KR100335554B1 - Antimicrobial-coated hydrogel forming absorbent polymers - Google Patents

Abstract

The present invention relates to an antimicrobial hydrogel forming absorbent polymer comprising a hydrogel forming absorbent polymer and an antimicrobial agent, wherein the hydrogel forming absorbent polymer is coated with an antimicrobial agent. The invention also relates to a process for preparing such antimicrobial hydrogel forming absorbent polymers. The invention also relates to a disposable absorbent article comprising an antibacterial hydrogel forming absorbent polymer.

Description

Antimicrobial coated hydrogel-forming absorbent polymer {ANTIMICROBIAL-COATED HYDROGEL FORMING ABSORBENT POLYMERS}

Various disposable absorbent products are known in the literature that are not only efficient for the absorption of body fluids such as urine, blood, menstrual blood and the like, but are also designed to be hygienic and comfortable to use. Disposable absorbent articles of this type generally include a fluid permeable topsheet material, an absorbent core and a fluid impermeable backsheet material. Various forms, sizes and thicknesses of the products have been investigated to make them more comfortable and convenient to use.

Recently, research on such disposable absorbent products has focused mainly on the absorbent capacity of the product. As a result, various absorbent polymers having a large absorbency have been developed. Such known absorbent polymers (also known as hydrogel forming absorbent polymers) can absorb about 30 to 60 g of water per gram of polymer.

More recently, research has focused on removing odors and preventing skin diseases such as dermatitis, rash and redness caused by wearing a disposable absorbent product for a relatively long time. Many body fluids have an unpleasant odor or produce odors when in contact with air and / or bacteria for a long time. In addition, urine and / or other secretions absorbed in the absorbent product are converted to ammonia by the urease produced by the skin bacterial group, ie the general microbial group in the skin. This ammonia results in dermatitis, rash and / or other forms of skin irritation. In infants, these skin diseases are serious medical problems that can lead to severe death.

Antimicrobials and fungicides are chemical compositions used to prevent microbial contamination and degradation of products, materials and systems. Specific applications of antimicrobials and antimicrobial compositions include, for example, cosmetics, fungicides, disinfectants, wood preservatives, food, animal feed, cooling water, metalworking fluids, hospital and medical applications, plastics and resins, petroleum, pulp and paper, textiles, Latex, adhesives, leather, paint slurries and disposable diapers.

For example, Japanese Patent No. 92-17058 discloses a disposable diaper is disclosed to prevent the occurrence of diaper rash caused by the growth of parasitic organisms such as E. coli bacilli (Colibacillus) and Candida (Candida) bacteria. The disclosed disposable diaper consists of a water permeable topsheet, a water impermeable backsheet and a water absorbent layer sandwiched between these sheets. The water absorbent layer also contains a) polyacrylate polymers, starch-acrylonitrile graft copolymer hydrolysates, starch-acrylic acid graft copolymers, polyvinyl alcohol-acrylate copolymers, crosslinked acrylates and crosslinkers. Ammonia absorbing, water absorbing organic polymers selected from the group consisting of polymers prepared by further crosslinking and modified carboxymethyl cellulose; And (b) benzalkonium chloride and / or chlorhexidine gluconate contained in the water absorbent organic polymer. This document also describes the mixing of fungicides with starting materials of organic polymers (e.g. particulate silicon dioxide, copolymers (e.g. crosslinked potassium polyacrylates) and crosslinkers (e.g. ethylene glycol diglycidyl)). Formation of organic polymer / bactericide materials is disclosed. The resulting mixture is then heated to cause a crosslinking reaction to form a crosslinking structure, wherein the fungicide is incorporated into the structure.

The diaper disclosed in Japanese Patent No. 92-17058 is said to absorb ammonia contained in the wearer's urine by an organic polymer, and fungicides inhibit the production of ammonia by bacteria (formed by decomposition of urea contained in urine). Applicant has found a disadvantage of this technique.

For example, because fungicides are introduced into the polymer, they do not begin to function until the polymer is swollen by urine. In other words, the product does not exhibit immediate efficacy, for example when urinating.

In addition, water-absorbent polymers (whether prepared as described in Japanese Patent No. 92-17058 or without introducing a fungicide into the polymer) tend to generate dust during manufacture. This dust generation is a health hazard for workers who inhale dust and has some disadvantages, such as the need to clean the machine more to remove the dust and the product being lost in the form of undesired dust.

Based on the foregoing, there is a need for an antimicrobial Hydrogel-Forming Absorbent Polymer ('A-HFAP') that exhibits immediate efficacy when a user secretes a body fluid when used in a disposable absorbent product. There is also a need for a method of making A-HFAP that minimizes dust production. There is also a need for an absorbent product containing A-HFAP that retains the antimicrobial agent away from the wearer's skin after wetting.

Summary of the Invention

The present invention relates to an antimicrobial hydrogel forming absorbent polymer comprising a hydrogel forming absorbent polymer and an antimicrobial agent, wherein the hydrogel forming absorbent polymer is coated with an antimicrobial agent. These materials meet the need for a hydrogel-forming absorbent polymer and antimicrobial combination that, when used in disposable absorbent products, exhibits immediate efficacy when the user secretes body fluids.

The present invention also relates to a process for preparing such antimicrobial hydrogel-forming absorbent polymer, which method comprises coating the hydrogel-forming absorbent polymer with an antimicrobial agent. This method satisfies the need for a method of minimizing dust generation associated with the preparation of hydrogel-forming absorbent polymers.

The invention also relates to a disposable absorbent article comprising an antibacterial hydrogel forming absorbent polymer. This structure satisfies the need for an absorbent product that effectively reduces odors and rashes while keeping the active ingredients away from the user's skin.

Those skilled in the art will recognize the above objects and other features, aspects, and advantages of the present invention by viewing the drawings in conjunction with the disclosure and the appended claims.

While the specification concludes with the claims specifically pointed out and specifically claimed in the present invention, it is believed that the present invention will be better understood upon reading the following description of the preferred embodiments in conjunction with the accompanying drawings. Like reference numerals denote like elements.

1 is a plan view of a disposable diaper embodiment of the present invention having a cut portion to show the underlying structure, wherein the inner surface of the diaper faces the viewer.

FIG. 2 is a cross-sectional view of one embodiment of the disposable diaper of FIG. 1, taken along the transverse centerline 110 of FIG. 1.

3 is an enlarged view of another embodiment on the disposable basis of FIG. 1, corresponding to a portion of FIG. 2. FIG.

4 shows the key elements of the capture test of the final product.

The following are definitions of terms used herein.

'A-HFAP' refers to an antibacterial hydrogel-forming absorbent polymer.

'Body fluid' includes urine, menstrual blood and vaginal excretion.

"Include" means that other steps and components may be added that do not affect the final result. The term includes 'consist of' and 'consist essentially of'.

'Disposable' describes an absorbent product that is not washed or otherwise restored or reused as an absorbent product (ie, discarded after a single use, preferably recycled, composted or disposed in an environmentally friendly manner).

'HFAP' refers to a hydrogel-forming absorbent polymer.

'Integral' absorbent product refers to an absorbent product in which the separate parts are joined together to form a cooperative, so that separate operating parts such as separate holders and liners are not required.

All percentages are by weight of the total composition unless otherwise indicated.

All ratios are by weight unless otherwise noted.

The present invention, in product and method aspects, is described in detail as follows.

The present invention relates to an antimicrobial hydrogel-forming absorbent polymer comprising HFAP and an antimicrobial agent, wherein the HFAP is coated with an antimicrobial agent.

In a preferred embodiment, the weight ratio of HFAP to the antimicrobial agent is from about 100: 0.01 to about 100: 2, more preferably from about 100: 0.02 to about 100: 1, even more preferably from about 100: 0.05 to about 100: 0.5 .

Hydrogel-forming Absorbent Polymer

Water-insoluble water swellable absorbent polymers useful in the present invention are generally referred to as 'hydrogel forming absorbent polymers' (HFAP), 'hydrocolloid' or 'superabsorbent' polymers, and include polysaccharides such as carboxymethyl starch, carboxymethyl cellulose. And hydroxypropyl cellulose); Nonionics such as polyvinyl alcohol and polyvinyl ethers; And cationic systems such as polyvinyl pyridine, polyvinyl morpholinion, N, N-dimethylaminoethyl or N, N-diethylaminopropyl acrylate and methacrylate, and individual quaternary salts thereof. can do. Typically, HFAPs useful in the present invention have a number of anionic functional groups, such as sulfonic acids, more typically carboxy groups. Examples of suitable polymers for use herein are polymers made from polymerizable unsaturated acid-containing monomers. Thus, such monomers include olefinically unsaturated acids and anhydrides containing one or more carbon-carbon olefin double bonds. More specifically, these monomers may be selected from olefinically unsaturated carboxylic acids and acid anhydrides, olefinically unsaturated sulfonic acids and mixtures thereof.

When preparing the HFAP herein, generally small amounts of some non-acid monomers may also be included. Examples of such non-acidic monomers include water-soluble or water-dispersible esters of acid-containing monomers, and monomers containing no carboxylic acid or sulfonic acid groups. Thus, the optional arsenic monomers include carboxylic or sulfonic acid esters, hydroxyl groups, amide groups, amino groups, nitrile groups, quaternary ammonium salt groups, aryl groups (eg, phenyl groups such as those derived from styrene monomers) and Monomers containing the same functional groups may be included. Such scattering monomers are well known materials and are described, for example, in U.S. Patent No. 4,076,663, issued February 28, 1978 to Masuda et al., And U.S., issued December 13, 1977 to Westerman. Patent 4,062,817 is described in more detail.

As the olefinically unsaturated carboxylic acid and carboxylic anhydride monomers, acrylic acid, methacrylic acid, ethacrylic acid, 3-chloroacrylic acid, cyanoacrylic acid, methacrylic acid (crotonic acid), phenylacrylic acid, and acryloxypropionic acid, which are typical of acrylic acid itself. , Sorbic acid, chlorosorbic acid, angelic acid, cinnamic acid, p-chlorocinnamic acid, stearyl acrylic acid, itaconic acid, citroconic acid, mesaconic acid, glutaconic acid, aconitic acid, maleic acid, fumaric acid, tricarboxyethylene And maleic anhydride.

Olefinically unsaturated sulfonic acid monomers include aliphatic or aromatic vinyl sulfonic acids such as vinylsulfonic acid, allyl sulfonic acid, vinyl toluene sulfonic acid and styrene sulfonic acid; Acrylic and methacrylic sulfonic acids such as sulfoethyl acrylate, sulfoethyl methacrylate, sulfopropyl acrylate, sulfopropyl methacrylate, 2-hydroxy-3-methacryloxypropyl sulfonic acid and 2-acrylamide- 2-methylpropane sulfonic acid).

Preferred HFAPs for use in the present invention have carboxy groups. Such polymers include hydrolyzed starch-acrylonitrile graft copolymers, partially neutralized hydrolyzed starch-acrylonitrile graft copolymers, starch-acrylic acid graft copolymers, partially neutralized starch-acrylic acid graft copolymers Copolymers, saponified vinyl acetate-acrylic acid ester copolymers, hydrolyzed acrylonitrile or acrylamide copolymers, slightly reticulated crosslinked polymers of any of the foregoing copolymers, partially neutralized polyacrylic acid, and partially neutralized polyacrylic acid There is a slightly reticulated crosslinked polymer of. These polymers may be used alone or in the form of a mixture of two or more different polymers. Examples of these polymeric materials are disclosed in US Pat. No. 3,661,875, US Pat. No. 4,076,663, US Pat. No. 4,093,776, US Pat. No. 4,666,983 and US Pat. No. 4,734,478.

More preferred polymeric materials for use in the production of HFAP are slightly reticulated crosslinked polymers of partially neutralized polyacrylic acid and starch derivatives thereof. More preferably, HFAP comprises about 50% to about 95%, preferably about 75%, slightly reticulated crosslinked polyacrylic acid (ie, poly (sodium acrylate / acrylic acid)). The network crosslinking makes the polymer substantially water insoluble and partially determines the absorption capacity and extractable polymer content characteristics of HFAP. Methods of network crosslinking of these polymers and typical network crosslinkers are described in more detail in US Pat. No. 4,076,663.

In addition, surface crosslinked HFAP may preferably be used in the present invention. They are more crosslinked near the surface than inside. As used herein, 'surface' describes the outwardly facing boundaries of particles, fibers, and the like. In the case of porous HFAP (eg, porous particles, etc.), exposed internal boundaries may also be included. More crosslinked at the surface means that the degree of functional crosslinking to HFAP near the surface is generally greater than the degree of functional crosslinking to the polymer inside.

The gradient of crosslinking from the surface to the interior can vary in depth and appearance. Thus, for example, the depth of the surface crosslinking can be shallow so that it transitions relatively rapidly to lower levels of crosslinking. Alternatively, for example, the depth of the surface crosslinking can be a significant fraction of the dimensions of the HFAP and transition to a wider range.

Depending on size, shape, porosity and functionality, the degree and gradient of surface crosslinking may vary within a given HFAP. For granular HFAP, surface crosslinking may vary depending on particle size, porosity, and the like. As the surface: volume ratio in HFAP changes (eg, between small and large particles), it is not unusual for the total amount of crosslinking in the material to change (eg, smaller particles are larger).

Surface crosslinking generally occurs after the final boundary of the HFAP is essentially defined (eg, by grinding, extrusion, foaming, etc.). However, surface crosslinking can be carried out simultaneously with generating the final boundary. In addition, some additional changes may occur at the boundary even after the surface crosslinking is introduced.

Many methods for introducing surface crosslinks are disclosed in the art. These are (i) bifunctional or multifunctional reagent (s) capable of reacting with functional groups present in HFAP (eg, glycerol, 1,3-dioxolan-2-one, polyvalent metal ions, polyquaternary amines) Applying to the surface of HFAP; (ii) in order to increase the amount of crosslinking on the surface of the HFAP, a method of applying to the surface of the HFAP other reagents and multifunctional reagents that can react with functional groups that may be present in the HFAP (e.g., Adding monomers and crosslinkers and initiating secondary polymerization; (iii) no additional polyfunctional reagent, but additional reaction between existing components present in the HFAP during or after the first polymerization process, in order to cause more crosslinking at or near the surface of the HFAP. Method of inducing (s) (e.g., heating to induce the formation of anhydride and / or ester crosslinks and suspension polymerization between polymer carboxylic acid and / or hydroxyl groups present, wherein the crosslinker is essentially Present in greater quantities near the surface of HFAP); And (iv) adding other materials to the surface of the HFAP to cause more crosslinking or otherwise reduce the surface modification of the resulting hydrogel. These surface crosslinking methods can be used simultaneously or in combination. In addition to the crosslinker, other components may be added to the surface of the HFAP to assist or control the distribution of crosslinks (eg, development and penetration of the surface crosslinker).

General methods suitable for carrying out the surface crosslinking of HFAP according to the present invention are described in US Pat. No. 4,541,871 to Obayashi, issued September 17, 1985; International Patent Publication No. WO92 / 16565, published October 1, 1992 in the name of Stanley; International Patent Publication No. WO90 / 08789, issued August 9, 1990 in the name of Tai; International Patent Publication No. WO93 / 05080, published March 18, 1993 in the name of Stanley; US Patent No. 4,824,901, issued April 25, 1989 to Alexander; US Patent No. 4,789,861, issued January 17, 1989 to Johnson; US Patent No. 4,587,308, issued May 6, 1986 to Makita; US Pat. No. 4,734,478, issued March 29, 1988 to Tsubakimoto; US Patent No. 5,164,459, issued November 17, 1992 to Kimura et al .; German Patent Publication No. 4,020,780, issued August 29, 1991 in the name of Damen; And European Patent Publication No. 509,708, published October 21, 1992 in the name of Gartner.

HFAP preferably consists of one type (ie homogeneous), but polymer mixtures may also be used in the present invention. For example, slightly reticulated crosslinked polymers of starch-acrylic acid graft copolymers and partially neutralized polyacrylic acids can be used in the present invention.

HFAP particles used in the present invention may have a wide range of sizes, shapes, and / or morphologies. HFAP particles do not have a large ratio of maximum and minimum dimensions (eg, granules, powders, fines, intergranular aggregates, intergranular crosslinked aggregates, etc.) and may have the form of fibers, foams, and the like. HFAPs may also include mixtures with small amounts of one or more additives such as powdered silica, surfactants, glues, binders, and the like. The components of this mixture may be physically and / or chemically combined such that the hydrogel forming polymer component and the hydrogel non-forming polymer additive cannot be easily physically separated.

HFAPs may be essentially nonporous or have substantial internal porosity.

For particles as described above, the particle diameter is defined as the dimension determined by sieve size analysis. Thus, for example, particles that are subjected to a US standard test body (eg, No. 25 US Series Alternate Sieve Designation) having an opening of 710 microns is larger than 710 microns. Particles that are considered to have a particle diameter and which pass through a sieve having an opening of 710 microns and have a sieve having an opening of 500 microns (e.g., a US 35 series alternate sheave degration) have a particle diameter of 500 to 710 microns. Particles are passed through a sieve having an opening of 500 microns and are considered to have a particle diameter of less than 500 microns. The median particle size of a given sample of hydrogel-forming absorbent polymer particles is defined as the particle size that divides the sample in half by mass; that is, half of the sample by weight will have a particle size smaller than the median mass size, and half of the sample It will have a particle size larger than the median mass. When the 50% mass value does not match the opening size of the US standard test body, the standard particle size graphing method (the cumulative weight percent of the particle sample over or passing through the opening size of a given Relative to the sieve opening size, plotted on probability paper). This method of determining the particle size of hydrogel-forming absorbent polymer particles is also described in US Pat. No. 5,061,259, issued October 29, 1991 to Goldman et al.

For HFAP particles useful in the present invention, the size of the particles will generally be from about 1 to about 2000 microns, more preferably from about 20 to about 1000 microns. The mass median particle size will generally be about 20 to about 1500 microns, more preferably about 50 to about 1000 microns, even more preferably about 100 to about 800 microns.

Within this particle size range, it may be desirable to select large or small particles as needed for fast or slow absorption kinetics. For example, for nonporous particles, the swelling rate will generally decrease with increasing particle diameter. It is desirable to select large or small particles to increase gel layer permeability (ie, to increase the Saline Flow Conductivity (SFC) value) or to select a narrow size fraction of large or small particles of the bulk polymer. can do. For some HFAP particles, a narrow size range fraction having a generally large particle size within the size ranges described above may have other HFAP properties, such as performance under pressure (PUP) capacity and amount of extractable polymer. Without deterioration, it was found to have larger SFC values. Thus, for example, it may be useful to use a size fraction having a mass median size in the range of about 500 to about 710 microns, where only the minimum mass fraction of the particles is greater than about 710 microns or less than about 500 microns. Has Alternatively, wider size fractions where particles generally have a size of about 150 microns to about 800 microns can be useful.

Antimicrobial

Antimicrobial agents useful in the present invention may be chemicals that can prevent the growth of microorganisms or kill microorganisms, bind to HFAP, and more preferably bind to the surface of HFAP. Preferred antimicrobial agents are those which can prevent or kill the growth of microorganisms typically found in body fluids, more preferably body fluids typically collected by disposable absorbent products. Non-limiting examples of preferred antimicrobials include quaternary ammonium, phenol, amide, acid and nitro compounds, and mixtures thereof, more preferably quaternary ammonium, acid and phenol, and even more preferably quaternary ammonium compounds.

Non-limiting examples of preferred quaternary ammonium compounds include 2- (3-anilinovinylrul) -3,4-dimethyl-oxazolinium iodide, alkylisoquinolinium bromide, benzalkonium chloride, benzethonium chloride Cetylpyridium chloride, chlorhexidine gluconate, chlorhexidine hydrochloride, lauryl trimethyl ammonium, methylbenzethium chloride, steartrimethylammonium chloride, 2,4,5-trichlorophenoxide and mixtures thereof, more preferably benz Alkonium chloride and chlorohexidine gluconate, even more preferably benzalkonium chloride.

Non-limiting examples of preferred phenolic compounds include benzyl alcohol, p-chlorophenol, chlorocresol, chloroxylenol, cresol, o-cymen-5-ol (BIOSOL), hexachlorophene, hinokthiol, isopropylmethylphenol, Parabens (parabens with methyl, ethyl, propyl, butyl, isobutyl, isopropyl and / or sodium methyl substituents), phenethyl alcohol, phenol, phenoxyethanol, o-pinylphenol, resorcin, resorcin monoacetate, sodium Parabens, sodium phenolsulfonate, thioxolone, 2,4,4'-trichloro-2'-hydroxydiphenyl ether, zinc phenolsulfonate and mixtures thereof, more preferably sodium paraben.

Non-limiting examples of preferred amides include diazolidinyl urea, 2,4-imidazolidinedione (hydantoin, HYDANTOIN), 3,4,4'-trichlorocarbanilide, 3-trifluoromethyl-4 , 4'-dichlorocarvanide, undecylenic acid monoethanolamide and mixtures thereof, more preferably diazolidinyl urea and 2,4-imidazolidinedione, even more preferably 2,4-imida There is zolidinedione.

Non-limiting examples of preferred acids include benzoate, benzoic acid, citric acid, dehydroacetic acid, potassium sorbate, sodium citrate, sodium dehydroacetate, sodium salicylate, sodium salicylic acid, sorbic acid, undecylenic acid, zinc undecylenate Nates and mixtures thereof, more preferably benzoic acid, citric acid, salicylic acid and sorbic acid, even more preferably citric acid and sorbic acid.

Non-limiting examples of preferred nitro compounds include 2-bromo-2-nitro-2,3-propanediol (bronopol, BRONOPOL), methyldibromo glutaronitrile and propiolene glycol (mergaard, MERGUARD), And mixtures thereof.

Process for preparing antibacterial hydrogel-forming absorbent polymer

The present invention also relates to a method of making an antimicrobial hydrogel forming absorbent polymer comprising coating HFAP particles with an antimicrobial agent. As used herein, the term 'coating' means that the antimicrobial agent is present in at least a portion of the surface area of the HFAP. Preferably, the antimicrobial agent is applied to the entire surface of the HFAP. Without wishing to be bound by theory, it is believed that the antimicrobial agent binds to the surface of HFAP by Coulomb interaction. When A-HFAP is hydrated, most antimicrobial agents will ionically bind to HFAP. However, some antimicrobials may diffuse into interparticle spaces and fibers.

When the antimicrobial agent is in the form of small particles or powders, the antimicrobial agent may be applied by various techniques and machines used to apply (eg, coat) the material to other materials. In other cases, where the antimicrobial agent is in liquid form, the antimicrobial agent may be applied by various techniques and machines used to apply the liquid to the material (eg, coated on HFAP). As a result, the A-HFAP of the present invention can be obtained as described above.

In a preferred embodiment, the antimicrobial agent is dissolved in a solvent to make a solution. The antimicrobial agent can be dissolved in the solvent by various techniques and machines known in the art used to dissolve the material in the solvent. In a more preferred embodiment, an inorganic solvent is used as the solvent, preferably water is used. Preferably, the concentration of the antimicrobial agent in the solution is about 2-25 wt%, more preferably about 5-15 wt%.

In certain embodiments, antibacterial agents that are insoluble in organic solvents may be used. In a more preferred embodiment, a polar organic solvent is used as the solvent. In this embodiment, a mixed solvent of hydrophilic organic solvent and water is used as the solvent of the antimicrobial agent. Non-limiting examples of preferred organic solvents include low molecular weight alcohols such as methanol, ethanol or propanol, acetone, dimethylformamide (DMF), dimethylsulfoxide (DMSO), hexylmethyl phosphate triamide (HMPT) and their There is a mixture. In another preferred embodiment, nonpolar solvents such as hexane, toluene, xylene and benzene can be used as one of the organic solvents.

After preparing the solution, the solution is applied to HFAP to make a discontinuous mixture. More specifically, an amount of solution is applied to HFAP. By various techniques and machines used to apply the solution to the material, including coating, dumping, entering, dropping, spraying, spraying, condensing or dipping the liquid mixture onto the absorbent gelling particles By application, HFAP can be partially coated or fully coated with antimicrobial agent. Thus, in discontinuous mixtures, the solution will be present (ie coated) at least a portion of the surface area of the HFAP. Preferably, the solution is present on the entire surface of the HFAP particles.

The amount of antimicrobial agent sufficient to exhibit effective antimicrobial activity depends on a number of factors, including the chemical composition of the HFAP and the physical form of the HFAP (eg, the particle size of the HFAP), and the chemical composition and molecular weight of the antimicrobial agent as well as the method of applying the antimicrobial agent. Can vary.

After preparing the discontinuous mixture, at least some solvent is removed from the discontinuous mixture. Preferably, at least about 80%, more preferably more than 95%, and most preferably about 100% of solvent is removed from the discontinuous mixture. Removal of the solvent can be performed by various techniques and machines used to separate or remove the liquid from the liquid-solid mixture, including evaporation, filtration, washing or a combination thereof.

In a preferred embodiment, the antimicrobial agent is applied to the HFAP after the surface crosslinking treatment of the HFAP particles. On the other hand, in other embodiments the antimicrobial agent is applied to the HFAP prior to the surface crosslinking treatment of the HFAP. In another embodiment, the application of the antimicrobial agent and the crosslinking treatment may be performed simultaneously.

In a preferred embodiment, the resulting A-HFAPs can have various shapes and sizes. For example, the absorbent material may typically take the form of particles, sheets, films, cylinders, blocks, fibers, filaments or other shaped elements. More preferably, the absorbent material is granular.

Absorbent products using antibacterial hydrogel-forming absorbent polymers

The A-HFAP according to the present invention can be used for various purposes for various purposes. For example, A-HFAP may be a packaging container; Drug administration device; Wound cleaning devices; Burn treatment apparatus; Ion exchange column materials; Building materials; Agricultural or horticultural agricultural materials (eg nursery or moisturizing materials); And industrial applications such as sludge or oil dehydrating agents, materials for preventing dew formation, desiccants and moisture control materials.

Because of the unique absorbency and antimicrobial properties of A-HFAP of the present invention, A-HFAP is particularly suitable for use as an absorbent core of absorbent articles, in particular disposable absorbent articles. As used herein, the term 'absorbent product' refers to a product that absorbs and contains body fluids, and more specifically, refers to a product that absorbs and contains various fluids that are discharged from the body located opposite or in proximity to the wearer's body. .

Generally, the absorbent article comprises (a) a liquid permeable topsheet positioned adjacent to the wearer's body; (b) a liquid impermeable backsheet positioned away from the wearer's body and adjacent to the wearer's garment; And (c) an absorbent core positioned between the top sheet and the back sheet. The absorbent core comprises at least one of the A-HFAPs of the invention described above. Preferably, the absorbent core further comprises a substrate web to which the absorbent material is attached. Alternatively, the absorbent core further includes an envelope web surrounding the absorbent material. In another embodiment, the absorbent core further comprises two layers of tissue, wherein the absorbent material is distributed between the two layers of tissue.

In a more preferred embodiment, the A-HFAP in the absorbent core has a basis weight of about 60 to about 1500 g, more preferably about 100 to about 1000 g, most preferably about 150 to about 500 g per m 2 of absorbent material.

In some preferred embodiments, the absorbent core or absorbent member further comprises fibers or fluff pulp (fibrous material or fibrous material), more specifically non-absorbent gelling fibers. Such fibrous materials can be used as reinforcing members in absorbent cores to increase the fluid handleability of the cores, as well as used as co-absorbents for absorbent polymers. Preferably, the absorbent core or absorbent member comprises about 40 to about 100 weight percent A-HFAP and about 0 to about 60 weight percent non-absorbent gelling fiber material distributed in the absorbent material.

In a preferred embodiment, the concentration of A-HFAP is at least 40% by weight, more preferably about 60-100% by weight in at least one region of the core or absorbent member. In a more preferred embodiment, the absorbent member comprises a fibrous matrix in which A-HFAP is distributed.

Fibrous materials suitable for use in conventional absorbent articles can be of any type used in the absorbent core or absorbent member of the present invention. Specific examples of such fibrous materials include cellulose fibers, improved cellulose fibers, rayon, polypropylene and polyester fibers such as polyethylene terephthalate (Dacron, DACRON), hydrophilic nylon (hydrofill, HYDROFIL). Examples of other fibrous materials for use in the present invention include, for example, surfactant treated or silica treated thermoplastic fibers derived from polyolefins (such as polyethylene or polypropylene), polyacryl, polyamide, polystyrene, polyurethane, and the like. Hydrophilized hydrophobic fibers such as In fact, hydrophilized hydrophobic fibers are not very absorbent by themselves and do not provide a web with sufficient absorbent capacity for use in conventional absorbent structures, but are suitable for use in absorbent cores because of their good wickability. This is because, in the case of the absorbent core of the present invention, the absorbent capacity of the fiber is as important as the absorbent capacity of the fiber, although the absorbency of the fiber is not as important as the absorbent capacity of the fiber material itself due to the high fluid absorption rate and the absence of gel barrier properties of the absorbent core. . Synthetic fibers are generally preferred for use as the fiber component of the absorbent core in the present invention. Most preferred are polyolefin fibers, preferably polyethylene fibers.

Other cellulosic fiber materials that may be useful in certain absorbent cores or absorbent members of the present invention are chemically strengthened cellulosic fibers. Preferred chemically strengthened cellulose based fibers are reinforced, twisted, curled cellulose based fibers that can be prepared by internally crosslinking cellulose fibers with a crosslinking agent. Suitable reinforced, twisted and curled cellulosic fibers useful as the hydrophilic fibrous material of the present invention are described in US Pat. No. 4,888,093, issued December 19, 1989 to Dean et al., Herron et al. United States Patent No. 4,889,595, issued March 26 to Schoggen et al. US Patent No. 4,889,596, issued December 26, 1989 to Bourbon et al. US Pat. No. 4,898,647, issued February 6, 1990 to Patent No. 4,889,597 and Moore et al.

Preferred embodiments of disposable absorbent articles are diapers. As used herein, the term 'diaper' refers to a garment generally worn by infants and incontinence, worn around the lower body of the wearer. Preferred diaper forms for diapers comprising absorbent cores are described in their entirety in US Pat. No. 3,860,003 to Buell, issued January 14, 1975. Another preferred form of the disposable diaper herein is also U.S. Patent 4,808,178 to Aziz et al. On 28 February 1989, US Pat. No. 4,695,278 to Lawson on September 22, 1987 US Pat. No. 4,816,025, issued March 28, 1989 to Foreman, and US Pat. No. 5,151,092, issued September 29, 1992 to Buell et al.

A preferred embodiment of the absorbent article of the present invention is the diaper 20, which is the unitary disposable absorbent article shown in FIG. 1 is a plan view of the diaper 20 of the present invention in an unfolded, unshrunk state (i.e., with shrinkage due to elasticity removed), showing a portion of the structure to more clearly show the structure of the diaper 20. FIG. After cutting, the inner surface 40, which is part of the diaper 20 facing the wearer, faces the viewer. As shown in FIG. 1, the diaper 20 preferably includes a liquid permeable top sheet 24, a liquid impermeable backsheet 26 connected to the top sheet, and a top sheet 24 and a back sheet 26. Containment assembly 22 comprising an absorbent core 28 positioned in the. Absorbent core 28 has a pair of opposing longitudinal edges 60, an inner surface 62, and an outer surface 64. The diaper preferably comprises a side panel 30; Elasticized leg cuffs 32; Elasticized waistband 34; And preferably a fastening system 36 comprising a pair of fastening members 37 and a landing member 38.

The diaper 20 in FIG. 1 has an inner surface 40 (facing the observer in FIG. 1), an outer surface 42 opposite the inner surface 40, a rear waist region 44, and a front waist region opposite the rear waist region 44. (46), the crotch region 48 located between the posterior waist region 44 and the anterior waist region 46, and the outer perimeter or edge of the diaper 20 (side edges are indicated by (50) and distal edges). Is shown as having a perimeter defined by (52). The inner surface 40 of the diaper 20 includes a portion of the diaper 20 positioned adjacent to the wearer's body during use (ie, the inner surface 40 generally includes at least a portion and a top surface of the top sheet 24). Formed by other components connected to the sheet 24). The outer surface 42 includes a portion of the diaper 20 that is remote from the wearer's body (ie, the outer surface 42 generally includes at least a portion of the backsheet 26 and other components connected to the backsheet 26). Formed by). As used herein, the term 'connection' refers to a form in which one element is directly attached to another element by directly attaching one element to the other element, and by attaching one element to the intermediate member (s) and then attaching it to the other element. Includes an indirect fixation of an element to another element. The back waist region 44 and the front waist region 46 extend from the distal edge 52 of the perimeter to the crotch region 48.

The diaper 20 also has two centerlines, a longitudinal centerline 100 and a transverse centerline 110. As used herein, the term " longitudinal " refers to a diaper 20 that is generally aligned (e.g., substantially parallel) in a vertical plane that divides the wearer into the left and right half when the wearer is standing and wearing the diaper 20. In-plane lines, axes, or directions. As used herein, the terms "lateral" and "lateral" are used interchangeably and refer to the line, axis or direction in the diaper surface (dividing the wearer into the first half and the second half of the body) which is generally perpendicular to the longitudinal direction.

In FIG. 1, the containment assembly 22 of the diaper 20 is shown to include a body (body) of the diaper 20. The containment assembly 22 preferably comprises an upper sheet 24, a rear sheet 26, and an absorbent core 28 having a pair of opposing longitudinal edges 60, an inner surface 62 and an outer surface 64. do. The inner surface 62 generally faces the wearer's body and the outer surface 64 generally faces away from the wearer's body. If the absorbent article includes separate holders and liners, containment assembly 22 generally includes a holder and a liner (ie, containment assembly 22 includes one or more layers of material defining a holder and a liner Includes absorbent composites such as topsheet, backsheet and absorbent core). In the unitary absorbent article, the containment assembly 22 preferably comprises a topsheet 24, a backsheet 26 and an absorbent core 28 of the diaper having other features added to form a composite diaper structure. .

1 illustrates a preferred embodiment of a containment assembly 22 in which the top sheet 24 and back sheet 26 have a larger length and width dimension than the absorbent core 28 as a whole. The top sheet 24 and back sheet 26 extend beyond the edge of the absorbent core 28 to form the periphery of the diaper 20. The topsheet 24, backsheet 26 and absorbent core 28 can be assembled in a variety of well known forms, examples of the containment assembly form being Kenneth B. Buell, which is incorporated herein by reference. U.S. Patent Nos. 3,860,003 and Buel, issued September 29, 1992, entitled "Contractible Side Portions for Disposable Diaper," issued January 14, 1975 Absorbent Article With Dynamic Elastic Waist Feature Having A Predisposed Resilient Flexural Hinge, generally described in US Pat. No. 5,151,092.

Absorbent core 28 may be any absorbent member that is generally compressible, adherent, non-irritating to the wearer's skin and capable of absorbing and retaining liquids (eg, urine and other specific body secretions). As shown in FIG. 1, the absorbent core 28 has a garment facing surface, a body facing surface, a pair of side edges and a pair of waist edges. Absorbent core 28 can be made in a variety of sizes and shapes (eg, rectangular, hourglass, T-shaped, asymmetric, etc.), and in addition to including the A-HFAP of the present invention, are typically disposable It may also comprise various liquid-absorbent materials used in diapers and other absorbent articles, such as crushed wood pulp, commonly referred to as airfelt. Examples of other suitable absorbent materials include creped cellulose wadding; Meltblown polymers, including coforms; Chemically reinforced, modified or crosslinked cellulose fibers; Tissue, including tissue wraps and tissue laminates; Absorbent foams; Absorbent sponges; Superabsorbent polymers; Absorbent gelling materials; Or equivalent materials or combinations thereof.

The shape and structure of the absorbent core 28 may also vary (eg, the absorbent core may have varying caliper bands, hydrophilic gradients, superabsorbent gradients, or lower average density and lower average basis weight capture bands). Or may comprise one or more layers or structures). In addition, the size and absorbent capacity of the absorbent core 28 may also vary to suit the wearer from infant to adult. However, the overall absorbent capacity of the absorbent core 28 should depend on the intended fill of the diaper 20 and the intended use.

One embodiment of the diaper 20 has an asymmetric modified T-shaped absorbent core 28 that is ear shaped in the front waist region but is generally rectangular in the rear waist region. An example of an absorbent structure for use as the absorbent core 28 of the present invention, which has been widely accepted and commercially successful, is 'High Density', issued September 9, 1986 to Weisman et al. US Patent No. 4,610,678, entitled Absorbent Structures; US Patent No. 4,673,402, entitled Absorbent Articles With Dual-Layered Cores, issued June 16, 1987 to Weisman et al .; To US Patent Nos. 4,888,231 and Alemany et al., Entitled 'Absorbent Core Having A Dusting Layer', issued December 19, 1989 to Angstadt. In US Patent No. 4,834,735 entitled 'High Density Absorbent Members Having Lower Density and Lower Basis Weight Acquisition Zones', issued May 30. Described. Absorbent cores are also disclosed in U.S. Patent Nos. 5,234,423, entitled Absorbent Article With Elastic Waist Feature and Enhanced Absorbency, issued August 10, 1993 to Alemani et al. United States Patent No. 5,147,345 entitled High Efficiency Absorbent Articles For Incontinence Management, issued to Young, LaVon and Taylor on September 15, 1992 As described herein, a dual core system containing a capture / distribution core of chemically strengthened fibers located over an absorbent storage core is included.

The topsheet 24 is preferably located adjacent the inner surface 62 of the absorbent core 28 and is preferably the backsheet 26 by attachment means (not shown) as is well known in the art. Is connected to. Suitable attachment means will be described in connection with connecting the backsheet 26 to the absorbent core 28. In a preferred embodiment of the present invention, the topsheet 24 and the backsheet 26 are directly connected to each other at the periphery of the diaper, which are indirectly connected to each other by being directly connected to the absorbent core 28 by suitable attachment means.

The topsheet 24 is preferably flexible, has a soft feel, and is non-irritating to the wearer's skin. In addition, the topsheet 24 is preferably liquid permeable to easily permeate liquid (eg, urine) through its thickness. Suitable topsheets 24 include woven and nonwoven fabrics; Polymeric materials such as perforated thermoplastic films, perforated plastic films, and hydroformed thermoplastic films; Porous foams; Reticulated foam; Reticulated thermoplastic film; And a wide variety of materials such as thermoplastic scrims. Suitable fabrics and nonwovens can be made of natural fibers (eg wood fibers or cotton fibers), synthetic fibers (eg polyester, polypropylene or polyethylene fibers) or a combination of natural fibers and synthetic fibers. The topsheet 24 is preferably made of a hydrophobic material that passes through the topsheet 24 to separate (ie, prevent rewetting) the wearer's skin from the liquid contained in the absorbent core 28. If the topsheet 24 is made of hydrophobic material, at least the top surface of the topsheet is hydrophilic to allow liquid to move more quickly through the topsheet. This reduces the tendency for body fluids to flow out of the top sheet 24 without being absorbed by the absorbent core 28 past the top sheet 24. The topsheet 24 can be treated with a surfactant to become hydrophilic. Suitable methods for treating the topsheet 24 with a surfactant include spraying a surfactant onto the topsheet 24 material and immersing the topsheet material in the surfactant. A more detailed discussion of these treatments and hydrophilicity is given in the United States, entitled Absorbent Articles with Multiple Layer Absorbent Layers, issued to Reising et al. On 29 January 1991. Patent No. 4,988,344 and US Patent No. 4,988,345, entitled Absorbent Articles with Rapid Acquiring Absorbent Cores, issued January 29, 1991 have.

Another preferred topsheet includes a perforated film. Perforated molded films are preferred for topsheets because they are located in front of body secretions but are nonabsorbent and reduce the tendency for liquid to pass back and rewet the wearer's skin. Thus, the surface of the molded film in contact with the body remains dry, thereby reducing body dirt and giving the wearer a more comfortable feel. Suitable molded films are described in US Pat. No. 3,929,135, entitled Absorptive Structures Having Tapered Capillaries, issued to Thomson on December 30, 1975; United States Patent No. 4,324,246, entitled Disposable Absorbent Article Having A Stain Resistant Topsheet, issued April 13, 1982 to Mulan et al .; US Patent No. 4,342,314, entitled "Resilient Plastic Web Exhibiting Fiber-like Properties," issued to Radel et al. On August 3, 1982; Macroscopically Expanded Three-Dimensional Plastic Web Exhibiting Non-Glossy Visible Surface, issued July 31, 1984 to Ar et al. and Cloth-Like Tactile Impression; US Pat. No. 4,463,045; And US Pat. No. 5,006,394, entitled 'Multilayer Polymeric Film,' issued April 9, 1991 to Baird.

The backsheet 26 of the present invention is generally a part of the diaper 20 located away from the wearer's skin, whereby the product absorbed by the absorbent core 28 and contained therein is in contact with the diaper 20 (eg, bed sheet). And undergarment). Accordingly, the backsheet 26 is preferably impermeable to liquids (eg, urine) and is preferably made from thin plastic films, although other flexible liquid impermeable materials may be used. (The term 'flexible' as used herein refers to a material that is flexible and easily conforms to the overall shape and contour of the human body.) However, the backsheet 26 allows vapor to escape from the diaper. Suitable materials for the backsheet 26 are thermoplastic films, preferably comprising polyethylene or polypropylene, having a thickness of about 0.012 mm to about 0.051 mm (about 0.5 mil to about 2.0 mil).

The backsheet 26 of the present invention may comprise a single member, such as the film described above, or may comprise a plurality of materials connected together to form the backsheet 26. For example, the backsheet may comprise one film or It may have a central region 74 including other members, and one or more outer regions 76 connected to the central region 74, including the same or different films or other materials. In one preferred embodiment, the backsheet 26 comprises a central region 76 comprising a liquid permeable non-perforated film and two opposing outer regions 76 comprising an air permeable perforated film. Means for connecting any portions of such backsheet may include means known in the art, such as adhesive bonding, thermal bonding, pressure bonding, thermal and pressure bonding, and ultrasonic bonding. The backsheet 26 may also comprise a plurality of layers of materials connected to one another to form a laminate. If the backsheet 26 is a laminate, the layers need not be uniform throughout the backsheet. For example, the central region 74 of the backsheet 26 may include more layers or different layers of material than the outer region 76.

The backsheet 26 is preferably located adjacent the outer surface 64 of the absorbent core 28 and is preferably connected to the absorbent core by suitable attachment means known in the art. For example, the backsheet 26 may be secured to the absorbent core 28 by a uniform, continuous adhesive layer, patterned adhesive layer, or a series of separate adhesive lines, spirals or dots. The adhesive, found to be satisfactory, is manufactured by H. B. Fuller Company, St. Paul, Minn., And sold under the HL-1258. An example of a suitable attachment means comprising an adhesive filament of an open pattern network is named Disposable Waste-Containment Garment, issued to Minetola et al. On March 4, 1986. US Pat. No. 4,573,986. Other suitable means of attachment, including some adhesive filament lines swirling in a spiral pattern, are described in US Pat. No. 3,911,173 to Sprague, Jr., issued October 7, 1975; US Patent No. 4,785,996, issued November 22, 1978 to Zieker et al .; And the machines and methods shown in US Pat. No. 4,842,666, issued June 27, 1989 to Werenicz. Each of these patents is incorporated herein by reference. Alternatively, the attachment means may comprise thermal bonding, pressure bonding, ultrasonic bonding, dynamic mechanical bonding, or other suitable attachment means or combinations of these attachment means known in the art.

Embodiments of the invention are also contemplated in which the absorbent core is not connected to the backsheet 26 and / or the topsheet 24 to further increase the stretchability in the front waist region 46 and the back waist region 44. . Another embodiment is also contemplated where additional members, such as liquid impermeable barrier (s) (not shown), are located between the outer surface 64 of the absorbent core 28 and the backsheet 28. This blocking member may or may not be connected to the absorbent core 28. In addition, the backsheet 26 may or may not be connected to the barrier (s) located between the backsheet 26 and the absorbent core 28.

Another preferred embodiment of the disposable absorbent product is a sanitary ware. Preferred physiological products are U.S. Patent 4,285,343, issued to McNair on August 25, 1981, U.S. Patent 4,608,047 to Mattingly, issued August 26, 1986, and Van Tilburg. Tilburg), perforated topsheets of molded films disclosed in US Pat. No. 4,687,478, issued August 18,1987.

Preferred physiological products have been filed Nov. 30, 1992 and commonly assigned to Morita, Yasuko, under the name of the co-pending 'Absorbent Article Having Elasticized Side Flaps'. As described in US patent application 984,071 (Document No. JA-09RM), it may include wings, side flaps, and other structures and elements.

Particularly preferred disposable absorbent articles comprising A-HFAP have reduced surface wettability. This product keeps the antimicrobial agent away from the wearer's skin after wetting. Disposable absorbent articles comprising a backsheet, a topsheet, a capture / distribution layer, and an absorbent core comprising the A-HFAP of the present invention have a capture rate (determined by the test method discussed below) of the entire final product upon first ejection. Is about 1.9 ml / sec or more and at the time of the fourth jet, it is about 0.3 ml / sec or more. The fold up height of such absorbent articles is preferably less than about 9.9 mm, more preferably less than about 6 mm, per pad. Preferably, the topsheet of such a product does not retain fluid from about 0.05 g to more than about 1 g, more preferably up to about 0.5 g of fluid, as measured by the wetness test of the final product (discussed later). More preferably about 0.2 g or less of fluid, even more preferably about 0.15 g or less of fluid.

2, an embodiment of a disposable absorbent article in the form of a diaper is provided. 2 is a cross-sectional view of the embodiment of the disposable diaper of FIG. 1, taken along the transverse centerline 110 of FIG. 1. This figure shows a partial cross-sectional view of the backsheet 26, the core cover 22, the absorbent core 28, the topsheet 24 and the resilient leg cuffs 32. This embodiment differs from the embodiment shown in FIG. 1 in that an additional element capture / distribution layer 105 has been added.

3 is an enlarged view of another embodiment on the disposable basis of FIG. 1, corresponding to a portion of FIG. 2. FIG. In this embodiment, the topsheet 24 includes a first topsheet layer 115 and a second topsheet layer 120. The first top sheet layer 115 and the second top sheet layer 120 are preferably thermally bonded to each other. The capture / distribution layer 105 includes a first capture / distribution layer 125 and a second capture / distribution layer 130. The first capture / distribution layer 125 is preferably helical glue bonded to the second topsheet layer 120. Preferably, the first capture / distribution layer 125 and the second capture / distribution layer 130 are not bonded to each other.

The embodiment described in FIG. 2 or 3 exhibits a tendency to reduce surface wetness, which results in keeping the antimicrobial agent away from the wearer's skin after wetting. In other words, this embodiment provides an opportunity for A-HFAP, possibly A-HFAP, containing an antimicrobial agent to come into contact with, for example, urine, which flows back into the user's skin, causing the antimicrobial agent to come into contact with the user's skin. Decrease.

Preferred topsheet 24 and capture / distribution layer 105 materials for such reduced surface wetness absorbent articles include the following.

A preferred topsheet 24 material is a P-8 nonwoven available from Fiberweb North America, Inc., Simpsonville, South Carolina. It consists of about 2.2 dtex of polypropylene fiber and contains an easily removable surfactant (spin finish) (i.e. very hydrophilic when initially contaminated by fluid, but if repeatedly wetted, the base polypropylene Essentially hydrophobic, such as about 20 to 22 g / m 2 of conventional thermally bonded carded web.

More preferably, the topsheet 24 material is S-2355, available from Havix Co., Japan. It is a two-layer composite material consisting of two kinds of synthetic surfactant treated bicomponent fibers using carding and venting techniques. The first topsheet layer 115 preferably has polypropylene / polypropylene bicomponent fibers such as low melting point polypropylene in the sheath of the fiber and high melting point polypropylene in the core of the fiber. It is a fiber. The second topsheet layer 120 preferably is a polyethylene / polyethylene terephthalate bicomponent fiber, for example a fiber having a low melting polyethylene in the sheath of the fiber and a high melting point, high elastic polyethylene terephthalate in the core of the fiber. to be. The first topsheet layer 115 preferably has a weak hydrophilic surfactant, and the second topsheet preferably has a normal hydrophilic surfactant. The total basis weight of a typical material is about 20 to 22 g / m 2.

Preferably, the capture / distribution layer 105 is a carded resin bonded, such as FT-6860, available from Polymer Group, Inc., North America, Randishville, NJ. High loft nonwovens. These consist of 6dtex polyethylene terephthalate fibers and have a basis weight of about 43 g / m 2. Alternatively, the capture / distribution layer 105 comprises a chemically treated reinforced cellulose based fibrous material available under the trade name CMC from Weyerhaeuser Co., USA. In another preferred embodiment, the capture / distribution layer 105 comprises a conventional cellulose based fluff material, also known as wood pulp fiber, available under the trade name FLINT RIVER from Weihaihauser Co., USA. Include.

The present invention is, of course, applicable to other absorbent products known under other names, such as incontinence briefs, adult incontinence products, training pants, diaper inserts, cosmetic tissues, paper towels and the like.

Test Methods

a. General principles

All tests are performed at about 23 ± 2 ° C. and relative humidity about 50 ± 10%.

Unless explicitly stated, the particular synthetic urine used in the test method is commonly known as JAYCO SYNURINE, available from Jayco Pharmaceuticals Company (Camp Hill, PA). Do. Compounding of the synthetic urine is _{KCl 20g / ℓ, Na 2 SO} 4 2.0g / ℓ, (NH 4) H 2 PO 4 0.85gℓ, (NH 4) HPO 4 0.15g / ℓ, CaCl 2 0.19g / ℓ and MgCl ₂ 0.23 g / l. All chemicals are reagent grade. The pH of synthetic urine is about 6.0 to 6.4.

b. Take test of final product

Referring to FIG. 4, 75 ml of synthetic urine eluate was pumped at a rate of 15 ml / sec using a pump (Model 7520-00, supplied by Cole Parmer Instruments, Chicago, USA) 5 cm above the sample surface. Add to The time at which urine is absorbed is recorded by a timer. The ejection is repeated every 5 minutes with an interval of exactly 5 minutes until the jet is sufficiently added to the product. Current test data is obtained by adding in four forms.

A test sample comprising an absorbent core and comprising a topsheet and a backsheet is arranged to lie flat on the foam platform 11 in a Perspex box (only its base 12 is shown). . A perspex plate 13 having an opening of 5 cm diameter in the middle is placed on top of the sample. Synthetic urine is introduced into the sample through a cylinder 14 fixed to the opening and glued. The electrode 15 is positioned on the bottom surface of the plate in contact with the surface of the absorbent structure 10. Connect the electrode to the timer. A load 16 is applied to the top of the plate to simulate the weight of the baby, for example. A pressure of 50 g / cm 2 is typically used for this test.

As the test liquid is introduced into the cylinder, the test liquid is typically stacked on top of the absorbent structure to complete the electrical circuit between the electrodes. This causes the timer to start running. The timer stops when the absorbent structure absorbs the urine jet and the electrical connection between the electrodes is broken.

The capture rate is defined as the volume of jet absorbed per unit time (in milliseconds). Capture rate is calculated for each jet introduced into the sample. Of particular importance in the present invention are the first and last of four bursts.

This test is primarily designed to evaluate products having an absorption capacity of about 300 ml to about 400 ml. If products with significantly different capacities have to be evaluated, in particular the setting of the fluid volume for the ejections should be adjusted to approximately 20% of the theoretical volume and the deviation should be recorded.

c. Wetting test of the final product

The disposable absorbent product is placed in the machine described in FIG. 4 as described in the capture test of the final product described above, except as follows. 225 ml of synthetic urine is added to the absorbent product sample. The addition is carried out by three jets of 75 ml each time every three minutes. No additional pressure is applied except for the negligible pressure that can result from the perspex plate.

After the addition of 225 ml of synthetic urine is complete, the perspex plate is removed. Two pieces of filter paper (ERT FF3.W / S, supplied by Hollingsworth & Vose, UK) having dimensions of 12 cm x 12 cm are weighed and placed on urine-impregnated diapers. A load of 2 kg was applied to the filter paper over an area of 10 cm × 10 cm for 2 minutes (ie 0.28 psi). Remove the filter paper and reweigh. Diaper rewet is defined as the weight (g) of increased filter paper.

d. In Bag Stack Height

In essence, the in bag stack height is measured by measuring the height of a pile of absorbent products packaged in a box or bag as supplied to the market, and dividing the height by the number of products in the pile.

The in bag stack height can be measured by taking one bag and making a measurement or by simulating the pressure of the packaging bag in a suitable device (eg, a stress-strain measuring device such as that provided by an INSTRON device). can do.

This test was conducted mainly on 'folded' products, ie products that were folded only once in the transverse direction of the product near the middle of the product such that the front and rear portions of the product overlap in the bag. For products that are grounded or folded in three (three layered products), the results need to be corrected accordingly.

e. Basic weight

Base weights are often mentioned for various materials. The basis weight can be obtained by essentially dividing the weight of the specimen by its area. The size of the area and the number of rewired replicates depends on the homogeneity of the specimen.

f. Hydrophilic / hydrophobic

Hydrophilicity (and therefore wettability) is typically defined by the contact angle and surface tension of the liquid and solids involved. This is discussed in detail in R. F. Gould, 'Contact Angle, Wettability and Adhesion', American Chemical Society publication, Copyright (1964). In the present invention, the material can be divided into three groups as follows.

Materials that are 'very hydrophilic' (abbreviated 'h +'): they generally have a contact angle of less than about 80 degrees. Examples are cellulosic fibers and olefinic polymers that have been treated with effective and strong surfactants (at least when first exposed to wetting).

Substantially hydrophobic substances (abbreviated 'h-'): They generally have contact angles greater than about 100 degrees. Examples are pure olefins (polyethylene / polypropylene) free of surfactants (no surface and no incorporated resin).

'Moderately hydrophilic' materials (abbreviated 'ho'): they have a contact angle of about 90 degrees. Examples include polypropylene / polyethylene with less effective resin incorporating surfactants and other materials with less hydrophilic surfactants applied to the surface of olefins.

The following examples describe and demonstrate preferred embodiments that fall within the scope of the invention. These examples are provided for illustrative purposes only and should not be construed as limiting the invention as many variations may be made without departing from the spirit and scope of the invention.

Example 1

This example shows a method of making HFAP for use in the present invention.

About 5 mm by stirring together with 2.0 parts of sodium persulfate and 0.08 parts of 1-ascorbic acid, an aqueous solution of 37% acrylic monomer consisting of 74.95 mol% of sodium acrylate, 25 mol% of acrylic acid and 0.05 mol% of trimethylolpropane triacrylate The finely divided gel hydrated polymer is produced by the particle size of. The gel hydrated polymer is dried with a hot air dryer at 150 ° C., pulverized with a hammery fine powder, sieved through a 20 mesh metal network to separate the powder passing through the 20 mesh as an absorbent polymer A (average particle size about 350 microns). .

100 parts of absorbent polymer A are mixed with 0.5 parts of glycerol, 2 parts of water and 2 parts of ethyl alcohol, and the resulting mixture is heat treated at 210 ° C. to obtain a absorbent polymer B whose surface area is secondarily crosslinked.

Example 2

This example shows a method of preparing the A-HFAP of the present invention.

10 g of benzalkonium chloride (available from Wako Chemical, Osaka, Japan) is dissolved in 100 ml of distilled ionized water. After complete dissolution, the solution is introduced into the air tank to which the spray nozzle and air pump are connected. 500 g of the absorbent polymer B of Example 1 is evenly placed on a stainless steel plate to form a thin layer of about 3 mm thickness. 25 g of aqueous benzalkonium chloride solution is sprayed onto 500 g of absorbent polymer B at room temperature. The particles are then placed in a food mixer and stirred for 15 minutes. The benzalkonium chloride-coated absorbent polymer B particles are then dried in a dynamic oven at 95 ° C. for 1 hour or by hot air drying for 10 minutes to reduce the moisture content to less than 1% of the absorbent polymer B particles. The dry particles were pulverized lightly into granules of size 800 μm or less, resulting in the polymer powder as planned. The resulting particles contain 0.5% benzalkonium chloride.

Example 3

This example shows a method of making another embodiment of the A-HFAP of the invention.

In this case, the absorbent polymer B was replaced with Aqualic CA-L76 (crosslinked sodium polyacrylate; available from Nippon Shokubai Co. Ltd., Osaka, Japan). Except for the same procedure as in Example 2. This method produced polymer powder as planned after coating with benzoalkonium chloride.

Example 4

This example shows an absorbent core comprising the A-HFAP of the present invention for use in disposable absorbent articles.

Southern Pine wood pulp is decomposed and opened in the airflow chamber. A fiber of average length of about 3 mm is dropped on the vacuum plate. While laying down the fiber, the A-HFAP of Example 3 is sprayed onto the wood pulp fibers. A core is formed containing wood pulp fibers 230-400 g / m 2 and A-HFAP 160-360 g / m 2. The core is suitable for use in infant and / or adult incontinence diaper applications. Typical compositions for use in baby diapers of size L are as follows:

Example 5

This example shows a disposable baby diaper comprising A-HFAP of the present invention.

The dimensions described are for diapers for use with children of 6 to 10 kg. These dimensions may be proportionally modified for different size child or adult incontinence briefs according to standard practice.

1. Backsheet: 0.020-0.038 mm fluid impermeable film made according to US Pat. No. 4,687,478; 33 cm wide at the top and bottom; 28.5 cm inward from the sides to the width of the center; 50.2 cm in length.

2. Topsheet: Carded and heat bonded staple length polypropylene fibers (Hercules 151 polypropylene); 33 cm wide at the top and bottom; 28.5 cm inward from the sides to the width of the center; 50.2 cm in length.

3. Absorbent core: 28.6 g of cellulose wood pulp and 4.9 g of A-HFAP of Example 3; Thickness 8.4 mm (calendered); 28.6 cm wide at the top and bottom; 10.2 cm inward from the sides to the width of the center; 44.5 cm in length.

4. Elastic leg bands: four individual rubber strips (two per side); Width 4.77 mm; Length 4.77 mm; 0.178 mm thick (all of the above dimensions are in the relaxed state).

The diaper is prepared in a standard manner by placing the core material on the backsheet, covering it with the topsheet, and bonding.

Stretch the elastic band (called 'inner' and 'outer', depending on the position nearest or farthest from the core) to about 50.2 cm and top / back along each longitudinal side of the core (two bands per side). It is located between sheets. The inner band along each side is located about 55 mm from the narrowest width of the core (measured from the inner edge of the elastic band). This provides a spacing element along both sides of the diaper comprising a flexible topsheet / backsheet material between the inner elastic band of the core and the bent edge. The inner band is bonded along the length of the stretched state. The topsheet / backsheet assembly is flexible and the bonded bands contract to elasticize the sides of the diaper.

The resulting diaper combines fluid adsorption and antibacterial properties.

Example 6

This example shows an adult incontinence product comprising the A-HFAP of the present invention.

According to the manufacturing process of Example 4, a heavy core having 24 to 40 g of wood pulp fibers and 10 to 20 g of A-HFAP is formed. The core is then placed between the fluid impermeable multiple backsheet and the fluid permeable topsheet to form an adult incontinence product.

Example 7

This example shows a lightweight pantyliner product comprising the A-HFAP of the present invention.

Lightweight pantyliners suitable for use between menstrual periods include pads. The pad has a surface area of 117 cm 2 and contains 3 g of wood pulp fibers and 1.5 g of A-HFAP from Example 3. The pad is then placed between the porous molded film topsheet according to US Pat. No. 4,463,045 and the fluid impermeable backsheet prepared according to US Pat. No. 4,687,478 to form a lightweight pantyliner product. The resulting pantiliner combines fluid adsorption and antibacterial properties.

Example 8

This example shows a menstrual pad comprising A-HFAP of the present invention.

According to the design of U.S. Patent No. 4,687,478, issued to Aug. Tiltberg on August 18, 1987, a sanitary napkin in the form of a sanitary napkin has two flaps extending outward from the absorbent core. However, the pad used had a surface area of 117 cm 2 and contained 6-12 g of wood pulp fibers and 1-3 g of A-HFAP of Example 2. Fluid permeable topsheets are prepared according to US Pat. No. 4,463,045. Fluid impermeable backsheets are prepared according to US Pat. No. 4,687,478. The resulting menstrual pad combines fluid adsorption and antibacterial properties.

Aspects and embodiments of the invention described herein have many surprising advantages, including improved efficacy and improved processability. For example, by coating the surface area of the HFAP with an antimicrobial agent rather than incorporating the antimicrobial agent into the HFAP, the antimicrobial agent will act upon entry of the fluid into the absorbent core. In contrast, when an antimicrobial agent is incorporated into HFAP, its efficacy will be delayed until the HFAP begins to swell by the fluid.

In addition, by coating HFAP with an antibacterial agent, for example, the release of HFAP dust particles into the air is reduced. This reduction in HFAP dust particles provides a safer environment for the operator, less downtime spent on the cleaning process, and loss of material.

All publications, patent applications, and issued patents mentioned above are hereby incorporated by reference in their entirety.

The examples and embodiments described herein are provided for illustrative purposes only and those skilled in the art will recognize that various modifications or variations are possible in this regard and are included within the spirit and scope of the invention and the scope of the appended claims.

Claims (10)

a) a hydrogel-forming absorbent polymer, and b) an antibacterial agent that is benzalkonium chloride or chlorhexidine, An antimicrobial hydrogel forming absorbent polymer, wherein the hydrogel forming absorbent polymer is coated with an antimicrobial agent after surface crosslinking treatment. delete delete The method of claim 1, An antimicrobial hydrogel-forming absorbent polymer having a ratio of polymer to antibacterial agent of 100: 0.01 to 100: 2. Performing a surface crosslinking treatment of the hydrogel forming absorbent polymer; And Coating the hydrogel forming absorbent polymer with an antimicrobial agent that is benzalkonium chloride or chlorhexidine A method for producing an antibacterial hydrogel-forming absorbent polymer comprising a. delete delete Backsheet; Upper sheet; And Absorbent core comprising the antimicrobial hydrogel-forming absorbent polymer according to claim 1 Disposable absorbent product comprising a. The method of claim 8, Disposable absorbent products that are disposable diapers. delete