Paper testing
Our main interest is paper which is to be used in document preparation. In addition, we have been engaged in research and development projects, in order to find relevant methods for evaluation of paper permanence by e.g. accelerated ageing methods.
Permanent paper (ISO 9706)
- shall have a pH-value between 7,5 and 10,0
- shall have an alkali reserve at least corresponding to 0,4 mol acid per kg paper (at least 2% calcium carbonate)
- shall have tearing resistance of at least 350 mN
- shall have a Kappa number less than 5, which means that the paper may contain only a small amount of easily oxidized material (e.g. lignin)
Archival paper (ISO 11108)
- shall be made from cotton, cotton linters, hemp or flax, but may contain a minor fraction of fully bleached chemical pulp
- shall have a folding endurance of at least 2,18 (MIT-, Köhler Molin- or Lhomargy-instrument) or 2,42 (Schopper instrument)
Archival paper shall meet the requirements for permanent paper. The archival papers is stronger than the permanent paper and can withstand considerably more handling.
Permanence
Permanent documents are those that may be kept for several hundred of years in protected enviroments. Either paper or archival paper is recommended.
Certification of paper
Archival papers and permanent papers are tested in accordance with the Swedish National Archives Technical Regulation RA-FS 2006:4 which refers to ISO 11108 (archival paper) and ISO 9706 (permanent paper). Paper may be certified in accordance with the Swedish National Archives Regulations. SP is the only Swedish accredited certification body, see link to the right "Certification of archival materials".