ISO 10716:2022

INTERNATIONAL ISO
STANDARD 10716
Second edition
2022-02
Paper and board — Determination of
alkali reserve
Papier et carton — Détermination de la réserve alcaline
Reference number
© ISO 2022
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 1
5.1 Hydrochloric acid . 2
5.2 Sodium hydroxide solution . 2
5.3 Methyl red . 2
6 Apparatus . 2
7 Sampling and preparation of test pieces . 2
8 Procedure .2
9 Calculation . 3
10 Precision . 3
11 Test report . 3
Annex A (informative) Precision . 4
iii
Foreword
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This document was prepared by Technical Committee ISO/TC 6, Paper, board and pulps.
This second edition cancels and replaces the first edition (ISO 10716:1994), of which it constitutes a
minor revision. The main changes are as follows.
— Clause 2 has been updated.
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iv
Introduction
Papers produced to be stable for long time periods normally contain some alkaline filler, such as calcium
carbonate, as an alkali reserve to prevent attack from acid substances in ambient air or formed by
deterioration of substances in the paper. Specifications for paper permanence can require a minimum
alkali reserve.
The required alkali reserve is obtained by adding some form of calcium carbonate to the paper furnish
but other substances can also be used for this purpose. By expressing the test results in moles per
kilogram of alkaline substances and not as a calcium carbonate content, no confusion arises when
alkaline substances other than calcium carbonate a
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