KR910006427B1 - Non woven fabric and the production thereof - Google Patents

Abstract

None.

Description

Central fabric and manufacturing method thereof

Comparative chart comparing the strip tensile strength of the nonwoven fabric of the present invention and the nonwoven fabric of the prior art.

It relates to a heavy-weight nonwoven fabric produced by stapling staple fibers of the synthetic organic polymer of the present invention with hydraulic pressure. In particular, the present invention relates to a nonwoven fabric having strong tensile properties and high resistance to tearing.

Nonwoven fabrics produced by hydraulically interlacing staple fibers of synthetic organic polymers without the use of resin binders to melt-bond fibers and fibers are known in the art. These nonwovens are usually 4 oz / yd²It has been produced commercially with a unit weight of [136 g / m 2] or less. US Pat. Nos. 3,493,462, 3,508,308 and 3,560,326 to Bunting et al. Have a unit weight of about 20 oz / yd.²Various nonwoven fabrics of [680 g / m 2 or more] are described. A seamless nonwoven fabric, typically made by hydraulically entangled staple fibers, is strong and 8.5 (lb / in) / (oz / yd²) The above strip tensile strength is shown. However, this type of heavy nonwoven fabric described in bunting and the like is relatively weak. For example, the tensile strength of such a woven fabric would be 6.7 oz / yd²4.39 (lb / in) / oz / yd for [227g / m²]²[0.226 (N / cm) / (g / m 2)] and the weight is 10 oz / yd²1.3 (lb / in) / (oz / yd for [339g / m²]²) [0.067 (N / cm) / g / m2)] and weighs 20 oz / yd²1.1 (lb / in) / (oz / yd for [678g / m²]²) [0.059 (N / cm) / g / m 2].

Various attempts have been made to strengthen nonwoven fabrics produced by entangled staple fibers with hydraulic pressure. This approach involves mixing long fibers (eg, 6 in [15.24 cm] in length), fibers with a special cut, substantially continuous filament yarn, scrim, continuous filament web layers, or specially designed layers in the nonwoven fabric. It includes a method to make. Process variations intended to enhance the strength of nonwovens include a method of treating staple fibers moving in one direction in the form of a web with a hydraulic jet, and then treating the web moving in a direction perpendicular to the initial direction with a hydraulic jet; Adding special chemicals to hydraulic jets; There are a method of using a special support or grill in a web treated with hydraulic pressure and a method of starting using a special yarn. In general, each of these strains of increasing strength is useful for lighter weight nonwovens, but in general, such strains produce a strong, tight, nonwoven fabric consisting essentially of staple fibers of synthetic organic polymers that are hydraulically entangled. Not happy to do it. Such strong intermediate fabrics are suitable for applications such as strong gas filtration. It is an object of the present invention to provide a strong, flawless middle woven fabric.

The present invention provides a tight, improved hollow woven fabric made by hydraulically entangled staple fibers of a synthetic organic polymer. Improvements range from unit weights of 200 to 850 g / m 2 [6 to 25 oz / yd ² ], grab strength of at least 160 N / cm [91 lb / in], and strip tensile strength of at least 0.26 (N / cm) / ( g / m 2) [5 (lb / in) / (oz / yd ² )] and a nonwoven fabric having a tear resistance of at least 50 alternating elongation cycles. Preferably, the nonwoven fabric has a unit weight in the range of 240 to 500 g / m 2 [7 to 15 oz / yd ² ], grab strength in the range of 245 to 875 N / cm [140 to 510 lb / in], and strip tensile strength. 0.36 to 0.77 (N / cm) / (g / m 2) [7 to 15 (lb / in) / (oz / yd ² )], and the tear resistance is at least 90 alternating extension cycles. Typically, the jet track of a preferred nonwoven is 3 to 10 / cm [7.5 to 25 / in]. Preferred staple fibers are fibers having a fineness of 1 to 18 dtex [0.9 to 16 denier] and a length of 0.6 to 5 cm [1/4 to 2 inches]. Preferred polymers for staple fibers are poly (p-phenylene terephthalamide), poly (m-phenylene isophthalamide) or poly (ethylene terephthalate).

In addition, the present invention supports a bat made of staple fibers of a synthetic organic polymer on a pore screen, and moves the bat vertically with respect to the heat of the water stream, The present invention provides a novel process for producing a seamless mid-woven fabric by treating it with different water streams. The method of the present invention for producing stronger nonwovens consists essentially of staple fibers having a length in the range of 0.6 to 5 cm and a fineness in the range of 1 to 18 dtex, and the nonwovens from batts having a unit weight of 200 to 850 g / m 2. This bit is precompressed and wetted with a stream of water applied to a portion of the staple fibers from the surface of the batt through the bat to the opposite surface of the bat, the heat of the stream being in the range of 3 to 10 / cm. Are spaced apart and supplied from an orifice in the range of 0.13 to 0.22 mm in diameter. In a preferred embodiment of the present production method, the bat unit weight is in the range of 240 to 510 g / m 2, the fiber length is in the range of 1.3 to 3.8 cm, the fineness is in the range of 1.4 to 2.5 dtex, and the orifice frequency is 3 to 6 / It is in the range of cm and the water flow is supplied at a pressure in the range of 6,890 to 22,740 kpa.

The present invention can be more easily understood with reference to the drawing, which is a graph of strip tensile strength against unit weight, which compares the nonwoven fabric of the prior art with the nonwoven fabric of the present invention.

As used herein, the term “nonwoven fabric” refers to a seamless nonwoven fabric of staple fibers entangled by hydraulic pressure with a unit weight in the range of 200 to 850 g / m 2 [6 to 25 oz / yd ² ].

The main properties of the products of the invention are illustrated in the graphs of the accompanying drawings. The hatched portion represents a seamless nonwoven fabric of staple fibers entangled with prior hydraulic pressure. Each point shown in the graph represents strip tensile strength data described in detail in the Examples described later. The tensile strength of the middle woven fabric of the present invention is much higher. Such strong nonwovens of the present invention also have excellent grab strength and tear resistance.

In general, the fineness of staple fibers suitable for use in the seamless nonwoven fabric of the present invention is in the range of 1 to 18 dtex [0.9 to 16 denier] and the length is in the range of 0.6 to 5 cm [1/4 to 2 inches]. Preferably, the fineness is in the range of 1.4 to 2.5 dtex [1.25 to 2.25 denier] and the length is in the range of 1.3 to 3.8 cm [1/2 to 1½ in]. Fibers with a circular cross section are preferred.

Staple fibers can be synthetic organic polymers. Preferred polymers include poly (p-phenylene terephthalamide), poly (m-phenylene isophthalamide) and poly (ethylene terephthalate). Nonwovens made from hydraulically entangled fibers of each polymer are illustrated in the examples.

The seamless mid-woven fabric of the present invention has a combination of unique and advantageous properties, and its grab strength is at least 160 N / cm [91 lb / in], preferably in the range of 245 to 875 N / cm [140 to 500 ld / in]. And the strip tensile strength is at least 0.26 (N / cm) / (g / m 2) [5 lb / in) / (oz / yd ² )], preferably 0.36 to 0.77 (N / cm) / (g / m 2) ) [7 to 15 (1b / in) / (oz / yd ² )], and the tear resistance is at least 50 alternating extension cycles, preferably at least 90 cycles.

In the production of the preferred nonwoven fabric of the present invention, the nonwoven fabric produced by the preferred method of performing entanglement by hydraulic pressure has a repeating pattern of closely spaced fiber entangled so-called jet tracks. This jet track can be easily seen with a low magnifier. Preferred nonwovens of the present invention have 3 to 7 jet tracks [7.5 to 2.5 / in] per cm, most preferably 3 to 6 jet tracks [7.5 to 15 / in] per cm.

Known techniques using Radno-Webbers or air-integrating devices as described in zafiroglu, US Pat. Furnace staple fibers are formed with a starting batt of 200-850 g / m 2 [6-25 oz / yd ² ]. The starting batt formed of staple fibers is then subjected to continuous hydraulic entanglement on a pore support such as a nonwoven wire screen.

In hydraulic entanglement, the bat is exposed to a series of fine columnar water flow, which is provided on one side of the bat, followed by the other side of the bat. Water flows from an orifice row about 2.5 cm [1 in.] Above a short distance surface. Orifices of the type described in Dworjanyn, US Pat. No. 3,403,862 are used. Preferred orifice diameters range from 0.13 to 0.22 mm [0.005 to 0.009 in]. In a preferred method of the invention the orifices are spaced such that the jet tracks are produced at least 3 / cm [7.5 / in], at most 10 / cm [25 / in], most preferably at most 51 cm [12.7 / in].

In a preferred hydrotreatment, a portion of the staple fibers initially located on one side of the bat are penetrated by the water jet to the opposite surface of the bat. Significant rearrangements of the fibers are performed immediately after wetting the bat first, weakly precompressing it. If the adhesion of the starting mat is sufficient when supplying the bat to the entanglement stage, if sufficient pressure is applied to impact the bat with sufficient force, the first row of water streams can perform a significant rearrangement. A wider spacing jet (i.e. 10 / cm or less) allows less water to penetrate the adjacent water stream and penetrates the water deeper into the bat than can be penetrated by closer spaced jets. It is also desirable to have the highest pressure supplied to the first row of jets (or the first row after the first wet operation) as compared to the conventional practice of gradually increasing the supply pressure of the water flow in each successive jet row. Preferably, the pressure for the first row of such jets is in the range of 6,890 kpa to 22,740 kpa [1,000 to 3,300 psi]. This pressure prevents the fiber from forming a tightly entangled surface layer at the batt's surface, which prevents water flow from penetrating the batt and part of the fiber from penetrating from one surface of the bat to the opposite surface. do. Once the desired rearrangement has been carried out, subsequent entanglement can be carried out by known methods. Using closer spaced jets in the remainder of the hydraulic entanglement process, the jet tracks caused by the jets with high initial impact are not lost or apparent. It is believed that the preferred hydro-jet treatments described in comparison with the other methods exemplified herein can produce heavy woven fabrics that are more strongly and better entangled and have greater peel resistance.

Staple blend fibers of various lengths and / or finenesses can be more easily manufactured with the nonwoven fabric of the present invention than fibers having constant lengths and fineness. Therefore, the staple blend fiber can be formed into a nonwoven fabric by reducing the total energy cost per unit weight of the nonwoven fabric, the total energy impact applied to the product is small, and lowering the maximum pressure of the jet. Heavier, longer, and stiffer fibers are more difficult to rearrange and entangle.

The following test steps are used to measure the various features and characteristics reported herein. All measurements are made on dry nonwoven fabrics or fibers.

Tensile properties are measured using an Instron tester at a temperature of 70 ° F. and a relative humidity of 65%.

The tensile strength of strip is 1/2 in. [1.27cm] in width and 4 in. [10.16cm] in length with gauge length of 2in [5.08cm] and elongation rate of 50% / min according to ASTM method D-828-60. Measure with a sample.

Grab strength is 4 in. [10.16 cm] wide and 6 in. [15.24 cm] long with a gauge length of 3 in. [7.62 cm] and elongation rate of 25% / min in accordance with the general ASTM method D-1682-64. Measure with

To measure each tensile strength, the samples are cut in the machine direction (MD) and the cross-machine direction (XD) of the nonwoven fabric. Only the mean values of MD and XD are plotted on the graph of the accompanying drawings.

The tear resistance of a seamless nonwoven fabric is measured periodically by the alternating elongation technique described in Jones & Auspos. [Note: The measurement of the Resistance to Disentanglement of Spunlaced Fabrics' '(Nonwoven Technology ... Its Impact On the 80', INDA, New Orleans, Louisiana, 158-162, 1979, 3). The load (g) applied to the test sample in the machine direction of the fabric (ie, perpendicular to the testing machine) is unit weight (g / m 2) x 2.95. The load applied in the cross-machine direction is 1/2 of the load applied in the machine direction.

In the embodiment where the staple fibers are batted, a hydrojet treatment is performed to form a strong, heavy nonwoven fabric of the present invention. Different sets of orifices are used to provide / circumferential flow of water to the bat while supporting the bat on the screen under the provided device to remove water. The orifices are arranged in a vertical row with respect to the direction in which the bat moves and are positioned about 1 inch (2.5 cm) from the bat's surface. Five sets of orifices and five different screens are used. These orifice sets are as described below:

In orifice sets A, B, C, and E, all orifices are in line, but in set D the orifices are arranged in two staggered rows of 0.04 iN [0.10 cm] apart, each row having 20 orifices / in [7.9] / Cm].

The different wire mesh support screens used in the examples are as described below:

Example 1

This example illustrates the present invention using a seamless, jet-tracked, heavy-duty fabric produced by hydraulically entangled staple fibers of poly (p-phenylene terephthalamide). The tensile properties of the nonwoven fabric are remarkable.

아라미드 섬유로부터 란도-웨버 공기집적기 위에 형성된 3층의 웹으로 이루어진다. 섬유는 이 아이 듀퐁 드 네모아 앤드 컴퍼니(E. I. Du Pont de Nemours and Company) 사로부터 시판된다. 배트 1-a의 중량은 14.7 oz/yd²[498g/㎡]이고 배트 1-b의 중량은 16.4 oz/yd²[556g/㎡]이다. 각각의 배트를 스크린 C 위에 놓은 다음 오리피스 셋트 C 에 공급되는 원주상 수 제트열 아래로 10 yd/min[9.14m/min]의 속도로 통과시킨다. 연속적으로 제트열에 대한 공급압력은 제1의 제트열에 대하여 500psi[3,450kpa]이고, 그 다음의 제트열 3개에 대하여 각각 3,300psi[22,740kpa]이다. 이어서 배트의 반대편 표면에도 동일한 제트처리를 연속적으로 행한다.Two batts of poly (p-phenylene terephthalamide) staple fibers are prepared. Each bat is 3/4 in [1.9 cm] long and has a fineness of 1.5 denier [1.7 dtex] T-29Kevlar

It consists of three layers of webs formed on the Lando-Weber air accumulator from aramid fibers. The fiber is commercially available from EI Du Pont de Nemours and Company. Bat 1-a weighs 14.7 oz / yd ² [498 g / m 2] and bat 1-b weighs 16.4 oz / yd ² [556 g / m 2]. Each bat is placed on screen C and then passed at a rate of 10 yd / min [9.14 m / min] below the columnar jet of water supplied to orifice set C. Continuously the supply pressure for the jet train is 500 psi [3,450 kpa] for the first jet train and 3,300 psi [22,740 kpa] for the three subsequent jet trains, respectively. Subsequently, the same jet treatment is continuously performed on the opposite surface of the bat.

Table 1 lists the total energy and total energy-impact product (Ex I) consumed during the hydrojet treatment, depending on the characteristics of the seamless nonwoven fabric produced. The average values of the MD and XD strip tensile strengths of the nonwoven fabrics are plotted in the figure, and it can be seen that the strip tensile strength of the subwoven fabric of the present invention is surprisingly higher than the highest strip tensile strength indicated by the same nonwoven fabric of the preceding weight. The strip tensile strength of the nonwovens described in this example is about 7.7 to 9.2 times the strip tensile strength of the preceding comparable weight nonwovens.

TABLE 1

* Footnotes: 1. The unit of strip tensile strength is (1b / in) / (oz / yd ² ).

2. The unit of strip tensile strength in parentheses is (N / cm) / (g / m²).

Example 2

This example illustrates the present invention using a tight, jettracked, nonwoven fabric produced by hydraulically intertwining staple fibers of poly (m-phenylene isophthalamide).

) 아라미드 스테이플 섬유의 배트 2개를 제조한다. 노멕스 섬유는 이 아이 듀퐁 드 네모아 앤드 컴퍼니사에 의해 시판되며 폴리(m-페닐렌 이소프탈아미드)중합체로부터 제조된다. 배트 2-a는 필수적으로 점도가 2데니어[2.2dtex]로 동일하지만 길이가 각각 1.5in[3.8㎝] 및 1/4in[0.64㎝]인 스테이플 섬유의 67/33의 혼합물로 이루어진다. 배트 2-b는 필수적으로 1in[2.5㎝]이고 섬도가 2데니어[2.2dtex]인 스테이플 섬유로 이루어진다. 배트 2a와 2b를 원주상 수압제트로 처리하여 중량이 각각 7.0 oz/yd₂[237g/m₂] 및 8.6 oz/yd₂[292g/m₂]인 부직포를 형성시킨다. 표2에 연속적인 제트처리를 요약한다. 5개의 제1제트열은 배트의 한쪽 면에 충격을 가하고, 나머지 열은 다른 면에 충격을 가한다.Nomox is an air-integrated method of the type described in US Patent No. 3,797,074 to Zafirroglu.

) Two bats of aramid staple fibers are made. Nomex fibers are commercially available from I. DuPont de Nemo and Company, and are made from poly (m-phenylene isophthalamide) polymers. Bat 2-a consists essentially of a mixture of 67/33 of staple fibers having the same viscosity of 2 denier [2.2 dtex] but 1.5 in [3.8 cm] and 1/4 in [0.64 cm] long, respectively. Bat 2-b consists essentially of staple fibers of 1 inch [2.5 cm] and fineness of 2 denier [2.2 dtex]. By treating the batt 2a and 2b in a cylindrical pressure jet to form a nonwoven fabric of a weight of each _{7.0 oz / yd 2 [237g /} m 2] and _{8.6 oz / yd 2 [292g /} m 2]. Table 2 summarizes the continuous jet treatment. The first five rows of jets impact one side of the bat and the remaining rows impact the other side.

TABLE 2

The energy required for the treatment of bats 2-a and 2-b and the total Exl product are summarized in Table 3 according to the properties of the resulting nonwovens. The average strip tensile strength of the bat is plotted in the figure and it can be seen that the strength advantage of the nonwoven fabric of this example is similar to the preceding nonwoven fabric of the same weight.

TABLE 3

* Footnotes: 1. The unit of strip tensile strength is (1b / in) (oz / yd ² ).

2. The unit of strip tensile strength in brackets is (N / cm) / (g / m²).

Example 3

This example illustrates the preparation of the nonwoven fabric of the present invention from poly (ethylene terephthalate) staple fibers having a fineness of 1.35 denier [1.5 dtex] and 3/4 in. [1.9 cm] in length. This nonwoven fabric exhibits excellent tensile properties and resistance to tearing. Four nonwovens are produced as described below.

Bat 3-a is prepared on a Lando-Weber apparatus and then treated continuously with a hydraulic jet from orifice set C, feeding at a rate of 10 yd / min [9.14 m / min] on screen support C. The bat is treated with seven jet rows. The first four jets process one side of the bat and the other three jets process the other side of the bat. The jet feed pressure is 200 psi [1,380 kpa] for the first jet train and 2,800 psi [19,290 kpa] for the remaining jet train.

Bat 3-b is formed with an air-integrating device of the type described in US Pat. No. 3,797,074 to Japiroglu, and then processed continuously with seven jet trains at a rate of 10yd / min [9.14 m / min]. do. The first four jets process one side of the bat, and the other three jet rows process the other side of the bat. Under the first jet row, the bat is on the support screen c; On screen A under the next three jet trains; Under the last three jet trains, they are on screen B. The first jet train is supplied through orifice set C at a pressure of 1,000 psi [6,890 kpa]. The next three rows are fed through orifice set D at pressures of 500, 1,500, and 2,000 psi [3,450, 10,340 and 13,780 kpa], respectively. The final row is fed through orifice set D at pressures of 500, 1,500 and 2,000 psi [3,450, 10,340 and 13,780 kpa], respectively.

Bats 3-c and 3-a are formed on an air accumulator similar to that used for bat 3-b, but provides greater MD directional strength for the bat. Bats 3-c and 3-d are applied to the hydraulic jet train while transporting at a speed of 13.6 yd / m [12.4 m / min]. For bat 3-c, one side of the bat is successively applied to one jet train supplied at a pressure of 1,500 psi [10,304 kpa] through orifice set E on screen support C, and then through orifice set C on screen support B. Apply to one jet train supplied at a pressure of 500 psi [3,450 kpa] and four jet trains supplied at a pressure of 2,000 psi [13,780 kpa] via orifice set D. Subsequently, it is applied continuously to the other side of the bat identically to one side on screen support B, except that the first jet train is removed. This process is repeated for bat 3-d, except that two jet rows (only the first face of the bat) are used instead of the first jet row, the first of the two jet rows is the orifice set B Is supplied at a pressure of 1,300 psi [8,960 kpa] and the second row is supplied at a pressure of 500 psi [3,450 kpa] via orifice set E.

The energy required to form the total Exl product, four bats into the nonwovens of the present invention and the characteristics of the resulting nonwovens are summarized in Table 4. The average strip tensile strength plotted in the figures clearly shows that the inventive midwoven fabric has advantages over the preceding comparable midwoven fabrics.

TABLE 4

* Footnotes for units of strip tensile strength are given in Table 3.

** Alternate Cycle

Example 4

In this example, polyethylene terephthalate staple fibers of different length and fineness are mixed together to form a bat and then treated with circumferential water flow to obtain a strong, flawless middle woven fabric of the present invention.

Three batts of mixed polyester fibers were prepared by the same air-integration method as used in Example 2. 50/50 fiber ratio with 1/4 in. [3.2 cm] in length and 6 denier [6.7 dtex] in fiber and 1/4 in [0.64 cm] in length and 1.35 denier [1.5 dtex] 2 bats, labeled 4-a and 4-b, are prepared using the mixture mixed. The third bat 4-c contains a 67/33 mixture of these fibers. These bats are transported at a rate of 10 yd / min [9.14 m / min] via the circumferential stream of water supplied through orifice set D while continuously supporting the bats on screens C, A and B. On screens C and A the jet enters through one surface of the bat and on screen B the jet enters through the opposite surface. Continuous jet feed pressures are presented in Table 5. The energy required to process three batts and the total Exl product are listed in Table 6 depending on the characteristics of the resulting nonwoven fabric. The average strip tensile strength of the nonwovens was plotted in the figure. It is clear from the data that the nonwovens of the present invention are advantageous in tensile strength over similar preceding nonwovens of the same weight.

TABLE 5

TABLE 6

* Footnotes for units of strip tensile strength are given in Table 3.

** Alternate Cycle

Example 5

This example is a nylon 66 staple fiber with a length of 1.5 inches [3.8 cm], 15 deniers [16.7 dtex] and a nylon 66 staple with a length of 1/4 inch [0.63 cm] and 1.8 deniers [2 dtex] The preparation of the nonwovens of the present invention from a 50/50 mixture of fibers is described. The fiber mixture is formed into a bat using an air accumulator of the type described in US Patent No. 3,797,074 to Japiroglu. The bat is then transported through the hydraulic jet train at a speed of 8.0 yd / min [7.3 m / min] while supporting the bat on the screen. Continuous processing is as follows:

Jet is applied to one surface of the bat while supporting the bat on screens C and B and then jetted to the other surface of the bat while supporting the bat on screen E. This treatment resulted in a strong, rust-resistant, tightly woven midwoven fabric whose properties are summarized in Table 7. As can be seen by plotting the average strip tension over unit weight, the nonwoven fabric of the present invention in tensile strength is much stronger than the nonwoven fabrics of the prior art.

TABLE 7

* Footnotes: 1. The unit of strip tensile strength is (lb / in) / (oz / yd ² ).

2. Units of strip tensile strength values in parentheses are (N / cm) / (g / m²).

Claims (8)

For seamless nonwoven fabrics, the unit weight of the nonwoven fabric is in the range of 200 to 850 g / m 2, grab strength of at least 160 N / cm, strip tensile strength of at least 0.26 (N / cm) / (g / m 2) A nonwoven comprising essentially staple fibers of a hydraulically entangled synthetic organic polymer, wherein the tear resistance is at least 50 alternating cycles. The unit weight is in the range of 240 to 510 g / m 2, the grab strength is in the range of 245 to 875 N / cm, and the strip tensile strength of 0.36 to 0.77 (N / cm) / (g / m 2). A nonwoven fabric having a range, having at least 90 alternating extension cycles, and having a jet track of 3 to 10 / cm. 2. The woven fabric of claim 1, wherein the staple fibers have a fineness of 1 to 18 dtex and a length of 0.6 to 5 cm. 3. The heavy woven fabric of claim 1, wherein the polymer is poly (p-phenylene terephthalamide). 3. The heavy woven fabric of claim 1, wherein the polymer is poly (m-phenylene isophthalamide). The midwoven fabric of Claim 1 or 2 whose polymer is a pulley (ethylene terephthalate). In a method for producing a seamless nonwoven fabric by treating a bat made of staple fibers of a synthetic organic polymer with a column of fine columnar water and moving vertically with respect to the heat of the water while supporting the bat on a pore screen, And fabrics were prepared from bats having staple fibers in the range of 0.6 to 5 cm in length and having a fineness in the range of 1 to 18 dtex and having a unit weight of 200 to 850 g / m 2, the bat being at the surface of the bat immediately after precompression. Wet treatment of the stream of water applied to a portion of the staple fiber through the through to the opposite surface of the bat (the heat of the water flow is spaced at a frequency of 3 to 10 / cm, supplied from an orifice of 0.13 to 0.22 mm in diameter) Method for producing a heavy fabric, characterized in that. The method of claim 7, wherein the unit weight ranges from 240 to 510 g / m 2, the length of the fiber ranges from 1.3 to 3.8 cm, the fineness ranges from 1.4 to 2.5 dtex, and the orifice frequency ranges from 3 to 6 / cm. And wherein the pressure of the water stream supplied is in the range of 6,890 to 22,740 kpa.

Images