Mehrschichtiger Lackauftrag mit gradierenden Eigenschaften fuer flexible Substrate

EP 1352936 A UPAB: 20040218 NOVELTY - A flexible substrate (I) comprises a coating (II) having graded properties and consisting of at least a base layer and a covering layer whereby both layers are prepared by means of hydrolysable and condensable silanes such that the base layer is more flexible than the covering layer while the covering layer has greater abrasion resistance than the base layer. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a process for the coating of the substrate (I) with a coating (II) comprising application of a base layer onto the substrate, prepared by hydrolytic condensation of at least one silane of formula (1) in the presence of at least one silicon free compound that has at least 4C atoms when the coating does not contain a compound of formula (1) having an R group; application of a covering layer prepared by hydrolytic condensation of at least one silane of formula (2) as well as optionally a hydrolysable and co-condensable metal compound of formula (3) without addition of a pure organic compound; and, drying and/or hardening of the base and the covering layers. (2) a kit comprising a silane of formula (1), a silane of formula (2) and optionally a metal compound of formula (3). RaR'bSiX4 - a - b (1) RxaRybSiX4 - a - b (2) M(OR)x (3) R' = at least 4C alkyl or alkenyl group; R1 = R1, R2 or R3; R1 = at least 4C alkyl; R2 = NR4R5; R3 = organic polymerizable group ;that is bonded to the Si atom by a carbon atom; R4 = H or 1-4C alkyl; R5 = 1-8C alkylene; X = leaving group that preferably under hydrolytic conditions enables the formation of Si-O-Si groups; a = 0-2; b = 1-2; a+b = 1-3; Rx = 1-10C alkyl or alkenyl; Ry = R3; M = 3- or 4-valent metal that is complexable by alcoholate groups; OR = alcoholate groups, preferably methoxy or ethoxy; x = 3 or 4 USE - The flexible substrate (I) is useful for the production of clothing, bags, furniture leather. ADVANTAGE - The substrate (I) has improved water and abrasion resistance