This invention relates to a laminar cushioning material that is resistant
to and does not participate in fire. More particularly, this invention relates
to a laminar cushioning material comprising an outer layer of foamed polyphosphazene
and an inner layer of foamed polyurethane.
Pressure for increased flammability resistance of bedding and furniture
materials has been on the rise over the last few years. Federal standards originally
implemented for cigarette smolder resistance to mattresses has given way to more
comprehensive requirements for furniture, aircraft seats and the like including
open flame and vertical flame tests.
The typical structure of cushioning material comprises a core of
fire resistant polyurethane having an upholstery outer cover. Smolder resistance
is commonly acceptable. In full-scale real life fires, the outer fabric cover
rapidly breaks down and the polyurethane core becomes involved in the fire, producing
large volumes of potentially lethal smoke, combustible gases and toxic fumes.
In order to pass FAA regulations, seat manufacturers have chosen to use a foam
core seat cushion fully encased by a fire-blocking sheet which delays the onset
of ignition and retards involvement of the core in the fire. However, such fire
blocking sheet is not a requirement of any present Federal or state regulations
for furniture or bedding materials.
Mueller in U.S. Pat. No. 4,818,603 discloses a heavy metal loaded
polyphosphazene septum bonded to the surface of a foamed polyimide.
Thompson U.S. Pat. No. 3,994,838 describes polyaryloxy phosphazene
foams and suggest their use as thermal insulation because of their fire resistance.
Polyorganophosphazenes are known compositions. Polyaryloxyphosphazenes
are described in U.S. Pat. No. 3,856,713. Polyfluoroalkoxyphosphazenes are described
in U.S. Pat. No. 3,970,533. Methods of curing such polymers by sulfur vulcanization,
free-radical (e.g., peroxide) cure and by reaction are also well known.
The present invention is directed to a fire resistant cushioning
material that comprises a fire-blocking sheet and a polyurethane core. Such cushioning
material will pass California Technical Bulletin 133 test, as developed by the
California Department of Consumer Affairs, Bureau of Home Furnishings. The cushioning
material is a laminar structure comprising an outer foamed polyphosphazene lamella
and a foamed polyurethane inner lamella. The foamed polyphosphazene lamella may
contain a substantially unfoamed thin layer at the top and/or bottom surface. The
polyphosphazene lamella will cover and/or be attached to the polyurethane lamella
by, for example, an adhesive, physical fasteners, and the like and lie on top of
or it may partially or totally wrap around the polyurethane lamella. The composite
cushioning material may optionally be covered by a decorative fabric such as is
commonly used for seat cushions, upholstered furniture, mattresses and the like.
In some cases it may be preferred to laminate the polyphosphazene lamella to the
decorative fabric and subsequently cover the polyurethane lamella with this laminate.
A preferred embodiment of the present invention is a composite material
having utility as a fire resistant cushioning material which comprises a polyphosphazene
lamella overlaying or wrapping around a polyurethane lamella.
Polyorganophosphazenes have a linear backbone of
units in which R&sub1; and R&sub2; are the same or different organic
groups and n has a value from about 10 up to 100,000 or more. They are made by
first heating purified phosphonitrilic chloride trimer to about 200°-250°C in an
inert atmosphere preferably in the presence of one of the known catalyst for the
polymerization. After about 12-24 hours, a linear polyphosphonitrilic chloride
("chloropolymer") will form having an intrinsic viscosity of about 0.9-1.1 deciliters/gram.
This can be purified by dissolving in a solvent such as tetrahydrofuran and then
mixing the solution with an aliphatic hydrocarbon such as heptane causing the
high molecular weight chloropolymer to precipitate. The purified chloropolymer
can then be dissolved in a solvent such as tetrahydrofuran (THF) and a THF solution
of the desired sodium alkoxide or aryloxide added to it. These compounds react
to form a polyorganophosphazene in which the organo groups correspond to the alkoxide
or aryloxide groups in the THF solution. The product can be washed and precipitated
with water. The precipitated gum is then dried and then compounded following standard
rubber technology such as by intensive mixing in a Banbury mixer.
The substituents bonded to phosphorus can vary widely and include
substituted and unsubstituted alkoxy and aryloxy groups wherein the substituent
groups on the alkoxy or aryloxy can be halogen (e.g., chlorine, fluorine), alkyl,
alkoxy, polyalkoxy, dialkylamino, trifluoromethyl, aryloxy, alkenyl (e.g., allyl).
U.S. Pat. No. 3,994,838 describes a phosphazene useful in making
the fire blocking sheet used in this invention.
The preferred polyorganophosphazene is a polyaryloxy phosphazene
such as that described in Rose et al. U.S. Pat. No. 3,856,713. These polymers have
both phenoxy and alkylphenoxy groups substituted on phosphorus. In a more preferred
embodiment about 20-79 mole percent of the substituent groups on phosphorus are
phenoxy and about 79-20 mole percent are lower alkyl phenoxy, especially p-ethylphenoxy.
At least one mole percent and up to about 15 mole percent of the substituent groups
on phosphorus are olefinically unsaturated groups such as allyl, o-allylphenoxy,
p-allylphenoxy, eugenoxy, isoeugenoxy and the like. Most preferably the olefinically
unsaturated groups are o-allylphenoxy. These groups promote crosslinking during
the cure stage whether by sulfur-curing or peroxide-curing. In order to produce
the foam used in the present invention, from about 1 to about 40 parts per hundred
based on phosphazene polymer of at least one chemical blowing agent and activator
are required. Azodicarbonamide is typical of such blowing agent. Foams with densities
as low as at least 3.4 lbs/ft³ or lower are effective in the barrier sheets
of the present invention.
The polyorganophosphazene gum is compounded with certain additives
to enhance its properties. The additives include fillers such as aluminum trihydrate
(ATH), magnesium hydroxide, hydrated magnesium carbonate, silane treated silica
and the like; processing aids such as silicone rubber, e.g., Silastic HA-2 (Dow
Corning Company); and stabilizers such as Ethanox 330 or 376 Antioxidant, (Ethyl
The polyorganophosphazene sheet can be cured or uncured in the composite
material. Preferably the sheet is cured. When used as a fire resistant cushioning
material, curing is necessary to give adequate physical integrity.
Curing agents such as a peroxide (e.g., t-butyl perbenzoate) or the
combination of sulfur and a vulcanizing accelerator system, e.g., Methyl Zimate,
Butyl Zimate, Vanax 552 (products of R.T. Vanderbilt Company) can be used.
A typical formulation used in making the phosphazene lamella is as
The ingredients are mixed in a conventional Banbury mixer, sheeted
out on a 2-roll mill to the desired thickness and then fed to a calender to form
the uncured polymer which is then cured in an autoclave at about 150°C for 360
Because of the mixing and subsequent curing process, a polyphosphazene
foam results that typically is composed of a thin layer of substantially unfoamed
material on both sides of the foamed polymer layer. A product with a single layer
of substantially unfoamed material is readily obtained from this structure by
cutting the sheet in two. A polyphosphazene without any substantially unfoamed
layers is obtained by cutting and removing the unfoamed "skins" from both sides
of the foamed sheet.
Where one or both of the unfoamed portions are desired then the thickness
of these unfoamed lamelliform layers can be adjusted depending on mixing and curing
conditions. Since the fire blocking ability of the polyphosphazene is dependent
on the thickness of both the unfoamed layer as well as the foamed layer, it is
important to control mixing and curing to result in optimal properties. Thus,
the lamelliform, substantially unfoamed layer should have a minimum thickness of
about 0.01 mm but should not exceed about 0.2 mm. This unfoamed layer can play
a significant role in the fire barrier property of the cushioning material and
also provides good physical integrity to the outer surface of foamed polyphosphazene
lamella. Resistance to puncture for example is improved by the presence of such
The substantially foamed second layer, in order to be an effective
fire barrier should be at least 0.5 mm in thickness. Because of economic considerations
the foam should be as thin as possible, typically 1.4 mm in thickness.
Effective fire protection at decreased sheet thicknesses can be provided
by novel polyphosphazene compositions which differ from those described above in
that a monomeric flame retardant is incorporated therein, usually in an amount
such as to constitute less than about 40 wt.% of the formulation.
Although a number of different types of flame retardants may be incorporated
into the filled polymeric compositions of this invention, monomeric halogen-containing
flame retardants are especially effective, and chlorinated, but especially brominated
flame retardants are preferred. A number of such flame retardants are known, and
the class includes, e.g., tetrabromophthalic anhydride, esters of tetrabromophthalic
acid, dibromoneopentylglycol, tetrabromo-bisphenol A, hexabromocyclododecane,
dibromoethyl-dibromocyclohexane, octabromodiphenyl oxide, decabromo-diphenyl oxide,
tetradecabromodiphenoxybenzene, ethylene bis-tetrabromophthalimide, ethylene bis-dibromonorbornane
dicarboximide, pentabromodiphenyl oxide, and vinyl bromide. Among these listed
materials, ethylene bis-tetrabromophthalimide (EBTBP) and decabromodiphenyl oxide
(DBDPO) are especially useful. The preparation of ethylene bis-tetrabromophthalimide
is described, for example, in U.S. 4,914,212. The preparation of decabromodiphenyl
oxide is described in U.S. 4,287,373. Both of these flame retardants are available
in commerce from Ethyl Corporation as Saytex® BT-93 and Saytex® 102, respectively.
In addition to the monomeric halogen-containing organic flame retardant,
it is often desirable, although not required, that an oxide of a Group V element
also be present, e.g., a bizmuth, arsenic, phosphorus or antimony oxide. These
oxides, when combined with a halogen-containing, especially bromine-containing,
flame retardant, decrease the amount of the latter which is required to achieve
a given level of flame retardancy. The relative amounts of the various components
in the filled polymeric compositions of this invention are as set forth in the
following generalized formulation:
The monomeric flame retardant in the composition includes both the
halogen-containing organic flame retardant and the Group V metal oxide optionally
present. The formulation contains at least about 5 parts by weight of a halogen,
preferably bromine-containing organic fire retardant.
If the formulation is not to be foamed, the blowing agent and activator
Polyurethanes are a well recognized class of polymer taking their
name from ethyl carbamate (urethane). They typically have the repeating unit [R-NH-C(O)O-R&min;-O(O)CNH]
where R is usually an aromatic polyisocyanate and R&min; an aromatic or aliphatic
Representative polyols which may be employed in the preparation of
the flame retardant polyurethane foams are well known to those skilled in the art.
They are often prepared by the catalytic condensation of an alkylene oxide or
mixture of alkylene oxides either simultaneously or sequentially with an organic
compound having at least two active hydrogen atoms, such as disclosed in U.S.
Pat. Nos. 1,922,459; 3,190,927; and 3,346,557. Representative polyols include polyhydroxyl-containing
polyesters, polyoxyalkylene polyether polyols, polyhydroxy-terminated polyurethane
polymers, polyhydroxyl-containing phosphorus compounds, and alkylene oxide adducts
of polyhydric polythioesters, polyacetals, aliphatic polyols and thiols, ammonia,
and amines including aromatic, aliphatic, and heterocyclic amines, as well as
mixtures thereof. Alkylene oxide adducts of compounds which contain 2 or more different
groups within the above-defined classes may also be used, for example, amino alcohols
which contain an amino group and a hydroxyl group. Also, alkylene oxide adducts
of compounds which contain one SH group and one OH group as well as those which
contain an amino group and an SH group may be used. Generally, the equivalent weight
of the polyol will vary from 100 to 10,000.
The polyhydroxy polyesters are typically prepared from the reaction
of polycarboxylic acids and polyhydric alcohols. Any suitable polycarboxylic acid
may be used including oxalic acid, malonic acid, maleic acid, fumaric acid, isophthalic
acid, terephthalic acid, 1,4-cyclo-hexanedicarboxylic acid and the like. Any suitable
polyhydric alcohol, including both aliphatic and aromatic, may be used such as
ethylene glycol, propylene glycol, sorbitol, etc. Also included within the term
"polyhydric alcohol" are compounds derived from phenol such as 2,2-bis(4-hydroxyphenyl)propane,
commonly known as Bisphenol A.
The hydroxyl-containing polyester may also be a polyester amide such
as is obtained by including some amine or amino alcohol in the reactants for the
preparation of the polyesters. Thus, polyester amides may be obtained by condensing
an amino alcohol such as ethanolamine with the polycarboxylic acids set forth
above or they may be made using the same components that make up the hydroxyl-containing
polyester with only a portion of the components being a diamine such as ethylene
Any suitable polyoxyalkylene polyether polyol may be used such as
the polymerization product of an alkylene oxide or a mixture of alkylene oxides
with a polyhydric alcohol. Any suitable polyhydric alcohol may be used such as
those disclosed above for use in the preparation of the hydroxy-terminated polyesters.
Any suitable alkylene oxide may be used such as ethylene oxide, propylene oxide,
butylene oxide, amylene oxide, and mixtures of these oxides. The polyoxyalkylene
polyether polyols may be prepared from other starting materials such as tetrahydrofuran
and alkylene oxide-tetrahydrofuran mixtures; epihalohydrins such as epichlorohydrin;
as well as aralkylene oxides such as styrene oxide. The polyoxyalkylene polyether
polyols may have either primary or secondary hydroxyl groups. Included among the
polyether polyols are polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene
glycol, polytetramethylene glycol, block copolymers, for example, combinations
of polyoxypropylene and polyoxyethylene glycols, poly-1,2-oxybutylene and polyoxyethylene
glycols, and random copolymer glycols prepared from blends of two or more alkylene
oxides or by the sequential addition of two or more alkylene oxides. The polyoxyalkylene
polyether polyols may be prepared by any known process such as, for example, the
process disclosed by Wurtz in 1859 and Encylopedia of Chemical Technology, Vol.
7, pp. 257-262, published by Interscience Publishers, Inc. (1951) or in U.S. Pat.
No. 1,922,459. Polyethers which are preferred include the alkylene oxide addition
products of trimethylolpropane, glycerine, pentaerythritol, sucrose, sorbitol,
propylene glycol, and 2,2&min;-(4,4&min;-hydroxyphenyl)propane and blends thereof
having equivalent weights of from 100 to 10,000.
Suitable polyhydric polythioethers which may be condensed with alkylene
oxides include the condensation product of thiodiglycol or the reaction product
of a dicarboxylic acid such as is disclosed above for the preparation of the hydroxyl-containing
polyesters with any other suitable thioether glycol.
Polyhydroxyl-containing phosphorus compounds which may be used include
those compounds disclosed in U.S. Pat. No. 3,639,542. Preferred polyhydroxyl-containing
phosphorus compounds are prepared from alkylene oxides and acids of phosphorus
having a P&sub2;O&sub5; equivalency of from 72 percent to about 95 percent.
The polyurethane foams employed in the present invention are generally
prepared by the reaction of one or more of the illustrated polyols with an organic
polyisocyanate in the presence of a blowing agent and optionally in the presence
of additional polyhydroxyl-containing components, chain-extending agents, catalysts,
surface-active agents, stabilizers, dyes, fillers and pigments. Suitable processes
for the preparation of cellular polyurethane foams are disclosed in U.S. Reissue
Pat. 24,514 together with suitable machinery to be used in conjunction therewith.
When water is added as the blowing agent, corresponding quantities of excess isocyanate
to react with the water and produce carbon dioxide may be used.
It is possible to proceed with the preparation of the polyurethane
foams by a prepolymer technique wherein an excess of organic polyisocyanate is
reacted in a first step with the polyol of the present invention to prepare a
prepolymer having free isocyanate groups which is then reacted in a second step
with water and/or additional polyol to prepare a foam. Alternatively, the components
may be reacted in a single working step commonly known as the "one-shot" technique
of preparing polyurethanes. Furthermore, instead of water, low boiling hydrocarbons
such as pentane, hexane, heptane, pentene, and heptene; azo compounds such as
azohexahydrobenzodinitrile; halogenated hydrocarbons such as dichlorodifluoromethane,
trichlorofluoromethane, dichlorodifluoroethane, vinylidene chloride, and methylene
chloride may be used as blowing agents.
Organic polyisocyanates which may be employed include aromatic, aliphatic,
and cycloaliphatic polyisocyanates and combinations thereof. Representatives of
these types are the diisocyanates such as m-phenylene diisocyanate, 2,4-toluene
diisocyanate, 2,6-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diioscyanate,
hexamethylene diisocyanate, tetramethylene diisocyanate, cyclohexane, 1,4-diisocyanate,
hexahydrotoluene diisocyanate (and isomers), naphthalene-1,5-diisocyanate, 1-methoxy-phenyl-2,4-diisocyanate,
4,4&min;-diphenylmethane diisocyanate, 4,4&min;-biphenylene diisocyanate, 3,3&min;-dimethoxy-4,4&min;-biphenyl
diisocyanate, 3,3&min;-methyl-4,4&min;-biphenyl diisocyanate and 3,3&min;-dimethyl-diphenylmethane-4,4&min;-diisocyanate;
the triisocyanates such as 4,4&min;,4&sec;-triphenylmethane triisocyanate, and
toluene 2,4,6-triisocyanate, and the tetraisocyanates such as 4,4&min;-dimethyldiphenylmethane-2,2&min;-5,5&min;-tetraisocyanate
and polymeric polyisocyanates such as polymethylene polyphenylene polyisocyanate.
Especially useful due to their availability and properties are toluene diisocyanate,
4,4&min;-diphenylmethane diisocyanate and polymethylene polyphenylene polyisocyanate.
Toluene diisocyanate is preferred.
Crude polyisocyanates may also be used in the compositions of the
present invention, such as crude toluene diisocyanate obtained by the phosgenation
of a mixture of toluene diamines or crude diphenylmethane isocyanate obtained
by the phosgenation of crude diphenylmethane diamine. The preferred or crude isocyanates
are disclosed in U.S. Pat. No. 3,215,652.
Chain-extending agents which may be employed in the preparation of
the polyurethane foams include those compounds having at least two functional groups
bearing active hydrogen atoms such as water, hydrazine, primary and secondary
diamines, amino alcohols, amino acids, hydroxy acids, glycols, or mixtures thereof.
A preferred group of chain-extending agents includes water, ethylene glycol, 1,4-butanediol
and primary and secondary diamines which react more readily with the prepolymer
than does water such as phenylene diamine, 1,4-cyclohexane-bis-(methylamine),
ethylenediamine, diethylenetriamine, N-(2-hydroxypropyl)-ethylenediamine, N-(2-hydroxy-propyl)ethylenediamine,
N,N&min;-di(2-hydroxypropyl)-ethylene-diamine, piperazine, and 2-methylpiperazine.
Any suitable catalyst may be used including tertiary amines such
as, for example, triethylenediamine, N-methylmorpholine, N-ethylmorpholine, diethylethanol-amine,
N-cocomorpholine, 1-methyl-4-diamethylaminoethyl-piperazine, 3-methoxypropyldimethylamine,
N,N,N&min;-trimethylisopropyl propylenediamine, 3-diethylaminopropyl-diethylamine,
dimethylbenzylamine, and the like. Other suitable catalysts are, for example,
stannous chloride, dibutyltin di-2-ethyl hexanoate, stannous oxide, as well as
other organometallic compounds such as are disclosed in U.S. Pat. No. 2,846,408.
A surface-active agent is generally necessary for production of high
grade polyurethane foam according to the present invention, since in the absence
of same, the foams collapse or contain very large uneven cells. Numerous surface-active
agents have been found satisfactory. Nonionic surface active agents are preferred.
Of these the nonionic surface active agents such as the tertiary amine or alkanolamine
salts of long chain alkyl acid sulfate esters, alkyl sulfonic esters, and alkyl
arylsulfonic acids are not preferred.
Flame retarded polyurethane foams also have dispersed throughout
their mass melamine particles that may vary in particle size from about 1.5 microns
to less than 10 microns. The smaller particle sizes are preferred. Typically such
melamine particles are present in the foam from concentrations of about 5% by weight
to about 55% by weight based on the total amount of polyurethane starting materials.
Other flame retardant additives may also be included in the polyurethane
foam. Among such other flame retardants, and particularly useful with melamine
are tetrakis(2-chloroethyl)- ethylene phosphonate, pentabromodiphenyl oxide, tris(1,3-dichloropropyl)-phosphate,
tris(beta-chlorethyl)phosphate, molybdenum trioxide, ammonium molybdate, ammonium
phosphate, pentabromodiphenyloxide, tricresyl phosphate, 2,3-dibromopropanol,
hexabromocyclododecane, dibromoethyl-dibromocyclohexane, tris(2,3-dibromopropyl)phosphate,
and tris(beta-chloropropyl)phosphate. They are preferably used in an amount of
from about 1 to about 15 weight percent of the total weight of the composition.
The actual construction of the cushioning material is shown in its
simpliest form in Figure 1. In this cross sectional view of a cushion structure
(10), the foamed polyphosphazene outer lamella (11) (approximately 0.25 to 5 mm
in thickness; preferably about 1 to 3 mm thick) composed of the substantially unfoamed
layer (12) and the foamed layer (13) covers the surface of the foamed polyurethane
lower lamella (14). This lower lamella may be from 10 to 300 mm in thickness or
more, but is usually 50 to 150 mm in thickness. As noted earlier, these lamella
may be secured by physical fasteners (staples, nails, screws, etc.) or by adhesives.
Such adhesives are disclosed for example in U.S. Pat. No. 4,468,431. Other useful
Figure 2 shows an embodiment of the present invention where the foamed
polyphosphazene wraps around the polyurethane lamella. The cushioning material
(20) has an outer, upper polyphosphazene sheet of substantially unfoamed polyphosphazene
(21) and substantially foamed polyphosphazene (22) and an outer, lower polyphosphazene
sheet of substantially unfoamed polyphosphazene (28) and substantially foamed
polyphosphazene (29). Side wraps of the polyphosphazene sheet extend down either
side of the polyurethane lamella (27). Thus, on either side of the polyurethane
substantially unfoamed layers (23 and 25), overlaying substantially foamed layers
(24 and 26) can be seen to fully envelope the foamed polyurethane (27). It should
be noted that depending on the use, the entire foamed polyurethane lamella can
be enveloped by the fire barrier sheet as shown in Figure 2 or only various parts
Testing For Flammability of Cushioning Material
Testing for Examples 1-18 was conducted by burning five double sheets
of newspaper on a full scale mock-up protected by a 4 sided enclosure. Weight loss
was the criterion for passage or failure of the sample in accordance with the
weight loss requirements given in California Technical Bulletin-133.
The polyphosphazene foams used in these tests (Examples 1-18) had
the following formulations:
1 - The fabric coverings from the above examples are as follows:
Polyester - 44% polyester, 52% rayon, 4% polypropylene fabric of jacquard weave
and fabric weight of 15 oz/yd². Pattern and color are wedgewood. By Culp, Inc.;
Nylon - 100% nylon fabric. Pattern is winner and color is charcoal. It has
a fabric weight of 15 oz/yd². By Culp, Inc.;
Polypropylene - 100% polypropylene fabric. Pattern is tribute and color is
ash. It has a fabric weight of 15 oz/yd². By Culp, Inc.;
Wool - 100% wool fabric. Pattern is Sheffield and color is green. It has a
fabric weight of 20 oz/yd². By Shelby Williams; and
Cotton - 100% cotton velvet. The color is blueberry. It has a fabric weight
of 21 oz/yd². By J.L. DeBall & Grimes of America.
2 - Cal-117 is a polyurethane flexible foam capable of passing the requirements
of a California Technical Bulletin 117. The foam used in these tests had a density
of 1.8 lb/ft³.
3 - Results mean the following:
Pass - where the test specimen has less than or equal to 10% weight loss in
the first ten minutes of testing (as required by Cal 133).
Fail - where the test specimen has a weight loss of greater than 10% in the
first ten minutes of testing (as required by Cal 133).
Borderline Fail - where the test specimen has a weight loss of close to 10%
in the first ten minutes of testing.
4 - The cushion dimension for the Foam I and Foam II were back and bottom cushions
16&sec; × 16&sec; × 3&sec;.
5 - The skin thickness is approximately.01-.05 mm.
Example 21Filled Polymeric Compositions
The aforesaid filled polymeric compositions are sheeted, and some
are foamed as described above, to a size of approximately 36&sec; × 25&sec;
in various thicknesses. The subsequently cured sheets are adhesively bonded or
laminated to polyurethane foam cushion samples, which have a density of about 1.8
lb./ft.³ and meet the requirements of California Technical Bulletin 117, and
then covered with various upholstery fabrics. The constructions are then tested
for fire-resistance by burning five double sheets of newspaper on a full scale
mock-up protected by a four-sided enclosure. Weight loss is the criterion for passage
or failure in accordance with the weight loss requirement (i.e., 10% weight loss/10
minutes) given in California Technical Bulletin 133. The results of these tests
are set forth in Example 22.
Example 22Fire Test Results
Cotton - 100% cotton velvet. The color is blueberry. It
A composite fire resistant laminar cushioning material (10, 20) comprising
(i) a foamed polyphosphazene outer lamella (11) having a lamelliform, substantially
unfoamed first outer layer (12, 21, 23, 25, 28) and a substantially foamed second
layer (13, 22, 24, 26, 29) and (ii) a foamed polyurethane inner lamella (14, 27).
A cushioning material according to Claim 1 wherein said foamed polyphosphazene
is a polyaryloxy-phosphazene.
A cushioning material according to Claim 1 or 2 wherein the aryloxy groups
of said polyaryloxyphosphazene comprise phenoxy and C&sub1; to C&sub6; linear or
branched alkyl-substituted phenoxy groups.
A cushioning material according to any one of the preceding claims wherein
the foamed polyphosphazene outer lamella (11) further comprises a lamelliform
substantially unfoamed third inner layer.
A cushioning material according to any one of the preceding claims in which
the polyphosphazene lamella includes at least one monomeric flame retardant material.
A polymeric composition adapted to protect cushioning against fire, said composition
comprising at least one polyorganophosphazene of the formula
wherein R&sub1; and R&sub2; are the same or different organic groups and n is an
integer of from 10 to 10&sup5;, in combination with at least one monomeric flame
A composition according to claim 6 in which the polyorganophosphazene is a
A composition according to claim 6 or 7 wherein the aryloxy groups of said
polyaryloxyphosphazene comprise phenoxy groups and phenoxy groups substituted with
lower alkyl groups.
A composition according to any one of claims 6 to 8 wherein the flame retardant
includes a halogenated flame retardant.
A composition of claim 9 wherein said halogenated flame retardant is ethylene-bis-tetrabromophthalimide
or decabromodiphenyl oxide.