Ware washing system containing cationic starch
View Patent ↗The present invention discloses a method of washing ware, in particular in an automatic domestic or institutional ware washing machine, using a detergent composition containing a cationic starch. This eliminates the need for a surfactant in the rinse step. The cationic starch provides a layer of cationic starch on the ware so as to afford a sheeting action in an aqueous rinse step without any added rinse agent.
1. A method of washing ware comprising:
(a) contacting ware in a washing step with an aqueous cleaning composition in a ware washing machine, the aqueous cleaning composition comprising a major portion of an aqueous diluent and about 200 to 5000 parts by weight of a ware washing detergent per each one million parts of the aqueous diluent, wherein the ware washing detergent comprises a nonionic surfactant; and
(b) contacting the washed ware in a rinse step with an aqueous rinse, the aqueous rinse being substantially free of an intentionally added rinse agent, characterized in that the aqueous cleaning composition contains a sufficient amount of a cationic starch to provide a layer of the cationic starch on the ware so as to afford sheeting action in the aqueous rinse step,
wherein a weight ratio of the nonionic surfactant to the cationic starch in the aqueous cleaning composition is at most 0.25/1,
further wherein the cationic starch contains a cationic group which is a quaternary ammonium group according to the formula
wherein R1, R2, R3 and R4 each independently are a alkyl or a hydroxyalkyl group and further wherein the cationic group is connected to the starch via an ether or an ester linkage, and
further wherein the cationic starch is (3-Chloro-2-Hydroxypropyl)Trimethylammonium Chloride modified starch.
2. The method according to claim 1 , wherein the cationic starch is contained in the detergent, and further wherein the cationic starch constitutes 0.01% to 50% (w/w) of the detergent.
3. The method according to claim 1 , wherein the cationic starch is present in the aqueous cleaning composition in an amount of 1 to 100 ppm.
4. The method according to claim 1 , wherein the ware washing machine is an automatic domestic machine.
5. The method according to claim 1 , wherein the ware washing machine is an automatic institutional machine.
6. The method according to claim 1 , wherein the washing
step comprises dosing of the detergent in a concentrated version and its dilution with the aqueous diluent.
7. The method according to claim 1 , wherein the detergent and the cationic starch are dosed as separate products into the washing step.
8. The method according to claim 1 , wherein the ware washing detergent is in the form of a powder, a tablet, or combinations thereof.
9. The method according to claim 1 , wherein the ware washing detergent is in a liquid or gel form.
10. The method according to claim 1 , wherein the cationic starch is contained in the detergent and further wherein the weight ratio of the nonionic surfactant to the cationic starch in the detergent is at most 0.25/1.
11. The method according to claim 2 , wherein the cationic starch constitutes 0.5% to 5% (w/w) of the detergent.
12. The method according to claim 3 , wherein the cationic starch is present in the aqueous cleaning composition in an amount of 2 to 50 ppm.
13. The method according to claim 10 , wherein the cationic starch constitutes 0.01% to 50% (w/w) of the detergent.
14. A method of washing ware comprising:
(a) contacting ware in a washing step with an aqueous cleaning composition in a ware washing machine, the aqueous cleaning composition comprising a major portion of an aqueous diluent and about 200 to 5000 parts by weight of a ware washing detergent per each one million parts of the aqueous diluent, wherein the ware washing detergent comprises a nonionic surfactant; and
(b) contacting the washed ware in a rinse step with an aqueous rinse, the aqueous rinse being substantially free of an intentionally added rinse agent, characterized in that the ware washing detergent further comprises a sufficient amount of a cationic starch to provide a layer of the cationic starch on the ware so as to afford sheeting action in the aqueous rinse step,
wherein a weight ratio of the nonionic surfactant to the cationic starch in the ware washing detergent is at most 0.25/1,
and further wherein the cationic starch provides a drying coefficient corresponding to a ratio of a drying time using the ware washing detergent with the cationic starch to a drying time using the ware washing detergent without the cationic starch being at most 0.9, and/or corresponding to a ratio of a number of droplets after 5 minutes using the ware washing detergent with the cationic starch to a number of droplets after 5 minutes using the ware washing detergent without the cationic starch being at most 0.5.
15. The method according to claim 14 , wherein the cationic starch constitutes 0.01% to 50% (w/w) of the detergent.
16. The method according to claim 14 , wherein the cationic starch is present in the aqueous cleaning composition in an amount of 1 to 100 ppm.
17. The method according to claim 14 , wherein the cationic starch is (3-Chloro-2-Hydroxypropyl)Trimethylammonium Chloride modified starch.
18. A method of washing ware comprising:
(a) contacting ware in a washing step with an aqueous cleaning composition in a ware washing machine, the aqueous cleaning composition comprising a major portion of an aqueous diluent and about 200 to 5000 parts by weight of a ware washing detergent per each one million parts of the aqueous diluent; and
(b) contacting the washed ware in a rinse step with an aqueous rinse, the aqueous rinse being substantially free of an intentionally added rinse agent, characterized in that the aqueous cleaning composition contains a sufficient amount of a cationic starch to provide a layer of the cationic starch on the ware so as to afford sheeting action in the aqueous rinse step,
wherein the aqueous cleaning composition does not contain a nonionic surfactant.
19. The method according to claim 18 , wherein the cationic starch is contained in the detergent.
20. The method according to claim 18 , wherein the cationic starch is present in the aqueous cleaning composition in an amount of 1 to 100 ppm.
21. The method according to claim 18 , wherein the cationic starch is (3-Chloro-2-Hydroxypropyl)Trimethylammonium Chloride modified starch.
22. The method according to claim 19 , wherein the cationic starch constitutes 0.01% to 50% (w/w) of the detergent.
23. The method according to claim 19 , wherein the cationic starch is (3-Chloro-2-Hydroxypropyl)Trimethylammonium Chloride modified starch.