Preparations, their production and use
A composition for machine dishwashing that includes a one copolymer obtainable by copolymerization of N-vinylamide, vinyl acetate, polyether, and alkoxylate.
1. A method of washing dishes in a machine dishwasher, the method comprising
providing to the machine dishwasher a composition comprising
(a1) a copolymer obtainable by copolymerization of
(a1.1) a N-vinylamide,
(a1.2) vinyl acetate,
(a1.3) a polyether,
(a1.4) optionally a further comonomer,
(a2) an ethoxylate of a linear C 16 -C 18 -alkanol having on average 8.5 to 9.5 mol of ethylene oxide per mole of linear C 16 -C 18 -alkanol; or an alkoxylate comprising at least 80% by weight of at least one ethoxylate of a linear C 16 -C 18 -alcohol of formula (I) where m is 8, 9 or 10,
R 1 —(OCH 2 CHR 2 ) m R 3 (I)
where:
R 1 is a C 16 -C 18 linear alkyl,
R 2 is C 1 -C 10 -alkyl, in each case identical or different, linear or branched, or hydrogen, and
R 3 is C 1 -C 4 -alkyl, linear or branched.
2. The method according to claim 1 , wherein the composition comprises from 1 to 50% by weight of the copolymer (a1) and 50 to 99% by weight of (a2).
3. The method according to claim 1 , wherein the copolymer (a1) is obtainable by copolymerization of
from 30 to 80% by weight of N-vinylamide (a1.1),
from 10 to 50% by weight of vinyl acetate (a1.2),
from 10 to 50% by weight of polyether (a1.3),
from zero to 10% by weight of comonomer(s) (a1.4),
in each case based on the mass of the total copolymer (a1).
4. The method according to claim 1 , wherein copolymer (a1) is a graft copolymer.
5. The method according to claim 1 , wherein the N-vinylamide (a1.1) is a N-vinyllactam.
6. The method according to claim 1 , wherein the N-vinylamide (a1.1) is N-vinylpyrrolidone or N-vinylcaprolactam.
7. The method according to claim 1 , wherein the polyether (a1.3) is a polyethylene glycol having an average molecular weight M w of from 1000 to 100 000 g/mol.
8. The method according to claim 1 , wherein (a.2) is an ethoxylate of a linear C 16 -C 18 -alkanol having on average 8.5 to 9.5 mol of ethylene oxide per mole of linear C 16 -C 18 -alkanol.
9. The method according to claim 1 , wherein (a2) comprises at least 80% by weight of at least one ethoxylate of a linear C 16 -C 18 -alcohol of the formula (I) where m is 8, 9 or 10.
10. The method according to claim 1 , wherein the copolymer (a1) and the alkoxylate (a2) are present as a solid solution.