IEC 61249-4-2:2005

Materials for printed boards and other interconnecting structures - Part 4-2: Sectional specification set for prepreg materials, unclad - Multifunctional epoxide woven E-glass prepreg of defined flammability

This part of IEC 61249 gives requirements for properties of prepreg that is mainly intended to be used as bonding sheets in connection with laminates according to IEC 61249-2-8 when manufacturing multilayer boards according to IEC 62326-4. This material may be also used to bond other types of laminates. Prepreg according to this standard is of defined flammability (vertical burning test). The flammability rating on fully cured prepreg is achieved through the use of brominated fire retardants contained as an integral part of the polymeric structure. After curing of the prepreg according to the supplier's instructions, the glass transition temperature is defined as 150 °C minimum.

General Information

• Status: Published
• Publication Date: 04-Sep-2005
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 31.180 - Printed circuits and boards
• Technical Committee: TC 91 - Electronics assembly technology
• Drafting Committee: WG 4 - TC 91/WG 4
• Current Stage: PPUB - Publication issued
• Start Date: 15-Dec-2005
• Completion Date: 05-Sep-2005

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 61249-4-2
First edition
2005-09
Materials for printed boards and
other interconnecting structures –
Part 4-2:
Sectional specification set for prepreg materials,
unclad – Multifunctional epoxide woven E-glass
prepreg of defined flammability
Reference number
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INTERNATIONAL IEC
STANDARD 61249-4-2
First edition
2005-09
Materials for printed boards and
other interconnecting structures –
Part 4-2:
Sectional specification set for prepreg materials,
unclad – Multifunctional epoxide woven E-glass
prepreg of defined flammability

 IEC 2005  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale M
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 61249-4-2  IEC:2005(E)
CONTENTS
FOREWORD.3

1 Scope.5
2 Normative references .5
3 Materials and construction.6
3.1 Reinforcement .6
3.2 Resin system.6
4 Properties.6
4.1 Properties related to the appearance of the prepreg .6
4.2 Properties related to B-stage prepreg .7
4.3 Properties related to prepreg after curing .8
5 Delivery form .9
5.1 Rolls.9
5.2 Sheets.10
5.3 Cut panels.10
6 Quality assurance.10
6.1 Quality system.10
6.2 Responsibility for inspection .10
6.3 Qualification inspection .10
6.4 Quality conformance inspection .10
6.5 Certificate of conformance.10
6.6 Safety data sheet .11
7 Packaging and marking .11
8 Shelf life .11
9 Ordering information.11

Table 1 – Flammability.9

61249-4-2  IEC:2005(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
MATERIALS FOR PRINTED BOARDS AND
OTHER INTERCONNECTING STRUCTURES –

Part 4-2: Sectional specification set for prepreg materials, unclad –
Multifunctional epoxide woven E-glass prepreg of defined flammability –

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
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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) 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.
International Standard IEC 61249-4-2 has been prepared by IEC technical committee 91:
Electronics assembly technology.
The text of this standard is based on the following documents:
FDIS Report on voting
91/526/FDIS 91/536/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – 61249-4-2  IEC:2005(E)
IEC 61249-4 consists of the following parts, under the general title Materials for printed
boards and other interconnecting structures – Part 4: Sectional specification set for prepreg
materials, unclad
Part 4-1: Epoxide woven E-glass prepreg of defined flammability
Part 4-2: Multifunctional epoxide woven E-glass prepreg of defined flammability
Part 4-5: Polyimide, modified or unmodified, woven E-glass prepreg of defined flammability
Part 4-11: Non-halogenated epoxide, woven E-glass prepreg of defined flammability
Part 4-12: Non-halogenated multifunctional epoxide woven E-glass prepreg of defined
flammability
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in the
data related to the specific publication. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

___________
Under consideration.
61249-4-2  IEC:2005(E) – 5 –
MATERIALS FOR PRINTED BOARDS AND
OTHER INTERCONNECTING STRUCTURES –

Part 4-2: Sectional specification set for prepreg materials, unclad –
Multifunctional epoxide woven E-glass prepreg of defined flammability

1 Scope
This part of IEC 61249 gives requirements for properties of prepreg that is mainly intended to
be used as bonding sheets in connection with laminates according to IEC 61249-2-8 when
manufacturing multilayer boards according to IEC 62326-4. This material may be also used to
bond other types of laminates.
Prepreg according to this standard is of defined flammability (vertical burning test). The
flammability rating on fully cured prepreg is achieved through the use of brominated fire
retardants contained as an integral part of the polymeric structure. After curing of the prepreg
according to the supplier’s instructions, the glass transition temperature is defined as 150 °C
minimum.
2 Normative references
The following referenced documents are indispensable for the application 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 61189-2:1997, Test methods for electrical materials, printed boards and other inter-
connecting structures and assemblies – Part 2: Test methods for materials for interconnection
structures
Amendment 1 (2000)
IEC 61249-2-8:2003, Materials for printed boards and other interconnecting structures – Part
2-8: Reinforced base materials, clad and unclad – Modified brominated epoxide woven
fibreglass reinforced laminated sheets of defined flammability, copper-clad
IEC 61249-6-3, Material for interconnection structures – Part 6-3: Sectional specification set
for reinforcement materials – Woven E-glass (for the manufacture of prepregs and copper-
clad base materials
IEC 62326-4:1996, Printed boards – Part 4: Rigid multilayer printed boards with interlayer
connections – Sectional specification
ISO 9000:2000, Quality management systems – Fundamentals and vocabulary
ISO 11014-1:1994, Safety data sheet for chemical products – Part 1: Content and order of
sections
ISO 14001:2004, Environmental management systems – Requirements with guidance for use

___________
In preparation.
– 6 – 61249-4-2  IEC:2005(E)
3 Materials and construction
The prepreg consists of a reinforcing E-glass fabric which is impregnated with epoxide resin
and partially cured to the B-stage.
3.1 Reinforcement
Woven E-glass as specified in IEC 61249-6-3: Woven E-glass fabric (for the manufacture of
prepreg and copper-clad laminate).
3.2 Resin system
The resin consists of a majoriity multifunctional epoxide resin with an E-glass transition
temperature of ≥150 °C when cured according the manufacturer’s recommendation.
Contrast agents may be added to enhance processing such as automated optical inspection.
Its flame resistance is defined in terms of the flammability requirements of 4.3.2.
4 Properties
4.1 Properties related to the appearance of the prepreg
The prepreg shall be substantially free from defects that may have an impact on the material’s
fitness for use for the intended
...