Shaped solid bleach with encapsulate source of bleach

• US 5,407,598 A
• Filed: 02/26/1993
• Issued: 04/18/1995
• Est. Priority Date: 02/26/1993
• Status: Expired due to Term

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: Ecolab, Inc.
• Inventors: Man, Victor F., Olson, Keith E.
• Primary Examiner(s): Lovering, Richard D.
• Application Number:
  US08/023,941
• Time in Patent Office: 781 Days
• Field of Search: 252/186.25, 252/186.35, 252/90, 252/99, 252/174.13, 427/213.31, 428/402.24
• US Class Current: 252/186.35
• CPC Class Codes: C11D 17/0065 Solid detergents containing builders C11D17/06 takes precedence
• CPC Class Codes: C11D 3/3953 Inorganic bleaching agents C11D3/3951 takes precedence
• CPC Class Codes: C11D 3/3955 Organic bleaching agents C11D3/3951 takes precedence
• CPC Class Codes: Y10T 428/2989 Microcapsule with solid core [includes liposome]

Abstract

Aqueous bleach solutions can be made by directing a spray of water onto a bulk or shaped solid (brick, tablet, block, etc.) comprising a continuous solid phase of an encapsulated source of an active halogen bleach or a solid comprising a source of an oxidizing active halogen bleach and an encapsulated oxidizing halogen bleach source. Such shaped solids can be used to dispense uniform quantities of an aqueous bleach concentrate to bleaching locus such as a washing machine. The tablets can be made from the encapsulated bleach or from a powder mixture of a particulate, granulated or powdered unencapsulated source of active oxidizing bleach and an encapsulated source of active oxidizing bleach by forming the powder mixture into a desired shape. The presence of the encapsulate in the solid with the powder reduces the tendency of the solid to absorb water which can be wicked through the solid to pass water through the solid into adjacent solids. Substantial proportions of absorbed water can cause the tablets to crack, crumble and to periodically dispense uneven, substantially large and undesirable concentrations of active bleach into a wash or bleach cycle.

Claims

1. A shaped solid halogen bleach composition comprising a continuous solid phase of an active halogen bleach source and about 10 to 80 wt %, based on the solid, of an encapsulate active halogen bleach source, said encapsulate comprising an active halogen source and at least one encapsulating layer.

2. The solid of claim 1 wherein the shaped solid is a cylindrical solid with a thickness of about 10 to 80 millimeters and a diameter of about 20 to 150 millimeters, wherein the encapsulate is evenly dispersed throughout the solid phase.

3. The solid of claim 2 wherein the source of active halogen of the continuous phase or the halogen source of the encapsulate comprises a chlorinated isocyanuric acid compound.

4. The solid of claim 1 wherein the mass of the solid is at least 1 gram and the encapsulate has a diameter no greater than about 5 millimeters.

5. The solid of claim 1 wherein the active halogen bleach comprises a source of active chlorine.

6. The solid of claim 5 wherein the source of active chlorine comprises chlorinated trisodium phosphate, chlorinated sodium tripolyphosphate, or mixtures thereof.

7. The solid of claim 1 wherein the encapsulate comprises a core of an active halogen source and at least one organic encapsulating layer.

8. The solid of claim 1 wherein the encapsulate comprises a core comprising an active halogen source and at least one inorganic encapsulating layer.

9. The solid of claim 1 wherein the encapsulate comprises a core of an active halogen source, a first inorganic inner layer and a second organic outer layer.

10. The solid of claim 1 wherein the continuous solid phase also contains a binder (tableting aid).

11. The solid of claim 1 wherein the solid comprises a compressed solid.

12. The solid of claim 1 wherein the particle size of the continuous phase is about 0.2 to 5 millimeters.

13. The solid of claim 1 wherein the solid further comprises a wetting agent.

14. The solid of claim 1 wherein the solid further comprises a sequestrant.

27. A method of washing laundry with an aqueous bleach, said method comprising contacting a wash load with an aqueous bleach solution made by contacting the bleach solid of claim 1 with an aqueous spray.

15. A solid tablet chlorine bleach composition comprising a continuous solid phase of an active chlorine source and about 10 to 80 wt % based on the solid of an encapsulated chlorinated isocyanuric acid, said encapsulate comprising an active core of chlorinated isocyanuric acid and at least one encapsulating layer.

16. The solid of claim 15 wherein the chlorine source of the continuous solid phase also comprises chlorinated isocyanuric acid.

17. The solid of claim 15 wherein the solid phase comprises chlorinated trisodium phosphate, chlorinated trisodium polyphosphate, calcium hypochlorite or mixtures thereof.

18. The solid of claim 15 wherein the thickness of the solid is about 20 to 80 millimeters having a diameter of about 50 to 150 millimeters and the encapsulated chlorinated isocyanurate is evenly dispersed throughout the solid phase.

19. The solid of claim 18 having a mass of at least 1 gram and a particulate having a diameter of no greater than about 5 millimeters.

20. The solid of claim 18 wherein the encapsulate has at least one inorganic layer.

21. The solid of claim 18 wherein the encapsulate has at least one organic layer.

22. The solid of claim 18 wherein the encapsulate comprises a core of chlorinated isocyanuric acid, a first inner inorganic layer and an external organic layer.

23. The solid of claim 18 wherein the solid phase further contains a diluent.

24. The solid of claim 18 wherein the continuous phase further contains a binder (tableting aid).

25. The solid of claim 18 wherein the continuous phase further comprises a wetting agent.

26. The solid of claim 18 wherein the continuous phase further comprises a sequestrant.

28. A method of washing laundry with an aqueous bleach, said method comprising contacting a wash load with an aqueous bleach solution made by contacting the bleach solid of claim 18 with an aqueous spray.