KR100571684B1 - Stable expandable flame retardant paint under tropical conditions - Google Patents

Abstract

The present invention relates to an insulating layer forming flame retardant paint based on a carbon forming material, a film forming binder, a foaming agent, and conventional auxiliaries and additives, which form a foam layer in a fire, wherein the paint is a melamine salt and / or guanidine salt as a blowing agent. And / or microencapsulated melamine.

The insulating layer forming flame retardant paint according to the present invention is particularly stable under tropical conditions (relative humidity of 100% or less, about 75 ° C). In other words, very little NH ₃ is emitted.

Description

Expandable Flame Retardant Paint Stable Under Tropical Conditions

The present invention relates to an insulating layer forming flame retardant paint based on a carbon forming material, a film forming binder, a foaming agent, and conventional auxiliaries and additives which form a foam layer in a fire.

Insulating layer forming flame retardant paints, also called foaming paints, prevent foaming of heat into steel structures, ceilings, walls, cables and pipes as a result of the fact that they foam by the action of proper heat in the event of fire, and as a result of the foaming of such flame retardant paints; At least delay.

U.S. Patent No. 4,965,296 describes a flame retardant material consisting of a flame retardant paint and a conductive material. Flame retardant paints include bubble forming and carbon forming materials, gas generating compounds, film forming binders and corresponding solvents. If desired, conventional additional ingredients may be present.

U.S. Patent No. 4,879,320 describes a flame retardant composition similar to the above document, but a ceramic fiber material is added in place of the conductive material.

U. S. Patent No. 5,225, 464 describes an aqueous expandable formulation based on the reaction product of phosphoric acid, melamine and monoammonium phosphate, which formulation is improved with pentaerythritol, chlorinated hydrocarbons and further compounds, in particular polyvinyl acetate. It is reported to provide an intumescent paint.

In the "Fire Retardants Formulations Handbook", author: Vijay Mohan Bhatnagar, 1972, a number of expandable formulations are described.

German Patent Publication No. 42 18 184 A1 discloses at least one NCO prepolymer (a) and at least two primary and / or water-soluble and / or water-dispersible, urethane groups and blocked isocyanate groups in the presence of component (b). Or an aqueous binder mixture consisting of an aqueous solution and / or dispersion of a combination of polyamine component (b) comprising at least one aliphatic (alicyclic) polyamine having a secondary amino group.

German Patent Publication No. 43 43 668 discloses at least 4 to 25% by weight of film forming binder, 10 to 4% by weight of ammonium polyphosphate, 8 to 40% by weight of one or more substances carbonized under the action of heat, 6 to 25% by weight of blowing agent, A foamable flame retardant paint comprising 0 to 5 wt% dispersant and 0 to 25 wt% filler is described.

A disadvantage of the flame retardant paints described above is that they usually contain halogen or do not have a sufficient degree of widespread use.

In particular, for formulations containing melamine as blowing agent, these formulations have been found to release relatively large amounts of ammonia (NH ₃ ) at elevated temperatures and high atmospheric humidity, eg tropical conditions.

Accordingly, it is an object of the present invention to provide an insulating layer-forming flame retardant coating that emits a very small amount of NH ₃ even under high atmospheric humidity and temperature, for example, when considering climatic conditions such as the tropics.

This object is solved by a coating containing an melamine salt and / or a guanidine salt and / or microencapsulated melamine as blowing agent, as an insulating layer forming flame retardant paint of the type described at the beginning of the specification.

The melamine salt is preferably melamine phosphate, melamine cyanurate, melamine borate and melamine silicate, and the guanidine salt is preferably guanidine phosphate.

As mentioned above, microencapsulated melamine is also suitably used in the present invention.

The flame retardant paint forming the insulating layer is preferably 5 to 30 parts by weight of the film-forming binder, 15 to 50 parts by weight of the foamed layer forming material, 5 to 25 parts by weight of the carbon forming material, 5 to 50 parts by weight of the melamine salt and / or guanidine salt. Parts and 10 to 50 parts by weight of conventional auxiliaries and additives.

The flame retardant paint forming the insulating layer is particularly preferably 10 to 20 parts by weight of the film forming binder, 25 to 40 parts by weight of the foaming layer forming material, 7 to 15 parts by weight of the carbon forming material, melamine salt and / or guanidine salt 7 to 40 parts. 20 parts by weight and 20 to 40 parts by weight of conventional auxiliaries and additives.

The flame retardant paint forming the insulating layer is preferably a film forming binder, which includes vinyl acetate homopolymer; Copolymers of vinyl acetate, ethylene and vinyl chloride; Copolymers of vinyl esters of long chain branched carboxylic acids with vinyl acetate; Copolymers of vinyl acetate and di-n-butyl maleate; Copolymers of vinyl acetate and acrylic esters; Copolymers of styrene and acrylic esters and / or acrylic ester copolymers; Vinyl toluene / acrylate copolymer; And styrene / acrylate polymers.

The flame retardant paint forming the insulating layer preferably contains, as the foam layer forming material, an ammonium salt of phosphoric acid and / or polyphosphoric acid.

The flame retardant paint forming the insulating layer preferably contains carbohydrates as the carbon forming material.

Carbohydrates which are preferably used are pentaerythritol, dipentaerythritol, tripentaerythritol and / or pentaerythritol polycondensates.

The flame retardant paint forming the insulating layer preferably contains glass fibers, mineral fibers, kaolin, talc, alumina, aluminum hydroxide, magnesium hydroxide, precipitated silica, silicates and / or powdered cellulose.

It is preferable that the flameproof coating which concerns on this invention which forms an insulating layer does not contain a halogen.

The flame retardant paint according to the invention forming the insulating layer releases NH ₃ below 550 ppm during storage under high (atmosphere) humidity [relative humidity of less than 100%] and elevated temperatures (about 75 ° C.).

Flame retardant paints (expandable paints) according to the invention are used in the form of paints which can be coated by brushing, spraying or rollers to protect various surfaces, preferably steel, wood, electronic cables and pipes.

In the following examples, an intumescent paint is prepared and applied to a standard steel sheet and the effect thereof is evaluated. Insulation force is tested according to DIN 4102, part 8 (1986). Before testing the dielectric force, the water resistance test is carried out by storing the coated steel sheet for 4 weeks at 40 ° C. and 95% atmospheric humidity in the conditioning room.

The following products are used in the examples:

^R Pliolite [Solid, manufactured by Goodyear / France]

This is a thermoplastic resin of Newtonian behavior based on vinyl toluene / acrylate copolymer.

^R Hostaflam AP 462 from Clariant GmbH, Frankfurt am main

This is a microencapsulated ammonium polyphosphate based on ^R Hosttaflam AP 422, containing about 10% by weight capsule material comprising melamine / formaldehyde resin prepared and cured according to EP 0 180 795.

^R Hostaplam AP 422 from Hoechst AG, Frankfurt am main is a free flowing, powdery, poorly water soluble ammonium polyphosphate of formula NH ₄ PO ₃ , wherein n is from 20 to 1000, in particular from 500 to 1000. The fraction of particles having a particle size of less than 45 μm is at least 99%.

Example 1 (Comparative)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

38 parts by weight of ^R Hostaflam AP 462;

10 parts by weight of ^R pliolite (solid);

Melamine 8 parts by weight;

8 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residual amount up to 100 parts by weight of thickener, plasticizer and solvent.

In the flame test of coated sheets according to DIN 4102, they are classified as flame class F 30. After storage in the conditioning chamber, the flame classification is likewise F 30.

Example 2 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

^R hostaplam AP 462 38 parts by weight;

10 parts by weight of ^R pliolite (solid);

22 parts by weight of melamine phosphate;

8 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residue to 100 parts by weight of thickeners, plasticizers and urine.

Example 3 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

^R hostaplam AP 462 38 parts by weight;

10 parts by weight of ^R pliolite (solid);

16 parts by weight of melamine cyanurate;

8 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residual amount up to 100 parts by weight of thickener, plasticizer and solvent.

Example 4 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

^R hostaplam AP 462 38 parts by weight;

10 parts by weight of ^R pliolite (solid);

12 parts by weight of melamine borate;

8 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residual amount up to 100 parts by weight of thickener, plasticizer and solvent.

Example 5 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

^R hostaplam AP 462 38 parts by weight;

10 parts by weight of ^R pliolite (solid);

21 parts by weight of melamine silicate;

8 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residual amount up to 100 parts by weight of thickener, plasticizer and solvent.

Example 6 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

^R hostaplam AP 462 38 parts by weight;

10 parts by weight of ^R pliolite (solid);

10 parts by weight of guanidine phosphate;

8 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residual amount up to 100 parts by weight of thickener, plasticizer and solvent.

Example 7 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

27 parts by weight of ^R hosttaflame AP 422;

20 parts by weight of ^R Mowilith DM 510;

39 parts by weight of melamine phosphate;

13 parts by weight of dipentaerythritol;

5 parts by weight of titanium dioxide and

20 parts by weight of thickener, plasticizer and water.

Example 8 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

27 parts by weight of ^R hosttaflame AP 422;

20 parts by weight of ^R Mowillitte DM 510;

18 parts by weight of microencapsulated melamine;

13 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residual amount up to 100 parts by weight of thickener, plasticizer and solvent.

Example 9 (Invention)

The following materials are mixed continuously and then applied appropriately to the sheet to be tested:

^R hostaplam AP 462 38 parts by weight;

10 parts by weight of ^R pliolite (solid);

8 parts by weight of microencapsulated melamine;

8 parts by weight of dipentaerythritol;

8 parts by weight of titanium dioxide and

Residual amount up to 100 parts by weight of thickener, plasticizer and solvent.

All sheets tested in Examples 2 to 9 achieve flame classification F 30.

NH ₃  Measurement of emission

To measure the NH ₃ release, the dried sample sheet is placed in a closed glass system. The glass system includes a 500 ml glass container and a glass cover with two tabs. In order to simulate atmospheric humidity (relative humidity of about 100%), a glass tray containing 10 ml of tap water is present in the glass system. The glass system is placed in a reduced pressure drying oven at 75 ° C. with one tab sealed. The remaining tabs are likewise sealed after 10 minutes in a drying oven. The residence time of the vessel in the drying oven is 120 minutes. The vessel is then retrieved from the drying oven and a Drager tube is fitted to one tab using an adapter. Nitrogen is fed to the second tap at a rate of 5 l per hour. The vessel is blown for 30 minutes and the amount of ammonia released is read directly on the laser tube.

The measurement results described above are shown in FIG. To 20 fold less) NH ₃ .

FIG. 1 shows a comparison of the amount of NH ₃ released from the steel sheet coated with comparative paint (Example 1) and the steel sheet coated with paint of the present invention (Examples 2 to 9) under the same conditions. .

Claims (10)

An insulating layer forming flame retardant paint based on a carbon forming material, a film forming binder, a foaming agent, and conventional auxiliaries and additives for forming a foam layer in a fire, 5 to 30 parts by weight of the film-forming binder, 15 to 50 parts by weight of the foam layer forming material, 5 to 25 parts by weight of the carbon forming material, 5 to 50 parts by weight of the melamine salt, guanidine salt, microencapsulated melamine or a mixture thereof and the usual An insulation layer forming flameproof coating containing a phosphorus adjuvant and 10-50 weight part of additives. The flame retardant paint of claim 1, wherein the melamine salt is melamine phosphate, melamine cyanurate, melamine borate and melamine silicate and the guanidine salt is guanidine phosphate. The film forming binder according to claim 1, wherein 10 to 20 parts by weight of the film forming binder, 25 to 40 parts by weight of the foam layer forming material, 7 to 15 parts by weight of the carbon forming material, melamine salt as the blowing agent, guanidine salt, microencapsulated melamine or An insulating layer-forming flame retardant paint comprising 7 to 40 parts by weight of a mixture thereof and 20 to 40 parts by weight of a conventional auxiliary agent and additives. The method of claim 1 or 2, further comprising: a vinyl acetate homopolymer; Copolymers of vinyl acetate, ethylene and vinyl chloride; Copolymers of vinyl esters of long chain branched carboxylic acids with vinyl acetate; Copolymers of vinyl acetate and di-n-butyl maleate; Copolymers of vinyl acetate and acrylic esters; Copolymers of styrene and acrylic esters, acrylic ester copolymers, or both; Vinyl toluene / acrylate copolymer; Or an insulating layer-forming flame retardant paint containing a styrene / acrylate polymer as a film-forming binder. The insulating layer forming flame retardant coating according to claim 1 or 2, wherein an ammonium salt of phosphoric acid, polyphosphoric acid or both is present as the foam layer forming material. The insulating layer forming flameproof coating of Claim 1 or 2 in which a carbohydrate exists as a carbon formation material. The flame-retardant paint for forming an insulating layer according to claim 6, wherein the carbohydrate used is selected from the group consisting of pentaerythritol, dipentaerythritol, tripentaerythritol, and pentaerythritol polycondensate. The method according to claim 1 or 2, wherein at least one substance selected from the group consisting of glass fibers, mineral fibers, kaolin, talc, alumina, aluminum hydroxide, magnesium hydroxide, precipitated silica, silicates and powdered cellulose is present as an adjuvant and additive. Flame retardant paint for forming insulation layers. The insulating layer forming flameproof coating of Claim 1 or 2 which does not contain a halogen. The flame-retardant paint according to claim 1 or 2, wherein NH ₃ is released to less than 550 ppm when stored under conditions of high humidity (relative humidity of 100% or less) and elevated temperature (about 75 ° C).