Electrical insulating paper according to an embodiment of the present invention is used while being immersed in electrical insulating oil, and includes a paper base material mainly containing cellulose, an adsorption layer formed on an entire surface of the paper base material by adsorption, and a moisture barrier layer formed by being chemically bonded to the adsorption layer. The moisture barrier layer includes an amphipathic molecule containing both a hydrophobic hydrocarbon group and a hydrophilic functional group in one molecule. The amphipathic molecule is chemically bonded to the adsorption layer via the hydrophilic functional group. The hydrophobic hydrocarbon group covers the surface of the paper base material.

Electrical insulating paper according to an embodiment of the present invention is used while being immersed in electrical insulating oil, and includes a paper base material mainly containing cellulose, an adsorption layer formed on an entire surface of the paper base material by adsorption, and a moisture barrier layer formed by being chemically bonded to the adsorption layer. The moisture barrier layer includes an amphipathic molecule containing both a hydrophobic hydrocarbon group and a hydrophilic functional group in one molecule. The amphipathic molecule is chemically bonded to the adsorption layer via the hydrophilic functional group. The hydrophobic hydrocarbon group covers the surface of the paper base material.

The present application provides wood fiberboard comprising wood fibers bound together with a binder polymer resin that imparts additional strength and moisture resistance. As well, the fiberboard incorporates a thermal fire suppressing inorganic expandable flake graphite and sodium silicate component to render the fiberboard to be non-combustible and fire resistant. As well, a manufacturing process for adding the inorganic graphite and polymer resin binder into the fiberboard and applying the silicate onto the fiberboard is provided.

An acoustical tile including: 8 to 25 wt % mineral wool, 9 to 15 wt % starch binder, 9 to 15 wt % cellulosic fiber, wherein preferably the cellulosic fiber is newsprint, and 40 to 65 wt % perlite, wherein the weight ratio of the starch to the cellulosic fiber is 0.6 to 1.3:1; and a process for making the acoustical tile.

An acoustical tile including: 8 to 25 wt % mineral wool, 9 to 15 wt % starch binder, 9 to 15 wt % cellulosic fiber, wherein preferably the cellulosic fiber is newsprint, and 40 to 65 wt % perlite, wherein the weight ratio of the starch to the cellulosic fiber is 0.6 to 1.3:1; and a process for making the acoustical tile.

An acoustical tile including: 8 to 25 wt % mineral wool, 9 to 15 wt % starch binder, 9 to 15 wt % cellulosic fiber, wherein preferably the cellulosic fiber is newsprint, and 40 to 65 wt % perlite, wherein the weight ratio of the starch to the cellulosic fiber is 0.6 to 1.3:1; and a process for making the acoustical tile.

An acoustical tile including: 8 to 25 wt % mineral wool, 9 to 15 wt % starch binder, 9 to 15 wt % cellulosic fiber, wherein preferably the cellulosic fiber is newsprint, and 40 to 65 wt % perlite, wherein the weight ratio of the starch to the cellulosic fiber is 0.6 to 1.3:1; and a process for making the acoustical tile.