EN ISO 4045:1998

SLOVENSKI STANDARD
01-februar-2000
8VQMH'RþHYDQMHS+,62
Leather - Determination of pH (ISO 4045:1977)
Leder - Bestimmung des pH (ISO 4045:1977)
Cuir - Détermination du pH (ISO 4045:1977)
Ta slovenski standard je istoveten z: EN ISO 4045:1998
ICS:
59.140.30
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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INTERNATIONAL STANDARD
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION l MEXflYHAPOAHAR OPI-AHM3ALJMII IIO CrAHAAPTM3ALW-i *ORGANISATION INTERNATIONALE DE NORMALISATION
Determination of pH
Leather -
Cuir - D&ermination du p H
First edition - 1977-09-15
Ref. No. ISO 4045-1977 (E)
UDC 675 : 543.257.1
Descriptors : leather, Chemical tests, measurement, pH.
Price based on 2 pages
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
International organizations,
up has the right to be represented on that committee.
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 4045 was developed by Technical Committee
ISO/TC 120, Leather, and was circulated to the member bodies in May 1976.
lt has been approved by the member bodies of the following countries :
Austral ia Hungary
Netherlands
Brazil I ndia New Zealand
Canada Iran Poland
Chile I reland
Portugal
Czechoslovakia Israel South Africa, Rep. of
France Korea, Rep. of
Spain
Germany Mexico Turkey
f the following
The member body o country expressed disapproval of the docu ment
on technical grounds
U.S.S.R.
0 International Organization for Standardization, 1977 l
Printed in Switzerland
ISO 4045-1977 (E)
INTERNATIONAL STANDARD
Leather - Determination of pl-l
5.2 Buffer Solution, for calibrating the electrode System.
1 SCOPE AND FIELD OF APPLICATION
lt is preferable to purchase a Standard buffer Solution for
This International Standard specifies a method for
measurement. If purchased in concentrated form, the
determining the pH and the differente figure of an aqueous
control buffer must be freshly prepared each time. The
leather extract.
length of time for which buffer solutions will keep
depends on their composition and the method of use.
2 REFERENCES
Control of the accuracy of the buffer Solution is therefore
indispensable.
ISO 4044, Leather - Preparation of Chemical test
samples.
Used buffer Solution shall be discarded.
ISO. . ., Leather - Methods o f sampling for Chemical
analysis. IJ
3 DEFINITION
6 APPARATUS
of this International Standard the
For the purpose
6.1 Suitable shaker, adjusted to a frequency of
following definition applies :
50 kl0 min-l.
differente figure : The differente between the pH value of
a Solution and that of its ten-fold dilution.
6.2 pH meter with glass electrode, with a measuring range
lt is a measure of the strength of acids and bases and tan
from 0 to 14 pH units, graduated in 0,05 pH unit. The
never exceed the value 1. The differente figure amounts to
electrode System shall be calibrated at intervals against the
0,7 to 1,O when a Solution contains a free strong acid (or a
buffer Solution (5.2).
free strong base). The ionization of weak acids and bases
NOTE
- Aqueous ext
...