Aluminum tube, also known as packaging aluminum tube, aluminum tube, metal tube, is a common packaging material, which can be used to fill glue, toothpaste, hair dye, pigment, cosmetics, shoe polish and other ointment products.
The aluminum material will not rust, has good ductility and air tightness, and provides good protection for the contents. Aluminum is easy to recycle and can respond to the growing demand for green environmental protection.
The production process of aluminum tube can be roughly divided into 4 steps, as follows:
1. Aluminum sheet stamping, aluminum tube trimming, annealing
The raw material of aluminum tube is aluminum sheet with 99.7% aluminum purity. Using punching equipment, the aluminum sheet is punched into a hollow tubular shape. After the aluminum tube is stamped and formed, the nozzle and the tail of the tube must be cut evenly, and a neat thread must be repaired at the mouth of the tooth. Work hardening is easy to occur in the extrusion molding process. Therefore, it must be annealed to soften the surface hardened layer, eliminate residual stress, and normalize the crystalline particles in the organization.
2. Primer The body of the aluminum tube is usually coated with a “primer”. The primer is not a paint, but a protective polyester resin, usually white or solid color, also known as a primer. After the primer is coated, it needs to be baked and cured at 140 degrees Celsius. The purpose of priming is to form a protective film on the surface of the tube to provide cushioning for minor collisions and reduce scratches, dents and damage caused during transportation and use.
The “printing” of aluminum tubes is to provide recognition and aesthetics for products. Good printing quality can bring an intuitive sense of delicacy to aluminum tubes, so it is also the most important link. Aluminum tube printing has the difference between offset printing and silk screen printing. The more common offset printing has four-color, five-color, and six-color different equipment conditions. It also needs to be heated and dried after printing. After the printing is completed, it can be covered.
4. Tail glue
It is to spray a circle of latex near the opening inside the pipe wall, referred to as tail glue. Its function is to fill the gap at the fold when the aluminum tube is folded and sealed to improve the airtightness of the package.