ISO 3135

ISO/PRF 3135:2025(en)
ISO /TC 10/WG 18
Secretariat: SIS
Date: 2025-01-2402-25
Marking pens — Durability of written line — Documentary use
(DOC)
PROOF
ISO/DISPRF 3135:2024(E2025(en)
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Published in Switzerland
ii © ISO 2024 2025 – All rights reserved
ii
ISO/PRF 3135:2025(en)
Contents
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 2
5 Test equipment and accessories . 2
6 Testing . 3
7 Marking . 4
8 Test report . 4
Bibliography . 6

Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 1
4.1 Water resistance . 1
4.2 Ethanol resistance . 1
4.3 Hydrochloric acid resistance . 1
4.4 Ammonium hydroxide resistance . 2
4.5 Bleaching resistance . 2
4.6 Erasure resistance. 2
4.7 Light resistance . 2
4.8 Reproducibility . 2
5 Test equipment and accessories . 2
5.1 Performance testing paper . 2
5.2 Eraser . 2
5.3 Light test apparatus . 2
5.4 Reproducibility apparatus . 2
5.5 Test solutions . 2
5.5.1 Ethanol solution . 2
5.5.2 Hydrochloric acid solution . 2
5.5.3 Ammonium hydroxide solution . 2
5.5.4 Bleaching solution . 2
6 Testing . 2
6.1 Sampling . 2
6.2 Climatic conditions for testing . 2
6.3 Procedure . 3
6.3.1 Preparation of test piece . 3
6.3.2 Water resistance test . 3
6.3.3 Ethanol resistance test . 3
© ISO 2025 – All rights reserved
iii
ISO/DISPRF 3135:2024(E2025(en)
6.3.4 Hydrochloric acid resistance test . 3
6.3.5 Ammonium hydroxide resistance test . 3
6.3.6 Bleaching resistance test . 3
6.3.7 Erasure resistance test . 3
6.3.8 Light resistance test . 3
6.3.9 Reproducibility test . 3
7 Marking . 4
8 Test report . 4
Bibliography . 5

iv © ISO 2024 2025 – All rights reserved
iv
ISO/PRF 3135:2025(en)
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity
...