The present invention relates to a method for producing single-hole and multi-hole ultra soft yarns, belonging to the technical field of fiber spinning, and making products derived therefrom.
During the exploitation of such yarns, the following three methods are known to introduce PVA (polyvinyl alcohol) fibers into the center of cotton yarns via a ring spinning system.
The first method is a spinning process in which PVA fibers are put into the core of cotton yarns on a spring frame, and PVA spun yarns are embedded into the streams of cotton fibers in a drafting zone during spinning. Since the cotton fibers in the outer sheath are likely to cluster into bundles during the weaving process, PVA fibers are unevenly spread on the surface of the yarns, resulting in uneven thickness of the yarns and thus insufficient hollowness and softness of towels made of such yarns.
The second method is a spinning process in which PVA fiber slivers (formed by carding) are put into the center of cotton slivers (formed by carding) in a drawing process of a spinning system for purpose of blending. It is unable to ensure that PVA fibers will be evenly wrapped by cotton fibers to form a hollow structure, even if the fibers are evenly blended in this process.
The third method is a process in which PVA slivers are embedded into the center of cotton slivers at a feeding end of the drafting zone of a roving frame, twisted on the roving frame, and then spun. After tests and a number of improvements, this method is regarded as the most hopeful method for achieving hollow PVA. However, only a single-hole hollow structure may be formed due to the restriction of the process.
The present invention provides a method for successively putting water soluble fibers (e.g., PVA) fibers into finish fibers (e.g., cotton fibers) to produce a hollow and ultra soft structure, by putting water soluble slivers into the center of a multi-hole feeder with multiple cotton fiber slivers arranged around the water soluble fiber in a pre-drawing process via a multi-hole sliver feeder. Once a fiber having a single centrally positioned PVA is produced, multiple single PVA fibers can be combined to provide a fiber having multiple water soluble fibers. In addition, fibers having multiple water soluble fibers can be further combined to provide a fiber having an increased number of water soluble fibers, which can subsequently be dissolved. Accordingly, the present invention provides a method of forming a multi-hole fiber.
According to one aspect of the processes described herein, a method of producing soft yarns comprises the steps of providing a plurality of finish fibers and providing a water soluble fiber. A drawing tool is provided. In a further aspect, the drawing tool is either a single or multi hole drawing tool. The plurality of finish fibers and the water soluble fiber(s), depending on the configuration of the drawing tool introduced into respective holes of the single or multi-hole drawing tool with the finish fibers arranged around the water soluble fiber(s). The finish fibers and the water soluble fiber or fibers are drawn through the drawing tool to form a combined fiber, the combined fiber having the water soluble fiber(s)surrounded by the finish fiber.
In a further implementation, a plurality of the combined fibers are provided. The plurality of the combined fibers are drawn to form a multi-combined fiber, the multi-combined fiber having multiple water soluble fiber surrounded by the finish fiber. The multi-combined fiber is then roved.
According to a further aspect, the multi-combined fiber is exposed to water to remove the water soluble fiber.
According to another aspect, the finish fiber is cotton, a cotton/polyester blend, or another cotton based fiber blend.
According to a further aspect, the water soluble fiber(s) are PVA.
According to another aspect, the drawing tool includes six holes arranged about a central seventh hole.
According to a yet further aspect, the introducing step includes the steps of passing the water soluble fiber into the central seventh hole and the finish fibers into the other six holes.
According to a yet further aspect, the method includes the step of providing a plurality of the multi-combined fibers. The plurality of the multi-combined fibers are drawn to form a second order multi-combined fiber, the second multi-combined fiber having multiple water soluble fiber surrounded by the finish fiber
According to a further aspect, method of manufacturing a cloth is provided that includes the step of weaving the cloth using at least one yarn produced by the methods disclosed above.
According to a further aspect, a cloth is provided that includes at least one yarn produced by the methods disclosed above.
According to a further aspect, a towel is provided that includes at least one yarn produced by the methods disclosed above.
By way of overview and introduction, and with reference to the processes described in
At steps 110 and 112, the materials that are to be blended to form the yarn are selected. At step 112, cotton fibers are selected.
In an alternative implementation the cotton fibers are a cotton polyester bend. For example, the cotton fibers are 50% cotton and 50% polyester. In a further implementation, the respective amounts of cotton and polyester are selected based on under preference, end product characteristics, manufacturing restraints or constraints, or other factors. In yet a further configuration, the cotton fiber include one or more additional components beyond polyester.
As one example, the physical indexes of the cotton fibers can be 29 mm or more in length, Micronaire A, short fiber content 10% or less. At step 110, a water soluble fiber is selected. As one example, the water soluble fiber can be PVA fibers having the following characteristics: body length: 38 mm; fineness: 1.33 dtex; dissolution temperature: 90° C. or less. It is desirable to select cotton fibers within the index disclosed or relatively close thereto because if the cotton fibers are far out of the indexes, there is a possibility that cohesion between the cotton fibers during the dissolution of PVA cannot be ensured. As a result, monofilaments can fall off from the yarns and molt rate of towels thus becomes high.
The production process 100 includes two main steps: (1) PVA pre-drawing slivers and cotton card slivers are spun, respectively; and the cotton fiber card slivers and the pre-drawing PVA slivers are fed into an additional 7-hole sliver feeder (see
One example of the process flow is shown in the table below:
Water-soluble fibers: FA002 Disk Plucker→A006B Automatic Blending Machine→A092A Double Hopper Feeder→A076E Lapper→A186D Carding Machine→FA304 Pre-drawing Machine
Cotton Fibers: FA002 Disk Plucker→A006B Automatic Blending Machine→FA104 Step Cleaner→A092A Double Hopper Feeder→A076E Lapper→FA201 Carding Machine→FA304 Pre-drawing Machine
The arrangement of the first passage drawn sliver and PVA is: cotton, cotton, cotton, PVA, cotton, cotton, cotton (see, for example,
At steps 114 and 116, the water soluble fibers and cotton fibers, respectively, undergo picking operations. Due to different characteristics of the cotton fibers and the PVA water-soluble fibers, the cotton fibers are blended in two hoppers, with two positions for opening and cleaning, and the PVA fibers are blended in two hoppers, with one position for opening and cleaning. The combined beater is a three-blade combined beater. If the PVA fibers are beaten too much, the fibers may be damaged and kinked. Therefore, as one example, the speed of the combined beater is approximately 1000 rpm/min for the cotton fibers and approximately 820 rpm/min for the PVA fibers, and the gauge between grid bars is minimized to reduce the amount of noils. As one example, the weight of a cotton lap is approximately 400 g/m, and the weight of a PVA fiber lap is approximately 380 g/m.
At steps 118 and 120, the water soluble fibers and cotton fibers, respectively, undergo picking operations. During picking, the PVA fibers can be treated by metal card clothing. To avoid congesting the card clothing, the speed of taker-in is approximately 920 rpm/min during cotton spinning and is approximately 790 rpm/min during PVA fiber spinning. The speed ratio of cylinder to taker-in is approximately 1.7:1 during cotton spinning and is approximately 2.2:1 during PVA fiber spinning. The purpose is to facilitate the transfer of fibers and to reduce damage to the fibers in order to avoid the generation of short fibers. Some gauges are adjusted according to different fibers as shown in the following table:
The unit of those mentioned above is mil.
At steps 122 and 124, the water soluble fibers and cotton fibers, respectively, undergo drawing operations. After these drawing operations, the cotton fibers and water soluble fibers undergo an additional drawing operation at step 128 to blend the fibers, as discussed in more detail below.
A blend ratio for the cotton slivers and the water soluble slivers is selected. As one example, the water soluble fiber (e.g. PVA) is approximately 5% to 30%, and the cotton is approximately 70%-95%. After many tests, an acceptable yarn blending ratio is defined in this range. If the content of PVA is much greater than 30%, the strength of the yarns is too low, resulting in a high molt rate when in use and affecting the wrapped effect of the PVA fibers by the cotton fibers. If the content of PVA is much less than 5%, the single-hole effect provided by the dissolving of the water soluble fiber is insufficient and it is unable to achieve ultra-soft, highly bulky and high absorption effects.
At step 128, the cotton fibers and water soluble fibers undergo a drawing process to blend the fibers such that the cotton fibers are arranged around and surrounding the water soluble fiber. As shown in
In one example, the three-up-three-down press bar drafting process is utilized. When breaker slivers are fed, the cotton and the PVA fibers are fed into an additional 7-hole sliver feeder 200 during a breaker-drawing process, with all the cotton fibers 202 in the outer layer and the water-soluble fibers 204 in the inner layer. For both the cotton fibers and the water-soluble fibers, the roller gauge can be approximately 12 mm×20 mm, and the spacer of the press bars is approximately 2.0 mm, for the purpose of enhancing the control on fibers.
In a particular implementation where the multi-hole yarn drawing tool is employed a step 128′, a second drawing process is performed in which multiple combined yarns, each having a single central water soluble fiber, are drawn together to provide a combined yarn having multiple water soluble fibers.
Multiple combined yarns that were produced as a result of step 128 can be combined to provide a multi-water soluble yarn. As shown in
At step 128″, a third drawing process can be performed in which multiple combined yarns, each having a multiple water soluble fibers, are drawn together to provide a combined yarn having an even higher number of water soluble fibers. Multiple combined yarns that were produced as a result of step 128′ can be combined to provide a multi-water soluble yarn. As shown in
As can be seen in
At step 130, the combined cotton and water soluble fibers undergo a roving process. During the roving process, a three-roller double-apron drafting can be utilized. The roving amount can be approximately 5-8 g per 10 m, and the roller gauge can be approximately 26.5 mm×33.5 mm.
The dissociated fibers are controlled in the drafting zone. Roving twist factor is defined as 70-90 based on the different proportions of the PVA fibers, the spinning back region process, and other conditions.
At step 132, the combined cotton and water soluble fibers undergo a spinning operation. According to the roving amount and the density of fine yarns, different drawing ratios and twist factors are designed. In one example, the density of fine yarns is 40S-6S. According to the density of fine yarns and the blending ratio, the twist factor is selected from approximately 260 to 400. After drawing the density of fine yarn is approximately 1.20-1.42, and the roller surface gauge is adjusted to approximately 21 mm×28 mm.
At step 134, the combined cotton and water soluble fibers undergo a winding process. The process principle of winding is “small tension, low speed”. In order to reduce hairiness and decrease the breaking rate, low speed and small tension are set. A capacitive electronic yarn clearer is used to improve the joint efficiency of the air splicer and reduce the yarn defects. In order to ensure the yarn strength and the moisture regain, the workshop temperature is controlled at approximately 28° C.-32° C., the relative humidity is controlled at approximately 65% -75%, and the winding speed is designed at approximately 900 m/min, all of which enable a better compromise between productivity and quality of cheeses.
Accordingly, a fiber 300 consisting of cotton fibers surrounding 302 a water soluble fiber 304 is provided as shown in
Six cotton fibers and one water-soluble fiber are fed into a breaker-drawing frame, with the cotton fibers being evenly spread around the water-soluble fiber to completely wrap the water-soluble fiber. In such a feeding mode, the cotton fibers are in the outer layer and the water-soluble fiber in the inner layer. Subsequently, by drawing and drafting, the water-soluble fiber is further dispersed in the cotton fibers. When the water soluble fibers are dissolved, multiple fine voids are formed at the locations of the water soluble fibers.
The following chart illustrates differences and performance improvements between the yarn of the present invention and prior art yarns.
Performance comparison between yarns obtained by the present invention and yarns obtained by the prior art
Performance comparison between yarns obtained by the according to the multi-hole configuration and yarns obtained by the prior art.
In one or more implementations, the method described herein is used to manufacture cloth that functions as a precursor for various articles, such as ultra soft towels. Accordingly, card slivers are produced from cotton fibers by picking and carding and pre-drawing silvers are produced from PVA fibers by picking, carding and pre-drawing. The cotton fiber card slivers and the pre-drawing PVA silvers are fed into an additional 7-hole sliver feeder (see
In a further implementation, such as where a multi year drawing tool us used, the yarns are then feed through additional drawing steps which combined the single water soluble fiber yarn into a yarn having multiple water soluble fibers surrounded by cotton fibers (or composite cotton fibers formed at least partially of polyester). When towels made of such yarns are placed into hot water, PVA fibers are dissolved to form a single-hole ultra soft cotton ring structure.
In yet another implementation, grey cloth is produced from either the single or multi-hole ultra soft yarn via a towel loom, and then fed into a combined desizing-scouring machine where PVA fibers are dissolved in hot water at 40° C.-100° C., and the PVA is completely removed by multiple times of washing. The grey cloth, which is removed off PVA fibers by washing, is subjected to scouring and bleaching, dyeing, soap boiling, softening, drying, stitching and finishing to produce a single or multi-hole ultra soft towel.
A finished towel made of such single or multi-hole ultra soft yarns is lightweight, plump and flexible, and can keep the softness for a long period of time. A towel made of such single or multi-hole ultra soft yarns is lighter, and higher in absorbance. Such single or multi-hole ultra soft yarns are preferred raw materials for weaving towels. A high-quality towel made of such single or multi-hole ultra soft yarns is bounded with fine satin, exhibiting high taste.
This application claims benefit of U.S. patent application Ser. No. 15/270,433, entitled METHOD FOR PRODUCING MULTI-HOLE ULTRA SOFT YARNS, filed on Sep. 20, 2016; U.S. patent application Ser. No. 15/270,346, entitled METHOD FOR PRODUCING SINGLE-HOLE ULTRA SOFT YARNS, filed on Sep. 20, 2016; and U.S. Provisional Application No. 62/355,581, entitled METHOD FOR PRODUCING SINGLE-HOLE ULTRA SOFT YARNS AND METHOD FOR PRODUCING MULTI-HOLE ULTRA SOFT YARNS, filed on Jun. 28, 2016, which are hereby incorporated by reference in their entirety.
Number | Date | Country | |
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62355581 | Jun 2016 | US |