The first stage of the production process is the preparation of the raw materials. The two layers of the cans are made of polypropylene resins, which are melted and extruded through a nozzle. The first layer is usually made of a recycled PP resin, which provides the necessary structural support, while the second layer is made of a virgin or high-quality PP resin, which gives the can its final appearance.

Once the two layers are extruded, they are immediately cooled to prevent deformation and ensure uniform thickness. The two layers are then laminated together using an adhesive, which binds them together and ensures the stability of the container.

Next, the cans are formed into their desired shape using a molding process. This process involves heating the two-layer film until it becomes pliable and then molding it into the desired shape using a mold. The mold is pre-designed to ensure that the final product is of the correct size and shape.

After molding, the cans are cooled and trimmed to remove any excess material. The cans are then subjected to rigorous quality control tests to ensure that they are free of any defects and meet the required specifications.

Lastly, the cans are decorated with labels or sleeve wraps to enhance their appearance and provide additional branding options. The final product is then packaged and shipped to customers.

In conclusion, the production process of double-layer PP plastic cans involves several stages that ensure the final product's desired characteristics such as durability, heat resistance, and lightweight. The process is carefully designed to ensure that the cans meet the necessary quality control standards and are free of defects. The resulting containers provide a cost-effective and sustainable packaging solution for various industries.