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A method for stretch breaking fibers to produce a staple yarn and operating a staple fiber spinning machine that enables the production of a plurality of products of lot size smaller than a large denier tow product. The process includes at least two break zones and a consolidation zone downstream fr

A method for stretch breaking fibers to produce a staple yarn and operating a staple fiber spinning machine that enables the production of a plurality of products of lot size smaller than a large denier tow product. The process includes at least two break zones and a consolidation zone downstream from a second break zone to form a staple yarn. The filaments are broken in a second break zone downstream from the first break zone by increasing the speed of the fiber fed into the process.

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It is claimed: 1. A stretch-break process for producing a staple yarn from fiber, comprising filaments fed into a continuous operation, comprising: breaking the filaments in a first break zone by increasing the fiber speed within a first break zone length L1 at a first speed ratio D1 greater than o

It is claimed: 1. A stretch-break process for producing a staple yarn from fiber, comprising filaments fed into a continuous operation, comprising: breaking the filaments in a first break zone by increasing the fiber speed within a first break zone length L1 at a first speed ratio D1 greater than or equal to 2; breaking the filaments in a second break zone located downstream from the first break zone by increasing the fiber speed within a second break zone length L2 at a second speed ratio D2 greater or equal to 2; wherein a relationship (D2-1)/(D1-1) ranges from 0.15 to 2.5, and wherein a relationship L2/L1 ranges from 0.2 to less than 0.4; and consolidating the fiber in a consolidation zone downstream from the second brake zone to form a staple yarn. 2. A stretch-break process for producing a staple yarn from fiber, comprising filaments fed into a continuous operation, comprising: breaking the filaments in a first break zone by increasing the fiber speed within a first break zone length L1 at a first speed ratio D1 greater than or equal to 2, wherein the first break zone length is greater than or equal to 20.0 inches; breaking the filaments in a second break zone located downstream from the first break zone by increasing the fiber speed within a second break zone length L2 at a second speed ratio D2 greater than or equal to 2; wherein a relationship (D2-1)/(D1-1) ranges from 0.15 to 2.5, and wherein a relationship L2/L1 ranges from 0.2 to 0.6, and L1 is at least 20.0 inches; and consolidating the fiber in a consolidation zone downstream from the second brake zone to form a staple yarn. 3. A process as recited in claim 2 wherein the relationship (D2-1)/(D1-1) comprises a range of 0.2 to 2.0 and the relationship L2/L1 has an upper limit that is less than 0.4. 4. A process as recited in claims 1 and 2, further comprising drawing the fiber in a draw zone upstream from the first break zone by increasing the fiber speed within a predetermined draw zone length. 5. A process as recited in claim 4, wherein drawing the fiber comprises heating the fiber. 6. The process of claim 5, wherein the filaments fed into the operation are from the group comprising undrawn or partially drawn bicomponent filament structures and biconstituent filament structures. 7. A process as recited in claim 4, further comprising drafting the fiber in a draft zone upstream from the consolidation zone. 8. A process as recited in claim 7, further comprising feeding additional fiber into the process upstream of a zone selected from the group consisting of the first brake zone, the second break zone, the draft zone, and the consolidation zone. 9. A process as recited in claim 8, wherein feeding additional fiber comprises feeding a first additional fiber into the process at the upstream end of the first break zone and feeding a second additional fiber of continuous filaments into the process at the upstream end of the consolidation zone. 10. A process as recited in claims 1 and 2, further comprising drafting the fiber in a draft zone upstream from the consolidation zone. 11. A process as recited in claims 1 and 2, further comprising drafting the fiber in a draft zone, which is coincident with the consolidation zone. 12. A process as recited in claims 1 and 2, further comprising annealing the fiber in an annealing zone by heating the fiber within a predetermined annealing zone length. 13. The process of claim 12, wherein the filaments fed into the operation comprise partially drawn and fully drawn crimped structures. 14. A stretch-break process for producing a staple yarn from fiber comprising filaments fed into a continuous operation comprising: breaking the filaments in a first break zone between cylindrical entrance nip rolls and exit nip rolls, the exit nip rolls each having ends with a width therebetween, increasing the fiber speed within a first break zone length L1 at a first speed ratio D1 greater than or equal to 2 thereby creating a fiber having a core of closely gathered filaments and loose filament ends extending from the core; gathering the loose filament ends in the first break zone and adjacent the exit nip rolls and directing them toward the fiber core so the loose ends in all directions around the core are constrained to be within a distance from the center of core of not greater than the distance of the center of the core from each respective end of the exit rolls for the first break zone; breaking the filaments in a second break zone located downstream from the first break zone by increasing the fiber speed within a second break zone length L2 at a second speed ratio D2 greater than or equal to 2 and wherein a relationship (D2-1)/(D1-1) ranges from 0.15 to 2. 5, and wherein a relationship L2/L1 ranges from 0.2 to 0.6; and consolidating the fiber in a consolidation zone downstream from the second break zone to form a staple yarn. 15. The process of claim 14, wherein gathering the loose filament ends comprises passing the fiber through a bore and creating a spiral fluid flow path in the bore to loosely wrap the loose filament ends around the core. 16. The process of claim 14, wherein gathering the loose filament ends comprises passing the fiber through a trough having side walls to loosely contain around the core the loose filament ends extending laterally toward the nip roll ends. 17. The process of claim 14, wherein breaking the filaments in a second break zone occurs between cylindrical entrance nip rolls and exit nip rolls, the exit nip rolls of the second break zone each having ends with a width therebetween, creating a fiber in the second break zone having a core of closely gathered filaments and loose filament ends extending from the core; and further comprising gathering the loose filament ends in the second break zone and adjacent the exit nip rolls of the second break zone; and directing the loose filament ends toward the fiber core such that the loose filament ends in all directions around the core are constrained to being within a distance from the center of core of not greater than the distance of the center of the core from each respective end of the exit nip rolls for the second break zone. 18. A stretch-break process for producing a staple yarn from fiber, comprising filaments fed into a continuous operation, comprising: breaking the filaments in a first break zone by increasing the fiber speed within a first break zone length L1 at a first speed ratio D1 greater than or equal to 2, the first break zone having a length greater than 20.0 inches; breaking the filaments in a second break zone located downstream from the first break zone by increasing the fiber speed within a second break zone length L2 at a second speed ratio D2 greater than or equal to 2, wherein the relationship (D2-1)/(D1-1) ranges from 0.15 to 2. 5, and the relationship L2/L1 ranges from 0.2 to 0.6, forming a fiber of discontinuous filaments having an average length "avg"; and consolidating the fiber in a consolidation zone downstream from the second break zone to form a staple yarn by passing the fiber through the nip of a pair of cylindrical rolls and then through a first bore in a first nozzle that provides a jet of fluid through a channel into the first bore in a first spiral direction around the fiber to twist the loose filaments around the fiber core, the first nozzle having an entrance end adjacent the nip of said feed rolls, and then passing the fiber through a second bore in a second nozzle that provides a jet of fluid through a channel into the second bore in a second spiral direction around the fibers to false twist the fiber core, the second spiral direction opposite from the first, the channel in the second bore of the second nozzle spaced from the channel in the first bore of the first nozzle by a distance "a", where 0.5 avg<a<2.0 avg. 19. The process of claim 13, wherein the crimped structures comprises partially drawn or fully drawn bicomponent filament structure and biconstituent filament structures. 20. The process of claims 1, 2, 8, 9, 14 and 18 wherein the filaments comprise one or more materials selected from the group consisting of aramid, spandex, nylon, polyester and fluoropolymer. 21. The process of claim 20 wherein the polyester is 2GT or 3GT. 22. The process of claims 1, 2, 8, 9, 14 and 18 wherein the filaments comprise continuous filaments that have less than 10% elongation to break. 23. The process of claims 1, 2, 8, 9, 14 and 18 wherein the filaments comprise elastic filaments having an elongation to break greater than 100% and an elastic recovery of at least 30% from an extension of 50%. 24. The process of claims 1, 2, 8, 9, 14 and 18 wherein the filaments have a visual difference in color, the colors of the filaments excluding neutral colors have a lightness greater than 90%, and the colors of different colored filaments have a color difference of at least 2.0 CIELAB units (the lightness and color difference being measured according to ASTM committee E12, standard E-284).