Calofort® SM

Calofort® SM by Specialty Minerals is a precipitated calcium carbonate. It is stearate coated white microcrystalline powder characterized by high surface area, controlled particle shape and high whiteness. It consists of fine calcitic crystals with an average particle size of 0.07µm. Used in sealant systems based upon polyurethane, polysulphide and other polymers where slump resistance as well as viscosity control are important. It can allow partial or total replacement of more expensive thixotropic aids. Its surface promotes hydrogen bonded networks when used in sealant formulations. These structures readily break down under shear, leading to a reduced viscosity and hence a more readily pumped or sprayed product. However, on removal of the shear, the sealant structure quickly recovers giving rise to good slump resistance. The fine particle size of Calofort® SM also acts as a reinforcing agent which gives the benefit of high tear and tensile strength in the cured product.