MXPA98007308A - Repellent article of insects that provides low container humidity - Google Patents

Abstract

The present invention relates to: providing a disposable, portable article for repelling insects. The article includes a fibrous substrate that can be impregnated with the insect repellent. In one embodiment, the intermediate fibrous substrate is provided to the porous cover and to a barrier layer, and comprises fibers having external capillary channels. The porous cover may comprise a plastic film with openings having tapered openings. The insect repellent may be contained within a breakable packet, such that when the breakable packet is broken, the insect repellent is directed through the fibrous substrate for release through the apertured film.

Description

say.

REPELLENT ARTICLE OF INSECTS THAT PROVIDES LOW CONTACT HUMIDITY FIELD OF THE INVENTION The present invention relates to an article for providing release of a volatile substance and more particularly to a disposable portable article for providing release of the insect repellent from a release surface having the low release surface contact humidity BACKGROUND OF THE INVENTION Bug or insect repellents for personal use have been historically delivered in a number of different ways for example this can be sprayed or impregnated on the skin of a user, sprayed in the immediate environment and / or sprayed on the garments of One The bug repellent solution is typically volatile in such a way that vapors are released which repel bugs away from one's body Absorbent substrates saturated with volatile bug repellent solutions made in the form of patches have been available for application to clothing. Typically, a patch containing a volatile solution must be contained in a package which avoids evaporation of the solution before patch application United States Patent Application No. 08/369 068 Package to contain and apply a bug repellant patch filed on January 5, 1995 on behalf of Cook and others discloses a package to contain a patch impregnated with repellent of bugs The disclosed package allows a user to apply the patch to a target surface without making contact with the patch These patches may have a barrier matepal between the substrate and a target surface, such as a user's clothing. The barrier material may allow larger volumes of volatile solution to be used to provide longer-lasting protection against insects. As it increases the amount of the solution, however it is more likely that some of the solution may drain off the substrate in the liquid form and possibly stain an article such as the user's clothing or skin. Consequently the amount of the solution that can be released in the form of steam in a given amount of time from a given surface area of the article, and for a given amount of liquid initially provided on the article is limited by the desire to avoid staining an article by draining It is therefore an object of the present invention to provide a disposable, portable p to provide the release of a volatile liquid material, such as an insect repellent material, liquid Another object of the present invention is to provide a disposable, portable article to provide the release of a liquid volatile material while minimizing the amount of liquid material which is transferred to the wearer's clothing or skin when the article is applied to a target surface, such as by pressure. Another object of the present invention is to provide a disposable, portable article to provide for the release of a liquid volatile material from a release surface of the article where the release surface has a low contact humidity, under a pre-eschat load BRIEF DESCRIPTION OF THE INVENTION The present invention comprises a disposable portable article, for providing the release of a volatile liquid matepal, such as an insect repellent material, from a release surface of the article. The article includes a substrate impregnated with the volatile liquid material. Under a pre-skeleton charge the release surface of the article has a contact humidity of less than about 10 g, more preferably less than about 50 g, and even more preferably less than about 25 g Under the pre-skeleton charge, the release surface may have a normalized contact humidity of less than about 100 mg per gram, more preferably less than about 50 mg per gram, and even more preferably less than 25 mg per gram, wherein the standardized contact humidity is the contact humidity divided by the total weight of the liquid material impregnating the substrate In one embodiment, the article can provide a normalized release rate of about 0 25, more preferably at least about 0 0, and even more preferably at least 0 50 In one embodiment of the present invention, the article comprises a barrier layer, a porous layer of cover and a substrate impregnated with a volatile liquid matepal The release surface may comprise an outward facing surface of the porous cover layer The article may also comprise an adhesive fastener for securing the article to a target surface, such as a garment of the user The release surface of the porous cover layer can have an open area ratio of at least about 20%, and most preferably at least about 30%, to provide effective release of the vapors from the liquid volatile material. In one embodiment, the ratio of the open area may be greater than about 50%. cover may have a caliper of at least about 0015 inches, in a mode at least 0 050 inches approximately The disposable article may have a maximum caliper of not more than about 10 cm, preferably less than about 5 ml, and more preferably less than 30 ml as measured with a confining load of 322 g applied by a loading area of 0 95. inches in diameter The article may have a total weight of not more than about 40 grams (measured as the article is applied to the target surface and a stiffness not greater than about 0 5 pounds inch, and more preferably not greater than 0 1 pounds / inch to provide comfortable compliance with a variety of target surfaces The substrate may be impregnated with a liquid volatile material, comprising an insect repellent. In one embodiment, the substrate is impregnated with no more than about 2 09 g of the liquid material, and the weight ratio of liquid volatile matepal, to the weight of the substrate is at least about 2 0 BRIEF DESCRIPTION OF THE DRAWINGS While the disclosure terminates with the claims singling out and claiming differently from the present invention, it is believed that the invention will be better understood from the following description in combination with the accompanying drawings in which Figure 1 is a cross sectional view of an embodiment of the present invention wherein the article is enclosed in a sealed package. Figure 2 is a top plan view of the article of Figure 1, with the sealed package removed and the porous cover layer partially cut out. to show a substrate that has a relatively lower density region extending between regions with relatively higher density Figure 3 is an enlarged cross-sectional view of a portion of the article of Figure 1, showing a porous cover layer having generally tapered apertures. Figure 4 is a cross-sectional illustration of a capillary channel fiber having a generally I-shaped cross-section Figure 5 is a cross-sectional view of an alternate embodiment of the present invention having a breakable container containing the volatile liquid insect repellent placed intermediate to the porous cover layer and to the layer Figure 6 is a plan view of an alternate embodiment of the present invention having discrete spacers extending from the substrate to provide a release surface comprising a continuous network opening. Figure 7 is a cross-sectional view of the article of Figure 6 taken along lines 7-7 and showing the discrete separators Fig. 8 is an alternate embodiment of the present invention having a substrate formed of a woven polyolefin fiber yarn and a breakable container connected to the substrate through a fluid conduit. cross section of an alternate embodiment of the present invention wherein the substrate has a contoured surface and wherein the barrier layer is applied to the raised portions of the contoured surface to provide a release surface that is integral with the substrate. it is an alternate embodiment of the present invention wherein a separable supeporous sheet film is thermally sealed to at least the portions of the barrier layer to prevent evaporation of the liquid material before the article is used.

DETAILED DESCRIPTION OF THE INVENTION Figures 1 and 2 show an embodiment of a disposable, portable article 20, according to the present invention for providing the release of volatile material comprising one or more components. In article 20 it comprises a release surface and a substrate impregnated as a liquid volatile matepal In one embodiment, article 20 comprises a substrate impregnated with a liquid volatile material, and the released material comprises an insect repellent. By the term "disposable", it is implied that the article 20 is intended to be discarded after a single use. By the term "portable", it is understood that article 20 may conveniently and comfortably be carried in a bag, pocket, or hand bag. By the term "liquid volatile material", it is implied that a liquid matepal comprising a component having a vapor pressure of at least about 0 001 mm Hg at 50 ° C. In the embodiment shown in Figures 1-2, the article 20 comprises a barrier layer 30, and a porous cover layer 40 having an outwardly releasing surface 44 and a substrate 50 impregnated with a liquid volatile material. material with which the substrate 50 is impregnated, preferably comprises a material effective to repel insects The release surface of the article has a contact humidity of at least about 0 100 g (100 mg) under a pre-skeleton charge as decipher more completely forward. The article 20 may also include a gripper 60, such as a pressure sensitive adhesive. The fastener 60 may be used to hold the article 20 on a target surface, such as a garment of the wearer. Article 20 can be sealed in the wrapper 22 to prevent evaporation of the insect repellent before the article 20 is used- In Figure 2 the wrapper 22 is omitted to show the internal construction of article 20. Referring to the components of article 20, in greater detail, the layer barrier 30 is generally impermeable to liquid volatile substance- Barrier layer 30 prevents liquid volatile substance in substrate 50 from contacting the target surface on which article 20 is held- In one embodiment, the barrier layer 30 comprises a flexible film, such as a polymeric film, a flexible sheet, or a composite material such as a sheet / flexible film laminate. By "flexible", it is implied that the barrier 30 is compliant and easily shapes and shapes. contours of a variety of target surfaces, such as clothing. A suitable barrier layer 30 may comprise a woven or non-woven material or a polymeric film such as a thermoplastic film of polyethylene or polypropylene. A suitable thermoplastic film is a polyethylene film having a thickness of between about 0-012 mm to about 0. 051 mm. Suitable films are manufactured by Clopay Corporation of Cincinnati, Ohio, under the designation P18-0401 and by Ethyl Corp., of Terre Haute, Indiana, under the designation XP-39385. Alternatively, the barrier layer 30 may comprise a sheet laminate and polymeric film, such as sheet / film laminate of type 2077 manufactured by American Can Co. of Minn., Minnesota. The fastener 60 may be direct or indirectly bonded to the barrier layer 30, as shown in Figure 1 - Suitable fasteners 60 include, but are not limited to, adhesive fasteners and mechanical fasteners such as VELCRO brand fasteners. Suitable pressure sensitive adhesives from which the fastener 60 can be formed are the Century A-305-IV brand adhesive manufactured by Century Adhesives Corp of Columbus Ohio and the trademark adhesive Instant Lock 34-2323 manufactured by National Starch and Chemical Company of Bridgewater NJ The wrap 22 may comprise a thermoplastic film incorporating a release liner to cover the fastener 60 while sealing the article 20 in the wrapping 22 The release or release lining for the adhesive fasteners are deciphered in the United States patent 4 917 6987 whose patent is incorporated herein by reference. Non-limiting examples of the suitable release liner are BL30MG-A Siliox E1 / 0 and BL30MG-A Silox 4P / 0 manufactured by Akrosil Corp of Menasha Wisconsin The porous cover layer 40 can provide a normalized release rate of at least 025, and more preferably at least 040 while providing a low contact humidity The method for measuring the release coefficient and the standardized release coefficients of the volatile substance of article 20 are deciphered below. The covered porous cover layer may comprise a film formed of a liquid impervious material, a plurality of openings 41 extend through the film In a preferred embodiment, the porous cover layer it may comprise a plastic film formed with openings having a release surface in the form of an outward facing surface 44. The porous cover layer 40 also has an inwardly facing surface 42 In one embodiment the plastic films formed with openings are Preferred because they are generally non-absorbent with respect to the liquid volatile substance and help to prevent the volatile liquid material from passing through the cover layer 40 to make contact with the skin or clothing of the user. The porous cover layer 40 can be attached to the barrier layer 30, either directly or indirectly by a method of suitable numbers In the embodiment shown in Figure 1, the perimeter of the cover layer 40 can be directly secured to the barrier layer 30 by adhesives, heat sealing and / or ultrasonic bonding and the like. Heat sealing method is disclosed in the United States patent ,382,245 issued January 17, 1995 to Thompson et al. The porous cover layer may have a caliber 45 of at least 0,005 inches. The caliber 45 is measured under a compression load of 322 g using a circular loading area that has a diameter of 095 inches (approximately 0 1 psi) The caliber 45 provides the separation of liquid in the substrate 50 and in the outward facing surface 44 of the porous cover layer 40 This caliber 45 helps to restrict the liquid within the substrate 50 that reaches the surface 44 and possibly makes contact with the user's skin or clothing In one embodiment the 45 gauge can be at least about 0 010 inches, and more preferably at least about 0015 inches, and even more preferably at least 0 050 inches, approximately The openings 41 can also be formed to restrict the flow of liquid from the substrate 50 to the outer surface 44 As shown in Figure 3, the openings 41 may be tapered from a relatively large base opening 46 in the outward facing surface 44 to a relatively minor apex opening 48 in the inward facing surface 42. US Pat. No. 3,929,135 issued on December 30, 1975, Thompson is incorporated herein by reference, for the purpose of describing a suitable formed film having tapered openings In an alternate embodiment not shown, openings 41 may be tapered from a relatively large opening in the interior surface 42 to a relatively smaller vertex on the external surface 44 The openings 46 can each have a surface area between about 0.015 mm2 and about 32 mm2. The porous cover layer 40 can have an open area ratio of at least about 10% In one embodiment, the porous cover layer 40 has an open area ratio of at least 20% to about, more preferably at least about 30%, and even more preferably at least about 50%. For example, a suitable cover porous cover layer 40 can have an open area ratio between about 20% and about 50%. This open area ratio is adequate to provide effective release of the volatile material from the substrate. The ratio of the open area is determined by measuring the total area of the surface of the porous cover layer 40 which is located above the substrate 50, as seen in Figure 2, including the area of the openings 46. The areas of The surface of the openings 46 that are located above the substrate are then measured and added together. The surface area is measured at the outward facing surface 44. The open area ratio is the ratio of the sum of the areas of these openings 46 divided by the total area of the surface of the cover layer 40 that is place above the substrate 50 Although the porous cover layer 40 having tapered openings 41 is shown in Figures 1 to 3, it will be understood that other films formed to provide release of the volatile material from the article 20 may also be used, while restricting the volatile material fluid. liquid from substrate 50 to surface 44 Other formed films that can form suitable cover layers 40 are disclosed in the following United States patents, which are incorporated by reference herein, United States Patent 4,324,246 issued to Mullane and others; U.S. Patent 4,342,314 issued to Radel et al .; U.S. Patent 4,463,045 issued to Ahr et al .; U.S. Patent 4,629,643 issued to Curro et al. and U.S. Patent 5,006,394 issued to Baird. A suitable porous layer of cover 40 is marketed as DRI-WEAVE as The Procter & Gamble Company in sanitary napkins In yet another modality, the porous cover layer 40, may comprise a film formed with relatively large apertures (LAFF) Such a LAFF film may be formed to have a generally three-dimensional character from a generally flat sheet of polyethylene having a nominal thickness of about 0 00 5 inches The LAFF film may be formed to have discrete openings 41 arranged in a generally continuous network surface 44. The porous cover layer 40 LAFF may have tapered openings 41 with base openings 46 ranging in size from approximately 0.007 square inches to approximately 0 015 square inches The cover layer 40 of LAFF may have a caliper of at least about 0 050 inches, and may have an open area ratio of at least 20%, more preferably at least 30%, and in some modalities, more than 50% A LAFF 40 cover layer can have an open area ratio of approximately 38%, and a gauge of between about 1 6 and about 1 7 mm A porous cover layer LAFF is available from Tredegar Industpes, under the designation X5870 In yet another embodiment, the open cover porous layer may comprise a sheet of polyvinyl alcohol sheet matepal with Trademark openings MOLDEX, available from Moldex Metric Ine, of Culver City, CA This apertured sheet has discrete apertures 41 arranged in a generally continuous web surface 44 MOLDEX sheet material with openings may have a caliper of at least 2 90 mm, and it may have an open area ratio of about 36%. The substrate 50 may be fibrous and may be in the form of a woven or non-woven patch, a block, a tow a bundle or a bundle of fibers The fibers can be absorbent (for example cellulosic fibers or other natural fibers or non-absorbent with respect to the liquid volatile substance (for non-absorbent)) it is implied that when the substrate 50 is immersed in the liquid volatile substance individual fibers absorb an amount of liquid volatile substance less than their own weight (less than one gram of liquid volatile substance absorbed by the fiber per gram of weight of the fiber) Therefore the liquid volatile substance is stored in the interstitial space between the fibers or along the surfaces of the fiber instead of the fiber inter itself, thereby increasing the release of the liquid volatile substance from the substrate 50. In one embodiment the substrate may comprise fibers formed from such as polyolefin Suitable fibers include but are not limited to polyethylene polypropylene and polyester fibers. The treatment 50 may be attached directly or indirectly to the barrier layer 30 In the embodiment shown in Figure 1, the substrate 50 is directly secured to an inwardly facing surface of the barrier layer 30 by a layer of adhesive 35. Suitable adhesives 35 include the Findley No 2120 adhesive or adhesive Findley H2031 available from Findley Adhesives Ine by Elmgrove Wisconsm and the adhesive available from Century International Adhesive and Coating Corp by Columbus Oh-io In another embodiment the substrate 50 may comprise a plurality of capillary channel fibers 55 The capillary channel fibers 55 are fibers having one or more channels formed therein preferably on their extemal surfaces Figure 4 shows a capillary channel fiber 55 having a generally l-shaped cross section It will be understood that suitable capillary channel fibers 55 can have any number of shapes including but not limited to cross sections in the form of IHCV and U The channels 57 on the outer surfaces of the fiber 55 may have a width W and a depth D The value of W may be between approximately 10 microns and about 100 microns The value of D may be between about 10 microns and about 100 microns. The capillary channel fibers 55 may have a denier of between about and about 45 g / 9,000 m of fiber length. Suitable capillary channel fibers are disclose in the following references which are incorporated herein by reference U.S. Patent No. 5382245 issued January 17, 1995 to Thompson et al. and U.S. Patent 5,200,248 issued April 6, 1993 to Thompson et al. The value of W may be greater than or equal to the value of D. In one embodiment the ratio of W / D may be at least about 15 and more preferably at least about 20 These relatively shallow channels having a ratio of Relatively high W / D are capable of transporting the volatile substance while providing increased release of the substance from the substrate 50 compared to the release that is provided with the fibers 55 having channels 57 with lower W / D ratios In one embodiment the value of D may be between about 15 microns and about 30 microns and the value of W may be between about 40 microns and about 70 microns. The substrate 50 may comprise a region with relatively high density and a region with density relatively low The region with relatively high density provides relatively rapid transport of the volatile fluid through the substrate while the relatively low density region promotes the relatively rapid release of the liquid volatile material from the substrate. The fibers in at least a portion of the substrate 50 can to be operated in a predetermined direction and in one embodiment the fibers in at least a portion of the substrate 50 are arranged in a generally parallel manner to provide the capillary action of volatile liquid in a predetermined direction Referring to Figure 2, the substrate 50 may comprise a region 54 with relatively low density extending between and joining two relatively high density regions 52a and 52b The fibers in the relatively high density regions 52a and 52b may be arranged in a manner generally parallel to provide the capillary action of the liquid volatile substance towards the region with relatively low density The substrate shown in Figure 2 can be formed from a length of generally parallel capillary channel fibers 55 The length of the channel fibers generally parallel capillary can be compressed to warp a portion of the fibers radially outwardly, thus forming the relatively low density region 54. In another embodiment, the substrate 50 may comprise a natural or synthetic sponge material or an open cell foam material Suitable open cell foams such as foams prepared s by polimepzar a high internal phase emulsion, are deciphered in the following United States patent documents, which are incorporated herein by reference US patent application No. of Sene 08/370 695, Absorbent foams made from of high internal phase emulsions useful for capturing and distributing aqueous fluids, filed on January 10, 1995 in the name of Stone et al., United States patent application entitled Absorbent foams made from high internal phase emulsions useful for capturing aqueous fluids, filed on August 30, 1995 in the name of DesMarais, United States Patent 5,147,345, High efficiency absorbent articles for incontinence management, issued September 15, 1992 in the name of Young and others In the described modalities above, the release surface comprises a surface of a porous cover layer 40, wherein the porous cover layer 40 comprises e) a plurality of discrete apertures in a generally continuous network surface 44. Alternatively, the release surface may comprise discrete surfaces forming a generally continuous network opening For example the release surface may be formed by discrete spacers extending from the substrate 50 such as in the form of spikes or other protuberances Referring to Figures 6 and 7 the spacers are designated by numerals 241 Discrete spacers 241 have surface portions 244 which are disposed above the surface of substrate 50 and define the release surface. Spacers 241 are formed to be capable of resisting deformation such as by the tip of a finger which can result from contact of the skin with the substrate 50 The spacing between the separators 241 allows the volatile material to be released from the substrate 50 while the discrete spacers 241 allow a load-resistant release surface with a shaped opening of generally continuous network from which the vapors of the Volatile epal on the substrate 50 can escape The spacers 241 can have any number of shapes or configurations including but not limited to cylindrical spherical mushroom-shaped and combinations thereof Alternately the spacers can comprise elongate elements such as in the form of segments of straight or curvilinear lines As shown in Figure 7 the spacers 241 may extend through the substrate 50 and be integral with or attached to a base sheet 240 The base sheet 240 may be integral with or bonded to the barrier The fibers of the substrate 50 may be entangled around the separators 241 such as by hydroentanglement or may otherwise be forced into the spaces between the separators 241 In yet another embodiment the release surface may be formed integrally with the substrate 50. such as by applying a barrier layer to a contoured surface of the substrate 50 referring to the Figure 9 the substrate 50 can have a contoured surface comprising a plurality of ridges or other protrusions such that a portion of the contoured surface is raised with respect to the other contoured surface portions. In Figure 9 the substrate 50 has a grooved surface comprising peaks. The substrate can be formed to have a contoured surface in any suitable manner, such as by molding a fiber web, or by folding a fiber web to have accordion-like folds. A barrier layer 440 can be applied to the selective portions of the contoured surface such that High surfaces of the surface of the substrate 50 are coated by the barrier layer, while other parts of the surface of the substrate remain uncoated. In Figure 9 the peaks are covered with the barrier layer 440 while the valleys remain uncoated. The barrier layer may comprise a material in the form of curable resin which is its substantially impermeable to liquid material Peaks are formed to be able to resist deformation, such as by the tip of a finger which can result in skin contact with uncoated portions of the substrate 50 Coated peaks and valleys uncoated provide a load resistant release surface that is integral with the substrate 50 and which allows vapors of the volatile material in the substrate 50 to escape. Peak height and stiffness of the substrate 50 are selected to provide low moisture content of the substrate. contact on the barrier layer 440 under a pre-skeleton charge The matepal with which the substrate 50 is impregnated preferably comprises one or more effective components in repelling vermin, including but not limited to insects such as mosquito. Of course, in other embodiments it can It is desirable to impregnate the substrate with a material that provides a desired fragrance regardless of its suitability. an insect repellent Generally, suitable materials with which the substrate can be impregnated include materials having a boiling point of between about 140 ° C to about 290 ° C, and in a mode of between about 230 ° C to about 260 ° C. suitable may have a molecular weight of between 75 and about 300, and in one embodiment a molecular weight of between about 45 and about 257 In one embodiment, the substrate 50 may be impregnated with a liquid material comprising one or more organic compounds These organic compounds they may have between a carbon atom and 20 carbon atoms (organic compounds of C1-C20) and more preferably between 6 carbon atoms and 12 carbon atoms (organic compounds C6-C12) In one embodiment, the substrate is impregnated. with a liquid material comprising one or more organic compounds of C6-C12 These organic compounds can be saturated, unsaturated or aro They can have straight carbon chains, branched carbon chains or cyclic structures Examples of suitable organic compounds include, but are not limited to alkane, alkenes, alcohols, such as citronellol, aldehydes such as citronellal, ketones, esters, amides, phenols, nitnets and lactones A suitable mixture with which the substrate 50 can be impregnated is CITRONELLA CEYLON, designated FLT FDG, FP 138 by International Flavors and Fragrances Ine, of New Jersey Other suitable materials with which the substrate 50 can be impregnated include , but are not limited to, ethyl butyl acetyl aminopropionate, N, N diethyl-M-toluamide (DEET), and dimethyl phthalate. Other suitable examples of a suitable liquid matenal which can be used to impregnate the substrate 50, include mixtures of one or more of the following ingredients: GERALDEHYDE (brand of IFF, genépcamente 5,9-d? met? l-4,8-decad? enal), Citronelil nitpLo, red oil of thyme, eugen, citral (genepc amente 3,7-d? met? l-2,6-octad? en- 1-al), range of methylone, alcohol Beta phenethyl, oil of open cocoon, APO PATCHONE (brand of IFF, generically para-isopropylcyclohexanol), limonene PFG (generically p-Menta-1,8-diene), PEOMOSA ( IFF mark, generically alcohol-o-met? l-betafen? let? lo), and / or VIOLIFF mark (generically 4-C? cloocten? l methyl carbonate) A suitable liquid material that can be used to impregnate the substrate 50 comprises a mixture, in a wt% base of from about 0% to about 5% APO PATCHONE, and about 50% to about 90% Citral, from about 1% to about 10% GERALDEHYDE, of about 5% at about 20% Limonene PFG, from about 5% to about 15% PEOMOSA, and from about 0% to about 5% VIOLIFF, where the percentages are in% weight. A suitable blend comprises about 1% APO PATCHONE, of approximately 75% of Citral, of approximately 05% of GEF iALDEHYDE, of about 15% PURG of ümoneno, of about 7 5% of PEOMOSA and of about 1% of VIOLIFF Another suitable liquid material with which the substrate 50 can be impregnated comprises at least about 15% of GERALDEHYDE and in one mode of between about 15 and about 30% of GERALDEHYDE Yet another suitable material of between about 50 and about 100% of GERLDEHYDE, being with the perfume balance The structures of the present invention can have a substrate 50 impregnated by an initial charge of about 2.0 g or less of the liquid volatile material, and in a mode of about 0 1 or less The weight ratio of the initial charge of the liquid volatile material to the weight of the dry substrate should be about 0 1 In one embodiment the weight ratio of the Initial charge of the liquid volatile material to the weight of the dry substrate 50 is preferably at least 20 approximately, and in an embodiment of at least about 4 0 The structures of the present invention can provide an effective release coefficient of insect repellent material with a relatively small amount of insect repellent material Without being limited by theory, it is believed that the ability of the structures of the present invention to provide an effective release coefficient with a small amount of insect repellent is due, at least in part, to having a relatively high weight ratio of the initial charge of insect repellent material to the weight of the dry substrate In the embodiment shown in Figure 1 the substrate 50 can be impregnated with the liquid volatile material and then sealed in the envelope 22 In an alternative embodiment shown in Figures 5 and 8, the article 20 can comprise a container breakable liquid impervious to liquid containing a predetermined amount of liquid vol 100 and a substrate 50 for receiving the predetermined amount of volatile liquid 100 In the breakable container 90 is capable of being broken by a user to direct the volatile liquid 100 towards the substrate 50 The breakable container keeps the liquid volatile material separated from the substrate 50 , until the article 20 is ready to be used. Therefore, the liquid volatile substance is less likely to evaporate from the article 20 before the time the article in use is placed. The breakable container 90 may comprise a package formed of a layer of liquid. liquid-impermeable matepal For example, the container 90 may comprise a package formed from a polymeca film such as a thermoplastic film. This package may also be formed from a sheet laminate and a polymepal film. The suitable matepales from which the container 90 can be formed include the films and laminates from which it can be formed r the barrier layer 30, as described above In one embodiment, the container 90 can be formed from a film made by Tredegar Industries of Terre Haute Indiana under the designation C 8570 and having a thickness of approximately 0028 mm The breakable container 90 and at least a portion of the substrate 50 can be arranged in a fluid conduit The fluid conduit dipge the amounts previously determined from the volatile liquid 100 from the container 90 to the substrate 50 once the container 90 is broken In Figure 5 the fluid conduit comprises a sleeve 80 having a closed end 82 and an open end 84 In the container 90 is arranged within the sleeve 80 adjacent the closed end 82 At least a portion of the relatively high density region 52a of the substrate 50 extends toward the open end 84 of the sleeve 80 The generally parallel capillary channel fibers 55 in the region 52a extend into the sleeve 80 for carrying out the capillary absorption of the fluid from the broken container 90 towards the region with density The sleeve 80 can be attached to the substrate 50 to form a seal against the fluid. For example, the open end 84 of the sleeve 80 can be adhesively bonded to the substrate 80 to prevent the previously determined quantity of liquid 100 from flowing between the substrate 50. and the sleeve 80. The sleeve can be formed of a liquid impermeable film such as a polymeca film which is substantially non-absorbent with respect to the liquid volatile substance. Suitable materials from which the sleeve can be formed include those films and laminates. from which the barrier layer 30 can be formed. Other suitable films from which the sleeve 80 can be formed is the SARAN brand wrap manufactured by Dow Brands Ine of Indianapolis Indiana. In another embodiment the substrate 50 can comprise a non-woven web of paper fiber including paper webs made by ai drying techniques re continuous as well as by conventional paper-making techniques.

Suitable starting materials from which the substrate 50 can be formed are disclosed in the following United States patents which are incorporated herein by reference United States patent 4,528,239 issued July 9, 1985 to Trokhan United States patent 5,277,761 issued on January 11, 1994 to Phany others, and U.S. Patent 5,245,025 issued September 4, 1993 to Trokhan et al. In one embodiment the substrate 50 may have a weight of between about 0-20-040 grams, and may comprise 2 or more sections of paper towels of two sheets cut from paper towels of the BOUNTY trademark manufactured by The Procter & Gamble Company Figure 10 illustrates an example of article 20 according to the present invention article 20 includes a substrate 50 measuring approximately 25 inches by inches and having a dry weight of approximately 030-035 grams The substrate comprises two layers one above the other and each layer comprising a sectional cut of 25 inches by 2.5 inches from a two-sided paper towel of the BOUNTY trademark The substrate 50 is impregnated with about 1.5 grams of a liquid volatile matepal comprising one or more of the ingredients listed above. The substrate 50 is disposed between the porous cover layer 40 LAFF decop arpba and a barrier layer The cover layer 40 measures from approximately 2 9 inches by approximately 29 inches, and the barrier layer 30 measures from approximately 3 inches by approximately 325 inches. The barrier layer comprises a generally transparent laminate film. The transparent film is desirable to reduce the visibility of article 20, as used. The laminate film comprising layers of polyethylene terephthalate, ethyl vinyl alcohol (PET), and low density polyethylene (LDPE). Film is available from Curwood Co of New London, Wisconsin LDPE layer barrier layer 30 can be attached to the porous cover layer 40 by an adhesive or by heat sealing A removable top film 30 has its perimeter vibrably sealed with heat to the perimeter of the barrier layer 30 extending beyond the edges of the porous cover layer 40 The separable top film 30 'comprises a PET laminate, a Nylon 6 aluminum sheet, and Surlyn El Surlyn faces towards the upper film 30 'facing the LDPE surface of the barrier layer 30 and can be melted to provide a seal with separable heat between the superheated film. and the barrier layer 30 The heat seal joining the upper film 30 'the barrier layer 30 is approximately 3/16 inches wide The heat seal provides the removable attachment of the separable upper film 30 to the barrier layer Together, the upper film 30 ', and the barrier film 30 provide a sealed behavior that prevents evaporation of the liquid volatile material from the substrate 50. Fig. 10 has a fastener 60 attached to the outward facing surface of the barrier layer 30 The fastener 60 comprises a layer of pressure sensitive adhesive bonded to the barrier layer 30 A removable paper cover 61 having a surface covered with silicone that faces inwards, is placed on the surface that gives out of the layer of the pressure sensitive adhesive before fixing the article to the target surface The total weight of the article, including liquid volatile material but not counting the weight of the peelable paper cover 61 and the separable top film 30 ', is approximately 33 grams The width and thickness of the article (thickness measured using a loading area of 095 inches and a load of 32 2 grams ) are approximately 325 inches and approximately 27 mm respectively. The articles of the present invention may have a stiffness not greater than about 005 pounds / in. and preferably not greater than about 0 1 pounds / inch when measured using a 3-point bending test The 3-point bending test is conducted using a suitable tension tester such as a model 1122 tester of the INSTRON trademark fitted with a compression load cell of 2 kgms to measure the rigidity of article 20 article 20 is supported on two hopzontal layers separated by 10 inches apart so that the article bypasses the space of 0 1 inches between the two horizontal plates (the space of one inch measured parallel to the length of the article) A 1/8 inch thick plate is held over the crosshead of the tester in such a way as the crosshead moves down the edge of the 1/8 thick plate moves down and makes contact with the article half the way along the length of the article pushing the article into the space between the two horizontal layers The crosshead moves at a speed of 1 inch per minute The peak load measured as the spider travels down is recorded. The peak load is divided by the width of the article to obtain the stiffness of the article in pounds per inch. The pliability of the items such as those shown in Figure 10 was measured using the above procedure The registered peak loads range from about 0 09 pounds to about 0 019 pounds which for the 325 inch width of the articles corresponds to a 3 point bending stiffness of between about 003 pounds / inch and 006 pounds / inch MEASUREMENT OF CONTACT HUMIDITY The contact humidity of the release surface of article 20 is measured by pressing the article and a piece of filter paper with a confining pressure of 10 psi for a period of 10 seconds, and measuring the amount of the liquid material that is transferred from the article to the filter paper The filter paper is paper filter of class No 989 made by Ahlstrom Filtration Co, from Mt Holly Sppngs The filter paper of class No 989 has a composition of cellulose fiber and an unfinished white surface The filter paper has a basis weight of 137 g / m2 a thickness of 070 mm, a permeability Frazier of 39 / cfm / p? e2, a capillary lift of 87 mm / min and a retention of 55 micrometers The contact humidity is measured at a temperature of about 70 ° plus or minus 2o, and a relative humidity of about 55% If the item comes with an envelope (the substrate is pre-impregnated) the contact angle is measured as follows A piece of filter paper is cut so that it has a length and width dimensions as large as those of the substrate 50 A dry filter paper is weighed It is removed the wrapping that seals the article 20 and the article is placed immediately on a flat horizontal surface with the release surface facing upwards. Then the filter paper is placed on the release surface of the article that is placed per 50 of the substrate 50 One weight is gently lowered onto the filter paper to apply a uniform pressure load of 100 psi on the substrate (the weight is selected such that the weight divided by the product of the length and width of the substrate as seen in Figure 2 equal to 1 0 psi) The pressure load is maintained for 10 seconds, after which the weight is removed and the filter paper is weighed again. The difference between the first and the second weight of the Filter paper is the contact angle for the sample The standard contact humidity of the sample is the humidity of contact divided by the weight of the liquid material that originally impregnates the substrate If the substrate is not impregnated (such that liquid volatile matepal must be applied to the substrate by the user before using the article) then the above procedure is used with the following modification The liquid volatile material is applied to the substrate. The article is then maintained by the flat horizontal surface with the release surface facing up for 10 minutes to allow the liquid material to be dispersed throughout the length of the substrate. After 10 minutes the Filter paper on the release surface and load pressure is applied MEASUREMENT OF THE RELEASE COEFFICIENT The release coefficient of an article that has liquid volatile matepal is measured using the following procedure. The release coefficient is measured in a chamber with fume hood of the commercial brand KEM PONENT which measures approximately 4 feet x 3 feet x 4 feet and manufactured by Kewaunee Scientific Corp De Adrián Michigan The bed is used with a vent opening the fan turned on and the glass guard raised to the open position The chamber provides an air velocity of approximately 150 feet / mm as measured using a vaneometer manufactured by Dwyer Instrument Co of Michigan City Indiana The chamber is maintained at a temperature of 70 ° F plus or minus 2 ° The pressure in the chamber is maintained at approximately one atmosphere and the relative humidity in the chamber is maintained at approximately 55%. A ring holder is placed inside the chamber. chamber for holding articles for which the release coefficient is to be measured For articles that have a substrate pre-impregnated with a liquid volatile material and sealed to prevent evaporation of the volatile liquid material, the Release coefficient using the following measurements The seal that avoids evaporation is removed and the article is immediately weighed on a balance located in the chamber to obtain a starting weight of the article or WB in grams The article is then held on the ring support inside the camera After an hour the article is weighed again on the scale This weight is the weight of the article in one hour W1 The weight of the article is re-measured at intervals of one hour to obtain the weight of the article in two hours W2 the weight of the article between three hours W3 and the weight of the article W4 The article is held on the ring support inside the chamber between each weight measurement After 4 hours the article is held on the ring support and pepodically it becomes in spite of the fact that substantially all the volatile material of the article has escaped such that there is no significant change in the weight of the article in post-weighing One-hour intervals The weight of the article at this point is the weight of the dry article WD The macroscopic surface band that gives the substrate 50 that was wetted by the liquid volatile matepal is designated SA and is measured in square inches per surface area "macroscopic" is meant to mean the surface area of the substrate calculated from the pepmet-fold dimensions (eg length and width) of the substrate as it differs from the microsurface area of the individual fibers or filaments that form the substrate. The surface area SA is measured when the substrate is substantially dry Those portions of the surface area of the substrate that are sealed (such as by a sleeve 80 (so that they can not release the volatile liquid material are not counted in the SA area measurement If the article is measured has a porous cover layer 40 the surface area SA is the portion of the surface area of the substrate that lies above e the porous layer of cover 40 and which is capable of releasing the material volatile liquid ie unsealed, such as by a sleeve 80) by way of example the surface area SA of the substrate 50 shown in Figures 1 and 2, indicates the combined surface areas of the regions 52A, 52B and 54 underlying the porous cover 40, as seen in Figure 2. In the embodiment shown in Figure 5, the surface area SA would not include the portion of the region. 52A covered by the sleeve 80 For articles having a substrate that is not pre-impregnated with a volatile liquid material, the release coefficient is determined from the following measurements. The macroscopic surface area SA of the dried substrate is measured. dry article, WD is measured with a balance The article then impregnated with liquid volatile material and immediately weighed with a balance to obtain the weight of the starting article WB The article is then held on a ring support inside the chamber After a Once the article is again weighed on the scale, this weight is the weight of the article in one hour, W1 The article is reweighed at intervals of 1 hour to obtain the weight of the article in two hours, W2 the weight of the article in three hours W3 and the weight of the article in four hours W4 The article is held on the ring support inside the chamber between each weight measurement The coefficient of release of articles which have pre-impregnated and non-pre-impregnated substrates can be calculated as follows The weight of the liquid volatile material initially in the article is WL and is equal to WB-WD in grams The release coefficient in one hour of the article is weight (WB -W1), in grams of the liquid volatile material released in the hour per square inch of the surface area SA of the substrate per gram of the liquid volatile matepal initially in the article The release coefficient in one hour R1 is calculated as (WB-W1 grams) / IWL grams) x (SA inch2) -hour) The coefficient of release in two hours, R2, can be calculated as follows (W1-W2 grams) / (WL grams) x (SA in2) hour) The release coefficient in three hours R3 can be calculated as follows (W2-W3 grams) / (WL grams) x (SA in2) hour) The coefficient of release in four hours extended R4 can be calculated as follows (W3-W4 grams) / (WL grams) x (SA in 2 hours) In one embodiment the present invention provides a release coefficient in four hours extended R4 which is at least 50% approximately and most preferably at least about 80% release coefficient in one hour R1 in order to determine a normalized release coefficient for the article The following measurements are made A petp dish having a depth of approximately 047 inches and an internal diameter of 1 7 inches (to provide a surface area of petp SP of 2 27 square inches) is weighted to provide a dish weight clean vacuum WP It is added from approximately 1-5 to approximately grams of the same liquid with which the substrate 50 is impregnated to the plate in such a way that the lower part of the plate is covered. The petn plate and the liquid are immediately weighed to provide WBP with the starting weight of the plate and the liquid. The weight of initial liquid is WLP = WBP-WP The plate is placed in the chamber with smoke collection hood under the same conditions described above with respect to the measurement of the release coefficients of article 20 After one hour the plate is weighed in the balance This weight is the weight in one hour WP1 The coefficient of release of petp RP is RP = (WBP-WP1) grams / t (WLP grams x (SP) in2 hours) The coefficient of release in a normalized hour R1N and the ratio of the release coefficient R1 divided by the coefficient of release of petp in one hour RP or R1n = R1 / RP Similarly, the normalized release coefficients in two hours, in three or four, are R2 / RP, R3 / RP and R4 / RP Table 1 below lists the results of the humidity test of contact for the different disposable patch constructions, the different patch types designated aF The aE patches are articles according to the present invention Patch type F is a commercially available REPELLO-PATCH brand patch described below Table 2 below lists the results of the release coefficient test and the results of the standardized release coefficient test for the AE patch constructions Table 1 Contact Humidity (CW) a Substrate (50) Bounty 2-ply towel, 2 5"x 2.5" Liquid 1 5 g of GERALDEHYDE Cubase coat (40) LAFF CW (n = 5) 17 mg, 0 5 mg, 0 8 mg, 1 0 mg, 1 9 mg / media 1 3 mg CW standardized 0 87 mg / gram B Substrate (50) Bounty 2-layer towel, 1 5"x 4" Liquid 2 0 g Citronela Ceylon Cubite coat (40) LAFF with 38% open area CW (n = 5) 29 mg 17 mg 20 mg, 15 mg, 23 m / mean 21 mg CW normalized 10 5 mg / gram C Substrate (50). Bounty 2-layer towel, 1 5"x 4" Liquid 20 g Citronella Ceylon Cuborta layer (40): Always Ultra top sheet (DRI-WEAVE) CW (n = 3) 25 mg, 20 mg, 27 mg / media 24 mg CW standardized 12.0 mg / gram D Substrate (50) - 2-layer, 1.5"x 4" Bounty Towel Liquid: 2.0 g Citronella Ceylon Cubite Coat (40): MOLDEX CW Sheet (n = 3) 1 O mg, 05 mg, 08 mg , 1 1 mg, 1.3 mg / media 09 mg CW standardized 0 5 mg / gram E Substrate (50) - Bounty 2-layer towel, 1 5"x 4" Liquid: 2 g Citronella Cylon Ceylon coat (40) 'Surgical tape No 1525 of the trademark 3M Blenderm CW (n = 5 ) 29 mg, 17 mg, 20 mg, 15 mg, 23 mg / medium 21 mg standardized CW 10 5 mg / gram F. Substrate (50) REPELLO-PARCH BRAND Liquid. Average of approximately 0.73 g of Citronella Cover Layer (40) None CW (n = 5) 051 gm, 035 gm, 040 gm, 039 gm, 0.36 gm / average 0.40 gm CW normalized 0.55 g / gm or (550 mg / gm) Cuador 2 Liberation Coefficients RP (Geraldehyde, 1 5 g in dish, n = 5) = 2 64 mg / gm-in2-houra Substrate (50) 2-layer Bounty Towel, 25"x 2.5" Liquid 1 5 g GERALDEHYDE Cubite Coat (40) LAFF Release Coefficients (mg / gm-in2-hour) (n = 5) R1 1 07 R2 1 39 R3 0 83 R4 0 83 R4 / R1 077 Normalized Release Coefficients (without dimensions) based on RP = 264 R1N 040 R2N 0 53 R3N 0 31 R4N 0 31 RP (Ceylon citronella, 20 g in dish, n = 5) = 284 mg / gm-in2-hour (n = 5) B Substrate (50) Bounty 2-layer towel, 1 5"x 4" Liquid 2 0 g Citronela Ceylon Coating layer (40) LAFF with 38% open area Release Coefficients (mg / gm-in2-hour) (n = 2) R1 19 0 R2 132 R3 94 R4 6 5 R4 / R1 = 0 34 Normalized Release Coefficients (without dimensions) based on RP = 284 R1N 067 R2N 046 R3N 033 R4N 023 C Substrate (50) Bounty 2-layer towel, 1 5"x 4" Liquid 20 g Citronella Ceylon Cuborta (40) Always Ultra top sheet (DRI-WEAVE) Release Coefficients (mg / gm-in2-hour) (n = 2) R1 162 R2 106 R3 66 R4 57 R4 / R1 = 0 35 Normalized Release Coefficients (without dimensions) based on RP = R1N 0 57 R2N 0 37 R3N 0 23 R4N 0 20 D Substrate (50) Bounty 2-layer towel, 1 5"x 4" Liquid 2 0 g Citronela Ceylon Coating Cap (40) MOLDEX Sheet Coefficients of Release (mg / gm-in-hour) (n = 2 ) R1 11 1 R2 95 R3 64 R4 1 9 R4 / R1 = 0 17 Normalized Release Coefficients (without dimensions) based on RP = 284 R1N 0 39 R2N 0 33 R3N 022 R4N 0 07 E Substrate (50) Bounty 2-layer towel 1 5"x 4" Liquid 2 0 g Citronela Ceylon Coating layer (40) Surgical tape No 1525 of the trademark 3M Blenderm Release Coefficients (mg / gm-in2) -h) (n = 2) R1 6 2 R2 6 1 R3 54 R4 1 6 R4 / R1 = 0 26 Normalized Release Coefficients (without dimensions) based on RP = 284 R1N 022 R2N 021 R3N 0 19 R4N 006 The release coefficients in one and two hours were also measured for a ppmera sample of a bug repellant patch commercially available as REPELLO-PATCH by P J Maxwell The tested REPELLO-PATCH sample had a uncoated dry substrate having an SA surface area of approximately 3 5 in2 and a separately packed liquid material that was added to the substrate. The separately packed liquid material was labeled as being 99% citronella. Approximately 075 grams of the separately packed liquid material was added. to the substrate The coefficient of release was determined in one hour to be approximately 00098 gram / in2-gram-hour and the release coefficient was determined in two hours to be approximately 0,0074 grams / in2-gram-hour The release coefficients were also measured in a two three and four hours for a second sample of a REPELLO-PATCH trademark patch with the following results in grams / in2-gram-hour 00048 00040 0 0036, and 0 OOS-l In the described embodiments the substrate 50 is impregnated with the effective substance to repel insects In other embodiments the Substrate 50 can be impregnated with materials that are effective in providing a desired fragrance such as perfume materials or combinations of these materials Although particular embodiments of the present invention have been illustrated and described, it is obvious to those skilled in the art that they can be made vain changes and modifications without departing from the spirit and scope of the invention It is intended to protect, in the appended claims t all these modifications and intended uses

Claims (1)

1. CLAIMS A disposable, portable article for providing release of a liquid volatile substance from an article release surface, the article comprising a substrate impregnated with liquid volatile material wherein the release surface of the article has a contact humidity of less than 100. mg gram, more preferably less than 50 mg and even more preferably less than 25 mg 2 The disposable, portable article according to claim 1, wherein the release surface has a normalized contact humidity of less than 100 mg / gram, more preferably less than 25 mg / gram 3 The disposable, portable article according to claims 1 and 2, wherein the article has a normalized release coefficient of at least 0 25, more preferably at least 040, and even more preferably at least 0 50 Disposable portable article, according to claims 1, 2 and 3, wherein the article has a substrate impregnated with 2 0 grams or less of the liquid volatile material 5 The portable article, disposable, in accordance with the claims 1 2, 3 and 4, wherein the ratio of the weight of the liquid volatile material to the weight of the substrate is at least 2 0 6 The portable article, disposable, in accordance with the claims 1, 2, 3, 4, and 5, wherein the article has a maximum caliper not greater than 3 0 mm 7 The disposable portable article, according to claims 1, 2, 3, 4, 5 and 6, in wherein the volatile liquid material comprises an insect repellent. The disposable, portable article according to claims 1, 2, 3, 4, 5, 6 and 7, comprising a porous cover layer to provide the release of the volatile substance of article 9 The disposable portable article according to claim 8, wherein the porous cover layer has an open area ratio of at least 20%, and more preferably at least 30%. The portable, disposable article according to claims 8 and 9, wherein the porous cover layer has a caliper of at least 0 015 inches, and more preferably at least 0 050 inches