Abstract: Dielectric protective cover for a lightning arrester with an early streamer emission device, wherein the lightening arrester includes an active portion for connection to the early streamer emission device for promoting a triggering of an upward leader from the active portion, a down conductor for connection to ground, and a dielectric portion for mounting the active portion on the down conductor, the active portion being separated from the down conductor by an air space formed as a spark gap through which lightning current will pass from the active portion to the down conductor, the protective cover comprising: a first portion for fastening to the active portion; and a second portion for fastening to the down conductor, wherein the protective cover protects dielectric properties of the spark gap against degradation in an environment of the spark gap, while leaving the active portion exposed to the environment.

Abstract: Dielectric protective cover for a lightning arrester with an early streamer emission device, wherein the lightening arrester includes an active portion for connection to the early streamer emission device for promoting a triggering of an upward leader from the active portion, a down conductor for connection to ground, and a dielectric portion for mounting the active portion on the down conductor, the active portion being separated from the down conductor by an air space formed as a spark gap through which lightning current will pass from the active portion to the down conductor, the protective cover comprising: a first portion for fastening to the active portion; and a second portion for fastening to the down conductor, wherein the protective cover protects dielectric properties of the spark gap against degradation in an environment of the spark gap, while leaving the active portion exposed to the environment.

Abstract: A photosensitive composition having contrast and selectivity, useful in forming high resolution patterns.The composition comprises a phenolic resin, a diazoquinone compound and an aromatic fused polycyclic sulfonic or carboxylic acid, in the form of the free acid and/or an ammonium salt and/or an acid halide, the cation component of the ammonium salt having the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, each represent hydrogen, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -hydroxyalkyl.In forming a negative pattern, the composition is coated on a substrate and exposed imagewise to ultraviolet radiation, thereafter treated with a silicon compound, whereby the silicon compound is selectively absorbed into the irradiated portions and the non-irradiated portions are then removed by dry etching.

Abstract: A photosensitive composition having increased contrast and selectivity, useful in forming high resolution patterns. The composition comprises a phenolic resin, a diazoquinone compound and an aromatic fused polycyclic sulfonic or carboxylic acid, in the form of the free acid and/or an ammonium salt and/or an acid halide, the cation component of the ammonium salt having the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, each represent hydrogen, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -hydroxyalkyl.In forming a negative pattern, the composition is coated on a substrate and exposed imagewise to ultraviolet radiation, thereafter treated with a silicon compound, whereby the silicon compound is selectively absorbed into the irradiated portions and the nonirradiated portions are then removed by dry etching.

Abstract: A radiation-sensitive resin composition comprising a quinonediazide-type radiation-sensitive resin and a compound generating an acid upon irradiation. Said radiation-sensitive resin composition can be used as a resist suitable for dry development by plasma etching and enables one to obtain an etching image having high precision with high reproducibility at a high degree of resolution and selectivity.

Abstract: A method for high temperature reaction process, including the steps of mounting a substrate on which a radiation-sensitive polymer film is formed on a lower heating plate in a reaction vessel, sealing the reaction vessel while positioning an upper heating plate to above the substrate, maintaining a temperature difference between temperatures of the lower heating plate and the upper heating plate within a predetermined range, and supplying a reactive compound into the reaction vessel.