Process for strengthening the adhesion of polymeric substances to carbonate surfaces

A process for strengthening the adhesion of a polymeric substance which contains organic groups or are made up of such groups, or a substance containing organic groups which can be crosslinked to form a polymer, to a surface containing an inorganic carbonate, which comprises applying, a solution containing an organic aprotic solvent and a phsophorus compound to a surface containing an inorganic carbonate, in which the phosphorus compound is selected from the group consisting of phosphorus acid and a phosphorus-containing organosilicon compound having at least one group of the formula

• RSiOP.dbd.O,
• in which R is an SiC-bonded radical selected from the group consisting of a monovalent unsubstituted hydrocarbon radical and a monovalent substituted hydrocarbon radical, removing the solvent and thereafter applying the polymeric substance to the treated surface containing the inorganic carbonate, said phosphorus-containing organosilicon compound is selected from the group consisting of (1)
• (RR.sup.1.sub.2 SiO).sub.3 P.dbd.O,
• in which R is the same as above, R.sup.1 is a radical selected from the group consisting of an SiC-bonded monovalent unsubstituted hydrocarbon radical, a monovalent substituted hydrocarbon radical, an alkoxy radical, an alkoxyalkylenoxy radical having from 1 to 4 carbon atoms per radical, radicals of the formula
• R.sub.3 SiO.sub.1/2,
• in which R is the same as above, radicals having from 2 to 10 siloxane units of the formula
• RSiO.sub.3/2, R.sub.2 SiO or SiO.sub.4/2,
• in which R is the same as above and mixtures of at least 2 such siloxane units and (2) a compound obtained from the reaction of a silane of the formula
• RSi(OR.sup.2).sub.3,
• in which R is the same as above, R.sup.2 is selected from the group consisting of an alkyl radical having up to 4 carbon atoms per radical, an alkoxyalkylene radical having up to 4 carbon atoms per radical and partial hydrolyzates thereof containing at most 15 silicon atoms per molecule, with a phosphorus compound selected from the group consisting of orthophosphoric acid, phosphorus acid, phosphorus pentoxide and mixtures thereof, in which the reaction product contains from 0.005 to 0.33 phosphorus atom per silicon atom in the organosilicon compound.