Multi-Layer Fabrics: the art of weaving several layers in a fabric

A multilayer fabric with woven layers consists of a number of woven layers stacked on top of each other and held together with connection yarns in the third dimension (Z-direction). This article Knitting fair introduces to you.

Technical textiles are the fastest growing sector in the textile industry. Therefore, it is highly essential to develop all techniques and types of equipment in order to decrease the production time especially with the use of electronically equipped modern looms and communicated with computers.

The automatization of woven design is one of the ways to facilitate the work and to increase the production, especially in the conventional weaving of complex structure, due to the time consuming and difficulties involved in the manual design (e.g., the combination of weaves, seeking of stitches and introducing it, generating of lifting plan, doing cross-sections, etc. However, a number of CAD/CAM fabric woven structures with complicated weaves have been developed and represented in the form of 2D and 3D matrices.

Some of these researches depended on mathematical functions to describe and generate automatically the 2D and 3D weaves. In other words, the algorithm of the Kronecker Product was applied to describe weaves. In addition, other CAD/CAM software’s that deal with geometric modeling of woven structures have been developed to visualize the fabric appearance before weaving (Liao & Adanur, 1998; Lomov, Perie, Ivanov, Verpoest, & Marsal, 2011; Smith & Chen, 2009). However, they do not discuss all the problems due to the wide variety of weaves and stitching ways.

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Definition Multilayer fabrics

A multilayer fabric consists of several layers woven above each other with a maximum of 12 woven layers or 22 warp yarn layers and 23 weft yarn layers (unidirectional layers). The connection can be realized by connection yarns in the third dimension or by interlocking. As a result, the delamination resistance of the fabric increases and the manual labor of stacking different layers on top of each other could be decreased. All types of yarns can be used and combined. This combination could be different layers with different types of yarns but also in one-layer different types of yarns can be used.

3D Weaving

The term 3D weaving is commonly used in reference to the weaving of cloths that have pre-designed three-dimensional shapes (multilayer fabrics) or can be directly manipulated by interlocking and non-interlocking methods into a 3D shape immediately after being woven. It is also used to describe the weaving of fabrics with substantial thicknesses, many times greater than the diameters of the yarns used to produce the fabrics.

3D Shape Weaving

Conventional projectile/rapier-dobby/ Jacquard looms can be used to produce certain three-dimensional shapes by weaving multiple layers of fabric interlinked to each other, similar to a ‘double cloth, treble cloth ‘formation, so that after being woven the layers of 2D fabric can be manipulated into the required 3D shape; for example, a dobby/jacquard loom can be used to produce the cellular structures. For obvious reasons, this method is also termed multilayer weaving.

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It is highly essential to have knowledge and understanding of double/treble cloths which are basic for the formation of multilayer fabric

Double cloths structures—The simplest structure of double cloth is composed of two series of warp threads and two series of weft threads. One series of each kind forming an upper or face fabric, and the other, an under or back fabric. It is necessary for the face picks, to be arranged in definite order with the backing picks, and the face ends with the back ends

Treble cloths structure—In treble cloths there are three series of warp and weft threads which form three distinct fabrics one above the other. Except for the forties, when a face pick is inserted all the center and back ends are left down; when a center pick is inserted all the face ends are raised, and all the backing ends are left down, while a backing pick is inserted all the face and central ends are raised.

For more knitwear knowledge, please pay attention to the knitting fair.

Source: textiles school

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In today’s garment business environment of global competition, reduction of the total cost of quality strengthens one’s competitive position by focusing on the drivers of different key components of nonconformance.

Cost of Quality in the garment industry is still a widely understood misconception. The term often gets associated incorrectly with the price of creating quality merchandise. Actually, it is the other way round i.e. the amount of money incurred because the product was not manufactured right at the first time.

Thus, the concept of quality costs in the garment industry is a means to quantify the total cost involved in quality-related efforts and deficiencies pertains to a manufactured garment product.

Most of the garment units do not know what their quality costs. A large portion of resources is consumed in finding and correcting mistakes in the merchandise or related processes. Typically, the cost to eliminate failure in the customer phase is five times greater than it is at the merchandise development or manufacturing phase. Every time work is redone, the cost of quality increases. The obvious examples in the garment sector include:

The reworking of a garment

The retesting of performance of apparel

The rebuilding of a garment machine

The correction of a garment size specification sheet or change of care label

The reprocessing of the garment to improve dimensional stability after a wash or the replacement of trim to fulfill the requirement of a customer or to meet safety issues.

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The cost of poor quality affects internal and external costs resulting from failure to meet the requirements specified for an apparel product by the garment industry.

On the other hand, the cost of good quality affects the cost of investing in the prevention of nonconformance to requirements and the costs for appraising the garment product for conformance to requirements. Thus, the cost of quality concept leads to the following classification for a better understanding of the situation in the garment sector.

How to classify Quality Cost in Garment Industry?

However, no standard relationship exists among the four parameters of quality costs. One can expect to reduce the internal and external failure costs by increasing prevention and appraisal costs. But it is also well understood that, in spite of the excellent quality of raw materials and good inspection coverage, the quality of a garment also depends on workmanship, which may be a prime factor of hindrance in the attainment of quality owing to poor training, poor maintenance of machines, and lack of requisite skill.

What is Prevention Cost?

Prevention Costs:

The costs of all activities specifically designed to prevent poor quality in a garment product or associated processes.

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Internal Failure Costs:

Failure costs that arise before a garment company supplies its product to the customer i.e. prior to delivery or shipment of the merchandise. These are due to deficiencies discovered before delivery and are associated with the failure (non-conformance) to meet the needs of customers. If internal quality failures of defective merchandise are identified before shipping then optimistically there may be no external failure costs.

xternal Failure Costs:

These are typically due to errors found by customers. Failure costs that arise after a garment unit supply the product to the customer, such as cost of returned merchandise, cost of quality claims, cost of transportation for the defective merchandise, personnel costs associated with these activities. These costs can be much higher than internal failure costs because the stakes are much higher.

owever, many of the costs of quality are hidden in the garment sector and difficult to identify by formal measurement systems.

A typical iceberg model can be used to illustrate this matter. Only a minority of the costs of quality appears above the surface of the water. But there is a huge potential for reducing costs under the water. Identifying and improving these costs may significantly reduce the costs of doing the garment business.

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Concluding Remarks

A proper understanding of the cost of quality is vital for any organization to develop quality conformance as a useful strategic business tool that improves its product performance and the brand image. This is important in achieving the objectives of a successful organization and guides to identify improvement opportunities.

Undoubtedly, the reduction of cost of non-conformance in different unit operations is much more preferable in this sector to increase the volume of sales turnover, especially in a competitive market or in an environment of recession.For more knitwear knowledge, please pay attention to the knitting fair.

Source: textiles school

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There are many elements in addition to colors and patterns that you need to consider to buy the best fabric. This article Knitting fair introduces to you.

When buying fabrics, you want the very best but sometimes the choices are many and it can feel a little confusing when you are in a textile showroom. The first thing that will, of course, attract you will be the color and patterns of the fabrics on display. However, that is only one element of the fabric by the yard, there are many other elements that you need to consider for you to buy the best fabric. Some of the things you must look out for when buying fabrics are as follows:

Quality of the fabric

Before you even check whether it’s linen, cotton, polyester or nylon, you must feel it against your skin and feel whether it is of good quality. The fabric must be blemish-free especially when it comes to things such as dye, print, fibers, tears and so on. The quality should be perfect because if the fabric has blemishes, you will no doubt have clothes made that will depict those imperfections in the fabric.

Type of Fabric

Fabrics are mainly categorized as natural, synthetic or a blend of both. Good examples of natural fabrics are Cotton, Linen, denim, leather, silk. Synthetic fabrics are such as Polyester, rayon, spandex, DTY fabric, Acrylic, Nylon and so on. Fabrics with a blend of natural and synthetic fibers are also perfect for making clothes as long as they are in perfect condition. So, ask yourself whether you want to buy natural, synthetic or fabrics that are a blend of both. Natural fabrics tend to cost more compared to synthetic ones so your budget here will also have a role to play.

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Color Fastness

As you check your fabric out, make sure that the color is even minus any spots or streaks. Closely scrutinize the fabric and note any signs of uneven dyeing. If you happen to notice any areas with colors fading especially on the fold line you should move on to another fabric. When you see light colors in some parts of the fabric, unless it is a design of the fabric, don’t buy it because that is a sign that the color will fade when you wash the fabric. If you have to test it then use a white handkerchief or cotton ball which you have dampened and then rub it on a small part on the fabric, if the color appears on the kerchief or cotton then the fabric is not of good quality.

Suitability and Location

You probably have some sort of garment in mind when buying the fabric and you have to know the suitability of the fabric then. For example, you cannot make wool swimsuit or cotton sports clothes or polyester baby clothes. Think of the occasion and the place where the garments will be worn as you choose the fabrics to make them. Wool will not do in a desert environment and chiffon will definitely not be right for visiting the cold alpine region. The cotton fabric would be perfect for summer clothes since they are perfect for cooling the skin.

Shrinkage

You have to consider the shrinkage factor when choosing your fabric. You have to know if the fabric will shrink after getting washed. Every fabric shrinks differently. In order to be on the safe side, by an extra 10% of the fabric. If you can consider a preshrunk fabric which will not give you trouble. Preshrunk fabrics have labels such as “Sanforised”, “Mercerised” and so on.

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Color

The color of the fabric is very important especially if you are choosing the fabric to make your own dress. Choose a color that agrees with your skin tone to make the dress even more beautiful on you. If it’s a wedding color and you are buying fabric to make several dresses, just ensure that the color is in accordance with the `wedding theme color. Shop for the fabric in broad daylight and not after sunset if you are going to an actual brick and mortar shop. Artificial lighting can in some cases distort the color which is why you need natural light to tell the real color.

Just remember that once the fabric has been cut from the bolt, you cannot return it when you realize it’s the wrong color after buying it. It will not be accepted, and you will be forced to spend more on the right color of material this time around. This could really put a dent in your budget.

Pattern

You might be considering buying patterned fabric after you see the various appealing patterns on display. Just take into great consideration the fact that there will be pattern repeat in these fabrics which should influence the cutting. The motifs on the fabric have to be distributed in a systematic manner by being placed correctly especially at the seams. Be careful and ensure that the fabric doesn’t become distorted or when matched up or lined to create the garment. When it comes to patterns, choose one that will best represent the fashion look you intend to achieve with the dress created in the end.

The Fabric Grain

This should be a major consideration when buying fabrics because as much as you buy the most attractive fabric, it might present some challenges if the grain isn’t right. With the wrong grain on the fabric, the outfit you make with it will hang wrong. The moment you realize the grain of the fabric is all wrong don’t buy it to avoid further complications down the road.

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Fabric weight

The fabric weight is in most cases determined by factors such as the fiber type, weave and so on. The weight of the fabric can be indicated by GSM which can vary from 60-700. A denim fabric, for example, will have a GSM of 400 of course depending on the weave. Just remember that a higher fabric weight does not necessarily mean that the fabric is of fine quality. The fabric weight should mainly influence suitability. Knowing the fabric weight will help you compare various types of fabrics and decide on the best fabric for garments of certain occasions and environments.

Buying fabrics shouldn’t be a headache now that you know what to look for, thanks to the above list. Go out there and shop for the fabric of your dreams and transform it into the most fashionable designs of garments.

For more knitwear knowledge, please pay attention to the knitting fair.

Source: textiles school

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