DIN EN ISO 8623:2011-02

This standard specifies the requirements and the corresponding test methods for distilled tall-oil fatty acids for paints and varnishes. ISO 8623:1997 is based on DIN 55961:1993-03, so that the requirements for tall-oil fatty acids and the determination of the content of free rosin acids are identical in both standards. The only exception is the requirement for the iodine value according to Wijs: with respect to the withdrawn standard DIN 55961:1993-03, the iodine value has been reduced from a minimum of 150 g iodine/100 g to a minimum of 125 g iodine/100 g. The standard is also harmonized with ASTM D 1984-69 (Reapproved 1992) "Standard Specification for Tall Oil Fatty Acids". The guide values given in DIN 55961:1993-03 for the fatty acid composition of the tall-oil fatty acids are not contained in ISO 8623:1997 and have therefore been adopted into national Annex NA (informative) of DIN EN ISO 8623. However, recording requirements has been avoided to for the content of certain fatty acids, as there is too little experience available concerning this subject. It is intended, for example, to limit the 9-,12-,15-linolenic acid content to less than 1 % in order to restrict the tendency to yellow. If this is considered to be necessary - for example, due to examination results - special arrangements may be made regarding this subject. In the formula for the calculation of the content of free rosin acids, the correction factor 1,042 for the unesterified fatty acids and the correction value 0,1 for slight esterification of rosin acids are in accordance with the Scandinavian regulation SCAN-T14:78. The Committee responsible for this standard is NA 002-00-02 AA "Lackrohstoffe" ("Raw materials for paints and varnishes") at DIN.