Alkaline cleaning compositions
Alkaline cleaning compositions that are useful to remove burnt-on and/or baked-on soil deposits and grease are described. The alkaline cleaning compositions comprise a buffering system of a strong base and an organic acid such that the pH is maintained in the range of about 10 to about 11.2. Also described are methods of removing burnt-on or baked on soil deposits or grease.
1. A cleaning composition comprising:
(i) a buffering system comprising a strong base having a pKa of at least 13 and at least one acid selected from an organic acid, phosphonic acid, and phosphoric acid;
(ii) monoethanolamine;
(iii) a surfactant system comprising cocoamidopropyl betaine, a polyethoxylated alcohol, and sodium cumene sulfonate;
(iv) ethanol; and
(v) propylene glycol n-butyl ether,
wherein the pH of the composition is about 9 to about 13.
2. The cleaning composition of claim 1 , wherein the polyethoxylated alcohol comprises a C 9 -C 11 alkanol condensed with about 2.5 moles of ethylene oxide.
3. The cleaning composition of claim 1 , wherein the pH of the composition is about 10 to about 12.
4. The cleaning composition of claim 1 wherein the organic acid is chosen from citric acid, lactic acid, formic acid, oxalic acid, acetic acid, salicylic acid, or mixtures thereof.
5. The cleaning composition of claim 1 wherein the strong base is chosen from sodium hydroxide, potassium hydroxide, lithium hydroxide or mixtures thereof.
6. The cleaning composition of claim 1 wherein the polyethoxylated alcohol comprises at least one molecule of Formula 1:
CH 3 (CH 2 ) m —(O—CH 2 —CH 2 ) n —OH (I)
wherein m is 8 to 12 and n represents an average degree of ethoxylation for the mixture of about 1 to about 15.
7. The cleaning composition of claim 1 further comprising an anionic surfactant which is a sodium or ammonium lauryl ether sulfate with 1, 2 or 3 moles of ethylene oxide.
8. The cleaning composition of claim 1 further comprising an anionic sulfonate surfactant.
9. The cleaning composition of claim 1 further comprising a surfactant soluble carboxylated polyelectrolyte copolymer.
10. The cleaning composition of claim 1 wherein the strong base is present in an amount of about 0.01 to about 5% by weight of the cleaning composition.
11. The cleaning composition of claim 1 wherein the organic acid is present in an amount of about 0.01 to about 5% by weight of the cleaning composition.
12. The cleaning composition of claim 1 wherein the cocoamdiopropyl betaine is present in an amount by weight of about 1 to about 8% by weight of the cleaning composition.
13. A composition useful for removing baked-on or burnt on soils from a surface, the composition comprising:
(i) a buffering system comprising about 0.2 to about 1% by weight of the composition of sodium hydroxide and about 0.5 to about 2.5% by weight of the composition of citric acid;
(ii) about 0.01 to about 5% monoethanolamine;
(iii) about 1 to about 4.5% cocoamidopropyl betaine;
(iv) about 0.5 to about 1.5% of a surfactant soluble carboxylated polyelectrolyte copolymer;
(v) about 1 to about 3% ethanol; and
(vi) about 2 to about 4% propylene glycol n-butyl ether;
wherein the pH of the composition is about 9 to about 13.
14. A method of removing burnt-on or baked-on soil or grease from a surface comprising the step of applying the cleaning composition of claim 1 onto the surface.
15. The composition of claim 13 further comprising a C 9-11 alcohol with a degree of ethoxylation of about 2.5 and sodium cumene sulfonate.
16. A method of removing burnt-on or baked-on soil or grease from a surface comprising the step of applying the cleaning composition of claim 13 onto the surface.
17. A cleaning composition comprising:
(i) a buffering system comprising about 0.2 to about 1% by weight of the composition of sodium hydroxide and about 0.5 to about 2.5% by weight of the composition of citric acid;
(ii) an alkanolamine;
(iii) a surfactant system comprising a zwitterionic surfactant, a non-ionic surfactant, an anionic surfactant and mixtures thereof; and
(iv) an organic solvent system comprising a C 2 -C 5 alkanol and a glycol ether;
wherein the pH of the composition is about 9 to about 13.
18. The cleaning composition of claim 17 further comprising a surfactant soluble carboxylated polyelectrolyte copolymer.
19. The cleaning composition of claim 17 , wherein the organic solvent system comprises ethanol and propylene glycol n-butyl ether.
20. The cleaning composition of claim 17 , wherein the surfactant comprises cocoamidopropyl betaine, and a C 9 -C 11 alkanol condensed with about 2.5 moles of ethylene oxide, and sodium cumene sulfonate.
21. A method of removing burnt-on or baked-on soil or grease from a surface comprising the step of applying the cleaning composition of claim 17 onto the surface.