JP2003201657A - Sound absorbing material - Google Patents

Abstract

(57) [Summary] [Problem] To improve the sound absorbing performance and reduce the production cost by using waste fibers such as fiber waste generated in the spinning and spinning processes and cellulosic defibrated or crushed materials as main fibers. Provide a sound absorbing material. SOLUTION: A component A such as fiber waste and cellulosic defibrated material or pulverized material, a component B composed of one or more kinds of fibers selected from natural fibers and synthetic fibers, and a thermoplastic resin (fiber (Material, powder), or a resin binder composed of a thermosetting resin and defibrated / mixed with component C to produce a base material M, which is subjected to cold press molding, hot press molding, or molding to improve sound absorption performance. Mold excellent sound absorbing material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound absorbing material suitable for, for example, an insulator dash mounted on a dash panel or a floor panel, a floor carpet, etc., and particularly, by effectively utilizing fiber waste generated in a spinning process. ,
The present invention relates to a sound absorbing material that can be manufactured at low cost, has excellent sound absorbing performance, and is suitable for recycling.

[0002]

2. Description of the Related Art Usually, various soundproof materials are installed in a vehicle in order to ensure quietness during traveling. For example, as shown in FIG. 20, an insulator dash 1 is mounted on the interior side of a dash panel 1a that divides an engine room E and a vehicle compartment R, and an interior surface of a floor panel 2a in the vehicle compartment R. A floor carpet 2 is laid on the floor.

Further, inside the engine room E, there are installed a dash front insulator 3 attached to the engine room side of the dash panel 1a, a hood insulator 4 attached to the interior side of the hood panel 4a, etc. In addition to reducing the pressure, a roof trim 5 is attached to the inner surface of the roof panel 5a. Although not shown, a soundproof interior material such as a trunk trim, a luggage trim, or a wheel house trim is installed in the trunk room or the luggage room.

In this way, the vehicle compartment R, engine room E,
Alternatively, various soundproofing materials are installed in the trunk room and the luggage room. As a typical example thereof, the configuration of the insulator dash 1 mounted on the interior surface of the dash panel 1a will be described with reference to FIG. As the insulator dash 1, a two-layer structure in which a sound insulating material 7 is integrated on the surface side of a sound absorbing material 6 having sound absorbing and sound insulating properties has been conventionally known.

As the sound insulating material 7, a heavy sheet material such as a high density recycled rubber sheet or recycled vinyl chloride sheet is used. On the other hand, as a material of the sound absorbing material 6, polyester fiber such as polyethylene terephthalate (hereinafter referred to as PET) or other synthetic fiber is used as a base, and a resin binder such as a low melting point heat-fusible fiber or thermoplastic resin powder is added. Then, a base material is produced by performing a needling process or a pressing process while applying hot air, and after the base material is subjected to a heat softening treatment, cold press molding is performed, so that the sound absorbing material 6 is formed in accordance with the shape of the dash panel 1a. Molded.

[0006] As another conventional example, it is preferable to use a felt, which has fluff (which is obtained by loosening the entanglement of rags and scraps of a fiber product) as a main fiber and which is added with a binder to give moldability. In this felt, the sound absorbing material 6 is molded by cold press molding into a required shape after heat softening treatment.

In some cases, a urethane foam molded body obtained by foam molding after injecting a urethane resin liquid into the mold is used as the sound absorbing material 6.

[0008]

As described above, in the sound absorbing material 6 of the insulator dash 1 described above, in order to improve the sound absorbing property, the thickness of the sound absorbing material 6 is made thicker or the basis weight is set larger. However, increasing the basis weight leads to an increase in product cost, and if the product thickness is made thick with a constant basis weight, the density is low, so dust is likely to occur and the working environment There was a problem that it caused the deterioration of. Further, there is a problem that the moldability is deteriorated, and the portion is likely to tear at a high expansion rate portion.

Further, in the sound absorbing material 6 using the conventional non-woven fabric, if the compounding amount of the small diameter fibers is increased in order to enhance the sound absorbing property, this also leads to an increase in cost, and these fibers have a function of hardening the base material. It has been pointed out that since the base material does not exist, the rigidity of the base material is impaired.

On the other hand, when the felt is used, since the fibers of the fluff are thick, there is a problem that the sound absorbing performance is deteriorated and the weight of the product is increased. Further, when the urethane foam molded article is used, cost reduction can be expected, but there is a problem that nitrogen oxide is generated during incineration and it is also disadvantageous in recycling.

The present invention has been made in view of the above circumstances, and is a sound absorbing material that can be applied to a wide range such as an insulator dash, a floor carpet, a hood insulator, etc. The purpose is to provide a sound absorbing material that can be expected to have good performance and is suitable for recycling.

[0012]

In order to achieve the above object, the invention according to claim 1 of the present application provides a fiber waste generated in a yarn making and spinning process, a cellulosic defibrated material or a crushed material, It is characterized in that it comprises a molded body formed of a binder for binding the fiber waste and the cellulosic defibrated material or crushed material.

Here, the sound absorbing material according to the present invention has various uses such as an insulator dash, a floor carpet, a hood insulator, a dash front insulator, a roof trim and a trunk trim.

As the fiber waste generated in the yarn making and spinning steps, cotton removed in the scatting step. Cotton removed in the hair selection process, worsted process, worsted process, and worsted process.
Comb fiber scraps and noil cotton removed in the combing process. Waste fibers produced during the spinning and spinning process. A fiber that has been determined to be nonstandard by inspection during spinning and spinning. Etc. can be used.

The cellulosic defibrated material or crushed material is obtained by defibrating or crushing old newspapers, old magazines, documents, leaflets, cardboard, cardboard and the like. Chips (waste paper), cellulosic defibrated or crushed products obtained by defibrating or crushing paper scraps generated when manufacturing paper products,
It is possible to use paper chips (using new paper waste).

Next, there are thermoplastic resin type and thermosetting resin type resin binders for binding fiber waste, cellulosic defibrated material or pulverized material. Among the thermoplastic resin type, low melting point polyethylene terephthalate is used. Heat-fusible fibers such as low melting point polyester resin fibers represented by (PET), and polyethylene (hereinafter referred to as PE)
It is possible to use a resin powder such as a resin or a reactive adhesive (for example, a urethane resin adhesive). Further, in the thermosetting resin type, a thermosetting resin such as phenol resin can be used.

Next, as a method for molding a sound absorbing material, when a thermoplastic resin type is used as a binder, a raw mat is prepared from fibers and a thermoplastic resin binder (either fibrous or powdery), and hot air is blown. A sound absorbing material is obtained by heating and softening by heating or the like, and then cold press molding into a desired shape.

Further, fibers and a thermoplastic resin binder are filled in a mold, and high-temperature steam or hot air is blown into the mold from the holes formed in the surface of the mold to mold the sound absorbing material along the mold surface of the mold. You may do it.

On the other hand, when the thermosetting resin binder is used, the molding method may be such that fibers and the thermosetting resin binder are sprinkled, and then hot pressing is performed with a hot press molding die, or You may shape | mold by filling in a shaping die.

According to the sound absorbing material of the first aspect, since waste fibers such as fiber waste removed to obtain a product in the yarn making and spinning steps and the cellulosic defibrated material or crushed material are used, Since the fiber waste and the cellulosic defibrated material or crushed material are fine fibers and are inexpensive, both sound absorbing performance and low cost can be achieved.

The invention according to claim 2 of this application is characterized in that the average surface density of the molded body is in the range of 300 to 3000 g / m ² .

Here, the areal density of the molded body is 300 to 300.
The reason for setting it in the range of 0 g / m ² is that if the average surface density is less than 300 g / m ² , it is difficult to obtain a felt-like shape with a bulky feeling for obtaining a sound absorbing / sound-insulating effect.・ This is because the sound insulation effect is reduced.

On the other hand, when the average areal density exceeds 3000 g / m ² , the ventilation resistance of the base material becomes extremely high, making it difficult to heat the hot air during the production of the base material, and to cool the air inside the mold during pressing. It is also difficult to blow in, and there is a drawback that the molding tact is significantly extended.

Further, when the average surface density exceeds 3000 g / m ² , the hardness when molded to a predetermined thickness increases,
Sound absorption / insulation performance tends to deteriorate.

According to the sound absorbing material of the second aspect, by setting the areal density of the molded body within the above range, desired sound absorbing and sound insulating effects can be obtained, and hot air heating at the time of manufacturing the base material. Smooth processing of blowing cold air into the mold during processing and pressing.

According to a third aspect of the present application, the mass ratio of the fiber waste, the cellulosic defibrated material or the crushed material, which is the raw material of the molded body, and the binder is fiber swarf / cellulose defibrated material or the crushed material Material / Binder = 5-80: 5-80: 5
˜70.

If the content of the inexpensive fiber waste is less than 5%, the cost-reducing effect is small, and the number of types of fibers to be mixed increases, which complicates the preparation, so that the addition is meaningless. On the other hand, when the ratio of the fiber scraps exceeds 80%, the fiber scraps become overwhelmingly larger than the binder fibers, the cohesion is reduced, and dust generation and strength reduction are caused.

The cellulosic defibrated material or pulverized material is 5 to 8
The reason for setting the content within the range of 0% is that if the cellulosic defibrated material or pulverized material is less than 5%, the cost reduction effect is diminished, and the types of fibers to be added increase and it takes time and effort to add it. It makes no sense. On the other hand, when the cellulosic defibrated material or the pulverized material exceeds 80%, the cellulosic defibrated material or the pulverized material becomes overwhelmingly larger than the binder fiber, the cohesion is reduced, and the generation of dust and the reduction of strength cause.

Further, the reason for setting the binder within the range of 5 to 70% is that when the amount is less than 5%, the binder is insufficient.
This is because the fiber waste, cellulosic defibrated material, or crushed material cannot be collected together, which causes dust generation and strength reduction. On the other hand, if it exceeds 70%, the binder is expensive, so if the added amount is too large, the cost reduction effect due to fiber waste, cellulosic defibrated material or crushed material will not come out, and the plate thickness of the molded product will be secured. Difficult to do,
The molded product becomes too hard, which is disadvantageous in terms of sound absorption and sound insulation.

According to the sound absorbing material of the third aspect, by setting the mass ratio of the fiber waste, the cellulosic defibrated material or the pulverized material, and the binder within the above range, good strength of the molded body can be obtained. It is possible to realize an inexpensive sound absorbing material while effectively suppressing the generation of dust while maintaining it.

The invention according to claim 4 of this application is the addition of other fibers to a fiber scrap, a cellulosic defibrated material or a crushed material, and a binder, which are materials for the molded body, and the mass ratio of each material is Scrap / Cellulosic defibrated material or crushed material / Binder / other fiber = 5-80: 5-80: 5-70: 5-70
Is.

Here, other fibers include polyesters such as polyethylene (PE), polypropylene (PP) and polyethylene terephthalate (PET), synthetic fibers such as polyamide (PA) and vinylon, bamboo, hemp, cotton, kenaf, Obtained by defibrating fibrous defibrated materials made from plants such as bananas, jutes, and palms, or natural fibers such as wool, silk, animal-origin fibers typified by animal hair, clothing and fiber products It is possible to use anti-wool fibers, crushed products of various wastes or defibrated products.

The reason for setting the blending ratio of the other fibers in the range of 5 to 70% is that if the blending ratio is less than 5%, the number of fibers to be blended increases and it takes a lot of time to blend, so that there is no point in adding. On the other hand, when the content exceeds 70%, on the other hand, the amount of fiber waste, cellulosic defibrated material or crushed material, and the amount of binder added decreases, resulting in increased cost, reduced sound absorption / sound insulation performance, reduced strength, and dust generation. This is because it invites.

According to the sound absorbing material of the fourth aspect, it is possible to add various properties by adding other fibers while maintaining required items such as high sound absorbing and sound insulating performance at low cost.

The invention as claimed in claim 5 of this application is, as fiber waste, a fiber length of 2 out of the fibers obtained from cotton seeds.
It is characterized by using cotton litters having a diameter of -60 mm and a fiber diameter of 6-30 μm.

Here, the reason why the fiber length is set to 2 to 60 mm is that if the fiber length is less than 2 mm, the strength of the base material and the generation of dust are likely to occur, while the fiber length exceeds 60 mm. In addition, since the entanglement of fibers becomes excessive, it is difficult to defibrate and mix cotton, and it becomes difficult to brake the substrate, and it becomes difficult to secure the plate thickness of the molded product.

Further, the reason why the fiber diameter is 6 to 30 μm is as follows.
If the fiber diameter is less than 6 μm, the number of fibers increases, the density of the fibers increases, and the ventilation resistance of the base material increases abnormally.
It becomes difficult to heat hot air during the production of the base material and to heat and cool the air during molding. On the other hand, when the fiber diameter exceeds 30 μm, the sound absorbing / insulating performance deteriorates.

According to the sound absorbing material of the fifth aspect, by setting the fiber length and the fiber diameter of the fiber waste within the above range, the sound absorbing / sound-insulating performance and the like are increased in strength and dust is generated. It is possible to provide a base material and a product having a small amount.

The invention according to claim 6 of this application is characterized in that, as the cellulosic defibrated material or crushed material, a fibrous material obtained by defibrating or crushing waste paper or new paper end material is used. To do.

According to the sound absorbing material of the sixth aspect, by adopting waste paper or new paper scraps which can be stably obtained at low cost as the material of the cellulosic defibrated material or the crushed material, the physical properties can be improved. A stable and inexpensive sound absorbing material can be realized.
Also, instead of adding waste paper and new paper scraps as they are,
Since it is added in a state where the surface area is increased by defibrating or crushing, the sound absorption and sound insulation performance is improved.

The invention according to claim 7 of this application is a binder, which is made of polyester, polyamide, ethylene-vinyl alcohol copolymer, vinyl acetate-based or polyolefin-based material and has an average particle size of at least one. It is characterized in that a thermoplastic resin powder having a diameter of 0.1 to 1 mm is used.

Here, the average particle size of the binder is 0.1 to 1
The reason for setting the range of mm is that the average particle size is 0.1
It is because when it is less than mm, the binder particles are blown off during the hot air heating at the time of manufacturing the base material and during the hot air heating before the forming, and the binder function is not fulfilled, and the average particle diameter is 1 m.
When it exceeds m, the number of particles per unit weight decreases, and the effect as a binder becomes difficult to be obtained.

According to the sound absorbing material of the seventh aspect, by using the powder as the binder, it is possible to manufacture the base material without using sophisticated blending equipment and nonwoven fabric manufacturing equipment. For example, the substrate can be manufactured by using the steam heating method if only a simple defibrating machine and a mixer are used.

In the invention according to claim 8 of this application, the binder has a fiber diameter of 1.9 to 290 μm and a fiber length of 2 to 8
It is characterized by using a thermoplastic resin fiber having 0 mm and a melting point of 90 to 170 ° C.

The reason for using a thermoplastic resin fiber as a binder and setting the fiber diameter in the range of 1.9 to 290 μm is that the fiber diameter is less than 1.9 μm.
The number of fibers increases. Therefore, if the fiber diameter is too thin, the density of the fibers becomes high, and the ventilation resistance of the base material becomes abnormally high, making it difficult to heat the hot air during the manufacture of the base material and to heat and air cool during the molding. Further, when the fiber diameter exceeds 290 μm, the sound absorbing / sound-insulating performance deteriorates, and the number of fibers per unit weight decreases, so that the effect of the binder becomes difficult to exert.

Next, the fiber length of the thermoplastic resin fiber is set to 2
The reason for setting the range to 80 mm is that the fiber length is 2 m.
When it is less than m, the fiber waste, the cellulosic defibrated material, or the pulverized material cannot be collected together, and the strength of the base material is reduced and dust is generated. On the other hand, when the fiber length exceeds 80 mm, the entanglement of the fibers becomes excessive, which makes defibration and blending difficult, which makes it difficult to manufacture the base material and also to secure the plate thickness of the molded product. This is because it will be difficult.

Next, the reason why the melting point is limited to 90 to 170 ° C. is that if the melting point is less than 90 ° C., it cannot withstand the high temperature in the vehicle that is practically generated, and it will be deformed. Therefore, it is preferable to use a binder having a melting point higher than this. On the other hand, if the melting point exceeds 170 ° C,
This is because heating to a high temperature is required at the time of manufacturing the base material and at the time of molding, and it takes an extra time for heating, which is disadvantageous in mass production.

According to the sound absorbing material of the eighth aspect, by adopting the fibers in the above range as the binder,
It is possible to realize a sound absorbing material that has ideal strength and is also excellent in sound absorption and sound insulation performance. Further, since the binder is a fiber, it is easily entangled with fiber waste, a cellulosic defibrated material, or a crushed material, dust is less likely to be generated, and moldability is improved.

In the invention described in claim 9 of this application, the binder has a fiber diameter of 1.9 to 290 μm and a fiber length of 2 to 8
It is characterized in that a thermoplastic resin core-sheath structure fiber having a sheath portion of 0 mm and a melting point of 90 to 170 ° C. is used.

Here, the synthetic resin core-sheath structure used as the binder has a fiber diameter of 1.9 to 290 μm and a fiber length of 2 to
The reason why it is set to 80 mm and the melting point of the sheath portion in the range of 90 to 170 ° C. is the same as that of the thermoplastic resin fiber.

According to the sound absorbing material of the ninth aspect, by adopting the core-sheath fiber in the above range as the binder, it is possible to realize a sound absorbing material having high strength and excellent sound absorbing / insulating performance. Further, since the binder is a fiber, it is entangled with fiber waste, a cellulosic defibrated material, or a crushed material, and dust is less likely to be generated, so that the moldability is improved.

In addition to that, the characteristic feature of the core-sheath structure fiber is that even if it is heated to a high temperature, the sheath part only melts and the core part remains as a fiber, so that the number of fibers in the molded product should be increased. Is possible. This is advantageous in terms of sound absorption and sound insulation. Further, since the molding temperature range is widened to the higher side, the molding temperature can be tolerated to some extent and the mass productivity can be improved.

The invention according to claim 10 of this application uses, as a binder, at least one thermosetting resin selected from a phenol resin, a melamine resin, an allyl resin, a saturated polyester resin, a urea resin and an epoxy resin. It is characterized by

According to the sound absorbing material of the tenth aspect, it is possible to highly contain the dust by using the thermosetting resin as the binder. Further, since heating before molding is unnecessary, molding can be performed in a short time.

According to the eleventh aspect of the present invention, the other fiber has a fiber diameter of 1.9 to 290 μm and a fiber length of 2 to 8.
It is characterized in that any one or more of 0 mm polyethylene (PE), polypropylene (PP), polyester, polyamide (PA), and vinylon is used.

Here, the fiber diameter of the other fiber is 1.9 to 290.
The reason why the fiber diameter is less than 1.9 μm is that the density of the fibers becomes too high, and the ventilation resistance of the base material becomes abnormally high. That is, since it is difficult to heat the hot air during the production of the base material and to heat and air cool the air during the molding, there is a limit in the heating method, so the lower limit value is 1.9 μm. On the other hand, the fiber diameter is 29
If it exceeds 0 μm, the sound absorption / insulation performance deteriorates.
Also, as the fiber diameter becomes thicker, the number of fibers per unit weight decreases, and the effect of the binder becomes difficult to appear, so the upper limit value is 290.
μm.

Next, as a reason for setting the fiber length to 2 to 80 mm, if the fiber length is less than 2 mm, the strength of the base material and the generation of dust are likely to occur. Conversely, the fiber length is 80 m
When it exceeds m, the entanglement of fibers becomes excessive, which makes it difficult to defibrate and mix the fibers, which makes it difficult to manufacture the base material.
It becomes difficult to secure the plate thickness of the molded product.

Further, fibers such as polyethylene, polypropylene, polyester, polyamide and vinylon are all inexpensive and stably supplied with a designated fiber diameter and length, and are fiber scraps, cellulosic defibrated materials or crushed materials. It can be easily mixed with other materials and used as a substrate.

Further, since it has reactivity and strength which are not found in fiber waste, cellulosic defibrated material or crushed material, various properties can be imparted by adding these fibers.

According to the sound absorbing material of the eleventh aspect, the property that cannot be imparted only by the fiber waste, the cellulosic defibrated material or the pulverized material, and the binder becomes possible by adding other fibers. Furthermore, by using other fibers in the above range, strength,
Various properties can be added without compromising the required performance such as dust emission, sound absorption and sound insulation, mass productivity, and low cost.

[0061]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a sound absorbing material according to the present invention will be described in detail below with reference to the accompanying drawings.

FIGS. 1 to 6 show an embodiment in which the sound absorbing material according to the present invention is applied to an insulator dash for an automobile. FIG. 1 is a sectional view showing the structure of the insulator dash, and FIG. 2 is a sectional view of the insulator dash. FIG. 3 is a chart showing a manufacturing process, FIG. 3 is a chart showing a manufacturing process of a base material of a sound absorbing material used for the insulator dash, FIG. 4 is a schematic view showing a manufacturing process of the base material, and FIG. 5 is a manufacturing process of the insulator dash. FIG. 6 is a schematic diagram showing the steps, and FIG. 6 is a chart showing the timing at which a vacuum suction force or a pressure aerodynamic force is applied to the press molding die used for molding the insulator dash.

FIG. 7 is an explanatory view showing the structure of the sound absorbing material for preventing dust generation according to the present invention, FIG. 8 is an explanatory view of each pattern showing the sound insulation enhancing structure of the sound absorbing material according to the present invention, and FIGS. 17 is a chart view and a process explanatory view showing another embodiment of the step of molding the sound absorbing material according to the present invention, and FIGS. 18 and 19 are cross-sectional views showing modified examples adopting the laminated structure of the sound absorbing material according to the present invention. Is.

An embodiment in which the sound absorbing material according to the present invention is applied to an insulator dash will be described with reference to FIGS. 1 to 6. In FIG. 1, an automobile insulator dash 10 is mounted on a vehicle interior side of a dash panel 11 that divides an engine room E and a vehicle interior R, and a surface of a sound absorbing material 20 such as recycled rubber or recycled vinyl chloride sheet is compared. The sound insulating material 21 having a high surface area density is formed of a two-layer structure integrally laminated. The noise propagating from the engine room E to the vehicle interior side through the dash panel 11 is attenuated by the good sound absorbing performance of the sound absorbing material 20.

The sound absorbing material 20 basically uses fiber scraps removed in order to obtain a product in the yarn making and spinning processes and a cellulosic defibrated material or a crushed material as main fibers. As the fiber waste generated in the spinning process, cotton removed in the scatting process. Hair selection process,
Cotton that has been removed in the combing, downing, and downing process. Comb fiber scraps and noil cotton removed in the combing process. spinning,
Waste fibers produced in the spinning process. Use waste fibers such as those that have been determined to be non-standard products by inspection during spinning and spinning. The fiber waste preferably has a fiber length of 2 to 60 mm and a fiber diameter of 6 to 30 μm.

The cellulosic defibrated material or crushed material is obtained by defibrating or crushing old newspapers, old magazines, documents, leaflets, cardboard, cardboard and the like. Cellulosic defibrated material or crushed material obtained by defibrating or crushing chips (utilized paper), cellulosic defibrated material or crushed material generated during the production of paper chips (new paper waste material) Use).

The binder for binding the waste fibers to the cellulosic defibrated material or crushed material is a fused fiber of a thermoplastic resin (either a single fiber or a core-sheath structure), a thermoplastic resin powder, or a thermoplastic resin powder. A curable resin or the like can be used as appropriate.

The thermoplastic resin used as the binder is appropriately selected from polyester, polyamide, ethylene-vinyl alcohol copolymer, vinyl acetate resin, or polyolefin resin such as polyethylene (PE) and polypropylene (PP). good.

The thermosetting resin used as the binder may be appropriately selected from phenol resin, melamine resin, allyl resin, saturated polyester resin, urea resin, epoxy resin and the like.

Here, other fibers may be added to the main fibers such as fiber scraps, cellulosic defibrated material or crushed material, and the other fibers to be added include polyethylene (PE), polypropylene (PP) and polyethylene. Terephthalate (PE
T) and other polyesters, polyamide (PA), synthetic fibers such as vinylon, fibrous defibrated material from plants such as bamboo, hemp, cotton, kenaf, banana, jute, and palm, or wool, silk, animal hair It is possible to use natural fibers such as animal-origin fibers represented by No. 1, fluff fibers obtained by defibrating clothing and fiber products, and crushed or defibrated products of various wastes. In addition, Table 1 shows a comparison between the present invention and the conventional example.

[0071]

[Table 1]

Further, as compared with the conventional sound absorbing material composition, as shown in Table 2, by using the main fiber based on fiber waste, cellulosic defibrated material or crushed material as in the present invention, It is advantageous in terms of sound absorption performance and cost.

This means that synthetic fibers excellent in sound absorbing performance are expensive, and conversely, anti-wool fibers, which are cost-effective, tend to be inferior in sound absorbing performance because the fibers are thick. When waste, cellulosic defibrated material, pulverized material, or the like is used, the fine fibers have excellent sound absorbing performance and are inexpensive, so that both sound absorbing performance and low cost can be achieved.

[0074]

[Table 2]

Further, the average surface density of the sound absorbing material 20 is 300 to
It is preferably in the range of 3000 g / m ² .

Here, the surface density of the sound absorbing material 20 is 300 to 3
The reason for setting the range of 000 g / m ^2, the average surface density is less than 300 g / m ^2, it is difficult to felt-like with a bulky feeling to obtain a sound absorbing-sound insulation, sound absorption・ This is because the sound insulation effect is reduced.

On the other hand, when the average surface density exceeds 3000 g / m ² , the ventilation resistance of the base material is remarkably increased, making it difficult to heat the hot air during the production of the base material, and to cool the air inside the mold during pressing. It is also difficult to blow in, and there is a drawback that the molding tact is significantly extended.

Further, when the average surface density exceeds 3000 g / m ² , the hardness when molded to a predetermined thickness increases,
Sound absorption / insulation performance tends to deteriorate.

Therefore, the average surface density of the sound absorbing material 20 is set to 300.
By setting in the range of up to 3000 g / m ² , desired sound absorbing and sound insulating effects can be obtained, and at the same time, the hot air heating process at the time of manufacturing the base material and the process of blowing cold air into the mold during pressing can be performed smoothly.

Next, the manufacturing process of the insulator dash 10 will be described based on the charts of FIGS. 2 and 3 and the process explanatory diagrams of FIGS. 4 and 5.

Here, the component A refers to the fiber scraps and cellulosic defibrated material or pulverized product removed in order to obtain the product in the yarn making and spinning process, and the component B is the fiber scraps and the cellulosic defibrated material. Refers to other fibers such as synthetic fibers and natural fibers added to the product or crushed product, and the component C refers to a resin binder (which may be a fused fiber or a powder).

Then, the manufacturing process in the case where the fusion bonding fiber of the thermoplastic resin is used as the binder and the rubber sheet is used as the sound insulating material 21 will be described. First,
As shown in FIG. 4, the component A, the component B, and the component C are defibrator 3
0, and the defibrating machine 30 defibrates and mixes the cotton to the hopper 31 and then extrudes it onto the conveyor 32 in a mat shape.

Then, the material is supplied by circulatingly driving the belt 34 in the hot air oven 33, and the belt 34 pressurizes while heating with hot air, sucks with the suction device 35, cools to room temperature, and then cuts. The blade 36 cuts to a fixed size to produce the base material M.

Next, the base material M is heated with hot air, and the skin sheet S is subjected to infrared heating. Then, both of them are molded into a desired shape by cold press molding, trim pierce cut processing is performed, and then assembly is performed. Thus, the molding of the automobile insulator dash 10 is completed. At this time, the adhesiveness with the sound insulating material 21 can be enhanced by spraying a powder after the hot air heating treatment of the base material M before cold press molding, if necessary.

As shown in FIG. 5, in the heating step and the molding step of the base material M and the skin sheet S, the skin sheet S is heated and softened to a predetermined temperature by the infrared heating furnace 40, and the base material is heated by the hot air heating furnace 41. The material M is heated, and the powder 42 is sprinkled on the base material M that has been subjected to the heat softening treatment, and the peripheral edges of the skin sheet S and the base material M are held by the clamp devices 43 and 44, respectively, for cold press molding. Upper and lower molds 45,4
When the desired shape is press-molded by 6, and the outer peripheral cutting process and the piercing process are performed, the molding of the automobile insulator dash 10 shown in FIG. 1 is completed.

At this time, in order to shorten the cycle time of press molding, it is possible to apply vacuum suction force and pressure aerodynamic force to the cold press molding upper mold 45 and the cold press molding lower mold 46, respectively.

The timing at which the vacuum suction force and the pressure aerodynamic force are applied can be freely selected. This time chart diagram is shown in FIGS. What is shown in FIG.
The vacuum suction from the upper mold 45 and the compressed air start and stop timings from the lower mold 46 are controlled to be synchronized. Therefore, the vacuum suction force applied to the upper mold 45 can secure the plate thickness of the product, and the air can be supplied from the lower mold 46 to accelerate the cooling time.

Further, as shown in FIG. 6 (b), the lower mold 46 first exerts a vacuum suction force, and thereafter, the upper mold 45 simultaneously suctions a vacuum and the lower mold 46 exerts a pneumatic force. Then, the vacuum suction force from the first lower mold 46 can increase the adhesive strength between the sound insulating material 21 and the sound absorbing material 20.

Next, as shown in FIG. 6C, the upper mold 45
By applying a vacuum suction force from the lower mold 46 to the compressed air from the lower mold 46 to secure the plate thickness of the product, shorten the cooling time, and improve the mold release property of the product.
The upper mold 45 to apply compressed air to raise the mold release property, or to apply a vacuum suction force to the lower mold 46.
The product may be adsorbed to the lower mold 46, and it is preferable that the product is vacuum-adsorbed again and then depressurized from the lower mold 46 to be released from the mold.

Further, as shown in FIG. 6 (d), the vacuum suction force is continuously continued to the upper mold 45 in accordance with the mold opening timing, and the product is moved upward while the lower mold 46 also exerts the aerodynamic force. The mold may be opened while being sucked and held by the mold 45, and thereafter, the upper mold 45 may be subjected to pressure aerodynamic force to be released from the mold.

Thus, the vacuum press force and the aerodynamic force are freely applied to the cold press molding upper and lower molds 45 and 46,
It is possible to shorten the molding time and smoothly remove the product from the mold.

Next, FIG. 7 shows the fiber waste used in the present invention,
When a crushed product of a waste material is added to a component such as a cellulosic defibrated material or a crushed material, dust is likely to be generated from the base material M or the molded product. As shown in FIG. 7A, the nonwoven fabric 50 (10 to 300 g / m ² ) is laminated on at least one surface of the base material M.

In this lamination method, heat fusion, low melting point powder, hot melt, needle punch, etc. can be used, and the base material M and the non-woven fabric 50 are laminated at a high temperature at the time of molding by laminating without adhering or only as temporary fixing. And may be integrated by fusion.

As shown in FIG. 7B, a film 51 may be laminated on at least one side of the base material M. The film 51 may be adhered by heat fusion, powder fusion, or hot melt fusion. Etc. can be used, and they may be heat-sealed at a high temperature at the time of molding the base material M by stacking them without adhering them or by only temporarily fixing them.

Further, as shown in FIG. 7 (c), a laminated body in which the nonwoven fabric 50 and the film 51 are laminated may be laminated on the surface of the base material M. This non-woven fabric 50 prevents the film 51 from tearing, and the non-woven fabric 50 has an area density of 10 to 10.
It is about 300 g / m ² , and the method for adhering the film 51 is the same as in FIG.

Further, different treatments may be applied to the front surface and the back surface of the base material M, respectively.

Next, FIG. 8 shows a structure in which the sound insulation function is reinforced on the base material M. As shown in FIG. 8A, it is used as a high-density surface layer 52 and laminated on the base 53. The high-density surface layer 52 is set to a high density by increasing the content of the binder component, and the resin may be impregnated in place of the binder to increase the density.

As shown in FIG. 8 (b), a non-venting layer 54 may be laminated and integrated on the base material M on the surface which becomes the interior surface of the product. The non-venting layer 54 may be a synthetic resin sheet. ,
The thickness of vinyl chloride sheet, foamed resin sheet, rubber sheet, metal sheet, etc. is 10 μm or more. Further, as shown in FIG. 8C, the panel-side surface layer 55 and the base 53 having a low binder content and a low density may be laminated.
Incidentally, the various laminated structures shown in FIG. 7 also have a function of enhancing sound insulation in addition to the dust prevention structure.

Next, the manufacturing process of various modifications of the sound absorbing material according to the present invention will be described.

FIG. 9 is similar to the above-described embodiment in the manufacturing process of the base material M, except that the breathable skin is laminated and integrated. In this case, the breathable skin can be superposed on the base material M and integrally heated by hot air heating. Next, FIG. 10 shows a method of preliminarily integrating the base material M when the breathable skin is laminated.

Further, FIG. 11 shows a case where a thermoplastic resin binder is used as the binder, but a product is obtained by directly laminating the skin without going through the state of the base material M. As shown in FIG. The upper and lower molds 60, 61 are filled with the defibration / mixture of component A, component B, and component C, and after the mold is clamped, steam or hot air is blown to melt the binder inside and directly mold. At this time, the breathable skin may be subjected to infrared heating and set between the upper and lower molds 60, 61 for molding.

Next, FIGS. 13 to 15 are charts of a manufacturing process in which a thermosetting resin binder is used as a binder for binding fiber waste, cellulosic defibrated material or crushed material, and the manufacturing process shown in FIG. In the process, a base material is manufactured by mixing a component A such as fiber waste, a cellulosic defibrated material, or a crushed material, a reinforcing component B such as synthetic fiber or natural fiber, and a thermosetting resin binder, and if necessary, After spraying the powder, it can be overlaid with the skin layer, molded into a desired shape with a hot press molding die, trim pierced, and then subjected to an assembly process to form a product.

Further, as shown in FIG. 14, the skin layers can be preliminarily stacked and integrated at the time of manufacturing the base material M. As shown in FIG. 15, the skin layers are laminated without passing through the base material state. You can also

Next, FIG. 16 is a process chart diagram for manufacturing a sound absorbing material by adding a cotton blending process to the chip urethane production line. The component A such as fiber waste, cellulosic defibrated material or crushed material and the reinforcing fiber are shown. After measuring the component B which is the component B and the component C which is the thermoplastic resin binder, mixing and defibrating,
As shown in FIG. 17, the defibrated / mixed fiber is filled in the mold 70, and high-temperature steam or hot air is blown into the mold 70 while being pressurized to a predetermined pressure by the pressure plate 71, and the block B is taken out from the mold 70 to have a constant thickness. Then, the base material M is manufactured by performing a slicing process on the substrate and further cutting the periphery.

It is also conceivable to subject the base material M to various surface treatments. For example, water on at least one side of the substrate M,
Treat with solution. If the timing of the treatment at this time is immediately before the hot air treatment for manufacturing the base material M or immediately before the hot air heating in the molding step, the drying step becomes unnecessary.

Examples of the treatment chemicals other than water are as follows.

<Synthetic adhesives> -Various organic or aqueous adhesives-Emulsion and emulsion-based adhesives <Adhesives and polysaccharides derived from natural substances> (Seaweed extract) Example) Agar, Carrageenan Example) Alginic acid, Sodium alginate and alginate compounds (plant extracts) Ex) Starch, amylopectin, pectin, gum arabic Ex) Locust bean gum, guar gum Ex) Sugars such as sugar and glucose (animal protein) Ex) Gelatin, casein (Cellulose) Ex ) Carboxymethyl cellulose Example) Methyl cellulose and other chemically modified cellulose (others) -Tackifier (tackifier resin) -Rosin (pine resin) compound-Amylose, pectic acid, xylan, alginic acid fiber, protein fiber

As a method for treating the chemical, spray, brush paste, coating roll, dipping, etc. can be used. When the base material M contains a component having a hydrophilic group in its chemical structure, water or an aqueous solution is used. Hydrogen bonds are bonded to the surface of the base material M to fix the dust component.

When performing the chemical treatment, the effect of the chemical treatment can be enhanced by rubbing the surface of the base material M with a roll that is not synchronized with the base material conveying speed.

Further, at least one surface of the base material M may be treated with hot melts, for example, by covering the surface with a web-like (web-like) or mesh hot melt to lower the air permeability. Suppresses dust generation. The one having a basis weight of 10 to 150 g / m ² is used.

The resin powder is sprinkled and then heat-treated to cover the surface of the base material M with the crushed powder to suppress the generation of dust. The hot melt, the powder is a low melting point polyester, polyamide, ethylene-vinyl alcohol copolymer, vinyl acetate-based or polyolefin-based,
A melting point of 100 to 170 ° C. is recommended. Alternatively,
The liquid hot melt is applied in the form of threads on the surface of the base material randomly or in a mesh to suppress dust.

At any time during the production of the base material M, water, an aqueous solution or a chemical agent is sprayed on the cotton and cellulosic defibrated material or pulverized material. Since the whole of the cotton and the cellulosic defibrated material or the pulverized material is treated, the whole of the substrate from the surface to the inside is treated, so that the effect of suppressing dust is high. Since the dust component is adsorbed on the fibers by the spraying process, it is possible to suppress dust generation in the manufacturing process of the base material. When the chemical structure of the fiber or dust component contains a hydrophilic group, and the drug is aqueous, the dust component is strongly adsorbed to the fiber by hydrogen bonding. As the treatment chemical, the same one as described above is used.

Next, specific examples of the composition and constitution of the base material M will be described.

As shown in FIG. 18, when the surface layers 57 are laminated on both sides of the sound absorbing layer 56, the sound absorbing layer 56 is a fiber waste / fiber diameter 6 to 30 μm, a cellulosic defibrated material or a crushed material, PET / 290 μm or less, PET binder = 5
80: 5-80: 5-70: 5-70, total thickness 5-60
mm, density 0.005-0.6 g / cm ³ . Further, as the surface layer 57, PET / 290 μm of 290 μm or less
The following PET binder = 0 to 95: 5 to 100, 12 to
The areal density is 300 g / m ² .

As the synthetic fiber to be added, the fiber diameter is 1.9 to 290 μm (preferably 60 to 150 μm).
m), fiber length 2 to 80 mm (preferably 30 to 74 m)
m) and the binder (in the case of fiber), the fiber diameter is 1.9 to 2
90 μm (preferably 20 to 150 μm), fiber length 2
-80 mm (preferably 30-74 mm), and as materials, polyethylene (PE), polypropylene (PP),
Synthetic fiber made of polyester such as polyethylene terephthalate (PET), polyamide (PA), vinylon and the like. The melting point is preferably in the range of 90 to 170 ° C.

Not only the binder fiber made of a single material,
A fiber having a core-sheath structure, for example, a structure in which the core is PP and the outer side is PE, or a structure in which the core is PP and the outer side is PET may be used.

As the binder (resin powder), polyethylene (PE), polypropylene (PP), polyester such as polyethylene terephthalate (PET), polyamide (PA), ethylene-vinyl alcohol copolymer (E
Not limited to a resin powder made of VA) or the like, or a powder made of a single material, a powder made of a blend polymer may be used, or powders made of different materials may be blended. It is preferable that the average particle size of the powder is in the range of 0.1 to 1 mm.

For the overall binder, it is possible to use a fibrous binder and a powdery binder together.

Next, Tables 3 to 11 show various compositions of the sound absorbing layer 56 and the surface layer 57. As shown in Table 3, the surface layers 57 on both sides have a high binder content and a sandwich structure. As a result, the rigidity of the product can be increased.

[0120]

[Table 3]

Further, as shown in Table 4, the surface layers 5 on both sides are
7 is reduced to a bulky flexible non-woven fabric to impart sound absorbing properties to the surface layer 57 itself, and the sound absorbing layer 56 is mas
s. The sound absorbing layer 56 has a soft touch on the vehicle body panel with a composition for improving the sound insulating property by using the surface layer 57 as a spring, so that the sound insulating performance is further enhanced.

[0122]

[Table 4]

In the constitution shown in Table 5, the sound absorbing layer 56 has a composition for increasing the sound absorbing property by increasing the compounding amount of the fiber waste and the cellulosic defibrated material or the pulverized material, and the sound insulating property is improved by reducing the spring constant of the base material M. Can be expected.

[0124]

[Table 5]

Further, in Table 6, the blending amount of the synthetic fiber is increased to enhance the strength of the base material. In Table 7, the sound absorbing layer 5 is blended.
The amount of binder in No. 6 is reduced to the utmost and a low spring is used to improve sound insulation.

[0126]

[Table 6]

[0127]

[Table 7]

In Table 8, if the amount of the binder in the sound absorbing layer 56 is increased and the composition is compatible with parts requiring high heat distortion resistance, such as a ceiling, if a crystalline heat-fusible fiber is used for the binder, heat resistance will be improved. Useful for improving deformability.

[0129]

[Table 8]

In Table 9, the rigidity strength of the base material M and the product can be increased by adding natural fibers to the sound absorbing layer 56 and using a hard fiber such as bamboo fiber in a composition for diversifying the physical properties of the base material M. .

[0131]

[Table 9]

As shown in Table 10, natural fibers are added to the surface layer 57 so as to diversify the physical properties of the base material M.
If a hard fiber such as bamboo fiber is used, the sandwich structure is highly effective in increasing the rigidity.

[0133]

[Table 10]

Further, as shown in Table 11, the sound absorption can be improved by reducing the basis weight of the surface layer 57 to the utmost and increasing the basis weight of the sound absorbing layer 56.

[0135]

[Table 11]

As shown in FIG. 19, the non-woven fabric on the indoor side has a high binder composition and the panel side has a low binder composition.
Each of the three layers can have an individual role.

At this time, the inner surface layer 58a has a thickness of 60 μm.
m, PET / 20 μm, binder = 10: 90, areal density 150 g / m ² , and increase the amount of binder to form a hard high-density layer, eliminating the need for a sound insulating material.

Further, the panel side surface layer 58b is 60 μm.
m, PET / 20 μm, binder = 95: 5, areal density 2
At 50 g / m ² , it is recommended to reduce the amount of binder to make it fluffy and soft touch the panel.

[0139]

As described above, the sound absorbing material according to the present invention does not use PET fiber or anti-wool fiber as the main fiber of the sound absorbing material, and the waste fiber removed to obtain the product in the spinning and spinning process. In addition, since the defibrated material or pulverized material of cellulose is used, the recycled fiber can be used at a low price, the sound absorbing performance can be improved, and the cost is about 1/4 of that based on the synthetic fiber. It has an effect that it can be reduced, the sound absorbing performance is excellent, and the cost can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment to which a sound absorbing material according to the present invention is applied and showing a structure of an automobile insulator dash.

FIG. 2 is a chart showing a manufacturing process of the automobile insulator dash shown in FIG.

FIG. 3 is a chart showing a manufacturing process of a base material in the manufacturing process chart shown in FIG. 2;

4 is an explanatory diagram of a configuration of the chart shown in FIG.

FIG. 5 is an explanatory diagram showing a manufacturing process for manufacturing an insulator dash from a base material and a skin sheet.

FIG. 6 is a time chart of the mold in the manufacturing process shown in FIG.

FIG. 7 is an explanatory view showing a dust generation preventing structure of a base material used for the sound absorbing material according to the present invention.

FIG. 8 is an explanatory view showing a sound insulation enhancing structure of a base material used for the sound absorbing material according to the present invention.

FIG. 9 is a chart showing another embodiment of the step of molding the sound absorbing material according to the present invention.

FIG. 10 is a chart showing another embodiment of the step of molding the sound absorbing material according to the present invention.

FIG. 11 is a chart showing another embodiment of the process of molding the sound absorbing material according to the present invention.

FIG. 12 is an explanatory view showing a forming process of the base material.

FIG. 13 is a chart showing another embodiment of the step of molding the sound absorbing material according to the present invention.

FIG. 14 is a chart showing another embodiment of the step of molding the sound absorbing material according to the present invention.

FIG. 15 is a chart showing another embodiment of the process of molding the sound absorbing material according to the present invention.

FIG. 16 is a chart showing another embodiment of the process of molding the sound absorbing material according to the present invention.

FIG. 17 is a process explanatory view of the chart shown in FIG.

FIG. 18 is a cross-sectional view showing a mixed composition of a base material in the sound absorbing material according to the present invention.

FIG. 19 is a cross-sectional view showing a compounding composition of a base material in the sound absorbing material according to the present invention.

FIG. 20 is an explanatory diagram showing installation locations of vehicle soundproofing materials.

FIG. 21 is a cross-sectional view showing the structure of a conventional automobile insulator dash.

[Explanation of symbols]

10 Automotive Insulator Dash 11 Dash panel 20 sound absorbing material 21 Sound insulation material 30 defibrator 31 hopper 32 conveyor 33 hot stove 34 belt 35 suction device 36 cutting blades 40 infrared heating furnace 41 Hot air heating furnace 42 powder 43,44 Clamping device 45 Cold press upper mold 46 Cold Press Molding Lower Mold 50 non-woven fabric 51 films 52 High-density surface layer 54 Non-breathable layer 55 Panel side surface layer 56 sound absorbing layer 57 surface layer 58a Indoor surface layer 58b Panel side surface layer 60 Upper mold 61 Lower mold Type 70 71 Pressure plate M base material S skin sheet

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tatsumi Onishi             Nissan, Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan             Inside the automobile corporation (72) Inventor Tsunemasa Shiotani             3316 Miyayama, Samukawa-cho, Takaza-gun, Kanagawa Prefecture             Industry Co., Ltd. (72) Inventor, Koichi Nemoto             3316 Miyayama, Samukawa-cho, Takaza-gun, Kanagawa Prefecture             Industry Co., Ltd. F term (reference) 2E001 DF04 GA84 HE00 HF15 JC03                       JC06 JD00 JD02 JD04                 3D023 BA03 BB21 BD12 BE04                 4L047 AA08 AA14 AA16 AA21 AA23                       AA27 AA28 AB02 AB06 BA09                       BA13 BB02 BB03 BB04 BB06                       BB07 BB09 BC03 BC06 BC07                       BC10 BC11 CB03 CB09 CC09                       CC10

Claims (11)

[Claims] 1. A molding formed by using as a raw material a fiber waste generated in a yarn making or spinning process, a cellulosic defibrated material or a crushed material, and a binder for binding the fiber waste and the cellulosic defibrated material or the crushed material. A sound absorbing material characterized by being composed of a body. 2. The average surface density of the molded body is 300 to 30.
2. It is within the range of 00 g / m ^2.
Sound absorbing material described in. 3. The mass ratio of the fiber waste, the cellulosic defibrated material or the crushed material, and the binder, which are the raw materials of the molded body, is such that the fiber trash / the cellulose defibrated material or the crushed material / binder = 5.
It is 80: 5-80: 5-70, The sound-absorbing material of Claim 1 or 2 characterized by the above-mentioned. 4. A fiber scrap, a cellulosic defibrated material or a crushed material, which is a material of the molded body, and another fiber added to a binder, and the mass ratio of each material is such that a fiber scrap / cellulose defibrated material or a crushed material / Binder / other fiber = 5-80: 5-80:
5 to 70: 5 to 70, The sound absorbing material according to claim 1 or 2, wherein 5. As the fiber scraps, among the fibers obtained from cotton seeds, cotton litters having a fiber length of 2 to 60 mm and a fiber diameter of 6 to 30 μm are used.
The sound absorbing material according to any one of 1. 6. The fibrous material obtained by defibrating or crushing waste paper or new paper scraps is used as the cellulosic defibrated material or crushed material. Sound absorbing material described. 7. The binder is made of one or more materials selected from polyester, polyamide, ethylene-vinyl alcohol copolymer, vinyl acetate and polyolefin, and has an average particle size of 0.1 to 1 mm. A thermoplastic resin powder is used, and the thermoplastic resin powder is used.
The sound-absorbing material according to any one of 1 to 6. 8. A binder having a fiber diameter of 1.9 to 290.
The sound absorbing material according to any one of claims 1 to 6, wherein a thermoplastic resin fiber having a micrometer, a fiber length of 2 to 80 mm, and a melting point of 90 to 170 ° C is used. 9. A fiber diameter of 1.9 to 290 as a binder
μm, fiber length 2 to 80 mm, sheath melting point 90 to 170 ° C.
7. The sound absorbing material according to claim 1, wherein the thermoplastic resin core-sheath structure fiber is used. 10. A binder comprising at least one thermosetting resin selected from a phenol resin, a melamine resin, an allyl resin, a saturated polyester resin, a urea resin and an epoxy resin. The sound absorbing material according to any one of 1. 11. A fiber diameter of 1.9 to 290 as the other fiber.
μm, polyethylene having a fiber length of 2 to 80 mm (P
E), polypropylene (PP), polyester, polyamide (PA), and vinylon are used in one or more kinds, The sound absorbing material according to any one of claims 4 to 10.