[(Superseding IS 6213 (Part 7) : 1971]

NATIONAL FOREWORD

This Indian Standard (Part 4/Sec 2) which is identical with ISO 1762 : 2015 ‘Paper, board and pulps — Determination of residue (ash) on ignition at 525°C’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Paper and Its Products Sectional Committee and approval of the Chemical Division Council.

For obtaining good quality of paper, it is essential that the pulp, which goes into the manufacture of paper, is properly cooked and bleached. This standard will guide the pulp and paper mills for the methods to be adopted for analysis of pulp.

The standard, IS 6213 (Part 7) was first published in 1971, wherein the ignition temperature was prescribed as 575 ± 25°C and was intended for testing of pulps only. This standard, based on ISO 1762, is for paper, board and pulps, wherein the ignition temperature has been prescribed as 525 ± 25°C. Considering the fact that it is required to follow uniform practices globally, it was felt appropriate to adopt ISO 1762. This standard supersedes IS 6213 (Part 7) : 1971 ‘Methods of test for pulps: Part 7 Ash content in pulp’.

While adopting ISO Standards on different test methods, it is observed that there are three broad based titles given by ISO, namely, ‘Paper, board and pulps’, ‘Paper and board’ and ‘Pulps’ under which most of the test methods are published. The three already published Indian Standards, namely, IS 1060 (Parts 1, 2 and 3) ‘Methods of sampling and test for paper and allied products’ are widely used and known to all concerned. In addition, there is IS 6213 series of standards published for ‘Methods of test for pulps’. Therefore, in order to maintain continuity and help to find the relevant test methods easily, all the adopted standards on test methods are being published under the following titles:

IS 1060 Methods of sampling and test for paper and allied products:

(Part 4) Methods of test for paper, board and pulps

(Part 5) Methods of test for paper and board

(Part 6) Methods of test for paper

(Part 7) Methods of test for board

IS 6213 series for Methods of test for pulp

The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions are however not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’.

b) Comma (,) has been used as a decimal marker while in Indian Standards, the current practice is to use a point (.) as the decimal marker.