TW202239356A - Non-woven fabric, carpet and method for preparing the same - Google Patents

Abstract

The present application relates to a non-woven fabric, a carpet and a method for preparing the same. According to the present application, a non-woven fabric, a carpet and a method for preparing the same, which are excellent in shape stability such as improving the problem of curling, can be provided. In addition, the present application can provide a non-woven fabric capable of quantitatively evaluating and predicting the shape stability and a method for preparing the same.

Description

Nonwoven fabric, blanket and method for its preparation

This application relates to a kind of non-woven fabric, blanket and its preparation method. More specifically, the present application relates to a spunbonded nonwoven fabric, a blanket and a method for preparing the same. [CROSS-REFERENCE TO RELATED APPLICATIONS]

This application claims the rights and interests of Korean Patent Application No. 10-2020-0187593 filed with the Korea Intellectual Property Office on December 30, 2020, the disclosure of which is incorporated herein by reference in its entirety.

Carpets are produced by a tufting process in which carpet yarns (bulked continuous filament (BCF) yarns) are inserted in the nonwoven fabric used for the backing (or primary backing) fabric. Also, non-woven fabrics (backing fabrics) and carpets receive significant external forces (such as physical pressure or heat) during the manufacturing process.

For example, in the process of making nonwoven fabrics, external forces (such as heat, tension, and cooling) are applied during the steps of making yarn. And high temperature and pressure are required to bond the nonwoven web (for example, to fix the mesh shape). In addition, in the tufting process, the nonwoven fabric is damaged when pierced by a needle, and in the back coating process, heating and cooling may be applied.

The manufacturing process as described above imposes potential stress on the non-woven fabric and carpet, thereby deteriorating the shape stability and mechanical properties of the non-woven fabric and carpet.

[technical problem]

The purpose of this application is to provide a kind of non-woven fabric and its preparation method.

Another object of the present application is to provide a nonwoven fabric with improved shape stability and a method for its production.

Another object of the present application is to provide a nonwoven fabric with excellent mechanical properties and a method for its preparation.

Another object of the present application is to provide a nonwoven fabric that can quantitatively evaluate and predict shape stability.

Yet another object of the present application is to provide a method for the production of nonwovens that can quantitatively evaluate and predict the shape stability of nonwovens, such as adjusting and evaluating (or confirming) the potential stress index of nonwovens during the production process.

Another object of the present application is to provide a non-woven fabric and a blanket comprising the non-woven fabric.

The above and other objects of the present application can be solved by the invention of the present application described in detail below. [Technical solution]

In one aspect, the present application relates to a method for making a nonwoven fabric. In particular, the method relates to a method for preparing long-fiber spunbond nonwovens.

According to the present application, the method includes: bonding the mesh (eg, fixing the shape of the mesh); applying an oil; and then applying heat to relax potential stresses. More specifically, the method includes: a first step of melting a high melting point polyester having a melting point ( _TH ) and a low melting point polyester having a melting point (T _L ) lower than the melting point ( _TH ) spinning to produce a web; a second step, bonding the web; a third step, applying a finish to the bonded web; and a fourth step, applying heat so that the potential of the nonwoven fabric to which the finish is applied A stress index of 5.00 or less.

The method can effectively reduce the potential stress left in the nonwoven fabric.

As a result of experimental confirmation, when the weight of the nonwoven fabric is low, the stress value tends to be relatively low, and when the weight of the nonwoven fabric is high, the stress tends to be high. However, even if a nonwoven exhibits relatively low stress, the degree of curling is not necessarily reduced. Therefore, consideration of both weight (basis weight) and stress values that affect the shape stability (dimensional stability, morphological stability, or durability) of nonwoven fabrics is important in predicting the degree of curling of mats as end products in the process of making nonwoven fabrics and Plays an important role in reducing the occurrence of frizz.

As a result of earnest studies in consideration of the above-mentioned problems, the inventors of the present application have found that when heat is applied to the nonwoven fabric applied with the oil agent, so that the potential stress index can be adjusted to 5.00 or less, the nonwoven fabric and the The mechanical properties (and its homogeneity) of the carpets it produces, as well as the dimensional stability, complete this disclosure.

The potential stress index is a value in which the stress of the nonwoven fabric measured according to the German Industrial Standard (Deutsche Industrie Norm, DIN) 53369 is divided by the basis weight (grams per square meter) of the nonwoven fabric, as described in the following experimental examples. Specifically, the potential stress index is a value in which the cooling stress (centinewton (cN)) is divided by the unit weight (gram/square meter) of the nonwoven fabric, which is regarded as a dimensionless value. In this regard, the cooling stress (centinewtons) is measured according to DIN 53369 after exposing the nonwoven to a temperature of 180° C. within 5 minutes and cooling the nonwoven at room temperature for 1 minute. In some cases, stress (thermal stress) can be measured during heat treatment of the nonwoven. In this case, the time for exposing the nonwoven fabric to heat of 180° C. may be within 4 minutes, within 3 minutes, or within 2 minutes.

In this way, the method of the present application includes the step of adjusting the latent stress index of the nonwoven during the manufacturing process of the nonwoven. Thereby, since the potential stress of the nonwoven fabric is evaluated (or confirmed) as a numerical value in the step, it is possible to quantitatively evaluate and execute a process capable of improving the shape stability of the nonwoven fabric. Therefore, prediction and evaluation of the shape stability of the nonwoven fabric can also be performed quantitatively.

In one example, references herein to an article, the nature of the article, and the process conditions for producing the article, when they are affected by heat or temperature, can be room temperature unless otherwise stated. At this time, the term "room temperature" means a temperature in a state that is not particularly warmed or cooled, and may mean, for example, a temperature within a range of 15°C to 30°C.

Now, each step related to the preparation method of the present application will be explained in detail.

The method includes a first step of melt spinning a high melting point polyester having a melting point ( _TH ) and a low melting point polyester having a lower melting point ( _TL ) than the melting point ( _TH ) to produce a mesh.

The shape of the net is not particularly limited. For example, the mesh can be isotropic or anisotropic in shape.

In an exemplary embodiment, the method can produce a web comprising 80% to 92% by weight high-melt polyester yarn and 8% to 20% by weight low-melt polyester yarn. In this context, the term "yarn" is used interchangeably with the term "filament".

Specifically, the lower limit of the content of the low-melting point polyester yarn may be, for example, 8.5 wt% or more, 9.0 wt% or more, 9.5 wt% or more, 10.0 wt% or more %, 10.5% by weight or greater than 10.5% by weight, 11.0% by weight or greater than 11.0% by weight, 11.5% by weight or greater than 11.5% by weight, 12.0% by weight or greater than 12.0% by weight, 12.5% by weight or greater than 12.5% by weight, 13.0% by weight or greater than 13.0 wt%, 13.5 wt% or greater than 13.5 wt%, 14.0 wt% or greater than 14.0 wt%, 14.5 wt% or greater than 14.5 wt%, 15.0 wt% or greater than 15.0 wt%, 15.5 wt% or greater than 15.5 wt% , 16.0% by weight or greater than 16.0% by weight, 16.5% by weight or greater than 16.5% by weight, 17.0% by weight or greater than 17.0% by weight, 17.5% by weight or greater than 17.5% by weight, or 18.0% by weight or greater than 18.0% by weight. Also, the upper limit of the content of the low melting point polyester yarn may be, for example, 19.5% by weight or less, 19.0% by weight or less than 19.0% by weight, 18.5% by weight or less than 18.5% by weight, 18.0% by weight or less than 18.0% by weight, 17.5% by weight or less, 17.0% by weight or less than 17.0% by weight, 16.5% by weight or less than 16.5% by weight, 16.0% by weight or less than 16.0% by weight, 15.5% by weight or less 15.5% by weight, 15.0% by weight or less 15.0% by weight, 14.5% by weight or less than 14.5% by weight, 14.0% by weight or less than 14.0% by weight, 13.5% by weight or less than 13.5% by weight, 13.0% by weight or less than 13.0% by weight, 12.5% by weight or less than 12.5% by weight, 12.0 % by weight or less than 12.0% by weight, 11.5% by weight or less than 11.5% by weight, 11.0% by weight or less than 11.0% by weight, 10.5% by weight or less than 10.5% by weight, or 10.0% by weight or less than 10.0% by weight. When the content of the low-melting-point polyester performing the thermal bonding function is less than the above range, the thermal bonding effect is not significant. Furthermore, when the content of the low-melting point polyester exceeds the above range, the degree of contact between fibers increases and the movement between fibers is restricted. Therefore, when the needles penetrate the nonwoven fabric (or primary base fabric) during the tufting process, the degree of damage to fibers becomes severe, and the tensile strength properties of the nonwoven fabric deteriorate.

In an exemplary embodiment, according to the method described above, a web comprising high melting point polyester yarns having a fineness of 7.0 denier to 10.0 denier may be produced. In addition, when the fineness of the high-melting point polyester yarn is smaller than the above range, the filaments are thin, and the number of filaments per unit area is large, whereby filament breakage may occur during the tufting process, and product quality (for example, uniform resistance) may deteriorate. In addition, when the fineness of the high-melting point polyester yarn exceeds the above range, the cooling of the filaments is insufficient, which makes it difficult to produce a product with a uniform shape, and may deteriorate the height uniformity of the BCF yarn during the tufting process.

In an exemplary embodiment, according to the present method, a web comprising low-melt polyester yarns having a fineness of 2.0 denier to 5.0 denier may be produced. When the fineness of the low melting point polyester yarn is smaller than the above range, the spinnability is poor. And when the fineness of the low-melting point polyester yarn exceeds the above-mentioned range, product quality (for example, uniformity) may deteriorate due to a bunching phenomenon in which filaments adhere to each other.

In an exemplary embodiment, according to the method, a high-melting polyester yarn having a fineness of 7.0 to 10.0 denier and a low-melting polyester yarn having a fineness of 2.0 to 5.0 denier can be produced. net.

Fineness can be ensured, for example, by adjusting the diameter of a spinneret used during spinning, the discharge amount during spinning, and the like.

_In an exemplary embodiment, according to the present method, _a ratio (N ₁ /N ₂ ) meshes in the range of 2.0 to 5.0. Specifically, the lower limit of the ratio (N ₁ /N ₂ ) may be, for example, 2.1 or greater, 2.2 or greater than 2.2, 2.3 or greater than 2.3, 2.4 or greater than 2.4, or 2.5 or greater, and its upper limit may be, eg, 4.5 Or less than 4.5, 4.0 or less than 4.0, 3.5 or less than 3.5, or 3.0 or less. When the ratio exceeds the above-mentioned range, that is, when the high-melting point component and the lower melting point component are much more abundant, bonding points between filaments are insufficient, which makes it difficult to apply sufficient strength. On the other hand, when the ratio is smaller than the above-mentioned range, bonding points increase, and freedom between filaments (eg, movement between fibers) is restricted, which may cause damage to the fibers, for example, during tufting.

In an exemplary embodiment, the high melting point polyester may have a melting point ( _TH ) of 250°C or greater. Specifically, the lower limit of the melting point ( _TH ) of the high melting point polyester may be, for example, 255°C or higher, 260°C or higher, 265°C or higher, or 270°C or higher. The upper limit of the melting point (T _H ) of the high melting point polyester is not particularly limited, and for example it may be 290°C or less, 285°C or less than 285°C, 280°C or less, 275°C or less, 270°C °C or less than 270 °C, 265 °C or less, or 260 °C or less.

In an exemplary embodiment, the melting point (T _L ) of the low melting point polyester may be less than 250°C. Specifically, the upper limit of the melting point ( _TL ) of the low-melting polyester may be, for example, 245°C or less, 240°C or less, 235°C or less, 230°C or less, 225°C, or Less than 225°C, 220°C or less than 220°C, 215°C or less than 215°C, 210°C or less than 210°C, 205°C or less than 205°C, 200°C or less than 200°C, 195°C or less than 195°C, 180°C or less 180°C, 175°C or less, 170°C or less, 165°C or less, 160°C or less, or 155°C or less. In addition, the lower limit thereof may be, for example, 150°C or higher, 155°C or higher, 160°C or higher, 165°C or higher, 170°C or higher, 175°C or higher, 180°C ℃ or greater than 180°C, 185°C or greater than 185°C, 190°C or greater than 190°C, 195°C or greater than 195°C, 200°C or greater than 200°C, 205°C or greater than 205°C, 210°C or greater than 210°C, 215°C Or greater than 215°C, 220°C or greater than 220°C, 225°C or greater than 225°C, or 230°C or greater. When the melting point temperature of the low-melting polyester is lower than the above range, the low-melting polyester component is easily melted by heat applied during the process related to the nonwoven fabric, whereby the nonwoven fabric (or primary base fabric) may be cracked and thermally shrunk. In addition, when the melting point temperature of the low-melting polyester exceeds the above-mentioned range, the flexibility of the nonwoven fabric becomes low, and the difference in elongation from the coating resin used in the production of the carpet becomes large, which causes the edge of the carpet to rise as the blanket is used. The problem becomes serious with the lapse of the time period.

In an exemplary embodiment, the intrinsic viscosity (IV) of the high melting point polyester may be 0.640 or greater than 0.640. For example, the lower limit of the intrinsic viscosity of the high melting point polyester may be, for example, 0.645 or greater than 0.645 or 0.650 or greater. The upper limit thereof is not particularly limited, but may be, for example, 0.700 or less.

In an exemplary embodiment, the intrinsic viscosity (IV) of the low-melting polyester may be 0.725 or greater. Specifically, the lower limit of the intrinsic viscosity of the low-melting polyester may be, for example, 0.750 or greater, 0.800 or greater, 0.850 or greater, or 0.900 or greater. The upper limit thereof is not particularly limited, but may be, for example, 0.950 or less.

Regarding the high melting point polyester and the low melting point polyester, the type of polyester is not particularly limited. For example, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polynaphthalene terephthalate may be used. In particular, at least one or more of the polyesters listed above may be included in the web as the polyester component.

In an exemplary embodiment, the low melting point polyester may be a copolyester. For example, the low melting point polyester may be a polyester copolymerized with adipic acid, a polyester copolymerized with isophthalic acid, or a polyester copolymerized with adipic acid and isophthalic acid. These copolymers can be prepared by adding comonomers such as adipic acid or isophthalic acid during the polymerization process.

In an exemplary embodiment, spinning may be performed at a temperature above the melting point ( _TH ) of the high melting point polyester (eg, a temperature of 260° C. or greater than 260° C.). Such spinning can be performed using known equipment.

Although not particularly limited, spinning may be performed at a speed ranging from 3500 m/min to 6000 m/min.

In one exemplary embodiment, two polyesters can be spun through each hole in the same or different nozzles of the spinneret while cooling simultaneously, and thus can be solidified. The cooling method is not particularly limited, and can be performed, for example, by using cooling air at a suitable temperature or atmospheric temperature (room temperature).

In an exemplary embodiment, the filaments may be drawn at a predetermined draw ratio. For example, the cooled filaments can be drawn at a predetermined spinning speed, and each filament can be separated at regular intervals.

The method includes a second step of gluing the web. Specifically, the second step may be a step of applying heat to the mesh to bond the mesh. The webs can be bonded by corresponding steps and so-called shape-fixed nonwovens can be obtained.

Applying heat to the web to bond the web can be performed by known methods. By way of example, rolls (such as calender rolls or embossing rolls) or rolls or hot air through (HAT) can be used. At this time, pressing can be performed together. The shape of the rolls, the method of applying the hot air, and the means or methods of maintaining each thermal bonding temperature (or supplying heat to the web) can be appropriately selected by those skilled in the art according to known techniques.

In an exemplary embodiment, the method passes the web through a roll having a first thermal bonding temperature (T ₁ ) and applies a second thermal bonding temperature (T ₂ ) to the web that has passed the roll, thereby enabling Glue the net. That is, specifically, the second step may be performed by passing the web through rolls maintained at a first thermal bonding temperature (T ₁ ) and applying a second thermal bonding temperature (T ₂ ) to execute. At this time, the first thermal bonding temperature (T ₁ ) may be a temperature equal to or lower than the second thermal bonding temperature (T ₂ ). Although not particularly limited, the web may pass between two rolls. In this case, the pressing of the web can be performed between the two rollers.

In an exemplary embodiment, the second thermal bonding temperature (T ₂ ) of the hot air may be equal to or higher than the first thermal bonding temperature (T ₁ ).

In an exemplary embodiment, the first thermal bonding temperature (T ₁ ) may be in the range of 120°C to 190°C. Appropriate shape stability can be imparted to the nonwoven fabric at the corresponding temperature.

In an exemplary embodiment, the second thermal bonding temperature (T ₂ ) of the hot air may be in the range of 140°C to 240°C. Appropriate shape stability can be imparted to the nonwoven fabric at the corresponding temperature.

In an exemplary embodiment, the second thermal bonding temperature (T ₂ ) may be higher than the first thermal bonding temperature (T ₁ ). Specifically, the temperature difference between the first thermal bonding temperature (T ₁ ) and the second thermal bonding temperature (T ₂ ) may be in the range of 20° C. to 60° C. (T ₂ > T ₁ ). Appropriate shape stability can be imparted to the nonwoven fabric at the corresponding temperature.

The method includes a third step of applying (coating) an oil to the bonded web (eg, nonwoven fabric).

The oil agent can form a coating (or coating film) on the surface of the web (nonwoven fabric) or the filaments forming the web. Since the coating film reduces the friction that occurs between the needle and the nonwoven fabric when the needle penetrates in the subsequent tufting process, damage to the web or the fibers forming the web can be prevented. In addition, since the heat generated by friction is reduced by the oil film, the life of the needle can be extended.

In an exemplary embodiment, an oil agent may be applied (coated) to the bonded web (or the filaments forming the bonded web) to have 0.05% by weight in 100% by weight of the total weight of the nonwoven fabric. Or a content greater than 0.05% by weight. At this time, the total weight of the nonwoven fabric used as the basis for the finish content can be, for example, the weight of the nonwoven fabric to which the finish is applied in the third step, the weight of the nonwoven fabric that has undergone the web bonding step, or by performing step 4 described below. The weight of the nonwoven fabric produced. Specifically, the lower limit of the oil content may be, for example, 0.1% by weight or more, 0.15% by weight or more than 0.15% by weight, 0.20% by weight or more than 0.20% by weight, 0.25% by weight or more than 0.25% by weight, 0.30% by weight % or greater than 0.30% by weight, 0.35% by weight or greater than 0.35% by weight, 0.40% by weight or greater than 0.40% by weight, 0.45% by weight or greater than 0.45% by weight, or 0.50% by weight or greater than 0.50% by weight. In addition, the upper limit of the oil agent content may be, for example, 5.0 wt% or less, 4.5 wt% or less, 4.0 wt% or less, 3.5 wt% or less, 3.0 wt% or Less than 3.0 wt%, 2.5 wt% or less than 2.5 wt%, 2.0 wt% or less than 2.0 wt%, 1.5 wt% or less than 1.5 wt%, or 1.0 wt% or less than 1.0 wt%. When the content of the oil agent is less than the above range, the content of the oil agent is insufficient, and thus the oil agent cannot be uniformly penetrated into the filaments forming the nonwoven fabric, which makes it difficult to form a sufficient oil coating film, and thus the filaments may be tufted damaged during processing. In addition, when a small amount of oil is used, the performance of the tufting process deteriorates, and the BCF yarn deteriorates. In addition, when the content of the oil agent exceeds the above range, the slip increases, which is not suitable for the winding process, and the tension control is difficult. In addition, excessive finish adheres to the needle bars used in the tufting process, and foreign substances such as dust accumulate on the finish adhered to the needle bars, making it possible to prevent carpet yarns from being inserted at uniform intervals in the tufting process .

The type of oil that can be used is not particularly limited. For example, a silicone-based oil or an ester-based oil can be used as the oil.

The method includes: a fourth step of applying heat so that the latent stress index of the nonwoven fabric applied with the oil agent is 5.00 or less. The inventors of the present application have experimentally confirmed that when the potential stress index exceeds 5.00, the shape stability is poor (for example, the degree of curling of the product is severe), as confirmed in the following experimental examples. The potential stress index can be obtained by dividing the cooling stress (centi-Newton) measured according to DIN 53369 by the unit weight of the nonwoven after exposing the nonwoven to a temperature of 180°C within 5 minutes and cooling the nonwoven at room temperature for about 1 minute (grams per square meter) to calculate.

In an exemplary embodiment, the bonded web (nonwoven fabric) may have a potential stress index of 5.00 or less in a machine direction or mechanical direction (MD).

In an exemplary embodiment, the bonded web (nonwoven) may have a potential stress index of 5.00 or less in the CD (cross direction or cross-machine direction).

In an exemplary embodiment, the bonded web (nonwoven) may have a potential stress index of 5.0 or less in MD and CD.

Specifically, in MD and/or CD, the upper limit of the potential stress index can be, for example, 4.9 or less than 4.9, 4.8 or less than 4.8, 4.7 or less than 4.7, 4.6 or less than 4.6, 4.5 or less than 4.5, 4.4 or less than 4.4, 4.3 or less than 4.3, 4.2 or less than 4.2, 4.1 or less than 4.1, or 4.0 or less than 4.0. In addition, the lower limit of the potential stress index may be, for example, 1.5 or greater, 2.0 or greater, 2.5 or greater, 3.0 or greater, or 3.5 or greater.

In an exemplary embodiment, the step of applying heat to relax (latent) stresses may be performed at a predetermined temperature T ₃ .

Specifically, the step of applying heat to relax the stress may be performed at a temperature T ₃ that satisfies Relational Expression 1 below. [Relational expression 1] 20°C ≤ melting point (T _L ) of low melting point polyester - temperature (T ₃ ) ≤ 60°C

That is, the melting point (T _L ) of the low-melting point polyester is greater than the temperature (T ₃ ), and the difference between the melting point (T _L ) and the temperature (T ₃ ) of the low-melting point polyester may be in the range of 20°C to 60°C Inside.

When step ₄ is carried out while applying heat at a temperature T3 satisfying relational expression 1, in addition to drying the coated oil agent, it is possible to effectively reduce the amount of time spent in the process of preparing the nonwoven fabric (for example, for bonding to the net). Potential stresses imposed on the nonwoven (or web) during thermal bonding steps, etc.). Therefore, the shape instability of the product due to potential stress (for example, curling or warping) can be improved.

Specifically, the lower limit of the temperature difference (ΔT = T _L - T ₃ ) may be, for example, 25°C or greater, 30°C or greater, 35°C or greater, 40°C or greater, 45°C Or greater than 45°C, 50°C or greater than 50°C, or 55°C or greater than 55°C, and the upper limit may be, for example, 55°C or less than 55°C, 50°C or less than 50°C, 45°C or less than 45°C, 40°C or Less than 40°C, 35°C or less, 30°C or less, or 25°C or less. When the temperature difference (ΔT = T _L - T ₃ ) is less than the above range, the stiffness of the nonwoven fabric may increase, resulting in a decrease in the tufting efficiency, an increase in the width shrinkage of the nonwoven fabric, and a deepening of the deformation of the initial physical properties of the nonwoven fabric, which makes it difficult for the nonwoven fabric to be used as Used for tile carpet backing. In particular, when a condition smaller than the above temperature difference (ΔT = T _L - T ₃ ) is given, the tear strength of the nonwoven fabric is significantly reduced, and thus there is a problem that the primary base fabric of the tile carpet is torn after tufting. Conversely, when the temperature difference (ΔT = T _L -T ₃ ) exceeds the above range, it is difficult to effectively reduce the potential stress.

A method of applying heat at temperature T ₃ satisfying Relational Expression 1 is not particularly limited. For example, it may be considered to use known tools or methods (such as using a drum dryer or applying hot air) to provide the temperature T ₃ satisfying Relational Expression 1.

In an exemplary embodiment, the temperature T ₃ at which the step of relaxing the stress by applying heat is performed may satisfy the following relational expression 2. Considering the entire process of preparing the nonwoven fabric, the temperature T ₃ satisfying Relational Expression 2 is advantageous in relaxing potential stress. [Relational expression 2] First thermal bonding temperature (T ₁ ) ≤ temperature (T ₃ ) ≤ second thermal bonding temperature (T ₂ )

In an exemplary embodiment, the step of relaxing the stress by applying heat may be performed at the temperature T3 for ₁₀ seconds to 130 seconds. For example, the time to perform the step of relaxing the stress by applying heat at temperature T3 can be ₂₀ seconds or more, 30 seconds or more, 40 seconds or more, 50 seconds or more seconds, 60 seconds or more, 70 seconds or more, 80 seconds or more, 90 seconds or more, 100 seconds or more, 110 seconds or more, or 120 seconds or more Second. In addition, the upper limit thereof may be, for example, 120 seconds or less, 110 seconds or less, 100 seconds or less, 90 seconds or less, 80 seconds or less, 70 seconds or less, 60 seconds or less, 60 seconds or less, 50 seconds or less, 40 seconds or less, or 30 seconds or less. When the time is less than the above range, the nonwoven fabric may not be sufficiently relaxed, and therefore, the effect due to the reheating treatment may not be sufficiently obtained. In addition, when the time exceeds the above range, not only the physical properties of the nonwoven fabric or the base fabric produced therefrom are deformed, but also the production equipment becomes too large, the productivity may decrease and the production cost may increase.

In an exemplary embodiment, the nonwoven fabric prepared according to the method may have a thickness ranging from 0.20 mm to 0.60 mm. Specifically, the lower limit of the thickness of the nonwoven fabric can be, for example, 0.25 mm or more, 0.30 mm or more, 0.35 mm or more, or 0.40 mm or more, and the upper limit can be, for example, 0.55 mm or less. 0.55 mm, 0.50 mm or less, 0.45 mm or less, or 0.40 mm or less.

In an exemplary embodiment, the nonwoven fabric prepared according to the method may have a unit weight, ie, a basis weight, of 70 g/m 2 to 140 g/m 2 . Specifically, the lower limit of the basis weight of the bonded web may be, for example, 75 g/m2 or greater, 80 g/m2 or greater, 85 g/m2 or more than 85 g/m2, 90 g/m2 or more than 90 g/m2, 95 g/m2 or more than 95 g/m2, 100 g/m2 or more than 100 g/m2 square meter, or 105 grams/square meter or greater than 105 grams/square meter, and its lower limit may be, for example, 135 grams/square meter or less than 135 grams/square meter, 130 grams/square meter or less than 130 grams/square meter, 125 grams/square meter or less than 125 grams/square meter, 120 grams/square meter or less than 120 grams/square meter, 115 grams/square meter or less than 115 grams/square meter , 110 grams/square meter or less than 110 grams/square meter, 105 grams/square meter or less than 105 grams/square meter, 100 grams/square meter or less than 100 grams/square meter, 95 grams/square meter Meter or less than 95 g/m2, or 90 g/m2 or less than 90 g/m2. When the above range is satisfied, appropriate levels of brightness and mechanical properties can be secured.

In an exemplary embodiment, the nonwoven fabric prepared according to the method may have both the above-mentioned thickness and basis weight. For example, the nonwoven fabric may have a thickness of 0.30 mm to 0.40 mm and a basis weight of 85 g/m2 to 95 g/m2. Alternatively, the nonwoven may have a thickness of, for example, 0.35 mm to 0.55 mm and a basis weight of 90 g/m2 to 120 g/m2.

In another exemplary embodiment related to the present application, the present application relates to a non-woven fabric. The nonwoven fabric can be provided by the above-mentioned production method.

The non-woven fabric includes: high-melting-point polyester yarn and low-melting-point polyester yarn thermally bonded to each other; and an oil agent, and can satisfy a potential stress index of 5.00 or less. Specifically, high-melting point polyester yarns and low-melting point polyester yarns that are thermally bonded to each other form a non-woven fabric (or net), and the oil agent can be applied to each polyester yarn or non-woven fabric (or net) to form a coating (or coating). In addition, the potential stress index of the nonwoven fabric in MD and/or CD may be, for example, 5.0 or less. The specific potential stress index is the same as that set forth in the context of the preparation method.

In an exemplary embodiment, the potential stress index of the bonded web (nonwoven fabric) in the MD and CD directions may be 5.0 or less than 5.0. The specific potential stress index is the same as that set forth in the context of the preparation method.

In an exemplary embodiment, the nonwoven fabric may have a thickness ranging from 0.20 mm to 0.60 mm. The specific thickness is the same as explained in the content about the preparation method.

In an exemplary embodiment, the basis weight of the nonwoven fabric may be 70 g/m 2 to 140 g/m 2 . The specific basis weight of the nonwoven is the same as set forth in the context of the preparation method.

In an exemplary embodiment, the nonwoven fabric may include 80% to 92% by weight of high melting point polyester yarn and 8% to 20% by weight of low melting point polyester yarn. The specific weight ratio between the components is the same as that set forth in the content about the production method.

_In an exemplary embodiment, in the nonwoven fabric, the ratio _{(N 1 /} N ₂ ) Can be in the range of 2.0 to 5.0. The specific ratios of the numbers are the same as those set forth in the context of the preparation method.

The fineness of the high-melting-point polyester yarn and the low-melting-point polyester yarn included in the nonwoven fabric is the same as that described in the content about the production method.

The melting point of the polyester contained in each of the high-melting-point polyester yarn and the low-melting-point polyester yarn is the same as that described in the content about the production method.

The types of polyester contained in the high-melting point polyester yarn and the low-melting point polyester yarn are the same as described in the content about the production method.

In addition, components contained in the nonwoven fabric (such as components used to prepare the nonwoven fabric) and their characteristics are explained in the content about the production method, and descriptions thereof will be omitted.

In another example related to the present application, the present application relates to a method of making a carpet. The method may include inserting a carpet yarn on one surface of the nonwoven fabric prepared according to the above method using a needle.

Specifically, the method includes: a first step, melt-spinning a high-melting-point polyester having a melting point ( _TH ) and a low-melting-point polyester having a melting point ( _TL ) lower than the melting point ( _TH ) wire to produce a mesh; second step, bonding the mesh; third step, applying an oil agent (for example, non-woven fabric) to the bonded mesh; fourth step, applying heat so that the oil agent is applied The potential stress index of the nonwoven fabric is 5.00 or less; and a fifth step of inserting the carpet yarn on one surface of the nonwoven fabric using a needle. Carpet yarns may be, for example, BCF yarns.

Regarding the production method of the carpet, the descriptions of the first step to the fourth step and the like are as above.

The fifth step is the so-called tufting process, which can be performed using known methods and equipment. For example, tufting may be performed in loops using a predetermined gauge (eg, 1/10 gauge). In addition, a tufting process may be performed so that the carpet yarn has a predetermined fineness (eg, 500 denier to 1500 denier) and height (eg, 3.0 mm to 0.7 mm). With the tufting process, carpet yarns can be inserted to be visually identified at one surface of the nonwoven.

In an exemplary embodiment, the method for producing a carpet may further include a sixth step of applying the resin coating solution to the rear surface. The process of imparting shape stability to the carpet is called the so-called priming process. In this case, the back surface may mean, for example, a surface opposite to a surface on which the carpet yarn is visually recognized. In some cases, a glass mat may be used in a primer process together with a resin component, and hot air may be applied to dry the coating solution.

The type of resin contained in the coating liquid used for undercoating is not particularly limited. For example, the coating solution may include resin components such as polyvinyl chloride (polyvinyl chloride, PVC), polyethylene (polyethylene, PE), ethylene vinyl acetate (ethylene vinyl acetate, EVA) or styrene-butadiene rubber (styrene butadiene rubber, SBR). The coating solution as described above or the undercoat layer obtained therefrom may form one or more layers.

In one exemplary embodiment, the method may further include a seventh step of drying the resin coating solution applied to the bottom surface, and then cutting the obtained carpet into a predetermined size. After the steps are completed, a tile carpet can be prepared.

In the prepared tile carpet, curling in which four corners are lifted may occur. When the degree of curl is severe, it may not be possible to construct a tile carpet, and therefore, the degree of curl needs to be reduced. In related technical fields, such attempts have continued. As described above, according to the present application, by quantitatively confirming and evaluating the potential stress remaining in the nonwoven fabric during the nonwoven fabric manufacturing process, the curling problem of the carpet can be effectively managed and prevented.

In another example related to the present application, the present application relates to a carpet. The carpet includes a nonwoven fabric having the above characteristics and raw yarns inserted into the nonwoven fabric. The blanket improves the curling problem of corner lift.

In an exemplary embodiment, the carpet may be a tile carpet.

Other than that, since the structure and production method of the blanket are the same as above, they are omitted. [Beneficial effect]

According to the present application, there can be provided a nonwoven fabric, a carpet and a production method thereof which are excellent in shape stability (for example, the problem of curling is improved). In addition, the present application is effective in providing a nonwoven fabric capable of quantitatively evaluating and predicting shape stability and a method for producing the same.

Hereinafter, the actions and effects of the present disclosure will be described in more detail with reference to specific examples. However, these examples are presented for purposes of illustration and are not intended to limit the scope of the disclosure in any way. < Example and Comparative Example > Example 1

preparing a polyethylene terephthalate (PET) raw material (first component raw material) having an intrinsic viscosity (IV) of 0.645 and a melting temperature of 254° C.; and having an intrinsic viscosity (IV) of 0.920 and Copolymerized polyethylene terephthalate (Co-PET) raw material (second component raw material) with a melting temperature of 171 °C (Co-PET prepared using adipic acid as comonomer). Then, each of the above raw materials was spun using a spun-bonding preparation device at a spinning speed of 5,000 m/min and a spinning temperature of 270° C. to prepare filament fibers. At this time, adjust the fineness of the first component PET to 8.5 deniers, adjust the fineness of the second component Co-PET to 3.6 deniers, and mix the first component PET with the second component Co-PET The weight ratio (wt.%) was adjusted to 85:15. Furthermore, the ratio (N ₁ /N ₂ ) between the first number of filaments (N ₁ ) and the second number of filaments (N ₂ ) is adjusted to 2.3.

After the spun filament fibers are laminated in the form of a web on a moving conveyor net, they are primary bonded at a calendering temperature of 140°C and heated at a HAT hot air temperature of 175°C. Secondary bonding is carried out to prepare spunbond nonwovens. Then, the oil agent was applied to the nonwoven fabric so that the content of the oil agent was about 0.5% by weight based on 100% by weight of the total weight of the prepared nonwoven fabric. The finish-coated nonwoven had a basis weight of about 90 gsm and a thickness of about 0.34 mm. After coating with the oil agent, the following tensile strength, tear strength and latent stress index were measured.

The prepared nonwoven fabric (carpet backing) was put into a separate cylindrical heat treatment element, and subjected to reheat treatment at 150° C. for 20 seconds while moving at a speed of 30 m/min. After the reheat treatment, the following tensile strength, tear strength, shrinkage and latent stress index were measured.

In addition, tufting (1/10 gauge, blanket yarn (BCF) 1240 denier, pile yarn height 4.0 mm) was performed on the nonwoven fabric (blanket primary backing fabric). Then, a PVC liquid and a glass mat were coated at 6.4 kg/m2 on the base fabric in which the carpet yarns were tufted, thereby preparing a tile carpet. The curl values of the four corners of the tile carpet were measured (by Aachen evaluation) as described below for the final prepared tile carpet. Example 2

Nonwoven fabrics and blankets were prepared by the same process as described in Example 1 except that the reheat treatment was performed at a speed of 10 m/min for 60 seconds. Example 3

Except that the melting point and intrinsic viscosity (IV) of Co-PET used as the second component raw material are 226°C and 0.820 respectively, the spinning temperature of the second component raw material is 280°C, the calendering temperature is 180°C, and the HAT hot air temperature 205° C., and the reheat treatment was performed at a temperature of 205° C. at a speed of 30 m/min for 20 seconds, nonwoven fabrics and blankets were prepared by the same process as described in Example 1. Example 4

Nonwoven fabrics and blankets were prepared by the same process as described in Example 3, except that the reheat treatment was performed at a speed of 10 m/min for 60 seconds. Example 5

Nonwoven fabrics and blankets were prepared by the same procedure as described in Example 4, except that the reheat treatment temperature was set at 175°C. Comparative example 1

Nonwoven fabrics and blankets were prepared by the same procedure as described in Example 1, except that the reheat treatment was performed at a speed of 120 m/min for 5 seconds. Comparative example 2

Nonwoven fabrics and blankets were prepared by the same procedure as described in Example 1 except that reheat treatment was performed at a temperature of 160°C. Comparative example 3

Nonwoven fabrics and carpets were prepared by the same process as described in Example 1 except that the reheat treatment was performed at a temperature of 150° C. at a speed of 4 m/min for 150 seconds. Comparative example 4

Nonwoven fabrics and blankets were prepared by the same procedure as described in Example 3, except that the reheat treatment was performed at a temperature of 205° C. at a speed of 120 m/min for 5 seconds. Comparative Example 5

Nonwoven fabrics and blankets were prepared by the same procedure as described in Example 3 except that the reheat treatment was performed at a temperature of 220°C. Comparative example 6

Nonwoven fabrics and carpets were prepared by the same process as described in Example 3, except that the reheat treatment was performed at a temperature of 205° C. at a speed of 4 m/min for 150 seconds. Comparative Example 7

Nonwoven fabrics and blankets were prepared by the same process as described in Example 3, except that the reheat treatment was performed at a temperature of 100° C. at a speed of 5 m/min for 120 seconds.

The following is a comparison of the preparation process of the nonwoven fabrics of Examples and Comparative Examples. [Table 1] first component second component Web bonding conditions Potential stress index control condition Intrinsic viscosity (IV) / melting point (°C) Intrinsic viscosity (IV) / melting point (°C) T ₁ (°C) T ₂ (°C) T ₃ (°C) time (seconds) Example 1 0.645 / 254 0.920 / 171 140 175 150 20 Example 2 0.645 / 254 0.920 / 171 140 175 150 60 Example 3 0.645 / 254 0.820 / 226 180 205 205 20 Example 4 0.645 / 254 0.820 / 226 180 205 205 60 Example 5 0.645 / 254 0.820 / 226 180 205 175 60 Comparative example 1 0.645 / 254 0.920 / 171 140 175 150 5 Comparative example 2 0.645 / 254 0.920 / 171 140 175 160 20 Comparative example 3 0.645 / 254 0.920 / 171 140 175 150 150 Comparative example 4 0.645 / 254 0.820 / 226 180 205 205 5 Comparative Example 5 0.645 / 254 0.820 / 226 180 205 220 20 Comparative Example 6 0.645 / 254 0.820 / 226 180 205 205 150 Comparative Example 7 0.645 / 254 0.820 / 226 180 205 100 120 T ₁ : first bonding temperature T ₂ : second bonding temperature T ₃ : temperature of heat for adjusting the latent stress index. _T3 is the temperature applied during the above time ＜Method for evaluating physical properties＞

The following physical properties were evaluated for the nonwoven fabrics and/or carpets prepared in Examples and Comparative Examples, and the results are shown in Table 2 and Table 3 below. 1. Tensile strength (kgf/5cm)

Tensile strength was measured according to Korean Standard (KS) K 0521 (cut strip). Specifically, the spunbond nonwoven fabrics of Examples and Comparative Examples were prepared as samples having a size of 20 cm×5 cm. Tensile strength in each of the MD and CD directions was measured using a Universal Tensile Tester (Instron) when a tensile speed of 200 mm/min was applied to the specimen. The tensile strengths were measured before and after the reheat treatment used to measure the potential stress index. 2. Tear strength (kg force)

Tear strength was measured according to KS K 0536 (single tongue). Specifically, the spunbond nonwoven fabrics of Examples and Comparative Examples were prepared as samples having a size of 7.6 cm×20 cm. Tear strength in each of the MD and CD directions was measured using a Universal Tensile Tester (Instron) when a tensile speed of 300 mm/min was applied to the specimen. Tear strength was measured before and after the reheat treatment used to measure the potential stress index. 3. Potential stress index

The spunbond nonwoven fabrics of Examples and Comparative Examples were prepared as samples having a size of 5.0 cm×70 cm, and the potential stress was measured according to DIN 53369 (heat shrinkage and shrinkage force). Specifically, according to DIN 53369, a weight of 50 grams is used to fix the nonwoven and the thermal stress (centinewtons) can be measured in a chamber at 180° C. for 2 minutes. After 2 minutes required to measure the thermal stress value, the nonwoven fabric was exposed to air for 1 minute to measure the cooling stress (latent stress). Then, the measured cooling stress (centinewtons) was divided by the unit weight of the specimen (grams per square meter) and the potential stress index was obtained. Potential stress indices are treated as dimensionless values.

The tensile strengths were measured before and after the reheat treatment used to measure the potential stress index. 4. Width shrinkage (%)

Based on a width of 3.8 meters, that is, the width of a general nonwoven fabric used for a carpet backing, the rate of change before and after the reheat treatment was expressed as a shrinkage rate. Then, this value was calculated for the nonwoven fabrics prepared in Examples and Comparative Examples. Width shrinkage (%) =[(width of nonwoven fabric before reheat treatment)-(width of nonwoven fabric after reheat treatment)]/(width of nonwoven fabric before reheat treatment)×100

At this time, the width of the nonwoven fabric before the reheat treatment was 3.8 mm. 5. Curl (mm)

Curl is measured according to DIN EN 986 (Aachen test). Specifically, tile carpets (50 cm x 50 cm) were preheated in an oven at 60 °C for about 30 min. The preheated tile carpet was immersed in water containing 1% by weight of surfactant for about 30 minutes, and then preheated in an oven at 60° C. for 24 hours. Then, the curl height was measured after leaving the preheated tile carpet at room temperature for 48 hours. At this time, the curl is an average value of curl heights measured for each of the four corners. [Table 2] type Tensile strength before reheating (kgf/5cm) Tear strength before reheating (kgf) Potential stress index before reheating MD cd MD cd MD cd Example 1 21.5 21.1 9.4 9.6 6.41 6.10 Example 2 23.4 23.2 8.6 8.5 6.52 6.26 Example 3 22.5 21.9 7.4 7.0 8.52 8.43 Example 4 23.9 24.0 7.3 7.1 8.69 8.62 Example 5 25.1 24.7 7.0 6.9 8.88 8.85 Comparative example 1 21.4 21.3 9.5 9.5 6.40 6.32 Comparative example 2 23.1 23.2 8.4 8.6 6.68 6.59 Comparative example 3 23.2 23.5 8.5 8.6 6.70 6.67 Comparative example 4 22.8 22.2 7.5 7.1 8.65 8.53 Comparative Example 5 23.7 23.8 7.2 7.1 8.74 8.80 Comparative example 6 25.0 24.8 6.4 6.4 9.10 9.08 Comparative Example 7 25.4 25.3 6.4 6.5 9.02 8.95 [table 3] type Tensile strength after reheat treatment (kgf/5cm) Tear strength after reheat treatment (kgf) Potential stress index after reheat treatment Width shrinkage (%) Bend (mm) MD cd MD cd MD cd Example 1 22.6 22.1 9.0 9.1 3.85 3.92 0.1 0.2 Example 2 23.9 24.0 7.8 8.0 3.52 3.26 0.4 0.1 Example 3 22.8 22.9 8.3 7.9 4.61 4.53 0.1 0.4 Example 4 24.0 24.4 7.8 7.4 4.31 4.38 0.4 0.3 Example 5 25.2 25.3 7.1 7.2 4.31 4.57 0.2 0.5 Comparative example 1 22.3 20.4 8.4 8.5 5.40 5.52 0.0 0.7 Comparative example 2 26.4 27.0 6.3 5.0 6.41 6.85 2.4 0.9 Comparative example 3 27.5 26.9 5.1 5.7 6.99 6.57 2.3 1.5 Comparative example 4 23.8 23.3 7.4 7.4 6.51 6.34 0.1 1.0 Comparative Example 5 29.0 28.8 5.7 5.4 11.10 12.45 3.1 4.3 Comparative Example 6 28.4 27.6 5.0 5.0 9.45 10.01 2.9 3.4 Comparative Example 7 26.5 26.7 6.3 6.6 9.00 8.64 0.0 3.8 *MD: machine direction *CD: cross direction

According to Table 2 and Table 3, it can be seen that when the potential stress index is adjusted to 5.0 or less by performing the reheating treatment under the same conditions as the examples, the average width shrinkage of the nonwoven fabric and the blanket Curl can be reduced at the same time. That is, according to the present application, a nonwoven fabric and a carpet having excellent shape stability can be provided.

On the other hand, comparing the degree of change in tensile strength and tear strength before and after the reheating treatment by the arithmetic mean, it can be seen that when the reheating treatment according to the example of the present application is performed, before the reheating treatment After that, the tensile strength and tear strength did not change much. This means that both mechanical properties and shape stability can be ensured by the reheat treatment according to the present application.

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Claims (20)

A method for preparing a nonwoven fabric, comprising: a first step of melting a high-melting-point polyester having a melting point ( _TH ) and a low-melting-point polyester having a melting point ( _TL ) lower than the melting point ( _TH ) spinning to produce a web; a second step of bonding the web; a third step of applying an oil to the bonded web; and a fourth step of applying heat so that the nonwoven fabric to which the oil is applied The potential stress index is 5.00 or less than 5.00 (in the fourth step, the potential stress index is to expose the nonwoven fabric to a temperature of 180 ° C within 5 minutes and cool the nonwoven fabric at room temperature for 1 Dimensionless value of the cooling stress (centinewtons) measured according to DIN 53369 divided by the unit weight of the nonwoven (g/m²) after minutes. The method for preparing a nonwoven fabric as described in claim 1, wherein: said fourth step is performed by applying heat for 10 seconds to 130 seconds at a temperature T ₃ satisfying the following relational expression 1: [relational expression 1] 20°C ≤ melting point (T _L ) of low melting point polyester - temperature (T ₃ ) ≤ 60°C. The method for preparing non-woven fabric as described in Claim 1, It produces a web comprising 80% to 92% by weight of said high melting point polyester yarn and 8% to 20% by weight of said low melting point polyester yarn. The method for preparing non-woven fabrics as described in claim 3, It produces a web comprising said high melting polyester yarn having a fineness of 7.0 to 10.0 denier and said low melting polyester yarn having a fineness of 2.0 to 5.0 denier. The method for preparing a nonwoven fabric as described in Claim 3 or 4, which produces the number (N ₁ ) (number of filaments) of the high-melting point polyester yarn and the number (N ₂ ) of the low-melting point polyester yarn ) ratio (N ₁ /N ₂ ) between meshes in the range of 2.0 to 5.0. The method for producing a nonwoven fabric according to claim 3, wherein: the melting point (T _H ) of the high melting point polyester is 250°C or higher, and the melting point (T H ) of the low melting point polyester ( T _L ) is 245°C or less. The method for preparing non-woven fabric as described in claim 1, wherein: The polyester is at least one selected from polyethylene terephthalate, polybutylene terephthalate and polynaphthyl terephthalate. The method for preparing non-woven fabric as described in claim item 7, wherein: The low-melting-point polyester is at least one copolymerized polyester of adipic acid and isophthalic acid. A method for producing a nonwoven fabric as claimed in claim 1, by passing the web through a roll having a first thermal bonding temperature (T ₁ ) and applying a second thermal bonding temperature to the web that has passed through the roll (T ₂ ) to bond the web, wherein the second thermal bonding temperature (T ₂ ) is a temperature equal to or higher than the first thermal bonding temperature (T ₁ ). The method for preparing a nonwoven fabric as claimed in claim 9, wherein: the first thermal bonding temperature (T ₁ ) is in the range of 120°C to 190°C, and the second thermal bonding temperature (T ₂ ) is in the range of 140°C to 240°C range. The method for preparing a nonwoven fabric according to claim 9 or 10, wherein: the temperature T ₃ satisfies the following relational expression 2: [Relational expression 2] First thermal bonding temperature (T ₁ )≤temperature (T ₃ ) ≤ second thermal bonding temperature (T ₂ ). The method for preparing non-woven fabric as described in claim 1, wherein: An oil agent is applied to the bonded web so as to have a content of 0.05% by weight or more based on 100% by weight of the total weight of the nonwoven fabric. A non-woven fabric comprising high-melting-point polyester yarns and low-melting-point polyester yarns thermally bonded to each other; and an oil, wherein the non-woven fabric has a potential stress index of 5.00 or less (in this case, the potential stress index is wherein the non-woven fabric is exposed to a temperature of 180° C. within 5 minutes and the non-woven fabric is cooled at room temperature for 1 Dimensionless value of the cooling stress (centinewtons) measured according to DIN 53369 divided by the unit weight of the nonwoven (g/m2) after minutes). The nonwoven fabric as claimed in claim 13, It has a thickness in the range of 0.20 mm to 0.60 mm and a basis weight in the range of 70 g/m² to 140 g/m². The nonwoven fabric as claimed in claim 13, It includes 80% to 92% by weight of the high melting point polyester yarn and 8% to 20% by weight of the low melting point polyester yarn. _The nonwoven fabric according to claim ₁₃ , wherein: the ratio (N ₁ /N ₂ ) in the range of 2.0 to 5.0. The nonwoven fabric as claimed in item 13, wherein: The high melting point polyester yarn has a fineness of 7.0 denier to 10.0 denier, and the low melting point polyester yarn has a fineness of 2.0 denier to 5.0 denier. The nonwoven fabric according to claim 13, wherein: the melting point (T _H ) of the high melting point polyester is 250°C or higher, and the melting point (T _L ) of the low melting point polyester is 245 °C or less than 245 °C. A method for preparing a blanket comprising: On one surface of the nonwoven fabric prepared as described in Claim 1, a carpet yarn was inserted using a needle. A blanket comprising the nonwoven fabric as claimed in claim 13; and raw yarns inserted into the nonwoven fabric.