WO2014081089A1

WO2014081089A1 - Method for surface treating metal articles

Info

Publication number: WO2014081089A1
Application number: PCT/KR2013/002837
Authority: WO
Inventors: 윤주식; 유재인
Original assignee: 주식회사 위스코하이텍
Priority date: 2012-11-26
Filing date: 2013-04-05
Publication date: 2014-05-30

Abstract

According to the present invention, a method for surface treating metal articles includes: removing oils from the surface of a metal article; removing and neutralizing a material for removing oils from the surface of the metal article; and surface treating the washed metal article, wherein the method for surface treating a metal article includes the steps of: spraying a solution wherein a surface treating solution or alcohol is sprayed onto the surface of the washed metal article and wherein the surface treating solution is prepared by mixing water with either ethanol (C₂H₅OH) or acetone (CH₃COCH₃); and producing an oxidized film layer wherein an oxidized film layer is formed on the surface of the metal article by combusting or half-combusting the metal article treated in the solution spraying step. Further, the surface treating solution is prepared by mixing ethanol (C₂H₅OH), acetone (CH₃COCH₃), and water, wherein the ethanol is mixed in a volume of 1 to 50 times the water volume, and the acetone is mixed in a volume of 0.05 to 1 times the ethanol volume.

Description

Surface Treatment of Metal Products

The present invention relates to a method for treating a surface of a metal product, and more particularly, to a method for treating a surface of a metal product to enable the rapid formation of an oxide layer or the like on the surface of the metal product.

Generally, about three quarters of the chemical elements known to date are metals, and these metals include aluminum (Al), iron (Fe), copper (Cu), etc., and are usually crystalline solids, and in most cases have relatively simple crystal structure. Since the arrangement of atoms is dense and highly symmetrical, and the number of outermost electrons of a metal atom is less than half of its maximum number, the metals do not easily form compounds, but usually have more than half of the maximum number of valence electrons. Branches bind more easily with nonmetals oxygen and sulfur.

It is widely used in automobile and aircraft parts, mobile phone cases, laptop computer cases, eyeglass frames, kitchen appliances, etc. according to the use of metal materials.Magnesium alloy, aluminum and aluminum alloy, titanium and titanium alloy, iron and alloy iron, copper and copper alloy It is widely used as a product in various fields according to the characteristics of materials such as.

In order to form an oxide layer on the surface of the metal, an oxide layer is formed on the surface of the metal by a surface treatment method such as anodizing, anodizing, and plasma electrolytic oxidation.

For example, in order to surface-treat a product made of a magnesium alloy, a surface of a magnesium alloy product is surface-treated by a surface treatment method such as anodizing or plasma electrolytic oxidation to form a thin film layer such as MgO. .

In other words, the electrolyte used in the surface treatment method mainly uses sodium hydroxide (NaOH), and the hydroxyl group (OH-) separated from the sodium hydroxide bonds to the surface layer of the magnesium alloy product, which is formed inside the oxide film thus formed. The oxide is formed with a strong current field to form MgO and Mg (OH) ₂ thin film layers on the surface layer of the magnesium alloy product.

However, the prior art as described above has a drawback in that it takes a long time to form an oxide layer on the surface layer of the product, so that the surface of the product cannot be processed more quickly.

Furthermore, conventionally, there is a technique of forming a coating layer by coating a surface of a metal product or forming a metal coating layer by sputtering. However, when a coating layer or a metal coating layer is formed without treating the surface of the metal product, the metal layer is formed between the metal surface and the coating layer. Alternatively, there is a disadvantage in that the adhesion between the metal surface and the metal coating layer is low, so that the coating layer and the metal coating layer peel off easily.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to spray the surface treatment solution on the surface of the metal product and then to form the oxide layer quickly by direct weaving or heat treatment method The present invention provides a surface treatment method of a metal product.

Furthermore, the present invention provides a surface treatment method of a metal product that can form a coating layer, a metal coating layer, or an electrodeposition layer on a rapidly formed oxide film layer.

In order to achieve the above object, the present invention is to remove the surface of the metal product after removing the fat, to remove and neutralize the material for removing the surface of the metal product as well as to surface treatment of the washed metal product In the method of treating the surface of the metal product made of a solution, spraying the surface of the washed metal product with a mixture of ethanol (C ₂ H ₅ OH) and acetone (CH ₃ COCH ₃ ), water surface treatment solution or alcohol ; It provides a surface treatment method of a metal product comprising an oxide film layer generating step of forming an oxide layer on the surface of the metal product by burning or semi-burning the metal product treated in the solution injection step.

In addition, the surface treatment solution is a mixture of ethanol (C ₂ H ₅ OH) and acetone (CH ₃ COCH ₃ ), water, the ethanol is mixed 1 to 50 times the volume of water and the acetone 0.05 of the ethanol volume It is the solution which mixed ~ 1 times.

Furthermore, the oxide film forming step is to put the metal product treated in the solution spraying step into a loom having an internal space of 200 ~ 260 ℃ by direct weaving for 10 to 15 seconds to form an oxide film layer on the surface of the metal product In addition, the oxide film layer generating step is characterized in that the heat treatment for 5 to 20 minutes by putting the metal product treated in the solution spraying step into a heat treatment machine having an internal space of 150 ~ 200 ℃.

In addition, after washing and drying the metal product treated in the oxide film layer forming step, and forming a coating layer or an electrodeposition layer, a coating layer on the oxide film layer formed on the surface of the metal product by a painting operation or an electric coloring method, a coating method.

Thus, the surface treatment method of the metal product according to the present invention removes and washes foreign substances such as oil on the surface of the metal product, and then removes one of ethanol (C ₂ H ₅ OH) and acetone (CH ₃ COCH ₃ ) and water. Since the oxide film layer is formed on the surface of the metal product by spraying the solution or alcohols mixed on the surface of the metal product, the time required for the surface treatment by the direct or heat treatment can be very shortened. There is an advantage that the oxide film layer can be formed quickly.

In addition, by forming an electrodeposition layer on the oxide film layer formed on the surface of the metal product by the electro-coloring method to achieve colored gloss on the surface of the metal product as well as experiments by the hair-line surface treatment salt spray limit test method It was found that the surface gloss of the electrodeposition layer formed on the membrane was maintained for a long time.

Since the oxide layer formed on the surface of the metal product forms a fine pattern, it is possible to easily improve the durability of the final product in which a coating layer or a coating layer is formed on the oxide layer.

1 is an enlarged photograph of a surface of a magnesium alloy product treated by a method for treating a surface of a metal product according to the present invention.

Figure 2 is an enlarged photograph of the cross section of the magnesium alloy product treated by the surface treatment method of a metal product according to the present invention.

3 is a photograph showing an enlarged cross section of a magnesium alloy product having a coating layer formed by treating the surface of a metal product according to the present invention.

Hereinafter, a preferred embodiment of the surface treatment method of a metal product according to the present invention will be described in more detail.

The present invention is to treat the surface of a metal product, oil or oil applied to the surface of the product before the surface treatment solution or alcohols to the surface of the surface before the surface treatment with a loom or heat treatment machine having an internal space for maintaining a constant temperature after spraying the metal surface The herd will be removed.

That is, in the present invention, the surface of the metal product is removed as in the prior art, the material for removing the surface of the metal product is removed and neutralized, and the surface of the metal product washed therewith is removed.

For example, the metal product is pretreated by a degreasing step, trichloroethylene removal step, acetone neutralization step, and washing step to remove oil or splats on the surface of the product.

In the degreasing step to remove the surface of the product, the product is treated with trichloroethylene (C ₂ HCl ₃ , trichloroethylene (TCE)) solution.

For reference, trichlorethylene (C ₂ HCl ₃ , trichloroethylene (TCE)) is a colorless, clear liquid with a sweet smell.It is a degreasing cleaner for metal machine parts, drying of metal surfaces, washing and dyeing in the textile industry, and general Organic solvents used as solvents, diluents for lacquers, cleaners for glass and optical instruments, and fat removers for leather.

The trichloroethylene removes oil on the surfaces of metal products such as automobile and aircraft parts, mobile phone cases, notebook computer cases, eyeglass frames, and kitchen appliances.

In the degreasing step, the trichloroethylene attached to the surface of the product degreased with oil is removed. In the trichloroethylene removal step, the trichloroethylene solution on the surface is treated by treating the product degreased in the degreasing step with an acetone solution. To remove it.

In order to wash the acetone-treated product with water, it is necessary to neutralize the acetone on the product. In the acetone neutralization step, the acetone treated in the chlorethylene removal step is treated with methanol solution to neutralize the acetone on the surface of the product. Done.

For reference, methanol (CH ₃ OH) is the simplest alcohol, also called methyl alcohol, and is also called wood spirit because it is obtained from wood vinegar obtained by dry distillation of wood, and methyl ester type of various carboxylic acids such as salicylic acid or It is contained in various natural products as various methyl ether types.

Methanol is a colorless, transparent, volatile liquid with a distinctive aroma. It is mixed well with solvents such as water, ethanol, benzene, ether, etc., it is mixed with gasoline and used as cold fuel of automobiles. It is mixed with ethanol and modified alcohol. Also used as.

The acetone on the surface of the product is neutralized with methanol and needs to be washed. In the washing step, the product treated in the acetone neutralization step is washed with water and then dried.

In the present invention, in order to smoothly process the surface of the product before putting the product washed in the washing step in the loom or heat treatment machine, the solution injection step of spraying the surface treatment solution or alcohol to the surface of the product is carried out.

The surface treatment solution used in the solution spraying step was created as a simple substance in which water and ethanol (C ₂ H ₅ OH) and acetone (CH ₃ COCH ₃ ) were mixed. 50 times of mixing and acetone is a solution of 0.05 to 1 times the volume of ethanol.

Furthermore, in the solution spraying step, in addition to the surface treatment solution in which one of the ethanol, methanol and water are mixed, alcohols can be sprayed on the surface of the metal product, and even if the alcohol is sprayed on the surface of the metal product, the oxide film layer can be smoothly applied in the manner described below. It can be formed.

Here, ethanol not only affects flame stability and stain removal, but also lowers the surface tension of water. When ethanol is mixed with less than 1 times the water volume, the ethanol is oxidized to the surface layer of the metal product due to lack of hydroxyl group (OH-). Not only does the coating layer not be smoothly formed, but the surface treatment solution sprayed on the surface of the product is not uniformly distributed on the surface of the product due to the surface tension of water, which causes staining.

In addition, if the ethanol is mixed more than 50 times the volume of water, the oxide layer is easily formed by water, but there are many unnecessary hydroxyl groups (OH-), and the boiling point stability of water and ethanol may be lowered to form a uniform oxide layer. Adversely affects.

For reference, ethanol (C ₂ H ₅ OH) or ethyl alcohol is a colorless flammable compound and is a kind of alcohol. It exists as a colorless liquid at room temperature, and it is clear and light blue when burned. It generates flame, has a characteristic smell and taste, hydrogen bonds, melting point is -114.5 ° C, boiling point is 78.32 ° C, and it can be dissolved in water, other alcohols, ethers, ketones, chloroform, etc. Vapors are explosive and can be used as fuel in some internal combustion engines, and are often used as solvents, disinfectants, fuels, etc.

On the other hand, the acetone affects flame temperature and persistence, uniformity of ethanol firepower and shortening of the surface treatment time. When acetone is mixed less than 0.05 times the volume of ethanol, the ethanol firepower cannot be uniformed so that the thickness of the oxide layer is uniform. If the acetone is mixed with more than 1 times the volume of ethanol, the acetone may not only reduce the surface treatment time due to unnecessary amount of acetone, but also reduce the surface uniformity due to bubble generation.

For reference, acetone (CH ₃ COCH ₃ ) is mixed well with most solvents such as water, alcohol, ether, etc., and is highly flammable because of its high volatility at room temperature, and isopropyl alcohol by most reducing agents, and amalgam sodium and tetra Methylethylene glycol is produced, the reaction of sodium dichromate with sulfuric acid produces acetic acid and carbon dioxide, and reacts with ammonia to produce acetone amines such as diacetoneamine and the like.

Acetone is widely used in the manufacture of plastics and cellulose paints as one of the solvents, and is also used for dissolving and storing acetylene. It is also used as a raw material for organic synthesis, and typical compounds produced from acetone are used as solvents, thinners, etc. It is acetone alcohol, and in real life, it dissolves well in both water and organic solvents and washes substances that cannot be washed with water such as paint.

Meanwhile, an oxide film layer is formed on the surface of the product by forming an oxide layer on the product treated in the solution spraying step. The oxide film forming step burns or semi-combusts a metal product treated in the solution spraying step. An oxide film layer is formed on the surface of the film.

For example, in the anodizing step, the film is put into a loom having an internal space of 200 to 260 ° C. for 10 to 15 seconds, and when the temperature is lower than 200 ° C., the surface treatment time is not only delayed but also a product. The oxide film layer is not easily generated on the surface of the product, and if the temperature is higher than 260 ° C, the surface state of the product is not uniform.

Of course, since the heat source directly reaches the product, an oxide film is not easily generated when the weaving time is shorter than 10 seconds, and the quality of the surface of the product may be degraded when it is longer than 15 seconds.

As another example, the present invention can semi-combust the surface treatment solution or alcohols on the surface of the product by heat treatment instead of the direct treatment method as described above, which is 150 to 200 ° C. for the metal product treated in the solution injection step. The heat treatment is carried out for 5 to 20 minutes in a heat treatment device equipped with an internal space of the product. If the temperature is lower than 150 ° C., the semi-combustion state cannot be maintained, and the surface treatment time is delayed and the oxide layer is not easily formed on the surface of the product. The processing at a temperature higher than 200 ° C. does not have to waste unnecessary temperature and time since the direct processing step is more efficient.

Of course, the above heat treatment method takes more processing time than the direct fire treatment method, but the surface treatment solution or alcohol on the surface of the product can be removed more smoothly than the direct fire treatment method, and the heat treatment device indirectly reaches the product. Since the heat treatment time is less than 5 minutes, the oxide film is not easily generated, and since the surface treatment solution can be completely removed within 20 minutes, there is no need to heat-treat longer than 20 minutes.

In the present invention, the material of the metal product is magnesium alloy, aluminum and aluminum alloy, titanium and titanium alloy, iron and ferroalloy, copper and copper alloy, etc., if the magnesium alloy MgO and Mg (OH) ₂ oxide film layer is formed , Aluminum and aluminum alloys to form an oxide layer of Al ₂ O ₃ , titanium and titanium alloys to form an oxide layer of TiO ₂ , and iron and ferroalloys to form an oxide layer of Fe ₃ O ₄ ; copper and copper this alloy is Cu ₂ O oxide film layer is formed.

For example, after removing the grease on the surface of the magnesium alloy product, the substance for removing the grease on the surface of the magnesium alloy product is removed and neutralized and washed to prepare a magnesium alloy product.

In addition, when the surface treatment solution is sprayed on the surface of the magnesium alloy product in the solution spraying step, and the surface of the magnesium alloy product is burned in a direct manner in the oxide film layer producing step, as shown in FIGS. 1 and 2. It is possible to quickly form an oxide thin film layer on the surface of the product and to form an oxide film layer of a fine pattern.

For example, FIGS. 1 and 2 show an image of the surface of a magnesium product on which an oxide layer is formed. A surface treatment solution containing 20% by volume of acetone, 75% by volume of ethanol, and 5% by volume of water is added to the surface of the magnesium alloy product. After spraying, results are shown for magnesium alloy products flame treated at 250 ° C for 12 seconds.

Of course, Figures 1 and 2 is an oxide film layer formed on the surface of magnesium products, aluminum and aluminum alloys, titanium and titanium alloys, iron and alloy iron, copper and copper alloys, etc. It can be formed.

Therefore, the electrodeposited layer, the coating layer, or the coating layer, which will be described later, may be firmly formed due to the fine pattern of the oxide film layer.

In other words, after forming an oxide layer on the surface of the product as described above, the electrodeposited layer can be formed on the oxide layer by a washing drying step and an electro-coloring step. In the washing drying step, the metal treated in the oxide layer forming step After washing the product and drying it, after washing and drying the metal product, an electrodeposition layer is formed on the oxide layer by the electro-coloring step.

Of course, in the washing and drying step, it is preferable to wash using ethanol, and after washing, it is preferable to dry ethanol sufficiently.

In any case, the electro-coloring step forms an electrodeposition layer by a conventionally known electro-coloring method, as shown in FIG. 3, an electrodeposition layer by an electro-coloration method on the oxide film layer formed on the surface of the metal product treated in the washing and drying step. It is to form a, and since many known in the art it will be omitted.

Anyway in the present invention, the thickness of the electrodeposition layer of the electro-coloring step is preferably 10 ~ 24㎛, this thickness is the optimum thickness in consideration of the surface gloss, durability, processing cost, the oxide film layer is formed on the surface of the metal product, The electrodeposition layer is more uniformly formed on the oxide film layer, and the gloss may be realized on the surface of the product due to the electrodeposition layer.

In particular, the sample formed with the oxide film layer and the electrodeposition layer formed on the surface of the product was tested for 500 hours at intervals of 24 hours by the hair-line surface treatment salt spray limit test method. As a result, the surface gloss of the electrodeposited layer formed on the surface of the metal product was measured. It was found that a good state was maintained.

On the other hand, the product treated in the solution spraying step to form an oxide film layer in the oxide film layer production step, and then sequentially treated in the washing and drying step and the coating step to form a coating layer on the oxide film layer.

After forming an oxide film layer on the surface as described above, in the washing and drying step, the metal product treated by the anodized layer fish step is washed and dried, and after washing and drying the metal product in the washing and drying step, coating The work forms a coating layer on the oxide film layer formed on the surface of the metal product.

For example, coating works include baking coating, Teflon coating, ceramic coating, powder coating, and the like, and the coating step of forming a coating layer on the oxide film layer by such coating operations includes forming a coating layer by a painting operation such as powder coating. Since the method such as powder coating is well known in the art, the description thereof is omitted.

Of course, in the coating step, the coating layer is formed on the oxide film layer in a powder coating method or the like by using paints such as baking series paint, epoxy road, enamel paint, and body paint.

In particular, the thickness of the coating layer is preferably formed to an optimum thickness in consideration of surface gloss and durability, processing cost, it is necessary to subdivide the coating process in consideration of the gloss and durability of the coating layer.

That is, the metal product washed and dried in the washing and drying step is placed on a conveyor, and the surface of the product is pretreated with an antistatic gun or an antistatic nozzle, and then coated with a undercoat to improve corrosion resistance. Top coat is applied by top coat painting to increase durability. Secondly, after indirect drying, it is polished by a clear process, and the paint of the coating layer formed on the surface of the product is completely dried.

Then, the paint constituting the coating layer is firmly attached due to the oxide film layer having a fine pattern formed on the surface of the metal product, thereby increasing the durability of the coating layer. The durability of the coating layer is increased due to the fine pattern of the oxide film layer. It can be.

On the other hand, after washing and drying the product in the washing and drying step to form a metal coating layer on the oxide film layer by a dry coating method.

That is, the dry coating method includes an electron beam deposition method, an ion plating method, a sputtering method, and a plasma-enhanced chemical vapor deposition (PECVD) method, and the dry coating step of forming a metal coating layer on the oxide film layer using such a dry coating method. The coating layer is formed by a dry coating method such as a conventionally known sputtering method, such as aluminum (Al), tin (Sn), titanium (Ti), copper (Cu), gold (Au), silver (Ag), nickel Any one of (Ni), stainless steel (SUS), and silicon (Si) is formed as a coating layer by a dry coating method, and dry coating methods such as sputtering methods are well known in the art, and thus description thereof will be omitted.

Of course, in the dry coating step, aluminum (Al), tin (Sn), titanium (Ti), copper (Cu), gold (Au), silver (Ag), nickel (Ni), stainless steel (SUS), silicon (Si) ) Can select two or more metal coating layers in multiple layers on the oxide film layer by a dry coating method, or various patterns of metal of different materials, respectively, the thickness of the metal coating layer is the surface gloss and durability, processing cost It is preferable to form the optimum thickness in consideration of.

Thus, in the present invention, not only the oxide film layer having a fine pattern can be formed quickly, but also the durability of the coating layer can be increased due to the fine pattern of the oxide film layer, and the metal texture and visualization of other materials of the product due to the coating layer of the product. Can be implemented smoothly.

Claims

In the surface treatment method of the metal product which removes and maintains the surface of the metal product, and removes and neutralizes the substance for removing the surface oil of the metal product, and surface-treats the metal product which wash | cleaned it,

A solution spray step of spraying a surface treatment solution or alcohol mixed with water and ethanol (C 2 H 5 OH) and acetone (CH 3 COCH 3 ) on the surface of the washed metal product;

And an oxide film layer generating step of forming an oxide layer on the surface of the metal product by directly or indirectly heating the metal product treated in the solution spraying step.

Surface treatment method of a metal product comprising a.
The method of claim 1,

The surface treatment solution of the solution spraying step is a mixture of ethanol (C 2 H 5 OH) and acetone (CH 3 COCH 3 ), water, the ethanol is mixed with 1 to 50 times the volume of water and the acetone to ethanol Surface treatment method of a metal product, characterized in that the solution is a mixture of 0.05 to 1 times the volume.
The method of claim 1,

In the oxide film forming step, the metal product treated in the solution spraying step is put into a loom having an internal space of 200 to 260 ° C. and fired for 10 to 15 seconds to form an oxide layer on the surface of the metal product. Surface treatment method of metal products.
The method of claim 1,

The oxide film layer production step is a metal product surface treatment method characterized in that the heat treatment for 5 to 20 minutes by putting the metal product treated in the solution spraying step into a heat treatment machine having an internal space of 150 ~ 200 ℃.
The method of claim 1,

A washing and drying step of washing the metal product treated in the oxide film layer generation step with ethanol and then drying it;

And an electro-coloring step of forming an electrodeposition layer on the oxide film layer formed on the surface of the metal product treated in the washing and drying step by electro-coloring.
The method of claim 1,

A washing and drying step of washing the metal product treated in the oxide film layer generation step and then drying the metal product;

And a coating step of forming a coating layer on the oxide film layer formed on the surface of the metal product treated in the washing and drying step by a painting operation.
The method of claim 1,

A washing and drying step of washing the metal product treated in the oxide film layer generation step and then drying the metal product;

And a dry coating step of forming a coating layer by a dry coating method on the oxide film layer formed on the surface of the metal product treated in the washing and drying step.