Varieties Of High And High Density Fabrics And Their Production Techniques.

Definition of high count and high density fabric

So-called

It means

。

According to the raw materials, as for cotton fabrics, according to the "GB/T 5325 1997 combing polyester cotton blended fabric", the yarn's linear density below 11.7 tex can be called high count (low count) yarn; high (low) is the premise of high density, the density of fabric is dense and weft density, and the density of the general yarn is thinner. The density may be greater. Therefore, high density fabrics are often based on high cost. Traditionally, high density fabrics are densely packed with 800 /10 cm and above. But the definition of high count and high density fabric should be based on the specific location.

This kind of cotton fabric gives people a fine texture, a thin hand and a lack of pparency. It belongs to the category of high-end fabrics.

In this way, the high count and high density fabric of other raw materials can also be defined according to this. For example, the high density and high density fabric of long slender silk, the material of its warp and weft yarn is less than 100 D (111.1 dtex), and the high density (low denier) high density fabric is densely packed in 800 /10 cm or above. However, according to the actual production and usage of the long and thin silk fabric, it is customary to identify the high count (low denier) high density fabric with 50 D (55.5 dtex) below, and dense fabric with 1200 /10 cm or more.

Two. Varieties and characteristics of high count and high density fabrics

At present, more and more high density and high density fabrics in the market are mainly made of bedding fabrics in household textiles, high grade shirting fabrics in dyed fabrics, and chemical fiber filament fabrics used for feather prevention.

2.1 high density and high density bedding fabric

High grade and high density fabric is the most popular material for home textiles. The raw materials of this kind of fabric are mainly low count pure cotton yarn, and polyester / cotton blended yarn and cellulose fiber such as viscose, wood or Tencel.

The warp and weft yarns of this kind of fabric are mainly single yarn, and the main yarn has 50S, 60S, 70S, 80S and so on.

When producing such fabrics, weft and warp yarns can be interwoven with different raw materials for different purposes.

Complementary functions.

Because the width of bedding fabric is wide, generally more than 220 cm, it needs to be produced by wide loom. The fabric of this kind of fabric is mostly composed of three organizations, including plain weave and satin weave.

High grade luxury bedding is designed with high density and high density fabric as the base material, followed by pattern printing and finishing. It shows the noble luxury and exquisite products, and fully embodies the trend of high value-added products.

High grade and high density bedding fabrics are also high-end products at this stage. In terms of current production technology, quality problems have been well solved.

However, there is still a problem. Because of the high demand and high density of high count and high density fabrics such as anti feather cloth, the quality requirements of raw materials are high and the yarn cost is high. At the same time, the production efficiency of extra low density and high density fabric is not high enough, which eventually leads to the high cost of production of such fabrics, resulting in the limitation of consumption scope.

2.2 top grade yarn dyed shirt fabric

Nowadays, high grade shirting fabrics are mostly high density and high density dyed fabrics. Their products are mainly low and high density pure cotton poplin, and their organizational structure is mostly plain weave, and also have Satin strips or small jacquard fabrics.

The production of such fabrics should be made of high cotton, low or super low and fine knot free yarn as raw materials, such as 50S, 60S, 70S, 80S, 100S/2, 120S/2, or even more 200S/2, so that the technical content and quality of the products can be improved.

After special finishing, this kind of fabric has the advantages of smooth handle, moisture absorption, breathability and comfortable wearing. It will undoubtedly become the first choice of high-grade shirt fabrics.

Of course, in addition to pure cotton varieties, other fiber materials are also applied in high count and high density shirt fabrics, such as hemp, viscose, Tencel, Model, cassava fiber and bamboo viscose fiber, etc. new cellulose fibers are spun into pure spinning or blending low tex yarns, and then refer to the production technology of pure cotton high count and high density poplin production, which can give full play to the characteristics of soft, moisture absorption, drapability and comfort of such fiber products.

In addition, the market also has low-grade cotton yarn and silk or Coolmax filament interwoven and other high-end shirt fabrics.

2.3 anti feather clothing fabrics

At present, the technology of silk like silk is emerging at home and abroad. The main products are low denier or ultra-low denier and high density fabric. Because of its soft handle, good capillary effect, silk like gloss, good moisture absorption, moisture dissipation and excellent hydrophobic and antifouling properties, it is widely used.

Mountaineering clothes and other clothing materials.

The raw materials of this kind of products are mainly polyester and nylon filament. The filament size is 20 D, 40 D, 50 D and so on. Its density is generally over 1200 /10 cm or even more than 1600 /10 cm, which makes it difficult to produce this kind of fabric.

In the past few years, such products produced in Japan, Korea, China, Taiwan and other countries and regions have attracted the attention of the Chinese people for their excellent internal performance and gorgeous appearance, as well as the moderate price and excellent wearability of the products.

The development of products.

In recent years, China's vast number of chemical fiber filament fabric production enterprises have made great progress in the production technology of low denier or ultra-low denier high density fabrics through the one-stop technical tackling of raw materials, weaving, dyeing, finishing and equipment, and basically realized the "substitution import" of such fabrics.

Three. Production technology of high count and high density fabric

Production difficulties analysis of 3.1 high count and high density fabric

Because high count and high density fabric is commonly found in fine yarns (or low denier), high density of longitude and weft, total number of roots, many interweaves and dense cloth, there are often phenomena such as unclear opening, disorderly yarn, fuzzing and broken yarn in weaving process, resulting in serious "three hop" defects. Therefore, when producing high count and high density fabric, we should take full account of the quality of raw materials, semi-finished products processing technology and quality control, and weaving machine optimization design.

The following is a description of the production technology of 3 typical high density and high density fabric.

Production of 3.2 high density and high density bedding fabrics

The production of high count and high density bedding fabric is usually made of raw yarn and then finished by dyeing or printing.

Because of the fine yarn density, longitude and latitude density, the total tightness is over 80%, and the width of the fabric is wider, it is advisable to use wide air-jet looms to produce weaving production.

Because the high count and high density fabric of cellulose fiber has the characteristics of good hygroscopicity, low shrinkage and strong silk quality, it is suitable for high-grade home textile bed fabric.

7.3 tex x 7.3 tex 551 x 551 /10 cm 267 cm 1/1 Tencel flat weave organization is taken as an example to introduce the production technology of this kind of fabric.

It has the characteristics of "small opening, fast weft insertion, big tension and strong beating".

For this reason, on the one hand, the high quality compact spinning yarn must be selected for high speed weaving of air-jet looms, especially for yarn evenness, high strength, elongation at break, small CV strength and hairiness, so as to ensure stable production.

On the other hand, air-jet looms are high density fabrics woven by strong beating, but the density is not unlimited. The beating resistance coefficient and fabric coverage factor are the first parameters to determine the varieties.

In practical application, weaving difficulty coefficient K= can be used.

It is decided that the K value within a general width of 190 cm should not exceed 34. For the case with a width of less than 280 cm, the K value of bedding fabric should not exceed 32, otherwise weaving will be very difficult.

The wide width, high count and high density bedding fabric is also very demanding on the quality of pre weaving technology and semi finished products.

When winding, it requires less yarn defects, better shape and less hairiness. As far as possible, there is no knot, so it is advisable to use automatic winder, such as AC338 automatic winding machine.

The process principle of "low speed, light tension, small elongation and elastic force" is adopted in production, and reasonable technological parameters and yarn cleaning range are worked out.

Its yarn 100 thousand M harmful yarn defects should be controlled within 8, suitable for air splicing, the strength of its joint should reach more than 85% of the original yarn strength, so as to meet the requirements of warping and cheese feeding.

During the warping, the tension is uniform, uniform, uniform and broken.

The speed of the warping locomotive must be reasonably chosen, and its technological configuration should be strictly determined according to the requirements of varieties, so as to avoid shutting the car off without any reason, so that the broken ends of the warping can be controlled within 3 /10 m.

The quality of sizing directly affects the production efficiency and quality of wide width, high count and high density bedding fabrics. Therefore, it is required that the sizing is smooth and round, the rate of reinforcement is high, the hairiness is stickers, the coating is complete, the elasticity and wear resistance are good, so as to improve the weaving ability of the weaving shaft.

First of all, it is reasonable choice of sizing formula, followed by rational sizing route.

When designing, it depends on the varieties and sizing machines.

For example, the warp used in the above example is pure Tencel super fine count compact yarn. The total number of the warp yarns is too many. The friction between warp yarns is serious during weaving. At the same time, due to the tight arrangement of fibers in the compact spinning body, the slurry is not easy to penetrate into the yarn body when sizing, resulting in the phenomenon that surface sizing and film adhesion are not firm.

In addition, high speed jet weaving has the characteristics of "small opening, big tension and strong beating". It requires that the warp can withstand more repeated stretching, friction and good clearness of the shed. Therefore, "double groove, small tension, low viscosity, high pressure, heavy penetration and high pulp rate" should be adopted for sizing such fine count compact spinning yarns, so as to improve the abrasion resistance and hairiness of sizing, and reduce the elastic loss of sizing as far as possible.

It is suitable to adopt advanced and wide air-jet looms for weaving production. According to the characteristics of the varieties and the requirements of the cloth style, it is appropriate to adopt the technological configuration of "small double-layer shed, short shuttle mouth length and big tension".

The use of a small double-layer shed is conducive to the delamination of the front shed yarn and reducing the friction between the ends.

However, the small double-layer shed is easy to cause unclear opening. Large tension must be adopted to ensure that the shed is clear when weft insertion.

However, when the tension is increased, the stopping rate of broken weft will increase, and the probability of weaving defects such as starting gear, thin road and wavy mark will increase.

For this reason, the position line should be adjusted reasonably to move the back beam and the stop frame forward to shorten the length of the front shed so as to reduce the pverse movement between the warp and the friction between the heald and warp yarn, so that the front weaving is forced to clear, thereby reducing the number of weft stops, improving the weaving efficiency and reducing the weaving defect rate.

Production of 3.3 high count and high density shirt fabric

Pure cotton high count and high density poplin has the advantages of comfortable and soft feel, breathable and breathable, full grain appearance and strong sense of three-dimensional shape. It also has the disadvantages of easy wrinkle and poor shape. But it can be used to weave pure cotton high count and high density poplin through compact spinning line, and then through liquid atmosphere finishing and moisture crosslinking finishing. This can ensure the original advantages of cotton fabric, and can also modify and optimize cotton fiber, improve the gloss of finished products, improve its handle and elasticity, completely meet the requirements of ironing, improve the quality and grade of products, and undoubtedly become the first choice of high-grade linen fabrics.

The main production technology of C9.7 tex x C9.7 tex 551 x 472148 pure cotton dyed poplin is introduced.

In fact, the key production technology of high count and high density yarn dyed shirting fabrics is mainly reflected in these aspects: (1) yarn bleaching and dyeing process; (2) pre weaving preparation and flower arranging process; (3) reasonable weaving technology; (4) proper and proper finishing process.

Yarn bleaching and dyeing is a key process in yarn dyed fabric production, and its quality directly affects the production of all processes in the back track.

After dyeing and dyeing, the mechanical and physical properties of yarns will change. As the warp yarn is C9.7 tex, the yarn is fine and the yarn is tight. Therefore, it is advisable to use high temperature and high pressure cylinder dyeing process.

When the yarn is dyed by cylinder, its capillary effect is about 10 cm, and the coefficient of strength is not less than 0.90. At the same time, it is necessary to reduce the chromatic aberration as far as possible and avoid the deterioration of the yarn quality index.

This requires reasonable design of the loose cylinder, dyeing and tight cylinder according to the specific varieties.

In order to improve the winding quality of the yarn, it is necessary to adjust the winding speed, ensure the quality of the knot and design the winding density properly, so as to ensure the shape of the cheese.

The key point of warping is to ensure that the tension, arrangement and winding of the yarn are three evenly distributed.

In the warping production, taking into account the fine yarn number, the warping speed should be adjusted properly, the warping tension should be grasps and the tension of the side yarns should be increased, so as to achieve uniform layout of the yarn and reduce the broken ends, so as to provide a strong guarantee for the later production.

Sizing is a key process in weaving production. According to the characteristics of the yarn size, density and total number of warp, the advanced double sizing machine is suitable for specific warp arrangement.

The sizing process of "double penetration", "double penetration and double pressure" for "penetration, middle coating, bullets and high moisture regain" is adopted in sizing.

As the warp is C9.7 tex compact spinning, taking into account the cost, environmental protection and sizing effect and other factors, as far as possible the use of modified starch and acrylic acid and other sizes, less or no PVA.

At the same time, according to the arrangement of warp color and the characteristics of colored yarns, it is advisable to adopt suitable process of arranging flowers and flowers, so as to ensure the accurate shape of the slurry axes, so as to reduce the appearance of head twisting, head pulling and flower walking during weaving.

When weaving, high performance rapier looms or air-jet looms can be selected. For example, if the weft number is less than 4, the air-jet loom is recommended, because jet looms can achieve high speed, high yield and high quality. When the color latitudes reach more than 4 colors or there are Satin strips or small jacquard looms in the organization, the rapier loom is suitable.

In view of the characteristics of high count and high density dyed poplin, such as fine yarn density, high density and multiple pages, weaving technology should be adjusted reasonably when weaving production. Weaving process adopts the principle of "big tension, middle speed, small shuttle mouth, late opening and low back beam", which is beneficial to opening the clear shed, ensuring weaving efficiency and reducing fabric defect rate, and is conducive to forming full effect of cloth grain.

When using rapier weaving machine weaving, the weft insertion parameters should be taken into consideration, such as the time of entering the sword, the time to withdraw the sword, and the time of the two swords pfer, etc., which should be matched with the opening time and beating time. When weaving by air jet weaving, the weft insertion parameters should be taken into consideration, such as the main and auxiliary nozzle feed time and the air supply pressure, and the parameters of the auxiliary nozzle group and the gas supply time.

In addition, the production environment needed to weave the fabric should be guaranteed, so as to improve the production efficiency and product quality of looms.

3.4 production of ultra-low denier high density chemical fiber anti feather fabric

Low denier or ultra-low denier high density chemical fiber fabrics are prone to appear in the process of weaving. Serious breakage will result in a lot of warping, resulting in low efficiency of looms and poor quality of products.

The main reason for this situation is that the raw materials used are fine denier or ultra-low denier chemical filament yarn, which has poor cluster quality, low monofilament strength, high warp and weft density, and high speed of looms. Thus, the number of times of friction and stretch in such weaving process is obviously greater than that of conventional varieties.

For this kind of fabric production, whether the water jet loom or air-jet loom is used to weave, the preparation process and quality of pre weaving are particularly important. The pre weaving production usually needs warping, uniaxial sizing, parallel spindle and sub division.

The following 20 D 20 D 782 * 646155 fine denier high density polyamide fabric is introduced as an example to introduce its main production technology.

In order to make sure that the raw silk is on the rack, it is necessary to check whether there is any wool or not. At the same time, we should pay attention to the batch number, specification and length of the raw materials. During the warping process, we should ensure that the tension of each warp yarn is uniform. When the warps are wound, the friction and tension of the warp wire should be reduced as far as possible, so as to avoid damage to its strong force and elasticity. When handling the broken ends, we should pay attention to crossing the yarn without crossing the other wire paths, causing the twist to pass through, and the knot should be small and firm. If the broken wire head has been involved in the warp shaft, it can not reverse the connection, it needs to put paper strips, record the number of codes, facilitate the broken processing of the thread, facilitate the adjustment of the take-up tension and warping speed at any time, so as to ensure that the process of the whole warp shaft is kept reasonable during the processing. Warping time

When sizing, it is important to control slurry selection, slurry concentration, sizing rate, drying temperature and coiling tension.

Generally speaking, water jet weaving should select "sizing technology at low temperature, high pressure, high speed and heavy penetration", so as to achieve the surface hairiness of the warp surface and enhance the cohesion of the tow, thereby greatly improving its wear resistance.

However, due to the dry weather in autumn, the breaking rate of warp silk will increase, and the sizing rate will not be greatly helpful to weaving. At this time, the amount of oil should be increased.

At the same time, the upper axle should pay attention to the left and right rear to confirm the order of the warp axis. At the same time, the bottom of the weaving shaft must be covered with thick cardboard to avoid the occurrence of wool. When the yarn breaks more than 5 bar, the shaft must be disposed. If the slurry is spotted, the shaft must be dropped, so that the spot will be rolled on the bottom of the weaving shaft.

The key points of co axial control are mainly the number of parallel axes and the delivery tension of each shaft, and the coiling tension is uniform.

According to the characteristics of the varieties and the relevant operating rules, the number, type, speed and error rate of the needle should be selected correctly.

Make sure that the warp yarn is divided into upper and lower two layers in odd even order, so as to facilitate the operation of the warp.

Slow down the frictional impact force of the opening and beating movement on the warp threads; reasonably adjust the position of the rear beam, the working length of the tension spring and the weight of the weight of the heavy hammer, so as to reduce the tension on the warp threads; reduce the opening movement of the warp threads appropriately, reduce the change of warp tension during the opening process; at the same time, rationally adjust the weft insertion parameters such as water line, water volume, hydraulic pressure and ejection time; and timely detect and correctly handle the broken warp, especially when the machine is broken (i.e. the heald frame to the rear beam), the arrangement of the warps must be straightened out so as to avoid the interlocking and winding between the warp threads and the warp threads, so as to improve the running efficiency of the loom and improve the quality of the products. In view of the characteristics of raw materials and products, we should use plastic heald wire instead of traditional metal heald to reduce the abrasion and static electricity of the filament and reduce the speed of loom.

Four, conclusion

There are many kinds of high density and high density fabrics, and their uses are more and more extensive. Here, only some typical representative varieties are introduced and their production techniques are introduced, which is obviously not comprehensive enough.

High count and high density fabric is one of the high-grade fabrics. Because of its difficulty in production, it is much higher than the added value of the conventional products. Therefore, in response to the state's need to accelerate the supply side reform strategy, the majority of textile enterprises should intensify their technological innovation and product upgrading, actively develop more types of high density and high density fabrics, and develop them in a characteristic and serialized way, so as to meet the needs of consumers for high-grade textiles and achieve good economic and social benefits for enterprises.