Dielectric material and method of making the dielectric material

Claim 1

A non-porous dielectric sheet material wherein the dielectric constant is substantially isotropic, said sheet material comprising a fluorinated polymer binding selected from the group consisting of polytetrafluoroethylene, fluorinated poly (ethene-co-propene), polyolefins, polyacrylates, polystyrenes and poly (vinylidene fluoride), a ceramic filler in particulate form having an average particle diameter of between about 1 to 20 micrometers and non-conductive inorganic microfibers having an average diameter less than 2 micrometers selected from the group consisting of glass, aluminum silicate, potassium titanate, quartz and zirconia, the ratio of the weight of fibers to total non-filler being in the range of 0.07 to 0.20 and the filler comprising between 10% and 75% by weight of the dielectric material.

Claim 8

A method of making a non-porous isotropic dielectric sheet material which has desirable strain relief characteristics in the X and Y directions, a substantially isotropic dielectric constant and a water absorption less than 0.5% comprising the steps of: mixing a dispersion of fluorinated polymer selected from the group consisting of polytetrafluoroethylene, flourinated poly (ethene-co-propene), polyolefins, polyacrylates, polystyrenes, and poly (vinylidene flouride) particles with a dielectric filler material in particulate form and nonconductive inorganic microfibers selected from the group consisting of glass, aluminum silicate, quartz, zirconia and potassium titanate to form a slurry, the slurry comprising enough filler and fibers to obtain in the final product between 10% and 75% by weight of the filler and between 7% and 20% fibers of the total non-filler content; agglomerating the polymer particles, the ceramic filler particles and the microfibes to provide a mass of dielectric material; shaping said mass; and subjecting the shaped mass to heat and pressure to densify the dielectric material.

Claim 9

A method of making a non-porous isotropic dielectric sheet material which has desirable strain relief characteristics in the X and Y directions, a substantially isotropic dielectric constant and a water absorption less than 0.5% comprising the steps of: mixing a dispersion of fluorinated polymer selected from the group consisting of polytetrafluoroethylene, flourinated poly (ethene-co-propene), polyolefins, polyacrylates, polystyrenes, and poly (vinylidene flouride) particles with a dielectric filler material in particulate form and nonconductive inorganic microfibers selected from the group consisting of glass, aluminum silicate, quartz, zirconia and potassium titanate to form a slurry, the slurry comprising enough filler and fibers to obtain in the final product between 10% and 75% by weight of the filler and between 7% and 20% fibers of the total non-filler content; agglomerating the polymer particles, the ceramic filler particles and the microfibes to provide a mass of dielectric material; shaping said mass; and subjecting the shaped mass to heat and pressure to densify the dielectric material.