Coating composition, a process for coating plastic substrates and the coated plastic substrates obtained therefrom

A process for coating a plastic substrate which comprises applying to said plastic substrate a coating composition which, comprises a one- or two-component binder and, in addition,

• a) 0.1 to 15.0% by weight, based on the weight of the binder, of at least one coupling agent based on a chemically modified, amorphous polyolefin having an average molecular weight of 10,000 to 100,000, a non-uniformity of 1.0 to 6.5, a chlorine content of 2.5 to 50% by weight and a total content of nitrogen, oxygen, sulfur and silicon, in the form of chemically incorporated functional groups, of about 2.5 to 15% by weight, and
• b) 2.5 to 35% by weight, based on the weight of the amorphous polyolefin, of a compound corresponding to the formula ##STR11## wherein A is a difunctional radical corresponding to the following formulae ##STR12## and R.sub.1 and R.sub.2 may be the same or different and represent a saturated aliphatic hydrocarbon radical containing 1 to 8 carbon atoms, a hydroxylakyl radical containing 2 to 6 carbon atoms provided that at least two carbon atoms are arranged between the hydroxyl group and the oxygen atom, or a radical corresponding to the formula ##STR13## wherein o is 0, 1 or 2 and p is an integer from 1 to 3, provided that the sum of o+p=3.

A coated plastic substrate which is prepared by a process which comprises applying to a plastic substrate a coating composition which, comprises a one- or two-component binder and, in addition,

• a) 0.1 to 15.0% by weight, based on the weight of the binder, of at least one coupling agent based on a chemically modified, amorphous polyolefin having an average molecular weight of ]0,000 to 100,000, a non-uniformity of 1.0 to 6.5, a chlorine content of 2.5 to 50% by weight and a total content of nitrogen, oxygen, sulfur and silicon, in the form of chemically incorporated functional groups, of about 2.5 to 15% by weight, and
• b) 2.5 to 35% by weight, based on the weight of the amorphous polyolefin, of a compound corresponding to the formula ##STR14## wherein A is a difunctional radical corresponding to the following formulae ##STR15## and R.sub.1 and R.sub.2 may be the same or different and represent a saturated aliphatic hydrocarbon radical containing 1 to 8 carbon atoms, a hydroxyalkyl radical containing 2 to 6 carbon atoms provided that at least two carbon atoms are arranged between the hydroxyl group and the oxygen atom, or a radical corresponding to the formula ##STR16## wherein o is 0, 1 or 2 and p is an integer from 1 to 3, provided that the sum of o+p=3.