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.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] The benefit is claimed under 35 USC § 119 (e) of the filing date of Provisional Application Ser. No. 60/179,585 filed Feb. 1, 2000 under the same title by the same inventor.

FIELD

[0002] The invention relates to closures for nozzles of dispensing cartridges and squeeze tubes, more particularly to a flexible sleeve of plastic film that hermetically seals the nozzle of a fresh or partially-used sealant, mastic, adhesive, glazing or caulk-dispensing cartridge or squeeze tube so that the remaining unused contents do not set. The sleeve(s) may be packaged with the cartridge, or may be provided as an after-market replacement used alone or in combination with ordinary nozzle caps.

BACKGROUND

[0003] It is common practice to package sealant, mastic, adhesive, glazing, caulk and glue compositions in plastic or metal squeeze tubes, or plastic or plastic coated or impregnated paper cartridges which are adapted to be loaded into extrusion devices, ordinarily called caulking guns, in order to dispense the sealant compositions. Conventional sealant cartridges comprise an elongated cylindrical body or tube and nozzle with an exit orifice. The nozzle is typically mounted to a top end piece, or is molded integrally therewith or is part of a 1-piece, all plastic dispenser or squeeze tube construction. A movable diaphragm or piston is disposed within the cylindrical body at the end opposite the nozzle. The cavity defined between the piston and top end contains the sealant composition. The nozzles are typically round or, in the case of window glazing compound, square in cross-section. The nozzle length varies; for typical caulk tubes, the nozzles vary from about 1½″ to about 3″-4″ in length, for commercial construction and deep injection (e.g., urethane marine adhesive sealants or dry rot fillers), the nozzles typically exceed 5″ in length.

[0004] In use, the tip of the plastic nozzle is ordinarily trimmed off diagonally, and a thin sealing membrane is then burst or punctured, e.g., with a nail, rod, or the like, inserted in the open nozzle. In the case of window glazing tubes, the square nozzle is usually formed with a diagonal opening and a trailing smoothing lip, so no cutting is required. Thereafter the cartridge is placed in the caulking gun, actuated with the ratcheting lever-type handle and the sealant dispensed as needed.

[0005] It is ordinarily the case that the quantity of sealant or mastic composition that comes in the dispensing tube does not match the amount required for a particular given job. After dispensing the required amount, there is usually some portion of the contents that is unused. Where there is no foreseeable immediate future use for additional quantities, the dispensing cartridge with its unused portion is often discarded. In addition to being uneconomic, disposal of excess composition represents a considerable waste of resources and is highly undesirable for environmental reasons. At present, there is no known recycling available for the wide variety of sealant and mastic compositions being distributed today.

[0006] Where there is a possible or intended future use of residual composition, a variety of solutions have been tried to prevent the setting of unused composition in the cartridges. Cartridges often come with plastic caps, some of which have nozzle-engaging snap-fit bead(s) and groove(s), or screw threads, so that the cap does not easily come off. However, since the plastic of which the caps and nozzles are made has very low tensile strength, it is easy to over-tighten the screw caps, causing them to split. Likewise, a bead and groove does not provide a hermetic seal for any substantial length of time. Other solutions involve placing a large nail down into the tube opening, to effect a plug type seal. In this latter class of approaches is included a flat-ended plastic cap with a male plug member located axially in the cap. The cap slips over the outside of the nozzle while the plug fits internally in the nozzle bore. These solutions are temporary at best and typically do not prevent drying out of the contents for more than a few weeks, especially when there is residual pressure on the contents, which results in pushing off the cap.

[0007] Among other common approaches used by workmen include wrapping the tip with aluminum foil or plastic kitchen wrap, secure that with a rubber band, and/or optionally place the entire tube in a recloseable type plastic bag, such as a Ziploc® brand sandwich or food bag. However, most tubes do not fit in Ziploc® bags, the plastic is thin (on the order of 1 mil or less), and the bags with the cartridge in them contain so much air as to defeat the purpose. Plastic kitchen wrap is very thin, on the order of 0.4 mil or less, and does not cling to plastic nozzles. Neither the foil or wrap can be tightly wrapped around the nozzle without some air/vapor gaps. Further, some types of kitchen wrap are designed to be breathable, that is, they permit permeation of oxygen therethrough for food freshness purposes. The wrapping approach simply does not provide an adequate seal.

[0008] Another class of packaging for sealants and other types of caulks are squeezable or collapsible tubes, which typically contain about one-tenth to one-quarter the amount of material as is contained in dispensing cartridges. These sealant tubes are ordinarily provided with screw-on or multi-bead/groove caps. However, they also suffer from the problem of the caps splitting when they are screwed down too tightly, or not providing a good hermetic seal when the threads, beads or grooves become clogged with partially set or dried sealant material. Finally, this class of packaging also suffers from the same types of poor cap fit problems as the more common caulk tube type dispensing cartridges.

[0009] Thus, in both classes of sealant and mastic packaging (cartridges and squeeze tubes), where the contents of the cartridge or tube are not entirely dispensed during a particular caulking or gluing operation, if precautions are not taken to carefully and redundantly reseal the nozzle, the remaining caulking compound will harden, due to exposure to the atmosphere. This arises in two ways: first, some of the sealing or mastic compositions have volatile components that upon evaporation will harden. Others are primarily or entirely water-based, and harden upon evaporation of the water. Still others are settable by exposure to oxygen of the atmosphere, which enters by a poor seating of the cap, via gaps in foil wrapping, or permeates through thin, hand-wrapped plastic wrap.

[0010] The term sealant as used herein includes the entire variety of caulk, adhesive or mastic-type materials currently offered in dispensing cartridges and squeeze tubes, such as but not limited to: stucco, concrete and cementitious-material patching and crack filling compounds; gasketing compounds; latex or acrylic caulk or filler compounds; gutter, flashing, skylight, or fish tank seam or sealant compounds; butyl or rubber sealants, cements and caulk; roof cements; panel and construction adhesives; glazing compounds and caulks; gutter and lap sealants; silica gel-based firebrick, masonry and ceramic crack fillers, caulk and cements; silicone-based glues, adhesives and caulks; urethane caulks and adhesive sealants; ethylene glycol-containing latex glazing compounds; and the like. Well known sealant manufacturers include: Dow Coming; DAP, Inc.; GE Silicones; 3M; Red Devil; Sashco Sealants, Inc.; Maaco (Liquid Nails) division of ICI, Int'l; ChemRex, Inc.; and OSI Sealants, Inc., a subsidiary of Sovereign Specialty Chemicals, Inc.

[0011] Thus, there is a well-recognized but long unmet need to provide a truly hermetic nozzle seal to retard setting of the remaining contents of partially-used dispensing cartridges and squeeze tubes. The invention provides a simple, cost-effective and unexpectedly superior solution to the problem, as shown in actual tests.

THE INVENTION

[0012] Summary, Objects and Advantages:

[0013] The invention comprises a flexible sleeve of plastic film which tightly fits over the open nozzle of sealant dispenser cartridges and squeeze tubes to provide a hermetic seal to prevent or substantially retard, on a long term basis, the hardening of the remaining contents of the cartridge or tube after its initial use. The plastic film may range widely in composition and thickness including multi-layer and copolymer film, so long as it has the functionality of providing a vapor barrier against exit of water or organic solvent from the sealant composition, and prevent or retard diffusion thereinto of such quantities of oxygen as would cause the composition to set in the case of air-settable compositions. The plastic film is preferably heat sealable, somewhat stretchable and not subject to substantial relaxation or creep over time, so that when the sleeve is inserted over the open nozzle and pulled or pushed downwardly thereon, it provides an extremely tight seal for a substantial distance along its length.

[0014] The present best mode of the invention comprises providing a tightly fitting sleeve made of slightly to moderately stretchable thin plastic sheet or film material. In the case of water-based compositions, e.g., acrylic caulk, and hydrocarbon solvent-containing mastics, and silicones (which give off acetic acid) a suitable film or sheet plastic is a film grade polyolefin plastic such as low density polyethylene or polypropylene, or copolymers thereof or with other alpha olefins. For urethanes, such as 3M brand marine adhesive sealants and Lexcel brand copolymer rubber-based sealants (which contains polyurethane prepolymer, heptane, acetone and toluene diisocyanate), the preferred plastic material is Saran® (an S. C. Johnson brand) monolayer film, or Saran®/polyethylene multi-layer film. Saran® films are copolymers of vinylidene chloride and methyl acrylate or vinyl chloride, or copolymers of vinylidene chloride and one or more of methacrylonitrile and methyl methacrylate, and useful films include “Saran® 100 HB” film or “Saran® 560 Industrial” film, both of which are biaxially oriented monolayer films having very high moisture and air barrier properties. The plastic sleeve film is selected to have a typical thickness on the order of from about 1 to about 10 mils, preferably about 3 to about 7 mils. Typically, the polyvinylidene chloride films can be thinner, about ½ to ¼ the thickness of the polyolefin films.

[0015] It is preferred that the film have good heat sealing properties, such as is obtained with a film grade low density polyethylene or a vinylidene chloride copolymer. Film grade polyethylenes are understood in the art to include copolymers or blends to reduce the density from pure polyethylene. HDPE is not recommended, and oriented plastic film is not required but may be employed. The polyolefin films included in this invention are excellent without modification for water-based, and acetic acid-containing sealants and mastics, such as acrylic-containing caulking compounds and silicone cements and caulks. In the case of mastics having organic solvents, most now are low VOC compounds and a polyolefin film at the thicker end of the above range is preferred to resist vapor permeation. However, where the hydrocarbon solvent content is high and/or the polyolefin swells on exposure to the mastic, a multi-layer film which includes a barrier layer that is low or non-permeable to organics and/or oils is preferably employed. While not intending to be bound by specific examples, barrier layers which may be considered include film PVA, PVC, PETE, and vinylidene chloride polymers or copolymers. It is a straight-forward matter for one skilled in the art to select an appropriate film and/or barrier layer based on the required properties outlined above from amongst various commercial films, and may include any somewhat stretchable, preferably heat sealable film grade, single layer or multi-layer film of homogeneous or heterogeneous composition.

[0016] In a first embodiment, a strip of film grade plastic film is folded over on itself, typically in half parallel to its long axis, and the resulting two sheets sealed together along two spaced lines to provide a straight or slightly tapered pocket there between. The seal lines may be formed by use of glue, solvent, RF, heat, radiation or the like, with heat sealing being the presently preferred embodiment. However, it should be understood that reference to heat sealing herein is merely by way of example and any convenient seam sealing technique may be used. The lines of heat seals may be disposed inwardly from the marginal edges of the superimposed plastic sheets to form handling “wings” or flaps between the seal lines and the side marginal edges. These wings can be used to push or pull the sleeve down over the nozzle and for removal. The folded end forms the top or tip of the sleeve, and the unsealed opposite end of each sleeve provides an opening for access of the nozzle into the sleeve pocket formed between the top, the side seams and the bottom marginal open edge. Alternately, the pocket may be a tube with no side seams, or with a single side seam, and a top seam.

[0017] The pocket at its open end is dimensioned to provide a tight fit around the base of the nozzle as it joins the top end face of the dispenser cartridge or squeeze tube. Nozzles for squeeze tubes are on the order of 1½″±⅜″ (3.5-4.5 cm) long, while consumer (homeowner) cartridge nozzles are typically 2⅝″±¼″ (6.5-8 cm) in length, and commercial, marine, special type, and large commercial construction cartridge nozzles are on the order of twice as long. The length of the pocket is long enough to provide a good hermetic seal of from about 25% to about 100% of the nozzle length. Typically the pocket will range from about 0.5 to about 1.25 times the length of the nozzle, preferably longer than the length of the nozzle. For the above consumer cartridge nozzle dimension, the pocket will typically be about 2″-3″ (5-8 cm) in length, proportionally shorter for squeeze tube and proportionally longer for commercial, marine, etc., nozzles.

[0018] The width A (see FIG. 2) of the pocket is such as to ensure that it can be slipped substantially down the length of the nozzle, while forming a tight seal area of from about 25% to about 100% the length of the nozzle. For a consumer cartridges, that provides a minimum seal area on the order of about 1″ in length, preferably about 2″ inches in length (2.5-5.2 cm), and for other cartridges, such other length as is feasible for however long the nozzle may be to its diagonal or transverse cut or opening. Since nozzles are tapered, the width between pocket side seams should be no more than the diameter of the nozzle where the seal is selected to be started (position below the cut tip end). Typically the minimum width is preferred to be the width of the nozzle at the shoulder where the nozzle tip taper meets the shank of the nozzle, and for a conventional consumer type dispenser cartridge having a cut nozzle length on the order of 2¾″ (7-7.3 cm), this width is suitably on the order of {fraction (12/32)}″ to ¾″ (1-2 cm), preferably about {fraction (14/32)}″ to {fraction (16/32)}″ (1.1-1.3 cm). The nozzle tip ordinarily carries a series of diagonal grooves, beads or stepped shoulders as guides for diagonal cut-off of the nozzle tip. Where the nozzle has no shoulder, the width between side seams is typically selected to be the nozzle diameter at from about ½″ to about 1″ from the tip toward the cartridge tube body.

[0019] By virtue of the fact that the selected plastic of the sleeve is somewhat stretchable, the side seams need not be tapered, but may be parallel, since as the sleeve is pulled down over the nozzle, it configures tightly and completely around the nozzle from just below the tapered tip to the base of the shank adjoining the cartridge or squeeze tube top thus providing an excellent hermetic seal. Thus, the preferred minimum stretchability of the film is the ratio of the nozzle base width to the width of the nozzle at the top of the seal area, typically at the tip taper; for a consumer caulk cartridge this is about 1.25 to about 1.5, and can range up to about 3.5 to about 5 for commercial cartridges. The greater the area of contact, the better the seal. The pocket length is preferably longer than the cut nozzle to provide a small head space at the top of the pocket for any excess sealant or mastic, which may be extruded from the open tube end. This also provides a visual indicator of the condition of the tube contents. As long as the composition within that head space remains soft and pliable, it indicates that the contents of the tube have not dried out or set from the nozzle end. It should be understood that the tube could dry out from the plunger end in the event of a defective piston seal.

[0020] The side seams should be of sufficient strength and/or width, and the film of sufficient thickness, strength and stretchability to ensure that the sleeve does not split open when it is pulled down over the nozzle of the dispenser cartridge and retain its integrity over the life of the sealing sleeve, up to a year or more. Typically, a seam width on the order of {fraction (1/16)}″-{fraction (3/16)}″ (2-6 mm) is adequate, but it may be any suitable width depending on its integrity and strength. Additional plastic material may be provided outwardly of one or more of the seams, preferably both sides, to permit ease of handling, and may be configured to provide graspable wings or flanges for mounting and removing the sleeve. Further, a V-shaped or semi-circular shaped notch (presently preferred) or depending flap may be provided at the opening end of the sleeve in one or both sheets of plastic to permit ease of opening the sleeve pouch to permit insertion of the nozzle. A plurality of sleeves may be provided in a strip, preferably with each separable from the other by a line of perforations so that each sleeve can be torn from the strip as needed.

[0021] As to packaging, the sleeves may be packaged in a plastic bag with a header card for sale as sealing sleeves, or an individual one or plurality of sleeves may be packaged with each dispenser cartridge or squeeze tube. In this latter embodiment, a pressure-sensitive glue may be applied to one face of the side wings or flanges of the sleeve, and the sleeve simply adhered to the side wall of the dispenser cartridge or tube. In another packaging embodiment, one or more sleeves can be packaged in a small bag or pouch along with instructions, which pouch is then adhered to the dispenser cartridge or squeeze tube. In still another embodiment, at least one sleeve can be slipped over the uncut nozzle of each fresh tube, and secured thereto by pressure-sensitive glue, a tether, rubber band, paper or plastic cuff, or a conventional cap. As an alternate of this embodiment, a roll of sleeves is wrapped around the nozzle and secured by rubber band or cuff.

[0022] In actual testing, a polyolefin plastic sleeve having a thickness on the order of 4 mils maintains the freshness and prevents drying out of water-based acrylic caulk in excess of nine months. The sleeve is easily removed by hand by simply slipping it off the nozzle. The sleeve may be reused, and due to its conformable nature, on reuse, provides an excellent seal along its length. Any sealant or mastic in the headspace of a removed sleeve can be prevented from drying out by partly flattening the sleeve, beginning at the open end. That is not possible with a rigid cap, and thus the inventive seal provides still another significant and unexpected advantage over conventional cap-type closures.

[0023] In still another embodiment, a rigid cap can be provided with an internal sleeve of this invention, the cap providing some additional ease of fitting the sleeve over the cut nozzle and removal. Also, caps are familiar to caulk tube users.

[0024] The invention thus solves the long felt need of substantially retarding or preventing hardening of residual sealant and mastic composition in dispenser cartridges and tubes, while conserving materials and being environmentally friendly. It also results in economies for the users, and adds both real and perceived value for the consumer to those caulk, sealant and mastic cartridge and squeeze tube products which offer the inventive sleeves as a solution to the well-known wastage as occurs by use of conventional caps.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The invention as described in more detail with reference to the drawings in which:

[0026] FIG. 1 is an isometric view of an inventive sleeve seal fitted on dispenser nozzles to preserve the remaining composition,

[0027] FIG. 1A showing the inventive sleeve mounted on the cut nozzle of a tubular dispenser cartridge, and

[0028] FIG. 1B showing in exploded view how a sleeve of the invention may be packaged for delivery with a squeeze tube having a conventional cap;

[0029] FIG. 2 is an isometric view of a strip of sleeves of the invention showing them separable from each other along transverse perforations;

[0030] FIG. 3 is an isometric view of an alternative embodiment of a strip of tubular sleeves of the invention separable along transverse perforation lines;

[0031] FIG. 4 is an isometric view of a plurality of the inventive sleeve seals removably adhered to the sidewall of a dispenser cartridge in its ready-for-sale condition;

[0032] FIG. 5 is an isometric view showing a packet of inventive sleeves packaged in a pouch adhesively secured to the outside wall of a dispenser cartridge (lower half of the figure), and also showing a sleeve mounted on an uncut nozzle in place of a cap, in the cartridge's ready for sale condition (upper half of the figure);

[0033] FIG. 6 is an isometric view of an alternative embodiment of an inventive sleeve seal having a tether, which fits over the cylindrical body of a dispenser cartridge;

[0034] FIG. 7 is a side elevation, in part broken away, showing an inventive sleeve seal secured in a rigid plastic cap;

[0035] FIG. 8 is an isometric view of a strip of inventive sleeve seals packaged for after-market sale in a bag/header card package;

[0036] FIG. 9 is a plan view of another embodiment of a strip of inventive sleeve seals in which the seal lines are tapered;

[0037] FIG. 10 is a plan view of still another embodiment of a strip of inventive sleeve seals in which the plastic strip is folded parallel to its long axis, and the two seams are oriented normal to each other, and the sleeves are separable along perfed lines;

[0038] FIG. 11 is an isometric view showing a plurality of sleeves mounted on and wrapped around the nozzle of a dispenser cartridge and secured thereto with a paper sleeve or shrink-wrap-type collar; and

[0039] FIG. 12 is an isometric view of a window glazing type cartridge having a nozzle that is generally square in cross-section and employs a sleeve seal of the invention.

DETAILED DESCRIPTION INCLUDING THE BEST MODE OF CARRYING OUT THE INVENTION

[0040] The following detailed description illustrates the invention by way of example, not by way of limitation of the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is presently believed to be the best modes of carrying out the invention.

[0041] In this regard, the invention is illustrated in the several figures, and is of sufficient complexity that the many parts, interrelationships, and sub-combinations thereof simply cannot be fully illustrated in a single patent-type drawing. For clarity and conciseness, several of the drawings show in schematic, or omit, parts that are not essential in that drawing to a description of a particular feature, aspect or principle of the invention being disclosed. Thus, the best mode embodiment of one feature may be shown in one drawing, and the best mode of another feature will be called out in another drawing.

[0042] All publications, patents and applications cited in this specification are herein incorporated by reference as if each individual publication, patent or application had been expressly stated to be incorporated by reference.

[0043] FIG. 1 illustrates two principal variations of the closure sleeve device 10 of this invention, FIG. 1A illustrating a first embodiment of the sleeve mounted on a nozzle 12 of a conventional dispenser cartridge 14, and FIG. 1B illustrating a second embodiment of the sleeve shown in an exploded view in position being mounted on or removed from the nozzle 12 of a conventional manually squeezable tube, and the optional use thereover of a conventional cap.

[0044] In FIG. 1A, the tip of nozzle 12 has been cut diagonally 13, as is usual. The dispenser cartridge 14 is shown as having been partially used, the slidable internal diaphragm 16 shown in dashed lines as having been advanced well up the cylindrical cartridge body by the plunger of a caulk gun (not shown), with the residual composition 20 occupying the volume between the diaphragm and the nozzle. As is usual in use, the nozzle bore is filled with the composition and some portion of extruded composition 22 is shown in the head space 58 in the sleeve between the sleeve top end 24 and the nozzle cut end 13. Note the length of the sleeve L (see FIG. 2) is preferably selected to be somewhat longer than the nozzle to provide the head space. The bottom end 48 of the sleeve may be notched 24a or scalloped to provide a flap 24b (see FIG. 2) to permit ease of opening the sleeve pocket 32 into which the nozzle fits through pocket opening 28 (FIGS. 1B, 3). One portion of the wall of the sleeve may have one or more flaps, 24b, adjacent the opening, and another portion may be straight cut or notched to provide means to open the sleeve pocket (see FIG. 2, right end).

[0045] In this embodiment, the sleeve is formed of two sheets of plastic 42, 44, preferably clear, transparent or translucent plastic film, e.g., polyolefin of suitable thickness, which sheets have been sealed together along two spaced, substantially parallel lines 34a, 34b, with the nozzle pocket 32 being formed there between. Outboard of the seal lines are extensions, flanges or wings of plastic 50, 52, that may be grasped to pull or push the sleeve onto the nozzle.

[0046] It is an important feature of the invention that the seal lines are spaced apart a distance A (see FIG. 2) approximately the width of the nozzle (cross-section diameter) at the point along its length where the seal is to begin, i.e., at point S1 down the nozzle 12 from the cut end 13. The maximum is that the pouch seams should not be spaced apart substantially wider than the nozzle at its juncture with the cartridge or tube delivery end 56, i.e., point S2. It is preferred that seal spacing be less than the midpoint diameter S3, so that when the sleeve is opened, the inner circumference of the sleeve plastic forming the pocket 32 is slightly less than the circumference of the nozzle medial of its ends, preferably the sleeve side seam spacing is substantially equal to or slightly more than the diameter of the nozzle adjacent the juncture of the tip taper 60 to the nozzle body (at approximately S1), and no more than the circumference at approximately the nozzle midpoint (point S3). This dimensioning insures a relatively long sealing contact area S (see FIG. 1A) between the sleeve and the nozzle. This provides the necessary hermetic seal of the inventive sealing sleeve to retain the remaining unused sealant or mastic composition in a nearly original condition for extended periods of storage, in excess of 9 months in actual tests of a water-based acrylic latex caulk containing silicone.

[0047] The above generally refers to nozzles that are round in cross-section. For square cross-section nozzles, the sleeve tube can be constructed to have a square cross-section, or appropriately dimensioned so that the plastic stretches to conform tightly to the nozzle cross-section, as shown in FIG. 12.

[0048] The flexible and slightly stretchable property of the plastic, e.g., polyolefin polyvinylidene chloride copolymer, or equivalent plastic film or sheeting, provides the necessary conformational property to provide the hermetic seal. That is, the sleeve film stretches sufficiently to fit tightly on the nozzle without relaxing or slipping off by creep. Likewise, the film does not thin so much that it becomes easily permeable by oxygen (inwardly) or by solvent (outwardly from the composition). Non-thinning is maintained at the critical location, the head space, by the seam lines being spaced at the upper, tapering end of the nozzle substantially equal to or wider than the juncture of the taper 60 to the nozzle, so that there is little stress on the sleeve plastic in the head space area 58, being defined between the upper end of the sleeve 24 and the nozzle opening 13.

[0049] Of course, one skilled in this art, following the principles taught herein, can adjust the length of the sleeve to suit a particular nozzle length, and by doing so control the amount of head space. While a substantial head space serves the useful purpose of providing a visual indicator of the condition of the residual contents (and its color), the sleeve plastic being preferably clear, transparent or translucent in that area, the head space can be reduced to no more than a “window” over the opening of the nozzle in order to reduce the potential surface area for vapor and oxygen permeation. That is the preferred embodiment for the square cross-section nozzles of window glazing cartridges.

[0050] FIG. 1B shows in exploded view an inventive sealing sleeve 10 insertable on the nozzle 12 of a squeeze tube 15. As shown, the nozzle has not been cut, so the illustration represents one mode of packaging and delivery of the sleeve to the consumer as an OEM component. An optional standard cap can be provided with one or more internal ridges or grooves (not shown), which snap fit over complementary grooves or ridges 66 on the nozzle 12. The sleeve plastic is sufficiently thin that it does not interfere with the snap fit action of presently-dimensioned caps and nozzles, or the grooves and ribs can be easily re-dimensioned to permit good retention of the cap on the nozzle while trapping the sleeve for delivery to the consumer. The sleeve can be used with or without a cap. The sleeve can be entirely separable from the cap or sealed or glued to it (FIG. 7) or tethered to the caulk tube (FIG. 6).

[0051] FIG. 2 shows a strip 30 of a plurality of inventive sealing sleeves 10a, 10b, . . . 10n of the type shown in FIG. 1A. The inventive sleeve seals are formed from a single sheet of plastic folded in half parallel to its long axis to form a double-layered strip that is alternately heat sealed and perfed to form a plurality of individual separable sleeves in the strip. The seam lines 34a, 34b are spaced apart and generally parallel (although they may be tapered inwardly from bottom to top) to form nozzle-receiving pouches 32a, 32b, . . . 32n. The perf lines 36a, 36b, . . . 36n cut through both sheets so the individual sleeves are easily torn off the strip. As shown, the perf lines 36 are spaced from the adjacent seam lines 34b to form opposed wings or flaps 50, 52. Sleeve 10a includes a notch 24d, while sleeve 10b includes one or more depending flaps, which function to assist in opening the pocket for insertion of the nozzle therein. Sleeve 10n is strait cut on one side and has a flap 24b on the other. The length L is as described above, being on the order of the length of the nozzle 12 (FIG. 1), is sufficiently longer than the nozzle to provide a suitable head space. The width between the seams 34a, 34b are also as described above, typically the diameter of the nozzle at the shoulder juncture of the tapered tip 60 with the nozzle shank 12 (see FIG. 1).

[0052] FIG. 3 is an isometric view of an alternative embodiment of the invention comprising a strip 30 of thin plastic tubing 74 which has a series of transverse seams 34a, 34b, . . .34n, and perf lines 36a, 36b . . . 36n adjacent to, or spaced from the seams, to define individual sleeves 10a, 10b . . . 10n. The tube width is essentially the diameter A as defined above (see FIG. 2). The distance between the seam 34 and the perf line 36 may range from 0 to about ¾″ to provide a flange to assist in handling.

[0053] FIG. 4 illustrates one manner of packaging the inventive seal sleeves. In this embodiment a plurality of the sleeves of FIGS. 1 and 2 are removably secured to the outer face of a dispenser cartridge by means of suitable pressure-sensitive glue 64 applied to the cartridge, the cartridge-facing side of wings 50, 52 or the entire backside of the sleeve to secure the sleeves to the cartridge during manufacture, distribution and sale handling. The sleeves are peeled off the side of the cartridge one at a time and separated along the perf lines 36 as before. As seen, a set of three sleeves is packaged on the tube, and the third, 10c, is shown as peeled off, ready for separation from the strip. This figure also shows the tip taper 60 at the upper end of the nozzle shank, and a series of angled grooves or shoulders 62 as tip cutting guides.

[0054] FIG. 5 illustrates another embodiment of the invention in which a strip 30 of inventive sleeve seals, such as strip 30 of FIGS. 2, 3, 6, 9 or 10 are packaged in pouch 78, which is adhesively, but removably secured to the outer wall of the cartridge 14. the pouch 78 may be recloseable, such as by a press fit rib and groove closure strip. This figure also illustrates another embodiment of the sleeve seal of FIGS. 1-4 in which the wings 50, 52 are lobed 68a, 68b adjacent the bottom 46 of the sleeve to assist in handling. The lobes may be cut out of both sheets of plastic 42, 44. The wings may be sealed together, or the wings may be replaced by a thicker sheet of plastic, such as a 5-10 mil thickness piece of plastic, or such a thick sheet of plastic may be laminated between the wing sheets.

[0055] FIG. 6 illustrates an embodiment in which the two side seams 34a, 34b are tapered, generally with a taper corresponding to the taper of the nozzle, and having a transverse seam 34c across the top, instead of a fold. From one wing 50 extends a tether 70 terminating in a loop 72 that fits over the cartridge or squeeze tube body. Alternately, the loop may be omitted and a portion 79 of the tether may have pressure sensitive glue on one side to attach the tether to the cartridge tube body or end face.

[0056] FIG. 7 illustrates a conventional plastic cap 90 in which is fitted a tubular type sleeve of FIG. 3, which is secured to the open end of the cap by tabs 92a, 92b which are glued or heat sealed to the cap rim. The tabs may be the flaps 24b (see FIG. 2). The sleeve is shown open at 28.

[0057] FIG. 8 shows an alternative after-market packaging embodiment 80 in which a strip of sleeves 30 is packaged in bag 82 stapled at 84 to a header card 86, which may include the standard rod hanger aperture 88.

[0058] FIG. 9 shows a strip of tapered sleeves of FIG. 6 that are oriented in opposed, alternating (dove-tailed) configuration. The seams 34 and perfs are as described above. In this embodiment, the sleeves are preferably prepared from a large tube having a diameter L, and the alternating opposed side margins 46, 46′ of the tube are die cut to form the respective pocket openings 28a, 28b.

[0059] FIG. 10 shows still another embodiment in which the strip of plastic 30 is folded down the longitudinal axis, and seams 34 and 98 are oriented normally to form the pockets 32a, 32b, 32c . . . 32n. As before, spaced perf lines 36a, 36b . . .36n permit separation of individual sleeves 10a, 10b, 10c . . . 10n from the strip 30. The pockets 32 are formed between side fold 54 and longitudinal seam 34, the top is formed by seam 98 which intersects seam 34. In this embodiment, only one wing 50a, b, c is formed, but by providing another seam 34 (not shown) spaced inwardly from edge 54, an opposed wing can be provided. As noted, the longitudinal seam 34 may be continuous, as shown at 34b, 34c, or discontinuous, as shown by the gap in what becomes top tab 100b of pocket 32b. The perfs 56 may be adjacent the transverse seams 98, or spaced therefrom to provide top tabs 100a, b, c which assist in handling. The perf lines 36a, 36b need not be strait; they may be curved to provide flaps similar to 24a, b in FIG. 2.

[0060] FIG. 11 is an isometric view of still another embodiment of the inventive sleeve seals packaged as a strip 3 rolled around the nozzle 12 of a cartridge 14, and secured with a collar or cuff 94, which alternately may be a rubber band, shrink-wrap band, tape or twist-tie.

[0061] FIG. 12 shows a larger diameter sleeve 10 sized and adapted to fit over a window glazing nozzle 12 which is square in cross-section. Note the enlarged head space 58 to accommodate the smoothing tab 17. Note the wings 50, 52 are oriented at the corners of the nozzle.

[0062] Industrial Applicability:

[0063] It is clear that the sealing sleeve of the invention has important applicability to a wide variety of sealant and mastic compositions for both dispensing cartridges and squeezable tubes. The economic advantages of the invention to the consumer, and the ultimate reduction in disposal of hundreds of millions of cartridges and squeeze tubes annually, many of which retain substantial quantities of sealant and mastic, represent a very substantial reduction in the wastage of valuable resources, and result in reduction in the cost of environmental remediation. Accordingly, it is evident that the sealing sleeve of the invention will have wide industrial applicability.

[0064] It should be understood that various modifications within the scope of this invention can be made by one of ordinary skill in the art without departing from the spirit thereof. For example, the sealing sleeves of the invention can be color coded by use of colored plastic or overprinting. I therefore wish this invention to be defined by the scope of the appended claims as broadly as the prior art will permit, and in view of the specification if need be, including equivalents thereof.

Claims

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.