KR20110075092A - Method for treating metal surface by using self-assembled monolayer, the steel sheet surface-treated by the method and the metal surface treatment solution therefor - Google Patents

Abstract

PURPOSE: A method for treating the surface of metal using a self-assembled monolayer, a steel sheet with a treated surface using the same, and a metal surface treatment solution therefor are provided to improve the properties of a metal surface. CONSTITUTION: A method for treating the surface of metal using a self-assembled monolayer is as follows. the surface of metal, composed of a galvanized steel sheet and a magnesium sheet, is organically washed. Organic solvents remained on the surface of the metal is eliminated using nitrogen gas. The surface of the metal is humidified. The metal is put into a solution which forms a self-assembled monolayer. The put metal is washed by one or more solvents. The metal is thermally hardened in a vacuum.

Description

TECHNICAL FIELD The present invention relates to a metal surface treatment method using a self-assembled molecular film, a steel sheet surface-treated by the above method, and a metal surface treatment solution used in the above method method and the metal surface treatment solution therefor}

The present invention relates to a metal surface treatment method using a self-assembled monolayer membrane, a steel sheet surface-treated by the above method and a metal surface treatment solution used in the method, and more particularly, A metal surface treatment method using a self-assembled molecular film that improves the surface characteristics by forming an aggregated molecular film, a steel sheet surface-treated by the method, and a metal surface treatment solution used in the method.

Since zinc has excellent corrosion resistance, it is used as a galvanized steel sheet by plating on a steel sheet. However, when it is used for other purposes, it is limited in paintability and other characteristics, and in case of magnesium sheet, But it has weak resistance to corrosion and other characteristics.

In the past, due to the limitations of these materials, surface treatment was performed using chromium-containing materials. However, since chromium used here is very toxic, it is a big problem in the environment and is difficult to regulate. exist.

Therefore, new surface treatment studies are needed to overcome the limitations of the methods and materials used to improve the surface properties.

Further, in order to improve such surface properties, there is known a technique using a method of improving the corrosion resistance of the self-metal through an alloy with a noble metal (Ni, Co, etc.) and improving the corrosion resistance by coating the surface of the polymer film. There is a problem that the advantage of the metal itself is lost or the price is increased.

Accordingly, the object of the present invention is to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a method of manufacturing a metal material which can improve the corrosion resistance, And a method for treating a metal surface capable of strongly attaching molecules to a metal surface at a low cost.

Another object of the present invention is to provide a steel sheet surface-treated by the above method.

Another object of the present invention is to provide a metal surface treatment solution used in the above method.

According to one aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: organically cleaning a surface of a metal made of at least one of a galvanized steel sheet and a magnesium sheet; Removing the organic solvent remaining on the surface of the metal with nitrogen gas; Humidifying the surface of the metal; Wherein the metal is at least one compound having at least one self-assembling property selected from the group consisting of silane series, alkane series acid and phosphoric acid series components, and at least one solvent selected from toluene, benzene, ethanol, n-butanol, n- Immersing the solution to form a self-assembled molecular film; Washing the immersed metal into at least one solvent selected from the group consisting of toluene, benzene, ethanol, n-butanol, n-heptanol and isopropanol; And heat-treating the metal under vacuum at 100-200 占 폚 to cure the metal surface.

According to another aspect of the present invention, there is provided a steel sheet surface-treated by the above method.

According to another aspect of the present invention, there is provided a process for the production of at least one component selected from the group consisting of silane series, alkane series acid and phosphoric acid series component and at least one solvent selected from toluene, benzene, ethanol, n-butanol, n-heptanol and isopropanol A metal surface treatment solution for forming a self-assembled molecular film composed of a metal surface treatment solution is provided.

According to the metal surface treatment method of the present invention, a self-assembled monolayer film is formed on the surface of a galvanized steel sheet or a magnesium sheet, and such a self-assembled monolayer film can improve the characteristics of the metal surface. According to the method of the present invention, it is possible to provide a galvanized steel sheet and a magnesium sheet which have improved surface characteristics such as being usable as an adhesive layer for adhesion with a layer of corrosion resistance, transparency and other materials.

In addition, the method of the present invention is environment-friendly as a chrome-free surface treatment method.

Self-assembled Monolayer (SAM) is a molecule that is formed by spontaneous formation of a surfactant by adsorption to a substrate in a solution containing an organic solvent and a surfactant. The molecules forming the self-assembled monolayer It consists of three components as follows.

The first part is the active head group, which causes chemical adsorption on the surface of the solid sample. Through this process, the head group forms a chemical bond with the substrate surface and the organic molecules are densely placed on the surface of the sample. These chemical bonds may also have covalent, coordination, or ionic properties.

The second part is the alkyl chain. In terms of energy, the interchain attraction is a van der Waals interaction of less than 10 kcal / mol. Therefore, the formation of the self-assembled molecular film is achieved through the chemical bonding of the head group and the subsequent interaction of the alkyl chain.

The third part is the surface group, which is exposed on the surface. These end functional groups determine the physicochemical properties of the self-assembled monolayer. The simplest functional group is the methyl group, but several different groups can be used to impart specific functions to the membrane.

When the self-assembled molecular film having the above properties is used for the surface treatment for improving corrosion resistance, the advantage is that the self-assembled molecular film is coated with a monolayer so that the molecules are strongly adhered to the metal surface And it is possible to change the characteristics of the metal surface according to the selection of the end functional group of the self-assembled molecular membrane molecule regardless of the shape or roughness of the metal surface.

The inventors of the present invention have conducted intensive studies and have found that, after a surface pretreatment process in which an oxide film and a hydroxide film are formed on a surface by wetting a galvanized steel sheet and a magnesium sheet differently from each other, It is possible to improve the corrosion resistance by self-assembled monolayer surface treatment in a short time by comparing the corrosion resistance of each condition by adjusting the solution concentration and immersion time at the surface of the coated steel sheet and the magnesium sheet. And can be used as an adhesive layer of another material layer, thereby completing the present invention.

The method for improving the surface characteristics according to the present invention is a method for improving the surface characteristics, comprising the steps of moistening a galvanized steel sheet and a magnesium sheet to produce an oxide film and a hydroxide film on the surface thereof and then forming a silane series, alkanoic acid, A surface treatment is carried out using a compound.

FIG. 1 schematically shows a metal surface treatment method of the present invention.

According to the method of the present invention, first, the surface of the metal made of at least one of the galvanized steel sheet and the magnesium sheet is subjected to the organic washing. At this time, the organic washing is not particularly limited, but it is preferable that the organic washing is carried out by immersing the metal in each solvent in the order of acetone, ethanol, and isopropanol followed by ultrasonic treatment.

Then, the organic solvent remaining on the surface of the organic washed metal is removed with nitrogen gas, and then the surface of the metal is subjected to a humidifying treatment. At this time, the humidifying treatment condition is not particularly limited, but it is preferable that the humidifying treatment is performed for at least 10 hours under at least 80% humidity. More preferably, it is humidified for 20-30 hours under a humidity of 80-100%. By this humidification treatment, an oxide film and an oxide film are sufficiently formed on the surface of the metal. The oxide film and the oxide film enable the formation of the self-assembled monolayer, and the more homogeneously the film is formed, the more uniformly the self-assembled monolayer is formed on the surface.

Then, the humidified metal is immersed in a solution forming a self-assembled monolayer in which a compound having at least one self-assembling property selected from a silane series, an alkane series acid and a phosphoric acid series component is dissolved. The solution for forming the self-assembled molecular film is preferably a solution containing at least one selected from the group consisting of octadecyltrichlorosilane, butyltrichlorosilane, 3-chloropropyltrichlorosilane, 3-bromopropyltrichlorosilane, trichloro (3,3,3- Perfluorooctyl-trichlorosilane, phenethyltrichlorosilane, 4- (chloromethyl) phenyl trichlorosilane, 2- (4-chlorosulfonylphenyl) But are not limited to, ethyl trichlorosilane, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, A compound having at least one self-assembling property selected from 1,11-undecandicarboxylic acid, methylphosphonic acid, phenylphosphonic acid, octadecylphosphonic acid and 3-mercaptopropionic acid is present in a concentration of 0.01 to 20 mM . If the concentration of the compound having the self-assembling property is less than 0.01 mM, the rate of formation of the self-assembled monolayer is very slow on the surface, and the formed self-assembled monolayer is not uniform. When the concentration is more than 20 mM, the concentration becomes too high to form a self-assembled monolayer on the surface and react with the byproducts formed on the surface and the self-assembled monolayer, resulting in poor surface characteristics.

It is preferable that at least one solvent selected from toluene, benzene, ethanol, n-butanol, n-heptanol, and isopropanol is used as a solvent for the compounds in the solution forming the self-assembled molecular membrane.

The condition for the immersion treatment is not particularly limited, but it is preferably carried out at -10 캜 to 60 캜 for 1 second to 30 minutes. When the immersion treatment is carried out at a temperature lower than -10 ° C, the formation of the self-assembled monolayer takes a very long time. When the immobilization is carried out at a temperature higher than 60 ° C, The self-assembled molecular film is not formed on the surface if the treatment time is too short, and if the treatment time exceeds 1 minute, the self-assembled molecular film is not formed on the surface. And at the same time, it reacts with the byproducts generated when the surface and the self-assembled molecular film are formed, and the surface properties are not good, which is not preferable.

Then, the immersed metal is taken out and washed with a solvent. At this time, the solvent used for washing is not particularly limited, but it is preferable to use at least one solvent selected from the group consisting of toluene, benzene, ethanol, n-butanol, n-heptanol and isopropanol.

Finally, the cleaned metal is finally cured by heat treatment under vacuum. The temperature for the heat treatment may be 100-200 deg. C, preferably 120-180 deg. C, and the time is preferably 1-30 min.

The corrosion resistance of the zinc-plated steel sheet or the magnesium plate can be improved in a relatively short time by treating the metal surface with the self-assembled molecular film as in the present invention, and at the same time, And can be used as an adhesive layer.

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the examples described.

Example

Example 1 - Surface treatment of galvanized steel sheet and magnesium sheet

Before surface treatment, organic solvents were cleaned by ultrasonic treatment in acetone, ethanol and isopropanol in order of acetone, ethanol and isopropanol in order to remove impurities on the surfaces of galvanized steel sheet and magnesium sheet for 15 minutes. Then, the organic solvent remaining on the surface of the metal was removed with nitrogen gas. Then, the metal was allowed to stand for 24 hours under a humidity of 80% to be humidified.

On the other hand, octadecyltrichlorosilane (OTS) was used as a material to form a self-assembled molecular film, and toluene was used as a solvent to prepare a self-assembled molecular film solution. The metal was immersed in the prepared self-assembled monolayer solution to perform surface treatment. At this time, the surface treatment temperature was room temperature, the solution concentration was varied from 0.1 to 2 mM, and the immersion time was varied from 1 second to 5 minutes. After immersion treatment, the substrate was washed with toluene as a solvent to remove foreign matters. Then, after the surface treatment, the galvanized steel sheet and the magnesium sheet having the self-assembled monolayer were placed in a vacuum oven and thermally cured at 150 ° C for 10 minutes.

Example 2 - Surface analysis of metal sheet after humidification

In Example 1, a galvanized steel sheet was allowed to stand under a humidity of 80% for 24 hours and then subjected to a humidifying treatment. Thereafter, an X-ray photoelectron (XPS) and an auger electron spectrometer And the surface was analyzed. The results are shown in Fig. As can be seen from FIG. 2, when Zn2p and O1s as the XPS results are examined, it can be seen that Zn (OH) ₂ and ZnO are sufficiently generated in the surface state, and Zn _LMN , which is the result of AES, (OH) ₂ and ZnO are sufficiently generated.

In Example 1, the surface of the magnesium plate was subjected to a humidification treatment by keeping it at a humidity of 80% for 24 hours, and then the surface of the magnesium plate was analyzed using an X-ray photoelectron (XPS) . The results are shown in Fig. As can be seen from FIG. 3, when Mg2p and O1s as XPS results are examined, it can be confirmed that Mg (OH) 2 and MgO are sufficiently generated.

In addition, the XPS results of FIGS. 2 and 3 show the composition of the oxide film and the oxide film on the surface through the widths of the respective peaks are shown in Table 1.

[Table 1]

Board Sputter time Zn (OH) 2 Zn, ZnO GI 0s (surface)
600s 82.9%
62.6% 17.1%
37.4% Board Sputter time Mg (OH) ₂ MgO Mg 0s (surface)
1200s 100%
32% 0%
68%

As can be seen from the above Table 1, it can be seen that the magnesium plate is composed of only an oxide film of Mg (OH) ₂ as compared with the galvanized steel sheet to have a more uniform surface, It is considered to affect the formation of the caption and improve the corrosion resistance of the surface.

Example 3 - Surface analysis of metal sheet after surface treatment (after immersion treatment)

The surface of the metal sheet was analyzed by Fourier transform infrared spectroscopy (FT-IR) in order to investigate whether a self-assembled monolayer was formed on the surface after immersing the metal sheet in Example 1 and completing the surface treatment. As a result of the test, the results for the galvanized steel sheet and the magnesium sheet were the same, and the results of the galvanized steel sheet were shown in FIG. On the left side of FIG. 4, the immersion time was fixed at 1 second and the immersion time was fixed at 5 minutes. As can be seen from FIG. 4, when the sample is immersed for 1 second at a concentration of 2 mM and the peak of the sample is immersed for 5 minutes at all concentrations, a complete self-assembled monolayer is formed on the surface even if immersed for only 1 second at 2 mM And the same results were obtained for the galvanized steel sheet and the magnesium sheet.

Also, in order to investigate whether a self-assembled molecular film was formed on the surface, it was confirmed whether a self-assembled molecular film was formed using a contact angle, and the result is shown in FIG. As can be seen from FIG. 5, the results were the same as those of the FT-IR analysis, and it was confirmed that complete self-assembled molecular films were formed on the surface even when immersed for only 1 second at 2 mM.

Example 4 - Corrosion resistance test

A salt spray test (5% NaCl solution) was conducted to examine the corrosion resistance of the galvanized steel sheet and the magnesium plate surface-treated in Example 1, and the results are shown in FIG. The left side is the pre-test image, and the right side is the post-test image. As can be seen from FIG. 6, before and after the test, it was confirmed that the corrosion resistance was improved in both of the zinc-coated steel sheet and the magnesium sheet, but the corrosion resistance of the zinc-coated steel sheet was slightly lower than that of the magnesium sheet , The results are illustrated in Figures 2 and 3 and in Table 1. That is, it is explained that the magnesium plate is more uniform in surface than the galvanized steel sheet, and the self-assembled monolayer membrane, which is a corrosion resistant membrane, is formed more densely and has more excellent corrosion resistance.

The results of the salt spray test are shown in Table 2 below.

[Table 2]

Whether surface treatment Surface untreated
(Comparative Example) Surface treatment sample Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Sample 7 Sample 8 Immersion treatment conditions Untreated 0.1 mM
1 second 0.1 mM
1 minute 0.1 mM
5 minutes 0.5 mM
1 second 0.5 mM
1 minute 0.5 mM
5 minutes 2 mM
1 second Salt water spray test result GI 0.5 hours 0.8 hours 2 hours 5.5 hours 1 hours 2.1 hours 6 hours 5.7 hours Mg 0.5 hours 1 hours 2.2 hours 7.2 hours 1.5 hours 3 hours 7.5 hours 7.3 hours Corrosion resistance evaluation × × △ ○ × △ ○ ○

* In salt spray test, corrosion resistance is classified into three grades as follows. ×: 0-2 hours, Δ: 2-5 hours, ○: 5-8 hours

As can be seen from the above Table 2, it can be seen that the samples which were surface-treated according to Example 1 are superior in corrosion resistance to the sample 1 which is the non-surface treated comparative sample, and the samples 2-8 according to Example 1 have the same It can be confirmed that the corrosion resistance is improved as the immersion time is increased. Particularly, when the sample 8 is examined, the corrosion resistance is improved by the immersion treatment for a short period of time. Thus, according to the method of the present invention, it is confirmed that the corrosion resistance is improved through the surface treatment in a short time.

The Nyquist impedance plot was obtained by analyzing the galvanized steel sheet and the magnesium plate surface-treated in Example 1 by EIS (Electrochemical Impedance Spectroscopy) in order to investigate the corrosion resistance. The results are shown in FIG. 7 Respectively. In addition, the efficiency (PE) for corrosion resistance was calculated through the radius obtained from the Nyquist impedance plot of FIG. 7, and the results are shown in Table 3. 7 is a graph when the surface treatment is not performed on the left side, and a graph when the surface treatment is performed on the right side. Corrosion resistance means the radius of a semicircle in the graph, which means that the larger the radius, the greater the corrosion resistance. In Table 3, Rt is a result of the corrosion resistance test without the surface treatment, and Rsam is the corrosion resistance test result after the surface treatment according to the present invention.

[Table 3]

Board Condition Rt (Ω · cm 2) Condition Rsam (Ω · cm 2) Corrosion resistance efficiency
(PE) (%) GI Bare 3.7 x 10 ³ 0.1 mM, 5 min 3.75 x 10 ⁴ 90.1 2mM, 1 sec 4.0 × 10 ⁴ 90.8 Mg Untreated 4.5 x 10 ³ 0.1 mM, 5 min 1.25 × 10 ⁵ 96.4 2mM, 1 sec 1.3 x 10 ⁵ 96.5

As can be seen from FIG. 7 and Table 3, it was confirmed that the corrosion resistance was improved in both the galvanized steel sheet and the magnesium sheet, but it was found that the galvanized steel sheet had a lower corrosion resistance than the magnesium sheet, 3, and the results shown in Table 1 and the result in FIG. 6, it can be seen that the magnesium plate is more uniform in surface than the galvanized steel sheet, and the self-assembled monolayer membrane, which is the corrosion resistant membrane, ≪ / RTI >

1 schematically shows a metal surface treatment method of the present invention.

Fig. 2 shows the result of surface analysis using an X-ray photoelectron (XPS) and an auger electron spectrometer (AES) after a galvanized steel sheet is subjected to a moistening treatment.

Fig. 3 shows the result of surface analysis using XPS after humidifying the magnesium plate material.

FIG. 4 is a graph showing the results of surface analysis of a metal sheet using FT-IR (Fourier-transform infrared spectroscopy) after surface treatment according to the method of the present invention.

FIG. 5 shows the result of analyzing the surface of a metal sheet using a contact angle after surface treatment according to the method of the present invention.

Fig. 6 shows the result of performing a salt spray test (5% NaCl solution) to examine the corrosion resistance of a metal sheet subjected to surface treatment according to the method of the present invention.

FIG. 7 is a graph showing the results of an EIS (Electrochemical Impedance Spectroscopy) analysis for examining the corrosion resistance of a surface-treated metal sheet according to the method of the present invention.

Claims (9)

Organic cleaning of a surface of a metal comprising at least one of a galvanized steel sheet and a magnesium sheet; Removing the organic solvent remaining on the surface of the metal with nitrogen gas; Humidifying the surface of the metal; Wherein the metal is at least one compound having at least one self-assembling property selected from the group consisting of silane series, alkane series acid and phosphoric acid series compound, and at least one solvent selected from toluene, benzene, ethanol, n-butanol, n-heptanol and isopropanol Immersing the solution to form a self-assembled molecular film; Washing the immersed metal into at least one solvent selected from the group consisting of toluene, benzene, ethanol, n-butanol, n-heptanol and isopropanol; And Thermally curing the metal under vacuum A metal surface treatment method using the self-assembled molecular film. The method according to claim 1, wherein the organic cleaning is performed by immersing the metal in the order of acetone, ethanol and isopropanol, followed by ultrasonic treatment. The method according to claim 1, wherein the humidifying treatment is performed for at least 10 hours under at least 80% humidity. 2. The method according to claim 1, wherein the solution forming the self-assembled molecular film is selected from the group consisting of octadecyltrichlorosilane, butyltrichlorosilane, 3-chloropropyltrichlorosilane, 3-bromopropyltrichlorosilane, trichloro , 3-trifluoropropyl) silane, 1H, 1H, 2H, 2H-perfluorooctyl-trichlorosilane, phenethyltrichlorosilane, 4- (chloromethyl) phenyltrichlorosilane, 2- Octanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, 12-amino dodecanoic acid, A compound having at least one self-assembling property selected from among succinic acid, carnaic acid, 1,11-undecandicarboxylic acid, methylphosphonic acid, phenylphosphonic acid, octadecylphosphonic acid and 3-mercaptopropionic acid is added to the solvent in an amount of 0.01 to 20 mM ≪ / RTI > by weight. The method according to claim 1, wherein the dipping treatment is performed at -10 ° C to 60 ° C for 1 second to 30 minutes. A steel sheet surface-treated by the method according to any one of claims 1 to 5. The steel sheet according to claim 6, wherein the metal is a galvanized steel sheet or a magnesium steel sheet. At least one compound selected from silane series, alkane series acid and phosphoric acid series components and at least one solvent selected from toluene, benzene, ethanol, n-butanol, n-heptanol and isopropanol Metal surface treatment solution. The method of claim 8, wherein the solution is selected from the group consisting of octadecyltrichlorosilane, butyltrichlorosilane, 3-chloropropyltrichlorosilane, 3-bromopropyltrichlorosilane, trichloro (3,3,3- ) Silane, 1H, 1H, 2H, 2H-perfluorooctyl-trichlorosilane, phenethyltrichlorosilane, 4- (chloromethyl) phenyltrichlorosilane, 2- (4- chlorosulfonylphenyl) ethyl trichloro Silane, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidonic acid, Characterized in that a compound having at least one self-assembling property selected from undecandicarboxylic acid, methylphosphonic acid, phenylphosphonic acid, octadecylphosphonic acid and 3-mercaptopropionic acid is present in a concentration of 0.01 to 20 mM. Surface treatment solution.

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