The paper of the future will be thinner, smarter and made from new raw materials. But this does not imply the overthrow of traditional paper making methods. These innovations will be possible through the use of different fillers and fibres, such as aspen - the promising newcomer to the paper industry.

The forest industry corporation, M-real, is conducting strategic research on the suitability of the northern aspen for paper production. The traditional raw materials of paper are birch and pine. Aspen makes up only about 1.5 per cent of the volume of Finnish forests. Now, aspen plantations are being formed for the paper industry.

The excellence of aspen is based on the properties of its fibres. The walls of aspen wood fibres are thick and the particles on their surface diffuse light, with the result that paper made from aspen is non-transparent. Even on a very thin sheet of aspen paper, coloured pictures can be printed on both sides without them being seen on the other side.

Thinner paper is more economical for both the customer and the seller. Advertisers will get more printing surface per ton of paper than they do with traditional fine papers. The mill, on the other hand, will earn the same amount from groundwood-containing aspen paper, which is still classed as fine paper, than it does from traditional fine paper which may not contain groundwood.

Although aspen is in many respects a fine wood for paper production, the traditional northern species grows slowly. Yet, the hybrid aspen, a crossbreed of the Finnish and American aspens, has a three times faster growth rate. The wood material of the cloned aspen is also lighter, which is good for paper production.

Aspen research is important for silvicultural reasons, too. Especially the hybrid aspen faces many perils. The saplings need to be well taken care of for the forest to grow. The Metla forest research institute is running a project to investigate a series of aspen-related factors, such as the growth of different aspen species, the occurrence of fungal diseases and the destruction caused by animals.

>> www.metla.fi
>> www.m-real.com