Paper, pulp and board ageing

Paper, pulp and board ageing

How are printed matters, documents and packaging affected by age? Heat, cold, light and moisture influence characteristics such as strength, look and archivability, but how much and is it critical? MoRe can find out!

Ageing, or weathering as it is also called, seldom happens quickly and must therefore be tested with methods which in a reasonable amount of time can predict the consequences of ageing under different conditions. Different factors also often interact which affects ageing of various pulp, paper and board products. We can test and expose samples to different conditions and in a relatively short period of time get the results.

One type of products we test is not allowed to yellow with age, e.g. printed matters, documents and packaging when these have to maintain their appearance for a long time. By measuring the optical characteristics of the sample before, during and after the ageing test in our Suntest we can see whether the material is up to the customer’s demands. The test is done as an accelerated ageing. The ageing can be monitored with optical measurements during the test period. By exposing a reference product to the same ageing we get an answer how well the tested product is doing compared to the reference.

Not only UV light from the sun and other light sources is critical for how quickly the ageing takes place and its consequences. The questions from our customers are even more complex. Weathering tests can be done as part of product development of new papers or boards, e.g. if you want to know which are the consequences of different pulp mixtures or coating.

Cold also influences ageing and a customer might be interested in knowing how packaging is affected by long-term storage at a low temperature. We can also test how strength characteristics change, i.e. deteriorate, under the influence of heat and moisture. For that kind of investigation we measure different critical strength characteristics before, during and after ageing and can thus answer if the product meets the demands in question.

A reference is always good when we do our tests, but we can also reliably determine ageing according to different standards, such as for archival paper. We can also issue certificates certifying a papers archivability.

Contact: Pia Renström +46 70 381 56 57 E-mail