James David Benko, Age 611665 S Clearwater Dr, Zeeland, MI 49464

3959166, May 25, 1976

Dec 16, 1974

5/533355

Alfred W. Oberhofer - Downers Grove IL
James J. Benko - Griffith IN
Joseph C. Drozd - Park Ridge IL

Nalco Chemical Company - Oak Brook IL

C11D 732
C09K 1500

252146

A cleaner to be used preferably in conjunction with conventional glycol-type collants in automotive cooling systems and methods of using same. The present cleaners may be referred to as extended-life cleaners which may be added to the glycol coolant and are co-extensive with the life of said glycol. These cleaners operate to dissolve deposits, minimize corrosion damage, and dissolve organic degradation products, all of which cause heat transfer difficulties. The basic cleaner comprises: A. an aminopolycarboxylic acid B. an. alpha. hydroxy acid such as gluconic, tartaric, or citric C. an azole copper protector such as mercaptobenzothiazole (MBT) and a monoaryl triazole such as benzotriazole or tolyltriazole Wherein the above components are combined in a weight ratio ranging from 3:1:1 to 2:1:1. An aqueous concentrate is preferred and in such a concentrate the amount of Deposit Release Agent varies from about 85-15% with a more preferred range being an aqueous concentrate which contains from 50-15% by weight of the Deposit Release Agent. The balance of such concentrate is, of course, water, preferably soft water.

3962109, Jun 8, 1976

Dec 16, 1974

5/533356

Alfred W. Oberhofer - Downers Grove IL
James J. Benko - Griffith IN
Joseph C. Drozd - Park Ridge IL

Nalco Chemical Company - Oak Brook IL

C02B 500

252146

A cleaner-inhibitor and method of incorporating same into an automotive or diesel coolant system consisting of 2-4 fluid ounces per gallon of a cleaner whose basic components are: A. an aminopolycarboxylic acid B. an. alpha. hydroxy acid such as gluconic, tartaric, or citric C. an azole copper protector such as mercaptobenzothiazole (MBT) and a monoaryl triazole such as benzotriazole or tolyltriazole Wherein the ratio of A:B:C is about 3:1:1 to 2:1:1. A, b, and C above constitute a Deposit Release Agent in the cleaner. The cleaner above is combined with an inhibitor which is a multi-component inhibiting composition of the boron-nitrite type containing an alkali metal silicate and which may include a copper inhibitor and a polymeric dispersant, which is a water-soluble carboxylic acid polymer such as styrene maleic anhydride copolymer, a polyacrylate or methacrylate copolymer or carboxymethyl cellulose. The cleaner-inhibitor is adjusted with caustic to give a pH in the range 7. 5-12. 6 and preferably 7. 5-10.