IEC 61249-2-38:2008

IEC 61249-2-38
Edition 1.0 2008-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Materials for printed boards and other interconnecting structures –
Part 2-38: Reinforced base materials, clad and unclad – Non-halogenated
epoxide woven E-glass laminate sheets of defined flammability (vertical burning
test), copper-clad for lead-free assembly

Matériaux pour circuits imprimés et autres structures d'interconnexion –
Partie 2-38: Matériaux de base renforcés, plaqués et non plaqués – Feuilles
stratifiées en tissu de verre de type E époxyde non halogénées, plaquées cuivre,
d’inflammabilité définie (essai de combustion verticale) pour les assemblages
sans plomb
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IEC 61249-2-38
Edition 1.0 2008-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Materials for printed boards and other interconnecting structures –
Part 2-38: Reinforced base materials, clad and unclad – Non-halogenated
epoxide woven E-glass laminate sheets of defined flammability (vertical burning
test), copper-clad for lead-free assembly

Matériaux pour circuits imprimés et autres structures d'interconnexion –
Partie 2-38: Matériaux de base renforcés, plaqués et non plaqués – Feuilles
stratifiées en tissu de verre de type E époxyde non halogénées, plaquées
cuivre, d’inflammabilité définie (essai de combustion verticale) pour les
assemblages sans plomb
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
S
CODE PRIX
ICS 31.180 ISBN 978-2-88910-460-4
– 2 – 61249-2-38 © IEC:2008
CONTENTS
FOREWORD.4
1 Scope.6
2 Normative references.6
3 Materials and construction .6
3.1 Resin system.6
3.2 Metal foil .7
3.3 Reinforcement .7
4 Internal marking.7
5 Electrical properties .7
6 Non-electrical properties of the copper-clad laminate .8
6.1 Appearance of the copper-clad sheet .8
6.1.1 Indentations (pits and dents) .8
6.1.2 Wrinkles .8
6.1.3 Scratches .8
6.1.4 Raised areas .8
6.1.5 Surface waviness.9
6.2 Appearance of the unclad face.9
6.3 Laminate thickness.9
6.4 Bow and twist .9
6.5 Properties related to the copper foil bond.10
6.6 Punching and machining.11
6.7 Dimensional stability.11
6.8 Sheet sizes.12
6.8.1 Typical sheet sizes .12
6.8.2 Tolerances for sheet sizes .12
6.9 Cut panels .12
6.9.1 Cut panel sizes .12
6.9.2 Size tolerances for cut panels .12
6.9.3 Rectangularity of cut panels .13
7 Non-electrical properties of the base material after complete removal of the copper
foil.13
7.1 Appearance of the dielectric base material.13
7.2 Flexural strength.13
7.3 Flammability .14
7.4 Water absorption .14
7.5 Measling.15
7.6 Glass transition temperature and cure factor.15
7.7 Decomposition temperature .15
7.8 Thermal resistance .16
7.9 Z-axis expansion .16
8 Quality assurance .16
8.1 Quality system .16
8.2 Responsibility for inspection.16
8.3 Qualification inspection.16
8.4 Quality conformance inspection .16
8.5 Certificate of conformance.17

61249-2-38 © IEC:2008 – 3 –
8.6 Safety data sheet.17
9 Packaging and marking.17
10 Ordering information .17
Annex A (informative) Engineering information .18
Annex B (informative) Common laminate constructions.20
Annex C (informative) Guideline for qualification and conformance inspection.22
Bibliography .23

Table 1 – Electrical properties .7
Table 2 – Nominal thickness and tolerance of metal-clad laminate.9
Table 3 – Bow and twist .10
Table 4 – Pull-off and peel strength .11
Table 5 – Dimensional stability .12
Table 6 – Size tolerance for cut panels .12
Table 7 – Rectangularity of cut panels .13
Table 8 – Flexural strength.14
Table 9 – Flammability .14
Table 10 – Water absorption .14
Table 11 – Measling.15
Table 12 – Glass transition temperature and cure factor .15
Table 13 – Decomposition temperature .15
Table 14 – Thermal resistance .16
Table 15 – Z-axis expansion.16

– 4 – 61249-2-38 © IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MATERIALS FOR PRINTED BOARDS
AND OTHER INTERCONNECTING STRUCTURES –

Part 2-38: Reinforced base materials, clad and unclad –
Non-halogenated epoxide woven E-glass laminate sheets
of defined flammability (vertical burning test),
copper-clad for lead-free assembly

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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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.
International Standard IEC 61249-2-38 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
91/812/FDIS 91/834/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.

61249-2-38 © IEC:2008 – 5 –
A list of all parts of the IEC 61249 series, under the general title Materials for printed boards
and other interconnecting structures, can be found on the IEC website.
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.
– 6 – 61249-2-38 © IEC:2008
MATERIALS FOR PRINTED BOARDS
AND OTHER INTERCONNECTING STRUCTURES –

Part 2-38: Reinforced base materials, clad and unclad –
Non-halogenated epoxide woven E-glass laminate sheets
of defined flammability (vertical burning test),
copper-clad for lead-free assembly

1 Scope
This part of IEC 61249 gives requirements for properties of di-functional non-halogenated
epoxide woven E-glass laminate sheet 0,05 mm up to 3,2 mm, of defined flammability (vertical
burning test), copper-clad. The glass transition temperature is defined to be 120 °C minimum.
Its flame resistance is defined in terms of the flammability requirements of 7.3.
Some property requirements may have several classes of performance. The class desired
should be specified on the purchase order otherwise the default class of material will be
supplied.
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 61189-2:2006, Test methods for electrical materials, printed boards and other
interconnection structures and assemblies – Part 2: Test method for interconnection structures
IEC 61249-5-1:1995, 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)
ISO 9000, Quality management systems – Fundamentals and vocabulary
ISO 11014-1, Safety data sheet for chemical products – Part 1: Content and order of sections
ISO 14001, Environmental management systems – Requirements with guidance for use
3 Materials and construction
The sheet consists of an insulating base with metal-foil bonded to one side or both.
3.1 Resin system
Majority di-functional non-halogenated epoxide, modified non-halogenated epoxide, woven E-
glass laminate with a glass transition temperature of 120 °C minimum. The flammability rating
is achieved through the use of non-halogenated flame retardants reacted into the polymer.
Inorganic fillers may be used. Contrast agents may be added to enhance processing such as
automated optical inspection (AOI).

61249-2-38 © IEC:2008 – 7 –
-
The maximum total halogens contained in the resin plus reinforcement matrix is 1 500 × 10
6 -6 -6
with a maximum chlorine of 900 × 10 and maximum bromine being 900 × 10 .
Its flame resistance is defined in terms of the flammability requirements of 7.3.
3.2 Metal foil
Copper as specified in IEC 61249-5-1, copper foil (for the manufacture of copper-clad
materials). The preferred foils are electro-deposited of defined ductility.
3.3 Reinforcement
Woven E-glass as specified in the future IEC 61249-6-3, Woven E-glass fabric (for the
manufacture of prepreg and copper clad materials).
4 Internal marking
Not specified.
5 Electrical properties
The electrical property requirements are shown in Table 1.
Table 1 – Electrical properties
Test method
Property Requirements
(IEC 61189-2)
Resistance of foil 2E12 As specified in IEC 61249-5-1
Surface resistance after damp heat
while in the humidity chamber 2E03 ≥10 000 MΩ
(optional)
Surface resistance after damp heat
2E03
≥50 000 MΩ
and recovery
Volume resistivity after damp heat
while in the humidity chamber 2E04 ≥5 000 MΩm
(optional)
Volume resistivity after damp heat and
2E04 ≥10 000 MΩm
recovery
Relative permittivity after damp heat
2E10
≤5,4
and recovery (1 MHz)
Dissipation factor after damp heat and
2E10
≤0,035
recovery (1 MHz)
Electric strength (only for material
2E11 ≥30 kV/mm
thickness less than 0,5 mm)
Arc resistance 2E14
≥60 s
Dielectric breakdown (only for material
2E15 ≥40 kV
thicknesses ≥0,5mm)
Surface resistance at 125 °C 2E07 ≥1 000 MΩ
2E07
Volume resistivity at 125 °C ≥1 000 MΩm

– 8 – 61249-2-38 © IEC:2008
6 Non-electrical properties of the copper-clad laminate
6.1 Appearance of the copper-clad sheet
The copper-clad face shall be substantially free from defects that may have an impact on the
material´s fitness for use for the intended purpose.
For the following specific defects the requirements given shall apply when inspection is made
in accordance with IEC 61189-2 method 2M18.
6.1.1 Indentations (pits and dents)
The size of an indentation, usually the length, shall be determined and given a point value to be
used as measure of the quality.
Point value for each
Size
mm indentation
0,13 – 0,25 1
0,26 – 0,50 2
0,51 – 0,75 4
0,76 – 1,00 7
Over 1,00 30
The total point count for any 300 mm × 300 mm area shall be calculated to determine the class
of the material.
Class A 29 maximum
Class B 17 maximum
Class C 5 maximum
Class D 0
Class X To be agreed upon by user and supplier
The required class of material shall be specified in the purchase order. Class A applies unless
otherwise specified.
6.1.2 Wrinkles
There shall be no wrinkles in the copper surface.
6.1.3 Scratches
Scratches deeper than 20 % of the nominal thickness of the foil thickness are not permitted.
Scratches with a depth less than 5 % of the nominal thickness of the foil shall not be counted
unless this depth is 10 μm or more.
Scratches with a depth between 5 % and 20 % of the nominal thickness of the foil are
permitted to a total length of 100 mm for a 300 mm × 300 mm area.
6.1.4 Raised areas
Raised areas are usually impressions in the press plates used during manufacture but may
also be caused by blisters or inclusions of foreign particles under the foil.
Raised areas caused by blisters or inclusions are not permitted.

61249-2-38 © IEC:2008 – 9 –
Raised areas being impressions of defects in press plates are permitted to the following extent:
Class A and X material maximum height 15 μm and maximum length 15 mm;
Class B and C material maximum height 8 μm and maximum length 15 mm;
Class D material maximum height 5 μm and maximum length 15 mm.
6.1.5 Surface waviness
When examined in accordance with test method 2M12 of IEC 61189-2, the surface waviness in
both the machine and cross machine direction shall not exceed 7 μm.
6.2 Appearance of the unclad face
The unclad face of single side clad sheet shall have the natural appearance resulting from the
curing process. Small irregularities in colour are permitted. The gloss of the unclad face shall
be that given by the press plate or release foil used. Variations of gloss due to the impact of
pressure of gases released during the curing are permitted.
6.3 Laminate thickness
The laminate thickness may be ordered to include or exclude the copper foil contribution as
specified in the purchase order. As a general rule, laminates less than 0,8 mm are measured
excluding copper and laminates greater or equal to 0,8 mm are measured including copper. If
the copper-clad laminate is tested in accordance with test method 2D01 of IEC 61189-2, the
thickness shall not depart from the nominal thickness by more than the appropriate value
shown in Table 2. The fine tolerances shall apply unless the other tolerances are ordered.
Table 2 – Nominal thickness and tolerance of metal-clad laminate
Nominal thickness excluding Nominal thickness including Tolerance requirements
metal foil (material intended metal foil (material intended
±mm
for multilayer boards) for single or double sided boards)
Coarse Fine Extra fine
mm mm
0,03 0,02 0,01
≥0,05 ≤ 0,10
0,04 0,03 0,02
>0,10 ≤ 0,15
0,05 0,04 0,03
>0,15 ≤ 0,30
0,08 0,05 0,04
>0,30 ≤ 0,50
0,09 0,06 0,05
>0,50 ≤ 0,80
0,13 0,09 0,07
≥0,80 ≤ 1,00
>0,80 ≤ 1,00
0,17 0,11 0,08
>1,00 ≤ 1,30
>1,00 ≤ 1,30
0,20 0,13 0,10
>1,30 ≤ 1,70
0,23 0,15 0,12
>1,70 ≤ 2,10
0,25 0,18 0,15
>2,10 ≤ 2,60
0,30 0,20 0,15
>2,60 ≤ 3,20
The thickness and tolerances do not apply to the outer 25 mm of the trimmed master sheet or
the outer 13 mm of the cut-to-size panel as manufactured and delivered by the supplier. At no
point shall the thickness vary from the nominal by a value greater than 125 % of the specified
tolerance.
6.4 Bow and twist
When the copper-clad laminate is tested in accordance with test method 2M01 of IEC 61189-2
the bow and twist shall not exceed the values given in Table 3.

– 10 – 61249-2-38 © IEC:2008
Table 3 – Bow and twist
Requirements
Nominal Panel dimension
Test method %
Property thickness longest side
(IEC 61189-2)
mm mm Copper foil on Copper foil on
one side both sides
Bow and 2M01 ≥0,8 ≤ 1,3 ≤350 ≤2,0 ≤1,5
twist
>350 ≤500 ≤1,8 ≤1,3
>500 ≤1,5 ≤1,0
>1,3 < 1,7 ≤350 ≤1,5 ≤1,0
>350 ≤500 ≤1,3 ≤0,8
>500 ≤1,0 ≤0,5
≥1,7 ≤ 3,2 ≤350 ≤1,0 ≤0,5
>350 ≤500 ≤0,8 ≤0,4
>500 ≤0,5 ≤0,3
NOTE The requirements for bow and twist apply only to one sided copper-clad laminates with maximum foil
thickness of 105 μm (915 g/m ) and double sided copper-clad laminates with maximum foil thickness difference of
70 μm (610 g/m ).
Requirements for laminates with copper foil configurations beyond these limits are subject to agreement between
purchaser and supplier.
6.5 Properties related to the copper foil bond
Pull-off and peel strength requirements are shown in Table 4. These requirements apply to
copper foil with a normal profile depth. In the case of low or very low profile copper foil, the
requirements shall be at least 50 % of that shown in Table 4 as a minimum.

61249-2-38 © IEC:2008 – 11 –
Table 4 – Pull-off and peel strength
Test method
Property Requirements
(IEC 61189-2)
Pull-off strength 2M05
≥25 N
Thickness of the copper foil
≤12 μm 18 μm 35 μm ≥70 μm
2 2
2 2
(152 g/m ) (305 g/m )
(≤101 g/m ) (≥610 g/m )
Peel strength after 2M14 ≥0,7 N/mm ≥0,9 N/mm ≥1,2 N/mm ≥1,6 N/mm
heat shock of 20 s
No blistering nor delamination
Peel strength after dry 2M15
≥0,7 N/mm ≥0,9 N/mm ≥1,2 N/mm ≥1,6 N/mm
o
heat 125 C
No blistering nor delamination
Peel strength after 2M06
exposure to solvent
vapour. Solvents as
≥0,7 N/mm ≥0,9 N/mm ≥1,2 N/mm ≥1,6 N/mm
agreed upon between
purchaser and supplier
No blistering nor delamination
Peel strength after 2M16
≥0,6 N/mm ≥0,8 N/mm ≥1,0 N/mm ≥1,2 N/mm
simulated plating
No blistering nor delamination
Peel strength at high 2M17
temperature
Not specified ≥0,7 N/mm ≥0,9 N/mm ≥1,1 N/mm
o
Temperature 125 C
(optional)
Blistering after 20 s heat 2C05
No blistering nor delamination
shock
NOTE In case of difficulty due to breakage of the foil or reading range of the force measuring device, the
measurement of peel strength at high temperature may be carried out using conductor widths of more than 3 mm.
6.6 Punching and machining
Punching is not applicable. The laminate shall, in accordance with the manufacturer’s
recommendations, be capable of being sheared or drilled. Delamination at the edges due to the
shearing process is permissible, provided that the depth of delamination is not larger than the
thickness of the base material. Delamination at the edges of drilled holes due to the drilling
process is not permissible. Drilled holes shall be capable of being through-plated with no
interference from any exudations into the hole.
6.7 Dimensional stability
The dimensional stability requirements are shown in Table 5. When specimens are tested in
accordance to IEC 61189-2, 2X02, the observed tolerance shall be as specified in Table 5. The
nominal dimensional stability value shall be as agreed upon between user and vendor. The
tolerance range around the agreed upon nominal thickness shall be range B unless otherwise
specified on the purchase order.
The choice of the glass fabrics in the construction of the laminate has a significant impact on
dimensional stability. Examples of typical constructions used in printed board applications can
be found in Annex B.
Class A performance shall apply unless otherwise noted on the purchase order.

– 12 – 61249-2-38 © IEC:2008
Table 5 – Dimensional stability
Test method Requirements
Property Class
(IEC 61189-2) ppm
Dimensional stability 2X02 A
±300
B
±200
C ±100
X As agreed upon between user and supplier

6.8 Sheet sizes
6.8.1 Typical sheet sizes
Sheet sizes are matters of agreement between purchaser and supplier. However the
recommended sizes are listed below:
– 915 mm × 1 220 mm;
– 1 065 mm × 1 155 mm;
– 1 065 mm × 1 280 mm;
– 1 000 mm × 1 000 mm;
– 1 000 mm × 1 200 mm.
6.8.2 Tolerances for sheet sizes
+20
The size of sheet delivered by the supplier shall not deviate more that mm from the ordered
size.
6.9 Cut panels
6.9.1 Cut panel sizes
Cut panel sizes shall be, when delivered, in accordance with the purchaser’s specification.
6.9.2 Size tolerances for cut panels
For panels cut to size according to the purchaser’s specification, the following tolerances for
length and width shall apply as shown in Table 6. Tolerances indicated as normal shall be in
effect unless otherwise specified by in the purchasing specification.
Table 6 – Size tolerance for cut panels
Tolerance requirements
Panel size
± mm
mm
Normal Close
2,0 0,5
≤300
2,0 0,8
>300 ≤600
2,0 1,6
>600
NOTE The specified tolerances include all deviations caused by cutting the panels.

61249-2-38 © IEC:2008 – 13 –
6.9.3 Rectangularity of cut panels
For panels cut to size according to the purchaser’s specification, the following requirements for
rectangularity shall apply as shown in Table 7. Tolerance indicated as normal shall be in effect
unless otherwise specified in the purchasing specification.
Table 7 – Rectangularity of cut panels
Requirements
Test method
mm/m
Property
(IEC 61189-2)
Normal Close
Rectangularity of cut panels 2M23 ≤3 ≤2

7 Non-electrical properties of the base material after complete removal of the
copper foil
7.1 Appearance of the dielectric base material
The etched specimens shall be inspected to verify that no surface or subsurface imperfections
of the dielectric material exceed those shown below. The panels shall be inspected using an
optical aid apparatus which provides a minimum magnification of 4X.
Referee inspection shall be conducted at 10X magnification. Lighting conditions of inspection
shall be appropriate to the material under inspection or as agreed upon between user and
supplier.
Surface and subsurface imperfections (such as weave texture, resin starvation, voids, foreign
inclusions) shall be acceptable provided that the imperfections meet the following:
• the reinforcement fibres are not cut or exposed;
• the foreign inclusions are not conductive;
• the imperfections do not propagate as a result of thermal stress;
• the foreign inclusions are translucent;
• opaque foreign fibres are less than 15 mm in length and average no more than one per
300 mm × 300 mm area;
• opaque foreign inclusions other than fibres shall not exceed 0,50 mm. Opaque foreign
inclusions less than 0,15 mm shall not be counted. Opaque foreign inclusions between
0,50 mm and 0,15 mm shall average no more than two spots per 300 mm × 300 mm area;
• voids (sealed voids or surface void) have a longest dimension less than 0,075 mm and
there should not be more than three voids in a 3,5 mm diameter circle.
7.2 Flexural strength
When the laminate is tested in accordance with test method 2M20 of IEC 61189-2 the flexural
strength shall be as shown in Table 8.

– 14 – 61249-2-38 © IEC:2008
Table 8 – Flexural strength
Test method
Property Requirements
(IEC 61189-2)
Flexural strength 2M20
Length direction
≥400 N/mm
Cross direction 2
≥300 N/mm
(applicable to sheets ≥1,0 mm in thickness)
Flexural strength
Length direction Not specified
Elevated temperature
(applicable to sheets ≥1,0 mm in thickness)

7.3 Flammability
When the laminate is tested in accordance with test method 2C08 (thickness ≥0,05 mm ≤
0,3 mm) or 2C06 (thickness >0,3 mm ≤ 3,2 mm) of IEC 61189-2, the flammability shall be as
shown in Table 9.
The performance labelled V-0 shall apply unless otherwise noted on the purchase order.
Table 9 – Flammability
Test method
Property Requirements
(IEC 61189-2)
Flammability
Designation
2C06
V-0
Flaming combustion time after each application of the flame for each
≤10 s
test specimen.
Total flaming combustion time for the 10 flame applications for each set
of five specimens.
≤50 s
Glowing combustion time after the second removal of the test flame.

Flaming or glowing combustion up to the holding clamp.
≤30 s
Dripping flaming particles that ignite the tissue paper
None
None
7.4 Water absorption
When the laminate is tested in accordance with test method 2N02 of IEC 61189-2, the
maximum water absorption shall be as shown in Table 10.
Table 10 – Water absorption
Test method Thickness Requirements
Property
mm
(IEC 61189-2) %
2N02
≥0,05 < 0,20 ≤2,00
Water absorption
≥0,20 < 0,30 ≤1,50
≥0,30 < 0,40 ≤1,20
≥0,40 < 0,50 ≤1,00
61249-2-38 © IEC:2008 – 15 –
Test method Thickness Requirements
Property
(IEC 61189-2) mm %
≥0,50 < 0,60 ≤0,80
≥0,60 < 0,80 ≤0,70
≥0,80 < 1,00 ≤0,50
≥1,00 < 1,20 ≤0,50
≥1,20 < 1,60 ≤0,40
≥1,60 < 2,00 ≤0,25
≥2,00 < 2,40 ≤0,20
≥2,40 < 3,20 ≤0,20
7.5 Measling
When the laminate is tested in accordance with test method 2N01 of IEC 61189-2, the
presence of measles allowed shall be as shown in Table 11.
Table 11 – Measling
Test method
Property Requirements
(IEC 61189-2)
Measling 2N01 No measling on three specimens. If one out of three
specimens fails, the test has to be repeated.
No measling on three specimens of the second test is
permitted.
No blistering or delamination on any of the three
specimens is permitted.
7.6 Glass transition temperature and cure factor
The requirements for glass transition temperature and cure factor are found in Table 12.
Table 12 – Glass transition temperature and cure factor
Test method
Property Requirements
(IEC 61189-2)
Glass transition temperature 2M10 or 2M11
≥120 °C
Cure factor 2M03 ≥0,96
7.7 Decomposition temperature
The requirements for decomposition temperature are found in Table 13.
Table 13 – Decomposition temperature
Test method
Property Requirements
(IEC 61189-2)
Decomposition temperature (5 % 2MXX
≥310°C
weight loss from 50 °C)
– 16 – 61249-2-38 © IEC:2008
7.8 Thermal resistance
The requirements for thermal resistance are found in Table 14. The specimen shall not have
copper foil on any layer.
Table 14 – Thermal resistance
Test method
Property Requirements
(IEC 61189-2)
T260 2MXX
≥30 min
T288 ≥5 min
T300 TBD
7.9 Z-axis expansion
The requirements for Z-axis expansion are found in Table 15.
Table 15 – Z-axis expansion
Test method
Property Requirements
(IEC 61189-2)
Z-axis alpha 1 2MXX -6 /
≤60 × 10 °C
-6
Z-axis alpha 2
≤300 × 10 / °C
Z-axis % 50 °C to 260 °C 4,0 % maximum

8 Quality assurance
8.1 Quality system
The supplier shall operate a quality system, ISO 9000 or similar, to support quality
conformance inspection.
The supplier shall operate a management system for environmental control, ISO 14000 or
similar, to support environmental considerations.
8.2 Responsibility for inspection
The supplier is responsible for all the inspections of the manufactured material. The purchaser
or an appointed third party may audit this inspection.
8.3 Qualification inspection
Laminates furnished under this standard shall be qualified. Qualification testing shall be
performed to demonstrate the manufacturer’s ability to meet the requirements of this standard.
Qualification testing shall be conducted at a laboratory in compliance with IEC laboratory
requirements. A list of the normal qualification tests can be found in Annex C. The
manufacturer shall retain on file the data which supports that the materials meet this standard
and shall be readily available for review upon request.
8.4 Quality conformance inspection
The supplier shall operate a quality plan to assure product conformance to this standard. Such
a quality plan, when appropriate, should utilize statistical methods rather than lot-by-lot
inspection. It is the responsibility of the supplier, based on the quality plan, to determine the
frequency of test to assure conforming products. In the absence of a quality plan or supporting
data, the testing regime shall be as outlined in Annex C.

61249-2-38 © IEC:2008 – 17 –
A combination of the following techniques may be used to show compliance with the
requirements which can be used to reduce the frequency of testing. The data supporting the
reduction of testing frequency shall be available for review upon request.
• In process parameter control
• In process inspection
• Periodic final inspection
• Final lot inspection
8.5 Certificate of conformance
The supplier shall, on request from the purchaser, issue a certificate of conformance to this
standard in electronic or paper format.
8.6 Safety data sheet
A safety data sheet in accordance with ISO 11014-1 shall be available for products
manufactured and delivered in compliance with this standard.
9 Packaging and marking
If not otherwise specified in the purchase order, laminate sheets shall be marked with the
manufacturer's designation and lot number. Marking shall remain legible during normal
handling but be readily removable prior to use of the material.
Cut-to-size panels shall be identified by marking on the package.
Laminates comprised of asymmetric copper configurations shall be marked on the side of
heaviest copper weight.
Sheets and panels shall be packaged in a manner which will provide adequate protection
against corrosion, deterioration and physical damage during shipment and storage.
Packages shall be marked in a manner to clearly identify the contents.
10 Ordering information
Order shall include the following details:
a) A reference to this specification
b) Type of material (see scope and 7.3)
c) Size, thickness and copper cladding
d) Class of indentations if other than “A” (see 6.1.1).
e) Class of raised areas if other than “A” (see 6.1.4).
f) Class of thickness tolerance if other than “fine” (see 6.3).
g) Class of dimensional stability if other than “A” (see 6.7).
h) Class of panel size tolerance if other than “normal” (see 6.9.2).
i) Request for certification if applicable (see 8.5)

– 18 – 61249-2-38 © IEC:2008
Annex A
(informative)
Engineering information
A.1 General
Information in this annex does not detail material property requirements. The information is
intended as a guideline for design and engineering purposes. Users of this standard are
encouraged to supply information to be included in the annex.
Materials according to this standard show the properties and data as listed in Clause A.2 to
Clause A.7.
A.2 Chemical properties
• Resistance against chemicals
A.3 Electrical properties
• Comparative tracking index 175 – 250 V
A.4 Flammability properties
• Needle flame test
• Oxygen index 45 %
A.5 Mechanical properties
• Compressive strength (flatwise)  400 N/mm
• Compressive strength (edgewise)  240 N/mm
• Hardness at room temperature 200 (Rockwell M)
• Modulus of elasticity, flexural (warp) 1,9 × 10 N/mm
• Modulus of elasticity, flexural (weft) 1,5 × 10 N/mm
• Modulus of elasticity, tensile (warp) 1,7 × 10 N/mm
• Modulus of elasticity, tensile (weft) 1,4 × 10 N/mm
• Poisson’s ratio 0,12 - 0,16
• Shear strength 148 N/mm
• Young’s modulus 22 GPa
61249-2-38 © IEC:2008 – 19 –
A.6 Physical properties
• Density 1,85  g/cm
A.7 Thermal properties
–6
• Coefficient of thermal expansion ( –6
• Coefficient of thermal expansion ( • Specific heat capacity 1,25 kJ/kg ⋅ °C
• Thermal conductivity 0,3 W/m ⋅ °C
• UL temperature index (mechanical) 130 °C
• UL temperature index (electrical) 130 °C
• Maximum operating temperature (MOT) 130 °C

– 20 – 61249-2-38 © IEC:2008
Annex B
(informative)
Common laminate constructions
Nominal thickness
Common construction
mm
0,075 1 080
0,080 2 × 106
0,100
2 × 106
0,100 2 113
0,100 2 116
0,125 2 116
0,125 2 165
0,125
2 × 1 080
0,15 2 157
0,15 2 165
0,16 1 500
0,18 7 628
0,18 1 500
0,20 2 × 2 113
0,20
2 × 2 116
0,20 7 628
0,25
2 × 2 116
0,25
2 × 2 165
0,26 1 080/2 116/1 080
0,30
2 × 2 157
0,30 2 × 2 165
0,30 2 116/2 112/2 116
0,30
1 080/7 628/1 080
0,36
2 × 7 628
0,37 2 113/7 628/2 113
0,38 1 500/1 080/1 500
0,41 7 628/1 080/7 628
0,43 2116/7628/2116
0,45
3 × 1 500
0,46 7 628/2 112/7 628
0,48 7 628/2 116/7 628
0,51 7 628/2 165/7 628
0,51 1 080/2 × 7 628/1 080
0,54
3 × 7 628
0,61
3 × 7 628/1 080
0,61 2 116/2 × 7 628/2 116
0,66
7 628
...