Position letter: Release paper liner colour to enable recycling
One of the CELAB objectives is to increase the recycling rate of the paper release liner of the self-adhesive labels. CELAB-Europe has conducted a study with the European paper mills currently recycling the used liner to understand the impact of the liner colour on its recycling. The outcome of this study is that it is essential to have a good colour separation between the light and dark-coloured liner AND that light-coloured liners are preferred by the paper recycling mills. Therefore, CELAB strongly recommends all producers and users of paper release liners to only use – so that they are recyclable –white or lightly tinted release liners.
This position letter is based on a study done by CELAB-Europe on the recycling of the Self-adhesive Label release liner to evaluate the impact of the liner colour on its recycling. The conclusions are based on the feedback of paper liner recyclers identified by CELAB. Other industries are free to use the learning from CELAB to increase the recyclability and recycling rate of their material.
As this study focussed on recycling the paper liner back to fibre in a paper mill, only the perspectives of the recycling mills were taken into account in this position.
It is well-known that paper release liners require a specific treatment to be recycled in paper mills, to manage the special properties of siliconized glassine paper. As the paper mills involved in the study mostly produce white paper, they prefer to receive input waste material that is also white or only very lightly tinted.
It is common practice that recycling plants handling other wastepaper (like magazines, newsprint, cardboard, etc.) sort the white waste papers to make white papers again and use brown papers or other colours to make corrugated and cardboard papers. All possible deinking, bleaching, or other cleaning operations before recycling do not replace the need for the sorting step.
Most release liners for the majority of applications are either white or lightly tinted. Only some applications in specific market segments like the tape use dark coloured liners (mostly dark brown). In most cases, this dark colour is produced by adding certain chemical stains into the white pulp, as distinct to using brown unbleached pulp. It is estimated that the proportion of dark-stained liners is limited and represents only 10 to 20% of the total release liner applications. The stains used are incorporated into the paper fibers and cannot be removed by deinking. Also, in most known label applications, there appears to be no technical reason/need for the dark colouring. The most likely explanation for the use of stain to colour the liner is historical and/or for marketing reasons.
The factories recycling release liners into recycled paper cannot accept any dark coloured liners as input. Further, the relatively small proportion of brown liners does not justify the investment needed for sorting or other separation methods to remove the dark coloured liner. Even small amounts of dark coloured liners can spoil complete deliveries of used release liners and will lead to their incineration rather than recycling.
This study shows that it is essential to have a good colour separation between the light and dark-coloured liner AND that there is a clear preference from the paper recycling mills to receive only light-coloured liners to be used in their process efficiently.
Light blue is currently only accepted by a few recyclers and is considered less favourably to white and light-yellow liner waste.
The brown or any other dark stained paper liners are not favourably accepted by the paper release liner recyclers today and therefore are not recommended.
CELAB deals with all aspects of release liner recycling and CELAB therefore strongly recommends all producers and users of paper release liners to only use – so that they are recyclable – white or lightly tinted release liners.
|Type of colours||CELAB Positioning|
|White and light colours: lemon (light yellow), honey (beige)||Preferred: to be prioritised|
|Light blue||Acceptable in some cases, and in low quantities|
|Dark colours: brown, “havana”, “topaz”||Not recommended – consider switching to light colours|
For any questions on CELAB or this pledge please contact us directly at firstname.lastname@example.org or here.