Soundproofing material manufacturing nozzle and method for manufacturing soundproofing material using the nozzle

Abstract

To provide a mouthpiece for manufacturing soundproofing materials and a method for manufacturing soundproofing materials using the mouthpiece, which can very simply vent gas generated during cross-linking foaming after extrusion molding of soundproofing materials with multiple hollow part.SOLUTION: A mouthpiece for manufacturing soundproofing materials used in extrusion molding of soundproofing materials 50 made of rubber sponge includes: an outer shape 201 consisting of an annular part with a rectangular cross-sectional shape of the mouthpiece 200; a horizontal stripe part 202 extending in a horizontal direction so as to vertically divide the rectangular annular part 201 into two or more parts; and a vertical stripe part 203 extending vertically so as to divide the rectangular annular part 201 into two or more parts on a left and right sides. A plurality of separating parts 300 for degassing are formed in the rectangular annular part 201.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a die for extruding soundproofing materials to be attached to, for example, automobile doors, and a method for manufacturing soundproofing materials using the die. [Background technology]

[0002] For example, when extruding a rubber sponge with a hollow portion, such as a weather strip attached around the door of a car, foaming gas is generated in the hollow portion during the heating process (foaming vulcanization process) that is carried out after the unvulcanized rubber is extruded from the extruder, and unless a gas vent hole is provided in the hollow portion, the shape of the hollow portion becomes unstable.

[0003] For this reason, a method has been disclosed in which a needle-like part is rotated relative to a hollow part after extrusion molding to make a hole and discharge the gas (see Patent Document 1). This allows holes to be drilled reliably and easily while avoiding interference from drilling obstacles such as weatherstrip mounting portions.

[0004] However, when using a die 400 such as that shown in Fig. 5 to extrude a soundproofing material 10 having a plurality of hollow portions 18 as shown in Fig. 6, it is necessary to provide a device for drilling holes for each of the hollow portions 18. In other words, it becomes necessary to drill holes in a total of eight places, four from the top and four from the bottom.

[0005] This soundproofing material 10 is attached to, for example, an automobile door, and has flat upper and lower surfaces 11 and 12, with two or more hollow sections 18 formed above and below by horizontal partition walls 15 extending laterally from left to right, and two or more hollow sections 18 formed on the left and right by vertical partition walls 16 extending vertically. Here, one horizontal partition wall 15 and three vertical partition walls 16 (16A, 16B, 16C) form two hollow sections 18 above and below and four hollow sections 18 on the left and right, for a total of eight hollow sections 18. The nozzle 400 is composed of a main body 201, a passage 202 for the passage of the extrusion material, and a core 203 for forming the hollow portion. The passage 202 has an outer shape consisting of a so-called rectangular ring-shaped portion 204, in which a strip-shaped portion of a certain width is formed into a continuous rectangular shape, a horizontal reinforcing portion 205 extending horizontally so as to divide the rectangular ring-shaped portion 204 into two equal parts, one above the other, and a vertical reinforcing portion 206 (here, three vertical reinforcing portions 206A, 206B, 206C) extending vertically so as to divide the rectangular ring-shaped portion 204 into four equal parts, one left and one right.

[0006] Other examples disclosed include forming grooves in the trim of a weatherstrip to allow gas to escape, and then filling the grooves in a filling process after the vulcanization process (see Patent Document 2), and similarly forming small holes in the trim to allow gas to escape into the atmosphere, and then sealing it with a coating of thermoplastic elastomer or resin (Patent Document 3).However, these do not take into consideration gas venting in a soundproofing material 10 having multiple hollow portions 18 formed therein, as shown in Figure 6. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2019-14024 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-184624 [Patent Document 3] Patent No. 3579835 Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, the object of the present invention is to provide a nozzle for manufacturing soundproofing material that can very easily release gas generated during cross-linking foaming after extrusion molding of a soundproofing material having multiple hollow portions formed therein, and a method for manufacturing soundproofing material using the same. [Means for solving the problem]

[0009] In order to achieve the above object, the die for manufacturing a soundproof material of the present invention is a die for manufacturing a soundproof material used in an extrusion molding process of a soundproof material (50) made of a rubber sponge having a plurality of hollow portions (58) formed therein, The die (200) comprises a main body (201), a passage (202) through which the extrusion material passes, and a core (203) for forming the hollow portion (58), The passage portion (202) is composed of an outer shape (204) formed of a rectangular ring-shaped portion, horizontal reinforcing portions (205) extending laterally to the left and right so as to divide the rectangular ring-shaped portion (204) into two or more portions vertically, and vertical reinforcing portions (206) extending vertically so as to divide the rectangular ring-shaped portion (204) into two or more portions horizontally, On the outlet side of the rectangular annular portion It is characterized by the formation of a plurality of separation parts (300).

[0010] Furthermore, a method for manufacturing a soundproof material using the die for manufacturing soundproof material of the present invention is a method for manufacturing a soundproof material using the die for manufacturing soundproof material (200) according to claim 1, in which the soundproof material (50) is made of rubber sponge having a rectangular cross-sectional outer shape and having two or more hollow portions (58) formed above and below by horizontal partition walls (55) extending laterally to the left and right and two or more hollow portions (58) formed on the left and right by vertical partition walls (56) extending vertically, The width (300L) of the separation portion (300) is set so that the separation portion (59) formed corresponding to the separation portion (300) is closed by utilizing the expansion that occurs when the soundproofing material (50) after extrusion molding is foamed in a heating process.

[0011] It should be noted that symbols in parentheses indicate corresponding elements or matters described in the drawings and in the detailed description to be described later. [Effects of the Invention]

[0012] According to the present invention, the die used in the extrusion molding process for a soundproofing material made of rubber sponge with multiple hollow portions formed therein has separation portions corresponding to each hollow portion, so that gaps corresponding to the width of the separation portions are formed on the outer surface of the soundproofing material immediately after it is extruded from the die. These gaps are sealed and connected in the subsequent heating process (crosslinking foaming process) by utilizing expansion caused by foaming when the material passes through, for example, a microwave heating device (UHF). Gas generated in the hollow portions is released from the gaps that exist between immediately after extrusion and when they are sealed in the heating process. Furthermore, by setting the width of the separation section so that the gap formed corresponding to the separation section is closed by utilizing the expansion that occurs when foaming occurs in the heating process, a hollow section without gaps is reliably formed in the soundproofing material. This eliminates the problem of the hollow portion having an unstable shape. Furthermore, there is no need for a device for drilling holes in the hollow portion, and the structure is simple because it is only necessary to form a separation portion in the nozzle.

[0013] The soundproofing material thus produced is entirely cross-linked and foamed by extrusion molding, and therefore has excellent hydrophobicity and can be used in places where it is exposed to water. In addition, a thin elastic layer called the "skin layer" is formed on the outside of the cross section, which is denser than the foam layer.This layer does not allow water to pass through to the inside, but sound can enter the inside due to the vibration of the elastic thin film.As sound waves enter, energy is attenuated inside, allowing for effective sound absorption.

[0014] Furthermore, according to the present invention, the vertical reinforcing portions are arranged so as to divide the rectangular annular portion equally into two or more portions on the left and right, and the separation portions are formed at positions above and below the rectangular annular portion where they intersect with lines that bisect the core portion, respectively, so that a hollow portion having equal left and right lengths in the cross-sectional shape is formed. Furthermore, the horizontal reinforcement portions are arranged so as to divide the rectangular ring-shaped portion into two or more equal portions, vertically, so that hollow portions having equal vertical heights are formed in the cross-sectional shape.

[0015] Furthermore, according to the present invention, the soundproofing material is made of rubber sponge with a specific gravity of 0.2 or less, so that the hollow portion acts as an air layer, and the sound absorption peak of the soundproofing material can be shifted to a low frequency of approximately 800 Hz to 1000 Hz. Furthermore, the sound absorption peak can be easily fine-tuned by changing the position of the horizontal and vertical partition walls to change the size of the hollow space. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is an exterior side view of an automobile. [Figure 2] 2 is an enlarged cross-sectional view taken along line AA in FIG. 1, showing a state in which a soundproofing material 50 according to an embodiment of the present invention has been attached. [Figure 3] 1A and 1B are diagrams showing a nozzle 200 for extruding soundproofing material 50 according to an embodiment of the present invention, in which (a) shows the discharge side of the nozzle 200 (the outlet side of the extruded material), and (b) shows the extruder side of the nozzle 200 (the inlet side of the extruded material). [Figure 4] FIG. 1 is an enlarged perspective view showing a soundproofing material 50 according to an embodiment of the present invention, in which (a) is a soundproofing material 50 in which gaps have been filled by foaming, and (b) is a soundproofing material 50 in which gaps have been formed immediately after extrusion molding. [Figure 5] FIG. 1 is a diagram showing the discharge side (extrusion material outlet side) of a die 400 for extrusion molding a soundproofing material 10 according to a conventional example. [Figure 6] FIG. 1 is an enlarged perspective view showing a soundproofing material 10 according to a conventional example. DETAILED DESCRIPTION OF THE INVENTION

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A soundproofing material manufacturing die and a soundproofing material manufacturing method using the die will be described with reference to the drawings. As shown in FIGS. 1 and 2, this soundproofing material 50 is applied to a sheet main body 31 of a door hole seal 30 attached to a door 100 of an automobile.

[0018] The door hole seal 30 is provided between a door inner panel 102 and a door trim 103 that constitute a door 100 together with a door outer panel 101, and covers an opening H formed in the door inner panel 102. The door hole seal 30 is made of a sheet body 31 with excellent sound insulation and sound absorption properties, and a synthetic resin film (PE film) 32 that is integrated with the sheet body 31 by heat welding (welding portion T) and that attaches the sheet body 31 to the inside of the door inner panel 102. A butyl rubber sealant 33 is provided on the outer surface of the synthetic resin film 32 as an adhesive, and this bonds the door hole seal 30 to the door inner panel 102.

[0019] The seat main body 31 may be integrated with a resin molded product instead of the synthetic resin film (PE film) 32, or may be integrated with the door inner panel 102. As for the means of integration, for example, if the integrated product is a resin molded product, a hook-shaped locking portion may be provided on the resin molded product to lock the seat main body 31, or if the integrated product is the door inner panel 102, a fixing means such as a clip, double-sided tape, adhesive, or hot melt may be attached to the seat main body 31 in advance, and the seat main body 31 may be attached to the door inner panel 102 with the fixing means. Also, as shown in FIG. 1 , the seat main body 31 is attached to the vehicle exterior surface of the synthetic resin film (PE film) 32 here, but it can also be attached to the vehicle interior surface. When the seat body 31 is attached to the door 100, its upper and lower ends are open.

[0020] The soundproofing material 50 applied to the seat main body 31 is strip-shaped and made entirely of EPDM sponge. In the extrusion molding process, it is extruded using an extruder (not shown) with a nozzle 200 as shown in Figure 3, and in the subsequent heating process (vulcanization and foaming process), it is vulcanized and foamed by passing it through a microwave heating device (UHF) (not shown). In this embodiment, EPDM is used as the raw rubber for the rubber sponge that makes up the soundproofing material 50 from the viewpoints of sound-damping properties, productivity, durability, etc., but other rubbers may be used as long as they form a skin layer when cross-linked and foamed by extrusion molding. Examples include NR (natural rubber), NBR (nitrile rubber), Q (silicone rubber), SBR (styrene rubber), and CR (chloroprene rubber).

[0021] As shown in Figure 4(a), soundproofing material 50 is strip-shaped and includes upper surface 51, lower surface 52, left side surface 53, and right side surface 54, and its cross-sectional outer shape is rectangular. Inside, two or more hollow sections 58 are formed above and below by horizontal partition walls 55 extending laterally from left to right, and two or more hollow sections 58 are formed on the left and right by vertical partition walls 56 extending vertically. Here, one horizontal partition wall 55 and three vertical partition walls 56 (56A, 56B, 56C) form two hollow sections 58 above and below and four hollow sections 58 on the left and right, for a total of eight hollow sections 58. Furthermore, four protrusions 51a and four protrusions 52a are formed on the upper surface 51 and the lower surface 52, respectively.

[0022] The soundproofing material 50 has one of its substantially flat upper surface 51 and lower surface 52 fixed to a synthetic resin film (PE film) 32, and several pieces extending up and down are arranged side by side in the left-right direction (from the front to the rear of the door 100) to form the sheet main body 31. Adjacent soundproofing materials 50 are simply butted together, but they may also be fixed with an adhesive or the like. Furthermore, when the sheet main body 31 is attached to the door inner panel 102 using a fixing means such as a clip without using the synthetic resin film (PE film) 32, one of the upper surface 51 and lower surface 52 of the soundproofing material 50 is attached to the door inner panel 102. Furthermore, since the protrusions 51a, 52a formed on the upper surface 51 and the lower surface 52 are small, the upper surface 51 and the lower surface 52 are approximately flat, and when either one of the surfaces is attached to the synthetic resin film (PE film) 32 or the door inner panel 102, that one surface is made flat due to elastic deformation. Furthermore, although not shown, the seat main body 31 has holes and cutouts formed on the sides for passing various cables through and for workers to insert their hands into when working.

[0023] 3(a) and 3(b), the die 200 comprises a main body 201, a passage 202 through which the extrusion material passes, a core 203 for forming the hollow portion 58, and a core connecting portion 203a that connects the core to the main body, and the core connecting portion 203a is formed only on the extruder side (the inlet side for the extrusion material) as shown in FIG. 3(b) so as not to affect the cross-sectional shape after extrusion. The passage 202 has an outer shape that is a so-called rectangular ring-shaped portion 204, in which a strip-shaped portion of a certain width is formed into a rounded rectangle without any interruption, a horizontal reinforcing portion 205 that extends horizontally to divide the rectangular ring-shaped portion 204 into equal two parts, top and bottom, and a vertical reinforcing portion 206 (here, three vertical reinforcing portions 206A, 206B, 206C) that extends vertically to divide the rectangular ring-shaped portion 204 into equal four parts, left and right. A rounded rectangle is a rectangle with rounded corners, and is treated here as one variation of a rectangle. A plurality of separation sections 300 are formed in the passage section 202. Here, eight separation sections 300 in total are formed in the core section 203, one for each, corresponding to the hollow sections 58 formed in the soundproofing material 50.

[0024] More specifically, as shown in FIG. 3, the separation portions 300 are formed at positions (eight positions in total) that intersect with lines CL that bisect the core portions 203 formed at the top and bottom of the inside of the rectangular annular portion 201.

[0025] It is sufficient that the separation section 300 is formed at least on the discharge side of the passage section (the outlet side of the extruded material), but from the viewpoint of durability, it is preferable that it is formed over the entire range from the extruder side of the passage section (the inlet side of the extruded material) to the discharge side (the outlet side of the extruded material).

[0026] As a result, immediately after being extruded from the nozzle 200, the soundproofing material 50 passes through the separation portion 300 formed in the nozzle 200, and as a result, a separation portion 59 of a distance corresponding to the width 300L of the separation portion 300 is formed on the upper surface 51 and the lower surface 52 of the soundproofing material 50, as shown in Figure 4(b), and this separation portion 59 is designed to be closed and connected by utilizing expansion during foaming in a heating process using a microwave heating device (UHF) provided after the extrusion process of the soundproofing material 50. Note that when the soundproofing material 50 is closed and connected, pressure is applied outward by the foaming gas generated in the hollow portion 58, and therefore in the soundproofing material 50 after the heating process, this connected position becomes the above-mentioned convex portions 51a, 52a. In this case, the width 300L of the separation portion 300 is set so that the separation portion 59 formed corresponding to the width 300L of the separation portion 300 is reliably closed by utilizing the expansion during foaming. For example, if the EPDM sponge has a specific gravity of 0.2 to 0.3, the width 300L of the separation portion 300 is preferably set to 0.3 mm or less, and if the EPDM sponge has a specific gravity of 0.1 to 0.2, the width 300L of the separation portion 300 is preferably set to 0.5 mm or less.

[0027] The rubber composition used as the extrusion molding material at this time contains at least EPDM sponge, a crosslinking agent, a foaming agent, and carbon black (CB) as a reinforcing material.

[0028] Examples of non-conjugated dienes in ethylene-α-olefin copolymers (EPDM; ethylene-α-olefin-non-conjugated diene copolymers) include 1,4-hexadiene, dicyclopentadiene, and 5-ethylidene-2-norbornene, and examples of α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene.

[0029] Examples of crosslinking agents include sulfur and peroxides, and sulfur is used in the present invention.

[0030] Examples of the foaming agent include azo compounds, nitroso compounds, hydrazine derivatives, sodium bicarbonate compounds, and microcapsules. Physical foaming may be performed without using a foaming agent, or both may be used in combination.

[0031] Other examples of the additives include inorganic fillers, softeners, vulcanization accelerators, etc., which can be appropriately selected and used. Examples of inorganic fillers include calcium carbonate, etc.; examples of softeners include liquid polybutene, mineral oil, liquid polyisobutylene, liquid polyacrylic ester, etc.; and examples of vulcanization accelerators include thiazoles and thiurams.

[0032] According to the method for manufacturing soundproofing material 50 using soundproofing material manufacturing die 200 configured as described above, separation portions 300 corresponding to each hollow portion 58 are formed in soundproofing material manufacturing die 200 used in the extrusion molding process of soundproofing material 50 made of rubber sponge having multiple hollow portions 58 formed therein. Therefore, separated portions 59 corresponding to width 300L of separation portions 300 are formed on the upper and lower surfaces of soundproofing material 50 immediately after it is extruded from die 200. These separated portions 59 are closed and connected by utilizing expansion due to foaming when it passes through a microwave heating device (UHF) thereafter. Gas generated in each hollow portion 58 is released from separated portions 59, which exist from immediately after it is extruded until it is closed and connected during the heating process. This eliminates the problem of the hollow portion 58 having an unstable shape. Furthermore, no device for drilling holes in the hollow portion 58 is required, and the structure is simple because it is only necessary to form the separation portion 300 in the mouthpiece 200.

[0033] The soundproofing material 50 thus manufactured is entirely cross-linked and foamed by extrusion molding, and therefore has excellent hydrophobicity and can be used in places where it is exposed to water. In addition, a thin elastic layer called the "skin layer" is formed on the outside of the cross section, which is denser than the foam layer.This layer does not allow water to pass through to the inside, but sound can enter the inside due to the vibration of the elastic thin film.As sound waves enter, energy is attenuated inside, allowing for effective sound absorption.

[0034] In the case of the soundproofing material 50 made of rubber sponge with a specific gravity of 0.2 or less, the hollow portion 58 will be deformed so as to be crushed. This is because, when heating with hot air only, local cross-linking foaming progresses first on the outside where the hot air hits, hardens, and then the inside cross-linking foaming occurs, resulting in a mismatch in the timing of the cross-linking foaming between the outside and inside.When manufacturing a rubber sponge such as soundproofing material 50, whose outer shape is a continuous rectangular strip of a certain width with multiple hollow sections 58 formed inside, this mismatch in timing has a significant impact on the quality of the shape, and hollow structures with low specific gravity, such as those with a specific gravity of 0.2 or less, will generate heat unevenly and will not be able to form a hollow structure according to the designed shape.

[0035] In this case, by adding a small amount (2.0 phr) of highly heat-generating carbon nanotubes (CNTs) to the extrusion molding material, collapse of the hollow portion 58 can be prevented and the molded product can be manufactured in the shape as designed. Here, the amount of carbon nanotubes added is set to 2.0 phr, but is not particularly limited. To improve microwave heat generation, more than 2.0 phr can be added, but from an economical standpoint, a small amount is preferable. Therefore, the amount of carbon nanotubes added is preferably 3.0 phr or less, more preferably 2.5 phr or less, and even more preferably 2.0 phr or less and 0.5 phr or more.

[0036] Carbon nanotubes have excellent electrical and thermal conductivity and are sometimes used as composite materials with rubber. However, in the case of extrusion molding a soundproofing material 50, as in this embodiment, whose cross-sectional outer shape is a rounded rectangle and whose interior has two or more hollow sections 58 formed above and below by horizontal partition walls 55 extending laterally to the left and right, and two or more hollow sections 58 formed above and below by vertical partition walls 56 extending vertically, and in which carbon nanotubes are added to the rubber composition that is the extrusion molding material, the extrusion molding material provides high heat generation by microwaves and a low specific gravity after foaming, and the hollow shape of the soundproofing material 50 made of rubber sponge whose specific gravity after cross-linking foaming is 0.2 or less is stabilized and the upper and lower surfaces 51, 52 are flat, has not previously existed, and there are no prior art documents that describe such an idea.

[0037] The carbon nanotubes that can be used include single-walled carbon nanotubes and multi-walled carbon nanotubes, and the shape of the aggregates is not particularly limited, and may be particulate (fluffy) or bundled.

[0038] In particular, soundproofing material 50 made of rubber sponge with a specific gravity of 0.2 or less has multiple hollow sections 58 formed by partitions made of horizontal partition walls 55 and vertical partition walls 56, and hollow sections 58 are air layers, so the sound absorption peak can be shifted to a low frequency of approximately 800 Hz to 1000 Hz. Furthermore, by changing the positions of the horizontal partition walls 55 and the vertical partition walls 56 and changing the size of the hollow portion 58, the sound absorption peak can be easily fine-tuned.

[0039] If the soundproofing material 50 shown in Figure 4(a) has a total of eight hollow sections 58 formed in two rows vertically and four columns horizontally, then a nozzle 200 such as that shown in Figure 3(a) is used. However, if the soundproofing material 50 has a total of six hollow sections 58 formed in two rows vertically and three columns horizontally, then a nozzle that forms six corresponding hollow sections 58 should be used. Furthermore, in the soundproofing material 50, the hollow portions 58 are formed in two rows vertically by the horizontal partition walls 55, but it is also possible to use two horizontal partition walls 55 and form three rows vertically and three columns horizontally, for a total of nine hollow portions 58, by using mouthpieces of corresponding shapes. Furthermore, as long as the requirements of the present invention are met, the number of horizontal partition walls 55, the number of rows and columns of the hollow portions 58 vertically or horizontally, and the shape of the hollow portions 58 can be changed, and various forms are included in the present invention, and these can also be manufactured according to the designed shape by using mouthpieces that correspond to the cross-sectional shape of the soundproofing material.

[0040] Furthermore, the structure of the soundproofing material 50 according to an embodiment of the invention has been described as being applied to the sheet main body 31 of the door hole seal 30 attached to the door 100 of an automobile, but it can also be installed in places other than the door 100 of an automobile, for example, as a part in the engine compartment or inside a tire. Furthermore, the soundproofing material according to the embodiment of the invention can be used in various places other than automobiles, such as doors of trains, ships, and airplanes, and floors and walls of houses.

[0041] In addition, by closing both ends by additional processing such as molding to seal the inside, it can also be used as a heat insulating material. [Explanation of symbols]

[0042] 10 Soundproofing materials 11 Top side 12 Bottom side 13 Left side 14 Right side 15 Horizontal partition wall 16(16A, 16B, 16C) Vertical partition wall 18 Hollow part 30 Door Hole Seal 31 Seat body (soundproofing material) 32 PE film (synthetic resin film) 33 Butyl rubber sealant 50(50A, 50B) Soundproofing material 51 Top side 51a Convex part 52 Bottom surface 52a Convex part 53 Left side 54 Right side 55 Horizontal Partition Wall 56(56A, 56B, 56C) Vertical partition wall 58 Hollow part 59 Separation part 60 Soundproofing material 61 Soundproofing material 100 doors 101 Door outer panel 102 Door inner panel 103 Door trim 200 cap 201 Main body 202 Passage section 203 Core part 203a Core connection part 204 Rectangular Annular Section 205 Horizontal reinforcement 206(206A, 206B, 206C) Vertical reinforcement 300 Separation section 300L Separation width 400 nozzle CL Bisecting line H opening T welded part

Claims

1. A die for manufacturing a soundproofing material used in an extrusion molding process for a soundproofing material made of a rubber sponge having a plurality of hollow portions formed therein, the die comprises a main body, a passage for the extrusion material to pass through, and a core for forming the hollow portion; The passage portion has an outer shape formed of a rectangular annular portion, horizontal reinforcing portions extending in the left-right direction so as to divide the rectangular annular portion into two or more portions vertically, and vertical reinforcing portions extending in the vertical direction so as to divide the rectangular annular portion into two or more portions horizontally, A nozzle for manufacturing soundproofing material, characterized in that a plurality of separation sections are formed on the discharge side of the rectangular annular section.

2. A method for producing a soundproofing material, using the die for producing a soundproofing material according to claim 1, wherein the soundproofing material is made of a rubber sponge having a rectangular cross-sectional outer shape and having two or more hollow portions formed above and below by horizontal partition walls extending laterally to the left and right and two or more hollow portions formed on the left and right by vertical partition walls extending vertically, A method for manufacturing soundproofing material using a nozzle for manufacturing soundproofing material, characterized in that the width of the separation portion is set so that the gap formed corresponding to the separation portion is closed by utilizing the expansion that occurs when the soundproofing material after extrusion molding is foamed in a heating process.

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