Sleeve-type closures for dispenser nozzles

Abstract

Reusable sleeve closures comprising a flexible thin sleeve of film grade plastic which seals the nozzle of a partially used sealant, mastic or caulk-dispensing cartridge or squeeze tube to substantially retard the hardening of the remaining tube contents. The plastic film provides a vapor barrier against exit of water or organic solvent from the sealant composition, and/or retards diffusion of oxygen that could cause the composition to set. The film is preferably somewhat stretchable and without creep over time, so that the sleeve provides an extremely tight seal for a substantial distance along the nozzle, e.g. film grade polyolefin or polyvinylidene chloride copolymer plastic film. The sleeve length is preferably long enough to provide a head space for a visual and tactile indicator of content condition. Sleeves may be packaged with the cartridge, or provided after-market. A 4-mil film polyolefin sleeve preserves water-based acrylic caulk over 9 months.

1 . A sleeve-type seal device for post-use sealing of sealant and mastic composition-containing dispenser cartridges and squeeze tubes, comprising in operative combination: 
 a) a sleeve of flexible film grade plastic film having a composition and thickness selected to provide a vapor barrier to retard solvent evaporation from the composition in said cartridge or tube, and retard permeation there through of such quantities of oxygen as would cause the residual composition to set;    b) said sleeve includes a nozzle-receiving pocket having margins selected from an open lower end, a closed upper end and an encircling side wall;    c) said sleeve pocket has a width smaller than a medial diameter of said nozzle, and said sleeve has a length ranging from about 0.5 to about 1.25 times the length of said nozzle; and    d) said sleeve, upon mounting on said nozzle, stretches sufficiently to create a substantially hermetic seal along a substantial length of said nozzle to assist in retaining said residual composition in useful condition.    
     
     
         2 . A sleeve-type seal device as in    claim 1    wherein said sleeve plastic film has a thickness of from about 1 to about 10 mils, and said hermetic seal is formed along from about 25% to 100% the length of said nozzle.  
     
     
         3 . A sleeve-type seal device as in    claim 1    wherein said pocket margins include at least one margin defined by a seam.  
     
     
         4 . A sleeve-type seal device as in    claim 3    wherein said at least one margin is said top end.  
     
     
         5 . A sleeve-type seal device as in    claim 1    wherein a plurality of said sleeve-type sealing devices are included in a strip, each device being separable from said strip along at least one line of perforations.  
     
     
         6 . A sleeve-type seal device as in    claim 3    wherein a plurality of said sleeve-type sealing devices are included in a strip, each device being separable from said strip along at least one line of perforations.  
     
     
         7 . A sleeve-type seal device as in    claim 3    wherein said sleeve is formed from at least two overlying plastic sheets.  
     
     
         8 . A sleeve-type seal device as in    claim 7    which includes at least two seams defining margins of said pocket, including at least one side margin.  
     
     
         9 . A sleeve-type seal device as in    claim 8    wherein said at least two seams are side margins.  
     
     
         10 . A sleeve-type seal device as in    claim 8    wherein said seams are one side seam and one top seam.  
     
     
         11 . A sleeve-type seal device as in    claim 8    wherein said seams are two side seams and one top seam.  
     
     
         12 . A sleeve-type seal device as in    claim 9    wherein at least one sheet of said plastic sheet extends outwardly beyond at least one of said pocket side margins to provide a flap for handling said sleeve to assist in seating the pocket on a nozzle and in removing said sleeve therefrom.  
     
     
         13 . A sleeve-type seal device as in    claim 1    wherein said pocket is formed of tubular material, and said upper end is formed by a seam extending transversely across said tube.  
     
     
         14 . A sleeve-type seal device as in    claim 13    wherein a plurality of said sleeve-type sealing devices are included in a strip, the transverse seams being spaced apart along said strip an amount ranging from about 0.5 to 1.5 times the length of a nozzle, each sleeve device is separable from said strip along at least one line of perforations, said perforations defining an open end margin of said pouch.  
     
     
         15 . A sleeve-type seal device as in    claim 1    wherein a plurality of said sleeve-type sealing devices are packaged in association with a cartridge or squeeze tube.  
     
     
         16 . A sleeve-type seal device as in    claim 15    wherein said associated packaging includes a pouch adhesively removably attached to said cartridge or tube.  
     
     
         17 . A sleeve-type seal device as in    claim 15    wherein said plurality of sleeve-type sealing devices is packaged in a bag removably secured to a header card.  
     
     
         18 . A sleeve-type seal device as in    claim 15    wherein said plurality of sleeve-type sealing devices is packaged in a roll wrapped around a nozzle.  
     
     
         19 . A sleeve-type seal device as in    claim 1    wherein the pocket length ranges from about 2″ to about 3″ (from about 5 to about 8 cm), and the width of the pocket (diameter when opened) is such as to ensure that the pocket can be slipped over substantially the length of the nozzle, while forming a tight seal area on said nozzle on the order of at least about 1″ in length.  
     
     
         20 . A sleeve-type seal device as in    claim 1    wherein the pocket width is substantially the width of the nozzle at the shoulder where the nozzle tip taper meets the shank of the nozzle.  
     
     
         21 . A sleeve-type seal device as in    claim 1    wherein the pocket width, for a conventional dispenser cartridge having a cut nozzle length on the order of 2¾″ (7-7.3 cm), ranges from about {fraction (12/32)}″ to about ¾″ (from about 1 to about 2 cm).  
     
     
         22 . A sleeve-type seal device as in    claim 1    wherein the pocket width ranges from about {fraction (14/32)}″ to about {fraction (16/32)}″ (from about 1.1 to about 1.3 cm).  
     
     
         23 . A sleeve-type seal device as in    claim 14    wherein said perforations are spaced from said transverse seam an amount of up to about ¾″.  
     
     
         24 . A sleeve-type seal device as in    claim 6    wherein said pocket side margins are tapered.  
     
     
         25 . A sleeve-type seal device as in    claim 24    wherein said devices are oriented in opposing, alternating configuration in said strip.  
     
     
         26 . A sleeve-type seal device as in    claim 2    wherein said plastic is selected from a polyolefin plastic or a polyvinylidene chloride-containing polymer film.  
     
     
         27 . A sleeve-type seal device as in    claim 26    wherein said polyolefin film contains at least one of polyethylene and polypropylene.  
     
     
         28 . A sleeve-type seal device as in    claim 27    wherein said polyolefin film has a thickness in the range of from about 2 to about 7 mils.  
     
     
         29 . A method of retarding setting of residual sealing and mastic composition left over after use in dispenser cartridges and squeeze tubes having nozzles for dispensing compositions from cut-open tips thereof, comprising the steps of: 
 a) inserting said nozzle in a sleeve-type seal device of thin flexible somewhat stretchable plastic sheet having a nozzle-receiving pocket, said plastic providing a vapor barrier to retard solvent evaporation from the composition in said cartridge or tube, and retard permeation there through of such quantities of oxygen as would cause the residual composition to set; and    b) seating said pocket on the shank of said nozzle to form a tight, elongated substantially hermetic seal area around said nozzle, said elongated seal area extending from about 25% to about 100% of the length of said nozzle shank.