A sustainable, recyclable alternative to waxed cardboard

Waterproof box coatings have traditionally been particularly unsustainable forms of packaging: firstly, the wax coatings are made from petrochemicals, and secondly, they render the cardboard not fit for recycling, sending 400,000 tonnes of wax-coated cardboard to landfill each year.

However, a new waterproofing coating that is both recyclable and renewable could soon be on the market.

Developed by the Queensland University of Technology’s (QUT’s) Albert Tietz and Adjunct Professor Les Edye, the lignin-based coating is being trialled on fruit boxes in the Northern Queensland banana-growing region. If all goes well, they expect the product will be on the market in mid-2015.

“We discovered the potential of lignin as a waterproof coating while researching ways to add value to bagasse in the sugar industry,” Professor Edye said.

“After some investigation and research, we’re now using lignin extracted from a commercially grown and processed grass.

“What’s most exciting is that our lignin barrier coating is sustainable - traditional wax coatings are made from petrochemicals and, once it’s on the paper or cardboard, that paper or cardboard can no longer be recycled.

“We’ve proven that our lignin coating is cost comparable, is 100% recyclable, provides a high level of waterproofing and strengthens the boxes to a higher degree than wax - not bad for a product made from a renewable resource.”

QUT’s innovation arm, qutbluebox, has provided more than $250,000 in proof-of-concept funding to develop and scale the coating for industry. The organisation has also secured a further $200,000 from Black Sheep Capital to optimise the coating’s formula and fund industrial-scale trials.

“We’ve already successfully coated the lignin-based formulation on food packaging and prefabricated honeycomb walls used in the construction industry. We’re now trialling it on fruit boxes for the banana industry,” said qutbluebox CEO Michael Finney.

“Both Australian and large-scale multinationals have expressed an interest in the coating’s development. Critically, the Black Sheep investment will help us fast-track the waterproof coating’s industrial-scale trialling.”