Cover coating with good adhesion on polyurethane and polyurea membranes
AssigneeSika Technology AG
InventorsSteven Dawn, Michael Byrne, Alexander Coward
Life of this patent
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Abstract
A composition includes a first component containing at least one polyaspartic acid ester (P1-1) and optionally a polyaspartic acid ester (P1-2) and a mixture of various polyetheraspartic acid esters (P2), and of a second component containing at least one aliphatic polyisocyanate (B1) and at least one isocyanate prepolymer (B2). The composition is particularly suitable as a cover coating composition. Said composition has a good adhesion on polyurea and polyurethane membranes, in particular roof membranes, and has drying times of less than 120 min, an elongation at break of 80-200% and a tensile strength of more than 6 N/mm2.
Claims16
A composition consisting of
- a first component comprising:
- at least one polyaspartic ester P1-1
- of the formula (II);
- optionally a polyaspartic ester P1-2
- of the formula (III);
- a mixture of different polyether aspartic esters P2 having the following formula:
- where X is the residue of a polyether polyamine having a repeat unit of the structure
- where m=2 to 35,
- and a second component comprising:
- at least one aliphatic polyisocyanate B1;
- at least one isocyanate prepolymer B2;
- where:
- the polyaspartic ester P1-1, the polyaspartic ester P1-2 and the mixture of different polyether aspartic esters P2 are present in such an amount that the weight ratio ((P1-1+P1-2)/P2) is ≤1.5, and
- the weight ratio P1-1/P1-2 is ≥0.65, and
- the weight ratio B1/B2 is in the range of 0.7-3.0.
Dependencies are inferred from the claim text.