IEC PAS 61249-6-3:2011

IEC/PAS 61249-6-3 ®
Edition 1.0 2011-09
PUBLICLY AVAILABLE
SPECIFICATION
Specification for finished fabric woven from “E”glass for printed boards

IEC/PAS 61249-6-3:2011(E)
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IEC/PAS 61249-6-3 ®
Edition 1.0 2011-09
PUBLICLY AVAILABLE
SPECIFICATION
Specification for finished fabric woven from “E”glass for printed boards

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
T
ICS 31.180 ISBN 978-2-88912-699-6

– 2 – PAS 61249-6-3 © IEC:2011(E)
CONTENTS
FOREWORD . 4
1 Scope . 6
1.1 Purpose . 6
1.2 Designation . 6
2 Normative references . 6
2.1 IPC . 6
2.2 American Society for Testing and Materials (ASTM) . 6
2.3 International Standards . 6
2.4 National Conference of Standards Laboratories (NCSL) . 6
3 Terms and definitions . 6
4 Requirements . 9
4.1 Yarn nomenclature . 9
4.1.1 US system . 9
4.1.2 SI/metric . 9
4.1.3 Conversion from US system to SI . 10
4.2 Visual requirements . 10
4.3 Physical requirements . 10
4.3.1 Fabric count . 10
4.3.2 Weave type . 10
4.3.3 Fabric thickness . 10
4.3.4 Fabric weight . 10
4.3.5 Fabric length . 10
4.3.6 Fabric width . 11
4.3.7 Feather length . 11
4.3.8 Filament diameter . 11
4.3.9 Bare glass nominal measurement . 12
4.4 Chemical requirements . 12
4.4.1 Finish level (organic content) . 12
4.5 Workmanship . 12
4.6 Laser machinability performance . 12
4.7 Alternate fabric styles and weaves . 12
5 Quality assurance . 13
5.1 Statistical process control (SPC) . 13
5.2 Responsibility for inspection . 13
5.2.1 Test equipment and inspection facilities . 14
5.2.2 Preparation of samples . 14
5.2.3 Standard laboratory conditions . 14
5.3 Inspection requirements and acceptability . 14
5.3.1 Sample size . 14
5.3.2 Sampling plans . 15
5.3.3 Acceptable quality level (AQL) . 15
5.4 Test methods . 15
5.4.1 Fabric appearance . 15
5.4.2 Fabric count . 15
5.4.3 Weave type . 16
5.4.4 Fabric thickness . 16

PAS 61249-6-3 © IEC:2011(E) – 3 –
5.4.5 Weight per unit area . 16
5.4.6 Fabric length . 17
5.4.7 Fabric width . 17
5.4.8 Finish level (organic content) . 17
5.4.9 Bias or bowed filling . 17
6 Preparation for delivery . 18
6.1 Preservation and packaging . 18
6.2 Packing . 18
6.3 Marking . 18
7 Notes . 18
7.1 Ordering data . 18
7.2 New Styles . 18
Annex A . 19
Annex B Finished Fabric Glass Styles . 21

Table 1 – Classification of Defects . 11
Table 2 – Filament Diameter Designations . 11
Table 3 – Bare Glass Nominal Measurements . 12
Table 4 – Sample Size per Number of Rolls Shipped . 14
Table 5 – Sample size per yardage of individual roll shipped and the acceptable
quality level . 14
Table A.1 – Cross Reference Between IPC-4412, Standards Called Out by IPC-4412,
and ISO Documents . 19
Table A.2 – Cross Reference Between IPC-4412, ASTM and ISO Documents. 19
Table B.1 – Finished Fabric Glass Styles in SI Units . 21
Table B.2 – Finished Fabric Glass Styles for US System . 24

– 4 – PAS 61249-6-3 © IEC:2011(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SPECIFICATION FOR FINISHED FABRIC
WOVEN FROM “E”GLASS FOR PRINTED BOARDS

FOREWORD
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A PAS is a technical specificati
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