2131 NTERNATIONAL STANDARD TSO INTERNATIONAL ORGANIZATION FOR STANDARDIZATION -MEKIYHAPOJHAH OPrAHW3AIM HIO CTAHIAPTH3AIHW.ORGANISATION INTERNATIONALE DE NORMALISATION Surface active agents -- Simplified classification First edition - 1972-11-01 NOV 1 1912 ISO 2131-1972 (E) UDC 661.185 : 168.2 Ref. No. ISO 2131-1972 (E) Descriptors : surfactants, classifying Price based on 5 pages Copyright International Organization for Standardization nitted without license from IHS Not for Resale FOREWORD Iso (the International Organization for Standardization) is a worldwide federation of national standards institutes (ISO Member Bodies). The work of developing International Standards is carried out through isO Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that Committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. Draft International Standards adopted by the Technical Committees are circulated to the Member Bodies for approval before their acceptance as International Standards by the ISO Council. International Standard IsO 2131 was drawn up by Technical Committee ISO/Tc 91, Surface active agents. It was approved in June 1971 by the Member Bodies of the following countries : Japan Australia Spain Austria Korea, Rep. of Switzerland Belgium New Zealand Thailand Egypt, Arab Rep. of Turkey Poland United Kingdom France Portugal Germany Romania U.S.A. South Africa, Rep. of Israel U.S.S.R. No Member Body expressed disapproval of the document. @ International Organization for Standardization, 1972 Printed in Switzerland Copyright International Organization for Standardization Not for Resale INTERNATIONAL STANDARD ISO 2131-1972 (E) Surface active agents -- Simplified classification 1 SCOPE AND FIELD OF APPLICATION Rule 2 This International Standard establishes simplified In the presence of several hydrophilic groups with classification of surface active agents, in conformity, identical ionic characters, select as the principal regarding the arrangement of radicals, with the scientific hydrophilic group that which is designated first in the classification (ISO/R 896). following numbering order, with reference to the divisions in the Table in the Annex : 2 PRINCIPLE for groups which are The simplified classification of surface active agents enables their characteristics to be expressed by an abbreviated anionic : 2 - 3 - 4 - 5 - 6 - 7 8 - 9 - 1 lettering and numbering system, consisting of a letter and cationic : 5- 6 - 7 - 8 -- 9 - 1 - 2 - 3 -- 4 four figures (five in the case of compounds comprising several hydrophilic groups), for the main structural ele- non-ionic : 3- 4- 5 6 - 1-2-- 7- 8 - 9 ments of the molecule, using Rule 3 1) the letter to designate the ionic character; in the presence of several hydrophilic groups with 2) the 1st figure to designate the hydrophilic group; different ionic characters, two alternatives must be considered : 3) the 2nd figure to designate the hydrophobic group; a) in the presence of anionic and cationic groups 4) the 3rd figure to designate an intermediate (ampholytic compounds), use the letter Z. Designate functional group; the cationic group first and the anionic group second, 5) the 4th figure to designate a supplementary property in parentheses, applying Rule 2 if necessary; of the hydrophilic group; b) in the presence of an ionic group and a non-ionic 6) the 5th figure (in parentheses between the 1st and group, use as the letter that which characterises the 2nd) to designate the second hydrophilic group of ionic group. Designate this first and the non-ionic compounds comprising several hydrophilic groups of group second, in parentheses, applying Rule 2 if necessary. different ionic characters. The operation is carried out by determining, from the classification Table given in the Annex arising from the general scientific classificatio