FI86738B - AKTIVBRANDSKYDDSMEDEL. - Google Patents

Description

86738

Active Fire Protection

The invention relates to a mixture which acts as a coating or adhesive for a product, which at the same time protects the product from fire as a layer which prevents heat transfer and ignition and, above all, is cohesive in the event of fire, as defined in the preamble of appended claim 1. Such a fire-protected product is most commonly a board, such as a building board, an insulation board or a board used for cladding, or a sandwich building element. However, the mixture can be used with almost any material or structure, for example mineral, concrete, metal, wood, plastic, mineral wool and paper surfaces, as well as plastic-based insulation surfaces.

The insulating ability of known fire-resistant sheets or elements is based primarily on the ignition resistance of the material and secondarily on its thermal insulation. Such materials work quite well in terms of fire, but their structure is brittle, so the protective effect only lasts for a relatively short time and the material does not withstand shocks, compression or bending afterwards.

25 For example, paint-like coatings are used which are brushed or sprayed on the desired surface. Some non-combustible filler, such as fine crushed stone, slag, asbestos, fibers, etc., is often added to the coating. By the cladding time is meant the time in minutes that the test piece takes in the combustion test as heat passes through the test piece 35 until the opposite surface has reached a certain temperature.

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Coatings are also known to prevent fire damage due to high temperatures. In addition to their fire-suppressing properties, such coatings also have insulating properties. As an insulating component, it is known to use, for example, water glass, vermiculite, clay, etc. as a filler for the coating, which is pre-expanded and, due to its porous structure, slows down the transfer of heat through the coating.

Although such a coating increases the protective cladding time of the product to be protected, the structure of this coating is also broken and brittle in the event of a fire, and thus cannot effectively act as a heat-insulating layer for a long time because it collapses quickly.

15

Abstract Chemical Abstracts can. 103 (1985), 200124a, SU-1 167 172 discloses a coating with increased strength and containing pumice particles, mineral fibers, water glass and ammonium sulphate. It does not contain blast furnace slag or other slag and thus does not swell under a controlled porous strong layer in the event of a fire, such as the mixture according to the invention.

Abstract Chemical Abstracts can. 81 (1974), 155323d, 25 JP-74 54442 discloses a heat-resistant adhesive containing 20 to 150 parts by weight of blast furnace slag per 100 parts by weight of water glass. The mixture does not aim at an intumescent, heat-insulating protective layer, as in the mixture according to the invention, but at a heat-resistant adhesive layer which binds, for example, a thin steel plate and a glass cloth. The mixture may also contain a mineral powder which still reduces the swelling property.

Abstract Chemical Abstracts can. 84 (1976), 21493η, JP-75 096262 discloses a binder containing silicate solutions 35 and blast furnace slag. The ingredients are mixed, the mixture is heated and then cooled. The binder is used, for example, to join two thin steel plates. The binder mixture is heated during the manufacturing stage, which means that it can no longer swell 3 86738 in a subsequent fire situation. The binder may further contain bentonite, which further reduces the tendency of the water glass to swell.

GB-1 393 246 discloses a mixture containing water glass which acts as an adhesive. The mixture does not contain blast furnace slag, which would allow the mixture to swell in a controlled manner and form a strong bonding surface.

GB-1 525 212 discloses a refractory expandable coating comprising water glass, water, solid water glass particles and slag wool. Slag wool cannot form hydraulic bonds like the blast furnace slag used in accordance with the invention. Thus, slag wool does not strengthen the walls of the water glass pores and does not control the pore swelling.

SU-512 225 discloses a refractory coating composition for wood. It contains 60-70% water glass, a considerable amount, 25-30%, asbestos cement waste, 15-20% granulated blast furnace slag and some carboxymethylcellulose. Due to the large amount of blast furnace slag and the even higher amount of asbestos cement, swelling does not occur, but slag and similarly acting asbestos cement work to improve the adhesive properties. The coating according to the publication does not crack and its coverage and adhesion are good, but no expanded, insulating, reinforced coating is obtained.

SU-1 293 149 discloses an intumescent refractory composition comprising both water glass and blast furnace slag, and in addition approximately the same amount of dome furnace slag as blast furnace slag, and still a substantial amount of neutralizing slurry and asbestos, and some filter compression waste, i.e. cellulose. The purpose of this composition is said to be to increase adhesion and, in addition, to utilize industrial waste and to protect the environment. The grain size of the slag particles is apparently on the order of 150 kg / m 2 and the particle size of the blast furnace slag has not been considered significant. As will be seen below, the grain size of the blast furnace slag used in accordance with the invention is of great importance. The granular fineness should be at least 250 m / kg in order for the slag to activate as the temperature rises above 50 ° C and form bonds at the same time as the water glass particles swell.

It is further apparent from SU-1 293 149 that the expansion index is only 3. As can be seen from the following, the mixture according to the invention achieves a swelling of the order of 14-18 times 10 in a slag: water glass ratio of 0.04-0.08, and the amount of mixture at 4 kg / m 2.

The object of the present invention is to provide a fire protection which increases the ignition resistance and thermal insulation capacity of the product and, above all, at the same time gives good strength to the burnt structure, activating these properties only after a fire situation has occurred.

This is achieved according to the invention by imparting to the mixture acting as a coating or adhesive the features defined in the characterizing part of claim 1. By comparing the proportions of water glass and blast furnace slag or similar slag in the coating or adhesive mixture so that the weight ratio of blast furnace slag to water glass is between 0.005 and 0.3, fully closed and size-adjustable, strong-walled pores in the product coating or product coating or product are obtained. This component ratio of the mixture has surprisingly succeeded in providing an active fire protection which expands considerably in the event of a fire, forming a protective structure which does not crush and thus provides a long passageway and good convection and radiation barrier for heat transfer while maintaining a dense and strong structure for a long time. . When used between different layers, the mixture acts as a lii-35 Mana, which can be used to provide a sandwich structure. In the case of a fire, the adhesive layers of such a sandwich structure swell in the same way as when used as a coating and, due to their intact homogeneous porous structure, increase the strength of the sandwich structure for a considerable time.

5

Similar properties are not found in any known fire protection. Above all, it should be emphasized that the mixture according to the invention, in the event of a fire, when applied to the surface of the product or between different layers, strengthens the cohesiveness of the burnt structure due to the controlled reaction between slag and water glass at elevated temperature.

The invention is thus based on the addition to a water glass, either potassium-15 or sodium-containing water glass, of a controlled amount of slag or the like slag which is inert to said water glass at room temperature. As the temperature rises in the event of a fire, the water glass foams in this mixture and, thanks to the slag, the mixture strengthens the structure formed by the product and the mixture applied as a coating or interlayer. The effect of insulation and strength is regulated by the amount of slag used so that the pores generated in the event of a fire do not explode the broken protective layer.

The sheet or sandwich structure coated with the mixture according to the invention thus expands considerably in the event of a fire, but still retains a dense and strong structure for a relatively long time. The pores of the expanded layer are optimized in size for expansion and strength, and are homogeneous in both size and distribution throughout the insulating layer. The pores are closed and the walls between them can withstand even heavy stress. At the same time, the controlled swelling structure provides a rather long passageway and a good convection and radiation barrier for heat transfer.

The expanded insulating structure does not emit any toxic gases during a fire, which is common with known protective coatings.

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A sheet or sandwich structure coated under normal conditions, i.e. at a normal temperature, is no different from a sheet coated with a conventional mixture or a sandwich structure attached with a conventional adhesive layer.

According to a preferred embodiment of the invention, the proportion of ma slag in the mixture is 0.5 to 13% by weight, in particular 4 to 7% by weight. As the blast furnace slag content increases, the swellability of the mixture decreases while its adhesive effect increases, which requires controlled proportionation to achieve the optimum effect.

The mixture preferably contains a humectant, but works without it due to the moisture contained in the water glass.

15 A humectant is added to achieve a smooth drying process and to improve the thixotropy of the mixture. As the moisture control agent, 0 to 5% by weight of cellulose or a cellulose derivative or 0 to 20% by weight of starch, respectively, is preferably used.

20

The molar ratio of water glass, which means the amount of SiO 2 relative to the amount of Νβ2θ or K 2 O, is preferably between 2.0 and 4.5. The water glass begins to swell when its molar ratio exceeds 0.5. Expansion can only be exploited when the molar ratio of de-1.5 exceeds 1.5 and is most preferred at 2.5. When the molar ratio is above 3.0, the moisture resistance is good.

The slag to be added to the water glass is most preferably ground granulated slag. It should be at least partially vitreous.

The slag is preferably ground to a fineness of 250 to 400 m 2 / kg.

The granulated slag is activated as the temperature rises above about 50 ° C and when the temperature continues to rise it reacts nonlinearly upon activation. This reaction is controllable so that the water glass expands in a controlled manner and the matrix as a whole is reinforced by the reaction products of the slag, forming a homogeneous optically porous structure.

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Crystalline slag is more difficult to obtain such a preferred structure because it requires a lower molar ratio, about 1.5 to 2.5.

5 The dry content of the water glass must be such that it can be applied. Water glass with a molar ratio of 3.2 to 3.4 generally has a dry content of 37%. About 1-3 months after coating, the dry content of the water glass layer is about 70%.

10

The mixture is preferably applied by spraying, brushing or smoothing. The lubricity of the mixture can be affected by controlling the dry content of the water glass, which affects the viscosity, and by adding or decreasing the moisture-15 regulator, which affects the thixotropy.

The mixture may also be in dry form, the water glass content being in dry form, usually in spray-dried form. The dry form of the mixture is a suitable commodity. At time 20, water is added to the mixture.

Additives which improve fire protection and other properties can advantageously be added to the mixture. The fire protection properties can be further improved with, for example, vollastonite, limestone, perlite, vermiculite and various fibrous substances, as well as other fire retardants. The elastic and adhesion properties of the substance as well as the water resistance are also quite freely changeable, as are the rheological properties.

30

The mixture is prepared by mixing blast furnace slag and any other dry substances together and adding the mixture thus formed to a glass of water.

In the following, the mixture according to the invention will be explained in more detail with reference to the accompanying figures, which show the properties of the mixture as different functions.

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Figure 1 shows graphically a schematically illustrated average result of experiments showing the number of times the mixture swells as a function of the slag: water glass ratio for different amounts of water glass per unit area; Fig. 2 shows graphically the increase in the temperature of the surface to be protected as a function of time when the surface is coated with the mixture according to Embodiment 3; and Fig. 3 (prior art) shows graphically the increase in the temperature of the surface to be protected as a function of time when the surface is coated with a known fire retardant paint with the mixture according to Embodiment 4.

The curve in Figure 1 shows the exact choice of slag: water glass ratio.

15

In the region A, where the ratio of slag to water glass is 0 to 0.005, the invention does not work, i.e. the product coated with such a mixture does not survive a fire situation. Large inhomogeneous pores form on the surface and the matrix is brittle.

20

In area C, the invention works, but as the weight ratio of slag to water glass approaches 0.3, its practical value is quite non-existent. When this ratio exceeds 0.15, the expansion decreases so much that the insulating properties are reduced to non-existent. The high slag content gives a very strong matrix because the slag reacts strongly with water glass in a fire situation. The slag content improves the adhesive properties of water glass, i.e. improves adhesion and moisture resistance.

30

In area B, the invention certainly works. Homogeneous pores and a fairly strong matrix are formed in the adhesive layers of the coating or sandwich element.

Area D, where the weight ratio of slag to water glass is between 0.04 and 0.08, is the most preferred area of the invention. The number of swellings is 9 times with a lower amount of water glass (1.5 kg / m 2 plate) and a lower value of the weight ratio, decreasing to 6 times with a higher weight ratio of 0.08. Correspondingly, the amount of swelling is 18 times higher with a higher amount of water glass (4 kg / m 2 plate) and a lower value of slag: water glass ratio, decreasing to 14 with a slag: water glass ratio of 0.08. This illustrates very clearly how by varying the 5 slag: water glass ratio in a fairly narrow range one can either increase the swelling i.e. increase the pore size and decrease the strength or vice versa. The optimum mixture for each product is likely to be found in region D.

The curve in Figure 2 shows the rate at which the temperature of a sheet coated with a coating according to the invention rises in the event of a fire. In about 3 minutes the temperature rises to 100 ° C, but in the next 3 minutes the temperature does not rise significantly. After this temperature stop, the temperature rises quite sharply and reaches a temperature of 300 ° C after 20 minutes from the beginning of the experiment. Said temperature stoppage is due to the swelling of the mixture, which at the same time increases the insulating capacity of the coating.

20 The three different curves in the figure refer to the temperature values taken from the "cold" surface of the test piece at three different points.

The curves in Figure 3 show the same as the curves in Figure 2. However, the measurements have been made on a test piece coated with a known fire retardant paint. Here, the temperature of 100 ° C is reached in about 2 minutes and after 3 minutes the temperature is about 110 ° C, after which it rises considerably steeper than in the previous case and reaches the temperature of 300 ° C after less than 9 minutes.

The mixture according to the invention is preferably used as an adhesive between the plates to provide a strong sandwich element. Suitable boards are, for example, fiber cement, gypsum cement-35 and the like, and various substrates such as mineral, concrete, metal, wood, plastic, mineral wool, plastic-based insulation surfaces and paper surfaces. The scope of the invention is very wide.

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In the event of a fire, the adhesive expands 2 to 40 times depending on its slag: water glass ratio and its initial layer thickness. The protective cladding time thus increases up to five times. After the standard combustion test, the plate structure is still 5 cohesive. The swollen layer consists of small closed and evenly distributed pores. Their size and amount depends on the slag: water glass ratio. The pore structure is thus precisely controllable between the slag content extremes shown in Figure 1.

10

When applied as a coating to the surface to be protected, the mixture acts in a manner similar to that used as an adhesive. It binds well the filler added to it, which depending on the application can be, for example, pigment, fine crushed stone, 15 different pozzolans, fibers. The filler strengthens the surface, gives the desired appearance and does not prevent the layer from swelling in a fire situation. As it expands, the thickness of the coating increases by about 5-10 times and the protective coating time by about 3-4 times. The burnt surface layer is small pores and cannot be easily removed by scraping.

In the following, the invention will be explained in more detail by means of a few preferred embodiments. In the examples, the water glass has a dry content of 37% by weight and a molar ratio of 3.2.

25

Example 1

A sandwich structure was prepared consisting of two 60x60x4 mm cellulose cement boards (LUJA board) and a mixture placed between them as an adhesive, the composition of which was:

Water glass: 94.8% by weight

Slag: 4.7% by weight

Cellulose: 0.5% by weight 35 Molar ratio: 3.3

Amount of mixture applied to the plate: 2.25 _kg m ^. plate 11 B 6 7 3 8

The thickness of the structure in the normal state was 9.3 mm, i.e. the thickness of the adhesive layer was 1.3 mm.

The structure was fired according to the standards SFS 4193 and NT FIRE 003-5 ti. As a result of the firing, the protective cladding time was found to be 33 min and the thickness of the structure varied between 16 and 22 mm.

Thus, during firing, the thickness of the adhesive layer had increased to an average of 20 to 8 = 12 mm, i.e. about 10 times. 10 After firing, the sandwich structure was cohesive and strengthens the delta even so inexpensively that it could withstand the weight of one person.

Example 2 A similar experiment was performed in which the composition of the adhesive mixture was:

Water glass: 92.2% by weight

Slag: 7.3% by weight Cellulose: 0.5% by weight

Molar ratio: 3.3

Amount applied to the plate: 1.5 _kg m ^. plate 25 Equivalent results: Protective cladding time = 25 min

Glue thickness increase = 6-10 mm Thus, the thickness increase of the adhesive layer was about 6 times. The strength of the structure after burning was the same as in Example-30 cat 1.

Example 3

A fire protection combination was prepared in which a 60x60x4 mm cellulose cement board was brushed on another large surface with a mixture of: 12,86738

Water glass: 90.5% by weight

Slag: 9.0% by weight

Cellulose: 0.5% by weight

Molar ratio: 3.3 5 Amount applied to the plate: 2 kg m ^. plate

The total thickness of the brushed sheet in the normal state was 4.5 mm, i.e. the thickness of the coating was 4.5 to 4 = 0.5 mm.

10

The board was fired according to the previous standards, as a result of which it was found that the protective coating time was approx. 19 min and the increase in the thickness of the coating was 8 - 4 = 4 mm, i.e. 8-fold. The swollen layer could not be removed by scraping without 15 tools.

During firing, the following visual observations were made: 9 min: swelling started 20 12 min: outer surface starts to darken from the edges 20 min: burning stopped - no cracks - coating small porous and intact - coating cannot be removed by scratching with fingers 25

Figure 2 shows the increase in the surface temperature of this plate as a function of the burning time.

Example 4 (Prior Art) For comparison, an experiment according to Example 3 was performed using a commercially available fire-retardant paint having a consumption of 0.72 kg_m ^ as a coating. plate 35 Coating thickness before firing: 0.5 mm

Coating thickness after firing: not determinable Coating time: approx. 9 min (difficult to determine) 13 86738

During burning, the following visual observations were made: 1.3 min: starts to smoke 5 min: outer surface darkens 5 - plate bent a lot - smoking quite strong 9 min: burning stopped - no cracks - inner surface (fire retardant paint) completely blackened and brittle, 10 removable by fingers.

Figure 3 shows the increase in the surface temperature of this test plate as a function of the burning time.

Claims (11)

14 86 738 1. A composition comprising a product comprising a product or a mixture of products and a shape for a branded product and a branded product, in which the composition is of interest 25 The weight of the product and the wool glass are 0.005 and 0.3 for the brand situation in which the product is used, the starch of the product in the form of a product or the product of the product finhet head min 250 m / kg. A mixture as a coating or adhesive for protecting a product in the event of fire as a heat transfer and flame retardant layer, the mixture comprising water glass and blast furnace slag as main components, characterized in that the weight ratio of blast furnace slag to water glass is between 0.005 and 0.3, closed and , to provide strong-walled pores in a controlled manner to the coating of the product or to the air layer or layers of the product in the event of a fire and that the blast furnace slag is granulated or pelletized and ground to a fineness of at least 250 m2 / kg. 2. A composition according to claim 1, comprising at least 0.005 and 0.15, said 0.04 and 0.08. Mixture according to claim 1, characterized in that said weight ratio is between 0.005 and 0.15, preferably between 0.04 and 0.08. 3. A composition according to claim 1 or 2, which comprises a bulk core of 250 and 400 m / kg. 16 86738 Mixture according to Claim 1 or 2, characterized in that the grain size of the blast furnace slag is between 250 and 400 m 2 / kg. 20 4. The composition comprises a composition according to claims 1-3, the composition of which comprises 0-5% by weight of cellulose or cellulose derivatives. Mixture according to one of Claims 1 to 3, characterized in that the mixture contains 0 to 5% by weight of cellulose or cellulose derivative. 5. The composition of the composition according to claims 1-4, the composition of which comprises a composition of 0-20% by weight of starch or a mucilage function, exempt alginat. Mixture according to one of Claims 1 to 4, characterized in that the mixture contains 0 to 20% by weight of starch or a similar humectant, for example alginate. 6. A composition according to claim 4, comprising 10 to 10% by weight of the composition, 3.5-9% by weight of the weight and 0.5-2% by weight of the cellulose. Mixture according to Claim 4, characterized in that the mixture contains 89 to 96% by weight of water glass, 3.5 to 9% by weight of blast furnace slag and 0.5 to 2% by weight of cellulose. 7. A composition having the form of a patented patent, the composition of which is provided with a water content of between 2.0 and 4.5. Mixture according to one of the preceding claims, characterized in that the molar ratio of water glass is between 2.0 and 4.5. 8. The composition of the composition of the patent, the composition of which comprises the composition, the wattage glass and the tear form, the composition of the spray form 20. Mixture according to one of the preceding claims, characterized in that the mixture is a dry mixture whose water glass content S 6 7 3 8 is in dry form, preferably in spray-dried form. 9. A composition comprising a patented composition, the composition of which comprises the brand name and the other preferred composition of the tulle, lime solids, lime, perlite, vermiculite and / or mineral oil. Mixture according to one of the preceding claims, characterized in that the mixture contains additives which improve fire protection and other properties, such as vollastonite, limestone, perlite, vermiculite and / or various mineral fibers. 10. A composition having the form of a patent, comprising the same genome as a blend mass and, if appropriate, a blanket of a substance and a blanket of the image and the wattage. Mixture according to one of the preceding claims, characterized in that it is prepared by mixing blast furnace slag and any other dry substances and adding the formed mixture to a glass of water. Sandwich structure or coated sheet, characterized in that the sheet is sandwiched between the layer structures of the sandwich element or the sheet is coated with a mixture according to any one of claims 1 to JO. 20 Patentkrav 11. A sandwich structure having a sandwich structure, which can be fitted with a composition according to claims 35 to 10, and which is provided with a sandwich element with a sandwich element or a respectable surface for the ski.