MXPA01008661A - Layer materials treated with surfactant-modified hydrophobic odor control agents - Google Patents

Abstract

A treated layer material has at least one hydrophilic, odour-absorbing surface which is wettable to aqueous liquids and capable of controlling a wide variety of malodours. The layer material is treated with a hydrophilic surfactant-modified odour control agent prepared by mixing or chemically reacting a hydrophobic odour control agent with a surfactant or surfactant producing compound. Preferred hydrophobic compounds comprise aromatic compounds such as hexachlorophene, Calixarene derivatives or alkylmodified cyclophanes. The layer material thus treated can be used in a wide variety of personal care and medical absorbent products.

Description

TREATMENT MATERIALS TREATED WITH HYDROPHOBIC ODOR CONTROL AGENTS MODIFIED WITH SURFACTANT FIELD OF THE INVENTION This invention relates to compounds and chemical mixtures which prevent or control the odor and impart the surface wetting properties to the layer materials. In particular, it refers to layer materials treated with these compounds and dual-purpose chemical mixtures. i BACKGROUND OF THE INVENTION Non-woven fabrics, films, foams and other layer materials and their manufacture have been the subject of an extensive development that resulted in a wide variety of materials for numerous applications. For example, non-woven fabrics of light weight and open structure are used in personal care articles such as disposable diapers, such as lining fabrics that provide a dry skin contact but that easily transmit fluids to more absorbent materials. which may also be non-woven of a different composition and / or structure. Heavier-weight nonwovens can be designed with pore structures that make them suitable for filtration, absorbent and barrier applications such as wrappers for articles to be sterilized, wipes or protective garments for medical, veterinary or industrial. Even heavier weight non-woven materials have been developed for recreational, agricultural and construction uses. Films, foams, and other layer materials are also used in some of these applications, and may be combined with non-woven fabrics.

It is not always possible to efficiently produce a layer material having all the desired properties upon being formed, and it is often necessary to treat the material with a surfactant to improve or alter the surface properties such as wetting with one or more fluids, the repellency to one or more fluids, the electrostatic characteristics, the conductivity, and the softness to only name a few examples. Conventional surface treatments involve steps such as submerging the substrate in a treatment bath, coating or spraying the substrate with a treatment composition, and printing the substrate with the treatment composition. For cost and other reasons it is usually desirable to employ a minimum amount of treatment composition that will produce the desired effect with an acceptable degree of uniformity.

For many end-use applications of the thermoplastic layer material, it is desirable to reduce, avoid or eliminate odors. For diapers and other incontinence products, it is desirable to reduce or eliminate the ammonia odor which is formed from the urine. For women's hygiene products, it is desirable to reduce or eliminate the odor of triethylamine. Other common odor-producing substances include isovaleric acid, dimethyl disulfide and dimethyl trisulfide.

Odor control agents include odor inhibitors, odor absorbers, odor adsorbers, and other components which reduce, prevent or eliminate odors. Odor inhibitors prevent the odor from forming. For example, U.S. Patent No. 4,273,786 issued to Kraskin teaches the use of an aminopolycarboxylic acid compound to inhibit the formation of ammonia from urea in the urine. Absorbers and odor adsorbers remove the odor after it is formed. Examples of odor control agents that remove odor by absorption or adsorption include activated carbon, silica, and cyclodextrin.

Certain odor control agents are hydrophobic, and can not be easily applied from aqueous solutions to substrates because they do not dissolve or do not disperse in water. Even if these odor control agents could be applied from a solution, they would not easily moisten the substrate, or make its surface wettable, due to its hydrophobic nature. Examples of the hydrophobic odor control agents include, without limitation, those having aromatic chemistries.

Personal care products such as diapers and pads for women's care typically contain nonwoven polyolefin fabrics. Hydrophobic odor control agents can not usually be applied to the fabric surfaces of personal care products. These agents are usually introduced as powders or capsules to the product, resulting in several disadvantages. For example, placement and containment of powders or capsules in the product may be problematic. More importantly, powders and capsules do not have an optimum surface area for odor absorption due to a rather low surface to volume ratio. Therefore, more odor control agent will be required if it is in any of these forms.

There is a need or desire for mixtures and compounds to prevent odor and absorb odor which can be applied to a substrate (e.g., a thermoplastic substrate or other hydrophobic substrate) in a liquid or solvent form, and which have sufficient surface wetting properties to facilitate even fluid distribution and durability.

SUMMARY OF THE INVENTION The present invention is directed to a surfactant-modified odor control agent formed by either a) mixing a hydrophobic odor control people with a surfactant, or b) chemically reacting a hydrophobic odor control agent with a surfactant-producing compound. . Surfactant producing compounds include surfactants, and other compounds that transform hydrophobic odor control agents into surfactants after the chemical reaction. The invention is also directed to a layer material which has been treated with the odor control agent modified with surfactant. The surfactant modified odor control agent can be applied to the layer material using conventional external or internal application techniques, and is preferably applied using an external application technique. The resulting treated substrate is more wettable to aqueous liquids, and avoids, reduces and / or absorbs odors on its surfaces.

The substrate layer material may be a hydrophobic material, and may be a thermoplastic material made using one or more thermoplastic polymers. The layer material may be porous and permeable to water. For example, the layer material i may be a thermoplastic nonwoven filament fabric, a thermoplastic film, a foam layer or a combination thereof. A thermoplastic nonwoven filament fabric is preferred. The treated layer material can be used in a wide variety of products for personal care and medical products, and in other applications.

Surfactant-modified odor control agents can be applied to hydrophobic substrates or other substrates (eg, polyolefin-based films, foam layers and non-woven fabrics) of an aqueous solution, because the surface of the solution is low enough to wet the substrate with low surface energy. For example, the coating of the surfactant-modified odor control agent on the polyolefin fibers of a polyolefin non-woven fabric will optimize the surface-to-volume ratio of the odor control chemistry, and thus provide better odor control. (for example, odor absorption, adsorption, prevention or inhibition). In addition, fibers coated with a surfactant-modified odor control agent will be in direct contact with body fluids as fluids enter and transmitted through the fabric components of the personal care product. This will provide optimal odor control since odors are believed to emanate from body fluids.

It is therefore a feature and an advantage of the invention to provide a surfactant modified odor control agent having the odor control properties of a hydrophobic odor control agent, which can be applied to a substrate using techniques from solution.

It is also a feature and an advantage of the invention to provide a treated layer material having at least one surface which is more wettable to aqueous liquids than the untreated layer material, and which inhibits and / or absorbs common smells.

It is also a feature and an advantage of the invention to provide a personal care product or fabric which uses the treated layer material which is more humidifying and inhibits and / or absorbs odors on at least one outer surface.

It is also a feature and an advantage of the invention to provide a fabric or medical product which uses the treated layer material that is more wettable, and inhibits and / or absorbs odors in at least one outer surface.

DEFINITIONS The term "layer material" refers to a material that exists in the form of a paper type or flexible fabric type material, including without limitation fabrics and non-woven filament fabrics, thermoplastic films, foam materials flexible thermoplastics, and combinations of multiple layers including one or more of these.

The term "porous water permeable layer material" refers to a material present in one or more layers, such as a film, a nonwoven fabric, or an open cell foam, which is porous and which is permeable to water due to the flow of water and other aqueous liquids through the pores. The pores in the film or in the foam, or in the spaces between the fibers or filaments in a nonwoven fabric are sufficiently large and sufficiently frequent allow the runoff and flow of liquid water through the material.

The term "nonwoven fabric or fabric" means a fabric having a structure of individual fibers or threads which are interleaved, but not in a regular or identifiable manner as in a woven fabric. Fabrics or non-woven fabrics have been formed from many processes such as, for example, meltblowing processes, spinning bonding processes, air laying processes, and carded and bonded tissue processes. The basis weight of non-woven fabrics is usually expressed in ounces of material per square yard (osy) or grams per square meter (gsm) and useful fiber diameters are usually expressed in microns. (Note that to convert from ounces per square yard to grams per square meter, you must multiply ounces per square yard by 33.91).

The term "microfiber" means small diameter fibers having an average diameter of no more than about 75 microns, for example, having an average diameter of from about 1 micron to about 50 microns, or more particularly, microfibers can have an average diameter of from about 1 miera to about 30 micras. Another frequently used expression of fiber diameter is denier which is defined as grams per 9,000 meters of a fiber. For a fiber that has a circular cross section, the denier can be calculated as a diameter of fiber i in square microns, multiplied by the density in grams / cubic centimeter, multiplied by 0.00707. A lower denier indicates a finer fiber and a higher denier indicates a thicker or heavier fiber. For example, the diameter of a polypropylene fiber given as 15 microns can be converted to denier by placing the square, multiplying the result by .89 grams / cubic centimeter and multiplying by .00707. Therefore, a polypropylene fiber of 15 microns has a denier of about 1.42 (152 x 0.89 x .00707 = 1.415).

Outside the United States of America, the unit of measurement is most commonly "tex", which is defined as grams per kilometer of fiber. The tex can be calculated as denier / 9.

The term "spunbonded fibers" refers to fibers of small diameter which are formed by extruding the melted thermoplastic material as filaments from a plurality of fine capillary vessels of a spinner having a circular configuration or other configuration., with the diameter of the extruded filaments then being rapidly reduced, such as, for example, is indicated in United States of America No. 4,340,563 issued to Appel et al., and in the United States of America patent. No. 3,692,618 issued to Dorschner et al., In US Pat. No. 3,802,817 issued to Matsuki et al., In the patents of the United States of America nos. 3,338,992 and 3,341,394 granted to Kinney, in the United States of America patent No. 3,502,763 granted to Hartmann, in the United States of America patent No. 3,502,538 granted to Petersen, and in the patent of the United States of America No 3,542,615 issued to Dobo and others, each of which is hereby incorporated by reference in its entirety. . Spunbonded fibers are cooled and are generally non-tacky when they are deposited on a collecting surface. Spunbonded fibers are generally continuous and frequently have average diameters greater than about 7 microns, more particularly between about 10 and 30 microns.

The term "meltblown fibers" means fibers formed by extruding a melted thermoplastic material through a plurality of thin, usually circular, capillaries, like melted threads or filaments into gas streams (eg, air). ) heated at high speed which attenuate the filaments of the molten thermoplastic material to reduce its diameter which can be reduced to a microfiber diameter. Then, the meltblown fibers are carried by the high velocity gas stream and are deposited on a collecting surface to form a randomly dispersed meltblown fabric. Such a process is described, for example, in United States of America Patent No. 3,849,241 issued to Butin et al. The melt blown fibers are microfibers which can be continuous or discontinuous, are generally smaller than 10 microns in diameter, and are generally self-supporting when deposited on a collecting surface. The meltblown fibers used in the present invention are preferably and essentially continuous in length.

The term "monocomponent fibers" refers to a fiber formed from one or more extruders using only one polymer. This does not mean that fibers formed from a polymer to which small amounts of additives have been added for color, antistatic properties, lubrication, hydrophilicity, repellency, etc. are excluded. These additives, for example, titanium dioxide for color, are generally present in an amount of less than 5 percent by weight, and more typically of about 2 percent by weight or less.

The term "coform material" refers to a product containing about 10% by weight to 90% by weight of the thermoplastic meltblown fibers and about 10% by weight to 90% by weight of short length pulp fibers Assorted within the melted blown fiber matrix. Most commonly, coform materials contain about 20% by weight to 70% by weight of thermoplastic meltblown fibers of about 30% by weight to 80% by weight of pulp fibers.

The term "film" refers to a thermoplastic film made using a film extrusion process, such as an extrusion process of blown film or set film. The term "porous water-permeable films" refers to films made porous by perforation or perforation ", and to films that are made porous by mixing the polymer with a filler, forming a film of the mixture, and stretching the film.

The term "foam material" refers to a thermoplastic layer material made with the aid of a foaming process. The term "open cell foam material" refers to a foam layer whose cells interconnect, or otherwise create pores from one surface of the layer to the opposite surface. i The term "polymer" includes, but is not limited to, homopolymers, to copolymers, such as, for example, block, graft, random, and alternating copolymers, to terpolymers, etc., and to mixtures and modifications from the same. In addition, unless specifically limited otherwise, the term "polymer" will include all possible geometric configurations of the material. These configurations include but are not limited to isotactic, syndiotactic and atactic symmetries.

The term "bicomponent filaments or fibers" refers to fibers which have been formed from at least two extruded polymers of separate extruders but spun together to form a fiber. The polymers are arranged in different areas placed essentially constant across the cross section of the bicomponent fibers and which extend continuously along the length of the bicomponent fibers. The configuration of such bicomponent fiber can be, for example, a pod / core arrangement where one polymer is surrounded by another or can be a side-by-side arrangement or an arrangement of "islands in the sea". The bicomponent fibers are shown in U.S. Patent No. 5,108,820 issued to Kaneko et al., In U.S. Patent No. 5,336,552 issued to Strack et al. And in the United States Patent of America No. 5,382,400 issued to Pike and others, each of which is hereby incorporated by reference in its entirety. For the two component fibers, the polymers may be present in proportions of 75/25, 50/50, 25/75 or any other desired proportions. Conventional additives, such as pigments and surfactants, can be incorporated into one or both polymer streams, or applied to the filament surfaces.The term "pulp fibers" refers to fibers from natural sources such as from woody and non-woody plants. Woody plants include, for example, deciduous and coniferous trees. Non-woody plants include, for example, cotton, flax, esparto grass, benzene, straw, hemp and bagasse.

The term "average pulp fiber length" refers to the average heavy length of the pulp determined i using a Kajaani fiber analyzer model No. FS-100 available from Kajaani Oy Electronics in Kajaani, Finland. Under this test procedure, a sample of fiber is treated with a macerator liquid to ensure that pieces or bunches of fiber are present. Each fiber sample is dispersed in hot water and diluted to around 0.001% concentration. The individual test samples are drawn in portions of approximately 50 milliliters to 500 milliliters from the diluted solution and are tested using the normal Kajaani fiber analysis procedure. The average heavy fiber lengths can be expressed by the following equation: k S (X ± * nX / n Xi> 0 where k = maximum fiber length, Xi = individual fiber length, = number of fibers that have the length X ± and n total number of fibers measured.

The term "superabsorbent material" refers to an organic or inorganic material insoluble in water and swellable in water capable, under the most favorable conditions, of absorbing at least about 20 times its weight, preferably at least about 30 times its weight in an aqueous solution containing 0.9% by weight of sodium chloride.

The term "air binding" or " " means a process for joining a nonwoven, for example, a two-component fiber fabric in which the air that is sufficiently hot to melt one of the polymers of which The fibers of the tissue are made through the tissue. The air speed is often between 100 feet per minute and 500 feet per minute and the dwell time can be as long as 6 seconds. The melting and resolidification of the polymer provides the bond. The binding through air has a restricted variability and is generally seen as a process of joining a second step. Since air-binding requires the melting of at least one component to achieve the bond, it is restricted to two-component fabrics such as bicomponent fiber fabrics or fabrics containing a sticky fiber powder.

The term "thermal point union" involves passing a fabric or fabric of fibers that are to be joined through a heated calender roll and an anvil roller.

The calendering roller usually has, although not always, a pattern in some way so that the entire fabric is not bonded through its entire surface. As a result of this, various patterns for calendering rolls have been developed for functional as well as aesthetic reasons. An example of a pattern has points and is the Hansen Pennings pattern or "H &P" with a bound area of around 30% with around 200 unions / square inch as taught in U.S. Patent No. 3,855,046 issued to Hansen and Pennings. The H &P pattern has bolt or square point joining areas where each bolt has a dimension of 0.038 inches (0.965 millimeters), a 0.070 inch clearance (1,778 mm) between the bolts, and a joint depth of 0.023 inches (0.584 mm). The resulting pattern has a bound area of about 29.5%. Another typical point union pattern is the expanded Hansen and Pennings junction pattern or "EHP" which produces a 15% joint area with a square bolt that has a side dimension of 0.037 inches (0.94 millimeters), a bolt spacing of 0.097 inches (2.464 millimeters) and a depth of 0.039 inches (0.991 millimeters). Another typical point union pattern designated "714" has square bolt joint areas where each bolt has a side dimension of 0.023 inches, a spacing of 0.062 inches (1,575 millimeters) between the bolts, and a joint depth of 0.033 inches (0.838 millimeters). The resulting pattern has a 'bound area of about 15%. Yet another common pattern is the star pattern in C which has the united area of about 16.9%. The star pattern in C has a bar in the transverse direction or "corduroy" design interrupted by shooting stars. Other common patterns include a diamond pattern with repetitive and slightly off-center diamonds and a woven wire pattern that looks like its name suggests, for example, as a window grid. Typically, the percent bond area varies from about 10% to about 30% of the area of the fabric laminated fabric. As is well known in the art, point bonding keeps laminated layers together as well as imparting integrity to each individual layer by joining the filaments and / or fibers within each layer.

The term "personal care product" includes, without limitation, diapers, underpants, swimwear, absorbent underpants, baby wipes, adult incontinence products, and women's hygiene products.

»The term" medical product "includes, without limitation, garments, underpants, bandages, absorbent covers and medical wipes.

The term "hydrophilic" or "wettable" means that the polymeric material has an apparent surface free energy so that the polymeric material is wettable by an aqueous medium, for example, a liquid medium of which water is a major component. That is, an aqueous medium moistens the non-woven fabric. "Apparent surface free energy" refers to the highest surface tension of an aqueous liquid which moistens the polymeric material. For example, the apparent surface free energy of a polymeric material that is wetted by an aqueous liquid having a surface tension of 72 dynes / centimeter is at least 72 dynes / centimeter and possibly higher. In the fabrics of the invention, a surface of the non-woven fabric has been treated with a surfactant-modified odor control agent using the internal or external application techniques described below.

The term "-surfactant" refers to a compound or mixture which, when applied to a surface of a substrate, causes the surface to become more wettable as defined above. In one case, the substrate is not wettable independently and the surfactant becomes wettable. In another case, the substrate is somewhat humid and the surfactant makes it more humid or moistened more easily.

The term "surfactant-producing moiety" or "Surfactant producing compound" refers to a chemical compound or group which, when reacted or mixed with another compound (e.g., an odor control agent) causes the reacted compound or mixture to behave as a surfactant. The compound - or the surfactant-producing moiety may or may not behave as a surfactant prior to reaction or chemical mixing.

The term "odor control agent" includes compounds and mixtures which inhibit the formation of at least one undesirable odor, as well as compounds and mixtures which absorb an undesirable odor that has already formed.

The term "surfactant modified odor control agent" refers to a mixture, and / or a reaction product, between an odor control agent and a surfactant or surfactant-producing moiety, which both act as a surfactant and an odor control agent.

DETAILED DESCRIPTION OF THE INCORPORATIONS CURRENTLY PREFERRED The present invention is directed to a modified odor control agent. with surfactant, a layer material treated with a surfactant modified odor control agent, and an absorbent product which uses the treated layer material. The surfactant modified odor control agent is prepared by a) mixing a hydrophobic odor control agent with a surfactant, and / or b) chemically reacting a hydrophobic odor control agent with a surfactant producing compound. The term "surfactant producing compound" includes surfactants, and other hydrophilic compounds which transform hydrophobic odor control agents into surfactants after the chemical reaction. Mixing and / or chemical reaction can be achieved using techniques familiar to persons skilled in the art.

The hydrophobic odor control agents include any odor control agent which is antagonistic to water, and is unable to dissolve in water. Suitable hydrophobic odor control agents include aromatic odor control agents. Examples include phenolic derivatives which have antimicrobial effects which inhibit the growth of odor-producing bacteria. The cresols, and diphenyl compounds such as hexachlorophene, are among this group of odor inhibitors. Other aromatic odor control agents include without limitation the alkyl-modified aromatic compounds, for example, the alkyl-modified cyclo-phanes and derivatives thereof. Preferred alkyl groups attached to the aromatic ring have from about 3 to about 18 carbon atoms. Other hydrophobic odor control agents include hydrophobic compounds which reduce, inhibit, prevent or otherwise control undesirable odors from common sources such as ammonia, triethylamine, isovaleric acid, dimethyl disulfide, dimethyl trisulfide, indole, skatole , and similar.

Hydrophilic surfactants and surfactant-producing compounds include surfactants of other compounds with functional groups that have an affinity for water, that are wettable by water, and / or that have a tendency to make other materials and compounds wettable with water . Examples of surfactants or surfactant producing compounds which can be either mixed or chemically bound to a hydrophobic odor control agent include, but are not limited to polyethylene glycols, polypropylene glycol-polyethylene glycol block copolymers, polyolefinglicol methyl ethers (for example, polyethylene glycol methyl ethers), polyvinyl alcohols, polyacrylic acids, polyvinyl pyrrolidones, and derivatives and combinations thereof. Other compounds that have hydroxyl, carboxyl, amino groups? or amido can also be useful. Preferred hydrophilic surfactants are polyolefin glycols and polyolefinglicol methyl ethers having a weight average molecular weight of about 600-20,000, more preferably about 1,000-9,000.

The hydrophobic odor control agents and the hydrophilic surfactant producing compounds can be mixed or chemically reacted using techniques familiar to those skilled in the art of organic chemistry. For example, an alkylated phenol can be attached to a polyethylene glycol, polyacrylic acid or other carboxyl compound to give a surfactant modified odor control agent having the following general formula: Wherein one of R 'and R "is a polyethylene glycol, a polyacrylic acid or another hydrophilic functional compound for example sulfonic, hydroxyl, carboxyl, amino or amido), the other of R 'and R "is an alkyl group having from 3 to 18 carbon atoms, and n is an integer from 3 to 8.

Surfactant modified odor control agents having this general formula can be collectively referred to as Calix (n) arenos.

The starting layer material is treated with the modified odor control agent with surfactant. The surfactant modified odor control agent is applied to the layer material using conventional techniques to apply surfactants internally p externally. Preferably, the surfactant modified odor control agent is applied externally in the form of a liquid, using techniques such as embedding, spraying, brushing or other liquid coating techniques. The odor control agent modified with surfactant can be mixed with water or another solvent to facilitate its application.

Examples of suitable layer materials include, but are not limited to, thermoplastic layer materials, for example, thermoplastic nonwoven filament fabrics, thermoplastic films, and thermoplastic foam layers. The layer material can be a porous and water permeable layer material. Examples of water permeable layer materials include thermoplastic nonwoven filament fabrics, open cell foam layers, and films which are perforated or otherwise porous, such as by stretching a film made of a mixture of a thermoplastic material and a particulate filler. i The preferred layer material used in the invention is a nonwoven fabric that includes a plurality of filaments made from one or more polymers. The non-woven fabric may be a spunbonded fabric, a meltblown fabric, a bonded and bonded fabric or other type of non-woven fabric, and may be present in a single layer or in a multilayer composite including one or more layers of non-woven fabric, and in some cases, one or more layers of film or foam. The fabric may include monocomponent or bicomponent filaments, or a combination including one or both types of filaments. The non-woven fabric can have a variety of basis weights, preferably varying from about 0.1 grams per square meter to 200 grams per square meter (gsm). A preferred nonwoven fabric is a coform material which includes a matrix of blown fibers with polyolefin melting and a large percentage (frequently 30% by weight 80% by weight) of pulp fibers dispersed in the matrix of the blown fibers with fusion. Another preferred non-woven fabric is an air-laid fabric of polyolefin fibers and pulp fibers. A wide variety of thermoplastic polymers can be used to build the starting layer material, including without limitation polyamides, polyesters, polyolefins, ethylene and propylene copolymers, copolymers of ethylene or propylene with an alpha-olefin C4-C20, terpolymers of ethylene with propylene and a C4-C20 alpha-olefin, copolymers of ethylene vinyl acetate, copolymers of propylene vinyl acetate, elastomers of styrene-poly (ethylene-alpha-olefin), polyurethanes, AB block copolymers in where A is formed of poly (vinyl arene) moieties such as polystyrene and B is a. middle elastomeric block such as a conjugated diene or lower alkene, polyethers, polyether esters, polyacrylates, ethylene alkyl acrylates, polyisobutylene, poly-1-butene, poly-1-butene copolymers including ethylene-1-butene copolymers, polybutadiene, copolymers of isobutylene-isoprene, and combinations of any of the foregoing. Polyolefins are preferred. More preferred are polyethylene and polypropylene homopolymers and copolymers.

The surfactant modified odor control agent can be applied using internal or external application techniques known in the art. Some compounds and mixtures operate more favorably when applied internally and are called "internal additives". Others operate more favorably when applied externally and are called "external additives". Still other compounds and mixtures operate properly as both internal and external additives.

As is generally known, an internal additive is typically mixed with the polymer used to make a nonwoven fabric, film, foam, or other layer material, and migrates to the surfaces of the non-woven fabric filaments or other layer material during and / or after their training. Frequently, the migration results from a stimulus, such as the heat applied to the layer material. An external additive is applied externally to the surfaces of the layer material after it is formed. An external additive can be applied by soaking, soaking, spraying or otherwise coating the layer material with a solvent or other medium containing the additive.

The external application methods are currently preferred for the surfactant modified odor control agents used with the treated materials of the invention.

The surfactant modified odor control agent (either formed by mixing or chemical reaction) can be mixed with water or other suitable solvent in a concentration of about 0.1% by weight to 30% by weight of the agent, preferably around from 0.5% by weight to 15% by weight of the agent, more preferably from about 1% by weight to 5% by weight of the agent. The solution can then be applied to the layer or fabric material by dipping, spraying, and brush coating, printing or other suitable technique. The treated layer material can then be dried using heat, forced air convection, vacuum induced evaporation, or other conventional drying technique.

The treated layer materials thus formed have wettability to aqueous liquids, and odor resistance to a wide variety of odor producing halves. The terms "odor resistance" and "odor control" refer to the ability of the treated layer materials to react, inhibit, neutralize, form complexes, or otherwise prevent odor-producing compounds from forming or reducing odors produced by these. Examples of the odor-producing compounds which the fabrics of this invention can inhibit, reduce or eliminate, include without limitation ammonia, triethylamine, isovaleric acid, dimethyl disulphide, dimethyl trisulfide, indole, skatole and the like.

The amount of surfactant modified odor control agent necessary to provide sufficient odor and odor absorption may vary depending on the half of the surfactant and the odor control agent mixed or reacted together, the type of base polymer, and of whether the odor control agent modified with surfactant is added internally or externally. On a solvent-free weight basis, the surfactant-modified odor control agent should generally be about 0.05% by weight to 10% by weight of the layer material to which it is applied, preferably about 0.1% by weight at 5% by weight, more preferably from about 1% by weight to 3% by weight.

The treated layer materials thus formed can be used in a wide variety of absorbent product applications including, in particular, absorbent personal care products. Absorbent personal care products include diapers, underpants, swimwear, absorbent briefs, baby wipes, adult incontinence products, women's hygiene products, and the like . In the absorbent products, the treated layer material (if it is permeable to water) can be used as a cover sheet or a containment matrix for an absorbent medium capable of absorbing aqueous liquids). An absorbent medium may include, for example, pulp fibers alone or in combination with a superabsorbent material. The treated layer material can also be used in medical absorbent products, including without limitation, garments, inner pads, absorbent covers, bandages, and medical cleansing wipes.

The pulp fibers may be any of a pulp of fiber length. high average, a pulp of low average fiber length, or a mixture thereof. Preferred pulp fibers include cellulose fibers. The term "high average fiber length pulp" refers to pulp that contains a relatively small amount of short fibers and non-fiber particles. The high fiber length pulps typically have an average fiber length greater than about 1.5 millimeters, preferably about 1.5 millimeters to 6 millimeters, as determined by means of a fiber optic analyzer, such as a Kajaani tester mentioned above . The sources generally include non-secondary (virgin) fibers, as well as secondary fiber pulp which has been screened. Examples of high average fiber length pulps include virgin softwood pulp bleached and unbleached.

The term "low average fiber length pulp" refers to pulp that contains a significant amount of short fibers and non-fiber particles. The low average fiber length pulps have an average fiber length of less than about 1.5 millimeters, preferably from about 0.7 millimeters to 1.2 millimeters, as determined by a fiber optic analyzer such as the Kajaani tester mentioned above. Examples of low fiber length pulps include virgin hardwood pulp, as well as secondary fiber pulp from sources such as office waste, newspaper, and cardboard cutouts.

Examples of high average fiber length wood pulps include those available from U.S. Alliance Coosa Pines Corporation, sold under the trade designations Longlac 19, Coosa River 56, and Coosa River 57. Low average fiber length pulps may include some virgin hardwood pulp and secondary fiber pulp (eg, recycled) ) from 'sources that include newspaper, reclaimed cardboard, and office waste. High average fiber length blends and low average fiber length pulps may contain a predominance of low average fiber length pulps. For example, the blends can contain more than about 50% by weight of the pulp of low average fiber length and less than about 50% by weight pupa of average fiber length of high weight.

The term "superabsorbent" or "superabsorbent material" refers to an inorganic or organic material insoluble in water, and swellable in water capable, under the most favorable conditions, of absorbing at least about 20 times its weight and, more desirably, of at least about 30 times its weight in an aqueous solution containing 0.9 percent by weight of sodium chloride.

The superabsorbent materials can be natural, synthetic and natural modified materials and polymers. In addition, the superabsorbent materials may be inorganic materials such as silica gels, or organic compounds such as crosslinked polymers. The term "cross-linked" refers to any means for effectively making the materials normally water-soluble essentially insoluble, but swellable in water. Such media may include, for example, physical entanglement, crystalline domains, covalent bonds, complexes and ionic associations, hydrophilic associations, such as hydrogen bonding, and hydrophobic associations or Van der aals forces.

Examples of polymers of synthetic superabsorbent material include the ammonium and alkali metal salts of poly (acrylic acid) and poly (methacrylic acid), poly (acrylamide), poly (vinyl ethers), anhydride copolymers maleic with vinyl ethers and alpha olefins, poly (vinyl pyrrolidone), poly (vinyl morpholinone), poly (vinyl alcohol) and mixtures and copolymers thereof. Additional materials and superabsorbents include the natural and modified natural polymers such as hydrolyzed acrylonitrile grafted starch, acrylic acid grafted starch, methylcellulose, chitosan, carboxymethylcellulose, hydroxypropylcellulose, and natural gums such as alginates, xanthan gum, locust bean gum and the like. Mixtures of natural and fully or partially synthetic superabsorbent polymers may also be useful in the present invention. Other suitable absorbent gelation materials are described by Assarsson et al. In U.S. Patent No. 3,901,236 issued August 26, 1975. Processes for preparing synthetic absorbent gelation polymers are described in the US Pat. United States of America No. 4,076,663 granted on February 28, 1978 to Masuda and others, and United States of America No. 4,286,082 granted on August 25, 1981 to Tsubakimoto et al.

The superabsorbent materials can be xerogels which form hydrogels when wetted. The term "hydrogel", however, has been commonly used to also refer to both the wet and unmoistened forms of the superabsorbent polymer material. The superabsorbent materials can be in many forms such as flakes, powders, particles, fibers, continuous fibers, nets, fabrics and spun filaments of solution. The particles can be of any desired shape, for example, spiral or semi-spiral, cubic, rod-type, polyhydric, etc. Needles, flakes and fibers and combinations can also be used.

The superabsorbents are generally available in particle sizes ranging from about 20 to about 1.00,000 microns. Examples of commercially available particulate superabsorbents include SANWET® IM-3900 and SANWET® IM-5000P, available from Hoescht Celanese located in Portsmouth, Virginia, DRYTECH® 2035LD available from Dow Chemical Company, located in Midland, Michigan, and FAVOR® SXM880, available from Stockhausen, located in Greensboro, North Carolina. As an example of a fibrous superabsorbent is OASIS® 101, available from Technical Absorbents, located in Grimsby, England.

As indicated above, the treated layer material may be a cover sheet or a matrix for an absorbent medium. The non-woven filaments can be used as a matrix, and can be combined with the pulp fibers and (optionally) a superabsorbent material using a process well known in the art. For example, a coform process may be employed, in which at least one meltblowing die head is arranged near a conduit through which other materials are aggregated while the woven is being formed. The coform processes are described in U.S. Patent No. 4,818,464 to Lau and 4,100,324 to Anderson et al., Whose descriptions are incorporated by reference. Thermoplastic non-woven filaments and pulp fibers can also be combined using hydraulic entanglement or mechanical entanglement. A hydraulic entangling process is described in U.S. Patent No. 3,485,706 issued to Evans, the disclosure of which is incorporated herein by reference.

When the treated thermoplastic nonwoven filaments are used as a matrix for an absorbent nonwoven fabric composite, the composite should contain about 5% by weight to 97% by weight pulp fibers, preferably about 35% by weight a 95% by weight of pulp fibers, more preferably from about 50% by weight to about 95% by weight of the pulp fibers. When a superabsorbent material is present, it should constitute about 5% by weight to 90% by weight of the compound, preferably from about 10% by weight to 60% by weight, more preferably from about 20% by weight to 50% by weight. In either case, the thermoplastic nonwoven matrix should constitute about 3% by weight to about 95% by weight of the composite, preferably about 5% by weight to 65% by weight, more preferably about 5% by weight. 50% weight by weight.

After combining the ingredients together, the absorbent nonwoven composites can be joined together using the thermal bond or air bonding techniques described above, to provide a coherent high integrity structure. Although the embodiments of the invention described herein are currently preferred, various modifications and improvements can be made without departing from the spirit and scope of the invention. The scope of the invention is indicated by the appended claims, and all changes that fall within the meaning and range of equivalents are intended to be encompassed therein.

Claims (55)

R E I V I N D I C A C I O N S

1. A surfactant modified odor control agent comprising a material selected from the group consisting of a) a mixture of a surfactant with a hydrophobic odor control agent, b) a reaction product of a surfactant producing compound with a hydrophobic odor control agent, and c) combinations of the above.

2. The surfactant modified odor control agent as claimed in clause 1, characterized in that the hydrophobic odor control agent comprises an aromatic odor control agent.

3. The odor control agent modified with surfactant as claimed in clause 2, characterized in that the aromatic odor control agent comprises a phenolic compound.

4. The odor control agent modified with surfactant as claimed in clause 3, characterized in that the phenolic compound comprises a cresol compound.

5. The odor control agent modified with surfactant as claimed in clause 3, characterized in that the phenolic compound comprises a diphenyl compound.

6. The surfactant modified odor control agent as claimed in clause 2, characterized in that the aromatic odor control agent comprises an alkyl-modified aromatic compound.

7. The surfactant modified odor control agent as claimed in clause 6, characterized in that the alkyl-modified aromatic compound comprises an alkyl-modified cyclophane or a derivative thereof.

8. The surfactant modified odor control agent as claimed in clause 6, characterized in that the alkyl-modified aromatic compound comprises an alkyl group having about 3 carbon atoms to 18 carbon atoms.

9. The surfactant-modified odor control agent as claimed in clause 1, characterized in that the surfactant or the surfactant-producing compound comprises a polyolefin glycol compound.

10. The odor control agent modified with surfactant as claimed in clause 9, characterized in that the polyolefinglicol compound comprises polyethylene glycol.

11. The surfactant modified odor control agent as claimed in clause 9, characterized in that the polyolefinglycol compound comprises polypropylene glycol.

12. The surfactant modified odor control agent as claimed in clause 9, characterized in that the polyolefinglicol compound comprises a mixture of polyethylene glycol and polypropylene glycol.

13. The surfactant-modified odor control agent as claimed in clause 9, characterized in that the polyolefinglycol compound comprises polyolefinglycol methyl ether.

14. The surfactant-modified odor control agent as claimed in clause 1, characterized in that the surfactant or the surfactant-producing compound comprises a carboxyl compound.

15. The surfactant modified odor control agent as claimed in clause 14, characterized in that the carboxyl compound comprises a polyacrylic acid.

16. The surfactant-modified odor control agent as claimed in clause 1, characterized in that the surfactant or the surfactant-producing compound comprises a vinyl alcohol polymer.

17. The surfactant-modified odor control agent as claimed in clause 1, characterized in that the surfactant or the surfactant-producing compound comprises a polyvinyl pyrrolidone. '

18. The surfactant modified odor control agent as claimed in clause 1, characterized in that the material comprises a compound having the following general formula: Where one of R 'and R "is selected from polyethylene glycols, polyacrylic acids, and other hydroxyl functional, carboxyl functional, sulphonic, aminic and amidoic compounds, the other of R' and R" is selected from the alkyl groups which they have from 3 carbon atoms to 18 carbon atoms, and n is an integer from 3 to

19. A treated layer material comprising a substrate layer treated with a surfactant-modified odor control agent selected from the group consisting of a) a mixture of a surfactant with a hydrophobic odor control agent, b) a product, reaction of a surfactant producing compound with a hydrophobic odor control agent, and c) combinations of the foregoing.

20. The treated layer material as claimed in clause 19, characterized in that the substrate layer comprises a non-woven thermoplastic filament fabric.

21. The treated layer material as claimed in clause -19, characterized in that the substrate layer comprises a thermoplastic film.

22. The treated layer material as claimed in clause 19, characterized in that the substrate layer comprises a thermoplastic foam layer.

23. The treated layer material as claimed in clause 19, characterized in that the substrate layer comprises a water permeable layer.

24. The treated layer material as claimed in clause 19, characterized in that the hydrophobic odor control agent comprises an aromatic odor control agent.

25. The treated layer material as claimed in clause 24, characterized in that the aromatic control agent comprises a phenolic compound.

26. The treated layer material as claimed in clause 24, characterized in that the aromatic odor control agent comprises an alkyl-modified aromatic compound.

27. The treated layer material as claimed in clause 26, characterized in that the alkyl-modified aromatic compound comprises an alkyl-modified cyclophane or derivative thereof.

28. The treated layer material as claimed in clause 26, characterized in that the alkyl-modified aromatic compound comprises an alkyl group having about 3 carbon atoms to 18 carbon atoms.

29. The treated layer material as claimed in clause 19, characterized in that the surfactant or the surfactant producing compound comprises a polyolefin glycol compound.

30. The treated layer material as claimed in clause E9, characterized in that the polyolefinglicol compound comprises polyethylene glycol.

31. The treated layer material as claimed in clause 29, characterized in that the polyolefinglicol compound comprises polypropylene glycol.

32. The treated layer material as claimed in clause 29, characterized in that the polyolefinglicol compound comprises a combination of polyethylene glycol and polypropylene glycol.

33. The treated layer material as claimed in clause 29, characterized in that the polyolefinglicol compound comprises a polyolefinglicol methyl ether.

34. The treated layer material as claimed in clause 19, characterized in that the surfactant or the surfactant producing compound comprises a carboxyl compound.

35. The treated layer material as claimed in clause 19, characterized in that the surfactant modified odor control agent comprises a compound having the following general formula: Wherein one of R 'and R "is selected from polyethylene glycols, polyacrylic acids, and other hydroxyl functional, carboxyl functional, sulphonic, aminic and amido compounds. the other of R 'and R "is selected from the alkyl groups having from 3 carbon atoms to 18 carbon atoms, and i n is an integer from 3 to 8.

36. The treated layer material as claimed in clause 19, characterized in that it comprises about 0.05% by weight to 10% by weight of a surfactant modified odor control agent.

37. The treated layer material as claimed in clause 19, characterized in that it comprises about 0.1% by weight to 5% by weight of a surfactant modified odor control agent. i

38. The treated layer material as claimed in clause 19, characterized in that it comprises about 1% by weight to 3% by weight of a surfactant modified odor control agent.

39. The treated layer material as claimed in clause 19, characterized in that the substrate layer comprises a polymer selected from the group consisting of polyamides, polyolefins, polyesters, ethylene and propylene copolymers, ethylene or propylene copolymers with a C4-C20 alpha-olefin, terpolymers of ethylene with propylene and a C4-C20 alpha-olefin, copolymers of ethylene vinyl acetate, copolymers of propylene vinyl acetate, elastomers of styrene-poly (ethylene-alpha-olefin, polyurethanes, copolymers of block AB, wherein A is formed of poly (vinyl arene) moieties, such as polystyrene and B is an elastomeric middle block such as a conjugated diene or a lower alkene, polyethers, polyether esters, polyacrylates, ethylene alkyl acrylates, polyisobutylene, polybutadiene, isobutylene-isoprene copolymers and combinations of any of the foregoing.

40. The treated layer material as claimed in clause 19, characterized in that the substrate layer comprises a polyolefin.

41. The treated layer material as claimed in clause 19, characterized in that the substrate layer comprises a polyethylene copolymer or homopolymer.

42. The treated layer material as claimed in clause 19, characterized in that the < The substrate comprises a polypropylene copolymer or homopolymer.

43. An absorbent product comprising: an absorbent medium capable of absorbing liquids; Y a layer material having a treated surface capable of inhibiting or reducing at least one selected odor of ammonia, triethylamine, isovaleric acid, dimethyldisulfide, dimet-ultrisulfide, indole, skatole, and combinations thereof; wherein the treated surface comprises a hydrophobic odor controlling agent modified with hydrophilic surfactant.

44. The absorbent product as claimed in clause 43, characterized in that it comprises a diaper.

45. The absorbent product as claimed in clause 43, characterized in that it comprises training underpants.

46. The absorbent product as claimed in clause 43, characterized in that it comprises swimming clothing.

47. The absorbent product as claimed in clause 43, characterized in that it comprises absorbent undergarments.

48. The absorbent product as claimed in clause 43, characterized in that it comprises a baby wiping cloth.

49. The absorbent product as claimed in clause 43, characterized in that it comprises a product for adult incontinence.

50. The absorbent product as claimed in clause 43, characterized in that it comprises a product for the hygiene of women.

51. The absorbent product as claimed in clause 43, characterized in that it comprises a medical garment.

52. The absorbent product as claimed in clause 43, characterized in that it comprises an inner pad.

53. The absorbent product as claimed in clause 43, characterized in that it comprises an absorbent cover. • 5

54. The absorbent product as claimed in clause 43, characterized in that it comprises a bandage.

55. The absorbent product as 10 claimed in clause 43, characterized in that it comprises a medical cleaning cloth. SUMMARY A treated-bed material has at least one hydrophilic odor absorbing surface which is wettable with aqueous liquids and is capable of controlling a wide variety of bad odors. The layer material is treated with a modified odor control agent with hydrophilic surfactant prepared by mixing or chemically reacting a hydrophobic odor control agent with a surfactant or a surfactant producing compound. The layer material thus treated can be used in a wide variety of medical absorbent and personal care products, as well as in other applications.