KR20190135090A - Nikel-free sealing treatment of aluminium anodizing - Google Patents

Abstract

An anodizing process allows an oxidative film to be made in an electrochemical manner by using aluminum as an anode to produce a film which is physically and chemically stable, has excellent corrosion resistance, beautiful appearance, and great sheen, and is possible to be dyed in various colors according to the selection of dyes for universal use in the industry. However, because, in the process, nickel, which causes allergies to the human body, is used as a processing agent, development of an alternative and a processing technology which are not inferior to a nickel acetate sealer in test performance is urgently needed, and a sealing process of a nickel-free type, which is harmless to the human body, is required. Therefore, the present invention relates to a manufacturing method of an eco-friendly aluminum anodic oxidation nickel-free sealer, which can be processed at the room temperature of 20-30°C as for the working environment, and does not cause failure such as decolorization, and more specifically, to a manufacturing method, which is characterized by an anodizing process which does not use nickel salt.

Description

Nickel-free sealing treatment of aluminum anodizing

The present invention relates to nickel-free pre-sealing and sealing treatment of aluminum anodizing products. In the past, the present invention seeks a sealing agent that guarantees the discoloration and corrosion resistance of dyes as nickel oxalic sealant containing nickel, a representative skin allergen. It was difficult.

Therefore, titanium (Ti), zirconium (Zr), tungsten (W), and trivalent chromium have strong corrosion resistance as a pre-sealing property to prevent discoloration of dyes during anodizing nickel-free sealing process and to ensure reliability as a nickel-based sealing agent. The primary sealing film layer is formed using a secondary sealing, and zinc (Zn), cerium (Ce), lithium (Li) magnesium (Mg), manganese (Mn), molybdenum (Mo), trivalent chromium (CrO3) Sealing treatment method characterized by using a metal such as to increase the color fading and corrosion resistance of the colored product.

The present invention is a Nikel-free Sealing process of aluminum anodizing products that do not contain nickel (Ni), which is a skin allergen, and has an appearance such as powder scattering, cloudiness, and rainbow colors generated during conventional aluminum anodizing boiling water sealing. It is a breakthrough in that it is a sealing agent that solves quality problems and does not contain allergen nickel (Ni).

In general, when anodizing produces an oxide film, a rectangular small hole is formed. If the hole is fine and left as it is, corrosion may continue and oil stains or stains are easily burned. To eliminate this, seals should be made to close the holes in the coating surface.

Sealing treatment methods are divided into nickel-cutting, sealing by boiling water, sealing by vapor pressure, sealing by resin, sealing by metal salt, sealing by painting, and the like.

Previously, when nickel saxane was used as a sealing agent for anodizing, surface adhesion and gloss were excellent, but nickel (Ni) contained a disadvantage of not solving the problem of skin allergy. In the surface treatment industry, efforts have been made to replace nickel (Ni), which is an allergen for not only mobile products with high physical contact, but also home appliances.

In the anodizing sealing process, the nickel elution process was developed to remove the nickel (Ni) component after nickel sealing because the color of the dye is severe and corrosion resistance is not obtained without nickel (Ni).

However, it was necessary to worry about whether nickel (Ni) may remain at all times, and after the nickel (Ni) component was omitted, reliability, including salt water, became worse than that of the conventional nickel-based sealing agent.

Accordingly, zinc is a highly reliable metal to form a primary sealing film by a pre-sealing process using titanium (Ti), zirconium (Zr), tungsten (W), and trivalent chromium (CrO3) with high corrosion resistance. Fixability of dye using metals such as (Zn), cerium (Ce), lithium (Li) lithium (Li), magnesium (Mg), manganese (Mn), molybdenum (Mo), trivalent chromium (CrO3) The goal is to develop a nickel-free sealant that can increase and increase corrosion resistance.

The present invention is a drug developed for solving the allergy problem by nickel (Ni) as described above, and solves the quality problems such as dusting, scattering, color fading, etc. Ni-free sealing agent is developed for the purpose.

In addition, the nickel elution process, which was performed to remove the nickel (Ni) component, can be omitted, and thus cost reduction effect is expected.

Compared with the product which is sealed with a conventional nickel acid-based sealing agent which has excellent corrosion resistance and sealing property, it is intended to make a product that is inferior to the quality.

After sealing, we tried to make products with specifications that satisfies the company by conducting reliability tests such as color dropout, dusting and scattering, salt water, acid resistance (electric conductivity), and magic test after sealing.

The nickel-free sealing process invented to achieve the above object is largely a pretreatment step including degreasing, an anodizing step for anodic oxidation, a dye coloring step for dye coloring, and a pre-sealing for dye fixing. It is divided into the sealing step, the Nikel-free Sealing step to improve the reliability of the fixed dye, and the final drying step.

Nickel-free rods that do not use nickel in sealing devices and can perform sealing performance are commercially available by various anodization-related chemical companies, but to date, dyeing products that can replace nickel acetate are excellent in corrosion resistance and easy process management. The invention of the deduction will be in the spotlight in the future of the aluminum anodizing agent market.

There is a need for nickel-free sealing, which is harmless to the human body, and it is an environmentally friendly aluminum anodized nickel-free sealing agent (Ni-free sealer that can be processed at room temperature of 20 ~ 30 ^o C and does not have any defects such as discoloration. The invention of) is required to shorten the work process and to be environmentally friendly.

1 is a bleaching prevention anodizing process containing no nickel salt in accordance with the present invention.

This will be described in detail for each step as follows.

The pretreatment step includes a degreasing process to remove foreign substances adhering to the surface of the aluminum injection molding, a chemical polishing process to give gloss according to product specifications, and a smut process to remove smut generated during polishing.

Here, the degreasing process is composed of 10-15% weight ratio of AL CLEAN # 1000. It is used at room temperature and the deposition time is 1 ~ 3 minutes.

The chemical polishing process consists of Dia Bright SAP stock solution from the head office. Work by giving 10 ~ 15 second liquefaction time after 20 ~ 30 second deposition at 90 ~ 95 ℃.

The desmut process consists of 20-30% weight ratio of nitric acid. Work at room temperature for 1 ~ 2 minutes.

Sulfuric acid baths and oxalic acid baths are mainly used in the anodizing step of anodizing the aluminum surface to improve corrosion resistance and abrasion resistance, and to make a fine porous oxide film for dye coloring. Experiment at

Anodizing thickness is closely related to bath temperature, bath voltage, and time. The anodizing thickness was studied at 15 ~ 16 micron in anodizing thickness by mainly working around 15 ℃ for 40 minutes.

Dye coloring step is OKac's Tac Black SG (B), Tac Red BLH (102),

Swiss Clariant Sanodure Blue G is used and the temperature is 45 ~ 50 degrees.

The concentration was 2 to 5 g / L, and the coloration time was 5 to 10 minutes.

Pre-sealing step for fixing colored dyes is performed by pre-sealing using titanium (Ti), zirconium (Zr), tungsten (W), and trivalent chromium (CrO3) with high corrosion resistance. It is intended to increase the corrosion resistance and prevent color fall by forming.

The Ni-free sealing step, which enhances the reliability of fixed dyes, is a sealing process that prevents micropores made for coloring, and replaces allergens such as nickel (Ni), which has strong corrosion resistance to give color and corrosion resistance. It is a nickel-free sealing process containing metals such as (Zn), cerium (Ce), lithium (Li), magnesium (Mg), manganese (Mn) and molybdenum (Mo).

At this time, if the sealing process is not complete, color fall suppressed in the first sealing process occurs, and reliability, including saline resistance and acid resistance, is poor. In order to provide more stable sealing, metals with high corrosion resistance are added, such as acetates or sulfates of zinc (Zn), cerium (Ce), lithium (Li), magnesium (Mg), manganese (Mn) and molybdenum (Mo) metals. It is characterized by putting one of 0.5 ~ 5.0 g / L.

Surfactant Alpha-Olefin Sulfonate (CAS No.689398-4), Polyoxyethylene Sorbitan Fattyacid Ester (CAS No.p005-67-8) to remove smut and wettability ), At least one or more of Carboxy Betaine (CAS No. 683-10-3) is characterized by putting 0.1 ~ 2.0 g / L.

To meet the elevated pH, acetic acid, salicylic acid, lactic acid, tricic acid, citric acid, succinic acid, malic acid, malic acid, and sulfonic acid PH 0.1-1.0 g / L at least one of maleic acid, tarfarric acid and adipic acid is adjusted to pH 5.0-6.0,

At this time, the temperature of the nickel-free sealing process is immersion sealing at least 30 minutes at 90 ~ 95 ℃.

Anodizing thicknesses of 15 to 16 microns can be sealed for 2 minutes per micron.

Conventional nickel-free process was performed for 3 minutes per micron, but the sealing time is also reduced by the addition of a metal salt.

S10: pretreatment step S40: pre-sealing step
S20: Anodizing step S50: Ni-Free sealing step
S30: dyeing step S60: drying step

Claims (7)

 Pretreatment step including degreasing, anodizing step for anodic oxidation, dye coloring step for dye coloring, pre-sealing step for dye fixing, Nikel-free Sealing step for enhancing the reliability of the fixed dye, finishing drying step Manufacturing method of nickel-free sealing process divided into The method of claim 1, wherein the pretreatment step includes a degreasing process for removing foreign substances adhering to the surface of the aluminum injection molding, a chemical polishing process for giving gloss according to product specifications, and a smut process for removing smut generated during polishing. Here, the degreasing process consists of 10 to 15% by weight of AL CLEAN # 1000. Used at room temperature and the deposition time is 1 minute to 3 minutes. According to claim 1, wherein the chemical polishing process is composed of Dia Bright SAP stock solution of the head office. After 20 ~ 30 seconds immersion at 90 ~ 95 ℃, give 10 ~ 15 seconds liquefaction time. Dismute process is a manufacturing method composed of 20 ~ 30% weight ratio of nitric acid. In the anodizing step of anodizing the aluminum surface to increase corrosion resistance and abrasion resistance and to make a fine porous oxide film for dye coloring, sulfuric acid bath and oxalic acid bath are mainly used, but sulfuric acid 190 ~ 200g / L which is commonly used here Anodizing thickness in the bath is closely related to bath temperature, bath voltage and time. The manufacturing method is characterized by working at anodizing thickness of 15 ~ 16 microns mainly by working around 15 ℃ 40V for 21 ℃. According to claim 1, The dyeing step is used Tac Black SG (B), Tac Red BLH (102), Swiss Clariant's Sanodure Blue G from OKuno, Japan, the temperature is 45 ~ 50 degrees concentration 2 ~ 5g / L treatment time is 5 ~ 10 minutes, pre-sealing step for fixing colored dye is pre-sealing with titanium (Ti), zirconium (Zr), tungsten (W) and trivalent chromium (CrO3). Forming a primary sealing film on the surface of the aluminum colored by the process to increase the corrosion resistance and to prevent color fallout. The method of claim 1, wherein the Ni-free sealing step of increasing the reliability of the fixed dye is a step of sealing the micropores made for coloring to replace the allergen material nickel (Ni) to reduce color loss and corrosion resistance Nickel-free sealing process containing metals such as zinc (Zn), cerium (Ce), lithium (Li), magnesium (Mg), manganese (Mn) and molybdenum (Mo) to be. At this time, if the sealing process is not complete, color fall suppressed in the first sealing process occurs, and reliability, including saline resistance and acid resistance, is poor. In order to provide more stable sealing, metals with high corrosion resistance are added, such as acetates or sulfates of zinc (Zn), cerium (Ce), lithium (Li), magnesium (Mg), manganese (Mn) and molybdenum (Mo) metals. Manufacturing method characterized in that to put one of 0.5 ~ 5.0 g / L According to claim 1, Surfactants Alpha-Olefin Sulfonate (CAS No.689398-4), Polyoxyethylene Sorbitan Fattyacid Ester (CAS No. p005-67-8), Carboxy Betaine (CAS No. 683-10-3) at least one or more of the manufacturing method characterized in that the put. According to claim 1, the nickel-free (Ni-free) sealing process of the invention is largely pre-treatment step including degreasing, anodizing step for anodic oxidation, dye coloring step for dye coloring, pre-sealing for dye fixing (pre- A process for producing a nickel-free anti-pigmentation anodizing process characterized by a sealing step, a Nikel-free Sealing step for enhancing the reliability of the fixed dye, and a final drying step.

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