Strontium Octoate is the replacement of Lead Octoate, where Lead free Paint/Ink is required. It improves through drying in adverse effect like high humidity & low temperatures. Strontium seems to overcome the insufficient Zirconium performance. Also unlike Zirconium, Strontium avoids yellowing. Strontium is also a good pigment wetting & dispersing agent preventing haze & wrinkling.