scope:

This part of ISO 4629 specifies a titrimetric method fordetermining the free hydroxyl groups in binders and bindersolutions for paints and varnishes. The hydroxyl groups may bepresent as polyhydric alcohols, partial esters, polyester endgroups or hydroxylated fatty acids. This method is not applicableto resins containing both hydroxyl groups and epoxy groups, becausethe latter will also be included in the result. Also the method isnot applicable to cellulose nitrate or to phenolic resins. NOTE 1If, in the case of binder solutions, the hydroxyl value of thebinder only is to be determined, the possibility that otherconstituents of the binder solution may contain hydroxyl groups hasto be taken into account. NOTE 2 A method for the determination ofthe hydroxyl value of epoxy resins is specified in ISO 7142