Cotton sliver

Cottonseed oils Cotton sliver Cotton-wool blends... 

Woollen and worsted yams, unless dry spun contain significant amount of lubricating oil and are usually scoured in hank form in a continuous scouring machine. The hanks are transported through the scouring sets either by tape (Fig. 5-21) system or by battrices (Fig. 5-22). Usually, the sets have four bowls two scour bowls, one rinse bowl and a final bowl where acidification and moth proofing is carried out. There is a pair of squeeze roller between each bowl. The top roller is usually lapped with wool or cotton sliver and the bottom roller is made of metal. Pressure is applied to have an expression of about 60%. The characteristic features of the two types of machines are summerised in Table 5.2. It is normal to scour only 1-2... 

Cellulose substrates used in digestion studies were (ground) Solka Floe alpha cellulose, a non-nutritive fiber used for formulating animal diets (Gen. Biochem. Co.) Avicel, microcrystalline cellulose (American Viscose) heated milled Solka Floe (7) and (not ground) Whatman No. 1 filter paper, cotton sliver (25) and absorbent cotton (White Cross Co.). 

Hydrolysis of 1% cotton sliver 35 days at 29°C. (4 changes of enzyme). 

Ci units—action on cotton sliver for 24 hours at 40°C. (25). Hydrolysis of 6% Solka Floe, 42 days at 29°C. 

Eleven cotton celluloses and one of Valonia were studied. Among the twelve samples, the first nine cotton samples are in a randomly oriented fibril state (cotton sliver), EHC I and Hydrocellulose II are powders, and Valonia is in membrane pieces. They are listed and described below. 

Purified linters are used extensively in the USA for the prepn of NC, but longer fibers are preferred in Engl. During WWI, Engl also used material called slivers (Ref 1, 3, p 30), which was staple cotton in the form of unspun strips — an intermediate stage in the manuf of yam. Although more expensive than cotton waste, it yielded purer and more stable Cordite... 

Part II (1947). Studies of the treatment of cotton in sliver form. Effect of Syton spinning studies, with 18 references. 

The output fibers (along with the small pieces of yam and fabric) were double carded with a flat top card, the type of machine nsed for cotton and other short fibers. The purpose was to further open the fibers and to produce a lap for subsequent processing into sliver and yam. Just as before, material was ejected at the hckerin, and material was found to build-up on the flats (these have the same function as workers on the previous card). The fibers were processed on the machine a second time now 25% new acrylic fiber was added as a carrier. Even so, a coherent web was only possible with constant gniding of the material by hand. 

All S5uithetic fibers are produced as continuous filaments, either as yams or tows. Yams are fine enough to be woven or knitted directly, but cannot be intimately blended with other fibers on the principal conversion systems used for cotton and wool. For these conversion systems, staple fibers, made by cutting the much larger tows into short lengths, are needed. Tows can also be stretch-broken into slivers or tops, which can then be drawn out and twisted into spim yams. 

The next step is carding, where the cotton is passed between two surfaces set in close proximity to each other and covered with fine brush-like wires. The surfaces move in opposite directions or in the same direction at different speeds, resulting in a combing action that separates the fibers into a fine web. Getting the cotton to this opened condition causes most of the remaining finer trash to be removed. The fine web of fibers delivered from the card is condensed into a rope-like strand called card sliver and coiled into large cans. 

Flat Card n The type of card used for cotton fibers and for cotton-system processing. It is named for the flat wire brushes called flats that are assembled on an endless chain that partially surrounds the main cylinder. The staple is worked between the flats and cylinder, transferred to a doffer roll, and peeled off as a web that is condensed into a sliver. (Vincenti R (ed) (1994) Elsevier s textile dictionary. Elsevier Science and Technology Books, New York). Also see Flat. 

In his 1940 patent, Formhals described a method for making composite yarns by electrospinning onto existing cotton, wool or other pre-formed yam. It was also proposed that a sliver of fibers, such as wool, could be coated with the electrospun fibers before twisting the product into an intimately blended yarn [103]. 

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