JPS6345981B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a soundproofing material that reduces external noise by being installed in the space below the engine, and more specifically to a soundproofing material that overcomes the poor conditions of being located in the bottom of the engine room and has water resistance and oil resistance. The present invention relates to a soundproofing material which is excellent and has sufficiently excellent soundproofing performance and reduces external noise from a vehicle. [Prior Art] Various soundproofing materials have been proposed for automobiles, but when the source of automobile noise, especially the engine room, is the engine room, the best soundproofing measures are water and oil. There is no soundproofing material that is strong and has a sufficient soundproofing effect, and methods to prevent engine noise from propagating into the passenger compartment include installing soundproofing material on the interior side of the darts panel that separates the engine compartment from the passenger compartment; Currently, in order to prevent the propagation of vibrations through the floor panel, methods such as heat-sealing damping material to the floor panel are used. [Problems to be Solved by the Invention] However, such measures alone are still insufficient as measures against vehicle interior noise. Currently, there is a demand for soundproofing materials for engine rooms that reduce the amount of noise. [Means for Solving the Problems] Therefore, the inventors of the present invention have conducted intensive research to develop a soundproofing material that has sufficient soundproofing properties, as well as water resistance, oil resistance, and durability. A substantially non-breathable molded article obtained by heating and press-molding a bulky nonwoven fabric with a protective layer mainly made of synthetic fiber fleece laminated on at least one side to cover the lower space of an engine. The inventors have discovered that all of the above-mentioned problems can be solved by taking measures using a soundproofing material that reduces outside noise, characterized by being attached to a vehicle body, and have arrived at the present invention. In the present invention, the molded body to be attached to the countermeasure location is
It is obtained by laminating a bulky nonwoven fabric and synthetic fiber fleece on at least one side of the fabric and heat-forming the same. Bulky nonwoven fabrics used in the present invention include animal fibers such as wool, vegetable fibers such as linen and cotton, mineral fibers such as glass wool and rock wool, and acrylic, nylon, Tetron, and rayon. One or more types of synthetic fiber materials are defibrated and mixed, and a binder containing a thermosetting synthetic resin as a main component is spread to bind the fiber materials to form a bulky material. Such a thermosetting synthetic resin needs to be in an uncured state before thermoforming. It is also economically preferable to use industrial waste such as fallen cotton, waste wool, and synthetic fiber waste as the fiber material. Bulky nonwoven fabrics generally have a thickness of 8 to 50 m/m.
It is preferable that the areal density is in the range of 400 to 4000 g/m ² , and there is no problem even if several sheets are laminated and used. Synthetic fiber fleece, which is used by laminating on at least one side of a bulky nonwoven fabric to impart water resistance, oil resistance, and durability to soundproofing materials, is made of one of polyester fibers, polyamide fibers, and acrylic fibers that have a high softening point.
It is preferably made of one or more types of synthetic fibers and has a bulk density of 4 x 10 ^-4 to 8 x 10 ^-2 g/cm ³ . If the bulk density is less than 4×10 ^-4 g/cm ³ , it will be stretched during molding, causing sagging, and a sufficient protective layer cannot be provided to the molded product, and if it exceeds 8×10 ^-2 g/cm ³ This is not preferable because there is a possibility that the moldability at acute angle portions will be poor. The amount of resin contained in the synthetic resin is preferably 5 to 200 parts by weight per 100 parts by weight of the synthetic fiber. The synthetic fiber fleece is laminated on at least one side of the bulky nonwoven fabric and molded under heat and pressure, but a thermoplastic film may be interposed between the bulky nonwoven fabric and the synthetic fiber fleece. The temperature of heating and pressure molding is 150 to 250℃, and the pressure is about 1 to 150℃.
Kg/cm ³ and must be substantially non-permeable. The areal density of the molded product that can be used in the present invention is determined to be between 1000 and 6000, taking into consideration the vehicle type, usage area, and required strength range.
g/ ^m2 , and the areal density of the bulky nonwoven fabric is 1000 to 6000.
g/m ² , and laminating a thermoplastic film of 10 to 300 μm such as polyethylene or polypropylene on at least one side of the bulky nonwoven fabric, and then laminating the fleece. In addition to the case where the present invention is directly attached to a panel of an automobile, it can also be used in conjunction with soundproofing material that is attached for noise treatment. [Example] Example 30 parts by weight of recycled wool and 50 parts by weight of fallen cotton were opened and mixed to make phenolic resin powder 20 with a melting point of 150°C and a reaction temperature of 180°C.
After scattering and mixing the weight parts and making fleece with a fleece forming machine, it is passed through a heating furnace at 160℃ to a thickness of 25m/m.
A bulky nonwoven fabric with an areal density of 950 g/m ² was obtained. Bulk density: Contains 5 parts by weight of acrylic resin as solid content and adhesive binder per 100 parts by weight of fiber.
10 ^-2 g/cm ³ (thickness 10m/m, areal density 100g/m ² )
Polyester fiber fleece (commonly known as resin cotton) is sprayed with an emulsion of vinyl acetate-acrylic copolymer to give a solid content of 40 parts per 100 parts by weight of the fleece.
After spraying the solution in an amount equal to parts by weight, preheating was performed at 80° C. for 5 minutes to volatilize the water and obtain a semi-finished product that was easy to handle. Three sheets of the bulky nonwoven fabric were laminated to give an areal density of 2850 g/m ² and then on both sides.
Polyethylene films having a thickness of 70 μm were stacked, and the synthetic fiber fleece was further laminated on both sides. Thereafter, a bulky nonwoven fabric having polyethylene film and synthetic fiber fleece laminated on both sides was pressure-molded for 3 minutes under heating conditions of 180°C. The molded article had substantially no air permeability. [Test Method] The transmission loss of the soundproofing material of the example and of the soundproofing material immersed in water for 24 hours and then dried was measured using a small reverberation chamber owned by our company. 〔Test results〕

[Table] Each measurement value was the average value of 10 samples. In addition, JIS K of the soundproofing material used as an example and the soundproofing material soaked in water for 24 hours and then dried.
The elastic modulus (N/mm ² ) measured by the method of 7203 was 3.3×10 ³ N/mm ² and 3.2×10 ³ N/mm ² , respectively. [Effects of the Invention] As described above, it has been revealed that the soundproofing material according to the present invention is a soundproofing material that not only has an original soundproofing effect but also has excellent water resistance and strength.

Claims (1)

[Claims] 1 A substantially breathable fabric that covers the lower engine space in the engine compartment and is obtained by heating and press-molding a bulky nonwoven fabric with a protective layer mainly made of synthetic fiber fleece laminated on at least one side. A soundproofing material that reduces noise outside the vehicle, and is made by attaching a molded body to the vehicle body.