Soundproofing cushioning material and method for manufacturing the same

Abstract

To provide a sound damping material superior in impact resistance and sound insulation and further superior in ice resistance and waterproofness.SOLUTION: The non-woven fabric surface including multiple entangled short fibers of a sound damping area 2 is exposed on the surface on the tire side and the opposite surface of a sound damping material 1, and the surface of a continuous resin area 3 is continuously exposed side by side and adjacent to the sound damping area. The sound damping area 2 is formed in this manner; therefore, there is no covering material on the top and back surfaces of the sound absorbing area 2, and sound absorbing performance of the sound absorbing area 2 is not reduced. Also, water absorbing performance is suppressed by the resin area 3, and thus ice resistance and waterproofness can be improved.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a soundproofing cushioning material that is attached to the inner surface of a tire house of a vehicle body and absorbs the impact caused by foreign objects such as pebbles that are kicked up while the vehicle is traveling and collide with the vehicle body, thereby suppressing impact noise and preventing damage to the vehicle body near the tires, and a method for manufacturing the soundproofing cushioning material. [Background technology]

[0002] For example, Patent Document 1 shows a soundproofing buffer material (fender liner) comprising a nonwoven fabric in which many short fibers are entangled with each other. In this way, soundproofing buffer material made of nonwoven fabric has excellent impact resistance and soundproofing properties (especially sound absorption properties) because the countless gaps formed between the entangled fibers absorb the impact caused by the collision of a foreign object.

[0003] However, the soundproofing cushioning material made only of nonwoven fabric made of short fibers as described above is prone to absorbing moisture because the gaps formed between the short fibers are exposed to the surface, resulting in a very large surface area. Therefore, in winter, the moisture absorbed in the nonwoven fabric freezes, and if the ice that forms on the surface of the nonwoven fabric grows in a direction approaching the tires, the ice may interfere with the tires and adversely affect the steering of the vehicle.

[0004] In contrast, the soundproofing buffer material shown in Patent Document 2 aims to improve water resistance and resistance to adhesion of foreign matter by covering the surface of the soundproofing buffer material made of nonwoven fabric with a water-resistant film. However, if the surface of the nonwoven fabric is completely covered with the water-resistant film in this way, the water-resistant film blocks air, and the sound absorbing effect of the nonwoven fabric cannot be fully exhibited.

[0005] In order to solve such problems, Patent Document 3 has an object to provide a soundproof cushioning material that has excellent impact resistance and soundproofing properties, as well as excellent icing resistance and waterproofing, and discloses a soundproof cushioning material to be attached to the inner surface of a wheel house of a vehicle body, the soundproof cushioning material comprising a base layer made of a nonwoven fabric in which a large number of short fibers are entangled with each other, and a resin surface layer covering the surface of the base layer, the resin surface layer having countless pores that communicate between the base layer and the outside air, having a basis weight in the range of 50 to 400 g / m2, and containing 60% or more of a molten resin component. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2000-264255 A [Patent Document 2] JP 2002-348767 A [Patent Document 3] JP 2008-132972 A Summary of the Invention [Problem to be solved by the invention]

[0007] The soundproof cushioning material disclosed in Patent Document 3 has insufficient sound absorption performance because it has a resin surface layer covering the surface of the nonwoven fabric. Specifically, even if the resin surface layer has countless holes that connect the base layer to the outside air, unlike air intake and sound absorption, sounds with wavelengths larger than the hole diameter are reflected by the resin surface layer and are not attenuated (absorbed) by the base layer made of nonwoven fabric with many short fibers entangled with each other, and in fact Patent Document 3 does not disclose any evaluation test results regarding sound absorption performance.

[0008] In view of the above problems associated with the prior art, the present invention has an object to provide a soundproof cushioning material that is excellent in impact resistance and soundproofing properties, as well as in ice resistance and waterproofing properties, and a method for manufacturing the soundproof cushioning material. [Means for solving the problem]

[0009] In other words, the soundproof cushioning material of the present invention is a soundproof cushioning material that is attached to the inner surface of a tire house of a vehicle body, and is characterized by having a soundproof cushioning region in which nonwoven fabric made of a large number of short fibers entangled with each other is arranged, and a continuous resin region that forms a continuous surface with the soundproof cushioning region via a boundary portion.

[0010] The soundproofing cushioning material of the present invention is a soundproofing cushioning material that is attached to the inner surface of a tire house of a vehicle body, and is characterized by having a soundproofing cushioning region in which a nonwoven fabric made of a large number of short fibers entangled with each other is arranged, and a rib resin region that is formed to protrude beyond the surface of the soundproofing cushioning region via the boundary portion with the soundproofing cushioning region.

[0011] Furthermore, the soundproofing cushioning material of the present invention is a soundproofing cushioning material that is attached to the inner surface of a tire house of a vehicle body, and is characterized by having a soundproofing cushioning region in which a nonwoven fabric made of a large number of short fibers entangled with each other is arranged, a continuous resin region that forms a continuous surface with the soundproofing cushioning region through its boundary, and a rib resin region that is formed to protrude above the surface of the soundproofing cushioning region through the boundary with the soundproofing cushioning region.

[0012] In addition, the manufacturing method of the soundproof cushioning material of the present invention is a soundproof cushioning material to be attached to the inner surface of the tire house of a vehicle body, the soundproof cushioning material having a soundproof cushioning region made of nonwoven fabric in which a large number of short fibers are entangled with each other, and a resin region that forms a continuous surface via a boundary portion with the soundproof cushioning region, and is characterized in that the nonwoven fabric is compressed to control the boundary of the interface portion on the nonwoven fabric side, and the density is increased to suppress the flow of resin and stabilize the boundary portion between the soundproof cushioning region and the continuous resin region.

[0013] Furthermore, the manufacturing method of the soundproofing cushioning material of the present invention is a soundproofing cushioning material to be attached to the inner surface of a tire house of a vehicle body, the soundproofing cushioning material having a soundproofing cushioning region made of nonwoven fabric in which a large number of short fibers are entangled with each other, and a rib resin region formed to protrude above the surface of the soundproofing cushioning region via a boundary portion with the soundproofing cushioning region, and is characterized in that the nonwoven fabric is compressed to control the boundary portion at the interface on the soundproofing cushioning region side, and the density is increased to suppress the flow of resin and stabilize the boundary portion between the soundproofing cushioning region and the rib resin region.

[0014] Furthermore, the manufacturing method of the soundproofing buffer material of the present invention is a soundproofing buffer material to be attached to the inner surface of the tire house of a vehicle body, the soundproofing buffer material having a soundproofing buffer region in which a nonwoven fabric made of a large number of short fibers entangled with each other is arranged, a continuous resin region that forms a continuous surface through the boundary with the soundproofing buffer region, and a rib resin region that is formed to protrude above the soundproofing buffer region surface through the boundary with the soundproofing buffer region, and is characterized in that the nonwoven fabric is compressed to control the boundary of the interface on the soundproofing buffer region side, and the density is increased to suppress the flow of resin and stabilize the boundary between the soundproofing buffer region and the continuous resin region and / or the rib resin region.

[0015] Thus, the soundproofing buffer material of the present invention has a soundproofing buffer region made of a nonwoven fabric having a large number of intertwined fibers, and therefore has excellent sound absorption and impact resistance. In addition, this soundproofing buffer material has a continuous resin region that forms a continuous surface with the soundproofing buffer region through the boundary and / or a rib resin region that is formed protruding from the soundproofing buffer region through the boundary, thereby improving water resistance, ice adhesion resistance, and waterproofing. In particular, the continuous resin region and the rib resin region are integrally formed, and not only does the rib resin region have a protruding portion from the continuous resin region, but the rib resin region is formed between two soundproofing buffer regions, so that sufficient synthesis is imparted to both the soundproofing buffer region and the continuous resin region that forms a continuous surface through the boundary. In particular, the formation of an intersection where one rib resin region intersects with another rib resin region eliminates anisotropy in rigidity, and rigidity is imparted to the entire soundproofing buffer material in all directions.

[0016] As a result of the boundary portion being a compressed nonwoven fabric region that is more compressed than the nonwoven fabric in the soundproof buffer region, impregnation of the nonwoven fabric in the soundproof buffer region with resin from the continuous resin region and / or the rib resin region during injection molding is prevented, and the sound absorption performance of the nonwoven fabric in the soundproof buffer region is maintained at a high level.

[0017] Specifically, the compressed nonwoven fabric region has a density three times or more that of the soundproof buffer region, so that impregnation of the nonwoven fabric of the soundproof buffer region with resin from the continuous resin region and / or the rib resin region during injection molding is sufficiently prevented. If the compressed nonwoven fabric region has a density less than three times that of the soundproof buffer region, impregnation of the nonwoven fabric of the soundproof buffer region with resin from the continuous resin region and / or the rib resin region during injection molding is not completely prevented, and sufficient sound absorption performance is not achieved. It is not industrially easy to make the compressed nonwoven fabric region have a density six times or more that of the soundproof buffer region, and more production costs than necessary will be incurred.

[0018] By providing an area where the nonwoven fabric of the soundproof buffer area extends on the resin area side of the boundary portion, it is possible to ensure sufficient unity, continuity, and bonding between the resin area and the soundproof buffer area. Effect of the Invention

[0019] As described above, the soundproof cushioning material of the present invention exhibits excellent effects such as excellent impact resistance and sound absorbing properties, as well as excellent ice resistance and waterproof properties. [Brief description of the drawings]

[0020] [Figure 1] FIG. 2 is a partial side view showing the periphery of a wheel house of a vehicle body. [Diagram 2] 1 is a perspective view of a soundproof cushioning material according to an embodiment of the present invention; [Diagram 3] 1 is a schematic partial cross-sectional view of a soundproof cushioning material according to an embodiment of the present invention. [Figure 4] 4 is another partial schematic cross-sectional view of the soundproof cushioning material according to the embodiment of the present invention. FIG. [Diagram 5] FIG. 2 is another perspective view of the soundproof cushioning material according to the embodiment of the present invention. [Figure 6] 4 is another partial schematic cross-sectional view of the soundproof cushioning material according to the embodiment of the present invention. FIG. [Figure 7] 4 is a schematic partial cross-sectional view of another soundproof cushioning material according to an embodiment of the present invention. FIG. [Figure 8] 1 is a photograph of a soundproof cushioning material according to an embodiment of the present invention. [Figure 9] 1 is a photograph of a soundproof cushioning material according to an embodiment of the present invention. [Figure 10] 1 is a photograph of a soundproof cushioning material according to an embodiment of the present invention. [Figure 11] 1 is a photograph of a soundproof cushioning material according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 shows a partial side view of the periphery of a tire 102 of an automobile fitted with a soundproofing cushioning material 1 according to an embodiment of the present invention. The soundproofing cushioning material 1 is shaped to fit an inner surface 101a of a tire house 101 of a vehicle body 100, and is fitted to the inner surface 101a.

[0022] 2 and 5 are schematic perspective views of a soundproofing buffer material 1. This soundproofing buffer material 1 is composed of a soundproofing buffer area 2, the upper surface of which is attached to a vehicle body, and a resin area 3, which is provided in parallel with and adjacent to the soundproofing buffer area 2 and is substantially continuous with it. The resin region 3 is formed by integrally injection molding the continuous resin region 3a shown in FIGS. 2 and 5 and the rib resin region 3b shown in FIG.

[0023] The soundproof buffering region 2 is provided in such a manner that the nonwoven fabric 4 having a large number of mutually entangled short fibers is held by the resin region 3 via the boundary portion 5 and laid in the region between the resin regions 3. As a result, the resin region 3 is provided substantially continuously in parallel with and adjacent to the soundproof buffering region 2, and is exposed substantially continuously together with the soundproof buffering region 2 in parallel with and adjacent to the soundproof buffering region 2 on the tire side surface of the soundproof buffering material 1. In addition, the surface of the nonwoven fabric 4 having a large number of mutually entangled short fibers of the soundproof buffering region 2 is exposed on the tire side surface and the opposite surface of the soundproof buffering material 1, and the surface of the continuous resin region 3a is exposed substantially continuously in parallel with and adjacent to the nonwoven fabric 4. As a result of the soundproof buffering region 2 being formed in this manner, there is nothing covering either the front or back surface of the soundproof buffering region 2, and the sound absorbing capacity of the soundproof buffering region 2 is not reduced by the covering.

[0024] The soundproofing buffer material 1 has excellent sound absorption and impact resistance due to the formation of countless minute voids inside the nonwoven fabric 4 that constitutes the soundproofing buffer area 2. In addition, this soundproofing buffer material 1 has a continuous resin area 3a that is substantially continuous with and adjacent to the soundproofing buffer area 2, which reduces the water absorption rate and increases water resistance, thereby improving icing resistance and waterproofing. In particular, if the resin area 3 is formed from a hydrophobic resin material, the water resistance can be further improved.

[0025] The rib resin region 3b is formed to protrude beyond the surface of the soundproof buffer region 2 via a boundary portion 5 with the soundproof buffer region 2. This rib resin region 3b is formed integrally with the continuous resin region 3a by injection molding. The rib resin region 3b is also formed between two soundproof buffer regions 2. Furthermore, an intersection portion 6 is formed where one rib resin region 3b intersects with another rib resin region 3b.

[0026] The boundary portion 5 is a compressed nonwoven fabric region 4a which is more compressed than the nonwoven fabric 4 of the soundproof buffer region 2, which is made of a nonwoven fabric 4 having a large number of mutually entangled short fibers. The compressed nonwoven fabric region 4a has a density which is 3 to 6 times that of the soundproof buffer region 2. An extension region 7 is defined on the resin region 3 side of the boundary portion 5, from which the nonwoven fabric 4 of the soundproof buffer region 2 extends.

[0027] Next, a method for manufacturing the soundproof cushioning material 1 according to one embodiment of the present invention will be described. First, a band-shaped pressing surface 9a, which is the top surface of the boundary forming protrusion 9 for forming the boundary 5, is formed in the mold 8. The distance between this pressing surface 9a and the opposing surface in the mold 8 is set to be about 60 to 80% of the plate thickness of the resin obtained by injection molding. The position of the pressing surface 9a set in the mold 8 is set inside the outer edge 2a of the soundproof buffer region 2 to an extent that it is possible to set the extension region 7 in the resin region 3 from which the nonwoven fabric 4 of the soundproof buffer region 2 extends.

[0028] Furthermore, the mold 8 is provided with a rib resin forming region 8a for forming the rib resin region 3b. This rib resin forming region 8a is arranged so that the rib resin region 3b is formed between the two soundproof buffer regions 2. Furthermore, as a result of the rib resin forming regions 8a being formed vertically and horizontally, a rib resin forming region intersection 8b is formed where one rib resin forming region 8a intersects with another rib resin forming region 8a.

[0029] A nonwoven fabric 4 having a large number of mutually entangled short fibers is placed in the above-described mold 8. The arrangement is such that, with the mold 8 set in a predetermined position before the resin is injected, the nonwoven fabric 4 covers a belt-shaped pressing surface 9a, which is the top surface of a boundary-forming protrusion 9 for forming the boundary 5, and the outer edge of the nonwoven fabric 4 extends outside the pressing surface 9a, thereby making it possible to set an extension region 7 in the resin region 3 from which the nonwoven fabric 4 of the soundproof buffer region 2 extends.

[0030] In this state, resin is injected into the mold 8 to obtain the soundproofing buffer material 1 according to the embodiment of the present invention. That is, the resin injected into the mold 8 is stopped by the boundary portion 5 formed by the band-shaped pressing surface 9a and does not permeate into the soundproofing buffer area 2, forming the continuous resin area 3a and the ribbed resin area 3b, and preventing a decrease in the sound absorption capacity of the soundproofing buffer area 2 due to the resin permeation. Since the extension area 7 from which the nonwoven fabric 4 of the soundproofing buffer area 2 extends is set in the resin area 3, the continuity between the soundproofing buffer area 2, the continuous resin area 3a, and the ribbed resin area 3b is maintained, and a soundproofing buffer material 1 with integrity can be obtained. EXAMPLES

[0031] In order to confirm the usefulness of the present invention, photographs of a soundproof cushioning material 1 according to the present invention, i.e., a soundproof cushioning material 1 (Example) having a soundproof cushioning region 2 made of nonwoven fabric 4, a continuous resin region 3a forming a continuous surface via a boundary portion 5, and a ribbed resin region 3b, are shown in Figures 8 to 11. [Explanation of symbols]

[0032] Reference Signs List 1...Soundproof cushioning material, 3...Resin region, 2...Soundproof cushioning region, 4...Nonwoven fabric, 7...Extension region, 3b...Rib resin region, 5...Boundary portion, 9a...Pressing surface, 8...Mold.

Claims

1. A soundproofing cushioning material is attached to the inner surface of a tire house of a vehicle body, the soundproofing cushioning material comprising a soundproofing cushioning region in which nonwoven fabric made of a large number of short fibers entangled with each other is disposed, and a continuous resin region which forms a continuous surface with the soundproofing cushioning region via a boundary portion, the soundproofing cushioning material being characterized in that the soundproofing cushioning region is exposed on the tire-side surface together with the continuous resin region in parallel with and adjacent to the continuous resin region and is substantially continuous therewith, the nonwoven fabric surface of the soundproofing cushioning region is also exposed on the surface opposite to the tire-side surface of the soundproofing cushioning material, the continuous resin region surface is exposed in parallel with and adjacent to the continuous resin region and is substantially continuous therewith, and a joining region is set where the nonwoven fabric of the soundproofing cushioning region extends on the resin region side of the boundary portion.

2. A soundproofing cushioning material to be attached to the inner surface of a tire house of a vehicle body, the soundproofing cushioning material comprising a soundproofing cushioning region in which a nonwoven fabric made of a large number of short fibers entangled with each other is disposed, and a rib resin region formed to protrude above the surface of the soundproofing cushioning region via a boundary portion between the soundproofing cushioning region and the soundproofing cushioning region, the soundproofing cushioning region being exposed substantially continuously together with the continuous resin region on the surface facing the tire, the nonwoven fabric surface of the soundproofing cushioning region being exposed on the surface opposite to the tire side surface of the soundproofing cushioning material, the continuous resin region surface being exposed substantially continuously together with the continuous resin region on the surface facing the tire, and a joining region being set where the nonwoven fabric of the soundproofing cushioning region extends toward the resin region side of the boundary portion.

3. a soundproofing buffer material to be attached to the inner surface of a tire house of a vehicle body, the soundproofing buffer material comprising: a soundproofing buffer region in which a nonwoven fabric made of a large number of short fibers entangled with each other is disposed; a continuous resin region which forms a continuous surface with the soundproofing buffer region through a boundary portion; and a rib resin region which is formed to protrude above the surface of the soundproofing buffer region through the boundary portion with the soundproofing buffer region, the soundproofing buffer material being characterized in that the soundproofing buffer region is exposed substantially continuously together with the continuous resin region on the surface facing the tire, the nonwoven fabric surface of the soundproofing buffer region is exposed on the surface opposite to the tire side surface of the soundproofing buffer material, and a joining region is set in which the surface of the continuous resin region is exposed substantially continuously alongside and adjacent to the continuous resin region, and the nonwoven fabric of the soundproofing buffer region extends toward the resin region side of the boundary portion.

4. A method for manufacturing a soundproof cushioning material to be attached to the inner surface of a tire house of a vehicle body, the soundproof cushioning material having a soundproof cushioning region made of a nonwoven fabric in which a large number of short fibers are entangled with each other, and a resin region that forms a continuous surface via a boundary portion with the soundproof cushioning region, the method for manufacturing a soundproof cushioning material comprising compressing the nonwoven fabric to suppress the boundary portion at the nonwoven fabric side, increasing the density to suppress the flow of resin and stabilizing the boundary portion between the soundproof cushioning region and the continuous resin region, a band-shaped pressing surface that compresses the nonwoven fabric to 60 to 80% of the plate thickness of the resin is set in a mold at the boundary portion, and the position of the pressing surface set in the mold is set so that the soundproof cushioning region is pressed against the resin region. a nonwoven fabric having a large number of entangled short fibers is set in the mold in a predetermined position before resin is injected, the nonwoven fabric covers a band-shaped pressing surface which is a top surface of a boundary-forming convex portion for forming a boundary, the outer edge of the nonwoven fabric extends outward from the pressing surface, and the resin is disposed in such a manner that a bonding area can be set in the resin area where the nonwoven fabric of the soundproof buffering region extends, and resin is injected into the mold in this state to form a bonding area in the resin area where the nonwoven fabric of the soundproof buffering region extends.

5. A method for manufacturing a soundproof cushioning material to be attached to the inner surface of a tire house of a vehicle body, the soundproof cushioning material comprising a soundproof cushioning region made of a nonwoven fabric in which a large number of short fibers are entangled with each other, and a ribbed resin region formed to protrude beyond the soundproof cushioning region surface via a boundary portion between the soundproof cushioning region and the ribbed resin region, the method for manufacturing a soundproof cushioning material comprising compressing the nonwoven fabric to suppress the boundary portion at the soundproof cushioning region side, increasing the density to suppress the flow of resin and stabilizing the boundary portion between the soundproof cushioning region and the ribbed resin region, a band-shaped pressing surface that compresses the nonwoven fabric to 60 to 80% of the plate thickness of the resin is set in a mold at the boundary portion, and the position of the pressing surface set in the mold is set to a position that is closer to the resin region than the boundary portion. a nonwoven fabric having a large number of entangled short fibers is set in the mold in a predetermined position before resin is injected, the nonwoven fabric covers a band-shaped pressing surface which is the top surface of a boundary forming convex portion for forming a boundary, the outer edge of the nonwoven fabric extends outward from the pressing surface, and the nonwoven fabric is arranged in such a manner that a bonding area where the nonwoven fabric of the soundproof buffering region extends can be set in the resin area, and resin is injected into the mold in this state to form a bonding area where the nonwoven fabric of the soundproof buffering region extends in the resin area.

6. A method for manufacturing a soundproofing buffer material to be attached to the inner surface of a tire house of a vehicle body, the soundproofing buffer material comprising a soundproofing buffer region in which a nonwoven fabric made of a large number of short fibers entangled with each other is arranged, a continuous resin region which forms a continuous surface with the soundproofing buffer region through a boundary portion, and a rib resin region which is formed to protrude beyond the soundproofing buffer region surface through the boundary portion with the soundproofing buffer region, the method comprising compressing the nonwoven fabric to suppress the boundary portion at the soundproofing buffer region side, increasing the density and suppressing the flow of resin, thereby stabilizing the boundary portion between the soundproofing buffer region and the continuous resin region and / or the rib resin region, and setting a band-shaped pressing surface in a mold for compressing the nonwoven fabric to 60 to 80% of the plate thickness of the resin at the boundary portion, and pressing the nonwoven fabric against the mold. a nonwoven fabric having a large number of entangled short fibers is set in the mold in a predetermined position before resin is injected, the nonwoven fabric covers the band-shaped pressing surface which is the top surface of the boundary forming convex portion for forming the boundary, the outer edge of the nonwoven fabric extends outside the pressing surface, and the nonwoven fabric is arranged in such a manner that a bonding area where the nonwoven fabric of the soundproof buffering region extends can be set in the resin region, and resin is injected into the mold in this state to form a bonding area where the nonwoven fabric of the soundproof buffering region extends in the resin region.

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