U.S. patent application number 11/489177 was filed with the patent office on 2008-01-24 for inorganic fiber insulation product.
Invention is credited to Ralph Michael Fay.
Application Number | 20080020206 11/489177 |
Document ID | / |
Family ID | 38971793 |
Filed Date | 2008-01-24 |
United States Patent
Application |
20080020206 |
Kind Code |
A1 |
Fay; Ralph Michael |
January 24, 2008 |
Inorganic fiber insulation product
Abstract
Insulation formed by blowing nodules of inorganic fiber
insulation coated with a water or other liquid activated binder in
intimate contact and having a low moisture content in the just
installed insulation of less than about 20 wt. percent is
disclosed. The majority of the nodules have a maximum dimension of
about 0.5 inch and have particles or a fiber web of a water or
other liquid activated adhesive on their outer surface producing a
high tack value with a very low moisture content. The insulation
can be used to insulate building structures, including vertical
wall cavities of buildings, without having to use any insulation
securing means. The high tack value permits the sprayed-on
insulation to stick to even the most stick-resistant sheathing
product. The low moisture content of less than 20 wt. percent and a
density of less than about 3 lbs. per cubic foot permits rapid
drying of the installed installation and a lower elapsed time
before the wallboard can be installed, and the insulation has a low
density to produce conventional R values of at least R 13. Methods
of making dry nodules coated with the reactivatable adhesive are
disclosed as are methods of using the dry nodules to insulate
building cavities.
Inventors: |
Fay; Ralph Michael;
(Lakewood, CO) |
Correspondence
Address: |
JOHNS MANVILLE
10100 WEST UTE AVENUE
LITTLETON
CO
80127
US
|
Family ID: |
38971793 |
Appl. No.: |
11/489177 |
Filed: |
July 19, 2006 |
Current U.S.
Class: |
428/375 |
Current CPC
Class: |
E04B 1/7604 20130101;
Y10T 428/2933 20150115 |
Class at
Publication: |
428/375 |
International
Class: |
D02G 3/00 20060101
D02G003/00 |
Claims
1. Just installed thermal and acoustical insulation comprising from
about 0.5 to about 10 wt. percent of a water or other liquid
activated adhesive on nodules comprising inorganic fiber having an
average fiber diameter of about 2.5 microns or less, the majority
of the nodules having a maximum dimension of about 0.5 inch, the
nodules being in intimate contact with each other to form the just
installed insulation, the just installed insulation having a liquid
content of no more than 20 wt. percent, and the insulation having
an R value of at least 13 and a density of less than about 3 PCF
after drying.
2. The insulation of claim 1 wherein the inorganic fibers comprise
virgin glass fibers, the liquid content of the just installed
insulation is in the range of about 7 to about 17 wt. percent.
3. The insulation of claim 1 wherein the nodules comprise glass
fibers bonded together with a cured resin at one or more of the
locations where two or more of the fibers cross one another, the
liquid content of the just installed insulation is in the range of
about 7 to about 15 wt. percent and the nodules have less than
about 5 wt. percent, on a dry basis, of water activated adhesive on
their surface portion.
4. The insulation of claim 1 wherein at least about 70 percent of
the nodules have a maximum dimension of one-half inch.
5. The insulation of claim 1 wherein at least about 80 percent of
the nodules have a maximum dimension of one-half inch.
6. The insulation of claim 1 wherein at least about 90 percent of
the nodules have a maximum dimension of one-half inch.
7. The insulation of claim 2 wherein at least about 70 percent of
the nodules have a maximum dimension of one-half inch.
8. The insulation of claim 2 wherein at least about 80 percent of
the nodules have a maximum dimension of one-half inch.
9. The insulation of claim 2 wherein at least about 90 percent of
the nodules have a maximum dimension of one-half inch.
10. The insulation of claim 3 wherein at least about 70 percent of
the nodules have a maximum dimension of one-half inch.
11. The insulation of claim 3 wherein at least about 80 percent of
the nodules have a maximum dimension of one-half inch.
12. The insulation of claim 3 wherein at least about 90 percent of
the nodules have a maximum dimension of one-half inch.
13. The insulation of claim 1 wherein the activated adhesive is a
hot melt adhesive.
14. The insulation of claim 2 wherein the activated adhesive is a
hot melt adhesive.
15. The insulation of claim 3 wherein the activated adhesive is a
hot melt adhesive.
16. The insulation of claim 5 wherein the activated adhesive is a
hot melt adhesive.
17. The insulation of claim 7 wherein the activated adhesive is a
hot melt adhesive.
18. The insulation of claim 10 wherein the activated adhesive is a
hot melt adhesive.
19. Dry nodules of inorganic fibers having an average diameter of
about 2.5 microns or less, the major portion, by weight, of the
nodules being no more than about 0.5 inch in diameter, comprising
up to about 10 wt. percent of a water or other liquid reactivatable
adhesive on the surface portion.
20. The dry nodules of claim 19 wherein the adhesive is a water
activatable hot melt adhesive.
21. The dry nodules of claim 19 wherein the adhesive is a water
reactivatable adhesive.
22. The dry nodules of claim 19 wherein the reactivatable adhesive
is present in an amount of less than about 7 wt. percent of the
nodules.
23. The dry nodules of claim 19 wherein the reactivatable adhesive
is present in an amount of less than about 5 wt. percent of the
nodules.
24. The dry nodules of claim 20 wherein the reactivatable adhesive
is present in an amount of less than about 7 wt. percent of the
nodules.
25. The dry nodules of claim 21 wherein the reactivatable adhesive
is present in an amount of less than about 7 wt. percent of the
nodules.
26. The dry nodules of claim 19 wherein the reactivatable adhesive
is present in an amount of less than about 4 wt. percent of the
nodules.
27. The dry nodules of claim 20 wherein the reactivatable adhesive
is a hot melt adhesive present in an amount of less than about 5
wt. percent of the nodules.
28. The dry nodules of claim 20 wherein the reactivatable adhesive
is present in an amount of less than about 4 wt. percent of the
nodules.
29. The dry nodules of claim 21 wherein the reactivatable adhesive
is present in an amount of less than about 5 wt. percent of the
nodules.
30. The dry nodules of claim 21 wherein the reactivatable adhesive
is present in an amount of less than about 4 wt. percent of the
nodules.
31. The dry nodules of claim 19 wherein at least 70 wt. percent of
the nodules have a diameter of less than about 0.5 inch.
32. The dry nodules of claim 20 wherein at least 70 wt. percent of
the nodules have a diameter of less than about 0.5 inch.
33. The dry nodules of claim 21 wherein at least 70 wt. percent of
the nodules have a diameter of less than about 0.5 inch.
34. The dry nodules of claim 27 wherein at least 70 wt. percent of
the nodules have a diameter of less than about 0.5 inch.
35. The dry nodules of claim 29 wherein at least 70 wt. percent of
the nodules have a diameter of less than about 0.5 inch.
36. A method of insulating cavities in a building comprising
blowing pieces of fibrous insulation comprising a water
reactivatable adhesive through a hose while suspended in an air
flow spraying water onto the pieces of fibrous insulation at the
end of the hose or in a nozzle at the end of the hose and directing
the wetted pieces of fibrous insulation into a building cavity to
form just installed insulation, the improvement comprising using as
the pieces of fibrous insulation dry nodules comprising inorganic
fibers having an average diameter of about 2.5 microns or less, the
major portion, by weight, of the nodules being less than about 0.5
inch in diameter, and wherein the amount of water sprayed onto the
dry nodules is such that the moisture content of the just installed
insulation is less than about 20 wt. percent and wherein the
reactivatable adhesive is coated on the surface portion of the
nodules and is present in an amount of 0.5 to about 10 wt. percent
of the dry nodules.
37. The method of claim 36 wherein the amount of water sprayed onto
the dry nodules is such that the moisture content of the just
installed insulation is less than about 17 wt. percent and the
amount of reactivatable adhesive on the nodules is about 2 to about
5 wt. percent.
38. The method of claim 36 wherein the water activatable adhesive
is a hot melt adhesive.
39. The method of claim 37 wherein the water activatable adhesive
is a hot melt adhesive.
40. A method of making dry nodules comprising inorganic fibers
having an average diameter of about 2.5 microns or less, the major
portion, by weight, of the nodules being no more than about 0.5
inch in diameter, and a water or other liquid reactivatable
adhesive on the surface portion of the nodules comprising the steps
of; 1) feeding virgin fiber or fiber bonded together with a dried
and cured resin into a nodulating machine, 2) spraying, spreading
or slinging the water or other liquid reactivatable adhesive onto
the surface portion of the nodules while the nodules are free
falling or tumbling in a mixer to produce nodules having a coating
0.5 to about 10 wt. percent of the water or other liquid
reactivatable adhesive, and 3) drying or cooling the coated nodules
to solidify the coating of activatable adhesive to produce dry
nodules,
41. The method of claim 40 comprising a further step of compressing
and packaging the dry nodules in moisture proof containers.
42. The method of claim 40 wherein at least 70 wt. percent of the
nodules have a diameter of no more than about 0.5 inch.
43. The method of claim 41 wherein at least 70 wt. percent of the
nodules have a diameter of no more than about 0.5 inch.
44. The method of claim 40 wherein the coating comprises about 2 to
about 5 wt. percent of the dry nodules.
45. The method of claim 43 wherein the coating comprises about 2 to
about 5 wt. percent of the dry nodules.
Description
[0001] The present invention involves fibrous thermal and acoustic
insulation produced by spray application, the resultant sprayed-in
insulation and the method of making the latter.
BACKGROUND
[0002] It is conventional to pump or blow loose-fill fibrous
insulation into attics, walls, wall cavities, etc. of houses and
other buildings. It is also known to add powdered binder
(adhesive), de-dusting oil, anti-static agents to clumps of
fiberglass or other fibrous insulation prior to a blowing nozzle to
prevent settling, static discharge and or to reduce dust in the
area of application during installation. The application of a
liquid binder dispersion, or water to activate pre-added powdered
adhesives, to create adhesive/cohesive tack strength is also known.
Such technology can be found in U.S. Pat. Nos. 4,710,4804,
4,804,695, 5,641,368 and others, but as stated in U.S. Pat. No.
5,952,418, at least one of these systems suffer from problems of
blockage of adhesive nozzles and/or a blowing hose. When these
systems are used to insulate cavities between vertical or generally
vertical studs or other structural members, a high moisture
content, as high as 50% of the dry weight of the just installed
insulation, is required to cause the insulation to adhere properly
to various substrates that comprise the wall cavities of the
cavities or building structure. Such high moisture contents require
long drying times, typically 2 or more days, before wall board can
be installed to avoid potential mold related problems, such as mold
growth on the paper facing of the wallboard.
[0003] It is also known to spray clumps of fiber glass insulation
coated with water and a non-foaming binder into wall cavities
followed by rolling at least about an inch of excess insulation
thickness down to the thickness of the wall studs followed by
spraying additional clumps of insulation into any thin spots or
unfilled cavities and then rolling or scrubbing off excess
thickness down to the thickness of the studs. As disclosed in U.S.
Pat. No. 5,641,368, the installed insulation is reported to have a
moisture content of less than about 35 wt. percent. When using
lower moisture contents, the clumps do not adhere sufficiently to
certain conventional linings of wall cavities causing collapse and
lower productivity. Rolling spray applied insulation can result in
spring-back in some areas and adds an undesirable additional step
to the installation process, the additional step of spraying a
second time slows the building installation process and adds
substantial cost to the insulating part of the building
process.
[0004] Cellulose products require installed densities ranging from
2 to 3 PCF to achieve an R-13 level in thermal insulation in a
standard wall cavity. These products cannot achieve an R-15 level
due to density limitations and thermal limitations of the cellulose
material. Most existing loose-fill mineral fiber products require
installed densities of at least about 1.2 to 1.5 PCF to achieve an
R-13 level of insulation and densities ranging from about 1.8 to
2.5 PCF to achieve an R-15 level in a standard 2.times.4 cavity.
Although high density is required for cellulose application, the
cellulose material is usually lower in cost than most mineral fiber
products in similar applications and at similar R-values levels.
Therefore, a need exists for a low density, cost competitive
inorganic fiber product to use instead of cellulose. The present
invention provides this capability.
[0005] It is also known to blow dry or semi-dry loose fill
insulation into wall cavities that are vertical or substantially
vertical, by first installing a retaining means such as netting,
cardboard baffles, or other physical means. Installing the
restraining means requires an extra work day in a typical size
house and substantially adds to the installed cost of the
insulation. It is known to blow fiber glass nodules coated with
water and binder, the binder added with the water, into cavities
producing a just-installed insulation having a relatively low
moisture content, compared to about 35 wt. percent.
[0006] With concerns of mold problems in walls of various kinds of
structures reaching serious levels, a sprayed-on insulation,
particularly an inorganic fiber insulation with low moisture
sorption potential that contains a substantially lower moisture
content soon after installation is much needed. A need also exists
to ensure that the insulation material will uniformly fill the
cavities within a given structure and adhere well to the walls of
the cavity to avoid collapse, gaps, settling and voids, the
presence of which will substantially degrade insulation
performance. The material should also be cost competitive with high
productivity to ensure commercial success. The present invention
addresses these needs.
SUMMARY OF INVENTION
[0007] The present invention includes coated fibrous nodules coated
with a reactivatable or remoistenable adhesive using processes of
the invention and used in a process of the invention to make a
sprayed-on thermal and acoustic insulation product having a very
low just installed moisture content. The just installed insulation
product is formed in place by spraying nodules comprised of
inorganic fiber and a water reactivatable adhesive or binder,
drying the coated nodules delivering the dry coated nodules to a
nozzle or end of a transporting hose, spraying water or other
reactivating liquid into the coated nodules to activate the
reactivatable adhesive before the resultant insulating mixture
impacts in the cavity or other surface being insulated.
Intermediate steps of packaging the dry coated nodules and then
after the packages of dry coated nodules are on the building site,
opening the packages and dumping the dry coated nodules into a
blowing machine are added to one or more of the processes of the
invention. The coated nodules are made from inorganic fiber and
most typically glass fibers. The inorganic fibers used to make the
nodules can be virgin fiber, virgin fiber having a dedusting oil on
their surfaces, and fibers bound together with a cured resin
binder. These fibers can also have one or more other functional
additives like one or more silicones, biocides, pesticides,
fungicides, fire retardants, phase change materials, etc. in the
binder, oil or on or with the virgin fibers. The terms
reactivatable and remoistenable often mean essentially the same
thing herein, but sometimes the adhesives used in the invention are
described by some as reactivatable and by others as remoistenable.
Both terms mean that the adhesive is activated or reactivated by
contact with water or other activating liquids producing a tacky
condition.
[0008] Novel features of the present invention include the size of
the fibrous nodules and the small amount of water or activating
liquid used to reactivate or remoisten the reactivatable adhesive,
significantly less than heretofore used. The major portion of the
weight of the nodules have a maximum dimension of one-half inch, to
produce a very high tackiness, going into cavities within a
building structure, more typically at least about 60 wt. percent of
the nodules have a maximum dimension of 0.5 inch, even more
typically at least about 70 wt. percent having nodules of this
size, still more typically at least about 80 wt. percent having
nodules of this size and most typically at least about 85 or 90 wt.
percent having nodules having a diameter of less than about 0.5
inch The amount of moisture in the just installed insulation of the
invention is typically less than about 20 wt. percent, usually less
than about 17 wt. percent, more typically less than about 15 wt.
percent, even more typically less than about 12 wt. percent, still
more typically less than about 10 wt. percent and most typically
less than about 7 wt. percent. The amount of reactivatable,
remoistenable adhesive on the nodules and in the just installed
insulation is less than 10 wt. percent, typically less than about 7
wt. percent and most typically in the range of about 5 to about 2
wt. percent. The density of the just installed insulation is less
than about 3 PCF (after drying) and more typically less than about
2 PCF to produce insulation in the cavity of having an R value of
at least 13 (about 1 PCF).
[0009] The dry coated nodules of fibrous insulation are produced by
a hammer mill or other nodule making machine, first coated with a
liquid activatable adhesive, dried and optionally packaged. Later
the dry coated nodules are fed to a blowing wool machine and at the
end of the transporting hose or nozzle on the end of said hose, the
dry coated nodules are sprayed with an reactivating liquid, most
typically water, or another activating liquid producing activated
insulating nodules having very tacky surfaces causing the activated
insulating nodules to adhere to the cavity surfaces and to each
other on impact inside a cavity, producing intimate contact and
producing just installed insulation having enough initial tack to
resist slumping and collapse during installation and until enough
moisture evaporates to form an even stronger bond. The activated
insulating nodules also adhere to all types of cavity construction
materials which is key to resisting rebound and collapse. The term
"just installed" means within one hour, more typically within about
30 to 45 minutes and most typically about 10 to about 40 minutes of
installation, and the term "generally vertical" includes angles of
from about 60 degrees to 90 degrees, or vertical. The activated
nodules of the invention can also be used to insulate ceiling,
overhead, cavities. Up to one hour of time can be required to
remove and test samples of the insulation, although often a sample
can be taken and measured in less than about 15-30 minutes.
Normally very little drying takes place in the just installed
insulation during this initial hour of time.
[0010] The final insulation product of the invention has unique
characteristics including:
[0011] 1. Inorganic fiber of small diameters having very low
moisture sorption potential to facilitate drying time and to
minimize mold growth potential and producing high thermal
performance at low densities to permit a variety of R-values in a
standard wall cavity and at different widths and depths while
meeting newly proposed building code requirements, and also
producing shorter drying times than prior art wet sprayed in
insulation.
[0012] 2. Comprised of small nodules that permit a variety of
commercial blowing machines, including those specifically designed
for blowing cellulose insulation, to produce a uniform cavity fill,
high quality surface appearance, a faster rate of application,
minimal plugging potential and high thermal and acoustical
performance. With the majority, or more, of the nodules having a
maximum dimension of about one-half inch, more typically at least
about 70 percent of the nodules are smaller than one-half inch,
more typically at least about 80 percent and even more preferably
at least about 90 percent. Most typically the majority of the
nodules are smaller than one-quarter inch and the smaller the
nodules the better with at least about 70 percent being smaller
than one-quarter inch, at least about 80 percent and at least about
90 percent being this size is even better.
[0013] 3. Small nodules bonded together with a liquid activated
binder or adhesive while avoiding spray jet or nozzle plugging,
providing excellent tackiness for adhering to each other and to all
types of building substrate materials describes additional positive
features of the invention.
[0014] Typically the binder is a water-based or hot melt
reactivatable, remoistenable, adhesive, but any dry binder or dry
adhesive capable of being reactivated with water or other liquid to
reach a tackiness of the extent that the just installed insulation
does not collapse or slump, are suitable. The binder/adhesive,
usually including one or more resins or polymers should produce
sufficient initial tackiness to permit vertical wall cavities,
including even ceiling cavities, of various depths to be filled by
spraying without settling, slumping or collapsing until the
insulation is dry enough to apply the interior wall board, expanded
metal or other board product. Typically the binder is present in an
amount in the range of about 0.5 wt. percent to about 10 wt.
percent (dry solids basis of the installed insulation product) and
preferably the amount of water present in the just installed
product is in the range of about 7-12 wt. percent. Importantly the
just installed product of the present invention will have R values
as high as about 15 while containing typically less than about
0.47-0.5 or 0.55 lbs. of liquid per standard wall cavity, more
typically only about 0.12 to about 0.35 lbs. of water in a standard
wall cavity. A standard wall cavity is formed by vertical
commercially available standard 2.times.4s, 8 feet high and 16
inches on center. Hereafter the term "standard cavity" will be used
to describe this size cavity The moisture content of the just
installed insulation can be below about 2-5 wt. percent for some
building substrate materials and for attic installations, but is
often higher for vertical wall cavities. Also, more insulation
material will be required to fill wall applications because of
closer packing (see FIG. 6) of the coated nodules during
installation versus attic installations. It is not necessarily just
the percent moisture in the product that is critical to drying time
of the just installed insulation, but rather the amount (lbs.) of
water per standard cavity, or other unit volume, that is most
critical.
[0015] Preferably the inorganic fibers having an average diameter
of less than about 3 microns, more preferably an average diameter
of about 2.5-2 microns or less and most preferably, for insulating
performance, an average diameter of about 1 micron or less.
Preferably the inorganic fibers are glass fibers, but other fibers
including slag wool, mineral wool, rock wool, ceramic fibers and
carbon fibers are included. Any kind of stable glass fibers are
suitable but preferably the glass fibers contain at least about 8%
B.sub.2O.sub.3 as an infrared blocker to enhance thermal
performance at low installed densities. Other infrared radiation
blocking constituents (reflecting, scattering and/or absorbing) can
also be included in the glass chemistry or can be applied to the
glass fiber as surface coatings, mixed with the glass fibers or
introduced in the water containing the resin adhesive to enhance
thermal performance. Other performance enhancing additives can also
be applied to the glass surface or nodule surface or mixed with the
glass fibers. These can include for example microencapsulated phase
change materials, fire retardants, fungicides or pesticides.
[0016] Typically the dry nodules are smaller than about one inch
diameter, more typically most or all of the coated nodules less
than about one-half inch in length, width and thickness, or
diameter, but larger sizes can be used if an acceptable surface
appearance can be obtained. Most desirably a majority, or more, of
the nodules are less than one-quarter inch in length, width and
thickness, or diameter. While the size of the nodules is important
to optimum performance in most all aspects, it is difficult to
determine the actual dimensions of a large number of nodules
because of their irregular shape, their compressibility, and
tendency to adhere together. Observance has indicated that most
preferable size is that at least 90 percent of the nodules have a
dimension of about one-quarter inch or less, but that percentage
can also be at least 80, and at least 70. The smaller the nodules,
the better the performance generally. The nodules of inorganic
fibrous insulation can also contain conventional amounts of one or
more anti-static agents, one or more of de-dusting oils,
hydrophobic agents such as a silicone, biocides and fire retardants
applied to the fibers, a binder holding the fibers together when
that type of fiber glass insulation is used to form the nodules, or
to the nodules in a conventional manner. By dry nodules is meant
nodules having less than about 1 wt. percent moisture to bone dry,
more typically less than about 0.5 percent moisture and most
typically in the range of about 0.0 to about 0.3 wt. percent.
[0017] The coated nodules when sprayed into a cavity to form the
present insulation product form into a uniform thermal/acoustical
insulation mass in a wall cavity having a density preferably of 3
lbs./cu. ft. (PCF) or less, more preferably of 2 PCF or less and
most preferably 1 PCF or less. The density will depend to some
extent upon the R value desired. For a standard cavity the
preferred product of the present invention will produce a installed
insulation in a standard cavity that when dry will have a density
within the range of about 0.8 to about 1 PCF and an R value of
about 13, or a density in the range of about 1.5 to about 1.8 PCF
and an R value of about 15. This low density and a low moisture
content results in a superior insulation product having low cost
and a substantially faster drying time than previous wet blown-in
wall cavity insulation.
[0018] When the word "about" is used herein it is meant that the
amount or condition it modifies can vary some beyond that so long
as the advantages of the invention are realized. Practically, there
is rarely the time or resources available to very precisely
determine the limits of all the parameters of ones invention
because to do would require an effort far greater than can be
justified at the time the invention is being developed to a
commercial reality. The skilled artisan understands this and
expects that the disclosed results of the invention might extend,
at least somewhat, beyond one or more of the limits disclosed.
Later, having the benefit of the inventors disclosure and
understanding the inventive concept and embodiments disclosed
including the best mode known to the inventor, the inventor and
others can, without inventive effort, explore beyond the limits
disclosed to determine if the invention is realized beyond those
limits and, when embodiments are found to be without any unexpected
characteristics, those embodiments are within the meaning of the
term about as used herein. It is not difficult for the artisan or
others to determine whether such an embodiment is either as
expected or, because of either a break in the continuity of results
or one or more features that are significantly better than reported
by the inventor, is surprising and thus an unobvious teaching
leading to a further advance in the art.
BRIEF DESCRIPTION OF DRAWINGS
[0019] FIG. 1 is a schematic view of an exemplary embodiment of a
system for forming an insulation particle/air suspension.
[0020] FIG. 2 is a schematic of processes of the invention for
making coated insulation nodules of the invention.
[0021] FIG. 3 is a schematic of one process of the invention for
making coated insulation nodules of the invention.
[0022] FIG. 4 is a schematic of other processes for making dry
coated insulation nodules of the invention.
[0023] FIG. 5 is an approximation of a just installed prior art
insulation clumps in a portion of a building cavity.
[0024] FIG. 6 is an approximation of a just installed insulation
comprising nodules and low moisture content according to the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] It is well known how to make loose-fill clumps of inorganic
fibers for forming blown-in insulation. The inorganic fiber used in
the present invention can be glass fibers, mineral wool, slag wool,
or a ceramic fiber and preferably is fiberglass, most preferably
containing in the glass a boron oxide content of at least about 8
percent. Preferably the fiber has a mean or average fiber diameter
less than or equal to about 3 microns such as an average fiber
diameter of 2.5 microns or less, more preferably equal to or about
2 microns, even more preferably equal to or less than about 1.5
microns with the most preferred mean diameter being about 1 micron
to produces an insulation product having high thermal performance
at low installed densities. FIG. 5 is an approximation of just
installed insulation comprising fiber clumps 11 in a portion of a
building cavity. The clumps 11 do not pack together well because of
their larger size.
[0026] Nodules are defined above as very small bundles of
insulation fibers that are equal to or less than about one inch,
more typically most of the nodules are not greater than about 1/2
inch in length, width and thickness or diameter and most typically
almost all of the nodules are this latter size or smaller, i.e. at
least about 90 percent of the nodules. Preferably, the size of at
least the majority of the nodules in all three dimensions or
diameter is 1/4 inch or less. Clumps are defined as having a
physical size greater than that of these nodules of fiber. Most
conventional mineral fiber loose-fill insulation products designed
for attic application consist of clumps of fibrous material. These
types of products will not provide the desired uniformity and
quality surface appearance required for spray-applied application
to meet stringent inspection standards and to ensure consistent
thermal performance. In addition, if these products were used for
spray applied application, they would produce just installed
insulation looking like that shown in FIG. 5, not be readily able
to closely pack in the building cavity, i.e. fit together snug and
tight as do the nodules 8 shown in the just installed insulation 12
formed according to the invention and shown in FIG. 6. The larger
clumps 11 would be more prone to one or more of plugging, not
allowing for adequate wetting when binder is applied and/or not
providing the required R-value at cost competitive installed
densities.
[0027] Referring to FIG. 1 an exemplary system 1 for forming just
installed insulation in accordance with the present invention in
building cavities is shown. A blowing machine 2 can be connected to
receive insulation nodules of the invention. The blowing machine 2
suspends the coated insulation nodules in air and blows the
suspension from an outlet 3. An optional booster fan 4 can be
connected to directly receive a flow of the suspension from the
outlet 3 of the blowing machine 2. A hose 6 can be connected to
receive the flow of the suspension from the booster fan 4, and
convey such flow proximate to the surface 12 to be insulated, such
as a surface of a wall cavity. The suspension 8 can be directed at
the surface 12. The suspension 8 can be ejected from the hose 6 via
an optional nozzle 5 connected to the end of the hose 6. A the
optional nozzle 5 is not necessary because one or more liquid spray
tips or jets can be fastened to a metal or polymer collar
(conventional and not shown) on the hose at or near its exit end,
also having a handle, if desired, but a nozzle is desirable to more
accurately place the suspension of the coated, tacky insulating
nodules. Water or another reactivating liquid is applied to the
coated insulation nodules of the suspension 8 by at least one spray
tip arranged at the nozzle 5. The water or other liquid reactivates
or remoistens the reactivatable adhesive coating on the nodules to
produce a tacky surface. The reactivating or remoistening liquid is
supplied from a source 20 using a pressure line 7 and a pump 22. A
relatively low amount of reactivating, remoistening liquid is added
to the coated insulation nodules to produce a moisture or liquid
content in the just installed insulation 14.
[0028] Each blowing machine has an outlet through which the nodules
of insulation are ejected as a rapidly moving air suspension. One
end of a hose is connected to the outlet. The other end of the hose
can be in the location that the operator will need for installing
the insulation. The blowing machine hose can be up to about 200
feet long and can have a diameter of about 2.5 inches to about 4
inches or so, depending upon the type of blowing machine and the
intended use or particular application. The blowing machine mixes
the nodules with air and blows the resulting air suspension out the
outlet and through the hose. A nozzle is normally attached to the
end of the hose, the nozzle usually having one or more handles for
the operator to hold to aim the nozzle in the proper direction and
orientation for spraying the cavities. Nozzles are known as is
shown in U.S. Pat. Nos. 5,641,368 and 5,921,055. The nozzle used in
the present invention has preferably two or more jet spray tips for
spraying the water or other liquid onto the nodules of fibrous
insulation near the exit end of the nozzle, preferably at or past
the exit end. Other non-aqueous liquids suitable for activating the
adhesive or binder includes liquids that activate the adhesive, but
that are not explosive or an environmental hazard.
[0029] An adjustable rate pump connected to a use tank of water or
activating liquid, or directly to a water supply to provide water
or other liquid at the proper rate and pressure to the jet spray
tips through one or more flexible hoses to properly coat the
nodules with the desired amount of water or other liquid. One or
more jet spray tips can be used to apply the water or liquid to the
nodules at an elevated pressure supplied by the pump. Usually two
or three spray tips are used opposite each other across the moving
column of suspended clumps and/or nodules. Many different types of
jet spray tips can be used and one that performs well is Spray
Systems Company's 25 degree flat spray Unijet.RTM. tip. Another jet
spray tip that is suitable is Spray Systems Company's 65 degree
Unijet.RTM. tip.
[0030] The resultant wet binder or adhesive coated clumps and/or
nodules of mineral fiber insulation contain a moisture content of
less than about 20-25 wt. percent, based on the dry weight of the
clumps and/or nodules, preferably less than about 12 percent, more
preferably less than about 10 wt. percent and can be down to less
than about 7 weight percent or even lower depending on the type of
building cavity or surface being insulated and depending on the
nature of the binder or adhesive. At these weight percentages, the
initial water content in a standard cavity would range from about
0.12 to about 0.35 lbs. for an R13 application for installed
density ranging from about 0.8 to about 1.0 PCF.
[0031] Fibrous loose-fill insulation is subject to all three modes
of heat transfer--radiation, conduction and convection. Convection
can be minimized by reducing size of the nodules of loose
insulation and preferably by producing more consistently sized
nodules to limit potential air passages (voids) that can occur
within the installed material. Convection is also minimized with a
uniform cavity fill with no gaps or voids caused by bridging of the
clumps, and with a fill that is such that the insulation is even
with the framing faces when installation is complete. Small nodule
size also makes this possible. If convection is kept to a minimum,
infrared thermal radiation and conduction are the remaining modes
of heat transfer that need to be reduced to ensure best thermal
performance, i.e., high thermal resistance (R-value). Some studies
have shown that if convection is minimized, infrared radiation can
account for about 30 to 40% of the heat flow through a fibrous
insulation product. The remaining portion of the heat flow would
then be due to still air and solid material conduction. From a
physics standpoint, a fibrous insulation product with fine fiber
has more surface area per mass of fiberized material to intercept
and scatter infrared thermal radiation versus a product with
coarser fiber diameter. This is especially effective if the
chemistry of the fiber enhances the scattering and absorption of
the radiation. For glass fibers, having 8% or higher concentrations
of B.sub.2O.sub.3 in the glass chemistry greatly enhances the
scattering and absorption of infrared thermal radiation. Surface
coatings can also be applied to fibers to enhance scattering and
absorption. A network of fine fiber is also more effective in
creating pockets of still air and minimizing sold conduction
through the individual fibers. The combination of improved
radiation scattering, minimal air movement and minimized sold
conduction produces very good thermal performance. An additional
benefit of fine fiber is that the material can be installed at low
densities to achieve standard R-value requirements, e.g., R-13 @
0.8 to 1.0 PCF installed density or R-15 @ 1.5 to 1.8 PCF in a
standard 2.times.4, 8' high, 16'' on center cavity.
[0032] The nodules of fibrous insulation for use in the present
invention are made with conventional hammer mills, slicer-dicers or
equivalent material processing machines. A slicer-dicer cuts or
shears blankets, a layer, of fiberglass insulation into small
cube-like or other three dimensional pieces. Hammer mills and the
like tear and shear virgin fiber glass or fiber glass blanket and
tend to roll them into generally irregular spherical or rounded
nodules, keeping most pieces in the mill until they achieve a
pre-selected size. The nodule size is controlled using an exit
screen containing the appropriate opening size to produce the
desired nodule size. Any type of fiberglass insulation product can
be processed in a hammer mill, i.e. blanket in which the glass
fibers are bonded together with a cured resin, usually a thermoset
resin, or a blanket of virgin fiberglass containing only de-dusting
oil, silicone anti-stat, etc. Also, the binder used to bond the
glass fibers together in the blanket can also contain one or more
of functional ingredients such as IR barrier agents, anti-static
agents, anti-fungal agents, biocides, de-dusting agents, pigments
colorants, microencapsulated phase change material (such as
Micronal.TM. PCM from BASF), etc., or one or more of these
functional ingredients can be applied to the fibers either before
or during processing in the hammer mill or other reducing
device.
[0033] The size of openings in an exit screen in the hammer mill or
similar device are varied to produce the desired nodule size. The
preferred size depends on the cutting and shearing characteristics
of the fibrous material. For fiberglass material, an exit screen
size with square openings ranging from 1 to 3 inches can be used to
produce nodule or clump sizes that range in size from 1/8 inch to
3/4 inch. The preferred screen size used to make the nodules making
up the insulation product of the invention preferably has a
continual pattern of 2 inch.times.2 inch squares or 2 inch diameter
holes. This 2 inch screen opening size produces nodules of 1/4 inch
or smaller size range.
[0034] The nodules of inorganic fiber such as fiberglass can also
be made from what is called "virgin blowing wool". Virgin blowing
wool is made by making glass fiber insulation in a conventional
manner except that one or more dry, but water or liquid
activatable, water based adhesive or hot melt adhesive is applied
to the fibers. In addition, a de-dusting oil and/or an anti-stat
like silicone is applied to the fibers and the resultant fibrous
blanket is then run through the hammer mill or similar processing
device. The water based or hot melt reactivatable adhesive and
other agents can also be applied to the fibers such as a fungicide,
a biocide, filler particles and/or IR retarding additives, either
soon before or immediately before blowing through a nozzle or end
of a hose, or earlier in the hammer mill or other nodulating
machine. Although the activatable adhesive or binder can be
dispersed throughout the nodules, it is desirable to have the
adhesive or binder concentrated at the surface of the nodules.
[0035] The inorganic fibers used in the present invention can be
glass, mineral wool, slag wool, or a ceramic fiber and preferably
is fiberglass. Inorganic fibrous material has low moisture sorption
(absorption and adsorption) potential, typically less the 5%
moisture gain by weight. The application of fiber surface
waterproofing agents, such as silicone or de-dusting oils can
further reduce moisture sorption potential. A material with low
moisture sorption is preferred for spray-applied application to
allow for fast drying and to limit moisture storage capacity, which
greatly limits the potential for mold growth.
[0036] The particles or nodules of the present invention are
smaller and greater in number than used before as a blown in
insulation product. Nodules are defined as very small diameter
generally spherical, but having one or more radii, fibrous
insulation of 1/4 inch and smaller as described in the Summary.
Having a small nodule size is important to achieve good installed
thermal performance. With a small nodule size, the material will
effectively fill around obstructions in building cavities such as
electrical boxes, wiring and plumbing, thus, providing a uniform
void-free fill. A small nodule size also allows the installer to
maintain surface flatness and uniformity in the insulation product
after excess material is removed from the cavity framing faces.
Additional benefits from having small nodule size are reduced
plugging potential as the material flows through the components of
the blowing equipment, reduced potential for gaps and bridging
voids along the framing members and elsewhere, more consistent
R-values, improved air flow resistance and better wetting
characteristics when adhesive is applied. The nodules of the
present invention are smaller and greater in number than heretofore
coated with water containing a water soluble adhesive and used to
make a blown in insulation product.
[0037] In the invention the just installed insulation is obtained
with nodules of insulation that are coated with a reactivatable,
remoistenable adhesive. Production of the small coated nodules that
make up the insulation product can be produced as shown in FIGS. 2
and 3. Inorganic fibers of the type described above can be made by
any one of a plethora of fiber making systems 10 and any of the
fibers meeting the above description are usable in the invention.
The systems 10 produce virgin inorganic fibers 16 that can either
be sent directly to a nodulating machine like a hammer mill, first
coated with dedusting oil and/or other additives in an intermediate
step 24 or first sprayed with a binder step 26, submitted to a
drying and curing step 28, and a trimming or scrapping step 30 and
then sent to the nodulating machine, such as hammer mill 18. The
nodulating machine, such as a hammer mill 18 having an exit screen
having appropriate hole sizes therein produces nodules of the
desired size described above. The exiting nodules 32 are then
coated with a reactivatable adhesive in a coating step 34,
optionally dried or cooled in step 36 to set the adhesive coating
on the surface of the nodules 32 to produce coated nodules 38. The
reactivatable adhesive is predominately on the outer surface of the
nodules.
[0038] Applying a reactivatable adhesive to the nodules 32 can be
done by any of a number of alternative ways. If the reactivatable
adhesive desired is available as a dry powder, the powder can be
applied to the surfaces of the insulation nodules 32 by either
blowing or mechanically slinging the powder onto the nodules 32
while they are falling through the air or are being tumbled or
suspended in a mixer or insulation blowing machine. The dry powder
particles attach to the surface portion of the nodules 32 by
lodging in the openings between the fibers and by attaching to the
fibers with static forces. Spraying the reactivatable adhesive in
the form of a aqueous or solvent solution or suspension or a molten
hot melt onto the nodules 32 as they fall past spray heads works
better. When the reactivatable adhesive is water based it must be
thoroughly dried before the coated insulation nodules are packaged
to prevent their sticking together too tightly in the packages.
This can be accomplished with a counter flow of hot air at a
temperature sufficient to rapidly dry the coated nodules without
deteriorating the adhesive. When the adhesive is applied as a
molten hot melt, the coated nodules need to be cooled cooled
sufficiently to solidify the adhesive before the nodules are
collected together. The nodules 38 coated with a reactivatable
adhesive can then go to a hopper above an insulating blowing
machine or directly to the insulating blowing machine 2, or to
packaging equipment 40.
[0039] There are many alternative ways to produce the reactivatable
adhesive coated nodules. One alternative way is to feed, or dump
bags or bales of compressed, loose-fill nodules of inorganic fiber
loose-fill insulation made as described above into a hopper or
mixer similar to conventional blowing machines. Reactivatable or
remoistenable adhesives are sprayed or otherwise introduced into
the hopper or mixer and the mixture is tumbled and then dried to
produce fibrous nodules coated with the reactivatable adhesive.
Spray applied reactivatable or remoistenable hot melt adhesives are
desirable because there is no water to dry out--cool air sprayed
onto the nodules will solidify the hot melt remoistenable adhesive
very quickly leaving most of the adhesive on the outer surface of
the nodules where it is most needed and where, upon remoistening,
it produces the most tackiness for the nodules to stick together in
the building cavity. Hot melt adhesive spray equipment is well
known and readily available from a number of sources.
[0040] Reactivatable or remoistenable adhesives are typically
applied to stamps, tapes, labels, envelopes, etc., during their
manufacture to facilitate subsequent application and/or closure of
those products. H.B. Fuller offers both water-based and hot melt
remoistenable adhesives for a variety of application and
performance requirements. Typical of some of the remoistenable hot
melt adhesives are disclosed in U.S. Pat. No. 5,459,184, the
disclosure of which is herein incorporated by reference. Specific
product examples from other suppliers like DynaTech Adhesives
include water based products like FlexTac.TM. 272 and 7465.
[0041] Hot melt remoistenable adhesives can be applied to the
surfaces of the nodules in the form of particles, molten droplets
or a molten fine fibrous web, the latter by using conventional hot
melt spray nozzles and other spray, feeder, spreader or slining
equipment. For example, hot melt remoistenable adhesives can be
melted using a Nordson Series 3500 melt tank, the melted adhesive
can then be pumped to a bank of Nordson Universal CF spray nozzles
or other nozzles such as ITW Dynatec Laminated Plate Technology
[0042] Following drying and/or cooling, the nodules coated with a
reactivatable, remoistenable adhesive are packaged in bags, barrels
or boxes. The coated nodules need to be packaged such that the
package prevents moisture or high humidity from penetrating the
packaging material and activating the adhesive coating on the
surface of the coated nodules that would cause the nodules to bond
together forming one or more lumps of bonded together compressed
nodules. Packaging materials, normally plastic, are well known for
this purpose. The barrier material can be only a plastic bag or
plastic drum, or a plastic bag inside another container such as
Kraft boxes, bags or drums.
[0043] The resultant coated nodules of inorganic fiber insulation
contain, also in an outer region of the nodules an amount of resin
or adhesive content of less than about 10 wt. percent, based on the
dry weight of the nodules, more typically less than about 4-5 wt.
percent and most typically less than about 2 wt. percent for
installed densities ranging from about 0.8 to about 2-3 PCF.
[0044] Some methods of making coated insulation nodules of the
invention are illustrated in FIG. 3. Fibrous insulation nodules 32
are made in a nodulating machine such as a hammer mill 18. The
insulation nodules 32 can be collected in any suitable manner such
as with a belt conveyor 42, or can be dropped directly through a
coating zone 44. In the coating zone 44, the insulation nodules 32
are coated with a reactivatable adhesive using either one or more
banks of heated nozzles 46 spraying molten hot melt reactivatable
adhesive from a heated hot melt tank 45 and a pump 47 via a heated
line 48, or with a reactivatable adhesive in solution or suspension
in a liquid such as water or solvent using one or more banks of
spray jets 50 being fed with the solution or suspension from a
holding tank 52, pump 53, and line 54.
[0045] The coated insulation nodules 55 continue to free fall
through a chamber 56 where they encounter a counter flow of hot,
drying air, or when the reactivatable adhesive is a molten hot
melt, cooling air, supplied by a manifold 59 surrounding the
chamber 56 and communicating with the interior of the chamber 56
via a continuous or interrupted circumferential slot or a plurality
of spaced apart hollow conduits. A stream of hot or cool air 60 is
supplied to the manifold 59 in known manner. The resultant hot, or
cool, reactivatable adhesive coated insulation nodules 62 of the
invention continue to fall into a collection chamber 64. When the
coated nodules 62 are hot, they can optionally be cooled by a flow
of cool air 66 via a manifold 65 surrounding a lower portion the
collection chamber 64. One or more agitator/feeders 67 in the
bottom of the collection chamber 64 feed the coated nodules 62 at a
desired rate into either conventional packaging equipment (not
shown) to produce sealed packages 68 of compressed, coated nodules
62 of the invention, or into an insulation blowing machine.
[0046] As shown in FIG. 4, nodules of inorganic fibrous insulation,
made by nodulating either virgin fiber or fiber bonded with a dried
and cured resin in the form of trim or scrap, or a mixture thereof,
is fed into a nodulating machine such as a hammer mill 18
containing an exit screen to produce nodules 32 having a diameter
of less than about 1/2 inch are fed either directly or indirectly
into an insulation blowing machine 2. These nodules can be first
fed into packaging equipment 40 to produce packages 41 of
compressed nodules 32. The nodules are suspended in air and blown
through a hose 6 and as they exit the hose 6, or an optional nozzle
5, are spray coated with sprays 51, coming from spray jets 50, of
reactivatable adhesive in the form of either a molten hot melt or a
solution or a liquid suspension of reactivatable adhesive
particles. The coated nodules 55 are then allowed to drop through a
chamber 56 against a counter flow 58 of either hot air to dry the
coating or a cool air to solidify the coating. The dried and/or
cooled coated nodules 62 are then collected in a hopper 64 and,
with an agitating feeder 67, are fed into packaging equipment 40
that compresses the coated nodules 62 in moisture proof bags, boxes
or drums for storage or shipment to a building job site.
EXAMPLE 1
[0047] Virgin glass fiber having an average fiber diameter of 2
microns and made by a conventional process such as described in
U.S. Pat. No. 4,058,386, is fed to a hammer mill containing an exit
screen having hole diameters sized to produce nodules of one half
inch and smaller diameters. These nodules are allowed to fall in
front of a bank of hot melt adhesive spray heads spraying H.B.
Fuller Co.'s NP 2255 remoistenable hot melt adhesive to coat the
nodules. The remoistenable hot melt is applied to the falling
nodules in a process like that illustrated in FIG. 3 using a bank
of 20 ITW spray heads, each equipped with #109448 nozzles and 20
psi compressed air, delivering, for example, about 150 grams per
minute of fiberized H.B. Fuller's NP 2255 hot melt across a 22-24
inch wide flow of falling nodules. Counter flow of cool air in a
chamber beneath the spray zone rapidly solidifies the hot melt web
on the surface of the fibrous insulation nodules to produce
reactivatable coated fiberous insulation nodules.
EXAMPLE 2
[0048] A moisture activated envelope flap type adhesive such as
Dyna-Tech.TM. Flextac.TM. 272 or 7465 is spray applied to
fiberglass nodules like those described in Example 1. These
adhesives are water based and are pumped to spray jets with a pump
as shown in FIG. 3. The adhesives have solids contents of 55% or
more, therefore the coated nodules dry very fast when sprayed onto
hot nodules, or when the coated nodules are subjected to a counter
flow of hot air, to produce reactivatable adhesive coated
insulation nodules.
EXAMPLE 3
[0049] As shown in FIG. 4, nodules of inorganic fibrous insulation,
either virgin fiber or fiber bonded with a dried and cured resin in
the form of trim or scrap, are fed into a nodulating machine such
as a hammer mill containing an exit screen to produce fibrous
insulation nodules having a diameter of less than about 1/2 inch.
These nodules are then either fed into packaging equipment or
directly into an insulation blowing machine. The nodules are
suspended in air and blown through a hose. As they exit the hose,
or an optional nozzle, the nozzles are spray coated with sprays of
reactivatable adhesive in the form of either a molten hot melt or a
solution or a liquid suspension of reactivatable adhesive particles
as described in Examples 1 and 2. The coated nodules are then
allowed to drop through a chamber against a counter flow of either
hot air to dry the coating or a cool air to solidify the coating.
The coated nodules are then collected and fed into packaging
equipment that compresses the coated nodules in moisture proof
bags, boxes, or drums, for storage or shipment to a building job
site.
EXAMPLE 4
[0050] A Unisul Volumatic.RTM. III insulation blowing machine
equipped with 150 feet of 4 inch diameter hose is used to produce
an insulation mass flow rate of approximately 18 lbs/minute of the
reactivatable adhesive coated insulation nodules of Examples 1, 2,
and 3, each comprising glass fibers having an average fiber
diameter of 2 microns and an average nodule diameter in the range
of about 0.25 to about 0.6 inch. The glass fiber in the nodules
contains an average boron oxide content of about 8.7 wt.
percent.
[0051] The blowing machine is operated with the transmission in 3rd
gear, with 100% of the available blower air delivered to the rotary
airlock assembly and with the slide gate (feed gate) set at 12
inches. The blower and secondary gearbox speeds (RPM settings) on
the blowing machine are set to the manufacturer's recommended
settings of 1425 and 1050 rpm, respectively. The mass flow of
insulation is allowed to freely flow through the blowing hose into
a nozzle at the end of the blowing hose. Spray jets on the outside
of the nozzle are used to spray water to the mass flow of coated
nodule insulation as the coated nodules exit from the nozzle. The
water is applied at a rate of about 0.25 gallons/minute with the
use of a Spray Tech pump (model 0295003). The spray nozzle assembly
consists of a 4 inch diameter tube, the end of which is surrounded
by an annular manifold containing two Spray System Co. model
TPU-65-015 spray tips screwed into threaded ports located 180
degrees apart on the manifold. The ports are set at a 30 degree
angle to the centerline of the mass insulation flow direction. This
allows the water to be sprayed and entrained into the mass flow of
coated nodules without disrupting the flow characteristics of the
nodules to provide an insulation to water ratio in the just
installed product of about 9:1.
[0052] By moving the nozzle from bottom to top and with a side to
side motion from the bottom of the cavity to the top, the wetted,
activated coated nodules of insulation is directed into various 8
foot high cavities defined between 8 foot high vertical 2.times.4's
or 2.times.6's spaced on 16 inch centers or 24 inch centers to
achieve a consistent fill with about 2-3 inches of excess
insulation material extending beyond faces of each vertical framing
member. Standard SPF wood framing (2.times.4 or 2.times.6) is used
to form the cavities of the test walls. Oriented Strand Board (OSB)
sheathing is used as the back wall of each cavity. The spray nozzle
is held approximately 6 feet away from the open cavity during the
installation process. Shortly after installation, the excess
material is removed with the use of a commercial rotary wall
scrubber (Krendl.TM. model 349B). The removed excess material is
vacuumed up using a 50 foot length of 4 inch diameter hose
connected to a centrifugal vacuum fan (Wm. W. Meyer & Sons,
Inc. Versa-Vac (11) for recycling. At this flow rate, installation
times of about 10 to about 15 seconds are required to fill a
standard cavity. This is a much shorter application time than
heretofore possible with prior art products.
[0053] Using the described equipment set up, the just installed
moisture content of the insulation in each test wall is about 10-15
wt.% on an oven dry mass basis. Measurement is accomplished with
the use of a load cell connected to a chain hoist. A large oven is
used to dry the samples after the initial weights are taken. Over
the 10-15% range, approximately 0.25 to 0.35 lbs of water exists in
a standard 8 foot high, 16 inch on center 2.times.4 wall cavity.
The oven dry density of the installed material is in the range from
0.9 to 1.1 PCF. Thermal testing on various samples in this same
density range shows that the material provides an R-13 level of
insulation in a standard 2.times.4 cavity. Loss On Ignition (LOI)
testing indicates that approximately 2 to 3% adhesive solids exists
in the installed material. With this content of adhesive solids, no
problems are encountered with any installed material falling out of
the wall cavities or with any post-installation settling or fallout
in both 2.times.4 and 2.times.6 cavities. As the installed
insulation dries, the adhesive provides still further bond strength
and integrity in the insulation. The present invention, in
applications at the lowest densities disclosed, will exhibit
sufficient integrity to resist settling, shrinkage, or collapse in
the cavity, even at a depth of 6 inches or more.
[0054] At a distance 6 foot from the cavity face densities in a
range from 0.8 to 1.2 PCF can be consistently obtained. At 4 feet
away, densities ranging from 1.3 to 1.5 PCF can be obtained and at
2 feet away, densities ranging from 1.6 to 1.9 PCF are achieveable.
This ability to vary the installed density allows respective
R-values of R-13, R-14 and R-15 to be obtained in standard
2.times.4 cavities. The results of this Example are found in Tables
1 and 2 below.
TABLE-US-00001 TABLE 1 Low Density Installation (nozzle position 6
feet from wall) 2 .times. 4, 2 .times. 4 2 .times. 6, 16'' O.C.
24'' O.C. 16'' O.C. 2 .times. 6, 24'' O.C. Installed 10 15 10 15 10
15 10 15 Moisture, % Installed Water 0.25 0.35 0.4 0.55 0.4 0.55
0.6 0.9 Weight, lbs/cav. Installation Time, 10 15 15 24
seconds/cavity Dry Insulation 0.8 0.9 0.8 0.9 0.8 0.9 0.8 0.9
Density, PCF R-value 13 13 20 20
The water spray onto the coated nodules and the dry coated nodules
coming to the nozzle, i.e. ratio of mass flow of liquid to mass
flow of dry nodules.
TABLE-US-00002 [0055] TABLE 2 High Density Installation (nozzle
position about 2 feet from cavity back wall) 2 .times. 4, 2 .times.
6, 2 .times. 6, 16'' O.C. 2 .times. 4 24'' O.C. 16'' O.C. 24'' O.C.
Installed 10 15 10 15 10 15 10 15 Moisture, % Installed Water 0.5
0.75 0.75 1.1 0.75 1.1 1.2 1.8 Weight, lbs/cav. Installation Time,
21 32 33 51 seconds/cavity Dry Insulation 1.7 1.8 1.7 1.8 1.7 1.8
1.7 1.8 Density, pcf R-value 15 15 23 23
[0056] In addition to the equipment set up previously described,
numerous other combinations of pump flow rates, adhesive to water
ratios, spray nozzle configurations, blowing machine settings,
blowing machine types, adhesives and installation techniques can be
used to achieve similar installed densities and similar or lower
moisture levels. The particular settings described above primarily
resulted from conducting a series of designed experiments to
identify optimal settings that would deliver desired installation
and performance characteristics of insulation material similar to
that disclosed herein. The above results are demonstrative of the
very low installed density, the very low installed cavity moisture
weight and the very fast installation that is achievable with the
present invention in comparison to the prior art. Installed
moisture levels as low as about 2% can be obtained, but at some
expense of other desired characteristics such as installation time
and/or adhesive cost.
[0057] When filling wall cavities with sprayed-on insulation it is
necessary to spray an excess of insulation nodules to make sure
each cavity is fully filled. This requires that the excess
insulation be either removed, or compressed to be even with the
face of the studs after spraying and before the adhesive coating on
the clumps or nodules dries to enable wall board, or other facing
board to lie flush on the faces of the studs. As confirmed in U.S.
Pat. No. 5,641,368, it has been found that a powered scrubber
conventionally used to remove excess thickness of sprayed
insulation will not work with conventional sprayed-on loose-fill
fiberglass insulation because the powered reverse rotating action
of the scrubber often tears large chunks of the fiberglass from the
cavity. A scrubber is a rotating brush-like device that is long
enough to span two adjacent studs. Although called a scrubber,
water or other liquid is not involved in its use.
[0058] The use of a scrubber with the product of the present
invention would not result in the reported problem. Because of the
higher tackiness and small size of the nodules that form the
insulation product of this invention, and the absence of voids
caused by bridging, a scrubber is perfectly acceptable for removing
excess insulation. Scrubbers do not tend to tear out large chunks
from the insulation between the studs. It is not necessary to roll
the just installed insulation of the present invention to reduce
the thickness to the desired amount and preferably it is not rolled
or compressed by any other means. These same features minimize
slumping and collapse of the insulation during formation.
Preferably, any excess thickness is removed using a scrubber or
other functionally equivalent means.
[0059] As confirmed in the just above mentioned patent and others,
it has been found in the past that excess adhesive was required to
coat clumps of fiberglass containing a silicone, but an additional
aspect of the present invention is that the clumps and/or nodules
of insulation can contain silicone which is desirable for the
waterproofing function that the silicone conventionally
produces.
[0060] Biocide and/or desiccant agents can be added to the material
during manufacturing or during installation to provide additional
protection against potential mold growth and to potentially protect
adjacent substrate materials (framing, sheathing, etc.) from
potential mold growth.
[0061] With some or all of these unique attributes, a uniform
cavity fill can be obtained over a wide range of installed R-values
at low installed densities, having low moisture contents for fast
drying. Mold growth potential is minimized by keeping the installed
density low and the material cost is kept to a minimum.
[0062] Several examples and ranges of parameters of preferred
embodiments of the present invention are described above, but it
will be apparent to those of ordinary skill in the insulation field
that many other embodiments may be possible by manipulation of the
parameters of the invention. For example, although only a few
different reactivatable adhesives are specifically disclosed, there
are other suitable adhesives that will function in the same or very
similar manner as in the above disclosed invention to produce the
useful result of having high tack value. While most of the above
discussion involves using the present invention in generally
vertical wall cavities, this insulation product can also be used to
insulate attics, ceilings, undersides or sloping roofs or any area
that can be reached with a spray of the activated, air suspended
nodule product.
* * * * *