Abstract:
Described is a formulation for delivering fish attractants that sustains the release time as well as provides high coating power. The composition is made with a stable water-in-oil emulsion of petrolatum jelly, a water soluble delivery agent, a thickening agent, and a water soluble fish attractant. These formulations stick well to the exterior surface of artificial lures while allowing the active attractant ingredient to be released slowly into the water. The formulations are also in the form of a soft gel that is easily applied to the surface of a lure by dunking the lure in a wide-mouthed container or squeezing the gel from a conventional container.

Description:
This application claims the benefit of U.S. Provisional Application 60/015,745 filed Apr. 23, 1996. 
     FIELD OF THE INVENTION 
     The present invention relates to a formulation for delivering fish attractants that sustains the release time as well as provides high coating power. 
     BACKGROUND OF THE INVENTION 
     The art of fishing involves a mix of angling techniques and equipment to persuade fish to bite on the bait, whether artificial or natural. A wide variety of devices, baits, and auxiliary agents are used to stimulate the various senses of fish (visual, electrical, pressure, etc.), replicate natural feeding patterns, and stimulate aggressive attack responses. The literature directed to such techniques, devices, and agents are legion. 
     One area of particular interest is that of chemical fish attractants and the formulations for delivering them to the target fish. Fish attractants must be water soluble to be effective. Unfortunately, water soluble attractants are quickly removed from a lure when applied as a surface coating. Various formulations have been disclosed for releasing the water soluble fish attractants. See, Prochnow U.S. Pat. No. 4,826,691 (powdered membrane film and powdered attractants applied to surface of wet lure to form gelatinous film on surface) and Prochnow U.S. Pat. No. 5,089,277 (attractant dispersed in moldable dough of cellulose ether and polyalkylene glycol), the disclosures of which are herein incorporated by reference. 
     Despite the technology used in such prior products, there exists a continuing need to provide attractant formulations that are easy for an angler to use with a variety of lures under angling conditions that range from stable fishing docks to wind-tossed seas. 
     SUMMARY OF THE INVENTION 
     It is an objective of the present invention to provide a formulation for water soluble fish attractants that sticks well to bait surfaces and which controls the rate of release. 
     It is another object of the invention to provide an attractant formulation for use on fishing lures that is easy to apply, withstands repeated exposures to casting forces and resists removal when a lure coated therewith is fished. 
     In accordance with these and other objectives that will become apparent from the description herein, attractant formulations according to the invention comprise: (a) a stable water-in-oil emulsion made of petrolatum jelly, a water soluble delivery agent, a thickening agent, and (b) a water soluble fish attractant. 
     Formulations according to the invention stick well to the exterior surface of artificial lures while allowing the active attractant ingredient to be released slowly into the water. The formulations are also in the form of a soft gel that is easily applied to the surface of a lure by dunking the lure in a wide-mouthed container or squeezing the gel from a conventional container. 
     DETAILED DESCRIPTION 
     Fish attractant formulations according to the invention are made with (a) a stable water-in-oil emulsion of petrolatum mineral jelly or wax, a water soluble delivery agent, a thickening agent, and (b) a water soluble fish attractant. The petrolatum provides an oil-based carrier that adheres well to the external surfaces of artificial lures. The remaining ingredients form a chemically compatible, stable emulsion with good shelf stability that releases the active attractant slowly when immersed in water. 
     Unless otherwise stated, all percentages are by weight. 
     Water soluble delivery agents useful in the invention are water soluble, able to dissolve the attractant, immiscible in the petrolatum, nontoxic, and environmentally acceptable. Useful agents include materials high in hydroxyl (--OH) functionality such as glycols (e.g., ethylene and propylene) and glycerin. Particularly preferred delivery agents include propylene glycol and glycerin. 
     Thickening agents useful in the invention are those materials that will thicken the petrolatum sufficiently to stabilize the emulsion without prohibiting release of the attractant. Suitable thickening agents are solid, semi-solid, and liquid at room temperature. Preferred thickening agents include ethylene-acrylic acid copolymers, polyethylene waxes, silica (e.g., Cab-O-Sil™), naturally occurring silicates, and naturally occurring silicate clays. The most preferred agent is fumed silica. 
     The attractant to be incorporated into the present formulation may be any water soluble material or combination of materials which attract or stimulate aquatic life, such as fish and crustaceans, to feed. A wide variety of attractants, including those cited in the background prior art discussed in U.S. Pat. Nos. 4,245,420; 4,826,691; and 5,089,277, (the disclosures of which are herein incorporated by reference) have been found to be suitable. Examples include powdered bone meal, powdered food solids, powdered anise, rhodinyl acetate, dehydrated fish meal, dried slaughterhouse waste products, powdered fish, egg, dried milk products, sodium chloride, molasses, fish powders and synthetic spices having a smell similar to that of fish meal, fish oil, stale fish, shell fish, krill powder, pulverized dried sardine, spray dried inactivated and/or autolyzed yeast, powdered squid, borax, wood flour, bentonite, pulp fibers, and cellulosic materials, dicarboxylic amino acids and other amino acids, such as glutamic and aspartic acids, betaine, glycine, alanine, taurine, tryptamine, and tyramine. 
     Academic study of fish behavior relating to chemoreception describes a wide variety of attractant materials suitable for use in the present formulation. Very useful attractant are disclosed in the following publications, the disclosures of which are herein incorporated by reference: 
     a. Hara, Toshiaki J., &#34;Chemoreception,&#34; Fish Physiology, Vol. 5, 1971, pp. 79-120, Academic Press Inc. 
     b. Hara, Toshiaki J., &#34;Olfaction in Fish,&#34; Progress in Neurobiology, Vol. 5, Part 4, 1975, pp.271-335, Pergamon Press. 
     c. Hara, Toshiaki J. (Ed.), &#34;Chemoreception in Fishes,&#34; Developments in Aquaculture and Fisheries Science, 8, 1982, Elsevier Scientific Publishing Co. 
     d. Pitcher, Tony J. (Ed.), &#34;The Role of Olfaction in Fish Behavior,&#34; The Behavior of Teleost Fishes, 1986, pp. 152-176, The Johns Hopkins University Press. 
     The percentage of attractant in the present formulation is determined primarily by the nature of the specific attractant material. Certain attractants, which have an extremely concentrated attractive effect on aquatic life, may be used in the present formulation in amounts as low as between about 0.1-10% of the total formulation. When bulky or general attractants, such as powdered fish meal, are used in the present formulation, they are generally present in an amount of at least about 5% of the total formulation. Broadly, formulation of the present invention containing amounts of attractant in the range of between about 0.1-80% of the total formulation have been found to be effective in luring aquatic life. 
     Preferred formulations for the present fish attractants comprise about 50-80% petrolatum, 10-30% water soluble delivery agent, 1-10% thickening agent, and 0.01-20% attractant, and 0-20% auxiliary agents. Particularly preferred formulations include 60-65% petrolatum jelly, 20% water soluble dispensing agent, 3-5% thickening agent, and 10-20% (especially 10-12%) water soluble attractants and other ingredients. 
     The particular ingredients of the attractant formulation can be blended in any manner that produces a stable water-in-oil emulsion. If the thickening agent is a solid at room temperature and meltable, that component may be heated until a liquid and mixed with the other components at high speed until a creamy, stable emulsion is formed. Generally, the components are mixed at room temperature by hand or with a mechanical mixer until the mixture changes from a dry, stiff mix into a smooth, creamy paste that can be readily applied to the exterior of a bait or artificial lure. 
     Stability of the final formulation can be measured by a number of different tests. One technique that has proven to be a reliable indicator of stability for commercial formulations has been the performance of a formulation that has withstood heating to a temperature of about 70° C., extended storage in a freezer at temperatures below 0° C., and exposure to ultraviolet light. 
     The consistency of the formulation is measured by the conventional cone penetration method (ASTM D937). In that method, a weighted cone is allowed to penetrate into the formulation after a given period of time. Softer formulations will penetrate to a greater depth. Pure petrolatum will penetrate to a depth of about 150-190 dmm (tenths of a millimeter). Formulations according to the invention penetrate to a depth within the range from about 150-500 dmm, preferably within the range from about 200-300 dmm, and most preferably to a depth within the range from about 200-250 dmm. 
     In use, the lure is coated with the formulation by any suitable method depending on the viscosity of the final formulation and the available packaging/dispensing containers available. Suitable packaging/delivery containers include squeeze bottles with container walls sufficiently flexible to be squeezed and force the formulation through a resealable nozzle or wide mouth jars of plastic or glass of sufficient dimensions that allow a lure to be directly dipped into the formulation while attached to the end of a fishing line. 
    
    
     EXAMPLES 
     A formulation according to the invention having the agents and concentrations identified in Table 1 was prepared. The formulation was stable through a wide range of conditions. 
     
                       TABLE 1______________________________________         WEIGHT %______________________________________Petrolatum      60.5Delivery Agent  20Thickening Agent           4Attractant      14.5Coloring agents and           1preservatives______________________________________ 
    
     The formulation of Table 1 was applied to the surface of several types of artificial fishing lures and used as each would be in conventional fishing. The formulation was mixed in a wide mouth jar that allowed each of the lures to be dipped into the jar and thereby coated with the fish attractant formulation. 
     
                       TABLE 2______________________________________LURE       SURFACE OF LURE                    RETENTION______________________________________Suspending jerk bait      dimpled sides, smooth                    after 12 casts, film re-      top and bottom                    mained (2 trials)Wooden, med. deep      Slight grooves,                    After 20 casts, a thincrank bait generally smooth                    film still remainedPlastic worm      Small ribs    after 4, 5, and 7 casts, thin                    coating remainedSm. minnow Slightly grooved sides                    at least 1/3 remainedcrank bait               after 12 castsSm. shallow      Smooth        thin film and globularcrank bait               deposits remained after 2                    mins. trolling and 20 casts______________________________________ 
    
     The formulation showed exceptional adhesion under a variety of fishing conditions over differing lure surfaces. 
     The preceding example is presented solely to facilitate an understanding of the present invention. The details of the examples are not intended to serve as a limitation on the scope of the appended claims.