Classifications

• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/732—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged by fluid current, e.g. air-lay
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/425—Cellulose series
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/54—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by welding together the fibres, e.g. by partially melting or dissolving
  • D04H1/559—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by welding together the fibres, e.g. by partially melting or dissolving the fibres being within layered webs
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/54—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by welding together the fibres, e.g. by partially melting or dissolving
  • D04H1/56—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by welding together the fibres, e.g. by partially melting or dissolving in association with fibre formation, e.g. immediately following extrusion of staple fibres
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/08—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating
  • D04H3/16—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating with bonds between thermoplastic filaments produced in association with filament formation, e.g. immediately following extrusion
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H5/00—Non woven fabrics formed of mixtures of relatively short fibres and yarns or like filamentary material of substantial length
  • D04H5/06—Non woven fabrics formed of mixtures of relatively short fibres and yarns or like filamentary material of substantial length strengthened or consolidated by welding-together thermoplastic fibres, filaments, or yarns

Definitions

• the co-forming process involves melt spinning continuous filaments from polymer resin, and simultaneously, directing an air stream with entrained distributed cellulose fibers together with the filaments, typically into a co-forming box or similar blending apparatus, blending the filaments and fibers, and directing the blend along to a collecting/forming structure such as a moving forming belt.
• the filaments may be spun and introduced into the airstream carrying the cellulose fibers, or an airstream carrying the cellulose fibers may be introduced into the pathway of the filaments following spinning, the effect being the deposit of an entangled blend of filaments and fibers onto the moving forming structure and accumulation and formation of a batt thereof.
• a cohesive fibrous web structure may be formed.
• the co-forming process is, advantageously, typically dry, in contrast to wet forming techniques often used to make products such as paper towels from cellulose pulp.
• the co-formed fibrous web structure may be used, for example, as a wet wipe substrate.
• the entangled polymer filaments in the co-formed structure provide a matrix that holds the relatively short fibers, entangled there within, in place within the structure, and thereby help maintain structural integrity of the structure when it is wetted with an aqueous lotion.
• the fibrous web structure from which wet wipes should be strong enough when moistened with a lotion to maintain structural integrity in use, but also soft enough to give a pleasing and comfortable tactile sensation to the user.
• the structure should have suitable absorbency, porosity and surface texture to be effective in absorbing, retaining and carrying an aqueous lotion, releasing the lotion under pressure during use, and in cleaning soiled skin, while at the same time providing a reliable barrier between the user' s hand and the soil (e.g. , fecal matter).
• meltblown polymer filaments alone can be formed on the outermost surfaces of the co-formed batt prior to bonding, to beneficial effect. It is surmised that the addition of the meltblown layer (called “scrim”) can help reduce release of lint (comprising fibers dislodged from the structure) during use by a consumer.
• Fig. 1 is a schematic perspective illustration of an example of a fibrous web structure.
• Fig. 2 is a schematic, cross-sectional representation of Fig. 1 taken along line 4-4;
• Fig. 3 is a scanning electron microscope image of a cross-section of an example of fibrous web structure.
• Fig. 4 is a schematic, perspective illustration of an example of a fibrous web structure.
• Fig. 5 is a schematic, cross-sectional representation of an example of a fibrous web structure.
• Fig. 6A is a schematic, cross-sectional illustration of an example of a fibrous web structure.
• Fig. 6B is a scanning electron microscope image of a plan view of an example of scrim formed of meltblown filaments (overlying an unrelated supporting surface).
• Fig. 6C is a scanning electron microscope image of cross-section of an example of a fibrous web structure depicting outer scrim layers formed of meltblown filaments sandwiching a core layer formed of a blend of pulp fibers and meltblown filaments.
• Fig. 6D is a scanning electron microscope image of cross-section of an example of a fibrous web structure depicting outer scrim layers formed of meltblown filaments sandwiching a core layer formed of a blend of pulp fibers and meltblown filaments, proximate a thermal bond.
• Fig. 7A is a schematic illustration of an example of a system and process for making a fibrous web structure.
• Fig. 7B is a schematic illustration of another example of a system and process for making a fibrous web structure.
• Fig. 8 is a schematic illustration of an example of a patterned belt for use in a process.
• Fig. 9A is a schematic perspective- view illustration of a portion of an example of a spinneret with a plurality of nozzles and attenuation fluid outlets.
• Fig. 9B is a schematic end-view illustration of an example of a nozzle in a spinneret with a melt exit hole and an attenuation fluid outlet useful in spinning filaments.
• Fig. 10 is an example of a thermal bond pattern that can be imparted to a fibrous web structure.
• Fig. 11 is a schematic illustration of an example of a stack of wet wipes in a tub.
• Fig. 12 is a ternary plot of the fraction of pulp, the fraction of meltblown polypropylene filaments present in two scrim layers, and the fraction of meltblown polypropylene filaments in the core layer, of the total weight, of each of seventeen samples of fibrous web structures comprising pulp fibers and meltblown polypropylene filaments.
• Fig. 13 is an enlarged view of the portion of the plot of Fig. 12 occupied by data points.
• Fig. 14A is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting wet cross direction peak tensile strength according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure.
• Fig. 14B is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting wet machine direction peak tensile strength according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure.
• Fig. 14C is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting wet opacity according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure with a basis weight of 55 gsm.
• Fig. 14D is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting wet opacity according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure with a basis weight of 60 gsm.
• Fig. 14E is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting perceived flexibility (wet) according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure having a basis weight of 55 gsm.
• Fig. 14F is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting perceived flexibility (wet) according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure having a basis weight of 60 gsm.
• Fig. 14G is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting perceived surface roughness (wet) according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure.
• Fig. 14H is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting Consumer Preference Indication (CPI) (wet) according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure having a basis weight of 55 gsm.
• CPI Consumer Preference Indication
• Fig. 141 is a view of the portion of the plot shown in Fig. 13, overlaid with shaded bands reflecting application of a predictive model developed from the data points, predicting Consumer Preference Indication (CPI) (wet) according to the fraction of pulp fibers, the fraction of meltblown polypropylene filaments in scrim layers, and the fraction of meltblown polypropylene filaments in a core layer, of a fibrous web structure having a basis weight of 60 gsm.
• CPI Consumer Preference Indication
• Basis Weight is the weight per unit surface area (in a machine-direction / cross- direction plane) of a sample of web material (on one side), expressed in grams/meter 2 (gsm). Basis weight may be specified in manufacturing specifications, and also may be measured, and reflects the weight of the material prior to addition of any liquid composition.
• Co-formed fibrous web structure as used herein means that the fibrous web structure comprises an intermixed and/or entangled blend of at least two different materials wherein at least one of the materials comprises filaments, such as spun polymer filament (e.g. , filaments spun from polypropylene resin), and at least one other material, different from the first material, comprises fibers.
• a co-formed fibrous web structure comprises fibers, such as cellulose or wood pulp fibers, and filaments, such as spun polypropylene filaments.
• a co-formed fibrous web structure may also comprise solid particulate additives such as but not limited to absorbent gel materials, filler particles, particulate spot bonding powders or clays.
• Cross Direction or "CD” with respect to a fibrous web structure means the direction perpendicular to the predominant direction of movement of the fibrous web structure through its manufacturing line.
• Fiber means an elongate particulate having a limited length exceeding its width or diameter, i.e. a length to width ratio of no more than 200.
• a “fiber” is an elongate particulate as described above that has a length of less than 3 cm. Fibers are typically considered discontinuous in nature.
• Non-limiting examples of fibers include hardwood and softwood pulp fibers; hemp bast; bagasse; bamboo; corn stalk; cotton; cotton stalk; cotton linters; esparto grass; flax tow; jute bast; kenaf bast; reed; rice straw, sisal; switch grass; wheat straw; and synthetic staple (i.e., cut or chopped) spun fibers made from polyester, nylons, rayon (including viscose and lyocell); polyolefins such as polypropylene and
• Synthetic fibers may be monocomponent or multicomponent, e.g. , bicomponent.
• long fibers have an average length exceeding 10 mm
• medium length fibers have an average length of from 2 mm and 10 mm
• short fibers have an average length less than 2 mm.
• Fibrous web structure as used herein means a web or sheet structure formed of one or more types of filaments and/or fibers.
• the term “fibrous web structure” encompasses nonwovens.
• a “filament” is an elongate particulate having a theoretically unlimited length, but at least a length-to-width and/or length-to-diameter ratio greater than 500 and a length greater than 5.08 cm. Filaments are typically spun in a continuous process, and are, therefore, considered substantially “continuous” in nature, having an indeterminate length. Non-limiting examples of filaments include meltspun/meltblown or spunbond filaments spun from polymer resin.
• Non- limiting examples of materials that can be spun into filaments include natural polymers, such as starch, starch derivatives, cellulose and cellulose derivatives, hemicellulose, hemicellulose derivatives, chitin, chitosan, polyisoprene (cis and trans), peptides, polyhydroxyalkanoates, and synthetic polymers including, but not limited to, thermoplastic polymers, such as polyesters, nylons, polyolefins such as polypropylene, polyethylene, polyvinyl alcohol and polyvinyl alcohol derivatives, sodium polyacrylate (absorbent gel material), and copolymers of polyolefins such as polyethylene-octene, and biodegradable or compostable thermoplastic fibers such as polylactic acid, polyvinyl alcohol, and polycaprolactone. Filaments may be monocomponent or multicomponent, e.g. , bicomponent.
• “Like chemistry” with respect to two polymers, two blends of polymers, or a polymer and a blend of polymers, means that the two polymers, two blends of polymers, or a polymer and a blend of polymers, are capable of mixing at a temperature of 250 °C or lower, to form a single thermodynamic phase.
• Liquid composition refers to any liquid, including, but not limited to a pure liquid such as water, an aqueous solution, a colloid, an emulsion (including oil-in-water and water-in-oil), a suspension, a solution and mixtures thereof.
• aqueous solution refers to a solution that is at least about 20%, at least about 40%, or even at least about 50% water by weight, and is no more than about 95%, or no more than about 90% water by weight.
• liquid composition encompasses a lotion or other cleaning or skin conditioning formulation that may be included with wet wipes.
• “Meltblown” and forms thereof refer to a process of making filaments and webs thereof, in which filaments are spun by extruding streams of molten polymer resin under pressure through one or more spinnerets, and then substantially attenuating (elongating and reducing diameter and/or width of) the polymer streams following their exit from the spinnerets, with one or more high- velocity streams of heated air proximate the exits of the spinnerets.
• the air handling equipment (such as a manifold) may be a separate or integral part of the spinneret and is configured to direct the air stream(s) along path(s) at least partially parallel to the direction of extrusion of the polymer streams.
• Meltblown filaments are distinguished from polymer filaments made by other spunbond or melt-spinning processes by their comparatively very small diameter and/or very small width, imparted by the attenuating air streams, and typically have an average diameter or width of from 0.1 ⁇ to 30 ⁇ , 15 ⁇ , 10 ⁇ or even 5 ⁇ .
• the filaments may be air quenched with cooling air, or mist quenched with a mixture of cooling air and water droplets.
• the spun, attenuated and quenched fibers are then typically directed toward and accumulated in somewhat random, varying and entangled orientation on, a moving belt or rotating drum, to form a web.
• Nonwoven for purposes herein means a consolidated web of fibers, continuous filaments, or chopped or staple fibers of any nature or origin, or any blend thereof, which have been formed into a web, and bonded together by any means, with the exception of weaving or knitting.
• a nonwoven is an example of a fibrous web structure.
• Nonwoven does not include nonfibrous skin-like or membrane-like materials with a continuous structure sometimes identified or described as “films”.
• Nonwoven does not include a product, such as paper, in which cellulose pulp fibers are distributed via a wetlaying process to form a sheet or web, without the need for any post-formation bonding processes to complete formation of the sheet or web.
• Porate as used herein means a granular substance or powder.
• Predominate or a form thereof, with respect to a proportion of a component of a structure or composition, means that the component constitutes the majority of the weight of the structure or composition.
• Pre-moistened and “wet” are used interchangeably herein and refer to fibrous web structures and/or wipes which are moistened with a liquid composition prior to packaging, and may be packaged in an effectively moisture impervious container or wrapper. Such pre- moistened wipes, which can also be referred to as “wet wipes,” may be suitable for use for cleaning a baby's skin (such, as, e.g. , during a diaper change), as well the skin of older children and adults.
• Stack refers to an orderly pile of individually cut portions of fibrous web structure, e.g. , wipes. Based upon the assumption that there are at least three wipes in a stack, each wipe, except for the topmost and bottommost wipes in the stack, will be in direct contact with the wipe directly above and below itself in the stack. Moreover, when viewed from above, the wipes will be layered on top of each other, or superimposed, such that only the topmost wipe of the stack will be visible. The height of the stack is measured from the bottom of the bottommost wipe in the stack to the top of the topmost wipe in the stack and is provided in units of millimeters (mm).
• Surfactant refers to materials which preferably orient toward an interface.
• Surfactants include the various surfactants known in the art, including: nonionic surfactants; anionic surfactants; cationic surfactants; amphoteric surfactants, zwitterionic surfactants; and mixtures thereof.
• the quantity of a component of a fibrous web structure is expressed in "X weight percent” or "X percent by weight,” or an abbreviated or shortened form thereof, the quantity means that the component' s weight constitutes X percent of the total weight of the fibrous web structure.
• z-direction with respect to a web or a fibrous web structure means the direction orthogonal to the plane defined by the machine direction and cross direction of the web or fibrous web structure.
• component or composition levels are in reference to the active level of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources.
• a fibrous web structure within the scope of the present invention may have a basis weight between about 10 gsm to about 120 gsm and/or from about 20 gsm to about 110 gsm and/or from about 30 gsm to about 100 gsm and/or from about 40 to 90 gsm.
• a fibrous web structure as disclosed herein having a basis weight from 40 gsm to 90 gsm and more preferably from 45 gsm to 85 gsm strikes the best balance between thickness/caliper, absorption capacity, opacity, drape and feel, and tensile strength, on one hand, and economy, on the other hand.
• the fibrous web structure may include additives such as softening agents, temporary wet strength agents, permanent wet strength agents, bulk softening agents, silicones, wetting agents, latexes, especially surface-pattern-applied latexes, dry strength agents such as
• carboxymethylcellulose and starch and other types of additives suitable for inclusion in and/or on fibrous web structures.
• Fibrous web structures with the scope of the present invention may be formed of a plurality of filaments, a plurality of fibers, and a mixture of filaments and fibers.
• Figs. 1 and 2 show schematic representations of an example of a fibrous web structure.
• Fibers useful as components of the fibrous web structure include cellulosic fibers commonly known as wood pulp fibers.
• Applicable wood pulps include chemical pulps, such as Kraft, sulfite, and sulfate pulps, as well as mechanical pulps including, for example,
• thermomechanical pulp groundwood, thermomechanical pulp and chemically modified thermomechanical pulp.
• Pulps derived from both angiosperm (flowering) trees may be preferred since they impart a superior tactile sense of softness to tissue sheets made therefrom. Pulps derived from both angiosperm (flowering) trees
• hardwood and gymnosperm (coniferous) trees
• softwood may be utilized.
• the hardwood and softwood fibers can be blended, or alternatively, can be deposited in layers to provide a stratified web.
• U.S. Pat. No. 4,300,981 and U.S. Pat. No. 3,994,771 are incorporated herein by reference for the purpose of disclosing layering of hardwood and softwood fibers.
• fibers derived from recycled paper which may contain any or all of the above categories as well as other non-fibrous materials such as fillers and adhesives used to facilitate the original papermaking.
• a blend of long, or medium-length, pulp fibers, and short pulp fibers may be suitable for purposes herein.
• long and medium-length fibers tend to be larger and more coarse, providing desirable texture and absorption characteristics, while short fibers tend to be finer and softer, enhancing opacity of the structure and adding tactile softness.
• Including short pulp fibers as a portion of the fiber blend may be beneficial for controllably including consolidated masses of fibers in the blend.
• a blend of softwood pulp fibers (medium- length) and hardwood pulp fibers (short) may be used.
• the softwood and hardwood pulp fibers, or medium- length and short fibers may be included in a weight ratio of 20:80 to 90: 10.
• the weight ratio of softwood fibers to hardwood fibers, or weight ratio of medium- length fibers to short fibers may be from 60:40 to 90:10, more preferably 65:35 to 85:15, and still more preferably 70:30 to 80:20 in the structure.
• the softwood pulp fibers may be SSK (southern softwood kraft) pulp fibers.
• the hardwood pulp fibers may be birch, aspen or eucalyptus pulp fibers.
• the softwood pulp fibers may be SSK pulp fibers and the hardwood pulp fibers may be birch, aspen or eucalyptus pulp fibers.
• Aspen, birch or eucalyptus pulp fibers may be desirable for their fineness, shortness, and softness, which contribute to enhancing opacity and softness of the fibrous web structure, and eucalyptus pulp may be particularly preferred for these characteristics.
• cellulosic fibers such as cotton linters, rayon, lyocell, viscose and bagasse may be used.
• Other sources of cellulose in the form of fibers or materials capable of being spun into fibers include grasses and grain sources.
• the fibrous web structure 10 may be a co-formed fibrous web structure.
• the fibrous web structure 10 comprises a plurality of filaments 12, such as polypropylene filaments, and a plurality of fibers, such as wood pulp fibers 14.
• the filaments 12 may be randomly arranged as a result of the process by which they are spun and/or formed into the fibrous web structure 10.
• the wood pulp fibers 14, may be randomly dispersed throughout the fibrous web structure 10 in the x-y (machine-direction/cross-direction) plane.
• the wood pulp fibers 14 may be non-randomly dispersed throughout the fibrous web structure in the z-direction. In one example (not shown), the wood pulp fibers 14 are present at a higher concentration on one or more of the exterior, x-y plane surfaces than within the fibrous web structure along the z- direction.
• Fig. 3 shows a cross-sectional, scanning electron microscope image of an example of a fibrous web structure 10a including a non-random, repeating pattern of microregions 15a and 15b.
• the microregion 15a (typically referred to as a "pillow") exhibits a different value of a localized property than microregion 15b (typically referred to as a "knuckle").
• the microregion 15b is a continuous or semi-continuous network and the microregion 15a are discrete regions within the continuous or semi-continuous network.
• the localized property may be caliper. In another example, the localized property may be density.
• a fibrous web structure is a layered fibrous web structure 10b.
• the layered fibrous web structure 10b includes a first layer 16 comprising a plurality of filaments 12, such as polypropylene filaments, and a plurality of fibers, in this example, wood pulp fibers 14.
• the layered fibrous web structure 10b further comprises a second layer 18 comprising a plurality of filaments 20, such as polypropylene filaments.
• the first and second layers 16, 18, respectively are sharply defined zones of concentration of the filaments and/or fibers.
• the plurality of filaments 20 may be deposited directly onto a surface of the first layer 16 to form a layered fibrous web structure that comprises the first and second layers 16, 18, respectively.
• the layered fibrous web structure 10b may comprise a third layer 22, as shown in Fig. 4.
• the third layer 22 may comprise a plurality of filaments 24, which may be the same or different from the filaments 20 and/or 16 in the second 18 and/or first 16 layers.
• the first layer 16 is positioned, for example sandwiched, between the second layer 18 and the third layer 22.
• the plurality of filaments 24 may be deposited directly onto a surface of the first layer 16, opposite from the second layer, to form the layered fibrous web structure 10b that comprises the first, second and third layers 16, 18, 22, respectively.
• Fig. 5 is a cross-sectional schematic illustration of another example of a fibrous web structure comprising a layered fibrous web structure 10c.
• the layered fibrous web structure 10c includes a first layer 26, a second layer 28 and optionally a third layer 30.
• the first layer 26 may comprise a plurality of filaments 12, such as polypropylene filaments, and a plurality of fibers, such as wood pulp fibers 14.
• the second layer 28 may comprise any suitable filaments, fibers and/or polymeric films.
• the second layer 28 comprises a plurality of filaments 34.
• the filaments 34 comprise a polymer selected from the group consisting of: polysaccharides, polysaccharide derivatives, polyvinylalcohol, polyvinylalcohol derivatives and mixtures thereof.
• a fibrous web structure may include two outer layers consisting of 100% by weight filaments and an inner layer consisting of 100% by weight fibers.
• the material forming layers 26, 28 and 30 may be in the form of layers wherein two or more of the layers may be combined to form a fibrous web structure.
• the layers may be bonded together, such as by thermal bonding and/or adhesive bonding, to form a multi-layer fibrous web structure.
• the fibrous web structure lOd may comprise two or more layers, wherein one layer 36 comprises any suitable fibrous web structure in accordance with the present disclosure, for example fibrous web structure 10 as shown in Figs. 1 and 2 and another layer 38 comprising any suitable fibrous web structure, for example a fibrous web structure comprising filaments 12, such as polypropylene filaments.
• the fibrous web structure of layer 38 may be in the form of a net, mesh, scrim or other structure that includes pores that expose one or more portions of the fibrous web structure lOd to an external environment and/or at least to liquids that may come into contact, at least initially, with the fibrous web structure of layer 38.
• layer 38 may be a layer of scrim formed of a deposit of somewhat, or substantially, randomly laid and/or accumulated meltblown polymer filaments.
• the fibrous web structure lOd may further comprise layer 40.
• Layer 40 may comprise a fibrous web structure comprising filaments 12, such as polypropylene filaments, and may be the same or different from the fibrous web structure of layer 38.
• Two or more of the layers 36, 38 and 40 may be bonded together, such as by thermal bonding and/or adhesive bonding, to form a multi-layer fibrous web structure.
• a bonding operation especially a thermal bonding operation, it may be difficult to distinguish the layers of the fibrous web structure lOd and the fibrous web structure lOd may visually and/or physically be similar to a layered fibrous web structure in that one would have difficulty separating the once individual layers from each other.
• layer 36 may comprise a fibrous web structure that exhibits a basis weight of at least about 15 gsm and/or at least about 20 gsm and/or at least about 25 gsm and/or at least about 30 gsm up to about 120 gsm and/or 100 gsm and/or 80 gsm and/or 60 gsm and the layers 38 and 42, when present, independently and individually, may comprise fibrous web structures that exhibit basis weights of less than about 10 gsm and/or less than about 7 gsm and/or less than about 5 gsm and/or less than about 3 gsm and/or less than about 2.5 gsm, or from greater than 0 gsm to less than about 2.5 gsm, or from 0.5 gsm to 2.5 gsm.
• Layers 38 and 40 when present, may help retain the fibers, in this case the wood pulp fibers 14, on and/or within the fibrous web structure of layer 36 thus reducing lint and/or dust (as compared to a single-layer fibrous web structure comprising the fibrous web structure of layer 36 without the layers 38 and 40) resulting from the wood pulp fibers 14 becoming free from the fibrous web structure of layer 36.
• Fig. 6B is a scanning electron microscope image of a plan view of an example of scrim layer (overlying an unrelated supporting surface) that may be formed in a meltblowing process, creating a network of substantially randomly-laid, continuous fine filaments.
• the thickness and basis weight of the layer may be controlled by controlling the rate of throughput of polymer resin through the meltblowing equipment, and the rate of speed of the collecting belt, drum or other surface upon which the filaments are collected after spinning.
• the filaments create a highly porous network of fine filaments.
• Figs. 6C and 6D are scanning electron microscope images of cross-sections of examples of a fibrous web structure depicting outer scrim layers 38, 40 formed of meltblown fibers, sandwiching a core layer 36 formed of a blend of pulp fibers and meltblown filaments.
• the continuous filaments of the scrim layers 38, 40 are substantially finer than the pulp fibers in the core layer 36.
• the scrim layers serve to help contain the relatively shorter and coarser pulp fibers within the structure.
• this desirably reduces release of pulp fibers into the plant environment in downstream processes involving the fibrous nonwoven structure, reducing contamination of equipment, among other benefits.
• this desirably increases abrasion resistance of the product and reduces shedding of pulp fibers ("linting") from rubbing friction of the product during its use.
• inclusion of scrim layers imparts added tensile strength to the fibrous web structure, even when it constitutes a mere reallocation of a portion of the meltblown filaments from the core layer. Added tensile strength reduces incidents of tearing and puncturing of the structure, benefitting both the manufacturer in downstream processing, and the consumer in use of a product made from the structure.
• the presence of polymer filaments in the core layer 36 together with the presence of polymer filaments of like chemistry in the two outer scrim layers facilitate formation of a thermal bond 70 at which the polymer material in the three layers can be brought together under heat and compression so that they at least partially fuse, as may be observed in Fig. 6D, thereby forming a robust bond through the web structure in the z-direction and holding the scrim layers to the structure. This helps maintain consolidation of the accumulated fibers and filaments, and enhances the structural integrity of the fibrous web structure. Further, it may be appreciated from Fig. 6D that the presence of scrim layers on a fibrous nonwoven web structure enables creation of a clearly, sharply defined thermal bond, which may enhance the visual appearance of thermal bond patterns that embody not only functional, but esthetic aspects.
• meltspun in one example meltspun and meltblown, polymer filaments in a co-formed fibrous web structure that is otherwise formed of cellulose or wood pulp fibers, as schematically illustrated in Figs. 1 and 2 serves to enhance the tensile strength and wet structural integrity of the structure, making it particularly suitable for making wet wipes.
• inclusion of outer scrim layers formed of meltspun, in one example meltspun and meltblown, polymer filaments as suggested and shown in Figs. 6A-6C serves to help contain the shorter and coarser pulp fibers within the structure.
• meltblown filaments to form outer scrim layers may be desirable because the relatively fine meltblown fibers form a scrim structure that is numerically dense (as compared to a structure of similar basis weight but formed of meltspun but not meltblown filaments), and therefore beneficial for containing fibers within the structure.
• the entire fibrous web structure be formed of at least 50 percent, more preferably at least 60 percent, and still more preferably at least 65 percent, by weight pulp fibers.
• the entire fibrous web structure include at least 10 percent, at least 20 percent, or at least 25 percent, by weight polymer filaments.
• the fibrous web structure be formed of 50 to 90 percent by weight pulp fibers, or 60 to 85 percent by weight pulp fibers, or even 65 to 85 percent by weight pulp fiber.
• the fibrous web structure may comprise 10 to 50 percent by weight polymer filaments, or 15 to 40 percent by weight polymer filaments, or even 15 to 35 percent by weight polymer filaments, respectively.
• Figs. 6A-6D what remains to be further decided is an appropriate allocation of polymer filaments between the inner or "core" layer(s) 36 and the outer scrim layers 38, 40 for purposes of best maximizing or appropriately balancing qualities such as drape or flexibility, surface roughness, tactile feel, opacity and tensile strength.
• any quantity ranging from a very small portion, to nearly all, of the polymer filaments in the structure may be allocated to the scrim layers.
• the seventeen variants were presented to the panel of human respondents, who were asked to evaluate the structure samples and rate them according to their perceptions of surface roughness. A subjective scoring system was used. Another regression analysis was applied to the data collected, and yielded a formula that is reflected in Fig. 14G. Generally, the formula predicts that relatively lower allocation of meltblown filaments to the scrim layers results in a relatively higher surface roughness rating, and vice versa, as reflected by shaded bands 161-164 in Fig. 14G.
• assessments described above do not appear to provide any certain guidance, prediction or expectation as to how to select a combination of weight percent pulp fiber content vs. meltblown filament content, and an allocation of meltblown filament content between the core layer and the scrim layers, that will be most pleasing to consumers of wet wipes such as baby wipes.
• Samples of the seventeen variants that had been converted to wet wipes were presented to another panel of consumer respondents, who were asked to evaluate the wipes samples and rate them according to the extent to which they would prefer to purchase them as consumers. A subjective scoring system was used.
• the Consumer Preference Indication formula suggests that the strongest consumer preference falls within a narrow band of allocation of meltblown polymer filaments to the outer scrim layers, from about 1.0 percent by weight of the total fibrous web structure allocated to the scrim layers, to about 13 percent by weight of the total fibrous web structure, of meltblown polymer filaments allocated to the scrim layers, for, e.g. , a 60 gsm fibrous web structure (Fig. 14F).
• Fig. 14F 60 gsm fibrous web structure
• a model derived from the regression analysis enables a prediction of consumer preference from the ranges of the basis weights and proportions of pulp fibers of the samples tested. From the analysis, it is preferred that the Consumer Preference Indication for a fibrous nonwoven structure be greater than 0.0, more preferably 1.0 or more, still more preferably 1.75 or more, and still more preferably 2.25 or more, where Consumer preference Indication is calculated according to the following equation:
• BW basis weight of the fibrous web structure in gsm.
• a fibrous web structure having a basis weight of 60 gsm and the following composition will be a within the range of consumer preference indicated by CPI as set forth above: 17.40 gsm meltblown polypropylene filaments in middle/core layer;
• the example structure will have 65.0 percent by weight pulp fibers, 6.00 percent by weight meltblown polymer filaments in the two scrim layers together, and 29.0 percent by weight meltbown polymer filaments in the middle/core layer, and will have a CPI of 2.4071 according to the above model, indicating a consumer-preferred structure.
• the structure would have 16.0 percent by weight meltblown polymer filaments in the two scrim layers, and 19.0 percent by weight meltbown polymer filaments in the middle/core layer, and will have a CPI of about -0.1108, indicating a structure that is outside the consumer-preferred range in which the CPI is greater than 0.
• meltblown polymer filaments to a basis weight of 4.8 gsm or less, by itself, is extremely thin and sheer, and barely tactilely perceptible when held in the hands. This illustrates the surprising sensitivity of consumer preference to allocation of meltblown filaments to the scrim layers, according to the model. It may be appreciated from the foregoing that consumer preferences are often elusive to prediction and that more than routine experimentation is necessary to discover them and then harmonize them with manufacturer preferences for features such as material strength, manufacturing cost and efficiency.
• examples of a fibrous nonwoven structure having a combination of the following features:
• Basis weight 40 gsm to 100 gsm, more preferably 50 gsm to 90 gsm, more preferably 55 to 85 gsm, and still more preferably 60 gsm to 80 gsm, or alternatively, any combination of the lower and upper values of the above ranges, e.g. , 40-85 gsm, 40-80 gsm, etc.;
• Composition 60 to 90 percent by weight cellulose fibers, preferably wood pulp fibers, and more preferably a blend of softwood and hardwood fibers, and still more preferably a blend of SSK fibers and hardwood fibers, for example, eucalyptus fibers; and 10 to 40 percent by weight meltblown polymer filaments, more preferably meltblown poly olefin filaments, and still more preferably meltblown filaments formed predominately of polypropylene; and
• meltblown filaments in scrim layers or more preferably, from about 3 weight percent to about 11 weight percent of the structure, of meltblown filaments in scrim layers, still more preferably, from about 5 weight percent to about 9 weight percent of the structure, of meltblown filaments in scrim layers, or alternatively,
• the basis weight of a single scrim layer is kept within a range of from 0.1 gsm to less than 3.0 gsm.
• the amount of meltblown polymer filaments allocated to the two scrim layers may be divided approximately equally, or may be divided unequally.
• the scrim layer on one side may be imparted with a lower basis weight of, for example, from 0.1 gsm to 1.4 gsm, or to 1.0 gsm, or even to 0.6 gsm.
• the scrim layer on the other side may be imparted with a higher basis weight of, for example, from 0.6 gsm to 3.0 gsm, or from 0.8 gsm to 2.8 gsm, or even from 1.0 gsm to 2.6 gsm.
• the basis weight of either scrim layer and preferably both scrim layers be at least 0.1 gsm, more preferably at least 0.2 gsm, or even more preferably at least 0.3 gsm.
• the weight percentage of either or preferably both scrim layers be at least 0.17%, or 0.34% combined.
• the basis weight of the fibrous web structure, the overall weight percent pulp content vs. meltblown filament content, and the allocation of meltblown filaments between core layer(s) and scrim layers may be adjusted and regulated by design, adjustment and regulation of the speeds and/or feed rates to components that introduce the materials in the manufacturing line, including the components that separate and feed the pulp fibers and entrain them in airstream(s), the banks of filament spinnerets, the forming belt, etc.
• the fibrous web structure and/or any product comprising such fibrous web structure may be subjected to any post-processing operations such as embossing operations, printing operations, tuft-generating operations, thermal bonding operations, ultrasonic bonding operations, perforating operations, surface treatment operations such as application of lotions, silicones and/or other materials, folding, and mixtures thereof.
• post-processing operations such as embossing operations, printing operations, tuft-generating operations, thermal bonding operations, ultrasonic bonding operations, perforating operations, surface treatment operations such as application of lotions, silicones and/or other materials, folding, and mixtures thereof.
• Non-limiting examples of suitable polypropylenes for making the filaments are commercially available from Lyondell-Basell and Exxon-Mobil. Any hydrophobic or non-hydrophilic materials within the fibrous web structure, such as polypropylene filaments, may be surface treated and/or melt treated with a hydrophilic modifier.
• Non-limiting examples of surface treating hydrophilic modifiers include surfactants, such as Triton X-100.
• Non-limiting examples of melt treating hydrophilic modifiers that are added to the melt, such as the polypropylene melt, prior to spinning filaments include hydrophilic modifying melt additives such as VW351 and/or S-1416 commercially available from Polyvel, Inc. and Irgasurf commercially available from Ciba.
• the hydrophilic modifier may be associated with the hydrophobic or non-hydrophilic material at any suitable level known in the art.
• the hydrophilic modifier is associated with the hydrophobic or non-hydrophilic material at a level of less than about 20% and/or less than about 15% and/or less than about 10% and/or less than about 5% and/or less than about 3% to about 0% by dry weight of the hydrophobic or non- hydrophilic material.
• the fibrous web structure may include optional additives, each, when present, at individual levels of from about 0% and/or from about 0.01% and/or from about 0.1% and/or from about 1% and/or from about 2% to about 95% and/or to about 80% and/or to about 50% and/or to about 30% and/or to about 20% by dry weight of the fibrous web structure.
• Non-limiting examples of optional additives include permanent wet strength agents, temporary wet strength agents, dry strength agents such as carboxymethylcellulose and/or starch, softening agents, lint reducing agents, opacity increasing agents, wetting agents, odor absorbing agents, perfumes, temperature indicating agents, color agents, dyes, osmotic materials, microbial growth detection agents, antibacterial agents and mixtures thereof.
• the fibrous web structure described herein may be converted to a sanitary tissue product or household cleaning product such as bath tissue or paper towels. It may be convolutedly wound about a core to form a roll. It may be combined with one or more other fibrous web structures as a layer to form a multi-layer product. In one example, a co-formed fibrous web structure may be convolutedly wound about a core to form a roll of co-formed product. A roll product may also be coreless.
• the fibrous web structure may be utilized to form a wipe.
• wipe is a general term to describe a sheet of material, typically cut from a non-woven web material, adapted for cleaning hard surfaces, food, inanimate objects, toys and body parts.
• many currently available wipes are adapted for use in cleaning of the perianal area of the body after defecation.
• Other wipes may be available for cleaning the face or other body parts.
• Multiple wipes may be attached together by any suitable method to form a mitt.
• the material from which a wipe is made should be strong enough to resist tearing during normal use, yet still provide softness to the user's skin, such as a child' s tender skin.
• the material should be at least capable of retaining its form for the duration of the user' s cleansing experience.
• Wipes may be generally of sufficient dimension to allow for convenient handling.
• the wipe may be cut and/or folded to such dimensions as part of the manufacturing process.
• the wipe may be cut into individual sheets so as to provide separate wipes which are often stacked, folded and interleaved in consumer packaging.
• the wipes may be in a web form where the web has been slit and folded to a predetermined width and provided with means (e.g. , perforations) to allow individual wipes to be separated from the web by a user. Wipes sheets divided by perforations may be gathered on a roll (in the manner of conventional dry bathroom tissue or paper towels).
• an individual wipe may have a length between about 100 mm and about 250 mm and a width between about 140 mm and about 250 mm.
• the wipe may be about 200 mm long and about 180 mm wide and/or about 180 mm long and about 180 mm wide and/or about 170 mm long and about 180 mm wide and/or about 160 mm long and about 175 mm wide.
• the material of the wipe may generally be soft and flexible, potentially having a structured surface to enhance its cleaning performance.
• the surface of the fibrous web structure may be substantially, macroscopically flat.
• the surface of the fibrous web structure may optionally contain raised and/or lowered portions. These can be in the form of logos, indicia, trademarks, geometric patterns, images of the surfaces that the substrate made from the structure is intended to clean (i.e. , infant's body, face, etc.). They may be randomly arranged on the surface of the fibrous web structure or be in a repetitive pattern of some form.
• the fibrous web structure may be biodegradable.
• the fibrous web structure may be made from a biodegradable material such as a polyesteramide, or high wet strength cellulose.
• the fibrous web structure is used to form a pre-moistened wipe, such as a baby wipe.
• a plurality of the pre-moistened wipes may be stacked one on top of the other and may be contained in a container, such as a plastic tub or a film wrapper.
• the stack of pre-moistened wipes (typically about 40 to 80 wipes/stack) may exhibit a height of from about 50 to about 300 mm and/or from about 75 to about 125 mm.
• the pre-moistened wipes may comprise a liquid composition, such as a lotion.
• the pre-moistened wipes may be stored long term in a stack in a liquid impervious container or film pouch without all of the lotion draining from the top of the stack to the bottom of the stack.
• the pre-moistened wipes are present in a stack of pre-moistened wipes that exhibits a height of from about 50 to about 300 mm and/or from about 75 to about 200 mm and/or from about 75 to about 125 mm.
• Wipes of the present invention may be saturation loaded with a liquid composition to form a pre-moistened wipe.
• the loading may occur individually, or after the fibrous web structures or wipes are place in a stack, such as within a liquid impervious container or packet.
• the pre-moistened wipes may be saturation loaded with from about 1.5 g to about 6.0 g and/or from about 2.5 g to about 4.0 g of liquid composition per gram of fibrous nonwoven structure.
• the liquid composition comprises water or another liquid solvent.
• the liquid composition is of sufficiently low viscosity to impregnate the entire structure of the fibrous web structure.
• the liquid composition may be primarily present at the fibrous web structure surface and to a lesser extent in the inner structure of the fibrous web structure.
• the liquid composition is releasably carried by the fibrous web structure, that is the liquid composition is carried on or in the fibrous web structure and is readily releasable from the fibrous web structure by applying some force to the fibrous web structure, for example by wiping a surface with the fibrous web structure.
• Liquid compositions useful in the present invention may be, but are not necessarily limited to, oil-in-water emulsions.
• the liquid composition may be at least 80% and/or at least 85% and/or at least 90% and/or at least 95% by weight water.
• the liquid composition When present on or in the fibrous web structure, the liquid composition may be present at a level of from about 10% to about 1000% of the basis weight of the fibrous web structure and/or from about 100% to about 700% of the basis weight of the fibrous web structure and/or from about 200% to about 500% and/or from about 200% to about 400% of the basis weight of the fibrous web structure.
• the liquid composition may comprise an acid.
• acids that may be included in the liquid composition are adipic acid, tartaric acid, citric acid, maleic acid, malic acid, succinic acid, glycolic acid, glutaric acid, malonic acid, salicylic acid, gluconic acid, polymeric acids, phosphoric acid, carbonic acid, fumaric acid and phthalic acid and mixtures thereof.
• Suitable polymeric acids can include homopolymers, copolymers and terpolymers, and may contain at least 30 mole % carboxylic acid groups.
• Specific examples of suitable polymeric acids useful herein include straight-chain poly(acrylic) acid and its copolymers, both ionic and nonionic, (e.g.
• the liquid composition comprises citric acid and/or citric acid derivatives.
• the liquid composition may also contain salts of the acid or acids used to lower the pH, or another weak base to impart buffering properties to the fibrous web structure.
• the buffering response is due to the equilibrium which is set up between the free acid and its salt. This allows the fibrous web structure to maintain its overall pH despite encountering a relatively high amount of bodily waste as would be found post urination or defecation in a baby or adult.
• the acid salt would be sodium citrate.
• the amount of sodium citrate present in the lotion would be between 0.01 and 2.0%, alternatively 0.1 and 1.25%, or alternatively 0.2 and 0.7% of the lotion.
• the liquid composition does not contain any preservative compounds.
• the liquid composition may comprise additional ingredients.
• additional ingredients include: skin conditioning agents (emollients, humectants) including waxes such as petrolatum, cholesterol and cholesterol derivatives; di- and tri-glycerides including sunflower oil and sesame oil; silicone oils such as dimethicone copolyol, caprylyl glycol; and acetoglycerides such as lanolin and its derivatives; emulsifiers; stabilizers; surfactants including anionic, amphoteric, cationic and nonionic surfactants; colorants; chelating agents including EDTA; sun screen agents; solubilizing agents; perfumes; opacifying agents; vitamins; viscosity modifiers such as xanthan gum; astringents; and external analgesics.
• skin conditioning agents emollients, humectants
• waxes such as petrolatum, cholesterol and cholesterol derivatives
• di- and tri-glycerides including sunflower oil and sesame oil
• liquid composition also may be formulated as described in any of, for example, U.S. patents nos. 8,221,774 and 8,899,003; and U.S. patent applications serial nos. 11/717,928;
• An opacifying lotion formulation such as described in, for example, U.S. patent application serial no. 13/220,982, may be particularly useful for imparting opacity to, or enhancing opacity of, a fibrous web structure, particularly one with a lower basis weight, e.g.
• Wipes of the present invention may be placed in the interior of a container, which may be liquid impervious, such as a plastic tub or a sealable packet, for storage and eventual sale to the consumer.
• the wipes may be folded and stacked.
• the wipes of the present invention may be folded in any of various known folding patterns, such as C-folding, Z-folding and quarter- folding. Use of a Z-fold pattern may enable a folded stack of wipes to be interleaved with overlapping portions.
• the wipes may include a continuous strip of material which has perforations between each wipe and which may be arranged in a stack or wound into a roll for dispensing, one after the other, from a container, which may be liquid impervious.
• the fibrous web structure or wipes of the present invention may further include prints, which may provide aesthetic appeal.
• prints include figures, patterns, letters, pictures and combinations thereof.
• FIG. 7A A non- limiting example of a method for making a co-formed fibrous web structure or a core layer thereof according to the present invention is schematically illustrated in Fig. 7A.
• the method illustrated in Fig. 7A comprises the step of mixing a plurality of fibers 14 with a plurality of filaments 12.
• the fibers 14 are wood pulp fibers, such as SSK fibers and/or eucalyptus fibers
• the filaments 12 are polypropylene filaments.
• the fibers 14 may be combined with the filaments 12, such as by being delivered to a stream of filaments 12 from a hammermill 42 via a fiber spreader 44 to form a mixture of filaments 12 and fibers 14.
• the filaments 12 may be created by meltblowing from a meltblowing spinneret 46.
• the mixture of fibers 14 and filaments 12 are collected on a collection device, such as a forming belt 48 to form a fibrous web structure 50.
• the collection device may be a patterned and/or molded belt that results in the fibrous web structure exhibiting a surface pattern, such as a non-random, repeating pattern of microregions.
• the patterned and/or molded belt may have a three-dimensional pattern on it that is imparted to the fibrous web structure 50 during the process.
• a patterned belt 48 as shown in Fig.
• the pattern may comprise a continuous or semi-continuous network 58 of the polymer resin 56 within which one or more discrete conduits 60 are arranged.
• a multilayer fibrous web structure 50 with outer scrim layers on both sides may be made in a single-pass, direct-forming process.
• Single pass means that the fibrous web structure is formed in a single continuous process, with no intervening gathering or storage of component layers, e.g. , on a roll.
• Direct forming means that each component layer of the structure following the first- formed layer is formed directly over the first layer or a later-formed layer, rather than being formed separately.
• a first meltblowing spinneret 46a may be used to spin a plurality of first meltblown filaments 12a that may be accumulated on a moving forming surface, such as the surface of a moving forming belt 48, to form a first scrim layer.
• a configuration of co-forming equipment that may include co-form meltblowing spinneret 46b, a fiber spreader 44, and a mixing box such as co-form box 74, may be arranged and configured to deliver meltblown filaments and air-entrained pulp fibers, respectively to the mixing box such as co-form box 74.
• the filaments and fibers may be blended, entangled and entrained in an air stream to form a co-form stream 14a, which may then be directed to a moving forming surface (such as belt 48) to accumulate and form a co-form layer.
• the co-form layer may be accumulated and formed directly over and overlying the first scrim layer.
• a plurality of configurations of co-forming equipment may be arranged in succession to deliver a plurality of co-form streams 14a in succession to build up the thickness and basis weight of the co-form layer accumulation. This may enable greater manufacturing line speed than use of only a single configuration of co-forming equipment, and may also provide a mechanism for increasing or regulating basis weight of the co-form layer when the operating speed of belt 48 is governed by other concerns, e.g. , the desired basis weight of the scrim layer(s).
• a second meltblowing spinneret 46b may be used to spin a plurality of second meltblown filaments 12b that may be accumulated on a moving forming surface, such as the surface of moving forming belt 48, to form a second scrim layer.
• the second scrim layer may be accumulated and formed directly over and overlying the previously-formed co-form layer.
• the fiber spreader(s) 44 may be configured, and may comprise equipment including an educator, as described in, for example, U.S. Patent App. Ser. No. 62/094,087.
• the co-form box may be configured as described in, for example, U.S. Patent App. Ser. No. 62/094,089.
• the process for forming the fibrous web structure may be a direct forming process in which the layers of the structure are formed sequentially by depositing components of overlying layers directly onto previously deposited components of underlying layers - as contrasted with a process in which one or more of the scrim and/or co- form layers are formed separately and, e.g. , conveyed as a fully-formed layer to the fibrous web structure forming process.
• a direct forming process may be preferred for purposes herein in which comparatively low basis weight scrim layers formed of meltblown filaments are contemplated, as such layers may in ordinary circumstances be too weak (i.e.
• a direct forming process provides another benefit. Without intending to be bound by theory, it is believed that formation of a layer by depositing fibers and/or filaments directly onto and over another previously-formed layer results in comparatively greater intermingling and/or entangling of fibers and/or filaments at the interface between the layers, providing a more unitized multilayer fibrous web structure in which the layers are less likely to separate, e.g. , in downstream processes or in consumer use of an end product made from the fibrous web structure.
• a single -pass, direct forming process may be more efficient by enabling greater manufacturing speeds, and less use of plant space and resources.
• the filament components of the fibrous web structure may be made using a meltblowing spinneret 46 comprising a plurality of filament nozzles 63 that may be arranged in rows, from which filaments are spun.
• Melted polymer may be extruded under pressure through the nozzles 63, whereby it is forced through the nozzles to exit as polymer streams from melt outlets 62.
• the spinneret may include annular attenuating fluid (e.g. , air) outlets 64 about the nozzles, from which heated, pressurized gaseous fluid (e.g.
• the nozzles or spinneret may include features to affect direction and/or features of the fluid streams (such as to induce or increase turbulence) about the exiting melted polymer streams, such as flutes 65.
• the hot gaseous fluid e.g. , air
• the melt outlet 62 may be concentrically or substantially concentrically positioned within the attenuating fluid outlet 64 such as is suggested in Figs. 9A and 9B.
• the filaments may be air quenched with cooling air.
• the filaments forming the scrim layers e.g. , those from spinnerets 46a and 46c, as shown in the example of Fig. 7B
• the filaments forming the scrim layers may be air-quenched, or mist quenched with a mixture of cooling air and water droplets. Mist-quenching is an efficient way to increase the rate of cooling of the scrim filaments and impart comparatively greater tensile strength and elongation capability to them.
• the water droplets evaporate quickly, removing heat, when they contact the combination of hot air and hot polymer streams, such that a subsequent drying step is not necessary. Chilling the cooling air (e.g.
• mist-quenching may in some circumstances not be deemed suitable for the filaments from the co-form meltblowing spinneret, as this may cause water to be introduced into the co-forming process, causing complications that may include clumping of pulp fibers, or the necessity, complication and expense of an additional drying step.
• the filaments may be directed directly at a moving collecting and/or forming surface such as a forming belt 48 (e.g. , as shown in Figs. 7A, 7B) to form scrim layer(s), or alternatively, may be directed into a co-form box 47 (e.g. , as shown in Fig. 7B) to form a co- form layer.
• a moving collecting and/or forming surface such as a forming belt 48 (e.g. , as shown in Figs. 7A, 7B) to form scrim layer(s), or alternatively, may be directed into a co-form box 47 (e.g. , as shown in Fig. 7B) to form a co- form layer.
• the layers may be calendered, for example, while the deposited layers of filaments and fibers are still on the collection device, or downstream thereof.
• the accumulated first scrim layer, co-form layer, and second scrim layer may be passed together into the nip 49c between a pair of calender rollers 49a, 49b.
• One or both of the calender rollers may have etched, machined or otherwise formed on its cylindrical surface a pattern of bonding protrusions having functional and/or decorative features and appearance; one possible example (among a practically unlimited number of variants) is shown in Fig. 10.
• One or both calender rollers 49a, 49b may be heated, or a source of heat energy (such as, for example, ultrasound energy) may be supplied at the nip, and the rollers may be configured to exert a controlled amount of pressure on the layers in the nip.
• a source of heat energy such as, for example, ultrasound energy
• the rollers may be configured to exert a controlled amount of pressure on the layers in the nip.
• the polymer(s) or blend(s) thereof forming the filaments of the respective scrim layers 38, 40 and the filaments in the co-form layer(s) 36 be of like chemistry.
• formation of the first scrim layer, core layer(s) and second scrim layer, and consolidation and thermal bonding of the layers to form a bonded fibrous web structure may be performed in a single pass, direct forming process, i.e. , with no intervening conveying, gathering or storing of layers occurring between the formation thereof, and formation of the completed fibrous web structure.
• This may be process- and cost-efficient, and also removes the need for a minimum basis weight for scrim layers sufficient to make them self-supporting for purposes of conveying separately and/or gathering on a roll. In turn, this enables inclusion of relatively low basis weight scrim layers as contemplated herein, in the fibrous web structure.
• the surface area occupied by the bonds 70 relative to the total surface area of the fibrous web structure may be expressed as bond area percentage, and is calculated as the total surface area occupied by the bonds 70, divided by the overall surface area of a side of the fibrous web structure 50 on which the bonds appear, x 100%.
• Bond area percentage on a fibrous web structure approximately reflects bonding area percentage of the raised (bonding) surfaces of the bonding protrusions on a calender bonding roller, divided by the total surface area of the circumscribing cylindrical shape of the portion of the calender bonding roller that contacts the web structure in the nip. Bond area percentage may be increased or decreased by altering the design of the pattern of bonding protrusions on the calendar bonding roller.
• Bonding protrusions having larger bonding surface area and/or more dense spacing impart comparatively greater bond area percentage to the web structure, while bonding protrusions having smaller bonding surface area and/or less dense spacing impart comparatively lesser bond area percentage to the web structure.
• greater bond area percentage may impart comparatively greater machine and cross direction tensile strength, but also comparatively greater stiffness, in the web structure.
• thermal bond area percentage may be in a range of from 2% to 12%, more preferably from 3% to 10%, even more preferably from 4% to 8%, and still more preferably from 5% to 7%.
• the fibrous web structure 50 may be subjected to other post-processing operations such as embossing, tuft-generating operations, moisture-imparting operations, and surface treating operations to form the finished fibrous web structure.
• post-processing operations such as embossing, tuft-generating operations, moisture-imparting operations, and surface treating operations to form the finished fibrous web structure.
• a surface treating operation that the fibrous web structure may be subjected to is the surface application of an elastomeric binder, such as ethylene vinyl acetate (EVA), latexes, and other elastomeric binders.
• EVA ethylene vinyl acetate
• latexes latexes
• other elastomeric binders such as ethylene vinyl acetate (EVA), latexes, and other elastomeric binders.
• EVA ethylene vinyl acetate
• Such an elastomeric binder may aid in reducing the lint created from the fibrous web structure during use by
• the elastomeric binder may be applied to one or more surfaces of the fibrous web structure in a pattern, especially a non-random, repeating pattern of microregions, or in a manner that covers or substantially covers the entire surface(s) of the fibrous web structure.
• the fibrous web structure 50 and/or the finished fibrous web structure may be combined with one or more other fibrous web structures.
• another fibrous web structure such as a filament-containing fibrous web structure, such as a polypropylene filament fibrous web structure may be associated with a surface of the fibrous web structure 50 and/or the finished fibrous web structure.
• the polypropylene filament fibrous web structure may be formed by meltblowing polypropylene filaments (filaments that comprise a second polymer that may be the same or different from the polymer of the filaments in the fibrous web structure 50) onto a surface of the fibrous web structure 50 and/or finished fibrous web structure.
• the polypropylene filament fibrous web structure may be formed by meltblowing filaments comprising a second polymer that may be the same or different from the polymer of the filaments in the fibrous web structure 50 onto a collection device to form the polypropylene filament fibrous web structure.
• the polypropylene filament fibrous web structure may then be combined with the fibrous web structure 50 or the finished fibrous web structure to make a two-layer fibrous web structure - three-layer if the fibrous web structure 50 or the finished fibrous web structure is positioned between two layers of the polypropylene filament fibrous web structure like that shown in Fig. 4 for example.
• the polypropylene filament fibrous web structure may be thermally bonded to the fibrous web structure 50 or the finished fibrous web structure via a thermal bonding operation.
• the fibrous web structure 50 and/or finished fibrous web structure may be combined with a filament-containing fibrous web structure such that the filament- containing fibrous web structure, such as a polysaccharide filament fibrous web structure, such as a starch filament fibrous web structure, is positioned between two fibrous web structures 50 or two finished fibrous web structures like that shown in Fig. 6A for example.
• a filament-containing fibrous web structure such as a polysaccharide filament fibrous web structure, such as a starch filament fibrous web structure
• the method for making a fibrous web structure comprises the step of combining a plurality of filaments and optionally, a plurality of fibers to form a fibrous web structure that exhibits the properties of the fibrous web structures described herein.
• the filaments comprise thermoplastic filaments.
• the filaments comprise polypropylene filaments.
• the filaments comprise natural polymer filaments.
• the method may further comprise subjecting the fibrous web structure to one or more processing operations, such as calendaring the fibrous web structure.
• the method further comprises the step of depositing the filaments onto a patterned belt that creates a non-random, repeating pattern of micro regions.
• two layers of fibrous web structure 50 comprising a non-random, repeating pattern of microregions may be associated with one another such that protruding microregions, such as pillows, face inward into the two-layer fibrous web structure formed.
• the process for making a fibrous web structure 50 may be close coupled (where the fibrous web structure is convolutedly wound into a roll prior to proceeding to a converting operation) or directly coupled (where the fibrous web structure is not convolutedly wound into a roll prior to proceeding to a converting operation) with a converting operation to emboss, print, deform, surface treat, thermal bond, cut, stack or other post- forming operation known to those in the art.
• direct coupling means that the fibrous web structure 50 can proceed directly into a converting operation rather than, for example, being convolutedly wound into a roll and then unwound to proceed through a converting operation.
• the fibrous web structure is embossed, cut into sheets, and collected in stacks of fibrous web structures.
• a process according the present disclosure may include preparing individual rolls and/or sheets and/or stacks of sheets of fibrous web structure and/or sanitary tissue product comprising such fibrous web structure(s) that are suitable for consumer use.
• a fibrous web structure comprising: from 10 percent by weight to 40 percent by weight, more preferably from 15 percent by weight to 35 percent by weight, and even more preferably from 20 percent by weight to 30 percent by weight meltspun polymer filaments; and from 60 percent by weight to 90 percent by weight cellulose pulp fibers, more preferably from 65 percent by weight to 85 percent by weight cellulose pulp fibers, and still more preferably from 70 percent by weight to 80 percent by weight cellulose pulp fibers, wherein the fibrous web structure has first and second outer scrim layers formed of a first portion of said meltspun polymer filaments, and an inner core layer formed of said pulp fibers intermixed with a second portion of said meltspun polymer filaments, the fibrous web structure having a Consumer Preference Indication greater than 0, more preferably equal to or greater than 1.0, more preferably equal to or greater than 1.75, and still more preferably equal to or greater than 2.25, said first portion forming from 1 percent to 13 percent of the
• a fibrous web structure comprising: from 10 percent by weight to 40 percent by weight, more preferably from 15 percent by weight to 35 percent by weight, and even more preferably from 20 percent by weight to 30 percent by weight meltspun polymer filaments; and from 60 percent by weight to 90 percent by weight cellulose pulp fibers, more preferably from 65 percent by weight to 85 percent by weight cellulose pulp fibers, and still more preferably from 70 percent by weight to 80 percent by weight cellulose pulp fibers, wherein the fibrous web structure has first and second outer scrim layers formed of a first portion of said meltspun polymer filaments, and an inner core layer formed of said pulp fibers intermixed with a second portion of said meltspun polymer filaments, the first and second portions of said meltspun polymer filaments together comprising all of said meltspun polymer filaments, said first portion constituting from 1 percent to 13 percent of the weight of the fibrous web structure, more preferably from 3 percent to 11 percent of the weight of the fibrous web structure, and even more preferably from 5 percent to 9 percent of
• a fibrous web structure comprising: from 10 percent by weight to 40 percent by weight, more preferably from 15 percent by weight to 35 percent by weight, and even more preferably from 20 percent by weight to 30 percent by weight meltspun polymer filaments; and from 60 percent by weight to 90 percent by weight cellulose pulp fibers, more preferably from 65 percent by weight to 85 percent by weight cellulose pulp fibers, and still more preferably from 70 percent by weight to 80 percent by weight cellulose pulp fibers, wherein the fibrous web structure has first and second outer scrim layers formed of a first portion of said meltspun polymer filaments, and an inner core layer formed of said pulp fibers intermixed with a second portion of said meltspun polymer filaments, the first and second portions of said meltspun polymer filaments together comprising all of said meltspun polymer filaments, at least one of the scrim layers having a basis weight of from 0.1 gsm to less than 3.0 gsm, more preferably from 0.3 gsm to 2.8 gsm, and still more
• cellulose pulp fibers comprise softwood pulp fibers, preferably SSK fibers.
• cellulose pulp fibers comprise hardwood pulp fibers, preferably aspen, birch or eucalyptus fibers.
• first and second outer scrim layers each has a basis weight equal to or greater than 0.1 gsm.
• first and second outer scrim layers each has a basis weight less than 3.0 gsm, more preferably 2.8 gsm, and still more preferably 2.6 gsm.
• a wet wipe comprising the fibrous web structure of any of the preceding examples wetted with a liquid composition.
• nozzles per cross-direction inch of the 192 nozzles have a 0.018 inch inside diameter melt outlet hole while the remaining nozzles are plugged, i.e. , there is no opening in the nozzle.
• Approximately 0.18 grams per (open) hole per minute (ghm) of the melt blend is extruded from the open nozzles to form meltblown filaments from the melt blend.
• the solid additive spreaders turns the pulp fibers and distributes the pulp fibers in the cross -direction such that the pulp fibers are injected into the stream of meltblown filaments at a 45° angle through two 4 inch x 15 inch cross- direction (CD) slots.
• the pulp conveying ductwork and geometry are as described in U.S. Pat. App. Ser. Nos. 62/170,169 and 62/170,172.
• a forming box surrounds the area where the meltblown filaments and pulp fibers are commingled. This forming box is designed to reduce the amount of air allowed to enter or escape from this commingling area. The forming box is as described in U.S. Pat. App. Ser. No. 62/170,179.
• a forming vacuum pulls air through a moving collection surface, such as a non-patterned forming belt or through-air-drying fabric, thus collecting and accumulating the commingled meltblown filaments and pulp fibers to form a fibrous structure batt.
• a moving collection surface such as a non-patterned forming belt or through-air-drying fabric
• the forming vacuum level is adjusted to prevent excessive air from escaping from the forming box.
• the fibrous structure batt formed by this process comprises about 78% by dry fibrous structure weight of pulp and about 22% by dry fibrous structure weight of meltblown filaments.
• the line speed is adjusted (in the present example, to approximately 69 feet/min.) to accumulate the fiber/filament blend to reach the desired basis weight.
• the batt is then gathered on a storage roll.
• the resin blend is heated to approximately 400°F-405°F in a melt extruder.
• the melt extruder is used to feed the heated resin blend to a 15.5 inch wide Biax 12 row spinneret with 192 holes per cross-direction inch (Biax Fiberfilm Corporation, Greenville, WI) having 8 holes of the 192 holes per cross-direction inch with a 0.018 inch inside diameter melt outlet hole while the remaining nozzles are plugged.
• Biax 12 row spinneret with 192 holes per cross-direction inch (Biax Fiberfilm Corporation, Greenville, WI) having 8 holes of the 192 holes per cross-direction inch with a 0.018 inch inside diameter melt outlet hole while the remaining nozzles are plugged.
• the resin blend throughput in the spinneret is 0.18 grams per (open) hole per minute (ghm), i.e. , 22.32 grams resin minute through the spinneret.
• Compressed attenuating air is supplied to the spinneret at a rate of 426 SCFM, heated such that it is at a temperature of 395 °F at the spinneret.
• the attenuated filaments are water mist quenched using 2 misting nozzles, one on each broad side of the filament stream, each supplied with air at 35 psig and sufficient water supply for a flow rate of 2.5 gallons/hour.
• the filaments are directed to a first foraminous belt supplied with vacuum, operating horizontally and carrying the previously-formed coformed core layer (unwound from its storage roll) and controlled to move at a machine direction speed of approximately 86 feet/minute; the filaments are accumulated over the core layer on a first side thereof to a basis weight of approximately 2 gsm.
• a second scrim layer is formed by producing meltblown filaments in the same manner as for the first scrim layer as described above.
• the previously-made core layer and overlying first scrim layer are released from the first foraminous belt, turned 90 degrees on a roller, and passed to a second foraminous belt operating vertically (also supplied with vacuum and moving at 92 feet/minute), to carry the core layer and first scrim layer, with the first scrim layer in facing contact with the second foraminous belt.
• the filaments are directed toward the second foraminous belt and the core layer, to directly form a second scrim layer overlying the core layer, on a second side of the core layer.
• One bonding roller which is heated to 250 °F at its surface, has pattern of bonding protrusions machined thereon in the pattern reflected in Fig. 10, and having a bonding area of 6.2 percent.
• the layers are consolidated in the z-direction and thermally bonded in the pattern to form a thermally bonded fibrous web structure.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)
• Nonwoven Fabrics (AREA)
• Removal Of Specific Substances (AREA)
• Glanulating (AREA)
• Laminated Bodies (AREA)
• Paints Or Removers (AREA)

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• 2016
  • 2016-06-29 AR ARP160101967A patent/AR106076A1/es unknown
  • 2016-06-29 EP EP16738946.9A patent/EP3317369A1/en not_active Withdrawn
  • 2016-06-29 WO PCT/US2016/039949 patent/WO2017004116A1/en unknown
  • 2016-06-29 AR ARP160101966A patent/AR105189A1/es unknown
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