Intumescent material and articles made thereof

Abstract

An intumescent article includes intumescent material including 50-92 wt-% graphite and 8-50 wt-% binder, and may have a free expansion ratio of 100× or greater and a free expansion aspect ratio of 1.0 or less. The intumescent article may be a sheet, and may be L-shaped, rectangle, triangle, or other shape. The intumescent article may have a 3D shape. The intumescent article may be an insert for an electrical box, having a surface area 75% or less of the surface area of the electrical box back wall. The intumescent sheet has a mass, and the ratio of the mass to the volume of the electrical box may be 3 g/100 cm3 or less. A method of making an intumescent article includes mixing from 50-92 wt-% graphite with 8-50 wt-% binder on a dry weight basis to form a mixture, pressing or molding the mixture into a shape and drying the shape.

Dependencies are inferred from the claim text.