Pressure-sensitive labels are self-adhesive labels that stick to containers when pressure is applied. It’s a widely used application for packaging, and even if you don’t use them yourself, you’ve most certainly come across them in your day-to-day life. Sure, there’s some advantages to using them, but there’s a lot of drawbacks. Read on to find out the truth about pressure-sensitive labels!
Adhesives and Vinyl in the Recycling Process
Pressure-sensitive labels (PSLs) that resist moisture are typically made from vinyl or polyvinyl chloride (PVC), both of which are single-use plastics. The thin plastic layer, along with the petroleum-based adhesives, complicates the recycling process and prevents these materials from breaking down in composting environments. According to Jonathan Wilker, a chemistry professor at Purdue University, “Almost all glues are petroleum-based and do not degrade. The bonded materials in our products stay stuck together. Consequently, we cannot recycle many of the materials that we put into our recycling bins. Discarded products will sit in landfills for centuries and, sometimes, contribute to ocean microplastics”.
https://www.purdue.edu/newsroom/releases/2023/Q3/solving-stickiness-sustainably.html
What can we learn from the materials used for moisture resistant pressure-sensitive labels? Vinyl labels are thin films of plastic with an adhesive applied which can be identified as single use plastics. When packaging any products we must provide labeling to the consumer, so they know what they are buying. Recent legislation to ban single-use plastics target some plastic labels but not all, moisture resistant labels are an important function of packaging using options that do not require adhesive is a step in the right direction when we are talking about the environment.
Application Challenges
If your production line involves high-speed automation labeling processes or you require large runs, PSLs are not a great choice.
- BUBBLING: While pressure-sensitive labels are easy to apply, improper application can result in bubbles or wrinkles that affect the overall appearance of the package.
- HEAT SENSITIVITY: Pressure-sensitive labels do not perform well in consistently high-temperature environments. The adhesive can melt, compromising the label.
- COST CONSIDERATIONS: Although cost-effective for short runs, pressure-sensitive labels can become less economical in large-scale production.
- ADHESIVE RESIDUE: Depending on the adhesive type, removing pressure-sensitive labels can leave a sticky residue making recycling more challenging.
- ALIGNMENT ISSUES: Labels occasionally end up off-center or skewed during application affecting aesthetics and functionality.
Additional Steps
Implementing PSL adds another step in the packaging process. Reducing steps can reclaim valuable time, often overlooked in cost calculations but crucial in the packaging workflow. Additional steps mean more labor, machinery, manufacturing space, and potential for errors, leading to more waste and the need for extra materials.
Sustainable Alternatives
Sustainable alternatives to pressure-sensitive labels are at think4D!
- In-Mold Labels (IML): Applied directly during the molding process, these labels become part of the container, simplifying recycling. IML offers versatile packaging options like tubs, tubes, and cups, allowing producers to use the same container for various labels.
- Shrink Sleeve Labels (SSL): These labels are easy to remove for recycling, keeping containers free from inks and enhancing recyclability. SSL materials that can be recycled in a single step make the process even easier for consumers. For more information, refer to our previous article on SSL.
- Printed Thermoforms: Often made from recyclable plastics, these can be easily disposed of in recycling bins, free from harmful adhesives.
Although IML, SSL, and printed thermoforms are single-use plastics, they are more straightforward to recycle compared to PSL. At think4D, we also have the latest in shrink sleeve sustainability…washable ink and a clear crystallizable PETG heat-shrink film! Read about them here.
When selecting packaging and labeling solutions for branding, consider all facts and options. Not all labels are created equally!