SK65098A3 - Man-made vitreous fibre products and their use in fire protection systems - Google Patents

Abstract

A fire and high temperature protection product is provided which comprises an air laid web of mineral fibres through which is substantially uniformly distributed a particulate endothermic material which has a mean particle size above 5 mu m and is bonded to the mineral fibres of the web and is a material which is a carbonate and/or hydrate and which is heat stable at up to 200 DEG C and decomposes endothermically at a temperature above 200 DEG C.

Description

-1- 11579 Synthetic glass fiber products and their use in fire protection systems

Technical field

The present invention relates to synthetic glass fiber (MMVF) products which are designed to be useful for fire protection.

BACKGROUND OF THE INVENTION

Many fire protection products depend, at least in part, on the endothermic properties of any component in the product to provide fire protection. For example, gypsum is calcium sulfate hydrate. When a high temperature flame is applied to one surface of the gypsum board, the heated gypsum decomposes by heat absorption and releases water. Accordingly, the front of the flame will gradually pass through the thickness of the plate with the temperature on the side remote from the flame maintained at 100 ° C or less.

Since the efficacy of any product produced using an endothermic material is proportional, inter alia, to the amount of endothermic material, it is desirable for the product to have a high concentration of endothermic material. For example, gypsum board generally consists almost entirely of gypsum. Unfortunately, such materials are physically very weak.

CH 382 060 suggests that certain endothermic materials are contained in MMVF products. A product is mentioned which allegedly contains 25 to 30% by weight of glass fibers and 70 to 75% by weight of diatomaceous earth (diatomaceous earth) bound to the fibers by means of a phenolic binder. Apparently it is produced by introducing diatomaceous earth into a preformed structure.

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It is difficult to introduce inorganic particulate material in a preformed MMVF product in a satisfactory manner. For example, when the inorganic additive is sufficiently finely ground, it is possible to introduce the powder by injecting it into the structure, but it will then be dusted again from the structure. It is also possible to impregnate the structure with a slurry of finely ground dust, but this must then be dried and this is not economical.

To date, as we are aware, the products described in CH 382 060 have not been successfully commercialized. This is probably due, in part, to the fact that the endothermic material has always been very finely ground to allow its introduction into the preformed structure so that it is not adequately bound to it.

Many binders that are suitably used for MMVF products need to be heated to a high temperature, for example 200 ° C or higher, to cure them. Thus, endothermic materials having an endothermic decomposition temperature well below 200 ° C (such as diatomaceous earth) are likely to undergo decomposition during curing.

It would be desirable to be able to combine the known properties of an airlaid synthetic glass fiber structure with fire protection properties of endothermic materials without causing manufacturing difficulties and other disadvantages of known products such as described in CH 382 060.

SUMMARY OF THE INVENTION

The fire protection material of the present invention includes an airlaid MMVF fiber structure in which a particulate endothermic material in which the endothermic material has a particle size above 5 μη is substantially uniformly distributed and is attached to synthetic glassware.

-311579 fibers A is a carbonate or hydrate material and the particles are thermally stable at temperatures up to 200 ° C and endothermally decompose at temperatures above 200 ° C.

The particulate endothermic material must be thermally stable at temperatures up to 200 ° C. That is, it must not undergo substantial endothermic decomposition at temperatures of 200 ° C and below, preferably 240 ° C or below. Thermal stability at temperatures up to 200 ° C can be achieved in various ways. For example, the material selected may be such that it does not undergo any endothermic decomposition at temperatures up to 200 ° C. In this way, it may be exposed to high temperatures but retain its ability to degrade endothermically when a particular fire protection product is in use.

Alternatively, particulate materials may be used in which the particles tend to initiate endothermic decomposition below 200 ° C, but which are provided in such a form that they do not undergo endothermic decomposition at temperatures above 200 ° C. In this way, they also retain their ability to degrade endothermically when a particular fire protection product is used. Such materials can undergo small amounts of decomposition at temperatures up to 200 ° C, but do not undergo substantial decomposition and are therefore thermally stable.

Preferred materials release carbon dioxide and / or water of crystallization only at temperatures above 200 ° C. Suitable materials are magnesium hydroxide, calcite (calcium carbonate), dolomite, siderite, aragonite, magnesite, brucite, magnesium carbonate, barium carbonate, barium hydroxide, ferrous hydroxide, pyrite and silicon-water-crystallization compounds which do not release any water at temperatures up to 200 ° C. C.

The particle size of the endothermic material must be above 5 gm. According to this normally 90% by weight of these particles above 5 μια. The particle size is preferably at least 90% above 10 gm,

-411579 more preferably at least 90% above 15 μτα. For materials which do not undergo any decomposition below 200 ° C, it may be at least 90% below 200 μm, for example at least 90% below 100 μπι. Expressed as an average particle size, the preferred ranges are 5 to 10 to 100 μτα, preferably 10 to 70 μπι, most preferably 15 to 50 μτη. An average particle size of 15 to 50 μπι, often around 35 μπι, is often satisfactory.

Alternative materials are those which tend to release carbon dioxide and / or (particularly) water of crystallization at temperatures below 200 ° C, but which are maintained in such a form that the release of carbon dioxide and / or water is minimized. For example, materials having a decomposition temperature between 150 ° C and 200 ° C, for example from 180 ° C to 200 ° C, may be provided in the form of particularly coarse particles. Surprisingly, we find that materials of this type in the form of coarse particles can withstand temperatures up to 200 ° C, and often up to 240 ° C, without substantial decomposition by releasing water of crystallization and / or carbon dioxide. Preferred materials of this kind are those which release water of crystallization, for example, aluminum hydroxide, which is used in the form of fine grains, loses all of its crystallization water at about 185 ° C.

For these materials, average particle sizes of at least 100 μπι, often at least 500 μπι, and even up to 3 mm, for example from 0.5 to 1.5 mm, are suitable.

Materials that release carbon dioxide at temperatures below 200 ° C when in the form of fine grains can often be provided in the form of coarse grains to make them thermally stable at temperatures up to 200 ° C in the same way as materials that release crystallization water .

One preferred class of materials is that which releases carbon dioxide, such as calcium carbonate, and especially those which release carbon dioxide at temperatures above 400 ° C and preferably above 600 ° C.

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For example, calcium carbonate releases carbon dioxide endothermically at temperatures ranging from 700 ° C to 1000 ° C.

Yet another class of materials is the class of crystalline materials that release water of hydration at temperatures above 200 ° C, preferably above 240 ° C, for example 270 ° C to 370 ° C or higher.

Materials or mixtures of materials having different endothermic reactions at two or more temperatures are highly desirable because they extend the fire resistance over a wide range. For example, a mixture of hydrate and carbonate is desirable.

It is desirable that a particular material, or each material in a particular composition, have as high endothermic energy as possible. Some materials that could have high endothermic energy are excluded because they decompose completely at less than 200 ° C. Magnesium hydroxide is a particularly preferred material because it has a high endothermic energy and is stable at 200 ° C and is conveniently available in a coarse particle size.

The particle size of the endothermic material should be as thick as reasonably possible to allow good bonding of the endothermic material to a particular structure without the need for a large amount of binding agent. For example, a surface area of 1 gram of 1 µπι filler composition is typically about 50 times the surface area of 1 gram of 50 µπι filler. Thus, a 50 μπι filler requires far less binder for satisfactory binding properties than a 1 μπι filler. In the present invention, using a relatively coarse endothermic material, it is possible to maintain good bonding by using an amount of binder that is not unacceptable greater than the amount that would be used in the absence of the endothermic material. For example, the dry weight of the binder is typically in the range of 1 to 3% in a traditional MMVF product, and in this invention good bonding can be achieved when

-611579, the amount of binder is about the same, Si is no more than 50 to 100%, for example in the range of 2 to 6% by weight of the product.

The present invention is particularly useful when particulate abrasive, but can be used for softer, less abrasive particulate materials.

It is essential that the MMVF product be bound to a particular structure in order to have little or no dusting of the product from the structure during shipping and handling. Very small amounts of dusting are acceptable since the product may be unacceptable on any surface with a fire-resistant and temperature-stable coating such as aluminum foil or other coating. A suitable test product satisfactorily coupled is et al, Ann. Occup Hyg .__ ..

but the excess dusting is for determining is whether or not it is that described by Schnieder Volume 37, number 37, pages

631-644, 1993.

The binder composition used to bond the endothermic material to the MMVF product may be any of the binders traditionally used for bonding MMVF products. The amount of binder is generally between 2 and 6% by weight of the product.

The MMVF fiber structure must be air laid, because it is impractical to treat it wet and then dry. As is well known, the air laid MMVF structure has (even after compression) a much lower density than the wet-laid product. For example, a wet-laid structure (excluding endothermic material that also acts as a filler) will always have a density below 300 kg / m ³ , often below 250 kg / m ³ . Impregnation of the preformed fiber structure with an endothermic material provides an uneven or otherwise unsatisfactory product, with more endothermic material adjacent to the lateral inlet than elsewhere. Water-based impregnation is a waste of energy because of the need to dry the material.

The airlaid structure may be formed by application

-711579 mineral melt into a rotating, fiber-forming (spinning) rotor, thereby casting the melt from the periphery as fibers and forming a substantially annular cloud of fibers, spraying the binder into this annular cloud of fibers, entraining the fibers axially from the rotor towards the collector surface; the fiber material and collecting the mixture of fibers and endothermic material on the collecting surface as a structure or belt. The web may be a web of the final refractory product, or more usually, the original structure is laminated to itself and then compressed to form the felt, and it may be this compressed felt that is used as a structure in the refractory product of the invention.

In order for the coarse, particulate endothermic material to be bonded to the structure, it is preferred that the particulate material be coated with the binder material before it is mixed with the MMVF materials. A preferred method of making the product of the present invention comprises forming an annular cloud of MMVF fibers as described above, wrapping the endothermic particulate material with a binder and mixing the particulate material into the fiber cloud, and collecting the resulting mixture on the collecting surface as a structure. Additionally, the binder is typically sprayed into the cloud to increase fiber-fiber bonding.

A preferred method of coating the particulate endothermic material with a binder is to form a slurry of particulate material in the aqueous binder, in which case the particulate material can then be introduced into the annular cloud by spraying. In practice, the slurry will normally contain at least 5% by weight of the slurry of particulate endothermic material, but this amount is often above 10% or even 20%. It can be up to 60%, but it is usually not more than 40%.

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Desirably, the density of the slurry is high, as this increases the penetration of the slurry into the annular cloud. The specific gravity may be at least 1.0 and is usually at least 1.1, preferably at least 1.2 and usually at least 1.3 and often at least

1.4. It is usually below 2, generally below 1.7. In order to facilitate spraying, it is desirable that the slurry be reasonably stable against settling and that the aqueous binder composition therefore preferably comprises a dispersion stabilizer which will limit settling. The dispersion stabilizer may be any suitable viscosifier, but is preferably a colloidal material, since the presence of the colloidal material in the aqueous phase can both limit deposition of the filler and modify the rheology of the slurry to facilitate spraying.

Preferably, the dispersion stabilizer is a clay, and thus the slurry is a slurry of particulate endothermic material having a size above 5 µm, often above 10 µm, and preferably above 30 gm, in an aqueous dispersion of clay particles typically having a size below 5 gm, often below 3 gm. The amount of clay or other colloidal material in the slurry is typically in the range of 0.5 to 10% based on the weight of the slurry, often up to 7%, generally 1.5 to 5%.

The amount of clay, if used, in the air laid product is generally in the range of 0.5 to 3%. The clay may tend to bind and thus serve not only as a dispersion stabilizer but also as a binder. Preferably, however, also organic resin.

A suitable method for spraying such a portion or whole using a slurry of an annular cloud slurry to form a bonded airlaid structure is described in our international publication no. WO97 / 20781,

A suitable device for use in this method is described in our International Publication No. WO 97/32510. W097 / 20,779th

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In yet another aspect of fire protection, the synthetic glass fiber, the endothermic material selected by the present invention, comprises a product bonded structure from which it is divided from magnesium hydroxide and carbonates that do not undergo endothermic decomposition at temperatures up to 200 ° C above 200 ° C. Magnesium hydroxide in ° C and endothermic decompose. Preferably, this structure comprises an amount of at least 5%, preferably at least

10% by weight of the total material.

The endothermic material may be introduced in any suitable size and manner and may or may not be distributed evenly and must or may not be joined. Preferably, it is evenly distributed and joined and is in the form of particles above 5 μη, often more than 10 μη.

In all aspects of the invention, the amount of endothermic material is usually in the range of 5 to 50%, e.g. 25 to 30%.

The refractory products of the present invention may be in the form of boards, mats, pipes or granules. When in the form of plates, they can be provided in the form of a laminate between steel sheets. Products of this type are particularly suitable for use as fire doors. The fibrous products may have a density ranging from 10 to 300 kg / m ³ .

The mineral fibers of the product may be made of glass, rock, stone or slag, but are preferably made of rock, stone or slag because of the exceptional fire resistance of these fibers.

The spinner is a spinner type of the type described in EP 530 843 or of the Downey type as described in U.S. Pat. Nos. 2,944,284 and 3,343,933, but preferably the rotor is mounted about a substantially horizontal axis and It has a fixed point and is designed to receive the melt applied to the perimeter

-1011579 and casting mineral fibers from the perimeter. Most preferably it is a cascade device comprising 2, 3 or 4 such rotors. A suitable cascade spinner is described in, for example, WO92 / 06047. When the endothermic particulate material is applied by spraying the slurry, the slurry may be sprayed coaxially from, for example, the last spinning rotor and / or the penultimate spinning rotor, and if desired, the binder may be coaxially sprayed from the second spinning rotors. Accordingly, the annular cloud of filaments into which the slurry is deposited will not be a real ring, but will instead merely extend forward from the outermost portions of the cascade.

BRIEF DESCRIPTION OF THE DRAWINGS

The following is an example of the present invention. In this example, a spinner is used, which is shown in the following drawings, in which:

Fig. 1 shows a cross-section of the rotor forming part of the spinner. Fig. 2 is a front view of another rotor according to the present invention showing an alternative fluid outlet.

DETAILED DESCRIPTION OF THE INVENTION

Fig. 1 shows a fixed rotor 1 of a kind used in a cascade spinner mounted on a rotary shaft 1. Fluid distribution means 1 are fastened to the rotor. having a distribution surface 11. The substantially frustoconical surface U is a concave surface containing a plurality of grooves 1A, six of which are shown. The distribution surface has a short edge 12 and a long edge 14, the long edge 14 is opposite the short edge 12- The long edge 14 is at a radius of 0.6 R, where

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R is the rotor radius. The rotor 1 is supported on the rotary shaft 3 by roller bearings 22. The non-rotating fluid flow channel 6 is supported on the bearings 10, usually the roller bearings, between the rotating shaft 3 and the non-rotating fluid flow channel 6. The non-rotatable fluid flow channel 6 leads to and is attached to the fluid flow outlet 2, which is non-rotatable. This has two (or more) radially extending discharge openings. The radially extending discharge openings may be angled backward at an angle of 10-45 ° to ensure that the discharged fluid meets the surface, distributing in the smallest possible radius.

In use, the particulate solids suspension in the aqueous phase is delivered (delivery means (not shown)) to the fluid flow passage 5 which extends through the rotating shaft 31 and to the fluid flow exit. The suspension is then passed through the apertures.

The partially atomized suspension passes through the air gap in the direction of the arrows and onto the distribution surface 11. The rapid rotation of the fluid distribution means 18 induces a radial outward movement of the suspension led by the grooves 18 to the end points 22 of the grooves at the edge 14. thrown in an atomized form from the distributor surface radially outwardly and forwardly from the rotor.

If any slurry does not move outwardly along the grooves 13, but tends to be a device, it passes along the inlet radially back into the channel 28 into the rotating annular chamber 24. Rotating this chamber induces the suspension to move to the outer wall of the chamber from where it flows along the outlet channel 23 to the distribution surface at its short edge. A seal 34 is positioned between the chamber 24 and the roller bearing 30. Thus, leakage to other regions of the device has been prevented.

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In parallel, the melt is applied to the periphery 22 of the rotor 1, which rotates rapidly and casts the melt from the periphery as a fiber. The fibers are blown forward by conventional air supply means (not shown) in the annular cloud. When the fibers are blown forwards, they encounter an atomized suspension of liquid partitioning means. The suspension and the ingredients it contains penetrate the annular cloud and cover the fibers.

These fibers are then harvested in a traditional manner as a structure comprising a uniformly distributed additive on the collector. The structure (or strip) may be cross-lapped or folded to form a felt, and the product may be compressed and thermally cured in a traditional manner.

Fig. 2 shows an alternative structure for the fluid flow outlet. In this construction, it is in the form of a slot covering about 135 ° of a possible 360 °. The liquid additive flows from the fluid flow channel 5 through the slot 36 and is supplied to the fluid distribution surface. The liquid additive flows through the region The spiral-type fluid pathway results from the rapid rotation of the distribution surface in a clockwise direction. In other embodiments, the rotation may be anti-clockwise. The liquid additive is thus thrown from the long edge 14 of the periphery of the distributor surface substantially upwards through about 135 ° of the periphery of the distributor surface.

Example 1

A suspension of the resol-formaldehyde binder in water is placed in the pulper. A slurry having a specific gravity above 1.1 is produced by mixing with a binder dispersion of particulate magnesium hydroxide with an average particle size of 35 gm. The porridge is blended into

-1311579 fibers at the fiber forming point by the apparatus and process of FIG. 1 as described above. A plate product is formed from the resulting fibers.

The same procedure is carried out without the use of a flame retardant magnesium hydroxide material.

Both the fireproof plate of the present invention (plate A) and the traditional plate (plate B) were subjected to a standard fire test according to ISO 834. The results are shown in Table 1 below. These results show the temperature on the cold side of the plate over a period of time.

Corresponding results indicate a gradual increase in the temperature on the cold side of the plate as a result of the heat passing through the plate. In some products, a very rapid increase in temperature can be observed followed by a very rapid decrease in temperature. This is due to the burning (or burning) of the binder.

This combustion is minimized in plate A of the present invention.

As can be seen from the respective results below, the time to raise the temperature to 190 ° C or greater on the cold side of the board is more than three times longer for board A than board B, confirming the increased fire and glow resistance of the products of the invention. . Poor results are also obtained when magnesium hydroxide with an average particle size of 2 μχα is used.

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Temperature (° C) Plate B Temperature (° C) Plate A O ω cp B o g oo WHAT about 27 23 about 46 42 20 290 47 30 69 40 1 123 50 150 60 152 70 154 80 1 158 90 1 σ> 100

First

rv ace-98

Claims (18)

PATENT CLAIMS 11579 A fire-fighting product comprising an airlaid synthetic glass fiber structure in which it is substantially endothermic greater than 5 particulate, wherein the material has a gm and is bound to and is within the structure and is or is a hydrate and which is 200 ° C and endothermic is an endothermic material; in that said particle average particle size to the synthetic glass is substantially uniformly distributed by the material which is thermally stable at a temperature to decompose at a temperature above 200 ° C. The product of claim 1, wherein the endothermic material is selected from magnesium hydroxide and carbonates which do not undergo endothermic decomposition at temperatures up to 200 ° C and endothermic decompose at a temperature above 200 ° C. Product according to claim 1 or 2, which contains particulate magnesium hydroxide in an amount of at least 5% by weight. Product according to any preceding claim, wherein the endothermic material has an average particle size of 10 to 500 µπι, preferably 10 to 100 µπι. The product of any one of claims 1 to 3, wherein the endothermic material has an average particle size of from 0.5 to 3 mm. The product of claim 5, wherein the endothermic material is aluminum hydroxide. -1611579 The product of any preceding claim, wherein the amount of particulate endothermic material is from 5 to 50% by weight of the product. r The product of any preceding claim additionally comprising a colloidal clay. A product according to any preceding claim having a density of at least 10 kg / m ³ . The product of any preceding claim, wherein the airlaid structure, in the absence of endothermic material, has a density below 300 kg / m ³ . A product according to any preceding claim, made by applying a mineral melt to a rotating spinning rotor (1) and thereby casting the melt from the periphery of the rotor (1) as fibers and forming a substantially annular cloud of fibers, coating the particulate endothermic material with a binder and mixing. wrapping material into a fiber cloud, and collecting the mixture as an airlaid bonded structure, and curing the binder. The product of claim 11, wherein the particulate material is coated with a binder by dispersing it as a slurry in the aqueous binder and spraying the slurry into an annular cloud of primary fibers. 13. A fire protection product comprising a bonded structure of synthetic glass fibers in which it is -16a11579 14th divided particulate characterized by the endothermic material magnesium and endothermic and endothermic s are carbonates, decompose at endothermic and by being selected from particles that do not pass through any particulate hydroxide material at temperatures above 200 ° C 200 ° C. Product by Endothermic Material Fiber Structures. claim 13, in which it is bound to the synthetic glass particles 15th 16th The product of claim 13 or 14, wherein the synthetic glass fiber structure is an airlaid structure. The product of any one of claims 13 to 15, wherein the particulate endothermic material is substantially uniformly distributed throughout the structure of the synthetic glass fibers. 17th The product of any one of claims 13 to 16, wherein the endothermic material comprises magnesium hydroxide. A product according to any one of claims 13 to 17, having any of the additional features set forth in Articles 3 to 5 and 7 to 12.