Description:TECHNICAL FIELD
[001] The embodiments herein generally relate to panels and laminates and more particularly, to acoustic panels and laminates having sound-absorbing and sound-proofing properties.
BACKGROUND
[002] Generally, acoustic panels are used in architectural and interior design for addressing the critical need for noise control and achieving acoustic comfort in various environments. The acoustic panels are designed to absorb unwanted reflections from solid surfaces like walls and ceiling, making the interior space/room acoustically pleasant for its occupants.
[003] Some of the existing economical acoustic panels are mostly mineral wool or gypsum based. Such acoustic panels have design limitations related to aesthetics and often lack versatility in their application in interior design, thereby failing to compliment diverse architectural styles. Gypsum board and mineral wool are not 100 percent recyclable materials and therefore are not entirely environment friendly. Also, most of the times, such acoustic panels/tiles end up in land filling, further affecting the environment.
[004] The conventional acoustic panels also lack versatility in terms of their applications. For example, some acoustic panels are designed solely for wall or ceiling mounting, limiting their use in various architectural configurations such as furniture, lightings, etc. The inability of such acoustic panels to adapt to different installation methods and locations restricts the effectiveness in addressing specific acoustic challenges. Durability is another concern with the acoustic panels. Overtime, traditional fabric wrapped panels may accumulate dust and dirt, making them difficult to clean effectively.
[005] Some acoustic panels such as acoustic ceiling tiles (ACT) have high quality and are aesthetically better than the traditional foam based or fabric wrapped acoustic panels. However, such high quality acoustic panels are highly priced, making such acoustic panels inaccessible for use in budget conscious projects. The cost disparity of such acoustic panels can limit their adoption in applications where noise control is essential, but budgets are constrained. Further, the installation of such acoustic panels may be complex and time consuming, thereby adding significant labor costs to project and delaying timelines. Also, complex installation requirements of such acoustic panels may also necessitate specialized contractors, further increasing project costs.
[006] Several acoustic panels are manufactured using materials that raise environmental concerns. Some mineral wool and foam based panels contain hazardous chemicals or emit volatile organic compounds, contributing to indoor pollution and environmental degradation. In an array of increasing environmental awareness, these drawbacks are significant drawbacks for both designers and users. Also, many existing acoustic panels do not meet stringent sustainability standards, utilizing non-recyclable materials and energy intensive manufacturing processes. This can deter environmentally conscious designers and clients from using these products.
[007] Therefore, there exists a need for acoustic panels which obviates the aforementioned drawbacks.
OBJECTS
[008] The principal object of embodiments herein is to provide acoustic panels having sound absorbing properties and sound proofing properties.
[009] Another object of embodiments herein is to provide acoustic panels which are environment friendly, easy to manufacture and cost effective.
[0010] These and other objects of embodiments herein will be better appreciated and understood when considered in conjunction with following description and accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF DRAWINGS
[0011] The embodiments are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0012] Fig. 1A is a schematic diagram of an acoustic panel, according to a first embodiment as disclosed herein;
[0013] Fig. 1B is another schematic diagram of an acoustic panel, according to the first embodiment as disclosed herein;
[0014] Fig. 2 is a schematic diagram of an acoustic panel, according to a second embodiment of the invention as disclosed herein;
[0015] Fig. 3 is a schematic diagram of an acoustic panel, according to a third embodiment of the invention as disclosed herein;
[0016] Fig. 4 is a schematic diagram of an acoustic panel, according to a fourth embodiment of the invention as disclosed herein; and
[0017] Fig. 5 is a schematic diagram showing area of impedance mismatch in the acoustic panel, according to an embodiment of the invention as disclosed herein.
DETAILED DESCRIPTION
[0018] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0019] The embodiments herein achieve acoustic panels having sound proofing and sound absorbing properties. Further, embodiments herein achieve acoustic panels which are easy to manufacture, environment friendly and cost effective. Referring now to the drawings Figs. 1 through 5, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0020] Fig. 1A and Fig. 1B depict a schematic diagram of an acoustic panel (100), according to a first embodiment as disclosed herein. In the first embodiment, the acoustic panel (100) includes at least two outer layers (102), and at least one inner layer (104) disposed/ sandwiched between the at least two outer layers (102). Each of the at least two outer layers (102) is made of a hard polyethylene terephthalate (PET) felt material and has a first thickness t1. The at least one inner layer (104) is made of a soft PET felt material and has a second thickness t2. For the purpose of this description and ease of understanding, the acoustic panel (100) is considered to comprise an inner layer (104) of soft PET material sandwiched between a top outermost layer (102) and a bottom outermost layer (102) made of hard PET felt material. However, it is within the scope of this invention to have the acoustic panel (100) with a plurality of outer layers and plurality of inner layers arranged in any other order, without otherwise deterring from the intended function of the acoustic panel (100) as can be deduced from the description. In the first embodiment, as shown in Fig. 1A, the inner layer (104) is sandwiched between two outer layers (102) and the layers (102, 104) are joined together to form a laminate. In an embodiment, as shown in Fig, 1B, the acoustic panel (100) includes two inner layers (104) stacked between the top outer layer (102) and the bottom outer layer (102). Further, in the acoustic panel (100), the air flow resistivity of the two outer layers (102) made of hard PET felt material is higher than the air flow resistivity of the inner layer (104) made of soft PET felt material. Furthermore, the first thickness t1 of each of the at least two outer layers (102) ranges from 3 mm to 25 mm. The second thickness t2 of the at least one inner layer (104) ranges from 10 mm to 100 mm. In an embodiment, each of the two outer layers (102) has a thickness of 10 mm and the inner layer (104) has a thickness ranging from 40 mm to 50 mm.
[0021] Fig. 2 is a schematic diagram of the acoustic panel (200), according to a second embodiment. Fig. 3 is a schematic diagram of the acoustic panel (300), according to a third embodiment. In the second embodiment and third embodiment, the acoustic panel (200, 300) includes at least two outer layers (202, 302), at least one inner layer (204, 304), and at least one insulative layer (206, 306). In an embodiment, the third thickness t3 of the insulative layer (206, 306) ranges between 0.5 mm to 25 mm. The insulative layer (206, 306) is made of an insulative material which is configured to act as a sound barrier. For the purpose of this description and ease of understanding, the insulative layer (206, 306) is considered to be made of a material such as but not limited to wood, plastic and metal. However, it is within the scope of this invention to have the insulative layer (206, 306) made of any other material without otherwise deterring from the intended purpose of the insulative layer (206, 306) as can be deduced from the description. As shown in Fig. 2, in the second embodiment, the insulative layer (206) is sandwiched between a bottom outer layer (202) and the inner layer (204). A top outer layer (202) is disposed above the inner layer (204). The top outer layer (202), the inner layer (204), the insulative layer (206), and the bottom outer layer (202) are joined together, forming a laminate. For the purpose of this invention and ease of understanding, the acoustic panel (200) is considered to include two outer layers (202), the inner layer (204) and the insulative layer (206). However, it is within the scope of this invention to have the acoustic panel (200) with a plurality of outer layers, a plurality of inner layers, and a plurality of insulative layers (206) arranged to form a laminate, without otherwise deterring from the intended function of the acoustic panel (200) as can be deduced from the description. In an embodiment, the first thickness t1 of each of the two outer layers (202) is 10 mm and the second thickness t2 of the inner layer (204) is between 40 mm to 50 mm. As shown in Fig. 3, in the third embodiment, the insulative layer (306) is sandwiched between a first inner layer (304) and a second inner layer (304). The top outer layer (302) is disposed above the first inner layer (304) and the bottom outer layer (302) is disposed below the second inner layer (304). The top outer layer (302), the first inner layer (304), the insulative layer (306), the second inner layer (304), and the bottom outer layer (302) are joined together, forming a laminate. For the purpose of this invention and ease of understanding, the acoustic panel (300) is considered to include two outer layers (302), two inner layers (304) and the insulative layer (306). However, it is within the scope of this invention to have the acoustic panel (300) with a plurality of outer layers, a plurality of inner layers, and a plurality of insulative layers arranged to form a laminate, without otherwise deterring from the intended function of the acoustic panel (300) as can be deduced from the description. In an embodiment, each of the two outer layers (302) has the first thickness t1 of 10 mm and each of the first inner layer (304) and the second inner layer (304) has a second thickness t2 between 40mm to 50 mm.
[0022] In the second and the third embodiments, the insulative layer (206, 306) in combination with the at least two outer layers (202, 302) and at least one inner layer (204, 304) is configured to provide acoustic insulation. The acoustic insulation prevents sound from being disseminated in other directions, thereby facilitating reduction of noise in the vicinity.
[0023] Fig. 4 is a schematic diagram of the acoustic panel (400), according to a fourth embodiment. In the fourth embodiment, the acoustic panel (400) includes at least one first outer layer (402) made of hard PET felt material having the first thickness t1, at least one inner layer (404) made of soft PET felt material having the second thickness t2, and at least one second outer layer (406) made of an acoustic fabric having a fourth thickness t4. As shown in Fig. 4, the inner layer (404) is sandwiched between the first outer layer (402) and the second outer layer (406). Each of the first outer layer (402), the inner layer (404), and the second outer layer (406) are joined together, forming a laminate. In an embodiment, the first thickness t1 of the first outer layer (402) is 10 mm, the second thickness t2 of the inner layer (404) is between 25 mm to 50 mm, and the fourth thickness t4 of the acoustic fabric is between 0.5 mm to 2 mm.
[0024] In the first, second, third and fourth embodiments, the GSM of outer layer (102, 202, 302, 402) made of hard PET felt material is between 500 gm/m2 to 3500 gm/m2, and the GSM of inner layer (104, 204, 304, 404) made of soft PET felt material is between 400 gm/m2 to 1600 gm/m2. In the fourth embodiment, the second outer layer (406) made of acoustic fabric has a GSM ranging from 70 gm/m2 to 600 gm/m2. Further, in the first, second, third and fourth embodiments, the outer layer made of hard PET felt material in combination with the inner layer made of soft PET felt material is configured to have a sound absorption coefficient ranging from 0.50 to 0.69. In the fourth embodiment, the second outer layer made of acoustic fabric in combination with the inner layer is configured to have a sound absorption coefficient ranging from 0.30 to 0.65. The optimization of these acoustic multilayers is based upon intrinsic physical parameters like airflow resistivity and sound absorption coefficient. The airflow resistivity is a parameter which provides resistance to sound waves (noise), when it passes through these layers or combination of layers.
[0025] Fig. 5 shows a schematic diagram showing acoustic impedance mismatch in the acoustic panel (100, 200, 300, 400). The outer layer (102, 202, 302, 402) made of hard PET felt material is adapted to have optimized air flow resistivity, wherein the air flow resistivity of the outer layer (102, 202, 302, 402) is in the range of 25 to 75 kNs/m4, which is higher than the air flow resistivity of the inner layer (104, 204, 304, 404) made of soft PET felt material having air flow resistivity in the range of 1 – 10 kNs/m4. Due to the difference in the air flow resistivity of the outer layer (102, 202, 302, 402) and the inner layer (104, 204, 304, 404), an acoustic impedance mismatch occurs at the junction of the outer layer (102, 202, 302, 402) and the inner layer (104, 204, 304, 404). As shown in Fig. 5, the acoustic impedance mismatch occurs in an area (A) near an interface of the outer layer (102, 202, 302, 402) and the inner layer (104, 204, 304, 404). The acoustic impedance mismatch provides higher optimized sound absorption coefficient at mid to high frequencies, making the acoustic panel (100, 200, 300, 400) effective in reducing reverberant noise in the vicinity. Further, by providing outer layers (102, 202, 302, 402, 406) with high air flow resistivity, at a top side and a bottom side of the acoustic panel (100, 200, 300, 400), the acoustic panel (100, 200, 300, 400) is adapted to provide sound absorption from both the top side and the bottom side. Similarly, in the fourth embodiment, wherein the second outer layer (406) is made of acoustic fabric, the acoustic impedance mismatch occurs at the interface of the second outer layer (406) and the inner layer (404), thereby providing similar sound absorption and optimized sound reduction. In an embodiment, the at least one second outer layer (406) made of acoustic fabric has an airflow resistivity ranging from 500 kNs/m4 to 700 kNs/m4. The range of airflow resistivity values of the layers (102, 202, 302, 402, 104, 204, 304, 404, 406) have been measured using ASTM C522.
[0026] The technical advantages of the acoustic panels (100, 200, 300, 400) are as follows. Optimized sound absorption and sound insulation, easy fabrication and installation, cost effective, eco-friendly due to the use of recycled and recyclable PET felt material, optimized acoustic performance in terms of interior noise reduction, 30 – 50% reduction in reverberant sound, provides sound insulation in addition to sound absorption in noisy areas, ease of adaptability in wide range of acoustic applications.
[0027] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications within the spirit and scope of the embodiments as described herein.
, Claims:We claim:
1. An acoustic panel (100, 200, 300) having multiple layers, said acoustic panel (100, 200, 300) comprising:
at least two outer layers (102, 202, 302), each of said at least two outer layers (102, 202, 302) having a first thickness t1;
at least one inner layer (104, 204, 304) disposed between said at least two outer layers (102, 202, 302), said at least one inner layer (104, 204, 304) having a second thickness t2,
wherein,
each of said two outer layers (102, 202, 302) is made of hard PET felt material; and
said at least one inner layer (104, 204, 304) is made of a soft PET felt material having air flow resistivity lower than said hard PET felt material.

2. The acoustic panel (200, 300) as claimed in claim 1, wherein said acoustic panel (200, 300) comprises at least one insulative layer (206, 306) made of an acoustic insulative material, said insulative layer (206, 306) having a third thickness t3.

3. The acoustic panel (200) as claimed in claim 2, wherein said at least one insulative layer (206) is disposed between said at least one inner layer (204) and any one of said at least two outer layers (202).

4. The acoustic panel (300) as claimed in claim 2, wherein said at least one insulative layer (306) is sandwiched between two inner layers (304).

5. The acoustic panel (100, 200, 300) as claimed in claim 1, wherein each of said at least two outer layers (102, 202, 302) and said at least one inner layer (104, 204, 304) are adapted to be joined together using adhesive means, forming a laminate.

6. The acoustic panel (100, 200, 300) as claimed in claim 1, wherein said first thickness t1 of each of said at least two outer layers (102, 202, 302) ranges from 3mm to 25 mm, and said second thickness t2 of said at least one inner layer (104, 204, 304) ranges from 10 mm to 100 mm.

7. The acoustic panel (100, 200, 300) as claimed in claim 1, wherein any one of said at least two outer layers made of hard PET felt material in combination with said at least one inner layer made of soft PET felt material is configured to have a sound absorption coefficient ranging from 0.50 to 0.69.

8. The acoustic panel (200, 300) as claimed in claim 2, wherein said at least one insulative layer (206, 306) is made of a material comprising any one of wood, plastic and metal, and wherein said third thickness t3 of said at least one insulative layer (206, 306) ranges from 0.5 mm to 25 mm.

9. The acoustic panel (100, 200, 300) as claimed in claim 6, wherein each of said at least two outer layers (102, 202, 302) has a GSM ranging from 500 gm/m2 to 3500 gm/m2, and said at least one inner layer (104, 204, 304) has GSM ranging from 400 gm/m2 to 1600 gm/m2.

10. The acoustic panel (100, 200, 300) as claimed in claim 1, wherein each of said at least two outer layers (102, 202, 302, 402) made of hard PET felt material has an air flow resistivity in a range of 25 kNs/m4 to 75 kNs/m4, and said at least one inner layer (104, 204, 304, 404) made of soft PET felt material has air flow resistivity in a range of 1 kNs/m4 to10 kNs/m4.

11. An acoustic panel (400) having multiple layers, said acoustic panel (400) comprising:
at least one first outer layer (402) having a first thickness t1;
at least one second outer layer (406) having a fourth thickness t4; and
at least one inner layer (404) disposed between said at least one first outer layer (402) and said at least one second outer layer (406), said at least one inner layer (404) having a second thickness t2,
wherein,
said at least one first outer layer (402) is made of a hard PET felt material;
said at least one second outer layer (406) is made of acoustic fabric material; and
said at least one inner layer (404) is made of a soft PET felt material having air flow resistivity lower than said hard PET felt material and acoustic fabric material.

12. The acoustic panel (400) as claimed in claim 11, wherein said first thickness t1 of said at least one outer layer (402) ranges from 3 mm to 25 mm, said second thickness t2 of said at least one inner layer (404) ranges from 10 mm to 100 mm, and said fourth thickness t4 of said at least one second outer layer (406) ranges from 0.5 mm to 2 mm.

13. The acoustic panel (400) as claimed in claim 12, wherein said at least one first outer layer (402) has a GSM ranging from 500 gm/m2 to 3500, gm/m2 said at least one inner layer (404) has a GSM ranging from 400 gm/m2 to 1600 gm/m2, and said at least one second outer layer (406) has a GSM ranging from 70 gm/m2 to 600 gm/m2

14. The acoustic panel (400) as claimed in claim 11, wherein each of said at least one first outer layer (402), at least one second outer layer (406), and at least one inner layer (404) are joined together to form a laminate.

15. The acoustic panel (400) as claimed in claim 11, wherein said at least one first outer layer (402) made of hard PET felt material in combination with said at least one inner layer (404) made of soft PET felt material is configured to have a sound absorption coefficient ranging from 0.50 to 0.69, and said at least one second outer layer (406) in combination with said at least one inner layer (404) is configured to have a sound absorption coefficient ranging from 0.30 to 0.65.

16. The acoustic panel (400) as claimed in claim 11, wherein said at least one first outer layer (402) has an air flow resistivity in a range of 25 kNs/m4 to 75 kNs/m4, said at least one inner layer (404) made of soft PET felt material has air flow resistivity in a range of 1 kNs/m4 to10 kNs/m4, and said at least one second outer layer (406) made of acoustic fabric has air flow resistivity ranging from 500 kNs/m4 to 700 kNs/m4.