초록 ▼

A double shell filter including an inner shell of bounded 80 to 400 U.S. mesh screen carbon particles and an outer shell of bonded 20 to 80 mesh screen carbon particles wherein the inner and outer particles are bonded internally to each other and the two shells are bonded together preferably by an u

A double shell filter including an inner shell of bounded 80 to 400 U.S. mesh screen carbon particles and an outer shell of bonded 20 to 80 mesh screen carbon particles wherein the inner and outer particles are bonded internally to each other and the two shells are bonded together preferably by an ultra high molecular weight polymer binder having a melt index of less than about 1 gram per ten minutes as determined by ASTM D1238 at 190 degrees C. and 15 kilograms load.

대표청구항 ▼

A method of making a composite charcoal filter having inner and outer shells of two different types of charcoal particles comprising: providing a mold defining the exterior configuration of said composite filter; placing a separator in said composite mold at the desired juncture between said inner a

A method of making a composite charcoal filter having inner and outer shells of two different types of charcoal particles comprising: providing a mold defining the exterior configuration of said composite filter; placing a separator in said composite mold at the desired juncture between said inner and outer shells; mixing said inner shell carbon material with a binder and filling it into said mold to the inside of said separator; mixing said outer shell carbon material with said binder and filling it into the space to the outside of said separator, said binder comprising a low melt index polymeric material having a sufficiently low melt index that it will tackify at elevated temperatures without becoming sufficiently liquid to substantially wet the carbon particles in order that diminution of the effective caron surface is minimized; and removing said separator and subjecting said two different carbon materials and their binders to heat and pressure to cause said carbon particles to bind to each other and to cause said inner shell of carbon material to bond to said outer shell of carbon material whereby an integral composite filter can be obtained, wherein said heat and pressure are applied such that said binder does not become sufficiently liquid to substantially wet the carbon particles in order that diminution of the effective carbon surface is minimized.