Detergents for dishwashing machines in the form of fused blocks containing alkali hydroxides and active chlorine and a process for their production

US4729845A · kind A · utility

Assignee

• Henkel Kommanditgesellschaft auf Aktien · DE

Inventors

• Theodor Altenschoepfer · Goldkronach, DE
• Jochen Jacobs · Wuppertal, DE
• Peter Jeschke · Eltville am Rhein, DE
• Klaus Schumann · Weil am Rhein, DE

Key dates

• Filing date: May 29, 1986
• Grant date: Mar 8, 1988
• Expiry date: May 29, 2006

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C11D3/3955
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Detergents for dishwashing machines in the form of fused blocks containing alkali metal hydroxides, alkali metal silicates, and from 0.2 to 4% by weight of active chlorine donors having a hydrolysis constant of 3.times.10.sup.-4 or lower (preferably Na- or K-dichloroisocyanurate, Na-dichloroisocyanurate dihydrate, Na-monochloroamido-sulfonate or Na-N-chloro-p-toluene sulfonic acid amide). The process of making the fused blocks comprises heating metasilicate or waterglass solution with or without solid alkali metal hydroxide to 45.degree. to 48.degree. C., allowing the reaction temperature to rise to 60.degree. to 65.degree. C., adding the remaining ingredients including the active chlorine donor at 50.degree. to 65.degree. C., pouring the still liquid melt into flexible molds and allowing it to solidify into blocks therein. The detergent blocks of the invention have good stability to storage and a high dissolving rate in use.