U.S. Pat.  No.  4,170,821 issued to Booth on Oct. 16, 1979 discloses a solid water soluble shaving aid incorporated as a strip attached to a disposable razor blade cartridge.  Cartridges having such shaving aids attached to the cap are currently marketed with the aid being mixed in polystyrene.  Currently, polyethylene oxide is the shaving aid preferred.  Examples of cartridges with these soluble shaving aids sold by as "Atra Plus. TM."  by Gillette Company, Boston, Mass. and "Ultrex Plus. TM."  sold by Warner-Lambert Company, Morris Plains, N.J. (Cartridges as used herein are blade assemblies sold as individual items for attachment to a separate handle.  Blade assembly is used generically to include both the cartridge and that part of a unitary disposable razor other than the handle.  The cartridge and blade assembly include at least one blade, a seat for the blade, a guard bar extending from the seat, and a cap and means for separating the blades, if more than one blade is used, and means for maintaining blade position.) 
While location of the lubricating strip on the cap has proven to be desirable because of the liberation of lubricant with each razor stroke, the attachment of the plastic strip in which the polyethylene oxide lubricant has been impregnated, has proven to be difficult.  Both the "Atra Plus" and the "Ultrex Plus" cartridge have the lubricating strip adhesively secured to the cap of the blade assembly.  Adhesive securement requires the separate steps during the manufacturing process of contacting the cap with adhesive, precisely locating the lubricating strip to be in registery with the adhesive and, finally, clamping the strip to insure proper adhesive bonding.  Not only do these additional steps dramatically slow the process but the cost of the adhesive and the problems associated in working with a necessarily quick-drying plastic bonding adhesive with a volatile organic solvent add unnecessary time and complexity to what is otherwise a ultra high speed manufacturing process.