Method for washing clothes, in particular working clothes

US6398820B1 · kind B1 · utility

Assignee

• Henkel Ecolab GmbH & Co. OHG · DE

Inventors

• Thomas Merz · Hilden, DE
• Christine Schnepf · Neuss, DE
• Khalil Shamayeli · Düsseldorf, DE

Key dates

• Filing date: Feb 18, 2000
• Grant date: Jun 4, 2002
• Expiry date: Feb 18, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C11D2111/48
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A process for washing laundry is provided in which a washing alkali component and a surfactant component are combined with water to form a wash liquor, the wash liquor is combined with laundry in a standard washing machine for institutional laundries, and the wastewater from the wash is treated by membrane filtration, where the throughflow rate is reduced by less than 10 percent over an operating time of 120 hours. The washing alkali component is composed of an anionic surfactant and a water-soluble silicate; an alkali metal hydroxide and a complexing agent; or an anionic surfactant and water-soluble silicate and an alkali metal hydroxide, a complexing agent, or a mixture of an alkali metal hydroxide and a complexing agent. The surfactant component is composed of a nonionic surfactant selected from the group consisting of C8-18 fatty alcohol alkoxylates containing at least 5 alkoxy groups, C8-18 fatty alcohol ethoxylates containing at least 7 ethoxy groups, C8-18 fatty alcohol ethoxylate/propoxylates containing at least 4 ethoxy groups and at least 2 propoxy groups in the molecule, and mixtures thereof.