Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/53—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium
  • A61F13/531—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium having a homogeneous composition through the thickness of the pad
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
  • A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
  • A61L15/42—Use of materials characterised by their function or physical properties
  • A61L15/60—Liquid-swellable gel-forming materials, e.g. super-absorbents
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
  • A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
  • A61L15/42—Use of materials characterised by their function or physical properties

Definitions

• the invention is related to absorbent personal care products. More particularly, it concerns absorbent disposable articles such as feminine care napkins, diapers and training pants, wound care dressings and bandages, and adult incontinence products, that are highly conformable to the body of the wearer.
• top sheet material also referred to as a cover sheet or liner
• absorbent core and a liquid impervious back sheet.
• Some may also have a surge layer or other specialized layers between the top sheet and absorbent core.
• Such materials can be somewhat stiff and uncomfortable.
• the layers of these products are usually made from polymer fibers and films, and the absorbent core layer is usually made from wood pulp and superabsorbent particles that swell when wetted.
• the absorbent core layer is usually made from wood pulp and superabsorbent particles that swell when wetted.
• such structures often do not allow fluid movement throughout, thus filling or overfilling the portion of the product in the area where an insult is typically delivered.
• Attempts have been made to address the movement of fluid in personal care products, again with the use of polymer fibers and the like.
• a personal care product which is comprised of an absorbent, preferably superabsorbent, and more preferably superabsorbent fibers, and water-soluble polymer.
• an absorbent preferably superabsorbent, and more preferably superabsorbent fibers, and water-soluble polymer.
• nonwoven fabric or web means a web having a structure of individual fibers or threads which are interlaid, but not in an identifiable manner as in a knitted fabric.
• Nonwoven fabrics or webs have been formed from many processes such as for example, meltblowing processes, spunbonding processes, and bonded carded web processes.
• the basis weight of nonwoven fabrics is usually expressed in ounces of material per square yard (osy) or grams per square meter (gsm) and the fiber diameters useful are usually expressed in microns. (Note that to convert from osy to gsm, multiply osy by 33.91).
• spunbonded fibers refers to small diameter fibers that are formed by extruding molten thermoplastic material as filaments from a plurality of fine capillaries of a spinneret. Such a process is disclosed in, for example, US Patent 4,340,563 to Appel et al.
• the fibers may also have shapes such as those described, for example, in US Patents 5,277,976 to Hogle et al. which describes fibers with unconventional shapes.
• Airlaying is a well-known process by which a fibrous nonwoven layer can be formed.
• bundles of small fibers having typical lengths ranging from about 3 to about 52 millimeters (mm) are separated and entrained in an air supply and then deposited onto a forming screen, usually with the assistance of a vacuum supply..
• the randomly deposited fibers then are bonded to one another using, for example, hot air or a spray adhesive.
• Airlaying is taught in, for example, US Patent 4,640,810 to Laursen et al.
• coform means a process in which at least one meltblown diehead is arranged near a chute through which other materials are added to the web while it is forming.
• Such other materials may be pulp, superabsorbent particles, natural polymers (for example, rayon or cotton fibers) and/or synthetic polymers (for example, polypropylene or polyester) fibers, for example, where the fibers may be of staple length.
• Coform processes are shown in commonly assigned US Patents 4,818,464 to Lau and 4,100,324 to Anderson et al. Webs produced by the coform process are generally referred to as coform materials.
• “Bonded carded web” refers webs are made from staple fibers which are sent through a combing or carding unit, which breaks apart and aligns the staple fibers in the machine direction to form a generally machine direction-oriented fibrous nonwoven web. Such fibers are are usually purchased in bales which are placed in a picker which separates the fibers prior to the carding unit. Once the web is formed, it then is bonded by one or more of several known bonding methods. One such bonding method is powder bonding, wherein a powdered adhesive is distributed through the web and then activated, usually by heating the web and adhesive with hot air.
• Another suitable bonding method is pattern bonding, wherein heated calender rolls or ultrasonic bonding equipment are used to bond the fibers together, usually in a localized bond pattern, though the web can be bonded across its entire surface if so desired.
• Another suitable and well-known bonding method, particularly when using bicomponent staple fibers, is through-air bonding.
• gel means a fluid in which dispersed and continuous phases have mixed to a sufficient degree to produce a viscous or visco-elastic, jelly-like product.
• personal care product means bandages and wound care items, diapers, training pants, swimwear, absorbent underpants, adult incontinence products, and feminine hygiene products.
• the artificial menses fluid used in the testing was made according to US Patent
• the plasma is separated and stored separately, the buffy coat removed and discarded and the packed red blood cells stored separately as well.
• the blood must be treated in some manner so that it may be processed without coagulating. Various methods are known to those skilled in the art, such as defibrinating the blood to remove the clotting fibrous materials, the addition or anti-coagulant chemicals and others.
• the blood must be non-coagulating in order to be useful and any method that accomplishes this without damaging the plasma and red cells is acceptable.
• Jumbo chicken eggs are separated, the yolk and chalazae discarded and the egg white retained.
• the egg white is separated into thick and thin portions by straining the white through a 1000-micron nylon mesh for about 3 minutes, and the thinner portion discarded.
• the thick portion of egg white, which is retained on the mesh is collected and drawn into a 60 cc syringe, which is then placed on a programmable syringe pump and homogenized by expelling and refilling the contents five times.
• the amount of homogenization is controlled by the syringe pump rate of about 100 ml/min, and the tubing inside diameter of about 0.12 inches.
• After homogenizing the thick egg white has a viscosity of about 20 centipoise at 150 sec "1 and is then placed in the centrifuge and spun to remove debris and air bubbles at about 3000 rpm for about 10 minutes
• the thick, homogenized egg white which contains ovamucin, is added to a 300 cc FENWAL® Transfer pack container using a syringe. Then 60 cc of the swine plasma is added to the FENWAL® Transfer pack container.
• the FENWAL® Transfer pack container is clamped, all air bubbles removed, and placed in a Stomacher lab blender where it is blended at normal (or medium) speed for about 2 minutes.
• the FENWAL® transfer pack container is then removed from the blender, 60 cc of swine red blood cells are added, and the contents mixed by hand kneading for about 2 minutes or until the contents appeared homogenous.
• a hematocrit of the final mixture should show a red blood cell content of about 30 weight percent and generally should be at least within a range of 28-32 weight percent for artificial menses made according to this Example.
• the amount of egg white is about 40 weight percent.
• FENWAL® Transfer pack container 300 ml, with coupler, code 4R2014: Baxter HealthCare Corporation, Fenwal Division, Deerfield, IL 60015.
• Hemata Stat-ll device to measure hemocrits serial no. 1194Z03127: Separation Technology, Inc., 1096 Rainer Drive, Altamont Springs, FL 32714.
• Typical personal care product structures include a top sheet, absorbent core and impervious backsheet and, optionally, a surge layer between the top sheet and absorbent core.
• the top sheet material is the layer against the wearer's skin and so the first layer in contact with liquid or other exudate from the wearer.
• the top sheet further serves to isolate the wearer's skin from the liquids held in an absorbent structure and should be compliant, soft feeling and non-irritating.
• Various materials can be used in forming the bodyside top sheet of the present invention, including apertured plastic films, woven fabrics, nonwoven webs, foams and the like.
• An optional surge layer may be interposed between and in intimate, liquid communicating contact with the top sheet and another layer.
• Various foams and woven and nonwoven webs are used to construct a surge layer, and there may be a number of surge layers of different fiber size, basis weight, etc.
• Exemplary surge materials may be found in US Patent numbers 5,879,343 and 5,820,973 to Dodge et al.
• the retention or absorbent core layer is usually made from wood pulp and/or superabsorbent particles.
• Pulps include standard soft-wood fluffing grade such as CR- 1654 from US Alliance Pulp Mills, Coosa, Alabama, and high bulk additive formaldehyde free pulp (HBAFF) available from the Weyerhaeuser Corporation of Tacoma, WA.
• HBAFF formaldehyde free pulp
• Another useful pulp is a chemically cross-linked pulp fiber such as Weyerhaeuser NHB- 416.
• Useful particulate superabsorbents are available from the Dow Chemical Company of Midland Ml, and the Stockhausen Company of Greensboro, NC 27406 (e.g., FAVOR® 870 superabsorbent) as well as others.
• the backsheet is sometimes referred to as the outer cover and is the farthest layer from the wearer.
• the outer cover is typically formed of a thin thermoplastic film, such as polyethylene film, which is substantially impermeable to liquid.
• the outer cover functions to prevent body exudates contained in an absorbent structure from wetting or soiling the wearer's clothing, bedding, or other materials contacting the diaper.
• the outer cover may be, for example, a polyethylene film having an initial thickness of from about 0.5 mil (0.012 millimeter) to about 5.0 mil (0.12 millimeter).
• the polymer film outer cover may be embossed and/or matte finished to provide a more aesthetically pleasing appearance.
• the outer cover may optionally be composed of a vapor or gas permeable, microporous "breathable" material, that is permeable to vapors or gas yet substantially impermeable to liquid.
• a vapor or gas permeable, microporous "breathable" material that is permeable to vapors or gas yet substantially impermeable to liquid.
• the personal care product of the invention includes water-soluble materials and absorbent materials. When wetted and after the application of minimal force, this material becomes gelatinous and can conform to the shape of the wearer by flowing under load. This flowing can also serve to distribute the absorbed fluid throughout the structure.
• the absorbent materials may include wood pulp fibers and superabsorbent and blends thereof. Wood pulps include standard softwood fluffing grade such as CR-1654 (US Alliance Pulp Mills, Coosa, Alabama).
• Pulp may be modified in order to enhance the inherent characteristics of the fibers and their processability.
• Curl may be imparted to the fibers by methods including chemical treatment or mechanical twisting. Curl is typically imparted before crosslinking or stiffening. Pulps may be stiffened by the use of crosslinking agents such as formaldehyde or its derivatives, glutaraldehyde, epichlorohydrin, methylolated compounds such as urea or urea derivatives, dialdehydes such as maleic anhydride, non-methylolated urea derivatives, citric acid or other polycarboxylic acids. Some of these agents are less preferable than others due to environmental and health concerns.
• Pulp may also be stiffened by the use of heat or caustic treatments such as mercerization.
• these types of fibers include NHB416 which is a chemically crosslinked southern softwood pulp fibers which enhances wet modulus, available from the Weyerhaeuser Corporation of Tacoma, WA.
• Other useful pulps are debonded pulp (NF405) and non-debonded pulp (NB416) also from Weyerhaeuser.
• HPZ3 from Buckeye Technologies, Inc of Memphis, TN has a chemical treatment that sets in a curl and twist, in addition to imparting added dry and wet stiffness and resilience to the fiber.
• Another suitable pulp is Buckeye HP2 pulp and still another is IP Supersoft from International Paper Corporation.
• Suitable rayon fibers are 1.5 denier Merge 18453 fibers from Acordis Cellulose Fibers Incorporated of Axis, Alabama.
• Superabsorbents that are useful in the present inventions can be chosen from classes based on chemical structure as well as physical form. These include superabsorbents with low gel strength, high gel strength, surface cross-linked superabsorbents, uniformly cross-linked superabsorbents, or superabsorbents with varied cross-link density throughout the structure. Superabsorbents may be based on chemistries that include but are not limited to acrylic acid, iso-butylene/maleic anhydride, polyethylene oxide, carboxy-methyl cellulose, poly vinyl pyrrollidone, and poly vinyl alcohol.
• the superabsorbents may range in rate from slow to fast.
• the superabsorbents may be in the form of foams, macroporous or microporous particles or fibers, may have fuzzy or fibrous coatings or morphology.
• the superabsorbents may be in the shape of ribbons, particles, fibers, sheets or films.
• Superabsorbents may be in various length and diameter sizes and distributions.
• the superabsorbents may be in various degrees of neutralization. Neutralization occurs through use of counter ions such as Li, Na, K, Ca.
• An Example of these superabsorbents may be obtained from the Stockhausen Company (of Greensboro, NC) and is designated as FAVOR® 880.
• Fibrous superabsorbents include superabsorbents obtained from Camelot
• Superabsorbents Inc. (of Charlotte, NC) are designated as FIBERDRI® 1241 and FIBERDRI® 1161.
• Fibrous superabsorbents also include FIBERSORB®, which is a 100 percent fibrous superabsorbent (formerly available from the Arco Chemical Company of Newtown Square, PA). Single or common fibers produced from a mixture of superabsorbent and water soluble polymers are available as ABSORVATE® superabsorbent (from BFF Nonwovens of Somerset, UK).
• a water-soluble polymer includes a water-soluble poly(vinyl alcohol) copolymer named Ecomaty AX10000 and manufactured by Nippon-Gohsei of Osaka, Japan.
• the meltflow rate of this AX10000 copolymer was 100 grams per 10 minutes at a temperature of 190 C under 2.16 kilograms load using ASTM Test Method D-1238.
• This polymer may be made into fibers in known fiber producing processes such as meltblowing.
• Another water-soluble polymer is a polyamide polymer with the code number NP 2068 and available from the H.B. Fuller Company of St. Paul, Minnesota. The viscosity of the NP 2068 polymer was 95 Pascal-seconds at a temperature of 204°C. Another such polyamide polymer is available under the code number NP 2074 from H.B. Fuller. These polymers may also be made into fibers in known fiber producing processes such as meltblowing.
• PLA polylactic acid
• BAU a blend of BIONOLLE®, adipic acid and UNITHOX®
• PLA is not a blend but a pure polymer like polypropylene.
• BAU represents a blend of BIONOLLE®, adipic acid, and UNITHOX® at different percentages.
• the blend for staple fiber is 44.1 percent BIONOLLE® 1020, 44.1 percent BIONOLLE® 3020, 9.8 percent adipic acid and 2 percent UNITHOX® 480, though spunbond BAU fibers typically use about 15 percent adipic acid.
• BIONOLLE® 1020 is polybutylene succinate
• BIONOLLE® 3020 is polybutylene succinate adipate copolymer
• UNITHOX® 480 is an ethoxylated alcohol.
• BIONOLLE® is a trademark of Showa Highpolymer Co. of Japan.
• UNITHOX® is a trademark of Baker Petrolite which is a subsidiary of Baker Hughes International.
• the web of water-soluble polymer and superabsorbent for use in the instant invention may be made by a number of different processes, limited only by the idiosyncratic constraints imposed by a particular polymer.
• Polyvinyl alcohol (PVOH) for example, may be successfully fiberized according to the meltblowing process and pulp or superabsorbent particles or fibers may be admixed with it according to the coform process.
• Superabsorbent/water-soluble polymer mixtures such as ABSORVATE® material, for example, may be processed by meltblowing and solution spinning as well.
• superabsorbent and water-soluble polymers may be meltblown in separate banks of a typical meltblowing operation to produce a mixed fiber fabric in one processing step.
• the polymers may be separately fiberized and subsequently mixed in a desired ratio by various known processes such as bonding and carding, airlaying, etc.
• the superabsorbent fibers may be made into a web and a liquid, water soluble polymer introduced to the web as an adhesive to give structural integrity to the web.
• the adhesive polymers include polyvinyl alcohol, polyethylene oxide and polyvinyl pyrollidone and they may be added to the web by spraying, dipping and any other suitable method known in the art.
• the gel properties of the blend of water-soluble and superabsorbent fibers may be controlled by controlling the ratio of the fibers, the molecular weight and other properties of the polymers chosen, as well as the fabric properties such as basis weight, bonding pattern if any, fabric density and the like.
• a successful blend will flow as a gel after being wetted and after the application of minimal force, but will not be so liquid as to escape from the personal care product. Careful product design and a reasonable amount of experimentation will allow one skilled in the art to develop the proper blend for his application. The inventor believes that the most efficacious blends will be found within the range of between 20 and 80 weight percent water-soluble polymer and 80 and 20 weight percent superabsorbent fiber to produce a gel after wetting.
• Example 70 percent water soluble polymer to 70 percent superabsorbent fiber and still more particularly from 60 percent water soluble polymer to 60 percent superabsorbent fiber, with the balance being the other component, are believed to be desirable. Additional components, such as surfactants, skin wellness additives, odor control additives, colorants and the like may also be present in a minor amount.
• a thermally point bonded carded web designated NCF200, commercially available from BFF Nonwovens (Somerset, England, UK) was saturated with an artificial menses solution prepared according to the method above.
• This web was made from fibers composed of superabsorbent and water-soluble polyvinyl alcohol in a common (i.e., the same) fiber and had a basis weight of about 200 gsm.
• the web was allowed to absorb the solution and then rolled with a glass mixing rod. Upon the application of the force from the rolled rod, the web became a gel.

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• Health & Medical Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Engineering & Computer Science (AREA)
• Epidemiology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Materials Engineering (AREA)
• Hematology (AREA)
• Dispersion Chemistry (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• Vascular Medicine (AREA)
• Orthopedics, Nursing, And Contraception (AREA)
• Absorbent Articles And Supports Therefor (AREA)
• Cosmetics (AREA)
• Nonwoven Fabrics (AREA)

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• 2001
  • 2001-08-29 KR KR10-2003-7002997A patent/KR20030029886A/ko not_active Withdrawn
  • 2001-08-29 WO PCT/US2001/027076 patent/WO2002017982A2/en not_active Ceased
  • 2001-08-29 EP EP01968313A patent/EP1315529A2/de not_active Withdrawn
  • 2001-08-29 CN CN01814871A patent/CN1449296A/zh active Pending
  • 2001-08-29 MX MXPA03001103A patent/MXPA03001103A/es unknown
  • 2001-08-29 BR BR0113151-6A patent/BR0113151A/pt not_active IP Right Cessation
  • 2001-08-29 JP JP2002522953A patent/JP2004507323A/ja active Pending
  • 2001-08-29 AU AU2001288568A patent/AU2001288568A1/en not_active Abandoned
  • 2001-08-30 AR ARP010104148A patent/AR033835A1/es not_active Application Discontinuation
• 2003
  • 2003-01-24 ZA ZA200300677A patent/ZA200300677B/en unknown

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