Blended fabrics

Staple. PET staple is widely used in 100% polyester or cotton-blend fabrics for apparel. Typical cotton-blend polyester staple fibers have a linear... 

Traditional uses for ramie have been for heavy industrial-type fabrics such as canvas, packaging material, and upholstery. Increased production of the fiber in Asia, particularly China, has promoted the use in blended fabrics with silk, linen, and cotton which can now be found on the market. 

Considerable effort is being made (ca 1993) to develop satisfactory flame retardants for blended fabrics. It has been feasible for a number of years to produce flame-resistant blended fabrics provided that they contain about 65% or more ceUulosic fibers. It appears probable that blends of even greater synthetic fiber content can be effectively made flame resistant. An alternative approach may be to first produce flame-resistant thermoplastic fibers by altering the chemical stmcture of the polymers. These flame-resistant fibers could then be blended with cotton or rayon and the blend treated with an appropriate flame retardant for the ceUulose, thereby producing a flame-resistant fabric. Several noteworthy finishes have been reported since the early 1970s. 

Phosphonium Salt—Urea Precondensate. A combination approach for producing flame-retardant cotton-synthetic blends has been developed based on the use of a phosphonium salt—urea precondensate (145). The precondensate is appUed to the blend fabric from aqueous solution. The fabric is dried, cured with ammonia gas, and then oxidized. This forms a flame-resistant polymer on and in the cotton fibers of the component. The synthetic component is then treated with either a cycUc phosphonate ester such as Antiblaze 19/ 19T, or hexabromocyclododecane. The result is a blended textile with good flame resistance. Another patent has appeared in which various modifications of the original process have been claimed (146). Although a few finishers have begun to use this process on blended textiles, it is too early to judge its impact on the industry. 

In addition to carbon and glass fibers ia composites, aramid and polyimide fibers are also used ia conjunction with epoxy resias. Safety requirements by the U.S. Federal Aeronautics Administration (FAA) have led to the development of flame- and heat-resistant seals and stmctural components ia civiUan aircraft cabias. Wool blend fabrics containing aramids, poly(phenylene sulfide), EDF, and other inherently flame-resistant fibers and fabrics containing only these highly heat- and flame-resistant fibers are the types most frequently used ia these appHcations. 

A second general approach to achieve reduced wet pickup is based on the use of the vacuum slot technology (15,16). In this case the fabric may be padded conventionaUy, but is then mn against a vacuum slot (17). This vacuum slot removes a certain amount of water solution from the fabric, so that a reduced level of wet pickup is achieved prior to drying. A lower level of wet pickup is achieved on blend fabrics than it is on 100% ceUulosics using the vacuum slot technology. 

Other fibers blended with polyesters in numerous blended fabrics requke alternative methods of preparation. Generally, the scouring and bleaching procedures used for these blends are those employed for the primary component of the blended fiber or for the component that most influences aesthetic appearance. 

Enzymatic Polishing of Jnte/Cotton-blended Fabrics (Sreenath et al.,... 

Figure 6.26 Flow schematic of a three-stage feed-and-bleed ultrafiltration system used to recover poly(vinyl alcohol) (PVA) sizing agents used in the production of cotton/synthetic blend fabrics [28]...

With a few exceptions, sulfur dyes [1] are employed to dye cellulosic fibers. The main applications are the dyeing of corduroy, velveteen, denim articles, twill work clothes, tarpaulins, and backpack fabrics. The dyeing of the cellulosic fiber component of blended fabrics (polyester/cotton blends above all) is increasingly important. 

Dyes based on these compounds possess, in addition to good lightfastness, excellent wetfastness and are usually neutral-dyeing on wool. This, although of no importance for dyeing pure wool, plays an important role in dyeing blended spun yam and blended fabrics of wool and cotton or wool and viscose staple. The neutral-dyeing acid dye can be used in combination with direct dyes (union wool recipes). Examples are C.I. Acid Yellow 56, 24825 [6548-24-9] (17), and C.I. Acid Red 154, 24800 [6507-79-5] (18 R = CH3). 

The main applications are piece dyeing, which is important for the dyeing of the CEL component of PES-CEL blended fabrics, yarn dyeing, and dyeing of flock, card, sliver, etc., for blended yams with wool and man-made fibers. 

Thermosol Process. The most important continuous dyeing process for PES fibers is the thermo sol process. It is applied primarily to PES-CEL blends (see Section 4.12.4). The thermosol process consists of four individual steps (1) Padding of the dye liquor on the fabric, (2) Drying, (3) Fixing of the dyes in the fiber, (4) Aftertreatment. The four individual steps usually follow one another in one pass. Systems also exist that include the subsequent overdyeing of the cellulose component in blended fabrics [e.g., by using the pad steam technique (see Section 4.1.1)]. 

If the reactants are applied uniformly, the absence of migration allows a lower average level of treatment to assure a given level of performance in the finished fabric. Experimental evidence for such an improved efficiency has been reported by several investigators (4, 13, 14). Results in our laboratories have confirmed a higher resin efficiency for polyester-cotton blend fabrics treated at low wet pick-up by controlled applica-... 

In conventional continuous wet finishing, a rather dilute, usually from 4 to 8% solids solution or dispersion of the chemicals Is prepared. The fabric Is then Immersed in this solution. The wet fabric Is passed through pad rollers to squeeze out the excess solution. Despite the squeezing, a cotton fabric usually retains 80 to 100% on the weight of the fabric of the finishing solution. For polyester-cotton blend fabrics, the wet pick-up Is normally 50 to 80% on the weight of the fabric. 

The number of distinct cycles neecessary to dye the blend fabric was thus reduced from four to two. Using reuse in conjunction with the shortened process, six fabrics were dyed and analyzed. The color differences between the average of all the reflectance measurements and the dyed fabrics ranged from 2.5-5.7 MacAdam units, while those between the first dyed sample and the remaining five fabrics ranged from 3.6-8.5 MacAdam units (Table XXIX), all within or slightly outside the desired lot-to-lot shade tolerances. The color difference with a conventionally-... 

Hauser PJ, Triplett B L and Sujarit C, Plame-resistant cotton blend fabrics , US Patent 4,732,789, 1988, assigned to Burlington Indnstries. 

A range of print table adhesives with superior technical properties which improve control of line and register when printing synthetic or blended fabrics. Available as ready to use solutions or as concentrates. 

Decisive improvement of the appearance and color yield of polyester and polyester/cotton blended fabrics. 

REFORM textile reactant permanently reduces free formaldehyde levels on cured fabric when used with any of the usual durable-press resin systems--glyoxal, carbamate, or urea-formaldehyde. It works with both 100% cotton and cotton/polyester blended fabrics. 

TEXAPRET AM is particularly economical on spun rayons, but it is also used as filling finish for cotton, wool and blended fabrics. 

DANSET MUF is a 64% solids urea formaladehyde condensate in clear liquid form, modified for maximum storage stability. The resin will remain completely water soluble for over a year at room temperature. Its minimum degree of polymerization makes it ideal for shrinkage control and wash and wear properties on rayon and rayon blend fabrics and other cellulosics. 

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