ISO 2135:2024

International
Standard
ISO 2135
Fifth edition
Anodizing of aluminium and its
2024-10
alloys — Accelerated test of light
fastness of coloured anodic oxidation
coatings using artificial light
Anodisation de l’aluminium et de ses alliages — Essai accéléré de
solidité à la lumière artificielle des couches anodiques colorées
Reference number
© ISO 2024
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ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 2
6 Test specimen . 2
6.1 Sampling .2
6.2 Size .2
6.3 Treatment before testing .2
7 Procedure . 3
7.1 Preparation of test specimen . .3
7.2 Exposure conditions .3
7.3 Period of exposure .3
7.3.1 For visual assessment .3
7.3.2 For instrumental assessment.4
8 Expression of results . 4
8.1 General .4
8.2 Visual assessment .4
8.3 Instrumental assessment .4
9 Test report . 4
Annex A (normative) Various light sources . 6
Bibliography . 7

iii
Foreword
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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
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This document was prepared by Technical Committee ISO/TC 79, Light metals and their alloys, Subcommittee
SC 2, Organic and anodic oxidation coatings on aluminium.
This fifth edition cancels and replaces the fourth edition (ISO 2135:2017), which has been technically
revised.
The main changes are as follows:
— the procedural description in Clause 4 has been moved to 7.3;
— the terms for representing European blue wool reference material have been unified into "blue wool
reference material";
— the term "light fastness number" has been specified in 3.1;
— the apparatus listed in the procedures have been added in Clause 5;
— the period of exposure for instrumental assessment has been specified.
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
International Standard ISO 2135:2024(en)
Anodizing of aluminium and its alloys — Accelerated test of
light fastness of coloured anodic oxidation coatings using
artificial light
1 Scope
This document specifies an accelerated test method for assessing the fastness, using artificial light, of
coloured anodic oxidation coatings on aluminium and its alloys.
For evaluating light fastness on exterior exposure, only outdoor exposure under conditions comparable with
actual service is completely satisfactory.
Accelerated testing is suitable as a quality-control test of coloured anodic oxidation coatings whose light
fastness number has already been established by means of outdoor exposure testing.
The method is applicable to coloured anodic oxidation coatings on aluminium and its alloys produced by any
means and for any purpose.
However, the method is not suitable for the measurement of coloured coatings with a light fastness number
already established by means of outdoor exposure testing and of less than 6.
The outdoor exposure test is described in ISO 105-B01.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 105-A02, Textiles — Tests for colour fastness — Part A02: Grey scale for assessing change in colour
ISO 105-B01, Textiles — Tests for colour fastness — Part B01: Colour fastness to light: Daylight
ISO 105-B02, Textiles — Tests for colour fastness — Part B02: Colour f
...