Patent · US Expired

Bleaching with improved whitening

US7285522B2 · kind B2 · utility

11Cited by
20References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 25, 2004
Grant dateOct 23, 2007
Priority date
Expiry dateJan 28, 2025

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC11D3/42
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

The invention provides methods, compositions and kits for increasing the brightness retention of a fabric laundered using a hypohalite-generating bleach by employing an amount of bromide-releasing compound sufficient to provide between 0.1 to about 1.5 moles of bromine ion to mole of available chlorine in a wash liquor to mitigate the negative effects of said hypohalite bleach on the optical brightener present in either the wash liquor or on said fabric. The invention also applies to fabrics washed using commercial laundry detergents which typically deliver an optical brightener into said wash liquor, said optical brightener generally exhibiting instability in the presence of said hypohalite bleaches. By employing the inventive methods and/or use of the inventive compositions, enhanced protection of the optical brightener is enabled, resulting in increased brightening of the laundered fabrics, determined versus a control as an increase in the Stensby whiteness measure of the fabric by a ΔW value of greater than about 3.0.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.