Sustainable substrates can be bio-based, recycled or biodegradable. Natural-based substrates include cotton, bamboo, and trees and wood.
After a first general overview of the various possibilities of bio-based materials in sustainable hygiene products, we will take a closer look at different sustainable substrates. Such substrates can be used for all kinds of hygienic products, such as baby nappies, femcare or incontinence products.
There is a broad range of different natural substrates:
- Cotton
- Viscose/Bamboo
- Tissue/Cellulose
- Bio-PE (Sugar Cane; Corn)
- PLA (Corn; Starch)
If you want to produce sustainable hygiene products using sustainable substrates, it is important to know that the more diverse the substrates being used, the more demanding the requirements on the bonding mechanism.
To ensure the best quality and product performance in addition to improving sustainability, you should involve your adhesive supplier when redesigning the hygiene product.
Consumers have a strong positive impression of natural materials like cotton and bamboo and are attracted by their promise at the point of sale. Natural-based substrates are often considered to be purer and more skin friendly, alongside having benefits for sustainability.
Cotton is characterised by high softness and good absorption — one part of cotton can absorb up to 24 parts of water. That's why it's optimal for use in sustainable hygiene products.
At the same time, cotton is breathable, compostable/biodegradable under aerobic conditions, and originates from a renewable source.
Bamboo fibre is a cellulose fibre extracted from the bamboo plant. It is characterised by high absorption, while being soft and flexible. Bamboo is not only a very fast-growing raw material (3–4 months), it also absorbs twice as much CO2 from the air as trees and at the same time produces 30% more oxygen. After use, bamboo fibre naturally degrades. In personal hygiene products it used mainly for the production of core fluff and in the non-woven fabric.
Made from the fibres of wood and cotton, tissue/cellulose films are sometimes used for wrapping the core of nappies. Additionally, wood pulp is the major sustainable material used in hygiene products for core absorption.
These are just three possibilities for replacing existing components in hygiene products with natural substrates. Due to the special properties of natural substrates, the choice of the right adhesive for production is fundamental.
Bio-based plastics are made from corn or sugar cane and normally have a significantly lower carbon footprint than fossil-based plastics, but in many cases offer the same properties in terms of transparency, gloss and stiffness. Bio-based plastics can be—but are not necessarily—biodegradable or compostable and are used, for example, in the backsheets of nappies.
Bio-based polylactic acid (PLA) is one of the most important biodegradable and bio-based thermoplastics and is derived from renewable resources such as corn starch, tapioca or sugar cane via the fermentation of starch (dextrose). PLA spunlace & spunbond non-woven are used in the topsheet, backsheet and core. PLA offers sustainable benefits such as a low carbon footprint, renewable sourcing and industrial compostability.
With the right hot melt adhesive, the most demanding bonding tasks can easily be fulfilled thanks to the adhesives' excellent flexibility.