The waste reduction agency conducted trails on removable coloured coatings, shrink sleeves and self-peel labels to see whether the techniques are up to the task of replacing conventional in-mould labels and pressure sensitive labels.
Increasing recycling rates
The theory behind the investigation was that by removing colour from rigid plastic packaging, the range of end markets for recycled material would increase making the recovery of mixed plastics more attractive to recycling businesses. The ultimate goal is to increase recycling levels.
The WRAP investigation looked at both the commercial feasibility of the colour techniques and their impact on the environment.
Overall the conclusion was that the technologies were viable and presented a potentially important means of increasing recycling rates. Even if, in some cases, the immediate environmental impact would be slightly negative, higher recycling levels would outweigh any such effects.
Techniques compared
Looking at the techniques individually, removable ink was shown to be a promising novel means of adding colour but needs further development work to make it commercially viable.
WRAP said it sent samples of trays and photographs with mock-up samples filled with mushrooms to UK retailers and had a positive response but more work is needed to test the effectiveness of removable inks.
As for shrink labels, the investigation found that they were readily available and could easily replace in-mould labels. But there were some financial constraints related to the slightly higher cost of shrink sleeves and the capital investment needed to make the switch.
And finally use of self-peeling labels for certain types of container was found to give immediate recycling benefits.
Comparing the options WRAP said: “Currently while there are minor technical issues associated with the full roll out of the removable ink technology that can be resolved by further detailed research, there are financial considerations limiting but not preventing the adoption of the sleeve and label technologies.
The adoption of these technologies to a wider range of packaging could be encouraged with flagship products and campaigns by industry or packaging organisations, brand owners, retailers and packaging business promoting these recycling friendly forms of colouration and decoration.”