According to reports, two new calcium stearates have become preferred choices for improving the surface quality of rigid PVC (polyvinyl chloride) window-frame profiles and polyolefin packaging films. Grades 500 and 600 were developed by the Organic Specialty Chemicals Group of Ferro Corporation in Ohio, USA. In addition to retaining their functions as acid scavengers and lubricants, these calcium stearates improve product quality in use and correct surface defects. They can also increase polyolefin fiber output by reducing the frequency of cleaning caused by die plugging. Compared with high-cost precipitated products, these two calcium stearates are clearly more economical. Both powdered and granular forms are available.