a process such as bending, the surface-treated film will crack.

When the upper organic resin layer further contains a rust inhibitor in addition to silica and a lubricant, the rust inhibitor is added to the solution for obtaining the above-mentioned silica and lubricant film composition of the organic resin film. The treatment is performed using a solution containing 1 to 30 g / l. If the amount of the rust inhibitor is less than 1 g / l, no effect of improving the corrosion resistance is recognized, and if it exceeds 30 g / l, no further effect of improving the corrosion resistance is recognized, and it is not economical.

The thickness of the upper organic resin layer is 0.1% by dry weight.
It is preferably ⁵ to 6 g / m ² . If it is less than 0.5 g / m ² , sufficient scratch resistance, abrasion resistance, and good slip properties cannot be obtained. If it exceeds 6 g / m ² , the effect will be saturated and it will not be economical. As described above, a surface having excellent sweat resistance and lubricity obtained by providing a multi-layered organic resin layer comprising a lower layer made of an organic resin and an upper layer made of an organic resin containing silica and a lubricant on a metal plate. A treated metal plate is obtained.

[0019]

The present invention will be described in more detail with reference to the following examples. Annealed and temper-rolled cold-rolled steel sheets (thickness:
(0.50 mm) as a plating base plate, cathodic electrolytic degreasing in an alkaline solution, pickling in sulfuric acid, applying a single plating or alloy plating shown in Table 1, followed by chromate treatment, and a chromium solution on the plating. A hydrated oxide film was formed.

Next, these plated steel sheets were immersed in an aqueous resin solution having the composition shown in Table 1, and the excess resin solution was removed using a squeezing roll, followed by hot-air drying. An organic resin layer was formed.

Next, the plated steel sheet on which the lower organic resin layer was formed as described above was immersed in an aqueous olefin-modified acrylic resin solution containing silica and a lubricant having the composition shown in Table 1, and drawn. Excess resin solution was removed using a roll, followed by hot-air drying to form a lower organic resin layer having a thickness shown in Table 1.

[0022]

[Table 1]

The surface-treated steel sheet having a multilayer organic resin layer comprising a lower layer made of an organic resin and an upper layer made of an organic resin containing silica and a lubricant, thus obtained, is shown below. Characteristics were evaluated for the items. 1) Sweat Resistance An artificial sweat was prepared based on JIS-K2246, dropped on a surface-treated steel plate of a sample, left standing for 3 minutes, wiped off, and visually evaluated for the degree of discoloration of the dropped portion. 2) Sweat scar rust resistance Artificial sweat based on JIS-K 2246 is applied on a surface-treated steel sheet of a sample, dried, and then left in a constant temperature and humidity atmosphere of 60 ° C. and 95% for 96 hours. The degree was visually evaluated. 3) Scratch resistance Pea paper (64 to 70 g /
m ² ), and rubbed 2000 times with a load of 400 gf applied from above, and the degree of flaws generated on the surface was visually evaluated. 4) Workability The surface treatment of the sample was bent 180 degrees at a radius of 1 mm, and the degree of cracks generated in the bent portion was visually evaluated. 5) Corrosion resistance A salt water spray test for 72 hours was carried out based on JIS-Z2371, and the degree of rust generation was visually evaluated. Each characteristic was evaluated on a scale of 1 (poor) to 5 (excellent). Table 2 shows the evaluation results.

[0024]

[Table 2]

As shown in Table 2, the surface-treated metal sheet of the present invention is excellent in all of sweat resistance, sweat rust resistance, scratch resistance, workability and corrosion resistance.

[0026]

According to the present invention, there are provided a lower layer made of an organic resin and an upper layer made of an organic resin containing silica and a lubricant on a surface-treated metal plate, or an organic resin containing a rust inhibitor in addition to silica and a lubricant. A surface-treated metal plate having excellent corrosion resistance, scratch resistance, sweat resistance, and lubricity provided with a multilayer organic resin layer comprising an upper layer comprising When a metal plate is applied to a copying machine or the like, the scratches and abrasion of the surface treatment film due to the rubbing of the copy paper when the copy paper is taken in and out are reduced, the slipperiness is improved, and sweat is generated when a finger comes into contact with the metal plate. Discoloration and rust are significantly reduced.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiyuki Sugimoto 1296, Higashi-Toyoi, Kudamatsu-shi, Yamaguchi Pref.

Claims (12)

[Claims] 1. A metal plate provided on at least one surface with a multi-layer organic resin layer comprising a lower layer made of an organic resin and an upper layer made of an organic resin containing silica and a lubricant. Excellent surface treated metal plate. 2. The surface-treated metal according to claim 1, wherein the upper layer is made of an organic resin containing a rust inhibitor in addition to silica and a lubricant. Board. 3. The surface-treated metal plate having excellent sweat resistance and lubricity according to claim 1, wherein the organic resin constituting the lower layer is a urethane resin. 4. The surface-treated metal sheet having excellent sweat resistance and lubricity according to claim 1, wherein the organic resin constituting the lower layer is an acrylic resin. 5. The surface-treated metal plate having excellent sweat resistance and lubricity according to claim 1, wherein the organic resin constituting the lower layer is an olefin-modified acrylic resin. 6. The method according to claim 1, wherein the organic resin constituting the lower layer is a polyester resin.
A surface-treated metal plate having excellent sweat resistance and lubricity described in 1. 7. The surface-treated metal sheet having excellent sweat resistance and lubricity according to claim 1, wherein the organic resin constituting the upper layer is an olefin-modified acrylic resin. 8. The surface-treated metal plate having excellent sweat resistance and lubricity according to claim 1, wherein the lubricant is polytetrafluoroethylene. 9. The surface-treated metal plate having excellent sweat resistance and lubricity according to claim 1, wherein the lubricant is polyethylene wax. 10. The steel plate according to claim 1, wherein the metal plate is a steel plate having a surface plated with at least one of zinc, cobalt, tin, and nickel, and further having a chromium hydrated oxide film formed thereon. The surface-treated metal sheet according to any one of claims 1 to 9, which is excellent in sweat resistance and lubricity. 11. An organic resin in which a metal plate is immersed in a solution containing an organic resin, and then dried to form a lower organic resin layer on the surface of the metal plate, and then colloidal silica and a lubricant powder are dispersed therein. And dipping in a solution containing, and then drying to form an organic resin layer serving as an upper layer containing silica and a lubricant.
10. The method for producing a surface-treated metal sheet having excellent sweat resistance and lubricity described in any one of 10 above. 12. A metal plate is immersed in a solution containing an organic resin, and then dried to form a lower organic resin layer on the surface of the metal plate. Then, colloidal silica and a lubricant powder are dispersed to further prevent the metal plate. 11. An organic resin layer which is immersed in a solution containing an organic resin to which a rust agent has been added, and then dried to form an organic resin layer serving as an upper layer containing silica and a lubricant. For producing a surface-treated metal sheet having excellent sweat resistance and lubricity.