Composition and method
A low-foaming composition for cleaning a ware-washing machine comprises water, an alkoxylate, an acid (preferably citric acid), and preferably a phase separation promoter (for example a polyethylene glycol or an ionic salt). The composition is in two separate layers under ambient conditions.
1. A method of cleaning a ware-washing machine, comprising:
supplying a liquid machine-cleaner composition to the ware-washing machine; and
running a wash cycle of the machine at 50° C. or above, without wares in the machine;
wherein the liquid machine-cleaner composition comprises water, an alkoxylate, a stabilizer and an acid,
wherein the alkoxylate is an alcohol ethoxylate having an average 6-20 carbon atoms in the “body” and an average 2-14 moles of ethylene oxide in the “tail”, per mole of the alcohol,
wherein the liquid machine-cleaner composition comprises two separate liquid layers under ambient conditions; and
wherein the liquid machine-cleaner composition does not contain any anionic surface active agents.
2. The method according to claim 1 , wherein the liquid machine-cleaner composition is in two separate layers throughout the range from 0° C.-50° C. when at a pressure of 1.01×10 5 Pa.
3. The method according to claim 1 , wherein the liquid machine-cleaner composition further comprises a phase separation promoter.
4. The method according to claim 3 , wherein the liquid machine-cleaner composition comprises 0.01 to 25 wt % of the phase separation promoter.
5. The method according to claim 3 , wherein the phase separation promoter is selected from one or more of a polyethylene glycol and a soluble ionic salt.
6. The method according to claim 3 , wherein the phase separation promoter is a polyethylene glycol in the range from PEG 2000 to PEG 10000.
7. The method according to claim 1 , wherein the acid is present in an amount from 1 to 30 wt %.
8. The method according to claim 1 , wherein the acid is an organic acid.
9. The method according to claim 8 , wherein the organic acid is a carboxylic acid.
10. The method according to claim 9 , wherein the carboxylic acid is citric acid.
11. The method according to claim 1 , wherein the alkoxylate is present in an amount from 1 to 20 wt %.
12. The method according to claim 1 , wherein the alkoxylate has an HLB value in the range 6 to 15.
13. The method according to claim 1 , wherein the alcohol ethoxylate has an average 7-15 carbon atoms in the “body” and an average 2-6 moles ethylene oxide in the “tail”, per mole of the alcohol.
14. The method according to claim 1 , wherein the liquid machine-cleaner composition is substantially free from hydrophobic compounds.
15. The method according to claim 1 , wherein the liquid machine-cleaner composition consists essentially of:
the alkoxylate;
an acid;
water;
and optionally, an auxiliary.
16. The method according to claim 1 , wherein the liquid machine-cleaner composition consists essentially of:
the alkoxylate;
an acid;
water;
a phase separation promoter;
and optionally, an auxiliary.
17. The method according to claim 1 , wherein the liquid machine-cleaner composition is supplied to the machine from a single-shot machine-cleaner container.
18. The method according to claim 17 , wherein the layers of the liquid machine-cleaner composition are visually distinct and may be seen through the wall(s) of the single-shot machine-cleaner container.
19. The method according to claim 17 , wherein the single-shot machine-cleaner container is sealed by a closure which is not removed before use, but which instead is breached in use in the machine, the closure being solid under ambient conditions but soluble or dispersible in water at an elevated temperature.