bleached kraft pulp paper from Canson® (Canson® barrier paper) made with a mix of hardwood and softwood fibres

Ingredients

bleached kraft pulp, hardwood fibres, softwood fibres, calcium carbonate

Preparation Steps

Original Recipe Text

The paper is a commercial bleached kraft pulp paper known as Canson barrier paper, produced with a mixture of hardwood and softwood fibres (Section 2.1). It is manufactured to comply with ISO 9706 standards, featuring an initial pH of 8.9 ± 0.2 and an alkaline reserve (AR) of 3.3 ± 0.3 % in calcium carbonate equivalent (Table 1). Its Kappa number is 2.6 (Table 1).

Evidence

"The permanent paper is a bleached kraft pulp paper from Canson® (Canson® barrier paper) made with a mix of hardwood and softwood fibres. Its pH, alkaline reserve (AR) and Kappa number comply with the ISO 9706 standard for paper permanency."

Remarks

This permanent paper demonstrates significantly slower degradation compared to acidic cotton paper. The cellulose scission rate in humid air is approximately 25 times lower than that of Whatman paper (Section 3.2). The research identifies a synergetic role of water and oxygen in the degradation process, noting that the paper is more sensitive to oxygen degradation than pure cotton cellulose (Abstract). Residual lignin, indicated by the Kappa index, contributes to stronger yellowing (b* coordinate) during ageing (Section 3.3.3). The study used closed Wheaton® glass tubes with multi-layered gas impermeable film to prevent leakage of volatile acid compounds during the 90°C accelerated ageing process (Section 2.2).