Abstract A gasket having improved sealing properties and the method of forming such a gasket wherein a continuous strip or web of gasket material is wound on a core with the core having a crosssectional configuration corresponding to the internal configuration of the gasket being made. The web material is wound upon itself and, in the preferred embodiment, has a series of intermediate bonding layers of a fluid-impermeable polymer material which in the end product form a plurality of parallel fluid barriers to produce effective sealing. The winding of the web material on the core and the application of the polymer material to the web provides a tube which is then cut into preselected thicknesses to provide individual gaskets. Additional polymer material may be provided on the cut or exposed surfaces of the gasket is desired. The cross-sectional flange width of the gasket is dictated solely by the convolute gasket material and the polymer material layer or layers. One aspect of the improved method consists in preparing a roll of the gasket material which is to be wound on the core with the base material having applied to one or both sides thereof an adhesive coating which has been dried, at least to the extent that it will not adhere or cohere to itself when rolled upon itself, before the tube is formed. The coatings on the prepared roll may be individually tailored to provide a very thin coating on one side and a relatively thicker coating on the other side which are substantially dimensionally stable when applied to the web and when the prepared material is formed into convolute tubes.
THE METOD OF MAKING A CONVOLUTELY WOUND GASKET CHARACTERIZED BY A HAVING ALTERNATE DISCRETE LAYERS OF CARRIER MATERIAL AND A FLUID-IMPERMEABLE POLYMER MATERIAL COMPRISING: A. TAKING A WEB OF A CARRIER MATERIAL, B. COATING ONE SIDE OF THE WEB WITH A RELATIVELY THIN THICKNESS OF FLUID-TEMPEABLE CURABLE POLYMER MATERIAL WITH A TYPICAL RANGE OF ABOUT 0.0001 INCH TO ABOUT 0.0003 INCH, C. DRYING THE COATEDWEB TO DRIVE OFF VOLATILES TO D. COATING THE OTHER SIDE OF THE WEB WITH A PREDETERMINED GREATER THICKNESS OF FLUID-IMPERMEABLE CURABLE POLYMER MATERIAL IN THE RANGE OF ABOUT 0.0002 INCH TO ABOUT 0.010 INCH, E. DRYING THE DUAL COATED WEB BY DRIVING OFF THE VOLATILES TO PROVIDE A DIMENSIONALLY STABLIZED, SUBSTANTIALLY ADHESION-FREE AND COHESION-FREE, COATED SHEET F. HEATING THE COATED SHEET TO SOFTEN THE COATINGS, G. WINDING THE SOFTENED COATED SHEET IN CONVOLUTE FASHION WITH SUFFICIENT TENSION TO FORM A TUBE WITH DISCRETE FLUIDIMPERMEABLE BARRIERS OF UNIFORM THICKNESS, H. CUTTING THE TUBE INTO INDIVIDUAL GASKETS, AND I. CURING THE FLUID-IMPERMEABLE POLYMER MATERIAL.
Claim 2
Dependent Claim
167 words
THE METOD OF MAKING A CONVOLUTELY WOUND GASKET CHARACTERIZED BY A HAVING ALTERNATE DISCRETE LAYERS OF CARRIER MATERIAL AND A FLUID-IMPERMEABLE POLYMER MATERIAL COMPRISING: A. TAKING A WEB OF A CARRIER MATERIAL, B. COATING ONE SIDE OF THE WEB WITH A RELATIVELY THIN THICKNESS OF FLUID-TEMPEABLE CURABLE POLYMER MATERIAL WITH A TYPICAL RANGE OF ABOUT 0.0001 INCH TO ABOUT 0.0003 INCH, C. DRYING THE COATEDWEB TO DRIVE OFF VOLATILES TO D. COATING THE OTHER SIDE OF THE WEB WITH A PREDETERMINED GREATER THICKNESS OF FLUID-IMPERMEABLE CURABLE POLYMER MATERIAL IN THE RANGE OF ABOUT 0.0002 INCH TO ABOUT 0.010 INCH, E. DRYING THE DUAL COATED WEB BY DRIVING OFF THE VOLATILES TO PROVIDE A DIMENSIONALLY STABLIZED, SUBSTANTIALLY ADHESION-FREE AND COHESION-FREE, COATED SHEET F. HEATING THE COATED SHEET TO SOFTEN THE COATINGS, G. WINDING THE SOFTENED COATED SHEET IN CONVOLUTE FASHION WITH SUFFICIENT TENSION TO FORM A TUBE WITH DISCRETE FLUIDIMPERMEABLE BARRIERS OF UNIFORM THICKNESS, H. CUTTING THE TUBE INTO INDIVIDUAL GASKETS, AND I. CURING THE FLUID-IMPERMEABLE POLYMER MATERIAL.
Claim 3
Dependent Claim
42 words
The method as set forth in claim 1 wherein by use of a heated drum drying means in step e the volatiles are driven from the web material to a substantial extent through the just applied coating of the immediately preceding step.
Claim 4
Dependent Claim
26 words
The method as set forth in claim 1 wherein the cut edges of the individual gaskets are coated with fluid-impermeable curable polymer material and are cured.