The flame retardant fabrics and apparels essentially govern a quintessential role in the industries involving hazardous work environments such as welding, electrical, oil and gas industries. This is because in any given disastrous situation, they serve as the last line of defense for the end users. This is precisely the reason that the industry standards regarding the protective fabric have become pretty high over the years. This has also turned the FR fabrics and apparels into-competitive, in-demand commodities which means that there are too many FR fabric suppliers and manufacturers in the market offering a variety of different products of varying quality.
The industry experts always advise the companies to determine the different degrees of danger involved at their profession and outline the requirements attached to the protective wear for their employees. Obviously, this means complete knowledge of the fabric varieties available in the market and understanding of the processes involved in their development. This is important because it will ensure a sound, long-term investment with a reliable provider.
When it comes to the construction of a fabric, many levels of quality input are involved throughout the process till the finished fabric is made including selection of raw materials, yarn making, weaving, bleaching and dyeing. As this article is focused on weaving patterns, we will talk about that. Weaving is one of the most important stages in the production of a flame resistance fabric or any fabric for that matter. This is where the flexibility, strength, take-up, tear resistance and air permeability are added to the fabric. Weaving is the process of two sets of yarns joining together in particular pattern to create a fabric. The first set of yarn is strung tautly across a metal frame and is called warp. The second set, called weft, is connected to metal rods, one thread per rod. This process is carried out on machines called looms. For better understanding of how different fabrics are processed at this stage, let us have a look at common weaving patterns for flame resistant fabrics.
Types of weaving Patterns
Plain weave is the most basic of the weave patterns. In this pattern, warp and weft are overlapped in a simple crisscross arrangement so that each weft crosses over one warp thread and under the next and so on. The next weft thread first goes under the warp threads and then over creating an alternate arrangement to its neighboring set. The plain weave is also the most common and tightest of all weave structures and have two basic variations.
- Balanced Plain Weave – this pattern is made from same weight of threads of both warp and weft as well as same number of ends per inch as picks per inch. This pattern can be identified from its checkerboard-like appearance.
- Basketweave – this variation involves two or more threads bundled together and then woven as one in the warp or weft, or both.
Properties of Plain Weave
- Plain weave is pretty strong and hard wearing.
- A variety of different textures and modifications can be obtained in a plain weave by differentiating the tension level between warps and wefts or the counts of yarn or the varieties of yarn.
- Plain weave fabrics are inexpensive and very adaptive for dyeing, printing and finishing.
Fabrics made from satin weave typically have a shiny surface and dull back. The reason is the unusual arrangement of the weft and warp yarns. In this weave, four or more weft yarns float over a single warp yarn or vice versa. There is less interlacingof threads as either the warp yarn lies on top of the weft in a warp-faced satin or the weft yarn lies on top of the warp yarn in weft-faced satins. This is what gives satin its characteristic sheen on the surface. Here it may be noted that a fabric formed with filament yarns such as silk, nylon or polyester, is called satin. Whereas a fabric made using spun yarns such as cotton is referred to as sateen.
There are three common variations of the satin weave:
- 4-harness satin weave (4HS) – with fill yarns passing over three warp yarns and under one warp yarn
- 5-harness satin weave (5HS) – with fill yarns passing over four warp yarns and under one warp yarn
- 8-harness satin weave (8HS) – with fill yarns passing over seven warp yarns and under one warp yarn
Properties of Satin Weave
- Satin weave gives a fabric high luster, an elegant look and a luxurious feel.
- Satin fabric is one of the most popular and stylish fabrics and has a high durability value.
- Satin fabrics are relatively high maintenance.
Twill weave consists of parallel ribs woven in a diagonal pattern. The way this pattern is achieved is that one or more weft threads pass over one or more warp threads and then taking a sort of “step”, under two or more warp threads, also called creating an offset between rows to create that distinctive diagonal pattern. The twill weave gives the fabric a better draping quality. The twill weave is usually described in a fraction, such as 2/1, which is read as “two up, one down”.
The twill can be classified further in four different ways:
- According to the stepping:
Warp-way: 3/1 warp way twill, etc.
Weft-way: 2/3 weft way twill, etc.
- According to the direction of twill lines on the face of the fabric:
S-Twill or left-hand twill weave: 2/1 S, etc.
Z-Twill or right-hand twill weave: 3/2 Z, etc.
- According to the face yarn (warp or weft):
Warp face twill weave: 4/2 S, etc.
Weft face twill weave: 1/3 Z, etc.
Double face twill weave: 3/3 Z, etc.
- According to the nature of the produced twill line:
Simple twill weave: 1/2 S, 3/1 Z etc.
Expanded twill weave: 4/3 S, 3/2 Z, etc.
Multiple twill weave: 2/3/3/1 S, etc.
Properties of Twill Weave
- The twill weave also has a front and back side called the technical face and technical back, respectively.
- The face side of the fabric is usually more durable and attractive, and used most often as the outer side.
- Twill fabrics are soft and more pliable, and that is why they also drape more freely.
- The yarns can be woven closed together to produce high-count fabrics, which are more durable as well as air and water resistant.
What to look for in an FR Fabric supplier
The rising demand of Flame Retardant Fabrics has attracted a lot of investment in the manufacturing sector and the market is packed with all kinds of suppliers and flame retardant textiles. But when choosing a supplier, a few things should always be given priority.
- FR fabrics are a specialty and technical product and an expertise in them does not come over-night. Therefore, it is always better to choose a well-established, authentic supplier.
- The supplier’s offering should be in accordance with the prevalent industry standards.
- The supplier should preferably have their own fabric production unit. This will ensure a consistency in the quality of the fabric and controlled costs over time.