Shrink wrap packaging ensures to provide an appealing finished look for the product and also protects the product from dust, dirt, moisture and tampering. Shrink wrapping a product involves the right kind of plastic and proper heating conditions. During the packaging process, there can be certain issues that can occur due to which the final packaging can reflect certain defects. Some of the common shrink wrap problems you might experience are mentioned below.
- Dog Ears
This is one of the most common problems faced during the process of shrink packaging. When the shrink film becomes bunched up in sections of the packaging, this is called dog ears. This excess shrink wrap is a sign that there was insufficient shrinkage of the film. As they are triangular protrusions of the film on the corners of a package they resemble a dog’s ear. They can make it difficult for consumers to open the packages as they can be quite sharp to touch. Dog ears can be rectified by applying extra heat to remove or lessen the dog ears.
- Fish Eyes
Fish eyes are round or oval patterns that show up on film after the shrinking process. This is caused due to improper shrinkage of the shrink wrap. The presence of fish eyes on the packaging makes it look untidy and unbecoming. Fish eyes are normally caused due to a lack of heat and bad air velocity in the heating element of the shrink wrap machine. To avoid fish eyes, regular maintenance of the machine is required. Also slowing down the speed and allowing the heat to apply fully during shrink wrap packaging would minimise the occurrence of fish eyes.
The presence of excess air trapped inside the shrink wrap after it has been sealed causes balloon-type structures. Ballooning can create inadequacies in the protection of the product, and appear quite unappealing to the customer. It is one of the difficult shrink wrapping problems to tackle. The solution would be to switch to a pre-perforated film to help prevent ballooning. This type of film has tiny vent holes that allow air to escape after the film has been shrunk around the product. The other solution is to avoid exposing sealed packages to excess air.
- Burn Holes
Burn holes or hot spots happen when too much is heat is applied to the shrink wrap causing areas in shrink film to become hot and may cause unwanted holes in the shrink wrap film. Holes not only damage the durability of the packaging but can also cause damage to the product if the heat is too close. By adjusting the temperature, conveyor belt speed, and air velocity shrink film hot spots can be avoided.
Constant tearing of wrap during shrink wrap packaging and the splitting of seals around the product can result in damage to your product. The solution would be to switch to a thicker or different type of shrink film. Also cleaning of seal wire, checking the pressure applied by the clamp and setting of right temperature would help to solve these problems.