Liquid antimicrobial, skin moisturizing formulation

A liquid antimicrobial, skin moisturizing formulation including: 1) an aqueous alcoholic base; 2) a humectant; 3) a delivery material adapted to release an emollient when the formulation is applied to the skin; and 4) an emollient imiscible in the aqueous alcoholic base and contained by the delivery material. The delivery material encapsulates or entraps the emollient for subsequent release. Desirably, the humectant is glycerin and the emollient is an alkyl-substituted polysiloxane polymer.

FIELD OF THE INVENTION
 The present invention relates to liquid formulations for personal cleaning
 that have antimicrobial activity.
 BACKGROUND
 Alcohol is used to disinfect hands and body surfaces. In various forms, it
 is increasingly being used as hand antiseptics, both to supplement soap
 usage, as well as for situations where soap and water are not readily
 available. Ethanol and propanols exhibit broad spectrum antimicrobial
 activity and are non-allergenic, fast-acting, miscible in water, and
 relatively non-toxic.
 These alcohols are effective against a wide variety of bacteria (Gram
 positive and Gram negative), yeast, molds, and viruses. Unfortunately,
 they are ineffective against bacterial spores, have no residual action,
 and are drying to the skin. Viscosity increasing agents (e.g., thickeners)
 are often added to alcohols to prevent runoff and to increase residence
 time on the skin. While longer residence time tends to enhance
 antimicrobial action it also tends to magnify certain undesirable side
 effects. Frequent use of alcohol gels may cause skin irritation and reduce
 the skin moisture level. This can be a problem for health care
 professionals, child care providers, food service workers and others who
 use alcohol gels to disinfect or sanitize their hands. Skin irritation
 from frequent use of alcohol gels may also be a problem for many persons
 suffering from temporary or chronic digestive tract disorders.
 Some alcohol gel formulations contain skin moisturizers or conditioners.
 Unfortunately sufficiently high levels of some of these moisturizers
 and/or conditioners may cause instability in the alcohol gel over time and
 could cause the gel to lose viscosity. In addition, at sufficiently high
 levels these moisturizers and/or conditioners may provide unpleasant
 tactile sensations after application but before being absorbed by the
 skin. For example, high levels of moisturizers such as glycerin tend to
 provide an unpleasant tacky sensation until the glycerin is absorbed by
 the skin.
 Thus, there is still a need for a liquid antimicrobial formulation that may
 be applied to the skin without causing drying and irritation. There is
 also a need for a liquid antimicrobial formulation that moisturizes skin.
 A need exists for a liquid antimicrobial formulation that includes an
 emollient or other component that counteracts or offsets any unpleasant
 tactile properties of the formulation.
 Meeting these needs are important since it is desirable to disinfect and/or
 sanitize skin while maintaining good skin health with formulations that
 employ generally inexpensive, and readily available materials.
 SUMMARY OF THE INVENTION
 The problems described above are addressed by the present invention which
 provides a liquid antimicrobial, skin moisturizing formulation including:
 1) an aqueous alcoholic base; 2) a humectant; 3) a delivery material
 adapted to release an emollient when the formulation is applied to the
 skin; and 4) an emollient imiscible in the aqueous alcoholic base and
 contained by the delivery material. Generally speaking, the delivery
 material encapsulates or entraps the emollient and then releases the
 emollient when the formulation is applied to the skin.
 The emollient should be imiscible in the humectant as well as the aqueous
 alcoholic base. It is contemplated that the emollient may have some
 relatively low level of miscibility with the aqueous alcoholic base and/or
 humectant, depending on the type of emollients used.
 The delivery material may be a particulate material and may be a finely
 divided material such as a powder-like material that may be readily
 dispersed in the aqueous alcoholic base. A feature of the invention is
 that the delivery material holds or contains the emollient and then
 releases the emollient when the formulation is applied to the skin. In an
 embodiment of the invention, the delivery material may encapsulate the
 emollient. For example, the delivery material may be gel capsules, small
 plastic beads or spheres and/or similar bubble like structures composed of
 a single or multiple layers that hold or surround the emollient.
 In an embodiment of the invention, the delivery material should entrap the
 emollient. For example, the delivery material may be adsorbent or high
 surface area particulate materials such as certain starches, talcs, clays,
 metals, polymeric entrapment materials and the like.
 Desirably, the particulate delivery material is a polymeric entrapment
 material formed from a variety of polymers such as, for example,
 polyolefins, nylons, polyacrylics and the like. Exemplary polymeric
 entrapment materials include one or more materials having the CTFA
 designation acrylates copolymers. Exemplary acrylates copolymers may be
 characterized as cross-linked methacrylates appearing as a white,
 free-flowing powder. Suitable acrylates copolymers may be obtained from
 Advanced Polymer Systems of Redwood City, Calif., under the trademarks
 Microspong.RTM. and Polytrap.RTM..
 Generally speaking, the formulation will contain from about 0.1 to about 5
 percent, by weight, of the delivery material containing the emollient.
 Relatively small amounts of delivery material may be used if it is capable
 of containing and delivering relatively large amounts of emollient. On the
 other hand, relatively large amounts of delivery material may be needed if
 it is capable of containing and delivering relatively small amounts of
 emollient.
 The emollient may be one or more liquid hydrocarbons (e.g., petrolatum),
 mineral oil and the like, vegetable and animal fats (e.g., lanolin,
 phospholipids and their derivatives) and/or a silicone materials such as
 one or more alkyl substituted polysiloxane polymers. More desirably, the
 emollient is dimethicone or dimethicone and one or more other alkyl
 substituted polysiloxane polymers.
 In some embodiments of the present invention, it is contemplated that
 liquid hydrocarbon emollients and/or alkyl substituted polysiloxane
 polymers may be blended or combined with one or more fatty acid ester
 emollients derived from fatty acids or fatty alcohols.
 According to an aspect of the present invention, the emollient reduces the
 undesirable tactile attributes of the formulation that may be caused by
 the humectant component. For example, a dimethicone emollient will reduce
 the level of tacky or sticky sensation that may be caused by the glycerin
 humectant in the formulation. It is contemplated that the delivery
 material may also help reduce undesirable tactile attributes of the
 formulation that may be caused by the humectant component.
 While the loading of the emollient in the particulate delivery material
 will vary depending on the maximum liquid load for the particulate
 delivery material, particulate delivery materials may contain from about
 10 to about 80 weight percent, based on the weight of the particulate
 delivery material, of the emollient. This level may be at the lower end of
 the range for starches and talcs and may be at the upper end of the range
 for acrylates copolymers. For example, when certain agglomerated acrylates
 copolymers are used, they may be loaded with from about 30 to about 75
 weight percent, based on the weight of the particulate delivery material,
 of an emollient. As another example, the particulate delivery material may
 contain about 50 to about 70 weight percent, based on the weight of the
 particulate delivery material, of an emollient.
 The humectant may be a water soluble polyhydric alcohol having from 2 to 3
 hydroxyl groups and blends thereof. Desirably, the humectant is glycerin.
 The amount of humectant in the formulation may vary depending on the level
 of moisturizing desired. Desirably, the level of humectant may range from
 about 1 to about 15 percent, by weight. For example, the formulation may
 contain from about 1 to about 5 percent, by weight, of the humectant
 (e.g., glycerin). As another example, the formulation may contain from
 about 4 percent, by weight, of the humectant (e.g., glycerin).
 The aqueous alcoholic base contains water and an alcohol component.
 Generally speaking, the alcohol component may be selected from methanol,
 ethanol, propanol, isopropanol, butanol, t-butanol, 2-butanol, pentanol,
 hexanol, and mixtures of these alcohols. In an aspect of the invention,
 the alcoholic base may contain from about 20 to about 90 percent, by
 weight of the alcohol component and from about 1 to about 80 percent, by
 weight, water.
 It is contemplated that other materials may be added to the aqueous
 alcoholic base. For example, the base may further include disinfectants,
 antiseptics, surfactants, aqueous-alcohol miscible emollients,
 preservatives, viscosity modifiers, thickeners, colorants, fragrances,
 and/or buffers and/or pH control agents.
 In an aspect of the invention, it is desirable that the liquid
 antimicrobial, skin moisturizing formulation be in the form of a gel or
 material having a gel-like or thickened consistency. Desirably, the
 formulation will have a viscosity in the range of from about 2,000 to
 about 100,000 centipoise. More desirably, the formulation will have a
 viscosity in the range of from about 10,000 to about 60,000 centipoise.
 Even more desirably, the formulation will have a viscosity in the range of
 from about 15,000 to about 40,000 centipoise. The viscosity may be
 adjusted so the formulation may be dispensed from any variety of
 conventional dispensers for such gel-like or thickened materials. Of
 course, the formulation may be in the form of a low viscosity free-flowing
 liquid such as, for example, a liquid that could be dispensed from
 sprayers or spray bottles (e.g., piston-pump type sprayers), squeeze
 bottles, sponge bottles or similar applicators.
 The present invention also encompasses a wet wipe impregnated with a liquid
 antimicrobial, skin moisturizing formulation of the type described above.
 The wet wipe substrate is a permeable sheet such as, for example, a
 nonwoven fabric, woven fabric, knit fabric and combinations thereof. The
 nonwoven fabric may be a spunbonded web, a web of meltblown fibers, a
 bonded carded web, a hydraulically entangled web or the like. If the
 nonwoven fabric contains meltblown fibers, the meltblown fibers may be or
 may include meltblown microfibers.
 The present invention also encompasses a method of moisturizing and/or
 disinfecting the skin by applying a liquid antimicrobial, skin
 moisturizing formulation of the type described above. The method may
 include the step of applying the formulation utilizing a wet wipe
 impregnated with the formulation.

DETAILED DESCRIPTION
 As used herein, the term "emollient" refers to a liquid that soften or
 soothe the skin. Emollient are generally hydrophobic materials including,
 but not limited to silicones and alkyl substituted polysiloxane polymers,
 petrolatum, mineral oils, animal and vegetable oils and fats, fatty acid
 esters derived from fatty acids or fatty alcohols, mixtures of hydrocarbon
 materials that resemble petrolatum in appearance and consistency. Some
 emollients may be skin protectants as defined by the FDA Skin Protectant
 monograph. Examples of emollients in this category include dimethicone and
 petrolatum.
 As used herein, the term "skin moisturizing" refers to the action of a
 material which provides a relatively sustained increase in the level of
 skin hydration after one or more applications. Such relatively sustained
 increase in skin hydration may be for a period of up to several hours. The
 level of skin hydration may be determined by measuring skin conductance
 utilizing, for example, a Skicon-200 Conductance Meter.
 As used herein, the term, "antimicrobial" refers to a substance that kills
 or inhibits the growth of microorganisms. Exemplary antimicrobial
 materials include alcohols having from one to about 6 or 7 carbon atoms
 per molecule. Alcohols exhibit antimicrobial properties when used at
 sufficiently high concentrations and/or with viscosity increasing agents
 (e.g., thickeners) to increase the residence time of the alcohol on the
 skin or on a surface where the alcohol is delivered.
 As used herein, the term "particulate" refers to a small, discrete,
 grain-like portion of material. Examples of particulates include, but are
 not limited to powders, dusts, grains and the like. The term also
 encompasses agglomerations of particulates as well as small beads,
 capsules or other materials.
 As used herein, the term "delivery material" refers to a substance that
 encapsulates or entraps a liquid until it is ready for use and then
 releases at least a portion of the liquid at once or over a desired period
 of time. Delivery materials that encapsulate include, for example,
 capsules, hollow beads, hollow shells, spheres and the like having one or
 more layers that surround a core of liquid. When the shell or exterior
 wall(s)of the delivery material is broken, the liquid is dispersed.
 Delivery materials that entrap include, for example, talcs, starches,
 clays, and polymeric entrapment materials. Generally speaking, such
 delivery materials adsorb and hold liquid in a network of voids and
 interstices. The liquid is thought to be released utilizing one or more of
 the following mechanisms: wicking, migration, evaporation, mechanical
 disruption of the delivery material, and displacement. It is contemplated
 that various combinations of delivery materials may be used together in
 the formulations of the present invention. It is also contemplated that
 the same or different delivery materials may be used to encapsulate or
 entrap the same or different emollients and that such delivery materials
 may be used in the formulations of the present invention. For example, a
 first delivery material may contain a first emollient and a second
 delivery material containing a second emollient may each be added to a
 formulation.
 As used herein, the term "nonwoven web" refers to a web that has a
 structure of individual fibers or filaments which are interlaid, but not
 in an identifiable repeating manner. Nonwoven webs have been, in the past,
 formed by a variety of processes known to those skilled in the art such
 as, for example, meltblowing, spunbonding, wet-forming and various bonded
 carded web processes.
 As used herein, the term "spunbonded web" refers to a web of small diameter
 fibers and/or filaments which are formed by extruding a molten
 thermoplastic material as filaments from a plurality of fine, usually
 circular, capillaries in a spinnerette with the diameter of the extruded
 filaments then being rapidly reduced, for example, by non-eductive or
 eductive fluid-drawing or other well known spunbonding mechanisms. The
 production of spunbonded nonwoven webs is illustrated in patents such as
 Appel, et al., U.S. Pat. No. 4,340,563.
 As used herein, the term "meltblown fibers" means fibers formed by
 extruding a molten thermoplastic material through a plurality of fine,
 usually circular, die capillaries as molten threads or filaments into a
 high-velocity gas (e.g. air) stream which attenuates the filaments of
 molten thermoplastic material to reduce their diameters, which may be to
 microfiber diameter. Thereafter, the meltblown fibers are carried by the
 high-velocity gas stream and are deposited on a collecting surface to form
 a web of randomly dispersed meltblown fibers. The meltblown process is
 well-known and is described in various patents and publications, including
 NRL Report 4364, "Manufacture of Super-Fine Organic Fibers" by V. A.
 Wendt, E. L. Boone, and C. D. Fluharty; NRL Report 5265, "An Improved
 Device for the Formation of Super-Fine Thermoplastic Fibers" by K. D.
 Lawrence, R. T. Lukas, and J. A. Young; and U.S. Pat. No. 3,849,241,
 issued Nov. 19, 1974, to Buntin, et al.
 As used herein, the term "microfibers" means small diameter fibers having
 an average diameter not greater than about 100 microns, for example,
 having a diameter of from about 0.5 microns to about 50 microns, more
 specifically microfibers may also have an average diameter of from about 1
 micron to about 20 microns. Microfibers having an average diameter of
 about 3 microns or less are commonly referred to as ultra-fine
 microfibers. A description of an exemplary process of making ultra-fine
 microfibers may be found in, for example, U.S. Pat. No. 5,213,881,
 entitled "A Nonwoven Web With Improved Barrier Properties".
 As used herein, the term "sheet" refers to a material that can be a woven
 fabric, knit fabric, nonwoven fabric or combination thereof.
 The present invention encompasses an liquid antimicrobial, skin
 moisturizing formulation. The formulation includes at least the following
 components: 1) an aqueous alcoholic base; 2) a humectant; 3) a particulate
 delivery material adapted to release an emollient when the formulation is
 applied to the skin; and 4) an emollient imiscible in the aqueous
 alcoholic base and contained by the particulate delivery material.
 Generally speaking, the emollient is a hydrophobic liquid that is imiscible
 in the aqueous alcoholic base. The emollient is generally also imiscible
 in the humectant component of the formulation. It is contemplated that the
 emollient may have some relatively low level of miscibility with the
 aqueous alcoholic base and/or humectant, depending on the type of
 emollient used. For example, alkyl substituted polysiloxane polymers
 and/or petrolatum may be imiscible in the aqueous alcoholic base while
 fatty acid ester emollients may have some relatively low level of
 miscibility but would still be generally regarded as imiscible.
 Using an emollient that is imiscible in the aqueous alcoholic base is
 advantageous when the emollient is entrapped or adsorbed in the delivery
 material. Generally speaking, if the surface energy of the emollient is
 similar to that of the delivery material and is lower than the surface
 energy of the aqueous alcoholic base, the emollient will tend to stay
 entrapped in the delivery material until the formulation is applied to the
 skin.
 The emollient may be one ore more alkyl substituted polysiloxane polymers
 (e.g., silicones), one or more liquid hydrocarbon emollients such as
 petrolatum and mineral oils of the type known in the art for use in
 cosmetic compositions. "Petrolatum" also includes mixtures of hydrocarbon
 materials which resemble petrolatum in appearance and consistency such as
 a mixture formed by melting substances such as paraffin wax or
 microcrystalline wax and the like with mineral oil. The emollient may be
 selected from vegetable and animal fats (e.g., lanolin, phospholipids and
 their derivatives. Desirably, the emollient is one or more alkyl
 substituted polysiloxane polymers. More desirably, the emollient is
 dimethicone or combinations of dimethicone and other alkyl substituted
 polysiloxane polymers. These dimethicone and polysiloxane materials will
 desirably have a viscosity in the range of 20 to 350 centipoise.
 If the emollient is one or more alkyl substituted polysiloxane polymers, it
 is contemplated that it may be blended or combined with one or more fatty
 acid ester emollients derived from fatty acids or fatty alcohols having
 from about 12 to 22 carbon atoms. Examples of such esters are methyl,
 isopropyl and butyl esters of fatty acids such as isopropyl palmitate,
 isopropyl myristate, isopropyl isostearate, isostearyl isostearate,
 diisopropyl sebacate, and propylene glycol dipelargonate, as well as
 2-ethylhexyl isononoate, 2-ethylhexyl stearate, C.sub.12 -C.sub.16 fatty
 alcohol lactates such as cetyl lactate and lauryl lactate, isopropyl
 lanolate, 2-ethylhexyl salicylate, oleyl myristate, oleyl stearate, oleyl
 oleate, hexyl laurate, isohexyl laurate and mixtures of the same.
 The particulate delivery material may be a finely divided material such as
 a powder-like material. The size of the particulates may vary from less
 than 1 micrometer (1 micron or 1 .mu.m) to about 1000 micrometers or about
 millimeter. Desirably, the delivery material will have a size ranging from
 about 5 to a few hundred micrometers. It is also desirable that the
 delivery material be readily dispersed in the aqueous alcoholic base. This
 may be accomplished by using particulate delivery materials having a
 relatively small size. It may also helpful to add viscosity modifiers or
 thickening agents to the aqueous alcoholic base to help reduce the
 tendency of the particulate delivery material to settle out.
 A feature of the invention is that the particulate delivery material holds
 or contains the emollient and then releases the emollient when the
 formulation is applied to the skin. The release of emollient may occur
 quickly as in the case of emollient encapsulated in capsules, hollow beads
 and/or shells. These materials are subject to mechanical disrupted or
 breakage during application. The release of emollient may be a controlled
 or sustained release as in the case of emollient entrapped in talc, clay,
 starches, and/or polymeric delivery materials. Release of emollient from
 such materials may occur through one or more of the following mechanisms:
 wicking, migration, evaporation, mechanical disruption of the delivery
 material, and displacement.
 For example, the particulate delivery material may be gel capsules, small
 plastic beads or spheres and/or similar bubble-like structures composed of
 a single or multiple layers that hold or surround the emollient. In
 another embodiment of the invention, the particulate delivery material may
 entrap the emollient. For example, the particulate delivery material may
 be adsorbent or high surface area materials such as certain starches,
 talcs, clays, metals, polymeric entrapment materials and the like.
 Desirably, the particulate delivery material is a polymeric entrapment
 material. These materials may be formed from a variety of polymers such
 as, for example, polyolefins, nylons, polyacrylics and the like. Exemplary
 polymeric entrapment materials include one or more materials having the
 CTFA designation acrylates copolymers. Exemplary acrylates copolymers may
 be characterized as cross-linked methacrylates appearing as a white,
 free-flowing powder. Suitable acrylates copolymers may be obtained from
 Advanced Polymer Systems of Redwood City, California, under the trademarks
 Microsponge.RTM. and Polytrap.RTM.. An exemplary material available under
 the Polytrap.RTM. trademark is a highly cross-linked polymethacrylate
 polymer in the form of an amorphous, free-flowing powder. The material has
 a powder-like structure. The smallest or primary units are individual
 particles of about 1 micrometer or less in size. These particles partially
 fuse to form agglomerates ranging in size from about 20 to 80 micrometers.
 These agglomerates may be held together by electrostatic forces and
 mechanical entanglement to form still larger aggregates or agglomerates.
 Such materials may be used to entrap useful levels of emollients for
 incorporation in the present formulations and may contain about 35 weight
 percent, based on the weight of the acrylates copolymer, of entrapped
 dimethicone. Another exemplary acrylates copolymer product is a
 Polytrap.RTM. 7100 macrobeads material containing about 35 weight percent,
 based on the weight of the acrylates copolymer, of entrapped dimethicone.
 This material is a highly cross-linked polymethacrylate copolymer in the
 form of approximately 200 micrometer spherical particles. These particles
 are described as being adapted to crumble readily as they are spread
 across the skin. These macrobead materials may desirably contain other
 levels (e.g., desirably higher levels) of dimethicone. For example, some
 materials may contain about 50 to about 75 weight percent, based on the
 weight of the acrylates copolymer, of entrapped dimethicone. Desirably,
 some materials may contain about 55 to about 65 weight percent, based on
 the weight of the acrylates copolymer, of entrapped dimethicone.
 An exemplary acrylates copolymer available under the Microsponge.RTM.
 trademark is a highly cross-linked polymethacrylate copolymer in the form
 of approximately 25 micrometer spherical particles. The material has a
 reported bulk density of about 0.57 g/cc.
 Description of useful particulate delivery materials may be found in, for
 example, U.S. Pat. No. 4,690,825 for "Method For Delivering An Active
 Ingredient By Controlled Time Release Utilizing A Novel Delivery Vehicle
 Which Can Be Prepared By A Process Utilizing The Active Ingredient As A
 Porogen" issued Sep. 1, 1987; U.S. Pat. No. RE 33,429 for
 "Lattice-Entrapped Emollient Moisturizer Composition" issued Nov. 6, 1990;
 and U.S. Pat. No. 5,145,675 for "Two Step Method For Preparation Of
 Controlled Release Formulations" issued Sep. 8, 1992, the contents of
 which are incorporated herein by reference.
 Particulate delivery materials are also described by Abrutyn, E. S. and
 Saxena, S. J., "Polymeric Controlled Release Topical Cosmetic
 Applications", Cosmetics & Toiletries, Vol. 107, No. 8, Pps. 65-70 (August
 1992); and Klein, W. L., and DiSapio, A. J., "Acrylates Copolymer: A
 Technique for Entrapping Cosmetic Additives", HAPPI magazine, Vol. 26, No.
 7 (July 1989). Generally speaking, the formulation will contain from about
 0.1 to about 5 percent, by weight, of the particulate delivery material
 containing the emollient. Relatively small amounts of particulate delivery
 material may be used if it is capable of containing and delivering
 relatively large amounts of emollient. On the other hand, relatively large
 amounts of particulate delivery material may be needed if it is capable of
 containing and delivering relatively small amounts of emollient. As an
 example, relatively small amounts of acrylates copolymer may be adequate
 while relatively large amounts of starch or talc may be needed to deliver
 the same level of emollient.
 While the loading of the emollient in the particulate delivery material
 will vary depending on the maximum liquid load for the particulate
 delivery material, it is generally thought that particulate delivery
 materials may contain from about 10 to about 80 weight percent, based on
 the weight of the particulate delivery material, of the emollient. This
 level may be at the lower end of the range for starches and talcs and may
 be at the upper end of the range for acrylates copolymers. For example,
 when certain agglomerated acrylates copolymers are used, they may be
 loaded with from about 35 to about 75 weight percent, based on the weight
 of the particulate delivery material, of the emollient. As another
 example, the particulate delivery material may contain about 50 to about
 70 weight percent, based on the weight of the particulate delivery
 material, of the emollient.
 The level of loading may be influenced by modifying the surface energy of
 the liquid loaded into the particulate delivery material. For example,
 some acrylates copolymer delivery materials have a surface energy in the
 range of 40 to 50 dynes per centimeter. An ingredient with a surface
 energy generally within that range generally wets the particulate and is
 adsorbed. If the surface energy of the liquid is much higher, it may be
 lowered by adding an surfactant.
 According to an aspect of the present invention, the emollient reduces the
 undesirable tactile attributes of the formulation that may be caused by
 the humectant component. For example, an alkyl substituted polysiloxane
 polymer emollient such as a dimethicone emollient will reduce the level of
 tacky or sticky sensation that may be caused by the glycerin humectant in
 the formulation. Although the inventor should not be held to any
 particular theory of operation, it is thought that the dimethicone
 emollient forms a layer at the surface of the glycerin which imparts a
 smooth or non-tacky feel when touched. The particulate delivery material
 may also help reduce the undesirable tactile attributes of the formulation
 that may be caused by the humectant component. For example, a fine,
 powdery particulate delivery material may help provide a smooth, silky
 feel. Talc may be useful as a delivery material which helps provide
 desirable tactile attributes. It is contemplated that talc or similar
 delivery materials may be blended with other particulate delivery
 materials such as, for example, acrylates copolymers.
 The humectant may be a water soluble polyhydric alcohol having from 2 to 3
 hydroxyl groups and blends thereof. Desirably, the humectant is glycerin.
 The amount of humectant in the formulation may vary depending on the level
 of moisturizing desired. Desirably, the level of humectant may range from
 about 1 to about 15 percent, by weight. For example, the formulation may
 contain from about 1 to about 5 percent, by weight, of the humectant
 (e.g., glycerin).
 The aqueous alcoholic base contains water and an alcohol component.
 Generally speaking, the alcohol component may be selected from methanol,
 ethanol, propanol, isopropanol, butanol, t-butanol, 2-butanol, pentanol,
 hexanol, and mixtures of these alcohols. Desirably, the alcohol component
 is ethanol. In an aspect of the invention, the alcoholic base may contain
 from about 20 to about 90 percent, by weight of the alcohol component and
 from about 1 to about 78.5 percent, by weight, water. In another aspect of
 the invention, the alcoholic base may contain from about 60 to about 90
 percent, by weight of the alcohol component and from about 1 to about 38.5
 percent, by weight, water.
 It is contemplated that other materials may be added to the aqueous
 alcoholic base. For example, the base may further include antimicrobials,
 disinfectants antiseptics, surfactants, aqueous-alcohol miscible
 emollients, preservatives, viscosity modifiers, thickeners, colorants,
 fragrances, and/or buffers and/or pH control agents.
 An exemplary thickening agent is an addition polymer of acrylic acid
 cross-linked with an unsaturated polyfunctional agent such as a poly-allyl
 ether of sucrose is employed. Such polymers are described in U.S. Pat.
 Nos. 2,798,053 and 3,133,865, have the CTFA (Cosmetic, Toiletry and
 Fragrance Association) adopted name of "Carbomer" and are commercially
 available under the tradenames CARBOMER.RTM. 934, 940 and 941 from B. F.
 Goodrich Chemicals Group of Cleveland, Ohio and under the tradenames
 ACRITAMER 934, 940 and 941 from R.I.T.A. Corporation of Crystal Lake, Ill.
 These polymers may be used in an amount which is sufficient to obtain a
 gelled composition of viscosity in the range of 10,000 to 100,000
 centipoise (10 to 100 pascal second) at 25.degree. C., and for pump
 dispenser use, preferably from about 10,000 to 50,000 centipoise (10 to 50
 pascal second), and most preferably, from about 10,000 to 20,000
 centipoise (10 to 20 pascal second), but not so much as to leave a sticky
 residue on the skin after the alcohol and water in the composition have
 evaporated. Typically up to about 2 weight percent of the total
 composition and desirably, up to about 0.7 weight percent of such a
 thickener is used.
 Other thickeners can be used to improve the gel obtained as well as the
 skin feel of the composition. For example, from about 0.1 to about 0.5,
 preferably 0.25, weight per cent of a hydroxypropyl guar gum (propylene
 glycol ether of guar gum) of higher molecular weight and higher degree of
 substitution such as JAGUAR HP-79 and HP-120 from Alcolac, Inc. of
 Baltimore, Md. can be used. Examples of other thickeners include Sepigel
 307 (polyacrylamide, c 13-14 isoparaffin and Laurth-7), and KLUCEL.RTM.
 99-HHF available from the Aqualon Division of Hercules, Inc., Wilmington,
 Del.
 Some thickening agents/thickeners may be affected by the high alcohol
 content of the formulation. In such case, a stabilizing agent and/or
 neutralizing agent that is compatible with the formulation may be added.
 Such stabilizing agents and/or neutralizing agents are known and their
 selection and use would be within the capability of one having ordinary
 skill in the art.
 The formulation may contain a small amount (e.g., less than about 1 weight
 percent) of one or more surfactants. Desirably, the surfactant is a
 nonionic surfactant. Anionic or amphoteric surfactants, including
 zwitterionic surfactants may be used where appropriate.
 Exemplary nonionic surfactants are polyethoxylated fatty alcohols of the
 formula R'O(CH.sub.2 CH.sub.2 O).sub.x H where R' is a hydrocarbon radical
 of from about 12 to 22 carbon atoms and x has a value of from about 2 to
 100 and more preferably, from about 2 to 25. The RO-- group in the formula
 can be derived from fatty alcohols having from about 12 to 22 carbon atoms
 such as lauryl, myristyl, cetyl, hexadecyl, stearyl, isostearyl,
 hydroxystearyl, oleyl, ricinoleyl, behenyl, and erucyl alcohols, and
 2-octadecanol. An example of such surfactants is ceteth-20 (cetyl ether of
 polyethylene oxide having an average of about 20 ethylene oxide units).
 This and other such nonionic surfactants are commercially available under
 the tradename "BRIJ" from ICI Americas, Inc. of Wilmington, Del.
 Other examples of nonionic surfactants are those typically used in
 cosmetics such as alkyl phenols with 6 to 12 carbon in the alkyl chain
 condensed with 2 to 25 moles of ethylene oxide; mono- and di-fatty acid
 esters of ethylene glycol wherein the fatty acid moiety contains from
 about 12 to 22 carbon atoms; fatty acid monoglycerides wherein the fatty
 acid moiety contains from about 12 to 22 carbon atoms; fatty acid esters
 of sorbitol sorbitan, polyoxyethlene sorbitol, and olyoxyethylene sorbitan
 where the fatty acid moiety contains from about 12 to 22 carbon atoms.
 Such surfactants are well known and many are commercially available.
 Exemplary formulations of some embodiments of the invention are given in
 Table 1. It should be understood that these formulations describe examples
 of ingredients and composition ranges and are not to be interpreted as
 limiting the invention to a particular ingredient or composition.
 TABLE 1
 Exemplary Formulations
 Percent Percent
 Composition Composition
 INGREDIENT (Broad Range) (Narrower Range)
 HUMECTANT
 Glycerin 1.0 to 15.0 1.0 to 5.0
 TICULATE
 DELIVERY MATERIAL
 Acrylates 0.1 to 5.0 1.0 to 2.5
 Copolymers
 EMOLLIENT
 % loading in particulate
 delivery material
 Dimethicone 10 to 80 40 to 70
 AQUEOUS ALCOHOLIC BASE to make up 100% to make up 100%
 Water 1 to 78.5 1 to 38.5
 Ethanol 20 to 90 60 to 80
 OTHER INGREDIENTS
 Carbomer .RTM. 940 0.0 to 1.0 0.0 to 0.5
 Triethanolamine 0.0 to 1.0 0.0 to 0.5
 Klucel .RTM. 99-HHF
 hydroxylpropyl cellulose 0.0 to 1.0 0.0 to 0.5
 Fragrance 0.0 to 1.0 0.0 to 0.5
 The present invention also encompasses a wet wipe impregnated with a liquid
 antimicrobial, skin moisturizing formulation of the type described above.
 The wet wipe substrate is a permeable sheet such as, for example, a
 nonwoven fabric, woven fabric, knit fabric and combinations thereof. The
 nonwoven fabric may be a spunbonded web, a web of meltblown fibers, a
 bonded carded web, a hydraulically entangled web or the like. If the
 nonwoven fabric contains meltblown fibers, the meltblown fibers may be or
 may include meltblown microfibers. Suitable wet wipes are disclosed in
 U.S. Pat. No. 4,904,524, issued Feb. 27, 1990, to Yoh; and U.S. Pat. No.
 5,656,361, issued Aug. 12, 1997, to Vogt et al., the contents of which are
 incorporated herein by reference.
 EXAMPLES
 Formulation
 The following examples describe liquid antimicrobial skin moisturizing
 formulations. Generally speaking, the ingredients are identified by their
 chemical name, CTFA name, or in some cases, by their trade names. The
 ingredients were combined by conventional mixing and/or soap formulating
 techniques. The Carbomer.RTM. 940 thickener was mixed into water until it
 was completely hydrated. This took approximately 40 minutes. The remaining
 ingredients, with the exception of triethanolamine, were added to the
 mixture one at a time and allowed to mix fully. Finally, the mixture was
 thickened by adding triethanolamine. The specific amounts of ingredients
 for the Skin Moisturization Evaluation are identified in Table 2.
 TABLE 2
 INGREDIENT Code W
 Ethyl Alcohol 60.00
 Polytrap .RTM. (35% dimethicone) 1.50
 glycerin 2.00
 Carbomer .RTM. 940 0.32
 triethanolamine 0.24
 fragrance 0.40
 water 35.54
 A series of liquid, antimicrobial skin moisturizing formulations were made
 utilizing an ethyl alcohol gel base utilizing the same formulating
 techniques described above. Amounts of ingredients in the ethyl alcohol
 gel base were similar to those listed in Table 2 except that the
 Polytrap.RTM. material and glycerin were not added. The percent
 compositions for the ethyl alcohol gel base formulation are shown in Table
 3
 TABLE 3
 Percent
 INGREDIENT Composition
 Ethyl Alcohol 65.00
 Carbomer .RTM. 940 0.32
 triethanolamine 0.24
 fragrance 0.40
 water 34.04
 Various combinations of humectants and emollient were added to this ethyl
 alcohol gel base including glycerin and a Polytrap.RTM. material
 containing 35 weight percent dimethicone. The various combinations are
 described in terms weight percent of ingredients added to the ethyl
 alcohol gel base. The additional ingredients for each of six test product
 codes are described in Table 4.
 TABLE 4
 Product
 Code Description of product
 Code 123 Ethyl Alcohol Gel base (see Table 3)
 Code 335 Ethyl Alcohol Gel base + 2% Polytrap .RTM. material
 {dimethicone (35%)}
 Code 472 Ethyl Alcohol Gel base + 2% glycerin
 Code 581 Ethyl Alcohol Gel base + 2% glycerin + 2% Polytrap .RTM.
 material {dimethicone (35%)}
 Skin Moisturization Evaluation
 It has been shown, most notably by Obata and Tagami [Obata, And Tagami, H.
 "A rapid in vitro test to assess skin moisturizers.", J. Soc. Cosmet.
 Chem., 41 235-241 (July/August, 1990)], that the ability of an alternating
 current to flow through the stratum corneum is an indirect measure of its
 water content.
 Skin conductance was measured with an lBS Skicon-200 Conductance Meter
 model number 03489 available from I.B.S., Ltd., Shizuuka-Ken, Japan. The
 conductance meter was equipped with an MT-8C probe from Measurement
 Technologies of Cincinnati, Ohio. The MT-8C probe has 8 pins evenly spaced
 in a circle about 16mm in circumference. These pins, of alternating
 polarities are spaced at about 2 mm. With the MT-8C probe, conductance is
 measured around a 16 mm ring and wet/dry/electrolyte effects are minimized
 by an averaging effect around the ring.
 The experimental equipment reported measurements of skin conductance in
 units of milliohms. These measurements represented the AC conductance 5
 seconds after placing the spring-loaded probe tip to the sample site
 (i.e., a marked portion of the forearm). The timing interval is believed
 to be sufficient for the electronic circuits to stabilize in response to
 the change in conductance but short enough not to be influenced by
 increased hydration at the probe tip due to its being occlusive and acting
 as a hindrance to the normal water loss at the test site.
 An experiment was conducted to compare the effects of four alcohol gel
 products on the stratum corneum overtime with multiple applications. The
 following alcohol gels were evaluated:

Product
 Code Description of product
 Code J Viragel .RTM., available from Veridien, Inc.
 Code W See description in Table 2
 Code G Sanigel .RTM., available from Central Solutions, Inc.
 Code B Purell .RTM. w/aloe, available from GoJo .RTM. Inc.
 Purell.RTM. with aloe contains approximately 62% ethyl alcohol, with
 smaller amounts of isopropyl alcohol, emollients and thickeners.
 Viragel.RTM. contains approximately 70% isopropyl alcohol with smaller
 amounts of propylene glycol, thickener and fragrance. Sanigel.RTM.
 contains approximately 69% ethyl alcohol 15 and smaller amounts of
 glycerin, thickener and fragrance.
 Four panelists were instructed to avoid using soap or any type of
 moisturizing products on the forearm area 24 hours prior to their first
 scheduled session. The subjects acclimated in a controlled room set at
 70.degree. F., 40%RH for 30 minutes. Upon acclimation, each subject had
 two 5 cm by 5 cm test sites outlined on their volar forearm using a
 standard template A series of baseline measurements were taken from each
 test site with the Skicon-200 Conductance Meter. Five conductance readings
 were taken in the 5 cm.times.5 cm test site and averaged. Five skin
 hydration readings per second for 2 minutes were taken and averaged. Test
 product was applied (0.1 mL) to each site in a randomly ordered sequence.
 The product was applied with a gloved hand using a quarter size circular
 motion. The time in which it took for the product to dry on the forearm
 was recorded. After the product dried, skin conductance measurements were
 taken at 1 minute and 10 minutes and then at 30 and 60 minutes The product
 was reapplied to the skin every 30 minutes, three times. During each
 session two products were evaluated. The testing was carried out for four
 consecutive days.
 The results depicted in FIG. 1 shows that the average 5 and 10 application
 conductance measurements taken 10 minutes after the last application on
 day 1 are lower than baseline for Code G (Sanigel.RTM.), slightly higher
 for B (Purell.RTM. w/aloe), but are much higher for Codes J (Viragel.RTM.)
 and W (New Formulation). This appears to indicate that Codes J and W
 increase skin moisture and Codes G and B do not increase skin moisture.
 The results depicted in FIGS. 2 and 3 show that the average 30 and 60
 minute conductance measurement taken after the 10.sup.th application on
 days 2 and 3 are lower than baseline for Code G and slightly higher for
 Code B and Code J. Code W is higher than baseline. Code W increases skin
 moisture for at least 60 minutes after the 10.sup.th application whereas
 Code J decreases significantly over this time frame. This appears to
 indicate that the glycerin in the formula is being retained in the skin
 which increases skin moisture.
 FIG. 4 depicts the baseline readings for each code over 4 days. Code W has
 the highest increase in baseline readings over four days. This appears to
 indicate that the product maintains moisture over a 24 hour time period.
 Codes J and C have the lowest baseline readings throughout the study. Code
 J (viragel.RTM.) has fairly low baseline readings from day to day.
 However, SkiCon measurements indicate that the product appears to increase
 skin conductance shortly after application. This would mean that the skin
 loses this moisture overnight. Code G's (Sanigel.RTM.) baseline
 measurements do not vary much from day to day.
 The skin conductance testing was carried out in a separate study for the
 alcohol gel formulations identified in Table 4. The study utilized the
 same equipment and test procedures as described above except that there
 were six panelists.
 The results of testing the formulations of Table 4 are reported in FIGS.
 5-9. The graphical representation of skin conductance data in FIGS. 5-9
 are grouped by day. Within each group are individual bars representing the
 skin conductance reading for a particular code. The individual bars within
 each group are arranged in sequence and represent (from left to right):
 Code 123, Code 335, Code 472, and Code 581. FIGS. 5 and 6 show the percent
 change from the day 1 baseline over five days. This data indicate that
 codes 472 and 581 (all containing glycerin) increase skin moisture over
 time. Although code 581 has the highest change, this may not be
 significant due to small sample size. The highest increase in moisture
 occurs on day five. This is thought to be caused by the numerous
 applications of product on the skin and the accumulation of glycerin in
 the stratum corneum. Codes 123 and 335 did not increase skin hydration
 readings over time. This data shows that products containing glycerin
 increase skin moisture. There appears to be a tendency for formulations
 containing acrylates copolymers products but not glycerin to dry the skin.
 FIG. 7 depicts the absolute baseline readings over five days. There is a
 steady increase in skin hydration from day to day for codes 472 and 581.
 Day five has the highest increase in skin hydration for all six codes.
 FIG. 8 depicts the change in readings form the morning baseline until
 thirty minutes after the .sub.10 th application. FIG. 9 depicts the
 overnight change in readings. Application of glycerin containing
 formulations increases the skin conductance readings during the day, while
 alcohol gels without glycerin result in lower readings (corresponding to
 drier skin). There is also a recovery overnight in the opposite direction.
 High moisture levels are somewhat lost, while dry skin picks up moisture.
 For glycerin, the magnitude of recovery creates an overall increase
 throughout the five days.
 There appears to be a greater drop in skin conductance during the day with
 formulations containing dimethicone emollients. This appears to be an
 artifact of the test method caused by dimethicone acting as an insulator
 against the electrical measurement of the skin conductance meter. With
 normal shedding of skin and dissipation of the dimethicone layer
 overnight, this apparent insulating effect is lost and baseline readings
 are consistent.
 Tactile Testing--Paired Comparisons
 The effects of seven formulations were evaluated in a paired comparison use
 test. Six formulations differed in glycerin composition and the presence
 or absence of an emollient ingredient that reduced unpleasant tactile
 sensations. The specific amounts of ingredients for the Tactile
 Testing--Paired Comparisons are identified in Table 5.
 TABLE 5
 Percent Composition
 Code Code Code Code Code Code
 781 525 245 337 123 473
 Ethyl Alcohol 65.00 65.00 65.00 65.00 65.00 65.00
 Polytrap .RTM. 0.00 2.00 0.00 2.00 0.00 2.00
 (35% Dimethicone)
 Carbomer .RTM. 940 0.32 0.32 0.32 0.32 0.32 0.32
 triethanolamine 0.24 0.24 0.24 0.24 0.24 0.24
 fragrance 0.40 0.40 0.40 0.40 0.40 0.40
 water 26.04 24.04 30.04 28.04 32.04 30.04
 glycerin 8.00 8.00 4.00 4.00 2.00 2.00
 The Viragel.RTM. product utilized in this study contained approximately 70%
 ethyl alcohol with smaller amounts of propylene glycol, thickener and
 fragrance. The Viragel.RTM. was 20 labeled as Code 684.
 The four product comparisons evaluated in this study were as follows:
 Comparison 1 Code 781 (2% Glycerin)
 Code 525 (2% Glycerin+emollient)
 Comparison 2 Code 245 (4% Glycerin)
 Code 337 (4% Glycerin+emollient)
 Comparison 3 Code 123 (8% Glycerin)
 Code 473 (8% Glycerin+emollient)
 Comparison 4 Viragel.RTM.--Code 684
 Code 337 (4% Glycerin+emollient)
 Nineteen panelists participated in this study. They were instructed to wash
 their hands three times with 1 ml of Triangle Lotion Soap prior to the
 application of test product. This was done to remove any dirt or
 impurities that may have been on the skin. A one (1) mL portion of test
 product was injected onto the palm of each panelist's hand by the study
 moderator. Panelists were asked to massage the product into the skin until
 absorbed. Once absorbed, the panelists made an initial tackiness
 evaluation of their skin. Panelists then waited three minutes and made a
 final evaluation.
 The panelists washed their hands in between evaluations to remove prior
 product. The comparative hand gel was then injected onto the palm of their
 hand and the procedure was repeated At this time, the panelists were asked
 to determine which of the two products felt tackier on their skin and by
 how much. A ten point rating scale was used to determine the degree of
 tackiness detected with one (1) being the smallest level of difference and
 ten (10) being the greatest level of difference. The results from this
 study are shown in Table 6 and in FIGS. 9 and 10.
 TABLE 6
 Tactile Testing-Paired Comparisons
 no no
 no
 781 525 245 337 diff 123 473 diff 684
 337 diff
 Which product feels tackier on your hands?
 Initial Rating 84% 16% 90% 5% 5% 95% 5% 95%
 5%
 3 Minute Rating 95% 5% 95% 5% 90% 5% 5% 84$
 11% 5%
 How much tackier does this product feel?
 Initial Rating 7 6 7 6
 3 Minute Rating 7 6 6 5
 Rating Scale
 1=No difference.
 3=Very small difference, not confident, someone could miss it.
 5=Slight difference, confident about judgment.
 7=Moderate difference, easy to detect, confident.
 9=Very large difference, very easy to detect, memorable.
 FIG. 9 shows the initial rating of the panelists. FIG. 10 shows the rating
 of the panelists after 3 minutes. In FIGS. 9 and 10, it should be noted
 that the products containing the emollient entrapped in the particulate
 delivery material were labeled with a percentage level of glycerin
 followed by the term "APS Glycerin".
 Tactile Testing--After Feel
 A test was conducted to evaluate the tackiness of two of the product codes
 described above to determine the effect of the emollient. The product
 codes tested both contained 4& glycerin. Code 245 lacked an emollient.
 Code 337 contained 2% of Polytrap.RTM. acrylates copolymers loaded with 35
 weight percent, based on the weight of the Polytrap.RTM. material of
 dimethicone emollient.
 Six panelists participated in this study. They followed the following test
 procedure:
 1. The panelists were instructed to wash their hands with 1 ml of
 Triangle.TM. lotion soap (available from Kimberly-Clark Corporation) prior
 to the application of test product.
 2. 1 ml of test product was injected onto the palm of the panelist's hand.
 3. While still wet, the panelists generated a list of attributes describing
 the initial feel of the test product.
 4. Once the product absorbed into the skin, the panelists generated a list
 of attributes describing the after feel of the test product.
 5. The panelists timed and recorded how long the product remained tacky.
 6. The procedure was repeated using the second test product. The products
 were random sorted to reduce variability.
 An average period of time during which tackiness was perceived was reported
 for each code.
 Code 337 (Glycerin+Dimethicone)=1 minute of tackiness.
 Code 245 (Glycerin)=19 minutes of tackiness.
 Code 337--Attributes
 Initial Feel (while wet)--cool, gritty, pasty, smooth, slimy.
 After Feel (while dry)--cool, moisturized, smooth, silky, powdery.
 Code 245--Attributes
 Initial Feel (while wet)--cool, sticky, pasty, smooth, slimy.
 After Feel (while dry)--cool, moisturized but still sticky, tacky, gummy,
 pasty, slimy, gluey.
 While the present invention has been described in connection with certain
 embodiments, it is to be understood that the subject matter encompassed by
 way of the present invention is not to be limited to those specific
 embodiments. On the contrary, it is intended for the subject matter of the
 invention to include all alternatives, modifications and equivalents as
 can be included within the spirit and scope of the following claims.