Sound insulation sheet, manufacturing method thereof, and sound insulation structure
To provide a sound insulation sheet member which is excellent in sound insulation performance in a low frequency band and which has a compact configuration. A sound insulation sheet member 1 including a substrate 2 and a concavo-convex structure 3 placed on at least one surface of the substrate 2 , in which the concavo-convex structure 3 is provided by repeatedly arranging a plurality of units each defined as a concavo-convex unit shape 4 including a linear convex portion 5 , in one direction at substantially constant intervals on the surface of the substrate 2.
1. A sound insulation sheet comprising a concavo-convex structure on at least one surface of a sheet-shaped substrate, wherein
the concavo-convex structure comprises a plurality of rows of continuous convex protrusions from a sheet surface of the substrate separated by rows of concave portions,
the rows of continuous convex protrusions are linearly arranged in one direction with respect to one another and do not overlap,
each row of continuous convex protrusion has a length in a longitudinal direction and a width in a transverse direction wherein a ratio of a maximum length in the longitudinal direction to the width in the transverse direction is 35 or more,
a shape of a transverse section of the rows of continuous convex protrusions is selected from the group consisting of a square shape, a rectangular shape, a trapezoidal shape, a semicircular shape and an oval shape, and
the substrate has a Young's modulus of 1 GPa or more and 10 GPa or less.
2. The sound insulation sheet according to claim 1 , wherein the substrate has a thickness (d) of 30 μm or more and 500 μm or less.
3. The sound insulation sheet according to claim 1 , wherein the rows of continuous convex protrusions have a height (t) of 0.5 mm or more and 10 mm or less.
4. The sound insulation sheet according to claim 1 , wherein
the concavo-convex structure is within ranges determined by expressions (I) and (II):
0.1≤ w 1max× t×sg/w 2≤10 Expression (I)
5≤ w 1max× t≤ 50 Expression (II)
wherein a maximum width of a transverse section of a row of continuous convex protrusion is w1max (mm), a height of a row of continuous convex protrusion is t (mm), a width of a concave row is w2 (mm) and a specific gravity of the row of continuous convex protrusion is sg.
5. The sound insulation sheet according to claim 4 , wherein a transverse section of the row of continuous convex protrusion has a maximum width (w1max) of 0.5 mm or more and 10 mm or less.
6. The sound insulation sheet according to claim 4 , wherein the concave row has a width (w2) of 3 mm or more and 100 mm or less.
7. A method for manufacturing the sound insulation sheet according to claim 1 , comprising
flowing a photo-curable resin into a plurality of continuous concave grooves provided on a surface of a mold,
overlapping with the mold, a substrate sheet through which a specified ray of light penetrates, the sheet being placed with facing the concave grooves into which the photo-curable resin flows, and subjecting the resultant overlapping arrangement to pressure bonding,
irradiating with the specified ray of light through the substrate sheet to thereby cure the photo-curable resin in the concave grooves and fix the photo-curable resin to the substrate sheet, and
releasing the substrate sheet from the mold.
8. The method for manufacturing a sound insulation sheet according to claim 7 , wherein the mold is a roll-shaped mold obtained by providing on its periphery, the plurality of concave grooves each extending along a circumferential direction.
9. A sound insulation structure comprising the sound insulation sheet according to claim 1 , and a support which supports a surface of the substrate.
10. A sound insulation structure comprising the sound insulation sheet according to claim 1 and a plate material provided opposite to the sound insulation sheet, wherein a space section is provided between the sound insulation sheet and the plate material.
11. A sound insulation structure according to claim 10 . comprising a retention unit provided between the sound insulation sheet and the plate material, wherein the space section is a space section formed together with the support.
12. The sound insulation structure according to claim 11 , wherein the space section provided between the sound insulation sheet and the plate material is a sealed space closed by the sound insulation sheet, the plate material and the retention unit.
13. The sound insulation structure according to claim 11 , wherein the retention unit is in a form of a frame.
14. The sound insulation structure according to claim 10 , wherein a placement interval (g) between the sound insulation sheet and the plate material in the space section is 0.1 mm or more and 50 mm or less.
15. The sound insulation structure according to claim 10 , wherein a sound absorbing material is packed in the space section.
16. The sound insulation structure according to claim 15 , wherein the sound absorbing material is a non-woven fabric.
17. The sound insulation structure according to claim 10 , wherein the plate material has a surface density of 1 kg/m 2 or more and 20 kg/m 2 or less.
18. A sound insulation structure having a configuration comprising:
a sound insulation sheet having a concavo-convex structure according to claim 1 on at least one surface of a substrate,
a plate material provided opposite to the sound insulation sheet, and
a retention unit provided between the sound insulation sheet and the plate material, wherein
a space section formed by the sound insulation sheet, the plate material and the retention unit is provided between the sound insulation sheet and the plate material.
19. The sound insulation structure according to claim 18 , wherein the space section provided between the sound insulation sheet and the plate material is a sealed space closed by the sound insulation sheet, the plate material and the retention unit.
20. The sound insulation structure according to claim 18 , wherein the retention unit is in a form of a frame.
21. The sound insulation structure according to claim 18 , wherein a placement interval (g) between the sound insulation sheet and the plate material in the space section is 0.1 mm or more and 50 mm or less.
22. The sound insulation structure according to claim 18 , wherein a sound absorbing material is packed in the space section.
23. The sound insulation structure according to claim 22 , wherein the sound absorbing material is a non-woven fabric.
24. The sound insulation structure according to claim 18 , wherein the concavo-convex structure is within ranges determined by expressions (I) and (II):
0.1≤ w 1max× t×sg/w 2≤10 Expression (I)
5≤ w 1max× t≤ 50 Expression (II)
wherein a maximum width of a transverse section of a row of continuous convex protrusion is w1max (mm), a height of a row of continuous convex protrusion is t (mm), a width of the a concave row is w2 (mm) and a specific gravity of the row of continuous convex protrusion is sg.
25. The sound insulation structure according to claim 18 , wherein a proportion of an area of the concavo-convex structure in an area of one surface of the substrate is 5% or more and 80% or less.
26. The sound insulation structure according to claim 18 , wherein the concavo-convex structure of the sound insulation sheet comprises at least one selected from the group consisting of a thermosetting or photo-curable elastomer, a thermoplastic elastomer, a thermosetting or photo-curable resin and a thermoplastic resin.
27. The sound insulation structure according to claim 18 , wherein the substrate of the sound insulation sheet has a Young's modulus of 1 GPa or more.
28. The sound insulation structure according to claim 18 , wherein the plate material has a surface density of 1 kg/m 2 or more and 20 kg/m 2 or less.