U.S. patent application number 11/973314 was filed with the patent office on 2008-04-17 for noise-attenuating laminate composite wallboard panel and methods for manufacturing same.
Invention is credited to Ronald C. Averill.
Application Number | 20080086957 11/973314 |
Document ID | / |
Family ID | 39301903 |
Filed Date | 2008-04-17 |
United States Patent
Application |
20080086957 |
Kind Code |
A1 |
Averill; Ronald C. |
April 17, 2008 |
Noise-attenuating laminate composite wallboard panel and methods
for manufacturing same
Abstract
A laminate composite wallboard panel is disclosed having
multiple layers whose cross sections may contain internal and
external non-uniformities and whose surfaces may be rough and
non-uniform. The wallboard panel is similar in size and weight to a
standard gypsum panel and can be handled and installed in a manner
similar to such a panel. The wallboard panel also provides high
degrees of noise attenuation, thermal insulation, fire resistance,
shear strength, mold resistance and moisture resistance.
Inventors: |
Averill; Ronald C.; (East
Lansing, MI) |
Correspondence
Address: |
ROPERS , MAJESKI , KOHN & BENLTEY
1001 MARSHALL STREET , SUITE 300
REDWOOD CITY
CA
94063
US
|
Family ID: |
39301903 |
Appl. No.: |
11/973314 |
Filed: |
October 4, 2007 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60849564 |
Oct 4, 2006 |
|
|
|
Current U.S.
Class: |
52/144 ;
52/745.19 |
Current CPC
Class: |
B32B 13/08 20130101;
E04B 2001/8461 20130101; B32B 29/06 20130101; E04B 1/86
20130101 |
Class at
Publication: |
052/144 ;
052/745.19 |
International
Class: |
E04B 1/82 20060101
E04B001/82; E04B 1/92 20060101 E04B001/92 |
Claims
1. A laminar, sound-absorbing structure for constructing walls and
ceilings, comprising: a plurality of layers wherein one or more of
the layers has internal and/or external non-uniformities and/or
surfaces that are rough and/or non-uniform.
2. The laminar structure of claim 1 wherein said plurality of
layers consists of five layers, comprising: a first layer made of a
selected material; which is contact with a second layer made of a
viscoelastic adhesive; which is in contact with a third layer made
of a selected material; which is contact with a fourth layer made
of a viscoelastic adhesive; and which is in contact with a fifth
layer made of a selected material.
3. The laminar structure of claim 2 wherein the first layer
comprises a gypsum panel.
4. The laminar structure of claim 2 wherein the third layer
comprises a sheet of absorbent paper.
5. The laminar structure of claim 2 wherein the fifth layer
comprises an MgO panel.
6. The laminar structure of claim 3 wherein the third layer
comprises a sheet of absorbent paper.
7. The laminar structure of claim 6 wherein the fifth layer
comprises an MgO panel.
8. The laminar structure of claim 6 wherein the fifth layer
comprises a gypsum panel.
9. The laminar structure of claim 5 wherein the third layer
comprises a sheet of absorbent paper.
10. The laminar structure of claim 9 wherein the first layer
comprises an MgO panel.
11. The laminar structure of claim 3 wherein the fifth layer
comprises a gypsum panel.
12. The laminar structure of claim 3 wherein the fifth layer
comprises an MgO panel.
13. The laminar structure of claim 5 wherein the first layer
comprises an MgO panel.
14. The laminar structure of claim 1 wherein said plurality of
layers consists of three layers, comprising: a first layer made of
a selected material; which is contact with a second layer made of a
viscoelastic adhesive; and which is in contact with a third layer
made of a selected material.
15. The laminar structure of claim 14 wherein the first layer
comprises a gypsum panel.
16. The laminar structure of claim 14 wherein the first layer
comprises an MgO panel.
17. The laminar structure of claim 15 wherein the third layer
comprises a gypsum panel.
18. The laminar structure of claim 15 wherein the third layer
comprises an MgO panel.
19. The laminar structure of claim 16 wherein the third layer
comprises an MgO panel.
20. The laminar structure in either of claims 1 and 14 comprising
three or more layers where: at least one layer has internal and/or
external non-uniformities and/or surfaces that are rough and/or
non-uniform; and at least one layer is made of a viscoelastic
adhesive.
21. The laminar structure in any of claims 1, 14, and 20 wherein
the first layer is selected from a group consisting of gypsum
panels, MgO panels, wood, plywood, metal, fiber glass, polymers,
fire retardant panels, and high-density mat materials wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
22. The laminar structure in any of claims 1, 14, and 20 wherein
the third layer is selected from a group consisting of paper,
gypsum panels, MgO panels, metal, wood, ceramic, and polymers
wherein said materials may be cellular or foamed and have may have
internal and/or external non-uniformities and/or surfaces that are
rough and/or non-uniform.
23. The laminar structure in either of claims 1 and 2 comprising
five or more layers where: at least one layer has internal and/or
external non-uniformities and/or surfaces that are rough and/or
non-uniform; and at least one layer is made of a viscoelastic
adhesive.
24. The laminar structure in any of claims 1, 2, and 23 wherein the
first layer is selected from a group consisting of gypsum panels,
MgO panels, wood, plywood, metal, fiber glass, polymers, fire
retardant panels, and high-density mat materials wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
25. The laminar structure in any of claims 1, 2, and 23 wherein the
third layer is selected from a group consisting of paper, gypsum
panels, MgO panels, metal, wood, ceramic, and polymers wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
26. The laminar structure in any of claims 1, 2, and 23 wherein the
fifth layer is selected from a group consisting of gypsum panels,
MgO panels, wood, plywood, metal, fiber glass, polymers, fire
retardant panels, and high-density mat materials wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
27. The laminar structure of claim 1 comprising seven or more
layers where: at least one layer has internal and/or external
non-uniformities and/or surfaces that are rough and/or non-uniform;
and at least one layer is made of a viscoelastic adhesive.
28. The laminar structure in either of claims 1 and 27 wherein the
first layer is selected from a group consisting of gypsum panels,
MgO panels, wood, plywood, metal, fiber glass, polymers, fire
retardant panels, and high-density mat materials wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
29. The laminar structure in either of claims 1 and 27 wherein the
third layer is selected from a group consisting of paper, gypsum
panels, MgO panels, metal, wood, ceramic, and polymers wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
30. The laminar structure in either of claims 1 and 27 wherein the
fifth layer is selected from a group consisting of gypsum panels,
MgO panels, wood, plywood, metal, fiber glass, polymers, fire
retardant panels, and high-density mat materials wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
31. The laminar structure in either of claims 1 and 27 wherein the
seventh layer is selected from a group consisting of gypsum panels,
MgO panels, wood, plywood, metal, fiber glass, polymers, fire
retardant panels, and high-density mat materials wherein said
materials may be cellular or foamed and have may have internal
and/or external non-uniformities and/or surfaces that are rough
and/or non-uniform.
32. The method of forming a laminar, sound-absorbing structure for
constructing walls and ceilings which comprises: providing a layer
of first material having two surfaces; placing a layer of
viscoelastic adhesive onto one surface of said layer of first
material; placing a layer of second material onto said layer of
viscoelastic adhesive; applying selected amounts of pressure on
selected portions of the layer of second material for selected
amounts of time; and heating/cooling said layers of laminar
structure at selected temperatures for selected amounts of
time.
33. The laminar structure of claim 32 wherein the layer of first
material is selected from a group consisting of gypsum panels, MgO
panels, wood, plywood, metal, fiber glass, polymers, fire retardant
panels, and high-density mat materials wherein said materials may
be cellular or foamed and have may have internal and/or external
non-uniformities and/or surfaces that are rough and/or
non-uniform.
34. The laminar structure of claim 32 wherein the layer of third
material is selected from a group consisting of gypsum panels, MgO
panels, wood, plywood, metal, fiber glass, polymers, fire retardant
panels, and high-density mat materials wherein said materials may
be cellular or foamed and have may have internal and/or external
non-uniformities and/or surfaces that are rough and/or
non-uniform.
35. The method of forming a laminar, sound-absorbing structure for
constructing walls and ceilings which comprises: providing a layer
of first material having two surfaces; placing a layer of
viscoelastic adhesive onto one surface of said layer of first
material; placing a layer of second material onto said layer of
viscoelastic adhesive; placing a layer of viscoelastic adhesive
onto the exposed surface of said layer of second material; placing
a layer of third material onto said layer of viscoelastic adhesive
affixed to said layer of second material; applying selected amounts
of pressure on selected portions of the layer of third material for
selected amounts of time; and heating/cooling said layers of
laminar structure at selected temperatures for selected amounts of
time.
36. The laminar structure of claim 35 wherein the layer of first
material is selected from a group consisting of gypsum panels, MgO
panels, wood, plywood, metal, fiber glass, polymers, fire retardant
panels, and high-density mat materials wherein said materials may
be cellular or foamed and have may have internal and/or external
non-uniformities and/or surfaces that are rough and/or
non-uniform.
37. The laminar structure of claim 35 wherein the layer of second
material is selected from a group consisting of gypsum panels, MgO
panels, wood, plywood, metal, fiber glass, polymers, fire retardant
panels, and high-density mat materials wherein said materials may
be cellular or foamed and have may have internal and/or external
non-uniformities and/or surfaces that are rough and/or
non-uniform.
38. The laminar structure of claim 35 wherein the layer of third
material is selected from a group consisting of gypsum panels, MgO
panels, wood, plywood, metal, fiber glass, polymers, fire retardant
panels, and high-density mat materials wherein said materials may
be cellular or foamed and have may have internal and/or external
non-uniformities and/or surfaces that are rough and/or non-uniform.
Description
FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT STATEMENT
[0001] This invention was not developed in conjunction with any
Federally sponsored contract.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to building materials and,
more particularly, to a laminate composite panel for use in
residential and commercial buildings.
[0004] 2. Prior Art
[0005] Gypsum-based panels were first used to construct the
interior walls of buildings nearly 100 years ago. Since then, the
standard design of such panels has consisted of a gypsum core
sandwiched between two layers of paper. Commercially available
panels generally have gypsum cores ranging in thickness from 1/4''
to 3/4'', while the panels' large surfaces typically have widths of
48'' or 54'' and lengths ranging from 8' to 12' in one-foot
increments. Within the construction trade, gypsum-based panels are
interchangeably referred to as "drywall," "wallboard," "gypsum
wallboard," and "gypsum panels," while the name "Sheetrock.RTM." is
a trademark of the U.S. Gypsum Company and is used to describe
gypsum panels sold by that firm.
[0006] Since at least the 1950s, gypsum panels have been
incorporated into laminate structures in attempts to address
specific requirements of the construction industry, such as
increased strength, fire resistance, thermal insulation, moisture
resistance, mold resistance, and noise attenuation.
[0007] U.S. Pat. No. 6,901,713, for example, discloses a wallboard
panel consisting of a standard gypsum panel bonded to a thin
aluminum sheet. The principal object of this patent is to increase
the shear strength, thermal insulation, and fire resistance over
that provided by a standard gypsum panel.
[0008] U.S. Pat. Nos. 3,106,503 and 6,711,872 disclose paper-based
honeycomb structures bonded on one or both sides to standard gypsum
panels. These inventions provide increased shear strength and fire
resistance.
[0009] U.S. Pat. Appl. No. 2005/0262799 discloses a gypsum panel
onto which has been laminated a fiber-cement composition, thereby
providing an increase in the composite structure's ability to
resist physical abuse from objects (e.g., chairs, tables, toys)
that come into contact with the panel.
[0010] U.S. Pat. No. 5,768,841 discloses a standard gypsum panel
onto which is glued a metal sheet having a thickness between
0.015'' and 0.060''. This invention improves upon the in-plane and
shear strengths provided by the standard gypsum panel.
[0011] U.S. Pat. No. 5,573,829 discloses a standard gypsum panel
that is laminated with an aluminum-backed wood veneer. This
invention provides a surface that may be debossed with decorative
designs.
[0012] Over the last 10 years, the construction industry has placed
increased importance on the development and application of
materials that achieve high levels of noise attenuation. The
excessive transmission of noise through walls, ceilings, floors,
and doors is a major complaint of the occupants of virtually all
buildings, including single-family homes, condominiums, apartments,
office buildings, health care facilities, hotels, and schools.
These complaints arise not only from noise generated by the
occupants of neighboring units, but also from noise produced by
exterior noise sources, such as roads, railways, and airports. In
recent years, government agencies have set stringent
noise-attenuation standards that govern the construction of both
new and renovated residential and commercial buildings.
[0013] There are three basic approaches to enhance noise
attenuation in walls and related structures. The first is the use
of high-density materials and/or thick-walled construction to
increase the mass of the wall. This approach is effective,
especially for low frequency noise, but it is very expensive and
decreases the amount of living space. The second approach is to
decouple all or part of a wall panel from its support studs in
order to reduce the mechanical transmission of noise energy from
the panel to the studs. This decoupling approach can be relatively
effective in controlled circumstances, but it is difficult to
implement and is easily defeated post-installation by, for example,
hanging fixtures on the wall. The third approach is to use
energy-absorbing materials to damp out mechanical vibrations in the
wall. Polymers, foams, and matted materials are commonly used for
this purpose, but the use of any single material is often effective
primarily over only a relatively narrow frequency range. More
recently, however, noise-attenuating wallboards based upon
composite laminates have been developed to dampen sounds over a
broader frequency range.
[0014] ASTM International ("ASTM"; formerly the American Society
for Testing Materials) has set forth a standard scale--the Sound
Transmission Class (STC)--to rate the noise attenuation provided by
various partition assemblies. The STC is a single-figure rating
system that measures the acoustical performance of a wall partition
assembly under typical conditions involving dwellings or offices.
The higher the STC rating, the better the partition
performance.
[0015] In determining the STC rating of a wall partition, two (or
more) wallboard panels are used to construct a wall assembly
separating the test area into two regions: the "test chamber" and
the "receiving room." Electronic equipment located in the test
chamber is then used to generate sounds at standard frequencies and
volumes, while additional equipment in the receiving room measures
the sound that passes through the partition into the receiving
room. The sound transmission loss between the test chamber and the
receiving room is measured in decibels (dB) and plotted as a
function of frequency in 1/3-octave bands from 125 Hz to 4,000 Hz.
From the data, an STC rating is determined. The ASTM test standard
for evaluating a partition assembly is ASTM E90-04, "Standard Test
Method for Laboratory Measurement of Airborne Sound Transmission
Loss of Building Partitions and Elements," while the ASTM standard
for determining the STC rating is ASTM E413-04, "Classification for
Rating Sound Insulation."
[0016] The prior art includes at least two wallboard inventions
that achieve noise attenuation via gypsum-based composite
laminates.
[0017] U.S. Pat. No. 6,758,305 discloses a two-layer laminate
having a structural first face consisting of a gypsum panel (or
plywood sheet) and a second face constructed from one or more of a
variety of materials, such as recycled newsprint, perlite,
fiberglass, EPDM rubber, or latex. The invention's
noise-attenuation properties predominately arise from the device's
second layer. This patent discloses that an STC rating of
approximately 50 may be achieved through the invention.
[0018] U.S. Pat. Appl. No. 2005/0050846 discloses a multi-layer
laminate having, as its wallboard embodiment, a 0.013'' core of
galvanized steel sandwiched between layers of viscoelastic glue,
each of which is attached to a gypsum panel. The invention achieves
its sound-attenuation properties from the principle of "constrained
layer damping," which arises from the presence of the steel sheet
that helps to constrain the laminate's layers of viscoelastic glue.
Because of the steel sheet, however, a 4'.times.8' panel of this
embodiment weighs 108 pounds, whereas a single-sheet gypsum panel
of equivalent thickness (i.e., 5/8'') weighs as little as 67
pounds. Moreover, the presence of the steel sheet in the invention
requires that a power tool be used to cut panels. In contrast,
standard gypsum panels have, for more than 90 years, been cut by a
utility knife using a technique known as "score and snap."
[0019] Although the prior art includes a multiplicity of
gypsum-based wallboard laminates, few of those inventions disclose
noise-attenuation characteristics that meet government noise
standards, which standards typically require wallboard assemblies
to achieve an STC rating of at least 50. The inventions that
disclose noise-attenuation characteristics consist of multiple
layers of the same or different materials bonded together, with
each layer being uniform in material. While each layer is designed
to serve a particular purpose within the laminate, the laminate's
spatial uniformity in its plane reduces its effectiveness in
attenuating noise, especially noise consisting of a broad range of
frequencies. Moreover, those inventions that disclose
noise-attenuation characteristics are substantially more difficult
to handle and install than standard gypsum panels.
[0020] Hence, there is a need for a wallboard panel that largely
mirrors the weight, handling, and installation characteristics of a
standard gypsum panel, but that also meets governmental
noise-attenuation standards.
SUMMARY OF THE INVENTION
[0021] The present invention is a composite laminate wallboard
panel for use in place of standard gypsum panels. The invention is
similar in weight to a standard gypsum panel and can be handled and
installed in a manner similar to such panels. However, the
invention also provides superior noise attenuation, thermal
insulation, fire resistance, shear strength, mold resistance, and
moisture resistance.
[0022] Noise attenuation in the current invention is enhanced over
panels constructed from the prior art, since laminated layers of
the current invention have rough, non-uniform surfaces and/or
section properties. Surface non-uniformity may be accomplished by
embossing, debossing, dimpling, scoring, kerfing, grooving, boring,
perforating, scalloping, corrugating, routing, and/or performing
other actions that produce surface non-uniformities, such as
bonding or attaching in some manner patches of the same or
different materials to the surface of the layer. The sizes, shapes,
and spatial distribution of these surface features are generally
non-uniform, and different types of features can be combined to
yield the desired effect. Non-uniformity of the section properties
of a layer may be accomplished by embedding one or more different
materials and/or voids non-uniformly within the layer, or by
constructing the layer as a patchwork of different materials. The
sizes, shapes, material types, and spatial distribution of these
embedded materials or voids are generally non-uniform, and
different embedded features can be combined to yield the desired
effect. Further, surface and section non-uniformity may be employed
together in the same layer to yield the desired effect.
[0023] A preferred embodiment of the invention disclosed herein
consists of a five-layer laminate structure arranged in the
following manner. A core layer consisting of a thin sheet of
absorbent paper is coated on each side with a layer of viscoelastic
adhesive. On the exposed side of one these layers of adhesive is
placed a standard gypsum panel, while on the exposed side of the
other layer of adhesive is placed a fire resistant panel, such as
one constructed from Magnesium Oxide (MgO), of dimensions that are
similar to those of a standard gypsum panel.
[0024] In a second embodiment of this invention, the fire resistant
panel of the preferred embodiment is replaced by a standard gypsum
panel or a panel of a different material (e.g., polymer, metal,
wood, or ceramic, wherein these materials may be in cellular or
foamed forms) that has dimensions similar to those of a standard
gypsum panel.
[0025] In a third embodiment of this invention, the core paper
layer (and optionally either of the two viscoelastic adhesive
layers) of the preferred embodiment is omitted from the
construction of the invention.
[0026] In a fourth embodiment of this invention, the core paper
layer of the preferred embodiment is replaced with a layer of a
different material (e.g., polymer, metal, wood, or ceramic, wherein
these materials may be in cellular or foamed forms) that has
dimensions similar to those of the core paper.
[0027] In a fifth embodiment of this invention, one or both of the
exposed surfaces of the preferred embodiment is augmented by a
layer of viscoelastic adhesive and a standard gypsum panel (or a
panel of one of the aforementioned alternative materials) that has
dimensions similar to those of a standard gypsum panel.
[0028] In a sixth embodiment of this invention, the standard gypsum
panels of the previously described embodiments are replaced by
gypsum panels that have no paper backing on either or both of their
surfaces or, alternatively, by gypsum panels that have a non-paper
backing on either or both of their surfaces.
[0029] The thicknesses of the various lamination layers within a
single panel of the current invention should be chosen to provide
the desired level of noise attenuation, thermal insulation, fire
resistance, shear strength, mold resistance, and moisture
resistance. Suitable thicknesses of the panels made from gypsum,
MgO, and the aforementioned alternative materials would be in the
range from 1/16'' to 3/4''. Suitable thicknesses of layers of
viscoelastic adhesive range from 1/128'' to 1/8''. Suitable
thicknesses of the layers of paper range from 1/128'' to 1/16'',
although the thicknesses of the aforementioned alternative material
layers may lie outside of this range.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Embodiments and characteristics of the present invention are
illustrated by way of example, and not by way of limitation, in the
following drawings.
[0031] FIG. 1 shows a five-layer laminar structure that was
constructed with this invention and that attenuates the
transmission of sound.
[0032] FIG. 2 shows a three-layer laminar structure that was
constructed with this invention and that attenuates the
transmission of sound.
[0033] FIG. 3 shows test results of the sound attenuation
properties of the embodiment of this invention that is shown in
FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] The following description is intended to be exemplary only
and not to in any way limit the scope or objective of the
invention. The preferred embodiments referred to below describe a
laminate composite wallboard system. This invention, however, is
not limited to wallboards, but can be used in any application where
a noise-attenuating building material is desired.
[0035] FIG. 1 shows a cross-section of a preferred embodiment of a
wallboard panel constructed with the present invention, which
wallboard panel is a five-layer laminate consisting of a standard
gypsum panel 10 whose non-facing side is adjacent to a layer of
viscoelastic adhesive 20. On the side of the viscoelastic adhesive
20 away from the gypsum panel 10 is a layer of absorbent paper 30.
Then, on the side of the absorbent paper 30 away from the
viscoelastic adhesive 20 is another layer of viscoelastic adhesive
40. Then, on the side of viscoelastic adhesive 40 away from the
absorbent paper 30 is an MgO panel 50.
[0036] Some or all of the layers of this invention may be
non-uniform in thickness, heterogeneous in material, and/or
non-flat by virtue of being embossed, debossed, dimpled, scored,
kerfed, grooved, bored, perforated, scalloped, corrugated, routed
and/or otherwise made to be non-flat. All such non-uniform features
may be distributed non-uniformly in the plane of the layer. For
example, embossings and/or other non-uniform features may be used
in combination and distributed randomly or have non-uniform
dimensions.
[0037] The current invention introduces non-uniformity and
heterogeneity in the plane of the panel to achieve greater noise
attenuation via three mechanisms: [0038] 1. By developing more
complex and non-uniform strain states in energy (noise) absorbing
materials, such as elastic adhesives, the materials' natural
damping capabilities may be enhanced and better noise attenuation
may be achieved over a wider frequency range. These more complex
strain states are generated by the complex shapes of individual
layers in the current invention. [0039] 2. Sound waves in the plane
of the panel will be dissipated better by the inherent
heterogeneity in the panel. For example, complex shapes that are
non-uniform in the plane (as well as patched materials) assist in
deflecting in-plane waves, thereby making the transmission of sound
less efficient in these panels. [0040] 3. Non-uniform panels reduce
energy transfer between parallel panels by modifying modal
deformations. When the vibratory mode shapes of parallel panels are
different, their energy transfer capability (efficiency) is greatly
reduced. The mode shapes of these panels are affected by the
non-uniform features in the current invention.
[0041] FIG. 2 shows a cross-section of another preferred embodiment
of a wallboard panel constructed with the present invention, which
wallboard panel is a three-layer laminate consisting of a standard
gypsum panel 60 whose non-facing side is adjacent to a layer of
viscoelastic adhesive 70. On the side of the viscoelastic adhesive
70 away from the gypsum panel 60 is an MgO panel 80.
[0042] FIG. 3 shows test data representing the sound transmission
attenuation (in dB) as a function of frequency using an
industry-standard assembly constructed from the embodiment of this
invention shown in FIG. 2. The thicknesses of the laminate
components of said embodiment are: 3/8'' gypsum panel 60; 1/64''
viscoelastic adhesive 70; and 6 mm (0.236'') MgO panel 80. The test
configuration was standard in the trade and was performed by an
independent testing laboratory in compliance with the ASTM E90-04
and ASTM E413-04 standards using standard 2''.times.4'' wood stud
construction.
[0043] Testing of the industry-standard assembly constructed from
the embodiment of this invention shown in FIG. 2 produced an STC
value of 52. It is well known in the field that an STC value of 34
can be achieved with an industry-standard assembly constructed with
commercially available 5/8'' gypsum panels, which thickness is
equivalent to the embodiment of this invention that was tested and
whose test results are referred to above. Hence, the
industry-standard assembly using the embodiment of FIG. 2 produced
an 18-point STC improvement over standard gypsum panels. This STC
difference indicates that an industry-standard assembly based upon
the present invention transmits 71% less noise through a similar
assembly based on an equivalent thickness of commercially available
gypsum panels.
[0044] Various changes and modifications of the above-mentioned
embodiments will be apparent to those skilled in the art. Hence, it
is not intended that the scope of this invention be limited by the
details of the above description.
* * * * *