Stable solid block metal protecting warewashing detergent composition

• US 20040102353A1
• Filed: 11/14/2003
• Published: 05/27/2004
• Est. Priority Date: 01/13/1997
• Status: Active Grant

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: Ecolab, Inc.
• Inventors: Man, Victor F., Olson, Keith E., Lentsch, Steven E.
• Granted Patent: US 7,087,569 B2
• Time in Patent Office: Days
• US Class Current: 510/445
• 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 solid block warewashing detergent composition 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;

wherein the block comprises non-hydrated sodium carbonate and a binding agent comprising hydrated sodium carbonate and organic phosphonate, and wherein the block is substantially free of a second source of alkalinity.

2. The method 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 block comprises about 0.1 to 2.0 moles of water per mole of sodium carbonate

4. 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.

5. The block of claim 1 wherein the blended mass is extruded to form the block.

6. The composition of claim 1 wherein the block has a mass greater than about 10 gms.

7. The block of claim 1 wherein the organic phosphonate sequestrant comprises a potassium phosphonate and is used in an amount of about 0.5 to 20 wt %.

8. The block of claim 7 wherein the sequestrant also comprises an inorganic condensed phosphate.

9. The block of claim 8 wherein the sequestrant comprises about 3 to 20 wt % of the organic phosphonate and additionally comprises a tripolyphosphate sequestrant.

10. The block of claim 1 wherein there are less than about 1.7 moles of water per mole of sodium carbonate.

11. The block of claim 1 wherein the solid product is substantially free of NaOH.

12. The block of claim 1 wherein the silicate comprises Na₂O:

SiO₂ of about 1;

1.5 to 1;

2.5.

13. The block of claim 1 wherein the block comprises about 10 to 30 wt % of the alkali metal silicate.

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

(a) contacting ware with an alkaline solid block warewashing detergent comprising about 20 to 60 wt % of Na₂CO₃;

about 10 to 30 wto/o 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;

the block comprising nonhydrated sodium carbonate and a binding agent comprising hydrated sodium carbonate and an organic phosphonate;

wherein the block is substantially free of a second source of alkalinity, creating washed ware; and

(b) rinsing the washed ware.

15. The method of claim 14 wherein the concentration of the detergent in the aqueous alkaline detergent comprises about 100 parts of detergent to about 2500 parts of detergent per each one million parts by weight of the aqueous detergent.

16. The method of claim 15 wherein the alkali metal silicate has a water content of about 5 to 25 wt %.

17. The method of claim 15 wherein the alkali metal silicate has a M₂O:

SiO₂ of about 1;

1.5 to about 1;

2.5.

18. The method of claim 14 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 %.