EN ISO 17232:2025

Leather - Physical and mechanical tests - Determination of heat resistance of patent leather (ISO 17232:2025)

This document specifies two methods for determining the heat resistance of patent leather.
Method A makes use of a modified lastometer, while Method B uses the “Zwik” apparatus. Both methods are applicable to patent leathers for all end uses.

Leder - Physikalische und mechanische Prüfungen - Bestimmung der Wärmebeständigkeit von Lackleder (ISO 17232:2025)

Cuir - Essais physiques et mécaniques - Détermination de la résistance à la chaleur des cuirs vernis (ISO 17232:2025)

Le présent document spécifie deux méthodes permettant de déterminer la résistance à la chaleur du cuir vernis.
La méthode A met en œuvre un lastomètre modifié, tandis que la méthode B utilise l’appareillage Zwik. Ces deux méthodes sont applicables aux cuirs vernis quelles que soient leurs utilisations finales.

Usnje - Fizikalni in mehanski preskusi - Ugotavljanje odpornosti lakastega usnja proti vročini (ISO/FDIS 17232:2025)

General Information

• Status: Published
• Publication Date: 16-Dec-2025
• ICS: 59.140.30 - Leather and furs
• Technical Committee: CEN/TC 289 - Leather
• Drafting Committee: CEN/TC 289/WG 2 - Physical test methods
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 17-Dec-2025
• Completion Date: 17-Dec-2025
• Ref Project: kSIST FprEN ISO 17232:2025 - Leather - Physical and mechanical tests - Determination of heat resistance of patent leather (ISO/FDIS 17232:2025)

Relations

• Replaces: EN ISO 17232:2017 - Leather - Physical and mechanical tests - Determination of heat resistance of patent leather (ISO 17232:2017)
• Effective Date: 09-Jul-2024

Overview

EN ISO 17232:2025 - Leather - Physical and mechanical tests - Determination of heat resistance of patent leather (ISO 17232:2025) is a CEN-adopted ISO draft that specifies two standardized methods to assess the heat resistance of patent (varnished) leather. Both methods are applicable to patent leathers for all end uses and are intended for routine quality control, product development and compliance testing.

Key topics and technical requirements

• Two test methods
  • Method A - Lastometer method
    • Uses a modified lastometer with a plunger terminating in a steel ball (Ø 21.0 ± 0.1 mm).
    • Test piece clamped to leave a central free circular area (Ø 25.0 ± 0.1 mm).
    • Specimen is distended by 7.5 mm ± 0.05 mm, heated and inspected.
    • Standard heating: 100 ± 5 °C for 180 ± 5 s; extended condition: 125 ± 5 °C for 300 ± 5 s.
  • Method B - Zwik method
    • Uses the “Zwik” apparatus with a half-cylinder mandrel (radius 15.0 ± 0.1 mm, length 25.5 ± 0.1 mm) and defined clamp geometry.
    • Test piece is stretched over the mandrel to a linear extension of 21 ± 1 %.
    • Six test pieces are prepared (three with long edge parallel to backbone, three perpendicular).
• Specimen preparation and conditioning
  • Selection and cutting of specimens in accordance with ISO 2418.
  • Conditioning per ISO 2419; tests are carried out shortly after conditioning.
• Apparatus & measurements
  • Hot air blower capable of required temperatures; temperature measurement to 1 °C; timing to 1 s.
  • Specific cutting and perforation tools (press knife, sewing needle specifications) described.
• Test reporting
  • Reports must reference ISO 17232:2025 and the method used, record damage before and after heating, state test temperature/time, conditioning atmosphere, specimen identification and any deviations.

Applications and users

• Who uses it
  • Leather manufacturers and finishers, footwear and fashion brands, upholstery and accessory producers, independent test laboratories, and conformity assessment bodies.
• Practical uses
  • Quality control of patent leather finishes to ensure resistance to heat-induced cracking, crazing or coating failure.
  • Supporting material selection for products exposed to elevated surface temperatures (e.g., footwear near heat sources, vehicle interiors, display samples).
  • Comparative testing during formulation or process changes to varnish systems and backing materials.

Related standards

• ISO 2418 - Specimen position and preparation
• ISO 2419 - Specimen conditioning (physical and mechanical tests)
• ISO 15115 / EN 15987 - Leather vocabulary and terminology

Keywords: ISO 17232:2025, patent leather heat resistance, lastometer, Zwik apparatus, leather testing, heat resistance test, CEN leather standards.

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 17232:2025
01-marec-2025
Usnje - Fizikalni in mehanski preskusi - Ugotavljanje odpornosti lakastega usnja
proti vročini (ISO/DIS 17232:2025)
Leather - Physical and mechanical tests - Determination of heat resistance of patent
leather (ISO/DIS 17232:2025)
Leder - Physikalische und mechanische Prüfungen - Bestimmung der
Wärmebeständigkeit von Lackleder (ISO/DIS 17232:2025)
Cuir - Essais physiques et mécaniques - Détermination de la résistance à la chaleur des
cuirs vernis (ISO/DIS 17232:2025)
Ta slovenski standard je istoveten z: prEN ISO 17232
ICS:
59.140.30 Usnje in krzno Leather and furs
oSIST prEN ISO 17232:2025 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 17232:2025
oSIST prEN ISO 17232:2025
DRAFT
International
Standard
ISO/DIS 17232
IUP 38
IULTCS
Leather — Physical and mechanical
Secretariat: ISO
tests — Determination of heat
resistance of patent leather
Voting begins on:
2025-01-07
Cuir — Essais physiques et mécaniques — Détermination de la
Voting terminates on:
résistance à la chaleur des cuirs vernis
2025-04-01
ICS: 59.140.30
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 17232:2025(en)
IUP 38:2025(en)
oSIST prEN ISO 17232:2025
ISO/DIS 17232:2025(en)
IUP 38:2025(en)
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
oSIST prEN ISO 17232:2025
ISO/DIS 17232:2025(en)
IUP 38:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Method A — Lastometer method . 1
4.1 Principle .1
4.2 Apparatus .1
4.3 Specimen and test piece preparation .2
4.4 Procedure .2
4.5 Test report .3
5 Method B — Zwik method . 3
5.1 Principle .3
5.2 Apparatus .3
5.3 Specimen and test piece preparation .5
5.4 Procedure .5
5.5 Test report .5
Annex A (informative) Sources of apparatus . 7

iii
oSIST prEN ISO 17232:2025
ISO/DIS 17232:2025(en)
IUP 38:2025(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 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).
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 or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of 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 www.iso.org/iso/foreword.html.
IULTCS, originally formed in 1897, is a world-wide organization of professional leather societies to further
the advancement of leather science and technology. IULTCS has three Commissions, which are responsible
for establishing international methods for the sampling and testing of leather. ISO recognizes IULTCS as an
international standardizing body for the preparation of test methods for leather.
ISO 17232 was prepared by the European Committee for Standardization (CEN) Technical Committee CEN/
TC 289, Leather, the secretariat of which is held by UNI, in collaboration with the Physical Test Commission
of the International Union of Leather Technologists and Chemists Societies (IUP Commission, IULTCS), in
accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
It is based on IUP 38 published in J. Soc. Leather Tech. Chem., 84 (7), p. 403, (2000), and declared an official
method of the IULTCS in March 2001.
This third edition cancels and replaces the second edition (ISO 17232:2017), which has been technically
revised with the following changes:
— align it with the changes and revised terminology in ISO 2418:2023 and ISO 2419:2024;
— modification of the testing conditions (4.3 and 5.3).
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
oSIST prEN ISO 17232:2025
ISO/DIS 17232:2025(en)
DRAFT International Standard
IUP 38:2025(en)
Leather — Physical and mechanical tests — Determination of
heat resistance of patent leather
1 Scope
This document specifies two methods for determining the heat resistance of patent leather.
Method A makes use of a modified lastometer, while Method B uses the “Zwik” apparatus. Both methods are
applicable to patent leathers for all end uses.
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 2418, Leather — Chemical, physical, mechanical and fastness tests — Position and preparation of specimens
for testing
ISO 2419, Leather — Physical and mechanical tests — Specimen and test piece conditioning
ISO 15115, Leather — Vocabulary
EN 15987, Leather — Terminology — Key definitions for the leather trade
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 15987 and ISO 15115 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Method A — Lastometer method
4.1 Principle
A perforated test piece is distended by a specified amount. The surface is heated and any damage to the
patent finish is noted.
4.2 Apparatus
4.2.1 Test machine, including the parts
...