EN ISO 787-15:2019

SLOVENSKI STANDARD
01-december-2019
Nadomešča:
SIST EN ISO 787-15:1997
Splošne metode preskušanja pigmentov in polnil - 15. del: Primerjava svetlobne
obstojnosti barvnih pigmentov podobnih vrst (ISO 787-15:2019)
General methods of test for pigments and extenders - Part 15: Comparison of resistance
to light of coloured pigments of similar types (ISO 787-15:2019)
Allgemeine Prüfverfahren für Pigmente und Füllstoffe - Teil 15: Vergleich der
Beständigkeit bei Belichtung von Buntpigmenten ähnlichen Typs (ISO 787-15:2019)
Méthodes générales d'essai des pigments et matières de charge - Partie 15:
Comparaison de la résistance à la lumière des pigments colorés de types semblables
(ISO 787-15:2019)
Ta slovenski standard je istoveten z: EN ISO 787-15:2019
ICS:
87.060.10 Pigmenti in polnila Pigments and extenders
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 787-15
EUROPEAN STANDARD
NORME EUROPÉENNE
September 2019
EUROPÄISCHE NORM
ICS 87.060.10 Supersedes EN ISO 787-15:1995
English Version
General methods of test for pigments and extenders - Part
15: Comparison of resistance to light of coloured pigments
of similar types (ISO 787-15:2019)
Méthodes générales d'essai des pigments et matières Allgemeine Prüfverfahren für Pigmente und Füllstoffe -
de charge - Partie 15: Comparaison de la résistance à la Teil 15: Vergleich der Beständigkeit bei Belichtung von
lumière des pigments colorés de types semblables (ISO Buntpigmenten ähnlichen Typs (ISO 787-15:2019)
787-15:2019)
This European Standard was approved by CEN on 11 August 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 787-15:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 787-15:2019) has been prepared by Technical Committee ISO/TC 256
"Pigments, dyestuffs and extenders" in collaboration with Technical Committee CEN/TC 298 “Pigments
and extenders” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by March 2020, and conflicting national standards shall
be withdrawn at the latest by March 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 787-15:1995.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 787-15:2019 has been approved by CEN as EN ISO 787-15:2019 without any
modification.
INTERNATIONAL ISO
STANDARD 787-15
Second edition
2019-08
General methods of test for pigments
and extenders —
Part 15:
Comparison of resistance to light of
coloured pigments of similar types
Méthodes générales d'essai des pigments et matières de charge —
Partie 15: Comparaison de la résistance à la lumière des pigments
colorés de types semblables
Reference number
ISO 787-15:2019(E)
©
ISO 2019
ISO 787-15:2019(E)
© ISO 2019
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Published in Switzerland
ii © ISO 2019 – All rights reserved

ISO 787-15:2019(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus and materials. 2
6 Sampling . 4
7 Procedure. 5
7.1 Preparation of the test specimens . 5
7.2 Exposure of the test specimens . 5
8 Test report . 5
Bibliography . 7
ISO 787-15:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established 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.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 256, Pigments, dyestuffs and extenders.
This second edition cancels and replaces the first edition (ISO 787-15:1986), of which it constitutes a
minor revision. The changes compared to the previous edition are as follows:
— Clause 3 on “Terms and definitions”, with a general reference to ISO 18451-1, has been added;
— a bibliography has been added;
— the text has been editorially revised.
A list of all parts in the ISO 787 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved

ISO 787-15:2019(E)
Introduction
The terms “resistance to light” and “light fastness (or colour fastness)” describe the resistance of a
material to change in its appearance as a result of exposure to light. The magnitude of the change, if any,
is influenced by the quantity and quality of the light to which the material is exposed, and by the nature
and composition of the material itself. Two compositions, each consisting of identical components but in
different proportions, may not have the same resistance to light. Also, two compositions each consisting of
the same proportions of similar, but not identical, components may not have the same resistance to light.
When exposed to natural light, the conditions of the test vary continuously because of the large number
of variables (for example intensity and spectral distribution of the light, temperature, relative humidity,
and the amount and nature of atmospheric contaminants) and therefore results cannot be related to
similar tests carried out on other occasions. Consequently, expressing the results as a function of time
alone is not recommended.
These considerations form the basis for the comparison of light fastness of two different samples
of a coloured pigment. Each sample is incorporated in the same proportion in otherwise identical
compositions and these compositions, in a suitable form, are examined for any difference in their
change of appearance after exposure to the same quantity and quality of light. In order to comply with
these exposure conditions, it is necessary for the compositions to be exposed side by side at the same
time to the same light source for the same period of time.
In addition, the light fastness of a pigment may be affected by the presence of other pigments such as
titanium dioxide. This important aspect may be accommodated in document by allowing the agreed
binder (medium) to consist of a dispersion of such a pigment. The test procedure is then followed as
described.
The extent, to which the change on exposure is allowed to proceed before the comparison is made, may
be of importance. It is unrealistic to assess the exposures when the change is only equivalent to the
first perceptible change, but it is also inadvisable to wait until the amount of change is large. Thus, it is
recommended that comparisons of change of appearance be made when the amount of change of the
pigment with known resistance to light (agreed reference pigment) is equal to fastness grade 4 and 3 of
the grey scale in accordance with ISO 105-A02.
For any particular application, the method of test described in this document should be completed
by the following supplementary informati
...