Pigmented primer composition

Claim 1

A COMPOSITION USEFUL FOR PRIMING POROUS SURFACES COMPRISING A THERMOPLASTIC POLYESTER RESIN CHARACTERIZED PHYSICALLY BY A MELTING POINT IN THE RANGE OF 100*-120*C, A VISCOISTY IN 35 PERCENT AMMONIACAL SOLUTION OF ABOUT 30-50 CPS, SOLUBILITY A ALKALINE PH, SOLUBILITY IN ALKANOLS HAVING 1 TO 4 CARBON ATOMS, AND CHAACTERIZED CHEMICALLY AS THE POLYMERIZATION PRODUCT OF TRIMELLITIC ANHYDRIDE AND ISOPHTHALIC ACID IN A MOLAAR RATIO OF ABOUT 4-8 TO 1, A GLYCOL HAVING 3 TO 6 CARBON ATOMS IN AN AMOUNT OF 0.7 TO 1.2 MOLES PER MOLE OF TRIMELLITIC ANHYDRIDE, AND AN ALKANOL HAVING 6 TO I6 CARBON ATOMS IN AN AMOUNT SUFFICIENT TO IMPART TO THE RESIN AND ACID NUMBER OF ABOUT 190-210; DISSOLVED IN A LOWER ALKANOL HAVING 1 TO 4 CARBON ATOMS, THE WEIGHT RATIO OF SAID LOWER ALKANOL TO SAID RESIN BEING IN THE RANGE OF 0.5-4 TO 1, AND HAVING DISPERSED THEREIN 5 TO 60 PERCENT BY WEIGHT OF AT LEAST ONE PIGMENT; THE PH OF SAID COMPOSITION BEING IN THE RANGE OF 3 TO 6.5.

Claim 12

The method of finishing a porous surface comprising first applying thereto a thin coat of a primer composition comprising a thermoplastic polyester resin characterized physically by a melting point in the range of 100*-120*C, a viscosity in 35 percent ammoniacal solution of about 30-50 cps, solubility at alkaline pH, solubility in alkanols having 1 to 4 carbon atoms and characterized chemically as the polymerization product of trimellitic anhydride and isophthalic acid in a molar ratio of about 4-8 to 1; a glycol having 3 to 6 carbon atoms in an amount of 0.7 to 1.2 moles per mole of trimellitic anhydride and an alkanol having 6 to 16 carbon atoms in an amount sufficient to impart to the resin an acid number of about 190-210; dissolved in a lower alkanol having 1 to 4 carbon atoms, the weight ratio of such alkanol to said resin being in the range of 0.5-4 to 1, and having dispersed therein 5 to 60 percent by weight of at least one pigment; the pH of said composition being in the range of 3 to 6.5, drying said applied primer composition and then applying to said primed surface a thin layer of a finish coat.

Claim 13

The method of finishing a porous surface comprising first applying thereto a thin coat of a primer composition comprising a thermoplastic polyester resin characterized physically by a melting point in the range of 100*-120*C, a viscosity in 35 percent ammoniacal solution of about 30-50 cps, solubility at alkaline pH, solubility in alkanols having 1 to 4 carbon atoms and characterized chemically as the polymerization product of trimellitic anhydride and isophthalic acid in a molar ratio of about 4-8 to 1; a glycol having 3 to 6 carbon atoms in an amount of 0.7 to 1.2 moles per mole of trimellitic anhydride and an alkanol having 6 to 16 carbon atoms in an amount sufficient to impart to the resin an acid number of about 190-210; dissolved in a lower alkanol having 1 to 4 carbon atoms, the weight ratio of such alkanol to said resin being in the range of 0.5-4 to 1, and having dispersed therein 5 to 60 percent by weight of at least one pigment; the pH of said composition being in the range of 3 to 6.5, drying said applied primer composition and then applying to said primed surface a thin layer of a finish coat.