The reason that this is such a big deal is that Pb-free wave soldering has been a challenge to obtain good hole fill while not leaving behind harmful residues. The WF-9945 is the first flux of its kind to achieve that while also not containing any halogens.
As shown in the test results here, the WF-9945 is halogen-free using the oxygen bomb following by ion chromatography test method (EN14582).
For more information about this product and its performance attributes, contact Indium's technical service team at 800-4-INDIUM.