SIST EN IEC 61249-2-52:2026

SLOVENSKI STANDARD
01-januar-2026
Materiali za plošče tiskanih vezij in druge povezovalne strukture - 2-52. del:
Pokovinjeni in nepokovinjeni ojačeni osnovni materiali - Duromeri na osnovi
ogljikovodikov, laminati, ojačeni s tkanino iz e-stekla z definirano vnetljivostjo
(preskus navpične gorljivosti), bakrena obloga
Materials for printed boards and other interconnecting structures - Part 2-52: Reinforced
base materials clad and unclad - Thermosetting hydrocarbon resin system, woven e-
glass reinforced laminate sheets of defined flammability (vertical burning test), copper-
clad
Werkstoffe für Leiterplatten und andere Verbindungsstrukturen – Teil 2-52: Kaschierte
und unkaschierte verstärkte Basismaterialien – Duroplastisches
Kohlenwasserstoffharzsystem, E-Glasgewebe verstärkte Laminattafeln mit definierter
Brennbarkeit (Brennprüfung mit vertikaler Prüflingslage), kupferkaschiert
Matériaux pour circuits imprimés et autres structures d’interconnexion - Partie 2-52:
Matériaux de base renforcés, métallisés et non métallisés - Feuilles stratifiées renforcées
en tissu de verre de type e avec système de résines hydrocarbonées
thermodurcissables, d’inflammabilité définie (essai de combustion verticale), plaquées
cuivre
Ta slovenski standard je istoveten z: EN IEC 61249-2-52:2025
ICS:
31.180 Tiskana vezja (TIV) in tiskane Printed circuits and boards
plošče
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 61249-2-52

NORME EUROPÉENNE
EUROPÄISCHE NORM November 2025
ICS 31.180
English Version
Materials for printed boards and other interconnecting structures
- Part 2-52: Reinforced base materials clad and unclad -
Thermosetting hydrocarbon resin system, woven E-glass
reinforced laminate sheets of defined flammability (vertical
burning test), copper-clad
(IEC 61249-2-52:2025)
Matériaux pour circuits imprimés et autres structures Werkstoffe für Leiterplatten und andere
d'interconnexion - Partie 2-52: Matériaux de base renforcés, Verbindungsstrukturen - Teil 2-52: Kaschierte und
métallisés et non métallisés - Feuilles stratifiées renforcées unkaschierte verstärkte Basismaterialien - Duroplastisches
en tissu de verre de type E avec système de résines Kohlenwasserstoffharzsystem, E-Glasgewebe verstärkte
d'hydrocarbure thermodurcissables, d'inflammabilité définie Laminattafeln mit definierter Brennbarkeit (Brennprüfung mit
(essai de combustion verticale), plaquées cuivre vertikaler Prüflingslage), kupferkaschiert
(IEC 61249-2-52:2025) (IEC 61249-2-52:2025)
This European Standard was approved by CENELEC on 2025-10-21. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61249-2-52:2025 E

European foreword
The text of document 91/1977/CDV, future edition 1 of IEC 61249-2-52, prepared by TC 91
"Electronics assembly technology" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 61249-2-52:2025.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2026-10-31
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-10-31
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61249-2-52:2025 was approved by CENELEC as a
European Standard without any modification.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 61189-2 2006 Test methods for electrical materials, EN 61189-2 2006
printed boards and other interconnection
structures and assemblies - Part 2: Test
methods for materials for interconnection
structures
IEC 61249-5-1 - Materials for interconnection structures - EN 61249-5-1 -
Part 5: Sectional specification set for
conductive foils and films with and without
coatings - Section 1: Copper foils (for the
manufacture of copper-clad base
materials)
IEC 61249-6-3 - Materials for printed boards and other EN IEC 61249-6-3 -
interconnecting structures - Part 6-3:
Sectional specification set for
reinforcement materials - Specification for
finished fabric woven from ”E” glass for
printed boards
ISO 11014 2009 Safety data sheet for chemical products - - -
Content and order of sections
IEC 61249-2-52 ®
Edition 1.0 2025-09
INTERNATIONAL
STANDARD
Materials for printed boards and other interconnecting structures -
Part 2-52: Reinforced base materials clad and unclad - Thermosetting
hydrocarbon resin system, woven E-glass reinforced laminate sheets of defined
flammability (vertical burning test), copper-clad
ICS 31.180  ISBN 978-2-8327-0724-1

IEC 61249-2-52:2025-09(en)
IEC 61249-2-52:2025 © IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Materials and construction . 5
4.1 General . 5
4.2 Resin system . 5
4.3 Metal foil . 5
4.4 Reinforcement . 6
5 Internal marking . 6
6 Electrical properties . 6
7 Non-electrical properties of the copper-clad laminate . 7
7.1 Appearance of the copper-clad sheet . 7
7.1.1 General. 7
7.1.2 Indentations (pits and dents) . 7
7.1.3 Wrinkles . 7
7.1.4 Scratches . 7
7.1.5 Raised areas . 8
7.1.6 Surface waviness . 8
7.2 Appearance of the unclad face . 8
7.3 Laminate thickness . 8
7.4 Bow and twist . 8
7.5 Properties related to the copper foil bond . 9
7.6 Thermal stress . 10
7.7 Solderability . 10
7.8 Punching and machining . 10
7.9 Dimensional stability . 10
7.10 Sheet sizes . 11
7.10.1 Typical sheet sizes. 11
7.10.2 Tolerances for sheet sizes . 11
7.11 Cut panels . 11
7.11.1 Cut panel sizes . 11
7.11.2 Size tolerances for cut panels . 11
7.11.3 Rectangularity of cut panels . 11
8 Non-electrical properties of the base material after complete removal of the
copper foil . 12
8.1 Appearance of the dielectric base material . 12
8.2 Flexural strength . 12
8.3 Flammability. 13
8.4 Water absorption . 13
8.5 Measling . 14
8.6 Glass transition temperature and cure factor . 14
8.7 Decomposition temperature . 14
8.8 Time to delamination (TMA) . 14
8.9 Z-axis expansion . 14
8.10 X/Y-axis expansion . 15
IEC 61249-2-52:2025 © IEC 2025
8.11 Thermal conductivity . 15
9 Quality assurance . 15
9.1 Quality system. 15
9.2 Responsibility for inspection . 15
9.3 Qualification inspection . 15
9.3.1 General. 15
9.3.2 Sampling plan. 15
9.3.3 Frequency . 15
9.3.4 Judgment rules . 16
9.4 Quality conformance inspection . 17
9.4.1 General. 17
9.4.2 Inspection lot . 17
9.4.3 Test of Group A . 17
9.4.4 Test of Group B . 17
9.4.5 Test of Group C . 17
9.4.6 Judgment Rules . 17
9.4.7 Rejected lots . 17
9.5 Certificate of conformance . 17
9.6 Safety data sheet . 17
10 Packaging and marking . 18
11 Ordering information . 18
Annex A (informative) Common laminate constructions. 19
Bibliography . 20

Table 1 – Electrical properties . 6
Table 2 – Indentations . 7
Table 3 – Nominal thickness and tolerance of metal-clad laminate . 8
Table 4 – Bow and twist . 9
Table 5 – Peel strength . 9
Table 6 – Thermal stress . 10
Table 7 – Solderability . 10
Table 8 – Dimensional stability . 10
Table 9 – Size tolerance for cut panels . 11
Table 10 – Rectangularity of cut panels . 11
Table 11 – Flexural strength . 12
Table 12 – Flammability . 13
Table 13 – Water absorption . 13
Table 14 – Measling . 14
Table 15 – Decomposition temperature requirements . 14
Table 16 – Time to delamination requirements. 14
Table 17 – Z-axis expansion requirements . 14
Table 18 – X/Y-axis expansion requirements . 15
Table 19 – Qualification and conformance inspection . 16
Table A.1 – Thickness. 19

IEC 61249-2-52:2025 © IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Materials for printed boards and other interconnecting structures -
Part 2-52: Reinforced base materials clad and unclad - Thermosetting
hydrocarbon resin system, woven E-glass reinforced laminate sheets of
defined flammability (vertical burning test), copper-clad

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s) "). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
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services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC 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, IEC 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 https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 61249-2-52 has been prepared by IEC technical committee 91: Electronics assembly
technology. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
91/1977/CDV 91/2043/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
IEC 61249-2-52:2025 © IEC 2025
A list of all parts in the IEC 61249 series, published under the general title Materials for printed
boards and other interconnecting structures, can be found on the IEC website.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
IEC 61249-2-52:2025 © IEC 2025
1 Scope
This part of IEC 61249 gives requirements for properties of the thermosetting hydrocarbon resin
system, woven E-glass reinforced laminate sheets of defined flammability (vertical burning test),
copper-clad in thicknesses of 0,05 mm up to 3,20 mm.
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.
IEC 61189-2:2006, Test methods for electrical materials, printed boards and other
interconnection structures and assemblies - Part 2: Test methods for materials for
interconnection structures
IEC 61249-5-1, Materials for interconnection structures - Part 5: Sectional specification set for
conductive foils and films with and without coatings - Section 1: Copper foils (for the
manufacture of copper-clad base materials)
IEC 61249-6-3, Materials for printed boards and other interconnecting structures - Part 6-3:
Sectional specification set for reinforcement materials - Specification for finished fabric woven
from "E " glass for printed boards
ISO 11014:2009, Safety data sheet for chemical products - Content and order of sections
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
4 Materials and construction
4.1 General
...