Junkosha Co., Ltd.

Toudai Tlo, Ltd.

Satoshi Tanaka

Masahiro Suzuki

Satoru Kobayashi

Tetsuya Hirose

Haruo Imaizumi

Naoko Hattori

Jun Ohgane

Takuya Imamura

Koichiro Nishino

Soshi Yamamoto

Naka Hattori

A multilayer circuit board is provided having an inner porous fluororesin layer containing electrical circuits, a ground conductor layer located adjacent the fluororesin layer on one side thereof and a power supply conductor layer located adjacent the fluororesin layer on the other side thereof, and a reinforcing, solid plastic dielectric layer adjacent each conductor layer and being external to the inner fluororesin layer. In an alternate embodiment, the multilayer circuit board may have a plurality of inner porous fluororesin layers, at least one fluororesin layer containing electrical circuits, and may have ground conductors and power supply conductors adjacent each fluororesin layer, and reinforcing, solid plastic dielectric layers on the outermost surfaces of the circuit board assembly. The ground and power supply conductor layers extend over the entire surfaces, respectively, of the inner fluororesin layers.

Multilayer circuit board

A process is provided for making a laminated board useful in printed circuitry. The process involves laminating a metal layer to at least one side of a sheet of porous, expanded polytetrafluoroethylene using an adhesive followed by compressing the polytetrafluoroethylene sheet to increase its density. The metal layer may be a metal foil or it may comprise electrical circuitry. Also provided are printed circuit boards produced by the aforesaid process.

Laminated printed circuit board and process for its manufacture

A detector for detecting leaks of a corrosive liquid such as strong acids or bases is provided comprising a light guide core having a covering which generates heat upon contact with the liquid to the detected, thereby changing the light transmissivity of the light guide, which change can be measured. The covering comprises a porous polymer having a salt within its pores such as an ammonium salt which dissolves in the liquid to be detected and generates heat thereby.

Corrosive liquid leak detecting sensor

A sensor for detecting leaks of a corrosive liquid is provided comprising a pair of plate electrodes made of a conductive metal which is corroded by the liquid to be detected spaced apart and separated by an inner sheet of an electrically insulating material, the inner sheet having a plurality of through-holes, this entire construction being sealingly encased between a pair of outer insulating sheets, at least one of which has a plurality of through-holes. In use, if a leak occurs the liquid passes through the through-holes in the outer insulating sheet, dissolves a portion of one electrode and passes through the through-holes in the inner sheet to the second electrode, causing a short circuit resulting in a rapid and accurately measurable decrease in the resistance in the circuit and, therefore, detection of the leak.

Sensor for detecting leaks of corrosive liquid

Growing community of inventors

Saitama, Japan

Satoshi Tanaka