WO2000000136A1 - Element de transport de liquides pourvu de zones centrales a permeabilite elevee et de zones d'orifice a pression de seuil elevee - Google Patents

Element de transport de liquides pourvu de zones centrales a permeabilite elevee et de zones d'orifice a pression de seuil elevee Download PDF

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Publication number
WO2000000136A1
WO2000000136A1 PCT/US1999/014633 US9914633W WO0000136A1 WO 2000000136 A1 WO2000000136 A1 WO 2000000136A1 US 9914633 W US9914633 W US 9914633W WO 0000136 A1 WO0000136 A1 WO 0000136A1
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WO
WIPO (PCT)
Prior art keywords
liquid
region
liquid transport
transport member
port
Prior art date
Application number
PCT/US1999/014633
Other languages
English (en)
Inventor
Bruno Johannes Ehrnsperger
Mattias Schmidt
Fred Naval Desai
Gary Dean Lavon
Gerald Alfred Young
Karl Michael Schumann
Donald Carroll Roe
Original Assignee
The Procter & Gamble Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by The Procter & Gamble Company filed Critical The Procter & Gamble Company
Priority to AU48406/99A priority Critical patent/AU4840699A/en
Priority to CA002336022A priority patent/CA2336022A1/fr
Priority to EP99932008A priority patent/EP1091712A1/fr
Priority to JP2000556722A priority patent/JP2002522250A/ja
Publication of WO2000000136A1 publication Critical patent/WO2000000136A1/fr

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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
    • A61F13/534—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 an inhomogeneous composition through the thickness of the pad
    • A61F13/537—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 an inhomogeneous composition through the thickness of the pad characterised by a layer facilitating or inhibiting flow in one direction or plane, e.g. a wicking layer
    • A61F13/5376—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 an inhomogeneous composition through the thickness of the pad characterised by a layer facilitating or inhibiting flow in one direction or plane, e.g. a wicking layer characterised by the performance of the layer, e.g. acquisition rate, distribution time, transfer time
    • 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
    • A61F13/15203—Properties of the article, e.g. stiffness or absorbency
    • 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
    • A61F13/36—Surgical swabs, e.g. for absorbency or packing body cavities during surgery
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
    • B01D17/02—Separation of non-miscible liquids
    • B01D17/0202—Separation of non-miscible liquids by ab- or adsorption
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
    • B01D17/08—Thickening liquid suspensions by filtration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
    • B01D17/08—Thickening liquid suspensions by filtration
    • B01D17/085—Thickening liquid suspensions by filtration with membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
    • B65D47/00—Closures with filling and discharging, or with discharging, devices
    • B65D47/04—Closures with discharging devices other than pumps
    • B65D47/20—Closures with discharging devices other than pumps comprising hand-operated members for controlling discharge
    • B65D47/2018—Closures with discharging devices other than pumps comprising hand-operated members for controlling discharge comprising a valve or like element which is opened or closed by deformation of the container or closure
    • B65D47/2031—Closures with discharging devices other than pumps comprising hand-operated members for controlling discharge comprising a valve or like element which is opened or closed by deformation of the container or closure the element being formed by a slit, narrow opening or constrictable spout, the size of the outlet passage being able to be varied by increasing or decreasing the pressure
    • 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
    • A61F13/15203—Properties of the article, e.g. stiffness or absorbency
    • A61F2013/15284—Properties of the article, e.g. stiffness or absorbency characterized by quantifiable properties
    • A61F2013/15365—Dimensions
    • A61F2013/1539—Dimensions being expandable
    • 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
    • A61F13/15203—Properties of the article, e.g. stiffness or absorbency
    • A61F2013/15284—Properties of the article, e.g. stiffness or absorbency characterized by quantifiable properties
    • A61F2013/15487—Capillary properties, e.g. wicking
    • A61F2013/15495—Capillary properties, e.g. wicking pore dimension
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/40—Devices for separating or removing fatty or oily substances or similar floating material
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/32—Hydrocarbons, e.g. oil

Definitions

  • the present invention relates to liquid transport members useful for a wide range of applications requiring high flow and/or flux rate, wherein the liquid can be transported through such a member, and/ or be transported into or out of such 20 a member.
  • Such members are suitable for many applications, as - without being limited to - disposable hygiene articles, water irrigation systems, spill absorbers, oil/water separators and the like.
  • the invention further relates to liquid transport systems comprising said liquid transport members and articles utilizing these.
  • the transport will happen from a liquid source through a liquid transport member to a liquid sink, for example from a reservoir through a pipe to
  • liquid transport elements or members can be found in fields like water irrigation such as desc ⁇ bed in EP-A-0.439.890, or in the hygiene field, such as for absorbent articles like baby diapers both of the pull-on type or with fastening elements like tapes, training pants, adult incontinence products, feminine protection devices.
  • capillary flow members such as fibrous materials like blotting paper, wherein the liquid can wick against the gravity.
  • fibrous materials like blotting paper
  • Such materials are limited in their flow and/or flux rates, especially when wicking height is added as an additional requirement.
  • An improvement particularly towards high flux rates at wicking heights particularly useful for example for application in absorbent articles has been described in EP-A-0.810.078.
  • capillary flow members can be non-fibrous, but yet porous structures, such as open celled foams.
  • hydrophilic polymeric foams have been described, and especially hydrophilic open celled foams made by the so called High Internal Phase Emulsion (HIPE) polymerization process have been described in US-A-5.563.179 and US-A- 5.387.207.
  • HIPE High Internal Phase Emulsion
  • liquid transport members that can transport liquid against gravity at very high flux rates.
  • liquid is not homogeneous in composition (such as a solution of salt in water), or in its phases (such as a liquid/solid suspension), it can be desired to transport the liquid in its totality, or only parts thereof.
  • composition such as a solution of salt in water
  • phases such as a liquid/solid suspension
  • filtration technology exploits the higher and lower permeability of a member for one material or phase compared to another material or phase.
  • There is abundance of art in this field in particular also relating to the so called micro-, ultra-, or nano-filtration.
  • Some of the more recent publications are: US-A-5.733.581 relating to melt-blown fibrous filter; US-A-5.728.292 relates to non-woven fuel filter; WO-A- 97/47375 relating to membrane filter systems; WO-A- 97/35656 relating to membrane filter systems;
  • EP-A-0.780.148 relating to monolithic membrane structures
  • EP-A-0.773.058 relating to oleophilic filter structures.
  • Such membranes are also disclosed to be used in absorbent systems.
  • US-A-4.820.293 Korean absorbent bodies are disclosed, for being used in compresses, or bandages, having a fluid absorbent substance enclosed in a jacket made of one essentially homogeneous material. Fluid can enter the body through any part of the jacket, and no means is foreseen for liquid to leave the body.
  • fluid absorbent materials can have osmotic effects, or can be gel- forming absorbent substances enclosed in semipermeable membranes, such as cellulose, regenerated cellulose, cellulose nitrate, cellulose acetate, cellulose acetate butyrate, polycarbonate, polyamide, fiberglass, polysulfone, of polytetrafluoroethylene, having pore sizes of between 0.001 ⁇ m and 20 ⁇ m, preferably between 0.005 ⁇ m and 8 ⁇ m, especially about 0.01 ⁇ m.
  • the permeability of the membrane is intended to be such that the absorbed liquid can penetrate, but such that the absorbent material is retained.
  • membranes having a high permeability k and a low thickness d so as to achieve a high liquid conductivity k/d of the layer, as being described herein after.
  • promoters with higher molecular weight e.g., polyvinyl pyrrolidone with a molecular weight of 40,000
  • the maximum pore size stated therein to be useful for this application is less than 0.5 ⁇ m, with pore sizes of about 0.01 ⁇ m or less being preferred.
  • the exemplified materials allow the calculation of k/d values in the range of 3 to 7 * 10 "14 m.
  • the absorbent body can further comprise for rapid discharge of fluids a liquid acquisition means, such as conventional acquisition means to provide interim storage of the fluids before these are slowly absorbed.
  • a liquid acquisition means such as conventional acquisition means to provide interim storage of the fluids before these are slowly absorbed.
  • US-A-5.082.723 discloses an osmotic material like NaCl which is enclosed by superabsorbent material, such as a copolymer of acrylic acid and sodium acrylate, thereby aiming at improving absorbency, such as enhanced absorptive capacity on a "gram per gram” basis and abso ⁇ tion rate.
  • a liquid transport member composed of at least two regions exhibiting a difference in permeability. It is a further object to provide liquid transport members exhibiting improved liquid transport, as expressed in significantly increased liquid flow rates, and especially liquid flux rates, i.e. the amount of liquid flowing in a time unit through a certain cross-section of the liquid transport member. It is a further object of the present invention to allow such liquid transport against gravity.
  • a liquid transport member according to the present invention can comprise a first region comprising a first materials and further can comprise an additional element in contact with the first material of the first region which extends into a neighbouring second region of the liquid transport member.
  • the additional element can be in contact with the wall region and can extend into the neighbouring second region, and has a capillary pressure for absorbing the liquid that is lower than the bubble point pressure of the member.
  • This additional element can comprise a softness layer.
  • the ratio of permeability of the bulk region and the permeability of the port region is at least 10. preferably at least 100, more preferably at least 1000, and even more preferably at least 100,000.
  • the port region has a bubble point pressure of at least 1 kPa, preferably of at least 2 kPa, more preferably at least 4.5 kPa, even more preferably 8 kPa, most preferably 50 kpa, when measured with a test liquid having a surface tension of 72 mN/m, and a having a bubble point pressure of at least 0.67 kPa, preferably of at least 1.3 kPa, more preferably at least 3 kPa, even more preferably at least 5.3 kPa, and most preferably at least 33 kPa when measure with a test liquid having a surface tension of 33 mN/m.
  • the bulk region has a larger average pore size than said port regions, such that the ratio of average pore size of the bulk region and the average pore size of the port region is preferably at least 10, more preferably at least 50, even more preferably at least 100, or even at least 500, and most preferably at least 1000.
  • the bulk region has an average pore size of at least 200 ⁇ m, preferably at least 500 ⁇ m, more preferably of at least 1000 ⁇ m, and most preferably of at least 5000 ⁇ m.
  • the bulk region has a porosity of at least 50%, preferably at least 80%, more preferably at least 90%, even more preferably of at least 98%, and most preferably of at least 99%.
  • the bulk region can have a density which exceeds 0.001 g/cm 3 .
  • the port region has a porosity of at least 10%, more preferably at least 20%, even more preferably of at least 30%, and most preferably of at least 50%.
  • the port regions have an average pore size of no more than 100 ⁇ m, preferably no more than 50 ⁇ m, more preferably of no more than 10 ⁇ m, and most preferably of no more than 5 ⁇ m. It is also preferred, that the port regions have a pore size of at least 1 ⁇ m, more preferably at least 3 ⁇ m.
  • the port regions have an average thickness of no more than 100 ⁇ m, preferably no more than 50 ⁇ m, more preferably of no more than 10 ⁇ m, and most preferably of no more than 5 ⁇ m.
  • the bulk regions and the wall regions have a volume ratio (bulk to wall region) of at least 10, preferably at least 100, more preferably at least 1000, and even more preferably at least 10000.
  • the wall region comprises a material selected from the groups of fibers, particulates, foams, spirals, films, corrugated sheets, tubes, woven webs, woven fiber meshes, apertured films, or monolithic films.
  • the liquid transport member comprises fibers, which are made of polyolefins, polyesters, polyamids, polyethers, polyacrylics, polyurethanes, metal, glass, cellulose, cellulose derivatives.
  • the liquid transport member is made by a porous bulk region that is wrapped by a separate wall region.
  • the member may comprise water soluble materials, for example to increase permeability or pore size upon contact with the liquid in the bulk or port regions.
  • the liquid transport member is initially wetted by or essentially filled with liquid, or is under vacuum.
  • a liquid transport member can be particularly suitable to transport of water- based liquids, of viscoelastic liquids, or for bodily exudates such as urine, blood, menses, feces or sweat.
  • a liquid transport member can also be suitable for transport of oil, grease, or other non-water based liquids, and it can be particularly suitable for selective transport of oil or grease, but not water based liquids.
  • the port regions may be hydrophobic.
  • the properties or parameter of any of the regions of the member or of the member itself need not to be maintained during the transport of the member from its production to the intended use, but that these are established just prior to or at the time of liquid handling. This may be achieved by having an activation of the member, such as contact with the transported liquid, pH, temperature, enzymes, chemical reaction, salt concentration or mechanical activation.
  • Another aspect of the present invention concerns the combination of a liquid transport member with either a source of liquid and/or the sink of liquid, with at least one of these being positioned outside of the member.
  • a liquid transport system comprising a liquid transport member according to the present invention, wherein the system has an abso ⁇ tion capacity of at least 5 g/g, preferably at least 10 g/g, more preferably at least 20 g/g, on the weight basis of the sink material when measured in the Demand Absorbency Test.
  • the liquid transport system contains a sink material that has an absorption capacity of at least 10 g/g, preferably at least 20 g/g and more preferably at least 50 g/g on the basis of the weight of the sink material, when submitted to the Teabag Centrifuge Capacity Test.
  • the sink material that has an absorbent capacity of at least 5 g/g, preferably at least 10 g/g, more preferably of at least 50 g/g when measured in the Capillary Suction Test at a pressure up to the bubble point pressure of the port region, and which has an absorbent capacity of less than 5 g/g, preferably less than 2 g/g, more preferably less than 1 g/g, and most preferably of less than 0.2 g/g when measured in the Capillary Suction Test at a pressure exceeding the bubble point pressure of the region.
  • the liquid transport member also contains superabsorbent materials or foam made according to the High Internal Phase emulsion polymerization.
  • An even further aspect of the present invention relates to an article comprising a liquid transport member according to the present invention, such as an absorbent article or a disposable absorbent article comprising a liquid transport member.
  • a liquid transport member according to the present invention such as an absorbent article or a disposable absorbent article comprising a liquid transport member.
  • An application, which can particularly benefit from using members according to the present invention is a disposable absorbent hygiene article, such a baby or adult incontinence diaper, a feminine protection pad, a pantiliner, a training pant. Other suitable applications can be found for a bandage, or other health care absorbent systems.
  • the article can be a water transport system or member, optionally combining transport functionality with filtration functionality, e.g. by purifying water which is transported.
  • a liquid transport member according to the present invention can also be a oil or grease absorber, or can be used for separation of oily and aqueous liquids.
  • Yet another aspect of the present invention relates to the method of making a liquid transport member, wherein the method comprises the steps of a) providing a bulk or inner material; b) providing a wall material comprising a part region; c) completely enclosing said bulk region material by said wall material; d) providing a transport enablement means selected from d1) vacuum; d2) liquid filling; d3) expandable elastics / springs;
  • the method can comprise the step of e) applying activation means of e1) liquid dissolving port region; e2) liquid dissolving expandable eiastication / springs. e3) removable release element; e4) removable sealing packaging.
  • the method may comprise the steps of: a) wrapping a highly porous bulk material with a separate wall material that contains at least one permeable port region, b) completely sealing the wall region, and c) evacuating the member essentially of air.
  • the method further comprises the step wetting the member, or partially of essentially fully filling the member with liquid.
  • Fig. 2 Schematic diagram of a liquid transport member according to the present invention.
  • Fig. 3 A, B Conventional Siphon system, and liquid transport member according to the present invention.
  • Fig. 4 Schematic cross-sectional view through a liquid transport member.
  • Fig. 5 A, B, C Schematic representation for the determination of port region thickness.
  • Fig. 6 Correlation of permeability and bubble point pressure.
  • Fig. 7 to 12 Schematic diagrams of various embodiments of liquid transport member according to the present invention.
  • Fig. 13 A, B, C Liquid Transport Systems according to the present invention.
  • a “liquid transport member” refers to a material or a composite of materials, which is able to transport liquids. Such a member contains at least two regions, an “inner” region, for which the term "bulk” region
  • inner region 7o can be used interchangeably, and a wall region comprising at least one "port" region.
  • outer region refers to the relative positioning of the regions, namely meaning, that the outer region generally circumscribes the inner region, such as a wall region circumscribing a bulk region.
  • the Z-dimension usually corresponds to the thickness of the liquid transport member or the article.
  • the term "X-Y dimension” refers to the plane orthogonal to the thickness of the member, or article.
  • the X-Y dimension usually corresponds to the length and width, respectively, of the liquid transport member, or article.
  • layer also can apply to a member, which - when describing it in spherical or cylindrical co-ordinates - extends in radial direction much less than in the other ones.
  • the skin of a balloon would be considered a layer in this context, whereby the skin would define the wall region, and the air filled center part the inner region.
  • the term "absorbent articles” refers to devices which absorb and contain body exudates, and, more specifically, refers to devices which are placed against or in proximity to the body of the wearer to absorb and contain the various exudates discharged from the body.
  • body fluids includes, but is not limited to, urine, menses and vaginal discharges, sweat and feces.
  • the term "absorbent core” refers to the component of the absorbent article that is primarily responsible for fluid handling properties of the article, including acquiring, transporting, distributing and storing body fluids. As such, the absorbent core typically does not include the topsheet or backsheet of the absorbent article.
  • a member or material can be described by having a certain structure, such as a porosity, which is defined by the ratio of the volume of the solid matter of the member or material to the total volume of the member or material.
  • activatable refers to the situation, where a certain ability is restricted by a certain means, such that upon release of this means a reaction such as a mechanical response happens.
  • the expansion can be defined by the elastic modulus, as well known in the art.
  • the basic functioning mechanism of the present invention can be best explained by comparing it to conventional materials.
  • the liquid transport is based on capillary pressure as the driving force
  • the liquid is pulled into the pores that were initially dry by the interaction of the liquid with the surface of the pores. Filling the pores with liquid replaces the air in these pores.
  • a conventional capillary flow material is connected at one end to a liquid source (e.g., a reservoir) and on the other end to a liquid sink (e.g., a hydrostatic suction), the liquid transport through this material is based on the abso ⁇ tion / deso ⁇ tion and re-absorption cycle of the individual pores with the capillary force at the liquid / air-interface providing the internal driving force for the liquid through the material.
  • a liquid source e.g., a reservoir
  • a liquid sink e.g., a hydrostatic suction
  • a simplifying explanation for the functioning of the present invention can start with comparing it to a siphon (refer to Fig. 1), well known from drainage systems as a tubing in form of a laying "S" (101).
  • the principle thereof is, that - once the tubing (102) is filled with liquid (103) - upon receipt of further liquid (as indicated by 106) - entering the siphon at one end, almost immediately liquid leaves the siphon at the other end (as indicated by 107), as - because the siphon is being filled with incompressible liquid - the entering liquid is immediately displacing liquid in the siphon forcing the liquid at the other end to exit the siphon, if there is a pressure difference for the liquid between the point of entry and the point of exit of said siphon.
  • liquid is entering and leaving the system through an open surface inlet and outlet "port regions" (104 and 105 respectively).
  • the driving pressure to move liquid along the siphon can be obtained via a variety of mechanisms. For example, if the inlet is at a higher position than the outlet, gravity will generate a hydrostatic pressure difference generating liquid flow through the system.
  • the liquid transport member (201) does not need to be s-shaped, but can be a straight tube (202).
  • the inlet and/or outlet ports are not open surfaces, but have special permeability requirements as explained in more detail hereinafter, which prevent air or gas from penetrating into the transport member, thus the transport member remains filled with liquid.
  • a liquid transport member according to the present invention can be combined with one or more liquid source(s) and/or sink(s) to form a liquid transport system.
  • Such liquid sources or sinks can be attached to the transport member such as at inlet and/or outlet regions or the sink or the source can be integral with the member.
  • a liquid sink can be - for example - integral with the transport member, when the transport member can expand its volume thereby receiving the transported liquid.
  • Transport System can be seen in Fig. 3 A (siphon) and 3B (present invention).
  • a liquid (source) reservoir (301) with a lower (in the direction of gravity) liquid (sink) reservoir (302) by a conventional tube or pipe with open ends (303) in the shape on an inverted “U” (or "J")
  • liquid can flow from the upper to the lower reservoir only if the tube is kept full with liquid by having the upper end immersed in liquid. If air can enter the pipe such as by removing the upper end (305) from the liquid, the transport will be interrupted, and the tube must be refilled to be functional again.
  • a liquid transport member according to the present invention would look very similar in an analog arrangement, except for the ends of the transport member, inlet (305) and outlet port (306), comprising inlet and outlet port materials with special permeability requirements as explained in more detail hereinafter instead of open areas.
  • the inlet and outlet materials prevent air or gas from penetrating into the transport member, and thereby maintain the liquid transport capability even if the inlet is not immersed into the liquid source reservoir. If the transport member is not immersed into the liquid source reservoir, liquid transport will obviously stop, but can commence immediately upon re-immersion.
  • the present invention is concerned with liquid transport, which is based upon direct suction rather than on capillarity.
  • the liquid is transported through a region through which substantially no air (or other gas) should enter this member (or at least not in a significant amount).
  • the driving force for liquid flowing through such a member can be created by a liquid sink and liquid source in liquid communication with the member, either externally, or internally.
  • transport liquid refers to the liquid which is actually transported by the transport member, i.e., this can be the total of a homogeneous phase, or it can be the solvent in a phase comprising dissolved matter, e.g., the water of a aqueous salt solution, or it can be one phase in a multiphase liquid, or it can be that the total of the multicomponent or multiphase liquid.
  • liquid the respective liquid properties e.g., the surface energy, viscosity, density, etc., are relevant in for various embodiments.
  • the liquid entering the liquid transport member will be the same or of the same type as the liquid leaving the member or being stored therein, this does not necessarily need to be the case.
  • the aqueous phase may leave the member first.
  • the aqueous phase could be considered "replaceable liquid".
  • the transport path can be defined as the path of a liquid entering a port region and the liquid exiting a port region, 5 whereby the liquid transport path runs through the bulk region.
  • the transport path can also be defined by the path of a liquid entering a port region and then entering a fluid storage region which is integral within the inner region of the transport member, or alternatively defined as the path of a liquid from a liquid releasing source region within the inner region of the transport member to an o outlet port region.
  • the transport path of an liquid transport member can be of substantial length, a length of 100 m or even more can be contemplated, alternatively, the liquid transport member can also be of quite short length, such as a few millimeters or even less.
  • liquid transport member should be substantially impermeable for air or gas during the liquid transport.
  • the property requirements have to be fulfilled at the time of liquid transport. It can be, however, that these are created or adjusted by activating a transport member, e.g., prior to usage, which - without or prior to such activation - would not satisfy the requirements but does so after activation.
  • a transport member e.g., prior to usage, which - without or prior to such activation - would not satisfy the requirements but does so after activation.
  • a member can be elastically compressed or collapsed, and expand upon wetting to then create a structure with the required properties.
  • liquid is removed at one end of a capillary system such as by a suction means, this liquid is desorbed out of the capillaries closest to this suction device, which are then at least partially filled by air, and which are then refilled through capillary pressure by liquid from adjacent capillaries, which are then filled by liquid from following adjacent capillaries and so on.
  • liquid transport through a conventional capillary flow structure is based upon abso ⁇ tion - deso ⁇ tion and re-abso ⁇ tion cycle of the individual pores.
  • the flow respectively flux is determined by the average permeability along the pathway and by the suction at the end of the transport path.
  • Such a local suction will generally also be dependent on the local saturation of the material, i.e. if the suction device is able to reduce the saturation of the region close to it, the flow/flux will be higher.
  • a specific idealized execution of such porous liquid transport members are so-called “capillary tubes”, which can be described as parallel pipes with the inner tube diameter and wall thickness defining the overall openness (or porosity) of the system.
  • Such systems will have a relative large flux against a certain height if these are "mono-porous", i.e., if the pores have the same, optimal pore size. Then the flow is determined by the pore structure, the surface energy relation, and the cross-sectional area of the porous system, and can be estimated by well know approximations.
  • Realistic porous structures such as fibrous or foam type structures, will not transport like the ideal structures of capillary tubes.
  • Realistic porous structures have pores that are not aligned, i.e. not straight, as the capillary tubes and the pore sizes are also non-uniform. Both of these effects often reduce the transport efficiency of such capillary systems.
  • the port regions do not require a specific directionality of their properties, i.e. the materials used therein can be used in either orientation of liquid flow there through.
  • the membranes it a requirement for the membranes to have different properties (such as permeability) with regard to certain parts or components of the liquid. This is in contrast to the membranes such as described for osmotic absorbent packets in US-A-5.108.383 (White et al.), where the membranes have to have a low permeability for the promoter material, such a salt, respectively salt-ions.
  • a key requirement for the bulk region is to have a low average flow resistance, such as expressed by having a permeability k of at least 10 11 m 2 , preferably more than 10 "8 m 2 ., more preferably more than 10 '7 m 2 , and most preferably more than 10 '5 m 2 .
  • This density corresponds to the so called dry density, as determined for the material or region not being filled with fluids like liquids or gases, and is measured under low pressure, such as 0.02 psi. If the bulk region is not a void, but rather a porous material, such a material will have densities of more than about 0.001 g/m 2 .
  • the inner region can have pores, which are larger than about 200 ⁇ m, 500 ⁇ m, 1 mm or even 9 mm in diameter or more.
  • the inner region can have pores as large as 10 cm - e.g. when the inner region is a void tube.
  • the inner regions can have various forms or shapes.
  • the inner region can be cylindrical, ellipsoidal, sheet like, stripe like, or can have any irregular shape.
  • the inner regions can have constant cross-sectional area, with constant or varying cross-sectional shape, like rectangular, triangular, circular, elliptical, or irregular.
  • a cross-sectional area is defined for the use herein as a cross-section of the inner region, prior to addition of source liquid, when measured in the plane perpendicular to the flow path of the transport liquid, and this definition will be used to determine the average inner region cross-sectional area by averaging the individual cross-sectional areas all over the flow path(s).
  • the absolute size of the inner region should be selected to suitably match the geometric requirements of the intended use. Generally, it will be desirable to have the minimum dimension for the intended use. A benefit of the designs according to the present invention is to allow much smaller cross-sectional areas than conventional materials.
  • the dimensions of the inner region are determined by the permeability of said inner region, which can be very high, due to possible large pores, as the inner region does not have to be designed under the contradicting requirements of high flux (i.e. large pores) and high vertical liquid transport (i.e. small pores). Such large pemeabilities allow much smaller cross- sections, and hence very different designs.
  • the inner region can change its shape, such as under deforming forces or pressures during use, or under the influence of the fluid itself.
  • the deformabiiity or absence thereof can be achieved by selection of one or more materials in the inner region (such as a fibrous member), or can be essentially determined by the circumscribing regions, such as by the wall regions of the transport member.
  • One such approach is to utilize elastomeric materials as the wall material.
  • such materials may fill larger pores, completely or partially,
  • the inner region can comprise soluble materials, such as poly(vinyl) alcohol or poly(vinyl) acetate.
  • soluble materials such as poly(vinyl) alcohol or poly(vinyl) acetate.
  • Such materials can fill the voids, or support a collapsed state of the voids before the member is contacted with liquid. Upon contact with fluid, such as water, these materials may dissolve and thereby create empty or expanded voids.
  • most of the void volume preferably more than 90%, more preferably more than 95%, and even more preferably more than 99%, including 100%, is filled with the liquid.
  • the inner region can be designed so as to enhance accumulation of gas or other liquid in parts of the region where it is less detrimental.
  • the remainder of the voids can then be filled with other fluid, such as residual gas or vapors, or immiscible liquid like oil in an inner region filled with aqueous liquids, or can be solids, like particulates, fibers, films.
  • the liquid comprised in the inner region can be of the same type as the liquid being intended to be transported.
  • the inner region of the transport member can be filled with water - or if oil is the intended transport liquid, the inner region can be filled with oil.
  • the total amount of transported liquid is limited by the amount which can be received within the member respectively the amount of liquid exchanged, unless there were, for example, outlet port regions comprising materials with properties compatible with the liquids so as to allow functionality with one or both of the liquids.
  • the liquid of the inner region and the liquid to be transported can be mutually soluble, such as salt solutions in water.
  • the inner region can be filled with water.
  • the inner region comprises a vacuum, or a gas or vapor below the corresponding equilibrium, ambient or external, pressure at the respective temperatures, and volumetric conditions.
  • the liquid can enter into the inner region by the permeable port regions (as described hereinafter), and then fill the voids of the inner region to the required degree. Thereafter, the now filled inner region functions like a "pre- filled" region as described in the above.
  • a simple and yet very descriptive example for an inner region is an empty tube defined by impermeable or semi-permeable walls, as already discussed and depicted in Fig. 2.
  • the diameter of such tubes can be relatively large compared to diameters commonly used for transport in capillary systems. The diameter of course depends highly on the specific system and intended use. For example, for hygiene applications such as diapers, pore sizes of 2 - 9 mm or more have been found to function satisfactorily.
  • Other materials can be suitable even when they do not satisfy all the above requirements at the same time, if this deficiency can be compensated by other design elements.
  • filter materials as open cell foams from Recticel in Brussel, Belgium such as Bulpren, Filtren (Filtren TM10 blue, Filtren TM20 blue, Filtren TM30 blue, Filtren Firend 10 black, Filtren Firend 30 black, Filtren HC 20 grey, Filtren Firend HC 30 grex, Bulpren S10 black, Bulpren S20 black, Bulpren S30 black).
  • Another material having relatively large pores - even though the porosity is not particularly high - is sand with particles larger than 1 mm, specifically sand with particles larger than 5 mm
  • Such fibrous or other materials may , for example become very useful by being corrugated, however, excessive compression should be avoided. Excessive compression can result in a non-homogeneous pore size distribution with small pores within the inner material, and insufficiently open pores between the corrugations.
  • a further embodiment to exemplify a material with two pore size regions can be seen in PCT application US97/20840, relating to a woven loop structure.
  • the inner region may comprise absorbent materials, such as super absorbent gelling materials or other materials as described for being suitable as a liquid sink material herein after. Further, the promoter materials of Membrane
  • Signals can be suitable for being used in the inner region.
  • the inner region may further be constructed form several materials, i.e. for example from combinations of the above.
  • the inner region may also comprise stripes, particulates, or other in- homogeneous structures generating large voids between themselves and acting as space holders.
  • the fluids in the inner region must not prevent the port regions from being filled with the transport liquid.
  • the degree of vacuum for example, or the degree of miscibility or immiscibility must not be such that liquids from the port region are drawn into the inner region without the port region(s) being refilled with transport liquid.
  • the liquid transport member according to the present invention comprises in addition to the inner regions a wall region circumscribing this inner region as geometrically defined hereinabove.
  • This wall region must comprise at least one port region, as described hereinafter.
  • the wall region can further comprise materials, which are essentially impermeable to liquids and/or gases, thereby not interfering with the liquid handling functionality of the port regions, and also preventing ambient gases or vapors from penetrating into the liquid transport member.
  • Such walls can be of any structure or shape, and can re present the key structural element of the liquid transport member.
  • Such walls can be in the shape of a straight or bent pipe, of a flexible pipe, or of cubical shape and so on.
  • the walls can be thin, flexible films, circumscribing the inner region.
  • Such walls can be expandable, either permanently via deformation or elastically via an elastomeric film, or upon activation.
  • the wall regions as such are an essential element for the present invention, this is particularly true for the port region comprised in such regions, and described in the following.
  • the properties of the remaining parts of the wall regions can be important for the overall structure, for resilience, and other structural effects.
  • the port regions can generally be described to comprise materials which have different permeabilities for different fluids, namely they should be permeable for the transport liquid, but not for the ambient gas (like air), under otherwise same conditions (like temperature, or pressure, ...) and once they are wetted with / filled with the transport liquid or similarly functioning liquid.
  • a membrane is generally defined as a region, that is permeable for liquid, gas or a suspension of particles in a liquid or gas.
  • the membrane may for example comprise a microporous region to provide liquid permeability through the capillaries.
  • the membrane may comprise a monolithic region comprising a block-copolymer through which the liquid is transported via diffusion.
  • membranes will often have selective transport properties for liquids, gases or suspensions depending on the type of medium to be transported. They are therefore widely used in filtration of fine particles out of suspensions (e.g. in liquid filtration, air filtration).
  • Other type of membranes show selective transport for different type of ions or molecules and are therefore found in biological systems (e.g. cell membranes, molecular sieves) or in chemical engineering applications (e.g. for reverse osmosis).
  • Microporous hydrophobic membranes will typically allow gas to permeate, while water-based liquids will not be transported through the membrane if the 5 driving pressure is below a threshold pressure commonly referred to as "breakthrough” or “bridging” pressure.
  • hydrophilic microporous membranes will transport water based liquids. Once wetted, however, gases (e.g. air) will essentially not pass through the membrane if the driving pressure is below a threshold pressure commonly o referred to as "bubble point pressure".
  • gases e.g. air
  • Hydrophilic monolithic films will typically allow water vapor to permeate, while gas will not be transported rapidly through the membrane.
  • membranes can also be used for non-water based liquids such as oils.
  • most hydrophobic materials will be in fact oleophilic.
  • a 5 hydrophobic microporous membrane will therefore be permeable for oil but not for water and can be used to transport oil, or also separate oil and water.
  • Membranes are often produced as thin sheets, and they can be used alone or in combination with a support layer (e.g. a nonwoven) or in a support element
  • membranes include but are not limited to o polymeric thin layers directly coated onto another material, bags, corrugated sheets.
  • membranes are "activatable” or “switchable” membranes that can change their properties after activation or in response to a stimulus. This change in properties might be permanent or reversible depending on the specific 5 use.
  • a hydrophobic microporous layer may be coated with a thin dissolvable layer e.g. made from poly(vinyl)alcohol.
  • a double layer system will be impermeable to gas.
  • the poly(vinyl)aicohol film once wetted and the poly(vinyl)aicohol film has been dissolved, the system will be permeable for gas but still impermeable for aqueous liquid.
  • a hydrophilic membrane is coated by such a soluble layer, it might become activated upon liquid contact to allow liquid to pass through, but not air.
  • a hydrophilic microporous membrane is initially dry. In this state the membrane is permeable for air. Once wetted with water, the membrane is no longer air permeable.
  • a microporous membrane coated with a surfactant that changes its hydrophilicity depending on temperature. For example the membrane will then be hydrophilic for warm liquid and hydrophobic for cold liquid. As a result, warm liquid will pass through the membrane while cold liquid will not.
  • Other examples include but are not limited to microporous membranes made from an stimulus activated gel that changes it ' s dimensions in response to pH, temperature, electrical fields, radiation or the like.
  • the port regions can be described by a number or properties and parameters.
  • a key aspect of the port region is the permeability.
  • a volumetric flow dV/dt through the membrane is caused by an external pressure difference ⁇ p (driving pressure), and the permeability function k may depend on the type of medium to be transported (e.g. liquid or gas), a threshold pressure, and a stimulus or activation. Further relevant parameters impacting on the liquid transport are the cross-section A, the volume V respectively the change over time thereof, and the length L of the transport regions, and the viscosity ⁇ of the transported liquid.
  • the macroscopic transport properties are mainly depending on the pore size distribution, the porosity, the tortuosity and the surface properties such as hydrophilicity.
  • the permeability of the port regions should be high so as to allow large flux rates there through.
  • typical permeability values for port regions or port region materials will range from about 6 * 10 '20 m 2 , to 7 * 10 '18 m 2 , or
  • a further parameter relevant for port regions and respective materials is the bubble point pressure, which can be measured according to the method as described hereinafter.
  • Suitable bubble point pressure values depend on the type of application in mind.
  • the table below lists ranges of suitable port region bubble point pressure (bpp) for some applications, as determined for respective typical fluids:: Application bpp (kPa) broad range typical range
  • the port region of a liquid transport member is defined as the part of the wall having the highest permeability.
  • the port region is also defined by having the lowest relative permeability when looking along a path from the bulk region to a point outside the transport member.
  • the port region can be constructed by readily discernible materials, and then both thickness and size can be readily determined.
  • the port region can, however, have a gradual transition of its properties either to other, impermeable regions of the wall region, or to the bulk region. Then the determination of the thickness and of the size can be made as described hereinafter. When looking at a segment of the wall region, such as depicted in Figure 5A, this will have a surface, defined by the cornerpoints ABCD, which is oriented towards the inner or bulk region, and a surface EFGH oriented towards the outside of the member.
  • the thickness dimension is oriented along the lines AE, BF, and so on, i.e. when using Cartesian co-ordinates, along the z-direction.
  • the wall region will have the major extension along the two pe ⁇ endicular directions, i.e. x-, and y- direction.
  • the port region thickness can be determined as follows: a) In case of essentially homogeneous port region properties at least in the direction through the thickness of the region, it is the thickness of a material having such a homogeneous permeability (such as with a membrane film). b) It is the thickness of the membrane if this is combined with a carrier (be this carrier inside or outside of the membrane) - i.e.
  • the "upper port region permeability" is determined as being 10 times the value of k m ⁇ n c3) As the curve has a minimum at k m ⁇ n there will be two corresponding r ⁇ nner ar
  • Typical thickness values are in the range of less than 100 ⁇ m, often less than 50 ⁇ m, 10 ⁇ m, or even less than 5 ⁇ m.
  • the x-y extension of the port region can be determined.
  • which part of the wall region are port regions.
  • the local permeability curves along the x- and y direction of the wall region can be determined, and plotted analogously to Figure 5B as shown in Figure 5C.
  • the maximum permeability in the wall region defines the port regions, hence the maximum will be determined, and the region having permeabilities of not less than a tenth of the maximum permeability surrounding this maximum is defined as the port region.
  • Yet another parameter useful for describing aspects of the port regions useful for the present invention is the permeability to thickness ratio, which in the context of the present invention is also referred to as "membrane conductivity".
  • this parameter can be very useful for designing the port region materials to be used.
  • Suitable conductivity k/d depends on the type of application in mind. The table below lists ranges of typical k/d for some exemplary applications: Application k/d (10 "9 m) broad range typical range Diapers 10 "6 to 1000 150 to 300
  • the port regions have to be wettable by the transport fluid, and the hydrophilicity or lipophilicity should be designed appropriately, such as by using hydrophilic membranes in case of transporting aqueous liquids, or oleophilic membranes in case of lipophilic or oily liquids.
  • the surface properties in the port region can be permanent, or they can change with time, or usage conditions.
  • a porous membrane to be functional once wetted permeable for liquid, not-permeable for air
  • at least a continuous layer of pores of the membrane always need to be filled with liquid and not with gas or air.
  • the pores have preferably an average size of less than 100 ⁇ m, preferably less than 50 ⁇ m, more preferably less than 10 ⁇ m or even less than 5 ⁇ m. Typically, these pores are not smaller than 1 ⁇ m.
  • bubble point pressure It is an important feature for example of the bubble point pressure, that this will depend on the largest pores in the region, which are in a connected arrangement therein. For example, having one larger pore embedded in small ones does not necessarily harm the performance, whilst a "cluster" of larger pores together might very well do so.
  • pore walls such as pore wall thickness
  • the pores should be well connected to each other along the flow direction, to allow liquid passing through readily.
  • the preferred port region materials can be thin membrane materials, these in themselves may have relatively poor mechanical properties.
  • a support structure such as a coarser mesh, threads or filaments, non-woven, apertured films, or the like.
  • Such a support structure could be combined with the membrane such that it is positioned towards the inner / bulk region or towards the outside of the member.
  • the size of the port regions is essential for the overall performance of the transport member, and needs to be determined in combination with the "permeability to thickness" ( /d) ratI0 of the port region.
  • the size has to be adapted to the intended use, so as to satisfy the liquid handling requirements.
  • the flux (i.e. the flow rate through a unit area) of the port regions will generally be lower than the flux through the inner region, it may be preferred - in addition to or alternatively to reduction of port region thickness - to design the port regions larger in size (surface) than the cross-section of the inner region.
  • the exact design and shape of the port regions can vary over a wide range.
  • the port regions can be relatively small, such as about the size of the cross-section of the inner region, such that a substantially smaller transport member results.
  • One essentially continuous material can have a gradient of properties along either the surface of the material, in the thickness dimension, or both, so as to be able to represent several inlet/outlet/wall regions.
  • metal filter meshes of the appropriate pore size can be suitable, such as HIGHFLOW of Haver & B ⁇ cker, in Oelde, Germany. Additional Elements
  • a further property of the liquid transport member is the permeability k (liquid transport member) as the average permeability along the flow path of the transported liquid.
  • the liquid transport member according to the present invention has a permeability which is higher than the permeability of a capillary system with equal liquid transport capability. This property is referred to as the a "critical permeability".
  • the critical permeability of the liquid transport member of the present invention is preferably at least twice as high as a capillary system with equal vertical liquid transport capability more preferably at least four times as high, and most preferably at least ten times greater than a capillary system with equal vertical liquid transport capability.
  • the liquid transport member according to the present invention should have a relatively high bpp ⁇ liquid transport member ⁇ and a high k ⁇ liquid transport member ⁇ at the same time.
  • This can be graphically represented when plotting k ⁇ liquid transport member ⁇ over bbp in a double logarithmic diagram (as in Fig. 6 wherein the bbp is expressed in "cm height of water column", which then can be readily converted into a pressure).
  • a top left to down right correlation can be observed.
  • Members according to the present invention are have properties in the upper right region (I) above the separation line (L), whilst properties of conventional materials are much more in the left lower corner in the region (II), and have the limitations of the pure capillary transport mechanism, as schematically indicated by the straight line in the log-log diagram.
  • a liquid transport member according to the present invention can further be described by having high flux rates, as calculated on the cross-sectional area of the inner region.
  • the member should have an average flux rate at 0.9kPa additional suction pressure differential to the height H 0 when tested in the Liquid Transport test at a height H 0 , as described herein after, of at least 0.1g/s/cm 2 , preferably of at least 1g/cm 2 /sec, more preferably at least 5g/cm 2 /sec, even more preferably at least 10g/cm 2 /sec, or even at least 20g/cm 2 /sec, and most preferably at least 50g/cm 2 /sec.
  • the liquid transport member should have a certain mechanical resistance against external pressure or forces.
  • this resistance can be in a medium range, thus allowing exploitation of external pressure or forces on the transport member for creating a "pumping effect".
  • the permeability requirement can be satisfied by the membrane itself, i.e. not considering the effect of the support structure, if the support structure is sufficiently open to have no negative impact on the overall permeability or on the liquid handling properties thereof.
  • the thickness of the port region refers to the thickness of the membrane only - i.e. not including the thickness of the support structure. It will become apparent in the specific context, if for example such a support structure should be seen as an element of the port region having no significant impact on the port region properties, or - for example if the support structure has a significant thickness and thus impacts on the permeability for the liquid after the port region is penetrated - whether the support structure should be considered as a part of the inner region.
  • both the inner/bulk region and the port regions can be determined independently, it is preferred that one or both of the port regions have a lower liquid permeability than the inner region.
  • a liquid transport member should have a ratio of the permeability of the bulk region to the port region of preferably at least 10:1 , more preferably at least 100:1, even more preferably at least 1000:1 , even ratios of 100000:1 can be suitable.
  • At least a portion of the port region(s) have to be in liquid communication with the inner region, so as to allow fluid to be transferred thereto.
  • the inner/bulk region should comprise larger pores than the wall region.
  • the pore size ratio of inner pores to port region pores are preferably at least 3: 1 , or 10:1, more preferably at least 30:1 , even more preferably at least 100:1 and most preferable at least 350:1.
  • the area of the port regions will typically be as large as or larger than the cross-section of the inner regions, thereby considering the respective regions together, namely - if present - the inlet regions or respectively the outlet regions.
  • the port regions will be twice as large as said inner region cross-section, often four times as large, or even 10 times as large.
  • Structural relation of regions The various regions can have similar structural properties or different, possibly complementing structural properties, such as strength, flexibility, and the like.
  • all regions can comprise flexible material designed to cooperatively deform, whereby the inner region comprises a thin-until-wet material which expands upon contact with the transported liquid, the port region(s) comprise flexible membranes, and the walls can be made of liquid impermeable flexible film.
  • the liquid transport member can be made of various materials, whereby each region may comprise one or more materials.
  • the inner region may comprise porous materials; the walls may comprise a film material, and the ports may comprise a membrane material.
  • the transport member may consist essentially of one material with different properties in various regions, such as a foam with very large pores to provide the functionality of the inner region, and smaller pores with membrane functionality surrounding these to function as port materials.
  • One way to look at a liquid transport member is to see the inner region being enclosed by at least one wall and/or port region.
  • a very simple example for this is the above mentioned tube filled with liquid and closed by membranes at both ends, as indicated in Figure 7.
  • Such members can be considered to be a "Closed Distribution Member", as the inner region (703) is "enclosed” by the wall region (702) comprising port regions (706, 707). It is characteristic for such systems, that - once the transport member is activated, or equilibrated - a puncturing of the wall region can interrupt the transport mechanism. The transport mechanism can be maintained if only a small amount of air enters the system. This small quantity of air can be accumulated in an area of the inner region wherein it is not detrimental to the liquid transport mechanism.
  • the liquid transport member may comprise several inlet and/or several outlet port regions, for example as can be achieved by connecting a number of tubes (802) together and closing several end openings with inlet ports 806 and an outlet port 807, 5 thereby circumscribing the inner region 803, or a "split" system where fluid is transported simultaneously to more than one location (more than one exit port).
  • the transport to different locations may be selective (e.g., the voids in a transport material on the route to one port may be filled with a water soluble material, and the voids in the transport material on the route to a second port 0 may be filled with an oil soluble material.
  • the transport medium may be hydro- and/or oleo-philic to further enhance the selectivity.
  • the inner region (903) can be segmented into more than one region, such as can be visualized by looking a bundle of parallel pipes, held in position by any suitable fixation means 5 (909), circumscribed by a wall region (902), comprising port regions (906, 907), and the inner separation means (908). It also can be contemplated, that at least some of the membrane material is placed inside the inner/bulk regions, and the membrane material can even form the walls of the pipes.
  • the outer wall region consists o essentially of permeable port region with inlet (1006) and outlet (1007) port regions, i.e., the inner region (1003) is not circumscribed by any impermeable region at all.
  • the inlet and outlet port regions may have the same permeability, or can have a different degree of permeability.
  • the port regions and the inner region can be connected by a gradual transition region, such that the transport 5 member appears to be a unitary material with varying properties.
  • the liquid transport member can have one inlet and one outlet port region (1106 resp. 1107), and the member can be designed to receive and/or release liquid.
  • parts of the wall region (1102) can be deformable, such that the total member can increase the volume o of the inner region (1103), so as to accommodate the additionally received volume of liquid, or so as to accommodate the initially contained liquid, which then can be released through the port region(s).
  • a liquid sink or source can be integrally combined with the liquid transport member. This can be achieved by a liquid sink or source integrally incorporated in the member, such as depicted by element (1111) in Fig. 11.
  • a further embodiment can comprise highly absorbent materials such as superabsorbent materials or other highly absorbent materials as described in more detail in U.S. Patent Application Serial No.09/042429, filed March 13, 1998 by T. DesMarais et al, which is incorporated herein by reference, combined with a port region made of a suitable membrane, and flexibly expandable walls to allow for an increase in the volume of the storage member.
  • a further embodiment of such an system with a liquid sink integral with the liquid transport member is a "Thin-until-wet" material in combination with a suitable membrane.
  • Such materials are well known such as from US-A-5.108.383, which are open celled porous hydrophilic foam materials, such as produced by High Internal Phase Emulsion process.
  • the inner region can be void of liquid at the beginning of the liquid transport process (i.e., contains a gas at a pressure less than the ambient pressure surrounding the liquid transport member).
  • the liquid supplied by a liquid source can penetrate through the inlet port region(s) to first fill the voids of the membrane and then the inner region. The wetting then initiates the transport mechanisms according to the present invention thereby wetting, and penetrating the outlet port region.
  • the inner regions may not be completely filled with the transport fluid, but a certain amount of residual gas or vapor may be retained.
  • the gas or vapor is soluble in the transported liquid, it is possible that after some liquid passes through the member, that substantially all of the initially present gas or vapor is removed, and the inner regions become substantially free of voids. Of course, in cases with some residual gas or vapor being present in the inner region, this may reduce the effective available cross-section of the fluid member, unless specific measures are taken, such as indicated in Fig.12, with wall region (1202) comprising port regions (1206 and 1207) circumscribing the inner region (1203) and with region (1210) to allow gas to accumulate.
  • the member can be filled with an aqueous based liquid, and the transport mechanism is such, that a non-aqueous, possibly immiscible liquid (like oil) enters the liquid transport member via the inlet port while the aqueous liquid leaves the member via the outlet port.
  • a non-aqueous, possibly immiscible liquid like oil
  • a Liquid Transport System within the scope of the present invention comprises the combination of at least one liquid transport member with at least one further liquid sink or source in liquid communication with the member.
  • a system can further comprise multiple sinks or sources, and also can comprise multiple liquid transport members, such as in a parallel functionality The latter can create a rundancy, so as to ensure functionality of the system, even if a transport member fails.
  • the source can be any form of free liquid or loosely bound liquid so as to be readily available to be received by the transport member.
  • the sink can be any form of a liquid receiving region. In certain embodiments, it is preferred to have the liquid more tightly bound than the liquid in the liquid source.
  • the sink can also be an element or region containing free liquid, such that the liquid would be able to flow freely or gravity driven away from the member.
  • the sink can contain absorbent, or superabsorbent material, absorbent foams, expandable foams, alternatively it can be made of a spring activated bellows system, or it can contain osmotically functioning material, or combinations thereof.
  • Liquid communication in this context refers to the ability of liquids to transfer or to be transferred from the sink or source to the member, such as can be readily achieved by contacting the elements, or bringing the elements so closely together, that the liquid can bridge the remaining gap.
  • Such a liquid transport system comprises a liquid transport member according to the above description plus at least one liquid sink or source.
  • the liquid transport member can have liquid releasing or receiving properties in addition to a sink or source outside of the member.
  • the port region(s) must be in liquid communication with the source liquid and where applicable the sink material.
  • One approach is to have the port region material form the outer surface of the liquid transport member, in part or as the whole outer surface, so as to allow liquids such as liquids of the liquid source or sink to readily contact the port regions.
  • the effective port region size can be determined by the size of the liquid communication with the sink or source respectively. For example, the total of the port regions can be in contact with the sink or source, or only a part thereof. Alternatively, e.g., when there is one homogeneous port region, this can be distinguished into separate effective inlet port regions and effective outlet port regions where the port region is in contact with the liquid sink and/or source.
  • a liquid source for a liquid transport member according to the present invention can be a free flowing liquid, such as urine released by a wearer, or a open water reservoir.
  • a liquid source region can also be an. intermediate reservoir, such as a liquid acquisition member in absorbent articles.
  • a liquid sink can be a free flow channel, or an expanding reservoir, e.g., a bellowed element combined with mechanical expansion or spacer means, such as springs.
  • a liquid sink region (1303) can also be an ultimate liquid storage element of absorbent members, such as being useful in absorbent articles and the like.
  • Two or more liquid transport systems according to the present invention can also be arranged in a "cascading design" (Fig. 13), with wall regions (1302), port regions (1307) and liquid sink materials (1311).
  • Fig. 13 a "cascading design"
  • the overall fluid flow path will go through one liquid transport system after the next.
  • the inlet port region of a subsequent liquid transport system can take over the sink functionality of a previous system, such as when the inlet and outlet port regions are in fluid communication with each other.
  • Such a fluid communication can be direct contact, or can be via an intermediate material.
  • a specific embodiment of such a "cascade” can be seen in connecting two or more "membrane osmotic packets" comprising membranes of appropriate properties, whereby the osmotic suction power increases with subsequent packets.
  • Each of the packets can then be considered a liquid transport member, and the connection between the packets will define the inlet and outlet port regions of each packet or member.
  • the packets can be enclosed by one material (such as one type of flexible membrane), or even several packets can have a unitary membrane element.
  • a liquid transport system has an absorption capacity of at least 5 g/g, preferably at least 10 g/g, more preferably at least 50 g/g and most preferably at least 75 g/g on the basis of the weight of the liquid transport system, when measured in the Demand Absorbency Test as described hereinafter.
  • the liquid transport system contains a sink comprising an absorbent material having an abso ⁇ tion capacity of at least 10 g/g, preferably at least 20 g/g and more preferably at least 50 g/g, on the basis of the weight of the sink material, when measured in the Teabag Centrifuge Capacity Test as described hereinafter.
  • the liquid transport system comprises an absorbent material providing an absorbent capacity of at least 5 g/g, preferably at least 10 g/g, more preferably of at least 50 g/g or most preferably of at least 75 g/g up to the capillary suction corresponding to the bubble point pressure of the member, especially of at least 4kPa, preferably at least 10kPa, when submitted to the Capillary So ⁇ tion test as described herein.
  • Such materials exhibit preferably a low capacity in the capso ⁇ tion test above the bubble point pressure, such as 4kPa or even 10kPa, of less than 5 g/g, preferably less than 2 g/g, more preferably less than 1 g/g, and most preferably less than 0.2 g/g.
  • the liquid transport member also contains superabsorbent materials or foam made according to the High Internal Phase Emulsion polymerization, such as described in PCT application US98/05044, which is incorporated herein by reference.
  • the suction of the liquid sink material will not exceed the bubble point pressure of the port region.
  • the article can be a water transport system or member, optionally combining transport functionality with filtration functionality, e.g. by purifying water which is transported. Also, the member can be useful in cleaning operation, so as by removing liquids or as by releasing fluids in a controlled manner.
  • a liquid transport member according to the present invention can also be a oil or grease absorber.
  • the inlet port can be immersed into a reservoir, and the transport member can be in the form of a long tube.
  • known irrigation systems such as known under BLUMAT as available from Jade @ National Guild, PO Box 5370, Mt Crested Butte, CO 81225
  • the system according to the present invention will not loose its functionality upon drying of the reservoir, but remain functional until and after the reservoir is refilled.
  • An even further application can be seen in selective transport of liquids, such as when aiming at transporting oil away from an oil/water mixture.
  • a liquid transport member can be used to transfer the oil into a further reservoir.
  • oil can be transported into a liquid transport member comprising therein a sink functionality for oil.
  • An even further application uses the liquid transport member according to the present invention as a transmitter for a signal. In such an application, the total amount of transported liquid does not need to be very large, but rather the transport times should be short. This can be achieved, by having a liquid filled transport member, which upon receipt of even a little amount of liquid at the inlet port practically immediately releases liquid at the outlet port.
  • This liquid can then be used to stimulate further reaction, such as a signal or activated a response, e.g., dissolving a seal to release stored mechanical energy to create a three dimensional change in shape or structure.
  • a signal or activated a response e.g., dissolving a seal to release stored mechanical energy to create a three dimensional change in shape or structure.
  • a particularly useful application for such liquid transport members can be seen in the field of absorbent articles, such as disposable hygiene articles, such as baby diapers or the like, for disposable absorbent article.
  • the diaper 1420 is shown in Figure 14 in its flat-out, uncontracted state (i.e. with elastic induced contraction pulled out except in the side panels wherein the elastic is left in its relaxed condition) with portions of the structure being cut-away to more clearly show the construction of the diaper 1420 and with the portion of the diaper 1420 which faces away from the wearer, the outer surface 1452, facing the viewer.
  • Figure 14 shows a specific of the diaper 1420 in which the topsheet 1424 and the backsheet 1426 have length and width dimensions generally larger than those of the absorbent core 1428.
  • the topsheet 1424 and the backsheet 1426 extend beyond the edges of the absorbent core 1428 to thereby form the periphery 1460 of the diaper 1420.
  • the periphery 1460 defines the outer perimeter or, in other words, the edges of the diaper 1420.
  • the periphery 1460 comprises the longitudinal edges 1462 and the end edges 1464.
  • the absorbent core should be generally compressible, conformable, non- irritating to the wearer's skin, and capable of absorbing and retaining liquids such as urine and other certain body exudates.
  • the absorbent core has a garment surface, a body surface, side edges, and waist edges.
  • the absorbent core may - in addition to the liquid transport member according to the present invention - comprise a wide variety of liquid-absorbent or liquid handling materials commonly used in disposable diapers and other absorbent articles such as - but not limited to - comminuted wood pulp which is generally referred to as airfelt; meltblown polymers including coform; chemically stiffened, modified or cross-linked cellulosic fibers; tissue including tissue wraps and tissue laminates.
  • the inner regions can be filled with liquid, such as water, so as to be ready for liquid transport there through immediately after receipt of the liquid at the inlet port.
  • the inner region can be under a vacuum, which can suck in liquid through the inlet port such as upon activation of a barrier film like a polyvinyl alcohol film which can dissolve upon wetting.
  • a barrier film like a polyvinyl alcohol film which can dissolve upon wetting.
  • promotor materials for enhancing osmotic liquid storage mechanisms such as disclosed in the hereinbefore mentioned US-publication US-A-5.108.383 (White, Allied Signal) - can be within the inner region. In this instance, it may be preferable to have the inner region not prefilled - or at least not to a major degree - with transport liquid, but rather to keep the inner region under vacuum until the transport liquid is to be received.
  • the liquid transport members according to the present invention can be produced by various methods, which have to have in common the essential steps of combining a bulk or inner region with a wall region comprising port regions with appropriate selection of the respective properties as described in the above. This can be achieved by starting from a homogeneous material, and imparting therein different properties. For example, if a member is a polymeric foam material, this can be produced form one monomer with varying pore sizes, which will then be polymerized to form a suitable member. This can also be achieved by starting from various essentially homogeneous materials and combining these into the a member.
  • the bulk region can be filled with liquid, or can be subjected to vacuum, or can be equipped with other aids so as to created vacuum, or liquid filling.
  • the method of forming a member according to the present invention can comprise the step of applying activation means, which can be of the mechanical type, such as by providing a removable release element, such as being well known for example as a release paper for covering adhesives, or by providing a packaging design which allows the sealing of the member until use, whereby at the time of use such a packaging sealing is removed or opened.
  • This activation means can also comprise materials which react upon the transport liquid, such as dissolve. Such materials may be applied in the port regions, e.g. to open the port regions upon use, or such materials may be applied to the bulk regions, such as to allow expansion of these regions upon wetting.
  • the making of members according to the present invention can be done in an essentially continuous way, such as by having various materials provided in roll form, which are then unwound and processed, or any of the materials can be provided in discrete form, such as foam pieces, or particulates.
  • S-1.3f Polyamide mesh 03-10/2 of SEFAR in R ⁇ schlikon, Switzerland.
  • a ca 20 cm long tube (S-2.6) is connected in an air tight way with a plastic funnel (S-2.2). Sealing can be made with Parafilm M (available from
  • FIG. 18 A, B, C a further example for a liquid distribution member (1810), also useful for construction of disposable absorbent articles, such as diapers, is schematically depicted, omitting other elements such as adhesives and the like.
  • a sheet of three layers of HIPE foam produced as for S-1.4 each having a thickness of about 2 mm, and a corresponding basis weight of about 120 g/m 2 are positioned on the outlet port of a liquid transport member according to A-1.
  • the sheets were cut circular with a diameter of about 6 cm, and a segment of about 10° was cut out to provide better conformity to the port region surface.
  • a weight corresponding to a pressure of about 0.2 psi can be applied to enhance liquid contact between outlet and sink material.
  • activation means, that the member is put into the in use condition, such as by establishing a liquid communication along a flow path, or such as by initiating a driving pressure differential, and this can be achieved by mechanical activation simulating the pre-use activation of a user (such as the removal of a constraining means such as a clamp, or a strip of a release paper 5 such as with an adhesive, or removal of a package seal, thereby allowing mechanical expansion optionally with creation of a vacuum within the member).
  • a constraining means such as a clamp, or a strip of a release paper 5 such as with an adhesive, or removal of a package seal
  • Activation can further be achieved by another stimulus transmitted ton the member, such as pH or temperature change, by radiation or the like. Activation can also be achieved by interaction with liquids, such as having certain solubility o properties, or changing concentrations, or are carrying activation ingredients like enzymes. This can also be achieved by the transport liquid itself, and in these instances, the member should be immersed in testing liquid which should be representative for the transport liquid, optionally removing the air by means of a vacuum pump, and allowing equilibration for 30 minutes. Then, the member is 5 removed from the liquid, a put on a coarse mesh (such as a 14 mesh sieve) to allow dripping off of excess liquid.
  • a coarse mesh such as a 14 mesh sieve
  • test specimen is activated as described herein above, whilst the weight is monitored. Then, the test specimen is suspended or supported in a position such that the longest extension of the sample is essentially aligned with the gravity vector.
  • the sample can be supported by a support board or mesh arranged at an angle of close to 90° to the horizontal, or the sample can be suspended by straps or bands in a vertical position.
  • the tested material or member has passed this test, and is a liquid transport member according to the present invention.
  • the port region respectively the port region material is connected with a funnel and a tube as described in example A-1. Thereby, the lower end of the tube is left open i.e. not covered by a port region material.
  • the tube should be of sufficient length, i.e. up to 10m length may be required.
  • test material is very thin, or fragile, it can be appropriate to support it by a very open support structure (as e.g. a layer of open pore non- woven material) before connecting it with the funnel and the tube.
  • a very open support structure as e.g. a layer of open pore non- woven material
  • the funnel may be replaced by a smaller one (e.g. Catalog # 625 616 02 from Fisher Scientific in Nidderau, Germany). If the test specimen is too large size, a representative piece can be cut out so as to fit the funnel.
  • the testing liquid can be the transported liquid, but for ease of comparison, the testing liquid should be a solution 0.03% TRITON X-100, such as available from MERCK KGaA. Darmstadt, Germany, under the catalog number 1.08603, in destvetted or deionized water, thus resulting in a surface tension of 33mN/m, when measured according to the surface tension method as described further.
  • TRITON X-100 such as available from MERCK KGaA. Darmstadt, Germany
  • the part of the funnel with the port region is taken out of the liquid. If appropriate - but not necessarily - the funnel with the port region material should remain horizontally aligned.
  • the height Whilst slowly continuing to raise the port material above the reservoir, the height is monitored, and it is carefully observed through the funnel or through the port material itself (optionally aided by appropriate lighting) if air bubbles start to enter through the material into the inner of the funnel. At this point, the height above the reservoir is registered to be the bubble point height.
  • bubble point pressures exceeding about 50kPa an alternative determination can be used, such as commonly used for assessing bubble point pressures for membranes used in filtration systems.
  • the wetted membrane is separating two gas filled chambers, when one is set under an increased gas pressure (such as an air pressure), and the point is registered when the first air bubbles "break through".
  • an increased gas pressure such as an air pressure
  • the testing liquid can be the tranported liquid, but for ease of comparison, the testing liquid should a solution 0.03% TRITON X-100, such as available from MERCK KGaA, Darmsatdt, Germany, under the catalog number 1.08603, in destilled or deionized water, thus resulting in a surface tension of 33mN/m, when measured according to the surface tension method as described further.
  • a part of a port region under evaluation is connected to a vacuum pump connected by a tightly sealed tube/pipe (such as with PattexTM adhesive as described above). Care must be taken, that only a part of the port region is connected, and a further part of the region next to the one covered with the tube is still uncovered and in contact with ambient air.
  • a tightly sealed tube/pipe such as with PattexTM adhesive as described above.
  • the vacuum pump should allow to set various pressures p vac , increasing from atmospheric pressure P atm to about 100 kPa .
  • the pump is started to create a light vacuum, which is increased during the test in a stepwise operation.
  • the amount of pressure increase will depend on the desired accuracy, with typical values of 0.1 kPa providing acceptable results.
  • the flow will be monitored over time, and directly after the increase of ⁇ p, the flow will increase primarily because of removing gas from the tubing between the pump and the membrane. This flow will however, rather quickly level off, and upon establishing an equilibrium ⁇ p, the flow will essentially stop. This is typically reached after about 3 minutes.
  • This step change increase is continued up to the break through point, which can be observed by the gas flow not decreasing after the step change of the pressure, but remaining after reaching an equilibrium level essentially constant over time.
  • the pressure ⁇ p one step prior to this situation is the bpp of the liquid transport member.
  • the surface tension measurement is well known to the man skilled in the art, such as with a Tensiometer K10T from Kr ⁇ ss GmbH. Hamburg, Germany using the DuNouy ring method as described in the equipment instructions. After cleaning the glassware with iso-propanol and de-ionized water, it is dried at 105°C. The Platinum ring is heated over a Bunsen-bumer until red heat. A first reference measurement is taken to check the accuracy of the tensiometer. A suitable number of test replicates is taken to ensure consistency of the data. The resulting surface tension of the liquid as expressed in units of mN/m can be used to determine the adhesion tension values and surface energy parameter of the respective liquid/solid/gas systems. Destilled water will generally exhibit a surface tension value of 72mN/m, a 0.03% X-100 solution in water of 33mN/m.
  • the liquid transport member Before executing the test, the liquid transport member should be activated if necessary, as described in the above.
  • the test specimen is placed in a vertical position over a liquid reservoir, such as by being suspended from a holder, whereby the inlet port remains completely immersed in liquid in the reservoir
  • the outlet port is connected such as via a flexible tubing of 6 mm outer diameter to a vacuum pump - optionally 5 with a separator flask connected between the sample and the pump - and sealed in an air tight way as described in the above bubble point pressure method for a liquid transport member.
  • the vacuum suction pressure differential can be monitored and adjusted.
  • the lowermost point of the outlet port is adjusted to be at a height H 0 above o the liquid level in the reservoir.
  • the decrease of the weight of the liquid in the reservoir is monitored, preferably by positioning the reservoir on a 5 scale measuring the weight of the reservoir, and connecting the scale to a computing equipment. After an initial unsteady decrease (typically taking not more than about one minute), the weight decrease in the reservoir will become constant (i.e. showing a straight line in a graphical data presentation). This constant weight decrease over time is the flow rate (in g/s) of the liquid transport o member at suction of 0.9kPa and a height H 0 .
  • the corresponding flux rate of the liquid transport member at 0.9kPa suction and a height H 0 is calculated from the flow rate by dividing the flow rate with the average cross section of the liquid transport member along a flow path, expressed in g/s/cm 2 . 5 Care should be take, that the reservoir is large enough so that the fluid level in the reservoir does not change by more than 1 mm.
  • the effective permeability of the liquid transport member can be calculated by dividing the flux rate by the average length along a flow path and the driving pressure difference (0.9kPa).
  • test can be carried out with a suitable test fluid representing the transport fluid, such as with Jayco SynUrine as available from Jayco Pharmaceuticals Company of Camp Hill, Pennsylvania, and can be operated under controlled laboratory conditions of about 23 +/- 2°C and at 50 +/-10% relative humidity.
  • a suitable test fluid representing the transport fluid such as with Jayco SynUrine as available from Jayco Pharmaceuticals Company of Camp Hill, Pennsylvania, and can be operated under controlled laboratory conditions of about 23 +/- 2°C and at 50 +/-10% relative humidity.
  • suitable test fluid representing the transport fluid
  • Jayco SynUrine as available from Jayco Pharmaceuticals Company of Camp Hill, Pennsylvania
  • polymeric foam materials such as disclosed in US-A-5.563.179 or US-A- 5.387.207, it has been found more useful to operate the test at an elevated temperature of 31 °C, and by using de-ionized water as test fluid.
  • the present Permeability Test provides a measure for permeability for two special conditions: Either the permeability can be measured for a wide range of porous materials (such as non-wovens made of synthetic fibres, or cellulosic structures) at 100% saturation, or for materials, which reach different degrees of saturation with a proportional change in caliper without being filled with air (respectively the outside vapour phase), such as the collapsible polymeric foams, for which the permeability at varying degrees of saturation can readily be measured at various thicknesses.
  • porous materials such as non-wovens made of synthetic fibres, or cellulosic structures
  • the test can be executed in two modifications, the first referring to the transplanar permeability (i.e. the direction of flow is essentially along the thickness dimension of the material), the second being the in-plane permeability (i.e. the direction of flow being in the x-y-direction of the material).
  • Figure 19 is a schematic diagram of the overall equipment and - as an insert diagram - a partly exploded cross-sectional, not to scale view of the sample cell.
  • the test set-up comprises a generally circular or cylindrical sample cell (19120), having an upper (19121) and lower (19122) part. The distance of these parts can be measured and hence adjusted by means of each three circumferentially arranged caliper gauges (19145) and adjustment screws (19140). Further, the equipment comprises several fluid reservoirs (19150, 19154, 19156) including a height adjustment (19170) for the inlet reservoir (19150) as well as tubings (19180), quick release fittings (19189) for connecting the sample cell with the rest of the equipment, further valves (19182, 19184, 19186, 19188).
  • the differential pressure transducer (19197) is connected via tubing (19180) to the upper pressure detection point (19194) and to the lower pressure detection point (19196).
  • a Computer device (19190) for control of valves is further connected via connections (19199) to differential pressure transducer (19197), temperature probe (19192), and weight scale load cell (19198).
  • the circular sample (19110) having a diameter of 1 in (about 2.54 cm) is placed in between two porous screens (19135) inside the sample cell (19120), which is made of two 1 in (2.54 cm) inner diameter cylindrical pieces (19121 , 19122) attached via the inlet connection (19132) to the inlet reservoir (19150) and via the outlet connection (19133) to the outlet reservoir (19154) by flexible tubing (19180), such as tygon tubing. Closed cell foam gaskets (191 15) provide leakage protection around the sides of the sample.
  • the test sample (19110) is compressed to the caliper corresponding to the desired wet compression, which is set to 0.2 psi (about 1 .4 kPa) unless otherwise mentioned.
  • Liquid is allowed to flow through the sample (191 10) to achieve steady state flow.
  • volumetric flow rate and pressure drop are recorded as a function of time using a load cell (19198) and the differential pressure transducer (19197).
  • the experiment can be performed at any pressure head up to 80 cm water (about 7.8 kPa), which can be adjusted by the height adjusting device (19170). From these measurements, the flow rate at. different pressures for the sample can be determined.
  • the equipment is commercially available as a liquid Permeameter such as supplied by Porous Materials, Ine, Ithaca, New York, US under the designation PMI Liquid Permeameter, such as further described in respective user manual of 2/97, and modified according to the present description.
  • This equipment includes two Stainless Steel Frits as porous screens (19135), also specified in said brochure.
  • the equipment consists of the sample cell (19120), inlet reservoir (19150), outlet reservoir (19154), and waste reservoir (19156) and respective filling and emptying valves and connections, an electronic scale, and a computerized monitoring and valve control unit (19190).
  • the gasket material (191 15) is a Closed Cell Neoprene Sponge SNC-1 (Soft), such as supplied by Netheriand Rubber Company, Cincinnati, Ohio, US.
  • Soft a Closed Cell Neoprene Sponge SNC-1
  • a set of materials with varying thickness in steps of 1/16" (about 0.159 cm) should be available to cover the range from 1/16" -1/2" (about 0.159 cm to about 1.27 cm) thickness.
  • test sample(s) is then executed by the following steps: 1) Preparation of the test sample(s):
  • a preparatory test it is determined, if one or more layers of the test sample are required, wherein the test as outlined below is run at the lowest and highest pressure. The number of layers is then adjusted so as to maintain the flow rate during the test between 0.5 cm 3 /seconds at the lowest pressure drop and 15 cm 3 /second at the highest pressure drop. The flow rate for the sample should be less than the flow rate for the blank at the same pressure drop. If the sample flow rate exceeds that of the blank for a given pressure drop, more layers should be added to decrease the flow rate.
  • Sample size Samples are cut to 1" (about 2.54 cm) diameter, by using an arch punch, such as supplied by McMaster-Carr Supply Company, Cleveland, OH, US. If samples have too little internal strength or integrity to maintain their structure during the required manipulation, a conventional low basis weight support means can be added, such as a PET scrim or net.
  • At least two samples are precut. Then, one of these is saturated in deionized water at the temperature the experiment is to be performed (70° F, (31° C) unless otherwise noted).
  • the caliper of the wet sample is measured (if necessary after a stabilization time of 30 seconds) under the desired compression pressure for which the experiment will be run by using a conventional caliper gauge (such as supplied by AMES, Waltham, MASS, US) having a pressure foot diameter of 1 1/8 " (about 2.86 cm), exerting a pressure of 0.2 psi (about 1.4 kPa) on the sample (191 10), unless otherwise desired.
  • gasketing foam (19115) is between 150 and 200% of the thickness of the wet sample (note that a combination of varying thicknesses of gasket material may be needed to achieve the overall desired thickness).
  • the gasket material (19115) is cut to a circular size of 3" in diameter, and a 1 inch (2.54 cm) hole is cut into the center by using the arch punch.
  • the sample should be cut such that the required diameter is taken in the wet stage. This can also be assessed in this preparatory test, with monitoring of the respective dimensions. If these change such that either a gap is formed, or the sample forms wrinkles which would prevent it from smoothly contacting the porous screens or frits, the cut diameter should be adjusted accordingly.
  • test sample (19110) is placed inside the hole in the gasket foam (19115), and the composite is placed on top of the bottom half of the sample cell, ensuring that the sample is in flat, smooth contact with the screen (19135), and no gaps are formed at the sides.
  • test cell (19121) The top of the test cell (19121) is laid flat on the lab bench (or another horizontal plane) and all three caliper gauges (19145) mounted thereon are zeroed.
  • the top of the test cell (19121) is then placed onto the bottom part (19122) such that the gasket material(19115) with the test sample (19110) lays in between the two parts.
  • the top and bottom part are then tightened by the fixation screws (19140), such that the three caliper gauges are adjusted to the same value as measured for the wet sample under the respective pressure in the above.
  • the inlet liquid reservoir (19150) is set to the required height and the test is started on the computerized unit (19190). 5) Then, the sample cell (19120) is positioned into the permeameter unit with Quick Disconnect fittings (19189).
  • the sample cell (19120) is filled by opening the vent valve (19188) and the bottom fill valves (19184, 19186). During this step, care must be taken to remove air bubbles from the system, which can be achieved by turning the sample cell vertically, forcing air bubbles - if present - to exit the permeameter through the drain.
  • the liquid outlet flow is automatically diverted from the waste reservoir (19156) to the outlet reservoir (19154), and pressure drop, and temperature are monitored as a function of time for several minutes.
  • the computerized unit provides the recorded data (in numeric and/or graphical form). If desired, the same test sample can be used to measure the permeability at varying pressure heads, with thereby increasing the pressure from run to run.
  • the equipment should be cleaned every two weeks, and calibrated at least once per week, especially the frits, the load cell, the thermocouple and the pressure transducer, thereby following the instructions of the equipment supplier.
  • the differential pressure is recorded via the differential pressue transducer connected to the pressure probes measurement points (19194, 19196) in the top and bottom part of the sample cell. Since there may be other flow resistances within the chamber adding to the pressure that is recorded, each experiment must be corrected by a blank run. A blank run should be done at 10, 20, 30, 40, 50, 60, 70, 80 cm requested pressure, each day.
  • the permeameter will output a Mean Test Pressure for each experiment and also an average flow rate.
  • the flow rate is recorded as Blank Corrected Pressure by the computerized unit (19190), which is further correcting the Mean Test Pressure (Actual Pressure) at each height recorded pressure differentials to result in the Corrected Pressure.
  • This Corrected Pressure is the DP that should be used in the permeability equation below.
  • Permeability can then be calculated at each requested pressure and all permeabilities should be averaged to determine the k for the material being tested.
  • the measuring of the in-plane permeability under the same conditions as the above described transplanar permeability can be achieved by modifying the above equipment such as schematically depicted in Figures 20A and 20B showing the partly exploded, not to scale view of the sample cell only.
  • Equivalent elements are denoted equivalently, such that the sample cell of Figure 20 is denoted (20210), correlating to the numeral (19110) of Figure 19, and so on.
  • the transplanar simplified sample cell (19120) of Figure 19 is replaced by the in-plane simplified cell (20220), which is designed so that liquid can flow only in one direction (either machine direction or cross direction depending on how the sample is placed in the cell). Care should be taken to minimize channeling of liquid along the walls (wall effects), since this can erroneously give high permeability reading.
  • the test procedure is then executed quite analogous to the transplanar test.
  • the sample cell (20220) is designed to be positioned into the equipment essentially as described for the sample cell (20120) in the above transplanar test, except that the filling tube is directed to the inlet connection (20232) the bottom of the cell (20220).
  • Figure 20A shows a partly exploded view of the sample cell
  • Figure 20B a cross-sectional view through the sample level.
  • the test cell (20220) is made up of two pieces: a bottom piece (20225) which is like a rectangular box with flanges, and a top piece (20223) that fits inside the bottom piece (20225) and has flanges as well.
  • the test sample is cut to the size of 2" in x 2"in (about 5.1 cm by 5.1 cm) and is placed into the bottom piece.
  • the top piece (20223) of the sample chamber is then placed into the bottom piece (20225) and sits on the test sample (20210).
  • An incompressible neoprene rubber seal (20224) is attached to the upper piece (20223) to provide tight sealing.
  • the test liquid flows from the inlet reservoir to the sample space via Tygon tubing and the inlet connection (20232) further through the outlet connection (20233) to the outlet reservoir.
  • the sample is kept at the desired test temperature by the heating device (20226), whereby thermostated water is pumped through the heating chamber (20227).
  • the gap in the test cell is set at the caliper corresponding to the desired wet compression, normally 0.2 psi ( about 1.4 kPa).
  • Shims (20216) ranging in size from 0.1 mm to 20.0 mm are used to set the correct caliper, optionally using combinations of several shims.
  • test cell (20220) is rotated 90° (sample is vertical) and the test liquid allowed to enter slowly from the bottom. This is necessary to ensure that all the air is driven out from the sample and the inlet/outlet connections (20232/20233).
  • the test cell (20220) is rotated back to its original position so as to make the sample (20210) horizontal.
  • the subsequent procedure is the same as that described earlier for transplanar permeability, i.e. the inlet reservoir is placed at the desired height, the flow is allowed to equilibrate, and flow rate and pressure drop are measured. Permeability is calculated using Darcy's law. This procedure is repeated for higher pressures as well.
  • Optical determination of pore size is especially used for thin layers of porous system by using standard image analysis procedures know to the skilled artisan.
  • a thin layer of the sample material is prepared by either slicing a thick sample into thinner sheets or if the sample itself is thin by using it directly.
  • the term "thin” refers to achieving a sample caliper low enough to allow a clear cross-section image under the microscope. Typical sample calipers are below 200 ⁇ m.
  • a microscopic image is obtained via a video microscope using the appropriate magnification. Best results are obtained if about 10 to 100 pores are visible on said image.
  • the image is then digitized by a standard image analysis package such as OPTIMAS by BioScan Co ⁇ . which runs under Windows 95 on a typical IBM compatible PC.
  • Frame grabber of sufficient pixel resolution should be used to obtain good results.
  • the image is converted to a binary image using an appropriate threshold level such that the pores visable on the image are marked as object areas in white and the rest remains black. Automatic threshold setting procedures such as available under OPTIMAS can be used.
  • the areas of the individual pores (objects) are determined. OPTIMAS offers fully automatic determination of the areas.
  • the average pore size can then be determined from the pore size distribution using standard statistical rules. For materials that have a not very uniform pore size it is recommended to use at least 3 samples for the determination.
  • the Teabag Centrifuge Capacity test measures the Teabag Centrifuge Capacity values, which are a measure of the retention of liquids in the absorbent materials.
  • the absorbent material is placed within a "teabag", immersed in a 0.9% by weight sodium chloride solution for 20 minutes, and then centrifuged for 3 minutes.
  • the ratio of the retained liquid weight to the initial weight of the dry material is the absorptive capacity of the absorbent material.
  • Two liters of 0.9% by weight sodium chloride in distilled water is poured into a tray having dimensions 24 cm x 30 cm x 5 cm. The liquid filling height should be about 3 cm.
  • the teabag pouch has dimensions 6.5 cm x 6.5 cm and is available from Teekanne in D ⁇ sseldorf, Germany.
  • the pouch is heat sealable with a standard kitchen plastic bag sealing device (e.g. VACUPACK2 PLUS from Krups, Germany).
  • the teabag is opened by carefully cutting it partially, and is then weighed.
  • 0.005g is placed in the teabag.
  • the teabag is then closed with a heat sealer. This is called the sample teabag.
  • An empty teabag is sealed and used as a blank.
  • the sample teabag and the blank teabag are then laid on the surface of the saline solution, and submerged for about 5 seconds using a spatula to allow complete wetting (the teabags will float on the surface of the saline solution but are then completely wetted). The timer is started immediately.
  • the sample teabag and the blank teabag are removed from the saline solution, and placed in a Bauknecht WS130, Bosch 772 NZK096 or equivalent centrifuge (230 mm diameter), so that each bag sticks to the outer wall of the centrifuge basket.
  • the centrifuge lid is closed, the centrifuge is started, and the speed increased quickly to 1 ,400 ⁇ m. Once the centrifuge has been stabilised at 1 ,400 ⁇ m the timer is started. After 3 minutes, the centrifuge is stopped.
  • TCC Teabag Centrifuge Capacity
  • TCC [(sample teabag weight after centrifuging) - (blank teabag weight after centrifuging) - (dry absorbent material weight)] ⁇ (dry absorbent material weight).
  • specific parts of the structures or the total absorbent articles can be measured, such as "sectional” cut outs, i.e. looking at parts of the structure or the total article, whereby the cutting is done across the full width of the article at determined points of the longitudinal axis of the article.
  • the definition of the "crotch region” as described above allows to determine the "crotch region capacity”.
  • Other cut-outs can be used to determine a "basis capacity” (i.e. the amount of capacity contained in a unit area of the specific region of the article. Depending on the size of the unit area (preferably 2 cm by 2 cm) the defines how much averaging is taking place - naturally, the smaller the size, the less averaging will occur.
  • the test specimen is a liquid handling member according to the present invention.
  • the liquid handling member should be configured to resemble as closely as possible its in use configuration. If the liquid handling member is part of the device for handling body liquids, those parts of the device which do not contribute to the performance of the liquid handling member may be removed prior to testing the liquid handling member. It is, however, also possible to test a device for handling body liquids in its entirety.
  • the total absorbent capacity of the specimen is determined via the demand absorbency test defined herein.
  • the specimen which is now filled with liquid up to its total absorbent capacity is now placed on the glass frit of the capillary sorption test defined herein which has been set at 0 cm hydrohead.
  • the experimental set up for this test comprises the set up for the capillary sorption test defined herein in combination with a volume measurement device which is installed such that it is capable of measuring the dimensions of the specimen when the specimen is placed on the glass frit of the capillary so ⁇ tion experimental set up.
  • the volume measurement device may consist of a caliper (z - direction) measurement device, in combination with two devices which measure the expansion of the test specimen in the two dimensions (x -, and y - direction) parallel to the surface of the glass frit. Since the two major surfaces of the glass frit in the capillary so ⁇ tion experimental setup are oriented horizontally, the caliper measurement device in this test measures the vertical expansion of the test specimen whereas the other two measurement devices measure the horizontal expansion of the test specimen. If, for example, the test specimen is substantially rectangular simple mechanic devices for manual determination of length may be used to determine the dimensions of the test specimen.
  • the geometry of the test specimen is more complex, contraction and expansion of the test specimen may be recorded for example on video tape which allows for exact analysis of expansion and contraction of the test specimen during the test.
  • Suitable methods for the determination of each of the dimensions are well known in the art. If such method requires that the test specimen is put under a confining pressure, the confining pressure should be chosen low enough such that the respective dimension of the test specimen remains substantially unchanged. Furthermore, it is important that a dimension of the test specimen is measured over a surface area which is at least 20 percent of the respective surface area of the test specimen such that the measurement is representative of the dimension.
  • the total absorbent capacity of the test specimen is determined via the demand absorbency test defined herein.
  • the capillary suction is decreased to zero pressure such that the test specimen will take up liquid again until the specimen is filled up to its total capacity.
  • the expansion factor for each dimension is determined by dividing the respective dimension of the test specimen at the end of this test phase by its respective dimension at the beginning of this test phase. Often, the value of each expansion factor will be at least 1.
  • the volume expansion factor is determined by dividing the volume at the end of this test phase by the volume at the beginning of this test phase.
  • the liquid capacity at the end of the cycle is divided by the total absorbent capacity of the test specimen as determined by the demand absorbency test prior to this test to obtain the capacity decrease factor.
  • the above measurement cycle of second step and third step may be repeated in order to examine the longtime behavior of the test specimen.
  • the respective contraction factors, expansion factors, and capacity decrease factors are then denoted together with the number of their respective test cycle.
  • the temperature of the liquid and the environment for the test should reflect in-use conditions of the member. Typical temperature for use in baby diapers are

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  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Veterinary Medicine (AREA)
  • Thermal Sciences (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Vascular Medicine (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Epidemiology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Chemical & Material Sciences (AREA)
  • Biomedical Technology (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Surgery (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Orthopedics, Nursing, And Contraception (AREA)
  • Absorbent Articles And Supports Therefor (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Porous Artificial Stone Or Porous Ceramic Products (AREA)
  • Laminated Bodies (AREA)

Abstract

L'invention concerne un élément de transport de liquides présentant des propriétés de traitement de liquides sensiblement améliorées. Cet élément comporte au moins une zone centrale complètement entourée par une zone périphérique et comportant au moins une zone d'orifice. Dans cet élément, le produit de la pression de point de bulle par la perméabilité de la zone centrale est plus élevé que la moitié du produit de la porosité de l'élément par la tension superficielle du liquide transporté.
PCT/US1999/014633 1998-06-29 1999-06-29 Element de transport de liquides pourvu de zones centrales a permeabilite elevee et de zones d'orifice a pression de seuil elevee WO2000000136A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
AU48406/99A AU4840699A (en) 1998-06-29 1999-06-29 Liquid transport member having high permeability bulk regions and high thresholdpressure port regions
CA002336022A CA2336022A1 (fr) 1998-06-29 1999-06-29 Element de transport de liquides pourvu de zones centrales a permeabilite elevee et de zones d'orifice a pression de seuil elevee
EP99932008A EP1091712A1 (fr) 1998-06-29 1999-06-29 Element de transport de liquides pourvu de zones centrales a permeabilite elevee et de zones d'orifice a pression de seuil elevee
JP2000556722A JP2002522250A (ja) 1998-06-29 1999-06-29 高い透過性のバルク領域と高い限界圧力のポート領域とを有する液体輸送部材

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
PCT/US1998/013523 WO2000000131A1 (fr) 1998-06-29 1998-06-29 Element de transport de liquide possedant des regions de materiau en vrac a permeabilite elevee et des regions d'entree a pression de seuil elevee
USPCT/US98/13523 1998-06-29

Publications (1)

Publication Number Publication Date
WO2000000136A1 true WO2000000136A1 (fr) 2000-01-06

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PCT/US1998/013523 WO2000000131A1 (fr) 1998-06-29 1998-06-29 Element de transport de liquide possedant des regions de materiau en vrac a permeabilite elevee et des regions d'entree a pression de seuil elevee
PCT/US1999/014633 WO2000000136A1 (fr) 1998-06-29 1999-06-29 Element de transport de liquides pourvu de zones centrales a permeabilite elevee et de zones d'orifice a pression de seuil elevee

Family Applications Before (1)

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PCT/US1998/013523 WO2000000131A1 (fr) 1998-06-29 1998-06-29 Element de transport de liquide possedant des regions de materiau en vrac a permeabilite elevee et des regions d'entree a pression de seuil elevee

Country Status (7)

Country Link
EP (1) EP1091712A1 (fr)
JP (1) JP2002522250A (fr)
AU (2) AU8378298A (fr)
CA (1) CA2336022A1 (fr)
PE (1) PE20000791A1 (fr)
TW (1) TW416845B (fr)
WO (2) WO2000000131A1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6659992B1 (en) 1998-06-29 2003-12-09 The Procter & Gamble Company Absorbent article instanteously storing liquid in a predefined pattern
US6764476B1 (en) 1998-06-29 2004-07-20 The Procter & Gamble Company Absorbent article comprising a liquid handling member that rapidly distributes acquired liquid
US6849065B2 (en) 1999-12-23 2005-02-01 The Procter & Gamble Company Liquid removal system having improved dryness of the user facing surface
US6932797B2 (en) 1999-12-23 2005-08-23 The Procter & Gamble Company Liquid removal system which is compressible in the longitudinal and/or in the transverse direction
US10729592B2 (en) 2015-11-04 2020-08-04 The Procter & Gamble Company Absorbent structure
US10729600B2 (en) 2015-06-30 2020-08-04 The Procter & Gamble Company Absorbent structure
US11020289B2 (en) 2015-11-04 2021-06-01 The Procter & Gamble Company Absorbent structure
US11173078B2 (en) 2015-11-04 2021-11-16 The Procter & Gamble Company Absorbent structure
US11266542B2 (en) 2017-11-06 2022-03-08 The Procter & Gamble Company Absorbent article with conforming features
US11376168B2 (en) 2015-11-04 2022-07-05 The Procter & Gamble Company Absorbent article with absorbent structure having anisotropic rigidity

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Publication number Priority date Publication date Assignee Title
RU2124142C1 (ru) 1998-03-25 1998-12-27 Орлов Игорь Сергеевич Ветроэнергетическая установка
US7569742B2 (en) 2005-09-07 2009-08-04 Tyco Healthcare Group Lp Self contained wound dressing with micropump
JP5212940B2 (ja) * 2008-07-17 2013-06-19 光敏 栢島 バロメトリックサイホンによる冷暖房発電蒸留装置
ES2731463T3 (es) 2011-07-14 2019-11-15 Smith & Nephew Apósito para heridas y método de tratamiento
ES2769298T3 (es) 2012-05-23 2020-06-25 Smith & Nephew Aparatos para terapia de heridas por presión negativa
DK2879636T3 (da) 2012-08-01 2017-06-19 Smith & Nephew Sårbandage
EP3406231B1 (fr) 2012-08-01 2022-04-13 Smith & Nephew plc Pansement pour plaies et procédé de traitement
WO2015193257A1 (fr) 2014-06-18 2015-12-23 Smith & Nephew Plc Pansement et procédé de traitement
GB2555584B (en) 2016-10-28 2020-05-27 Smith & Nephew Multi-layered wound dressing and method of manufacture

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EP0365565A1 (fr) 1987-07-01 1990-05-02 Novapharm Research Pty. Ltd. Composition germicide
EP0439890A1 (fr) 1990-02-01 1991-08-07 Dennis Hurley Système de drainage des terrains
US5082723A (en) 1989-09-27 1992-01-21 Kimberly-Clark Corporation Osmotically enhanced absorbent structures
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US5387207A (en) 1991-08-12 1995-02-07 The Procter & Gamble Company Thin-unit-wet absorbent foam materials for aqueous body fluids and process for making same
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US5563179A (en) 1995-01-10 1996-10-08 The Proctor & Gamble Company Absorbent foams made from high internal phase emulsions useful for acquiring and distributing aqueous fluids
EP0773058A1 (fr) 1995-11-10 1997-05-14 Kabushiki Kaisha Toyota Chuo Kenkyusho Membrane pour la filtration de liquides organiques oléophiles, procédé pour sa fabrication et procédé pour la filtration de liquides organiques oléophiles
EP0780148A1 (fr) 1995-12-20 1997-06-25 Corning Incorporated Dispositif de filtration ou de membrane avec des parois avec épaisseur augmentante
WO1997035656A1 (fr) 1996-03-22 1997-10-02 Alfa Laval Ab Unite de filtre
EP0810078A1 (fr) 1996-05-28 1997-12-03 The Procter & Gamble Company Procédé pour la fabrication de matériaux ayant une distribution de fluide améliorée
WO1997047375A1 (fr) 1996-06-10 1997-12-18 Usf Rossmark Waterbehandeling B.V. Systeme de filtre membranaire
US5728292A (en) 1993-11-11 1998-03-17 Nissan Motor Co., Ltd. Filter for in-tank fuel pump
US5733581A (en) 1995-05-02 1998-03-31 Memtec America Corporation Apparatus for making melt-blown filtration media having integrally co-located support and filtration fibers
WO1998022068A1 (fr) * 1996-11-22 1998-05-28 Kimberly-Clark Worldwide, Inc. Matiere anti-fuite heterogene destinee a des articles absorbants
WO1998022063A1 (fr) * 1996-11-18 1998-05-28 The Procter & Gamble Company Article absorbant presentant un element pompant les liquides

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US4820293A (en) 1981-12-11 1989-04-11 Kamme Carl G Absorbent body with semipermeable membrane
US4676785A (en) * 1985-10-21 1987-06-30 Battista Orlando A Liquid retaining absorbent structure
EP0365565A1 (fr) 1987-07-01 1990-05-02 Novapharm Research Pty. Ltd. Composition germicide
US5082723A (en) 1989-09-27 1992-01-21 Kimberly-Clark Corporation Osmotically enhanced absorbent structures
US5108383A (en) 1989-12-08 1992-04-28 Allied-Signal Inc. Membranes for absorbent packets
EP0439890A1 (fr) 1990-02-01 1991-08-07 Dennis Hurley Système de drainage des terrains
US5387207A (en) 1991-08-12 1995-02-07 The Procter & Gamble Company Thin-unit-wet absorbent foam materials for aqueous body fluids and process for making same
US5728292A (en) 1993-11-11 1998-03-17 Nissan Motor Co., Ltd. Filter for in-tank fuel pump
WO1995028139A1 (fr) * 1994-04-15 1995-10-26 Silber Arthur L Structure de tampon ne provoquant pas de reaction toxique
US5563179A (en) 1995-01-10 1996-10-08 The Proctor & Gamble Company Absorbent foams made from high internal phase emulsions useful for acquiring and distributing aqueous fluids
US5733581A (en) 1995-05-02 1998-03-31 Memtec America Corporation Apparatus for making melt-blown filtration media having integrally co-located support and filtration fibers
EP0773058A1 (fr) 1995-11-10 1997-05-14 Kabushiki Kaisha Toyota Chuo Kenkyusho Membrane pour la filtration de liquides organiques oléophiles, procédé pour sa fabrication et procédé pour la filtration de liquides organiques oléophiles
EP0780148A1 (fr) 1995-12-20 1997-06-25 Corning Incorporated Dispositif de filtration ou de membrane avec des parois avec épaisseur augmentante
WO1997035656A1 (fr) 1996-03-22 1997-10-02 Alfa Laval Ab Unite de filtre
EP0810078A1 (fr) 1996-05-28 1997-12-03 The Procter & Gamble Company Procédé pour la fabrication de matériaux ayant une distribution de fluide améliorée
WO1997047375A1 (fr) 1996-06-10 1997-12-18 Usf Rossmark Waterbehandeling B.V. Systeme de filtre membranaire
WO1998022063A1 (fr) * 1996-11-18 1998-05-28 The Procter & Gamble Company Article absorbant presentant un element pompant les liquides
WO1998022068A1 (fr) * 1996-11-22 1998-05-28 Kimberly-Clark Worldwide, Inc. Matiere anti-fuite heterogene destinee a des articles absorbants

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6659992B1 (en) 1998-06-29 2003-12-09 The Procter & Gamble Company Absorbent article instanteously storing liquid in a predefined pattern
US6764476B1 (en) 1998-06-29 2004-07-20 The Procter & Gamble Company Absorbent article comprising a liquid handling member that rapidly distributes acquired liquid
US6849065B2 (en) 1999-12-23 2005-02-01 The Procter & Gamble Company Liquid removal system having improved dryness of the user facing surface
US6932797B2 (en) 1999-12-23 2005-08-23 The Procter & Gamble Company Liquid removal system which is compressible in the longitudinal and/or in the transverse direction
US11957556B2 (en) 2015-06-30 2024-04-16 The Procter & Gamble Company Absorbent structure
US10729600B2 (en) 2015-06-30 2020-08-04 The Procter & Gamble Company Absorbent structure
US11020289B2 (en) 2015-11-04 2021-06-01 The Procter & Gamble Company Absorbent structure
US11173078B2 (en) 2015-11-04 2021-11-16 The Procter & Gamble Company Absorbent structure
US11376168B2 (en) 2015-11-04 2022-07-05 The Procter & Gamble Company Absorbent article with absorbent structure having anisotropic rigidity
US10729592B2 (en) 2015-11-04 2020-08-04 The Procter & Gamble Company Absorbent structure
US11266542B2 (en) 2017-11-06 2022-03-08 The Procter & Gamble Company Absorbent article with conforming features
US11857397B2 (en) 2017-11-06 2024-01-02 The Procter And Gamble Company Absorbent article with conforming features
US11864982B2 (en) 2017-11-06 2024-01-09 The Procter And Gamble Company Absorbent article with conforming features
US11890171B2 (en) 2017-11-06 2024-02-06 The Procter And Gamble Company Absorbent article with conforming features

Also Published As

Publication number Publication date
AU8378298A (en) 2000-01-17
PE20000791A1 (es) 2000-11-04
TW416845B (en) 2001-01-01
CA2336022A1 (fr) 2000-01-06
AU4840699A (en) 2000-01-17
EP1091712A1 (fr) 2001-04-18
WO2000000131A1 (fr) 2000-01-06
JP2002522250A (ja) 2002-07-23

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