Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Low-density, open-cell, soft, flexible, thermoplastic, absorbent foam and method of making foam

a technology of absorbent foam and low density, applied in the field of low density, open-cell, thermoplastic, absorbent foam, can solve the problems of difficult to achieve low densities with absorbency, difficult to produce foam, and thin membranes between cells

Inactive Publication Date: 2006-02-09
KIMBERLY-CLARK WORLDWIDE INC
View PDF99 Cites 66 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0020] With the foregoing in mind, it is a feature and advantage of the invention to provide a low-density, open-cell, thermoplastic, absorbent foam that is soft and flexible, and a method of making such a foam in which the open-cell content can be controlled.
to provide a low-density, open-cell, thermoplastic, absorbent foam that is soft and flexible, and a method of making such a foam in which the open-cell content can be controlled.

Problems solved by technology

All of these foam qualities in a single foam would be particularly desirable in a number of absorbent product applications; however, it is difficult to produce such foam.
Foaming soft, flexible polymers, such as thermoplastic elastomers, to low densities with absorbency is difficult to achieve.
When cells expand, membranes between cells thin and can become unstable, rupture, and can thereby create porous connections between cells.
Although plasticizing agents act as softeners, the addition of plasticizing agents makes foaming to low densities even more difficult.
In particular, plasticizing agents typically lower polymer melt viscosities and lead to increasing melt drainage that causes foaming difficulties with cell collapse.
However, such glycerol fatty acids are unable to provide sufficient wettability.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Low-density, open-cell, soft, flexible, thermoplastic, absorbent foam and method of making foam
  • Low-density, open-cell, soft, flexible, thermoplastic, absorbent foam and method of making foam
  • Low-density, open-cell, soft, flexible, thermoplastic, absorbent foam and method of making foam

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0108] Foam polymer formulas were made from blends of Dow STYRON® 685D polystyrene pelletized resin and KRATON® G1657 styrene-ethylene-butylene-styrene (SEBS) block copolymer pelletized thermoplastic elastomer resin. Low molecular weight polyethylene wax (Eastman EPOLENE® C-10) was added to certain samples to plasticize the foam polymer formula. A surfactant, Dow-Corning 193, available from Dow-Corning Company in Midland, Mich., U.S.A., was added to certain samples to improve wettability. A nucleating agent, CLOISITE® 20A, was also added at 5%, by weight, to the foam polymer formula. All foams were extruded using a 27-mm Leistritz co-rotating twin screw extruder, available from American Leistritz Extruder Corporation in Somerville, N.J., U.S.A., equipped for direct injection of carbon dioxide gas. The foam polymer formulas were heated to about 200 degrees Celsius in the extruder and subsequently foamed using carbon dioxide (added at 6%, by weight, of the foam polymer formula) as a b...

example 2

[0117] This example illustrates the importance of surfactant structure to enable the production of low-density foams from a blend of polystyrene with soft, flexible polymers. The foam polymer formula in this example included 50.0 parts of Dow STYRON® 685D polystyrene and 45.2 parts of KRATON® G1657 SEBS, and 4.8 parts CLOISITE 20A nanoclay. Foam extrusion method was the same as Example 1. Samples of the foam polymer formula with various surfactants, and levels of surfactant, and results of these samples are shown in Table 3.

TABLE 3Foaming Soft, Flexible Polymers With Various SurfactantsSurfactantAmount(parts per100 partsFoamOpen-of foamDensity,LiquidCellpolymerlb / ft3PenetrationContentSampleSurfactant Descriptionformula)(g / cm3)into Foam(%)1bNo Surfactant057 (0.91)No242bClariant HOSTASTAT2.7 7 (0.11)Yes84HS-1(sulfuric acid head C12-C18saturated tail)3bDow Corning 1934.613 (0.21)Yes76(ethoxylated siliconepolymer)4bCognis EMEREST 26502.710 (0.16)No82(PEG 400 headC12 saturated tail)5bC...

example 3

[0120] This example illustrates the effect of multiple surfactants in comparison to single surfactants in the foam polymer formula. Table 4 illustrates the results of adding various dosages of surfactants and surfactant mixtures to a polymer blend of 54.45 parts of Dow STYRON® 685D polystyrene, 44.55 parts of KRATON® G1657 with 1 part of MISTRON® VAPOR talc, used as a nucleant, and available from Luzenac America, Inc., of Englewood, Colo., U.S.A. The surfactants utilized were: HOSTASTAT® HS-1, an alkyl sulfonate available from Clariant Corporation in Winchester, Va., U.S.A.; MMF 184 SW, an ethoxylated siloxane available from Siltech LLC in Dacula, Ga., U.S.A.; and MASIL® SF-19, an ethoxylated siloxane available from BASF Corporation in Mount Olive, N.J., U.S.A. Foam extrusion method was the same as Example 1 except that the maximum extrusion temperature utilized was 195 degrees Celsius and carbon dioxide addition rate was about 15%, by weight of the foam polymer.

[0121] In Table 4, ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
densityaaaaaaaaaa
wicking heightaaaaaaaaaa
densityaaaaaaaaaa
Login to View More

Abstract

A soft, flexible, low-density, open-cell, thermoplastic, absorbent foam formed from a foam polymer formula including a balanced amount of a plasticizing agent and a surfactant in combination with a base resin. Thermoplastic elastomers can be added to the foam polymer formula to improve softness, flexibility, elasticity, and resiliency of the resulting foam. The surfactant may be either a single surfactant or a multi-surfactant system. The foam possesses a number of qualities, such as softness and strength, which render the foam particularly suitable for use in a variety of personal care products, medical products, and the like.

Description

[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10 / 729,881, filed 05 Dec. 2003, the disclosure of which is incorporated by reference.BACKGROUND OF THE INVENTION [0002] This invention is directed to a low-density, open-cell, thermoplastic, absorbent foam that is soft and flexible. The foam can be made with balanced amounts of one or more surfactants and a plasticizing agent in a foam polymer formula. Thermoplastic elastomers can be added to the foam polymer formula to improve softness, flexibility, elasticity and resiliency. Some thermoplastic elastomers function as plasticizing agents. [0003] Thermoplastic absorbent foam is made of polymer(s) that can be heated, formed and cooled repeatedly, typically commercially using a continuous plastic extrusion process. Thermoplastic absorbent foam can be used to produce personal care products including, but not limited to, absorbent articles such as disposable diapers, baby wipes, training pants, child-ca...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): C08J9/00A61F13/15A61L15/22A61L15/42A61L15/48
CPCA61F2013/530817A61L15/225A61L15/425C08J2207/12C08J2201/03C08J2205/05A61L15/48C08J9/00C08J9/22
Inventor KRUEGER, JEFFREY JENNINGSRADWANSKI, FRED ROBERTREICHMANN, MARK G.ELLIKER, PETER ROBERTYAHIAOUI, ALIRICHARD, RENETTE E.THOMAS, OOMMAN PAINUMMOOTTILCOLMAN, CHARLES W.BAKER, ANDREW T.DAY, JENNY L.ZHANG, XIAOMINRANGANATHAN, SRIDHARCOLOMBO, EDWARD A.WALDROUP, DONALD E.
Owner KIMBERLY-CLARK WORLDWIDE INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products