Anodizing process of lipstick aluminum tube for cosmetic packaging
To make the products personalized, most molded cosmetic packaging products need surface coloring treatment. The surface treatment processes of cosmetic packaging materials are diverse. Here we mainly introduce several common processes in the cosmetic packaging industry, such as vacuum coating, spraying, electroplating, anodizing, injection molding, and color modification. In this paper, we briefly describe the process of anodic oxidation.
The anodic oxidation process refers to the formation of oxide film on the surface of metal or alloy parts by electrolysis. Metal oxide film changes the surface state and properties, such as surface coloring, improving corrosion resistance, enhancing wear resistance and hardness, protecting the metal surface, and so on.
The anodic oxidation process can increase the corrosion resistance, hardness, wear-resistance, and decoration of the products, not only protecting the luster of the polished surface, but also dye and color, to obtain and maintain a rich and colorful appearance, electrical insulation, transparency, and functionality.
system composition
1.Anodizing equipment
2.Aluminum: the chemical property of aluminum is active. A dense oxide film with a thickness of about 5nm is immediately formed on the surface of aluminum in dry (lack of moisture) air so that aluminum will not be further oxidized and can resist water; When the aluminum powder is mixed with air, it is very easy to burn; Molten aluminum can react violently with water, and can reduce many metal oxides to corresponding metals at high temperature; Aluminum is amphoteric and soluble in both strong alkali and dilutes acid.
Lipstick is no different from lipstick in appearance. However, in recent years, new lipstick products have been innovated. Some of them adopt extrusion design, and some of them need to be painted on the lips by hand. Aluminum has good corrosion resistance in the atmosphere, but the strength of pure aluminum is low. All kinds of aluminum alloys that can be used as structural materials can be obtained only by alloying.
Oxide film: the oxide film of aluminum and its alloys after oxidation treatment High porosity, strong adsorption capacity, and easy dyeing The dyeing method is to put the anodized parts into the aqueous solution of organic dyes for dyeing or electrolytic coloring.
technological process
1.Process: aluminum substrate - > wire drawing - > sand blasting - > degreasing - > anode - > water cleaning - > coloring - > hole sealing - > dryer - > anode products.
2.Relevant description
Aluminum: aluminum alloy is characterized by low density and high strength. The density of aluminum is 2.7g/cm3. High plasticity, good conductivity, and corrosion resistance.
Degreasing: remove the greasy dirt and impurities on the surface of the processed products, as well as the scratches, metal burrs, and metal oxides on the surface of the products, to lay a good foundation for anodizing and coloring and make its luster meet the requirements of customers.
Chemical polishing: soaking the workpiece in phosphoric acid-based solution to eliminate the mechanical defects on the surface of the workpiece, reduce the surface roughness and improve its surface gloss. Cosmetics packaging materials: generally, cosmetics manufacturers will provide drawings or general requirements, which will be completely produced by the packaging materials manufacturers, while some packaging materials need to be divided into more subtle and more specific conditions and needs. They are divided into local printing, bottle cap packaging materials, and bottle body packaging materials. According to the different types of cosmetic packaging, some small accessories can also be outsourced.
Anodizing: the principle of aluminum anodizing is essentially the principle of water electrolysis. When the current passes through, hydrogen is released on the cathode; On the anode, the precipitated oxygen is not only molecular oxygen but also atomic oxygen and ionic oxygen, which are usually expressed as molecular oxygen in the reaction. As an anode, aluminum is oxidized by the oxygen precipitated on it to form an anhydrous alumina film.
Dyeing: the chemical coloring of the aluminum anodic oxide film is based on the ability of porous film to adsorb dyes like textile fibers. Lipstick is no different from lipstick in appearance. However, in recent years, new lipstick products have been innovated. Some of them adopt extrusion design, and some of them need to be painted on the lips by hand. Generally, the pore diameter of the anodic oxide film is 0.01-0.03 μ m. The diameter of the dye is 0010-0030.5 in water μ m. During coloring, the dye is adsorbed on the pore surface, diffused and accumulated into the pore, and combined with alumina by ion bond and hydrogen bond to color the film. After sealing the pore, the dye is fixed in the pore.
Sealing: sealing the micropores of the anodic oxide film and fixing the dyes in the micropores is an integral part of the dyeing process. The simplest way to seal the hole is to treat it in boiling water. As long as it is carried out properly, it can not only ensure that the dyeing film shows its due color firmness but also make the workpiece have the ability to prevent grease marks, color spots, and grease. Only when the anodized surface is fully sealed can it lose the ability to affect the contact.
In cosmetic packaging materials, metal accessories often exist as external components of products. For example, in the metal components of a lipstick tube, cosmetic tool components, outer components of the bottle cap, etc. the oxidation process not only increases the beauty of metal components but also protects the time tolerance of metal components.
