Nonwovens. Nonwovens: classification and methods of application What materials belong to nonwovens

Nonwovens: classification and methods of application

Nonwoven fabrics are found not only in industrial production, but also in everyday life. These are individual robes and hats, which are given out in the emergency room of any hospital, wet wipes for wiping hands, cleaning cloths, baby diapers and a host of other things that you have to deal with every day. Consider the main types of nonwovens, methods of their production, characteristics and scope.

Nonwovens include materials for the manufacture of which traditional weaving technologies are not used. For the first time such a product made of viscose fibers, bonded with chemicals, was obtained in the middle of the 30s of the twentieth century in France. Currently, in many countries there are large enterprises producing all kinds of nonwovens.

By appointment, they are classified into the following categories:

technical. These are various filtering, wiping, insulating, upholstery and other products used in construction, agriculture and many industries;
household. These include all kinds of materials for sewing clothes, artificial fur, leatherette base, batting, felt, felt, terry cloth, etc.
medical. In any hospital, disposable napkins, towels, diapers and sheets are widely used. In addition, various dressings, tampons, pads and diapers can also be non-woven.

Many catering establishments purchase non-woven tablecloths, aprons, gowns and caps for service personnel. Some companies make uniforms for their employees from such fabrics.

Nonwoven fabric production methods

Natural materials are used as raw materials for the production of nonwoven fabrics: cotton, linen, wool or silk, as well as synthetic and artificial fibers. In addition, textile waste is often recycled.

The manufacturing process includes several stages:

Cleaning and sorting of raw materials. Binding solutions are prepared at the same time.
Shaping the canvas - laying the fibers in different directions.
Linking material.
Fabric processing - drying, dyeing, bleaching, etc.

The classification of technologies for joining fibers into a monolithic product includes several methods.

Glue method

It is most often used for the manufacture of a base for oilcloth, a leather substitute or linoleum, for interlining fabrics - interlining, dublerin, as well as in the printing industry. The decomposed fibers are impregnated with special adhesives, which, when solidified, form a web.

The materials obtained in this way have high strength, rigidity and elasticity. They are resistant to heat, dry cleaning and washing. The characteristic feature is a sufficient level of aeration and significant hygroscopicity.

Knitting and punching method

The prepared and formed fibers are knitted with nylon or cotton threads, forming a rigid frame. Thus, flannel, bike, batting, drape and cloth are obtained.

The materials from which clothes are subsequently sewn have a number of positive qualities. They do not shrink, wrinkle, breathe well and have high wear resistance.

A variation of the method is thread-stitching, in which the fabric is obtained by weaving a system of two or more threads. This is how many fabrics are made for sewing dresses, blouses, men's shirts and even bathing suits. Products made from them keep their shape well and have low thermal conductivity.

Needle punching method

The prepared material is laid out on special machines and subjected to numerous piercing by highly heated serrated needles. As a result, the fibers are randomly entangled, the web is held together.

Most insulation materials are obtained using a needle-punched method - synthetic winterizer, batting and others. Their significant disadvantage is that during operation, individual fibers can penetrate through the top layer. This not only affects the appearance of the product, but also reduces its thermal conductivity and durability.

Thermal method

At the preparatory stage, add a certain amount of fibers having a melting point lower than the bulk. When heated, they quickly melt and form a solid piece.

This technology is used to obtain some types of fillers for upholstered furniture, as well as inexpensive insulation materials for outerwear. They are distinguished by low density, but significant elasticity and resistance to chemicals.

Hydrojet method

Products obtained using this innovative technology are used in medicine, cosmetology: disposable underwear, dressing gowns, dressings, napkins, tampons, sponges, etc. The most famous are sontara, novitex and fibrella.

The method is based on weaving and tying the fibers using high-pressure water jets. Its pioneer is the well-known American company DuPont.

Interesting to know! For the production of baby diapers, the air-forming method is used. The fibers enter the air stream and turn into cotton wool, which is then sprayed onto special adhesive tape.

Felt-felting method

It allows you to get nonwovens from pure wool or mixed raw materials. In conditions of high humidity at a certain temperature, the fibers are subjected to mechanical stress, as a result of which they are felted.

Thus, felt is obtained, which is used for the production of shoes, warm clothes, blankets and other products. In addition, felt is widely used in building construction, since it not only retains heat well, but also provides sound insulation of premises.

The most famous nonwovens

These products have many advantages: softness, elasticity, strength, wear resistance and durability. Modern technologies allow you to create products with pre-programmed characteristics. Let us dwell briefly on the most common materials.

Even 50 years ago, batting was practically the only insulation. It is noteworthy that even hangers for evening dresses and elegant suits were made of it.

Now batting is used only in work clothes - quilted jackets, mittens, comforters, etc. Some manufacturers of orthopedic mattresses also do not forget about this material.

Raw materials for batting are natural or mixed fibers, as well as some wastes from textile and clothing production. They are connected into a canvas using a needle-punched or knitting method. The best quality is considered to be gauze-glued batting. Such a canvas does not deform and has a significant service life.

The disadvantages of batting are considered to be its high weight, the ability to absorb moisture and dry for a long time. In addition, moths can develop in wool fibers. Therefore, modern workwear manufacturers prefer synthetic insulation.

It is a lightweight, bulky and resilient non-woven fabric that has good heat-shielding properties. It is often used not only in sewing jackets and coats, but also in the furniture industry, in the manufacture of pillows, blankets, soft toys, sleeping bags, and shoes.

The synthetic winterizer is obtained by glue or thermal method from synthetic fibers. Its main advantages in comparison with batting are low weight, good dimensional stability and a high degree of heat saving.

It's important to know! The adhesive used in the manufacture of padding polyester can cause allergic reactions. Therefore, it is not recommended to buy clothes or toys with such filler for small children.

Spunbond

Disposable gowns, hats, napkins and sheets made from this fabric are water-repellent. The soft, pleasant-to-touch surface of the spunbond evokes associations with cotton fabrics.

Fibers are produced by forcing molten polypropylene through a plurality of die holes. The frozen threads are formed and thermally joined to form a web. Modern technologies make it possible to obtain spunbond fibers several tens of times thinner than human hair.

Spunlace

Cotton, viscose or polypropylene fibers, which make up the basis of such a fabric, are connected under high pressure by a water jet method. The fabric is characterized by increased strength, air permeability and absence of static electricity.

The material is widely used in hairdressing and cosmetology. The most famous spunlace product is wet wipes.

Thinsulate

In terms of heat-saving properties, this nonwoven material is comparable to swan or eider down. The name "thinsulate" is translated as "subtle warmth". It consists of the finest hollow polyester fibers, each of which is twisted in a spiral. It is thanks to this that the filler keeps its shape perfectly, instantly returning the product to its original appearance after washing.

The thermal characteristics of the material are also noteworthy. In a jacket with thinsulate, a person feels comfortable even in a frost of 40 °. And the amazingly small thickness does not hinder movement and allows you to ski or run freely.

The negative qualities of thinsulate include its ability to accumulate static electricity. But with appropriate treatment, this problem can be eliminated.

Isosoft

Another modern insulation, which was developed by the Belgian concern Libeltex - the largest manufacturer of nonwovens. Isosoft is made up of the finest polyester fibers connected in such a way as to ensure maximum heat saving.

The thickness of the isosoft is 4 times less than that of the padding polyester, and the heating capacity is 10-12 times higher. The material has all quality certificates, so it can be used safely even in children's clothing.

Isosoft easily transfers washing in the machine, without getting lost in lumps and not penetrating the front side of the product. Clothing dries quickly and returns to its original shape. The only disadvantage of the material can be considered only its high cost, but this is more than compensated for by its excellent performance and durability.

From thin and delicate rabbit and goat down, a beautiful material is obtained by felting, which is called. It is used for the manufacture of outerwear, shoes, hats, children's toys and decorative items.

Sometimes, viscose or synthetic threads are added to the fluff to give the product additional strength and resistance to deformation. This felt has a smooth surface with a pleasant sheen.

Felt is actively used to create a variety of crafts. This is facilitated by the fact that the material is well colored, does not crumble during cutting and looks the same both from the front and from the wrong side.

It's important to know! Felt garments may shrink and discolour when washed.... Therefore, to care for them, it is best to use dry cleaning with the use of special products.

Nonwovens, the list of which becomes more extensive every year, are rightly considered the product of tomorrow. The numerous advantages they possess make them indispensable in various spheres of human life.

Nonwovens are produced by bonding a fibrous substance with polyester fibers during heat treatment. Such fabrics are essential for the manufacture of mattresses and other products. The latest technologies are used in production, which fully correspond to the trends of the times. With their help, you can get an excellent result that will fully meet all existing safety and reliability requirements. The fabric of the mattress must necessarily "breathe", as this will allow the product to last as long as possible, and it will always remain fresh. It is very important that the mattress does not absorb sweat inside, because then harmful microorganisms will develop inside that can harm human health.

What are the types of nonwovens?

In total, there are several types of nonwovens that are used for different purposes. Sintepon is a synthetic fabric made of special polyester fiber. It is used as a heater in the manufacture of various clothes and has excellent properties that make it in demand in the market. Sherstepon is a woolen cloth made from natural wool. Its main purpose is also to act as a heater, only in terms of its characteristics it will be slightly better than the previous model and, moreover, it consists of natural components. Cotton-wool is, in turn, a cotton cloth made of cotton fiber. It is also natural and is used for warmer seasons as it does not have outstanding heating properties.

Flaxon, as you might guess, is a linen cloth made of bast fibers (flax, jute, hemp, kenaf). It is used in the manufacture of very light things that fit the body pleasantly and make it possible to feel free in the heat. Vatex is a regenerated fiber web. It is the least common in production, since it does not have outstanding properties and is only needed so that you can somehow usefully dispose of waste.

White wadding is a non-woven canvas made of synthetic polyester fiber. It is used as a heater in down jackets and winter pants. Wool is a canvas made from natural sheep wool. It has an incredible ability to retain heat and is suitable for making things for polar explorers. Batting - non-woven canvas stitched from regenerated fibers.

The history of the development of the nonwovens industry

The 1930s are considered the beginning of the era of nonwovens. The first images were created in Europe. These were canvases of viscose fibers held together by chemical binders. Somewhat later, other methods of their production were mastered, differing both in the type of raw material and in the method of bonding.

The development process of the nonwovens industry in Russia can be divided into four stages:

The first stage is the formation of the industry (60-70s).
The second stage - its heyday - (80s).
The third stage is a sharp decline in production (90s).
The fourth stage is the rise of production and the prospects for the development of nonwovens at the present time.

At the first stage, nonwovens were developed by felting-felt, knitting-stitching and adhesive production methods.

The second stage of the industry's development is characterized by high rates of growth in the production of nonwovens not only for household but also for technical purposes. Since 1975, due to the shortage of cotton fabrics for the needs of the population, science was tasked with replacing technical fabrics with nonwovens.

The third stage in the development of nonwovens is characterized by a sharp decline in production, which lasted from 1992 to 1998. The volume of production of nonwoven fabrics for this period has decreased by almost 15 times.

The fourth stage is characterized by a sharp increase in production. After the collapse of the Russian ruble in 1998, the prices for nonwovens imported from Turkey, Poland, and Germany increased significantly. Therefore, the demand for domestic products increased, as a result of which the volume of output increased almost 4 times. Over the last decade of the development of the nonwovens industry in the Russian Federation, nonwovens "Holofiber" have become the most popular. In 2010, Rospatent recognized this definition as a Well-Known Trademark.

Classification

Nonwovens, depending on the bonding methods, are divided into four classes:

mechanically bonded;
bonded by a physicochemical method;
bonded in a combined way
thermally bonded (thermal bonding).

Raw materials

Nonwovens are produced from both natural (cotton, linen, woolen) and chemical fibers (for example, viscose, polyester, polyamide, polyacrylonitrile, polypropylene), as well as secondary fibrous raw materials (fibers reclaimed from rags and rags) and short fibrous waste from chemical and other industries.

Production technologies

The main technological operations for the production of nonwovens:

Preparation of raw materials (loosening, cleaning from impurities and mixing of fibers, rewinding of yarns and threads, preparation of binders, chemical solutions, etc.).
Formation of a fibrous base.
Bonding the fibrous base(direct receipt of nonwoven fabric).
Nonwoven finish.

Methods for producing nonwoven fabric

The main stage in the production of nonwoven materials is the stage of bonding the fibrous base obtained by one of the methods: mechanical, aerodynamic, hydraulic, electrostatic or fiber-forming.

Bonding methods for nonwovens:

Chemical or adhesive bonding (adhesive method).

The formed web is impregnated, coated or sprayed with a binder, the application of which can be continuous or fragmented. The binder is usually used in the form of aqueous solutions, in some cases organic solvents are used.

Thermal bonding.

This method exploits the thermoplastic properties of some synthetic fibers. Sometimes the fibers that make up the nonwoven fabric are used, but in most cases, a small amount of low melting point fibers (“bicomponet”) is deliberately added to the nonwoven fabric at the spinning stage.

Mechanical (frictional) fastening:

Needle-punching method;

Knitting and stitching method;

Hydro-jet method (Spunlace technology).

Spunlace technology

Spunbond technology

With this technology, the canvas is formed from continuous threads (filaments) obtained from a polymer melt. The filaments are spunblown from the polymer and placed in the web almost simultaneously.

Subsequently, the laid canvas undergoes a mechanical bonding procedure by punching the canvas with needles on both sides, the purpose of which is to seal the laid filaments and entangle them together. At this stage of the technological process, the fabric acquires its strength properties, which can vary depending on the nature, number and pattern of needles stuffing in needle-punched boards. If necessary, the punched canvas is thermally bonded using a calender.

This technology is becoming very popular, since the product obtained by this method of production has unique properties, practicality and low cost.

Spunjet technology

A technology in which the final fixation takes place using high pressure water jets. The strength of the finished material is incomparably higher than that of a nonwoven fabric bonded by any other means.

Strutto technology

The technology came to Russia from Italy. "Strutto" refers to the vertical stacking of fibers in the production of nonwovens. For the first time the technology was applied in Russia by the company "Factory of Nonwoven Materials" Ves Mir "for the production of nonwoven filler for upholstered furniture StruttoFiber® (" Nonwoven independent springs ").

AirLay technology

AirLay technology is a filament formation system ready for needling and curing. This technology is intended as a replacement for outdated cards and liners. The productivity of such a line allows the production of about 1500 kg of finished products per hour. The grammage of the produced material varies from 150 g / m² to 3500 g / m². The use of AirLay technology is varied. For example, the automotive industry, agriculture, upholstered furniture (Bi-Cocos material), construction, clothing and packaging.

Application

Spunlace, are used for household needs; for hygienic use - wipes; for medical needs, in particular for surgery, - disposable medical clothing, as well as for technical applications in accordance with the strict requirements of the client.
Materials made by technology Spunbond, are used in road and railway construction as a load-distributing foundation, in the construction of sludge dumps - as a drainage layer, in industrial and civil construction - as heat and vapor insulation.

Trade names

Spunlace:

Sontara (DuPont, USA, Mogilevkhimvolokno), composition: cellulose 50%, polyester 50%,

Spunlace, Novitex (Novita, Poland), composition: viscose 70%, polyester 30%,

Fibrella (Suominen, Finland), composition: viscose 80%, polyester 20%.

Nonwovens obtained by technology Spunbond:

Canvalan (SIBUR, Orton, Russia, Kemerovo), composition: 100% polypropylene,

Geotex (SIBUR, Sibur-Geotextile, Russia, Surgut,), composition: 100% polypropylene.

Nonwovens obtained by technology "Strut":

Bulky nonwoven fabric "Sprut" (Ukraine).

StruttoFiber® (Moscow region), composition: 100% polyester.

HolloTek® ("Ves Mir", Podolsk), composition: 100% polyester.

Nonwovens obtained by technology thermal bonding:

Fibertex (Tornet-LTV, Russia, Drezna), composition: 100% polyester,

Sherstipon (Tornet-LTV, Russia, Drezna), composition: wool 70%, polyester 30%,

Holofiber (Termopol-Moscow, Russia, Moscow), composition: polyester 100%,

Vlad-ek (Vladpoliteks, Russia, Sudogda), composition: 100% polyester

Nonwovens obtained by technology needle-punched fastening:

ECO-TOR (Tornet-LTV, Russia, Drezna), composition: 100% polypropylene,

Literature

Notes (edit)

Links

Wikimedia Foundation. 2010.

Textile materials consisting of fibrous webs or threads held together in various ways are called nonwovens.

There is no spinning and weaving in the technological process of obtaining nonwoven textile materials. Only some nonwovens are made from yarns, but without the weaving process.

The range of nonwovens is expanding as they are much cheaper than fabrics. Nonwovens are used for the production of sewing and haberdashery products, furniture, cars, footwear.

Nonwovens are produced mainly in three ways:

Mechanical (felted-felt, needle-punched production methods);

Physicochemical (adhesive sheets);

Combined (knitting and stitching and glue, needle-punched and glue, etc.).

The raw materials for the production of nonwovens are cotton, wool, waste of natural fibers of textile production, artificial and synthetic threads.

By appointment, nonwovens are divided into household, wiping, packaging, investment, shoe.

Nonwovens (non-adhesive) have good hygroscopicity, air permeability and heat-shielding properties. They are resistant to deformation, soft to the touch, cheaper than fabrics. The disadvantages of nonwovens are their low strength and abrasion resistance.

Non-woven materials are called a special type of fabrics made without the use of flat weave technology. There are many types of such products to date, as well as the methods for their manufacture. The wide and scope of application of the material of this variety. Most often, nonwoven fabric is used in construction and agriculture, as well as in sewing clothes.

A bit of history

For the first time nonwoven fabric was made in the second half of the 19th century in the USA. The first canvases of this variety were made from starch bonded to each other. This material, called a pellon, did not receive much distribution in the 19th century. It began to be used quite widely only during the Second World War. The Americans used it to make camouflage products.

In the 70s of the last century, pellon was first used in agriculture as a covering material. At the moment, it is precisely it that is used on 30% of the agricultural areas of the EU countries. In the USSR, such material was produced in very small quantities and was used mainly in the widespread in our country, it received only in the 90s. Now it is produced by many Russian companies. For example, a very high-quality product of this type is produced by the Podolsk nonwoven fabric factory "Ves Mir", founded in 2000.

Density

Nonwoven fabric can be made in different ways, have different thickness, appearance and purpose. However, the main characteristic of such sheets in most cases is strength. The latter, in turn, depends on the surface. This parameter in groups of different purpose can vary within the range of 10-600 g / m 2. So, for example:

The nonwoven fabric is typically 235 to 490 g / m 2.

For needle-punched fabrics, this figure is 210 g / m 2.

The density of fabric-stitched materials is 216-545 g / m 2.

Non-woven fabric has a surface density of 90-110 g / m 2.

For thread-stitched fabrics, this figure is 63-310 g / m 2.

The density of the glued nonwoven fabric is 40-330 g / m 2.

Canvases of this type can be produced mechanically or by glue. The basis of any such material is a canvas made of natural and synthetic fibers, laid in rows. To obtain a fibrous structure, such a web is combed.

Mechanical production methods

Bonding the base of the nonwoven fabric using this technology is performed using additional threads. For example, stitching materials are made mechanically. In this case, the fibers of the base are fastened together by stitching them with threads. When using needle-punching technology, the elements forming the canvas are pre-mixed with each other. The result is a fairly dense fabric in structure. To give it greater strength, it is stitched with thick threads. In this case, they use special tools with notches. The needle-punched method of making canvases is currently the most popular. This technology is used by every nonwoven fabric factory.

Thread-stitching materials are made by passing the warp with one or more fiber systems. Such a canvas differs from a canvas-stitched one, first of all, in its appearance. The material of this group is similar to terry cloth.

There are also mechanically stitched fabrics on sale today. This variety is produced on a very light basis also by stitching it with a pile thread system. Such canvases can be either smooth or terry.

Adhesive production of nonwovens

This technology is used in the manufacture of most types of nonwovens. In this case, the fibers are bonded in the canvas by impregnating them with various kinds of adhesives. Most often, synthetic latex is used for processing. Another common technology is hot pressing. In this case, the fibers are bonded with thermoplastics at a very high temperature.

Sometimes the oldest technology is also used for the production of nonwoven glued materials - on paper machines. It was with the use of such equipment that Pellon was produced in America. In this case, the binder can be introduced either directly into the mass entering the machine, or already into the finished web.

Use of stitched canvas

Such non-woven material is distinguished by its great thickness, massiveness and looseness. Its main advantage is its high heat-shielding properties. Stitched fabrics are very dense and wear-resistant materials that can give significant shrinkage. They are used most often as lining in the manufacture of clothing. They are also sometimes used as a base in the manufacture of artificial leather.

Where is needle punched material used?

Due to the porous structure, this group of canvases also has good heat-shielding properties. In addition, the advantages of such a material include resistance to washing and dry cleaning. Needle-punched fabrics are usually used for floor coverings. Like canvas stitched ones, they are also used for the manufacture of linings for coats, jackets and fur coats. However, in the latter case, the needle-punched nonwoven material usually has to be additionally impregnated with adhesives. The fact is that its fibers are quite tough, and therefore, in a free state, they are able to penetrate through the upper one and spoil its appearance.

It is the needle-punched method that is also made the most common non-woven material - dornit. Geotextiles are used when laying out lawns, erecting foundations, etc. Also, the needle-punched method is sometimes used in the production of the most popular type and greenhouses - spunbond. However, more often this type of fabric is still made by the glue method (hot pressing).

Application of thread and fabric-stitched fabrics

Both of these varieties are also quite in demand in the industry. The main advantage of thread-stitched fabrics is the variety in appearance. This method can be used to produce both very thin translucent materials and massive furniture materials. Suits, evening dresses, casual wear, scarves, napkins from non-woven material are often made using this technology.

The advantages of fabric-stitched materials are their stable structure and hygiene. In terms of wear resistance, they surpass all other types of nonwovens. This fabric is used mainly for sewing dressing gowns and beach suits.

Where are adhesive sheets used?

Most often, such a non-woven material is made from a mixture of cotton and nylon fibers. It is usually used when sewing clothes. For example, it is inserted into collars, tabs and slots to give the latter rigidity. Materials made on paper machines are most often used for the production of all kinds of medical dressings.

As you can see, the field of application of nonwoven fabrics in our time is really very wide. Their excellent performance characteristics make them indispensable for sewing many types of clothing, growing plants, installing drainage systems, etc. The technologies for the production of such materials are not particularly complex, and therefore their cost is usually low. Basically, this is what explains the extraordinary popularity of this type of canvases.