Abstract: Industrial woven fabrics made from synthetic fibers are coated with silicone, in particular for use in airbags, by coating the fabric with an aqueous emulsion containing organosiloxanes. The fabrics obtained from the weaving process are coated in the raw state with the aqueous emulsion containing organosiloxanes.

Abstract: The invention refers to a measuring circuit for determining the properties of a workpiece, particularly hardness, using the contact impedance method in which a probe resonating at an ultrasonic frequency provided with a workpiece engaging tip is utilized. The measuring circuit uses digital counters for producing a digital count which is the difference between the free-resonant frequency of the test probe and the resonant frequency of the probe when the probe is in forced contact with the workpiece. A read-only-memory (ROM) converts the difference frequency count to a hardness value, such as Vickers or Rockwell. The disclosed arrangement obviates the need for zeroizing the circuit and, hence, is self-compensating in respect to drift and thermal stability.