JPH0459238A - Sound insulation material using coating agent and its manufacture - Google Patents

Abstract

PURPOSE:To obviate the preheating process for molding by applying thermoplastic resin or a mixture of thermoplastic resin and filler to a molding die, then laminating a unmolded or a molded bulky felt on the coat and closing the molding die to make a molded product under pressure. CONSTITUTION:The thermoplastic resin is applied to a molding die for cold press in the thickness of 1 to 10kg/cm<2> using an applicator. A molded or an unmolded bulky felt is laminated on the surface coated with the thermoplastic resin. Then a top force of a die is allowed to descend and the resin is molded under appropriate pressure for an appropriate time with the felt. The thermoplastic resin applied to the mold is laminated to acoustic layers 2, 2' of bulky felt or polyurethane foam together with filler sprayed to an area between the mold and the resin. Thus an excellent sound insulation function is ensured across the sound insulation material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sound insulating material using a coating material as a sound insulating material and a method for manufacturing the same.

[Conventional technology]

BACKGROUND ART Sheet-shaped sound insulating materials used for sound insulating purposes are conventionally known. This sound insulation sheet is made by mixing rubber, synthetic resin, filler, and various additives as necessary.
The mixture is kneaded and formed into a sheet using a known processing machine.
It is formed into a required shape by cutting, die-cutting, three-dimensional molding, etc., and is widely used in industries such as transportation machinery, industrial plants, and architecture for the purpose of sound insulation.

[Problem to be solved by the invention]

By the way, sheet-shaped sound insulating materials have a certain degree of soundproofing performance even when used alone, but for example, when applying soundproofing measures to a dash panel that separates the engine room and passenger compartment of a car, it is not possible to take soundproofing measures with only sheet-like sound insulating materials. However, in addition to sheet-like sound insulating materials, bulky felts made of defibrated fibers such as synthetic fibers and natural fibers impregnated with phenolic resin, glass fibers, and various synthetic foam materials have sound absorbing properties. They are molded and laminated, processed into any shape, and used as soundproofing materials. In this case, the sheet sound insulating material is usually supplied initially in the form of a roll or rectangular sheet of an appropriate size, and if it is molded to match the shape of the automobile dash panel in the example above, it will definitely become unnecessary. Trim residue will be generated. In addition, sheet-like sound insulating materials have a certain degree of rigidity, so when trying to mold them into a shape with large irregularities, a sufficient shape cannot be obtained with one heat and pressure molding. Before laminating with felt or the like, it is necessary to process the sheet-like sound insulating material alone by means such as heat forming or vacuum forming. If you plan to laminate with bulky felt without such pre-processing, just before placing the sheet-like sound insulating material in the mold, preheat it with a heat panel etc. to make it easy to form. There is a need. Also,
If you want to take soundproofing measures by partially attaching a sheet-like sound insulating material to bulky felt, or if you want to laminate the two after molding them separately, a step of bonding them with a suitable adhesive is necessary.

-We took soundproofing materials for dash panels as an example, but current sheet-like soundproofing materials can be used not only in automobiles but also when laminated with soundabsorbing materials and molded into the required shape to create soundproofing materials. have an issue.

That is the current situation.

[Means to solve the problem]

In view of the current situation, the present inventors have conducted extensive research and have succeeded in developing a soundproofing material using a coating agent and a method for producing the same.

Therefore, the gist of the present invention is as follows: 1. In a soundproofing material consisting of two layers, a soundproofing layer and a soundabsorbing layer, (
1) The sound insulation layer is made of thermoplastic resin or a mixture of thermoplastic resin and filler.1) cg/n? (2) The sound-absorbing layer is a breathable sound-absorbing material appropriately selected from bulky felt, synthetic resin foam material, and glass fiber, and the sound-insulating layer is a dry coating film formed by applying the above and drying it. A soundproofing material using a coating agent, characterized in that it is formed by coating and drying on at least one surface.

2. Apply thermoplastic resin or a mixture of thermoplastic resin and filler to the mold, place unformed or molded bulky felt on top of it, and close the mold. A method for producing a soundproofing material using a coating agent, which is characterized by pressure molding using a coating agent.

3. Apply thermoplastic resin or a mixture of thermoplastic resin and filler to the mold, close the mold, and inject the reaction liquid for polyurethane foam.

A method for producing soundproofing material using a coating agent, which involves heating.

exists in

When applying a thermoplastic resin to be applied as a sound insulating layer, it is heated to a coating temperature using a coating machine such as an applicator and then applied, but it solidifies as soon as it cools to room temperature. However, when heated, it is thermally reactivated and has adhesive properties again.

Thermoplastic resins that can be used include ethyl cellulose,
Vinyl acetate resin and its derivatives, polyethylene, ethylene-vinyl acetate copolymer, butyl methacrylic resin, polystyrene and copolymer, polyisobutylene, petroleum resin,
Examples include bituminous materials such as asphalt, polypropylene, polyamide resin, and polyester resin.

If the thermoplastic resin itself has a sufficiently high specific gravity, it is possible to form a sound insulation layer with the thermoplastic resin alone, but if the sound insulation performance is insufficient, various fillers may be used in combination as necessary. It is also possible to supplement sound insulation performance. Fillers that can be used include conventionally known powder fillers such as calcium carbonate, barium sulfate, clay, talc, and mica, as well as zinc white, zinc powder, lead powder, and iron powder to enhance performance as a sound insulation material. , copper powder, bronze powder,
It is preferable to include various metal powders such as aluminum powder, and when using conventionally known powder fillers, it is preferable to select pigments with relatively high specific gravity such as barium sulfate.

Below, a method for manufacturing a soundproofing material according to the present invention will be explained.

Apply thermoplastic resin to a mold for cold press using a conventional coating method such as an applicator at a rate of 1 to 10 kg/r.
rr Paint. If it is less than 1 kg/rrr, the desired sound insulation effect cannot be obtained, and if it exceeds 10 kg/rrr, the sound insulation effect will not improve in proportion to the amount of application, which is disadvantageous in terms of increased weight and cost. When a filler is used in combination, a suitably selected filler is uniformly dispersed after the thermoplastic resin is applied, and the thermoplastic resin is applied again to form a sound insulating layer. At this time, it may be applied to the entire surface of the mold, or it may be applied only to necessary areas.

Furthermore, pre-shaped bulky felt or unshaped bulky felt is stacked on top of the thermoplastic resin coated surface, the upper mold is lowered, and pressure molded at an appropriate pressure for an appropriate time. do. The pressing force and time are determined by the presence or absence of pre-processing to give the bulky felt shape, the thickness of the bulky felt, the degree of compression, productivity, etc., but while the applied thermoplastic resin has adhesive ability, Laminated molding of the sound absorbing layer is an essential condition.

When polyurethane foam is used for the sound absorbing layer, the molding foam is coated with thermoplastic resin and the filler is evenly distributed. Thereafter, a thermoplastic resin is applied again to form a sound insulating layer. When manufacturing by injection molding, a reaction solution for polyurethane foam is injected after the mold is closed. The reaction liquid is divided into two liquids, an isocyanate and a polyol, and the polyol further contains a foam stabilizer, a blowing agent, a catalyst, a coloring agent, and the like.

After injection, heating necessary for molding the foam material is carried out, but at this time it is essential that the thermoplastic resin be thermally reactivated and laminated and bonded to the sound absorbing layer.

[Effect]

The thermoplastic resin coated on the mold is adhesively laminated to a sound-absorbing layer such as bulky felt or polyurethane foam material along with the filler sprinkled in between to form a sound-insulating layer, realizing excellent sound-insulating performance as a whole.

〔Example〕

Examples are given below to provide a more detailed understanding of the present invention.

Naturally, the present invention is not limited to the following examples.

Example 1 Ethylene vinyl acetate copolymer resin was applied at an average weight of 0.5 kg/m using an applicator, and barium sulfate (
A mixed filler consisting of 30 parts by weight (manufactured by Sakai Chemical Industry Co., Ltd.) and 5 parts by weight of lead powder (manufactured by Kikuchi Shiki Kogyo Co., Ltd.) was mixed at an average weight of 0.5 kg/rr.
Then, ethylene vinyl acetate copolymer resin was applied again at an average rate of 0.5 kg/rrr. A bulky felt containing phenolic resin with a thickness of 30 cm was stacked on the coated surface, the upper mold was lowered, and a pressure of 3 kg/al was applied.
Pressure molding was performed for 0 seconds. An automobile dash silencer 1 was obtained in which a sound insulating layer made of ethylene vinyl acetate copolymer resin was laminated on one side of a felt sound absorbing layer.

Example 2 A total average of 1.5 kg of ethylene vinyl acetate copolymer resin/filler/ethylene vinyl acetate copolymer resin with the same composition as in Example 1 was applied to the entire lower mold surface of a mold for injection molding of polyurethane foam. m2 was applied and the mold was closed. After that, TDI/MDI from the inlet.
30 parts by weight of mixed isocyanate (manufactured by Sanyo Chemical Industries, Ltd.) and 100 parts by weight of polyether polyol (manufactured by Sanyo Chemical Industries, Ltd.)
120' C
15 minutes of heating was added. An automobile dash silencer 2 was obtained in which a sound insulating layer made of ethylene vinyl acetate copolymer resin was laminated on one side of a sound absorbing layer made of polyurethane foam material.

Comparative Example 1 Styrene-butadiene rubber, recycled rubber, synthetic resin, and filler were mixed and dispersed and processed into a sheet shape with a conventional thickness of 3.
The rubber sound insulating sheet of (3) was molded for an automobile dash part using a vacuum forming machine, and this was placed on the lower mold of a molding die in the same manner as in Example 1. Place the felt in layers and lower the upper mold, weighing 3 kg.
Heat and pressure molding was performed for 90 seconds at a pressure of /aJ. An automobile dash silencer 3 was obtained in which a rubber sound insulating layer was laminated on one side of a felt sound absorbing layer.

Comparative Example 2 Styrene-butadiene rubber, recycled rubber, synthetic resin, and filler were mixed and dispersed and processed into a sheet shape with a conventional thickness of 3.
A rubber-based sound insulating sheet of Kaku was molded for an automobile dash part using a vacuum forming machine, and this was placed on the lower mold of a urethane molding mold in the same manner as in Example 2. The mold was closed and TDI/MDI was injected from the injection port. 30 parts by weight of mixed isocyanate (manufactured by Sanyo Chemical Industries, Ltd.), 100 parts by weight of polyether polyol (manufactured by Sanyo Chemical Industries, Ltd.), 0 parts by weight of foam stabilizer (silicon oil)
．． 5 parts by weight, blowing agent (water) 0.5 parts by weight, reaction catalyst 0.
A polyol component consisting of 5 parts by weight and 2 parts by weight of a colorant was injected and heated at 120° C. for 15 minutes. An automobile dash silencer 4 was obtained in which a sound insulating layer made of a rubber sound insulating sheet was laminated on one side of a sound absorbing layer made of a polyurethane foam material.

Test method Each silencer was installed on the dash of a small passenger car.
Engine noise was measured using a microphone attached to the ear position of the passenger inside the vehicle.

Next, the engine sound was measured in the same manner with the silencer removed and no sound insulation measures taken, and the sound insulation performance was evaluated from the difference in the noise level when the silencer was not installed and when the silencer was installed.

(Margins below this page) Results Table 1 (Units in the table are dB) [Effects of the invention] The soundproofing material using the coating agent of the present invention has the same or higher performance than the soundproofing material using the conventionally known soundproofing sheet. Moreover, according to the method of manufacturing the sound insulation material according to the present invention, the trim scum of the sound insulation sheet that is generated in the conventional method is not generated, which helps to save resources and improves the sound insulation sheet molding process when manufacturing the sound insulation material. Alternatively, the preheating process for molding can be omitted; the process of laminating the sound insulation layer is the application of the coating material, so automation with a painting robot is possible; and the sound insulation coating material is a thermoplastic resin, so it can be cooled at the same time after application. Since it forms a coating film, it does not require heating for drying, so it can be applied to cold press, and by partially applying thermoplastic resin, it is possible to take intensive and rational sound insulation measures. The present invention provides a method for producing a soundproofing material that has excellent advantages.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a part of the soundproofing material manufactured according to claim 2. 1 is a sound insulation layer made of thermoplastic resin, and 2 is a sound absorption layer made of bulky felt. FIG. 2 is a sectional view of a part of the soundproofing material manufactured according to claim 3. 1 is a sound insulation layer made of thermoplastic resin, and 2' is a sound absorption layer made of polyurethane foam material.

Claims (1)

[Claims] 1. A soundproofing material consisting of two layers, a soundproofing layer and a soundabsorbing layer, (1) The soundproofing layer is made of thermoplastic resin or a mixture of thermoplastic resin and filler at 1 kg/m^2. (2) The sound absorbing layer consists of bulky felt, synthetic resin foam material,
1. A soundproof material using a coating agent, which is a breathable sound-absorbing material suitably selected from glass fibers, and is formed by coating and drying a sound-insulating layer on at least one surface of the sound-absorbing layer. 2. Apply thermoplastic resin or a mixture of thermoplastic resin and filler to the mold, place unformed or molded bulky felt on top of it, and close the mold. A method for producing a soundproofing material using a coating agent, which is characterized by pressure molding using a coating agent. 3. Applying a thermoplastic resin or a mixture of a thermoplastic resin and a filler to the mold, closing the mold, injecting a reaction liquid for polyurethane foam, and heating. A method of manufacturing soundproofing materials using a coating agent.