JPH04345834A - Manufacture of soundproof material - Google Patents

Abstract

PURPOSE:To manufacture efficiently a soundproof material of good sound insulation in fewer manufacturing processes and at low manufacturing cost by applying directly a sound-insulated layer forming material to a sound absorbing material composed of a porous material and curing the forming material to form a sound-insulated layer integrally with the sound absorbing material. CONSTITUTION:A soundproof material suitable for an enclosure of industrial equipment, an automobile, building and the like is provided with a sound absorbing material formed by a porous material using a fiber aggregate composed of fibers such as a foamed body of soft urethane foam or the like, rough wool felt, polyester fiber, polypropylene fiber and glass fiber. A sound insulation layer forming material composed of a urethane elastomer composition, a polyvinyl chloride resin composition, an alkyd resin composition and the like is applied directly to the sound absorbing material to cure the sound absorbing material. As above-mentioned, the manufacturing method consists of the sound absorbing material (porous body) forming process, the trimming process of sound absorbing material and the coating process of sound insulation layer forming material, and the sound insulation material of good sound insulation performance can be manufactured in fewer manufacturing processes.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a method for producing a sound insulating material having a sound absorbing layer and a sound insulating layer, which is suitably used for enclosures of industrial equipment, automobiles, buildings, etc. The present invention relates to a method for manufacturing a soundproofing material, which can produce a soundproofing material that is cost-effective and has good soundproofing performance.

0002

[Prior Art] Conventionally, soundproofing materials used in applications that require excellent soundproofing performance, such as panels separating the engine room and interior of automobiles and enclosures for industrial equipment, have been made of foams such as soft urethane foam, coarse wool, etc. A sound absorbing layer made of a porous material such as an aggregate of felt or other fibrous materials is mixed with a polyvinyl chloride or rubber material and a large amount of filler, and then formed into a sheet by extrusion or calendering. Soundproofing materials that are integrated with molded soundproofing layers are known, and examples of such soundproofing materials include dash insulators and floor insulators, which are known as soundproofing materials for automobiles.

A soundproofing material having such a soundproofing layer is shown in FIG.
As shown in , the sound insulating layer and the sound absorbing layer are molded separately,
It is manufactured by bonding these together using an adhesive or adhesive. In this case, the sound insulating layer is prepared in the form of a long roll or a sheet cut to a certain size, and when a three-dimensional shape is to be formed, this sheet is formed by compression molding, vacuum forming, or the like. On the other hand, in addition to being used in the form of a slab (flat plate), the sound absorbing layer is generally used as a porous material having a three-dimensional shape by compression molding, injection molding, blow molding, or the like.

0004

[Problems to be Solved by the Invention] However, as shown in FIG. 3, the above-mentioned sound insulation material requires a lot of effort in the production of the sound insulation layer and the sound absorption layer before the sound insulation layer and the sound absorption layer are laminated and integrated. It takes time and effort. In other words, there are several steps before the bonding process, such as forming and trimming each layer.In particular, the sound insulation layer starts from a sheet-shaped molded product, so it goes through four steps: cutting, preheating, forming, and trimming the sheet. It is very time-consuming to form. In addition, these steps are difficult to automate, and a large amount of loss occurs during trimming, which is very disadvantageous from the standpoint of product cost and resource conservation.

[0005] Furthermore, the above-mentioned soundproofing materials may not be able to provide sufficiently satisfactory soundproofing performance. That is,
A gap may occur between the sound insulation layer and the sound absorption layer due to misalignment of the bonding between the sound insulation layer and the sound absorption layer or uneven adhesive strength on the bonding surface, and such molding defects may cause problems during installation. There is a risk of sound leaking from the opening or the outer periphery.

The present invention has been made in view of the above-mentioned circumstances, and provides a method for producing soundproofing materials that can efficiently and stably produce soundproofing materials with good soundproofing performance through fewer manufacturing steps and at low manufacturing costs. The purpose is to provide

[0007]

[Means and Effects for Solving the Problems] In order to achieve the above object, the present inventor has made extensive studies and found that a urethane elastomer composition, polyvinyl chloride, etc. A sound insulation layer is formed by directly applying a sound insulation layer forming material made of a resin composition, an alkyd resin composition, etc. by a spray coating method, a roll coating method, etc., and curing it to form a sound insulation layer on the above sound absorption material. It is possible to omit the sheet cutting process, preheating forming process, trimming process, and bonding process of the sound absorbing layer and the sound insulating layer to form the sound absorbing material (porous material) as shown in Figure 1. It is possible to obtain a sound insulating material in which the sound absorbing layer and the sound insulating layer are integrally laminated through the three steps of the process, the trimming process of the sound absorbing material, and the process of applying the sound insulating layer forming agent, and the sound absorbing layer and the sound insulating layer are laminated well. It has been found that an integrated soundproofing material having excellent soundproofing performance can be obtained.

[0008] To explain this point in more detail, in the conventional manufacturing method, as shown in FIG. After that, it is laminated with a porous material supplied as a sound absorption layer, but as mentioned above, the sound insulation layer forming material is applied directly to the porous material and cured to form the sound insulation layer. As a result, as shown in FIG. 1, the large-scale and expensive sheet cutting process, preheat forming process, and trimming process can be omitted, and the manufacturing process can be greatly simplified. In addition, the amount of debris generated by trimming is significantly reduced, and the process of bonding the sound absorbing layer and the sound insulating layer and the drying process can also be omitted.
There is no need for adhesives or pressure-sensitive adhesives, which reduces the need for raw materials, equipment,
It is possible to rationalize many aspects such as waste and labor. Furthermore, regarding the sound insulation performance of the obtained sound insulation material, the adhesion, shape following, and adhesion between the porous material surface and the sound insulation layer have been significantly improved, and the conventional problems such as misalignment of the bonded surface and peeling of the bonded surface have been improved. It has been found that sound insulation performance can be effectively improved as there are no gaps at all, sound leakage from the openings and the outer periphery is greatly reduced, and installation accuracy is also improved. .

Therefore, in the present invention, a sound-insulating layer forming material is directly applied to a sound-absorbing material made of a porous material, and the sound-insulating layer is integrally formed on the sound-absorbing material by curing the forming material. The present invention provides a method for manufacturing a soundproofing material, characterized in that a soundproofing material is obtained by integrally laminating a soundproofing material and a soundproofing layer.

[0010] To explain the present invention in more detail below, the method for producing a soundproofing material of the present invention involves forming a soundabsorbing material to serve as a soundabsorbing layer using a porous material, and directly applying a soundproofing layer forming material to the soundabsorbing material. By curing this, a sound insulating layer is formed.In this case, the porous material forming the sound absorbing layer is one that has been conventionally used as the sound absorbing layer of sound insulating materials. Specific examples thereof include foams such as flexible urethane foam, coarse felt, and fiber aggregates made of fibers such as polyester fibers, polyester composite fibers, polypropylene fibers, polypropylene composite fibers, and glass fibers.

[0011] Further, as the sound insulation layer forming material for forming the sound insulation layer, any material can be used as long as it can form a hardened layer having sound insulation properties. In consideration of efficiency, fast-curing materials are desirable, and specifically, urethane elastomer compositions, polyvinyl chloride resin compositions, and alkyd resin compositions are preferably used. More specifically, a fast-curing urethane elastomer composition can be obtained by, for example, reacting a polyisocyanate component partially containing a prepolymer having an isocyanate group at the end with components such as a polyol, a chain extender, and a catalyst. (Unexamined Japanese Patent Publication No. 63-10
7775) can be suitably used, and as the polyvinyl chloride resin composition and alkyd resin composition, polyvinyl chloride paste-based compositions and alkyd resins already known as materials for undercoating of automobiles can be used. system compositions can be suitably used. In addition, various fillers can be added to these compositions as necessary. Specifically, fillers include talc, clay,
Examples include calcium carbonate, barium sulfate, mica, mica, and silica sand, and inorganic or organic fibrous fillers may also be added.

As the material for forming the sound insulation layer, a fast-curing material is preferably used as described above, but in this case, the curing speed may affect the uniformity of the sound insulation layer. When forming layers, the effect becomes greater. For example, if the curing speed is too fast, unevenness tends to occur on the surface of the porous material, which not only deteriorates the appearance but also causes discontinuous points in the coating film, which may reduce the sound insulation properties. On the other hand, if the curing speed is too slow, the applied sound-insulating layer-forming material may penetrate to a high degree into the porous material, or sag may occur in areas with steep slopes. In order to reliably prevent such inconvenience from occurring, the curing speed of the fast-curing sound insulating layer forming material is not particularly limited, but the tack-free time should be 180 seconds or less, particularly about 10 to 60 seconds. It is preferable that

[0013] The present invention provides the porous material with a desired shape,
For example, forming the porous material into a sheet, slab, or three-dimensional shape, and applying the sound insulation layer forming material directly to the surface of the porous material,
This is cured to form a sound insulation layer on the porous material. In this case, the method of directly applying the sound insulation layer forming material to the surface of the porous material is by spraying using a spray gun or the like. Various methods can be used, such as a roll coating method using a roll coater, a coating method using a spatula or a brush, etc., but a spray coating method is particularly recommended for porous materials with three-dimensional shapes. It is preferable. In this case, in order to reliably obtain a uniform coating film, it is preferable to optimize the curing speed of the sound insulation layer forming material as described above, but the type of spray gun, discharge amount, distance from the coating surface, etc.
The angle also affects the uniformity of the coating film, and it is important to adjust these appropriately. In addition, after performing the spray application method,
The coated surface can also be compressed using a mold with the same shape as the product. Further, although not particularly limited, it is preferable to trim the periphery and openings of the porous material before applying the sound insulating layer forming material.

According to such a direct coating method, the amount of coating can be changed locally, and the thickness of the sound insulating layer can be increased only in areas where particularly high sound insulating properties are required. Furthermore, it is also possible to partially change the type and color tone of the coating film components, allowing for more detailed quality design.

[0015]

EXAMPLES The present invention will be specifically explained below with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[Example 1] A porous molded body (fiber aggregate) with an apparent average density of 0.06 g/cm3 consisting of polyester fibers of 6 to 8 deniers and an average length of 40 mm bonded with low melting point polyester fibers was made of gold. It was obtained by hot air molding using a mold, and the outer periphery and openings of this molded body were trimmed. The weight after trimming was 1.0 kg.

On the other hand, 852.5 parts of MDI (parts by weight, the same applies hereinafter), 365.3 parts of carbodiimidated MDI, propylene oxide added to propylene glycol, and then capped with ethylene oxide with a hydroxyl value of 56.
571.7 parts of polyoxyalkylene diol and 10.5 parts of dipropylene glycol were reacted at 80° C. for 3 hours to obtain a compound serving as the main ingredient of the sound insulation layer forming material. Also,
74.5 parts of polyoxyalkylene diol, 19.0 parts of ethylene glycol, 2.0 parts of lead naphthenate (catalyst),
A curing agent was prepared by mixing 0.5 part of Irganox 1010 (stabilizer).

This base agent and curing agent were sprayed onto the surface of the porous molded body using a high-pressure sprayer at a volumetric flow rate ratio of 1/1 to form a coating film with an average thickness of 2.7 mm and a film density of 0.98 g/cm3. (
A sound insulating material with a total weight of 4.4 kg was produced by forming a sound insulating layer).

When the sound insulation layer of the obtained sound insulation material was observed, it was found that there were no pinholes in appearance and there was no air permeability. Furthermore, we conducted a 180° peel test between the sound insulation layer and the porous molded body (sound absorption layer) to test the adhesion between both layers, which ultimately resulted in material failure, confirming the excellent adhesion between both layers. .

[Comparative Example] An extruded polyvinyl chloride sheet (density 1.7 g/cm3, thickness 1.5 mm) was cut, preheated, molded, and trimmed to form a porous sheet similar to that used in Example 1. A soundproof material having a total weight of 4.4 kg was produced by pasting the molded body (fiber aggregate) using a urethane adhesive.

[0021] When this soundproofing material was subjected to the same peeling test as in Example 1, the soundproofing layer and the soundabsorbing layer peeled off at 0.7 kg/cm2.

[Example 2] Polyester fiber with crimp number of 15.0 crimp/inch (6 denier, cut length 38 mm)
10 parts per 100 parts of low melting point polyester composite yarn (
A yarn with a structure in which a polyester core is covered with a low melting point polyester sheath, 4 denier, cut length 51 mm, number of crimps 8 per inch, sheath side melting point 95 ° C) and 15 parts of polyethylene-polypropylene composite yarn (polypropylene composite yarn) A yarn with a core covered with a polyethylene sheath, 2 denier, cut length 51 mm, number of crimp 10 threads/inch, sheath side melting point 130°C) is thoroughly mixed, and this is compressed at 110°C to form a board. It was molded into a primary molded body with dimensions (60 x 120 x 1.0 cm). The apparent density of this molded body is approximately 0.150
g/cm3. This molded body was set in a mold similar to that used in Example 1, heated with hot air at 140°C for 2 minutes, and then cooled to 80°C to obtain a porous molded body (fiber aggregate). . The volume of the obtained molded body increased to about 230%, and the apparent density became about 0.06 g/cm3. After trimming the outer periphery and openings of this molded body, the weight was measured, and the total weight was 1.0 kg.

A sound insulating layer was formed on the surface of this porous molded body (fiber aggregate) in the same manner as in Example 1, and the total weight was 4.4 kg.
g of soundproofing material was obtained.

[Example 3] First, asphalt obtained by stirring blown asphalt at 240°C for 72 hours,
Rubber asphalt was obtained by adding 1% by weight of SBR rubber latex with a solid content of 50%. This rubber asphalt and polyester resin are extruded using a general spinning nozzle so that the sheath side surface layer is rubber asphalt and the core layer is polyester resin, and then stretched and cooled to form rubber asphalt. and 2 with polyester
A 1-15 denier fiber with a heavy structure was obtained.

Next, the rubber asphalt and polyester composite yarn cut to a length of 51 mm was mixed at a ratio of 20% by weight to a polyester single fiber having a length of 6 denier, a length of 38 mm, and a crimp degree of 18. A molded product having an apparent density of 0.06 g/cm 3 was obtained by hot air molding using a mold similar to that used in Example 1. After trimming the outer periphery and openings of this molded body, the weight was measured, and the total weight was 1.0 kg.

A sound insulating layer was formed on the surface of this porous molded body (fiber aggregate) in the same manner as in Example 1, and the total weight was 4.4 kg.
g of soundproofing material was obtained.

The sound insulation performance of the sound insulation materials of Examples 1 to 3 and Comparative Example 1 was evaluated by the following method. Evaluation Method First, a test device was prepared by partitioning the sound source room and the sound receiving room with a steel panel on which soundproofing material was installed, and installing the soundproofing material on this panel. Then, a speaker is placed in the sound source room to generate sound using a noise generator, and an intensity microphone is placed in the sound receiving room to automatically measure the sound passing through the panel at 50 points, and calculate the average value. Transmitted power was calculated by multiplying by the front area of the panel.

On the other hand, the average sound pressure level on the sound source room side is measured while moving the microphone with a microphone rotator, and the above-mentioned transmitted power is subtracted from the average value of this sound pressure level to calculate the sound transmission loss (dB), Sound insulation performance was evaluated based on the loss value. The results are shown in Figure 2.

As is clear from the results shown in FIG. 2, the soundproofing materials of Examples 1 to 3 all have the same total weight as the soundproofing material of the comparative example, but have lower performance in the entire frequency range. It showed better sound insulation performance (Example 1 had an average of 5
dB improvement).

[0030]

According to the method for producing a soundproofing material of the present invention, a soundproofing material with good soundproofing performance can be efficiently and stably produced with a small number of manufacturing steps and at a low manufacturing cost.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram illustrating the manufacturing method of the present invention in the order of steps.

FIG. 2 is a graph showing the sound insulation performance of sound insulation materials of Examples 1 to 3 and a comparative example.

FIG. 3 is an explanatory diagram illustrating a conventional manufacturing method in the order of steps.

Claims (2)

[Claims] Claim 1: A sound-insulating layer forming material is directly applied to a sound-absorbing material made of a porous material, and the forming material is cured to integrally form a sound-insulating layer on the sound-absorbing material, thereby forming a sound-absorbing layer and a sound-insulating layer. A method for producing a soundproofing material, characterized in that a soundproofing material is obtained by integrally laminating the following. 2. The method for producing a sound insulation material according to claim 1, wherein a urethane elastomer composition, a polyvinyl chloride resin composition, or an alkyd resin composition is used as the sound insulation layer forming material.