Abstract: Aluminum silicate or mixtures of aluminum silicate and silica are utilized as insulating materials with low thermal conductivities. The aluminum silicate or the mixtures are dried, compressed, placed in a gas-tight envelope, evacuated and sealed. The resultant rigid, board-like panel can be used directly as thermal insulation or it can be used in conjunction with other insulating materials, for example, polyurethane foam.

Abstract: A method for insulating thermal devices with a composite insulation system including an evacuated powder and a plastic foam. A formed plastic part divides the insulation space between the outer case and inner liner into sectors. Some sectors are filled with a finely divided powder, the remaining sectors are filled with foam, for example, polyurethane. A vacuum is applied to the powder filled sectors while the foam is expanding and curing.

Abstract: Insulating panels are formed from compressed particulate material impregnated with insulating gases, the combination being held in a gas tight pouch. These pouches can be placed in the insulation space of a structure where insulation is to be provided and, if desired, encapsulated in a foamed insulating material. Among the possible particulate materials is precipitated silica, while various Freon gases can be employed as the insulating gas.

Abstract: Precipitated silica is mixed with a fly ash material and is employed as an insulating material having a low thermal conductivity. The mixture of precipitated silica and fly ash material is dried, compressed, placed in an evacuable pouch, and evacuated. The resulting board-like insulation configuration is used directly as insulation. The board-like material which is produced may be used as insulation in household refrigerators and freezers by placing it in an insulation space between the inner liner and the outer case and encapsulating the board-like material with a foamed insulating material.

Abstract: Precipitated silica, formed by the interaction of sodium water glass and sulfuric acid, followed by mechanical processing, is employed as an insulating material having a low thermal conductivity. The precipitated silica is dried, compressed, placed in an evacuable pouch, and evacuated. The resulting board-like insulation configuration is used directly as insulation in, for example, household refrigerators.