MXPA00012784A - Electro-spinning process to fabricate starch filaments for a flexible structure. - Google Patents

Abstract

The present disclosure provides a flexible structure comprising a plurality of starch filaments. The structure comprises at least a first region and a second region, each of these regions having at least an intrinsic common property selected from the group that consists of density, base weight, elevation, opacity, creping frequency and any combination of all of them. The intrinsic common property of the first region differs in value of the intrinsic common property of the second region.

Description

ELECTRO-YAR PROCESS FOR MANUFACTURING ALMONDON FILAMENTS FOR FLEXIBLE STRUCTURE FIELD OF THE INVENTION The present invention relates to flexible structures comprising starch filaments, and more specifically to flexible structures having differential regions. BACKGROUND OF THE INVENTION Cellulosic fibrous coils such as paper are known in the art. Low density fibrous coils are currently in common use for paper towels, tissue paper, facial tissue paper, sanitary napkins, diapers and the like. The high demand for such paper products has created a demand for improved versions of the products and methods of their manufacture. In order to meet such demands, paper manufacturers must balance the costs of machinery and resources with the total cost of supplying products to the consumer. For conventional papermaking operations, the cellulosic wood fibers are whipped again, whipped or refined to obtain a level of fiber hydration in order to produce a slurry of aqueous pulp. The Ref: 125834 process for the manufacture of paper products for use in tissue paper products, paper towels and napkins and sanitary products generally involves the preparation of an aqueous slurry and the subsequent removal of water from the slurry while rearranging the slurry. Contemporary way the fibers in it to form a continuous paper. Subsequent to dehydration, the coil is processed in the form of a dry roll or sheet and finally converted to a container for the consumer. Various types of machinery must be used to assist in the process of dehydration and transportation operations that require a significant investment in capital.

Other aspect in the conventional operation of papermaking involves the incorporation of additives into the pulp in order to obtain the specific final properties. For example, additives such as resins that improve strength, dissociation surfactants, softening agents, pigments, grids, synthetic microspheres, flame retardants, dyes, perfumes, etc., are often used in papermaking. The efficient retention of these additives in the wet end of the papermaking process presents difficulties to the manufacturer since this portion which is not retained creates not only an economic loss but also significant pollution problems if it becomes part of the effluent of a plant . The additives may also be added to the continuous paper subsequent to dehydration via coating or saturation processes commonly known in the art. These processes usually require that excess heating energy be consumed to re-dry the paper after coating. In addition, some systems require coating systems that are solvent-based, which increases capital costs and requires recovery of volatile materials to meet regulatory requirements. In the production of paper, various natural fibers other than cellulose have been used, as well as various synthetic fibers, however, all these substitutions have not provided a commercially acceptable substitute for cellulose due to its high cost, poor binding properties, incompatibility chemistry and handling difficulties in manufacturing systems. Starch filaments have been suggested as a substitute for cellulose in various aspects of papermaking processes, however, commercial attempts to use such starch filaments have not been successful. As a result, paper products still have to be processed almost exclusively from wood-based cellulosic ingredients. Accordingly, the present invention provides a flexible structure comprised of long starch filaments and a process for their manufacture. Particularly, the present invention provides a flexible structure comprising a plurality of starch filaments, wherein the structure comprises two or more regions having different intrinsic properties of improved strength, absorbency and smoothness. The present invention also provides methods for making starch filaments. Particularly, the present invention provides an electrospinning process for producing a plurality of starch filaments.

BRIEF DESCRIPTION OF THE INVENTION A flexible structure comprises a plurality of starch filaments. At least part of the plurality of starch filaments have a size from about 0.001 dtex to 135 dtex, and more specifically from 0.001 to 5 dtex. A dimensional proportion of a length of the major axis of at least some filaments of starch with respect to an equivalent diameter of a cross section perpendicular to the major axis of the starch filaments, is greater than 100/1, more specifically greater than 500. / 1, and even more specifically more than 1000/1, even more specifically more than 5000/1. The structure comprises at least a first region and a second region, each of the first and second regions having at least one common intrinsic property that is selected from the group consisting of density, weight, base, elevation, opacity, frequency of curly and any combination thereof. At least one common intrinsic property of the first region differs in value from at least one common intrinsic property of the second region. In one embodiment, one of the first and second regions comprises a substantially continuous rec., And the other of the first and second regions comprises a plurality of discrete areas dispersed through the substantially continuous network. In another embodiment, at least one of the first and second regions comprises a semi-continuous network. The flexible structure may further comprise at least a third region having at least one intrinsic property that is common and that differs in value from the intrinsic property of the prism region and the intrinsic property of the second region. In one embodiment, at least one of the first, second and third regions may comprise a substantially network. In another embodiment, at least one of the first, second and third regions may comprise separate areas. or discontinuous. In another additional embodiment, at least some of the first, second and third regions may comprise. as substantially semi-continuous. In another modality addition < ii, at least one of the first, second and third regions may comprise a plurality of separate areas dispersed through a substantially continuous network. In the embodiment wherein the flexible structure comprises a substantially continuous network region and a plurality of spaced apart areas dispersed through the substantially continuous network region, the substantially continuous network region may have a relatively high density relative to a relatively high density. low of the plurality of separate areas. When the structure is placed in a horizontal reference plane, the first region defines a first elevation, and the second region extends outwardly from the first region to define a second major elevation (relative to the horizontal reference plane) compared to the first elevation. In the embodiment comprising at least three regions, the first region can define a first elevation, the second region can define a second elevation, and the third region can define a third elevation when the structure is placed on a horizontal reference plane. At least one of the first, second and third elevations may be different from at least one of the elevations, for example, the second elevation may be intermediate at the first elevation and the third elevation. In one embodiment, the second region comprises a plurality of starch supports, wherein an individual support may comprise a dome portion extending from the first elevation to the second elevation, and a cantilevered portion extending laterally from the portion of dome in the second elevation. A density of the cantilever portion of starch may be equal to or different from at least one of the density of the first region and a density of the dome portion., or is intermediate to the density of the first region and the density of the dome portion. The cantilevered portions typically rise from the first plane to form substantially hollow spaces between the first region and the cantilevered portions. The flexible structure can be made by producing the plurality of starch filaments by melt spinning, dry spinning, wet spinning, electrospinning or by any combination thereof.; by providing a molding member having a three-dimensional filament receiving side structured to receive the plurality of starch filaments thereon, depositing the plurality of starch filaments to the filament receiving side of the molding member, wherein the plurality of filaments of starch is at least partially adapted to the pattern thereof, and to separate the plurality of starch filaments from the molding member. The step of depositing the plurality of starch filaments to the filament receiving side of the molding member may include causing the plurality of starch filaments to adapt at least partially to the three-dimensional pattern of the molding member. This can be carried out, for example, by applying a fluid pressure differential to the plurality of starch filaments. In one embodiment, the step of depositing the plurality of starch filaments to the molding members comprises depositing the starch filaments at an acute angle relative to the filament receiving side of the molding member, wherein the acute angle is approximately 5 mm. degrees to approximately 85 degrees. The molding member comprises, in one embodiment, a resinous infrastructure attached to a reinforcing element. The molding member may be fluid pervious, fluid impervious or partially fluid permeable. The reinforcement element can be placed between the filament receiving side and at least a portion of the supporting side of the infrastructure. The filament-receiving side may comprise a substantially continuous pattern, a substantially semi-continuous pattern, a discontinuous pattern or any combination thereof. The infrastructure may comprise a plurality of openings therethrough which may be continuous, separated or semi-continuous, in a manner analogous and inversely to the pattern of the infrastructure. In one embodiment, the molding member is formed by a reinforcement element placed at a first elevation, and a resinous infrastructure attached to the reinforcement element in a face-to-face relationship and extending outwardly from the reinforcement element to form a reinforcement element. second elevation. The molding member may comprise a plurality of interwoven strands, a felt or any combination thereof. When the plurality of starch filaments is deposited on the filament receiving side of the molding member, they tend, due to their flexibility or as a result of the application of a fluid pressure differential, or both, to adapt at least partially to the three-dimensional pattern of the molding member, whereby the first regions of the plurality of starch filaments supported by the drawn infrastructure are formed, and the second regions of the plurality of doubled filaments of starch within the opening or openings of the same and supported by the reinforcement element. In one embodiment, the molding member comprises suspended portions. The resinous infrastructure of such a molding member comprises a plurality of bases extending outward from the reinforcing member and a plurality of cantilevered portions extending laterally from the bases at the second elevation to form gaps between the cantilevered portions and the reinforcing element, wherein the plurality of bases and the plurality of cantilevered portions form, in combination, a three-dimensional filament receiving side of the molding member. Such a molding member can be formed by at least two layers that are joined in a face-to-face relationship such that these portions of the infrastructure of the layers correspond to the perforations in the other layer. The molding member comprising suspended portions may also be formed by differential curing of the photosensitive resin layer through a mask having a pattern comprising areas of differential opacity. The process for making the flexible structure of the present invention may further comprise a step of densifying selected portions of the plurality of starch filaments., for example, by applying mechanical pressure to the plurality of starch filaments. The process may further include a step of reducing the plurality of starch filaments. The reduction can be carried out by creasing, micro-shrinking or a combination thereof. An electrospinning process for making starch filaments comprises steps of providing a starch composition having an extension viscosity from about 50 pascal • seconds to about 20,000 pascal • seconds.; and the electrospinning of the starch composition therefore produces starch filaments having a size from about 0.001 dtex to about 135 dtex. The electrospinning step of the starch composition typically comprises electrospinning the starch composition through a die. The starch in the starch composition has an average molecular weight weight of from about 1000 to about 2,000,000, and the starch composition has a number of polarity of at least 0.05, and more specifically p at least 1.00. In one embodiment, the starch composition comprises from about 20% to about 99% by weight as amylopectin. The starch in the starch composition can have an average molecular weight weight of from about 1000 to about 2,000,000. The starch composition may comprise a high polymer having an average molecular weight weight of at least 500,000. The starch composition may comprise from about 10% to about 80% by weight of the starch and from a. { - Rely 20% to about 90% by weight of adit ^ v r. Such a starch composition can have an extc.isional viscosity from about 100 pascal • seconds ha < -at about 15,000 pascal • seconds at a temperature from about 20 ° C to about ltfO'C. The starch composition may comprise from about 20% to about 70% by weight of the starch and from about 30% to about 80% by weight of additives. Such a starch composition can have an extensional viscosity from about 200 pascal • seconds to about 10,000 pascal • seconds at a temperature of from about 20 ° C to about 100 ° C. The starch composition may have an extensional viscosity from about 200 pascal • seconds to about 1000 pascal • seconds and may have a capillarity number from about 3 to about 50. More specifically, the starch composition has an extension viscosity of about 300 pascal • seconds to about 5000 pascal • seconds and may have a capillarity number from about 5 to about 30. In one embodiment, the starch composition comprises from about 0.0005% to about 5% by weight of a high polymer substantially compatible with the starch and having an average molecular weight of at least 500,000.

The starch composition may comprise an additive which is selected from the group consisting of plasticizers and diluents. Such a starch composition may further comprise from about 5% to about 95% by weight of a protein, wherein the protein comprises a protein derived from corn, a protein derived from soybeans, a protein derived from wheat or any combination thereof. same. The process for making the starch filaments may further comprise a step of attenuating the starch filaments with air currents. In one embodiment, a process for making a flexible structure comprising starch filaments includes steps of providing a starch composition having an extension viscosity of from about 100 pascal • seconds to about 10,000 pascal • seconds; providing a molding member having a three-dimensional filament receiving side and a supporting side opposite thereto, the filament-receiving side comprises a substantially continuous pattern, a substantially semi-continuous pattern, a separate pattern or any combination thereof; electrospinning the starch composition, whereby a plurality of starch filaments are produced; and depositing the plurality of starch filaments on the filament receiving side of the molding member, whereby the starch filaments are adapted to the three-dimensional pattern of the filament receiving side. In an industrial process, the molding member is continuously moved in the machine direction.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic plan view of one embodiment of the flexible structure of the present invention. Figure IA is a schematic cross-sectional view taken along line 1A-1A of the figure 1. Figure 2 is a schematic plan view of another embodiment of the flexible structure of the present invention. Figure 3 is a schematic cross-sectional view of another embodiment of the flexible structure of the present invention. Figure 4 is a schematic plan view of an embodiment of a molding member that can be used to form the flexible structure of the present invention.

Figure 4A is a schematic cross-sectional view taken along line 4A-4A of the figure 4. Figure 5 is a schematic plan view of another embodiment of the molding member that can be used to form the flexible structure of the present invention. Figure 5A is a schematic cross-sectional view taken along line 5A-5A of Figure 5.

Figure 6 is a schematic cross-sectional view of another additional embodiment of the molding member that can be used to form the flexible structure of the present invention. Figure 7 is a side elevational and cross-sectional view, partially schematic, of an embodiment of an electrospinning process and an apparatus for making the flexible structure comprising starch filaments. Figure 7A is a schematic view taken along line 7A-7A of Figure 7. Figure 8 is a schematic side elevation view of one embodiment of a process of the present invention. Figure 9 is a schematic side elevational view of another embodiment of a process of the present invention. Figure 9A is a schematic side elevation view and a partial view of another embodiment of a process of the present invention. Fig. 10 is a schematic view of a fragment of an embodiment of a starch filament having differential cross-sectional areas perpendicular to the major (longitudinal) axis of the filament. Figure 10A is a schematic view of several exemplary, non-exclusive embodiments of a cross-sectional area of a starch filament. Figure 11 is a schematic view of a fragment of a starch filament having a plurality of notches along at least a portion of the length of the filament.

DETAILED DESCRIPTION OF THE INVENTION 'The following terms have the following meanings as used in this document. "Flexible structure comprising starch filaments" or simply "flexible structure" is an arrangement comprising a plurality of starch filaments that are entangled mechanically to form a sheet-like product having certain predetermined microscopic, physical and aesthetic geometrical properties. "Filaments of starch" is a thin, narrow and highly flexible object that comprises starch and has a major axis which is very long, in comparison with the two mutually orthogonal axes of the fiber that are perpendicular to the major axis. A dimensional proportion of the length of the major axis with respect to an equivalent diameter of the perpendicular cross section of the filaments with respect to the major axis is greater than 100/1, more specifically greater than 500/1, and in a more specific manner greater than 1000/1, and even more specifically more than 5000/1. The starch filaments may comprise other materials such as, for example, water, plasticizers and other optional additives.

The term "equivalent diameter" is used herein to define a cross-sectional area and u-n surface area of a single starch filament, regardless of the shape of the cross-sectional area. The equivalent diameter is a parameter that satisfies the equation S = 1/4 D2, where S is the cross-sectional area of the filament (regardless of its geometric shape), = 3.14159 and D is the equivalent diameter. For example, the cross section that has a rectangular shape formed by two mutually opposite sides "A" and two mutually opposite sides "B" can be expressed as: S = A x B. At the same time, this area in cross section can be expressed as a circular area having the equivalent diameter D. Thus, the equivalent diameter D can be calculated from the formula: S = 1/4 D2, where S is the known area of the rectangle (of course, the equivalent diameter of a circle is the actual diameter of the circle). An equivalent radius is 1/2 of the equivalent diameter. It is intended that the term "pseudothermoplastics" together with "materials". "compositions" indicate materials and compositions which, under the influence of elevated temperatures, dissolution in an appropriate solvent or in some other way, may be bent to a degree such that they may be in a flowable state, a condition in which they may be formed as desired, and more specifically, can be processed to form suitable starch filaments to form a flexible structure. The pseudo-thermoplastic materials can be shaped, for example, under the combined influence of heat and pressure. Pseudothermoplastic materials differ from thermoplastic materials in that softening or liquefying of pseudo-thermoplastics is caused by softeners or solvents present, without which it would be impossible to bring them under any temperature or pressure to a soft or flowable condition necessary for shaping, since pseudo-thermoplastics they do not "melt" as such. The influence of the water content on the vitreous transition temperature and the melting temperature of the starch can be measured by differential scanning calorimetry, as described by Zeleznak and Hoseny in "Cereal Chemistry", vol. 64, No. 2, p. 121-124, in 1987. Molten pseudo-thermoplastic is a pseudo-thermoplastic material in a flowable state. The term "microgeometry" and permutations thereof refer to relatively small (ie, "microscopic") details of the flexible structure, such as, for example, the texture of the surface, without considering the general configuration of the structure, in opposition with its general geometry (ie, "macroscopic"). The term "macroscopic" or "macroscopically" refers to the general geometry of a structure, or a portion thereof, under consideration when placed in a two-dimensional configuration, such as for example an X-Y plane. For example, at the macroscopic level, the flexible structure, when placed on a flat surface, comprises a relatively thin and flat sheet. At the microscopic level, however, the structure may be constituted of a plurality of regions forming a first plane having an elevation and a plurality of domes or "supports" dispersed through an extension outwardly from the region of the structure for form a second elevation. The "intrinsic properties" are properties which do not have a value that depends on an aggregation of values within the plane of the flexible structure. A common intrinsic property is an intrinsic property owned by more than one region. Such intrinsic properties of the flexible structure of the present invention include, without limitation, density, basis weight, elevation, opacity and frequency of creping (if the structure is to be reduced). For example, if a density is a common intrinsic property of two differential regions, a density value in one region may differ from a density value in the other region. Regions (such as, for example, a first region and a second region) are identifiable areas distinguishable from each other by different intrinsic properties. The "basis weight" is the weight (measured in grams of force) of a unitary area of the flexible structure of starch, a unit area which is taken in the plane of the structure of starch filaments. The size and shape of the unit area from which the basis weight is measured depends on the relative and absolute sizes and the shapes of the regions that have differential base weights. The term "density" is a ratio of basis weight to thickness (taken normal to the plane of the flexible structure) of a region. The bulk density is the base weight of the sample divided by the gauge with appropriate conversion units incorporated therein. The bulk density, as used in the present, has units of gram / cubic centimeters (g / cm3). "Caliber" is the macroscopic thickness of a sample measured as described in the following. The caliber must be distinguished from the elevation of the differential regions, which are microscopic characteristics of the regions. The "vitreous transition temperature", Tg, is the temperature at which the material changes from its viscous or rubber condition to a hard and relatively brittle condition. The "machine direction" (or MD) is the direction parallel to the flow of the flexible structure that is made, through the manufacturing team. The "cross machine direction" (or CD) is the direction perpendicular to the machine direction and parallel to the general plane of the flexible structure that is made.

"X", "Y" and "Z" indicate a conventional system of Cartesian coordinates, where the mutually perpendicular coordinates "X" and "Y" define a reference plane X-Y, and "Z" defines an orthogonal to the X-Y plane. The "Z direction" indicates any direction perpendicular to the X-Y plane. Analogously, the term "Z dimension" indicates a dimension, distance or parameter measured parallel to the Z direction. When an element, such as for example a molding member curves or changes plane in some other way, the XY plane follow the configuration of the element. A "substantially continuous" region (area / network / infrastructure) refers to an area within which one can connect any two points along an uninterrupted line that runs completely within the area across the length of the line. That is, the substantially continuous region has a substantial "continuity" in all directions parallel to the first plane and determined only at the edges of that region. The term "substantially", together with continuous, is intended to indicate that, although absolute continuity is preferred, minor deviations from absolute continuity are tolerable to the extent that these deviations do not appreciably affect the performance of the flexible structure (or a molding member) as it is designed and produced. The "substantially semicontinuous" region (area / network / infrastructure) refers to an area which has "continuity" in all directions, except one, parallel to the first plane, and area in which one can not connect any two points by one interrupted line that runs completely within that area through the length of the line. The semicontinuous infrastructure may have utility only in a direction parallel to the first plane. By analogy for the contiguous region, described above, although absolute continuity is preferred in all directions, except one, minor deviations from such continuity may be tolerated to the extent that these deviations do not appreciably affect the functioning of the structure (or member). of deflection). The "discontinuous" regions refer to discrete areas separated from each other, which are discontinuous in all directions parallel to the first plane. The term "absorbency" is the ability of a material to capture fluids by various means including capillarity, osmotic medium, solvents, or chemical action and to retain such fluids. The absorbency can be measured according to the test described here. The term "flexibility" is the ability of a material or structure to deform under a given load without breaking, regardless of the ability or inability of the material or structure to return to its pre-deformation form.

A "molded member" is a structure element that can be used as a support for the starch filaments that can be deposited thereon during a manufacturing process of the flexible structure of the present invention, and as a forming unit for forming the (or "molding") a desired microscopic geometry of the flexible structure of the present invention. The molding member may comprise any element that has the ability to impart a three-dimensional pattern to the structure that is produced thereon, and includes, without limitation, a stationary plate, a ribbon, a woven fabric and a band. The term "reinforcing element" is a desirable element, although not necessary, in some embodiments of the molding member, which mainly serves to provide or facilitate integrity, stability and durability of the molding member comprising, for example, a material resinous. The reinforcement element may be fluid pervious, fluid impervious or partially fluid permeable, and may comprise a plurality of interwoven yarns, a felt, a plastic or other suitable synthetic material, or any combination thereof. A "pressing surface" is a surface that can be pressed continuously. the side receiving filaments of the molding member having a plurality of starch filaments therein, to bend, at least partially, the starch filaments in the molding member having a three-dimensional pattern of depressions / protrusions therein. The terms "decitex" or "dtex" are units of measure for a filament of starch expressed in grams per 10,000 meters, grams. 10,000 meters The term "melt spinning" is a process by which a thermoplastic or pseudo-thermoplastic material is changed to a fibrous material by the use of an attenuation force. Melt spinning may include mechanical elongation, meltblowing, spinning and electrospinning. The term "mechanical elongation" is the process that induces a force in a strand of fiber that has to be brought into contact with a driven surface, for example a roller, to apply a force to the melt and thus form the fibers. The term "melt blown" is a process for producing fibrous coils or articles directly from polymers or resins using high velocity air or other appropriate force to attenuate the filaments. In a meltblowing process, the attenuation force is applied in the form of high velocity air as the material exits the die or the spinneret. The term "spunbonded" comprises the process of allowing the fiber to fall a predetermined distance under the forces of flow and gravity and then a force is applied by means of high velocity air or another suitable source. "Electrohilado" is a process that uses electrical potential as the force to attenuate the fibers. "Dry spinning", also commonly known as "spinning in solution" involves the use of solvent drying to stabilize fiber formation. A material is dissolved in an appropriate solvent and attenuated by mechanical elongation, meltblowing, spun bonding or electrospinning. The fiber becomes stable as the solvent evaporates. The term "wet spinning" comprises dissolving a material in a suitable solvent and forming small fibers via mechanical elongation, meltblowing, spinning or electrospinning. As the fiber is formed, it is directed to a coagulation system which normally comprises a bath filled with an appropriate solution that solidifies the desired material, whereby short fibers are produced. A high polymer "substantially compatible with starch" means that the high polymer is layers of forming a composition of a mixture substantially homogeneous with the starch (i.e., the composition that appears transparent or translucent to the naked eye) when the composition is heated to a temperature above the softening or melting temperature. The "melting temperature" means the temperature or the temperature range at or above which the composition of the starch melts or softens sufficiently to be capable of being processed into starch filaments, according to the present invention. It should be understood that some of the starch compositions are pseudo-thermoplastic compositions and as such may not exhibit a pure "melting" behavior. The "processing temperature" means the temperature of the starch composition, at which temperature the starch filaments of the present invention can be formed, for example, by attenuation.

Flexible structure With reference to Figures 1 to 3, the flexible structure comprises pseudo-thermoplastic starch filaments comprising at least a first region 110 and a second region 120. Each of the first and second regions have at least one common intrinsic property, such as, for example, a basis weight or density. The common intrinsic property of the first region 110 differs from the value of the common intrinsic property of the second region 120. For example, the density of the first region 110 may be greater than the density of the second region 120. The first and second regions 110 and 120 of the flexible structure 100 of the present invention can also be differentiated in their respective microgeometry. In Figure 1, for example, the first region 110 comprises a substantially continuous network that forms a first plane at a first elevation when the structure 100 is placed on a flat surface; and the second region 120 may comprise a plurality of separate areas dispersed through the substantially continuous network. These areas separated in some embodiments may comprise separate protuberances or "supports" that extend outwardly from the region of the network to form a second elevation greater than the first elevation, relative to the first plane. It should be understood that the supports may also comprise a substantially continuous pattern and a substantially semi-continuous pattern. In one embodiment, the substantially continuous network region may have a relatively high density, and the carriers have a relatively low density. In another embodiment, the substantially continuous network region may have a relatively low weight and the carriers may have a relatively high basis weight. In other additional embodiments, the substantially continuous network region may have a relatively low density, and the carriers may have a relatively high density. An embodiment is contemplated in which the substantially continuous network region may have a relatively high basis weight and the supports may have a relatively low basis weight. In other embodiments, the second region 120 may comprise a semi-continuous network. In Figure 2, the second region 120 comprises separate areas 122, similar to those shown in Figure 1; and semi-continuous areas 121, which extend in at least one direction, as seen in the X-Y plane (i.e., a plane formed by the first region 110 of the structure 100 placed on a flat surface). In the embodiment shown in Figure 2, the flexible structure 100 comprises a third region 130 having at least one intrinsic property that is common with, and that differs in value from, the intrinsic property of the first region 110 and the intrinsic property of the second region 120. For example, the first region 110 may have a common intrinsic property that has a first value, the second region 120 may have a common intrinsic property that has a second value, and the third region 130 may have a common intrinsic property having a third value, wherein the first value may be different from the second value, and the third value may be different from the second value and the first value .. When the structure 100 comprises at least three regions 110, 120 and 130 differentials, as described above, is placed on a horizontal reference plane (for example the XY plane), the first region 110 defines the plane that it has the first elevation and the second region 120 extends from it to define the second elevation. A modality is contemplated in which the third region 130 defines a third elevation, wherein at least one of the first, second, or third elevations is different from at least one of the "higher elevations." For example, the third elevation may be intermediate to the first and second elevations The following table shows, without limitation, some possible combinations of modalities of the structure 100 comprising at least three regions having differential intrinsic properties (ie, high, medium or low). All of these embodiments are included in the scope of the present invention.

Figure 3 shows another embodiment of the flexible structure 100 of the present invention, wherein the second region 120 comprises a plurality of starch supports, wherein at least part of the supports comprises a portion 128 of starch dome and a cantilever portion 129 of starch extending from the starch dome portion 128. The cantilever portion 129 of starch rises from the XY plane and extends, at an angle, from the dome portion 128 to form substantially hollow spaces or "cavities" 115 between the first region 110, the starch domes 128 extend from the same and portions 129 cantilevered starch. In large part due to the existence of these substantially hollow cavities 115 capable of receiving and retaining a significant amount of fluid, it is considered that the flexible structure 100 shown schematically in Figure 3 shows very high absorbency characteristics, for a basis weight dice. The cavities 115 are characterized in that they have a very small or nil amount of starch filaments therein. A person skilled in the art will appreciate that, due to a process of elaboration of the flexible structure 100 as discussed above, and due to the highly flexible nature of the starch filaments and the flexible structure as a whole, a certain amount of Individual starch filaments present in the cavities 115 may be tolerable to the extent that these starch filaments do not interfere with the designed pattern of the structure 100 and its proposed properties. In this context, the term "substantially" hollow cavities 115 is intended to recognize that, due to the highly flexible nature of the structure 100 and the individual starch filaments constituting the structure 100, a negligible amount can be found in the cavities 115. of filaments of starch or their portions. The density of the cavities 115 is not greater than 0.005 grams per cubic centimeter (g / cc), more specifically, not greater than 0.004 g / cc, and even more specifically not greater than 0.003 g / cc. In another aspect, the flexible structure 100 comprises cantilevered portions 129 which are characterized by an increased total surface area, relative to that of a comparable structure that does not have the cantilevered portions 129. A person skilled in the art will appreciate that the greater the number of individual cantilevered portions 129 as well as their respective microscopic surface areas, the greater the resulting microscopic surface area (ie, the resulting microscopic surface area per unit gross area). total of the structure placed on a flat surface). As will also be recognized by a person skilled in the art, the greater the surface area of absorption of a structure, the greater the absorption capacity thereof and all other parameters will be equal. In the embodiments of the structure 100 comprising cantilevered portions 129, the cantilevered portions 129 may be constituted by third regions of the structure 100. For example, a modality in which a density of the cantilevered portions 129 of starch is contemplated. is intermediate to a density of the first region 110 a density of the second region 120 comprising the dome portion (s). In another embodiment, the density of the dome portion 128 may be intermediate at a relatively high density of the first region 110 and a relatively low density of the cantilevered portion 129. By analogy, the base weight of the cantilever portion 129 may be equal to, or intermediate, or greater than one or both of the first region 110 and the dome portion 128.

Process for the development of the flexible structure Figures 8 and 9 schematically show two embodiments of a process for making a flexible structure 100, comprising starch filaments. First, a plurality of starch filaments are provided. The production of starch filaments for the flexible structure 100 according to the present invention can be made by various techniques known in the art. For example, starch filaments can be produced from thermoplastic molten starch compositions by various melt spinning processes. The sizes of the starch filaments may vary, from about 0.001 dtex to about 135 dtex, more specifically from 0.005 dtex to about 50 dtex, and even more specifically from about 0.01 dtex to about 5.0 dtex. Some references, including U.S. Patent No. 4,139,699 issued to Hernández et al., February 13, 1979; U.S. Patent No. 4,853,168 issued to Eden et al. , on August 1, 1989; and U.S. Patent No. 4,234,480 issued to Hernandez et al., on January 6, 1981, U.S. Patent Nos. 5,516,815 and 5,316,578 to Buehler et al., relate to starch compositions to make a starch filament using a melt spinning process. The molten starch composition can be extruded through a spinneret to produce filaments having slightly enlarged diameters relative to the diameter of the die holes of the spinel (e.g., due to a die expansion effect). Subsequently, the filaments are reduced by stretching, mechanically or thermomechanically by a stretching unit to reduce the fiber diameter. Various devices for producing non-woven thermoplastic fabric structures from extruded polymers are known in the art and may be suitable for making long flexible starch filaments. For example, an extruded starch composition can be driven through a spinneret (not shown) forming a vertically oriented curtain - of downwardly advancing starch filaments. The starch filaments can be cooled with air together with a suction-type air extraction or attenuation slot. U.S. Patent No. 5,292,239, issued to Zeldin et al., On March 8, 1994 describes a device that reduces significant turbulence in the air flow in order to uniformly and consistently apply a force of stretching to the filaments of starch. The description of this patent is incorporated herein by reference for limited purposes of teaching mode and equipment for reducing turbulence in the air flow when starch filaments are made. For the present invention, the starch filaments can be made from a mixture comprising starch, water, plasticizer- and other optional additives. For example, the suitable starch mixture can be converted to a pseudo-thermoplastic melt in an extruder and can be transported through a sputter to a drawing unit forming a vertically oriented curtain of downwardly advancing starch filaments. The spinneret may comprise a mount which. e known in the art. The spinneret may include a p1 uracity of nozzle perforations with holes that Je. in cross-sectional areas suitable for the production of starch filaments. The spinet can be adapted to the fluidity of the starch composition so that nozzle perforation has the same fiujc velocity, if desired. Alternatively, the flow velocities of the differential nozzles may vary. A drawing unit (not shown) may be located downstream of the extruder, and may comprise an open upper end, an open lower end opposite thereto, and an air supply manifold that provides compressed air to the internal nozzles oriented in an downward direction. As the compressed air flows through the internal nozzles, air is drawn into the open upper end of the extraction unit to form a rapidly moving stream of air flowing in the downward direction. The air stream produces a downward force on the starch filaments causing them to be attenuated or stretched before coming out at the open lower end of the stretching unit. It has now been found that the starch filaments suitable for the flexible structure 100 can be produced by an electrospinning process, wherein an electric field is applied to a starch solution to form a jet of charged starch. The electrospinning process is well known in the art. The dissertation entitled "The Electro-Spinning Process and Applications of Electro-Spun Fibers" by Doshi, Jayesh, Nat Arlal, Ph.D., 1994, describes an electrospinning process and conducts a study of the forces involved in the process. This dissertation also explores certain commercial applications of electrohilated filaments. This dissertation is incorporated herein by reference for purposes of describing the principles of the electrospinning process. U.S. Patent Nos. 1,975,504 (October 2, 1934); 2,123,992 (July 19, 1938); 2,116,942 (May 10, 1935); 2,109,333 (February 22, 1938); 2,160,962 (June 6, 1939); 2,187,306 (January 16, 1940); and 2,158,416 (May 16, 1939), all issued for Formhals, describe the electrospinning process and equipment for the same. Other references describing electrospinning processes include: U.S. Patent Nos. 3,280,229 (October 18, 1966) issued to Simons; 4,044,404 (August 30, 1977) issued to Martin et al .; 4,069,026 (January 17, 1978) issued to Simm et al; 4,143,196 (March 6, 1979) issued to Simm; 4,223,101 (September 16, 1980) issued to Fine et al .; 4,230,650 (October 28, 1980) issued for Guignard; 4,232,525 (November 11, 1980) issued to Enjo et al .; 4,287,139 (September 1, 1981) issued for Guignard; 4,323,525 (April 6, 1982) issued to Bornat; 4,552,707 (November 12, 1985) issued to How; 4,689,186 (August 25, 1987) issued to Bornat; 4,798,607 (January 17, 1989) issued to Middleton et al .; 4,904,272 (February 27, 1990) issued to Middleton et al .; 4,968,238 (November 6, 1990) issued to Satterfield et al .; 5,024,789 (January 18, 1991) issued to Barry; 6,106,913 (August 22, 2000) issued to Scardino et al .; and 6,110,590 (August 29, 2000) issued to Zarkoob et al. The descriptions of the patents mentioned above are incorporated herein by reference for the limited purpose of describing the general principles of the electrospinning process and the equipment therefor. Although the above references describe a variety of electrospinning processes and equipment therefor, they do not disclose the fact that a starch composition can be processed successfully and can be extruded into thin and substantially continuous starch filaments, suitable for making the structure 100 of the present invention. The starch that occurs naturally is not processable by an electrospinning process, because natural starch generally has a granular structure. It has now been discovered that a modified, "destructurized" starch composition can be processed successfully by using an electrospinning process. The commonly assigned patent application, entitled "Melt Processible Starch Composition" ((Larry Neil Mackey et al., Attorney's File # 7967R), filed on the filing date of the present application, describes a starch composition suitable for production. of the starch filaments used in the flexible structure 100 of the present invention The starch composition comprises starch having an average molecular weight ranging from about 1000 to about 2,000,000, and may contain a high polymer that is substantially compatible with starch and having an average molecular weight weight of at least 500,000 In one embodiment, the starch composition can have from about 20% to about 99% by weight amylopectin The description of this commonly assigned application is incorporated herein by reference In accordance with the present invention, it is possible to mix a p starch olimer with water, plasticizers and other additives, and the resulting melt can be processed (eg, extruded) and configured to produce suitable starch filaments for the flexible structure of the present invention. The starch filaments may have from a trace amount up to 100% starch, or may be a combination of starch and other suitable materials such as, for example, cellulose, synthetic materials, proteins and any combination thereof. The starch polymers can include any starch that occurs naturally, physically modified starch or chemically modified starch. Properly occurring starches may include, without limitation, corn starch, potato starch, beet starch, wheat starch, sago palm starch, tapioca starch, rice starch, soybean starch, and arrow root starch, fern starch, lotus starch, waxy corn starch, high amylose corn starch and commercial amylose powder. Starches that occur naturally, particularly corn starch, potato starch and wheat starch, are the starch polymers of choice because of their availability. Physically modified starch is formed by changing its dimensional structure. The physically modified starch may include alpha-starch, fractionated starch, heat and moisture treated starch, and mechanically treated starch. The chemically modified starch can be formed by reaction of its OH groups with alkylene oxide and other ether, ester, urethane, carbamate or isocyanate forming substances. Hydroxyalkyl, acetyl or carbamate starches, or mixtures thereof, are among the chemically modified starch forms. The degree of substitution of the chemically modified starch is from 0.05 to 3.0, and more especially from 0.05 to 0.2. A native water content can be from about 5% to about 16% by weight, and more specifically from about 8% to about 12%. The amylose content of the starch is from 0% to about 80%, and, more especially, from about 20% to about 30%. A plasticizer can be added to the cotton polymer to lower the vitreous transition temperature of the filaments being processed, thereby improving its flexibility. In addition, the presence of a plasticizer can lower the melt viscosity which in turn facilitates the melt extrusion process. The plasticizer is an organic compound having at least one hydroxyl group such as, for example, a polyol. Suitable sorbitol, mannitol, D-glucose, polyvinyl alcohol, ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, sucrose, fructose, glycerol and mixtures thereof have been found suitable. Examples of plasticizers include sorbitol, sucrose and fructose in amounts ranging from 0.1 wt.% To about 70 wt.%, More specifically from about 0.2 wt.% To about 301 wt., And even more specifically from approx. . 0.5% by weight to about 10% by weight. Typically: other additives may be included with the starch polymer as a processing aid and to modify the physical properties such as, for example, elasticity, dry strength and wet strength of the extruded starch filaments. The additives are typically present in amounts ranging from 0.1% to 70% by weight, in a non-volatile base (means that the amount is calculated by excluding volatiles such as water). Examples of additives include, without limitation, urea, urea derivatives, crosslinking agents, emulsifiers, surfactants, lubricants, proteins and their alkali salts, synthetic biodegradable polymers, waxes, synthetic thermoplastic polymers with low melting point, tackifying resins, diluents and mixtures thereof. Examples of biodegradable synthetic polymers include, without limitation, polylactone, polyhydroxybutyrates, polyhydroxyvalerate, polylactide and mixtures thereof. Other additives include optical brighteners, antioxidants, flame retardants, dyes, pigments and fillers. For the present invention, an additive comprises urea in amounts ranging from 0.5% to 60% by weight can be beneficially included in the starch composition. Suitable diluents for use herein include gelatin; vegetable proteins such as corn protein, sunflower protein, soybean proteins, cottonseed proteins; and water soluble polysaccharides such as alginates, carrageenans, guar gum, gum agar, gum arabic and related gums and pectins; and water soluble derivatives of cellulose such as alkylcelluloses, hydroxyalkylcelluloses, carboxymethylcellulose, etc. In addition, soluble synthetic polymers such as polyacrylic acids, polyacrylic acid esters, polyvinyl acetates, polyvinyl alcohols, polyvinylpyrrolidone, etc. can be used. Lubricating compounds can be added further to improve the flow of proteins of the starch material during the process of the present invention. Lubricating compounds may include animal or vegetable fats, preferably their hydrogenated form, especially those which are solid at room temperature. Additional lubricant materials include monoglycerides and diglycerides and phosphatides, especially lecithin. For the present invention, a lubricant compound including monoglyceride, glycerol monostearate, is considered beneficial. Additional additives include inorganic fillers such as magnesium, aluminum, silicon and titanium oxides, which can be added as cheap fillers or processing aids. Additionally, inorganic salts which include alkali metal salts, alkaline earth metal salts, phosphate salts, etc. can be used as processing aids. Other additives may be desirable, depending on the particular end use of the contemplated product. For example, in products such as tissue paper, disposable towels, tissue paper and other similar products, wet strength is a desirable attribute. Therefore, it is often desirable to add to the starch polymer crosslinking agents known in the art as "wet strength" resins. A general dissertation of the types of resistance resists in humero used in the paper technique can be found in the TAPPI series number 29, Wet Strength a Paper and Paperboard, Technical Association of the Pulp and Paper Industry (New York, 1965), which is incorporated herein by reference. The most useful resins with wet strength are generally cationic in nature. The polyamide-epichlorohydrin resins are wet-strength polyamide amine-epichlorohydrin cationic resins which have been found to be of particular utility. Suitable types of such resins are described in U.S. Patent 3,700,623, issued October 24, 1972, and 3,772,026, issued November 13, 1973, both issued to Keim, the disclosure of which is incorporated herein by reference . A commercial source of a useful polyamide-epichlorohydrin resin is Hercules, Inc. of Wilmington, Delaware, which sells such resins under the trademark Kymene ™.

It has also been found that glyoxylated polyacrylamide resins have utility as wet strength resins. These resins are described in U.S. Patent Nos. 3,556,932, issued January 9, 1971 to Coscua et al, and 3,556,933 issued January 19, 1971 to Williams et al., The disclosures of which are incorporated herein by reference . A commercial source of glyoxylated polyacrylamide resins is Cytec Co. of Stanford, Connecticut, which sells one such resin under the Parez ™ 631 NC brand. Other water-soluble cationic resins which can be used in this invention are urea formaldehyde and melamine formaldehyde resins. The most common functional groups of these polyfunctional resins are nitrogen containing groups such as amino groups and methylol groups attached to nitrogen. Polyetiienimine-type resins may also find utility in the present invention. In addition, temporary wet strength resins such as Caldas 10 (manufactured by Japan Carlit) and CoBond 1000 (manufactured by National Starch and Chemical Company) can be used in the present invention. For the present invention, a crosslinking agent is the Kymene ™ wet strength resin in amounts ranging from about 0.1 wt% to about 10 wt%, and more specifically from about 0.1 wt% to about 3 wt%. To produce starch filaments suitable for the flexible structure 100 of the present invention, the starch composition must show some rheological behavior during processing, such as a certain extensional viscosity and a certain number of capillarity. Of course, the type of processing (for example, meltblowing, electrospinning, etc.), can establish the required rheological qualities of the starch composition. The extensional or elongational viscosity (? E) is related to the molten extensibility of the starch composition and is particularly important for extensional processes such as starch filament processing. The extensional viscosity includes three types, depending on the type of deformation of the composition: simple uniaxial or extensional viscosity, biaxial extensional viscosity and pure cut extensional viscosity. Uniaxial extensional viscosity is especially important for uniaxial extensional processes such as mechanical elongation, meltblowing, bond spinning and electrospinning. The other two extensional viscosities are important for biaxial extension or processing processes to produce films, foams, sheets or parts. For conventional fiber spinning thermoplastics such as polyolefins, polyamides and polyesters, there is a strong correlation between the extensional viscosity and the cutting viscosity of these conventional thermoplastic materials and combinations thereof. That is, the spinnability of the material can be determined simply by the melt-cut viscosity, although the spinnability is a property controlled primarily by the melt extensional viscosity. The correlation is very strong so that the fiber industry has relied on the melt-cut viscosity to select and formulate melt-spinnable materials. Molten extensional viscosity has rarely been used as an industrifl analysis tool. Therefore, > , it is surprising to find that the starch compositions of the present invention do not necessarily show such a correlation between cut and extensional viscosities. The starch compositions herein show ur. Typical melt flow behavior of a non-Newtonian fluid and as such, may exhibit a stress hardening behavior, ie, the extensional viscosity. It increases as the tension or strain increases. For example, when a high polymer "affected in accordance with the present invention" is added to a starch composition., the cutting vjcosity of the composition remains relatively unchanged or even slightly decreases. Based on the conocii.i. In the conventional case, it would be expected that such a composition of ion will show a processing capacity in molten disinfection and would not be expected to be suitable for axtensional fusion processes. However, it has surprisingly been found that the starch composition in the present shows a significant increase in extensional viscosity when an even small amount of a high polymer is added. Accordingly, the starch composition herein is found to have increased melt extensibility and is suitable for cast extensional processes, especially those including meltblowing, spinning and electrospinning. A starch composition having a cutting viscosity, measured according to the test method described below, less than about 30 Pascal. second (Pa.s), more specifically from about 0.1 Pa.s to about 10 Pa.s, and even more specifically from about 1 to about 8 Pa.s is useful in the fusion attenuation processes herein. Some starch compositions herein may have a low melt viscosity so that they may be mixed, transported or otherwise processed in traditional polymer processing equipment typically used for viscous fluids, such as a stationary mixer equipped with a dosing pump and spine. The cutting viscosity of the starch composition can be effectively modified by the molecular weight and the molecular weight distribution of the starch, the molecular weight of the high polymer and the amount of plasticizers or solvents, or both, used.

It is considered that the reduction of the average molecular weight of the starch is an effective way to lower the cutting viscosity of the composition. In one embodiment of the present invention, the melt processable starch compositions have an extensional viscosity in the range of about 50 Pa. about 20,000 Pa.s, more specifically from about 100 Pa.s to about 15,000 Pa.s, more specifically from about 200 Pa.s to about 10,000 Pa.s, and even more specifically from about 300 Pa. .s up to about 5,000 Pa.s and even more specifically from about 500 Pa.s to about 3500 Pa.s at a certain temperature. The extensional viscosity is calculated according to the method established in the following in the section of Analytical Methods. Many factors can affect the rheological behavior (including the extensional viscosity) of the starch composition. Such factors include, without limitation: the amount and type of polymeric components used, the molecular weight and the molecular weight distribution of the components, which include starch and high polymers, the amylose content of the starch, the amount and type of additives (eg plasticizers, diluents, processing aids), the type of processing (eg meltblowing or electrospinning) and the processing conditions, such as temperature, pressure, deformation rate and relative humidity, and in the case of non-Newtonian materials, the antecedents of deformation (that is, dependence on time or stress history). Some materials can be hardened by tension, that is, their extensional viscosity increases as the tension increases. It is considered to be due to stretching of a tangled polymer network. Tension is removed from the material, the tensioned tangled polymer network relaxes at a lower voltage level, depending on the relaxation time constant, which is a function of the temperature, the molecular weight of the polymer, the concentration of solvent or plasticizer and other factors. The presence and properties of high polymers can have a significant effect on the extensional viscosity of the starch composition. The high polymers useful for improving the melt extensibility of the starch composition used in the present invention are typically substantially linear, high molecular weight polymers. In addition, high polymers that are substantially compatible with starch are most effective in improving the melt extensibility of the starch composition. It has been found that starch compositions useful for extensional melt processes typically have their extensional viscosity increased by a factor of at least 10 when a selected high polymer is added to the composition. Typically, the starch compositions of the present invention show an increase in extensional viscosity from a factor of from about 10 to about 500, more specifically from about 20 to about 300, even more specifically from about 30 to about 100, when add a selected high polymer. The higher the level of high polymer, the greater the increase in extensional viscosity. A high polymer can be added to adjust the extensional viscosity a. a value of 200 to 2000 Pa.sec at a Hencky tension of 6. For example, a polyacrylamide having a molecular weight (MW) of 1 million to 15 million at a level of 0.001% to 0.1% can be added to constitute the starch composition. The type and level of starch that is used can also have an impact on the extensional viscosity of the starch composition. In general, as the amylose content of the starch decreases, the extensional viscosity increases. As wellIn general, as the molecular weight of the starch increases within the prescribed range, the extensional viscosity increases. Finally, in general, as the level of starch in the compositions increases, the extensional viscosity increases (and inversely, in general, as the reactive level in the compositions increases, the extensional viscosity decreases). The temperature of the starch composition can significantly alter the extensional viscosity of the starch composition. For the purposes of the present invention, all conventional means can be used to control the temperature of the starch composition, if it is suitable for a particular process used. For example, in embodiments where the starch filaments are produced by extrusion through a die, the temperature of the die can have a significant impact on the extensional viscosity of the starch compositions that are extruded therethrough. In general, as the temperature of the starch composition increases, the extensional viscosity of the starch composition decreases. The temperature of the starch composition can vary from about 20 ° C to about 180 ° C, more specifically from about 20 ° C to about 90 ° C, and even more specifically from about 50 ° C to about 80 ° C. It should be understood that the presence or absence of solids in the starch composition can alter the temperature required for it. The Trouton relation (Tr) can be used to express the extensional flow behavior. The Trouton ratio is defined as the ratio between the extensional viscosity (e) and the shear viscosity (s), Tr = e (•, t) / s, where the extensional viscosity e depends on the deformation velocity (J and the time (t).) For a Newtonian fluid, the Trouton ratio of uniaxial extension has a constant value of 3. For a non-Newtonian fluid, such as the compositions of starch in the present, the extensional viscosity depends on the strain rate (J and time (t)) It has also been found that the melt processable compositions of the present invention typically have a trouton ratio of at least about 3. Typically, the Trouton ratio varies from about 10 to about 5,000, specifically from about 20 to about 1,000, and more specifically from about 30 to about 500, when measured at a processing temperature and an extension rate of 700 s "1 to a resistance Hencky oe 6. Requests., Have also found that in the modalities in which it occurs n starch filaments by extrusion, mme. or of capillarity (Ca) of the starch composition as it passes through the extrusion die, is important for 1 ,. processability. The capillary number is a number that represents the ratio of viscous fluid forces to surface tension forces. Near the outlet of the capillary die, if the viscous shells are not significantly larger than the surface tension forces, the fluid filament will break into droplets, which is commonly referred to as "atomization". The capillary number is calculated according to the following equation: Ca = Q) / ( where s is the cut viscosity in Pascal. seconds, measured at a cutting speed of 3,000 s "1; Q is the flow velocity of volumetric fluid through the capillary die, in m3 / s, r is the radius of the capillary die, in meters (for holes not circular, the equivalent diameter / radius can be used), and it is the surface tension of the fluid, in Newtons per meter, because the number of capillaries is related to the cutting viscosity as described above, it is affected by the same factors which affect the cutting viscosity in a similar manner As used herein, the term "inherent" together with the number of capillarity or surface tension indicates properties of a starch composition not altered by external factors, such as, for example , the presence of an electric field The term "effective" indicates the properties of the starch composition that has been altered by external factors, such as for example the presence of an electric field. embodiment of the present invention, the melt-processable starch compositions have an inherent capillarity number as they pass through the die of at least 0.01, and an effective capillarity number of at least 1.0. Without electrostatics, the capillary number needs to be greater than 1 for stability, and preferably greater than 5 for robust stability of the filament that is formed. With electrostatics, charge repulsion counteracts the effect of surface tension so that the number of inherent capillaries, measured without a present electric charge, can be less than 1. When an electric potential is applied to the filament that is formed, the Effective surface tension and the effective capillary number is increased based on the following equations: Although the number of capillarity can be expressed in variable forms, a representative equation, which can be used to determine the inherent capillarity number of a material is: ^ "intern - s' where : The coherent number is the inherent capillary number s is a viscosity of fluid cut is a linear velocity of the fluid is the surface tension of the fluid.

Insofar as it pertains to the present invention, a representative sample has the following composition and properties. Formula 59 purity rubber from National Starch Inc. 40.00% Deionized water 59.99% Superfloc N-300 LMW from Cytec (polyacrylamide 0.01% high molecular weight) Running temperature 49 ° C (120 ° F) Cutting viscosity at 300 s "1 0.1 Pa.s Nozzle diameter 0.0254 cm Line speed 0.236 m / sec Inherent surface tension 72 dynes / cm Experimentally, if an electrostatic charge in the fluid, this material will flow through the tip of the nozzle, forming small droplets and then falling under the force of gravity in separate drops. As the electrical potential increases in the system, the droplets become smaller in size and start accelerating towards the grounded mechanism. When the electric potential (25 Kilovolts for this example) reaches a critical value, no drops are formed at the tip of the nozzle and a small continuous fiber is ejected from the tip of the nozzle. Therefore, the applied electrical potential must now overcome the surface tension forces by eliminating the capillarity failure mode. The effective capillary number is now greater than 1. Laboratory experiments with the described solution and experimental settings produce essentially continuous fibers. The fibers are collected in a vacuum mesh in the form of a fiber mat. Analysis by optical microscopy shows that the resulting fibers are continuous and have diameters ranging from 3 to 5 micrometers. In some embodiments, the inherent capillarity number may be at least 1, more specifically from 1 to 100, still more specifically from about 3 to about 30, and even more specifically from about 5 to about 30. The starch composition herein is processed in a flowable state, which typically occurs at a temperature at least equal to or greater than the "melting temperature". Therefore, the processing temperature range is controlled by the "melting temperature" of the starch composition, which is measured according to the test method described in detail herein. The melting temperature of the starch composition herein varies from about 20 ° C to about 180 ° C, more specifically from about 30 ° C to about 130 ° C, and more specifically from about 50 ° C to approximately 90 ° C. The melting temperature of the starch composition is a function of the amylose content of the starch (a higher amylose content requires a higher melting temperature), the water content, the plasticizer content and the type of plasticizer. Exemplary uniaxial extensional processes suitable for starch compositions include meltblowing, meltblowing and spinning. These processes are described in detail in U.S. Patent Number 4,064,605, issued December 27, 1977 to Akiyama et al .; U.S. Patent Number 4,418,026, issued November 29, 1983 to Blackie et al .; U.S. Patent No. 4,855,179, issued August 8, 1989 to Bourland et al .; U.S. Patent No. 4,909,976, issued March 20, 1990 to Cuculo et al .; U.S. Patent Number 5,145,631, issued September 8, 1992 to Jezic; U.S. Patent Number 5,516,815, issued May 14, 1996 to Buehler et al .; and U.S. Patent No. 5,342,335, issued August 30, 1994 to Rhim et al .; whose descriptions in the foregoing are incorporated herein by reference. Figures 7, 8 and 9 schematically show an apparatus 10 for producing starch filaments suitable for the flexible structuring of the present invention. The apparatus 10 may comprise, for example, a single screw or double screw extruder, a positive displacement pump or a combination thereof., as is known in the art. The starch solution can have a total water content, ie, water of hydration plus water added, in the range of about 5% to about 80%, and more specifically in the range of about 10% to about 60% in relation to the total weight of the starch material. The starch material is heated at elevated temperatures sufficient to form a pseudo-thermoplastic fluid. Such a temperature is typically greater than the vitreous or melting transition temperature, or both, of the formed material. The polymeric melts of the invention are polymeric fluids having a cutting speed that depends on the viscosity, as is known in the art. The viscosity decreases when increasing the cutting speed as well as increasing the torque. ^ The starch material can be heated in a closed volume in the presence of a low concentration of water to convert the starch material into a pseudo-thermoplastic melt. The closed volume can be a closed container or the volume created by a sealing action of the feeding material as it happens in the screw of an extrusion equipment. The pressures generated in the closed vessel will include pressures due to the vapor pressure of the water as well as the pressures generated due to the compression of materials in the screw-barrel of the extruder. A chain cutting catalyst, which reduces the molecular weight by dividing the glycosidic linkages of the starch macromolecules which results in a reduction in the average molecular weight of the starch, can be used to reduce the viscosity of the pseudo-thermoplastic melt. Suitable catalysts include inorganic and organic acids. Suitable inorganic acids include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid and boric acid, as well as the partial salts of polybasic acids, for example NaHS0 or NaH2P04, etc. Suitable organic acids include formic acid, acetic acid, propionic acid, butyric acid, lactic acid, glycolic acid, oxalic acid, citric acid, itaconic acid, succinic acid and other organic acids known in the art including partial salts of polybasic acids . Hydrochloric acid, sulfuric acid and citric acid, including mixtures thereof, can be used beneficially in the present invention. The molecular weight reduction of the unmodified starch used can be by a factor of 2 to 5,000, and more specifically by a factor of 4 to 4,000. The catalyst concentration is in the range of 10"6 to 10 ~: moles of catalyst per mole of anhydro-glucose unit, and more specifically between Ol x 10" 3 and 5 x 10 ~ 3 moles of catalyst per mole of unit of starch anhydro-glucose. In figure 7 the starch composition is supplied in the apparatus 10 for production by electrospinning of starch filaments used in the manufacture of the flexible structure 100 of the present invention. The apparatus 10 comprises a structured and shaped housing 11 (arrow A) for receiving the starch composition 17 that can be held there and extruded (arrow D) into starch filaments 17a through the nozzle 14 of a head 13 of die An annular cavity 12 can be provided for circulating (arrow B and C) a heating fluid that heats the starch composition to the desired temperature. Other means for heating, well known in the art, such as those using electro-heating, pulsed combustion, water and steam heating, etc., can be used to heat the starch composition. The electric field can be applied directly to the starch solution, for example through an electrically charged probe, or to the housing 11 or to the extrusion die 13, or both. If desired, the molding member 200 can be charged electrically with the electrical charge opposite to the charges of the starch filaments that are extruded. Alternatively, the molding member can be connected to ground. The electrical differential can be from 5 kV to 60 kV and more specifically from 20 kV to 40 kV. The plurality of extruded starch filaments can then be deposited in the molding member 200 by moving in the direction of the MD machine at a distance from the apparatus 10. This distance should be sufficient to allow the filaments of starch to elongate and then dry, and at the same time maintaining a differential load between the starch filaments leaving the jet nozzle 14 and the molding member 200. For this purpose, a drying air stream can be applied to the plurality of starch filaments to cause the plurality of starch filaments to rotate at an angle. This may allow one to maintain a minimum distance between the jet nozzle 14 and the molding member 200 - to maintain a differential load therebetween, and at the same time to maximize the length of a portion of the filaments between the nozzle and the mouthpiece. molding member 200 - are the purposes of effectively drying the filaments. In such an arrangement, the molding member 200 can be positioned at an angle relative to the direction of the fiber filaments as they exit the jet nozzle 14 (arrow D in Figure 7). Optionally, attenuating air can be used in combination with an electrostatic force to provide the drawing force which causes the starch filaments to be attenuated, or stretched, before being deposited to the molding member 200. Figure 7A schematically shows an exemplary embodiment of the die head that is provided with an annular hole 15 encompassing the jet nozzle 14, and three other holes 16 equally spaced at 120 ° around the jet nozzle 14, for air extenuating. Of course, other mitigating air arrangements, as are known in the art, are contemplated in the present invention. According to the present invention, the starch filaments can have a size ranging from about 0.01 decitex to about 135 decitex, more specifically from about 0.02 decitex to about 30 decitex, and even more specifically from about 0.02 decitex to approximately 5 decitex. The starch filaments may have various cross-sectional shapes including, but not limited to, circular, oval, rectangular, triangular, hexagonal, cross-like, star-like, irregular and any combination thereof. A person skilled in the art will understand that such a diversity of shapes can be made by differential configurations of the die nozzles used to produce the starch filaments. Figure 10 shows schematically, without limitation, some possible cross-sectional areas of the starch filaments. The cross-sectional area of the starch filaments is an area perpendicular to the major axis of the starch filaments and is indicated by a perimeter formed by the outer surface of the starch filaments in a plane of the cross section. It is considered that the greater the surface area of the starch filament (per unit length or weight thereof), the greater the opacity of the flexible structure that constitutes the starch filaments. Therefore, it is considered that by maximizing the surface area of the starch filaments to increase the equivalent diameter of the starch filaments it may be beneficial to increase the opacity of the flexible structuring resulting from the present invention. One way of increasing the equivalent amount of the starch filaments comprises forming starch filaments having non-circular, multi-surface cross-sectional shapes. In addition, starch filaments do not need to have a uniform thickness or cross-sectional area across the length of the filament or a portion thereof., Fig. 10, for example, schematically shows a fragment of the starch filament having a differential cross-sectional area along its length. Such differential cross-sectional areas can be made, for example, by varying the pressure within a die or by changing at least one of the characteristics (such as speed, direction, etc.) of the attenuating air or air dried in a meltblowing process, or a combination of meltblowing and electrospinning process. Some filaments of starch may have (notches) distributed at certain intervals along the length of the filament or a portion thereof. Such variations in the cross-sectional area of the starch filaments along the length of the filaments are considered to encourage the flexibility of the filaments, they facilitate the ability of the filaments to entangle each other in the flexible structure 100 that is made and positively influence the smoothness and flexibility of the resulting flexible structure 100 that is made. The notches, or other beneficial irregularities of the starch filaments can be made by contacting the starch filaments with a surface having sharp edges or projections, as described below. The next step of the process comprises providing a molding member 200. The molding member 200 may comprise a drawn cylinder (not shown) or another pattern forming member such as a ribbon or band. The molding member 200 comprises a contact side 201 with the filament and a support side 202 opposite the contact side 201 with the filament. A fluid pressure differential (eg, a vacuum pressure that may be present below the belt or inside the drum) may force the starch filaments in the pattern of the molded member to form differentiable regions within the flexible structure that is elaborated. In the course of a process to develop the structure 100 of the present invention, filaments of starch are deposited on one side 201 in contact with the filaments. The second side 202 typically makes contact with the equipment, such as support rollers, guide rollers, a vacuum apparatus, etc., as required by the specific process. The side 201 in contact with the filaments comprises a three-dimensional pattern of projections or depressions or both. Typically, (though not necessarily), this pattern is not random and is repeated. The three-dimensional pattern of the side 201 in contact with the filaments may comprise a substantially continuous pattern (Figure 4), a substantially semi-continuous pattern (Figure 5), a pattern comprising a plurality of discrete protuberances (Figure 5) or any combination thereof. . When a plurality of starch filaments are deposited on one side 201 in contact with the filaments of the molding member 200, the plurality of flexible starch filaments are at least partially adapted to the molding pattern of the molding member 200. The molding member 200 may comprise a ribbon or band which is macroscopically monoplanar when it is in a reference plane X-Y, where a Z direction is perpendicular to the X-Y plane. Similarly, the flexible structure 100 can be considered as macroscopically monoplanar and located in a plane parallel to the X-Y plane. Perpendicular to the X-Y plane is the Z-direction along which a gauge, or thickness, of the flexible structure 100 extends, or elevations of the differential regions of the molding member 200 or of the flexible structure 100. If desired, a molding member 200 comprising a band can be executed as a pressure felt. A pressure felt suitable for use in accordance with the present invention may be made in accordance with the teachings of U.S. Patent Nos. 5,549,790, issued August 27, 1996 to Phan; 5,556,509, issued September 17, 1996 to Trokhan et al .; 5,580,423, issued December 3, 1996 to Ampuiski et al .; 5,609,725, issued March 11, 1997 for Phan; 5,629,052 issued May 13, 1997 to Trokhan et al .; 5,637,194, issued June 10, 1997 to Ampuiski et al .; 5,574,663, issued October 7, 1997 to McFarland et al .; 5,693,187 issued December 2, 1997 for Ampuiski et al .; 5,709,775 issued January 20, 1998 to Trokham et al .; 5,776,307 issued July 7, 1998 for Ampuiski et al .; 5,795,440 issued August 18, 1998 to Ampuiski et al .; 5,814,190 issued September 29, 1998 for Phan; 5,187,377, issued October 6, 1998 to Trokhan et al .; 5,846,379 issued December 8, 1998 for Ampuiski et al .; 5,855,739 issued on January 5, 1999 for Ampuiski et al .; and 5,861,082, issued January 19, 1999 to Ampuiski et al., the disclosures of which are incorporated herein by reference. In an alternative embodiment, the molding member 200 can be executed as a press felt, in accordance with teachings of U.S. Patent No. 5,569,358 issued October 29, 1996 to Cameron. A main embodiment of the molding member 200 comprises a resinous infrastructure 210 attached to a reinforcing element 250. The resinous infrastructure 210 may have a certain preselected pattern. For example, Figure 4 shows the substantially continuous infrastructure 210 having a plurality of openings 220 therethrough. In some embodiments, the reinforcing element 250 can be substantially fluid permeable. The fluid permeable reinforcement element 250 may comprise a woven mesh, or a perforated element, a felt or any combination thereof. The portions of the reinforcing element 250 aligned with the openings 220 in the molding member 200 prevent the starch filaments from passing through the molding member 200., and therefore reduce the appearance of pitting in the resulting flexible structure 100. If it is not desired to use a woven fabric for the reinforcing element 250, a non-woven element, mesh, net, press felt or a plate or film having a plurality of holes therethrough can provide adequate support and strength. from the infrastructure 210. The suitable reinforcement element 250 can be made in accordance with U.S. Patent Nos. 5,496,624, issued March 5, 1996 to Stelljes, et al., 5,500,277 issued March 19, 1996 to Trokhan et al., and 5,566,724, issued October 22, 1996 to Trokhan et al., whose descriptions are incorporated herein by reference. Various types of fluid permeable reinforcement elements 250 are described in several US patents, for example 5,275,700 and 5,954,097 whose descriptions are incorporated herein by reference. The reinforcement element 250 may comprise a felt, also referred to as a "press felt" as used in conventional papermaking. The infrastructure 210 can be applied to the reinforcing element 250, as described in U.S. Patents 5,549,790, issued August 27, 1996 to Phan; 5,556,509, issued September 17, 1996 to Trokhan et al .; 5,580,423, issued on December 3, 1996 for Ampuiski et al .; 5,609,725 issued March 11, 1997 to Phan .; 5,629,052 issued May 13, 1997 to Trokhan et al .; 5,637,194, issued June 19, 1997 to Ampuiski et al .; 5,674,663 issued on October 7, 1997 for McFarl ind et al .; 5,693,187 issued on December 2, 1997 for Ampuiski et al .; 5,709,775 issued on January 20, 1998 to Trokhan et al., 5,795,440 issued August 18, 1998 to Ampuiski et al., 5,814,190, issued September 29, 1998 to Phan; 5,817,377 issued October 6, 1998 to Trokhan et al .; and 5,846,379 issued December 8, 1998 for Ampuiski et al .; whose descriptions are incorporated herein by reference. Alternatively, the reinforcing element 250 can be impermeable to fluids. The fluid-resistant reinforcing element 250 may comprise, for example, a polymeric resinous material > identical to, or different from, the material used to make an infrastructure 10 of the molding member 200 of a present invention, a plastic material, a metal or any suitable natural or synthetic material, or any combination thereof A person skilled in the art will appreciate that the fluid impermeable reinforcing element 250 will cause the molding member 10, as a whole, also to be fluid-impermeable.It should be understood that the reinforcing element 250 may be partially fluid permeable and partially impervious to fluids, that is, a portion of the reinforcing element 250 may be fluid permeable while another portion of the reinforcing element 250 may be impermeable to fluids.All of the molding member 200 may be fluid permeable, fluid-impervious or partially fluid-permeable, in a partially fluid-permeable molding member 200, only a portion or portions of an area or macroscopic areas of the molding member 200 are fluid permeable. If desired, a reinforcing element 250 comprising a Jacquard fabric may be used. Illustrative tapes having a Jacquard weave can be found in U.S. Patent Nos. 5,429,686 issued on Apr. 4, 1995 to Chiu, et al .; 5,672,248 issued on 9/30/97 to Wendt, et al .; 5,746,887 issued on 5/5/98 to Wendt et al .; and 6,017,417 issued 1/25/00 to Wendt et al., the disclosures of which are incorporated herein by reference for the limited purpose of showing a major construction of Jacquard tissue. The present invention contemplates that the molding member 200 comprises a side 201 in contact with the filaments that contains a Jacquard weave pattern. Such a Jacquard weave pattern can be used as a forming member 500, a molding member 200, a pressing surface, etc. It is reported in the literature that a Jacquard fabric is particularly useful where one does not want to compress or print a structure in a narrowing, as typically happens with the transfer of a Yankee drying drum. In accordance with the present invention, one, several or all of the openings 220 of the molding member 200 may be "blind" or "closed" as described in U.S. Patent 5,972,813 issued to Polatr et al., on October 26, 199, the description of which is incorporated herein by reference. As described in the above-mentioned patent, polyurethane, rubber and silicone foams can be used to return to the fluid-impermeable openings 220. One embodiment of the molding member 200 shown in Figure 6 comprises a plurality of suspended portions 219 extending (typically laterally) from a plurality of base portions 211. The suspended portions 219 are raised from the reinforcing element 250 to form hollow spaces 215 within which the starch filaments of the present invention can be bent to form cantilevered portions 129., as described above with reference to Figure 3. The molding member 200 comprises suspended portions 219 which may be constituted of a multilayer structure formed by at least two layers (211, 212) joined in a face-to-face relationship ( figure 6). Each of the layers may comprise a structure similar to one of the various patents described above and incorporated herein by reference. Each of the layers (211, 212) can have at least one opening (220, FIGS. 4, 4A) and that extends between the upper surface and the lower surface. The bonded layers are positioned so that at least one opening of one layer overlaps (in the direction perpendicular to the general plane of the molding member 200) with a portion of the infrastructure of one layer, which portion forms the suspended portion 219 described in the above here. Another embodiment of the molding member comprises a plurality of suspended portions that can be made by a process of differential curing a layer of photosensitive resin, and another curable material, through a mask comprising transparent regions and opaque regions. Opaque regions comprise regions that have differential opacity, e.g., regions that have a relatively high opacity (non-transparent, e.g., black) and regions that have a relatively low partial opacity (i.e., that have some transparency). When the curable layer having a filament receiving side and a second opposing side are exposed to curing radiation through the mask adjacent the filament receiving side of the coating, the non-transparent regions of the first mask cover areas of the coating from the curing radiation they prevent the first areas of the coating from being cured through the full thickness of the coating. The partial opacity regions of the mask only partially cover second coating areas to allow the curing radiation to cure the second areas to a predetermined thickness less than the thickness of the coating (starting from the filament receiving side of the coating to the second side). of the same) . The transparent regions of the mask have third areas of the unprotected coating to allow the curing radiation to cure the third areas through the full thickness of the coating. Consequently, the uncured material can be removed from a partially formed molding member. The resulting hardened infrastructure has a side 201 in contact with the filaments formed on one side receiving filaments from the coating and a support side 202 formed from the second side of the coating. The resulting infrastructure has a plurality of bases 211 which comprise the support side 202 and which are formed from the third areas of the coating and a plurality of suspended portions 219 comprising the side 201 in contact with the coil and formed from second areas. of the coating. The plurality of bases may comprise a substantially continuous pattern, a substantially semi-continuous pattern, a discontinuous pattern or any combination thereof, as discussed above. The suspended portions 210 extended at an angle (typical, although not necessarily at about 90 °) form the plurality of bases and are spaced from the support side 202 of the resulting infrastructure to form gaps between the suspended portions and the support side 201 Typically, when a molding member 200 comprising a reinforcing element 250 is used, the hollow spaces 215 are formed between the suspended portions 219 and the reinforcing element 250, as best shown in Figure 6. The next step comprises depositing the plurality of pseudo-thermoplastic starch filaments on the side 201 in contact with the filaments of the molding member 200, as shown schematically in Figures 7 to 9, and causing the plurality of starch filaments to adapt at least partially to the three-dimensional pattern of the molding member 200. With reference to a modality shown schematically in Figure 7, before the outlet of the drawing unit, the starch filaments 17b are deposited on the three-dimensional filament contacting side 201 of a molding member 200. In a continuous industrial process, the molding member 200 comprises an endless band that is continuously moved in a direction of the MD machine, as shown schematically in Figures 7 to 9. The starch filaments can then be bonded together and they entangle each other through various conventional techniques. The disclosure of U.S. Patent No. 5,688,468 issued to Lu on November 18, 1997, discloses a process and apparatus for producing a spunbonded nonwoven web composed of small diameter filaments, and is incorporated herein by reference. as reference. In some embodiments, the plurality of the starch filaments must first be deposited not on the molding member 10, but on a forming member 500, as shown schematically in Figure 9. This step is optional and can be used to facilitate the uniformity in the basis weight of the plurality of starch filaments through a width of the structure 10 being processed. The shaping member 500 comprises a wire and is contemplated by the present invention 7, in an exemplary embodiment of FIG. 9, the shaping member 500 is moved in the machine direction to t of the rollers 500a and 500b. The shaping member is fluid permeable, and a vacuum apparatus 550 located below isis shaping member 500 and which applies a fluid pressure differential to the plurality of starch filaments placed therein encourages a more or less uniform distribution of the starch filaments through the receiving surface of the shaping member 500. If desired, the shaping member 200 can also be used to conform various irregularities in the starch filaments, particularly on the surface of the filaments. For example, a filament receiving surface of the shaping member may comprise a variety of cutting edges (not shown) structured to print still relatively soft starch filaments deposited therein, to create notches (shown schematically in Figure 11) or other irregularities in the starch filaments, which may be beneficial for the flexible structuring being processed, as described above. In the embodiment of Figure 9, the plurality of filaments can be transferred from the shaping member 500 to the shaping member 200 by any conventional means known in the art, for example by means of a vacuum shoe 600 which applies a pressure of vacuum which is sufficient to cause the plurality of starch filaments placed on the forming member 500 to separate therefrom and adhere to the molding member 200. It is contemplated that in the continuous process of making the flexible structure 100, the molding member 200 may have a linear speed that is less than that of the shaping member 500. The use of such speed differential at the transfer point is commonly known in papermaking techniques and can be used for what is termed "microcontraction" which is typically considered to be efficient when applied to wet coils of low consistency. U.S. Patent 4,440,597, the disclosure of which is incorporated herein by reference for the purpose of describing a main microcontraction mechanism, describes in detail the wet microcontraction. "Briefly, wet microcontraction involves the transfer of the coil that has a low fiber consistency from a first member (such as a foraminous member) to a second member (such as a fabric with an open tissue loop (which moves slower than the first member)., it is considered that if starch filaments can be formed and the plurality of starch filaments can be maintained in a sufficiently flexible condition by the transfer time from a relatively slow moving support (such as, for example, as the member 500). of forming) to a relatively faster moving support (such as, for example, the molding member 200), it is possible to effectively subject the plurality of starch filaments to microcontraction, whereby a reduction of the flexible structure 100 is realized. . The speed of the molding member 200 may be from about 1% to about 25% greater than that of the shaping member 500. Figure 9A shows one embodiment of the process according to the present invention, wherein the starch filaments can be deposited in the molding member 200 at an angle A which can be from 1 ° to 89 °, and more specifically, from about 5th to approximately 85 °. This embodiment is considered to be especially beneficial when using the molding member 200 having portions 219 suspended. Such "slanting" deposition of the starch filaments 17a to the molding member 200 causes the hollow spaces 215 formed between the suspended portions 219 and the reinforcing element 250 to be more accessible to the long and flexible starch filaments 17a and encourages the starch filaments are more easily filled with hollow spaces 215. Figure 9A shows filaments of starch 17A with the molding member 200 in two steps, so that both kinds of hollow spaces 219 - upstream hollow spaces 215a and hollow spaces downstream 215b - can benefit from the inclined deposition of the filaments to the molding member 200. Depending on the specific biometry of the molding member 200, particularly the geometry or orientation of these suspended portions 219, a downstream angle A may be the same as or different from the angle B upstream.

As soon as the plurality of starch filaments is placed on the side 201 in contact with the filament of the molding member 200, the plurality of filaments adapt at least partially to their three-dimensional pattern. In addition, various means can be used to cause or encourage the starch filaments to adapt to the three-dimensional pattern of the molding member 200. One method comprises applying a fluid pressure differential to the plurality of starch filaments. This method can be especially beneficial when the molding member 200 is fluid permeable. For example, a vacuum apparatus 550 placed on the support side 202 of the fluid-permeable molding member 200 can be positioned to apply a vacuum pressure to the molding member 200 and therefore the plurality of starch filaments placed on it. Under the influence of the vacuum pressure, some of the starch filaments may be bent in the openings 220 or the hollow spaces 215, or both, of the molding member 200 and may be adapted in some other way to the three-dimensional pattern of it. It is considered that all of the three regions of the flexible structure 100 may have generally equivalent basis weights. By folding a portion of the starch filaments into the openings 220, one can decrease the density of the resulting supports 120 relative to the density of the first printed regions 110. The regions 110 that do not bend in the openings 220 can be printed by compressing the flexible structure into a compression nip. If printed, the density of the printed regions 110 increases in relation to the density of the supports 120, and the density of the third region 130. The densities of the regions 110 do not deviate within the openings 220, and the The density of the third region 130 is greater than the density of the supports 120. The third region 130 will probably have an intermediate density to that of the printed region 110 and that of the supports 120. With reference still to FIG. IA, the structure 100 flexible according to the present invention can be considered to have three different densities. The region of highest density will be the 110 high density printed region. The printed region 110 corresponds in geometrical position to the infrastructure 210 of the molding member 200. The region of least density of the flexible structure 100 will be that of the supports 120, which corresponds in position and geometry to the openings 220 of the molding member 200. The third region 130, which corresponds to the synclinal folds 230 in the molding member 200, will have a density intermediate that of the supports 120 and the printed region 110. The "synclinal folds" 230 are surfaces of the infrastructure 210 having a Z direction vector component extending from the filament receiving side 201 of the molding member 200 to the support side 202 thereof. The synclinal folds 230 do not extend completely through the infrastructure 210, as do the openings 220. Therefore, the difference between a synclinal fold 230 and the openings 220 may be considered so that the opening 220 represents a through hole in the interior. the infrastructure 210, while a synclinal fold 230 represents a blind hole, a crack, crack, or notch in the infrastructure 210. The three regions of the flexible structure 100, according to the present invention, can be considered to be placed in three different elevations. As used herein, the elevation of a region refers to its distance from a reference plane (ie, the X-Y plane). By convention, the reference plane can be viewed as horizontal, where the elevational distance of the reference plane is vertical. The elevation of a particular region of the flexible structure 100 of starch filament can be, using any measuring device without suitable coring for such purpose, as is well known in the art. A particularly suitable measuring device is a non-contact laser displacement detector with a beam size of 0.3 x 1.2 millimeters and a range of 50 millimeters. The suitable displacement detectors lase: without contact are sold by Idee Company as model MX1A / B. Alternatively, a contact stylus calibrator, as is known in the art, can be used to measure the different elevations. Such stylet calipers are described in U.S. Patent 4,300,981 issued to Carstens, the disclosure of which is incorporated herein by reference. The flexible structure 100 according to the present invention is placed in the reference plane with the printed region 110 in contact with the reference plane. The supports 120 and the third region 130 extend vertically away from the reference plane. The differential elevations of the regions 110, 120 and 130 can also be formed using the molding member 200 having differential depths or elevations of its three-dimensional pattern, as schematically shown in Figure 5A. Such three-dimensional patterns have differential depths / elevations that can be processed in sanitized pre-selected portions of the molding member 200 to reduce their elevation. In addition, the molding member 200 comprises a curable material that can be made by using a three-dimensional mask. By using a three-dimensional mask constituted by the depressions / differential elevations of their depressions / projections, one can construct a corresponding infrastructure 210 that also has differential elevations. Other conventional techniques for shaping surfaces with differential elevation can be used for the above purposes. Reducing the possible negative effect of a sudden application of a fluid pressure differential by a vacuum apparatus 550 (figures 8 and 9), or a vacuum pick-up shoe 600 (figure 9), which may force some of the filaments or portions thereof throughout the length of the molding member 200 and thus lead to the formation of what are referred to as pitting in the resulting flexible structure, the support side of the molding member can be "textured" to form irregularities with a microscopic surface. These surface irregularities may be beneficial in some embodiments of the molding members 200, because they prevent the formation of a vacuum seal between the support side 202 of the molding member 200 and a surface of the papermaking equipment (such as as for example a surface of the vacuum apparatus), so that a "leak" is generated between them and therefore mitigate the undesirable consequences of a vacuum pressure application in a process through drying process air of the flexible structure 100 of the present invention. Other methods for generating such leaks are described in U.S. Patent Nos. 5,718,806; 5,741,402; 5,744,007; 5,776,311; and 5,885,421, the disclosures of which are incorporated herein by reference.

The leak can also be created using what is referred to as "differential light transmission techniques" as described in U.S. Patent Nos. 5,624,790; 5,554,467; 5,529,664; 5,514,523; and 5,334,289, the descriptions of which are incorporated herein by reference. The molding member can be made by applying a photosensitive resin coating to a reinforcing element having opaque portions, and then exposing the coating to the light of an activating wavelength through a mask having transparent and opaque regions, and also through the reinforcement element. Another way to create surface irregularities on the support side comprises the use of a textured shaping surface, or a textured barrier film, as described in U.S. Patents 5,364,504; 5,260,171; and 5,098,522, the disclosures of which are incorporated herein by reference. The molding member can be made by casting a photosensitive resin on and through a reinforcing element, while the reinforcing element is moved on a textured surface and after exposing the coating to the light of an activating wavelength. through a mask which has transparent and opaque regions. Such means, such as a vacuum apparatus 550 that applies voids (i.e., a negative pressure, less than atmospheric) to the plurality of filaments through the fluid permeable molding member 200, or a fan (not shown) that applies a positive pressure to the plurality of filaments, can be used to facilitate the deflection of the plurality of filaments in the three-dimensional pattern of the molding member. In addition, FIG. 9 schematically shows an optional step of the process of the present invention, wherein the plurality of starch filaments are superposed with a flexible sheet of material 800 comprising an endless band that travels around the rolls 800a and 800b and which makes contact with the plurality of filaments. That is, the plurality of filaments are interposed for a certain period of time, between the molding member 200 and the flexible sheet of material 800. The flexible sheet of material 800 may have a lower air permeability than that of the molding member 200, and in some embodiments it can be permeable to air. An application of a fluid pressure differential P to the flexible sheet 800 causes deflection of at least a portion of the flexible sheet towards, and in some cases within the three-dimensional pattern of the molding member 200, thereby obliging the plurality of starch filaments to closely match the three-dimensional pattern of the molding member 200. U.S. Patent 5,893,965, the disclosure of which is incorporated herein by reference, discloses a principle arrangement of a type of a process that uses the flexible sheet of material. Additionally or alternatively to the fluid pressure differential, mechanical pressure can also be used to facilitate the formation of the three-dimensional microscopic pattern of the flexible structure 100 of the present invention. Such mechanical pressure can be generated by any suitable press surface comprising, for example, the surface of a roll or the surface of a band. Figure 8 shows two exemplary embodiments of a pressurized surface. A pair or several pairs of press rolls 900a and 900b, and 900c and 900d, are used to force the starch filaments placed on the molding member 200 to more fully conform to the three-dimensional pattern thereof. The pressure exerted by the pressure rollers can be placed in phase, if desired, for example, the pressure generated between the rollers 900c and 900d can be greater than between the rollers 900a and 900b. Alternatively or additionally, an endless pressing band 950 that travels through the rollers 950a and 950b, it can be pressed against a portion of filament side 201 of the molding member 200, to print the flexible structure 100 therebetween. The pressing surface can be uniform or have a three-dimensional pattern by itself. In the latter case, the pressing surface can be used as an etching device to form a distinctive micropattern or projections or depressions, or both, in the flexible structure 100, cooperatively or independently of the three-dimensional pattern of the molding member 200. In addition, the pressing surface can be used to deposit a variety of additives, such as for example softeners and ink to the structure 200 that is made. Conventional techniques such as, for example, an ink roller 910 or a sprinkler device 920 can be used to directly or indirectly deposit various additives of the flexible structure 1200 that is made. The flexible structure 100 can optionally be reduced by the creping of the structure 100 of a rigid surface, and more specifically of a cylinder, such as, for example, a cylinder 290 schematically shown in Figure 9. The crease is carried out with a doctor blade 292, as is well known in the art. The crepe can be brought to J? C in accordance with U.S. Patent 4,919,756, issued April 24, 1992 to Sawdai, the description of which is incorporated herein by reference. In alternation to or additional, the reduction can be carried out by microccThis action, as described above. The flexible structure 100 that is typically reduced is more extensive to the machine direction than in the machine transverse direction and can be easily bent around the articulation lines formed by the reduction process, articulation lines which are generally they extend in the transverse direction of the machine, that is, across the width of the flexible structure 100. The flexible structure 100 which is not creased or otherwise reduced, is contemplated to be within the scope of the present invention. Various products can be made using the flexible structure 100 of the present invention. The resulting products can find use in filters for air, oil and water; vacuum cleaner filters; oven filters, facial masks; filters for coffee, tea or coffee bags; thermal insulation materials and sound insulation materials; non-woven materials for one-time use sanitary products such as diapers, feminine pads and incontinence articles; biodegradable textile fabrics for improved moisture absorption and wear softness such as microfiber or breathable fabrics; and a structured coil, electrostatically charged to collect and move dust, reinforcements and coils for hard grades of paper, wrapping paper, printing paper, newsprint, corrugated paper board and coils for tissue or tissue grades such as paper hygienic, and paper towels, sanitary napkins and tissue paper facial; for medical uses such as surgical gowns, wound recovery material, bandages, skin patches and sutures that dissolve by themselves; and for dental use such as dental floss and bristles for toothbrushes. The flexible structure may also include odor absorbing substances, termite repellents, insecticides, rodenticides and the like, for specific uses. The resulting product absorbs water and oil and can find use in oil cleaning or splashing water, or controlled water retention and release for agricultural or horticultural applications. The resulting starch filaments or fiber coils can also be incorporated into other materials such as saw dust, wood pulp, plastic and concrete to form composite materials which can be used as building materials such as walls, support beams , pressed boards, dry walls and backs and tiles for the roof; other medical uses such as castings, splints, and tongue-twisters, and on trunks in fires for decorative or burning purposes.

TEST METHODS A. Cut Viscosity The cutting viscosity of the composition is measured using a capillary rheometer (model Rheograph 2003, manufactured by Goettfert). The measurements are carried out using a capillary die having a diameter D of 1.0 mm and a length L of 30 mm (ie L / D-30). The die is attached to the lower end of the barrel, which is maintained at a temperature (t) ranging from 25 ° C to 90 ° C. A sample composition which has been preheated to the test temperature is loaded into the barrel section of the rheometer and substantially fills the barrel section (approximately 60 grams of sample are used). The barrel is maintained at the specified test temperature (t). If bubbles are formed on the surface after loading, compaction is used before the test is carried out to release the trapped air sample. A piston is programmed to push the sample from the barrel through the capillary die to a set of chosen speeds. As the sample progresses from the barrel through the capillary die, the sample experiences a pressure drop. An apparent shear viscosity is calculated from the pressure drop and the sample flow rate through the capillary die. Then the logarithm (apparent shear viscosity) is plotted against the logarithm (shear rate) and the graph is adjusted to a power law = K n_1, where K is a material constant, is the shear rate. The reported cut viscosity of the composition herein is an extrapolation at the cutting speed of 300 s "1 using the power law relationship.

B. Extensional Viscosity The extensional viscosity is measured using a capillary rheometer (model Rheograph 2003, manufactured by Goettfert). The measurements are carried out using a semi-hyperbolic die design with an initial diameter (Din? C? Al) of 15 mm, a final diameter (D? Nal) of 0.75 mm and a length (L) of 7.5 mm. The semi-hyperbolic shape of the die is defined by two equations. Where Z = the axial distance from the initial diameter, and where D (z) is the die diameter at a distance z from D, n, ciai; íp - l) zn = u + i: D (Zn). { initial and initial - 1 L Dfinal The die is attached to the lower end of a barrel, which is maintained at a fixed test temperature (t) which corresponds to the temperature at which the starch composition is to be processed. The test temperature (processing temperature) is a temperature above the melting point of a sample starch composition. The sample starch composition is preheated to the die temperature and loaded into the barrel section of the rheometer, and substantially fills the barrel section. If after the loading there are air bubbles to the surface, the compaction before carrying out the test is used to free the molten sample from the trapped air. A piston is programmed to push the sample from the barrel through the hyperbolic die at a chosen speed. As the sample progresses from the barrel through the orifice die, the sample experiences a pressure drop. An extensional apparent viscosity is calculated from the pressure drop and the flow velocity of the sample through the die according to the following equation: Extensional Viscosity = (delta P / extension speed / Eh) • 10"5), Where the extensional viscosity is in Pascal-seconds, delta P is the pressure drop of bars, the speed of extension and the flow velocity of the sample through the die seg "1, and Eh is the tension of Hencky, dimensionless The tension of Hencky is the time or background of dependent tension The tension experienced by a fluid element in a non-Newtonian fluid depends on its kinematic background, this is e ° = / e * (t) d t1 t The tension i J > Hencky (EJ is 5.99, defined by the equation: Eh = In [(D? N? C? Al / Df? NaJ 2] Visibility of apparent extension is reported as a function of the v-extension capacity of 250"1 using the power-law relationship.The detailed description of the extensional viscosity measurements using a semi-hyperbolic die is found in the patent of the United States No. 5,357,784, issued October 25, 1994 to Collier, the disclosure of which is incorporated herein by reference.

C. Molecular Weight and Molecular Weight Distribution The average molecular weight (Mw) weight and the molecular weight distribution (MWD) of the starch are determined by gel permeation chromatography (GPC) using a mixed bed column. The parts of the instrument are as follows: Pump: Waters Model 600E System controller: Waters Model 600E Autosampler: Waters Model 717 Plus Column: Mixed column A of 20 μm PL (the molecular weight of the gel varies from 1000 to 40,000,000) which has a length of 600 mm and internal diameter of 7.5 mm. Detector: Waters Model 410 differential refractometer, Waters Millennium ™ software GPC programming elements.

The column is calibrated with dextran standards having molecular weights of 245,000; 350,000; 480,000; 805,000; and 2,285,000. These dextran calibration standards are available from American Polymer Standards Corp., Mentor, OH. The calibration standards are prepared by dissolving the standards in the mobile phase to a solution of approximately 2 mg / ml. This solution is left to rest without alterations during the night. It is then gently shaken and filtered through a syringe filter (5 μm nylon membrane, Spartan-25, available from VWR) using a syringe (5 ml, Norm-Ject, available from VWR). The starch sample is prepared by first constituting a 40% by weight sample of starch in tap water with applied heat until the mixture gelatinizes. Then 1.55 grams of the gelatinized sample is added to 22 grams of the mobile phase to make a 3 mg / ml solution which is prepared by stirring for 5 minutes, placing the mixture in an oven at 105 ° C for 1 hour, Remove the mixture from the oven and cool to room temperature. The solution is filtered using a syringe and syringe filter as described above. The filtered standard or sample solution is retained by the autosampler to download previous test materials into a 100 μl injection loop and inject the present test material into the column. The column is maintained at 70 ° C. The sample eluted from the column is measured against the mobile phase background by a differential refractive index detector that is maintained at -50 ° C with the sensitivity range set to 64. The mobile phase is DMSO with 0.1% w / v LiBr dissolved in it. The flow rate is adjusted to 1.0 ml / minute and in isocratic mode (ie, the mobile phase is constant during the test). Each standard or sample is carried out through GPC three times, and the results are averaged. The molecular weight distribution (MWD) is calculated as follows: MWD = average molecular weight weight / average molecular weight number.

D. Thermal Properties The thermal properties of the present starch compositions are determined using a TA DSC-2910 instrument which has been calibrated with a metal indium standard, which has a melting (start) temperature of 156.6 ° C and a melting temperature of 6.80 calories per gram, as indicated in the chemical literature. The standard DSC operating procedure by the manufacturer's operating manual is the one used. Due to the production of volatile material (eg water vapor) from the starch composition during a DSC measurement, a high volume tray equipped with a 0-ring seal is used to prevent the escape of volatile fractions from the sample tray. The sample and an inert reference (typically an empty tray) are heated at the same speed in a controlled environment. When a real phase change or pseudo-phase change occurs in the sample, the DSC instrument measures the heat flow to or from the sample versus that of the inert reference. The instrument is interfaced with a computer to control the test parameters (ie, the heating / cooling rate) and to collect, calculate and report the data. The sample is weighed on a tray and closed with an O-ring and a lid. A typical sample size is 25-65 milligrams. The closed tray is placed on the instrument and the computer is programmed for thermal measurement as follows: 1. Balance at 0 ° C; 2. Hold for 2 minutes at 0 ° C; 3. Heat at 3 ° C / minutes up to 120 ° C; 4. Hold for 2 minutes at 120 ° C; 5. Cool at 10 ° C / minutes up to 30 ° C; 6. Balancing at room temperature for 24 hours, the sample tray can be removed from the DSC instrument and can be placed in a controlled environment at 30 ° C in this period; 7. Return the sample tray to the DSC instrument and equilibrate at 0 ° C; 8. Keep for 2 minutes; 9. Heat at 10 ° C / minute up to 120 ° C; 10. Hold for 2 minutes up to 120 ° C; 11. Cool to 10 ° C / minutes up to 30 ° C and equilibrate; and 12. Remove the used sample.

The computer calculates and reports the result of thermal analysis as a differential heat flux (H) versus temperature or time. Typically, the differential heat flux is normalized and reported on a basis by weight (ie, cal / mg). When the sample presents a pseudophase transition, such as a vitreous transition, a differential of the H plot versus time / temperature can be used to more easily determine a glass transition temperature.

E. Water solubility A sample composition is made by mixing the components with heat and agitation until a substantially homogenous mixture is formed. The molten composition is cast in a thin film by spraying it on a -Teflon ™ sheet and cooling to room temperature. The film is then completely dried (ie, without water in the film / composition) in an oven at 100 ° C. The dried film is then equilibrated at room temperature. The balanced film is milled into small granules. To determine the% solids in the sample, 2 to 4 grains of the milled sample are placed in a pre-weighed metal tray and the total weight of the tray and sample is recorded. The heavy tray and the sample are placed in a 100 ° C oven for 2 hours, then removed and weighed immediately. The% solids is calculated as follows: % solids = (weight of the ground sample and tray - weight of the tray) • 100 (first weight of the ground sample and tray - weight of the tray) To determine the solubility of the sample composition, 10 grams of the crushed sample was weighed in a 250 ml beaker. Deionized water is added to make a total weight of 100 grams. The sample and water are mixed in a plate and stirred for 5 minutes. After stirring, at least 2 ml of the stirred sample is poured into a centrifuge tube. Centrifuge for 1 hour at 20,000 g at 10 ° C. The supernatant of the centrifuged sample is taken and the refractive index is read. It is calculated as follows the% solubility of the sample: % Soluble solids = refractive index #) • 1000% solids F. Calibration Prior to testing, the film sample is conditioned at a relative humidity of 48% -50% and at a temperature of 22 ° C to 24 ° C until a moisture content of about 5% to about 16% is obtained. The moisture content is determined by TGA (thermogravimetric analysis). For thermogravimetric analysis, a high resolution thermogravimetric analyzer TGA2950 from TA Instruments is used. Approximately 20 mg of sample is weighed in a TGA tray. Following the manufacturer's instructions, the sample and tray are inserted into the unit and the temperature is increased at a rate of 10 ° C / minute to 250 ° C. The% moisture in the sample is determined using the weight lost and the initial weight as follows: humidity = initial weight - weight @ 250 ° C * 100% initial weight The preconditioned samples are cut to a size larger than the size of the bale used to measure the calibrator. The leg to be used is a circle with an area of approximately 20.2 cm2 (3.14 square inches). The sample is placed on a flat horizontal surface and confined between the flat surface and a loading shoe that has a horizontal loading surface, wherein the loading surface of the loading shoe has a circular area of approximately 20.0 cm2 (3.14 square inches) and a confining pressure of approximately 1.4 kPa (15 g / cm2 (0.21 psi)) is applied to the sample. The gauge is the resulting separation between the flat surface and the loading surface of the loading leg. Such measurements can be obtained in a VIR electronic thickness determiner model II, available from Thwing-Albert, Philadelphia, Pa. Calibrator measurements are repeated and recorded at least five times. The results are presented in thousandths of an inch. The sum of the recorded readings of the calibrator tests are divided by the number of recorded readings. The result is presented in thousandths of an inch.

NOMENCLATURE 10 APPARATUS TO PRODUCE STARCH FILAMENTS 11 ACCOMMODATION OF 10 12 CAVITY TO HEAT FLUID 13 TROQUEL HEAD 14 SPRAY NOZZLE 15 AIR (ANULAR) ORIFICE 16 ORIFICE (SEPARATE) OF AIR 17 STARCH COMPOSITION 17 STARCH FILAMENTS 100 FLEXIBLE STRUCTURE 110 FIRST REGIONS OF 100 120 SECONDS REGIONS OF 100 (SUPPORTS IN SOME MODALITIES) 130 THIRD REGIONS OF 300 115 SUBSTANTIALLY HOLLOWS (CAVIDADES) IN 100 (BETWEEN LOTS IN VOLADIZO AND THE FIRST REGIONS) 128 PORTION OF DOME 129 PORTIONS IN VOLADIZO DE 100 200 MEMBERS OF MOLDING 201 SIDE FILAMENT RECEIVER OF 200 202 SIDE OF SUPPORT OF 200 210 INFRASTRUCTURE 211 FIRST LAYER (IN A MULTI-LAYER STRUCTURE) 212 SECOND LAYER () 215 HOLLOW SPACES BETWEEN 219 AND 250 219 SUSPENDED PORTION 220 OPENING 230 SYNCLINAL FOLD 250 REINFORCEMENT ELEMENT 290 CYLINDER (ACCORDING) 292 'ACKNOWLEDGE BLADE 500 CONFORMATION MEMBER 550 VACUUM APPARATUS 600 VACUUM RECEPTION SHOE 800 FLEXIBLE MATERIAL SHEET (HYPOBARIC DEFLATION) 900a-900c PRESSURE ROLLERS 910 INK ROLL 920 SPRAYING DEVICE (SHOWER) 950 PRESSING BAND It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention

Claims (23)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A process for making continuous filaments of starch, the process is characterized in that it comprises the steps of: (a) providing a starch composition comprising having an extension viscosity of about 50 pascal -second to about 20,000 pascal -second; and (b) electroheating the starch composition, whereby starch filaments having a size from about 0.001 dtex to about 135 dtex are produced.

2. The process according to claim 1, characterized in that the step of providing a starch composition comprises providing a starch composition wherein the starch has an average molecular weight weight from about 1,000 to about 2,000,000.

3. The process in accordance with the claim 1, characterized in that in the electrospinning step, the starch composition has an inherent capillarity number of at least 0.05.

4. The process in accordance with the claim 2, characterized in that the starch composition has an inherent capillary number of at least 1.

5. The process in accordance with the claim 1, characterized in that the step of providing a starch composition comprises providing a starch composition wherein from about 20% to about 99% by weight is amylopectin.

6. The process according to claim 5, characterized in that the starch composition comprises from about 10% to about 80% by weight of the starch and from about 20% to about 90% by weight of active ingredients, and wherein the starch composition has a viscosity of extension from about 10 ° pascal -second to about 15,000 pascal-according to Jos.

7. The process according to claim 5, characterized in that the starch composition comprises from about 20% to about 70% by weight of the starch, and from about 30% to about 80% by weight of additives, and wherein the starch composition it has a viscosity of extension from about 200 pascal -second to about 10,000 pascal -second.

8. The process in accordance with the claim 5, characterized in that the starch composition has an extension viscosity of from about 200 pascal -second to about 10,000 pascal -seconds and an inherent capillarity number from about 3 to about 50.

9. The process according to claim 8, characterized in that the starch composition has the extensional viscosity from about 300 pascal -second to about 500 pascal -seconds and a number of capillarity from about 5 to about 30.

10. The process according to claim 1, characterized in that the step of providing a starch composition comprises providing a starch composition comprising from about 0.0005% to about 5% by weight of a high polymer having an average molecular weight of minus 50,000, the high polymer is substantially compatible with the starch.

11. The process in accordance with the claim I, characterized in that the step of providing a starch composition comprises providing the starch composition comprising an additive which is selected from the group consisting of plasticizers and diluents.

12. The process in accordance with the claim II, characterized in that the starch composition further comprises from about 5% to about 95% by weight of a protein, the protein comprises a protein derived from corn, a protein derived from soybeans, a protein derived from wheat or any combination of the same .

13. The process according to claim 1, characterized in that it also comprises a step of attenuating the filaments of starch with air currents.

14. A process for making a flexible structure comprising starch filaments, the process is characterized in that it comprises the steps of: (a) providing a starch composition having an extension viscosity of from about 100 pascal -second to about 10,000 pascal -seconds; (b) providing a molding member having a three dimensional filament receiving side and a supporting side opposite thereto, the filament receiving side comprising a substantially continuous pattern, a substantially semi-continuous pattern, a separate pattern and any combinations thereof; (c) electrospinning the starch composition, whereby a plurality of starch filaments are produced; and (d) depositing the plurality of starch filaments on the filament receiving side of the molding member, wherein the starch filaments conform to the three-dimensional pattern of the filament receiving side.

15. The process according to claim 14, characterized in that the step of providing a starch composition comprises providing a starch composition wherein the starch has an average molecular weight weight from about 1,000 to about 2,000,000, and wherein the starch composition it comprises a high polymer having an average molecular weight weight of at least 500,000.

16. The process in accordance with the claim 14, characterized in that the electrospinning step of the starch composition comprises electrospinning the starch composition through a die.

17. The process in accordance with the claim 16, characterized in that it also comprises the step of attenuating the starch filaments with air.

18. The process according to claim 14, characterized in that the step of providing a molding member comprises providing a structured molding member for continuously moving in the machine direction.

19. The process in accordance with the claim 14, characterized in that the step of providing a molding member comprises providing a molding member formed by a reinforcing element placed at a first elevation, and a resinous infrastructure attached to the reinforcing element in a face-to-face relationship and extending to outside from the reinforcement element to form a second elevation.

20. The process according to claim 19, characterized in that the molding member is fluid permeable and comprises a plurality of interwoven strands, a felt or any combination thereof.

21. The process according to claim 20, characterized in that the resinous infrastructure comprises a plurality of bases extending outward from the reinforcing element and a plurality of cantilevered portions extending laterally from the bases at the second elevation to form spaces gaps between the cantilevered portions and the reinforcement element, wherein the plurality of bases and the plurality of cantilevered portions form, in combination, a three-dimensional filament receiving side of the molding member.

22. The process in accordance with the claim 14, characterized in that the step of depositing the plurality of starch filaments on the filament receiving side of the molding member comprises applying a fluid pressure differential to the plurality of starch filaments.

23. The process according to claim 2, characterized in that the step of providing a starch composition comprises providing a starch composition comprising a high polymer.