Basic Spinning Processes

FABRIC PRODUCTION TECHNOLOGY

First, textile threads are produced from raw materials - fibers or filaments - yarn or filament threads. Yarn is obtained by spinning fibers. Complex threads are twisted from several elementary threads.

The resulting yarns or filament threads are then produced into fabric through the weaving process. In this case, a raw fabric is obtained, which is subjected to finishing, giving it a beautiful presentation.

The fibrous mass of natural fibers, after collection and primary processing, is supplied to the spinning mill. Here, a continuous strong thread - yarn - is produced from fibers of limited length. This process is called spinning. Along with natural fibers, staple chemical fibers are also processed in spinning mills.

The raw materials for spinning are textile fibers: cotton, flax, wool, waste from silk weaving and sericulture, and various chemical fibers.

The spinning process can be divided into three stages:

Preparation of the fibrous mass and the formation of a tape from it;

Preparation of sliver for spinning and pre-spinning;

Spinning.

The stage of preparing the fibrous mass and forming a tape from it includes the processes of loosening, mixing, scuffing, and carding.

When loosening, the tightly compressed mass of fibers is divided into small shreds for better mixing and cleaning the fibrous mass from impurities. Loosening is carried out on feeder-rippers.

Individual lots of cotton, wool and other fibers vary in length, thickness, moisture content and other properties. Loosened fibers from different batches are mixed together in order to obtain large batches of raw materials that are homogeneous in their properties. Therefore, several batches of fibers are usually mixed. Fibers of different natures are also mixed to obtain yarn with certain properties. The main mixing takes place on the mixing grid. After mixing, the fibrous mass is sent to scutching.

Scuffing provides further loosening and intensive cleaning of the fiber mass from impurities. The loosened and purified fibers are converted into canvas, which is wound into a roll. The process is carried out on scattering machines.

In order to separate small shreds and tufts of fibrous mass into individual fibers, the canvas is carded. Remove small, tenacious impurities remaining after the processes of loosening and scuffing. When carding, a fly or roving is formed from a thin layer of combed fibers. Carding is carried out on carding machines, in which the fibrous web passes between the surfaces of the card belts, covered with thin sharp metal needles. When leaving the carding machine, a thin combed layer of fibers - a carded card - is passed through a funnel and converted into a tape of non-uniform thickness, which is a bundle of fibers oriented in the longitudinal direction.

To obtain roving, the batt fleece is not formed into a tape, but is divided into narrow strips, which, after compaction, are converted into roving.

The second stage of spinning production consists of preparing the sliver for spinning and pre-spinning.

Preparing the sliver for spinning consists of straightening and stretching the sliver. First, fold 6-8 tapes together, aligning them in thickness. To obtain mixed yarn, ribbons of different fiber compositions are combined. The folded tapes are pulled out evenly, while the tape becomes thinner and the fibers are straightened and oriented.

The tapes are aligned and drawn on draw machines, which are equipped with several pairs of rollers rotating at increasing speed. Passing between the rollers, the tape gradually becomes thinner and the fibers in the tape are oriented in the direction of movement. Processing can be carried out sequentially on several machines to obtain increasingly thinner sliver. High-drawing draw frames are widely used, replacing several draw frames.

Pre-spinning is the gradual pulling of the sliver into the roving. It is carried out on roving machines, where the strips are finally drawn into a roving of the required thickness, slightly twisted to strengthen it, and also wound onto a package of a given shape and size.

The third stage is spinning, during which the final thinning of the roving and its twisting occur, i.e., turning the roving into yarn, as well as winding the yarn onto a package of a given shape and size. Spinning is performed on spinning machines.

The raw materials entering the spinning production have different qualities: length, thickness, fiber crimp. From thin, long-fiber raw materials, thin, smooth, dense yarn is obtained, and from shorter and thicker fibers - thick, fluffy and loose. The yarn production steps presented above remain the same for both fine and thick yarns. However, when spinning thin long or thick short fibers, each of the listed production stages has differences in technological processes and equipment. There are differences in processes and equipment when producing yarn of different fiber compositions.

The set of processes and machines by which the fibrous mass is processed into yarn is called a spinning system. Known spinning systems differ from each other mainly in the way they carry out two main processes: carding the fiber mass and thinning the product (Fig. 10).

Card spinning system- the most common. Carding of fibers here is carried out on carding machines. The thin layer of fibers removed from these machines is formed into a tape. The sliver is then successively thinned into roving and yarn by drawing in the drafting devices of subsequent machines. This system produces yarn with a linear density of 15-84 tex from medium-fiber cotton, as well as from chemical and short flax fibers.

Yarn spun using this system from fibers dyed in one or different colors (with the exception of linen) is called melange.

Carded yarn is quite uniform, has medium purity, but lacks smoothness.

Carded yarn is used in the production of fabrics, knitted fabrics, stitched nonwovens, some types of ribbons, braid, cords, and lace.

The comb spinning system after carding operations provides for additional combing of the fibers on combing machines. At the same time, short fibers and small debris are removed, long fibers are straightened and oriented parallel to each other. Further thinning of the resulting tape is carried out, as in the card system, by stretching on subsequent machines. This system spins yarn that is stronger, smoother, cleaner and finer. For spinning, fine-fiber cotton, flax, fine long wool, and waste from silk-winding and silk-weaving industries are used. The highest quality products are made from combed yarn. However, the use of a combed spinning system increases the cost of yarn.

Like the previous two, the hardware spinning system includes carding, but unlike the above systems there is no sliver formation.

Monofilament is a single thread that does not divide in the longitudinal direction without destruction, suitable for direct use in the production of textile materials.

Further processing of primary threads can significantly change their appearance and properties. The result is twisted and textured threads, which are called secondary.

Twisted threads consist of several primary threads folded together longitudinally and twisted into one. They have greater strength than primary threads and greater stability of other properties.

Twisted threads include twisted yarn and twisted filament threads.

Twisted yarn can be single-twist, obtained by twisting two, three or more yarns of the same length in one step, and multi-twist, obtained as a result of two or more successive twisting processes. So, to obtain double-twisted yarn, first some of the threads are twisted, and then, putting them together, they are twisted a second time.

In any of these cases you can get:

a) simple twisted yarn, when individual folded threads fed with the same tension form a homogeneous twisted thread structure along its entire length;

b) reinforced, having a core (single yarn, twisted yarn, complex threads, etc.), enveloped in different fibers (cotton, wool, flax, various chemical fibers) or threads tightly connected to the core by twisting;

c) shaped twisted yarn, consisting of a core thread, wrapped around a surge or effect thread, having a greater length than the core. The surge thread forms spirals, knots of various shapes and lengths, ring-shaped loops, etc. on the core thread. Loops, knots and other effects are fixed on the core thread by a third securing thread fed into the torsion zone at the speed of the core thread. The use of shaped twist threads makes it possible to obtain fabrics with a beautiful external effect.

Twisted filament threads, similar to twisted yarn, can be single- or multi-twist. In this case, it is possible to obtain simple complex twisted, combined and shaped threads.

According to the degree of twist, twisted threads of different degrees of twist are distinguished. Threads with weak or flat twist have up to 230 twists per 1 m of length. They are used in weaving as weft threads. Medium twist threads, or muslin, have 230-900 twists per 1 m of length and are used as warp threads in the production of fabrics. High twist threads, or crepe, have up to 2500 twists per 1 m of length. Such threads are most often produced from raw silk or chemical filament threads. Fabrics made from crepe threads have a beautiful fine-grained, matte surface, i.e. they have a crepe effect. In addition, they are more rigid and elastic, which reduces their wrinkling.

According to the direction of twist, which characterizes the direction of the turns of the twisted thread, right-hand twist threads (Z) and left-hand twist threads (S) are distinguished (Fig. 12).

The properties of twisted yarns and filament yarns are greatly influenced by the combination of the twist direction of the primary yarn and the direction of subsequent twists. The best properties are found in twisted threads in which the directions of the primary and subsequent twists do not coincide (Z/S or S/Z). During the final twist in the direction opposite to the primary one, the component threads unwind until they are secured by turns of repeated twist. Thanks to this they

form a dense thread of round shape, uniform in thickness. As a result, the twisted thread gains greater strength, and products made from it gain greater wear resistance. Textured are called threads, the appearance, structure and properties of which are changed by additional physical-mechanical, physical-chemical and other treatments. The threads have increased volume, loose structure, increased porosity and extensibility. These features are a consequence of the increased tortuosity of the elements of their structure. These include textured (high bulk) yarns and textured filament yarns.

High-volume yarn with increased elongation (30% or more) is obtained from synthetic multi-shrink staple fibers. High-shrinkage fibers, highly stretched during the manufacturing process, are shortened by steaming and, due to friction, impart a wave-like crimp to the low-shrinkage fibers, increasing the porosity, thickness and volume of the yarn.

However, textured filament yarns are more widely used in industry. There are three main methods for producing textured yarns.

The first method - thermomechanical - consists of imparting crimp to smooth complex synthetic threads by intensive twisting, fixing the twist using heat treatment, followed by unwinding. In this way, highly extensible threads are obtained. Threads obtained in this way from nylon complex threads are called elastic. The high reversible stretchability of the elastic makes it possible to produce products that should fit the human body well (socks, swimsuits, etc.). Textured threads made from polyamide filament yarns are called meron, and those made from polyester are called melan.

The second method is physical modification - imparting zigzag crimp and looseness to smooth thermoplastic filament threads by pressing (corrugating) them into special chambers followed by heat treatment. The resulting threads are classified as high-tensile threads. Textured thread obtained by corrugation is called corrugation. It is used to produce knitted fabrics for a range of outerwear, various dress and suit fabrics.

The third method is aerodynamic - imparting looseness and looseness to chemical threads of any kind by exposing them to a turbulent air flow in a loose state. This is how threads of normal extensibility are obtained. Using this method, it is possible to obtain combined and shaped textured threads from primary threads of different types. Such looped threads obtained from polyamide are called aeron. They are used for the production of high-quality dress, suit, and shirt fabrics.

Based on their fibrous composition, threads are classified into homogeneous, mixed, heterogeneous, mixed-heterogeneous and combined.

Yarn is homogeneous if it consists of fibers of the same type (cotton, flax, wool, silk, chemical fibers); complex threads consisting of elementary threads of the same type; monofilament; twisted threads (twisted cotton yarn, twisted viscose thread, etc.); textured threads (elastic from nylon thread, melan from lavsan thread).

Mixed yarn is a yarn consisting of a mixture of fibers of different origins, evenly distributed over the entire cross-section along the yarn (for example, from a mixture of cotton and lavsan fiber, wool and nylon fiber, etc.).

Twisted threads can be heterogeneous, containing homogeneous threads of different types (for example, wool yarn twisted with nylon filament thread), and mixed-heterogeneous (for example, half-woolen yarn made from a mixture of cotton and wool, twisted with nylon filament thread).

Textured threads are combined, containing different types of textured threads and ordinary chemical filament threads (for example, a combined textured tacon thread consists of a textured acetate thread twisted with a regular nylon filament thread).

In terms of finishing and coloring, textile threads can be harsh - without finishing; bleached; plain painted; sour; boiled; melange - from a mixture of colored fibers; highlighted - from two or more multi-colored fibers; shiny, matte. The finishing and coloring of textile threads depend on their fibrous composition and structure.

Security questions

1. What is yarn?

2. What is a filament thread?

3. What is monofilament?

4. What is twisted thread? What types of twisted threads do you know?

5. What is single-twist, double-twist thread?

6. How does a simple twisted thread differ from a shaped twisted thread?

7. What is reinforced twisted thread? How does it differ from plain and shaped twisted threads?

8. How do twisted threads differ in the degree of twist?

9. How do twisted threads differ in the direction of twist?

10. What is textured spun thread? What are the features of textured threads?

11. What types of textured twisted threads do you know? What are the characteristics of these threads?

12. How are different types of textured threads produced?

13. How are threads distinguished by their fibrous composition?

14. What are homogeneous, mixed, heterogeneous, combined threads?

15. What types of thread finishing do you know?

Basic properties of textile threads

The main properties characterizing textile threads include: thickness, twist, strength, elongation, unevenness.

The thickness of textile threads, as well as fibers, is characterized by linear density T (tex), which is determined by the already known formula

where m is the mass of the fiber, g; L - fiber length, km.

The linear density of a textile thread is determined by weighing a skein, i.e. a skein of yarn 100 or 50 m long, followed by recalculating the total length of the threads into kilometers and calculating the indicator using the above formula. The linear density of the thread can be calculated using the length of the thread in meters, using the formula

T = (1000t)/1,

where m is the mass of the fiber, g; / - fiber length, m.

The thickness of fabrics, knitted and non-woven fabrics depends on the thickness of the threads. The use of thinner threads makes it possible to obtain thinner fabrics and textile materials.

The twist of the threads is determined by the number of twists or turns per 1 m of thread length. This indicator is determined on a device - a torque meter. The twist of the thread depends on its thickness. The thicker the thread, the lower the number of twists per 1 m of thread length.

In order to be able to compare the degree of twist of threads of different thicknesses, an indicator has been introduced, which is called the twist coefficient b. It is calculated using the formula

where K is the number of twists per m of thread length; T-linear thread density, tex.

A low twist coefficient indicates that the thread is soft, not dense or elastic. High - because the thread is elastic, dense, thin, tough.

An increase in the number of twists leads to an increase in the strength of the thread, but increasing the strength of the thread has limits. “If you continue to twist the thread, then its strength will begin to fall. The number of twists of the thread, after which the strength of the thread begins to fall, is called critical twist .

Soft voluminous fabrics are obtained from soft threads with a gentle (small) twist. The use of high twist threads allows us to produce dry, dense, elastic fabrics.

The strength and elongation of the thread is characterized by the following indicators: breaking load and breaking elongation, which are determined when testing the skein, i.e. skein of yarn 100 or 50 m long, on a breaking machine. The force at which the skein breaks shows the breaking load in centinewtons (cN), which characterizes the strength of the threads. At the moment of rupture, the elongation at break is also recorded, measured in millimeters.

Threads with reduced strength are less processed in weaving. Their frequent breakage is observed, which leads to a decrease in the quality of the fabrics. A small elongation of the thread at break indicates the rigidity of the thread, its intractability to stretching.

The unevenness or unevenness of the thread in linear density is a significant indicator of the quality of the thread. Unevenness may result from uneven fiber length, thickness, crimp and strength. It can occur at any stage of spinning production. Unevenness in linear density is determined visually or using special devices. In the visual method, threads are wound onto screens of a contrasting color, and then the wound samples are compared with standards of varying degrees of unevenness.

The smoother the threads, the fewer deviations are observed in thickness, strength, and twist throughout their entire length.

Weaving production

Fabric is a textile fabric formed by interlacing two mutually perpendicular systems of threads on a loom. The process of creating fabric is called weaving.

The system of threads located along the fabric is called the warp, the system of threads located across the fabric is called the weft.

Fabric production is carried out in three stages:

Preparation of warp and weft;

Making fabric on a loom;

Sorting of manufactured fabrics.

At the first stage, the warp and weft threads are prepared for the weaving process. The threads received from the spinning plant are rewound into packages convenient for threading into a weaving machine.

Preparation of the warp consists of the following operations: rewinding, warping, sizing and threading of individual threads into the parts of the loom.

Rewinding of warp threads from spinning cobs or skeins onto large bobbins of cylindrical or conical shape is carried out using winding machines. In this case, packages of great length are obtained, the threads are cleaned of foreign impurities and their weak points are eliminated. Since rewinding is carried out with a certain tension of the threads, weak points are revealed by breaks. The broken ends of the threads are tied with a special weaving knot. On modern winding machines, where the rewinding speed reaches 1200 m/min, the tying of broken ends is performed automatically. The warp threads, wound on large bobbins, go to the warping.

The warping is that warp threads from a large number of bobbins (from 200 to 600 or more) are wound parallel to each other with the same tension on one large spool with flanges. Such a coil is called a warping shaft. All warp threads wound on the warping shaft must be the same length. The warping operation is carried out on a special warping machine. Warping speed - 800 m/min. The warp threads are fed from the warping shaft for sizing.

Sizing is the gluing of warp threads with a special adhesive - sizing. Sizing gives the warp threads smoothness and strength. This is extremely important in order to prevent the warp threads from breaking during the weaving process due to abrasion on the loom parts.

The size is cooked separately and then fed into the sizing machine. The size formulation includes adhesive, softening, antiseptic substances, wetting agents - substances that make the threads hygroscopic. The size recipe may vary depending on the type of fabric.

The warp threads, passing under tension through a sizing machine, are treated with sizing, pressed out, dried, separated one at a time and, located parallel and at an equal distance from each other, are wound on a shaft, which is called a weaving beam. The speed of movement of the base in the sizing machine is from 12 to 75 m/min. Weaving machines for producing fabrics for different purposes and fiber composition have different widths. Therefore, a weaving beam of appropriate width is installed on the sizing machine.

Before the weaving beam is installed on the loom, the warp is threaded and tied. Threading, or threading of the warp, is an operation in which each thread of the warp must be threaded in a certain order through the parts of the loom: lamellas, heald eyes and reed teeth.

The lamella is a thin metal plate with a round hole into which the warp thread is threaded. The lamellas serve to automatically stop the weaving machine when the warp thread breaks. The number of lamellas is equal to the number of warp threads in the warp and, accordingly, the number of threads in the warp of the fabric.

The heald frame, or heald, is located across the entire width of the loom. It consists of two horizontal strips placed one below the other. A heddle with a peephole in the middle of each heddle is vertically fixed between the slats. Warp threads are threaded through the eyes of the heddles - one through each eye. The heald frames provide the formation of a shed for laying the weft thread. The number of heald frames depends on the type of fabric weave and ranges from 2 to 32. The number of heddles corresponds to the number of warp threads in the beam, but the order of threading into the eyes of the heddles depends on the weave of the fabric.

The reed also runs the full width of the loom and consists of flat metal plates mounted vertically on two slats. The metal plates are called reed teeth. The reed serves to nail the newly laid weft thread to the previous one, as well as to maintain a uniform, parallel arrangement of the warp threads during weaving. Each warp thread is sequentially passed between the teeth of the reed.

The work of threading the warp threads into the holes of the lamellas, the eyes of the healds and between the teeth of the reed is carried out on a special parting machine. The sorting is done manually by two workers. The feeder feeds sequentially one warp thread after another, and the threader, with a special hook, pulls all the threads from the first to the last through the parts of the loom. With this organization, 1000-2000 threads are threaded per hour.

Threading is carried out when rethreading a loom to produce a new type of fabric or when replacing worn parts of a loom. If the same fabric is produced on a loom, then in this case weaving is not carried out, but the ends of the corresponding threads of the new warp from the new warp are tied (attached) to the ends of the old warp. When tying the ends of the warp, knotting machines are used with a knitting speed of 5000 knots per hour or more. To start the loom, the connected units are carefully pulled through the holes of the lamellas, the eyes of the healds, and the teeth of the reed.

There are and are used automatic machines for threading warp threads.

Preparing the weft for weaving is a simpler process, which consists of rewinding the threads onto special wooden shuttle bobbins and moistening the threads.

Rewinding on shuttle bobbins is necessary if weaving will be done on shuttle looms. This operation is performed on weft-winding machines at a speed of 300 m/min.

The threads are moistened so that when laying the weft thread from the shuttle bobbin, several turns of the thread do not unwind at the same time, which leads to the formation of defects on the fabric. Moistening of threads of different fibrous composition is carried out in different ways. Cotton and linen yarn are kept in rooms with high air humidity, wool yarn is steamed, and silk and chemical threads are emulsified.

At the second stage, fabric is produced on a loom (Fig. 13). From the weaving beam (1), the warp threads (2) go around the rock (3), pass the lamellas (4), the eyes of the healds (5) and the teeth of the reed (6). When the heald frames with heddles (5) are alternately raised and lowered, the warp threads form a shed into which the weft thread (7) is inserted. The reed (6), thanks to the rocking movement of the batt mechanism (8), when moving to the right, nails the weft thread to the edge of the fabric (9) and moves to the left position. The resulting fabric, bending around the chest (10) and the felt (11), is moved by the product regulator and wound onto the product roller (12). The warp, unwinding from the weaving beam, is thus always in a tense state.

Weaving

The formation of a fabric web occurs as a result of the mutual interweaving of two systems of threads located in two mutually perpendicular directions. The threads running along the fabric are called warp (warp), and the threads running across the fabric are called weft (weft). The sequential operations of the technological process of producing fabric are called weaving. Weaving plays a major role in the formation of the structure of fabrics, which is the second (after raw material composition) factor determining their performance properties.

The weaving process includes preparatory operations and weaving itself.

Preparatory operations. The purpose of these operations is to prepare the warp and weft threads for weaving.

Preparation of warp threads for weaving consists of rewinding, warping, sizing and threading.

Rewinding is carried out on winding machines and consists of rewinding threads from small packages (cobs, skeins) to large ones (bobbins or packages) in order to increase their length. When rewinding, the threads on the bobbin are placed with a certain tension, which increases the uniformity of their location on the weaving machine and in the fabric, and this ensures greater uniformity of its structure. When rewinding, the threads are cleared of fluff and debris, in addition, the most pronounced defects are removed.

Warping is the winding of warp threads in a certain order on a warping machine with a large number of piles onto a warping roller.

Sizing is the impregnation of warp threads with adhesive and softening substances to give them greater smoothness and increase strength, which ensures less thread breakage on the weaving machine. Starch, gelatin, synthetic substances (polyacrylamide, carboxysteelcellulose), and wood glue are used as adhesives when preparing size. The composition of the dressing for warp threads of different raw materials is not the same. Some warps made from twisted yarn, from raw silk threads and synthetic threads are not sized. The laminated warp is wound onto a weaving beam.

Threading is the process of threading (punching) the warp into the eyes of the heald heald between the teeth of the reed and into the holes of the metal plates (lamellas).

Preparing weft threads involves rewinding and moistening them. The weft threads are rewound onto forgings, the shape and size of which are convenient for the weaving process (shuttle bobbins, bobbins). In this case, the threads are cleaned of debris, some spinning defects are removed, and the winding length is increased. Weft threads are moistened, treated with steam or emulsions to give them increased elasticity, fix twist, eliminate twists, threads flying off the bobbin and reduce breakage.

Actually weaving. The structure of the fabric is formed from the warp and weft threads during the weaving process on a loom. Various types of looms are used to produce fabrics.

Automatic weaving machines, in which bobbins in the shuttle are changed automatically (or shuttles are changed), are single-shuttle and multi-shuttle, depending on the number of shuttles used. Multi-shuttle looms are used to produce fabrics with weft threads of different colors, raw materials, and structure. To produce fabrics with a more complex weaving pattern, the warp threads are distributed over a large number of heddles (10-20). The healds are lifted using a special device - carriages (carriage machines). Currently, more productive shuttleless looms are widely used in weaving.

Laying the weft thread is carried out hydraulically (a drop of water), pneumatically (a jet of air), mechanically (weft inserters) and mixed methods. The most common weaving machines are those in which the weft thread is laid mechanically (STB, rapier looms) and pneumomechanical (pneumatic rapier) methods.

To produce fabrics with complex (large) patterns, weaving looms with a special shedding mechanism called a Jacquard machine are used.

During the weaving process, the main characteristics of the fabric structure are determined depending on the threads, the type of loom and its threading parameters: the width of the fabric, the number of warp and weft threads per unit length (per 10 cm), weave pattern.

Weaving weaves

Weaving threads in fabric, the order in which the warp threads overlap each other with the weft threads is called. The pattern that is obtained on the surface of the fabric as a result of the interweaving of threads is called weaving, and the graphic representation of the interweaving of threads in the fabric is called a pattern.

The weave of the fabric consists of a continuous series of warp and weft overlaps. The overlap length is indicated by the number of threads simultaneously overlapped by the threads of the opposite system. The overlap length can be equal to one, two, three or more threads. The overlaps alternate in the fabrics in different ways, forming a corresponding weave.

A repeat weave is a completed piece of weave that, when repeated, produces a continuous pattern in the warp and weft direction. The overall repeat of the fabric weave (R) is determined by the repeat of the weave along the warp (R o) and the repeat of the weave along the weft (R y).

The shift characterizes the amount of displacement (shift) of each subsequent overlap (vertically) relative to the overlap of the previous thread. There is a vertical shift - along the warp and a horizontal shift - along the weft.

When producing fabrics, various types of weaves are used. Weaving weaves are divided into simple, or main, finely patterned, complex and large patterned.

Simple weaves. Weaves of this class (plain, twill and satin) are characterized by the number of threads in the repeat and the amount of shift. In simple weaves, the warp repeat is always equal to the weft repeat; each thread of one system is intertwined in repeat with each thread of another system only once.

Plain weave is the simplest and most common. It has the smallest amount of repeat - two threads along the warp and weft. The length of the overlap and the shift are equal to one: the overlaps are arranged in a checkerboard pattern (Figure 3.1-1). The front and back sides of the fabric have the same structure and a smooth (without pattern) surface. In this weave, the warp threads most often (one after another) overlap with the weft ones, which ensures relative rigidity of the fabric, good strength, resistance to relative shear of both warp and weft threads, and low elongation.

Fig. 3.1 Drawings of fabric weaves and their graphic representation: 1 – plain, 2 – twill, 3 – satin, 4 – satin

Twill weave has a repeat of at least three threads along the warp and weft; The warp and weft overlaps are arranged with a shift to one side by one thread (Figure 3.1-2). As a result, oblique (twill) stripes are formed on the fabric, located at a certain angle from bottom to top. The angle of inclination of the stripes depends on the ratio of the density of the warp and weft threads. The direction of shift of the floors can be from left to right or from right to left: in these cases, the direction of the stripes is different.

Satin weave is characterized by long (up to 4 threads or more) warp or weft overlaps, alternating with single overlaps of the opposite system. The magnitude of the shift of single overlaps is greater than one (by 2, 3 or more threads). Fabric repeat includes at least 5 threads (Figure 3.1-4). The density of the front threads is much greater than the purl threads. Thanks to this structure, one of the thread systems (warp or weft) creates an even, dense layer on the front side of the fabric, as a result, the front side acquires smoothness and increased shine. If the front covering is formed by warp threads, then the weave is called satin with the main covering, or satin itself. When weft threads predominate on the right side, the weave is called weft covered, or satin(Figure 3.1-3).

Finely patterned weaves. Depending on the nature of their production, they are divided into derivatives and combined ones.

Derived weaves are weaves in which the pattern of the overlaps of any main weave is preserved. They are obtained by increasing the complexity (increasing the length of the overlap) of the main weaves and are characterized by the absence of single overlaps. They are divided into derivatives of plain, twill and satin weaves.

Derivatives of plain weave are rep and checker (matting) weaves.

Rep weaves are produced by lengthening the overlaps of a plain weave in the warp or weft direction. By lengthening the floors in the direction of the base, the main (transverse) rep is obtained. Its rapport consists of 2 warp and 4 weft threads (Fig. 3.2-1). By lengthening the overlaps in the direction of the weft, a weft (longitudinal) rep is obtained (Fig. 3.2-2), the rapport of which consists of 4 warp and 2 weft threads.

The front and back sides of rep weave fabrics are the same. The fabric according to this system has a higher density and the scars are more prominent. Rep weave fabrics are characterized by good mechanical strength; they are heavier and thicker than plain weave fabrics.

Fig 3.2 Derivatives of plain weave: 1 – main rep, 2 – weft rep, 3 – types of checker weave

Checkered weaves are formed by simultaneously lengthening the main and weft overlaps (Figure 3.2-3). In this case, rectangular, often square, checkers are obtained on the surface of the fabric, the size of which is determined by the repeat of the weave, the density and thickness of the thread.

Derivatives of twill weave are obtained by increasing the length of the overlaps, the number of threads in the repeat (reinforced twill, compound twill) and changing the direction of the twill lines (broken and zigzag twill).

Reinforced twill is the simplest and most widely used derivative weave. It is characterized by longer (no single) warp and weft overlaps. If on the front side of the fabric there are more main overlaps than weft ones, the reinforced twill is called the main twill, if the weft overlaps predominate - weft, and if the number of main and weft overlaps on both sides of the fabric is the same - double-face, or equilateral (Fig. 3.3).

Figure 3.3. Reinforced twill

Complex twill (Figure 3.4) is produced by a combination of weaves of simple or reinforced twill. The compound twill weave pattern features diagonal stripes of varying widths.

Figure 3.4. A derivative of twill weave is compound twill.

Broken and zigzag twill are formed from plain, reinforced or compound twill by changing the direction of the twill lines. The result is a pattern in the form of teeth of various shapes or in the form of longitudinal stripes having different directions and offset relative to each other.

Derivatives of satin weave include reinforced satins and satins.

Reinforced satins and satins are obtained by increasing the length of the overlaps (warp or weft) (Figure 3.5). By increasing the length of the overlaps, the connection between the warp and weft threads is strengthened, and therefore the strength of the fabric. Fabrics of reinforced satin weaves have a smoother, denser surface and significant abrasion resistance.

Figure 3.5. Satin weave derivatives: 1 – reinforced satin, 2 – reinforced satin

Combined weaves are obtained by using (combining) several types of simple or derivative weaves or by constructing a new weave on their basis.

Combined finely patterned weaves are characterized by a relatively large repeat; their formation requires a large number of healds. These types of weaves are very numerous and varied in structure, repeat sizes and external effect. Ornamental weaves form a weaving pattern in the form of longitudinal and transverse stripes, cells, and various contours obtained by combining different weaves in rapport.

Crepe weaves are characterized by single and group overlaps in fabric repeat, placed in a certain order, resulting in the fabric having a grainy, uniformly rough surface. Crepe weaves can be produced in different ways: by rearranging the warp or weft threads of one or two different weaves in a specific order; superposition of one weave on another; arbitrary placement of main and weft overlaps. Crepe weaves come in warp and weft weaves.

Relief weaves - waffle and diagonal. When worked with a relief weave, a pattern is formed on the surface of the fabric with protruding warp and weft overlaps.

Translucent weaves. The peculiarity of these weaves is the formation of gaps of different sizes in certain places of the fabric, as a result of which the fabric has an openwork appearance. The fabrics of these weaves are characterized by low filling, high permeability, and lightness.

Complex weaves. Complex weave fabrics are made from three or more thread systems. They have a specific structure that cannot be obtained with the weaves discussed above. Depending on the characteristics of production, complex weaves are divided into types.

One-and-a-half and two-layer weaves. One-and-a-half-layer (two-face) weaves are formed from 3 systems of threads: from 2 warps (front and lining) and 1 weft or 1 warp and 2 wefts (front and lining).

Pique weave (piqué) is a type of two-layer weave in structure. To form it, you need 2 warps and 1 weft (simple pique) or 2 warps and 2 wefts (complex pique). When producing plain piqué fabric, the face warp is woven with a plain weave weft. The root (second) warp, located on the wrong side under great tension, is intertwined with the weft only in certain areas, depending on the pattern. Due to the high tension of the warp threads, the weft threads in the places of weaving are pulled from the front side to the back side, and indentations are formed. The combination of these indentations creates the pattern. The front surface of the fabric is produced with high density.

A complex pique differs from a simple one by an additional system of weft threads (lining weft). This increases the convexity of the pattern, as well as the thickness and density of the fabric. The patterns on pique weave fabric are very diverse - stripes, checks, various patterns. Weaving is used to produce cotton and silk pique fabrics, blankets, and bedspreads.

Pile weave fabrics are made with pile from fibers of cut threads (cut pile). Pile weaves have 3 systems of threads, with the third (additional) being a pile thread. Depending on which system forms the pile, weft-pile and warp-pile weaves are distinguished.

Looped (terry) weave of fabrics is obtained by using two warp systems (root and pile) and 1 weft. During the weaving process, the pile warp threads have low tension and, when heated, move toward the edge of the fabric along with the weft, forming loops (Figure 3.6). Therefore, the peculiarity of such fabrics is the presence of loop pile on the surface. Terry fabrics are characterized by good moisture-absorbing and heat-protective properties.

Figure 3.6. Loop weave

Leno (lace) weaves are used to produce light, low-density fabrics. When a leno weave is formed, the additional (leno) warp system with the help of special healds moves during the weaving process relative to the corresponding main warp threads. As a result of this, the leno threads wrap around the warp threads, and the weft threads secure the relative position of the leno and standing threads with each laying.

Large patterned weaves. These weaves are characterized by the formation of large patterns on the surface of the fabric due to the combination of various weaves. Large-patterned fabrics are produced on Jacquard machines; they have large repeats. To construct large-patterned weaves, all types and varieties of simple, fine-patterned and complex weaves are used. Depending on the nature of the weaves used, they are divided into simple and complex.

Simple large-pattern weaves are built on the basis of simple and small-pattern weaves, and, therefore, 1 warp and 1 weft are required to form them. These weaves are used to produce dress and lining fabrics, some types of coats, drapery fabrics, tablecloths, napkins, etc.

Complex large-patterned weaves are obtained on the basis of complex ones, so they are formed from several systems of warp and weft threads. Large-patterned weaves are one-and-a-half and two-layer, pile.

Fabric finishing

Fabrics removed from the loom are called harsh, or surye. They contain a large amount of impurities and contaminants in the form of dressing, grease (in woolen fabrics), accompanying substances (waxy, pectin, lignin), etc. Therefore, such fabrics are hard, poorly wetted, have a gray-yellow color and an unsightly appearance. In its raw form, fabrics are used relatively rarely.

To improve the appearance and other consumer properties, fabrics are subjected to complex chemical and physical-mechanical processes called fabric finishing.

The purpose of each finishing operation is to impart certain properties to the fabric and at the same time preserve the beneficial properties of the fiber from which it is made. The importance of finishing fabrics is also great because from the same raw fabric, as a result of various finishing operations, fabrics with different properties are obtained, and therefore, for different purposes.

The types of finishing operations vary depending on the raw material composition, the textile threads used, and the purpose of the fabrics. However, the entire process of finishing fabrics can be divided into several main, sequential stages: preliminary finishing, dyeing, patterned coloring, final finishing, special finishing.

Pre-finishing

The purpose of pre-finishing fabrics is to prepare them for color finishing (dying or patterned coloring) or to impart the necessary properties to fabrics produced by bleachers.

Pre-finishing is always preceded by checking the quality of raw fabrics received for finishing. At the same time, the compliance of the fabrics with the requirements of the standard is established and weaving defects and their nature are identified, which is necessary for choosing a finishing method.

Fabric dyeing

Dyeing of textile materials refers to the change in the natural color of the fiber as a result of its absorption of dyes. During the dyeing process, the fabric is dyed through and over the entire area and acquires an even, stable color; Such fabrics are called plain-dyed.

Dyes, or dyes, are colored compounds used for dyeing fibrous materials that can color the fiber. According to the chemical composition, all coloring substances (dyes) are divided into mineral and organic. Mineral dyes are few in number - ocher, red lead, ultramarine, etc.; they are used to a limited extent for dyeing textile materials (for patterned coloring).

Organic dyes have been known and used for dyeing textile materials since ancient times. Currently, instead of natural ones (indigo, alizarin, purple, cochineal, etc.), synthetic dyes are used, which are significantly superior in variety of colors and shades, intensity, and many in color strength.

Color strength depends primarily on the molecular structure of the dye. However, the concentration of the dye and the nature of its location on the fiber have a certain influence. The color fastness of various dyes in relation to each of these factors is not the same. And only a few dyes provide a color that is resistant to all influences. However, fabrics for different purposes are exposed to varying degrees to physical and chemical factors during operation. Thus, linen and lining fabrics are more exposed to the effects of friction, sweat, and moisture, while coat fabrics are subject to the effects of light and weather conditions. Therefore, the requirements for color fastness are different and are standardized taking into account the operating conditions of the fabrics.

Patterned coloring

Patterned color designs on white or plain-dyed fabric are obtained by printing (printing): dyes are applied to certain areas of the fabric according to a given pattern, which are then fixed. Printing differs from smooth dyeing in the preparation of printing inks, the choice of brands of dyes, and the methods of applying and fixing them.

For patterned coloring of textile materials, the following printing methods are used: machine, using mesh templates, airbrush, dry printing.

Machine seal. The patterned design on the fabric is produced on printing machines. The diagram of the simplest single-shaft printing machine is shown in Fig. 3.7. The fabric 2 passes between the cylinder (truck) 1 and the engraved printing roller 3. Ink is applied continuously to the printing roller using a brush 4 from trough 5. The printing roller is a copper hollow cylinder, on the surface of which a pattern is engraved. The paint is removed from the engraved surface of the printing roller by pressing a sharp steel plate against it - a squeegee 6. The counter squeegee cleans the printing roller from the sill sticking to it 7. Thanks to the pressing of the printing roller to the cylinder (truck), the paint from the in-depth engraving of the printing roller is printed on the fabric in the form of a certain pattern .

Figure 3.7. Printing machine diagram

After applying the printing ink, the fabric is dried and then, depending on the type of dye, sent for washing or curing. In the maturing medium, under the influence of temperature, humidity and the composition of the components of the printing ink, chemical processes of a reducing and oxidizing nature occur. Washing removes thickener and dye loosely attached to the surface of the fiber from printed fabrics.

In addition, there are direct raster, three-color and watercolor printing.

In raster printing, the design consists of a system of dots or line stripes of different sizes. The engraving of the printing roller in this case consists of dotted or dashed indentations, the size, depth and frequency of which determine the intensity of the dyeing of the fabric.

Three-color printing is characterized by a multicolor pattern obtained due to the mutual superposition of inks of three colors when printing.

Watercolor printing is printing on dampened fabric, as a result of which the design resembles a watercolor. With significant moisture, you can get a picture in which the edges of the elements are blurred.

The printed design can be applied on one side of the fabric (single-sided printing) or on both sides (double-sided printing).

When etching printing, thickened chemically active compounds are applied to plain-dyed fabrics, which destroy and discolor the original color in the printed areas. The result is a white pattern on a painted background (white etching). To obtain a colored pattern, dyes that are resistant to the etching reagent and are brighter than a plain-colored background are applied to the painted background along with the etching composition. In the printed areas, the dye that forms the background is destroyed, and these areas of the fabric are painted over with another dye (color etching). Etch printing is a higher quality finishing type and is used less frequently than direct printing, primarily on combed cotton and some silk fabrics. The designs produced by etched printing are not very varied.

In reserve printing, a protective composition (reserve) is applied to the pre-bleached fabric with a printing roller, after which the fabric is subjected to smooth dyeing. On areas of fabric covered with reserve, the pattern is white. A colored pattern is obtained when applied together with a reserve composition of a dye that is resistant to it. Backup printing is rarely used due to the complexity of its implementation.

Mesh pattern printing. Using this method, printed designs are applied to fabrics with a soft, movable structure (natural silk, some fabrics made from chemical fibers), which cannot be colored by machine printing due to distortions in the fabric and patterns. To apply the design, printing ink is rubbed through a mesh template. Templates for printing are a frame on which a nylon mesh is stretched. The surface of the mesh, with the exception of individual areas in the form of a specific pattern, is covered with film (varnish). Films (varnish) on the template mesh are produced using a photochemical method, which is why the designs are called photofilm printing. The fabric intended for printing is spread out, secured on the table and a mesh template is placed on it. The template frame is filled with printing ink, which is rubbed through the template mesh using a roller. The paint is applied only to the exposed areas of the fabric, resulting in a one-color design. To obtain a multi-color pattern, the number of patterns must correspond to the number of colors in the pattern. The designs of this printing method vary in size, complexity and color design.

Airbrush printing. The airbrush printing method is as follows. The fabric is fixed on a special table and templates (stencils) with cut out patterns are placed on it. The dye is applied to the fabric by airbrush by spraying. By changing the distance from the airbrush to the fabric and the duration of spraying, colors of different intensities are obtained and a gradual transition of tones is achieved. Airbrushed designs are highly artistic, with a gradual transition from dark to light tones, as well as overlay of different colors. However, the use of airbrushing is limited due to low productivity. This is how mainly piece silk items and faux fur are colored.

Dry or heat transfer printing (“sublistatic”). With this method, a pattern printed on paper with dispersed dyes is transferred using a heated calender onto wet fabric. Paper with a pattern applied to it is placed on the wetted surface of the fabric and sent to a thermal calender (heating temperature 210 ° C, processing time 30 s).

Depending on the complexity, printed designs are divided into groups: A, B, C, D and D. The first group includes simple one- or two-shaft designs, and each subsequent group contains designs of greater complexity.

Final finishing

Fabrics after bleaching, dyeing or printing are usually severely deformed. As a result of numerous mechanical influences, they are stretched at the warp and seated at the weft, the weft threads are displaced, etc. In addition, the surface of the fabric is rough and heavily wrinkled. Therefore, to restore the normal structure, give a beautiful appearance and improve some performance properties, the fabrics are subjected to final finishing. Finishing refers to a series of mechanical and physical-chemical processes that, by imparting certain specific properties to fabrics, help improve their appearance and quality. Depending on the fibrous material, type and purpose of the fabrics, the final finishing operations, as well as their quantity and sequence, are different.

Special finishes

Anti-crease and anti-shrink impregnation is carried out for cotton, linen and viscose fabrics and is a treatment during which a resin film is formed that reduces the swelling and creasing of fibers.

Permanent embossing (ST) satins, dress fabrics - applying a relief embossed pattern from film to fabric.

Silky Silver Finish (SSF) Gives fabrics made from cellulose fibers a silvery shine that is resistant to wet conditions.

All of the finishes listed above reduce the hygroscopicity, air and vapor permeability of fabrics and are unstable to repeated washing. The maximum number of washes they can withstand is 8...10.

LO finish (easy to wash) Cotton lavsan fabrics are treated with the drug emucryl.

Permanent finishing(indelible sizing) is the impregnation of fabrics with emulsions or latexes of thermoplastic resins and rubbers, followed by heat treatment, during which a thin film is formed on the fabric. The treatment gives the fabrics wrinkle resistance, elasticity, resistance to repeated washing, improves the mechanical properties, but reduces the hygienic properties of the fabrics.

Waterproof finish- obtaining film coatings on fabrics created by applying a layer of rubber, drying oils, bitumen or synthetic resins. Suitable for tarpaulins, tents and synthetic raincoat and jacket fabrics.

Water repellent finish- treatment of raincoat fabrics with water-repellent preparations containing wax, stearin, silicones, etc. The addition of aminoplasts or fluorine-containing compounds to water-repellent preparations simultaneously imparts dirt-repellent properties.

Fire retardant finish- impregnation of fabric with salts of boric, phosphoric, silicic acids, etc. Used for theater curtains, upholstery and decorative fabrics on ships and airplanes, and for workwear. After washing, the finish should be renewed.

Antimicrobial and anti-putrefactive impregnation tissue repair is performed using special and chemical preparations.

At all times, people wore clothes. Even several million years ago, our ancestors used animal skins to protect their bodies from cold, wind and rain. Gradually, the amount of materials for clothing production increased.

But, just like thousands of years ago, the main component of the process of making human wardrobe items is fabric. That is why the decision to establish your own business in the direction in question is always profitable. You just have to set your priorities correctly and take into account some important nuances.

For example, it is necessary to study in detail how to produce fabrics, what equipment is needed for this, what types of fabrics exist and other important issues. The article reveals some important aspects of this field of activity.

Homeland of fabric

Nowadays, even a small child knows that a huge number of goods enter the world market from Chinese manufacturers. However, only part of the population is aware that this Asian country is the birthplace of tea, paper, gunpowder and many other inventions that humanity still uses to this day. China is also the first country in the world to launch fabric production.

Thanks to the “domestication” of the silkworm, the population of the Celestial Empire became “pioneers” in the production of silk. The trade route connecting Asia and Europe was also named after this material. Being several thousand years ahead of other countries, China also mastered the production of cotton fabrics. Gradually, other states began to use the achievements of the Celestial Empire, and the secrets of mastery were no longer secret.

Initial stage: processing of raw materials

Today, weaving mills produce materials in every color and pattern imaginable. How is fabric produced? We will describe the process below. Many people know that fabric is made from many thousands of twisted threads. However, the first stage in the appearance of the finished material is spinning. Initially, cotton baskets, flax fibers or silkworm larvae cocoons are processed. The latter, for example, are boiled.

The processed material is placed in a container. A thin ribbon is pulled from each element. A certain number of them are twisted into a thread. This is how the spinning process was carried out a long time ago. Then it was replaced by a spindle. After that - an automatic spinning wheel. Today, fabric production is also inevitable without this process. However, all the work is done by various automated equipment.

The material collected from raw materials is subjected to loosening and scuffing. It is pressed and then divided into small portions. The next step is to remove debris and foreign impurities. The cleaned material is passed through carding machines. The surface of these devices is covered with a network of needles. The raw material passes between a rapidly rotating drum and slowly floating rollers. In this case, short and foreign fibers are removed, that is, combed out. Passing through the apparatus, the material takes the form of a thick and loose strip.

Separating and pulling fiber

The material then travels along the distribution belt to the draw frames. They, in turn, differentiate the mass into individual components and distribute them parallel to each other. Using the same equipment, the tape is pulled out.

To make the future thread stronger, the machines connect several strands together and slightly twist them. The resulting workpiece is called roving. Equipment for the production of fabrics also includes spinning machines. With their help, the roving is stretched. Then it simultaneously goes through the processes of twisting and winding onto a beam (special roller). After this, the yarn goes to the warp knitting machine, which collects the threads into separate blanks.

Warp and weft stitches

If you examine the canvas through the glass of a microscope or magnifying glass, you can clearly see the interweaving of threads. Those that run along the fabric are called warps, and those that run along the fabric are called wefts. In order for neither the first nor the second to break, and the finished fabric to be more durable, the threads are glued with a special compound called sizing. The material passes through hot rollers, which dry out any remaining sticky substance.

Production process

The warps come from the warp knitting machine to the weaving machine as a stretched fabric. In this case, the tension of the threads is such that the shuttle with the weft thread should move easily and freely between them. At an angle of ninety degrees, the weaving equipment directly produces the fabric. The automatic device makes it possible to set a mode that allows you to produce fabric with or without a pattern. This is where the threads are joined into a single fabric.

Wash and add color

Before being dyed, the fabric goes through a wash. The first process occurs in soapy water at a set temperature and continuous speed. The material is then rinsed in clean liquid. Through these steps, the adhesive substance used in weaving is washed away.

Next comes the dyeing process. The fabric is placed in clean water to which dyes have previously been added. The solution is heated and the material is soaked in it. The duration of this process reaches six hours. After this, the fabric is taken out and rinsed in warm water.

Dry and wrap

Thanks to special equipment, the material is straightened and smoothed. After this, it undergoes heat treatment. The fabric is placed in a drying chamber, where, at a set temperature, moisture evaporates from its fibers. The final stage of production is winding onto large reels. As a rule, the weight of one finished element is one and a half tons.

Looking at the right side of different fabrics, you can see that the weft thread passes through the warps at different frequencies. This allows you to create drawings (simple and complex, large and small). The first category of materials includes satin, linen or twill fabrics. Examples of the latter option are denim and wool. Linen materials include calico, chintz and others.

Denim is a rougher version of cotton material. The front side of the fabric usually has a blue tint. It is formed by warp threads. The reverse side of the material is painted white. This is the merit of the weft threads. Thanks to this combination, denim has the advantageous property of changing its color, “turning blue,” which is different from other materials. If you slightly change the structure of the twill (change the behavior of the weft shuttle), you will get a herringbone fabric. This option is widely found in the famous Wrangler jeans.

Connecting fabrics

In addition to weaving, duplication is also used in fabric production. This process involves joining two materials together using stitching or gluing. In this case, special equipment is used for duplicating fabrics - presses. As a rule, wool and synthetics, cotton and metallized material are combined together. The duplication process is used to endow the canvas with new properties: waterproofing, wrinkle-resistance, and others.

The Russian fabric market is represented by a huge number of different companies. In order to compete with them, it is necessary not only to purchase carding, knitting, weaving, winding, warping, sizing and other machines, but also to establish uninterrupted production of high-quality materials. Any project can become successful if you think through every little detail and use your hidden potential.

When designing and manufacturing a garment, it is important to choose the right materials.

Most often, textile materials are used to make clothing - threads and fabric (textiles). Their production is a complex process consisting of three stages: spinning, weaving and finishing (Fig. 9).

Rice. 9. Diagram of the fabric production process

Spinning is the process of producing a long thread (yarn) from individual short fibers by twisting them. The fibers arrive at spinning mills in the form of compressed bales. On special machines they go through several stages of processing: 1) after loosening, uniformly mixing the fibers and removing impurities from them, canvas is obtained; 2) the canvas is combed and the fibrous mass is pulled into a ribbon; 3) the fibrous mass is pulled out even more, twisted and the finished yarn (threads) are wound onto bobbins.

The main profession of the spinning industry is a spinner. It can serve a large number of spindles simultaneously. During the work process, the spinner deftly and quickly eliminates broken yarn, changes reels and bobbins, and takes care of the equipment.

Weaving is the process of producing fabric from yarn. The finished yarn enters the workshop, where it is made into fabric on weaving machines (Fig. 10).

Rice. 10. The process of making fabric on a loom: 1 - beam; 2 - warp threads; 3 - shuttle; 4 - weft threads; 5 - edge; 6 - product roller

Strong and smooth grain threads (warp) are stretched along the loom. Less strong and fluffy transverse threads (weft) are wound on the shuttle. The weft threads intertwine the warp threads in the transverse direction.

When the weaving machine is in operation, the warp threads are moved apart using a special device. A hole is formed between them, through which the weaving shuttle inserts the weft thread. When the shuttle comes back, the thread does not break. A selvage is formed along the edges of the finished fabric.

Intertwined with each other, the warp and weft threads form a weaving pattern. The most common weavings are plain, twill, satin and satin (Fig. 11).

By carefully examining weaving patterns, you can find a pattern that is repeated in all directions. A repeating weave pattern is called rapport (see Fig. 11).

Rice. 11. Weaving weaves: a - plain; b - twill; c - satin; g - satin. Selected areas - rapport

The weaving pattern of different fabrics has its own characteristics. With twill weave, each successive laying of the weft thread moves one thread to the side. This creates the appearance of oblique stripes on the fabric, more noticeable on the front side. Twill weave fabrics are slippery to the touch.

The weaving pattern of satin and satin weave is shifted by two threads in each row. The front side of these fabrics is smooth, shiny and differs sharply from the back side.

Cutting and sewing of these fabrics is hampered by their high slippage, leading to distortions and severe fraying.

The main profession of weaving is weaver. It services 48 to 64 automatic looms simultaneously. When the machine stops, the weaver eliminates thread breaks and monitors the quality of the fabric.

Fabric finishing - giving fabric a certain appearance and properties.

Fabric removed from the loom is called gray. It is ugly, hard, and does not absorb water well. Subsequently, it goes through a series of finishing processes. Here are just a few of them.

Bleaching - making fabric white. Fabric that has been bleached is called bleached.

Dyeing is the dyeing of fabric in any color using dyes. Fabric that has undergone the dyeing process is called plain dyed.

Printing - applying a design to bleached or plain-dyed fabric. This fabric is called printed.

Determining the direction of the grain thread

When cutting a garment, in order to avoid distortion of the shape of its parts and skew, it is necessary to determine and take into account the direction of the grain thread in the fabric. Here are the main signs of identifying a lobe thread in a fabric (Fig. 12):

Rice. 12. Definition of a shared thread: a - along the edge; b - by stretching; c - by appearance and strength

1. The grain thread always runs along the edge of the fabric.
2. When the fabric is stretched, the lobar threads stretch less than the transverse threads.
3. Lobar threads are smooth, thin and strong, transverse threads are thicker, fluffier and less strong.

Determining the right side of the fabric

The fabric has a front and back side. To make clothes, you need to learn to distinguish between them. Here are the main signs by which you can distinguish the front side of the fabric from the back.

1. In printed fabrics, the printed pattern on the front side is brighter.
2. On the front side there are fewer fabric defects - knots, loops, since they are specially brought out on the wrong side.
3. For twill weave fabrics, the diagonal rib on the front side goes from the lower left corner to the upper right.
4. Satin and satin weave fabrics have a smooth, shiny front side and a matte back side.

Practical work No. 6
Determining the direction of the grain thread in the fabric

You will need: two square fabric samples (with and without edge), a thick needle, a magnifying glass, chalk and a pencil.

Work order

1. On the sample with an edge, draw an arrow with chalk (pencil) indicating the direction of the grain thread.
2. Stretch the same sample first along and then across. Determine in which case the fabric stretched less and draw an arrow with chalk indicating this direction (the arrows should match). Draw a conclusion.
3. Stretch the other sample first along and then across. Determine in which direction the fabric stretched less and draw an arrow with chalk indicating that direction.
4. Using a needle, pull out the threads from the second sample: running along the arrow (thread 1) and across the arrow (thread 2). Examine these threads with a magnifying glass. Based on their appearance, determine which one is thinner and smoother (the other is thicker and fluffier). Break thread 1 and thread 2. Which one is stronger? Draw a conclusion.

Practical work No. 7
Determining the front and back sides of fabric

You will need: samples of bleached, plain-dyed and printed fabrics, a magnifying glass.

Work order

1. Select a printed fabric sample. Consider it. Which side is the picture brighter? Determine the front side.
2. Select from samples of bleached and plain-dyed fabrics. Carefully examine and compare the number of knots and fibers on each side of the fabrics. Find their front side.
3. Select from the samples a fabric that has a shiny side. Find its front side.
4. Glue the samples onto your workbook using the diagram below.

New concepts

Shuttle, warp, weft, edge; weaving pattern; spinner, weaver; plain, twill, satin, satin weave; bleaching, dyeing, printing.

Security questions

1. What is the difference between spinning and weaving?
2. How to determine the right side of the fabric?
3. Why is it important to be able to determine the direction of the grain thread in the fabric?
4. What is the difference between a printed pattern and a weaving pattern?