JPH04271972A - Soundproof material for pillar - Google Patents

Abstract

PURPOSE:To develop a soundproof material for a pillar part which possesses the superior safety and workability, and the soundproof effect because of the perfect charge inside the pillar. CONSTITUTION:A molded urethane foam which is shaped according to the shape of a pillar is compressed to 1/2-1/50 in volume ratio and a soundproof material for pillar part is formed by enclosing the molded urethane foam in the compression state with a film having a melting point of 80-200 deg.C.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soundproofing material for pillars of automobiles.

0002

[Prior Art] In order to improve the quietness of the interior of a passenger car, a portion of the interior of the pillar was partially removed to prevent engine noise and wind noise from transmitting through the interior of the pillar and entering the interior of the vehicle. Filling has been carried out. For example, a two-component urethane injection device is installed on the automobile assembly line, and the urethane foam solution is injected through the injection hole in the pillar section, and the foam is foamed and filled by the heat generated when passing through an automobile paint heating and drying oven. It has been taken.

[0003] Another method has also been proposed in which a low-temperature vulcanization type highly foaming sealer is inserted into the interior of the pillar portion, and the sealer is similarly foamed and filled using the heat of a heating drying oven. (Unexamined Japanese Patent Publication No. 62-62882, etc.).

Another method has also been proposed in which a slab urethane foam with slow dimensional recovery is compressed and inserted into the interior of a pillar portion or the like before dimensional recovery, and the interior is filled using the dimensional recovery of the foam material. (Japanese Patent Application Laid-Open No. 62-139739, etc.).

However, these conventional techniques have the following drawbacks. In other words, in urethane injection on the line side, there are operational safety issues as hazardous substances such as isocyanates are handled, and two-component urethane injection equipment is large and expensive, requiring maintenance and labor costs. . In addition, heat-foaming type sealers are easily affected by heating temperature and temperature rise rate, and there is a risk that the foaming rate may change if the line speed of the automobile assembly line changes, making it unreliable for filling the interior. . Furthermore, with the method of inserting slab urethane foam into the pillar, which has a slow dimensional recovery, the shape will recover after about 1 minute, no matter how slow the dimensional recovery is. In addition to the time-consuming process of compressing the urethane foam, there is a natural limit to the compression rate when compressing by hand, so if the opening is small, it will not improve work efficiency much.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to develop a soundproofing material for a pillar portion that is safe to work with, has good work efficiency, and is highly reliable for internal filling.

[0007]

[Means for Solving the Problems] In order to solve the above problems, the present inventors have conducted intensive research and found that a molded urethane foam material molded according to the shape of the pillar has a volume ratio of 1/2 to 1/50. This led to the development of a soundproofing material for pillars in which a foam material is wrapped in a compressed film with a melting point of 80°C to 200°C. The foam material, which is sufficiently compressed during work, makes it easier to insert the foam material into the specified location, which was previously extremely difficult. The film surrounding it melts, and the compressed foam material recovers its shape and fills the predetermined portion of the pillar without any gaps.

[0008] If the volume compression ratio is less than 1/2, the improvement in working efficiency will not be sufficient, and if the opening is small, there is a risk that the working will be difficult. Furthermore, if the volume compression ratio exceeds 1/50, there is a possibility that the foam material will not recover 100% to its original shape even if the film melts, and in that case, the desired soundproofing effect cannot be achieved.

[0009] The urethane foam is not particularly limited as long as it has heat resistance exceeding 200°C and shape recovery from a volume compression ratio of 1/50. If the foam material has a heat resistance of 200° C. or lower, there is a risk that the foam material will be melted and damaged during shape recovery, making it impossible to fill the inside of the pillar. The same applies when there is no shape recovery property from a volumetric compression ratio of 1/50. The melting point of the film is 80℃~200℃
It is mandatory that If the melting point is less than 80° C., there is a risk that the film will soften during high-temperature storage or transportation in the summer, and the foam material will not be able to resist the shape recovery properties of the foam material and expand before being worked. If the temperature exceeds 200° C., the film will not melt, the foam material will not be able to recover its shape, and will not fill the pillar portion, and there is a possibility that the desired soundproofing effect will not be obtained. When the foam material is wrapped in a film during compression, it is preferable to create a so-called vacuum pack state in which no air is allowed inside.

0010

[Example] In order to provide an understanding of the present invention, examples are described below. Needless to say, the present invention is not limited to the following examples.

[0011]

[Example 1] A molded urethane foam material formed into a pillar shape was compressed to 1/12 in terms of volume, and simultaneously wrapped in a vacuum state with an EVA (ethylene-vinyl acetate copolymer) resin film with a melting point of 80°C. , Soundproofing material 1 was obtained.

0012

[Example 2] A molded urethane foam material formed into a pillar shape was compressed to 1/12 in terms of volume ratio, and simultaneously wrapped in a vacuum state with a vinyl chloride resin film having a melting point of 200°C to obtain a soundproofing material 2.

[0013]

[Comparative Example 1] A molded urethane foam material formed into a pillar shape was compressed to 1/12 in terms of volume ratio, and simultaneously wrapped in a vacuum state with a polyamide resin film having a melting point of 220° C. to obtain a soundproofing material 3.

[0014]

[Comparative Example 2] A molded urethane foam material formed into a pillar shape was compressed by 3/4 in terms of volume ratio, and simultaneously wrapped in a vacuum state with a polyamide resin film having a melting point of 220° C. to obtain a soundproofing material 3.

[0015]

[Test method] Soundproofing materials 1 to 4 were inserted into the opening of a front quarter pillar-shaped part of a car.
Heating was carried out at ℃ for 20 minutes. The pillar parts after heating were observed from the vertical part and the state of filling was evaluated.

[0016]

[Results] Soundproofing material 1 and soundproofing material 2 maintained the compressed state of the foam material well, and the workability was excellent as the soundproofing material could be inserted easily and in a short time from the opening. The film surrounding the soundproofing material completely melted, and the shape of the soundproofing material was completely restored, filling the inside of the front quarter pillar without any gaps. On the other hand, the film of the soundproofing material 3 did not dissolve completely;
The filling was not sufficient. The film of the soundproofing material 4 was not completely dissolved, and it was somewhat difficult to insert the soundproofing material 4 through the opening.

[0017]

[Effects of the Invention] The soundproofing material of the present invention does not require any equipment on the automobile assembly line, is safe because it uses a foam material after reaction, and can be easily inserted into narrow openings where it is difficult to work. In addition, by melting the film using the heat of the paint drying oven, the compressed urethane foam material recovers its shape and fills the pillar without any gaps, reducing engine noise and wind noise inside the pillar. to prevent it from entering the vehicle interior.

Claims (1)

[Claims] [Claim 1] Front quarter pillar of an automobile;
For soundproofing materials for pillars to fill the inside of center pillars, rear quarter pillars, etc., molded urethane foam molded to the shape of the pillar is compressed by 1/2 to 1/50 in volume ratio, and the mold in the compressed state is A soundproofing material for pillars, characterized in that urethane foam is wrapped in a film having a melting point of 80°C to 200°C.