Enamel slip properties

The consistent liquid enamel slip properties is a critical parameter at any automated wet application process.

Unfortunately enamel rheology is known to change easily under the influence of particle size, specific weight, temperature, milling additives and/or pretreatment chemicals.

Failure to maintain its properties within measurable tolerances, may result in inconsistent enamel layer thickness and eventually even enamel defects.

Do you really believe that you can “feel it” with your fingers as demonstrated on the picture below, or do you rather prefer a more precise testing method ?!

Measuring enamel slip characteristics by hand
Old fashion way
Rotational Viscometer with temperature sensor
Rotational Viscometer with temperature sensor

Enamelled surfaces & food contact

We received via our network the following press release of TÜV Rheinland LGA Products GmbH

Release from enamelled objects in contact with foodstuffs – Test methods and permitted limits EN ISO 4531 published.

For some years it has been clear that the test conditions (time, temperature) and also the scope of testing of standard EN 1388-2 “Materials and articles in contact with foodstuffs – Silicate surfaces – Part 2: Determination of the release of lead and cadmium from silicate surfaces other than ceramic ware” of 1995, which dates back to a standard of 1985, are no longer up to date.

According to this standard, the release of lead and cadmium is tested at room temperature over 24 hours in 4% acetic acid. This does not correspond by far to the real use conditions, e.g. of enamelled pots. Continue reading “Enamelled surfaces & food contact”