Method of obtaining a seal upon the interior surface of a container closure and resulting product
AssigneeNordson Corporation
InventorsRobert R. Terry, Jacob J. Boone
Life of this patent
Estimating the term…
Abstract
A method for emplacing a seal on a closure for a container which comprises despositing a foamed adhesive in liquid form on an interior surface of the closure and allowing that foamed adhesive to solidify and adhere as a solid cellular foam to the interior surface of the closure.
Claims2
The method of obtaining a seal upon the interior surface of a closure for a container, which method comprises
- heating a thermoplastic adhesive material which is solid at room temperature so as to convert said adhesive material to the molten state,
- creating a mixture of gas and molten thermoplastic adhesive,
- pressurizing said mixture of gas and molten thermoplastic adhesive so as to force said gas into solution with said molten thermoplastic adhesive,
- dispensing the pressurized mixture of gas and molten adhesive at atmospheric pressure onto the interior surface of a container closure, whereby said gas comes out of solution with said molten thermoplastic adhesive and forms a foamed molten adhesive bead upon said interior surface, and
- cooling said foamed molten adhesive bead while maintained as a foam on said interior surface of said closure so as to form a cellular seal adhered to said interior surface of said closure.
Apparatus for creating a seal upon the interior surface of a closure for a container, which apparatus comprises means for heating a thermoplastic adhesive material which is solid at room temperature so as to convert it to the molten state,
- means for creating a mixture of gas and said molten thermoplastic adhesive,
- means for pressurizing said mixture of gas and molten thermoplastic adhesive so as to force said gas into solution with said molten thermoplastic adhesive,
- means for dispensing the pressurized mixture of gas and molten adhesive at atmospheric pressure whereby said gas is released from solution to form a foamed adhesive in an annular pattern on the interior surface of the container closure, and
- means for maintaining said foamed molten adhesive in said annular pattern on said interior surface while said foam is cooled so as to form a solid cellular seal adhered to said interior surface of said closure.
Dependencies are inferred from the claim text.