Sustainability in its simplest terms means, giving back to Mother-Earth or environment, society, or economy, whatever you draw from it. It ultimately delivers a message for us to leave a safer planet with minimum or no depletion of resources, for generations that follow, after meeting your own imperative needs. Let us for example consider just paper. Long years ago, with development of paper, there was a lot of promotions to increase its usage, but then it was realized that paper production was hugely dependent on wood and increased usage meant deforestation.
It is an accepted fact that forests are very important for a healthy environment and climate. It was on this realization that a lot of emphasis started to be put on avoiding unnecessary paper usage. Even now responsible company emails have a footnote advising not to print unless absolutely necessary. On the other hand, there are statutory directives to paper mills to aid afforestation so as to increase the forest cover and replenish the amount of wood extracted. However still, usage of paper is sustainable when produced with implementation of replenishing the inputs used. Moreover, the paper waste is re-pulpable to again produce paper or paper board aiding circular economy. Production of all manufactured goods and services should avoid or reduce using resources that cannot be replaced and whose depletion will adversely impact the environment. As mentioned above, paper is mostly produced from wood whose extended use in paper production leads to deforestation. For this reason, a lot of manufacturers do a life cycle analysis of products to achieve a level of sustainability.
Brand owners and large label user companies have now started insisting on FSC certified paper usage. Forest Stewardship Council (FSC) is a globally recognized certification system that ensures that the forests are managed sustainably. Products that are manufactured from responsibly harvested forests are identified with the FSC logo, which is considered the “gold standard” of forest certification by major environmental groups.
Circular economy also referred to as circularity and CE, refers to a type of process for production and consumption, which conforms to reusing, repairing, refurbishing or recycling materials and products. Since CE helps in reducing raw material requirement, carbon footprint and aids sustainability, it has gained popularity. It also helps in conservation of important resources. For an example of CE, milk pouches are made of mono polymers like LDPE for packaging which is easily recycled or reprocessed to again convert to plastic granules that can be remolded into usable plastic products. On the flip side, multi-polymer multi-layered film pouches are not recyclable and end up in landfills impacting environment adversely as they also do not biodegrade.
However, there is work being done to develop processes that will enable these also to be recycled. The government of India is actively formulating policies and promoting projects that will drive the country towards a circular economy system. It is estimated that a circular economy path adopted by India could bring in annual benefits of 40 lakh crores or approximately US$ 624 billion in 2050.
The material for labelstock consists of many elements and sustainability cannot be in the total laminate, each component must be sustainable and contribute. The self-adhesive label laminate primarily consists of face stock with or without a primer or lamination, pressure sensitive adhesive and siliconized release paper or film. To be sustainable each element must be dwelled upon separately. The life cycle of each of these is different and an analysis needs to be done in-depth to make decisions towards achieving sustainability goals.
Climate change and environmental concerns have now become issues that cannot be ignored and need to be attended to, at national and global levels. With increased statutory government directives to reduce carbon footprint and make sustainability an imperative, manufacturers are under pressure to re-engineer their products and their packaging. Leading brands have committed themselves to sustainability and circular economy to reduce their carbon footprint. Labels also being a part of packaging must be designed to achieve maximum level of sustainability and circular economy. FMCG brand owners are now preferring packaging solutions that will enable them to achieve decrease in their carbon footprint ensuring recycling of packaging material which is environment friendly. It is thus necessary to dwell on the different components of self-adhesive labels and their diverse usage. In India Avery Dennison has launched a matrix and liner recycling program to aid these needs. The liner collected from converters is sent to a company who repulps the liner mixed with wastepaper to produce tissue for shoe industry or other paper board items. The matrix is converted to briquettes and used as fuel.
The label face material is the actual performing part of the label that after application stays with the product during its entire lifecycle. Variety of substrates are used to be the label depending on its performance and aesthetics. These can be papers that are either coated or uncoated, plastic films or other materials. Even paper labels laminated with films are in use. Unlaminated paper is, as such, largely re-pulpable and converted to become recycled paper or paperboard to be reused but here we need to understand that in case of self-adhesive labels, paper alone does not get affixed to the product, it has an adhesive with it. The final label with the adhesive goes on to the product while the waste matrix after die-cutting in converting is waste that often goes to landfills impacting the environment adversely. It can also be shredded and molded as pellets or bricks to be used as fuel.
To that extent we can consider the waste matrix sustainable as it is put to constructive use. However still, the label that is affixed on the product has to be disposed along with the adhesive and the package it is on. So, we need to use special adhesives for the label to be re-pulpable in case of use on paper based packaging, or removable or washed off for recycling, when applied on reusable glass containers. We dwell on adhesives later in this article. Going backwards label buyers also have started insisting for their vendors to use FSC certified papers. FSC® or Forest Stewardship Council® certified paper is paper that has been harvested in a responsible manner. FSC stands for sustainable sourcing that puts forests and people first.
In case of filmic labels besides adhesive, it is another issue with worldwide movement against use of plastics wherever avoidable. The reason for this is that plastics are largely not biodegradable or non-compostable, so they are not ecofriendly. With EPR becoming mandatory in India, companies are constantly trying to use materials that can be recycled or reused. According to EPR or Extended Producers Responsibility, which is the responsibility of Producers, Importers and Brand-owners to ensure processing of their plastic packaging waste through recycling, re-use or end of life disposal (such as co-processing/Waste-to-energy/Plastic to-oil/roadmaking/industrial-composting).
The impact is evident from the fact that most companies are shifting towards paper based packaging or even paper based self-adhesive tapes. Many filmic labels are based on mono polymer PE, PP or PET so if they are used on bottles made with same polymer these can be recycled provided the adhesive is compatible. Some companies have been making changes in manufacturing to improve the recyclability of product packaging and look at ways of reducing carbon footprint. New films, made with 30-50% post-consumer recycled material or made with biobased materials, are offered that aid the circular economy and reduce the use of fossil based packaging while reducing carbon footprint. Some of these films available are fully compostable. Specially designed thinner films that are converted to be used for highspeed labeling are being preferred as using less material, is a good step toward sustainability.
Often when assessing the sustainability of a packaging, people tend to overlook the impact of adhesives that are an inherent part of the package. An adhesive that may hinder the recyclability or maybe non compostable will become a setback for the efforts to make labels and stickers sustainable. An adhesive must be chosen, such that it will comply with end-of-life process to recycle and reuse or be compostable.
With advancements in technology, adhesives are derived from either natural or synthetic raw materials. A general perception, that adhesives formulated with natural inputs may be sustainable and those made from synthetics are not sustainable, is not true as a rule. Both types of adhesives can be developed and formulated to perform and yet conform to sustainability. It is important to study and select adhesive for labels based on your need. Let us for example consider self-adhesive beer labels in returnable glass bottles. In this case the adhesive should be compostable and easily washable to separate from the glass bottle for the bottle to be washed and reused while the label in the water can also be separated, recycled or dispose without adversely impacting environment. In case of PE bottles with PE labels, the adhesive should be compatible, such that it can be shredded granulated along with the bottle for remolding. For each application the selection of adhesive is important.
Over fifty percent of self-adhesive labelstock used for manufacturing labels or stickers is generated as waste in converting. This is a known and accepted fact. The waste, more often than not, goes to landfills impacting environment. The release liner that protects the adhesive until the label is dispensed and applied, forms a major part of the waste generated. Since many years companies have been looking at options to either do away with the liner or reducing the waste generated by the liner.
Paper based liners form more than 80% release liners used for self-adhesive labels. The paper-based liners include Glassine, SCK, CCK and Poly coated papers. Linerless labels have been considered and used for some years now but due to growing need for better aesthetics, die-cutting complex shapes and embellishments, they have limited use. To reduce the tonnage of liner waste going to landfills as a sustainability endeavor, there has been talk of reducing the caliper/grammage of liner used but not much headway has been made in this direction.
In India and Europe, glassine is largely used as the preferred release liner and accounts to over 70% of all paper liners used. For long, release papers were not considered recyclable due to the silicone coating which after crosslinking becomes inert. However with development in technology, some companies in Europe and USA developed a de-siliconization process after which the paper can be processed to reproduce base papers for siliconizing. In the process, siliconized liner is repulped in water containing chemicals to release the silicone and remove the small silicone particles like in the process used for deinking of repulped printed papers. The de-siliconized pulp can then be used to produce new products, such as fine and specialty papers like release liner, label face, writing and printing papers. Thereby achieving circularity.
There has been substantial growth in use of filmic liners that are thinner and can take more labels per roll. The residual filmic liner can be recycled, enabling circularity. To achieve an elevated level of circular economy and sustainability, “CELAB” (Circular Economy for Labels), was set up by 50 industry-leading companies representing the entire value chain that have come together to create a sustainable pressure sensitive labeling industry by offering solutions and providing education to enable matrix and liner recycling.
It is an ad-hoc coalition empowered to reach across the entire supply chain and leverage the expertise of industry participants to promote a circular economy for self-adhesive label materials. CELAB’s members comprise industry members both large and small, and with both global and regional market presence. It also includes companies up and down the value chain of the matrix and liner industry. According to CELAB, “Like many other grades of film, silicone coated filmic release liners are recycled by regrinding the film into chips/pellets which can then be mixed with ‘virgin’ polymer and re-introduced to a film extrusion line for production of new polymeric film.”
Self-adhesive or pressure sensitive labels industry was at one time considered to be generating waste that was polluting the environment but gradually all-around efforts are driving in sustainability and recyclability. It is a matter of time the processes will evolve and the industry will shed the waste generating tag and grow.
Written by Harveer Sahni, Chairman Weldon Celloplast Limited New Delhi-India January 2023