IEC 61249-4-2:2005

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
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International Electrotechnical Commission
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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
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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
...