Silicon and zirconium based lacquer, its use as a substrate coating and substrates thus obtained

A lacquer obtained by a process comprising the steps of:

• (i) precondensing:
• a) 1 to 10 mol% of at least one zirconium compound of the formula I:
• ZrR.sub.4 (I)
• wherein:
• R is halogen, hydroxy, alkoxy, acyloxy or chelated ligand;
• b) 20 to 94 mol% of at least one organic silane of the formula II:
• R".sub.m (R"'Y).sub.n SiX.sub.(4-m-n) (II)
• wherein:
• R" is alkyl, alkenyl, aryl, alkylaryl, arylalkyl, alkenylaryl, or arylalkenyl;
• R"' is alkylene, alkenylene, arylene, alkylarylene, aryl-alkylene, alkenyl-arylene, or arylalkenylene;
• R" and R"' being optionally interrupted by oxygen, sulfur or --NH--;
• X is hydrogen, halogen, hydroxy, alkoxy, acyloxy, or --NR'.sub.2 where R' is hydrogen or alkyl;
• Y is a polymerizable group;
• m is an integer from 0 to 3 and n is an integer from 1 to 3;
• m+n is from 1 to 3;
• and
• c) 5 to 30 mol% of at least one organic silane of formula III:
• R".sub.p SiX.sub.4-p (III)
• wherein R" and X are defined in b), and p is 1, 2 or 3;
• and
• d) 0 to 10 mol% of at least one low-volatility metal oxide, soluble in the precondensation reaction medium, of an element of groups Ia to Va or IVb or Vb of the Periodic Table of the Elements, or a compound of one of these elements, soluble in the reaction medium, forming a low-volatility oxide;
• optionally in the presence of an organic solvent at a temperature of between 10.degree. and 80.degree. C. for a period of time ranging from between 0.5 and 72 hours;
• and
• ii) condensation the precondensate of step (i) without water or with up to 50% of the stoichiometric amount of water, at a temperature of between 20.degree. and 90.degree. C. for a period of time from between 0.5 and 72 hours.