Unsaturated polyester coating compositions having controlled resistance to penetration

Claim 1

AS AN ARTICLE OF MANUFACTURE, A POROUS SUBSTRATE COATED WITH A CURED FILM OF THE COATING COMPOSITION WHICH IS A FILLABLE VEHICLE CONSISTING ESSENTIALLY OF A 100% POLYMERIZABLE LIQUID MASS COMPOSED ESSENTIALLY OF: (A) AN UNSATURATED POLYESTER RESIN COMPONENT WHOSE MOLECULES CONTAIN A PLURALITY OF POLYMERIZABLE-REACTIVE $2,3-ENEDIOYL GROUPS DISSOLVED IN (B) ABOUT 7.2%-39% BY WEIGHT OF SAID POLYESTER COMPONENT, OF LIQUID COPOLYMERIZABLE AND MONOMERIC VINYLIC HYDROCARBON SELECTED FROM THE GROUP CONSISTING OF STYRENE, DIVINYL BENZENE, AND NUCLEARLY-SUBSTITUTED STYRENES, AND (C) BETWEEN ABOUT 0.5% AND 10% BY WEIGHT OF SAID POLYESTER/MONOMER SOLUTION OF FINELY-DIVIDED SOLID HYDROUS INORGANIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF DEHYDRATED SILICA GEL HAVING A SIO2 CONTENT OF 99.0-99.7% BY WEIGHT ON A DRY BASIS, SHORT ABSESTOS FIBER, NATURAL OPALINE MINERALS, HYDROUS CLAYS, AND MIXTURES THEREOF, SAID HYDROUS INORGANIC MATERIAL BEING DISPERSED IN SAID LIQUID VEHICLE OF POLYESTER/MONOMER SOLUTION AND BEING EFFECTIVE TO IMPART GOOD-HOLD-OUT TO THE COATING COMPOSITION AS COMPARED WITH THE SAME COATING FROM WHICH SAID INORGANIC MATERIAL HAS BEEN OMITTED.