KR20170112571A - Fiber composites having excellent sound absorption, water absorption and heat insulation, Non-woven fabric containining the same and Preparing method thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fibrous aggregate, a nonwoven fabric made using the same, and an application product of the nonwoven fabric. More specifically, the nonwoven fabric manufactured using the fibrous aggregate of the present invention has excellent lightweight, A noise absorbing material, a heat insulating material and / or a water absorbing material.

Description

TECHNICAL FIELD [0001] The present invention relates to a fiber aggregate having excellent sound absorption properties, water absorption properties, and heat retention, a nonwoven fabric including the same,

The present invention relates to a fibrous aggregate obtained by introducing a hollow binder fiber to improve lightweight properties and to ensure moisture absorption and heat insulation in addition to sound absorption, a nonwoven fabric produced using the same, a method for producing the same, and an application product thereof.

Such as a vacuum cleaner, a dishwasher, a washing machine, an air conditioner, an air purifier, a computer, a projector, and the like, and the problem of noise pollution becomes more serious. Therefore, efforts to block or reduce the noise generated from various noise sources in the modern life are continuing, and in the developed countries, the legal regulations to regulate the noise level between the interlayer and the generation of apartment houses and apartments are increasingly strict .

In addition, as the emotional quality of consumers has improved recently, the performance of NVH (noise, vibration, harshness) of automobiles, trains, and other transportation devices has become a demand of the times, and the demand of NVH related parts is rapidly increasing. Engine noise, which is generated in the engine and transmitted through the vehicle body or air, and friction noise between the wheels and the ground are representative examples of noise introduced into the interior of various transportation vehicles. In order to suppress such noise, an engine cover and a hood insulation are used. The application of sound absorption and sound insulating materials is expanding in parts requiring a large area.

There are two ways to improve the noise. One is to improve the sound absorption performance and the other way to improve the sound insulation performance. Sound absorption is the sound energy that is transmitted through the inner path of the material and is converted into heat energy and disappears. And is reflected and shielded by the shield.

Felt, sponge, polyurethane foam and the like are conventionally used as sound absorbing and sound insulating materials conventionally used. In addition, sound absorbing materials impregnated with thermoplastic resin or thermosetting resin in compressed fiber, glass fiber, rock surface, or regenerated fiber are listed . However, most of the sound absorbing materials described above have insufficient soundproofing ability, and most of the sound absorbing materials contain harmful components to the human body. Felt-type fiber materials used for various transportation interior and exterior materials are manufactured in a state in which they are physically entangled with binder fibers by using a dry nonwoven fabric manufacturing process. Such dry nonwoven fabrics are manufactured through a molding process, There is a problem that the manufacturing process is complicated and the economical efficiency is low.

In recent years, regulations on the environment-friendly and recyclability have been gradually strengthened, and the use ratio of the thermoplastic resin-based fiber-absorbing material is increasing. In order to reduce carbon dioxide, the regulation of fuel efficiency of the vehicle is gradually increasing. The improvement of fuel efficiency can be attained through the weight reduction of parts, so it is necessary to develop lightweight sound absorbing material with improved performance.

Accordingly, research and development on a sound absorbing material which is harmless to the human body and excellent in the sound absorbing function capable of effectively absorbing and reducing the noise while reducing the thickness has been actively conducted.

As a sound absorbing material that has been conventionally researched and developed, a sound absorbing material is disclosed (US Patent Publication No. 1954-433600), which is a web type in which ordinary short fibers having a diameter of 10 탆 or more are crimped to a general meltblown fiber in an amount of 10 wt% or more. Further, a two-layer automotive sound absorbing material composed of a first sound-absorbing layer and a second sound-absorbing layer having different area densities has been invented, but there is a problem that the light-weighting is insufficient and the formability is poor.

Although a three-dimensional nonwoven web made of a meltblown microfine fiber is disclosed, a three-dimensional nonwoven web has a large porosity and thus is not densely structured to have a poor durability. It is necessary to increase the thickness of the three-dimensional nonwoven web significantly, and it is difficult to manufacture the nonwoven web composed of three dimensions as described above, which increases the manufacturing cost significantly. In addition, a sound absorbing material is also disclosed, which includes staple fibers that can be fused to the meltblown fibers by heat to impart three-dimensional stability. However, such a sound absorbing material still has a problem of insufficient sound insulation performance. In addition, a sound absorbing material using a honeycomb structure having a plurality of spaces together with meltblown fibers has been disclosed. However, such a sound absorbing material is insufficient in soundproof performance and has a problem in that it is limited in its application because of lack of flexibility.

Korean Patent Publication No. 10-2014-0050219 (published April 29, 2014) Korean Patent Publication No. 10-2010-0015043 (Published on February 12, 2010)

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, and it is an object of the present invention to improve a sound absorption rate and a transmission loss by forming an air layer with a large surface area maximizing viscous loss and dissipation path of incident sound energy Which is excellent in lightweight property, water absorption property and thermal insulation property, nonwoven fabric manufactured using the same, and application product of the nonwoven fabric.

In order to solve the above-described problems, the fiber aggregate of the present invention includes polyester fibers; And hollow type sheath-core binder fibers of a hollow type for partially joining a plurality of the polyester fibers.

In one preferred embodiment of the present invention, the hollow sheath-core binder fibers may have a hollow ratio of 8% to 25%.

In one preferred embodiment of the present invention, the hollow sheath-core binder fiber comprises an elastomer resin having an intrinsic viscosity of 1.2 to 1.6 as a sheath component, and an elastomer resin having an intrinsic viscosity of 0.67 to 0.75 as a core component .

In one preferred embodiment of the present invention, the hollow sheath-core binder fiber has a melting point of 130 ° C to 190 ° C for the sheath-constituting elastomer resin, and the melting point of the elastomer resin for the core component may be 250 ° C to 280 ° C .

In one preferred embodiment of the present invention, the hollow cis-core binder fibers may have a cross-sectional area ratio of hollow, core and sheath of 1: 0.8 to 4: 1 to 5.

In one preferred embodiment of the present invention, the hollow sheath-core binder fibers may have an average fineness of 3 to 7 denier, an average fiber length of 30 to 65 mm and a crimp number of 8 to 14 / inch.

In one preferred embodiment of the present invention, the average fiber length of the hollow sheath-core binder fibers is equal to the average fiber length of the polyester fibers, or shorter than the average fiber length of the polyester fibers.

In a preferred embodiment of the present invention, the polyester fibers may have an average fineness of 5 to 10 denier, an average fiber length of 40 to 65 mm and a crimp number of 12 to 18 / inch.

In a preferred embodiment of the present invention, the polyester-based fiber includes a circular cross-section fiber; Elliptical cross-section fibers; And polymorphic cross-section fibers satisfying the following relational expression (1); And the like.

[Relation 1]

In the relational expression 1, A is the fiber cross-sectional area (mu m ² ) and P is the length (mu m) around the fiber cross-section.

In one preferred embodiment of the present invention, the polymorphic cross-section fiber may have at least one cross-sectional shape selected from a hexagonal star shape, a three-rod flat shape, a six-leaf shape, and an eight-leaf shape.

In one preferred embodiment of the present invention, the polyester fiber has an elongation of 30 to 50%, and the hollow cis-core binder fiber may have an elongation of 70 to 90%.

Another object of the present invention relates to a nonwoven fabric comprising the above-described various types of fibrous aggregates.

As a preferred embodiment of the present invention, the nonwoven fabric may have an average area density of 800 to 1,570 g / m ² when the thickness of the nonwoven fabric is 20 mm.

In a preferred embodiment of the present invention, the nonwoven fabric may have a tensile strength of 180 to 320 MPa when the nonwoven fabric has a thickness of 20 mm and an average area density of 1,520 g / m ² .

According to one preferred embodiment of the present invention, the nonwoven fabric has a thickness of 20 mm and an average surface density of 1,520 g / m < ² > The absorption coefficient is 0.55 to 0.68, and the absorption coefficient at 2,000 Hz is 0.60 to 0.75.

In one preferred embodiment of the present invention, the nonwoven fabric has a thickness of 20 mm and an average area density of 1,520 g / m ² , and the absorption coefficient is measured at 3,150 Hz according to the ISO cabin method of R 354 Is 0.67 to 0.80, and the absorption coefficient at 5,000 Hz may be 0.80 to 0.95.

In a preferred embodiment of the present invention, the nonwoven fabric when the nonwoven fabric is 20 ㎜ and an average area density 1,520 g / m ² in thickness, and the at 1,000 Hz the transmission loss 19 ~ 25 dB, the transmission loss is 22 ~ 28 dB at 2,000 Hz , The transmission loss is 31 to 40 dB at 3,150 Hz, and the transmission loss is 37 to 46 dB at 5,000 Hz.

Another object of the present invention is to provide a method for producing the nonwoven fabric, comprising the steps of: preparing each of a polyester fiber and a hollow cis-core binder fiber; A second step of producing a fiber aggregate in which the polyester fiber and the hollow sheath-core binder fiber are mixed; a third step of entangling the fiber aggregate by needle punching; And a fourth step of converting the entangled fibrous aggregate into a nonwoven fabric by performing a heat bonding process.

It is still another object of the present invention to provide a sound absorbing material, a sanitary material and / or a heat insulating material using the fibrous aggregate and / or the nonwoven fabric as an application product of the fibrous aggregate and / or the nonwoven fabric.

As a preferred embodiment of the present invention, the sound absorbing material may be applied to interior and exterior materials of a transporting machine, a refrigerator, an air conditioner or the like, a sound absorbing material of an electric appliance, or a sound absorbing material for construction.

The nonwoven fabric of the present invention provides a nonwoven fabric excellent in light weight and superior in mechanical properties such as tensile strength, elastic recovery rate and rebound resilience, as well as excellent sound absorption property and water absorption property and heat retention property as compared with conventional nonwoven fabric for sound absorbing material To a fibrous aggregate.

1 is an optical microscope photograph of the hollow cis-core binder fiber prepared in Preparation Example 1. Fig.
Fig. 2 is an electron micrograph of the hollow cis-core binder fiber prepared in Preparation Example 1. Fig.

Hereinafter, the present invention will be described in more detail.

The fibrous aggregate of the present invention relates to a fibrous aggregate obtained by partially bonding a plurality of polyester fibers with hollow cis-core binder fibers and a nonwoven fabric produced using the same.

The nonwoven fabric may be produced by a general method known in the art using the fibrous aggregate. For example, the nonwoven fabric may be prepared by a first step of preparing each of polyester fiber and hollow cis-core binder fiber; A second step of producing a fiber aggregate in which the polyester fiber and the hollow sheath-core binder fiber are mixed; a third step of entangling the fiber aggregate by needle punching; And a fourth step of converting the entangled fibrous aggregate into a nonwoven fabric by performing a heat bonding process.

The method may further include a fifth step of compressing the nonwoven fabric in four stages, and may further include a sixth step of molding the nonwoven fabric in four stages or the compressed nonwoven fabric in five stages.

The polyester fibers in the first stage are preferably polyester fibers having an average fineness of 5 to 10 denier, an average fiber length of 40 to 65 mm and a crimp number of 12 to 18 / inch, preferably an average fineness of 5.0 to 8.0, Polyester fibers having a fiber length of 45 to 62 mm and a crimp number of 12 to 16 fibers / inch are preferably used. If the average fineness of the polyester fiber is less than 5 denier, there may be a problem that the workability of the nonwoven fabric deteriorates and the thickness decreases. If the average fineness exceeds 10 denier, the number of fibers per unit weight decreases, There is a possibility that the sound absorbing performance of the nonwoven fabric is deteriorated.

If the average fiber length of the polyester fibers is less than 40 mm, the gap between the fibers may be widened to cause a problem in formation of the fiber aggregate, and the porosity may be increased to deteriorate the sound absorption performance and the insulation performance. If the average fiber length exceeds 65 mm, portions where the polyester fibers are aggregated are generated, and the gap between the fibers becomes narrow, so that the sound absorption performance and the heat insulation performance may be deteriorated.

The polyester fibers in the first stage are fibers having an elongation of 30 to 50%, and the cross-section fibers; Elliptical cross-section fibers; And polymorphic cross-section fibers satisfying the following relational expression (1); And the like.

[Relation 1]

의

값이 1.5 이상을 만족하는 것으로, 기존의 섬유구조체 흡음재에 사용되는 섬유에 비하여 넓은 표면적이 확보되고 흡음률 및 투과 손실을 향상시킬 수 있다. 값이 1.5 미만일 경우 섬유 표면적이 작아 효과적으로 흡음 성능을 구현하기 위해서는 많은 양의 섬유가 필요하여 경량화 설계가 불가능한 문제점이 있다. 그리고,

값이 클수록 섬유 표면적이 넓은 것을 뜻하므로, 보다 바람직하게는 본 발명에서 사용되는 다형단면섬유는 상기 값이 1.8 이상일 수 있으며, 더욱 바람직하게는 1.8 ~ 3.0 일 수 있다. 그러나, 다형 단면섬유의 값이 3.0을 초과할 경우 구금 제작 비용 증가, 냉각 효율 향상 관련 설비 교체, 고화속도 개선을 위한 고분자 개질, 생산성 저하 등으로 인해 결과적으로 제조 비용 상승을 초래하는 문제가 발생할 수 있다.The polymorphic cross-

of

Value satisfies 1.5 or more, a large surface area can be secured as compared with a fiber used in a conventional fiber structure sound absorbing material, and sound absorption rate and transmission loss can be improved. When the value is less than 1.5, a fiber surface area is small, and a large amount of fibers are required to effectively realize the sound absorption performance, which makes it impossible to design a light weight. And,

The larger the value, the larger the surface area of the fiber. More preferably, the value of the polymorphic cross-section fiber used in the present invention may be 1.8 or more, more preferably 1.8 to 3.0. However, when the value of the polymorphic cross-section fiber exceeds 3.0, there is a problem that the manufacturing cost is increased as a result of the increase in the cost of cement manufacturing, the replacement of the related facilities for improving the cooling efficiency, the modification of the polymer for improving the solidification rate, have.

The polymorphic cross-section fiber may be a hexagonal star shape, a three-rod flattened shape, a six-leaf shape, or an eight-leaf shape,

Further, the polymorphic cross-section fibers may have an L / W value of 2 to 3. L is the Length abbreviation value of the length of the fiber in the longitudinal direction, and W is the Abbreviation of Length Width in the transverse direction connecting the vertex and the vertex. Specifically, in the case of the 8-leaf polygonal cross-section fiber cross section, when the lengthwise direction is referred to as the longitudinal direction, the length is denoted by L and the distance from the vertex to the vertex is denoted by W in the three short-length shapes. Further, the polymorphic cross-section fibers may more preferably have 6 to 8 vertexes. However, the number of the L / W or the number of vertices is not particularly limited, and it is preferable that the fiber is a polymodal cross-section fiber having a value of 1.5 or more.

The polyester fibers in the first stage are preferably made of one or more selected from among polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT) In terms of bonding property and bonding property.

The hollow cis-core binder fibers of the first stage will be described as follows.

Wherein the binder fiber is a hollow fiber and has a hollow ratio of 8% to 30%, preferably 10% or less, and the core yarn is a high melting point elastomer and the sheath is a low melting point elastomer. To 25%, and more preferably from 10% to 20%. If the void ratio of the binder fiber is less than 8%, the binder fiber may be separated from the lightweight side, resulting in deterioration in thermal insulation and sound absorption. If the hollow fiber ratio is more than 30%, the glass fiber is inferior in lightness, sound absorption, However, there may be a problem that mechanical properties are deteriorated.

Wherein the high melting point elastomer resin comprises a mixture comprising terephthalic acid and isophthalic acid in a molar ratio of 86: 90: 10 to 14, preferably 87: 88: 12 to 13; And diol at a molar ratio of 1: 0.95 to 1, preferably 1: 0.97 to 1 mol of the mixture and the diol. At this time, it is appropriate to polymerize terephthalic acid and isophthalic acid at the above-mentioned molar ratio in view of securing a high melting point and an appropriate intrinsic viscosity.

The high melting point elastomer resin thus produced has a melting point of 250 to 280 DEG C and an intrinsic viscosity (IV) of 0.67 to 0.75, preferably a melting point of 255 to 270 DEG C and an intrinsic viscosity (IV) of 0.67 to 0.70 have.

Also, the low melting point elastomer resin is a mixture of terephthalic acid and isophthalic acid in a molar ratio of 70: 80: 20 to 30, preferably 72: 78: 22 to 28; And diol at a molar ratio of 1: 0.95 to 1, preferably 1: 0.97 to 1 mol of the mixture and the diol.

The diol used in the preparation of the low melting point elastomer resin may be 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,4-butanediol and poly (tetramethylene ether) glycol, and preferably 1,4-butanediol and poly (tetramethylene ether) glycol are used in an amount of 90 to 95 : 5 to 10 molar ratio.

The low melting point elastomer resin prepared by polymerization in this way has a melting point of 130 ° C to 190 ° C and an intrinsic viscosity (IV) of 1.2 to 1.6, preferably a melting point of 140 ° C to 175 ° C and an intrinsic viscosity (IV) of 1.3 to 1.5 have.

The hollow sheath-core binder fibers may be prepared by co-spinning a high-melting-point elastomer resin constituting the core and a low-melting-point elastomer resin constituting the sheath with a hollow composite spinneret, and then stretching and heat- have.

The composite spinning is carried out at a spinning temperature of 260 to 290 DEG C and a spinning speed of 800 to 1,200 m / min, preferably a spinning temperature of 270 to 280 DEG C and a spinning speed of 900 to 1,150 m / min.

The composite yarn may have a cross-sectional area ratio of the hollow fiber, core and sheath of 1: 0.8 to 4: 1 to 5, preferably 1: 1.5 to 2.5: 2.0 to 4, more preferably 1: Sectional area ratio of 1.8 to 2.5: 2.0 to 3.6, and is advantageous in securing a high sound-absorbing property while ensuring high tensile strength, elastic recovery and rebound resilience.

If the spinning temperature is less than 260 캜, there may be a problem that the spinning workability is poor, and if the spinning temperature is higher than 290 캜, binder fibers having an uneven hollow interior may be formed. If the winding speed is less than 800 m / min, productivity and fiber properties may deteriorate. If the winding speed exceeds 1,200 m / min, the fiber elongation decreases and the laminated form of the undrawn yarn is poor. There is a problem that the yield is lowered.

The stretching may be performed by a conventional method used in the art. Preferably, the fiber is stretched by 2.5 to 4 times, preferably 3.0 to 3.5 times at 75 ° C to 85 ° C Can be performed. If the stretching ratio is less than 2.5 times, an increase in elongation may cause problems in workability in the nonwoven fabric process. If the stretching ratio exceeds 4.0 times, there may be a problem that the yield is lowered due to occurrence of trimming and roller winding in the fiber stretching process.

The heat treatment is a step of thermally fixing the stretched fibers, and a general method used in the art can be used. For example, the stretched fibers are put into an oven and then heated at a temperature of 130 ° C to 150 ° C , Preferably at 135 ° C to 145 ° C for 10 to 30 minutes. If the heat treatment temperature is less than 130 캜, the fiber shrinkage ratio may not be controlled. If the heat treatment temperature is more than 150 캜, the fibers may become hard and the crystal may be excessively increased during the nonwoven fabric processing due to shrinkage, It is preferable to perform the heat treatment under the temperature.

The hollow cis-core binder fibers produced under the above conditions have an average fineness of 3 to 7 denier, an average fiber length of 30 to 65 mm and a crimp number of 8 to 14 fibers / inch, preferably 3.0 to 4.5 denier, It has a crimp number of 10.5 ~ 13.2 / inch, and the average fiber length is preferably the same or short as the fiber length of the polyester fiber.

At this time, if the average fineness of the hollow cis-core binder fibers is less than 3 deniers, there may be a problem that defective nonwoven fabric workability and physical properties are lowered, and when the denier is more than 7 deniers, the adhesive area is decreased, Can be. If the average fiber length is less than 30 mm, there may be a problem that the properties of the nonwoven fabric deteriorate due to a decrease in the interfiber bonding force. If the average fiber length is longer than 65 mm or the polyester fiber, the intertwine twist increases, There may be problems that occur. If the number of crimps is less than 8 / inch, there may be a problem that the binding force is lowered. If the number of crimps exceeds 14 / inch, the nonwoven fabric crystals may increase.

The hollow sheath-core binder fibers have an elongation of 70% to 90% and a strength of 2.5 to 3.8 g / d, preferably 2.7 to 3.6 g / d.

In the method for producing a nonwoven fabric of the present invention, at the time of producing the fibrous aggregate of two stages, the mixing is carried out by mixing the polyester fibers and the hollow cis-core binder fibers in a weight ratio of 65 to 80:20 to 35, If the hollow cis-core binder fibers are less than 20 parts by weight, the bonding strength between the polyester fibers may be lowered so that the weight of the nonwoven fabric may be lowered. There may be a problem that the mechanical properties are poor. When the weight ratio of the nonwoven fabric is more than 35 parts by weight, it may be advantageous in view of the mechanical properties of the nonwoven fabric, but the voids in the nonwoven fabric may be reduced to deteriorate physical properties such as sound absorption and heat insulation. It is good to do.

Then, the fibrous aggregate is entangled with the fibrous aggregates by a general method in the art, preferably needle punching is performed to produce entangled fibrous aggregate, and then the nonwoven fabric is manufactured by performing a heat-bonding process. At this time, the heat bonding step may be performed at 120 ° C to 150 ° C and 300 to 500 kgf / cm ² .

When the thickness of the nonwoven fabric of the present invention is 20 mm, the average area density is 800 to 1,570 g / m ² , preferably 800 to 1,520 g / m ² , and more preferably 950 to 1,520 g / m ² .

The nonwoven fabric of the present invention may have a tensile strength of 180 to 320 MPa, preferably 200 to 300 MPa, and more preferably 220 to 300 MPa when the thickness is 20 mm and the average surface density is 1,520 g / m ² .

The nonwoven fabric of the present invention has an elastic recovery rate of 50 to 72%, preferably 52 to 70% when measured according to the following formula (1) when the thickness is 20 mm and the average area density is 1,520 g / m ² .

[Equation 1]

Elastic recovery rate (%) = {[20- (L-10) / 20]} x 100 (%)

In the equation (1), L is a dumbbell-shaped sample having a thickness of 2 mm and a length of 10 cm, stretched 200% at a rate of 200% / min, Quot; refers to the elongated length after it is made.

Moreover, the the present non-woven fabric of the invention, and an average area density 20 ㎜ thickness of 1,520 g / m as ^2, a 55-85% impact resilience measured in accordance with JIS K-6301, preferably 60 to 85%, more preferably And 62 to 82% of the total.

The nonwoven fabric of the present invention has a thickness of 20 mm and an average area density of 1,520 g / m ² , and has an absorption coefficient of 0.55 or more, preferably 0.55 or more, at 1,000 Hz in the measurement of sound absorption coefficient based on the alpha cabin method of ISO R 354, 0.68, and a sound absorption coefficient of 0.60 or more, preferably 0.60 to 0.75 at 2,000 Hz. Further, the absorption coefficient may be 0.67 or more, preferably 0.67 to 0.80 at 3,150 Hz, and the absorption coefficient may be 0.80 or more, preferably 0.80 to 0.95 at a high frequency of 5,000 Hz.

In addition, the nonwoven fabric of the present invention when 20 ㎜ and an average area density 1,520 g / m ² in thickness ,, and 1,000 Hz in the transmission loss is 19 ~ 25dB, and the transmission loss of 22 ~ 28 dB at 2,000 Hz, the transmission loss at 3,150 Hz Has a 31 to 40 dB and a transmission loss of 37 to 46 dB at 5,000 Hz.

The nonwoven fabric of the present invention may further comprise a cover layer (or a supporting layer) serving as a cover on one surface, both surfaces, or an outer surface of the nonwoven fabric.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples should not be construed as limiting the scope of the present invention, and should be construed to facilitate understanding of the present invention.

[ Example ]

Preparation Example  One : Sys for Low melting point  Preparation of elastomer resin

75 mol% of terephthalic acid and 25 mol% of isophthalic acid as an acid component were mixed. Then, the mixture 1 was mixed with 92 mol% of 1,4-butanediol and 8.0 mol% of poly (tetramethylene ether) glycol as a diol component The mixture 1 (acid component) and the mixture 2 (diol component) were mixed at a molar ratio of 1: 1 and the polymerization reaction was carried out to prepare a low melting point elastomer resin, Respectively.

Preparation Example  2: for core High melting point  Preparation of elastomer resin

89 mol% of terephthalic acid and 11 mol% of isophthalic acid as an acid component were mixed, and 100 mol% of 1,3-propanediol was used as the diol component and the mixture (acid component) and the diol component Were mixed at a molar ratio of 1: 1, and polymerization reaction was carried out to prepare a high melting point elastomer resin. Properties of the high melting point elastomer resin are shown in Table 1 below.

division Melting point Intrinsic viscosity (IV) Preparation Example 1 (Cis) 150 ℃ 1.40 Preparation Example 2 (Core) 260 ℃ 0.68

Preparation Example  3-1: Hollow type Cis - Preparation of core binder fibers

The low melting point elastomer resin of Preparation Example 1 and the high melting point elastomer resin of Preparation Example 2 were combined and spinned at a spinning temperature of 275 DEG C and a winding speed of 1,000 m / min using a hollow composite spinneret to produce hollow cis-core fibers .

Next, the composite spinning short cis-core filaments were subjected to a drawing at 3.3 times at 77 캜.

Next, the stretched staple fibers were put into an oven and subjected to a final heat treatment at 140 ° C. to obtain an average fineness of 4 denier, an average fiber length of 51 mm, a strength of 3.0 g / d, an elongation of 80%, a number of crimps of 12 / (Hollow fiber, core and sheath cross section ratio of 1: 1.9: 2.1) having a circular cross section having a circular cross section of 20% was prepared.

1 and 2 show cross-sectional photographs of the produced hollow cis-core binder fibers.

Preparation Example  3-2 ~ Preparation Example  3-3

Core hollow fibers were prepared in the same manner as in Preparation Example 3-1 except that the hollow ratio of the hollow composite spinneret was controlled so that the cross sectional area ratio of the hollow, 2 were prepared in the same manner as in Preparation Examples 3-2 to 3-3, respectively.

Example of comparison preparation  One

The hollow cis-core binder fibers were prepared in the same manner as in Preparation Example 3-1 and Preparation Example 3-1 except that the hollow composite spinneret was used instead of the hollow composite spinneret, Hollow body sheath-core binder fibers having physical properties and cross-sectional area ratios were prepared.

Example of comparison preparation  2 ~ Example of comparison preparation  5

Core hollow fibers were prepared in the same manner as in Preparation Example 3-1 except that the hollow ratio of the hollow composite spinneret was controlled so that the cross sectional area ratio of the hollow, Core hollow fibers having the same physical properties and cross-sectional area ratios as Comparative Preparation Examples 2 to 3 were prepared.

division Sectional area ratio
(Hollow: core: sheath) Average
Fineness
(Denier) Average
Fiber sheet
(Mm) Crimp
Number
(Dogs / inches) burglar
(g / d) Shindo
(%) Preparation Example 3-1 1: 1.9: 2.1
(Hollow ratio 20%) 4 51 12 3.0 80 Preparation Example 3-2 1: 4: 5
(Hollow ratio 10%) 4 51 12 3.6 73 Preparation Example 3-3 1: 2.53: 3.13
(Hollow ratio 15%) 4 51 12 3.2 76 Example of comparison preparation
One 0: 1: 1.2
(Hollow ratio 0%) 4 51 12 4.6 64 Example of comparison preparation
2 1: 8: 9
(Hollow ratio 5%) 4 51 12 4.0 70 Example of comparison preparation
3 1: 0.71: 1.14
(Hollow ratio 35%) 4 51 12 2.2 62

Example  1: Fabrication of fiber aggregate and nonwoven fabric

7 denier, 51 mm, a strength of 4.1 g / d, an elongation of 40% and a crimp number of 14.2 pcs / inch, and a hollow cis-core binder fiber of Preparation Example 3-1 in a ratio of 7: 3 And the mixture was physically entangled in a needle punching process by adjusting its weight constantly. Thereafter, a heat bonding process was performed under the conditions of 135 ° C and 420 kgf / cm ² to form a fiber bundle having a thickness of 20 mm, A nonwoven fabric having a density of 1,520 g / m ² was produced.

Example  2

=2.5)인 다형단면 폴리에스테르 섬유를 사용하여 두께 20mm, 평균면밀도 1,566 g/m²의 부직포를 제조하였다.A nonwoven fabric was produced under the same conditions as in Example 1 except that the polyester fiber having a circular cross section was 6.5 denier, 59 mm, an intensity of 5.8 g / d, an elongation of 40%, an 8-

= 2.5) was used to prepare a nonwoven fabric having a thickness of 20 mm and an average area density of 1,566 g / m ² .

Example  3

=1.93)인 다형단면 폴리에스테르 섬유를 사용하여 두께 20mm, 평균면밀도 1,558 g/m²의 부직포를 제조하였다.A nonwoven fabric was produced under the same conditions as in Example 1 except that 6.5 denier, 59 mm, a strength of 5.8 g / d, an elongation of 40% and a crimp number of 14.2 / inch were used instead of the circular polyester fiber having a circular cross section

= 1.93) was used to prepare a nonwoven fabric having a thickness of 20 mm and an average area density of 1,558 g / m ² .

Example 4 ~ Example  5 and Comparative Example  1 ~ Comparative Example  6

A nonwoven fabric was produced under the same conditions as in Example 1 except that the binder fibers prepared in Preparation Examples 3-2 to 3-3 and Comparative Preparation Examples 1 to 5 were used in place of Preparation Example 3-1, Respectively.

division Polyester
fiber Hollow type
Sheath Core Binder Fiber Non-woven
thickness Average area density
(g / m ² ) Example 1 circle Preparation Example 3-1 20 탆 1,520 g / m < ² > Example 2

=2.5)8 leaf type
(

= 2.5) Preparation Example 3-1 20 탆 1,566 g / m ² Example 3 6 leaf type
(

= 1.93) Preparation Example 3-1 20 탆 1,558 g / m ² Example 4 circle Preparation Example 3-2 20 탆 1,470 g / m < ² > Example 5 circle Preparation Example 3-3 20 탆 1,490 g / m < ² > Comparative Example 1 circle Comparative Preparation Example 1 20 탆 1,640 g / m ² Comparative Example 2 circle Comparative Preparation Example 2 20 탆 1,590 g / m < ² > Comparative Example 3 circle Comparative Preparation Example 3 20 탆 1,380 g / m ² Comparative Example 4 8 leaf type
(

= 2.5) Comparative Preparation Example 1 20 탆 1,600 g / m ²

Experimental Example  1: tensile strength, Elastic recovery rate  And rebound modulus

The tensile strength, elastic recovery rate and rebound resilience of each of the nonwoven fabrics prepared in Examples and Comparative Examples were measured by the following methods, and the results are shown in Table 4 below.

(1) Tensile Strength (Load at Tensile Strength, MPa ) Measure

The tensile strength of the sample was measured ten times under the conditions of a tensile speed of 500 mm / min, a Road-Cell of 2 kN and a Grib of 5 kN, and the tensile strength was determined as an average value thereof.

(2) Elastic recovery rate  Measure

The elastic recovery rate was measured by using Instron to measure a sample having a thickness of 2 mm and a length of 10 cm in a dumbbell shape at a rate of 200% And was found by the following formula (1).

[Equation 1]

Elastic recovery rate (%) = {[20- (L-10) / 20]} x 100 (%)

In Equation (1), L means an elongated length.

(3) Ball Rebound Measurement

The height of the rebound was measured by dropping iron beads on a test piece at a constant height. (JIS K-6301, unit:%) The test specimens were made with a side length of 50 mm or more and a thickness of 50 mm or more and a steel ball with a weight of 16 g and a diameter of 16 mm was dropped on a test piece at a height of 500 mm, After the measurement, the rebound value was measured at least three times in succession within one minute in each of the three test pieces, and the median value was determined as the rebound resilience (%).

division The tensile strength( MPa ) Elastic recovery rate ( % ) Rebound modulus % ) Example 1 227 67 73 Example 2 205 69 82 Example 3 212 72 84 Example 4 246 61 68 Example 5 230 69 75 Comparative Example 1 302 66 75 Comparative Example 2 271 55 62 Comparative Example 3 198 51 53 Comparative Example 4 221 70 73

As a result of the test results of Table 4, in the case of Examples 1 to 4 and Comparative Example 1 using hollow fiber without binder, the overall mechanical properties were excellent.

However, in the case of Comparative Example 2 in which the hollow ratio was 5%, the tensile strength was excellent, but the rebound resilience was significantly lower than that in Examples.

In Comparative Example 3 in which the hollow ratio exceeded 30%, the tensile strength, the elastic recovery rate and the rebound resilience were both lowered as compared with Example 1, indicating that the hollow was too large to secure mechanical properties It is believed that the core and sheath parts serving as support cements are too small.

In addition, in the case of Comparative Example 4 produced using polyester fibers having a modified cross-section and hollow fiber without hollow, the overall mechanical properties were excellent.

Experimental Example  2: Measurement of absorption coefficient and transmission loss (dB) by frequency (Hz)

Each of the nonwoven fabrics prepared in Examples 1 to 4 and Comparative Examples 1 and 4 was cut to a width of 1.2 m and a length of 1.0 m to prepare specimens. The specimens were then subjected to frequency-dependent (Hz) And the average measurement results thereof are shown in Table 5 below.

 (1) Sound absorption coefficient measurement by frequency

For the measurement of the sound absorption coefficient, three samples were prepared for each test piece applicable to the ISO R 354, Alpha Cabin method, and the sound absorption coefficient was measured after leaving for 30 minutes at the external temperature of 0 ° C and 25 ° C, and the average value of the measured sound absorption coefficient is shown in Table 5 . Measuring equipment Instron was used for ^R.

(3) Measurement of transmission loss (dB) by frequency

To measure the sound insulation effect, 3 pieces of each specimen applicable to APAMAT-Ⅱ, which is a permeation loss coefficient evaluation equipment, were manufactured, and the insertion loss was measured. The average value of the measured insertion loss is shown in Table 5.

division Frequency (Hz) Sound absorption coefficient Frequency (Hz) Transmission Loss (dB) 1,000
Hz 2,000
Hz 3,150
Hz 5,000
Hz 1,000
Hz 2,000
Hz 3,150
Hz 5,000
Hz Example 1 0.64 0.71 0.75 0.92 23 24 34 42 Example 2 0.65 0.71 0.78 0.94 24 26 36 43 Example 3 0.65 0.74 0.80 0.95 25 28 39 45 Example 4 0.52 0.61 0.69 0.84 19 23 32 39 Example 5 0.60 0.63 0.72 0.88 22 25 32 41 Comparative Example 1 0.50 0.59 0.70 0.78 18 21 30 39 Comparative Example 4 0.48 0.53 0.62 0.76 19 23 25 37

As shown in Table 5, in Examples 1 to 5, a high sound absorption coefficient and a transmission loss were shown.

On the other hand, the comparative example 1 and the comparative example 4 showed a very low sound absorption coefficient and a transmission loss as compared with the example 1.

It can be seen from the above Examples and Experimental Examples that the nonwoven fabric of the present invention has excellent sound absorption and sound insulation capabilities as well as high frequency band and low frequency band, and has excellent mechanical properties, and furthermore, .

The nonwoven fabric of the present invention can be applied to products such as a sound absorbing material used for interior and exterior materials of transportation equipment, electrical products and electronic products, a heat insulating material such as bedding materials, and a water absorbing material for sanitary materials.

Claims (19)

Polyester fibers having an average fineness of 5 to 10 denier, an average fiber length of 40 to 65 mm and a crimp number of 12 to 18 / inch; And a hollow cis-core binder fiber having a hollow ratio of 8 to 30%, the fibers being partially bonded to a plurality of the polyester fibers,
Wherein the hollow sheath-core binder fiber comprises an elastomer resin having an intrinsic viscosity of 1.20 to 1.60 as a sheath component, and an elastomeric resin having an intrinsic viscosity of 0.67 to 0.75 as a core component, wherein the hollow sheath- core binder fiber is excellent in sound absorption, Fiber aggregate.
The thermosetting resin composition according to claim 1, wherein the sheath elastomer resin has a melting point of 130 ° C to 190 ° C, and the elastomer resin of the core component has a melting point of 250 ° C to 280 ° C. aggregate.
The fiber aggregate according to claim 1, wherein the hollow cis-core binder fibers have a cross-sectional area ratio of 1: 0.8 to 4: 1 to 5: hollow, core and sheath.
The hollow sheath-core binder fiber according to claim 1, wherein the hollow sheath-core binder fibers have an average fineness of 3 to 7 denier, an average fiber length of 30 to 65 mm and a crimp number of 8 to 14 / inch. Excellent fiber aggregate.
5. The polyester fiber according to claim 4, wherein the average fiber length of the hollow sheath-core binder fibers is equal to or smaller than the average fiber length of the polyester fibers, This excellent fiber aggregate.
The fiber aggregate according to claim 1, wherein the polyester fiber has an elongation of 30 to 50% and an elongation of the hollow cis-core binder fiber is 70 to 90%. .
The polyester fiber according to claim 1, wherein the polyester-
Circular section fibers; Elliptical cross-section fibers; And polymorphic cross-section fibers satisfying the following relational expression (1); A fiber aggregate having excellent sound absorption properties, water absorption properties, and heat retention characteristics;
[Relation 1]

In the relational expression 1, A is the fiber cross-sectional area (mu m ² ) and P is the length (mu m) around the fiber cross-section.
The fiber aggregate according to claim 7, wherein the polymorphic cross-section fibers have at least one cross-sectional shape selected from hexagonal star shape, three-rod flat shape, six-leaf shape and eight-leaf shape.
A nonwoven fabric comprising the fibrous aggregate of any one of claims 1 to 8.
The nonwoven fabric according to claim 9, wherein the average area density is 800 to 1,570 g / m ² when the thickness of the nonwoven fabric is 20 mm.
The nonwoven fabric according to claim 10, wherein when the nonwoven fabric has a thickness of 20 mm and an average surface density of 1,520 g / m ² , the tensile strength is 180 to 320 MPa,
Characterized in that the sound absorption coefficient is from 0.55 to 0.68 at 1,000 Hz and the sound absorption coefficient is from 0.60 to 0.75 at 2,000 Hz in the measurement of the sound absorption coefficient according to the alpha cabin method of ISO R 354.
The absorbent article according to claim 10, wherein when the nonwoven fabric has a thickness of 20 mm and an average surface density of 1,520 g / m ² , the absorption coefficient is measured at 3,150 Hz in accordance with the ISO cabinet method of R 354, from 0.67 to 0.80 And a sound absorption coefficient of 0.80 to 0.95 at 5,000 Hz.
11. The method of claim 10, wherein, when the nonwoven fabric is 20 ㎜ and an average area density 1,520 g / m ² in thickness, and from 1,000 Hz the transmission loss is 19 ~ 25 dB, a transmission loss is 22 ~ 28 dB at 2,000 Hz, the transmission at 3,150 Hz Wherein the loss is 31 to 40 dB and the transmission loss at 5, 000 Hz is 37 to 46 dB.
The method according to claim 10, wherein the elastic recovery rate is 50 to 72% when measured according to the following formula (1)
A nonwoven fabric having a rebound resilience of 55 to 85% as measured according to JIS K-6301;
[Equation 1]
Elastic recovery rate (%) = {[20- (L-10) / 20]} x 100 (%)
In the equation (1), L is a dumbbell-shaped sample having a thickness of 2 mm and a length of 10 cm, stretched 200% at a rate of 200% / min, Quot; refers to the elongated length after it is made.
A sound absorbing material comprising the nonwoven fabric of claim 10.
A sanitary article comprising the nonwoven fabric of claim 10.
A heat insulating material comprising the nonwoven fabric of claim 10.
A first step of preparing each of the polyester fiber and the hollow cis-core binder fiber;
Wherein the polyester fiber and the hollow sheath-core binder fiber are mixed to produce a fiber aggregate.
A third step of needle punching and entangling the fiber aggregate; And
And a fourth step of converting the entangled fibrous aggregate into a nonwoven fabric by performing a heat bonding process.
19. The absorbent article of claim 18, further comprising: polyester fibers having an average fineness of 5 to 10 denier, an average fiber length of 40 to 65 mm and a crimp number of 12 to 18 / inch; And a hollow cis-core binder fiber having a hollow ratio of 8 to 25%, the fibers being partially bonded to a plurality of the polyester fibers,
Wherein the hollow sheath-core binder fiber comprises an elastomer resin having an intrinsic viscosity of 1.20 to 1.60 as a sheath component and an elastomeric resin having an intrinsic viscosity of 0.67 to 0.75 as a core component.

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