Fire-resistant article and method of manufacture
AssigneeGeorgia-Pacific Corporation
InventorsGeorge F. Fowler, Jr., Charles W. Lehnert
Life of this patent
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Abstract
A fire-resistant article, for example, a fire door core comprising a major amount of expanded perlite in compressed form, an adhesive material, the major portion of which is starch, and preferably glass fibers, and a method for making the article by dry-mixing the ingredients substantially completely before water is added for the purpose of developing the adhesive characteristics of the starch.
Claims18
A method for making a fire-resistant article from a composition which includes a major amount of a light-weight friable material and other materials in particulate form, including starch adhesive, comprising:
- (A) dry-mixing a major amount of expanded perlite and a minor amount of an adhesive material, the major portion thereof being gelatinized starch, for a period of time sufficient to produce a mixture in which the constituents thereof are distributed uniformly therethrough;
- (B) wetting said particulate materials by applying thereto water at a time just prior to or upon the formation of said mixture;
- (C) continuing the mixing to distribute the water throughout said mixture;
- (D) promptly shaping said wetted mixture after its formation into the form of said article under conditions which involve compressing a supported form of said mixture;
- (E) recovering in an unsupported form the freshly shaped and compressed mixture, the green strength thereof being sufficiently high for the shaped mixture to be shape-retaining and to be handled without damage;
- and thereafter (F) drying said mixture.
A light-weight, fire-resistant article comprising a major amount of expanded perlite in compressed form and a minor amount of an adhesive material, the major portion thereof being gelatinized starch, said article having a density of no greater than about 22 lb/cu ft.
Dependencies are inferred from the claim text.