WO1998000461A1

WO1998000461A1 - Intumescent fire-retardant additive for resin and coal tar coating materials

Info

Publication number: WO1998000461A1
Application number: PCT/US1997/011246
Authority: WO
Inventors: Samuel Gottfried
Original assignee: No Fire Technologies, Inc.
Priority date: 1996-07-03
Filing date: 1997-06-28
Publication date: 1998-01-08
Also published as: IT1296115B1; ITRM970395A0; ITRM970395A1; AU3582897A

Abstract

A fire-retardant material in powder form used as an additive for many types of plastics, epoxies, urethanes, resins and coal tars including an intumescent base material having a foaming agent, a blowing agent, and a charring agent; a flame spread reduction agent which provides protection against radiant heat flux density of up to 600 kW per square meter for a duration of 5 minutes; and refractory fibers in the additive material.

Description

INTUMESCENT FIRE-RETARDANT ADDITIVE FOR RESIN AND COAL TAR COATING MATERIALS

FIELD OF THE INVENTION

The present invention relates to an intumescent fire- retardant additive used in conjunction with flammable coating materials such as urethanes, epoxies, coal tars, PVC, and other types of resins to substantially decrease their fla mability for use in numerous applications, such as undercoatings and top coating materials. More particularly, the fire-retardant additive includes intumescent base materials, flame spread reduction agents, and refractory fibers.

BACKGROUND OF THE INVENTION

Intumescent additive materials have been known for many years and have been used as flame inhibitors for various substrates which provide some degree of thermal protection.

Substrates, such as wood composites, and various types of plastics, such as PVC, thermoplastics, and epoxies, have incorporated the additives to make them more fire and heat retardant.

However, in many applications for PVC, thermoplastics, coal tars and epoxies, the additive is impractical for reasons other than fire protection, such as: reduced abrasion resistance, water resistance, and other environmental factors. Additionally, the fire protection performance degrades substantially when exposed to heat for a prolonged period. For example, with the increased use of wood composite products for use in home construction applications, or with the increased use of epoxy resins as an exterior coating in paints for home construction, current fire-retardant additive materials used in conjunction with flammable coating materials do not provide adequate or sufficient protection from fire and heat for more than a few minutes. Currently, there is no single fire-retardant additive material when incorporated with flammable coating materials, such as PVC's, epoxy resins, coal tars, and urethanes, which have all of the following desirable features :

1. An additive that is a dry powder form;

2. Provides significant reduction in surface flame spread characteristics;

3. Provides protection against radiant heat flux density of up to 600 kwatt/M² for a duration of 300 seconds;

4. Provides a low rate of thermal transmission within the various coating materials; and 5. Reduces the flame spread of various coating materials being used on various substrates.

Also, in many other applications fire-retardant additives are used in various coating materials which then are applied to various substrates such as wood, PVC, thermoplastics, metals, fiberglass, and epoxies. These coating materials are impractical for reasons other than fire protection, as they lack resistance to abrasion, impact, water, corrosion, and other environmental factors. Because of these factors, present coating materials using a fire- retardant additive substantially degrade in use and do not provide protection from fire and heat for a sufficient time duration during a fire. There is a need for a new and improved fire-retardant additive used in various coating materials that would not degrade in use and would provide substantial protection from fire and heat for a long duration if a fire were to occur by reducing the flammability of the coating materials. The coating materials used should have application for use on a variety of substrates such as iron, steel, stainless steel, aluminum, titanium, copper, brass, and other metals, wood, plywood, particle board, and other wood products, plastics, PVC, thermoplastics, fiberglass, epoxies, paints, resins and the like for many applications in building construction, transportation, utilities, telecommunications, marine construction, industrial manufacturing, and the like.

DESCRIPTION OF THE PRIOR ART Intumescent fire-retardant additive materials of various compositions being used in various coating materials on a variety of materials of construction have been disclosed in the prior art. For example, U.S. Patent Nos . 3,969,291; 4,748,066; 5,085,897; 5,108,832; 5,331,030; and 5,414,031 all disclose intumescent fire-retardant additives for coating materials, but none of the prior art patents disclose a chemical composition similar to the present invention.

Accordingly, it is an object of the present invention to provide a fire-retardant additive product for mixing with a flammable coating material, such as PVC, coal tar, epoxy resin or urethane, to provide an effective fire-retardant coating for a substrate that when used as an additive is able to withstand a continuously maintained temperature as high as 2,000°F, without significantly degrading the environmental and mechanical properties of the substrate being coated.

Another object of the present invention is to provide an intumescent fire-retardant additive composition that includes a novel combination of an intumescent base material having a foaming agent, a charring agent, and a blowing agent; a flame spread reduction agent; and refractory fibers. The additive may have optional filler and pigment components. Another object of the present invention is to provide an intumescent fire-retardant additive composition that is in a dry powder form for ease of handling, mixing and incorporating into a coating material at the point of manufacture. Another object of the present invention is to provide an intumescent fire-retardant additive composition that combines with a flammable coating material, such as PVC, coal tar, epoxy resin, or urethane, to provide a significant reduction in surface flame spread characteristics, protection against radiant heat flux density of up to 600 kw/M² for a duration of 5 minutes, a low rate of thermal transmission and reduced flammability to the coating material being used.

Another object of the present invention is to provide an intumescent fire-retardant additive composition that when combined with a PVC coating material has application in the transportation industry for vehicle under coating, exhaust systems, gas tanks, engine compartment, fire walls, catalytic converters, hoods and floors.

Another object of the present invention is to provide an intumescent fire-retardant additive composition that when combined with an epoxy resin or urethane coating material has application in residential, hotel, commercial office and industrial plant construction where the additive coating material is used as an exterior coating which also helps to weatherproof the structure being constructed.

Another object of the present invention is to provide an intumescent fire-retardant additive composition that when combined with a coal tar coating material has application in the marine, telecommunications, utilities, and petroleum industries where the additive coating material is used for bulkheads, cables, conduits, offshore oil drilling platforms, seals, pipeline wraps and chemical storage tanks for the prevention of water, salt-water and chemical corrosion to those objects.

Another object of the present invention is to provide an intumescent fire-retardant additive composition that when combined with paint resin systems such as oil-based or water- based latex has application to residential, commercial and industrial construction where the additive material is painted on doors, indoor walls, ceilings, flooring, decks, beams, wall barriers and the like. Another object of the present invention is to provide an intumescent fire-retardant additive composition that when combined with a coating material is suitable for a variety of substrates such as iron, steel, stainless-steel, aluminum, titanium, copper, brass, and other metals, wood, ply-wood, chip-board, particle board, and other wood products, plastics, PVC, thermoplastics, fiberglass, epoxies, neoprene, rubber, and the like.

Another object of the present invention is to provide an intumescent fire-retardant additive composition that has application for use in building construction, transportation, telecommunications, utilities, marine construction, chemical and petroleum manufacturing, industrial manufacturing and military applications.

A further object of the present invention is to provide an intumescent fire-retardant additive composition which can be easily mixed, applied, and mass produced in an automated and economical manner and is cost efficient for a variety of applications by the user.

SUMMARY OF THE INVENTION In accordance with the present invention, there is provided an intumescent fire-retardant additive material being in a dry powder form which includes an intumescent base material having a foaming agent, a charring agent, and a blowing agent gas source; a flame spread reduction agent; and refractory fibers. The additive may also have filler and pigment components. The additive composition is in a dry powder form for ease of handling, mixing and incorporating into a coating material at the point of manufacture. The additive material when combined with a flammable coating material, such as PVC, coal tar, epoxy resin, urethane or other paint resin systems, provides for a significant reduction in surface flame spread, protection against radiant heat flux density of up to 600 K /m^? for a duration of 5 minutes, a low rate of thermal transmission and a reduced flammability to the coating material being applied to a substrate.

The fire-retardant additive when combined with a given coating material, (as previously mentioned in the above section) is suitable for a variety of material substrates such as iron, steel, stainless-steel, aluminum, titanium, copper, brass, and other metals, wood, ply-wood, chip-board, particle board, and other wood products, plastics, PVC, thermoplastics, fiberglass, epoxies, neoprene, rubber, and the like.

The fire-retardant additive has many applications for use in construction, transportation, telecommunications, utilities, marine, chemical and petroleum manufacturing and military applications. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

In the present invention, the preferred embodiment of the intumescent fire-retardant additive includes the following:

COMPONENT COMPOUND RANGE (BY WEIGHT)

A. Intumescent Base Material including:

1. A foaming agent such as 25% to 45% ammonium polyphosphate [ ( H₄ ) ₂HP0₄ ] , and potassium tripolyphosphate [K₃P0₄].

COMPONENT COMPOUND RANGE .BY WEIGHT)

2. A charring agent such as 5% to 20% dipentaerythritol (DPE) [C(CH₂OH)₄], chlorinated paraffin, resorcinol, inositol, sorbitol, dextrin, and sorbitol.

3. A blowing agent gas source such as 5% to 20% melamine, urea (NH₂CONH₂), dicyandianide, guanidine, and glycine.

B. Flame spread reduction agent such as 2% to 30% antimony oxide (Sb₂0₃), aluminum trihydrate (Al₂0₃%3H₂O) , zinc borate ( 3ZnO«2B₂0₃) , sodium silicate (Na₂Si0₃), calcium silicate (Ca₂Si0₄), zinc metaphosphate, and potassium metaphosphate. Refractory fibers, such as 0% to 22% aluminum oxide (Al₂0₃), silicon dioxide (Si0₂), ferric oxide (Fe₂0₃), potassium oxide (K₂0), zinc oxide (ZnO), and chromium dioxide (CrO).

COMPONENT COMPOUND RANGE (BY WEIGHT) D. Fillers, such as 0% to 28% calcium carbonate (CaC0₃), calcium silicate and sodium silicate, add bulk.

E. Pigments, such as 0% to 18% titanium dioxide (Ti0₂), and oxalates.

The term plastics or resins include polyvinyl chloride (PVC), polyvinyl acetate, epoxies, urethanes, acrylics, aliphatic polyurethane, plasticizers such as dibutyl phthalate and dioctyl phthalate, and combinations of the foregoing. The additive material of the present invention may be used as an additive to any of the foregoing, when used as a coating material, and thereby substantially increase the fire and heat retardant characteristics of the coating material. The present invention has a number of different applications and uses which determine the particular compounds and formulations used in the fire-retardant composition. For example, when sprayable automobile undercoatings are used, comprising PVC, PVAC, plasticizers. and inorganic additives, the composition of the present invention provides a sprayable material with good mechanical and environmental properties .

The present invention provides fire retardation for exposure to heat at higher radiant fluxes than is provided by previous compositions. In prior compositions, protection against radiant heat flux density of up to 100 kwatt/m² for a duration of up to 100 seconds is provided. In the present invention, protection against radiant heat flux density of up to 600 kwatt/m² for a duration of up to 300 seconds is provided. There is also the additional advantage of a significant reduction in surface flame spread characteristics provided by the present invention. The following examples illustrate the practice of this invention. EXAMPLE I- ADDITIVE TO PVC

One kg of 15% to 20% polyvinyl chloride, of approximately 40% polyvinyl acetate, and 25% to 30% plasticizers is combined with a 400 gm mixture of the following powder ingredients (the mixture): foaming agent (potassium tripolyphosphate 7%), charring agent (chlorinated paraffin 3%), blowing agent (urea 9%), flame inhibitor (zinc borate 2%), pigment (titanium dioxide 4%), fillers (calcium carbonate 5%), and refractory materials (aluminum oxide 1.5%; silicon dioxide 1.0%; ferric oxide 0.4%; potassium oxide 0.2%; zinc oxide 0.2%; and chromium dioxide 0.1%). The composition is applied to a thickness of .020 inches to a steel plate. A propane torch, having a flame temperature in excess of 2,300°F, is applied for five minutes to the coated surface. The composition chars and swells to approximately twenty times its original thickness. The temperature of the steel plate increases at a substantially reduced rate when compared to a coating without the ingredients of the present invention.

EXAMPLE II

One kg of 15% to 20% polyvinyl chloride, polyvinyl acetate of approximately 40%, and plasticizers of 25% to 30% are combined with 200 gm of the mixture of the ingredients listed above in Example I. A steel surface is coated and tested in the same manner as in Example I . After more than

10 minutes of exposure, there is little or no ignition on the coated surface. An untreated coating exposed in a similar manner ignites and burns in less than one minute.

EXAMPLE III

One kg of aliphatic polyurethane is combined with 400 gm of the mixture of the powder ingredients of Example I. The composition is applied to a thickness of .020 inches to a steel plate. A propane torch, having a flame temperature in excess of 2,300°F, is applied for five minutes to the coated surface. The composition chars and swells to approximately twenty times its original thickness. The temperature of the steel plate increases at a substantially reduced rate when compared to a coating without the powder ingredients of the present invention.

EXAMPLE IV

One kg of coal tar epoxy is combined with a 250 gm of the mixture of the powder ingredients of Example 1. The composition is applied to a thickness of .005 inches over previously fire-retardant treated coated cables of varying diameters from 0.5 inches to 2.0 inches. The cables are installed in the top section of an oven, similar to the arrangement prescribed by IEEE383. The oven temperature is raised to 1800°F for an hour, as required by the standard.

The temperature of the cables are monitored at various locations. The results indicate that the temperatures are well within the requirements for in excess of one hour.

APPLICATIONS AND USES OF THE PRESENT INVENTION

The intumescent fire-retardant powder additive material of the present invention can be used in conjunction with a variety of coating materials, as previously mentioned above.

For example, coating materials of PVC having the additive contained therein are used in the transportation industry. The fire-retardant coating material would be used in autos, buses, trucks, cargo ships, and airplanes for coating of vehicular undercarriages, exhaust systems, gas tanks, catalytic converters, hoods, firewalls, engine compartments, cargo liners, engine rooms, and the like.

Another example of an application would be to use the additive for a coating material of coal tars having the additive contained therein in the construction, marine, telecommunication, utilities, petroleum and chemical industries. The coal tar coating material would be used in conditions where there is a high degree of fresh/salt-water corrosion, chemical corrosion, and humidity; such that the coating material would be used on bridges, oil-drilling platforms and rigs, refineries, chemical plants, utility power plants, communication towers, and the like. The coal tar with a fire-retardant additive is designed to maintain flexibility and protection in the most severe environmental and weather conditions.

A further example of an application would be for coating materials such as urethanes, (e.g. aliphatic polyurethane), epoxy resins, paint resin systems having the additive contained therein being used in the construction of residential dwellings, hotels, public accommodations, commercial buildings, public garages, high-rise buildings, condominiums, and the like. These coating materials would be used for the waterproofing of exterior sidings, roofing, interior structures, hung ceilings, wall barriers, and the like. ADVANTAGES OF THE PRESENT INVENTION

Accordingly, an advantage of the present invention is that it provides for a fire-retardant additive product for mixing with a flammable coating material, such as PVC, coal tar, epoxy resin or urethane, to provide an effective fire- retardant coating for a substrate that when used as an additive is able to withstand a continuously maintained temperature as high as 2,000°F, without significantly degrading the environmental and mechanical properties of the substrate being coated. Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that includes a novel combination of an intumescent base material having a foaming agent, a charring agent, and a blowing agent; a flame spread reduction agent; and refractory fibers. The additive may have optional filler and pigment components.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that is in a dry powder form for ease of handling, mixing and incorporating into a coating material at the point of manufacture.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that combines with a flammable coating material, such as PVC, coal tar, epoxy resin, or urethane, to provide a significant reduction in surface flame spread characteristics, protection against radiant heat flux density of up to 600 kw/m² for a duration of 5 minutes, a low rate of thermal transmission and reduced flammability to the coating material being used.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that when combined with a PVC coating material has application in the transportation industry for vehicle under carriages, exhaust systems, gas tanks, engine compartment fire walls, catalytic converters, hoods and floors.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that when combined with an epoxy resin or urethane coating material has application in residential, hotel, commercial office and industrial plant construction where the additive coating material is used as an exterior paint coating which also helps to weatherproof the structure being constructed.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that when combined with a coal tar coating material has application in the marine, telecommunications, utilities, and petroleum industries where the additive coating material is used for bulkheads, cables, conduits, offshore oil drilling platforms, seals, pipeline wraps and chemical storage tanks for the prevention of water, saltwater and chemical corrosion to those objects.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that when combined with paint resin systems such as oil-based or water-based latex has application to residential, commercial and industrial construction where the additive material is painted on doors, indoor walls, ceiling, flooring, decks, beams, wall barriers and the like.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that when combined with a coating material is suitable for a variety of material substrates such as iron, steel, stainless-steel, aluminum, titanium, copper, brass, and other metals, wood, ply-wood, chip-board, particle board, and other wood products, plastics, PVC, fiberglass, thermoplastics, epoxies, neoprene, rubber, and the like.

Another advantage of the present invention is that it provides for an intumescent fire-retardant additive composition that has application for use in building construction, transportation, telecommunications, utilities, marine construction, chemical and petroleum manufacturing and military applications.

A further advantage of the present invention is that it provides for an intumescent fire-retardant additive composition which can be easily mixed, applied, and mass produced in an automated and economical manner and is cost efficient for a variety of applications by the user.

A latitude of modification, change, and substitution is intended in the foregoing disclosure, and in some instances, some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the spirit and scope of the invention herein.

Claims

WHAT IS CLAIMED IS;

1. A fire-retardant material in powder form used as an additive for flammable resins and coal tars used as a coating material for substrates, comprising: a) an intumescent base material having a foaming agent, a blowing agent, and a charring agent; b) a flame spread reduction agent which provides protection against radiant heat flux density of up to 600 kw per square meter for a duration of 5 minutes; and c) refractory fibers in said additive material.

2. A fire-retardant additive material in accordance with claim 1, wherein said foaming agent is ammonium polyphosphate or potassium tripolyphosphate.

3. A fire-retardant additive material in accordance with claim 1, wherein said blowing agent is melamine or urea.

4. A fire-retardant additive material in accordance with claim 1, wherein said charring agent is dipentaerythritol (DPE) or polyol.

5. A fire-retardant additive material in accordance with claim 1, wherein said flame spread reduction agent is selected from the group consisting of zinc borate, antimony oxide, aluminum trihydrate, sodium silicate, or calcium silicate.

6. A fire-retardant additive material in accordance with claim 1, wherein said refractory fibers are aluminum oxide and silicon dioxide.

7. A fire-retardant additive material in accordance with claim 1, wherein said refractory fibers are aluminum oxide and silicon dioxide in combination with at least one or more of ferric oxide and titanium dioxide.

8. A fire-retardant additive material in accordance with claim 1, further including a filler component.

9. A fire-retardant additive material in accordance with claim 1, further including a pigment component.

10. A fire-retardant additive material in accordance with claim 8, wherein said filler component is calcium carbonate (CaC0₃).

11. A fire-retardant additive material in accordance with claim 9, wherein said pigment component is titanium dioxide (Ti0₂) .

12. A fire-retardant additive material in accordance with claim 1, which is combined with a coating material.

13. A fire-retardant additive material in accordance with claim 12, wherein said coating material is PVC, epoxy resin, coal tar, urethane or a paint resin system.

14. A fire-retardant additive material in accordance with claim 1, wherein said foaming agent of said intumescent base material is in the range of 25% to 45% by weight.

15. A fire-retardant additive material in accordance with claim 1, wherein said charring agent of said intumescent base material is in the range of 5% to 20% by weight.

16. A fire-retardant additive material in accordance with claim 1 , wherein said blowing agent gas force of said intumescent base material is in the range of 5% to 20% by weight.

17. A fire-retardant additive material in accordance with claim 1, wherein said flame spread reduction agent is in the range of 2% to 30% by weight.

18. A fire-retardant additive material in accordance with claim 1, wherein said refractory fibers are in the range of 0% to _22% by weight.

19. A fire-retardant additive material in accordance with claim 1, wherein said refractory fibers are in the range of 1/2 ounces to 3 1/2 ounces for each pound of intumescent base material.

20. A fire-retardant additive material in accordance with claim 8, wherein said filler component is in the range of 0% to 28% by weight.

21. A fire-retardant additive material in accordance with claim 9, wherein said pigment component is in the range of 0% to 18% by weight.