The company has already completed extensive development work to commercialise the new technology.

The foam forming process involves aerating the water-fibre suspension with a stream of tiny bubbles, to make the paperboard structure bulkier but lighter in weight.

In addition, fibres are distributed more evenly in the web, which improves formation of the board and results in more consistent properties and appearance. The technology also reduces the use of raw materials, energy and water, which enhances sustainability, according to Metsä.

“We have already seen that the technology works in a laboratory environment as well as on pilot machines,” said chief executive Mika Joukio.

“Following promising laboratory scale results and our detailed feasibility studies, we reached a decision to invest in further development of the technology on a production machine.

“Our target is to offer our customers even more efficient and ecologically sound paperboards in the future.”

Metsä Board is a forerunner in developing the foam forming technology. The company has been carrying out research in association with VTT Technical Research Centre of Finland under the Finnish Bioeconomy Cluster FIBIC's research programmes.

Machine supplier Valmet is installing the technology at Metsä Board’s Kyro mill.

The company’s paperboard is mainly used for the packaging of cosmetics and healthcare products, foods, cigarettes, and consumer durables as well as graphics.

The company, which is headquarted in Finland, has approximately 3,100 employees and its sales totalled €2bn (£1.42bn) in 2014. It is part of Metsä Group, which has approximately 10,500 employees across 30 countries, with sales totalling €5bn (£3.56bn) in 2014.