Thickened aqueous prewash composition

Claim 1

An aqueous laundry prewash composition for treating fabric spots, stains and the like, comprising a cosurfactant system including a first hydrophobic nonionic surfactant for loosening oil soluble material from the fabric and a second hydrophilic nonionic surfactant for loosening water soluble material from the fabric, the hydrophobic nonionic surfactant being an oil soluble ethoxylated alcohol with about eight to eighteen carbon atoms and an average of about two to five ethylene oxide groups per molecule, the hydrophilic nonionic surfactant being a water soluble ethoxylated alcohol with about eight to eighteen carbon atoms and an average of about five to fifteen ethylene oxide groups per molecule, the cosurfactant system forming about 3.7-10.5 weight percent of the composition, a hydrotrope selected for stabilizing the cosurfactant system and particularly the first hydrophobic nonionic surfactant in the prewash composition, the hydrotrope being a benzene or naphthalene sulfonate derivative containing one or more short chain alkyl substituents with about one to four carbon atoms, the hydrotrope forming about 1.6-10.0 weight percent of the composition, Xanthan gum as a thickener for maintaining viscosity of the composition in a thickened condition and for achieving localized engagement of the composition on the fabric spots and stains, the thickener forming about 0.1-2 percent by weight of the composition, and water forming the balance of the compositions as a predominant component thereof, the hydrotrope being present in the composition in a ratio of at about three parts for each part of the first hydrophobic nonionic surfactant in order to assure stability of the thickened prewash composition.

Claim 9

A method for removing localized soil from a fabric, comprising contacting the localized fabric soil with a prewash composition including a cosurfactant system including a first hydrophobic nonionic surfactant for loosening oil soluble material from the fabric and a second hydrophilic nonionic surfactant for loosening water soluble material from the fabric, the first hydrophobic nonionic surfactant being an oil soluble ethoxylated alcohol with about eight to eighteen carbon atoms and an average of about two to five ethylene oxide groups per molecule, the second hydrophilic nonionic surfactant being a water soluble ethoxylated alcohol with about eight to eighteen carbon atoms and an average of about five to fifteen ethylene oxide groups per molecule, the cosurfactant system forming about 3.7-10.5 weight percent of the prewash composition, a hydrotrope selected from the class consisting of benzene and naphthalene sulfonate derivatives containing one or more short chain alkyl substituents having about one to four carbon atoms for stabilizing the cosurfactant system and particularly the first hydrophobic nonionic surfactant in the prewash composition, a thickener selected from the class consisting of xanthan gum, polyacrylic acid and polystyrene sulfonate for maintaining viscosity of the composition in a thickened condition in order to maintain the composition in localized engagement on the fabric spots and stains, the thickener forming about 0.1-2 percent by weight of the prewash composition, and water forming the balance of the composition as a predominant component thereof, the hydrotrope being present in the composition in a ratio of at least three parts for each part of the first hydrophobic nonionic surfactant in order to assure stability of the thickened prewash composition.

Claim 10

A method for removing localized soil from a fabric, comprising contacting the localized fabric soil with a prewash composition including a cosurfactant system including a first hydrophobic nonionic surfactant for loosening oil soluble material from the fabric and a second hydrophilic nonionic surfactant for loosening water soluble material from the fabric, the first hydrophobic nonionic surfactant being an oil soluble ethoxylated alcohol with about eight to eighteen carbon atoms and an average of about two to five ethylene oxide groups per molecule, the second hydrophilic nonionic surfactant being a water soluble ethoxylated alcohol with about eight to eighteen carbon atoms and an average of about five to fifteen ethylene oxide groups per molecule, the cosurfactant system forming about 3.7-10.5 weight percent of the prewash composition, a hydrotrope selected from the class consisting of benzene and naphthalene sulfonate derivatives containing one or more short chain alkyl substituents having about one to four carbon atoms for stabilizing the cosurfactant system and particularly the first hydrophobic nonionic surfactant in the prewash composition, a thickener selected from the class consisting of xanthan gum, polyacrylic acid and polystyrene sulfonate for maintaining viscosity of the composition in a thickened condition in order to maintain the composition in localized engagement on the fabric spots and stains, the thickener forming about 0.1-2 percent by weight of the prewash composition, and water forming the balance of the composition as a predominant component thereof, the hydrotrope being present in the composition in a ratio of at least three parts for each part of the first hydrophobic nonionic surfactant in order to assure stability of the thickened prewash composition.