ASSOCIATION CONNECTING ELECTRONICS …

1 IPC-HDBK-830 Guidelines for design , selection and Applicationof conformal CoatingsDeveloped by the conformal coating Handbook Task Group (5-33c) ofthe Cleaning and coating Committee (5-30) of IPCU sers of this standard are encouraged to participate in thedevelopment of future :IPC2215 Sanders RoadNorthbrook, Illinois60062-6135 Tel 847 847 CONNECTINGELECTRONICS INDUSTRIES Table of .. and Definitions .. 12 QUALIFICATION AND SPECIFICATIONREFERENCES OF International Standards .. Aviation Regulations (FAR) .. Standards .. Industry Standard.

2 Standards .. Laboratories .. Standards .. Standards (DSTAN, UK DefenceStandardization) .. Standards .. Equipment Manufacturing (OEM)Specification .. 53 ENVIRONMENTAL, HEALTH AND .. of Hazardous Waste .. Regulations .. 54 TYPES OF conformal 54-1AR Acrylic .. Epoxy .. Silicone .. Polyurethane .. Poly-para-xylelene (parylene) .. Systems (Acrylic/Polyurethaneand Other Combinations) .. and Solvent Cure .. Types of conformal Coatings .. (FC) .. 85 design FOR coating Philosophy .. Reliability Requirements.

3 The Product Life Cycle .. the Product Environment .. \Printed Circuit Boards .. Surfaces .. Surface Finishes .. Mask .. Material Type .. Components .. SMT Components .. SMT Components .. Voltage (HV)/High Current (HC) .. and Microwave .. Speed Digital .. Impedance .. Coverage .. & design Guidelines .. 146 RAW MATERIALS .. Measurements .. vs. Rheology .. Cup Measurements .. of Temperature .. Properties .. with Process Materials .. Masks .. Residues .. Media .. Release Agent.

4 Masking .. of Inhibition .. of Inhibition .. of Inhibition .. Check List .. 19 October .. Finishes .. Adhesion .. of Assessing Compatibility .. Assessment Techniques .. Environment .. Preparation .. Treatment .. Etching .. of Masks .. vs. Automated Masking .. Coverage .. Thickness .. coating Thickness .. and Point Coverage .. Method .. Consideration .. Consideration .. Techniques .. Techniques .. Adjustment .. of Viscosity Adjustment .. of Viscosity Adjustment .. Methods.

5 Spraying .. Spraying .. coating .. Deposition (XY) .. Mechanisms .. Temperature Cure .. Cure .. Accelerable .. Cure .. Cure .. Cure .. Process Considerations .. By-Products .. Surface Cure/Solvent Entrapment .. Cure Recommendations .. Process Monitoring .. Guidelines .. Source .. , Health and SafetyProcessing Considerations .. Adjustment .. and Brushing .. Deposition .. 369 FILM .. Properties .. Withstanding Voltage (DWV) .. Resistance .. Constant and Dissipation Factor.

6 Properties .. Stability .. Shock .. Transition Temperature (Tg) .. of Thermal Expansion (CTE) .. Gradient .. Resistance .. Creep .. Stability .. Compatibility andChemical Resistance .. Resistance .. Compatibility .. Resistance .. Resistance .. Resistance .. 40 IPC-HDBK-830 October Stability .. Resistance .. 4110 REWORK AND Methods .. Abrasion .. Blasting .. Ice Abrasion .. Degradation .. Rework Methods .. After Stripping .. , Health and Safety Reworkand Repair Considerations .. 4311 END USE Environment.

7 (UV) Radiation .. Gases .. Rain .. and Coastal Environment .. Environment .. on the Ground .. Outside The PressureContainment CompartmentDuring Operations .. Inside The PressureContainment CompartmentDuring Operations .. Environment .. Environment .. Environment .. Biological Chemical WarfareEnvironment .. 4612 LONG TERM RELIABILITY AND Mechanism .. of Transparency/Discoloration .. of Adhesion .. Chemical Attack .. Testing .. Parameters .. of Tests .. 48 APPENDIX A conformal coating 49 APPENDIX B Flow Cup Viscosity 52 APPENDIX C Troubleshooting 53 APPENDIX D Thermal 57 APPENDIX E Relative 58 APPENDIX F Time of 59 APPENDIX G Atmospheric 60 APPENDIX H Airborne 62 APPENDIX ISimulated Acid Rain 66 APPENDIX J coating for Medical 68 APPENDIX K Example of Stringent Test for AnyBreach in A conformal 71 FiguresFigure 4-1 conformal coating Family Trees.

8 6 Figure 5-1 Assembly Drawing with MaskingRequirements .. 15 Figure 8-1 Options of Cleaning Systems Accordingto Flux Type .. 22 Figure 8-2 Cure Windows of Primer Cure .. 23 Figure 8-3 Conditions that Influence the Extentof Primer Cure .. 24 Figure 8-4 Influence of Temperature and Humidity .. 24 Figure 8-5 Masking Tapes .. 26 Figure 8-6 Masking Boots .. 26 Figure 8-7 Spray Booth with a Manual Spray Gun .. 29 Figure 8-8 Nonatomized Curtain Coater .. 30 Figure 8-9 Swirl Applicator .. 30 Figure 8-10 Improvements in spray technology nowpermit pattern widths as tight as mm[125 mil] for work around sensitive keep-outareas.

9 30 Figure 8-11 Conveyorized Applicator .. 31 Figure 8-12 Stand-Alone Batch Applicator .. 31 Figure 8-13 Automated Applicator .. 32 Figure 8-14 Dipping Equipment with Smaller PCAs .. 32 Figure 8-15 Dipping Equipment with Large PCAs .. 32 Figure 8-16 Vapor Deposition Polymerization Unit .. 33 October 2002 IPC-HDBK-830viiFigure 8-17 Loss of conformal coating Adhesion .. 35 Figure 8-18 Voids in conformal coating .. 36 TablesTable 11-1 Temperature Classificationsof Automotive Industry .. 45 Table B-1 Conversion Chart for Flow Cup ViscosityMeasurements.

10 52 Table C-1 Troubleshooting Guide .. 53 Table D-1 Molecular Interpretation .. 57 Table D-2 Measurement Methods .. 57 Table E-1 Critical Relative Humidity (CRH) For SeveralInorganic Compounds .. 58 Table F-1 Time of Wetness .. 59 Table G-1 Deposition Rates for Particles .. 61 Table H-1 Ambient Air Pollution Levels .. 62 Table H-2 Dry Deposition Measurements .. 63 Table H-3 Highest Levels of Wet Deposition .. 64 Table H-4 Concentration of Selected Gaseous AirConstituents in US .. 64 Table H-5 Indoor Pollution Levels in the Far East .. 65 Table I-1 Acid Rain Formula for Testing Purposes.