JP2006011276A - Fiber laminated sound absorbing material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound absorbing material which has small deterioration in weatherability with time and can be prevented from decreasing in sound absorptivity owing to entry of a raindrop and is excellently usable outdoors. <P>SOLUTION: The fiber laminated sound absorbing material is formed by laminating a surface material made of silk to which resin containing metal impalpable powder are imparted on a core material layer made of non-woven fabric of 0.01 to 0.1 g/cm<SP>3</SP>in apparent density. The metal impalpable powder are preferably impalable powder of aluminum. The silk is preferably fabrics. Further, the non-woven fabric forming the core material layer consists of subject fiber and binder fiber and is formed by uniting the constituent fiber with the binder fiber through thermal adhesion, and the subject fiber and binder fiber are made preferably of polyester copolymers. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sound absorbing material. In particular, it can be used as a sound-absorbing material for a soundproof wall used in civil engineering structures such as roads, railways, bridges, etc., airports, various stadiums, play facilities, etc. where noise countermeasures are required.

  The fiber aggregate has sound absorbing properties because there are voids between the fibers, and has been conventionally used as a sound absorbing material for various applications. Among them, the nonwoven fabric has a good sound absorption effect because the constituent fibers are randomly arranged and can maintain a sufficient thickness. For example, Patent Document 1 discloses a polyester polymer and a polyamide polymer. It has been proposed to use a nonwoven fabric using fibers made of a fiber-forming polymer such as a polyolefin polymer as a sound absorbing material.

  However, in applications that require noise countermeasures outdoors such as roads, railways, bridges, and other civil engineering structures, airports, various stadiums, and amusement facilities, the sound absorbing material is exposed to direct sunlight. If it is used as it is, there is a problem that the fiber is easily deteriorated by weathering. In addition, there is a problem that moisture enters the gaps of the sound absorbing material due to rain or the like and lowers the sound absorption rate.

In order to solve the above problems, an aluminum plate with a small hole is attached to the surface of the sound absorbing material to prevent it from being exposed to direct sunlight and to prevent the ingress of rainwater. It has been proposed to apply a fluorine-based or silicon-based water repellent (Patent Document 1). However, in the former method of attaching the aluminum plate with a hole, the aluminum plate itself is expensive, and there is a problem that the workability is inferior because the weight increases. On the other hand, in the latter, the water repellent effect tends to decrease over time, so there is a difficulty in durability of waterproof performance, and the nonwoven fabric has poor form stability, so it is difficult to handle when performing water repellent processing There is a problem that the processing steps become complicated.
JP-A-8-27738

  The present invention has been made in view of such a current situation, and provides a sound absorbing material that is less likely to be deteriorated in weather resistance over time, can prevent a decrease in sound absorption due to intrusion of rainwater, and can be used well outdoors. This is a problem.

The present invention achieves the above-mentioned problem, and a resin containing metal fine powder is applied to a core layer made of a nonwoven fabric having an apparent density of 0.01 g / cm ³ or more and less than 0.1 g / cm ^3. The gist is a fiber laminated sound-absorbing material characterized in that a surface material made of a fabric is laminated.

  Hereinafter, the present invention will be described in detail.

  First, the nonwoven fabric as a core material layer of the fiber laminated sound absorbing material of the present invention will be described.

  Non-woven fabric that is the core material layer is made of vegetable fibers such as cotton and hemp, animal fibers such as wool and silk, regenerated fibers such as rayon and polynosic, semi-synthetic fibers, polyester polymers, polyamide polymers, acrylics A synthetic fiber made of a fiber-forming polymer such as a polymer or a polyolefin-based polymer, or a fiber such as a composite synthetic fiber obtained by combining two or more of these fiber-forming polymers. The nonwoven fabric as the core material may be composed of a single type of fiber or a mixture of a plurality of types of fibers. In the present invention, it is preferable that the nonwoven fabric is composed of a main fiber and a binder fiber, and the constituent fibers are integrated by thermal bonding with the binder fiber, from the viewpoint of shape retention of the nonwoven fabric. In view of heat resistance, weather resistance, productivity, and the like, the fiber is preferably composed of a fiber (polyester fiber) made of a polyester polymer.

  Examples of the polyester fiber used as the main fiber include fibers made of polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, polylactic acid, or a copolymer polyester mainly composed of these.

  As the binder fiber made of a polyester-based polymer, a single component fiber made of only a polyester having a melting point lower than that of the polymer constituting the main fiber by 10 ° C. (low melting point polyester), or a low melting point polyester is at least 1 And a composite fiber formed by combining with another polymer having a melting point higher than that of the low melting point polymer. As the low melting point polyester, for example, an ethylene terephthalate unit is mainly used, and one or more kinds of co-polymers selected from isophthalic acid, adipic acid, sebacic acid, 1,4-butanediol, 1,6-hexanediol and the like are used. Polymerized component or further copolymerized oxycarboxylic acid components such as ε-caprolactone, γ-propiolactone, glycolic acid, lactic acid, or polylactic acid obtained by copolymerizing D-form and L-form lactic acid at an appropriate ratio Is mentioned.

  The single yarn fineness of the fibers forming the core layer is 15 dtex or less, preferably 1 to 10 dtex, from the viewpoint of sound absorption performance and cost.

  Further, the non-woven fabric as the core material layer may be a non-woven fabric composed of short fibers or a non-woven fabric composed of long fibers, and the production method is not limited, but to some extent It is preferable that the nonwoven fabric is made of short fibers. In the present invention, as a preferable method for producing the core material layer, a main web and a binder fiber are formed into a mixed web by a carding machine or an air lay method, and then heated and pressurized at a temperature at which the binder fiber melts to obtain a desired material. The method of making it thickness and density is mentioned.

The apparent density of the nonwoven fabric as the core layer is 0.01 g / cm ³ or more and less than 0.1 g / cm ³ , more preferably 0.02 to 0.05 g / cm ³ , and still more preferably 0.02. -0.04 g / cm < ³ >. By setting it as such an apparent density, the workability as a sound-absorbing material and a self-supporting property are ensured, and favorable sound-absorbing property can also be obtained.

  The thickness of the core material layer is appropriately selected according to the purpose of use and the like. For example, when used as a sound absorbing material attached to a soundproof wall, the core material layer is preferably 3 to 100 mm, preferably 4 to 60 mm. It is.

  In the fiber laminated sound-absorbing material of the present invention, a surface material made of a fabric formed by applying a resin containing metal fine powder to the above-described core material layer is laminated.

  Examples of the form of the fabric include a woven fabric, a knitted fabric, a non-woven fabric, and the like, but a woven fabric is preferable because the gap between the fibers can be set densely. Moreover, as a raw material which comprises a fabric, it is preferable from a productivity etc. that it is a polyester fiber. Therefore, as the fabric constituting the surface material, a woven fabric made of polyester long fibers or polyester spun yarn can be preferably used. The thickness of the fibers constituting the woven fabric is not particularly limited, but in the case of long fibers, the total fineness is about 50 dtex to 1500 dtex, and in the case of spun yarns, the cotton count is about 5 to 40 Is preferred.

  The thickness of the fabric is preferably 1/100 to 1/3, more preferably 1/60 to 1/5 of the thickness of the core material layer, from the viewpoint of sound absorption performance and cost.

  The above-described fabric is provided with a resin containing metal fine powder, but is preferably applied over at least the entire surface of one side of the fabric.

  Examples of the metal fine powder include aluminum, titanium, stainless steel, gold, silver, and platinum. It is preferable to use fine aluminum powder in consideration of little change in appearance over time and cost.

  The average particle diameter of the metal fine powder is preferably 100 μm or less, particularly preferably 20 μm or less. This is because the handling is good and the surface feeling when applied to the fabric is smooth. The content of the metal fine powder is preferably about 0.1 to 5.5 parts by mass of the metal fine powder with respect to 100 parts by mass of the resin.

  As the resin, an acrylic or polyester resin is preferably used from the viewpoint of good weather resistance. The resin may be thermoplastic or thermosetting, but is preferably a thermosetting resin because of good workability. Specifically, as an acrylic resin, a product obtained by copolymerizing an acrylic ester with a methacrylic ester, styrene, vinyl acetate or the like as a naturally dry one, and in the case of thermosetting, further mixed with a melamine resin solution Things. Examples of polyester resins include alkyd resins and unsaturated polyester resins. The alkyd resin is a thermosetting polyester resin having a polybasic acid component such as a polyhydric alcohol component such as glycerin, pentaerythritol, or ethylene glycol, and phthalic anhydride, maleic anhydride, rosin / maleic anhydride adduct, or the like. Unsaturated polyester resins are unsaturated polyesters obtained by reacting unsaturated acids such as maleic anhydride and fumaric acid, saturated acids such as phthalic anhydride and adipic acid, and polyhydric alcohol components such as propylene glycol and ethylene glycol. Is cured by adding a catalyst (peroxide) with a thermosetting resin dissolved in a monomer (such as styrene or methyl methacrylate) that is polymerized therewith.

A resin containing an appropriate amount of the above-described metal fine powder is applied over the entire surface of at least one side of the fabric. As an application method, it can be applied by a known method such as an impregnation method, a roll coating method, a knife coating method, or a calendar coating method. The amount of the resin when applied is preferably 20 to 200 g / m ² , and the thickness of the resin is preferably about 100 to 500 μm.

  The fiber laminated sound-absorbing material of the present invention is formed by laminating a surface material on one side of a core material layer. When laminating the core material layer and the surface material, the surface material is laminated so that the resin application surface side is the front side. As a specific lamination method, for example, lamination can be performed by bonding via an adhesive or a thermal bonding sheet. Specifically, a powdered hot melt adhesive or a hot melt adhesive obtained by cutting binder fibers into a length of about several millimeters is sprayed on the core material layer, and then a surface material is placed and heated and bonded. Laminate by method. Or it laminates | stacks by the method of inserting | pinching the thin nonwoven fabric (thermal-bonding sheet) which consists of a low melting fiber between a core material layer and a surface material, and heating and adhere | attaching. According to these methods, a sound-absorbing material consisting essentially of fibers can be obtained, and the working environment, recyclability, and cost are excellent.

  Moreover, the fiber laminated sound-absorbing material of the present invention may be colored as necessary. The color may be set as appropriate according to the place of use. Examples of the coloring method include a method using an original fiber, a method of imparting color by post-processing, and the like.

  The fiber laminated sound-absorbing material of the present invention can be used as a noise barrier installed as a noise countermeasure outdoors in civil engineering structures such as roads, railways, bridges, and the like, airports, various stadiums, and play facilities. For example, the soundproof wall frame and the back plate are installed so that the core layer side of the fiber laminated sound absorbing material is in contact with the back plate to form a soundproof wall. And the surface where the surface material of the fiber laminated sound-absorbing material is laminated is the sound-absorbing surface side, and is installed and used on the side where rain or the like hits.

  The present invention is a fiber laminated sound absorbing material in which a nonwoven fabric having a specific apparent density is used as a core material layer, and a surface material made of a fabric provided with a resin containing metal fine powder is laminated on one side of the core material layer. is there. In the sound-absorbing material, a surface material provided with metal fine powder is disposed on the side exposed to sunlight, that is, the surface side. Therefore, the metal fine powder reflects direct sunlight, and the resin and the core material layer It is possible to prevent the weather resistance from deteriorating and to maintain the appearance of the appearance. Moreover, since resin is provided to the surface material, it is possible to prevent rainwater from entering the sound absorbing material and maintain sound absorbing properties.

  Therefore, according to the fiber laminated sound-absorbing material of the present invention, it can be used favorably as a sound-absorbing material even in applications where it is directly exposed to wind and rain or sunlight outdoors.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, it is not limited to the following Example.

In addition, performance evaluation in the examples was performed by the following method. In addition, although there is no particular standard for sound absorption performance, it is said that a sound absorption rate of 80% at 1000 Hz is a practical level.
(1) Water repellency JIS L-1092 6.2 Water repellency test (2) Water absorption JIS L-1092 6.3 Rain test shower test) Water absorption (%) was measured according to the A method.
(3) Sound absorption rate (%)
Measures the sound absorption rate of frequencies 100Hz, 200Hz, 400Hz, 800Hz, 1000Hz, 2000Hz, 4000Hz, 6300Hz according to JIS A-1405

Example 1
The following were used as the nonwoven fabric of the core material layer. That is, a polyester-based hollow composite fiber having a three-dimensional crimp as a main fiber (Unitika Fiber Co., Ltd. <H38F> 6.6 decitex × 51 mm) and an ethylene terephthalate unit copolymerized with an ethylene isophthalate unit, a flow start temperature of 110 60:40 polyester fiber sheath-type binder fiber (<4080> 3.3 decitex x 51 mm, manufactured by Unitika Fiber Co., Ltd.), which is a composite spun using a copolyester at 0 ° C. as a sheath component (binder component) and polyethylene terephthalate as a core component A web was prepared with a card machine after blending at a ratio of (mass ratio). Next, a polyester short fiber nonwoven fabric having an apparent density of 0.04 g / cm ³ and a thickness of 45 mm is obtained by heat treatment with a thermal air-through heat treatment machine at 150 ° C. while regulating the thickness with a spacer having a thickness of 45 mm. Was used as the nonwoven fabric of the core material layer.

  As a fabric for the surface material, a 167 decitex / 35 filament polyester multifilament is used for a plain weave fabric with a warp density of 57/25 mm and a weft density of 60/25 mm. 60/40 (molar ratio) copolymer of methyl and vinyl acetate) 100 parts by weight of a resin containing 3 parts by weight of aluminum fine powder with an average particle size of 25 μm applied by a knife coating method to a thickness of 250 μm Prepared.

A heat-bonded sheet made of copolymerized polyester (“Dynax sheet” manufactured by Kureha Tech Co., Ltd., 20 g / m ² , melting point 90 ° C.) is sandwiched between the obtained core material layer and the surface-treated resin-processed fabric. Then, using a heat press machine, it was heated and pressed at a temperature of 100 ° C. for 2 minutes to obtain a fiber laminated sound-absorbing material of the present invention in which a surface material was laminated on one side of a core material layer.

Example 2
In Example 1, as a fabric for the surface material, a polyester multifilament of 280 dtex / 48 filament was used, and a plain weave fabric having a warp density of 34/25 mm and a weft density of 36/25 mm was used. Obtained the fiber lamination sound-absorbing material of this invention like Example 1. FIG.

Example 3
In Example 1, the fiber laminated sound-absorbing material of the present invention was used in the same manner as in Example 1 except that a polyester short fiber nonwoven fabric having an apparent density of 0.015 g / cm ³ and a thickness of 30 mm was used as the core material layer. Got.

Example 4
In Example 1, the fiber laminate of the present invention was used in the same manner as in Example 1 except that a polyester hollow composite short fiber having a cubic crimp of 14 dtex × 64 mm was used as the main fiber constituting the core layer. A sound absorbing material was obtained.

Example 5
In Example 1, the fiber of the present invention was used in the same manner as in Example 1 except that a polyester composite short fiber having a cubic crimp of 2.2 dtex × 51 mm was used as the main fiber constituting the core layer. A laminated sound absorbing material was obtained.

  The evaluation results of the obtained Examples 1 to 5 are shown together in Table 1.

As is clear from Table 1, the fiber laminated sound absorbing materials of Examples 1 to 5 are excellent in sound absorbing characteristics and water repellency, so that rainwater or the like is difficult to enter, and good sound absorbing properties can be maintained. it can.

  Moreover, weather resistance was evaluated on the following conditions using the obtained fiber laminated sound-absorbing material of Example 1. For comparison, in Example 1, the fiber lamination of the comparative example obtained in the same manner as in Example 1 except that an acrylic resin not containing aluminum fine powder was used as the acrylic resin applied to the fabric of the surface material. Using a sound absorbing material, the weather resistance was similarly evaluated.

(Evaluation of weather resistance)
Equipment used: Dew panel light control weather meter DPW5 type Suga Test Instruments Co., Ltd. Light source: UV fluorescent lamp (40W x 8)
Test conditions: JIS K 7350-3-1996 The following cycle defined in test mode 1 “UV irradiation at 63 ° C. for 4 hours, then no UV irradiation, exposure at 50 ° C. for 4 hours in a moisture condensed state”
Test time: 2000 hours

  As a result of evaluating the weather resistance, the fiber laminated sound-absorbing material of Example 1 was not significantly changed in appearance and there was little deterioration of the surface material. On the other hand, in the fiber laminated sound-absorbing material of the comparative example, deterioration was observed in the resin obtained by processing the surface material, and when the resin was touched by hand, the resin spilled and dropped.

Claims (4)

A surface material made of a fabric provided with a resin containing metal fine powder is laminated on a core material layer made of a nonwoven fabric having an apparent density of 0.01 g / cm ³ or more and less than 0.1 g / cm ³ . A fiber laminated sound-absorbing material. 2. The fiber laminated sound absorbing material according to claim 1, wherein the metal fine powder is a fine powder made of aluminum. 3. The fiber laminated sound absorbing material according to claim 1, wherein the fabric is a woven fabric. The nonwoven fabric constituting the core material layer is composed of a main fiber and a binder fiber, and the constituent fibers are integrated by heat bonding with the binder fiber, and the main fiber and the binder fiber are made of a polyester polymer. The fiber laminated sound-absorbing material according to any one of claims 1 to 3, wherein