Shrink film is created through a systematic process that turns polymer into a diverse packaging option.
Let’s look at the steps involved in making this useful packaging material.
About shrink film
Shrink film, sometimes referred to as shrink wrap, is a versatile packaging material that is widely utilized in a variety of sectors.
It acts as a protective seal, guaranteeing the packaged contents’ integrity during storage and transportation. Its use is widespread due to its low cost and ease of implementation.
How is shrink film made?
Extruding the polyethylene resin, chilling and orienting the film, and then exposing it to heat to shrink it snugly around the article are all steps in the manufacturing process.
1.Materials:
PE (polyethylene): Polyethylene, a thermoplastic polymer, is the primary component of shrink film.
Polyethylene is divided into two types: high-density polyethylene (HDPE) and low-density polyethylene (LDPE), both of which are used to make shrink film.
2.Steps:
Extrusion:
Extrusion is the first step in the production of shrink film. An extruder melts the polyethylene resin and forms it into a continuous sheet or film. A hopper, barrel, screw, and die comprise the extruder. The polyethylene resin is fed into the hopper and gradually melted inside the barrel by heat and pressure. After that, the molten resin is driven through the screw and die to make a flat, continuous film.
Cooling and Orientation:
After the film is extruded, it is chilled and solidified in a cooling process. This aids in the stabilization of the film and the prevention of distortion.
The film enters the orienting stage after cooling. Using specialist equipment, the film is stretched in both the machine direction (MD) and the transverse direction (TD) in this step.
Stretching the polymer chains aligns them and enhances the mechanical qualities of the film, such as tensile strength and puncture resistance.
Heat Treatment and Slitting:
Following orienting, the film is heat treated to shrink it to the required proportions. Typically, this is accomplished by passing the film through a heated tunnel or using a heat gun.
Because of the heat, the film shrinks and conforms tightly to the shape of the article it wraps around.
After shrinking, the film can be slit into smaller rolls or sheets, depending on the desired purpose.
The final word
shrink film production encompasses the extrusion of polyethylene resin, cooling and orientation of the film, shrinking heat treatment, and the option of slicing into smaller rolls or sheets.
Keep in mind that the process necessitates the use of specialist equipment such as extruders, cooling systems, orienting equipment, heat tunnels or guns, and slitting machines.
