85N
High Temperature Polyimide
General Information
Arlon’s 85N is a 250⁰C high glass transition pure polyimide resin system which provides superior thermal resistance to high temperature end-use electronics. Coupled with the high temperature stability and the pure resin formulation, 85N is the best choice for high layer count multilayers with long service life for aerospace, military, space and other applications where reliable thermal stability is required. Meets requirements of IPC-4101/40 and IPC-4101/41.
Detailed Specs
Process inner-layers through develop, etch, and strip using standard industry practices. Use brown oxide on inner layers.
Adjust dwell time in the oxide bath to ensure uniform coating.
Bake inner layers in a rack for 60 minutes at 107°C - 121°C (225°F - 250°F) immediately prior to lay-up.
Store prepreg at 60-70°F at or below 30% RH.
Vacuum desiccate the prepreg for 8 - 12 hours prior to lamination.
Lamination Cycle:
- Pre-vacuum for 30 - 45 minutes
- Control the heat rise to 4.5°C - 6.5°C (8°F - 12°F) per minute between 100°C and150°C (210°F and 300°F). Vacuum lamination is preferred. Start point vacuum lamination pressures are shown in the table below.
- Set cure temperature at 218˚C (425˚F). Start cure time when product temperature > 213˚ C (415˚F)
- Cure time at temperature = 120 minutes
- Cool down under pressure at ≤ 5°C/min (10°F/min)
- Drill at 350 SFM. Undercut bits are recommended for vias 0.0 18” (0.45mm) and smaller
- De-smear using alkaline permanganate or plasma with settings appropriate for polyimide; plasma is preferred for positive etchback
- Conventional plating processes are compatible with 85N
- Standard profiling parameters may be used; chip breaker style router bits are not
recommended - Bake for 1 - 2 hours at 250°F (121°C) prior to solder to reflow of HASL
IPC VALIDATION SERVICES – QUALIFIED PRODUCT LISTING (QPL )
Arlon EMD is the first U.S. laminator recognized under IPC’s Quality Product Listing. We are the only laminator to have achieved certification for all three slash sheets on polyimide materials, IPC-4101/40, IPC-4101/41 and IPC-4101/42.