WO1995014077B1

WO1995014077B1 - Bleach activator compositions

Info

Publication number: WO1995014077B1
Application number: PCT/GB1994/002520
Authority: WO
Filing date: 1994-11-16
Publication date: 1995-06-15

Abstract

A process for making a coated bleach component which may be incorporated into a detergent composition comprising hydrogen peroxide solution. The process includes the steps of dispersing the bleach component in a continuous liquid phase to form discrete islands of dispersed phase and subsequently forming a polymeric coating at the interface between the dispersed phase and the continuous phase. The coating formed is resistant to hydrogen peroxide solution and is removable when the liquid continuous phase is diluted with aqueous wash liquor. In this way particulate material which reacts with hydrogen peroxide can be incorporated into an aqueous detergent liquid which contains dissolved hydrogen peroxide, whilst maintaining stability.

Claims

AMENDED CLAIMS[received by the International Bureau on 15 May 1995 (15.05.95); original claim 1 amended; new claims 7 and 12 added; original claims 7-10 amended and renumbered 8-11; remaining claims unchanged (2 pages)]

1. A process for making a coated peroxygen bleach component including the steps of dispersing the bleach component in a continuous liquid phase to form discrete islands of dispersed phase and then forming a polymeric coating at the interface between the dispersed phase and the continuous phase, the coating being resistant to hydrogen peroxide solution and being removable when the liquid continuous phase is diluted with aqueous wash liquor.

2. A process according to claim 1 in which the polymer is formed by azeotroping, coacervation or in situ polymerisation.

3. A process according to claim 2 in which the polymer coating is formed from a mixture of neutralised polyacrylates containing a propionic acid repeating unit:

R

*= ^{' CH}2*r, co₂x^* where X is Na, K, NH₄NH₂CH₂CH₂ or H; R is CH₃ or preferably H: and n is chosen to give a maximum molecular weight of 100000 and a polyamide: f H - CH₂}„

CONH₂ where m is chosen to give a large molecular weight backbone > 300000.

4. A method according to claim 3 in which the polymer coating further includes a crosslinker.

5. A process according to claim 4 in which the crosslinker is selected from urea, melamine, formaldehyde and urea formaldehyde or melamine formaldehyde resins.

6. A process according to claim 4 in which the crosslinker is polyvinyl pyrrolidine.

7. A process according to any preceding claim in which the peroxygen bleach component is selected from peroxygen bleach precursors, preferably inorganic persalts, and peroxygen bleach activators, preferably N- and O-acyl activator components.

8. A process according to claim 7 in which the bleach activator is tetra acetyl ethylene diamine (TAED) .

9. An aqueous detergent liquid including water, surfactant and dissolved hydrogen peroxide characterised in that the detergent liquid also includes a particulate material which reacts with hydrogen peroxide and the material is coated using a method including the steps of dispersing the particulate material in a continuous liquid phase to form discrete islands of dispersed phase and then forming a polymeric coating at the interface between the dispersed phase and the continuous phase, the coating being resistant to hydrogen peroxide solution and being removable when the liquid continuous phase is diluted with aqueous wash liquor.

10. A detergent liquid according to claim 9 in which the material is a solid.

11. A detergent liquid according to claim 9 or 10 in which the material is a peroxygen bleach component, preferably a peroxygen bleach activator, more preferably TAED.

12. A liquid according to any of claims 9 to 11 in which the coating method has any of the further features defined in claims 2 to 6.

AMENDED SHEET ARTICLE -9