Polyurethane molded body and sound-absorbing material

Abstract

Provided are a polyurethane molded body and a sound-absorbing material having a sound-absorbing effect. A polyurethane molded body (1) is provided with segments (2) made of polyurethane, joining sections (3) at which a plurality of adjacent segments are joined to each other, and communication holes (4), and is characterized in that the segments (2) are molded in a state in which at least a portion thereof is curved and at least a portion thereof has an end portion (5) separated from the adjacent segments (2). A polyurethane molded body (1a) according to a first embodiment is a molded body in which a polyurethane sheet segment passes through a sieve having a mesh of 2 mm in advance. In contrast, the polyurethane molded body (1b) according to the second embodiment is a molded body that does not pass through a sieve having a 2 mm mesh in advance.

Description

Technical Field

[0001] The present invention relates to a polyurethane molded body having sound absorbing properties and a sound absorbing material. Background Art

[0002] In the past, polyurethane molded products used as sound-absorbing materials and / or heat-insulating materials for use in buildings and the like have been proposed. For example, according to the description of Patent Document 1, the following porous plate is proposed. The porous plate is made of crushed hard polyurethane foam and bonded by an adhesive; the hard polyurethane foam has a density of 30 to 200 kg / m 3 , preferably 50 to 130 kg / m 3 The present invention has a bulk density of at least 2 mm, preferably at least 5 mm, particularly preferably an average particle size of 5 to 20 mm and a binder content of 3 to 25% by weight, preferably 5 to 12% by weight.

[0003] Thus, there are described the porous plates used in a wide range of applications, such as as a support in a package or as a heat insulating partition between a refrigerating compartment and a freezing compartment in a refrigerator.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent document 1: Japanese Patent Laid-Open No. 8-258160 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, in the prior art example shown in Patent Document 1, there are the following problems. According to Patent Document 1, the rigid polyurethane foam used is crushed, and it is particularly preferred to have an average particle size of 5 to 20 mm and an adhesive content of 3 to 25% by weight, preferably 5 to 12% by weight. The average particle size of the crushed rigid polyurethane foam is the size specified above, so it is assumed that a large proportion of the unit structure is maintained without being destroyed. Since the unit structure of the rigid polyurethane foam forms independent bubbles, each unit is an independent structure. In this case, it is assumed that a large proportion of the units are not connected to adjacent units. As a result, the sound absorption effect is limited to a certain range, and there is a problem that the sound absorption effect cannot be fully exerted.

[0009] The present invention is intended to solve the conventional problems, and an object of the present invention is to provide a polyurethane molded body and a sound absorbing material having a sound absorbing effect.

[0010] Means for solving problems

[0011] The first embodiment of the polyurethane molded body of the present invention comprises polyurethane segments, connecting portions where a plurality of adjacent segments are connected to each other, and communicating holes, wherein the segments are molded in a state where at least a portion is in a tortuous state and at least a portion has an end separated from the adjacent segments.

[0012] Thus, the polyurethane molded body has segments, connecting parts and communicating holes, and thus has air permeability. Furthermore, the segments are connected to each other at the connecting parts, at least a part is in a zigzag state, and at least a part has an end separated from an adjacent segment. Therefore, the vibration of sound of the polyurethane molded body is attenuated, and a sound absorbing effect is achieved.

[0013] In addition, the polyurethane molded body may be a molded body in which the segments are previously passed through a sieve with a mesh size of 2 mm. In this case, the segments made of polyurethane are previously passed through a sieve with a mesh size of 2 mm, so that the density after compression molding is high, and the segments, the joints, and the communicating holes are formed more uniformly. Therefore, a stable sound absorbing effect is achieved.

[0014] In addition, the polyurethane molded body may be a molded body in which the segments have not been previously passed through a sieve with a mesh size of 2 mm. In this case, the polyurethane segments have not previously been passed through a sieve with a mesh size of 2 mm, so that the density after compression molding is low, and weight reduction can be achieved. In addition, the sound absorption effect can be further improved.

[0015] The sound absorbing material of the second aspect of the present invention includes the polyurethane molded article. Thus, since the polyurethane molded article having sound absorbing properties is included, a sound absorbing material having a large sound absorbing effect can be provided.

[0016] In addition, the polyurethane molded body may have a vertical incident sound absorption rate of 50% or more in the frequency range of 400 Hz to 6500 Hz. In this case, the sound absorbing material has a sound absorbing effect in a wide frequency range of 400 Hz to 6500 Hz.

[0017] In addition, the polyurethane molded body may have a vertical incident sound absorption rate of 55% or more in the frequency range of 700 Hz to 6500 Hz. In this case, the sound absorbing material has a greater sound absorbing effect in the frequency range of 700 Hz to 6500 Hz.

[0018] In addition, the polyurethane molded body may have a vertical incident sound absorption rate of 60% or more in the frequency range of 2000 Hz to 6500 Hz. In this case, the sound absorbing material has a greater sound absorbing effect in the frequency range of 2000 Hz to 6500 Hz.

[0019] In addition, the polyurethane molded body of the sound absorbing material may have a surface having concave and / or convex parts. In this case, since the surface area of ​​the polyurethane molded body is increased by the concave and / or convex parts, a greater sound absorbing effect is achieved.

[0020] In addition, the sound absorbing material may have a vertical incident sound absorption rate of 65% or more in the frequency range of 1000 Hz to 2500 Hz. In this case, the sound absorbing material has a greater sound absorption effect at frequencies from 1000 Hz to 2500 Hz. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a microscope photograph showing a polyurethane molded product 1 a according to the first embodiment of the polyurethane molded product 1 of the present invention.

[0022] Figure 2 Yes Figure 1 This is a microscopic photograph showing an enlarged portion of a polyurethane molded body 1a.

[0023] Figure 3 This is a microscope photograph showing a polyurethane molded product 1 b according to the second embodiment of the polyurethane molded product 1 of the present invention.

[0024] Figure 4 Yes Figure 3 The micrograph shown is an enlarged micrograph of a part of the polyurethane molded body 1b.

[0025] Figure 5 This is a microscopic photograph of the polyurethane molded product 1 of the present invention before the rigid polyurethane foam is crushed.

[0026] Figure 6 The polyurethane molded body 20a of the first embodiment of the polyurethane molded body 20 of the present invention is shown in FIG. 1 . (a) is a perspective view, and (b) is a cross-sectional view cut along the longitudinal direction.

[0027] Figure 7 The polyurethane molded product 20b showing the second embodiment of the polyurethane molded product 20 of the present invention, (a) is a perspective view, and (b) is a cross-sectional view cut along the longitudinal direction.

[0028] Figure 8 The polyurethane molded product 20c shows a third embodiment of the polyurethane molded product 20 of the present invention. (a) is a perspective view, and (b) is a cross-sectional view cut along the longitudinal direction.

[0029] Fig. 9 It is a polyurethane molded body 20d which shows the 4th embodiment among the polyurethane molded bodies 20 of this invention, (a) is a perspective view, and (b) is a cross-sectional view cut|disconnected along the longitudinal direction.

[0030] Fig.10 The polyurethane molded product 20e of the fifth embodiment of the polyurethane molded product 20 of the present invention is shown in FIG. 1 , wherein (a) is a perspective view and (b) is a cross-sectional view taken along the longitudinal direction.

[0031] Fig.11 (a) is a three-dimensional view of the sound absorbing material 8c of the present invention, showing the case where the convex portion 34 is a conical convex portion 34a, (b) to (d) are partial enlarged views when observed along the F direction of (a), (b) shows the case where the front end of the conical convex portion 34a is a hemispherical arc shape, (c) shows the case where the front end is a flat shape, and (d) shows the case where the front end is a sharp shape.

[0032] Fig.12 Relative to Fig.11 , the sound absorbing material 8c includes a base material 40, (a) shows a case where the polyurethane molded layer 9 sandwiches the base material 40, and (b) shows a case where the base material 40 is provided on the bottom surface side.

[0033] Fig.13 (a) is a three-dimensional view of the sound absorbing material 8c of the present invention, showing the case where the protrusion 34 is a quadrangular pyramidal protrusion 34b, (b) to (d) are partial enlarged views when observed along the G direction of (a), (b) shows the case where the front end of the quadrangular pyramidal protrusion 34b is a hemispherical arc shape, (c) shows the case where the front end is a flat shape, and (d) shows the case where the front end is a sharp shape.

[0034] Fig.14 (a) is a three-dimensional view of the sound absorbing material 8c of the present invention, showing a case where the convex portion 34 is a corrugated convex portion 34c, (b) to (d) are partial enlarged views when viewed along the J direction of (a), (b) shows a case where the front end of the corrugated convex portion 34c is a semicircular arc shape, (c) shows a case where the front end is a flat shape, and (d) shows a case where the front end is a sharp shape.

[0035] Fig.15 It is a perspective view showing a sound absorbing material 8c of the present invention, and shows a case where the projections 34 are grid-shaped projections 34d.

[0036] Fig.16 (a) is a three-dimensional view of the sound absorbing material 8c of the present invention, showing the case where the protrusion 34 is a plate-shaped protrusion 34e, (b) to (d) are partial enlarged views when observed along the K direction of (a), (b) shows the case where the front end of the plate-shaped protrusion 34e is a semicircular arc shape, (c) shows the case where the front end is a flat shape, and (d) shows the case where the front end is a sharp shape.

[0037] Fig.17(a) is a three-dimensional view showing the sound absorbing material 8d of the present invention, showing a case where a recessed portion 35 is formed, (b) to (d) are partial enlarged views (cross-sectional views) when viewed along the M direction of (a), (b) shows a case where the front end of the recessed portion is a hemispherical arc shape, (c) shows a case where the front end is a flat shape, and (d) shows a case where the front end is a sharp shape.

[0038] Fig.18 It is a perspective view showing a sound absorbing material 8e of the present invention, and shows a state where a convex portion 34 and a concave portion 35 are formed.

[0039] Fig.19 It is a diagram for explaining a first embodiment of a method for producing a polyurethane molded body 1 and a sound absorbing material 8 according to the present invention, and is a perspective view schematically showing a production process.

[0040] Fig. 20 This is a flow chart showing each step in the first embodiment of the method for producing a polyurethane molded product of the present invention.

[0041] Fig.21 It is a diagram for explaining a second embodiment of the method for producing a polyurethane molded article 1 and a sound absorbing material 8 according to the present invention, and is a perspective view schematically showing a production process.

[0042] Fig. 22 This is a flow chart showing each step of the second embodiment of the method for producing a polyurethane molded product of the present invention.

[0043] Fig.23 It is a diagram for explaining a third embodiment of the method for producing a polyurethane molded article 1 and a sound absorbing material 8 according to the present invention, and is a perspective view schematically showing a production process.

[0044] Fig.24 This is a flow chart showing each step of the third embodiment of the method for producing a polyurethane molded product of the present invention.

[0045] Fig.25 It is a view for explaining a fourth embodiment of manufacturing the polyurethane molded body 20 and the sound absorbing material 8c of the present invention, and is a perspective view schematically showing the manufacturing process.

[0046] Fig.26 This is a flow chart showing each step of the fourth embodiment of the method for producing a polyurethane molded product of the present invention.

[0047] Fig. 27 The following are the measurement results of Example 1, Example 2 and Comparative Example 1.

[0048] Fig.28 The data are comparative data of the normal-incident sound absorption coefficients of Example 1, Example 2, and Comparative Example 1 measured in a frequency range of 500 Hz or higher.

[0049] Fig.29 The following are the measurement results of Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3.

[0050] Fig.30 The data are comparative data of the normal-incident sound absorption coefficients of Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3 measured in the frequency range between 100 Hz and 3100 Hz.

[0051] Fig.31 The data are comparative data of the normal-incident sound absorption rates of Example 3 and Comparative Example 4 measured in the frequency range between 500 Hz and 2500 Hz.

[0052] Explanation of symbols

[0053] 1, 1a, 1b, 20, 20a, 20b, 20c, 20d, 20e: polyurethane molding; 2: fragment; 3: joint; 4: connecting hole; 5: end; 8, 8a, 8b, 8c, 8d, 8e, 8f, 8g, 8h, 8j: Sound-absorbing material; 26: hole; 31: surface; 33, 35: concave portion; 34: convex portion DETAILED DESCRIPTION

[0054] Hereinafter, the polyurethane molded body 1, the polyurethane molded body 20, the sound absorbing material 8, and the method for manufacturing the polyurethane molded body, which embody the present invention, will be described with reference to the accompanying drawings. In addition, the modes for implementing the invention and the accompanying drawings are used to illustrate the technical features that can be adopted by the present invention. The present invention is not limited to these. The structures of the devices described in the accompanying drawings are not limited to these, but are merely illustrative examples.

[0055] <Common Configuration in the Polyurethane Molded Product 1 of the First Embodiment>

[0056] The polyurethane molded body 1 and the polyurethane molded body 20 of the first embodiment of the present invention are described. Hereinafter, the polyurethane molded body 1 and the polyurethane molded body 20 are collectively referred to as the polyurethane molded body 1, etc. Each embodiment will be described later, and the common structure will be described first. Figures 1 to 4 As shown, the polyurethane molded body 1 includes polyurethane segments 2, a connecting portion 3 where a plurality of adjacent polyurethane segments 2 are connected to each other, and a connecting hole 4. The segments 2 are molded in a state where at least a portion is in a meandering state and at least a portion has an end 5 separated from an adjacent segment 2.

[0057] As an example, the fragment 2 is a fragment of the shell 11 of the monomer 10 forming the rigid polyurethane foam. Figures 1 to 4In the figure, as an example, the material of the polyurethane molded body 1 is obtained by crushing the rigid polyurethane foam, and is a microscope photograph of compression molding. In addition, the material of the polyurethane molded body 1 is not limited to rigid polyurethane, as long as it is made of polyurethane. In addition, the polyurethane molding material 21 as the polyurethane fragment 2 does not need to be a crushed material, as long as it is of a size described later. In addition, as Figure 5 As shown, the rigid polyurethane foam is a polyurethane foam having individual units 10 of an independent structure.

[0058] like Figure 2 , Figure 4 As shown, the connecting holes 4 appear as black shadows, but are not closed by the segments 2. The connecting holes 4 are interlaced and connected to each other in the polyurethane molded body 1, etc. The segments 2 are not planar but are irregularly bent and are integrally formed by being combined with other adjacent segments 2 at the joint 3.

[0059] like Figures 1 to 4 As shown, as an example, the polyurethane molded body 1 is a monomer 10 of a rigid polyurethane foam, wherein the shell 11 is crushed to form a fragment 2, and the fragment 2 is compressed while forming a joint 3 with an adhesive 22. The manufacturing method will be described later. In addition, the adhesive 22 suitable for each manufacturing method will also be described later. Figure 5 This is a microscope photograph showing the state of the rigid polyurethane foam before being crushed. Figure 5 is with Figure 1 and Figure 3 Same magnification.

[0060] like Figure 5 As shown, the rigid polyurethane foam before crushing is formed with monomers 10 surrounded by shells 11. Each monomer 10 is in an independent state, and compared with the state after crushing, the monomer 10 appears clearly and is difficult to communicate with the adjacent monomers 10. Furthermore, the range of the monomer 10 surrounded by the shell 11 before crushing is large. In contrast, Figure 1 and Figure 3 The polyurethane molded body 1 shown is in a state where the outer shell 11 is divided and compressed and the monomer 10 is flattened. The outer shell 11 is divided and fragmented to form the fragment 2, and the fragment 2 is compressed and irregularly bent. In addition, the fragment 2 is connected by forming a connecting portion 3 with an adhesive 22 to form a connecting hole 4, and then integrated.

[0061] In addition, if Figure 2 , Figure 4 As shown, at least a portion of the end portion 5 of the segment 2 is formed in a corrugated shape and is in a state of protruding toward the communicating hole 4, forming a free end state that is not constrained.

[0062] In addition, if Figures 2 to 4As shown, the segment 2 has a defect 6 in at least a portion. The portion that is opened and blackened in a portion of the segment 2 is the defect 6. The defect 6 is formed in one segment 2 differently from the communicating hole 4. The defect 6 allows adjacent regions across the segment 2 to communicate with each other.

[0063] In addition, the air permeability of the polyurethane molded body 1 is 4.68 cm 3 / cm 2 s or more and 6.93cm 3 / cm 2 ·s or less. The air permeability is the result of measurement based on "JIS L1096 Textile and Knitted Fabrics Test Methods". The air permeability is obtained by the communicating holes 4 and the defective parts 6.

[0064] Next, refer to Fig.28 and Fig.30 , the vertical incident sound absorption rate of the polyurethane molded body 1, etc. is described. Fig.28 and Fig.30 In the embodiment, the polyurethane molded product 1 and the like correspond to A and B. The polyurethane molded product 1 and the like have a vertical incident sound absorption rate of 50% or more in the frequency range of 400 Hz to 6500 Hz. Fig.28 As shown, the polyurethane molded body 1 and the like have a vertical incident sound absorption rate of 55% or more in the frequency range of 700 Hz to 6500 Hz. In addition, the polyurethane molded body 1 and the like have a vertical incident sound absorption rate of 60% or more in the frequency range of 2000 Hz to 6500 Hz. The measurement method of the vertical incident sound absorption rate and the detailed measurement results are described in the description of each embodiment and the examples.

[0065] <Effects of the Common Configuration in the Polyurethane Molded Product 1 of the First Embodiment>

[0066] According to the common structure of the polyurethane molded body 1 described above, the following effects are achieved. Figures 1 to 4 As shown, the polyurethane molded body 1 etc. has a connecting hole 4 connecting the segments 2 and the connecting portion 3, so it has air permeability. Furthermore, the segments 2 are connected to each other at the connecting portion 3, at least a part is in a zigzag state, and at least a part has an end 5 separated from the adjacent segment 2. Therefore, the vibration of the sound of the polyurethane molded body 1 etc. is attenuated, and a sound absorbing effect is achieved.

[0067] Furthermore, since the end portion 5 of the segment 2 is formed in a corrugated shape and protrudes toward the communicating hole 4, it is easy to attenuate the vibration of sound, thereby achieving a greater sound absorbing effect.

[0068] Furthermore, since the segment 2 has the defective portion 6 in part in addition to the communicating hole 4, the air permeability can be further improved, the vibration of the transmitted sound can be dispersed in a wider range, and the sound absorbing effect can be increased.

[0069] In addition, since the air permeability of the polyurethane molded product 1 and the like is within an appropriate range, a sound absorbing effect is achieved, and a heat insulating effect is achieved.

[0070] Next, the sound absorption effect of the polyurethane molded body 1 and the like will be described. The polyurethane molded body 1 and the like have a vertical incident sound absorption rate of 50% or more in the frequency range of 400 Hz to 6500 Hz, and thus have a sound absorption effect in a wide frequency range. In addition, the polyurethane molded body 1 and the like have a vertical incident sound absorption rate of 55% or more in the frequency range of 700 Hz to 6500 Hz, and thus have a greater sound absorption effect in the frequency range of 700 Hz to 6500 Hz. Furthermore, in the frequency range of 2000 Hz to 6500 Hz, the vertical incident sound absorption rate is 60% or more, and thus have a greater sound absorption effect in the frequency range of 2000 Hz to 6500 Hz.

[0071] <Description of Each Embodiment of Polyurethane Molded Product 1 of First Embodiment>

[0072] Next, refer to Figures 1 to 4 , a polyurethane molded body 1a as a first embodiment of the polyurethane molded body 1 and a polyurethane molded body 1b as a second embodiment are described. In the polyurethane molded body 1a of the first embodiment, the polyurethane molding material 21 as the polyurethane fragment 2 is a material that has been previously passed through a sieve with a mesh size of 2 mm. On the other hand, in the polyurethane molded body 1b of the second embodiment, the polyurethane molding material 21 as the fragment 2 is a material that has not previously been passed through a sieve with a mesh size of 2 mm.

[0073] The polyurethane molding material 21 is, for example, a material obtained by crushing a rigid polyurethane foam, and the particle sizes of the polyurethane molded body 1a and the polyurethane molded body 1b are different. Alternatively, the polyurethane molding material 21 may be a material formed by other methods instead of crushing.

[0074] Figure 1 and Figure 2 is a microscope photograph showing a polyurethane molded body 1a. Figure 3 and Figure 4 1 is a microscope photograph showing a polyurethane molded body 1b. As an example, each of the polyurethane molded bodies 21 is obtained by compressing a pulverized hard polyurethane foam. Figure 1 and Figure 3 The magnification is the same. Figure 1 and Figure 3 It can be seen that Figure 1As shown, the shell 11 of the monomer 10 of the polyurethane molded body 1a is divided at a large ratio, and most of it is divided into segments 2, and the segments 2 are thin. The connecting portion 3 connects the segments 2, so that the apparent units 12 including the connecting holes 4 are formed roughly evenly. Here, the apparent unit 12 refers to the range that looks like a unit by forming a part of the shell 11 by the segment 2, but since the outline is unclear, the so-called apparent temporary name is adopted. Figures 1 to 4 The apparent cells 12 shown represent a rough outline.

[0075] In addition, if Figure 1 and Figure 2 As shown, in the polyurethane molded body 1a, compared with the polyurethane molded body 1b, most of the end portion 5 is formed in a corrugated shape and protrudes toward the through hole 4. The segment 2 is flattened and bent, and a fold line 7 is formed.

[0076] like Figure 3 As shown, monomers 10 remain in a part of the polyurethane molded body 1b, and the interval between adjacent communicating holes 4 is wider than that of the polyurethane molded body 1a. The remaining monomers 10 and the apparent units 12 formed by the combination part 3 and the segment 2 are mixed and become uneven. However, although the proportion of the apparent units 12 in the polyurethane molded body 1b is less than that of the polyurethane molded body 1a, the shell 11 of the monomer 10 is divided to form the segment 2, and the combination part 3 and the communicating hole 4 are formed. In addition, a defective part 6 is formed in a part of the segment 2.

[0077] <Effects of Each Embodiment of the Polyurethane Molded Product 1 of the First Embodiment>

[0078] As described above, the polyurethane molded product 1a of the first embodiment and the polyurethane molded product 1b of the second embodiment have the following effects. The property values ​​of the polyurethane molded product 1a and the polyurethane molded product 1b are described in the examples described below, but both have both heat insulation and sound absorption properties.

[0079] The polyurethane molded body 1a has a smaller material before compression than the polyurethane molded body 1b, so the density after compression molding is high, and the segments 2, the connecting parts 3, and the communicating holes 4 are more uniformly formed. Therefore, even when the polyurethane molded body 1a is partially cut out and used, the heat insulation and sound absorption properties are more stable.

[0080] In addition, the density of the polyurethane molded body 1b after compression molding is low, which can achieve lightweight. In addition, the sound absorption effect can be further improved. It should be noted that the structure and effect of the polyurethane molded body 1 described above are also the same as the polyurethane molded layer 9 in the polyurethane molded body 20 described later.

[0081] <Structure and Effects of Polyurethane Molded Article 20 of First Embodiment>

[0082] Next, the polyurethane molded body 20 according to the first embodiment of the present invention will be described. Figures 6 to 10 As shown, the polyurethane molded body 20 includes a polyurethane molded layer 9 and a substrate 40. The polyurethane molded layer 9 corresponds to the reference Figures 1 to 4 The polyurethane molded body 1 described herein comprises segments 2 made of polyurethane, a joint 3 where a plurality of adjacent segments 2 are joined to each other, and a connecting hole 4. The segments 2 are molded in a state where at least a portion is in a tortuous state, and at least a portion is in a state where an end portion 5 is separated from an adjacent segment 2. The polyurethane molded layer 9 and the substrate 40 are at least partially joined to each other. The polyurethane molded layer 9 and the substrate 40 are integrally molded by a method for manufacturing a polyurethane molded body described later. Alternatively, the polyurethane molded layer 9 and the substrate 40 are bonded to each other with an adhesive 22. The substrate 40 comprises, for example, MDF. MDF is a medium density fiberboard, which means a sheet material. In addition, MDF is used in this example, but other materials may also be used as long as they have a reinforcing effect and may also be used for the substrate 40.

[0083] According to the polyurethane molded body 20 of the first embodiment of the present invention described above, the following common effects are achieved in each embodiment. The polyurethane molded body 20 is in a state where at least a portion of the polyurethane molded layer 9 and the substrate 40 are bonded to each other, so the strength is increased by the substrate 40. In addition, the polyurethane molded body 20 can improve the sound insulation or sound absorption according to the shape. Therefore, the polyurethane molded body 20 can be used as a heat insulating material and / or a sound absorbing material.

[0084] Next, various embodiments of the polyurethane molded article 20 will be described. Figure 6 , a polyurethane molded body 20a as a first embodiment of the polyurethane molded body 20 is described. The polyurethane molded layer 9 of the polyurethane molded body 20a is in a state where the top surface 9a and the bottom surface 9b are covered by the substrate 40. In addition, the side surface may also be exposed. Figure 6 As shown in (b), the polyurethane molded body 20a is integrally molded in a manner that the substrate 40 is combined with the top surface 9a and the bottom surface 9b of the polyurethane molded layer 9. Alternatively, the substrate 40 is bonded to the top surface 9a and the bottom surface 9b of the polyurethane molded layer 9. It should be noted that the polyurethane molded body 20a and the polyurethane molded body 20b described below both illustrate a three-layer structure in the thickness direction, but a two-layer structure of the polyurethane molded layer 9 and the substrate 40 may also be used.

[0085] According to the polyurethane molded body 20a of the first embodiment of the polyurethane molded body 20 described above, the following effects are achieved. Figure 6As shown, the polyurethane molded body 20a is in a state where the top surface 9a and the bottom surface 9b of the polyurethane molded layer 9 are sandwiched by the substrate 40. Therefore, the strength of the polyurethane molded body 20a is high. In addition, the polyurethane molded body 20a has sound insulation because the polyurethane molded layer 9 is sandwiched by the substrate 40.

[0086] Next, refer to Figure 7 , a polyurethane molded body 20b as a second embodiment of the polyurethane molded body 20 is described. The substrate 40 of the polyurethane molded body 20b is in a state where the top surface 40a and the bottom surface 40b are covered by the polyurethane molded layer 9. In addition, the side surface may also be exposed. Figure 7 As shown in (b), the polyurethane molded body 20b is integrally molded by bonding the polyurethane molded layer 9 to the top surface 40a and the bottom surface 40b of the substrate 40. Alternatively, the polyurethane molded layer 9 is bonded to the top surface 40a and the bottom surface 40b of the substrate 40.

[0087] According to the polyurethane molded body 20b of the second embodiment of the polyurethane molded body 20 described above, the following effects are achieved. Figure 7 As shown, the top surface 40a and the bottom surface 40b of the polyurethane molded body 20b are covered with the polyurethane molded layer 9. Therefore, the polyurethane molded body 20b has sound absorption properties. In addition, the strength is increased by the base material 40.

[0088] Next, refer to Figure 8 , a polyurethane molded body 20c as a third embodiment of the polyurethane molded body 20 is described. The substrate 40 of the polyurethane molded body 20c is in a state where the periphery is covered with the polyurethane molded layer 9. As an example, the substrate 40 is in a rectangular parallelepiped shape. Figure 8 As shown in (b), the polyurethane molded body 20c is formed by covering the base material 40 in the thickness direction and the length direction with the polyurethane molded layer 9. Although not shown, the cross-sectional view cut along the width direction also shows that the base material 40 is covered with the polyurethane molded layer 9 in the thickness direction and the width direction.

[0089] According to the polyurethane molded body 20c of the third embodiment of the polyurethane molded body 20 described above, the following effects are achieved. Figure 8 As shown, the outer periphery of the base material 40 of the polyurethane molded body 20c is covered with the polyurethane molded layer 9, and the polyurethane molded layer 9 is exposed at the outer periphery. Therefore, the polyurethane molded body 20c has sound absorbing properties.

[0090] Next, refer to Fig. 9 , a polyurethane molded body 20d according to a fourth embodiment of the polyurethane molded body 20 will be described. Fig. 9 As shown, the polyurethane molded layer 9 of the polyurethane molded body 20d is in a state where the outer periphery is covered by the base material 40. Fig. 9As shown in (b), the polyurethane molded body 20d is formed by covering the polyurethane molded layer 9 with the substrate 40 in the thickness direction and the length direction. Although not shown in the figure, in the cross-sectional view cut along the width direction, the polyurethane molded layer 9 is also covered with the substrate 40 in the thickness direction and the width direction. Fig. 9 As shown in the example of (b), the base 40 includes a bottom box 40c and a cover 40d, and the polyurethane molded body 20b is formed by integrally molding a polyurethane molded layer 9 inside the base 40. Alternatively, the polyurethane molded layer 9 is bonded to the inner side of the base 40.

[0091] According to the polyurethane molded article 20d of the fourth embodiment of the polyurethane molded article 20 described above, the following effects are achieved. Fig. 9 As shown, the outer periphery of the polyurethane molded layer 9 is covered with the base material 40, so the strength of the polyurethane molded body 20d is increased. In addition, the polyurethane molded layer 9 can be prevented from falling off.

[0092] Next, refer to Fig.10 , a polyurethane molded body 20e as a fifth embodiment of the polyurethane molded body 20 will be described. Fig.10 As shown, the polyurethane molded layer 9 of the polyurethane molded body 20e is in a state where the side surface is covered by the substrate 40 and the top surface 9a and the bottom surface 9b are exposed. Fig.10 As shown in (a), the substrate 40 is a frame with a through hole inside, and the polyurethane molded body 20e is formed by integrally molding the polyurethane molded layer 9 inside the substrate 40. Alternatively, the polyurethane molded layer 9 is bonded inside the substrate 40.

[0093] According to the polyurethane molded body 20e of the fifth embodiment of the polyurethane molded body 20 described above, the following effects are achieved. Fig.10 As shown, in the polyurethane molded body 20e, the side of the polyurethane molded layer 9 is covered by the substrate 40, the top surface 9a and the bottom surface 9b are exposed, and the side is covered by the substrate 40. Therefore, the strength of the polyurethane molded body 20e is increased. In addition, the top surface 9a and the bottom surface 9b of the polyurethane molded layer 9 are exposed, so it has sound absorption. Furthermore, it is possible to prevent the polyurethane molded layer 9 from falling off from the side.

[0094] <Structure and Effect of Sound Absorbing Material 8 of Second Embodiment of the Present Invention>

[0095] Next, the sound absorbing material 8 according to the second embodiment of the present invention will be described. Fig.19 As shown in (c), the sound absorbing material 8 may be used directly as the polyurethane molded body 1, or may be embedded in a predetermined frame or the like. Figures 11 to 18 As shown, it is also possible to have a surface with concave and / or convex parts, and there is no particular limitation on the shape and size. Fig.28 and Fig.30, the relationship between the frequency and the vertical incident sound absorption rate of the sound absorbing material 8 is described. Fig.28 As shown, the sound absorbing material 8 of the polyurethane molded body 1 has a vertical incident sound absorption rate of 55% or more in the frequency range of 700 Hz to 6500 Hz. In addition, in the frequency range of 2000 Hz to 6500 Hz, the vertical incident sound absorption rate is 60% or more. Fig.28 In the figure, A represents the polyurethane molded product 1a, B represents the polyurethane molded product 1b, and C represents the rigid polyurethane foam.

[0096] In addition, if Fig.30 As shown, the sound absorbing material 8 of the polyurethane molded body 1 has a vertical incident sound absorption rate of more than 50% in the frequency range of 400 Hz to 6500 Hz. In addition, the vertical incident sound absorption rate of the sound absorbing material 8 rises sharply from 100 Hz and reaches a peak near 700 Hz to 800 Hz. Fig.30 In the Fig.28 Similarly, D stands for rock wool and E stands for glass wool.

[0097] As described above, the sound absorption rate of the sound absorbing material 8 based on the polyurethane molded body 1 increases sharply as the frequency increases from 100 Hz, and the sound absorption rate of the sound absorbing material 8 at vertical incidence is more than 50% in the frequency range of 400 Hz to 6500 Hz. The sound of human conversation is generally 250 Hz to 4000 Hz. The sound absorbing material 8 has a sound absorption effect on the sound generated by human conversation. In addition, the sound absorption material 8 has a sound absorption rate of more than 55% at vertical incidence in the frequency range of 700 Hz to 6500 Hz, and the sound absorption effect is even greater. Moreover, the sound absorbing material 8 has a greater sound absorption effect in the high-frequency range of 2000 Hz to 6500 Hz. About Fig.28 The vertical incident sound absorption rate shown is described in detail in the examples. The vertical incident sound absorption rate described above is a measured value when the sound absorbing material 8 is a substantially rectangular flat plate. The following describes the case where the surface has irregularities.

[0098] <Description of the Sound Absorbing Material 8 Having Concavoconvex Shape>

[0099] Next, refer to Figures 11 to 18 , the sound absorbing materials 8c to 8j among the sound absorbing materials 8 based on the polyurethane molded body 1 are described. The sound absorbing materials 8c to 8g have a surface 31 having a concave portion 33 and / or a convex portion 34. The sound absorbing materials 8h and 8j have a surface 31 having a concave portion 35 and / or a convex portion 34. As an example, Fig.11As shown in FIG. 1 and FIG. 2 , the case where the sound absorbing material 8 has a first surface 31a and a second surface 31b having a predetermined thickness and facing each other is described as an example. At least one of the first surface 31a and the second surface 31b has a concave portion 33 and / or a convex portion 34, or a concave portion 35 and / or a convex portion 34. Fig.14 As shown in FIG. 1 , the concave portion 33 represents the valley between the convex portion 34 and the convex portion 34. Fig.17 As shown in FIGS. 1 and 1B , the recessed portion 35 is a recessed portion formed by being recessed from the surface 31 .

[0100] The convex portions 34 may be arranged regularly in a lattice shape, for example, or may be formed randomly. Similarly, the concave portions 35 may be arranged regularly in a lattice shape, for example, or may be formed randomly. Examples of the concave portions 33, 35, and convex portions 34 are described below.

[0101] Reference Fig.11 The sound absorbing material 8c is described. The sound absorbing material 8c shows a case where the convex portion 34 is a conical convex portion 34a. Fig.11 As shown in (a), the conical protrusions 34a are arranged in a grid pattern. Fig.11 As shown in FIG. 2( b ), the front end of the conical protrusion 34 a may be hemispherical with roundness, or may be Fig.11 (c) is a plane, or it can be Fig.11 (d) shows a sharp shape. The relationship between the thickness L and the height h of the convex portion can be set arbitrarily. Moreover, the thickness L can also be greater than the height h of the convex portion. The same applies to the other convex portions 34 described below. The intervals between adjacent conical convex portions 34a can be equal or random. In addition, Fig.11 In the example shown in FIG. 1 , the convex portion 34 is a conical convex portion 34a, but the convex portion 34 may also be a cylindrical portion. Fig.11 As shown, the protrusion 34 is a conical protrusion 34a.

[0102] Fig.12 The example shown represents the Fig.11 In the example shown, the polyurethane molded layer 9 as a part of the sound absorbing material 8 c is bonded to the base material 40 . Fig.12 The example shown in (a) shows a case where the base material 40 is sandwiched between the polyurethane molded layer 9 having the conical convex portion 34 a in the thickness direction and the polyurethane molded layer 9 of the lower layer. Fig.12 The example shown in (b) shows a case where the lower layer of the polyurethane molded layer 9 having the conical convex portion 34 a in the thickness direction is the base material 40 .

[0103] Reference Fig.13 , the sound absorbing material 8d is described. The sound absorbing material 8d represents the case where the convex portion 34 is a quadrangular pyramid convex portion 34b. Fig.13 (a) shows, with Fig.11 Similarly to the example of , the quadrangular pyramid-shaped protrusions 34b are arranged in a grid pattern. Fig.13 As shown in FIG. 2( b ), the front end of the quadrangular pyramid-shaped protrusion 34 b may be hemispherical with roundness, or may be as shown in FIG. Fig.13 (c) is shown as a plane, or it can be Fig.13 (d) shows a sharp shape. The intervals between the adjacent quadrangular pyramid-shaped protrusions 34b can be equal or random. Fig.13 In the example shown, the convex portion 34 is a quadrangular pyramid-shaped convex portion 34 b , but the convex portion 34 may be a polygonal pyramid other than a quadrangular pyramid, or may be a polygonal column.

[0104] Reference Fig.14 , the sound absorbing material 8e is described. The convex portion 34 of the sound absorbing material 8e is a corrugated convex portion 34c, as shown in FIG. Fig.14 As shown in (a), the convex portion 34c is formed continuously in one direction and is formed into a wave shape with the concave portion 33 interposed therebetween. The intervals between the adjacent wavy convex portions 34c can be equal intervals or random. Fig.14 In the example shown, adjacent wave-shaped convex portions 34c are formed independently of each other, but they may be connected with each other in a smooth curve via the concave portion 33. Fig.14 As shown in (b), the front end of the corrugated convex portion 34c may be semicircular with roundness, or may be Fig.14 (c) is a plane, or it can be Fig.14 (d) shows a sharp shape.

[0105] Reference Fig.15 , the sound absorbing material 8f is described. The sound absorbing material 8f shows a case where the protrusion 34 is a grid-shaped protrusion 34d. Fig.14 The wave-shaped convex portions 34c described above are formed in a grid-like manner so as to intersect each other. The intervals between the adjacent grid-shaped convex portions 34d may be equal intervals or may be random. Fig.15 In the example shown, the adjacent lattice-shaped protrusions 34d are formed independently of each other, but they may be connected with each other in a smooth curve via the concave portion 33. Fig.14 The same is true for the wave-shaped convex portion 34c described above.

[0106] Reference Fig.16 , the sound absorbing material 8g is described. The sound absorbing material 8g represents the case where the protrusion 34 is a plate-shaped protrusion 34e. Fig.16As shown in (a), the plate-like protrusions 34e are formed into a group with a plurality of recesses 33, and the extension directions of the plate-like protrusions 34e between adjacent groups are formed in a manner that differs by 90 degrees. The adjacent plate-like protrusions 34e can be evenly spaced or randomly spaced. In addition, the gaps between the groups can be evenly spaced or randomly spaced. Fig.16 As shown in (b), the front end of the plate-like protrusion 34e can be semicircular with roundness, or can be Fig.16 (c) is a plane, or it can be Fig.16 (d) shows a sharp shape.

[0107] Reference Fig.17 , the sound absorbing material 8h is described. The sound absorbing material 8h represents the case where only the concave portion 35 is formed. Fig.17 As shown in (a), the recess 35 is formed by being recessed from the first surface 31a. The recess 35 is, for example, conical. The depth d of the recess 35 may be the same as or different from the height h of the convex portion 34. In addition, the recess 35 may be cylindrical, or may be a polygonal column or a polygonal pyramid. The recesses 35 are shown as an example arranged in a grid, but may also be random. Fig.17 As shown in (b), the front end of the recess 35 can be in a hemispherical shape with a rounded shape, or it can be in a hemispherical shape with a rounded shape. Fig.17 (c) is a plane, or it can be Fig.17 (d) shows a sharp shape.

[0108] Reference Fig.18 , the sound absorbing material 8j is described. The sound absorbing material 8j shows an example in which the conical convex parts 34a and the concave parts 35 are arranged alternately in a lattice. The conical convex parts 34a protrude from the first surface 31a, and the concave parts 35 are formed by being recessed from the first surface 31a. The example in which the conical convex parts 34a and the concave parts 35 are arranged in a lattice is shown, but they may be arranged randomly. In addition, the shape of the front end of the conical convex part 34a is similar to that of the reference Fig.11 (b) to Fig.11 (d) The shape is the same as that described above, and the shape of the front end of the recess 35 is the same as that of the reference Fig.17 (b) to Fig.17 (d) The shapes described are the same.

[0109] The above-described sound absorbing materials 8c to 8j have the following characteristics. The sound absorbing material 8c will be described as a representative example. The detailed description will be given in the following embodiment. Fig.31 The third embodiment shown is a sound absorbing material 8c. The sound absorbing material 8c has a sound absorption rate of 65% or more at a vertical incidence between 1000 Hz and 2500 Hz. Furthermore, the sound absorption rate of 70% or more at a vertical incidence between 1400 Hz and 1800 Hz.

[0110] In addition, the example described above describes an example in which the convex part 34, the concave part 33, and the concave part 35 are formed only on the first surface 31a, but they can also be formed on the second surface 31b, or on both the first surface 31a and the second surface 31b. In addition, the convex part 34 or the concave part 33, and the concave part 35 of different shapes can also be formed on the first surface 31a and the second surface 31b. In addition, the case where the sound absorbing material 8 is in a plate shape is described as an example, but it is not limited to this. For example, the sound absorbing material 8 can be spherical, or it can be a polygonal pyramid, a polygonal column, a cone, or any other shape.

[0111] <Effect of sound absorbing material having concavoconvex shape>

[0112] According to the above-described sound absorbing material 8c to the sound absorbing material 8j, the following effects are achieved. For the sound absorbing material 8c to the sound absorbing material 8j, the surface area of ​​the polyurethane molded body 1 and the like is increased by the concave portion 33 and / or the convex portion 34, thereby achieving a greater sound absorbing effect. That is, the surface area of ​​the polyurethane molded body 1 is increased by at least any one of the concave portion 33, the concave portion 35, and the convex portion 34, thereby achieving a greater sound absorbing effect. If the area of ​​the polyurethane molded body 1 is increased, there are more passages for air that transmits the vibration of sound, and the sound absorbing effect becomes greater than that of a flat plate with no concave and convex surfaces.

[0113] In addition, the shape of the convex portion 34 is changed from Fig.11 The sound absorbing material 8c shown to Fig.15 The sound absorbing material 8f shown, and Fig.18 In the case of the sound absorbing material 8e shown in the figure, each side surface of the convex portion 34 is inclined at a predetermined angle relative to the thickness direction, so that air that transmits sound can be incident from multiple angles. Fig.17 The sound absorbing material 8h shown and Fig.18 In the case of the sound absorbing material 8j shown, since the inner surface of the recess 35 is inclined at a predetermined angle, air that transmits sound can enter from multiple angles. Therefore, the sound absorbing materials 8c to 8j have a greater sound absorbing effect.

[0114] Furthermore, for example, when the surface 31 having the convex portions 34 is used in a state of being in contact with another member such as a wall surface, air passes between the convex portions 34, so that air permeability can be ensured.

[0115] Furthermore, refer to Fig.12 The sound absorbing material 8c described above is formed by combining the polyurethane molded layer 9 and the base material 40, and thus has the same effects as the polyurethane molded body 20a described above.

[0116] In addition, if Fig.31As shown in FIG. 1 , the sound absorbing material 8c has a sound absorption rate of 65% or more at a vertical incidence between 1000 Hz and 2500 Hz, and further, a sound absorption rate of 70% or more at a vertical incidence between 1400 Hz and 1800 Hz. Therefore, the sound absorbing material 8c has a greater sound absorption effect at a frequency between 1000 Hz and 2500 Hz. Furthermore, it has a greater sound absorption effect at a frequency between 1400 Hz and 1800 Hz.

[0117] <<Description of the method for producing a polyurethane molded article>>

[0118] Next, refer to Figures 19 to 26 , a method for manufacturing a polyurethane molded body of the third embodiment of the present invention is described. The method for manufacturing a polyurethane molded body is a method for manufacturing a polyurethane molded body 1, a polyurethane molded body 20, and a sound absorbing material 8. First, the common steps of all the methods for manufacturing polyurethane molded bodies are described. The method for manufacturing a polyurethane molded body may include a preliminary step S0 of crushing a polyurethane foam to form a polyurethane fragment 2 to form a polyurethane molding material 21 before the first step S1. The preliminary step S0 is optional. That is, there is a case where the preliminary step S0 is combined in a series of manufacturing steps and a case where the polyurethane molding material 21 that has been crushed is used and started from the first step S1 described later. The polyurethane foam is, for example, a rigid polyurethane foam.

[0119] like Fig. 20 , Fig. 22 , Fig.24 and Fig.26 As shown, when the preliminary step S0 is provided, the preliminary step S0 includes the step P1 and the step P2. The first step S1 includes the step P3 and the step P4. The second step S2 includes the step P5 and the step P6.

[0120] The case where the preparatory step S0 is provided is described below. The polyurethane molding material 21 is, for example, a hard polyurethane foam. Figure 5 As shown in FIG. 1 , the rigid polyurethane foam before pulverization is formed into a single body 10 surrounded by a shell 11. The rigid polyurethane foam is used as an example of a material discarded as industrial waste or a scrap material generated in a production process. In this case, Fig.19 and Fig. 20 In the example shown, the method for producing a polyurethane molded article comprises a step P1 of recovering a rigid polyurethane foam as a recycling material and a step P2 of pulverizing the rigid polyurethane foam.

[0121] Step P2 is a step of crushing the rigid polyurethane foam to form fragments 2 by fragmenting the shell 11 of the monomer 10 that forms the rigid polyurethane foam. In step P2, the rigid polyurethane foam is crushed into a specified size. As shown in Example 1 described later, the polyurethane molding material 21 can crush the rigid polyurethane foam and pass it through a sieve with a mesh of 2 mm in advance. As already explained, the state of the molded fragments 2, the joint 3, the connecting hole 4 and the defective part 6 is different according to the size of the crushed fragments. It should be noted that, hereinafter, the molding material used in the present manufacturing method, that is, the rigid polyurethane foam, which is not processed in advance into a specified size without crushing processing, is collectively referred to as polyurethane molding material 21. In addition, in the case where the rigid polyurethane foam is not waste, etc., step P1 is omitted. In addition, in the case where the polyurethane molding material 21 is a material that has been crushed in advance or has a specified fine size, step P2 of crushing the rigid polyurethane foam is omitted.

[0122] When the method for producing a polyurethane molded body includes the preparatory step S0, the method proceeds to the first step S1 after the preparatory step S0. When the method does not include the preparatory step S0, the method skips the preparatory step S0 and starts from the first step S1. Fig.19 As shown in FIG. 1 , the method comprises a first step S1 of mixing a polyurethane molding material 21 and an adhesive 22 and putting the mixture into a molding die 24 and a molding die 25, and a second step S2 of performing compression molding in the molding die 24 and the molding die 25. In the second step S2, a connecting portion 3 and a connecting hole 4 are formed where a plurality of adjacent segments 2 are connected to each other. At least a portion of the segment 2 forms an end portion 5 separated from an adjacent segment 2.

[0123] The first step S1 is described below. Fig.19 As shown in FIG. 1 , the first step S1 includes step P3 and step P4. Fig.19 In the example shown in (a), process P3 is to put the polyurethane molding material 21 and the adhesive 22 into the mixing container 41, and vibrate the mixing container 41 in multiple directions to mix. The adhesive 22 is selected and used to be suitable for each embodiment described later. Process P4 is partially different according to the embodiment. In the first embodiment to the third embodiment, process P4 is a process of putting the polyurethane molding material 21 and the like into the molding die 24 and the molding die 25. Process P4 in the fourth embodiment is described later.

[0124] The second step S2 is described. The second step S2 includes a step P5 of inserting the polyurethane molding material 21 mixed with the adhesive 22 into the molding dies 24 and 25 and then performing compression molding, and a step P6 of taking out the molded product. The step P5 is different in each embodiment. Fig.11 Sound absorption shown Material 8c to Fig.18 In the sound absorbing material 8j shown in the figure, the molding die 25 It is formed with concave and convex shapes.In the second step S2 , the polyurethane molding material 21 and the like are formed with respective concavo-convex shapes on the molding die 25 .

[0125] <Description of First Embodiment in Method for Producing Polyurethane Molded Article>

[0126] Next, the method for producing a polyurethane molded body will be described according to the embodiment. As already described, the optional preparatory step S0 is common except for the third embodiment, so the description is omitted. In addition, in the first step S1, the type of adhesive 22 used is described. Fig.19 and Fig. 20 , a first embodiment of the method for producing a polyurethane molded body will be described. The first to third embodiments are methods for producing a polyurethane molded body 1 and a sound absorbing material 8, and the fourth embodiment is a method for producing a polyurethane molded body 20 and a sound absorbing material 8c.

[0127] The first embodiment of the method for producing a polyurethane molded body is described. The type of adhesive 22 used in step P3 in the first step S1 is described. The adhesive 22 can be a moisture-curing adhesive, a thermosetting adhesive, or a hot melt adhesive. It is particularly preferred to use a moisture-curing adhesive. This is because by introducing the water vapor 28 heated in step P5 in the second step S2 described later, curing can be performed quickly.

[0128] Next, refer to Fig.19 (b) and Fig. 20 , the second step S2 is described. Step P5 in the second step S2 is a step of compression molding the polyurethane molding material 21 and the like put into the molding die 24 and the molding die 25 by the molding die 24 and the molding die 25. In step P5, compression molding is performed while introducing heated water vapor 28 into the holes 26 formed on each side of the molding die 24. The pressure during the compression molding of step P5 is 0.1 MPa or more. The pressurization time is between 3 minutes and 30 minutes.

[0129] In step P5, the polyurethane molded body 1 forms connecting portions 3 by connecting adjacent segments 2 to each other, and forms connecting holes 4 connecting the segments 2 and the connecting portions 3. In addition, at least a portion of the segment 2 is bent and at least a portion is separated from the adjacent segment 2.

[0130] Then, if Fig.19 (c) and Fig. 20 As shown, there is a step P6 for taking out the molded product, and a step P7 for cutting out the molded product according to the application.

[0131] <Description of Second Embodiment in Method for Producing Polyurethane Molded Article>

[0132] Next, a second embodiment of the method for producing a polyurethane molded article will be described. Fig.21 and Fig. 22 The type of adhesive 22 used in step P3 of the first step S1 is described. The adhesive 22 may be a thermosetting adhesive or a hot melt adhesive. In the first embodiment of the method for manufacturing a polyurethane molded body, in step P5 of the second step S2, the polyurethane molding material 21 is compressed while the heated steam 28 is introduced. In contrast, Fig.21 and Fig. 22 As shown, in step P5, instead of introducing heated steam 28, a high temperature compression method is adopted in which the polyurethane molding material 21 and the like are compressed in a state of being heated to a high temperature.

[0133] Since the high temperature compression method does not introduce water vapor 28 in the second step S2, there is not enough water in the molding die 24 and the molding die 25, and the moisture curing adhesive cannot be used in the step P3. However, as in the first embodiment of the method for manufacturing a polyurethane molded body, the molded body can be manufactured with simple equipment compared to the method for manufacturing a molded body in which heated water vapor 28 is introduced. The compression molding of the step P5 is performed at a temperature of 120° C. to 160° C. for a time of 5 minutes to 30 minutes. The pressure during compression is between 0.1 MPa and 0.5 MPa.

[0134] <Description of the Third Embodiment in the Method for Producing Polyurethane Molded Article>

[0135] Next, refer to Fig.23 and Fig.24 , a third embodiment of the method for manufacturing a polyurethane molded body is described. The type of adhesive 22 used in step P3 in the first step S1 is described. The adhesive 22 can use a moisture-curing adhesive, a thermosetting adhesive, or a hot melt adhesive. It is particularly preferred to use a moisture-curing adhesive. This is because by introducing water 42 and heating in step P5 in the second step S2 described later, the molding molds 24 and 25 can be filled with water vapor, and the water vapor can be quickly cured.

[0136] The second step S2 includes the following step P5: the polyurethane molding material 21 mixed with the adhesive 22 is put into the molding die 24 and the molding die 25, and water 42 is put into the molding die 24 and heated and pressurized to perform compression molding. The water 42 is sprayed on the polyurethane molding material 21 and the like in a uniformly mixed manner. As an example, the amount of water 42 is between 2 and 10 times that of the adhesive 22. The compression molding of step P5 is heated and compressed for 3 minutes to 20 minutes at a temperature of 120° C. to 160° C. The pressure during compression is between 0.1 MPa and 0.5 MPa.

[0137] <Description of Fourth Embodiment in Method for Producing Polyurethane Molded Article>

[0138] Next, refer to Fig.25 and Fig.26 , a fourth embodiment of the method for manufacturing a polyurethane molded body is described. The adhesive 22 used in the step P3 in the first step S1 is described. The adhesive 22 can use a thermosetting adhesive or a hot melt adhesive. In the step P4 in the first step S1, the substrate 40 is further added to the molding die 24 and the molding die 25. In the second step S2, there is a step P5 for compression molding the polyurethane molding material 21 and the substrate 40 as a whole by heating and pressurizing. The compression molding of the step P5 is performed at a temperature of 120°C to 160°C for a time of between 5 minutes and 30 minutes. The pressure during compression is between 0.1MPa and 0.5MPa. When a wood-based material is used for the substrate 40, in order to suppress the swelling of the substrate 40, a molding method using a high-temperature compression method with a small amount of water in the molding die 24 and the molding die 25 is preferred.

[0139] The polyurethane molded body molded by the method for producing the polyurethane molded body of the fourth embodiment is Figures 6 to 10 The polyurethane molded body 20a to the polyurethane molded body 20e and the reference Fig.12 In step P4, the order of feeding the substrate 40 and the polyurethane molding material 21 is appropriately determined according to the form of the substrate 40.

[0140] For example, in molding Figure 6 In the case of the polyurethane molded body 20a shown, in step P4, the base material 40 is first placed in the mold 24. Then, the polyurethane molding material 21 and the like are placed on the base material 40, and the base material 40 is placed on the upper side of the polyurethane molding material 21 and the like. After step P4, step P5 is performed.

[0141] <Effects of the method for producing a polyurethane molded article>

[0142] The manufacturing method of the polyurethane molding body according to the above description has the following effects. The polyurethane molding body 1, etc. can realize material recycling mainly by using waste materials or leftover materials. Thus, the effect of reducing environmental load is achieved. Even when the present manufacturing method does not include the preparatory process S0, the environmental load can be reduced by using the material processed with waste materials or leftover materials. The main process of manufacturing the polyurethane molding body 1, etc. is the mixing and heating compression of the polyurethane molding material 21 and the adhesive 22. Therefore, the manufacturing method of the polyurethane molding body can realize recycling in the process with few environmental loads. In addition, the manufacturing method of the polyurethane molding body uses the polyurethane molding material 21 processed by the hard polyurethane foam as an example to carry out compression molding, so the thickness and shape corresponding to the purpose can be made.

[0143] In the method for producing a polyurethane molded body, as an example, a shell 11 of a monomer 10 of a rigid polyurethane foam is fragmented to form segments 2, a plurality of adjacent segments 2 are bonded to each other to form a bonded portion 3, and a connecting hole 4 is formed to connect the segments 2 and the bonded portion 3. The segments 2 are at least partially in a meandering state, and at least partially have an end 5 separated from the adjacent segments 2. Therefore, a polyurethane molded body 1 having a large sound absorbing effect can be produced.

[0144] In addition, the method for producing the polyurethane molded body may be a method of crushing the rigid polyurethane foam and passing it through a sieve with a mesh size of 2 mm in advance. In this case, the shell 11 forming the monomer 10 can be more uniformly fragmented to form the fragments 2. Therefore, the polyurethane molded body 1a with a more uniformly improved sound absorption effect can be produced.

[0145] According to the method for producing a polyurethane molded article of the fourth embodiment, in step P4 of the first step S1, the substrate 40 is further introduced into the mold 24. Therefore, the polyurethane molded article 20 can be integrally molded by combining the polyurethane molded layer 9 and the substrate 40. Figures 6 to 10 Therefore, the polyurethane molded body 20 and the sound absorbing material 8c can omit the step of bonding the polyurethane molded body 20 and the sound absorbing material 8c to the base material 40 using an adhesive or the like after molding.

[0146] Example

[0147] <Example of the first embodiment of the polyurethane molded product 1>

[0148] Next, embodiments of the present invention are described. First, embodiments of the polyurethane molded body 1 of the first embodiment are described. Embodiments of the polyurethane molded body 1 of the first embodiment of the present invention are Embodiment 1 and Embodiment 2, and Comparative Examples 1 to 3 are illustrated for comparison. Embodiment 1 is the sound absorbing material 8a of the polyurethane molded body 1a of the present invention, and Embodiment 2 is the sound absorbing material 8b of the polyurethane molded body 1b. Comparative Example 1 is a rigid polyurethane foam before crushing. Comparative Example 2 is rock wool, and Comparative Example 3 is glass wool. It should be noted that the polyurethane molded body 1a of Embodiment 1 is equivalent to Figure 1 and Figure 2 , the polyurethane molded body 1b of Example 2 is equivalent to Figure 3 and Figure 4 , Comparative Example 1 is equivalent to Figure 5 In addition, both the sound absorbing material 8a and the sound absorbing material 8b used for the measurement here have no irregularities on the surface.

[0149] Examples 1 and 2 were molded by the method for manufacturing a molded body described in the first embodiment of the method for manufacturing a polyurethane molded body. In this example, a polymer adhesive having a structure derived from methylene diisocyanate was used, and the adhesive was a moisture-curing adhesive having an isocyanate group at the end. Regarding the conditions during molding, the pressure was 0.2 Pa and compression molding was performed for 5 minutes. The size of the molded product was 200 mm×200 mm×30 mm.

[0150] like Fig. 27 As shown, the size of the polyurethane molding material 21 is the material of Example 1 that has passed through a sieve with a mesh size of 2 mm in advance, and Example 2 is the material that has not passed through a sieve with a mesh size of 2 mm in advance. In Example 2, the size of one side of the polyurethane molding material 21 is approximately 50 mm or less. Regarding the density of Example 1, Example 2, and Comparative Example 1, Example 1, which has the smallest size of the polyurethane molding material 21, has the largest density, and Comparative Example has the smallest density.

[0151] Next, compare the air permeability, such as Fig. 27 As shown, the embodiment 1 and the embodiment 2 are 4.68cm 3 / cm 2 s or more and 6.93cm 3 / cm 2 ·s or less, Comparative Example 1 is 0.23cm 3 / cm 2 ·s. Therefore, Examples 1 and 2 have higher air permeability than Comparative Example 1. The method for measuring air permeability is as described above.

[0152] Next, compare the thermal conductivity, such as Fig. 27As shown in the figure, Example 1 is 0.0334 w / mK, Example 2 is 0.0330 w / mK, and Comparative Example 1 is 0.0375 w / mK. The difference between Example 1 and Example 2 is small, but when Comparative Example 1 is compared with Example 1 and Example 2, a difference with a reproducible degree is confirmed. That is, the polyurethane molded body 1 of the present invention has a lower thermal conductivity than the rigid polyurethane foam before pulverization, and therefore has a high thermal insulation performance.

[0153] Next, refer to Fig.28 The vertical incidence sound absorption rate was compared. The vertical incidence sound absorption rate was measured in accordance with JISA1405-1:2007 "Measurement of sound absorption rate and impedance of acoustic tubes Part 1: Standing wave ratio method". Fig.28 A in FIG. 1 represents Example 1, B represents Example 2, and C represents Comparative Example 1. In the entire frequency region from 0 to 6500 Hz, the normal incidence sound absorption rates of Examples 1 and 2 are higher than that of Comparative Example 1.

[0154] Reference Fig.28 , the frequency ranges in which the vertical incident sound absorption rate of Examples 1 and 2 show characteristic values ​​are described. The sound absorbing material 8a using the polyurethane molded body 1a has a particularly high vertical incident sound absorption rate in the frequency range between 500 Hz and 800 Hz, showing a value exceeding 80%. The sound absorbing material 8b using the polyurethane molded body 1b has a particularly high vertical incident sound absorption rate in the frequency range around 1000 Hz, showing a value exceeding 90%.

[0155] In addition, if Fig.28 As shown, in the frequency range of 2000 Hz to 6500 Hz, the vertical incident sound absorption rate of both Example 1 and Example 2 is significantly higher than that of Comparative Example 1, which is 65% or more. Therefore, although the frequency ranges in which the vertical incident sound absorption rate is significantly high are different between Example 1 and Example 2, the sound absorption effect is great.

[0156] Next, refer to Fig.29 and Fig.30 , which illustrates the vertical incident sound absorption rate at a frequency of 100 Hz to 3100 Hz in Example 1 and Comparative Examples 1 to 3. Fig.29 As shown, the density of Comparative Example 2 is about the same as that of Example 1, and is lower in Comparative Example 3. The thermal conductivity of Comparative Example 2 is lower than that of Example 1, and is about the same as that of Example 3.

[0157] like Fig.30As shown, Example 1 has a significantly higher vertical incident sound absorption rate between 100 Hz and 1000 Hz than Comparative Examples 1 to 3. Generally, rock wool as Comparative Example 2 and glass wool as Comparative Example 3 are used as insulation and sound-absorbing materials for residential walls. Example 1 has a greater sound absorption effect than any of Comparative Examples 1 to 3 in the frequency range below 1000 Hz.

[0158] As described above, in rigid polyurethane of the same material, if the material is crushed to a certain range or is micronized to a certain range, the vertical incident sound absorption rate is higher than that of rigid polyurethane foam, and the sound absorption effect is greater. In addition, if the rigid polyurethane crushed to a certain range is compared with rock wool or glass wool of different materials, the vertical incident sound absorption rate is high in the frequency range of 100 Hz to 1000 Hz. Therefore, the polyurethane molded body 1 molded by the manufacturing method of the polyurethane molded body of the present invention and the sound absorbing material 8 based on the polyurethane molded body 1 have a large sound absorption effect and a heat insulation effect.

[0159] <Example of the second embodiment of the sound absorbing material 8>

[0160] Next, an example of the second embodiment of the sound absorbing material 8 will be described. The example of the second embodiment of the sound absorbing material 8 of the present invention is Example 3. In addition, the comparative example here is Comparative Example 4, but this is Example 1 of the polyurethane molded body 1 of the first embodiment of the present invention. That is, it is a sound absorbing material 8a based on the polyurethane molded body 1a. Example 3 is as described above. Fig.11 As shown in FIG. 1 , the first surface 31a of the sound absorbing material 8c has a convex portion 34. The convex portion 34 is a conical convex portion 34a, the bottom diameter is 10 mm, and the convex portion height h is 10 mm. The thickness L of the sound absorbing material 8c excluding the convex portion 34 is 20 mm. The center-to-center distance between adjacent conical convex portions 34a is 15 mm. In addition, the comparative example 4 is a plate having a thickness L of 30 mm. In addition, the crushed size and density of the embodiment 3 are the same as those of the embodiment 3. Fig. 27 The same as shown in Example 1.

[0161] Fig.31 The vertical incident sound absorption rate of Example 3 and Comparative Example 4 was measured between 500 Hz and 2500 Hz. Fig.28 and Fig.30 The same. In Example 3, the vertical incident sound absorption rate is 65% or more between 1000 Hz and 2500 Hz. Furthermore, the vertical incident sound absorption rate is 70% or more between 1400 Hz and 1800 Hz, which is a higher value than that of Comparative Example 4. It is particularly suitable for general residential use. Therefore, compared with Comparative Example 4 which does not have the concave part 33, the concave part 35, and the convex part 34, Example 3 shows a higher vertical incident sound absorption rate, and thus has a greater sound absorption effect.

Claims

1. A polyurethane molded body comprising: polyurethane segments, a connecting portion where a plurality of adjacent segments are connected to each other, and a communicating hole, wherein at least a portion of the segments is molded in a tortuous state and at least a portion has an end separated from an adjacent segment.

2. The polyurethane molded article according to claim 1, wherein The fragments were previously passed through a sieve with a mesh size of 2 mm.

3. The polyurethane molded article according to claim 1, wherein The fragments were not previously passed through a sieve with a mesh size of 2 mm. 4 . A sound absorbing material comprising the polyurethane molded article according to claim 1 .

5. The sound absorbing material according to claim 4, wherein: The polyurethane molded body has a vertical incident sound absorption rate of 50% or more in a frequency range of 400 Hz to 6500 Hz.

6. The sound absorbing material according to claim 5, wherein: The polyurethane molded body has a vertical incident sound absorption rate of 55% or more in a frequency range of 700 Hz to 6500 Hz.

7. The sound absorbing material according to claim 6, wherein: The polyurethane molded body has a vertical incident sound absorption rate of 60% or more in a frequency range of 2000 Hz to 6500 Hz.

8. The sound absorbing material according to claim 4, wherein: The polyurethane molded body has a surface having concave portions and / or convex portions.

9. The sound absorbing material according to claim 8, wherein: In the frequency range of 1000 Hz to 2500 Hz, the vertical incidence sound absorption rate is over 65%.

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