Shrink wrap, also shrink film, is a material made up of plastic film that is shrunk onto an object by heat. This heat is applied either with a handheld heat gun (electric or gas), or the product and film can pass through a heat tunnel on a conveyor. Shrink wrap packaging helps to protect the product by tightly enclosing it to form a sealed, tight-fitting package. Shrink wrap is inexpensive, easily applied, and UV protected for long-term usage thus protecting against weather damage while being stored or transported.
With a variety of shrink wrap materials available, the three main wraps used in shrink packaging material for protecting and securing products are polyvinyl chloride (PVC), polyolefin (POF), and polyethylene (PE). Each wrap material has different capabilities and characteristics that make them suitable for specific applications. The most commonly used shrink wrap is polyolefin and is available in a variety of thicknesses, clarities, strengths, and shrink ratios.
Although polyvinyl chloride (PVC) due to its durability, lightweight and inexpensive properties is quite popular, it has been banned in many countries, due to the harmful products created by its decomposition. If used, it should be handled in a well-ventilated area, as it can give off a strong, harmful odour. The entire PVC lifecycle from its production, use, and disposal results in the release of toxic, chlorine-based chemicals. These toxins enter into the water, air, and soil causing severe health problems like cancer, immune system damage, and hormone disruption. PVC leaves carbon deposits, has very poor heat stability, and is not good for bundling.
Polyolefin (POF) is extremely durable, versatile, puncture-resistant, and has a strong seal strength making it an ideal choice for packaging irregular shaped products. It is made from 100% recyclable materials, has clarity, and a glossy self-appearance making it a great packing material for consumer products. POF is great for bundling multiple items together and can shrink completely and quickly. POF with perforations added to the wrap called pre-perforated shrink wrap allows air to escape during the shrinking process for attaining a smooth package.
Polyethylene (PE) is a type of polyolefin, used in several forms of flexible protective packaging. There are different forms of PE and the three most common are Low-Density Polyethylene (LDPE), Linear Low-Density Polyethylene (LLDPE), & High-Density Polyethylene (HDPE). The various forms are used in different industrial applications, but for shrink packaging, LDPE would be the best choice, as it has higher strength and more durability for heavier items. These shrink wraps can also have graphic images printed on them making it an ideal tool to enhance brand visibility and awareness. LDPE provides the greatest print quality. PE does not have a great shrink rate and has lower clarity as compared to other wraps.
While POF and PVC are limited in gauge thickness, higher gauges of PE are possible making it usable in marine industrial applications, like shrink wrapping a boat, huge machinery for storage. Shrink wrap packaging provides a way to create a tamper-resistant seal that will protect the product and keep it in good condition.