AU782550B2

AU782550B2 - A pinnable acoustic panel

Info

Publication number: AU782550B2
Application number: AU48754/00A
Authority: AU
Inventors: Marek Kierzskowi; Coates Michael
Original assignee: INC Corp Pty Ltd
Current assignee: Inc Corp Pty Ltd
Priority date: 1999-07-21
Filing date: 2000-07-21
Publication date: 2005-08-11
Anticipated expiration: 2020-07-21
Also published as: AU4875400A

Description

Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A COMPLETE PATENT

(ORIGINAL)

Name of Applicant(s): I.N.C. Corporation Pty Ltd, A.B.N. 74 005 302 250, of 22 Cleeland Road, Oakleigh South 3167, Australia Address for Service: DAVIES COLLISON CAVE, Patent Attorneys, of 1 Little Collins Street, Melbourne, Victoria 3000, Australia Invention Title: "A pinnable acoustic panel" Associated Provisional Application No.: PQ1748/99 The following statement is a full description of this invention, including the best method of performing it known to us.

Q:\OPER\LKAU317845 patenidoc 21nl/oo PO4'ERKAU2317845 ap.doc.21M7mO -2- A PINNABLE ACOUSTIC PANEL This invention relates to acoustic panels of the kind used for lining of walls, dividers and the like in buildings. More particularly it relates to pinnable acoustic panels which in addition to providing for acoustic absorption must also be capable of receiving and securely holding a pin of the type used for temporarily attaching articles to the panel.

Panels of this type are used in a variety of environments including educational institutions and offices. The panels are also required to be decorative and therefore most commonly have an outer layer of pattern fabric of some type. For the panel to be "pinnable" it must receive and securely hold a standard pin. A standard pin may have different head forms but has a shank approximately long and 1mm in diameter. In order to achieve the necessary pin retention characteristics known panels of this type have included a layer of closed cell foam which provides the firmer dense medium for receipt of the pin. In order to obtain the necessary acoustic properties a layer of open cell foam is adhered to the closed cell foam and a further membrane is adhered to the open cell foam layer.

The present invention seeks to avoid th use of a closed cell foam layer in a pinnable acoustic panel whilst providing a panel with superior acoustic qualities and the required pin retention characteristics.

,.i Accordingly, in one aspect this invention provides a pinnable acoustic panel including a layer of open cell foam substantially forming the thickness of a panel and a thin porous membrane adhered to the foam provide an air flow resistance of between 500 and 2000 Rayls, the compressibility of the panel being such that the penetration of the membrane by a standard pin causes minimal compression of the panel.

Preferably, a layer of fabric facing is adhered to the thin porous membrane.

PAOPERUJA'.Z317145 sCI.2lD271 -3- In a preferred embodiment the porous membrane is a polyester membrane. The membrane preferably has a density of about 250 gsm and a thickness of between 0.3 and 0.7mm. More preferably the thickness is about The open cell foam has a preferred density of 29kg/m 3 and an indentation force deflection of 400 Newtons, when tested to Australian standard AS 2281, which is a measure of the compressibility of the foam. The foam is preferably a polyether foam and is preferably about 10mm thick, however there is no theoretical limitation to the thickness. The preferred thickness is practical for actual usage.

In the preferred form of the invention the flow resistance of the panel is between ~600 and 800 Rayls.

The open cell foam is preferably laminated with the thin porous membrane using a 5 permeable thermoplastic adhesive. The fabric facing is preferably laminated onto the membrane using a discontinuous layer of thermoplastic adhesive powder. In the preferred form, a one component heat reactive curable polyurethane melt adhesive.

20 In some embodiments the fabric cover d1i also be chosen to receive a fastener such as VELCRO.

In the strongly preferred form of the invention the thin porous membrane and the facing fabric are 100% polyester so that the product complies with Australian Standard Early Fire Hazard Test AS1530.3.

The force required for insertion of a standard pin into the panel is about 4.5N or greater and in tests this results in a material deflection at the surface of less than about POPER'lKAU317S45 clp.doc-217/00 -4- The use of an open cell foam making up substantially the thickness of the panel allows the whole of that thickness to be used as an acoustic space. That is, the flow resistance is substantially determined by the thin membrane adhered to the foam and the foam region serves as the acoustic damping space.

In a second aspect this invention provides a method of forming a thin acoustic panel including the steps of laminating a layer of open cell foam substantially forming the thickness of the panel to a thin porous membrane to provide an air flow resistance of between 500 and 2000 Rayls, the compressibility of the panel being such that penetration of the membrane by a standard pin causes minimal compression of the panel.

o* The invention will now be described, by way of a non limiting example with reference to the accompanying drawing which is a plot of normal incidence sound 15 absorption and coefficient against acoustic frequency for a number of pinnable acoustic panels made in accordance with the invention.

Example A pinnable acoustic panel was formed by laminating a 10mm thick polyether open cell foam grade U29/400 to AS 2281, to 0.5mm thick 250 gsm polyester membrane using a polyester adhesive film. A polyester fabric facing was laminated onto the membrane surface using a thermoplastic adhesive powder.

The flow resistance of the panel thus formed was about 800 Rayls.

The panels were subject to sound absorption tests using a standard impedance tube testing to ASTM E 1050-9/ISO/CD 10534-2. The minimum and typical sound absorption coefficient are shown in Figure 1. In addition, the panels have pin retention characteristics equal to or superior to known pinnable acoustic panels.

The panels also possess at least same degree of flexibility as known panels so they are suitable for transportation in roll form.

P:OPER\LKAU231745 p doc-21Ix7/0 Testing of the panels found that they meet the Australian standard early fire hazard test AS 1530.3 returning indices better or equal to: ignitability spread of flame 9 heat evolved 4 smoke developed 6 The foregoing describes only one embodiment of the invention and modifications can be made without departing from the scope of the invention.

.9 o* 0 0 o o

Claims

1. A pinnable acoustic panel including a layer of open cell foam substantially forming the thickness of a panel and a thin porous membrane adhered to the foam to provide an air flow resistance of between 500 and 2000 Rayls, the compressibility of the panel being such that the penetration of the membrane by a standard pin causes minimal compression of the panel.

2. A pinnable acoustic panel as claimed in claim 1 wherein a layer of fabric facing is adhered to the thin porous membrane.

3. A pinnable acoustic panel as claimed in claim 1 or claim 2 wherein the porous membrane is a polyester membrane.

4. A pinnable acoustic panel as claimed in any one of claims 1 to 3 wherein said membrane has a density of about 250 gsm.

A pinnable acoustic panel as claimed in any one of claims 1 to 3 wherein 15 said membrane has a thickness of between 0.3 and 0.7mm.

6. A pinnable acoustic panel as claimed in claim 4 or claim 5 wherein said membrane has a thickness of about

7. A pinnable acoustic panel as claimed in any one of claims 1 to 6 wherein said open cell foam has a density of about 29kg/m 3 and an indentation 20 force deflection of 400 Newtons,, When tested to Australian standard AS

2281.

8. A pinnable acoustic panel as claimed in claim 7 wherein said open cell foam is a polyether foam about 10mm thick.

9. A pinnable acoustic panel as claimed in any one of claims 1 to 8 wherein the flow resistance of the panel is between 600 and 800 Rayls. A pinnable acoustic panel as claimed in any one of claims 1 to 9 wherein said open cell foam is laminated to the thin porous membrane with a permeable thermoplastic adhesive. 11. A pinnable acoustic panel as claimed in claim 2 wherein the fabric facing is laminated to the membrane using a discontinuous layer of thermoplastic adhesive powder. P-%OR\LUCU31724S c.dp-2Id -7- 12. A pinnable acoustic panel as claimed in claim 2 or claim 11 wherein the thin porous membrane and the facing fabric are 100% polyester. 13. A method of forming a thin acoustic panel including the steps of laminating a layer of open cell foam substantially forming the thickness of the panel to a thin porous membrane to provide an air flow resistance of between 500 and 2000 Rayls, the compressibility of the panel being such that penetration of the membrane by a standard pin causes minimal compression of the panel. 14. A method of forming a thin acoustic panel as claimed in claim 13 further eo 10 including the step of adhering a layer of fabric facing to the thin porous e layer. A method of forming a thin acoustic panel as claimed in claim 13 or claim 14 further including laminating the open cell foam to the thin porous membrane with a permeable thermoplastic adhesive. 15 16. A method of forming a thin acoustic panel as claimed in claim 14 further including laminating the fabric facing to the membrane using a discontinuous layer of adhesive powder. eoo° o A method of forming a thin acoustic panel as claimed in any one of claims 13 to 16 wherein the porous membrane is a polyester membrane. 18. A method of forming a thin acoustic'panel as claimed in any one of claims 13 to 17 wherein said membrane has a density of about 250 gsm. 19. A method of forming a thin acoustic panel as claimed in any one of claims 13 to 18 wherein said membrane has a thickness of between 0.3 and 0.7mm. 20. A method of forming a thin acoustic panel as claimed in claim 19 wherein said membrane has a thickness of about 21. A method of forming a thin acoustic panel as claimed in any one of claims 13 to 20 wherein said open cell foam has a density of about 29kg/m 3 and an indentation force deflection of 400 Newtons, when tested to Australian standard AS 2281. P AOPERU"3A'2173 cp.doE2IM7MV -8- 22. A method of forming a thin acoustic panel as claimed in claim 21 wherein said open cell foam is a polyether foam about 10mm thick. 23. A method of forming a thin acoustic panel as claimed in any one of claims 13 to 22 wherein the flow resistance of the panel is between 600 and 800 Rayls. DATED this 21st day of July, 2000.

10 I.N.C. Corporation Pty Ltd DAVIES COLLISON CAVE Patent Attorneys for the Applicant