Fire Retardant Compositions and Use Thereof

Europaisches Patentamt J European Patent Office @© Publication number: 0 219 977 Office europeen des brevets A1

EUROPEAN PATENT APPLICATION

@ Date of filing: 18.09.86

® Priority: 18.09.85 US 777159 © Applicant: Eskind, Larry G. 12.08.86 US 895763 1050 Vaquero Road Pebble Beach California 93953(US) @ Date of publication of application: 29.04.87 Bulletin 87/18 © Inventor: Eskind, Larry G. 1050 Vaquero Road ® Designated Contracting States: Pebble Beach California 93953(US) AT BE CH DE FR GB IT LI LU NL SE © Representative: Bannerman, David Gardner et al Withers & Rogers 4 Dyer's Buildings Holborn London, EC1N 2JT(GB)

® Fire retardant compositions and use thereof.

© A fire retardant composition comprising, in percent by weight of the non-volatile solids therein, a non-fibrous aqueous mixture of: (a) 25-90% of an emulsified halogen containing vinyl polymer limited to a maximum bound halogen of 58% on a dry polymer weight basis, selected to bind the composition to a combustible, resilient, foamed or fibrous substrate; (b) 0-4.8% of a metal oxide gas and fume limiting compound; and (c) 1-40% of an afterglow limiting component selected from halogenated naturally occurring oils and fats, having a maximum halogen content of 50%, and organo phosphonates, halogenated organo , phosphonates and substituted organo phosphonates. o» r-

Xerox Copy Centre 0 219 977

FIRE RETARDANT COMPOSITIONS AND USE THEREOF

This invention relates to fire retardant composi- weight percent bound chlorine of 58%, selected to tions and their use on combustible substrates to bind the composition to a combustible, resilient, impart fire retardancy thereto. More particularly, the foamed or fibrous substrate: (b) not more than invention relates to the use of fire retardant com- 4.8% of a metal oxide gas and fume limiting compositions on combustible foamed and fibrous sub- 5 pound: and (c) 1-40% of an afterglow limiting com- strates wherein the resiliency of the substrate is ponent selected from halogenated naturally occur- retained after application of the composition. ring oils, fats, and organo phosphates having a Prior compositions intended for flame or fire maximum halogen content of 50% on the dry proofing foamed or fibrous materials either reduced weight of the formulation. The formulation usually the compressibility and rebound of the materials or w will contain the above essential components and no were water or solvent soluble and therefore only a fibrous component or plasticizers. temporary treatment. The compositions of the The composition, when applied to a suitable present invention are designed to impart fire retar- substrate such as polyurethane foam, limits its dancy to such substrates without affecting the resil- flammability, combustion rate, fuel contribution, iency or normal compressibility and rebound of the 75 melting and smoke or fume production. Similar treated substrate while being inert to water and results are obtained when the composition is ap- other solvents. plied to fibrous materials such as those which may U.S. Patent Nos. 4,018,983; 4,064,359 and be used in a mattress, insulation, upholstery, cloth- 4,225,649 disclose fire retardant compositions ing and general construction materials. which incorporate fibrous materials as a functional 20 Protection is imparted by surface application to part of the compositions, while utilising some com- the substrate, such as by brushing or spraying ponents in common with the present formulations, and/or by a thorough impregnation of the surface they do so in differing amounts. The compositions and the interior of the substrate, such as by soak- of these patents are designed as coatings for elec- ing the substrate in the composition. While soaking trical cables. U.S. Patent No. 4,162,342 discloses a 25 the substrate provides more protection than a sur- process for making foam as an end product, in face treatment (more weight results in more protec- distinction with the present invention which pro- tion), for many applications the surface treatment is vides a composition to be applied to previously adequate. manufactured foamed substrates. U.S. Patent No. Typically, the present compositions are used 3,914,513 discloses the use of chlorinated paraffin 30 as an aqueous mixture with the retardant protection wax as a material used in flame retardant composi- becoming immediately effective upon drying of the tions. U.S. Patent Nos. 3,940,549 and 4,027,062 aqueous diluent. However, further curing of the disclose antimony oxides as being useful in flame product with time enhances the fire protective fea- retardant compositions. tures of the composition. Full curing may take as U.S. Patent No. 4,493,871 discloses the use of 35 long as one week. chlorinated paraffin wax as a material used in flame Upon initial application to a foam substrate the retardant compositions as a plasticizer, in distinc- treated foam may be slightly stiff to the touch tion with the present invention which uses the ma- compared with the untreated foam. This slight stiff- terial to suppress afterglow, any plasticizing effect ness can be removed by rolling or simply flexing being deleterious to the composition. Also men- 40 the foam to soften it without loss of the protective tioned in U.S. Patent No. 4,493,781 are vinylidine properties of the composition. Of most importance, chloride copolymers having higher vinylidine chlo- the foam substrate retains its original resiliency in ride content that used in the present invention. The terms of compressibility and rebound to original use of various metal oxides, in particular antimony configuration upon release of compressive forces. pentoxide, is also mentioned but at a higher level 45 A unique aspect of the present composition than is useful in the present invention. relates to the fact that when a piece of treated foam is subjected to open flame burned the fire retardant coating foams an intumescent char inter- SUMMARY OF THE INVENTION posed between the source of the fire and the so underlying unbumed foam. As a result potentially In accordance with the present invention a fire harmful dripping of burning foam is eliminated. retardant composition is provided comprising in The present composition utilizes a binder for percent by weight of the non-volatile solids therein, the composition to adhere the composition in or on an aqueous mixture of: (a) 25-90% of an emulsified the substrate to be treated. It is noted that the halogen containing vinyl polymer with a maximum binder is a halogen containing vinyl polymer of no 0 219 977 more than 58% bound chlorine on dry weight ba- The present composition includes a metal ox- sis. Although it has been reported that polymers of ide which serves as a gas or fume limiting com- this type are undesirable in that they emit dan- pound. For example, the metal oxide absorbs gerous chemical species upon combustion, the and/or reacts with halogen polymeric binder in the present compositions do not exhibit such hazard- 5 formulation to form non-hazardous products. The ous properties. The metal oxide utilized in the metal oxide may be selected from the following formulation serves to combine with undesirable materials: antimony trioxide, antimony tetroxide, an- gases or fumes emitted by the binder and converts timony pentoxide, aluminum oxide, barium oxide, them to chemical forms that are not as hazarous boron oxide, calcium oxide, silicon dioxide, stannic but instead contribute to the desired fire retardant w oxide, stannous oxide, titanium dioxide and zinc protection. oxide. The metal oxide will typically be present in In general the fire retardant compositions may the composition in the amount of 0-4.8% by weight be formulated as an aqueous mixture containing of the non-volatiie solids in the composition, more about 25-85% by weight of non-volatile solids. In usually about 1-4.5% by weight thereof. Higher the preferred embodiment the percent by weight of 75 levels have been found to embrittle the coating and solids is about 60-70% by weight. There are three the foam substrate causing cracking and dusting essential components in the solids in the stated thus losing protective properties. relative proportions. Each of the three components may be a mixture of materials from its component category. For example, a mixture of metal oxides 20 (3) Afterglow Limiting Component may be used. The composition includes a component designed to suppress or limit afterglow (afterbum, (1) Binder char, ember) in a substrate that has been subjected 25 to fire. The afterglow limiting component is se- An aqueous emulsified halogen containing vinyl lected from halogenated naturally occurring (non- polymer is selected to bind the composition to the petroleum) oils, fats and organo phosphonates that substrate. The vinyl polymer is preferably selected do not tend to plasticize the polymer or binder from vinyl chloride and vinylidine dichloride poly- which would decrease the resiliency of the treated mers and copolymers of no more than 58% bound 30 foam substrate. The maximum halogen, usually chlorine on dry weight basis. Copolymers may be chlorine, content of the afterglow limiting material is formed with ethylene and vinyl chloride 50% as higher levels yield a sticky plasticizing comonomers. An alternative is to form copolymers material. Also, waxes of higher than 50% chlorine with vinyl chloride or vinylidine dichloride with an tend to not bloom to the coating surface thus being acrylic comonomer selected from acrylic and 35 ineffective in eliminating or limiting afterglow. The methacrylic esters. Typical of such esters are following are categories of materials suitable as an methyl acrylate, ethyl acrylate, butyl acrylate, 2- afterglow suppressant: hydroxyl containing ethyl hexyl acrylate, methyl methacrylate, ethyl oligomeric phosphonates, halogenated organo methacrylate butyl methacrylate 2-ethyl hexyl phosphonates, halogenated soybean, cottonseed, methacrylate, or other esters of acrylic acid or 40 peanut or other naturally occurring oils (other than methacrylic acid. The comonomers are combined from petroleum) or fats, and substituted organo so as to achieve the specific properties and to limit phosphonates. Generally, the afterglow limiting the polymeric bound chlorine to a maximum bound component constitutes about 1-40% by weight of chlorine content of 58% by weight of the polymer the non-volatile solids in the composition, usually solids. Higher bound chlorine levels have been 45 about 10-40%, and preferably about 20-40% by found to reduce the resiliency of and stiffen the weight of the composition solids. treated foam substrate. In addition higher bound The present compositions are designed for ap- chlorine levels, i.e. 65% chlorine have been found plication to combustible foamed substrates. Typi- to cause undesirable dusting and cracking of the cally such foam is formed from a polymer selected surface layer of the treated substrate. Typically the so from polyurethane polystyrene-co-butadiene-1 ,3 binder will be present as 25-90% by weight of the and natural rubber. Alternatively, the substrate may non-volatile solids. More usually the binder will be be a combustible fibre such as a non-woven poly- about 40-90%, and preferably about 60-90% by ester fibrous substrate. weight of the solids. The following examples represent formulations 55 of the present fire restardant compositions. The examples indicate the dry weight basis of the ac- (2) Gas and Fume Limiting Component tive components. The remainder of the composition is primarily a soap/surfactant, water diluent system 0 219 977 within which the binder is emulsified. The other suspension water at a suitable alkaline pH. As components may also be introduced into the mix- noted, the solids content is 25-85% by weight. ture in aqueous media. For example, the metal Example 1 is effectively made up to contain about oxide is usually added in a water dispersion or 67% by weight of solids.

EXAMPLE 1

1.) Polyvinylidine dichloride-co-2-ethyl 75.0% of dry weight hexyl acrylate copolymer (58% Cl)

A commercially useful material is UNOCAL Chemical Division, UNOCAL 76RES-P 917, polyvinylidine dichloride/acrylic copolymer. <

2.) Antimony pentoxide 4.5% of dry weight

A commercially useful material is Nyacol Products Inc., Nyacol A1530 and Nyacol A1550, which are aqueous dispersion of antimony pentoxide.

3.) Hydroxyl containing oligomeric 20.5% of dry weight phosphonates

A commercially useful material is Stauffer Chemical Fyrol 51. An alternative commercially available material which may be substituted for or mixed with the Fyrol 51 is Fyrol 6, diethyl-N,N-bis(2-hydroxyethyl) aminomethyl phosphonate.

EXAMPLE 2

1.) Polyvinyl chloride 61.4% of dry weight (50% Cl)

2.) Antimony trioxide 4.8% of dry weight 3.) Fyrol 51 33.8% of dry weight

EXAMPLE 3

1.) Polyethylene vinyl chloride co- 58.100% of dry weight polymer (47% Cl)

2.) Fyrol 51 18.703% of dry weight

3.) Fyrol '6 18.593% of dry weight

4.) Chlorinated soybean oil 4.602% of dry weight (40% Cl)

55 This example illustrates use and performance of the fire retardants, employing the composition of EXAMPLE 4 Example 1 . A sample of polyurethane foam having the dimensions 2"x4"x1" was soaked in the for- 0 219 977

mulation of Example 1 which contained about 67% 4. A fire retardant composition in accordance by weight of solids in water. The sample was with Claim 2, wherein said copolymers are formed removed from the formulation and squeezed on a with an acrylic comonomer selected from acrylic paper towel. The sample was weighed before and and methacrylic esters. after soaking and indicated a 60% weight increase 5 5. A fire retardant composition in accordance following the soaking treatment. The treated sam- with Claim 2, wherein said metal oxide is selected ple was then subjected to a butane torch at 2500 °F from antimony trioxide, antimony tetroxide, anti- for one minute. The sample was glowing orange in mony pentoxide, aluminum oxide, barium oxide, the area of direct flame contact but did not burn boron oxide, calcium oxide, silicon dioxide, stannic and retained its foamed structure. 10 oxide, stannous oxide, titanium dioxide and zinc oxide at a level of no more than 4.8% on dry weight basis. EXAMPLE 5 6. A fire retardant composition in accordance with Claim 5, wherein said metal oxide is antimony Compositions of this invention were subjected 15 pentoxide. to the following tests on a polyurethane foam with- 7. A fire retardant composition in accordance out any cover fabric: (1 ) Restol Chair Test Passed; with Claim 2, wherein said afterglow limiting com- (2) ASTM E162 -Radiant panel, Vertical -5 Watts ponent is a hydroxyl containing oligomeric per centimeter squared for a period of five monutes phosphonate. with (a) Surface Coating of the Foam resulted in a 20 8. A fire retardant composition in accordance 35% weight loss; (b) Saturation of the substrate with Claim 2, wherein said halogen containing vinyl resulted in a weight loss of 26%; (c) ASTM E162 - polymer content is 40-90%, said metal oxide con- Radiant panel, Vertical -3.5 Watts per centimeter tent is 1-4.5% and said afterglow limiting com- squared for a period of two minutes with a Surface pound content is 10-40%. coating resulted in a weight loss of 30%. 25 9. A fire retardant composition in accordance with Claim 1, wherein halogen containing vinyl polymer content is 60-90% and said afterglow limit- Claims ing component content is 20-40%. ' 10. A fire retardant composition in accordance 1. A fire retardant composition comprising in 30 with Claim 1, wherein said halogen containing vinyl percent by weight of the non-volatile solids therein, polymer content is about 60% of a polyvinylidine a non-fibrous aqueous mixture of: dichloride-co-2-ethyl hexyl acrylate polymer; said (a) 25-90% of an emulsified halogen contain- metal oxide content is about 4.8% of antimony ing polymer of no more than 58% bound chlorine pentoxide; and said afterglow limiting component is on dry weight basis selected to bind the composi- 35 about 20.2% of a hydroxyl containing oligomeric tion to a combustible, resilient, foamed or fibrous phosphonate. substrate; 1 1 . A resilient foamed combustible substrate (b) not more than 4.8% of a metal oxide gas containing an effective amount sufficient to impart fume limiting compound; and fire retardancy thereto of a fire retardant composi- (c) 1-40% of an afterglow limiting component 40 tion comprising, in percent by weight of the non- .selected from halogenated naturally occurring oils, volatile solids therein, an aqueous mixture of: fats, halogenated to no more than 50% on dry (a) 25-90% of an emulsified halogen contain- weight basis, and organo phosphonates, haloge- ing vinyl polymer selected to bind the composition nated organo phosponates, and substituted organo to a combustible, resilient, foamed or fibrous sub- phosphonates. 45 strate; 2. A fire retardant composition in accordance (b) 0-4.8% of a metal oxide gas and fume with Claim 1 , wherein said halogen containing vinyl limiting compound; and polymer is selected from vinyl chloride and (c) 1-40% of an afterglow limiting component vinylidine dichloride polymers and copolymers con- selected from halogenated naturally occurring oils taining a maximum of 58% chlorine on dry weight so and fats, containing a maximum of 50% bound basis. chlorine and organo phosphonat.es, halogenated or- 3. A fire retardant composition in accordance gano phosphonates and substituted organo with Claim 2, wherein said copolymers are formed phosphonates. with ethylene and vinyl chloride comonomers con- 12. A method of reducing the flammability of a stituting a polymeric bound chlorine content of no 55 resilient combustible foamed article comprising ap- more than 50% on dry weight basis. plying to said article an effective amount of a fire 0 219 977 10 retardant composition comprising, in percent by 58% bound chlorine on a dry weight basis, is . weight of the non-volatile solids therein, an aque- selected from vinyl chlorine and vinylidine dichlo- ous mixture of: ride polymers and copolymers. (a) 25-90% of an emulsified halogen contain- 18. A method of reducing flammability in ac- ing vinyl polymer, having a maximum of 58% chlo- 5 cordance with Claim 17, wherein said metal oxide rine on a dry weight basis, selected to bind the is selected from antimony trioxide, antimony tetrox- composition to a combustible, resilient, foamed or ide, antimony pentoxide, aluminum oxide, barium fibrous substrate; oxide, boron oxide, calcium oxide, silicon dioxide, (b) not more than 4.8% of a metal oxide gas stannic oxide, stannous oxide, titanium dioxide and and fume limiting compound; and ?o zinc oxide and limited to a maximum of 4.8% on a (c) 1-40% of an afterglow limiting component dry weight basis of the composition. selected from haiogenated naturally occurring oils 19. A method of reducing flammability in ac- and fats, having a maximum halogen content of cordance with Claim 18, wherein said halogen con- 50% chlorine on dry weight basis, and organo taining vinyl polymer limited to a maximum bound phosphonates, haiogenated organo phosphonat.es 75 chlorine content of 58% on dry weight basis con- and substituted organo phosphonates. tent is 40-90% said metal oxide content is 4.5% 13. A method of reducing flammability in ac- and said afterglow limiting component content is cordance with Claim 12, wherein said fire retardant 10-40% with haiogenated afterglow limiting compo- composition is applied to the article by brushing or nents having a maximum bound chlorine content of spraying, whereby substantially only the surface of 20 50%. the article receives said fire retardant composition. 20. A method of reducing flammability in ac- 14. A method of reducing flammability in accordance with Claim 19, wherein said halogen con- cordance with Claim 12, wherein said fire retardant taining vinyl polymer content is about 75% of a composition is applied by soaking the article in polyvinylidine dichloride-co-2-ethyl hexyl acrylate said composition whereby the article receives said 25 copolymer; said metal oxide content is about 4.8% composition on its surface and internally. of antimony pentoxide, and said afterglow limiting 15. A method of reducing flammability in ac- component content is about 20.2% of a hydroxyl cordance with Claim 12, wherein said foamed arti- containing oligomeric phosphonate. cle is formed from a polymer selected from poly- 21. A method for reducing or eliminating melt- urethane, polystyrene-co-butadiene-1 ,3 and natural 30 ing and dripping in accordance with Claims 13 and rubber. 14 when applied to the resilient substrate. 16. A method of reducing flammability in ac- 22. A method for reducing flammability in accordance with Claim 15, wherein said foamed arti- cordance with Claim 21, whereby an intumescent cle is formed from a polyurethane polymer. char is formed that substantially protects that sub- 17. A method of reducing flammability in ac- 35 strate from further damage when in contact with a cordance with Claim 12, wherein said halogen con- flame. taining vinyl polymer, containing a maximum of

55 European Patent Application numoer J) EUROPEAN SEARCH REPORT Office

EP 86 30 7202

DOCUMENTS CONSIDERED TO BE RELEVANT Citation of document with indication, where appropriate, Relevant CLASSIFICATION OF THE Category of relevant passages to claim APPLICATION (Int. CM)

EP-A-0 037 636 (ELSON AND 1,2,5. C 09 K 21/14 ROBBINS) 11,12, C 09 D 5/18 15,16, 18 * Page 1, lines 12-17; page 2, lines 6-12,16-23; page 3, lines 7-26; examples; claims 1,2,5 *

FR-A-2 367 809 (NL INDUSTRIES) 1,2,5 * Page 1, lines 22-40; page 2, lines 21-39; page 3, lines 2-16; page 10, lines 1-14; examples 12,13 *

FR-A-2 430 966 (SICOF) 1,2,5, 11,12. 15, 16. 18 TECHNICAL FIELDS SEARCHED (Int CM i * Page 1, lines 1-2,15-18,32-36; page 2, lines 9-24,38-39; page 3, lines 1-5 * C 09 K C 09 D

FR-A-2 351 163 (NL INDUSTRIES) 1,2,5 * Page 2, lines 32-40; page 3, lines 1-19,37-40 *

@/-

The present search report has been drawn up for all claims Place of search Oate of completion of the search Examiner THE HAGUE 17-12-1986 BOULON A . F . J , CATEGORY CF CITED DOCUMENTS T theory or principle underlying the invention E eartier patent document, but published on, or X particularly relevant if taken alone after the filing date Y particularly relevant if combined with another D : document cited in the application document of the same category L document cited for other reasons A technological background O non-written disclosure & : member of the same patent family, corresponding P intermediate document document J) European Patent Application number EUROPEAN SEARCH REPORT Office

EP 86 30 7202

DOCUMENTS CONSIDERED TO BE RELEVANT Page 2 Citation of document with indication, where appropriate, Relevant CLASSIFICATION OF THE Category of relevant passages to claim APPLICATION (Int. Cl.»)

JOURNAL OF FIRE RETARD ANT 1,7 CHEMISTRY, vol. 9, no. 1, February 1982, pages 39-49, Technomic Publishing Co., Inc., Westport, Connecticut, US; E.D.WEIL et al . : "Oligomeric phosphorus esters with flame retardant utility" * The whole document *

TECHNICAL FIELDS SEARCHED (Int Cl *j

The present search report has be«n drawn up for all claims Place of search Date of completion of the search Examiner THE HAGUE 17-12-1986 BOULON A.F.J.

CATEGORY CF CITED DOCUMENTS T theory or principle underlying the invention E : earlier patent document, but published on. or X particularly relevant if taken alone after the filing date Y : particularly relevant if combined with another D : document cited in the application document of the same category L document cited for other reasons A technological background O non-written disclosure & : member of the same patent family, corresponding P intermediate document document