Note: Descriptions are shown in the official language in which they were submitted.
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FACER AND CONSTRUCTION MATERIALS MADE THEREWITH
Background of the Invention
Rigid polymeric foam insulation laminates have been used in the construction
industry for many years. For instance, they have been widely used as
commercial roof
insulation boards which are employed under asphaltic built-up roof (BUR)
membranes as
well as under various single ply membranes, such as EPDM rubber, polyvinyl
chloride
(PVC), modified bitumen membranes, thermoplastic polyolefins (TPO's), and the
like.
Other uses for such rigid polymeric foam insulation laminates include
residential insulation,
sheathing under siding, and roof insulation under asphalt shingles and
concrete tiles.
Such insulation often takes the form of a core polymeric foamed thermoset
material,
such as a polyurethane, a polyisocyanurate, a polyurethane modified
polyisocyanurate (often
referred to as polyiso) or a phenolic resin, applied between two facing
sheets.
Insulation boards are generally manufactured on production lines where a
liquid core
chemical mixture is poured over a bottom facer, foaming up to contact a top
facer in a
constrained rise laminator. The reaction of the chemical mixture causing
foaming is
generally exothermic, as curing via polymerization and crosslinking occurs in
the laminator.
In the case of polyisocyanurate insulation boards, the curing exotherm lasts
well into the
time the resulting rigid boards are cut, stacked and warehoused. The exotherm
can continue
for as long as 4 days and the mixture can reach temperatures as high as 325 F
(163 C).
Desirable properties for the facers include flexibility, high tensile
strength, high tear
strength, and resistance to thermal degradation. Facer porosity should be low
and the
thickness of the facer coating should be sufficient to prevent bleed-through
of liquid
chemicals prior to foaming. Additionally, facers should exhibit good adhesion
to the core
foam insulation and be inert to the effects of extraneous chemicals which may
be present in
the mixture, especially blowing agents that also behave as solvents. Blowing
agents
currently in use include chlorofluorocarbons such as I-ICFC-141b and R-22 as
well as
hydrocarbons, such as n-pentane, cyclo-pentane and iso-pentane.
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One problem that has plagued the polyiso industry has been a phenomenon called
"cold temperature delamination". This phenomenon occurs in cold temperature
areas where
insulation boards coming off the production line cool before they can be
"stack cured". In a
worst case scenario; the polyiso core foam layer closest to the facer cools,
quenching the
cure reaction and leaving a brittle layer. This often leads to shearing of the
core layer or
facer peel off. It has been the practice of manufacturers to place a layer of
corrugated
cardboard over both the top facer surface of the top board and under the
bottom facer
surface of the bottom board in the stack, to retain exothermic heat and
prevent subsequent
delamination. Thus, a facer that inherently insulates and retains heat during
stack cure
would materially reduce incidents of cold temperature delamination and would
eliminate the
need for costly cardboard insulation.
After foamed polymer insulation boards are cured, cut and shipped to their use
site,
the facer should provide mechanical stability as well as water and weather
resistance since,
upon installation, they may be exposed to persistent rain, high humidity,
ultraviolet light and
excessive heat. Additionally, the facers must be puncture and scuff resistant
to survive
being fastened, e.g., by screws or nails, and walked on. Withstanding
temperatures up to
500 F (260 C), as encountered in hot asphalt applications, as well as
resistance to the
deleterious effects of adhesive solvents used in single ply and cold applied
roofing
membrane applications while strongly bonding to the adhesives themselves are
also
important facer properties.
Traditionally, facer materials have included asphalt saturated cellulosic
felts,
fiberglass mats, asphalt emulsion coated fiberglass mats, aluminum
foil/lCraftifoil, glass
fiber modified cellulosic felts, glass mats onto which polymeric films have
been extruded,
and glass mats coated with polymeric latex/inorganic binder coatings. However,
all of these
materials have at least one undesirable property. For example, asphalt-
containing products
are not compatible with PVC single ply roofing membranes. Fiberglass mats are
subject to
excessive bleed-through of foamable core chemicals. Aluminum facers and foils
reflect heat
into the foam during processing which leads to disruption of cell structure,
delamination and
warping. Further, foil faced sheathing and extrusion or lamination of a
polymer film to glass
mat surfaces are costly. Specifically, glass mats coated with polymer
latex/inorganic binder
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mixtures have been found to be brittle; conversely, glass fiber modified
cellulosic felts are
susceptible to moisture absorption aggravating board warping in damp or wet
environments.
Other facers which have been employed for siding underlayment and insulation
board facers include those disclosed in United States Patent 5,776,841 and
United States
Patent 5,717,012, which are primarily felts. United States Patent 5,776,841
concerns a light
weight sheet felt material suitable for use as roof and siding underlayment
and insulation
board facing which comprises on a dry basis (a) 60-80 weight percent cellulose
fibers; (b)
15-30 weight percent glass fibers having a diameter of 5 to 16 microns and a
length of 3/8-
314 inch (9.5 nun to 19.1 mm); (c) 4-10 weight percent binder and (d) 0.5-10
weight percent
non-asphaltic, sizing agent having a flash point above 150 F (66 C) and an
evaporation rate
less than one which is selected from the group consisting of anionic rosinous
and
amphipathic ester and anhydride sizes and mixtures thereof. The felt of United
States Patent
5,776,841 is of considerably lighter weight and higher porosity than other
felting materials
used for the same purpose and can be supplied in longer continuous sheet rolls
than
heretofore practical from a standpoint of handling, shipping, storage, and
installation. Also
the sheet felt of United States Patent 5,776,841 can be produced on
conventional felt making
equipment in a one step process.
United States Patent 5,001,005 describes a facing sheet composed of glass
fibers and
a non-asphaltic binder. The facer of United States Patent 5,001,005 contains
60 percent to
90 percent glass fibers, which high fiber content does not provide sufficient
binder to close
the sheet's pores or to provide desired sheet strength. United States Patent
5,102,728
describes a glass mat substrate coated with a polymeric latex blended with an
asphalt
emulsion, concerns a product which is not only incompatible with PVC roofing
membranes
but also requires excessive coating thicknesses to reduce high porosity.
Accordingly, this
product is very costly. United States Patent 5,112,678 discloses a facer
prepared by
applying to a fiberglass mat a fiowable polymer latex and an inorganic binder
coating. The
resulting product is somewhat brittle and is susceptible to an undesirable
degree of chemical
bleed through. 'United States Patent 5,698,302 and United States Patent
5,698,304 describe
facers where polymer films are laminated or extruded onto fiberglass mat. Not
only is this
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approach costly, but also since conventional mineral flame retardant filled
polymers do not
extrude well, some degree of resistance to flammability must be sacrificed.
United States Patent 6,365,533, United States Patent 6,368,991, and United
States
Patent 6,774,071 describe a low fiber, plyable facer suitable for use in the
construction
industry, particularly for insulation board manufacture, comprising a dry
preformed fiber
mat containing a binder for the fibers, preferably a preformed glass mat,
coated with a
prefoamed composition which contains a polymer latex, a foam sustaining amount
of a
surfactant and a flame retarding and/or strengthening amount of a mineral
filler and also to
the use and process for the preparation of the above as well as to a siding
uriderlayment or
insulation board having a foamed, thermosetting resin core which is surfaced
with said facer
as a product for commercial use. These patents further describe a dry flexible
facer
comprising a non-asphaltic, non-cellulosic fiber mat surfaced with a cured
foam comprising
(a) between about 15 and about 80 weight percent of a polymer latex, (b)
between about
0.01 and about 80 weight percent of a mineral filler and (c) between about 0.5
and about 10
weight percent of a foam supporting surfactant, and (d) between about 0.01 and
about 5
weight percent of a catalyst.
Gypsum construction boards are widely used in building construction. Gypsum
construction boards typically include a set gypsum core that is sandwiched
between two
facers. However, in some cases the gypsum core has a facer that is affixed to
only one of its
two sides.
United States Patent Application Publication 2005/0203205 discloses a
composition
of matter incorporating nanotechnology with UV curable materials for the
coating of
fiberglass. This patent publication more specifically discloses a one-part,
substantially
solvent-free coating composition for applying to fiberglass substrates,
consisting essentially
.. of: a polyrnerizable compound which comprises a mixture of acrylates,
photoinitiator or a
photoinitiator mix, silicon dioxide monospheres, and surfactant or mixture of
surfactants.
United States Patent Application Publication 2005/0203205 further reveals a
composition of
matter comprising UV curable materials incorporating nanotechnology for the
coating of
fiberglass This patent publication further discloses a one-part, substantially
solvent-five
coating composition for applying to a substrate, consisting essentially of:
from about 60
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percent to 80 percent by weight, based on total composition weight, of a
polymerizable
compound which comprises a mixture of acrylates, the acrylate mixture
comprising an
aliphatic urethane acrylate and a mixture of acrylate monomers, from 10
percent to 30
percent silicon dioxide monospheres of a diameter of approximately 20
nanorneters, and
from about 1 percent to 10 percent of an organic photoinitiator which
initiates a
polymerization reaction in the composition when it is exposed to ultraviolet
light, without
the use of added heat for either evaporation or postcure.
Summary of the Invention
It is an object of this invention to overcome the above described
disadvantages and
deficiencies of prior art facers and to provide a facer which is economically
produced by a
commercially feasible process. It is also an object of this invention to
provide a
mechanically stable facer suitable for insulation board manufacture which
resists cold
temperature delamination and which has superior tolerance to the effects of
weathering. It is
another object of this invention to provide a facer which exhibits superior
adhesion to
polyiso foam of an insulation board core material. These and other objects and
advantages
of the invention will become apparent from the following description and
disclosure.
This invention relates to facers used for the production of construction
materials,
such as insulation and other construction boards. Such boards can be composed,
in part, of
foam insulation, such as but not limited to, polyurethane, polyurethane-
polyisocyanurate
hybrid, polyphenolic, expanded polystyrene, extruded polystyrene, and
polyisocynurate.
Such boards can also be composed of gypsum, cement or concrete, mineral fiber,
fiberglass,
wood, cellulose or any other board used in structural and non-structural
building materials.
The facer of this invention also can be used as or in conjunction with
underlayments or
siding used in buildings.
Insulation boards made from polyurethane, poly-urethane-polyisocyanurate
hybrid,
expanded polystyrene, gypsum and/or other materials with a facer on one or
both sides of
the core are well known in building industry. Historically, paper based facers
have been
used to make these boards. However, more recently fiberglass-mat based facers
have been
used in the industry. Fiberglass-mat based facers have been produced by
coating glass-mat
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with water-based coatings and are considered to have good dimensionally
stability, fungal
resistance and other advantages. Such glass-mat based facers produced from
water-based
coatings also have certain disadvantages. The invention produces a better
facer with some
or all of the following advantages over facers made by applying water or
solvent based
coatings on glass-mat: (1) environmentally friendly, (2) lower energy costs,
(3) excellent
water, chemical, and stain resistance, (4) excellent abrasion, scratch, and
scuff resistance, (5)
good exterior durability, (6) smaller production space, (7) increased
productivity, (8)
potentially lower applied coating costs, (9) temperature resistance, and (10)
allows for the
utilization of heat sensitive substrates.
This invention calls for application of electron beam or ultraviolet light
curable
resin-based coating compound on a substrate like fiberglass-mat, polyester
fiber mat or other
substrate and cure of the coating by using an electron beam source to develop
facers that can
be used with, but not limited to, foam insulation boards composed in part with
polyurethane,
polyurethane-polyisocyanurate hybrid, polypheno lie, expanded polystyrene,
extruded
polystyrene and/or polyisoeyanurate. The facer of this invention can also be
used for
construction boards composed of gypsum, cement or concrete, mineral fiber,
glass wool,
fiberglass, wood, cellulose or any other material used in structural and non-
structural
building boards. Such construction boards may be rigid, semi-rigid or
flexible.
In the practice of this invention the coating can be applied on one or both
sides of the
said substrates to develop undcrlayments that can be used in roofing, siding,
flooring, walls
and elsewhere in buildings. In one preferred composition, the coating compound
will
include one or more electron beam or ultraviolet curable resins and one or
more
organic/inorganic fillers. It may also include additives such as, but not
limited to, flow and
leveling agents, wetting and dispersing agents, defoamer, pigment, biocide
and/or other
agents known to those skilled in the art.
Preferred electron beam (EB) or ultraviolet (UV) curable resins are composed
of a
mixture of at least one monomer and/or at least one oligomer. The monomer
chemistry will
be based on acrylate and/or methaacrylate or other known monomers and oligomer
chemistry will be based on epoxy acrylate, urethane acrylate, polyester
acrylate or other
known oligomers. Monomer and oligomer chemistries may have a mono, di, tri,
tetra, penta
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or higher functionality. Their backbone chemistry may include, but is not
limited to, an
alkane, ester, ether, aliphatic, aromatic and/or any other chemistry. The
invention provides a
fast curing process and polymerization of reactive molecules is done by the
action of
electron beam or ultraviolet light. This process offers the potential for 100%
reactive
ingredients. The coating compound may be applied on the substrate by spraying,
roll
coating, knife coating, air-knife coating or any other known processes used by
those skilled
in the art.
The coating compound may also be foamed, if required, with air by applying
surfactant chemistries or other blowing agents before applying to the
substrate and blowing
agents may be chemical, physical or a combination of the two. The present
invention also
allows for making facers or underlayments with or without conventional fire
retardants
and/or biocides as well as nanopartiele biocides like nano-silver or other in
coating
formulation. In practicing the process of this invention an electron beam or
ultraviolet light
may be applied to one or both sides of the facer to initiate polymerization of
the
polymers/oligomers in the monomeric composition utilized in manufacturing the
facer.
This invention more specifically discloses a process for manufacturing a
flexible
facer comprising (1) applying a monomeric composition to a fiber mat, wherein
the fiber
mat is a non-asphaltic, non-cellulosic fiber mat, and wherein the monomeric
composition is
comprised of a monomer and a filler, (2) initiating polymerization of the
monomer within
the monomeric composition by exposing the monomeric composition to ultraviolet
light or
an electron beam, and (3) allowing the monomer to polymerized to produce the
flexible
facer.
The present invention further reveals an insulation board having a non-elastic
core
and having at least one surface thereof bonded to an uncoated surface of a
facer, wherein the
facer is made by a process comprising (1) applying a monomeric composition to
a fiber mat,
wherein the fiber mat is a non-asphaltic, non-cellulosic fiber mat, and
wherein the
monomeric composition is comprised of a monomer and a filler, (2) initiating
polymerization of the monomer within the monomeric composition by exposing the
monomeric composition to ultraviolet light or an electron beam, and (3)
allowing the
monomer to polymerized to produce the flexible facer.
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The subject invention also discloses a facer-reinforced gypsum board
comprising a
set gypsum containing core having adhered thereto a facer, wherein the facer
is made by a
process comprising (1) applying a monomeric composition to a fiber mat,
wherein the fiber
mat is a non-asphaltic, non-cellulosic fiber mat, and wherein the monomeric
composition is
comprised of a monomer and a filler, (2) initiating polymerization of the
monomer within
the monomeric composition by exposing the monomeric composition to ultraviolet
light or
an electron beam, and (3) allowing the monomer to polymerized to produce the
flexible
facer.
The present invention further reveals a process of manufacturing a
construction
board which comprises (1) positioning a wet gypsum composition between a first
facer and
a second facer to make a laminated sheet of wet construction board, wherein
the first facer is
made by the process comprising (i) applying a monomeric composition to a fiber
mat,
wherein the fiber mat is a non-asphaltic, non-cellulosic fiber mat, and
wherein the
monomeric composition is comprised of a monomer and a filler, (ii) initiating
polymerization of the monomer within the monomeric composition by exposing the
monomeric composition to ultraviolet light or an electron beam, and (iii)
allowing the
monomer to polymerized to produce the flexible facer, and (2) heating the
laminated sheet
of wet construction board to a temperature which is within the range of 200 F
(93 C) to
700 F (371 C) for a period of time which is sufficient to reduce the moisture
content of the
gypsum to be within the range of 18 to 25 percent. The wet gypsum composition
typically
has a moisture content which is within the range of about 40 percent to about
60 percent.
The laminated sheet of wet construction board is typically heated to a
temperature which is
within the range of 200 F (93 C) to 700 F (371 C).
The subject invention also discloses a construction board which is comprised
of a
rigid sheet and a facer, wherein the facer is bonded to at least one side of
said rigid sheet,
wherein the rigid sheet is comprised of a member selected from the group
consisting of
gypsum, blown polystyrene, and polyisocyanurate, and wherein the facer which
is made by
a process comprising (1) applying a monomeric composition to a fiber mat,
wherein the
fiber mat is a non-asphaltic, non-cellulosic fiber mat, and wherein the
monomeric
composition is comprised of a monomer and a filler, (2) initiating
polymerization of the
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monomer within the monomeric composition by exposing the monomeric composition
to
ultraviolet light or an electron beam, and (3) allowing the monomer to
polymerized to
produce the flexible facer. In most cases the facer will be bonded to both
sided of the rigid
sheet.
Detailed Description of the Invention
The fibers of the mat employed in the process of this invention will typically
be
fibers of glass, polyester, polypropylene,
polyester/polyethylene/teraphthalate copolymers,
hybrid types such as polyethylene/glass fibers and other conventional non-
cellulosic fibers.
Mats having glass fibers in random orientation are preferred for their
resistance to heat
generated during the manufacture of insulation boards and flame resistance in
the finished
product. The fiber mats utilized in the practice of this invention will
typically be a non-
asphaltic, non-cellulosic fiber mat, such as glass mats.
The fibrous mats employed in the practice of this invention, generally are
between
about 10 mils (0.25 mm) and about 40 mits (1 mm) in thickness. The fiber mat
will
typically weigh from 3 g/f12 (106 g1in3 ) to 12 gift' (424 g/m3) before being
coated. The fiber
mat used will more typically weight from 4 g/ft2 ( 141 girril to 9 g/ft2 (318
g/m3 and will
preferable weigh from 5 eft2 (177 g/m 3 ) to 8 g/ff (283 g/m3) before being
coated. It is
preferred for the mats to be comprised of glass fibers that have a diameter
which is within
the range of about 3 microns to about 20 microns and most desirably which is
within the
range of 1 0 microns to 18 microns. The glass fibers will typically be from
about 0.25 inch
(6 nun) to about 1.75 inches (44 mm) in length and will desirably be of 0.75
inch (19 mm)
to 1.5 inches (38 mm) in length.
The fillers useful in the present coating mixture include conventional
inorganic types
such as clays, mica, talc, limestone, kaolin, other stone dusts,
gypsum,aluminum silicate
(e.g. Ecca Tex Tm 561 or KaoplateTM C), flame retardant aluminum trihydrate,
ammonium
sulfamate, antimony oxide, calcium silicate, calcium sulfate, zinc borates.
colemanite, and
mixtures thereof.
The monomer chemistry utilized in the monomeric composition will be based on
acrylate and/or methaacrylate or other known monomers. The oligomer chemistry
utilized
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will typically be an epoxy acrylate, a urethane acrylate, a polyester acrylate
or any other
known oligomer. Some representative examples of suitable monomers include
tetrahydrofuryl acrylate (THFA), N,N-dimethyl acrylamide (DMA), 2-hydroxyethyl
methacrylate (HEMA), and hydroxybutyl acrylate (HBA). Hydroxypropyl acrylate
(HPA),
methacrylates corresponding to the foregoing acrylate compounds, alkoxylated
counterparts
to the foregoing, other acrylates and acrylamides containing reactive hydroxy
groups, and
carbon and nitrogen-substituted analogs of the indicated acrylamides should
also produce
good results. Needless to say, mixtures of two or more of the designated
compounds can be
utilized as the monomer. Oligomers of these monomers can, of course, also be
utilized. For
instance, the monomer/oligomer constituent of the monomeric composition can be
a mixture
of an aliphatic urethane acrylate and various acrylate monomers. Some
representative
examples of acrylate monomers that can be used include isobornyl acrylate,
tetrahydrofurfuryl acrylate, propoxylated glycerol triacrylate, hexandiol
diacrylate,
dipropylene glycol diacrylate, tripropylene glycol diacrylate, neopentyl
glycol propoxylate
diacrylate, trimethylopropane triacrylate, trimethylopropane cthoxylate
triacrylate,
pentaerythritol alkoxylate tetraacrylate, and dimethylopropane tetraacrylate.
Optional ingredients in the monomeric composition include acidic adhesion
promoters (preferably crotonic acid, acrylic acid, methacrylic acid, itaconic
acid, and maleic
acid), normally used in a concentration of about 1.0 weight percent to 5.0
weight percent,
cross-linking agents to adjust hardness (e.g., trimethanolopropane triacrylate
[TMPTA} and
1,6-hexanediol diacrylate [HDDAD, normally used in concentrations of about 1
to 5 weight
percent, and heat and product stabilizers, normally used, alone or together,
in a total
concentration of about 0.1 weight percent to 4 weight percent.
There are two general classes of photoinitiators. These classes of
photoinitiators
include Type I photo initiators (unimolecular photoinitiators) and Type II
photoinitiators
(bymolecular photoinitiators). Type I photoinitiators undergo a unimolecular
bond cleavage
upon irradiation to yield free radicals. Type H photoinitiators undergo a
bimolecular
reaction where the excited state of the photoinitiator interacts with a second
molecule (a
coinitiator) to generate free radicals. Both of these types of photoinitiators
can be used in
used in the monomeric composition utilized in making facers by the process of
this
-11-
invention. Some representative examples of electron transfer photoinitiators
that can be
used include benzophenone, diphenoxy benzophenone, halogenated and amino
functional
benzophenones, fluorenone derivatives, anthraquinone derivatives, zanthone
derivatives,
thioxanthone derivatives, camphorquinone, benzil. Some representative examples
of
photofragmentation photoinitiators that can be used include alkyl ethers of
benzoin, benzyl
dimethyl ketal, 2-hydroxy-2-methylpheno1-1-propanone, 2,2-
diethoxyacetophenone, 2-
benzy1-2-N,N-dimethylamino-1-(4-morpholinophenyl) butanone, halogenated
acctophenone
derivatives, sulfonyl chlorides of aromatic compounds, acylphosphine oxides,
his-
acylphosphine oxides, and benzimidazoles.
Photoinitiators that are suitable for use in the practice of this invention
are
commercially available from a wide variety of suppliers. Some representative
examples of
photoinitiators that are commercially available from SartomerTM include
Esacurelm KB-1 benzyl
dimethyl ketal; Esacure 1001M 14-(4-benzoylphenylsulfanyl)pheny11-2-methyl-2-
(4-
methylphenylsulfonyl)propan- I -one; Esacure KS300 I -hydroxy-cyclohexyl-
phenyl -ketone;
Esacure TPO 2,4,6-trimethylbenzoyldiphenylphosphine oxide; Esacure ERA 2-
ethylhexy1-
4-dimethyl amino benzoate; Esacure KL200 2-hydroxy-2-methyl-l-phenyl-1-
propanone;
benzophenone; Esacure One di functional a-hydroxy ketone; Esacure EDB ethy1-4-
(dimethylamino) benzoate; and Esacure 1TX isopropyl thioxanthone. Some
representative
examples of photoinitiators that are commercially available from Dow
ChemicalTM include
CyracureTm UVI-6992 phosphate-based triarylsulfonium salts and Cyracure
antimonate-
based triarylsulfonium salts. Some representative examples of photoinitiators
that are
commercially available from MayzoTM include Benacure 184 1-hydroxy-eyclohexyl-
phenyl- ketone, Benacure 651 2,2-dimethoxy-1,2-diphenylethan-1 -one, Benacure
BP
benzophenone (diphenyl ketone), and Benacure 1173 2-hydroxy-2-methyl-1-pheny1-
1-
propanone.
In some cases it may be beneficial to utilize a blend of various
photoinitiators to
initiate polymerization to cure the monomeric composition. Some blends of this
type that
are commercially available from Sartomer include: Esacure TZT photoinitiator
blend of
tnmethylbenzophenone and methylbenzophenone, Esacure KIP 150 photoinitiator
blend of
oligo (2-hydroxy-2Mmethyl)-1-4-(1-methylvinyl)phenyl propanone and 2-hydroxy-2-
methyl-
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1-pheny1-1-propanone (polymeric), and Esacure KT046 photoinitiator blend of
phosphine
oxide, trimethylbenzophenone, methylbenzophenone, oligo (2-hydroxy-2-methyl)-1-
4-(1-
metlaylvinyl)phenyl propanone, and 2-hydroxy-2-methyl-1-pheny1-1-propanone
(polymeric).
The monomeric composition used in the practice of this invention will
typically
contain from 5 weight percent to 90 weight percent monomers/oligomers and from
5 to 95
weight percent fillers. In cases where the monomeric composition will be cured
by use of an
electron beam the filler will preferably be present in the monomeric
composition at a level
of 30 weight percent to 85 weight percent with the monomers and/or oligomers
being
present at a level which is within the range of 15 weight percent to 70 weight
percent In
cases where the monomeric composition will be cured by use of an electron beam
the filler
will more preferably be present in the monomeric composition at a level which
is within the
range of 50 weight percent to 80 weight percent with the monomers and/or
oligomers being
present at a level which is within the range of 20 weight percent to 50 weight
percent In
cases where the monomeric composition will be cured by use of ultraviolet
light the filler
will preferably be present in the monomeric composition at a level of 20
weight percent to
80 weight percent with the monomers and/or oligomers being present at a level
which is
within the range of 20 weight percent to 80 weight percent. In cases where the
monomeric
composition will be cured by use of ultraviolet light the filler will more
preferably be
present in the monomeric composition at a level which is within the range of
50 weight
percent to 70 weight percent with the monomers and/or oligomers being present
at a level
which is within the range of 30 weight percent to 50 weight percent.
The monomeric composition used in the practice of this invention will
typically be
void of silicon dioxide rnonosphcres. More specifically, the monomeric
composition will
normally be free of silicon dioxide monospheres having a diameter of
approximately 20
nanometers (within the range of 15 to 25 nanometers).
In one embodiment of this invention a foaming agent is included in the
monomeric
composition to produce a foamed coating structure. Air or some other gas, such
as nitrogen
or carbon dioxide, can also optionally be aerated or blown into the monomeric
composition
to produce a foamed coating structure. A gas can typically be incorporated
into the
monomeric composition by blowing, sparging, or mixing the gas therein with
vigorous
CA 02774509 2012-04-17
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agitation. This can be done in the presence or absence of one or more
conventional blowing
agents and/or foaming agents. In cases where a gas is blown into the monomeric
composition it will be formulated to have a sufficient viscosity to hold
bubbles of the gas
therein until polymerization and/or crosslinking has occurred to produce an
essentially solid
foamed structure. Generally the amount of the gas, such as air, incorporated
into the
monomeric composition will be between about 5 percent and about 90 percent by
volume
for optimal consistency and the resulting foamed mixture will optimally have
bubble
openings that are sufficiently small so as to inhibit liquid bleed through the
mat. More
typically, the amount of gas incorporated into the monomeric composition will
be between
about 20 percent and about 85 percent by volume. It is normally preferred for
the amount of
gas incorporated into the monomeric composition to be within the range of
about 60 percent
and about 80 percent by volume.
In any case, the foamed or un-foamed monomeric composition is applied to the
fiber
mat. The monomeric composition is normally applied onto the fiber mat to a
thickness of
from about 1 mil (0.03 mm) to about 100 mils (2.5 mm), preferably 2 mils (0.05
mm) to 10
mils 0.25 mm). This can be accomplished by coating the preformed mat surface
with the
monomeric composition under ambient conditions using a knife blade, air knife,
roller,
sprayer, or any other convenient method of application. The coating weight of
the
monomeric composition applied to the fiber mat will typically be within the
range of about 2
gift2 (71 g/m3) to about 40 g/ft2 (1413g/m3). The coating weight of the
monomeric
composition applied to the fiber mat will more typically be within the range
of about 3 g/ft2
(106 g/m3)to about 20 g/ft2 (706g/m3) and will preferably be within the range
of 4 g/ft2
(141g/m3)to about 10 g/112 (353 g/m3).
The coated fiber mat is then exposed to ultraviolet light or an electron beam
to
initiate polymerization of the monomers and/or oligomers in the monomeric
composition
that was applied to the fiber mat. In cases where ultraviolet light is
employed as the initiator
a photoinitiator will be included in the monomeric composition that is applied
to the fiber
mat. However, a photoinitiator is not needed in cases where polymerization is
initiated with
an electron beam. This is typically accomplished by passing the coated fiber
mat through a
zone where it is exposed to ultraviolet light or an electron beam. It is
normally
CA 02774509 2012-04-17
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advantageous to do this on a continuous basis. However, the coated fiber mat
can optionally
be exposed to the ultraviolet light or the electron beam on a discontinuous
basis. In any
case, the monomers and/or oligomers polymerize to produce a coated mat having
a thickness
of up to about 100 mils (2.5 mm). The weight of the facers of this invention
can vary from
about 40 g/m2 to about 300 g/m2 and the facer sheet will typically have a
thickness of about
40 mils (1 mm) to about 90 mils (2.3 mm) depending on the preference of the
consumer.
The resulting facer product of this invention is desirably flexible and
possesses low
permability to liquid chemicals. The facers of this invention accordingly can
provide
protection for the cores of insulation boards and construction boards. The
facers of this
invention also provide superior dimensional stability and high tensile
strength.
Applying a film or laminating a layer of impervious resin or polymer over the
surface of the facer to provide a trilayered facer member can provide a
totally liquid
impervious surface on the facer, in special situations where that is a need
for high liquid
barrier resistance. A top seal coat of a non-foamed latex is suitable for this
purpose.
Alternatively, a thermoplastic such as polyethylene powder or unexpanded
polystyrene
beads can be used as a filler and melted at an elevated temperatures to close
substantially all
pores of the pervious coating. Expandable excipients and additives such as
cellulose can
also be used for this purpose; although the use of a seal coat is neither
needed nor
recommended. Other methods for accomplishing the similar purpose include the
use of less
air during foaming, the omission or use of less inorganic filler in the
coating composition,
calendering and/or embossing the foamed or frothed surface by contact with a
hot roller or
platen. A combination of any of the above options can be employed for
specialized
purposes if desired.
The insulation boards, for which the facers of this invention are particularly
suited,
.. comprise conventional thermosetting or thermoplastic foam cores, such as
foamed
polyurethane or polyurethane modified polyisocyanurate or phenol-formaldehyde
cores
disposed between a pair of facer members which are laminated to the core
surfaces. Other
non-elastomeric foamable chemicals, such as polyvinyl chloride, polystyrene,
polyethylene,
polypropylene, and others conventionally employed as core material can also be
employed
CA 02774509 2012-04-17
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as the insulation board core of this invention. Rigid foamed cores of this
type are described,
for example, in United States Patent 4,351,873.
The present facers are also suitable for sheathing generally of a thickness up
to about
1 inch and composed of a non-elastic core material. The use of the facers of
this invention
eliminates the need for expensive foil facings which hold and reflect heat and
often cause
warping and deterioration of wood overlayment. Also, foil and similar facings
are easily
punctured which gives rise to moisture attack.
In the insulation manufacture, a roll of the present foamed facer sheet
product is
passed, with its uncoated fiber surface opposite the core surface, to a
laminating zone. The
board core foam precursor chemical or mixture of chemicals can be poured onto
the non-
coated fiber surface of the facer sheet or the core of the insulation board
can be prefoamed to
a self-sustaining consistency. In one embodiment, a first facer of this
invention, with its
uncoated surface abutting the core, is placed below the core. The fiber
surface of a second
facer is positioned and spaced above the core to allow for core expansion,
e.g. in a
constricted rise laminator, where the assembly undergoes an exothermic
reaction and curing
is initiated or in a free-rise application. During the curing operation the
core material foams
and rises to engage the lower uncoated surface of the second facer. It is to
be understood
that one of the first and second facers can be of the same or of a different
composition than
that of this invention; although it is preferred that both of these facers be
those of the
invention described herein. More specifically, one of the facer sheets may be
selected from
those conventionally employed, such as for example a cellulose or cellulose-
glass hybrid felt
sheet, perlite, aluminum foil, multilaminated sheets of foil and Kraft,
uncoated or coated
fibcr glass mats; although the second facer sheet of the present invention
enhances the
advantages described herein. As the core foam is spread on the fibrous surface
of the first
facer sheet entering the laminator, it undergoes an exothermic reaction which
can attain a
temperature up to about 200 F (93 C). The core foam rises to contact the
undersurfaee of
the second facer and hardens thereon; thus providing a rigid insulating foam
core interposed
or sandwiched between two facer sheets. The resulting product can then be cut
into boards
of desired size and shape. The heat of the exothermic reaction involving
polymerization
and/or crosslinking, is autogenerated in both the laminator and in the
subsequent stacking of
CA 02774509 2012-04-17
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insulation boards to insure complete curing of the core and surface coating of
the facer.
Curing temperatures during stacking can rise up to about 325 F ((163 C) over a
period of up
to 4 days.
As another embodiment involving the above operation, the top and bottom
positioning of the facer sheets can be reversed so that the facer of this
invention is fed and
spaced above a conventional facer in a manner such that its non-coated fibrous
surface faces
the foamable insulating core chemical being contacted on its under surface
with another
facer sheet. The later procedure is practiced where one facer is a rigid
sheet, as in a perlite
or particle board facer as opposed to the flexible facer of this invention
which can be fed to
.. the laminator as a continuous roll. In this case the foamable insulating
core chemical is
surfaced on the rigid facer member and rises to engage the fibrous uncoated
surface of the
present facer.
The insulation boards incorporating the facers of this invention are useful in
commercial roof insulation, residential or commercial wall sheathing etc.
Depending upon
.. the intended use, the present insulation board has a core thickness which
may vary widely,
for example between about 0.5 inch (13 mm) and about 6 inches (152 mm) or
more. The
insulation board will more typically have a core thickness which is within the
range of 1
inch (25 mm) to 4 inches (102 mm).
In the above discussion, it will become apparent that it is also possible to
form the
insulation core separately, i.e. absent contact with the fibers of a facer,
and subsequently
bond one or more of the present facers to the core using suitable adhesives.
In general, the
teachings of United States Patent 4,351,873 are applicable to the formation of
rigid foam
cores and adhesion of facer sheets to at least one surface of such cores.
Polyurethane or polyisocyanurate are most commonly employed as core materials;
.. although other non-elastomeric, foamable chemicals can also be employed.
Examples of the
later include polyvinyl chloride, polystyrene, phenolic resins and the like.
The facers of this invention finds utility in fiberglass mat reinforced gypsum
boards
and the use of such boards in, e.g., exterior insulation systems (El Systems).
Such boards
comprise a set gypsum-containing core having at least one sheet of the facer
of this
.. invention adhered to the set gypsum core by a portion of the set gypsum.
The gypsum
CA 02774509 2012-04-17
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containing core can be sandwiched between two sheets of the facer of this
invention. Such
boards can be manufactured by methods known in the art, such as, for example,
methods
described in United States Patent 4,647,496. The facers of this invention also
find utility on
boards comprised of a cement core. Such boards can be used as a bonding
substrate for,
e.g., the application of tiling. The boards are fastened to walls, floors,
countertops, and the
like, adhesive is applied to the board and the tiles are pressed into the
adhesive.
Gypsum construction board can be made with the facers of this invention by a
process that comprises (1) positioning a wet gypsum composition between a
first facer and a
second facer to make a laminated sheet of wet construction board, wherein the
first facer is
made by the process comprising (i) applying a monomeric composition to a fiber
mat,
wherein the monomeric composition is comprised of a monomer and a filler, (ii)
initiating
polymerization of the monomer within the monomeric composition by exposing the
monomeric composition to ultraviolet light or an electron beam, and (iii)
allowing the
monomer to polymerized to produce the flexible facer, and (2) heating the
laminated sheet
of wet construction board to a temperature which is within the range of 200 F
(93 C) to
700 F (371 C) for a period of time which is sufficient to reduce the moisture
content of the
gypsum to be within the range of 18 to 25 percent. The wet gypsum composition
typically
has a moisture content which is within the range of about 40 percent to about
60 percent.
The laminated sheet of wet construction board is typically heated to a
temperature which is
within the range of 200 F (93 C) to 700 F (371 C). The heating step will
normally be
conducted for a period of about 5 minutes to about 120 minutes. The laminated
sheet of wet
construction board will more typically be heated to a temperature which is
within the range
of about 400 F (204 C) to about 600 F (316 C) for a period of about 30 minutes
to about 60
minutes. In any case, the moisture content of the gypsum will be reduced from
a level of
about 50% to a level which is within the range of about 18% to about 25%. The
moisture
content of the gypsum will typically be reduced to a level of about 21%. The
general
procedure of manufacturing gypsum boards described in United States Patent
6,770,354 can
be implemented in the practice of this invention.
This invention is illustrated by the following examples that are merely for
the
purpose of illustration and are not to be regarded as limiting the scope of
the invention or the
CA 02774509 2012-04-17
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manner in which it can be practiced. Unless specifically indicated otherwise,
parts and
percentages are given by weight.
Example
In order to develop a facer based on an ultraviolet curable binder based
coating, an
aliphatic polyester based urethane diacrylate oligomer blended with 25%
ethoxylated
trimethylated trimethyllol propane triacrylate (CN964E75), a monofunctional
acid ester
(CD9050) used as a adhesion promoting monomer, 2(2-ethoxyethoxy)-ethyl
acrylate mono
functional monomer (SR 256), 1,6 hexanediol diacrylatemonomer low viscosity
monomer
(SR238), photoinitiator Esacure KTO KT046 which is a blend of phosphine oxide,
alpha-
hydroxy ketone and a benzophenone derivative and a inorganic kaoline dry
filler (Kaowhite
from Thiele) was prepared. The proportions of these constituents utilized in
making the
ultraviolet curable binder based coating are shown in Table 1.
As can been seen from Table 1, all the materials used in making the
ultraviolet
curable binder composition were 100% solids. The ultraviolet curable binder
composition
was formulated in the laboratory and applied on a glass mat having a basis
weight of 78
g/m2 using a lab coater. The coated sheets were cured by using a lab unit
consisting of a 400
watt UV lamp at a speed of 20 feet (6 meters) per minute. The coating was
applied to the
glass-mat at a level of about 34 g/ft2 (1200 g/m3) on a dry basis. The total
weight of the
finished sheet was about 40 g/ft2 (1413 g/m3).
Hand sheets were tested for water holdout, cure, caliper, air porosity and
strength
properties. The results are shown in Table 2. This technique of manufacturing
facers offers
the advantage of not emitting any solvents, such as volatile organic compounds
(VOCs) or
water during drying and curing. The process of this invention also offers the
advantage of
utilizing relatively inexpensive fillers, such as kaoline, which reduces the
cost of production
such facers significantly. The process of this invention accordingly offers an
environmentally friendly technique for manufacturing facers that has low
energy
requirements. The facers made by this process exhibit excellent water and
chemical
resistance as well as good exterior durability. Facers can be produced by the
process of this
invention on very compact lines as compared to conventional lines that
requires hot air
CA 02774509 2012-04-17
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circulated in large scale ovens. This process for manufacturing facers by the
technique of
this invention also allows for the incorporation of heat sensitive substrates.
This is not
possible in conventional facer manufacturing techniques due to heat distortion
that occurs by
virtue of the high temperatures that are experienced during the process.
The proposed facer can be used with, but not limited to, foam insulation
boards
composed in part with polyurethane, polyurethane-polyisocyanurate hybrid,
polyphenolic,
expanded polystyrene, extruded polystyrene and/or polyisocyanumte. As can be
seen from
Table 2, the facer made in this experiment offered excellent physical
characteristics.
Table 1
Formulation 1
Formulation 1 % solids % Contribution
CN 964E75 100 50
CD 9050 100 7
SR 256 100 10
SR 238 100 10
ESACURE KTO 46@ Benzophonon I 100 3
Kaowhite _______________________________ 100 20
100
Table 2
Hand sheet results based on formulation 1
Property Value
Basis weight, g/ft2' 40.3
Cure** 0,0
Water holdout*, minutes 60+
Caliper, mils 0.035
Air porosity, 325 Pa (celcels) 33.1
.lensile MD, lb/inch (ASTM 1)828-97) 75.2
Tensile CMD, lb/inch (ASTM D828-97) 42.8
Tear MD, gf 323.5
Tear CMD, gf 487.4
* In the water withhold test, a drop of water (about 0.25 inch (6 mm) to 0.5
inch (13 mm) in
diameter) was placed on the coated side of the facer and the time was measured
for the water
to get through the sample and to bee seen on the other side.
CA 02774509 2012-04-17
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** Cure was measured by cutting the facer made into samples having a size of 1
inch by 6
inches. Two facer samples are pressed together with the coated sides of the
facer samples
facing each other and heated in a press at 225 F (107 C) for 2 minutes at 1
ton (13,790
kiolpascals) of pressure. Then the samples are separated at the end of the
test. The samples
are rated from 0 to 5 on the basis of peel-off characteristics. A rating of 0
is considered to
be the best and 5 is considered to be the worst when the two strips are peeled
apart.
While certain representative embodiments and details have been shown for the
purpose of illustrating the subject invention, it will be apparent to those
skilled in this art
that various changes and modifications can be made therein without departing
from the
.. scope of the subject invention.
