Abstract: The present invention provides a compliant molded diaphragm which includes an operable surface area for forming a flexiblle barrier to prevent fluid flow between opposing sides of the diaphragm. The diaphragm is formed as a sandwich structure having first and second elastomeric layers and a third gas impermeable layer located between the first and second layers. The third layer may be provided as a thin layer of metal which is vapor deposited between the two elastomeric layers or may be a thin gas impermeable polymer film. The impermeable layer is preferably formed as a grid pattern in the operable surface area of the diaphragm such that portions of the first and second layers are exposed to each other whereby the first and second layers may be bonded to each other to prevent separation of the layers of the diaphragm.

Abstract: A chemical detector employs a very fine serpentine-like groove which is filled with conductive paint, to form an electric circuit. The application discloses a method of making a molded part having such a groove by making a mold insert for a plastic mold in which the mold insert is formed with grooves defining a land pattern which will form the grooves in the molded part. A mold insert is formed with a main block and a pair of side blocks, the main block having twice as many grooves therein as the side blocks so that, when the side blocks are offset with respect to each other, a serpentine-like land pattern is formed in the three blocks.