Stable solid block metal protecting warewashing detergent composition

• US 6,410,495 B1
• Filed: 10/19/2000
• Issued: 06/25/2002
• Est. Priority Date: 01/13/1997
• Status: Expired due to Term

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: Ecolab, Inc.
• Inventors: Man, Victor F., Olson, Keith E., Lentsch, Steven E.
• Primary Examiner(s): Douyon, Lorna M.
• Application Number:
  US09/692,122
• Time in Patent Office: 614 Days
• Field of Search: 510/451, 510/224, 510/233, 510/445, 510/469, 510/509, 510/510, 510/511, 510/512, 134/25.2
• US Class Current: 510/224
• CPC Class Codes: C11D 17/0047 Detergents in the form of bars or tablets
• CPC Class Codes: C11D 17/0052 Cast detergent compositions
• CPC Class Codes: C11D 17/0065 Solid detergents containing builders C11D17/06 takes precedence
• CPC Class Codes: C11D 3/06 Phosphates, including polyphosphates
• CPC Class Codes: C11D 3/08 Silicates
• CPC Class Codes: C11D 3/10 Carbonates ; Bicarbonates
• CPC Class Codes: C11D 3/361 Phosphonates, phosphinates or phosphonites
• CPC Class Codes: C11D 3/364 containing nitrogen
• CPC Class Codes: C11D 7/12 Carbonates bicarbonates
• CPC Class Codes: C11D 7/36 containing phosphorus

Abstract

The dimensionally stable alkaline solid block warewashing detergent uses an E-form binder forming a solid comprising a sodium carbonate source of alkalinity, a metal corrosion protecting alkali metal silicate composition, a sequestrant, a surfactant package and other optional material. The solid block is dimensionally stable and highly effective in removing soil from the surfaces of dishware in the institutional and industrial environment. The E-form hydrate comprises an organic phosphonate and a hydrated carbonate.

Claims

1. A continuous extruded or cast solid detergent composition comprising:

a solidified mixture comprising;

(a) about 10 to 80 wt % of Na₂CO₃;

(b) an alkali metal silicate having a M₂O;

SiO₂ ratio of about 1;

1 to 1;

5; and

(c) an effective amount of an organic phosphonate hardness sequestering agent comprising a potassium salt;

 

wherein the mixture hardens to a solid form within about 1 minute to about 20 minutes, and the composition comprises about 5 to 20 wt % anhydrous sodium carbonate and binding agent comprising sufficient amounts of hydrated sodium carbonate and phosphonate comprising a potassium salt, to form the composition, and the composition provides metal protection and comprises either no second source of alkalinity or less than a solidification interfering amount of a second source of alkalinity.

2. The composition of claim 1, wherein the alkali metal silicate has a water content of about 5 to 25 wt %.

3. The composition of claim 1, wherein the composition comprises about 0.1 to less than about 2.0 moles of water per mole of sodium carbonate.

4. The composition of claim 1, wherein there are less than about 1.7 moles of water per mole of sodium carbonate.

5. The composition of claim 1, wherein the hydrated sodium carbonate comprises a monohydrate and the detergent comprises about 1.5 to 15 wt % of a surfactant composition comprising an anionic surfactant, a nonionic polymeric surfactant or mixtures thereof.

6. The composition of claim 1, wherein the composition is extruded to form a solid detergent composition.

7. The composition of claim 6, wherein the solid is provided in the form of a solid block.

8. The composition of claim 7, wherein the solid block has a mass of about 10 gms or greater.

9. The composition of claim 1, wherein the solid is provided in the form of a solid pellet.

10. The composition of claim 1, wherein the organic phosphonate sequestrant comprises a potassium phosphonate present in an amount of about 0.5 to 20 wt % of the mixture.

11. The composition of claim 10, wherein the composition also comprises an inorganic condensed phosphate.

12. The composition of claim 11, wherein the composition comprises about 3 to 20 wt % of the organic phosphonate and additionally comprises a tripolyphosphate sequestrant.

13. The composition of claim 1, wherein the composition is substantially free of NaOH.

14. The composition of claim 1, wherein the silicate comprises Na₂O:

SiO₂ in a ratio of about 1;

1.5 to 1;

2.5.

15. The composition of claim 1, wherein the composition comprises about 10 to 30 wt % of the alkali metal silicate.

16. The composition of claim 1, wherein the composition is cast to form a solid detergent composition.

17. A method of cleaning ware with a metal protecting anticorrosion alkaline detergent, the method comprising:

(a) providing a solid composition by solidifying a mixture which hardens to a solid form within about 1 minute to about 20 minutes, the mixture comprising about 20 to 60 wt % of Na₂CO₃;

about 10 to 30 wt % of an alkali metal silicate having an M₂O;

SiO₂ ratio of about 1;

1 to 1;

5; and

about 0.1 to 20 wt % of an organic phosphonate hardness sequestering agent comprising a potassium salt;

the solidified mixture comprising about 5 to 20 wt % anhydrous sodium carbonate and a binding agent comprising sufficient amounts of hydrated sodium carbonate and a potassium phosphonate to form the solid composition;

wherein the composition comprises either no second source of alkalinity or less than a solidification interfering amount of a second source of alkalinity, creating washed ware while protecting metal ware from corrosion;

(b) dissolving a portion of the solid composition in a solvent to form an alkaline detergent solution; and

(c) contacting ware with the alkaline detergent solution.

18. The method of claim 17, wherein the concentration of the solid composition in the alkaline detergent solution is in the range of about 100 parts to about 2500 parts of detergent per each one million parts by weight of the detergent solution.

19. The method of claim 18, wherein the alkali metal silicate has a water content of about 5 to 25 wt %.

20. The method of claim 18, wherein the alkali metal silicate has a M₂O:

SiO₂ of about 1;

1.5 to about 1;

2.5.

21. The method of claim 17, wherein the detergent comprises about 15 to about 30 wt % of the alkali metal silicate having an M₂O:

SiO₂ ratio of about 1;

2 and a water content of about 15 to 20 wt %.

22. The method of claim 17, wherein the solution is an aqueous solution.

23. The method of claim 17, wherein the solid composition is provided in the form of a solid block.

24. The method of claim 17, wherein the solid composition is provided in the form of a pellet.