In order to assist individuals who are trying to determine if a knitted material is what they need, LAMB is pleased to set forth below some basic information on narrow fabric knitted structures and the machines used to produce them. Please note that additional information will be posted in this section each year.
Basics of Narrow Fabric Knitting
Why Knitting?
There are three principal methods of manipulating fibers or yarns into textile fabrics:
Interweaving - 2 sets of straight threads intersecting at right angles (weaving).
Intertwining - threads are caused to intertwine with each other at any set angle (braiding & twisting).
Interlooping - forming yarn(s) into loops and intermeshing the loops into a structure (knitting).
I.) In General
Knitting is the simplest and most productive method of forming narrow fabrics.
Knitting is faster than braiding but slower than weaving or twisting
Knitting does NOT require the use of special yarn packages as do weaving, braiding and twisting.
This eliminates the requirement that the yarn be respooled onto special packages. This reduces the total production time of the material.
II.) PROPERTIES
A. Stretch - Elongation
Because of their inherent intermeshed loop structure, knits are highly elastic especially along the vertical axis. The elasticity of the loops allows knits to be softer and thus more comfortable, an important consideration when using them in apparel products. In applications where stretch must be controlled or reduced, there are several techniques available to reduce the elongation of a knitted material.
B. Resiliency
Knit materials are more resilient than other textile structures in that they can be bent or curved around a surface without being distorted. This property makes knitted materials ideal for use in gasketing products.
C. Porosity
Knit materials are also more porous than other textile structures. Although a material knit at a high “stitch density” can appear to be opaque, it would be possible for a gas or liquid to penetrate it. This same characteristic, however, makes knits ideal in applications where filtration and absorption properties are required.
D. Stability
Depending on the type of knit structure, some knit materials can be unraveled from the ends. However, when cut along the vertical axis, a knit is more stable than a woven or braided material.
E. Type of fibers that can be knit
An old rule in knitting was that knitting required a relatively fine, smooth, strong yarn with good elastic recovery properties. Today, that rule no longer applies as all types of fibers and materials have been knit into textile structures including fiberglass, Kevlar and Wire as thick as .015-inch in diameter. On some machines, wire can be knit at the rate of 4 to 6 feet per minute.
