Abstract:
Disclosed herein are strips for dispensing insecticidal actives and fragrances. The strips are stored in vapor impermeable pouches where a part of the pouch is pre-interlocked with the strip. A strip can be torn away from most of the pouch using another part of the pouch as a handling portion. Also disclosed are methods of making such assemblies, strips obtained from such assemblies, and methods of using such strips to control flying insects.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     The present invention relates to devices for dispensing volatiles into the air. It appears to be particularly well suited for controlling flying insects that may be present in building rooms. 
     The term “volatile medium” is used below to refer to a readily evaporable material having an active ingredient, such as (but not limited to) fragrances, disinfectants, deodorizers and especially insect control actives. The term “active” in this context refers to a material to be released in order to achieve a desired effect (e.g., an insect control active may kill and/or repel insects). 
     There are a number of examples in the prior art of substrates coated or impregnated with substances. Some of these have previously been stored in a sealed pouch until use. The pouch was torn open at its top edge and the user reached into the pouch to remove the strip. This either required the use of a special tool (e.g. a tweezers) or led to the consumer coming into contact with the substrate. 
     This could be a safety concern for certain insecticides, thus limiting the choice of actives. Even where contact with human skin was not a safety concern, it could be perceived that way by the consumer. 
     One dispenser design for use with volatile media was disclosed in U.S. Pat. No. 6,012,643. The disclosure of this patent, and of all other publications referred to herein, are 
     One dispenser design for use with volatile media was disclosed in U.S. Pat. No. 6,012,643. The disclosure of this patent, and of all other publications referred to herein, are incorporated by reference as if fully set forth herein. This patent disclosed a hangable device for dispensing into the air fragrance that was impregnated into a substrate. The substrate was initially enclosed in a type of pouch that had multiple tear-away segments that were removed as needed to meter the release of the fragrance. 
     While this product extends the useful life of volatile strips, it exposes only a small segment of the strip at a time (which may be less desirable for insecticidal use). Moreover, it requires multiple contacts with the structure. 
     U.S. Pat. No. 968,237 discloses a strip which acts as a fly catcher. It is coated with a gummy bait substance so as to both bait and trap insects to the strip. It is not designed to emit a volatile as an active, requires the use of an awkward opening mechanism, and in any event leaves the lower portion of its main pouch in place during use (thereby presenting a somewhat ugly product). 
     Thus, there is a need for a further improved dispensing strip. 
     BRIEF SUMMARY OF THE INVENTION 
     In one aspect the invention provides a dispensing strip assembly. It has a vapor impermeable pouch with opposite sides, and a substrate in the form of a strip inside the pouch which is impregnated with a volatile medium. For purposes of this application “impregnated” can mean surface coated or partially or totally permeated with the volatile medium. The opposite sides of the pouch are interlocked with an end of the strip. 
     In preferred forms, the strip has an opening adjacent its upper end and the pouch is interlocked with the strip through the opening. Also, the pouch has tear points formed at opposed lateral edges below the opening in the strip. When the strip substrate is impregnated with an insect control active, the device can be used to repel and/or kill insects. When the strip substrate is impregnated with a fragrance or perfume, the device can be used as an air freshener, for example, in a closet or automobile. 
     In another aspect the invention provides a hangable strip for dispensing a volatile medium. There is a strip impregnated with a volatile medium, the strip having adjacent its end an opening. There are also opposite sides of a tear away portion of a vapor impermeable pouch that previously held the strip. They are joined together through the opening in the strip such that the end of the strip is interlocked with the pouch tear away portion. There is also a hanger attached to the strip through the pouch tear away portion. 
     It will be appreciated from the description below that one can tear the outer pouch of such a dispensing strip assembly at the tear points and then grip and pull firmly up at the upper end of the pouch. This will cause the pouch to tear essentially horizontally below the interlock, albeit without tearing the strip itself. The upper portion of the pouch remains with the strip as a type of handle. 
     It should be appreciated that the size of the tear notches can be varied depending on the selection of tensile strength and tensile resistance of the substrate and outer pouch. For this purpose, notch sensitive plastic barrier films are preferred for the outer pouch. 
     One can use the handle to pull out the strip from the bottom part of the pouch. Gravity (sometimes with the assist of a little shaking) will then cause the strip to unfold into a generally vertical strip. A hanger attached to the “handle” prior to tearing open the pouch can then be used to hang the dispensing strip from a closet bar, wall nail, fan housing, or other room structure. 
     In yet another aspect the invention provides a method of forming such a dispensing strip assembly. One forms a hole in an end of a strip, notches a lateral edge of a pocket to create a tear point, and inserts the strip into the pocket so that a top end of the strip is positioned above the tear point. 
     One then positions a volatile medium in the pocket so as to impregnate the strip therewith, and seals a top end of the pocket to form a vapor impermeable pouch around the impregnated strip and also so that opposite sides of the pouch are joined together through the strip hole. This interlocks an end of the strip to an end of the pouch. 
     In yet another form the invention provides methods for controlling flying insects in a room by hanging such a strip in the room. 
     The present invention permits the long-term stable storage (e.g. at retail stores) of such products. When the product is to be used, most of the pouch may be discarded to expose the strip. Importantly, contact between the hand and active is avoided. 
     By interlocking one end of the strip to an end of the pouch, one can design an outer pouch that will break cleanly before the strip does. Further, this helps assure that the strip can be completely pulled out of the pouch (notwithstanding being in folded form) without the strip pulling away from the “handle”. 
     The present invention is also well suited for production by automated production techniques. Further, it can be produced at extremely low cost. 
     These and still other advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which from a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front elevational view of a strip for use in connection with the present invention; 
     FIG. 2 is frontal, slightly left, perspective view of the strip of FIG. 1, albeit shown with the lower end of the strip folded up; 
     FIG. 3 is a front elevational view (with the pouch shown in section) of the strip of FIG. 2 being inserted into a vapor impermeable pouch; 
     FIG. 4 is a view similar to FIG. 3, albeit with the strip fully inserted and active being shown as being added; 
     FIG. 5 is a view similar to FIG. 4, albeit at a later stage of manufacture; 
     FIG. 6 is a view similar to FIG. 5, albeit with a hanger inserted in a top opening and the pouch in the process of being torn open; 
     FIG. 7 shows the dispensing strip in various stages of unfolding; 
     FIG. 8 depicts a film web that is longitudinally folded; and 
     FIG. 9 depicts how the FIG. 8 film web can be processed to form dispensing assemblies of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1 and 2, the dispensing assembly includes a substrate  10  that is in strip form. It is preferably a flat, somewhat flexible, rectangular card of vegetable fiber, such as wood pulp/paper. However, it could alternatively be made from numerous other synthetic and/or natural materials. For example, in one embodiment we used a non-woven polymer for the strip. This was very absorbent but led to slower release. 
     Other suitable strip substrates could be wettable films, microporous films, cloths, and other substrates that will release the volatile. Note that the variety of suitable materials is increased because the strip does not need to be compatible to the pouch material for heat sealing. 
     The strip  10  preferably has a pair of through holes  12  and  14  that are spaced apart at a top end  16 . If desired, only one such hole need be used. A bottom end  18  of the strip can be folded up upon itself for storage (see FIG.  2 ). 
     Referring next to FIG. 3, the folded strip substrate  10  is stored in a vapor impermeable pouch  20 , preferably made of a heat sealable material, such as a plastic. One such suitable material is BAREX® brand plastic which is available from BP Amoco. Other suitable plastics for the outside pouch include, without limitation, polyesters/copolyesters, nylon, polypropylene, and various laminations of the preceding materials also including paper, aluminum foil and other sealant materials. 
     As best seen in FIG. 4, the pouch  20  begins in the form of an upwardly open pocket which has opposite front  22  and back  24  sides. There can be a common bottom  26 , and the sides can be joined at lateral edges  28  and  30  by a suitable sealant, such as an adhesive, or sealing process, such as heat sealing or ultrasonic welding. The bottom does not need further sealing if it is a fold line formed of a sheet that is folded back on itself (see FIG.  8 ). If two separate pieces of plastic are used, the bottom can also be sealed. 
     The lateral edges  28  and  30  are preferably formed with notches  32  and  34 , respectively, at the same distance from a top edge  36  of the pouch  20 . This places them below the openings  12  and  14  in the strip substrate  10  when it disposed in the pouch  20 . The notches  32  and  34  provide tear-points facilitating tearing the pouch  20  from the lateral edges. 
     With the strip  10  disposed within the pouch  20 , a suitable volatile medium (shown by arrows  37 ) is dispensed in liquid form into the pocket to impregnate the strip substrate  10 . In one embodiment, an insect repellant is added as the active. Pryethrum and pyrethroid type materials commonly now used in mosquito coils are likely to be the most useful for this purpose. Especially preferred pyrethroids (from the standpoint of expense, activity or both vis-a-vis mosquitos) are d-allethrin, allethrin, prallethrin, bioalletherin, s-bioalletherin, esbiol, dichlorvos, transfluthrin, pyrethrum and combinations thereof. Other insect control actives can be used, such as the repellants DEET, citronella, lemon grass oil, lavender oil, cinnamon oil, neem oil, clove oil, sandalwood oil and geraniol as well as the insect growth regulators, such as hydroprene. 
     The actives will typically be carried in a hydrocarbon solvent such as Isopar or other known solvents that have previously been used to dispense volatile actives from substrates. 
     The dispensing strips of the present invention can also be used as a disinfectant/fragrancer/deodorizer. A wide variety of such volatiles are well known in the art. The dispensing strip can also dispense multiple actives to, for example, both disinfect and freshen the air. 
     To form the FIG. 5 structure from the FIG. 4 structure, one first cuts off triangle pieces from the top (for ornamental reasons) to crate corners  44  and  46 . Then, a tear-away top end  40  (above the notches  32  and  34 ) of the pouch  20  is hermetically heat sealed so that the front  22  and back  24  sides are joined together at the top edge  36 . Importantly, the heat sealing also causes the sides  22  and  24  to be joined together through the openings  12  and  14 . This interlocks the strip substrate  10  to the tear-away top end  40  of the pouch  20 . 
     One can also provide an additional hole  48  for receiving a hanger  50 . This then results in the product that can be stored on a long-term basis. 
     Referring next to FIGS. 6 and 7, the top end  40  of the pouch  20  can be torn away by hand, using the notches  32  and  34  to help start the (and to define the path of) ripping. Once the tear has been made, the strip can be pulled out from a handle portion  38 . 
     The strip  10  will then automatically unfold due to gravity and/or due to a little shaking. See generally FIG.  7 . The device can then be hung via hanger  50 . 
     FIG. 9 depicts a preferred production line for forming the dispensing strips. The FIG. 8 folded materials is fed from a web starting at the left. Progressing then left to right, the sides of the pouch are heat sealed, the strip is inserted, the active is added, the upper portion of the pouch is heat sealed, a hanger hole is provided and corners of the upper tab are cut for aesthetics, and each dispensing strip is severed from the other. It will therefore be appreciated that this technology is suitable for high speed automation. 
     It should be appreciated that other embodiments of the dispenser not mentioned above are within the scope of the invention. For example, the strip need not be folded at all within the pouch. Also, the form of the interlock between the pouch and strip need not be both sides of the pouch sealed together through a through hole. Rather, the interlocking may be achieved through selection of strip and pouch materials that seal to each other. Accordingly, the claims should be referenced in order to determine the full scope of the invention. 
     INDUSTRIAL APPLICABILITY 
     The invention provides a hangable strip for dispensing a volatile active. The strip can be stored in a pouch which can be opened in a way where a user is not required to contact the volatile material in order to activate the system.