• High Reliability
• Reliable residues in harsh modified SIR testing
• Consistent print performance down to 0.55 area ratio in all print conditions
• Excellent solderability and wetting across varied profiles - Similar performance in air vs. N2 - Resistance to tombstoning
• Low voiding across wide variety of profiles
• Compatible with multiple conformal coatings
• Extremely stable paste properties - No loss in print performance after 30°C/70%RH for 7 days
• Passed the Bono Corrosion Test with a corrosion factor (Fc) value of 1.1%

Kester NP505-HR is a zero-halogen, lead-free, no-clean solder paste formula developed specifically for high reliability applications. NP505-HR has been formulated to have reliable residues even in harsh damp cycling SIR testing. NP505-HR can handle a wide variety of printer variables, including print speed and long idle times with a wide range of temperatures and humidities. NP505-HR is fully capable of printing and reflowing 01005 components in air reflow with minimal graping behavior. Post-soldering, the NP505-HR offers minimized defects, including head-in-pillow and QFN/BGA voiding. This paste is zero-halogen, exceeding the IPC definition for halogen-free. NP505-HR is classified as ROL0 per IPC J-STD-004B. NP505-HR is part of Kester’s high reliability product line and compatible with no-clean RF550 Rework Flux, NF372-TB Solder Flux and SELECT-10™ Selective Soldering Flux.
Flux for High-Reliability Applications