Use of polyaralkylamines as corrosion inhibitors

Claim 1

In the method of protecting metals from corrosion wherein an effective amount of a corrosion inhibiting agent is added to the liquid medium with which said metals are in contact, the improvement which comprises using as the corrosion inhibiting agent a polyaralkylamine of the formula ##STR20## wherein R 1 to R 4 are identical or different and are hydrogen, C 1 -C 18 -alkyl, benzyl, α-methylbenzyl, α,α-dimethylbenzyl, 4-methylbenzyl and tert.-butylbenzyl, or polybenzyl, poly α-methylbenzyl, poly α, α-dimethylbenzyl, poly 4-methylbenzyl and poly tert.-butyl benzyl or C 6 -C 15 -aryl, or R 1 to R 4 are linked to one another in such manner that in each case two of the radicals, together with the nitrogen atom linking them or together with the N-C-containing remainder of the chain, form a 5-membered to 6-membered ring, at least one of the radicals R 1 to R 4 denoting benzyl, α-methylbenzyl, α,α-dimethylbenzyl, 4-methylbenzyl and tert.-butylbenzyl, or polybenzyl, poly α-methylbenzyl, poly α,α-dimethylbenzyl, poly 4-methylbenzyl and poly tert.-butyl benzyl, and R 5 and R 6 independently of one another are hydrogen, C 1 -C 6 -alkyl, C 5 -C 7 -cycloalkyl, C 7 -C 12 -aralkyl or C 6 -C 10 -aryl, m is an integer from 2 to 10, and n is an integer from 2 to 30, and the C-chain defined by m can contain different radicals R 5 and R 6 and the C-N chain defined by n can have different values of m.