EN IEC 61249-6-3:2023

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

This International Standard covers finished fabrics woven from ‘‘E’’ glass electrical grade glass fibre yarns that are intended as a reinforcing material in laminated plastics for electrical and electronic use. All fabrics covered by this specification are plain weave. This specification determines the nomenclature, definitions, general and chemical requirements for the glass, and physical requirements for finished woven glass fibre fabrics. Annex A of this standard provides a style designator for each finished fabric glass style, with specifications on yarn, fabric count, thickness and weight in both SI and US system.

Materialien für Leiterplatten und andere Verbindungsstrukturen - Teil 6-3: Rahmenspezifikationen für Verstärkungsmaterialien - Spezifikation für mit Haftvermittler ausgerüstete Gewebe aus E-Glasfaser-Garnen für Leiterplatten

Matériaux pour circuits imprimés et autres structures d’interconnexion - Partie 6-3 : Ensemble de spécifications intermédiaires pour matériaux de renfort - Spécification des tissus finis en verre "E" pour circuits imprimés

L'IEC 61249-6-3:2023 couvre les tissus finis fabriqués à partir de fils de fibre de verre de qualité électrique (verre "E"), qui sont destinés à servir de matériau de renfort dans les plastiques stratifiés à usage électrique et électronique. Tous les tissus couverts par cette spécification sont en armure toile. Cette spécification détermine la nomenclature, les définitions, les exigences générales et chimiques relatives au verre, ainsi que les exigences physiques des tissus finis en fibre de verre. L’Annex A du présent document fournit un identifiant pour chaque modèle de verre pour tissu fini, ainsi que les spécifications de fil, de contexture de tissu, d’épaisseur et de poids dans les deux systèmes de mesure, le Système international (SI) et les unités de mesure américaines (système US). Cette première édition annule et remplace l’IEC/PAS 61249-6-3 parue en 2011. Cette édition constitue une révision technique.

Materiali za plošče tiskanih vezij in druge povezovalne strukture - 6-3. del: Nabor oddelčnih specifikacij za armaturne materiale - Specifikacija za apretirane tkanine, tkane s steklenimi vlakni "E" za tiskana vezja

Ta mednarodni standard zajema apretirane tkanine, tkane s prejo iz steklenih vlaken električnega razreda »E«, ki so predvidene kot armaturni material v izdelkih iz laminirane plastike za električno in elektronsko uporabo. Vse tkanine, zajete v tej specifikaciji, so tkane s platno vezavo.
Ta specifikacija določa nomenklaturo, definicije, splošne in kemijske zahteve za steklo ter fizične zahteve za apretirane tkanine, tkane s steklenimi vlakni.
V dodatku A tega standarda so podane oznake za posamezne vrste apretiranih steklenih tkanin ter specifikacije v zvezi s prejo, številom vlaken, debelino in težo tako v mednarodnem sistemu enot (SI) kot ameriškem sistemu enot (US).

General Information

• Status: Published
• Publication Date: 03-Aug-2023
• Withdrawal Date: 03-Jan-2023
• ICS: 31.180 - Printed circuits and boards
• Technical Committee: CLC/SR 91 - Electronics assembly technology
• Drafting Committee: IEC/TC 91 - IEC_TC_91
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 04-Aug-2023
• Completion Date: 04-Aug-2023
• Ref Project: SIST EN IEC 61249-6-3:2024 - 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

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2024
Materiali za plošče tiskanih vezij in druge povezovalne strukture - 6-3. del: Nabor
oddelčnih specifikacij za armaturne materiale - Specifikacija za apretirane tkanine,
tkane s steklenimi vlakni "E" za tiskana vezja
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
Materialien für Leiterplatten und andere Verbindungsstrukturen – Teil 6-3:
Rahmenspezifikationen für Verstärkungsmaterialien – Spezifikation für mit Haftvermittler
ausgerüstete Gewebe aus E-Glasfaser-Garnen für Leiterplatten
Matériaux pour circuits imprimés et autres structures d’interconnexion - Partie 6-3 :
Ensemble de spécifications intermédiaires pour matériaux de renfort - Spécification des
tissus finis en verre "E" pour circuits imprimés
Ta slovenski standard je istoveten z: EN IEC 61249-6-3:2023
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 61249-6-3

NORME EUROPÉENNE
EUROPÄISCHE NORM August 2023
ICS 31.180
English Version
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
(IEC 61249-6-3:2023)
Matériaux pour circuits imprimés et autres structures Materialien für Leiterplatten und andere
d'interconnexion - Partie 6-3 : Ensemble de spécifications Verbindungsstrukturen - Teil 6-3: Rahmenspezifikationen
intermédiaires pour matériaux de renfort - Spécification des für Verstärkungsmaterialien - Spezifikation für mit
tissus finis en verre "E" pour circuits imprimés Haftvermittler ausgerüstete Gewebe aus E-Glasfaser-
(IEC 61249-6-3:2023) Garnen für Leiterplatten
(IEC 61249-6-3:2023)
This European Standard was approved by CENELEC on 2023-07-19. 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
© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61249-6-3:2023 E

European foreword
The text of document 91/1680/CDV, future edition 1 of IEC 61249-6-3, prepared by IEC/TC 91
"Electronics assembly technology" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 61249-6-3:2023.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2024-04-19
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2026-07-19
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 61249-6-3:2023 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 61189-2:2006 NOTE Approved as EN 61189-2:2006 (not modified)
ISO 2078 NOTE Approved as EN ISO 2078
ISO 3344 NOTE Approved as EN ISO 3344
ISO 9001 NOTE Approved as EN ISO 9001

IEC 61249-6-3 ®
Edition 1.0 2023-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
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

Matériaux pour circuits imprimés et autres structures d’interconnexion –

Partie 6-3: Ensemble de spécifications intermédiaires pour matériaux de renfort

– Spécification des tissus finis en verre "E" pour circuits imprimés

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.180 ISBN 978-2-8322-7070-7

– 2 – IEC 61249-6-3:2023 © IEC 2023
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Visual requirements . 9
5 Physical requirements . 10
5.1 Fabric count . 10
5.2 Weave type . 10
5.3 Fabric thickness . 10
5.4 Fabric weight . 10
5.5 Fabric length . 10
5.6 Fabric width . 10
5.7 Feather length . 10
5.8 Filament diameter . 10
5.9 Bare glass nominal measurement . 11
6 Chemical requirements . 11
7 Electrical requirements . 11
7.1 Dielectric constant . 11
7.2 Dissipation factor . 11
8 Workmanship requirements . 12
8.1 Splices . 12
8.2 Laser machinability performance . 12
8.3 Alternate fabric styles and weaves . 12
9 Quality assurance . 12
9.1 Statistical process control (SPC) . 12
9.2 Responsibility for inspection . 13
9.3 Test equipment and inspection facilities . 13
9.4 Preparation of samples . 13
9.5 Standard laboratory conditions . 13
9.6 Inspection requirements and acceptability . 13
9.6.1 General . 13
9.6.2 Sample size . 13
9.6.3 Sampling plans . 14
9.6.4 Acceptable quality level (AQL) . 14
9.7 Test methods . 14
9.7.1 Fabric appearance . 14
9.7.2 Fabric count . 15
9.7.3 Weave type . 15
9.7.4 Fabric thickness . 15
9.7.5 Weight per unit area . 15
9.7.6 Fabric length . 16
9.7.7 Fabric width . 16
9.7.8 Finish level (organic content) . 16
9.7.9 Bias or bowed filling . 17
10 Preparation for delivery . 17
10.1 Preservation and packaging . 17

IEC 61249-6-3:2023 © IEC 2023 – 3 –
10.2 Packing . 17
10.3 Marking . 17
11 Additional Information . 17
11.1 Ordering data . 17
11.2 New styles . 17
Annex A (normative) Finished fabric glass styles in SI units . 18
Bibliography . 21

Table 1 – Classification of defects . 9
Table 2 – Filament Thdiameter designations . 10
Table 3 – Bare glass nominal measurements . 11
Table 4 – Sample size per number of rolls shipped . 13
Table 5 – Sample size per length of individual roll shipped and

the acceptable quality level . 14

– 4 – IEC 61249-6-3:2023 © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
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

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
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
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
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 61249-6-3 has been prepared by IEC technical committee 91: Electronics assembly
technology. It is an International Standard.
This first edition cancels and replaces the IEC/PAS 61249-6-3 published in 2011. This edition
constitutes a technical revision.
The text of this International Standard is based on the following documents:
Draft Report on voting
91/1680/CDV 91/1828A/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 61249-6-3:2023 © IEC 2023 – 5 –
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/standardsdev/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,
• replaced by a revised edition, or
• amended.
– 6 – IEC 61249-6-3:2023 © IEC 2023
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

1 Scope
This part of IEC 61249 covers finished fabrics woven from ‘‘E’’ glass electrical grade glass fibre
yarns that are intended as a reinforcing material in laminated plastics for electrical and
electronic use. All fabrics covered by this specification are plain weave.
This specification determines the nomenclature, definitions, general and chemical requirements
for the glass, and physical requirements for finished woven glass fibre fabrics.
Annex A of this document provides a style designator for each finished fabric glass style, with
specifications on yarn, fabric count, thickness and weight in both SI and US system.
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.
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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
3.1
AQL
Acceptable Quality Level
maximum number of defects per hundred units that can be considered satisfactory as a process
average
3.2
bias
filling yarns are off-square to the warp ends
3.3
bow
filling yarns lie in an arc across the width of the fabric

IEC 61249-6-3:2023 © IEC 2023 – 7 –
3.4
creases
ridge in the fabric caused by a fold or wrinkle being placed under pressure
3.5
defect
substandard area in a fabric
3.5.1
major defect
defect that is likely to result in failure, or to reduce materially the usability of the unit of product
for its intended purpose
3.5.2
minor defect
defect that is not likely to reduce materially the usability of the unit of product for its intended
purpose
3.6
E-glass
Electrical Glass which is to be used for printed board applications, is a continuous filament
glass yarn with a chemical composition by weight that is within the following limits:

B2O3 5 % to 10 %
CaO 16 % to 25 %
Al2O3 12 % to 16 %
SiO2 52 % to 56 %
MgO 0 % to 5 %
Na2O / K2O 0 % to 2 %
TiO2 0 % to 0,8 %
Fe2O3 0,05 % to 0,4 %
F2 0 % to 10 %
Note 1 to entry: For convenience, the composition of borosilicate glass is often expressed in terms of oxides (B2O3,
SiO2, Al2O3, Na2O, CaO, etc.). This does not imply anything about the nature and structure of glass. Borates are
network formers and are part of the structure of borosilicate glass. All raw materials are completely consumed during
manufacturing, and no raw materials are present in the final product.
3.7
permittivity for bulk form E glass
reference dielectric constant to be used for printed board applications
3.8
feather length
distance from last warp end to the end of the pick
3.9
fabric finish
treatment of fabric to aid in compatibility with resins
3.10
fish eye
small area of fabric which resists resin wetting and can be caused by the resin system, fabric
or treatment
– 8 – IEC 61249-6-3:2023 © IEC 2023
3.11
hollow filament
individual filament within a glass yarn bundle that contains a longitudinal void
3.12
Leno end out
missing wrapper warp end from the edge of the fabric
3.13
lot
collection of units produced in one continuous, uninterrupted finish run from which a sample is
drawn and inspected or tested to determine conformance with the acceptability criteria.
3.14
mark
heavy or light area in fabric due to excessive or less filling yarns
3.14.1
heavy mark
filling defect extending across the width of the fabric containing two picks/inch in excess of the
nominal count
3.14.2
light mark
filling defect extending across the width of the fabric containing two picks/inch less than the
nominal count
3.15
pick
filling yarn running crosswise the entire width of a fabric
3.16
broken pick
filling yarn missing from a portion of the width of the fabric
3.17
mis-picks
break in the pattern of cloth from selvage to selvage caused by a missing filling yarn
3.18
plain weave
fabric configuration where each warp end should go over one pick and under the next, and each
pick should go over one warp end and under the next
3.19
split
opening in the fabric resulting from either the pick or end breaking in two
3.20
spread glass fabric
woven glass fabric, the warp and/or fill yarns of which, through mechanical action, are flattened
(spread out) such that the radial cross sectional aspect ratio (ratio of length of major and minor
axes) is increased and the percentage of open space between yarns per unit area is decreased,
as compared to a non-spread fabric of the same style

IEC 61249-6-3:2023 © IEC 2023 – 9 –
3.21
TEX system
system for expressing linear density of yarn or other textile strand expressed as
grams/kilometer
3.22
waste
lump or collection of yarn or filament woven into the fabric where accumulated contamination
off the loom has found its way into the fabric
3.23
waviness
cloth is woven under varying tensions preventing even placement of picks resulting in
alternating thick and thin places
4 Visual requirements
When specified by purchase contract, the fabric is examined in accordance with 9.7.1. Visual
defects shall be identified and classified per Table 1 and meet the AQL defined in 9.6.3 and
9.6.4 as specified.
Table 1 – Classification of defects
Visual Defect Description Classification
Pick line distortion from horizontal by more than 2,5 %
a
Bias or bowed filling Major
for entire width
Baggy or wavy cloth Clearly noticeable per 9.7.1 Major
Cut or tear > 6,5 mm in any direction (body only) Major
Spots, streaks, stains, foreign
Clearly noticeable Major
inclusions
Broken or missing ends or
2 or more continuous, regardless of length Major
picks
Light marks > 6,5 mm in width Major
2 picks/2,54 cm less than nominal Minor
Heavy marks Puckering clearly noticeable Major
2 picks/2,54 cm more than nominal Minor
Crease Hard embedded and folded over on self Major
Waste Clearly noticeable > 6,5 mm Major
Clearly noticeable ≤ 6,5 mm Minor
Weave separation Clearly noticeable >3,175 mm Major
Leno ends out >5 m Major
≤5 m Minor
Feather length >5 mm running >4,5 m Major
>5 mm running ≤4,5 m Minor
a
It is important that as a target for the future, the non-homogeneous bow (i
...