JPS6046012B2 - Method for producing soundproofing material for automobile floors with excellent waterproof properties - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a soundproofing material for automobile floors with excellent waterproof properties, and more specifically, to a method for manufacturing a soundproofing material for an automobile floor surface having excellent waterproof properties. An adhesive that can form a discontinuous closed cell layer is used as an adhesive with the system sheet, and a discontinuous closed cell layer L-,...''' is applied to the areas where strong pressure is not applied. -: ni'lr--nTr"ι, Suga-ryo■1.1, ↓cho4
--↓←Nokayano, 1↓By applying strong pressure, the adhesive is sufficiently impregnated deep inside the bulky nonwoven fabric,
This suppresses foaming and forms a continuous elastomer.

The adhesive foam layer with discontinuous closed cells prevents water from seeping in from damage that occurs in the film layer and sheet layer, and water from seeping through the cut edges of the punching is prevented by using a compressed bulky nonwoven fabric or an elastomer formed on the needle felt part. The present invention relates to a method for manufacturing a soundproofing material for automobile floors that has excellent waterproofness that can be easily prevented by layers. BACKGROUND ART Conventionally, flooring materials in the interior of automobiles have been widely used as a combination of simply placing a waterproof sheet such as a PVC sheet on top of needle felt or carpet.

However, such a method has insufficient sound absorption and insulation properties, and cannot contribute sufficiently to preventing noise inside the vehicle interior.In addition, if the PVC waterproof sheet is displaced, water can easily infiltrate from the ends of the sheet. However, there are problems such as contamination of felts and carpets, and a decrease in sound absorption due to water content in the felts, and improvements have been desired. The inventors of the present invention have completed the present invention as a result of intensive research in view of the above circumstances, and the purpose of the present invention is to not only provide excellent sound absorption and insulation properties but also to To provide a method for producing a soundproofing material for automobile floors, which has extremely good waterproof properties, including corrosion resistance, mildew resistance, and elastic recovery rate of felts, and which does not reduce sound absorption and insulation properties. It is about providing.

That is, the gist of the present invention is that when laminating a thermoplastic film with a bulky nonwoven fabric or needle felt as a core and a sheet layer made of a filler, rubber, and/or thermoplastic resin, closed cells are formed between each layer of the laminate. The first step is to apply a layer-forming adhesive and then apply the laminated adhesive, and when the laminated adhesive is pressure-molded with or without heating, the vicinity of the punching blade for punching into the desired shape is appropriately A second step of deeply impregnating the inside of the pressed bulky nonwoven fabric or needle felt portion with an adhesive that can form a closed cell layer by pressing the adhesive layer to form a closed cell layer, and at the same time foaming the adhesive layer of the laminate. A third step of punching out the remaining parts to obtain a molded body of a desired shape is a method for manufacturing a soundproofing material for an automobile floor surface having excellent waterproof properties.

The present invention comprises a cushion layer made of a sound-absorbing bulky nonwoven fabric or needle felt, and a waterproof sheet layer and film layer, each of which is already known.

However, in the conventional specification, the cushion layer was temporarily adhesively attached to the floor surface, and the waterproof layer was simply placed on top of it, which caused the waterproof layer to shift from the bottom of the cushion layer and from the edge of the cushion layer. In some cases, there is nothing that can be done against water coming from above. Also, a higher level of livability. It cannot live up to its aesthetic appeal. According to the present invention, a bulky nonwoven fabric or needle felt with excellent sound absorbing properties is sandwiched between a lower waterproof layer made of a thermoplastic film and an upper layer having sound insulation properties made of a rubber type or thermoplastic sheet! The two layers are pasted together with an adhesive layer that can form a discontinuous closed cell layer. Alternatively, an elastomer can be formed by applying strong pressure during foaming and allowing the adhesive to penetrate into the center of a bulky nonwoven fabric or needle felt, thereby completely preventing water from seeping in from the edges. This makes it possible to provide a soundproofing material with excellent mold resistance, elastic recovery rate, sound absorption, and livability.

The thermoplastic film that can be used in the present invention is attached to the lower layer of bulky nonwoven fabric or needle felt, and may be a thermoplastic film made of vinyl chloride, polyethylene, polyprene, etc., and a thickness of 100 to 500 p is sufficient.

The bulky nonwoven fabric formed in the center layer of the present invention is mainly composed of one or more types of discontinuous fiber materials of animal origin, vegetable origin, mineral origin, and synthetic resin, and a binder in the form of ribs made of thermosetting resin. can be obtained by a method for manufacturing a bulky nonwoven fabric that is known per se, but it is important that the binder is almost cured to have sound absorbing and cushioning properties.

The bulky nonwoven fabric in this state generally has a thickness of 8 to 50 m. 1rrL, and the areal density is 400 to 400
It is preferably in the range of 0q17T1. There is no need for any special needle felt, and it may be obtained by adding a needle punch to a fleece made of one or more of animal, vegetable, mineral, or synthetic resin materials using a conventional method. The sheet layer of rubber and/or thermoplastic resin adhered to the upper layer of the present invention may be any rubber selected from natural rubber, synthetic rubber, recycled rubber, etc. and/or thermoplastic composite such as vinyl chloride resin, bituminous material, etc. A filler selected from conventionally known fillers such as calcium carbonate, asbestos, talc, and magnesium carbonate is mixed into the resin, and after kneading it is mixed into a flat or patterned sheet using a calendar roll or embossing roll. It can be used as a physical object.

There is no problem in adding other conventionally known additives such as anti-aging agents. If the sheet layer is desired to have decorative properties, the surface may be embossed or painted. The thickness of these sheet layers is 0.5-3m1m. degree is preferred. In the present invention, the adhesive that can be used to adhere each layer must be able to exhibit an adhesive effect and form discontinuous closed cells, and at the same time have properties as an elastomer. It's good to have something to say.

As the resin component of the adhesive, a urethane resin type is most preferable, but an elastomer type adhesive such as natural rubber, recycled rubber, styrene-butadiene, neoprene, and nitrile, or a thermosetting elastomer type adhesive such as a nitrile-phenol resin may be used. It's okay. Urethane resin adhesives include isocyanate prepolymers such as diisocyanate, triisocyanate and polyol components such as polyester polyols and polyether polyols, or natural rubber,
It may be any conventionally known material that can be obtained by disposing a rubber component such as neoprene or nitrile rubber, and there are no particular limitations. These adhesives may be of a solvent type, in which they are dissolved in an appropriate proportion of a solvent, or may be of an emulsion type, in which they are dispersed in water. A method for foaming the adhesive layer is a method using carbon dioxide gas generated by the reaction between carboxyl polyester and isocyanate or the reaction between water and isocyanate;
A method of adding a volatile solvent, a method of adding and mixing a blowing agent that generates nitrogen gas when decomposed by heating, etc. can be used, but a method using a blowing agent that generates nitrogen gas is preferable.

As the foaming agent added to the adhesive, for example, as a foaming agent that decomposes upon heating to generate nitrogen gas, an organic foaming agent that generates fine closed cells is preferable, such as N●N-dinitrosopentamethylenete. Examples of blowing agents include thoramine; N●N-dimethyl-dinitrosoterephthalamide; diazoaminobenzene; azobisisobutylnitrile; azocyclohexylnitrile; and azodicarbonamide. A foaming aid may also be used in combination to assist the decomposition of the foaming agent and lower the decomposition temperature. Examples include salicylic acid, phthalic acid, urea, ethanolamine, and zinc white. These foaming agents and auxiliary agents may be added and mixed in an amount of 2 to 100 parts by weight per 100 parts by weight of the resin component of the adhesive. Other additives such as catalysts and foam stabilizers may also be added. In the first step of the method of manufacturing a soundproofing material for automobile floors with excellent waterproof properties according to the present invention, the adhesive containing a foaming agent is applied by air spray or airless spray. Although it is common, means such as a curtain flow coater may also be used.

In the case of a two-liquid type, it is preferable to use a two-head gun or the like. The surface to which the adhesive is applied may be a film layer or a sheet layer, a bulky nonwoven fabric surface, or a needle felt surface. For example, after applying an adhesive to a sheet layer, a bulky nonwoven fabric is laminated, and after applying an adhesive to the upper surface of the laminated bulky nonwoven fabric, a film layer is laminated. The films, sheets, bulky nonwoven fabrics, or needle felts to be laminated may be laminated after being cut, or may be sequentially laminated and pasted as long sheets, laminated and pasted, and then cut. The coating amount of these adhesives is approximately 100 to 10
Approximately 00f1bo is preferable. In the second step of heating and press forming, the heating temperature condition is about 80 to 140°C and the pressure condition is about 10 to 100 k91 cIt, and the vicinity of the punching blade of the desired shape is strongly pressed to an appropriate width, for example, about 30 to 80 rr LIrrL. Approximately 2 to 2
It is sufficient to perform powder heating and pressure molding.

The portions that are not pressed strongly require sufficient cushioning properties, so there is little need for pressure, and it is sufficient to apply heat to the adhesive layer. However, when using a foaming agent that foams when heated, heating is required, but when foaming is performed using water, a carboxyl group-containing compound, or a low boiling point volatile solvent, heating is not required and compression molding alone is sufficient. be.
However, in this case, it is necessary to pay sufficient attention to pot life. In the third step, the portion that has been strongly pressed using a conventionally known press machine may be punched out into a desired shape using a conventional method.

Since the molded product obtained by the above process is punched into the desired shape, it can be simply placed on the floor of the car, or it can be attached to a rising part by attaching a mounting bracket to the high-pressure part, or fixed to the floor. It can be easily attached to any shape of floor surface.

EXAMPLES Below, embodiments of the present invention will be illustrated with reference to Examples, and will be provided for a more detailed understanding of the present invention. Naturally, the present invention is not limited to the following examples.

EXAMPLE 10 parts by weight of recycled tire rubber, 150 parts by weight of calcium carbonate, and 5 parts by weight of asbestos were kneaded using a mixing roll, and then a sheet material having a thickness of 2 ml/rn was obtained using a calender roll.

3 weight parts of recycled wool and 5 weight parts of fallen cotton are mixed with Kansen, melting point 140
20 parts by weight of phenolic resin powder with a reaction temperature of 170°C was sprinkled and mixed at 170°C to form a fleece in a fleece forming machine, and then passed through a heating oven at 190°C to fully harden the scattered and mixed phenolic resin, giving it rich cushioning properties. Thickness: 137n
．． ITrL, a bulky nonwoven fabric with a surface density of 800yId was obtained.

A two-component proportional pressure-feeding system in which liquid A consisting of a metaphenylene diisocyanate-based solvent-free polyisocyanate and liquid B consisting of a polyol, blowing agent, catalyst, and foam stabilizer are placed on a commercially available vinyl chloride film with a thickness of 270μ. Using air spray, set the mixing ratio of liquid A/B to 3:10 in terms of volume, and apply a coating amount of 3.
10y1d, and then the bulky nonwoven fabric was laminated and pasted.

Furthermore, the above-described two-component adhesive was applied onto the bulky nonwoven fabric in a coating amount of 270 yI, and then the sheet-like material was laminated and pasted. The width of the peripheral part is 307n. I7TL1 A pair of upper and lower molds with a convex part with a diameter of 100m1m that can be used for zero-breathing is used almost at the center, heating conditions are 105℃, and pressure conditions are 30kgIc! Heat forming was performed for about 5 minutes as t.

The zero-breath portion of the molded product was punched out using a punching blade to obtain a substantially rectangular sound-insulating material for automobile floors having a diameter of 80 m and a 1 m punched portion in the center. A knife was used to cut the vinyl chloride film surface of the obtained soundproofing material to a length of 200 mIm. After making scratches in 4 places, it was immersed in water for about 3 hours.

Claims (1)

[Claims] 1. Adhesion that can form a closed cell layer between each layer of the laminate when laminating a thermoplastic film with a bulky nonwoven fabric or needle felt as a core and a sheet layer made of filler, rubber and/or thermoplastic resin. In the first step of laminating and pasting after applying the agent, when the laminated and pasted product is pressure-molded with or without heating, the vicinity of the punching blade for punching into the desired shape is pressed to an appropriate width to form closed cells. A second step is to deeply impregnate the compressed bulky nonwoven fabric or needle felt portion with an adhesive capable of forming a layer, and at the same time foam the adhesive layer of the laminate.The pressed portion is punched out into a desired shape. A method for producing a soundproofing material for an automobile floor surface having excellent waterproof properties, comprising: a third step of obtaining a molded body.