Knitting method

Figure 14.1 Weft knit 3-D fabric made by the Pressure Foot process producing a near net shaped structure, which when collapsed was used for the construction of carbon-carbon aircraft brakes. Source Reprinted with permission from Williams DJ, New knitting methods offer continuous stmctures, Adv Comp Eng Summer, 12-13, 1978. Copyright 1978, Maney Publishing (who administers the copyright on behalf of lOM Communications Ltd, a wholly owned subsidiary of the Institute of Materials, Minerals Mining).

Williams DJ, New knitting methods offer continuous structures, Adv Comp Eng Summer, 12-13, 1978. 

In summary, the Friedel-Crafts alleviation reaction by the FDA knitting method provides a simple and efficient synthetic method to produce... 

By using the simple knitting method, a kind of novel magnetic micro-porous polymer nanoparticle (MMPNs) with high surface area and super-paramagnetic properties has been designed and synthesized successfully (Figure 4.14). ° The BET surface area reached 560 g after hyper-... 

Knit-de-knit method In this method, the yam is knit into a two-inch-diameter hose-leg, heat-set in an autoclave, and then unraveled and wound on to a final package. This texturing... 

Control modules Recent machines are equipped with control computers that manage production parameters and the movement of mechanical parts associated with the needles so that all required movements will be performed for the given knitting method. 

A new process in the circular knitting method with multiaxial laid threads (Fig. 5.23). Completely new fields of application are to be expected for textile-... 

In the calendering method, a PVC compound which contains plasticizers (qv) (60—120 phr), pigments (qv) (0—10 phr), fillers (qv) (20—60 phr), stabilizers (10—30 phr), and other additives, is kneaded with calender roUs at 150—200°C, followed by extmsion between clearance-adjusted roUs for bonding onto the substrate. This method is employed for products with thick PVC layers, ie, of 0.05—0.75 mm thickness. The main plasticizer used is di-2-ethylhexyl phthalate (DOP). For filler to reduce cost, calcium carbonate is mainly used. A woven or knit fabric made of cotton, rayon, nylon, polyester, and their blend fiber is used as substrate. For foamed vinyl-coated fabrics, the bonded materials are heated in an oven to decompose the foam-blowing... 

Air Permeability. Air permeabiUty is an important parameter for certain fabric end uses, eg, parachute fabrics, boat sails, warm clothing, rainwear, and industrial air filters. Air permeabiUty of a fabric is related to its cover, or opacity. Both of these properties are related to the amount of space between yams (or fibers in the case of nonwovens). The most common method for specifying air permeabiUty of a fabric involves measuring the air flow per unit area at a constant pressure differential between the two surfaces of the fabric. This method, suitable for measuring permeabiUty of woven, knitted, and nonwoven fabrics, is described in ASTM D737. Units for air permeabiUty measured by this method are generally abbreviated as CFM, or cubic feet per square foot per minute. 

Inflated Diaphragm Method (ASTM D3886). This method is appHcable both to woven and knitted fabrics. The specimen is abraded by mbbing either unidirectionally or multidirectionally against an abradant having specified surface characteristics. The specimen is supported by an inflated mbber diaphragm under a constant pressure. Evaluation of abrasion resistance can be either by determination of the number of cycles required to wear through the center of the fabric completely or by visual examination of the specimens after a specified number of cycles. 

A second wtinMe-recovery test, AATCC test method no. 128, describes the determination of the appearance of textile fabrics after intentional wrinkling followed by evaluation of appearance in comparison to standard repHcas. A visual rating from 1 (wrinkled) to 5 (smooth) is assigned. This method may be used for both woven and knitted fabrics, whereas the recovery angle method is appHcable only to woven fabrics. 

In the United States tubular knitted fabric is dyed by the pad-batch method for oudets where the edge mark formed as the double thickness tube passes through the padder is accepted. In Europe it is usual to sHt tubular knitted fabric before padding in order to avoid any edge marks. 

In this method the looping yam runs transversely to the length of the fabric. Loops are formed on a row of needles and the next loops are caught in the hooks of the needles and then drawn through the first loops. Weft knitting machines normally give a circular product and can be used to form the... 

PTT POY yams were textured by the false-twist method at 140 to 160 °C. Crimp development was almost twice as high as PET, with crimp contraction reaching about 50 %. When PTT yams with a high level of crimp contraction are knitted into stretch fabrics, the amount of stretch achieved is equivalent to PET stretch fabrics incorporated with 6 to 8 % of Spandex [89], In addition to stretch, PTT fabrics tend to have softer hand and better drape than PET. Since they do not absorb moisture like nylon, PTT fabrics also have a desirable dry touch and comfort. 

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