Development history of the nonwovens industry
The beginning of the era of nonwovens is considered to be the 1930s. The first images were created in Europe. These were canvases made of viscose fibers fastened together with 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 process of development 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 in production and the prospects for the development of nonwovens at the present time.
At the first stage, non-woven materials were developed by felting, knitting and stitching and adhesive production methods.
The second stage of the development of the industry is characterized by high growth rates in the production of non-woven materials, 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 has been tasked with replacing technical fabrics with non-woven materials.
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 non-woven fabrics for this period 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, non-woven materials imported from Turkey, Poland, and Germany became very expensive. Therefore, the demand for domestic products increased, as a result of which the output increased almost 4 times. Over the past decade of the development of the nonwovens industry in the Russian Federation, Hollofiber nonwovens have become the most popular. In 2010, Rospatent recognized this definition as a well-known trademark.
Classification
Non-woven materials, depending on the bonding methods, are divided into four classes:
- fastened mechanically;
- bonded by physical and chemical means;
- bonded together
- thermally bonded (thermal bonding).
Feedstock
Non-woven materials are produced from both natural (cotton, linen, wool) and chemical fibers (for example, viscose, polyester, polyamide, polyacrylonitrile, polypropylene), as well as secondary fibrous raw materials (fibers regenerated from rags and rags) and short- fibrous waste from chemical and other industries.
Receiving technologies
The main technological operations for obtaining nonwoven materials:
- Preparation of raw materials (loosening, cleaning from impurities and mixing fibers, rewinding yarn and threads, preparing binders, chemical solutions, etc.).
- Formation of the fibrous base.
- Bonding the fibrous base(directly obtaining non-woven material).
- Non-woven fabric 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.
Methods for bonding nonwoven materials:
- Chemical or adhesive bonding (adhesive method).
The formed web is impregnated, coated or sprinkled with a binder, the application of which may 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 certain synthetic fibers. Sometimes the fibers that make up the nonwoven material are used, but in most cases, a small amount of fibers with a low melting temperature (“bicomponent”) is deliberately added to the nonwoven material at the spinning stage.
- Mechanical (friction) fastening:
Needle-punched method;
Knitting-stitching method;
Hydrojet 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 formed from the polymer by means of a spin-blown method and are laid almost simultaneously in the canvas.
Subsequently, the laid canvas undergoes a mechanical bonding procedure by punching the fabric with needles from both sides, the purpose of which is to compact the laid filaments and tangle them together. At this stage of the technological process, the fabric acquires its strength properties, which may vary depending on the nature, quantity and pattern of needle 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.
Spandget 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 non-woven fabric bonded by any other means.
Strutto Technology
The technology came to Russia from Italy. "Strutto" refers to the vertical laying of fibers in the production of nonwovens. For the first time the technology was applied in Russia by the company "Factory of Non-woven Materials "Ves Mir" for the production of non-woven filler for upholstered furniture StruttoFiber® ("Non-woven independent springs").
AirLay Technology
AirLay technology is a system for producing fibers ready for needle punching and heat setting. This technology is intended as a replacement for obsolete cards and lappers. The capacity of such a line allows to produce about 1500 kg of finished products per hour. The weight of the produced material varies from 150 g/m² to 3500 g/m². The use of AirLay technology is diverse. For example, the automotive industry, agriculture, upholstered furniture (B-Coconut material), construction, clothing and packaging.
Application
- Spunlace, are used for household needs; for hygienic use - wiping wipes; for medical needs, in particular surgical ones - disposable medical clothes, 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 base, in the construction of sludge dumps - as a drainage layer, in industrial and civil construction - as a heat and vapor barrier.
Trade names
- Spunlace:
Sontara (DuPont, USA, Mogilevkhimvolokno), composition: cellulose 50%, polyester 50%,
Spunlace, Noviteks (Novita, Poland), composition: viscose 70%, polyester 30%,
Fibrella (Suominen, Finland), composition: viscose 80%, polyester 20%.
- Nonwovens produced by technology Spunbond:
Kanvalan (SIBUR, Orton, Russia, Kemerovo), composition: polypropylene 100%,
Geotex (SIBUR, Sibur-Geotextile, Russia, Surgut,), composition: 100% polypropylene.
- Nonwovens produced by technology "Strutto":
Volumetric non-woven material "Octopus" (Ukraine).
StruttoFiber® (Moscow region), composition: 100% polyester.
HolloTech® ("Ves Mir", Podolsk), composition: 100% polyester.
- Nonwovens produced by technology thermal bonding:
Fibertex (Tornet-LTV, Russia, Drezna), composition: polyester 100%,
Sherstipon (Tornet-LTV, Russia, Drezna), composition: wool 70%, polyester 30%,
Hollofiber (Termopol-Moscow, Russia, Moscow), composition: polyester 100%,
Vlad-ek (Vladpolitex, Russia, Sudogda), composition: polyester 100%
- Nonwovens produced by technology needle-punched bonding:
ECO-TOR (Tornet-LTV, Russia, Drezna), composition: 100% polypropylene,
Literature
Notes
Links
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Nonwovens: classification and methods of application
Non-woven fabrics are found not only in industrial production, but also in everyday life. These are individual gowns and caps that 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 daily. Consider the main types of nonwoven materials, methods of their production, characteristics and scope.
Non-woven materials 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 mid-30s of the twentieth century in France. At present, in many countries there are large enterprises that produce all kinds of nonwoven materials.
According to their purpose, they are classified into the following categories:
- technical. These are various filtering, cleaning, insulating, upholstery and other products used in construction, agriculture and many industries;
- household. These include all kinds of materials for tailoring, artificial fur, the basis of leather substitutes, 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, bathrobes and caps for service personnel. Some companies sew uniforms for their employees from such canvases.
Methods for the production of nonwovens
As raw materials for the production of non-woven fabrics, natural ones are used: 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. At the same time binder solutions are prepared.
- Forming the canvas - laying the fibers in different directions.
- Binding material.
- Fabric processing - drying, dyeing, bleaching, etc.
The classification of technologies for connecting fibers into a monolithic product includes several methods.
glue method
It is most often used for making bases for oilcloth, 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. A characteristic feature is a sufficient level of aeration and significant hygroscopicity.
Knitting and punching method
Prepared and shaped fibers are knitted with nylon or cotton threads, forming a rigid frame. In this way, flannel, baize, batting, drape and cloth are obtained.
The materials from which clothes are subsequently sewn have a number of positive qualities. They do not shrink, do not wrinkle, pass air well and have high wear resistance.
A variant of the method is thread stitching, in which the fabric is obtained by interlacing a system of two or more threads. This is how many fabrics are made for sewing dresses, blouses, men's shirts and even swimwear. Products from them keep their shape well and have low thermal conductivity.
Needle-punched method
The prepared material is laid out on special machines and subjected to numerous piercings with highly heated jagged needles. As a result, the fibers are chaotically entangled, the fabric is fastened together.
In the needle-punched way, most heaters are obtained - synthetic winterizer, batting and others. Their significant disadvantage is that during operation, individual fibers can penetrate 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 product. 
This technology is used to obtain some types of fillers for upholstered furniture, as well as inexpensive insulating 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, gowns, dressings, napkins, tampons, sponges, etc. The most famous are sontara, novitex and fibrella.
The method is based on weaving and binding fibers with high-pressure water jets. Its pioneer is the well-known American company DuPont.
Interesting to know! For the production of baby diapers, the airforming method is used. The fibers enter the air stream and turn into cotton wool, which is then sprayed onto a special adhesive tape.
Felt felting method
It allows you to get non-woven materials from pure wool or blended 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.
In this way, felt is obtained, which is used for the production of shoes, warm clothes, blankets and other products. In addition, felt is widely used in the construction of buildings, since it not only retains heat well, but also provides sound insulation for rooms.
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 coat hangers for evening dresses and elegant suits were made from it.
Now batting is used only in work clothes - padded jackets, mittens, balaclavas, etc. Some manufacturers of orthopedic mattresses also do not forget about this material.
The raw materials for batting are natural or mixed fibers, as well as some waste from textile and clothing production. They are connected into a fabric by a needle-punched or knitting method. The highest quality is considered batting with gauze sizing. Such a canvas is not deformed and has a significant service life.
The disadvantages of batting are its large weight, the ability to absorb moisture and dry for a long time. In addition, moths can start in wool fibers. Therefore, modern manufacturers of workwear prefer synthetic insulation.
This is a light, voluminous and elastic non-woven fabric that has good heat-shielding properties. It is often used not only for sewing jackets and coats, but also in the furniture industry, in the manufacture of pillows, blankets, soft toys, sleeping bags, shoes. 
The synthetic winterizer is obtained by gluing or thermally from synthetic fibers. Its main advantages compared to batting are light weight, good dimensional stability and a high degree of heat saving.
It's important to know! The adhesive composition used in the production of padding polyester can cause allergic reactions. Therefore, it is not recommended to buy clothes or toys with such a filler for small children.
Spunbond
Disposable gowns, caps, napkins and sheets made from this material are water-repellent. The soft, pleasant to the touch surface of spunbond is associated with cotton fabrics.
Fibers are obtained by forcing molten polypropylene through a plurality of spinnerets. The cured threads are spun and thermally bonded into 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 form the basis of such a fabric, are joined under high pressure by the hydrojet method. The fabric is characterized by increased strength, breathability and the 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 non-woven material is comparable to swan or eider down. The name "tinsulate" is translated as "thin heat". It consists of the thinnest 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 at a frost of 40o. A strikingly thin thickness does not hinder movement and allows you to freely ski or run.
The negative qualities of thinsulate include its ability to accumulate static electricity. But with the help of appropriate processing, this problem can be eliminated.
Isosoft
Another modern insulation, which was developed by the Belgian concern Libeltex, the largest manufacturer of nonwovens. Isosoft consists 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 warming capacity is 10-12 times higher. The material has all quality certificates, so it can be used without fear even in children's clothing.
Isosoft easily tolerates washing in the machine, without getting lumpy and without penetrating the front side of the product. Clothing dries quickly and returns to its original shape. The disadvantage of the material can only be considered its high cost, but this is more than compensated by its excellent performance and durability.
From thin and delicate rabbit and goat down, a beautiful material called felting is obtained by felting. It is used for the manufacture of outerwear, shoes, hats, children's toys and decor items.
Sometimes, to give the product additional strength and resistance to deformation, viscose or synthetic threads are added to the fluff. 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 when cutting, and looks the same both from the front and from the wrong side.
It's important to know! When washing, felt products can shrink and shed. Therefore, to care for them, it is best to use dry cleaning using special products.
Nonwovens, the list of which becomes more extensive every year, are rightly considered the product of tomorrow. The numerous advantages that they possess make them indispensable in various spheres of human life.
NON-WOVEN MATERIALS (CLOTH)
Non-woven fabrics are obtained by methods that exclude the processes of weaving and spinning. Flat nonwovens are produced by bonding fibrous webs with liquid and foam binders.
Nonwovens- flexible and durable products, of relatively small thickness, relatively large width and indefinite length, formed from one or more layers of textile materials (fibers, threads) fastened in various ways.
PRODUCTION OF NON-WOVEN FABRICS. Obtaining nonwoven materials includes: the formation of a web of fibers evenly distributed in it or the formation of a network of longitudinally and transversely laid threads; bonding fibers in a canvas or threads in a mesh; finishing (if necessary) the resulting canvases in order to give them certain properties.
Non-woven fabrics can be produced in various ways: mechanical, physical-chemical and combined.
· Mechanical method of production. According to this method, non-woven fabrics are obtained by bonding a canvas, a system of threads, textile fabrics and / or combining them with other (so-called carcass) materials. Bonding occurs due to the forces of friction and adhesion of various components to each other when the working bodies of the equipment act on the fibrous material. According to this method of production, 4 groups of canvases are distinguished: knitting-stitching, needle-punched, felting and inkjet fabrics.
The knitting-and-stitching method is based on the principle of sewing a system of warp and weft threads with parallel lines of stitches of various weaves. In contrast to the weaving process, where the fabric is formed by interlacing two systems of warp and weft threads, three systems of threads are involved in the development of tufted fabrics.
Knitting stitch canvases are divided:
canvas-stitched fabrics that are made by stitching a fibrous canvas with threads that are fixed on a knitting and stitching machine with a system of threads of any knitted weave. A feature of this type of canvas is the presence of a large zigzag chain. They are used as heat-insulating (for example, batting), packaging materials, bases in the production of artificial leather;
thread stitching fabrics entirely made up of filaments. They are formed by stitching a system of two threads - longitudinal and transverse - with a third system on a knitting and stitching machine by knitting them. They have a porous structure. This is how decorative canvases, towels, outerwear are obtained. ;
fabric stitching canvases in their structure they can be terry and pile. They are made on the basis of a light frame, stitched with a system of pile threads. The frame can be fabric, knitted fabrics, thread-stitched fabrics. As characteristics of non-woven knitting-stitched fabrics, the stitching density along the length, along the width, the length of the thread in the loop is used.
Needle-punched fabrics. The needle-punched technology for the production of non-woven fabrics consists in entangling the fibers with each other when piercing the canvas with special notched needles using needle-punching machines. As a result, a very dense spatial structure is formed, which is characterized by high strength to mechanical stress. This technology produces felts up to 15 m wide for paper machines, technical “sleeves”, patterned loop materials, embossed floor coverings, products with a given shape, blankets, filters. The most commonly used technology in their production "spunbond", which allows to provide high physical and mechanical properties (in particular, isotropy), as well as resistance to various chemical compounds (alkalis, acids). The resulting material is not subject to decay, the effects of fungi and mold, root germination. Such canvases include needle-punched synthetic winterizer, he looks more dense and outwardly seems less warm. The links between the fibers are established on special equipment with needle combs that intertwine the fibers of the outer layers. Such a synthetic winterizer guarantees the preservation of its properties after washing.
Felting and felt cloths are made by repeated mechanical impacts on the canvas and compaction of the fibrous mass of the canvas under the combined action of moisture, heat and mechanical stress. These are, as a rule, wool fibers that can be felted in a humid environment with elevated temperatures. These include: felt, felted shoes, woolen technical felt and products made from it.
Inkjet canvases. The method is based on fastening a fibrous web with thin jets of liquid or gas, which are ejected under pressure at high speed. The most common use of water jets. One of the representatives of inkjet fabrics is a non-woven fabric made of microfibers - microspun.
· Physico-chemical methods for the production of non-woven materials. These methods are considered the most progressive. They are based on fast physical and chemical processes of fastening fibers (or threads) due to adhesion (gluing) forces. Gluing can be carried out: liquid binders solid binders thermal bonding bonded paper-making method spunbond method. There are various methods for obtaining canvases using this technology: impregnation with binders, formation of thermal bonding from a melt or polymer solution, etc. The best known is the method of obtaining non-woven fabrics by impregnation with binders, or adhesive method.
Bonding with liquid and solid binders. Binders, when heated or dissolved, soften and stick together the structure of the web. They can be introduced into the polymer structure at the stage of preparation of the fibrous mass in the form of powder, mesh, film, etc. This technology is used to obtain the so-called glued non-woven materials. Their basis is a fibrous canvas formed from homogeneous fibers or their mixtures with a mass of 1 m 2 from 10 to 1000 g. The fibers in the canvas are fastened with liquid polymer binders, most often with aqueous dispersions of polymers (latexes based on rubbers or thermoplastic polyacrylates). Bonding with solid binders is based on the bonding of fibers and threads of the fabric with thermoplastic binders when heated. They are introduced into the structure of fabrics in the form of powder, fusible fibers, etc.
Papermaking method The production of nonwoven fabrics is based on the formation of a fibrous web by a hydrodynamic method from a suspension of fibers containing a binder. With this method of producing nonwoven fabrics, various raw materials, short fibers and high-performance equipment can be used. In this way, fabrics for medical purposes are obtained.
Spunbond method based on gluing fibers or threads immediately after they are formed from polymer solutions or melts. At the exit from the spinnerets, they are almost simultaneously laid in the canvas. The main advantage of the spunbond method over other technological processes is the exclusion of the preparation of fibrous raw materials, the combination of the stages of obtaining fibers and canvas.
· Combined method- this is a method that combines mechanical and physico-chemical technologies (needle-punched or jet bonding of the canvas with its further connection with binders; stitching the frame with pile threads while simultaneously fixing them with binders).
This method may include the method of electroflocculation, in which short fibers are oriented applied to a base (fabric, knitted fabric) pre-coated with glue in a high-voltage electric field in an electroflocculation machine. This method is used to make artificial suede, furs, flocked carpets, etc.
A variety of methods for the production of non-woven fabrics is the basis for the classification of non-woven fabrics.
CLASSIFICATION OF NON-WOVEN FABRICS. Non-woven fabrics are classified according to the method of production. The classification of methods for the production of nonwoven materials is shown in Fig. 11.1
Rice. 11.1. Classification of nonwoven fabrics
RANGE OF NON-WOVEN FABRICS. Range stitched materials- These are materials such as fabrics and batting. Clothes are made from canvas-stitched non-woven fabrics: dresses, bathrobes, children's, sportswear, suits, coats; used for the manufacture of children's and sportswear:
thread-piercing nonwoven fabrics. Dresses, blouses, shirts, suits, children's products, as well as household items are made from thread-sewn non-woven fabrics;
woven non-woven fabrics. From fabric stitching non-woven fabrics are made terry: dresses, bathrobes, children's products; pile: coats, sportswear .
Needle punched nonwoven fabrics used for the manufacture of heat-insulating gaskets, coat hangers for garments.
From felted non-woven fabrics produce clothes, household items, shoes, hats, technical products.
Glued non-woven fabrics in clothing, it is used for a lining that provides and maintains the shape of the product. Gasket materials are divided into non-adhesive and adhesive. Non-adhesive gasket materials include linen beading, cotton calico madapolam, calico, etc. Adhesive materials include: interlining, proclamelin, glued fabric "Syunt", felt, dublirin, glue edge, glue gossamer, etc.
Interlining, used for laying in the sides, collars, straps, valves, slots, leaflets near the pockets, in the bottom of the sleeve of the product.
Proclamelin used as lining for dresses, suits, coats.
Glued fabric "Syunt" used as a lining material for women's summer coats, suits and faux fur coats . Filz - needle-punched glued fabric used in the manufacture of jackets as a side lining for lower collars.
Dublerin - these are adhesive interlining materials on a woven or knitted basis, which are used for duplicating stretch materials and knitwear, as well as for parts of large sizes .
glue thread - monofilament in the form of a vein of thermoplastic polymer. It is used for fastening folded and turned edges of parts.
Gossamer hotmelt is a non-woven adhesive material made from a melt by the method of aerodynamic molding. Is issued on a paper basis and without paper, from 10 to 40 mm wide. It is used for bending the bottom of products.
Adhesive mesh made of high pressure polymers, has a cellular structure, designed for dimensional stability of small parts.
Glue edge protects armholes, necklines, lapel fold lines, sides, etc. from stretching. It is more elastic, easier to fit along the rounded lines of the product. Adhesive edge width - 10, 15 and 20 mm. It can also be cut obliquely and reinforced with stitching or soutache.
STRUCTURE OF NON-WOVEN FABRICS. The structure of nonwoven materials is complex and varied. Most nonwoven fabrics are made from fibrous canvas. The structure of the canvas determines the nature of the location of the fibers and their orientation in the canvas. The characteristics of the structure of the canvas are the coefficient of curvature of the fibers and the orientation of the fiber. The fiber orientation is expressed by the angle of inclination of the fiber to the longitudinal direction of the web.
Canvas-stitched fabrics have a porous and loose structure. Thread-piercing - porous structure. Fabric-stitched fabrics are made of terry and pile.
As a characteristic of the structure of knitting-stitched non-woven fabrics, the following are used: the density of stitching along the length P D and the width P W, the length of the loop l p, the length of the stitching thread in 1m 2. The length of the sewing thread is determined by the formula:
The structure of needle-punched fabrics is characterized by the frequency of punctures per 1 cm 2 of the fabric area, and this indicator is called the piercing density.
A feature of the structure of glued fabrics is the presence of zones of bonding fibers or threads with binders.
· HOLOFIBER- these are non-woven fabrics made of hollow fibers (in the form of microsprings located vertically in the fabric), obtained by thermal bonding. The literal translation of the word Hollofiber®: Hollow (hollow or hollow), fiber (fiber). Such non-woven fabrics and fillers from hollow fiber are produced by the Non-woven Fabrics Plant "Termopol-Moscow" under the brand name HOLLOFIBER®. Hollofiber fibers can quickly recover their shape after being crushed and have a high resistance to retaining their shape over time. Cloths from these fibers are produced with different surface density, width and height.
The following types of non-woven fabrics and fillers have been developed: Hollofiber soft, Hollofiber medium, Hollofiber hard.
· HOLOFIBER SOFT - this is a soft, elastic fabric that provides unique thermal control properties in products, while allowing the body to “breathe”, retains its shape, and the product can be washed. The canvas is used in the manufacture of outerwear, tourist equipment without “stitching”, which significantly reduces labor costs in the sewing industry.
· HOLOFIBER MEDIUM - this canvas is especially sensitive to the microclimate of the human body and therefore the most convenient, environmentally friendly, non-allergic material for the manufacture of children's sets. The material has a quick recovery after crushing, which allows you to make high-quality furniture without "washed places" and "extra folds" on the upholstery after a long sitting, and is also the best filler for creating a soft toy.
· HOLOFIBER HARD - It is a rigid synthetic non-woven fabric. It is used in particularly heavily loaded elements of upholstered furniture, car interiors, etc., as a good substitute for foam rubber (for large thicknesses), for the manufacture of mattresses, and is a good sound and heat insulator.
· PERIO TECH - This is a non-woven material made of polyester fibers bonded together by a thermal method, consisting of 3 layers: two reinforcing and one carrier. The name PerioTek is made up of the first syllables of the phrase PERI odically ABOUT oriented TEK stur. The uniqueness of the PerioTec technology lies in the vertical laying of the fibers, which gives the nonwoven material an improved volume recovery, which allows the product to retain its shape. Polyester fiber with a fusible coating is used as a binder material. The structure of the PerioTek filler resists compression more actively, directing forces directly towards the pressure (like a spring). PerioTek is produced by the Ves Mir nonwovens factory based on various synthetic and natural fibers, with a density of 150 to 750 g/m², up to 2.2 meters wide and is used as a filler for upholstered furniture and mattresses.
· HOLLO-TECH TM - is a homogeneous canvas, consisting of several layers arranged parallel to each other. HolloTech got its name from the English words "hollow" - hollow, "tech" - texture and because it consists of hollow spirally crimped polyester fibers coated with silicone. Polyester fiber with a fusible coating is used as a binder material. To reduce friction between the layers and increase the uniformity of the web after formation, the layers are partially mixed with each other.
HolloTech is used as a filler in the production of upholstered furniture; for the production of bedding - bedspreads, blankets and pillows; with low fiber migration, it is used in the production of outerwear.
· Sintepon - high-quality non-woven filler is made of polyester fibers, the bonding of which is carried out by a thermal method. Polyester fiber with a fusible coating is used as a binder material. Using additional technological equipment, a fabric structure is obtained that has a larger volume at a lower density: Sintepon Economy ™ ; Sintepon Standard ™ ; Sintepon Wool; Sintepon Melange ™ (contains natural cotton). All types of synthetic winterizer can be reinforced with an additional layer. The synthetic winterizer is used for insulating lining in clothes, upholstered furniture, mattresses, bedding, quilted, sewing, decorative products of a new generation.
· Shelter™ - insulating non-woven filler. Shelter got its name from the English word "shelter" - a reliable shelter - this filler is environmentally friendly and does not cause allergies; has good thermal insulation, air permeability, moderate elasticity, uniform structure, good drapeability, reduced fiber migration.
There are several types of Shelter materials: Shelter Standard ™; Shelter Soft ™ ; Shelter Light ™ ; Shelter AS ™ (with enhanced antistatic properties); Shelter AB ™ (obtained by nanotechnology, acquires antibacterial resistance). In accordance with GOST 29335-92 "Men's suits for protection against low temperatures", Shelter insulation is recommended to be used in conditions of a special climatic zone, making it indispensable in the manufacture of special insulated clothing for workers in the gas, fuel and oil industries.
· FIBERTECH™- this is a non-woven material, which is a three-dimensional layer of thin hollow fibers with three-dimensional thermal bonding elements, specially treated with silicone. These fibers move independently of each other, and as a result, FIBERTEK insulation does not stray, does not cake and retains its shape even after getting wet. To achieve the required strength and stability, the surface of the layer is reinforced with polypropylene fiber and mechanically quilted. FIBERTEC is produced in the form of layers of various densities, widths and thicknesses. Layers can be made without an outer shell, with a one-sided and two-sided outer shell with quilting at intervals of 10 - 25 cm.
· Spunbond - 100% polypropylene non-woven fabric. One representative of these nonwoven materials is the " Polartec". Nonwoven materials obtained by the spunbond method represent a fundamentally new class of products that occupy an intermediate position between paper and fabrics. Using this technology, fabrics can be produced with a surface density of 5 to 800 g/m 2 and a thickness of 0.11 to 4 mm. With the help of additives, it can be given various properties: hydrophilicity, hydrophobicity, antistatic. Spunbond fabrics are used for the production of sanitary and medical clothing; for the production of disposable clothing; home textiles; mattress production; for packaging products.
· Fleece- This is a synthetic "wool" made of polyester, which does not absorb moisture, but conducts it. In addition, products made from this material are light, durable and perfectly retain heat, thanks to the large amount of air contained in the so-called "air chambers". It can also be single or double sided. Single-sided is usually used for sewing underwear and shirts, double-sided for warmer clothes.
Nonwovens are called textile fabrics made from one or more layers of textile materials (sometimes in combination with non-textile materials), structural elements Ry which are attached in various ways.
The basis of non-woven fabrics can serve as a fibrous canvas, a system of threads, fabric or knitted fabric and various Them combinations. IN non-textile materials, in particular, polymer films or nets, can also be used as structural elements. The fastening of the structural elements of non-woven fabrics is carried out in various ways: knitting with threads and fibers, needle punching, gluing, welding, felting, etc.
A variety of methods for the production of non-woven fabrics is the basis for their classification (Scheme 1.5). According to the bonding methods, non-woven fabrics of three classes are distinguished: bonded by mechanical, physico-chemical and combined methods. The classes of paintings, in turn, are divided into subclasses. Further, the division of the canvases is carried out into groups depending on the type of material base: canvas, thread system, carcass and their difference in combination.
TThe structure of non-woven fabrics. The structure of nonwoven fabrics is largely determined by the method of production. The technological process of manufacturing non-woven fabrics is
Two stages: preparation of the base (canvas, thread system, fabric No. etc.) and its fastening.
Lj The preparation of the fibrous web consists in selecting a mixture of rolocone and threads, loosening, mixing, cleaning and carding the fibrous mass and shaping the web. For production
The structure of non-woven fabrics is widely used natural fibers and threads (cotton, wool, linen) and chemical (viscose, nylon, lavsan, nitron, etc.) in various combinations, which makes it possible to obtain materials with various properties. In the production of non-woven fabrics of some types, fibers of both standard length and short (at least 3 mm), spinning production waste, waste fibers are used, which makes it possible to use fibrous raw materials with great economic effect. For the formation of fibrous mass, depending on the type of processed raw materials, machines are used in the opening, scutching and carding departments of spinning production.
The formation of the canvas can be carried out in several ways: mechanical, aerodynamic, hydrodynamic and electrostatic. With the mechanical method, the webs from the carding machines are stacked on top of each other with the help of conveyor belts.
Depending on the direction of laying the battens, there are canvases with different orientations of the fibers in them: longitudinal, longitudinal-transverse, diagonal. All oriented webs have a layered structure.
With the aerodynamic method, the fibrous web is formed by an air flow from individual fibers on the surface of a mesh drum (condenser) or a conveyor belt. The hydrodynamic method of formation is based on the dispersion of fibers in a liquid and their subsequent deposition and placement on mesh conveyor belts. With the electrostatic method, the formation of a fibrous web occurs by moving and depositing electrostatically charged fibers in an electric field. With aerodynamic, hydrodynamic and electrostatic methods of formation, layerless canvases are obtained with a non-oriented, chaotic arrangement of fibers.
The nature of the location of the fibers in the canvas largely determines many of the physical and mechanical properties of nonwoven fabrics, in particular their strength in the longitudinal and transverse Directions. Often, to increase the strength of the fibrous canvas, a frame is placed on its surface or between layers in the form of a transverse system of threads, a mesh of warp and weft threads stacked on top of each other, a rare fabric or knitwear. In the preparation of systems of threads, fabrics, knitwear, various types of Yarns and complex threads are used. These types of base non-woven fabrics are made, respectively, at spinning, weaving and knitting enterprises. Structural elements of the basis of non-woven fabrics are fastened by mechanical, physico-chemical or combined technology.
mechanical technology bonding is based on the impact of the working bodies of the equipment on the processed fibrous material. In this case, knitting-stitching, needle-punching, jet and felting methods of connection are used, of which the knitting-stitching method is most common.
The knitting and stitching method consists in knitting the base in the form of a canvas, a system of threads, fabric, etc. with threads. The warp is knitted with threads on a knitting machine, which is a type of knitting warp knitting machine, using grooved needles. Hooks of needles for simplification of piercing are pointed. For knitting the base of non-woven fabrics, chain weaves, tights, cloth, charme, sirloin, plush, combined, etc. are used. Canvas-stitched non-woven fabrics are produced on knitting-and-stitching machines. The fibrous canvas (Fig. 1.46) is fed into the knitting zone with the help of a conveyor belt. Grooved needles pierce the fibrous canvas from the bottom up and capture the knitting threads that feed the eyelets. The threads are unwound from the beam. During the reverse stroke, the slotted needles pull the threads through the canvas, forming a warp-knitted weave. The finished fabric is wound on a commodity roller. A canvas-stitched fabric is a canvas enclosed inside a rare knitted weave, on the front side of which there are looped columns, and on the wrong side - zigzag broaches (Fig. 1.47). Its variety is a canvas, which is a fibrous canvas knitted with the fibers of the same canvas. To obtain such a fabric of sufficient strength, it is necessary that the length of the fibers in the canvas be 60-120 mm, and the orientation of the fibers is predominantly transverse.
Rice. 1.46. Scheme for obtaining a non-woven fabric knitting-proshpv-
New way:
1 - conveyor belt, 2 - Canvas; 3 - pavoi; 4 - knitting thread; 5- ears; b - groove needle; 7- canvas-stitched gu-
Lotno; 8 - commodity kalik
■ <А .|1t«.I. H. .V.-I. I I IG *
Rice. 1.48. Thread-sewn non-woven fabric
There are one (weft) or two (weft and warp) systems of threads, which are knitted by the third system (Fig. 1.48).
Non-woven thread-sewn fabrics can be produced by plush weave, which makes it possible to obtain terry and tufted fabrics.
Frame-stitched non-woven fabrics are obtained in a similar way by knitting loops with elongated broaches on a frame basis. In this case, using threads of various types, it is possible to produce materials such as terry, plush, artificial fur, etc. Fabric (fabric-stitched fabrics), knitwear, and non-woven material are used as a frame base. A variety of frame-stitched canvases are fabrics in which the frame material is knitted with the fibers of the canvas laid on the frame. As a result, fibrous loops are located on the wrong side of the fabric, and a continuous fibrous covering is formed on the front side. In this way, it is possible to obtain lining materials for clothing and artificial fur.
The needle-punched method for producing non-woven fabrics consists in the fact that the fibrous canvas is pierced (punched) with special needles that have a trihedral, square or diamond-shaped blade, on the edges of which there are notches (Fig. 1.49). The fibrous canvas (Fig. 1.50) is fed by means of a conveyor belt to the needle punching area between the Laying and Cleaning tables. The tables have holes for the passage of needles and fixing the position of the canvas when pierced. The needles are fixed on a needle board that moves up and down vertically.
Passing through the canvas, the needles grab the fiber bundles with their notches and drag them through the thickness of the canvas. As a result, in the struct Toure canvas (Fig. 1.51) change the location of the fibers, their orientation. In places of punctures, bundles of fibers are formed, located perpendicular to the plane of the canvas; with the help of these beams
Rice. 1.49. Needle used to produce non-woven fabrics by needle punching
Cove is the binding of the structural elements of the canvas. The fibers are arranged in a bundle in the form of a funnel, expanding at the point where the needle enters the canvas. The bonding strength of the web depends on its thickness and the frequency of punctures: the greater the thickness of the web and the frequency of punctures (and hence the frequency of the fiber bundles), the higher the bonding strength.
The jet method of bonding a fibrous web is based on the action of thin jets of liquid or gas on it, which are ejected from nozzles at a pressure of 1.4 - 32.4 MPa at a speed of 15 - 30 m/s. The most common use of water jets. The canvas is placed on a mesh conveyor and subjected to one-sided or two-sided plow action! water, resulting in entanglement of the fibers in the canvas with the formation of a sufficiently strong material. The supply of water jets can be continuous and pulsating. The bonding strength of canvases depends on the pressure, the number of nozzles per unit area of the canvas, and the speed of its supply to the inkjet device. The structure and appearance of the non-woven material is greatly influenced by the structure of the substrate - the grid on which the canvas is placed. If the substrate has a relief structure, then the water jets, hitting the reliefs, are deflected and act on the canvas for the second time. As a result, the binding compacted fiber bundles are located not only vertically to the surface of the canvas, but also horizontally or obliquely. In this case, the fibers that have fallen into the recess of the substrate are more entangled and form patterned effects on the surface of the web.
Needle-punched and inkjet methods can be considered as ways to pre-bond webs, since the resulting webs have significant elongation and a large proportion of irreversible deformation.
Rice. 1.50, Scheme for obtaining a non-woven fabric by a needle-punched method -
1 - canvas: 2 - transporting LESH-i. 3 ~ laying table; 4 - cleaning table; 5 - needles; 6 - needle board-1
Rice. 1.51. Fiber Orientation in Needle Punched Nonwoven Fabric
The felting method for the production of nonwoven fabrics is one of the oldest methods for producing textile materials. It consists in the compaction of the fibrous mass under the combined action of moisture, heat and mechanical load. The most durable and dense fabrics are obtained from wool fibers - the only type of fiber that has the properties necessary for this method; elasticity, crimp and the difference in tangential resistance along and against the flakes of the fiber surface. The use of other types of fibers is inefficient: the fabrics obtained are easily stratified. In the production of non-woven fabrics, the felting method usually processes a canvas with a carcass laid inside from a system of threads.
Physical and chemical technology The production of nonwoven fabrics is based on the adhesive or autohesive bonding of canvas fibers, a system of threads and textile materials. Adhesive bonding (gluing) of fibers and threads is provided by polymer binders (adhesives). The autohesive connection of fibers and threads at the points of contact occurs under conditions that provide softening of the surface layer of the fibers and their adhesion (welding).
For the production of non-woven fabrics, polymeric binders are used, the share of which in the fabric is about 0.3. They are the same important component of the non-woven fabric as fibers and threads, and provide a strong connection of structural elements. Polymers of Lrex types are used as binders: thermoplastic, thermosetting and based on kau - 1 "Chukov (rubber).
Thermoplastic binders are polymers that, when heated or dissolved, soften and stick together the structural elements of the base. These include polyester - | Linen, polyvinyl acetate, polyvinyl alcohol, polypropylene, roleurethanes, cellulose derivatives, etc. Thermoplastic binders are used in various forms: polymer solutions, aqueous dispersions, powders, fibrids, fibers, films, meshes. They are preliminarily applied to fibers from a melt or solutions (combined fibers) or introduced into the composition of the fibers during their [spinning (bicomponent fibers).
K, Thermosetting binders harden as a result of chemical reactions with the formation of an irreversible three-dimensional structure - ■rt. They are based on phenol-formaldehyde, epoxy, polyester and other synthetic and natural resins. In the production of household non-woven fabrics, thermosetting binders are rarely used, as they give the fabrics increased rigidity.
Rubber-based binders harden as a result of vulcanization. They are widely used in the form of aqueous dispersions of synthetic rubbers (latexes) with the addition of thermosetting binders.
Gluing with liquid binders is one of the most common methods for obtaining glued non-woven fabrics. It consists of the operations of impregnating the base (canvas, thread systems, etc.), drying and heat treatment. The introduction of a binder into the base of the nonwoven fabric can be carried out in various ways. When the canvas is completely immersed in the solution, followed by squeezing, the binder is evenly distributed throughout the base with the formation of the maximum number of bonds between the fibers, which gives the materials increased rigidity. During padding, the canvas is passed between two rollers of the machine, where a liquid binder is fed. With this method, a foamed binder is often used, which gives the finished web increased elasticity, porosity, breathability and reduces its surface density. Impregnation with a binder sprayed over a moving web, using vacuum suction to penetrate deeper into the structure, results in a reduction in the number of glues and a softer web.
A similar effect can be achieved by impregnating the canvas by printing - local application of a thickened binder to the canvas in a specific pattern in the form of dots, rings, loops, rhombuses, etc. Subsequent heat treatment promotes strong bonding of the structural elements of the non-woven fabric as a result of rubber vulcanization or softening of the thermoplastic binder . However, during drying and heat treatment, migration of binder particles to the surface layers is possible, which can cause delamination of the fibrous web.
Bonding with solid binders is based on fastening the fibers and threads of the base of the nonwoven fabric with thermoplastic binders when heated, which are introduced into the base structure at the stage of preparation of the fibrous mass in the form of powder, low-melting fibers, fibrides, combined and bicomponent fibers; when forming a canvas - in the form of frame elements: films, nets, systems of fusible threads; into the finished canvas - in powder form. Heating is carried out by thermopressing or thermocontact welding over the entire area; if in separate places, then engraved shafts or electrodes of various shapes are used. When the powder particles are heated, it is easy
fusible fibers and threads, fibrids, films melt and form bonds between the fibers and threads, with part of the binder remaining outside the bonds. Unlike them, combined and bicomponent fibers do not lose their shape when heated, but only melt over the surface and form gluing only at the points of contact of the fibers, creating an ideal point structure of the glued canvas. By changing the thickness of the fusible sheath of combined fibers, their ratio with ordinary fibers in the canvas and the pressing mode, it is possible to obtain materials of various structures: from bulk porous materials to materials consisting of a continuous film of binder reinforced with fibers.
The papermaking method for producing nonwoven fabrics is based on the formation of a fibrous web by a hydrodynamic method from a suspension of fibers containing a binder. The technological process consists of the preparation of a suspension of fibers, the casting of the web on a paper machine, dehydration, drying and heat treatment. This method is very promising, as it allows the use of any raw material, short fibers (2 - 6 mm) and high-performance equipment. At present, medical fabrics are obtained in this way (for linen, gowns, napkins, etc.).
The spunbond method for the production of nonwoven fabrics consists in the aerodynamic formation of a fibrous web directly from a melt or polymer solution (Fig. 1.52). Thin streams of polymer come from the holes of the spinneret into the blowing shaft, where, under the influence of the air flow, the threads are pulled and hardened. From the shaft, the threads are fed to a conveyor belt, where a fibrous web is formed. There are two options for forming the canvas: hot and cold. In the hot mode, the threads at the time of laying are softened to such an extent that the formation of glues is possible at the points of contact due to autohesion without the introduction of a binder. However, in this case, the mechanical properties of the filaments are very low, because due to the weak drawing and the relaxation that occurs during laying, the structure of the fibers is poorly oriented. In a similar way, an adhesive web is obtained for gluing Clothing Details. When cold forming
Rice. 1.52. The scheme for obtaining a non-woven fabric by a spunbond method:
1 - transporting mite; 2 -
blower shaft; 3 - streams of polymer; 4- die
In the fabric of the canvas, the threads completely harden by the time of laying, so a binder is introduced to fasten them, and then heat-fixing is carried out.
The spunbond method for producing nonwoven glued fabrics is one of the most promising. By Experts predict that in the coming years, the volume of production of nonwoven fabrics by the spunbond method will reach 30% of the total volume and will continue to increase in the future. This is due to the high productivity of the plants, the simplification of the process of forming the canvas, the use of chemical threads and the possibility of producing a wide range of canvases.
Combined technology The production of nonwoven fabrics is based on a combination of mechanical and physico-chemical bonding methods. Options for combinations of methods can be different: for example, preliminary needle-punched or jet bonding of the canvas and subsequent connection with its binder; stitching the carcass with pile threads and fixing them with binders, etc. The combined method includes blasting a canvas containing low-melting fibers, fibrids or bicomponent fibers with hot air or water. In this case, not only the entanglement of the canvas fibers occurs, but also their thermal bonding.
The main characteristics of the structure. Until now, there is no well-established classification of the characteristics of the structure of nonwoven fabrics, which is associated with the constant improvement of their manufacturing technology and the emergence of new types of structures. Therefore, at present, the structure of nonwoven fabrics is characterized by the parameters of the structure of their base (fibrous canvas, systems of threads, fabric, knitwear, etc.) and the parameters of the fastening elements (piercing, gluing).
The structure of the fibrous canvas is determined by the linear density of the fibers and threads, the degree of their straightening and orientation in the canvas, the number of layers of batting. The degree of straightening of the fibers is characterized by the coefficient of curvature FROM, Which is the ratio of the true length L„ of the fiber to the distance but between fiber bonding points or fiber ends:
The orientation of the fibers in the web is estimated by the angle p of the fiber to the longitudinal direction of the web. Since the location of the fibers in the canvas is not the same, it is customary to determine the indicators of these characteristics for a large number of fibers and plot their distribution curves, according to which it is possible to establish the predominant value of the curvature coefficient and the orientation angle.
If systems of parallel threads, fabric or knitwear serve as the basis of a nonwoven fabric, then the characteristics of the structure of this fabric are the number of threads along the length and width, as well as the generally accepted characteristics of the structure of the fabric and knitwear.
The method of fastening the elements of its base has a significant influence on the nature of the structure of the non-woven fabric. With the knitting-stitching method of fastening, the characteristics of the stitching structure are similar to the characteristics of the knitwear structure. This is the number of loops in length Px and width Fri fabrics on a conditional length of 50 mm, the length of the thread in the loop / p. In addition to them, the length of the sewing thread L, mm, per 1 m2 of the web is determined:
L = 0.4 YADLSh/P
And the work Y,%, threads:
Y \u003d 100 (1, - L2 )/L,
Where Lx - thread length, mm; b7 is the length of the section of the fabric from which the thread is taken out, mm.
The structure of the needle-punched fabric is characterized by the frequency of punctures per 1 cm2.
A distinctive feature of glued non-woven fabrics obtained by physical and chemical technology is the presence of zones of bonding (gluing) of fibers or threads with binders. The structure of the gluings is characterized by the design, appearance, size, distribution and number of fibers in the gluing. There are several types of glues found in the structure of nonwoven fabrics.
Contact gluing (Fig. 1.53, a) is formed by a layer of binder between the fibers at the points of their contact. They are characterized by minimal size and low strength; occur mainly when combined and bicomponent fibers, fibrids are used as a binder and during hot forming of a spunbond web.
Gluing-couplings (Fig. 1.53, b) form a stronger connection, but less mobile than contact ones, since the film is connected
Zuyushego envelops the fibers at the intersections. These gluings occur when canvases are bonded with liquid and solid binders.
Lamella gluing in the form of plates (Fig. 1.53, in) are, as it were, couplings increased along the length of the fibers; they sharply limit the mobility of the fibers in the joint. Lamella gluing occurs mainly when using latexes as a binder.
Aggregate gluing fastens more than two fibers arranged in parallel (Fig. 1.53, G) or chaotically (Fig. 1.53, e). With a parallel arrangement of fibers, the gluing design combines a contact riveting and a sleeve, such gluing has maximum strength and minimum mobility. With a random arrangement of fibers, the bonding strength is slightly lower.
In non-woven fabrics, various types of gluing can occur simultaneously, the proportion of which depends on the type of fibers, the structure of the canvas, the type of binder, and the fabric manufacturing conditions. There are three main types of structure of non-woven glued materials: segmented, agglomerated and dotted.
In the segment structure (Fig. 1.54, but) the main share is made up of aggregate and lamellar glues, which tend to form a continuous three-dimensional network structure inside the material. In materials with a segment structure, the properties are determined to a greater extent by the properties of the binder than by the properties of the fibers, the mobility of which is extremely low. The materials are rigid and have low permeability.
The agglomerate structure (Fig. 1.54, b) is characterized by the presence of predominantly gluing-couplings, as well as random accumulations of a binder of various shapes. Compared to the segment structure, it is more mobile and less rigid.
In a dot structure (Fig. 1.54, in) there are contact gluing and gluing-couplings. The binder is most rationally distributed in it. The properties of a non-woven fabric of a dotted structure are determined by the properties of the constituent fibers, the nature of the location and the strength of the glues. Such canvases are characterized by softness, mobility, good permeability.
The structure of glued non-woven fabrics is characterized by the proportion of the binder in the total mass of the fabric and the coefficient of use of the binder Xl, which is defined as the ratio of mass Moscow or volume USKYA binder in gluing to the total mass MSV Or the volume VCtt of the binder in the web;
TO= L//M = V /V
Non-woven materials are called a special kind of fabrics made without the use of flat weave technologies. To date, there are many types of such products, as well as methods for their manufacture. The scope of the material of this variety is also wide. Most often, non-woven fabric is used in construction and agriculture, as well as in tailoring.
A bit of history
For the first time, non-woven material was made in the second half of the 19th century in the USA. The first canvases of this variety were made from starch fastened together. This material, called pellone, did not receive special 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 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 our country. It was widely used in our country 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 factory of non-woven materials "Ves Mir", founded in 2000.
Density
Non-woven material can be made in different ways, have different thickness, appearance and purpose. However, the main characteristic of such canvases in most cases is strength. The latter, in turn, depends on the surface. This parameter in groups of different purposes can vary between 10-600 g/m 2 . So, for example:
Canvas non-woven material usually has a density of 235-490 g/m 2 .
For a needle-punched fabric, this figure is 210 g/m 2 .
The density of fabric-piercing materials is 216-545 g / m 2.
Interlining has a surface density of 90-110 g / m 2.
For threaded fabrics, this figure is 63-310 g/m 2 .
Density of glued non-woven material - 40-330 g/m 2 .
Fabrics of this type can be produced mechanically or adhesively. 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 methods of production
The fastening of the base of the non-woven material using this technology is carried out using additional threads. In a mechanical way, for example, canvas-stitched materials are made. In this case, the warp fibers are fastened together by stitching them with threads. When using needle-punched technology, the elements forming the canvas are preliminarily entangled with each other. The result is a rather dense fabric. To give greater strength, it is stitched with thick threads. In this case, special tools with notches are used. The needle-punched method of making canvases is currently the most popular. This technology is used by every nonwovens plant.
Thread-piercing materials are made by passing through the warp with one or more fiber systems. Such a canvas differs from a canvas-stitched one primarily in appearance. The material of this group is similar to terry cloth.
On sale today there are also mechanically produced fabric-stitched fabrics. This variety is produced on a very light basis also by stitching it with a pile thread system. Such canvases can be both smooth and terry.
Glue production of nonwovens
This technology is used in the manufacture of most varieties of nonwoven materials. The bonding of the fibers in the canvas in this case is carried out by impregnating them with various kinds of adhesive compositions. Most often, synthetic latex is used for processing. Another common technology is hot pressing. In this case, the fibers are glued together with thermoplastics at very high temperatures.
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 the pellet 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 fabrics
Such non-woven material is distinguished by its large thickness, massiveness and friability. Its main advantage is high heat-shielding properties. Canvas-stitched fabrics are very dense and wear-resistant materials that can shrink significantly. They are most often used as lining in the manufacture of clothing. They are also sometimes used as the basis for 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 material include resistance to washing and dry cleaning. Needle-punched fabrics are usually used for floor coverings. Like canvas stitching, they are also used to make linings for coats, jackets and fur coats. However, in the latter case, the needle-punched non-woven material usually has to be additionally impregnated with adhesive compositions. The fact is that its fibers are rather rigid, and therefore, in a free state, they are able to penetrate through the top and spoil its appearance.
It is the needle-punched method that also produces the most common non-woven material - dornite. Geotextiles are used when laying out lawns, building 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 canvas is still made by the adhesive method (hot pressing).
The use of thread and fabric-stitched fabrics
Both of these varieties are also quite in demand in the industry. The main advantage of threaded fabrics is considered to be a variety in appearance. This method can produce both very thin translucent materials and massive furniture. Suits, evening dresses, casual wear, scarves, non-woven napkins are often made using this technology.
The advantages of fabric-piercing materials are stable structure and hygiene. According to such an indicator as wear resistance, they are superior to all other types of nonwoven materials. This fabric is used mainly for sewing bathrobes and beach suits.
Where are adhesive tapes used?
Most often, such non-woven material is made from a mixture of cotton and nylon fibers. It is usually used in tailoring. For example, it is inserted into collars, straps and slots to give the latter rigidity. Materials produced on paper machines are most often used for the production of various kinds of medical dressings.
As you can see, the scope of non-woven fabrics in our time is really very wide. Their excellent performance characteristics make them indispensable for sewing many types of clothing, growing plants, arranging drainage systems, etc. The production technologies for such materials are not particularly complex, and therefore their cost is usually low. Basically, this explains the extraordinary popularity of this variety of canvases.