Fancy Yarns :
Marl yarn
The simplest of fancy yarns are marl yarns and yarns made by twisting two different colored yarns together in a double process. It has a different structure from normal double yarn. The yarn structure shown in Figure 1 clearly shows the color variation of the two yarns, showing the dominant effect of the marl yarn, as well as the flat structure of the simple folded yarn. These yarns are used to create discreet pinstripes in men's suiting or to create a finely and irregularly patterned woven fabric with relatively simple fabric construction. They can also be used to provide a Lurex or other metallic yarn with a strong backing, while at the same time creating a more subtle effect.
Spiral or corkscrew yarn
A spiral or corkscrew yarn is a plied yarn that exhibits a characteristic smooth spiral of one yarn element around another and is similar in structure to a marl yarn. Figure 1 shows the basic structure, which is straightforward except for the different lengths of the two yarns used.
Gimp yarn
A gimp yarn is a composite yarn consisting of a twisted core wrapped around an impact yarn to create a wavy projection on the surface of the yarn. This structure is shown in Figure 1. Due to the requirement of the binder yarn to give stability to the structure, the yarn must be made in two stages. Two yarns of widely varying numbers are pleated together, thickened around, and then reverse bound. The reverse binding process eliminates the twist that creates wavy profiles because it makes the effect yarn longer than the actual length of the finished yarn. The texture properties of a gimp are obviously better than those of a spiral yarn. The finer of the two gimps shows that the effect is less regular and perhaps less defined.
Diamond thread
A diamond yarn is produced by folding a coarse single yarn or twisting it with a finer yarn or filament of opposite color using an S-twist. It is wired with a similar fine yarn using jade twist. Multiple 'cabled' yarns can be created by expanding and modifying this technique to create a wide range of effects. A real diamond yarn shows some shrinkage effect from thinner to thicker yarns, but this is not shown in Figure 1 for the sake of clarity. Diamond yarn is very useful for designers to create subtle effects of color and texture. Especially in relatively simple fabric structures.
Boucle yarn
This type of yarn is characterized by tight loops projecting from the yarn body at fairly regular intervals, as shown in Figure 1. Some of these yarns are made by air-jet texturing but most are of three-ply construction. The three components of the yarn are the core, the effect and the tie, or binder yarn. Effect yarn is wrapped in loops around a core or base yarn and then a third ply or binder is wrapped over the effect ply to hold the loops in place. Individual plies may be filaments or spun yarns. These material yarn properties determine the final design effect.
Fig 1 : Different Type of Fancy Yarns |
Loop yarn
A loop yarn has a core around which an impact yarn is wrapped and is overfed to form a nearly circular loopy projection on its surface. Figure 2 shows the structure of a loop yarn, in this case simplified somewhat by showing the core as two straight bars. In fact, the core is always two yarns twisted together, which traps the impact yarn. As a general rule, four threads are involved in construction. Two of these form the main or ground yarn. Effect yarn(s) are formed with an overfeed of about 200% or more. It is important for these to be of the right type and of good quality. Even, low-twist, elastic and flexible yarns are required. Impact yarn is not completely bound by the ground thread and therefore requires a binder. The size of the loops is determined by the level of overfeed, the location of the grooves in the drafting rollers, the spinning tension or the level of twist of the impact yarn. Loop yarn can also be made with slivers in place of yarn for effect.
Snarl yarn
Snarl yarn has a similar twisted core-to-loop structure. Again for simplicity, the core is shown as two parallel bars in Figure 2. A snarl yarn exhibits 'snarls' or 'twists' projecting from the core. It is produced by a method similar to loop yarn, but uses a vibrant, high-twist yarn as the impact yarn and a slightly higher excess feed. The required size and frequency of snarls can be obtained by careful control of additional feed and details of spinning tension and the level of twist of the impact yarn.
Fig 2 : Loop yarn and Snarl yarn |
Nap/Knop yarn
Slab yarn
Fascinating yarn
Fig 3 : Knop, slub and fasciated yarns |
Tape yarn
Chainet yarn
Chenille yarn
FIg 4 : Tape yarn, chainette yarn and chenille yarn |
Ribbon yarn
Composite yarn
Covered yarn
Metallic yarn
Fig 5 : Covered yarn and metallic yarn |
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