JP2006016738A - Spunbonded nonwoven fabric suitable to ground fabric for sound-damping material and sound-damping material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spunbonded nonwoven fabric to ground fabric for sound-damping material, excellent in reinforcing function, form-retaining function and shock-absorbing function. <P>SOLUTION: The spunbonded nonwoven fabric with filaments interlaced with each other has a basis weight of 50-1,000 g/m<SP>2</SP>and a thickness of 0.5-10.0 mm. This spunbonded nonwoven fabric is composed of a dense layer and a bulky layer. More specifically, this spunbonded nonwoven fabric is 5-100% in the rate of falling ball maximum shock absorption. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a spunbonded nonwoven fabric that is optimal for a soundproofing material base fabric, and to a sound deadening material using the spunbond.

  It is generally known to use a nonwoven fabric for various base fabrics such as a sound absorbing material and a shock absorbing material. For example, Patent Document 1 proposes a pipe in which an inorganic fiber web or an inorganic powder is hardened with a soft synthetic resin and wound with a sheet imparted with a silencing function. However, this proposal has a problem that it lacks versatility because it takes measures to harden the outside with mortar.

  Further, Patent Document 2 proposes a method of absorbing sound by putting cotton or a soft foam material in the inner layer of a sound insulation sheet containing a high specific gravity metal, but this method lacks versatility because it uses a sound insulation sheet. The silencing effect is also insufficient.

  In order to improve this method, the inner layer is made of cotton, felt, mat, and a cylindrical fiber layer to hold the air to give the sound absorbing layer function, and the outer layer is provided with an elastic resin to provide the sound insulating layer and damping layer function. Patent Document 3 proposes a multilayer structure that fulfills the above. However, this method has a problem that the thickness is large and the sound absorbing function of the nonwoven fabric is insufficient compared with that of the soft foam, so that the sound absorbing effect is insufficient and the versatility is lacking.

  Further, Patent Document 4 proposes a method in which sound is passed through a non-woven fabric in contact with a sound source, and the sound is absorbed and blocked by an outer closed cell resin body. However, as the nonwoven fabric to be used, polypropylene long fibers are embossed, and the reinforcing function uses a resin reinforcing body separately, and the nonwoven fabric does not have a reinforcing effect.

  In addition, the fiber aggregate layer and the foamed resin layer are joined by needle punching, and the laminated material joined to the pile fabric etc. via the adhesive layer is attached to the wall surface or floor surface, etc., and sound insulation is applied to the wall surface or floor surface. Patent Document 5 proposes a method for providing functions such as noise reduction, heat insulation, and prevention of condensation. However, the nonwoven fabric used in this method is not particularly limited, and there is a description that hard cotton or a spread web can be used, and only the entanglement function of the heat insulation layer of the carpet is given.

Further, Patent Document 6 proposes a soundproof heat insulating sheet obtained by laminating a thick felt or mat made of a synthetic fiber and a film and tangling with a needle punch. The nonwoven fabric used in this case is disclosed as having a basis weight of 100 to 1500 g / m ² and a thickness of 1 to 15 mm. The reinforcing effect is retained by the film, and the nonwoven fabric is assumed to function as a heat insulating layer. .
JP 05-215289 A Japanese Patent Publication No. 06-089560 JP 2001-214996 A JP 09-089357 A JP 2001-214996 A Special table 2003-535228 gazette

Although the nonwoven fabric which has heat insulation and a sound absorption property is disclosed as mentioned above, the nonwoven fabric suitable for the silencer base fabric excellent in the reinforcement function, the shape maintenance function, and the impact absorption function is not disclosed.

The present invention has been made against the background of the problems of the prior art, and proposes a spunbonded nonwoven fabric suitable for a sound-absorbing material base fabric having excellent reinforcement function, shape retention function, and shock absorption function.

As a result of diligent research to solve the above problems, the inventors of the present invention formed a specific structure with only a nonwoven fabric, thereby improving the impact absorbing function, resulting in an improved reinforcing function and a form retaining function, The inventors have found that an excellent silencing function can be expressed, and have finally completed the present invention. That is, the present invention provides, in (A) a basis weight of ^{50g / m 2 ~1000g / m 2} , a thickness of the long fibers 0.5mm~10.0mm was entangled nonwoven fabric, the nonwoven fabric is from the dense layer and the bulky layer Constructed spunbond nonwoven. (B) the absorption rate of the maximum impact force by a falling ball is 5% ~100% (A) a spunbonded nonwoven fabric according, (C) apparent density ^{100kg / m 3 ~250kg / m 3} , and the dense layer The bulky layer is integrated, the dense layer surface has an uneven shape, and the spunbonded nonwoven fabric according to (A) or (B), wherein the recessed area is 8% to 70%, and (D) the dense layer is embossed or The spunbonded nonwoven fabric according to (A) to (C), wherein the bulky layer is formed by a needle punching process or a hydroentanglement process, and (E) (A) to (D). ) A silencing material using the nonwoven fabric described in any one of the above, (F) Embossing roller temperature on the side forming a dense layer when embossing a spunbond nonwoven fabric that has been subjected to needle punching and hydroentanglement ( Te: ° C) is non-woven When the melting point (Tm: ° C.) of the resin constituting the fiber is satisfied, the formula (Tm-8) ≧ Te ≧ (Tm-80) is satisfied, and the embossing roller temperature on the bulky layer side is set to 5 ° C. to 100 ° C. It is a manufacturing method of the spunbonded nonwoven fabric characterized by processing.

The spunbond nonwoven fabric of the present invention is inexpensive as a spunbond nonwoven fabric suitable for a sound-absorbing material base fabric that has excellent reinforcement function, shape retention function, and shock absorption function by forming a specific structure that satisfies the requirements of the present invention even with the nonwoven fabric alone. Can be provided.

Hereinafter, the present invention will be described in detail.
The present invention, a basis weight of ^{50g / m 2 ~1000g / m 2} , in a thickness of the long fibers 0.5mm~10.0mm was entangled nonwoven fabric, the nonwoven fabric is composed of a dense layer and the bulky layer span Bond nonwoven fabric.

  When the fibers constituting the nonwoven fabric are not continuous fibers, the impact absorption and silencing functions are halved, and a sheet composed of the nonwoven fabric alone cannot provide a sufficient silencing function. Nonwoven fabrics not composed of fibers are not preferred. Moreover, even if it is composed of continuous fibers, a non-woven fabric that cannot exhibit a rigid function upon impact, such as a melt blown non-woven fabric, is not preferable.

Basis weight of the nonwoven fabric according to the present invention is ^{50g / m 2 ~1000g / m 2} . If it is less than 50 g / m ² , when the apparent density is set within the range of the present invention, there may be a case where only a structure having insufficient shock absorption and silencing functions can be achieved. If it exceeds 1000 g / m ² , there is a problem that the sound-absorbing sheet becomes too heavy, which is not preferable. Preferred mass per unit area of the present invention is a ^{100g / m 2 ~500g / m 2} , more preferably from ^{150g / m 2 ~300g / m 2} .

If the thickness of the nonwoven fabric of the present invention is less than 0.5 mm, the effect of receiving and dispersing the impact on the surface and silencing with the lower shock absorber may be insufficient, which is not preferable. When the thickness exceeds 10.0 mm, other materials can be substituted, and the goodness of the nonwoven fabric of the present invention may not be utilized, which is not preferable. The preferable thickness of this invention is 0.6 mm-5.0 mm, More preferably, it is 0.8 mm-2.5 mm.

The structure of the nonwoven fabric of the present invention is a dense layer that receives a shock as a rigid body, disperses the shock and transmits it to the lower layer, and a shock that eliminates the shock by the effect of confining the transmitted shock wave as a structural deformation and wave in the air gap At least a two-layer structure of a bulky layer having an absorber function is required. When the two-layer structure is not formed, the above effect cannot be exhibited, which is not preferable.

The nonwoven fabric of the present invention is preferably a spunbonded nonwoven fabric having a two-layer structure and a maximum impact force absorption rate of 5 to 100% due to falling balls. If the absorption rate of the maximum impact force by the falling ball is less than 5%, the sound deadening function may be insufficient. The more preferable range of the absorption rate of the maximum impact force by the falling ball of the present invention is 8% or more, most preferably 10% or more and 100%. In order to mute more efficiently, it is desirable to set the optimum thickness of each layer according to the basis weight, density, and thickness. A preferable dense layer / bulky layer thickness ratio is 0.5 / 0.5 to 0.03 / 0.97. When the dense layer ratio exceeds 0.5, the bulky layer becomes thin, the shock absorber effect of the bulky layer may be reduced, and the shock absorption and silencing function may be reduced. When the dense layer ratio is less than 0.03, This is because there is a case where the function of receiving and receiving an impact on the surface of the rigid body is lowered. A more preferable dense layer / bulky layer thickness ratio is 0.4 / 0.6 to 0.05 / 0.95.

Apparent density of the present invention the nonwoven fabric is defined by the apparent density of the combined average of the dense layer and the bulky layer, apparent density preferably ^{100kg / m 3 ~300kg / m 3} . If the apparent density is less than 100 kg / m ³ , the apparent density of the dense layer becomes low, and the surface rigidity for receiving impact on the surface may be insufficient, which is not preferable. If it is 300 kg / m ³ or more, the density of the bulky layer becomes high, and the shock absorber function of the dense layer may be insufficient, which is not preferable. More preferably the apparent density of the present invention is ^{150kg / m 3 ~290kg / m 3} , most preferably ^{180kg / m 3 ~280kg / m 3} . Incidentally, the preferable apparent density of the dense layer is 200 kg / m ³ or more, more preferably 300 kg / m ³ or more and 1000 kg / m ³ or less. Preferred Apparent density of bulky layer ^{80kg / m 3 ~300kg / m 3} , more preferably from ^{100kg / m 3 ~250kg / m 3} .

The two-layer structure of the nonwoven fabric of the present invention is a preferred embodiment because when the dense layer and the bulky layer are joined and integrated, the efficiency of shock absorption and sound deadening function is improved. In order to simplify the laminating and bonding process, it is most preferable to form a two-layer structure of an integral structure, but a method of bonding two separate layers may be used. In the case of bonding, a known method such as needle punching or adhesion is used. As a preferable example, it is preferable that they are joined and integrated.

In addition, the dense layer that receives the impact imparts a surface shape having a concavo-convex shape in addition to the rigid body function, so that the impact is applied by deforming the convex portion before the impact is transmitted to the rigid body layer on the bottom of the dense layer. Since the structure having both the impact absorbing ability to relieve the vibration and the efficiency of the impact absorbing and silencing functions are very good, it can be exemplified as the most preferable example. The crushing area of the recess that exhibits the rigid function is preferably 8% to 70%. If it is less than 8%, the rigid body function becomes insufficient, and the impact force may not be distributed and transmitted to the soft layer. When it exceeds 70%, the convex portion is reduced, and the impact relaxation efficiency may be insufficient. A more preferable recess area is 16% to 60%, and most preferably 20% to 50%.

If the bottom surface has irregularities, the stress concentrates on the convex portions below and the transmission to the soft layer becomes non-uniform, which is not preferable. For the surface roughness, for example, single-sided embossing that can form unevenness only on the dense layer surface, or roasting can be recommended. In addition, the bulky layer is preferably formed by needle punching or hydroentanglement. As described above, the method of forming a dense layer directly on the soft layer by embossing or roasting is especially recommended for forming the two-layer structure, but the soft layer that integrates the non-woven fabrics created separately is made into two layers. You can also

If the composition of the fiber which comprises the nonwoven fabric of this invention is a composition which can form a spun bond nonwoven fabric, it will not specifically limit. For example, thermoplastic resins such as polyester, polyamide, polyolefin, polyurethane, polyvinyl alcohol, and polycarbonate can be exemplified, but preferred compositions of the present invention include aromatic polyesters excellent in heat resistance and durability. The aromatic polyester contains, as a main component, a polyester unit of an aromatic dicarboxylic acid and a diol such as ethylene terephthalate, ethylene naphthalate, trimethylene terephthalate, trimethylene naphthalate, butylene terephthalate, butylene naphthalate, and cyclohexylene dimethyl terephthalate. Examples thereof include polyester. If necessary, as the other third component, the acid component is a copolymer of a third component such as isophthalic acid, adipic acid, sebacic acid, glutaric acid or the diol component is diethylene glycol, neopentyl. Examples thereof include polyesters obtained by copolymerizing diol components such as glycol and butanediol / ethylene glycol. Alternatively, copolymerization may be performed when the copolymerized aromatic polyester or aliphatic polyester is mixed and melted.

In the present invention, various functions can be achieved by adding other resin components, deodorizing antibacterial agents, deodorants, antifungal agents, coloring agents, fragrances, flame retardants, plasticizers, compatibilizers, etc., as long as the performance is not deteriorated. Grant can be made.

Although the fiber which comprises the nonwoven fabric of this invention is not specifically limited, 0.5 dtex-6 dtex which can express intensity | strength and rigidity in a dense layer are preferable, and 2 dtex-10 dtex which can show bulkiness in a bulky layer are preferable. The cross-sectional shape is preferably a round cross section or a flat cross section for the dense layer, and a hollow cross section or a specially modified cross section for the bulky layer.

The fiber arrangement of the nonwoven fabric structure of the present invention is not particularly limited. However, in the tape application, it is preferable to use an orthogonal arrangement or a fiber arrangement that is arranged in series in the extension direction because the strength during extension can be increased. For sheet use, an orthogonal arrangement or a random arrangement is preferred in which the strength can be increased when stretched in all directions.

The strength, elongation and tear strength of the nonwoven fabric of the present invention are not particularly limited, but the preferred range from handling and durability to use is that the strength is 50 N / 50 mm to 400 N / 50 mm, the elongation is 40% to 100%, The tear strength is 20 N / 50 mm to 200 N / 50 mm.

Below, an example of the manufacturing method of this invention nonwoven fabric is shown.
The two-layer structure of the dense layer and the bulky layer of the nonwoven fabric of the present invention can also be obtained by a method in which the dense layer and the bulky layer are separately prepared and laminated and integrated. In addition, one side of a single-layer nonwoven fabric made of a soft layer can be made into a dense structure. The two-layer structure of the single-layer nonwoven fabric uses a technique in which only one surface is heated and the lower layer is cooled to make the bulky layer stiff while the bulky layer is stiffened while the bulky layer is stiffened to leave the bulky layer. It is particularly preferred.

Further, the nonwoven fabric according to the present invention can be made into a two-sided dense structure by joining soft layers separately made into a nonwoven fabric into two layers.
When such a method is employed, the dense layer is preferably 200 kg / m ³ or more, and the bulky layer is preferably less than 200 kg / m ³ .

The production method of the present invention is illustrated below.
Spinning is carried out by a conventional method using polyethylene terephthalate (hereinafter abbreviated as PET) having an intrinsic viscosity of 0.68. On the side to be the dense layer, it is preferable to spout a flat section discharge yarn from the discharge hole of the slit. In order to set the preferred fineness of the present invention to 0.5 dtex to 6 dtex, when the take-up speed by the ejector is set to 5000 m / min, for example, the discharge amount is set to 0.25 g / min hole to 3 g / hole. Is preferred. At this time, unless the shear rate is set to 10000 / second or less, the fiber strength may be reduced due to abnormal flow. A preferable shear rate is 300 / sec to 4000 / sec, and it is particularly preferable that the orifice is set in a range of 500 to 3000 / sec, particularly when the orifice has a slit shape or an irregular cross-sectional shape.

As the nozzles to be ejected, a required number of small nozzles in multiple rows may be installed, or a single nozzle having multiple rows of holes may be used. The discharged molten filament is thinned while being cooled and taken off. In the spunbonding method, a web is formed by picking up with an ejector having an aspirator function, and shaking on a transport net to open and laminate the fiber arrangement in a random state. If the fiber is delayed and recovered within the elastic recovery limit and the nonwoven fabric's shape retention is reduced and handling becomes worse, a method of fixing the web form by immediately suppressing delayed recovery of the spread and laminated web is recommended. it can.

Examples of the fixing method include a method of pinching and fixing with a take-off net and a method of fixing with a pressing roller. Thereby, the form retainability of a nonwoven fabric improves remarkably. The amount of fibers to be shaken off is adjusted according to the take-up net speed so as to obtain a desired basis weight. In the case where the number of spun fibers is constant, when the take-up net speed is increased, the opened fibers tend to be more likely to be arranged in the net traveling direction (hereinafter abbreviated as MD). In such a case, it is possible to adjust the random state by increasing the number of fibers to be shaken off, and the productivity is further improved. In the process of forming the take-up web, it is necessary to consider necessary thickness adjustment.

As the fiber cross section on the bulky layer side, a round cross section, a modified cross section, a hollow cross section or the like can be exemplified as a preferable orifice shape. In order to set the fineness of 2 dtex to 10 dtex, which is a preferable fineness of the present invention, when the take-up speed by the ejector is set to, for example, 5000 m / min, the discharge rate is preferably 1 g / min to 5 g / min. For other conditions, a laminated web can be obtained by the same method as that for forming the dense layer.

Next, the laminated web is continuously or discontinuously subjected to entanglement treatment such as needle punching or hydroentanglement treatment to form a bulky layer. In the case of multiple layers, webs are stacked and entangled. In needle punching, it is preferable to optimize the needle number density and the needle shape according to the density and the entanglement strength. The hydroentanglement process is performed on one side or both sides as necessary. A water flow pressure of 300N to 800N is appropriate. If the pressure is too low, the entanglement effect is small. If the pressure is too high, fiber damage occurs, which is not preferable. The bulky layer thus obtained then forms a dense layer on the side surface to be a dense layer.

In the dense layer formation, a densification process is performed on the side surface of the laminated bulky layer as a dense layer continuously or discontinuously. For the densification process, embossing or hair burning can be recommended. In a preferred embodiment of the present invention, the embossing is a shape such as a crease pattern, a lattice pattern, a turtle shell pattern, a horizontal ellipse pattern, etc., which are embossed shapes that can be processed to be uneven, and the crushing rate is preferably 8% to 70%. . More preferably, it is 16% to 60%. The linear pressure is preferably 200 N / cm to 900 N / cm for PET fibers, and the roller temperature is desirably heated on the embossed side and cooled on the anti-embossed side. That is, when embossing a spunbond nonwoven fabric that has been subjected to needle punching or hydroentanglement, the embossing roller temperature (Te: ° C) on the side that forms the dense layer is the melting point of the resin that constitutes the fibers of the nonwoven fabric ( Tm: ° C.) satisfying the formula (Tm−8) ≧ Te ≧ (Tm−80), and embossing is performed with the embossing roller temperature on the bulky layer side being 5 ° C. to 100 ° C. Nonwoven manufacturing methods are particularly recommended.

When the embossing roller temperature is a high temperature less than the resin melting point −8 ° C., it is desirable to avoid the case where the fiber form cannot be maintained due to the molten or semi-molten state. A melting point of −80 ° C. or lower is not preferable because the effect of plastic deformation of the fiber is insufficient and the formation of a rigid face may be insufficient. The embossing roller temperature (Te) is preferably Tm-10 ° C to Tm-50 ° C, more preferably Tm-15 ° C to Tm-40 ° C. The anti-embossing roller is preferably 5 to 100 ° C. because it needs to be cooled to prevent thermal deformation of the bulky layer and maintain bulkiness. If it is 5 ° C. or less, it is a technically desirable condition, but the energy efficiency for cooling deteriorates, which is disadvantageous in terms of cost. Above 100 ° C., the bulky layer may be thermally deformed, which is not preferable.

The spunbonded nonwoven fabric for sound deadening material of the present invention thus obtained can be provided as a sound absorbing material base fabric. Next, the base fabric is joined to the adhesive laminated with the release film to obtain a sound deadening sheet. In order to obtain a tape, it is supplied as a cut and wound tape in a desired width.

In the present invention, a function imparting agent such as deodorant antibacterial, deodorant, antibacterial, coloring, aroma, flame retardant, etc. is applied at any stage of processing from a resin production process to a molded product within a range that does not deteriorate the performance and commercialization. Can be processed. In addition, the illustration in this invention is not limited to these.

Next, the present invention will be specifically described with reference to examples and comparative examples. The characteristic values in the examples and comparative examples were measured by the following methods.

<Melting point>
An endothermic peak temperature of an endothermic phenomenon caused by melting when the temperature is increased from 20 ° C. to 300 ° C. at 20 ° C./min with a differential scanning calorimeter is defined as a melting point.
<Fine fineness>
Measured according to JIS-L1015 (1999).
<Weight of nonwoven fabric>
Measured according to JIS-L1906 (2000).
<Thickness of nonwoven fabric>
Measured according to JIS-L1906 (2000).
<Tensile strength, elongation, and stress at 5% elongation of nonwoven fabric>
Measured according to JIS-L1906 (2000). The stress at 5% elongation is the stress at 5% elongation when measuring the tensile strength and elongation.
<Dry heat shrinkage of nonwoven fabric>
Measured according to JIS-L1906 (2000).
<Recessed area ratio>
In 10 photos of nonwoven fabric 1m2 randomly selected 10 mm (1 cm2) in width and photographed the uneven surface, the recess was individually cut out, and the area ratio to the total area was obtained. The average of 10 locations is shown as%.
<Absorption rate of maximum impact force by falling ball>
The maximum impact load (σmax) when dropped into the center φ10mm of the load receiving surface φ100mm of the compression load cell installed below 500mm using 5/8 parallel balls of ball balls for ball bearing specified in JIS B 1501. Then, the sample is placed in the center of the load receiving surface φ100 mm, and the steel ball is dropped into the center φ10 mm of the load receiving surface φ100 mm from above the sample surface to measure the maximum impact load (σi). The reduction rate of the impact load is obtained as the absorption rate (Δσ) of the maximum impact force by the falling ball by the following formula. (N = 10)
Δσ (%) = 1 / nΣ (1-σi / σmax) × 100
<Form retention function>
As the shape retention, it is determined that the shape retention function is acceptable when the 5% elongation stress is 40 N / 5 cm or more as the resistance measure of extension deformation and the heat shrinkage rate is 2% or less as the heat deformation resistance measure.
<Reinforcing function>
A glass plate obtained by cutting a 2 mm thick plate glass into a width of 50 mm and a length of 200 mm is cut at a 100 mm point in the width direction by making a straight 50 mm wide cut, with the cut at the bottom, and the center of the cut at 150 mm intervals. If the plate glass is dropped at the center of the cut position of the sample mounting surface from the top of 100mm and the plate glass is broken, the reinforcing function is poor. (X) When it did not crack, it was determined that the reinforcing function passed (O). In addition, when not mounting | wearing with a sample, it confirms that all of n = 10 cracked. When all of n = 10 were not broken, the falling position was raised and the position that could be reliably broken was corrected to the falling ball position for evaluation. When the sample was mounted, if n = 10 and 7 or more were not cracked, it was regarded as slightly defective (Δ).
<Mute effect>
Install a 500mm square steel plate (thickness 5mm) on a 480mm square point that can be supported by a rubber surface of φ10mm, and set the sound when a 5/8 parallel ball is dropped from 150mm above the steel plate surface as first grade. Compared to the case where a sample was attached by 10 panelists, with a sound of 5 grades when a steel ball was dropped from 150 mm above the natural rubber plate surface with a 5 mm soft natural rubber plate attached to the steel plate surface, In the sensory evaluation, grades 1 to 5 were determined, and an average value (rounded down to the nearest decimal point) was calculated, and grades 3 and higher were judged to have a silencing effect.

Example 1
PET having an intrinsic viscosity of 0.68 and a melting point of 265 ° C. was spun from an orifice having a width of 0.05 mm and a length of 0.2 mm at a spinning temperature of 285 ° C. at a single hole discharge rate of 0.5 g / min, and 50 mm below the nozzle. While cooling the air at 20 ° C at a wind speed of 0.5 m / sec, the air is sucked at a yarn speed of 4900 m / min with an ejector installed at a point of 0.8 m below the nozzle, and then 1.5 m below the nozzle. Then, the fiber bundle was spun off and laminated on the surface of the take-up net moving at a speed of 50 m / min. The web laminated on the net surface is immediately pre-compressed with a temporary pressing roller and the fiber cross section is flattened with a take-off roller (flatness% = 1 / nΣ (short side / long side) × 100 to n = 20) 35% The dense layer web A having a fine cross section of 1 dtex and a basis weight of 60 g / m 2 was wound up.

A round cross section obtained in the same manner as the non-woven fabric A except that a round cross section with an orifice shape of φ0.3 mm was used for spinning at a single hole discharge rate of 3 g / min and the take-up net speed was 40 m / min. The fineness was 6 dtex. A laminated web B for a bulky layer having a basis weight of 100 g / m 2 was obtained.
Next, a dense layer web A and a bulky layer web B were stacked and supplied, and needle punched with a penet 60 to obtain a needle-punched spunbonded nonwoven fabric C.
Next, the needle-punched spunbonded nonwoven fabric C is a non-woven fabric side roller for a dense layer, a lattice pattern embossing roller with a crushing rate of 50% at a pitch of 0.8 mm, a temperature of 240 ° C., and a bulky layer side roller on a plain surface. While the bulky layer side was cooled at a temperature of 20 ° C., a spunbond nonwoven fabric D was obtained in which the dense layer side surface was embossed at a linear pressure of 500 Nf.

The thickness of the dense layer of the obtained spunbonded nonwoven fabric D is 0.08 mm, with irregularities, the concave area ratio is 44%, the thickness of the bulky layer is 0.71 mm, and the basis weight of the nonwoven fabric is 160 g / m2, Apparent density 202kg / m3, thickness 0.79mm, absorption rate of maximum impact force due to falling ball 10%, 5% elongation stress is 210N / 5cm in longitudinal (MD) direction, 145N / 5cm in transverse (CD) direction, dry heat The shrinkage ratio was 1.2% in the MD direction and 0.1% in the CD direction.
The obtained spunbonded nonwoven fabric D was laminated and joined to the adhesive layer side of the adhesive film laminated to the release film to create a sound deadening material, and the function evaluation was evaluated as a sound deadening sheet material. The shape retention function passed, the reinforcement function passed, and the silencing effect was grade 4 pass. That is, Example 1 satisfied all the requirements of the invention, and showed excellent performance as a silencer only by joining the nonwoven fabric of the present invention.

(Example 2)
PET having an intrinsic viscosity of 0.78 and a melting point of 266 ° C. was spun at a spinning temperature of 285 ° C., with a circular cross section having an orifice shape of φ0.25 mm, and a single hole discharge rate of 2 g / min. While cooling the air at a wind speed of 0.5 m / sec, the air is sucked by an ejector installed at a point of 0.8 m below the nozzle at a yarn speed of 5400 m / min. The fiber bundle was spun off and laminated on the take-up net surface moving at a speed of minutes. The web laminated on the net surface is immediately pre-compressed with a temporary pressing roller and taken up, continuously needle-punched with penet 50, the fiber cross section is a round cross section, the fineness is 3.7 dtex, and the nonwoven fabric thickness is 1.4 mm. A spunbonded nonwoven fabric E having a needle punching process with a basis weight of 80 g / m 2 was obtained. Next, while the spunbond nonwoven fabric E was cooled to 10 ° C. on one side of the nonwoven fabric, the heated embossing roller on one side was a lattice pattern embossing roller with a crush rate of 30% at a pitch of 0.8 mm, an embossing temperature of 235 ° C., A spunbonded nonwoven fabric F in which only the other one-sided surface layer was embossed at a linear pressure of 500 N / cm was obtained.

The obtained spunbonded nonwoven fabric F has a dense layer thickness of 0.08 mm, irregularities, a recess area ratio of 24%, a bulky layer thickness of 0.42 mm, and a nonwoven fabric weight per unit area of 80 g / m2. Load density 160kg / m3, thickness 0.5mm, absorption rate of maximum impact force due to falling ball 12%, 5% stress at elongation is 160N / 5cm in MD direction, 85N / 5cm in CD direction, dry heat shrinkage rate is 0 in MD direction 0.6% and CD direction 1.8%.
The obtained spunbonded nonwoven fabric F was laminated and bonded to the adhesive layer side of the release film laminated with the adhesive layer to create a silencing material, and the function evaluation was evaluated as a silencing sheet material. The shape retention function passed, the reinforcement function passed, and the silencing effect was grade 3 pass. That is, Example 2 satisfied all the requirements of the invention, and showed excellent performance as a sound deadening material by simply joining the nonwoven fabric of the present invention having a slightly thin thickness.

Example 3
The number of nozzle holes was increased, the take-up net speed was changed, and the laminated web was obtained by the same method as in Example 2 except that needle punching was performed with a penet 45. The fiber cross section was a round cross section and the fineness was 3.6 dtex, A spunbonded nonwoven fabric G subjected to needle punching with a thickness of 6.2 mm and a basis weight of 450 g / m2 was obtained. Next, the spunbond nonwoven fabric H obtained in the same manner as in Example 2 except that the emboss was used at a 1.2 mm pitch and a lattice pattern with a crushing rate of 72% was used, and the emboss temperature was 258 ° C. and the linear pressure was 800 N / cm. The thickness is 0.15 mm, the surface area is 61%, the bulky layer thickness is 2.5 mm, the basis weight of the nonwoven fabric is 450 g / m2, the apparent density is 170 kg / m3, the thickness is 2.65 mm, Absorption rate of maximum impact force due to falling ball 15%, 5% elongation stress is 1260N / 5cm in MD direction, 925N / 5cm in CD direction, dry heat shrinkage rate is 0.7% in MD direction and 1.9% in CD direction there were.

The obtained spunbonded nonwoven fabric H was laminated and bonded to the adhesive layer side of the adhesive film laminated to the release film to create a silencing material, and the function evaluation was evaluated as a silencing sheet material. The shape retention function passed, the reinforcement function passed, and the silencing effect was grade 4 pass. That is, Example 3 satisfied all the requirements of the invention, and showed excellent performance as a silencer simply by joining the nonwoven fabric of the present invention having a slightly thicker thickness.

Example 4
A dense layer spunbond nonwoven fabric L obtained by embossing only the web A obtained in Example 1 in the same manner as in Example 1 has a thickness of 0.09 mm, an apparent density of 670 kg / m ³ , and unevenness. The recess area ratio was 44%.

The web B obtained in Example 1 and the spunbonded nonwoven fabric L were laminated and needle punched with a penet 60 to obtain a laminated spunbonded nonwoven fabric M. The resulting nonwoven fabric has a basis weight of 160 g / m ² , an apparent density of 160 kg / m ³ , a thickness of 1.00 mm, a maximum impact force absorption rate of 15% due to falling balls, and a 5% elongation stress of 195 N / 5 cm in the machine direction (MD). The transverse (CD) direction was 153 N / 5 cm, and the dry heat shrinkage ratio was 1.1% in the MD direction and 0.2% in the CD direction.
The obtained spunbonded nonwoven fabric D was laminated and joined to the adhesive layer side of the adhesive film laminated to the release film to create a sound deadening material, and the function evaluation was evaluated as a sound deadening sheet material. The shape retention function passed, the reinforcement function passed, and the silencing effect was grade 4 pass. In other words, Example 4 satisfied all the requirements of the invention, and exhibited excellent performance as a sound deadening material only by joining the nonwoven fabric of the present invention.

(Comparative Example 1)
The spunbond nonwoven fabric I obtained by needle punching the laminated web B of Example 1 with a penet 60 has no dense layer, no irregularities on the surface, is a single layer of only a bulky layer, and the basis weight of the nonwoven fabric is 100 g / m2, Apparent density 84kg / m ³ , thickness 1.2mm, absorption rate of maximum impact force by falling ball 4%, 5% stress at elongation is 18N / 5cm in MD, 11N / 5cm in CD, dry heat shrinkage is MD The direction was 4.7% and the CD direction was 3.5%.
The obtained spunbonded nonwoven fabric I was laminated and joined to the adhesive layer side of the adhesive film laminated to the release film to create a silencing material, and the function evaluation was evaluated as a silencing sheet material. The shape retention function was rejected, the reinforcement function was rejected, and the noise reduction effect was also rejected at the second grade. That is, Comparative Example 1 did not satisfy all of the requirements of the invention, and although it had a thickness, it was inferior in performance as a silencer because it was a single layer.

(Comparative Example 2)
The spunbond nonwoven fabric J obtained in the same manner as in Example 2 except that the number of nozzle holes and the take-off speed were changed and a lattice-pattern embossed roller with a crushing rate of 50% at a pitch of 0.8 mm was used. The fineness is 3.7 dtex, the dense layer has a thickness of 0.05 mm, has irregularities, the recess area ratio is 46%, the bulky layer has a thickness of 0.25 mm, the basis weight of the nonwoven fabric is 45 g / m2, and the apparent density is 110 kg. / M3, thickness 0.3mm, absorption rate 3% of maximum impact force due to falling balls, 5% stress at the time of extension: MD direction 64N / 5cm, CD direction 41N / 5cm, dry heat shrinkage rate: MD direction 0.2% The CD direction was 0.1%.
The obtained spunbonded nonwoven fabric J was laminated and joined to the adhesive layer side of the adhesive film laminated to the release film to create a silencing material, and the function evaluation was evaluated as a silencing sheet material. The shape retention function was acceptable, the reinforcement function was unacceptable, and the noise reduction effect was also unacceptable at the second grade. That is, Comparative Example 2 did not satisfy all the requirements of the invention, and the performance was inferior as a silencer because the thickness was slightly thin.

(Comparative Example 3)
The spunbonded nonwoven fabric K obtained in the same manner as in Comparative Example 2 except that the number of nozzle holes and the take-up speed were changed, the embossing roller temperature was 262 ° C., and the linear pressure was 400 N / cm. Is 3.7 dtex, the dense layer thickness is 0.02 mm, has irregularities, the recess area ratio is 47%, the bulky layer thickness is 0.78 mm, the basis weight of the nonwoven fabric is 140 g / m2, and the apparent density is 175 kg / m3, thickness 0.8 mm, absorption rate of maximum impact force by falling ball 3.5%, stress at 5% elongation is MD direction 194 N / 5 cm, CD direction 180 N / 5 cm, dry heat shrinkage rate is 0.2 MD direction %, CD direction was 0.1%.
The obtained spunbonded nonwoven fabric J was laminated and joined to the adhesive layer side of the adhesive film laminated to the release film to create a silencing material, and the function evaluation was evaluated as a silencing sheet material. The shape retention function was acceptable, the reinforcement function was unacceptable, and the noise reduction effect was also unacceptable at the second grade. That is, Comparative Example 3 did not satisfy all of the requirements for the invention, and showed inferior performance as a sound deadening material.

(Comparative Example 4)
A 6.7 dtex staple cotton with a hollow cross section made of PET and a thermal adhesive component as a thermal adhesive component, a polyester copolymer having a melting point of 110 ° C. as a sheath component, and a 3.4 dtex thermal adhesive fiber with PET as a core component, 65% / 35 100% blended and opened with hot air at 140 ° C, 100g / m2, weight 1mm, apparent density 100kg / m3, maximum impact force absorptivity 3%, falling stress 5% Obtained a hard cotton having a MD direction of 11 N / 5 cm and a CD direction of 10 N / 5 cm (the dry heat shrinkage cannot be measured because the heat-adhesive component melts). The obtained spunbonded nonwoven fabric J was laminated and joined to the adhesive layer side of the adhesive film laminated to the release film to create a silencing material, and the function evaluation was evaluated as a silencing sheet material. The shape retention function was rejected, the reinforcement function was rejected, and the noise reduction effect was also rejected at the second grade. That is, the comparative example 4 was not comprised from the continuous fiber of invention requirements, and showed the performance inferior as a silencer.

As is clear from Examples 1 to 4 and Comparative Examples 1 to 4, the spunbonded nonwoven fabric of the present invention forms a specific structure that satisfies the requirements of the present invention alone with the nonwoven fabric alone, thereby providing a reinforcing function, a shape maintaining function, and an impact. It is possible to provide a spunbond nonwoven fabric that is optimal for a sound-absorbing material base fabric that has an excellent absorption function.

The spunbonded nonwoven fabric of the present invention can be provided at a low cost as a spunbonded nonwoven fabric that is optimal for a sound-absorbing material base fabric that has excellent reinforcement function, shape retention function, and shock absorption function. Furthermore, by making the basis weight and thickness desired, it can be provided as a non-woven fabric that is also useful for applications other than the sound-absorbing material base fabric, for example, filter applications that require a dense layer, which can contribute to the industry. It ’s big.

Claims (6)

Basis weight of ^{50g / m 2 ~1000g / m 2} , in the multilayer nonwoven fabric long fibers are entangled in thickness 0.5Mm～10.0Mm, the nonwoven fabric is configured spunbonded nonwoven fabric and a dense layer and the bulky layer.   The spunbonded nonwoven fabric according to claim 1, wherein the absorption rate of the maximum impact force by falling balls is 5% to 100%. Apparent density a ^{100kg / m 3 ~250kg / m 3} , the dense layer and the bulky layer are integrated into a dense layer surface has an irregular shape, according to claim 1 or concave area is 8% to 70% 2. The spunbond nonwoven fabric according to 2.   The spunbonded nonwoven fabric according to any one of claims 1 to 3, wherein the dense layer is formed by embossing or roasting, and the bulky layer is formed by needle punching or hydroentanglement.   A sound deadening material using the nonwoven fabric according to claim 1.   When embossing a spunbond nonwoven fabric that has been subjected to needle punching or hydroentanglement, the embossing roller temperature (Te: ° C) on the side forming the dense layer is the melting point of the resin constituting the nonwoven fabric fiber (Tm: )), And satisfies the formula (Tm-8) ≧ Te ≧ (Tm-80), and is embossed at an embossing roller temperature of 5 to 100 ° C. on the bulky layer side. Manufacturing method.