Method for treating laundry
A method for treating laundry is provided. The method includes steps of applying a bleaching and antimicrobial composition to laundry in a laundry washing machine at a first pH that favors bleaching properties and at a second pH that favors antimicrobial properties, wherein the first pH and the second pH are different, and draining the bleaching and antimicrobial composition from the laundry. The step of applying a bleaching and antimicrobial composition to laundry can include a step of washing the laundry with a detergent composition for the removal of soil. In addition, the step of applying a bleaching and antimicrobial composition to laundry can precede or follow a step of washing laundry with a detergent composition for the removal of soil. A bleaching and antimicrobial composition and a laundry washing machine are provided.
1. A method for treating laundry, the method comprising:
(a) washing the laundry with a detergent use solution at an alkaline pH in an industrial laundry washing machine for removal of soil from the laundry; and thereafter draining at least a portion of the detergent use solution from the laundry washing machine; and thereafter
(b) applying a laundry treatment composition comprising a bleaching/antimicrobial agent selected from the group consisting of a halogen bleach, an oxygen bleach, and mixtures thereof, to the laundry in an industrial laundry washing machine at a pH from about 2 to about 4 for about 3 minutes to about 10 minutes, and thereafter at a pH from about 8 to about 11 for about 3 minutes to about 10 minutes; wherein a pH adjusting agent is added to increase the pH; and
(c) draining the laundry treatment composition from the laundry.
2. A method according to claim 1 , wherein the laundry treatment composition further comprises a detergent composition for removal of soil from the laundry.
3. A method according to claim 1 , wherein the pH adjusting agent comprises at least one of alkaline metal hydroxide, alkaline metal silicate, alkaline metal carbonate, alkaline metal bicarbonate, alkaline metal sesquicarbonate, and alkaline metal borate.
4. A method according to claim 1 , wherein the laundry treatment composition comprises a coated pH adjusting agent that introduces the pH adjusting agent once the coating has degraded.
5. A method according to claim 1 , wherein the halogen bleach comprises at least one of chlorine dioxide, potassium dichloroisocyanurate, sodium dichloroisocyanurate, chlorinated trisodiumphosphate, sodium hypochlorite, calcium hypochlorite, lithium hypochlorite, monochloramine, dichloroamine, [(monotrichloro)-tetra (monopotassium dichloro)]pentaisocyanurate, paratoluene sulfondichloro-amide, trichloromelamine, N-chlorammeline, N-chlorosuccinimide, N,N′-dichloroazodicarbonamide, N-chloro-acetyl-urea, N,N′-dichlorobiuret, chlorinated dicyandiamide, trichlorocyanuric acid, dichloroglycoluril, 1,3-dichloro-5,5-dimethyl hydantoin, 1-3-dichloro-5-ethyl-5-methyl hydantoin, 1-choro-3-bromo-5-ethyl-5-methyl hydantoin, dichlorohydantoin, salts or hydrates thereof, and mixtures thereof.
6. A method according to claim 1 , wherein the oxygen bleach comprises an inorganic active oxygen composition comprising at least one of hydrogen peroxide, hydrogen peroxide adduct, ozone, group IIIA active oxygen compound, group VIA active oxygen compound, group VA active oxygen compound, group VIIA active oxygen compound, and mixtures thereof.
7. A method according to claim 1 , wherein the oxygen bleach comprises at least one of a peroxycarboxylic acid, an ester of peroxycarboxylic acid, an alkaline metal salt of a peroxycarboxylic acid, and adducts thereof.
8. A method according to claim 1 , wherein the oxygen bleach comprises at least one of C 1 -C 10 aliphatic peroxycarboxylic acid, salt of C 1 -C 10 aliphatic peroxycarboxylic acid, ester of C 1 -C 10 aliphatic peroxycarboxylic acid, and mixture thereof.
9. A method according to claim 1 , wherein the oxygen bleach comprises peroxyoctanoic acid.
10. A method according to claim 1 , wherein the laundry treatment composition further comprises an activator.
11. A method according to claim 1 , wherein the laundry treatment composition further comprises at least one of souring agents, fabric softening agents, starch, sizing agents, color-fastness agents, oil and water repellant agents, water conditioning agents, iron controlling agents, water threshold agents, soil releasing agents, soil shielding agents, optical brightening agents, fragrances, and mixtures thereof.
12. A method according to claim 1 , further comprising a step of rinsing the laundry treatment composition from the laundry.