Rosin in paper and paperboard

This method describes empirical procedures for the quantitative determination of rosin in paper and paperboard.

Total extractable resin includes rosin added as a sizing agent, natural resins from the pulp, fatty acids and esters added as sizing and defoaming agents, and other natural and synthetic resins.

The quantitative procedures aimed at determining rosin in the presence of volatile or non-volatile neutral extractives will include as rosin any fatty acid present in the alcohol extract.

Qualitative tests, indicating the presence or absence of rosin added as a sizing agent, will be found in Section 12; Qualitative tests.

This method is not suitable for the quantitative determination of fatty acids and fatty salts in paper due to partial esterification during extraction.

This method is not applicable to the determination of wet strength resins.

It has been found that melamine formaldehyde resin does not interfere with the rosin determination (1).