The Thixotropic Alkyd Oil Primer is a modern twist on an established formula. The alkyd content means that whilst it is still linseed oil based, the oil has been modified to reduce cracking and increase flexibility. The white appearance comes from two pigments: Titanium Dioxide and Calcium Carbonate and the result is a highly opaque primer with good covering power. Thixotropic materials are those who stiffness can be reduced with the energy of a brush or knife, but not permanently. If you stop stirring, the thixotropic nature of the primer means it will quickly regain its body or structure.