The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 28, 1976
Filed:
Apr. 28, 1975
Bernard T Juba, White Bear Lake, MN (US);
James A Collins, North Oaks, MN (US);
H. B. Fuller Company, St. Paul, MN (US);
Abstract
The disclosed heterogeneous hot-melt sealant system is particularly well suited to sealing the typical tongue-and-groove joint between the base and cover of a burial vault. The hot-melt system comprises a plurality of layers, each layer being a distinct phase which resists chemical or morphological penetration (e.g. paraffin oil migration) from the adjacent layer. The layers are typically applied to the groove in the cover for the vault by individual casting or pouring of each of a plurality of hot-melt compositions in the molten state. Each hot-melt composition comprises an essentially amorphous polypropylene, a hydrocarbon resin (e.g. synthetic terpene resin), and a hydrocarbon (e.g. paraffin) oil. The first (bottom) poured hot-melt contains more polypropylene and less oil and terpene resin than the second (upper) pour. The plurality of layers co-operate to provide a variety of properties including fast sealing (even at low temperatures) and low temperature flexibility (primarily contributed by the upper pour) and good long-term hydrostatic pressure resistance (primarily provided by the bottom pour).