MXPA00012315A - Disposable absorbent article containing an essential oil - Google Patents

Abstract

The invention relates to disposable absorbent articles containing an additive to control odors associated with bodily fluids. The invention is particularly useful in articles used to manage urine and menstrual fluids. The single additive provides both a pleasant aroma and antimicrobial activity.

Description

DISPOSABLE ABSORBENT ARTICLE CONTAINING AN ESSENTIAL OIL FIELD OF THE INVENTION The present invention relates to a disposable absorbent article containing an additive that emits fragrance and inhibits microbes, and methods for making same. The additives are essential oils and / or derivatives thereof.

BACKGROUND OF THE INVENTION There are two common forms of disposable items that are designed to absorb menstrual fluids discharged from a woman's cervix. The first article is intended to be completely inserted into the vaginal canal and placed near or against the cervical cavity. These items are commonly referred to as tampons for menstruation or simply tampons. Some of the disadvantages related to tampons are the following: they can be attributed excessive vaginal drying, they have been associated with toxic shock syndrome, they can be uncomfortable to insert and remove, especially on days of light flow, they have limited absorption capacity, according to the regulations established by the United States Food and Drug Administration.

The second article widely known and used to accumulate menstrual fluids is the sanitary napkin. This product is designed to be used externally to the vagina. Sanitary pads can also be used to absorb urine, due to the size and placement against the perineum. The product can be fixed to the crotch of the underwear, fix directly to the vulvar region with adhesives to the body, and also used partially or totally between the labia minora and major. Many consumers choose to use external absorbent articles because of their concern about toxic shock syndrome, the difficulty of inserting and removing tampons, the difficulty of using tampons, and the need for greater absorption capacity than that available from tampons. . However, as with tampons, there are disadvantages that have been manifested by users who rely on external absorbent articles due to their fluid handling needs. A disadvantage observed in external sanitary napkins is their association with odors. Menstrual fluid contains a variety of substances that contain proteins and lipids. The microbial action on proteins has been recognized as a source of bad odor. Urine is another fluid that can be absorbed through sanitary protection products, and microbial activity can form ammonia from urea in excreted urine. Users complain that they do not feel "fresh" during their period, and therefore, they look for products that claim to control odor emissions. There have been a number of technologies developed to control odors associated with body fluids; particularly those attributed to perspiration, menstrual fluid degradation products, urine degradation products and various urine odors. Almost all technologies can be placed in three main subcategories. The first is the use of auxiliary materials to absorb or absorb volatile odors in an effort to restrict their release to the environment surrounding the user. The materials or compositions that adsorb and / or absorb volatile odors include sodium bicarbonate, sodium salts or ethylenediamine tetraacetic acid (EDTA), activated carbon, zeolites and mixtures of sodium bicarbonate, EDTA, and activated carbon. These methods are described in the U.S. Patents. numbers 4,237,591 and 5,306,487. The second is the use of disguising materials, such as perfumes, and the third is the use of substances to inhibit the formation of body fluid degradation products. The patent of E.U.A. 5,733,272 discloses absorbent articles containing moisture activated encapsulated perfume compositions and odor controlling agents, including antimicrobial compounds. So far, the discussion has highlighted technologies that are believed to resolve bad odors either directly by inhibiting microbial activity, thus decreasing the level of products of urine and menstruation degradation, or indirectly by suppressing or overcoming the odors that already exist.

BRIEF DESCRIPTION OF THE INVENTION The object of the present invention is to use an individual additive in disposable absorbent articles to provide a pleasant aroma and inhibit microbial growth. The individual additive is an essential oil, derivative or variation thereof. According to one embodiment of the present invention, a disposable absorbent article containing an essential oil in an amount effective to provide a pleasant aroma and inhibit microbial growth is provided. According to a second embodiment of the present invention, there is provided a method for making a disposable absorbent article containing an essential oil in an amount effective to provide a pleasant aroma and inhibit microbial growth comprising: (a) providing an absorbent material; (b) provide a material permeable to liquid; (c) provide a liquid impervious material; (d) enclosing the absorbent material with the liquid-permeable material and the liquid-impervious material; (e) contacting at least one of the absorbent material, the liquid permeable material, the liquid impervious material, or a combination thereof with an essential oil.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disposable absorbent article containing one or more essential oils. Essential oils are highly concentrated volatile liquids that originate from an individual botanical source. A typical essential oil is a complex mixture of alcohols, aldehydes, esters, ketones, oxides, phenols and terpenes. The essential oils can be extracted by steam distillation, and other known techniques, from a variety of plant components including but not limited to roots, leaves, bark, flowers and pulp. The majority of plants that produce oil are represented by 90 species, and these are derived from approximately 30 different plant families. The present invention provides an absorbent article containing one or more essential oils in an effective amount to provide two functions: to emit a pleasant aroma and to inhibit microbial growth. Rosemary oil, clove oil, ginger oil, turmeric oil, chamomile oil, lemon grass oil, thyme oil, yarrow oil, thulasi oil, sclarea sage oil, cedar oil (hinoki) and derivatives , variations and mixtures thereof, all suitable for use as the essential oil. Synthetic forms of the oils described above can also be used in the present invention. The preferred essential oil is rosemary oil, which is commercially available from Lorann Oils.

Probably, most of the bad odors attributed to body fluids are the result of bacteria that degrade components that reside in body fluids. Bacteria can transform phospholipids into amines and fatty acids, and urea from urine into ammonia. For example, rosemary oil is an effective inhibitor of a number of gram positive and gram negative bacteria, such as, but not limited to, Staphylococcus aureus, Eschericia coli, and Pseudomonas aeruginosa. In addition to its inhibitory effect on bacteria, rosemary oil also has an inhibitory effect on a variety of fungi and yeast. Of particular interest for feminine hygiene, it has been seen that rosemary oil inhibits the growth of Candida albicans. In addition to its antimicrobial activity, rosemary oil emits a camphorate smell similar to pine. In this way, a synergistic odor control is achieved since the rosemary oil inhibits the microbial growth that degrades the components of body fluids and provides a pleasant aroma. The effectiveness of an essential oil as a fragrance can be determined by collecting organoleptic data from a panel presented with a series of samples of absorbent articles containing increasing concentrations of essential oil. Samples are then evaluated in a variety of environments, including but not limited to, before use and during use. The panelists are asked a series of questions regarding their perceptions of the effectiveness of the essential oil, in various amounts added, to provide an aroma.

Test methods to determine the amount of essential oil necessary to inhibit microbial growth include the following: analytical methods used to investigate microbial growth in the presence of essential oil, and analytical / organoleptic methods employed to investigate the level of malodor degradation products generated by microbial activity in cervical and urethral discharge. As used herein, "inhibition" means substantially maintaining an existing microbial colony by preventing the further growth of microbes. The inhibition does not require the destruction of existing microbes or a reduction in the size of the colony, although this is a possible result. A test method that can be used to determine the microbial inhibition properties of essential oils is the zone of inhibition test. Another useful test method is the Durham Fusion test. Those skilled in the art are related to other test methods in the microbiology community that can be used to determine microbial inhibition as described in the present invention. In general, the amount of essential oil used in the absorbent article is between about 0.1 and about 8 weight percent, preferably between about 0.2 and about 4 percent by weight, and preferably between about 0.5 and about 1.5 weight percent. Due to the relatively high volatility of essential oils, preferably additional binder materials or mechanisms are used to reduce premature loss of the essential oil once it has been added to the disposable absorbent article. (If combination means are used, then the level can be adjusted to produce a similar scale of addition available on the surface after the migration has occurred). The disposable absorbent article of the present invention may have a plurality of forms including, but not limited to, sanitary napkins, tampons, diapers, surgical gowns, bed sheets, incontinence products, and wipes. The present invention is particularly advantageous for articles designed to handle cervical and urethral discharge. As used herein, and throughout the text, sanitary napkins means any feminine hygiene product used externally to the vagina. Essential oils can be added to any of the elements used to manufacture disposable absorbent articles, during their individual manufacture or during their configuration in the same article, or added to the final product once made from the elements. A method for incorporating essential oils into the articles is by combining the essential oils with a base polymer and then forming a film or fiber from the mixture. These films or fibers can be used to form the elements used in the manufacture of disposable absorbent articles. Combined additives in polymers, which then partially migrate to the surface of the solidified materials, are commonly referred to as "modifying agents". Modifying agents are known in the art to be useful for altering the surface of a material. A representative and non-limiting list of uses for modifying agents includes making the surface smoother, protecting the polymer against degradation, making the surface wettable and making the surface peelable, as used in the molding activity. A benefit of combining the essential oil additives with a base polymer is to reduce the amount of additive loss, or to prolong the time elapsed before the effective levels of essential oils decrease, due to the migration and total separation of the base polymer. is required. Another method to add essential oils to materials used in disposable absorbent articles, is to apply the essential oils to a finished product, usually through coating means. Simplicity and efficiency are two benefits of using coating techniques. Coating means that can be used suitably in the present invention include, but are not limited to, dipping, slotting, spraying, melt blowing, control coating and swirling. Sanitary pads are commercially available in multiple sizes and shapes, and may vary according to individual needs. Without limitation, the common names for the variety of sanitary napkin products for external use include panty-protectors, full-size and ultra-thin pads. Most sanitary napkins are either rectangular or hourglass shaped to fit in the crotch of underwear. Most of the products are fixed directly to the underclothes of a wearer, and they make intimate contact with the perineum when the underwear is put on. Alternatively, sanitary napkins can be fixed directly to the body with adhesives that adhere to the body, or held in place against the body by the pressures applied by the lips. Many of the increasing changes that have evolved in the development of new sanitary napkins, are aimed at improving the protection of the products. Compressive forces acting on the pads from body position and activity can distort the pad in the vicinity of the vaginal opening, resulting in a limited area for the fluid to contact the product when it leaves the vaginal opening. Therefore, lateral extensions, commonly referred to as wings, accompany many products in an effort to reduce spillage that may occur due to reduced area. The lateral extensions also act to keep the sanitary towel in the place where it was originally placed. The side extensions can be flexible and rigid, may or may not contain adhesive, may be folded around the hidden side of the undergarment, may be attached to the hidden side of the undergarment, or may be held against or secured to the body. Sanitary napkins usually contain two side extensions, but one skilled in the art would recognize that more than two side extensions can be used to improve the performance of a product. Normally, sanitary napkins are packaged loosely in a first package, such as a box or bag, and can have a second package that allows the consumer to transport individual products and protect them from any unwanted environmental disturbance. Individually packaged sanitary pads are often folded and then wrapped to facilitate comfort and discretion to transport the products. The products and methods of medical products folded and wrapped individually, are described in the patents of E.U.A. numbers 4,556,146 and 4,917,675; which are incorporated herein by reference. Normally, sanitary napkins are made of a number of separate items. A simple configuration would include the following elements: a material permeable to liquid, which represents the surface that makes contact with the body; a material impervious to liquid, which represents a barrier such as the opposite surface and an absorbent material or combination of absorbent materials contained between the two materials defining the surface. Adhesives can be added, with or without the presence of heat and pressure, to join the separated elements together. Adhesives can also be applied to the external surfaces of the product, either to attach to the underwear or directly to the body. Optionally, a layer or transfer material can be placed between the liquid permeable material and the absorbent material to improve the transfer of fluid to the absorbent materials. The above is intended to describe the basic elements contained within the majority of commercially available sanitary napkins; however, the present invention is not limited to disposable absorbent articles comprising the described elements. The technique is full of many additional technologies aimed at improving the performance and comfort of sanitary napkins, which would not alter the usefulness of the present invention. The liquid-permeable material can be a non-woven fabric, such ^ as a fabric linked by spinning; a thermally bonded fabric, a fabric joined by resin and the like; an apertured polymer film such as DRI-WEAVE commercially available from Procter and Gamble Company, and the like; or any other suitable coating surface, which is capable of allowing the fluid to penetrate and which is conveniently used against the perineum. The * fibrous structures can be coated with essential oils, or a solution of 10 essential oils, as the individual fibers are spun, or during or after making a non-woven structure with the fibers. The polymeric films can be coated with essential oils through any number of methods known to one skilled in the art. The preferred material to use as the surface that makes contact with the body is a non-material tissue. After the menstrual fluid or urine makes contact with the W cover the sanitary towel, the fluid is transferred from the cover material to the absorbent materials for sto. This may include the use of * an additional transfer layer to facilitate the kinetics of this step. A •? 20 list of representative and non-limiting materials useful as the absorbent, includes cellulosic fibers, such as wood pulp and cotton pulp; synthetic fibers, such as polyesters and polyolefins; superabsorbent polymers, such as polyacrylic acid and the like. Another unexpected benefit of the present invention is that it has been found that essential oils can be added to superabsorbent polymers without significant premature swelling of the polymers. Preferably, the structure includes wood pulp and about 5 to 80% meltable, thermoplastic fibers. As with roofing materials, essential oils can be added to absorbent materials during their manufacture. To prevent any fluid absorbed from spilling from the center of the sanitary napkin and towards the body or clothing, a liquid impervious material is added as a barrier. Useful barriers include, without limitation, polymeric films or coatings, such as polyolefins (eg, polyethylene and polypropylene), polyvinyls (eg, polyvinyl acetate, polyvinyl chloride, and polyvinylidene chloride), copolymers (eg, ethylene- vinyl acetate), and combinations or laminations of one or more of the above polymers; structures repellent to body fluids, such as nonwoven films, with openings, and repellent fiber layers integrated in the core layer of the absorbent materials. Preferred barriers include polypropylene and nonwoven materials repellent to body fluids. The most preferred barrier is constructed of polypropylene films. Without limitation, two methods for applying essential oils to the preferred barrier materials are by external coating of the materials, or by combination of essential oils before exclusion of fiber or film, after which the essential oils will migrate to the surface of the fibers. materials.

Adhesives are often included in the construction of sanitary napkins to join the multiple elements described above. Placement adhesive can also be applied to the impermeable barrier material, allowing f the sanitary napkin to be attached to the crotch of the underwear. To eliminate the space between the body and the sanitary napkin, there are also innovations that describe methods to use adhesives on portions of the liquid-permeable surface to attach the sanitary napkins directly to the perineum. A sanitary towel that adheres directly to the body is described in the patent =: from E.U.A. No. 5,658,270, incorporated herein by reference. The f 10 adhesives are excellent vehicles for essential oils. The additive can be easily dispersed in many types of adhesive, such as hot melt materials and hot melt materials. The use of adhesives as a vehicle, can improve the level of addition and placement of essential oils. The adhesives also serve as binder material that can reduce the amount of essential oils lost before use. A representative and non-limiting list of materials useful as construction or placement adhesives includes acrylics, hot melt materials based on starch, adhesives based on vinyl aromatic hydrocarbon block copolymers * and one or more conjugated dienes or hydrogenated aliphatic blocks, acids ? Polylactics, polyolefins based on hot melt materials such as amorphous alpha polyolefins, which may consist of one or more of the following monomers: propylene, ethylene, butene and hexane; hot melt materials based on low density polyethylene or low density polyethylene copolymers including ethylene-vinyl acetate, methyl acrylate, n-butyl acrylate and acrylic acid. Traditional setting adhesives that are known in the art are based on styrenic block copolymers such as • which are described in the patents of E.U.A. Nos. 5,149,741; 5,143,968; and 5,057,571. It is also possible that the material used to wrap individual products contains essential oils. Typically, the wrapping material is constructed either with polyolefin films, such as polypropylene, or with a paper form. A method to use the material of • 10 wrapping to apply essential oils to the sanitary napkin, is to coat the paper or polymeric film with known techniques, such as spraying, slit coating, or extrusion. The essential oils can then be transferred or migrated to the same sanitary napkin during the packaging procedure, or at any time before the consumer opens the packaged product individually. So far, the description has focused on sanitary napkins, most elemental features that can be included in their construction, and methods for adding essential oils to one or more of the individual elements. Essential oils can be added to sanitary napkins during its manufacture, or to the final product. The addition of essential oils during the manufacture of the article is the most preferred embodiment method in the present invention. This method can be accomplished through a number of techniques, including but not limited to spraying, slot coating, transfer coating, solid gravimetric feeders, through placement adhesives and building adhesives, and dip coating. Preferably, the essential oils are applied by spraying to the sanitary napkin during manufacture. 5 Essential oils can also be added to tampons, and to other disposable absorbent articles used internally. According to the techniques for incorporating essential oils into articles for external use, there are multiple methods suitable for the present invention, which = include but are not limited to adding essential oils to an element used to make tampons, add essential oils to a tampon during manufacture, and add essential oils after manufacture. Most tampons are constructed with absorbent fibers, such as cotton and viscose rayon, and the like. Optionally, the tampons may have a cover material on the outer surface to provide ease of insertion and removal, and also to reduce fiber detachment during use in the vaginal canal. A representative and non-limiting list of useful materials such as the cover, f includes apertured polymeric films, non-woven materials with polyester fibers, polyolefin fibers, double component fibers and the like; and others ? materials that will allow the fluid to pass through and into the material absorbent content by the cover. The patents of E.U.A. Nos. 4,294,253 and 4,642,108 describe tampon constructions and manufacturing methods.

Preferably, the essential oils are added to the cover material of the buffer. The technique for adding the essential oils to the cover may be any known, such as dipping, slotting, spraying, meltblowing, control coating and swirling. Another disposable absorbent article that is suitable for the present invention are small cloths or towels. Normally, the cloths have the form of a fibrous mesh constructed from a single layer of fibers, or multiple layers. The fibers can be woven or non-woven by = nature Preferably, the construction is a non-woven fiber made by splicing, meltblowing or combination thereof. A representative and non-limiting list of materials useful for manufacturing non-woven fibers is polyolefins, polyesters, acrylics and cotton. Cloths are used for numerous fluid handling purposes, including but not limited to during baby diaper changes, during article handling changes. menstruation, after urination, after bowel evacuation and after intercourse. Those skilled in the art will readily appreciate that a cloth containing an effective amount of essential oil to provide a pleasant aroma and inhibit microbial growth is beneficial to * purposes mentioned above. *, 20 In the following examples, a series of essential oils were subjected to the zone of inhibition test with a variety of bacteria as follows. The selected bacteria, as shown below in Table 1, was added uniformly to a medium such as blood or nutrient agar. An essential oil was added to a small stainless steel cylinder inserted into the agar, and incubated overnight. The size of the bacteria-free zones around the cylinders was then measured. Normally, multiple cylinders with different agent levels were used. Table 1 shows the results of a number of essential oils when tested with different bacterial test cultures.

TABLE 1 Zone of inhibition A series of essential oils were also subjected to the Durham fusion tube test by filtering a variety of bacteria. The tests were done as follows. Incumbent agar tubes were inoculated with the desired culture, and a measured amount of essential oil extracted with hexane (i.e., 0.1 ml) was placed in a Durham melting tube (2 mm internal diameter). The Durham tube was introduced into the inclined agar tube at a 30 ° angle so that the vapors emerging from the tube covered the surface of the agar slant tube. Table 2 shows the percentage of inhibition of the volatile component of selected essential oils after 48 hours of residence in the inoculated agar inclined tube. Tables 3 and 4 show the minimum concentrations for inhibition for Hinoki oil and yarrow oil, using the Durham fusion tube method.

TABLE 2 Durham fusion test Key inhibition gradient: = 0% inhibition at start = 25% inhibition ++ = 50% inhibition +++ 75% inhibition ++++ 100% inhibition TABLE 3 Hinoki oil: Minimal concentrations of inhibition TABLE 4 Yarrow oil: Minimum concentrations of inhibition The invention has been illustrated by, but is not intended to be limited to, the foregoing description and examples. The scope of the invention will be determined by the claims appended thereto.

Claims (18)

NOVELTY OF THE INVENTION CLAIMS

1. - A disposable absorbent article containing an effective amount of essential oil to provide a scent and inhibit microbial growth, wherein the essential oil is selected from the group consisting of rosemary oil, clove oil, ginger oil, turmeric oil, chamomile oil, lemongrass oil, thyme oil, yarrow oil, thulasi oil, sclarea sage oil, cedar oil (hinoki) and mixtures thereof.

2. The disposable absorbent article according to claim 1, further characterized in that the essential oil is rosemary oil.

3. The disposable absorbent article according to claim 1, further characterized in that the amount of essential oil is from about 0.1 to about 8.0 weight percent.

4. The disposable absorbent article according to claim 1, further characterized in that the essential oil is added to the disposable absorbent article during its manufacture.

5. The disposable absorbent article according to claim 1, further characterized in that the article is defined as sanitary napkins, tampons, or cloths.

6. - The disposable absorbent article according to claim 1, further characterized in that any of the elements used to make the article is combined with essential oil before • manufacture of the disposable absorbent article.

7. The disposable absorbent article according to claim 6, further characterized in that the essential oil is contained within adhesives used to join a plurality of elements that make up the article.

8. The disposable absorbent article in accordance with the • Claim 10, further characterized in that the essential oil is contained within adhesives used to secure the article to the underwear.

9. The disposable absorbent article according to claim 6, further characterized in that the oil is contained within adhesives used to adhere the article directly to the body of a user.

10. A disposable absorbent article contained with wrapping material, wherein the wrapping material contains an amount of essential oil to provide a flavor and inhibit microbial growth.

11. The disposable absorbent article according to claim 10, further characterized in that the essential amount is from about 0.1 to about 8.0 weight percent.

12. A method for making a disposable absorbent article comprising the following steps: a) providing an absorbent material, b) providing a liquid-permeable material, c) providing a liquid impervious material, • d) enclosing the absorbent material with the material permeable to liquid and liquid impervious material; and e) contacting at least one of the absorbent material, liquid permeable material, liquid impermeable material, or a combination thereof with an effective amount of essential oil to provide a flavor and inhibit microbial growth. • The method according to claim 12, further characterized in that the method of contacting any of said materials with essential oil is selected from the group consisting of immersion, groove, spray, roller and swirl action. 14. The method according to claim 12, further characterized in that the amount of essential oil is from about 0.1 to about 8.0 weight percent. 15. The method according to claim 12, further comprising the step of attaching the absorbent material to the liquid permeable material, or the absorbent material to the liquid impervious layer with 20 adhesives. 16. The method according to claim 15, further characterized in that said essential oil is found in the adhesives, in an amount effective to provide a flavor and inhibit microbial growth. 17. The method according to claim 12, • characterized further because the absorbent material contains superabsorbents. 18. The method according to claim 17, further characterized in that said essential oil is found in the superabsorbents, in an amount effective to provide a flavor and inhibit microbial growth. •