External Release Agent for use in unsaturated polyester resins: Release Agents are special products, which are used in the UP industry to enable a demoulding of the cured UP part from the mould. Release Agent NL-1 is a waxy paste, which must be applied as a first thin coat on the mould. After application the wax layer should be polished thoroughly. It is not necessary to renew the NL-1 layer after each demoulding. The number of demouldings in which the same wax layer will serve before it has to be renewed, depends on the material of which the mould is made, the demoulding time and the method of cleaning the mould. If the mould is washed out with water, containing detergents, renewal of the wax layer is necessary after each washing.