Publication Type:Journal Article
Source:Studies in conservation, Volume 3, Number 1, p.40-44 (1957)
Keywords:action, drying, England, England (London), Europe, film, oils, solvents, thickness, UK
Two manometric instruments for the rapid measurement of the thickness of paint and varnish films are described. In the first the probe is a jet of nitrogen emerging from a hypodermic needle which is attached to the focusing movement of a microscope from which the optical parts have been removed. In the second, the needle is replaced by a flat plate pierced by an orifice fed with a solvent, the action of which on the film is measured. The approach of the probe in both cases imposes a back pressure on the gas or solvent flow which makes possible location, and by a calibration, thicknesses are read on the micrometer movement of the microscope. Thus rates of swelling and des welling can be determined. Examples of results published in detail elsewhere are given.