04343127 is referenced by 67 patents and cites 11 patents.

A fire door comprising a core and edge banding, the principal ingredients of the core being expanded perlite, gypsum and cement, and including, as minor ingredients, an organic binder, and having a density not greater than about 35 lbs./cu. ft. The banding comprises composite stiles and rails, each formed of a strip of wood and a strip of a cast mixture of which the principal ingredient is gypsum and including a binder and preferably also including fibers, unexpanded vermiculite and clay.

Title
Fire door
Application Number
10268
Publication Number
4343127
Application Date
January 15, 1981
Publication Date
August 10, 1982
Inventor
Charles W Lehnert
Lake Oswego
OR, US
Dale R Greve
Beaverton
OR, US
Agent
Synnestvedt & Lechner
Assignee
Georgia Pacific Corporation
OR, US
IPC
E04B 2/28
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