Method of laundering fabric

Patent metadata

Field	Value
Publication number	US-12398345-B2
Application number	US-202217714173-A
Country	US
Kind code	B2
Filing date	Apr 6, 2022
Priority date	Oct 8, 2019
Publication date	Aug 26, 2025
Grant date	Aug 26, 2025

Abstract

A method of laundering fabric, where the method includes the steps of:
(a) in a main washing step, washing soiled fabric with an aqueous wash bath including detersive surfactant and one or more of the following components: perfume, brighteners, hueing dyes, enzymes, or any combination thereof; and (b) in a rinsing step, rinsing the soiled fabric with an aqueous rinsing solution including photo-bleach;

where an artificial light source is present and turned on during at least part of the rinsing step (b) and provides light to the aqueous rinsing solution in such a manner that activates the photo-bleach present in the aqueous rinsing solution, and where the artificial light source is turned off during at least part of the main washing step (a) and does not provide any light to the aqueous wash bath.

First claim

The invention claimed is:

1. A method of laundering fabric, wherein the method comprises the steps of:
(a) in a main washing step, washing soiled fabric with an aqueous wash bath comprising detersive surfactant enzymes and optionally one or more of the following components: perfume, brighteners, hueing dyes, or any combination thereof; and
(b) in a rinsing step, rinsing the soiled fabric with an aqueous rinsing solution comprising photo-bleach;
wherein an artificial light source is present and turned on during the rinsing step (b) and provides light to the aqueous rinsing solution in such a manner that activates the photo-bleach present in the aqueous rinsing solution,
and wherein the artificial light source is turned off during the main washing step (a) and does not provide any light to the aqueous wash bath.

2. A method according to claim 1 , wherein the method is carried out in an automatic washing machine, and the artificial light source is a light bulb present in the washing drum of the automatic washing machine.

3. A method according to claim 1 , wherein the photo-bleach is selected from the group consisting of: riboflavin; phloxine B; erythrosine; salts of any of these photo-bleaches; derivatives of any of these photo-bleaches; and any combination thereof.

4. A method according to claim 1 , wherein:
(a) the photo-bleach is thioxanthone, and wherein the artificial light source provides light having a wavelength of from about 300 nm to about 400 nm;
(b) the photo-bleach is riboflavin, and wherein the artificial light source provides light having a wavelength of from about 400 nm to about 480 nm;
(c) the photo-bleach is phloxine B, and wherein the artificial light source provides light having a wavelength of from about 460 nm to about 570 nm;
(d) the photo-bleach is erythrosine, and wherein the artificial light source provides light having a wavelength of from about 460 nm to about 550 nm; and/or
(e) the photo-bleach is phthalocyanine derivative, and wherein the artificial light source provides light having a wavelength of from about 550 nm to about 750 nm.

5. A method according to claim 1 , wherein the aqueous wash bath comprises a hueing dye.

6. A method according to claim 1 , wherein the aqueous wash bath comprises a brightener.

7. A method according to claim 1 , wherein the aqueous rinsing solution further comprises a fabric softener.

8. A method according to claim 1 , wherein the artificial light source comprises two or more bulbs.

9. A method according to claim 1 , wherein the artificial light source emits diffused light.

Assignees

• Procter & Gamble

Inventors

• Amador Zamarreno Carlos
• Brooker Anju Deepali Massey
• Bueno Romo Laura
• Chieffi Andre
• Moon Andrew Philip

Classifications

• C11D2111/12

  Soft surfaces, e.g. textile · CPC title

• C11D2111/44

  Multi-step processes · CPC title

• D06L1/08

  Multi-step processes · CPC title

• C11D3/505

  encapsulated or adsorbed on a carrier, e.g. zeolite or clay · CPC title

• C11D3/42

  Brightening agents {; Blueing agents} · CPC title