Defoamers and corrosion inhibitors from C. H. Erbsloh

Excerpt: Coating adhesives for the paint, coatings, adhesives and architectural segments account for nearly 30 percent of C. H. Erbsloh's worldwide turnover.

“We are an over 100 year old Germany-based company and very well accepted all over Europe and other high-technology countries,” said Dr Weinmann. “Since the time when Carl Hugo Erbsloh founded the company C. H. Erbsloh as a wholesaler for chemicals in 1876, we have been successful in fulfilling the role as a link between suppliers for specialty chemicals and industrial minerals to the industry.”

To improve their position further, they now operate with affiliated companies and co-operations in Europe and Asia. “At present, we are concentrating on a few countries in Asia like Indonesia and Thailand, and of course India. In India, we have a reliable and pushing partner in Unique Specialty Chemicals (,” said Dr Weinmann. “Unique Specialty Chemicals ( is already a well-established company in India and can give the customer the whole portfolio of products.”

Coating adhesives for the paint, coatings, adhesives and architectural segments account for nearly 30 percent of C. H. Erbsloh's worldwide turnover.

From numerous range of defoamers presently available with C. H. Erbsloh including the well established CHE COAT DF 6684, The new Grade CHE COAT DF-1110 and 1120 are going to create demand in markets of India and also worldwide. These grades are 100% mineral oil based. Both anti-foaming agents can be used with water-based coatings, such as matt or silk paints, clear wood coatings and wood stains. It is also applicable in adhesives. Easy incorporation is achieved with longer stability of products. Other conventional Anti-foaming agents are added half at the let-down stage while C. H. Erbsloh above grades only need one-third of addition. Providing this it can also diluted with water for even easier addition. Difference between both products is a slightly higher amount of alkoxylated compounds in DF 1120 what increases compatibility at the cost of efficiency of de-foaming.

Foam consists of stabilized air/gas bubbles in a liquid and pure liquids do not foam. Surfactants, surface active agents are foam stabilizing substances; additives like emulsifiers, wetting agents or dispersing agents could react as surfactant. Orientation of their hydrophobic and hydrophilic groups enables the formation of gas bubbles. As the defoamer destroys existing foam and prevents the formation of gas bubbles, they must be insoluble in the system; must have a low surface tension; must have a positive penetration coefficient; must have a positive spreading coefficient; and should be dispersible in the system.

Limited controlled incompatibility of defoamer is also essential. Very compatible means no defoaming effect, or foam stabilization. Too incompatible means very good defoaming, but cratering, and hazy. The optimal is good defoaming, no surface damages, and no turbidity.

The criteria for selection are balance between effectiveness and compatibility. “In defoamers, we have a broad range. So, we will find a solution for the customer. We are very 'flexible,' and that is the key word,” said Dr Weinmann. “We are also one of the few companies selling flash rust inhibitors,” said Dr Weinmann.

Corrosion is a chemical reaction at the bounding surface between metal and coating, enhanced by water, acids or salts. The water-based coatings are attacked by flash-rust as a result of corrosion during storage, application or film-formation. Corrosion and flash-rust lead to damage of the metal and loss of essential material properties.

To prevent this, C. H. Erbsloh offers another product the CHE®-COAT-CI. CHE®-COAT-CI products are water-based solutions of anti-corrosive salts, e.g. nitrites, amines, carboxylates, phosphates, borates, in synergistic combinations.

They are effective between coating and metal and they avoid corrosion and flash-rust through improvement of the film-adhesion; formation of a passivation layer; decrease of film-permeability; electrical inhibition.

The CHE®-COAT-CI L8AF, L8NF is a two-component product. The L8AF is the amine-free part, and the L8NF, the nitrite-free part. This product prevents the formation of toxic nitrosamines and the loss of effectiveness during storage. Easy to handle, both components are added without premix.

There are suitable grades offered for several applications of water-based coatings, different binder systems and protected metals. All the grades are effective on steel and iron. There are special grades for application on other substrates. For example copper: L52, LNF1, LNF2; aluminum, zinc: LAF1, LNF1, LNF2, LNFA4. The typical dosage level is 0.2 – 2.0 w/w %, post-addition recommended.

Also planned is a green version of corrosion inhibitors which will be introduced shortly.

While distributing high quality additives of other manufacturers, C. H. Erbsloh too has entered the manufacturing line with their own range of products. “The idea is to increase the share of our products,” said Dr Weinmann. “We have our own application laboratories where we develop new products as well as find new applications.”

At present, all their products are made in Europe and shipped across to Asia and other parts of the world. “We are here in India the last four years. Making your presence felt is a time consuming process. First the customer will have a test run with our products, assess the performance, and only then will they go in on a commercial scale. All this takes time. After all, we are here to be in India. This is an important market. We want to be noticed, and we are sure we will be here for a long, long time to come!”

Further information can be had from:

Author Details

Dr. Klaus Weinmann & Neerav Thacker

Unique Speciality Chemicals