KR100832350B1 - Noise absorbent carpet for vehicle - Google Patents

Abstract

A noise absorbent carpet for a vehicle is provided to absorb effectively noise of the vehicle by using a carpet layer, two non-woven fabric layers, and an adhesive layer made of a thermoplastic non-woven fabric or a mixture of thermoplastics and inorganic fillers. A noise absorbent carpet(1) for a vehicle includes a carpet layer(11), a first non-woven fabric layer(13), and a second non-woven fabric layer(14). The carpet layer is formed by kneading a yarn selected from a group consisting of polyester, nylon, polypropylene, cotton, hemp, and wooly hair onto a sheet of non-woven fabric foam paper made of polypropylene or polyester. The carpet layer has a bottom surface which is back-coated by at least one material selected from a group consisting of ethylene vinyl acetate, styrene butadiene rubber, natural latex and polyethylene. The first non-woven fabric layer is made of at least one material selected from a group consisting of polyester, polypropylene, and polyamide. The second non-woven fabric layer is made of at least one material selected from a group consisting of polyester, polyolefine, polyethylene and polystyrene. The first non-woven fabric layer has a wound reduction coefficient different from that of the second non-woven fabric layer.

Description

Sound absorption carpet for car {NOISE ABSORBENT CARPET FOR VEHICLE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound absorbing carpet for automobiles, and more particularly to a sound absorbing carpet for automobiles comprising a carpet layer, a breathable adhesive layer and a nonwoven sound absorbing layer of a double structure.

Carpets are installed in automobiles to block noise and vibration from the outside.

The noise flowing into the vehicle may include noise generated by an engine while driving, noise generated by contact between a tire and a road surface, and noise generated by friction between the wind and the vehicle while driving. In order to improve such noise, a technology for improving sound insulation performance and a sound absorption performance have been developed in a vehicle, and in recent years, in order to absorb noise introduced into a vehicle rather than sound insulation that blocks external noise. Technology is being developed.

Various methods have been attempted to introduce sound absorbing performance to automotive carpets, for example, by laminating non-woven sound absorbing layers through an adhesive film on the back side of carpet dough where piles are planted on the surface side and heat-pressing them so that they are bonded and integrated. It is known.

In addition, in order to shield external noise, a method of using a separate sound insulation material is mainly used. In this case, since a heavy weight sound insulation material is used, the weight of the vehicle body increases, fuel economy deteriorates, and cost increases.

As a prior art related to automobile sound absorbing carpet, Korean Patent No. 289318 discloses a porous spring layer formed of an open-open foam layer, an air composite layer between a vehicle body and a package assembly, and an open-open fibrous layer or fiber to reduce noise of a vehicle. A kit consisting of a porous hard layer formed of a / foam composite layer is described.

Korean Patent Laid-Open Publication No. 2003-0057388 describes a carpet in which the skin material layer and the nonwoven fabric sound absorbing layer are adhesively integrated through a breathable adhesive resin layer.

Korean Patent No. 553408 describes a dual structure carpet absorber comprising a carpet, a polyethylene film layer, a second stage sound absorber and a first stage sound absorber without using a heavy layer layer.

The present inventors have further developed the sound absorbing carpet for automobiles having improved sound absorption performance by combining two nonwoven layers having different physical properties without using the heavy layer.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sound absorbing carpet for automobiles having excellent sound absorption against noise inside the vehicle and noise coming from the outside.

 In a sound absorbing carpet for automobiles comprising a carpet layer, a breathable adhesive layer and a nonwoven sound absorbing layer having a double structure, two types of nonwoven layers having different damping coefficients can be used to provide a sound absorbing carpet for a car having excellent sound absorbing performance. In particular, by using a thermoplastic nonwoven fabric having an irregular mesh structure as the adhesive layer or by using an inorganic filler in the adhesive layer, air permeability and sound absorption performance can be improved.

According to the present invention, two nonwoven layers having different damping coefficients are laminated, and a sound absorbing carpet for automobiles is manufactured by using an irregular mesh-shaped thermoplastic nonwoven fabric or powder of a thermoplastic resin and an inorganic filler mixture as an adhesive layer. When used as a mat, it can effectively absorb the noise inside and outside the car.

According to a preferred embodiment of the present invention, by tufting or needled a yarn composed of one kind selected from the group consisting of polyester, nylon, polypropylene, cotton, hemp and wool on a bubble made of polypropylene or polyester At least one selected from the group consisting of a carpet layer, polyester, polypropylene and polyamide backcoated with at least one selected from the group consisting of ethylene vinyl acetate, styrene butadiene rubber, natural latex and polyethylene A first nonwoven fabric layer formed of a microfiber nonwoven fabric, and a second nonwoven fabric layer formed of a nonwoven fabric of at least one selected from the group consisting of polyester, polyolefin, polyethylene, and polystyrene, and comprising a first nonwoven fabric layer and a second nonwoven fabric layer. Is characterized in that the noise coefficient is different.

According to another suitable embodiment of the present invention, the first nonwoven layer has a thickness of 0.1 to 5.0 mm, a surface density of 50 to 500 g / m ² , and a damping coefficient of 0.3 to 0.8, wherein the first nonwoven layer is The fiber having a single yarn fineness of 0.05 to 20 decitex is 50% by weight to 100% by weight of the total weight of the nonwoven fabric.

According to another suitable embodiment of the present invention, the second nonwoven layer is characterized by having a thickness of 0.5 to 50 mm, a surface density of 100 to 1,000 g / m ² , and a damping coefficient of 0.2 to 0.8.

According to another suitable embodiment of the present invention, at least one of the adhesive layers adhering the carpet layer, the first nonwoven fabric layer and the second nonwoven fabric layer is formed by heating and melting a thermoplastic resin having an irregular network structure.

According to another suitable embodiment of the present invention, at least one of the adhesive layers adhering the carpet layer, the first nonwoven fabric layer and the second nonwoven fabric layer is formed by pulverizing a mixture of the thermoplastic resin and the inorganic filler in powder form and then heating and melting The amount of the inorganic filler in the mixture of the thermoplastic resin and the inorganic filler is 1 to 10% by weight of the thermoplastic resin.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 is a cross-sectional view of a sound absorbing carpet 1 for a vehicle according to an embodiment of the present invention.

Referring to FIG. 1, a sound absorbing carpet for automobiles according to the present invention includes a carpet layer 11, an adhesive layer 12, a first nonwoven fabric layer 13, an adhesive layer 12, and a second nonwoven fabric layer 14. The sound absorbing carpet according to the invention can be laid on the car's mat as an auxiliary mat or it can be laid on the car body as a car's mat. The present invention provides a sound absorbing carpet for automobiles that can effectively absorb the noise inside the vehicle and the noise introduced from the outside by using a non-woven fabric layer having a dual structure having different physical properties and noise coefficient.

In the sound absorbing carpet according to the present invention, the carpet layer 11 is not particularly limited and generally known carpet fabrics may be used.

Foam paper made of polypropylene, polyester, polyester / polypropylene material or a mixture of these materials is made of synthetic fibers such as polyester fibers, nylon fibers, polypropylene fibers and acrylic fibers, or natural fibers such as hemp, cotton and wool. Tufted yarns made of fibers, or those in which various fibers or yarns are mechanically bound by a needling process or bound by an adhesive or the like can be used. The bottom surface of the carpet layer can be backcoated as needed. 50-400 g / m ² weight using ethylene vinyl acetate (EVA), styrene-butadiene rubber (SBR), natural latex, polyethylene or mixed materials Can be backcoated or omitted.

In the present invention, the adhesive layer 12 attaching the carpet layer 11 and the first nonwoven fabric layer 13 may be formed in various ways. A general industrial adhesive may be used, and may be preferably attached while laminating one thermoplastic resin selected from the group consisting of low-melting polyester, polyethylene, ethylene vinyl acetate, polypropylene and polyvinyl chloride. It can be attached by passing through the pressing roller after placing the thin nonwoven fabric or porous hot melt film form between the carpet layer and the first nonwoven layer. Alternatively, the thermoplastic resin may be applied onto the first nonwoven fabric layer in the form of powder or pellets, and then laminated by carpeting the carpet layer 11 and the first nonwoven fabric layer 13 in a molten state and passing the pressing roller.

In this case, the inorganic filler having a plate-like crystal structure such as porous silica or zeolite, or porous silica, zeolite, etc. is added to the thermoplastic resin to form a masterbatch, which is then pulverized into powder or used as a nonwoven fabric to heat the thermoplastic resin. It can improve the adhesive strength of the fusion bonding surface and improve breathability. The amount of inorganic material added is preferably 1 to 10% by weight of the thermoplastic resin. If less than 1% by weight, the effect of improving the air permeability due to the inorganic filler is lowered, when more than 10% by weight will be lowered the adhesive effect. In addition, the diameter of the pulverized powder is preferably 100 ~ 1000㎛, in this case it is possible to obtain a powder in which the thermoplastic resin and the porous inorganic filler is uniformly dispersed.

Since the porous inorganic filler has irregular surface and many fine protrusions, it acts as a kind of reinforcing material, and the surface adhesion between materials is improved, and if air gap is formed between the resin and the inorganic filler, the air permeability of the adhesive name can be expected to be improved. In addition, by using an inorganic filler such as mica having a plate-shaped crystal structure, there is an additional advantage that it is possible to reinforce the sound insulation degradation due to the absence of the sound insulating coating layer.

More preferably, the thermoplastic resin is formed into a thin nonwoven fabric having an irregular mesh structure, and is placed between the carpet layer 11 and the first nonwoven layer 13, and then the two rollers are laminated in a heat-melted state, and then the pressing roller is pressed. It can be combined by passing.

Due to the adhesive layer of the irregular mesh structure, it is possible to additionally absorb noise in the non-absorbed frequency region while passing through the nonwoven fabric layer, and the adhesive layer itself is breathable so that the sound absorbing performance of the entire carpet is not impaired.

At this time, the amount of the thermoplastic resin applied in the form of a nonwoven fabric or film or a powder or pellets used for the thermal bonding function is 50 to 300g / ㎡ is suitable. When the amount of the thermoplastic resin used is less than 50 g / m 2, sufficient adhesive strength is not exhibited. When the amount of the thermoplastic resin is used, when the amount exceeds 300 g / m 2, excessive weight of the vehicle parts becomes a problem, and the sound absorbing performance is lowered due to poor air permeability of the adhesive layer.

The first nonwoven fabric layer 13, which is a sound absorbing layer of the sound absorbing carpet for automobiles according to the present invention, is characterized in that the nonwoven fabric layer is formed of polyester, polypropylene, polyamide, or the like alone or in combination. Electrospun microfibers, polyester / polyamide split microfibers, polyester direct spun microfibers, and the like may be generally used. The microfibers may be advantageous to sound absorbing performance in an amount of 50 to 100% based on the total weight of the nonwoven fabric. The method for forming the nonwoven fabric is not particularly limited, such as a needle punch, a spunlace, a spun bond, and a known method can be used.

The first nonwoven fabric layer has a thickness of 0.1 to 5.0 mm and a surface density of 50 to 500 g / m 2. If the surface density is less than 50g / ㎡ the sound absorbing performance improvement effect is insufficient, if it exceeds 500g / ㎡ there is a problem that excessive weight of the vehicle parts is a problem and air or sound can not pass through and the sound absorbing function is poor.

In addition, the single yarn fineness of the microfine fibers in the nonwoven fabric constituting the first nonwoven fabric layer is preferably 0.05 to 20 decitex, more preferably 0.05 to 1.5 decitex. When the fineness of the nonwoven fabric constituent fibers is less than 0.05 decitex, it is difficult to absorb low frequency noise, and the cushioning property is also lowered. On the other hand, exceeding 20 decitex makes it difficult to absorb high frequency noise. The air permeability of the first nonwoven fabric layer thus prepared is 3 to 50 cm 3 / cm 2 · sec and the damping coefficient, which is a numerical value representing the sound absorption performance of the microfiber nonwoven fabric layer, is 0.3 to 0.8.

The attenuation coefficient used in the present invention is an arithmetic mean value of the sound absorption coefficients at the center frequency of 500, 1000, and 2000 Hz. The higher the coefficient, the better.

As the second nonwoven fabric layer 14 of the present invention, a nonwoven fabric made of a single or mixed fiber such as polyester, polyolefin, polyethylene, polystyrene, or the like can be used. The method for producing the second nonwoven fabric layer is not particularly limited, such as needle punch, spunlace, spunbond, or the like. The second non-woven fabric layer not only acts as a backing material for the shape-keeping function of the vehicle carpet, but also additionally improves the sound absorption performance. The single yarn fineness is 1.0 to 20 decitex and the thickness is 0.5 to 50 mm, and the surface density is 100. Nonwoven fabrics of ˜1,000 g / m 2 are suitable. If the surface density is less than 100g / ㎡ the contribution effect to the shape retention ability and sound absorption performance is low, and if it exceeds 1,000g / ㎡ excessive weight of the vehicle parts is a problem, the surface becomes too hard and the sound absorption performance is also poor. The air permeability of the second nonwoven fabric layer is 3 to 60 cm 3 / cm 2 · sec, and the damping coefficient, which is a numerical value representing sound absorption performance, is 0.2 to 0.8.

The outer side of the second nonwoven fabric layer 14 may adopt a structure in which a non-slip resin layer is laminated or integrated in order to prevent slipping with the material in contact with this portion. Alternatively, the surface of the second nonwoven layer may be slightly burned with a flame or passed through a hot roller to partially melt the surface fiber to form a rough surface texture, and may attach a positive portion of the velcro tape. Machining can be done selectively, or can be omitted.

In addition, in the nonwoven fabric manufacturing step, one surface of the second nonwoven fabric layer may be formed to have an irregular network shape to enable the slip prevention function and the sound absorption performance assistance.

The first nonwoven fabric layer 13 and the second nonwoven fabric layer 14 are bonded by an adhesive layer 12, which is the same as the method of bonding the carpet layer and the first nonwoven fabric layer. One thermoplastic resin selected from the group consisting of low melting point polyester, polyethylene, ethylene vinyl acetate, polypropylene and polyvinyl chloride is formed into a breathable thin nonwoven or porous hot melt film and placed on the second nonwoven layer. After laminating with the first nonwoven fabric layer, it can be adhered by passing the pressing roller.

In another embodiment, the thermoplastic resin is applied onto the second nonwoven layer in the form of powder or pellets, and then the first nonwoven fabric layer 12 and the second nonwoven fabric layer 13 are laminated in a state of being heated and melted and passed through a pressing roller. I can attach it. Since the adhesive layer 12 formed by the above method has air permeability, the sound absorbing performance of the carpet is not impaired.

In this case, the inorganic filler having a plate-like crystal structure such as porous silica or zeolite, or porous silica, zeolite, etc. is added to the thermoplastic resin to form a masterbatch, which is then pulverized into powder or used as a nonwoven fabric to heat the thermoplastic resin. It can improve the adhesive strength of the fusion bonding surface and improve breathability. The amount of inorganic material added is preferably 1 to 10% by weight of the thermoplastic resin. If less than 1% by weight, the effect of improving the air permeability due to the inorganic filler is lowered, when more than 10% by weight will be lowered the adhesive effect. In addition, the diameter of the pulverized powder is preferably 100 ~ 1000㎛, in this case it is possible to obtain a powder in which the thermoplastic resin and the porous inorganic filler is uniformly dispersed.

Since the porous inorganic filler has irregular surface and many fine protrusions, it acts as a kind of reinforcing material, and the surface adhesion between materials is improved, and if air gap is formed between the resin and the inorganic filler, the air permeability of the adhesive name can be expected to be improved. In addition, by using an inorganic filler such as mica having a plate-shaped crystal structure, there is an additional advantage that it is possible to reinforce the sound insulation degradation due to the absence of the sound insulating coating layer.

More preferably, the thermoplastic resin is formed into a thin nonwoven fabric having an irregular mesh structure and placed between the first nonwoven fabric layer 13 and the second nonwoven fabric layer 14, and then the two layers are laminated in a hot melt state. It can be combined by passing the pressing roller.

Any one of the two adhesive layers may be formed in a mesh structure, and the remaining adhesive layers may be formed by applying a thermoplastic resin in the form of powder or pellets, or both adhesive layers may be formed in a mesh structure. In the case of forming the adhesive layers having different structures, the air permeability is secured and the frequency range of the absorbable noises is changed and the noises are dispersed due to the different structures, thereby providing more excellent sound absorption performance. Due to the adhesive layer of the irregular mesh structure, it is possible to additionally absorb noise in the non-absorbed frequency region while passing through the nonwoven fabric layer, and the adhesive layer itself is breathable so that the sound absorbing performance of the entire carpet is not impaired.

In this case, the amount of the thermoplastic resin applied in the form of a nonwoven fabric or film or a powder or pellet used for the thermal bonding function is preferably 50 to 300 g / m ² . When the amount of the thermoplastic resin used is less than 50 g / m 2, sufficient adhesive strength may not be exhibited. If the amount of the thermoplastic resin is more than 300 g / m 2, excessive weight of the vehicle parts may be a problem, and air permeability of the adhesive layer 12 may be deteriorated.

Car sound absorbing carpets made of a carpet layer and a non-woven fabric layer of a double structure is made of fibers with different fineness and have a different surface density and thickness, so that the sound absorption coefficient is different accordingly to maximize the sound absorption effect Can be. The thickness direction air permeability of the entire sound absorbing carpet of the present invention is in the range of 3 to 40 (cm 3 / cm 2 sec) and the sound absorption coefficient is 0.3 to 0.8.

Since the sound absorbing carpet for automobiles of the present invention has excellent sound absorbing performance as described above, it can be used as a car mat of a car or an auxiliary mat laid on the car mat, but is not particularly limited to such a use.

Hereinafter, the present invention will be described in more detail with reference to Examples, but embodiments according to the present invention can be modified in many different forms, and the scope of the present invention is construed as being limited to the embodiments described below. Can not be done.

<Example 1>

1300den / 68fila nylon BCF yarns are made of polyester spun nonwoven fabrics with a surface density of 130g / m ² , and the fabric is woven in the form of a flush pile so that the pile height is 9mm and the weight per unit area of pile fiber is 610g / m ² . After dyeing and processing, 80 g / m ² backcoating was performed with ethylene vinyl acetate (EVA) latex.

The first nonwoven fabric layer is single yarn fineness of 0.3 dtex in 65den / 190fila direct spinning a polyester made of a microfine fiber 100%, a spun lace 0.5mm thickness, area density 100g / m ^2, air permeability 21㎤ / ㎠sec and winding coefficient 0.35 Nonwoven fabric was used. The second nonwoven layer was made of 75den / 36fila polyester fiber having a single yarn fineness of 1.9 decitex, and used a needlepunch nonwoven fabric having a thickness of 2.5 mm, a surface density of 500 g / m ² , an air permeability of 37 cm 3 / cm ² sec and a damping coefficient of 0.25. . One side of the second nonwoven layer which is in contact with the mat was used by slightly burning the surface of the nonwoven fabric with a gas flame in order to prevent slipping, thereby providing a rough surface texture.

Adhesion between the first nonwoven fabric layer and the second nonwoven fabric layer is performed by spraying polyethylene powder at 60 g / m ² on top of the second nonwoven fabric layer and heating and melting it at 150 ° C. with hot air, and then passing the cold nonwoven layer material through a cold press roll. Was attached. The adhesion between the double-layered nonwoven fabric layer and the carpet thus adhered is 150 g / m ² of polyethylene powder dispersed on top of the first nonwoven fabric layer of the double-structured nonwoven fabric layer and heated and melted by heating at 150 ° C., followed by stacking the carpet layer. While passing through the cooling pressure roll was attached.

Example 2

Instead of spraying and applying polyethylene powder to the adhesion of the first nonwoven fabric layer and the second nonwoven fabric layer and the adhesion of the carpet and the double structure nonwoven fabric layer, the thickness of the polyethylene fiber material having a single yarn fineness of 1.9 decitex is 0.7 mm and the surface density is 120 g / It was prepared in the same manner as in Example 1 except that the spunbonded nonwoven fabric of m ² was placed between the materials to be attached, heated and melted by heating at 150 ° C., and passed through a cold pressing roll while overlapping the materials to be attached.

Example 3

Instead of spraying and applying polyethylene powder to the adhesion of the first nonwoven fabric layer and the second nonwoven fabric layer and the adhesion of the carpet and the double structure nonwoven fabric layer, the polyethylene resin is melted on one side of the attachment surface and laminated so that the coating amount is 250 g / m ^2. While manufacturing the same as in Example 1 except for attaching the other adhering material by passing through a cold pressing roll.

<Example 4>

Bonding between the double-layered nonwoven fabric layer and the carpet is made by placing an irregular mesh-shaped polyethylene nonwoven fabric on the top of the nonwoven fabric layer and heating it by heating it at 150 ° C. with hot air to melt it. Except that manufactured in the same manner as in Example 1.

<Example 5>

Adhesion of the first nonwoven fabric layer and the second nonwoven fabric layer was performed in the same manner as in Example 1 except that the nonwoven fabric was bonded using a polyethylene nonwoven fabric having an irregular mesh shape as in Example 4.

<Example 6>

It was prepared in the same manner as in Example 1 except that an irregular mesh-type polyethylene nonwoven fabric was used for bonding the first nonwoven fabric layer and the second nonwoven fabric layer, and for bonding the carpet and the double structure nonwoven fabric layer.

<Example 7>

The amount of powder or powder was used except that the polyethylene masterbatch containing 8 wt% of zeolite having an average particle size of 2.5 to 3.5 μm was used as a powder for adhesion between the first nonwoven fabric layer and the second nonwoven fabric layer, and the adhesion between the carpet and the double structure nonwoven fabric layer. The method of heat-melting and bonding with hot air and the like was prepared in the same manner as in Example 1.

Comparative Example 1

Aside from the removal of the first nonwoven fabric layer, which contributes to the improvement of sound absorption performance, and the direct attachment of the second nonwoven fabric layer to the carpet layer, the adhesive method and the rest were prepared in the same manner as in Example 1.

The air permeability and sound absorption rate of the vehicle carpet manufactured through the above Examples and Comparative Examples were evaluated based on the following evaluation method and are shown in Table 1.

<Evaluation of breathability>

The breathability evaluation of the nonwoven fabric material and the whole carpet was measured by the method of JISL1096-1999 (A method of 8.227.1) standard. The unit is expressed in cm 3 / cm 2 sec and means the amount of air (cm 3) permeating 1 cm 2 unit area per second.

<Evaluation of sound absorption rate>

When the negative energy incident on the surface of the sound absorbing material is Ei and the negative energy reflected on the surface is Er, the sound absorption coefficient (α) is defined as follows.

 α = 1- (Er / Ei)

The sound absorption coefficient was measured by the reverberation chamber method measured in the reverberation chamber according to the KS F 2805 standard, which is a condition near random incidence, and the performance of the sound absorption coefficient was evaluated by the sound absorption coefficient. Noise Reduction Coefficient (NRC) is a value that represents the characteristic of sound absorption coefficient value in 500 ~ 2000Hz, which is the frequency range of air transmission noise flowing into the vehicle interior. It is an arithmetic mean value, the better the value is.

TABLE 1

division First nonwoven fabric layer Second nonwoven layer Remarks Carpet full Breathability (cm 3 / cm 2 / sec) Attenuation coefficient Breathability (cm 3 / cm 2 / sec) Attenuation coefficient Breathability (cm 3 / cm 2 / sec) Attenuation coefficient Example 1 21 0.35 37 0.25 Polyethylene Powder Adhesion 18 0.62 Example 2 21 0.35 37 0.25 Bonding with Polyethylene Nonwovens 15 0.56 Example 3 21 0.35 37 0.25 Adhesion through Polyethylene Laminating 2 0.48 Example 4 21 0.35 37 0.25 Bonding using a mesh-type polyethylene nonwoven fabric 20 0.65 Example 5 21 0.35 41 0.27 Bonding using a mesh-type polyethylene nonwoven fabric 19 0.64 Example 6 21 0.35 41 0.27 Bonding using a mesh-type polyethylene nonwoven fabric 24 0.67 Example 7 21 0.35 37 0.25 Adhesion using polyethylene powder containing inorganic filler 19 0.65 Comparative Example 1 - - 37 0.25 First nonwoven fabric layered Polyethylene powder adhesive 35 0.51

In the case of Example 1, the sound absorption coefficient which is a numerical value which shows sound absorption performance showed the best performance. In the case of Example 2, the polyethylene nonwoven fabric is placed between the adhesive surfaces and melt bonded instead of the melt bonding method after spraying the polyethylene powder, so that the attaching surface is relatively more compact, so the breathability is lowered and the noise is difficult to pass. Therefore, the damping coefficient of the entire carpet is lower than that of the first embodiment.

In Example 3, since the adhesive surface is formed by the sound insulating lamination method instead of the air permeable adhesive method, the air permeability is almost eliminated, and the overall damping coefficient of the carpet is lower than that of the first and second embodiments. Example 4 is a case of using a non-woven polyethylene nonwoven fabric in the process of bonding the nonwoven fabric layer and the carpet of the double structure and Example 5 is a polyethylene nonwoven fabric of irregular mesh shape for the adhesion of the first nonwoven fabric layer and the second nonwoven fabric layer In the case of using the air permeability of the adhesive surface is better than Example 1 or Example 2, it was possible to obtain more improved results of the coefficient of damping of the entire carpet.

In the case of Example 6, in which a nonwoven mesh-like polyethylene nonwoven fabric is used for bonding the double-woven nonwoven fabric layer and the carpet and the first nonwoven fabric layer and the second nonwoven fabric layer, the sound absorption coefficient is excellent and the sound absorption is excellent. The result was obtained. In the case of Example 7 using the polyethylene powder mixed with inorganic fillers, the results of air permeability and coefficient of attenuation were slightly improved than those of Example 1 without using the inorganic fillers.

Comparative Example 1 uses the breathable adhesive method, but the first nonwoven fabric layer having the greatest contributing effect to the sound absorbing performance is eliminated, so the air permeability of the entire carpet is the best, but the first nonwoven fabric layer has no sound absorbing effect due to the ultrafine fibers. The damping coefficient was lower than that of Example 1.

Although the present invention has been described in detail only with respect to specific examples, it will be apparent to those skilled in the art that various changes and modifications can be made within the technical spirit of the present invention, and the present invention is directed to such modifications and variations. It is not limited.

According to the present invention, two nonwoven fabric layers having different damping coefficients are laminated, and a sound absorbing carpet for automobiles is manufactured by using an irregular mesh-shaped thermoplastic nonwoven fabric or a powder of a thermoplastic resin and an inorganic filler mixture as an adhesive layer. When used as a mat, it can effectively absorb the noise inside and outside the car.

1 is a cross-sectional view of a sound absorbing carpet 1 for a vehicle according to an embodiment of the present invention.

Claims (7)

In the sound absorbing carpet for automobiles, Tufted or needled yarns of one kind selected from the group consisting of polyester, nylon, polypropylene, cotton, hemp, and wool are bonded on a nonwoven fabric made of polypropylene or polyester, and the bottom surface is ethylene vinyl. Carpet layer 11 back-coated with at least one selected from the group consisting of acetate, styrene butadiene rubber, natural latex and polyethylene, A first nonwoven fabric layer 13 formed of at least one selected from the group consisting of polyesters, polypropylenes, and polyamides with a microfiber nonwoven fabric, and A second nonwoven layer 14 formed of a nonwoven fabric of at least one selected from the group consisting of polyester, polyolefin, polyethylene, and polystyrene, The damping coefficients of the first nonwoven fabric layer 13 and the second nonwoven fabric layer 14 are different from each other, and the first nonwoven fabric layer 13 has a fiber having a single yarn fineness of 0.05 to 20 decitex. Car sound absorption carpet, characterized in that the weight%. The sound absorbing carpet of claim 1, wherein the first nonwoven fabric layer has a thickness of 0.1 to 5.0 mm, a surface density of 50 to 500 g / m ² , and a damping coefficient of 0.3 to 0.8. delete 2. The sound absorbing carpet for automobiles according to claim 1, wherein the second nonwoven fabric layer has a thickness of 0.5 to 50 mm, a surface density of 100 to 1,000 g / m ² , and a damping coefficient of 0.2 to 0.8. The method of claim 1, wherein at least one of the adhesive layer 12 that bonds the carpet layer 11, the first nonwoven fabric layer 13 and the second nonwoven fabric layer 14 to heat-melt thermoplastic resin nonwoven fabric having an irregular network structure Car sound absorbing carpet, characterized in that formed. The method of claim 1, wherein at least one of the adhesive layer 12 adhering the carpet layer 11, the first nonwoven fabric layer 13, and the second nonwoven fabric layer 14 comprises a mixture of a thermoplastic resin and an inorganic filler in powder form. Sound-absorbing carpet for automobiles, characterized in that formed by pulverizing after heating. The sound absorbing carpet for automobiles according to claim 6, wherein the amount of the inorganic filler is 1 to 10% by weight of the thermoplastic resin in the mixture of the thermoplastic resin and the inorganic filler.

Images