SK227792A3 - Transparent heat resistance glazing panel and the method of its manufacturing - Google Patents

Description

(57) The fireproof glazing panel comprises at least one layer of swelling material associated with at least one structural layer of the panel. The swelling material layer is formed by combining the grains of the swellable hydrated metal salt and has a total water content of from 20 to 26% by weight. In the panel manufacturing process, the swellable hydrated salt grains have a total water content of from 22 to 26% by weight. divided into a layer on the surface of the layer to be built into the panel, and while the grains are clamped between the pair of molding plates, the layer is degassed, solidified and attached to the surface of the panel layer under appropriate temperature and pressure conditions.

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The invention relates to a transparent fireproof glazing comprising at least one layer of swelling material associated with at least one structural layer of a panel. The invention further relates to a method for producing a transparent fireproof glazing panel as defined above.

BACKGROUND OF THE INVENTION

It is known to bond layers of swelling material to sheets of glazing material to form fireproof panels. For example, such a layer of swelling material may be sandwiched between two glass sheets. Very important applications of such panels are transparent shades that allow illumination of the shaded area, and closures' through openings for rooms or other closures where there may be a danger of fire.

Typically, the performance of such panels is tested by incorporating them into the furnace wall, the internal temperature of which then increases according to a predetermined pattern, details of which are given in International Standard ISO 834-1975. The fire resistance test method described in this standard is also given in ISO 9051-1990, which deals specifically with the fire resistance properties of glazed assemblies. It is appropriate to list here some parts of this standard.

Glass is a non-combustible material and therefore does not contribute to the spread of fire.

Glass exposed to heat may crack by thermal shock or shrink and then not be held by the frame. Thus, only some types of glazed assemblies can be considered fire resistant. The ability of glazed assemblies to resist fire depends on the type of glazed article, the glazing method, the frame type, the panel size / mounting method and the type of construction surrounding the glazed area.

Some transparent and translucent glazing assemblies may meet the requirements of stability and integrity (RE) and in some cases of insulation (REI, where R stands for resistance, E for tightness and I for insulation).

Not only is the possibility of direct fire propagation through openings caused by glass fracture to be taken into account for action against fire: it is also to take into account the number of heat-permeable glazing assemblies which can remain intact, and such heat can cause ignition of flammable materials

2Glass assemblies with fire resistance of class RE under the fire conditions defined in ISO 834 ensure stability and integrity at a given time. The temperature of the unexposed side is not taken into account.

Glazed assemblies with fire resistance according to the REI class under fire conditions defined in ISO 834 ensure stability, integrity and insulation at a given time.

There are various grades of fireproof panel, and among those generally considered are those corresponding to panel Cm, which constitute effective barriers to flame and smoke, i.e., class RE, for time periods of 15,30,45,60,90 and 120 minutes. Other stages correspond to panels that create effective barriers to the passage of flame and smoke and also have certain insulating properties, that is, the REI class, again for periods of time such as 15,30,45,60,90 and 120 minutes »

The insulating properties that a panel must have to meet the REI standard are, in short, such that no point of the top that is extended at the furnace higher than 180 ° C above its initial or ambient temperature. , and the increase in the mean temperature of this surface must not exceed 140 ° C. Such panels belonging to the REI class may also form obstacles to the transmission of infrared radiation from the fire bearing.

It is of utmost importance that the swelling material layer of such a panel has good flame retardant properties and also retains acceptable optical properties than the initial flame retardant.

For many years, hydrated metal salts, such as metal silicates, especially alkali metal silicates, have been used to produce such panels. Typically, the layers incorporated in the finished panels had a water content of 29% to 35% · When describing the water content in this description, it is the proportion by weight of water relative to the swelling material used to form the layer or proportion by weight relative to the swelling material As a layer in the finished panel before the fire breaks out and then remakes the layer. In the course of fire, the water of hydration is expelled by the fire, and the layer of swelling material turns into an opaque foam which acts as an obstacle to radiated and conduction heat and can also serve to join structural layers of the panel such as glass layers shock caused by fire. Thus, the effectiveness of the panel as a barrier to flame and smoke penetration is prolonged.

The effectiveness of the hitherto known type of panel as a fire shield depends on several factors. The efficiency of a laminate consisting of a single layer of a given swelling material sandwiched between two glass sheets of a given thickness increases with the thickness of the swelling material. For a previously known panel of a given basis weight, i.e. for the same overall thickness of glass and the swelling material, the efficiency of such a known panel can be enhanced by forming it as a five-layer laminate comprising two layers of swelling material sandwiched between three glass sheets. A laminate of three 4 mm glass sheets enclosing two layers of 1 mm swelling material proved more effective than a laminate of two 6 mm glass sheets enclosing one layer of 2 mm swelling material. Thus, the same efficiency can be achieved by using a thinner panel having multiple layers. It is clearly desirable to provide highly efficient fire-resistant panels having a low basis weight, but the manufacture of panels with four or more layers can be very costly.

Another problem associated with the use of hydrated metal salt layers as layers of swelling material is the aging of the material with time. The aging manifests itself as a violation ee optical properties of the panel, such as transparency sníženf hydrated intumescent material which reduces the transparency in the panel, such an infringement ₀ characteristics of the panel is a clear defect for its use.

For many years, the problem of breaking optical properties by the aging of a fire-resistant panel containing a layer of swelling material has been known. Various efforts have been made to address this problem. The most important cause of the optical properties was the formation of microbubbles in or on the layer and it is known to form a layer by drying in situ an aqueous solution of a hydrated metal salt which has been degassed, taking care not to stir the solution too vividly dissolution of air or other gas that may occur when the dried layer ages. Although this measure gives an improvement in the aging properties of the panel, it is not entirely satisfactory if the panel is to be used; under conditions where it is exposed to heat, such as direct heat

-4 sunlight. It is also known to add some stabilizing agent to a hydrated metal salt, such as a partially dissociated organic nitrogen compound, for example a quaternary ammonium compound such as tetramethylammonium hydroxide, which gives better results.

It is an object of the present invention to provide a transparent flame retardant glazing panel that has good aging properties that are not critical of the use of such an additive, and which also has good flame retardant properties during fire.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION The present invention provides a transparent fireproof glazing panel comprising at least one layer of swelling material associated with at least one structural panel of the panel comprising a structural layer which is joined to a layer of swelling material that has been formed by bonding and a total water content of from 20 to 26% by weight.

It has been found that such a panel is less susceptible to deterioration of its optical properties over time than a known panel in which the water content is somewhat higher. Indeed, the aging properties of the panel according to the present invention have the same other parameters as those of a panel whose swelling material has a higher water content in the range of 29% to 34% by weight and which contains a stabilizing agent such as tetramethylammonium hydroxide. This is rather surprising and it is not entirely clear why this favorable result is achieved by using a swelling layer having a lower water content.

Further, it is surprising that such a panel may have improved fire resistance properties, as it would rather be expected that a lower water content in the swelling layer would reduce the panel's performance,

Because the foaming action during the fire will be reduced. In fact, it has been found that a three-layer laminate comprising one layer of swelling material sandwiched between two glass beads according to the present invention has better fire resistance than a three-layer laminate of similar size whose swelling layer has a higher water content. Accordingly, the invention has the additional advantage of allowing the same degree of fire resistance to be achieved by using a thinner and lighter panel without the added complications and cost of increasing the number of laminate layers.

Lower water content in the swelling layer.

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-5the increase in its hardness, so it is physically more stable and has less tendency to split. It is advantageous to produce a layer with a water content of not less than 20% for the manufacture of panels having good transparency.

Preferably, the layer has a water content of not less than 22%. The presence of lacquer proportions of water in the swellable layer very well promotes foaming properties during fire and also allows the formation of a hard and compact layer of swelling material that maintains good optical properties over time. Optimally, the layer has a total water content of not less than 23%.

For best results, it is preferred that the layer have a total water content of not more than 25%, as this promotes maintaining good optical properties independently of panel aging.

The lacquer layer of the grains can be easily solidified by subjecting it to suitable thermal and pressure conditions to form a layer in which the individual grains are not visible to the naked eye, so that the layer has a uniform appearance and is transparent. However, the presence of such grains may be revealed, for example, by ultrasound testing or microscope observation, and the grain boundaries, although invisible, are believed to remain in the layer. It is contemplated that this layer structure may have some influence on the behavior of the swelling material during fire as well as on the properties of the fire layer. One possible contributing factor for improving the fire resistance of a panel according to the present invention is that although grain boundaries disappear to the naked eye it acted as a plurality of bubble formation sites in the reaction of the swelling material during fire, resulting in a fine foaming structure which has a good and uniform insulating effect over the entire panel area.

The grains preferably have a maximum dimension of less than 70 µm and are preferably greater than 10 µm and, for example, have a maximum dimension of between 150 µm and 500 µm. This facilitates the easy shaping of the grains into a compact layer and may also have a beneficial effect on the behavior of the swelling material of the fire. It has been found that the panels having this measure according to the invention give a fine and uniform foam structure when subjected to the intense heat generated by the fire. It is believed that this is mainly due to the relatively low water content of the swellable material compared to the water content used to date in the manufacture of fire-resistant panels, as well as the fact that some residual granularity remains in the hardened layer, favorable factor.

As noted, the effectiveness of the fireproof panel during fire depends at least in part on the thickness of the layer or each layer of the swelling material. Preferably, the swelling material layer has a thickness of from 0.1 to 50 mm. Layers of 0.1 mm thickness can provide adequate short-term fire protection, although naturally better protection is due to thicker layers. Generally, the thickness of such a layer zvčtšení over 5 them does not adequately increase protection and was also found to be obtížnšjší create thicker compact layers having good optical properties ₀

The swelling material may be selected from a large number of hydrated metal salts, although the use of alkali metal soil is preferred. Examples of suitable alkali metal salts which can be used in hydrated forms are these; potassium aluminate, potassium lead, tin (II) tin, sodium tin (II) tin, sodium aluminum sulfate, potassium aluminum sulfate, sodium borate, potassium borate, sodium orthophosphates and potassium silicate. For reasons of cost and efficiency, however, it is preferred that the swellable material is hydrated sodium silicate, which may optionally be mixed with hydrated potassium silicate.

The panel comprises preferably two structural layers which are laminated with a layer of swelling material. This is a very stable and simple panel structure. In the simplest form, such a laminate may consist of two sheets of glazing material which are directly connected to each side of the swelling material layer. Alternatively, if a higher degree of fire protection is desired, two layers of swelling material may be joined to form a laminated panel with three structural layers of glazing material. It will be appreciated that when more fire protection is desired, two or more such panels may be laminated, for example by using an embedded adhesive material such as polyvinyl butyrate in a manner known per se in the field of glazing laminates.

It has been stated that the aging properties of a panel according to the present invention are, for the same other parameters, better than those of a panel whose swelling layer has a higher water content in the range of 29% to 34% and contains a stabilizing agent. It was therefore natural to believe that there is no reason to use such a stabilizing agent in a panel whose swelling material layer has a low science content according to the present invention since such a panel already has a very good

-7 aging properties. However, the use of tat stabilizers may result in a further improvement in the aging properties of the panel of the present invention and may have some and very unexpected advantage in that the use of the crayfish reagent promotes fire retardancy during fire, and this is particularly beneficial for a panel having multiple layers of swelling material. additive. Thus, it is preferred that such a layer of swelling material comprises at least one silicate stabilizing agent.

The silicate stabilizing agent preferably comprises at least one organic nitrogen compound, for example an amine compound that is at least partially dissociated, for example a quaternary ammonium compound such as tetramethylammonium hydroxide. It is contemplated that the addition of a stabilizing agent such as tetramethylammonium hydroxide in accordance with a preferred embodiment of the present invention not only provides additional benefit in terms of panel aging, but may also have a beneficial effect on the lattice formed during fire and thus contribute to the panel fire resistance.

The panel according to the present invention can be manufactured very simply. SUMMARY OF THE INVENTION The present invention provides a process for the manufacture of a transparent fireproof glazing panel comprising at least one layer of intumescent bonded material and at least one structural layer of a panel, wherein the grains of the swellable hydrated metal salt have a water content of 22% to 26% by weight. of the layer to be built into the panel, and while the grains are deposited between the pair of shaping plates, the layer is subjected to thermal and pressure conditions for degassing and solidification and bonding to the altered surface of the panel layer.

Such a method is very simple to carry out and can be carried out using devices known per se in the field of glazing laminates.

In addition to providing very good aging properties and fire resistance of the panel, the choice of swelling grains having said water content causes other advantages. The use of swellable grains having a water content of not more than 26% promotes the retention of the optical properties of the panel regardless of its aging and such grains are also suitable for handling before and during the manufacture of the panel. Swelling grains having a water content of not less than 22% are readily solidified into hard and transparent layers, or at least into layers that become

8 'transparent when engaging between two transparent panes. This does not mean that the resulting swelling layer will need to have a water content of 22% · or higher. Some water is likely to be removed during degassing, but the mean water content of the layer will be only slightly lower than the mean water content of the grains from which the layer was formed. It has been found that the difference in water content in the grains and in the layer is at most 2% can be neglected, so that for example a layer made of grains with a medium water content of 25% will have a mean water content between 23% and 25%. When grains with a lower water content are used for the production of the layer, it is desirable to control the conditions of the degassing so that only a small amount of water is removed: it is not desirable to have an average water content in the oyl of less than 20%. water is not less than 22% _O

During degassing and solidification, the swelling layer is attached to the panel layer with which it is in contact. This layer may be a film of thermoplastic adhesive material for subsequent bonding to a structural laminate panel such as glass panes, and although this is particularly desirable for some particular reason, it introduces a particular step in the manufacturing process and therefore it is preferable to distribute the grains into the a surface of the glass sheet which will form part of the panel and which also forms the forming plate.

If it is desired that the second shaping plate is not bonded to the resulting swelling material layer, it may be suitably treated, for example with silicone, but it is preferred that the second shaping plate is a layer or adjacent to a layer that will be incorporated into the panel and to which the layer of swelling material will be attached. Thus, a layer of swelling material may be sandwiched between two layers of a panel that is laminated together with the degassing and hardening. The panel can then be conveyed to the autoclave for the next high pressure bonding step, if desired.

It should be noted that any desired number of successively alternating layers of glazing and swelling material may be laminated in such a manner, but the difficulty of producing a laminate having good optical properties increases with the number of layers of swelling material, particularly when three or more such layers are to be strengthened simultaneously. the grouping shall be subjected to heating during operation. strengthening and / or bonding such layers as described below.

It will also be noted that two or more such panels consisting of alternating layers of glazing material and swelling material may be laminated using a film of adhesive thermoplastic material when greater fire resistance is desired. The coating process has practical advantages where it is desirable to incorporate a plurality of layers of swelling material.

As a practical example, it could be desirable to produce a fireproof panel having four layers of swelling material, each 1.5 mm thick. It has been found that the grain layers of the swelling material to form such reinforced layers must be up to seven times thicker than the solid layers so that such a panel can shrink in thickness! during degassing and joining up to 36 mm. Manufacturing is simplified by making two panels each having two layers of swelling material and laminating these panels using a film of a sticky thermoplastic material such as polyvinyl butyral. The presence of such a film of sticky thermoplastic material can also have a beneficial effect on the fire resistance properties of the panel by limiting the thermal shock transmission.

In the most preferred embodiments of the invention, said grains have a total water content of not less than 23% and preferably not more than 25% by weight. The presence of such proportion of water in the intumescent grains creates mechanical good foaming properties of the resulting layer during OHNS and also allows the creation of a hard and compact layer of intumescent material which has a zachovévá have good optical properties over time ₀

Preferably, the grains are sized so that at least 90% by weight of the grains have a maximum dimension of less than 700 µm, preferably in the range of 150 µm to 500 µm. Two sizes of these sizes are provided. They are suitable for handling and give the resulting rigid layered structure which is considered to be beneficial for good fire-resistance properties as mentioned above. Such grain sizes are also particularly advantageous for forming layers of the most desired thicknesses, for example from 0.1 to 5.0 mm _e.

Preferably, for at least part of the degassing and bonding time, the swelling material layer is subjected to a temperature of at least fs0 ° C. Heating the swellable material to such a temperature aids in degassing and firming as well as bonding to the panel layer. It should be noted that the swelling material must not be subjected to such high temperatures that, due to the pressure exerted on the swelling material,

-10to cause premature expansion of the swelling material. It should be noted that it is much easier to ensure that a single layer of swelling material, or each of the two layers of panel swelling material, is subjected to a cptimal heating process rather than ensuring that each of the three or more layers is optimally heated, even if 2. The method according to claim 1, wherein the middle layer or layers are more shielded from the heat source by other panel layers than the outer layers _P

Advantageously, during degassing and bonding, the swelling material layer is subjected to a pressure of less than 30 kPa, thereby allowing complete degassing of the swelling material. »

In the foregoing, the use of primed sets in a layered swelling material was discussed to improve

The use of such an additive may have other unexpected advantages in improving the fire resistance of bshen; will bend as it was said. Thus, it is preferred that the swellable material comprises at least one silicate stabilizing agent, preferably a stabilizing agent comprising at least one organic nitrogen compound, for example an amino compound that is at least partially dissociated, for example a quaternary ammonium compound such as tetrymethylammonium hydroxide.

An overview of the giants in the drawings

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram of an apparatus for degassing and consolidating a layer of swelling material according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The FIG is a panel formed from two glass sheets 1,2 and the intermediate layer 2 ^of grains of intumescent material having a total water content of between 22% and .26%, the grains are in the range of vellkost ^ I 50 to 500 / um. Grains are. simply scattered on the first glass sheet in a layer seven times thicker than the resulting thickness of the stiffening layer to be ^! made. The panel is enclosed in the housing 4., The housing 4 is connected by a suction line? The pump 6, which can maintain a vacuum in the housing 4 and also in the gap between the glass panes 1 and 2. When the pump 6 operates, the upper and lower walls of the housing 4 are attracted to the outer surfaces of the housing enclosed in the housing 4 and the glass panes. 1,2 acts as shaping plates for the swelling layers 3 of the intumescent material. The sleeve 4 is tapered at its peripheral region 2.

Sufficiently rigid to resist clamping against the edges of the stack of layers 1, 2, 2 such that a vacuum is maintained in the cavity (8) by the pump (6) around their edges in the housing (6).

The use of a housing 4 that surrounds the stack of layers 1, 2, 2 has the advantage that the size of the housing 4 is not critical with respect to the dimensions of the stack of layers 1, 2, 2. The sleeve 4 can be used for stack assemblies 1,2, 2. different sizes. The use of such a sleeve 4 also facilitates the application of the same pressure over the entire surface of the main faces of the stack of layers 1, 2, 2 during their processing so that reaction forces arising from pressure differences between the environment in which the sleeve 4 is located and to bend the board 1,2 grouping. Such a bend could lead to the formation of bubbles at the edges of the swelling material layer 2 and could also cause an uneven end product.

In a variant of the described apparatus, there are provided support means for absorbing the reaction forces arising from the pressure differences between the inside and the outside of the housing. In FIG such embodiments support means is a pair of the frame 2 of the same shape but vštších dimension than the set of layers 1,2,2 ^much kept apart bolts 10 to hold the housing £ out of contact with the edge of the assembly

1, 2, 2 layers after the swelling of the swelling material layer 2 to its final thickness as shown in the drawing.

Non-illustrative heaters for heating the swellable material layer 2 sandwiched between the glass panes 1,2 may be provided at both the top and bottom surfaces of the casing to facilitate consolidation and bonding of the stack of layers 1,2,2 ·

The layer assembly 1, 2, shown in FIG. 1, may be treated by a pumping device in a simple process in which the outside of the housing is always exposed to air pressure. In one example of the method, the pump 6 is turned on to reduce the pressure in the housing, i.e. the pressure applied to the edges of the layer assembly 1,2-3. of the peripheral cavity 8, to a value below 10 kPa. The exact optimum value will depend on the water content of. used swelling grains. Setpoint can be obtained: after a few minutes, and maintained for 100 daléích r.inut, Sesteýa layers 1,2,2 ^{χ ,,} - and not the start of room temperature, 20 ° C, and then within the housing £ heated renders the product unacceptable after 45 minutes reaches. 90 ° C.

After the required degassing, the pressure inside the housing is brought back to atmospheric pressure for 15 minutes. At the end of this time sc finds that the swelling material layer 2 is solidified such that

-12The interfaces between grains are not visible to the naked eye and the layer assembly 1,2,2. I ^t is connected to the transparent laminated panel. Optionally, the panel may be transferred to an autoclave for high pressure treatment, if desired

The water loss in the swelling material was found to be less than 2% by weight of the layer due to the suction during consolidation into the layer »

Example 1

As described above, a series of panels were produced using 3 mm glass sheets with a 1.5 mm thick layer of swelling material and a total water content of 23.5% to 24.5%. The swelling material layer of each such panel was formed from grains having a total water content of 24-5% and sieved so that their size was from 150 µm to 500 µm. The weight ratio of silica to. The sodium oxide in sodium silicate was between 3.3: 1 and 3.4: 1. The grains of the swelling material contained no tetramethylammonium hydroxide in any fire-promoting additive.

A series of comparative panels of similar dimensions were produced in a conventional manner, in which to form such a panel, the hydrated sodium silicate solution was dried in situ on a 3 mm thick glass sheet to form a 1.8 mm thick layer over a thickness range of 1.5 mm up to 2,1 mm and with a total water content of 29% to 34%. The solution contained 0.25% by weight. The weight ratio of silica to sodium oxide in sodium silicate was again between 3.3: 1 and 3.4: 1. A second 3 mm thick glass sheet was attached to this layer to form a laminated panel

The panels were framed in essentially the same frames to create glazing assemblies for testing according to the international standard ISO 834-1975.

Two glazing assemblies, each of one row of panels, the tulles then built into the furnace roof, and the furnace was heated according to a predetermined scheme to test the stability and integrity of both assemblies as barriers to flame and smoke according to RE class. that the benchmark kit has satisfied ISO 834 at the RE level for 30 minutes but not for 45 minutes. The assembly comprising a panel according to the present invention satisfied the ISO 834 standard at an RE level above 60 min.

Both types of panels have also been tested for aging. In the first test, the panels were maintained at 80 ° C for 15 days. At the end of this time, no microbubbles were visible in the panel according to the present invention, while a number of bubbles were visible in the comparative test panel so as to form fogging despite the presence of a stabilizing agent in its swelling layer material. In the panel of the present invention, fogging only occurred after 30 days _. In the second test, the panels were exposed to ultraviolet radiation for 500 hours. The panel of the present invention did not contain any microbubbles after this time, but the comparative test panel contained more than twice the amount of bubbles than after the first test _of

Example 2

Two other rows of panels according to the invention were made using the same starting materials as in Example 1. In these rows, the panels consisted of three glass sheets of 3 mm thickness and two layers of swelling material of 1.5 mm thickness. In one of the panels of the invention, the swelling material layers contained a proportion of tetramethylainone hydroxide; second, there was no such additive. Tetramethylammonium hydroxide was added by addition to the silicate solution from which the grains formed were present in a proportion of 0.125% by weight. CS comparative test panels asks structure, being made using a solution of hydrated sodium silicate with the addition of tetramethylammonium hydroxide share of the specification of the comparative test panels of Example l _of layers of intumescent material such comparative test panels mëly average thickness 1.8 mm.

The panels were again framed in identical frames to create glazing assemblies for testing according to the international standard ISO 834-1975.

Such glazing assemblies were then routinely incorporated into the furnace roof and the furnace was heated according to the required predetermined scheme for testing the stability, integrity and insulation of both REI class classes. Various assemblies have been found to have the ability to maintain integrity as a barrier to flame and smoke penetration as well as meet insulation requirements in a REI class for between 30 and 35 minutes.

Other members of each row of glazing sets were subjected to the aging tests set forth in Example 1. It was found that by each test all panels of the invention gave better results than comparative test panels, and also those panels of the invention in which the swelling material contained tetramethylammonium hydroxide, gave better results than panels without anything.

Example 3

Two further rows of panels according to the invention were prepared as described in Example 2 except that one of the outer glass panes of the panel had a thickness of 2 mm, less than 3 mm. The panels of each row were slaminated with a glass pan of 2 bowls inside using 0.76 mm thick polyvinyl butyral films.

In one row of these polyvinyl butyral laminated panels each contained four layers of 1.5 mm thickness of hydrated sodium silicate with tetramethylammonium hydroxide, while in the second row it was not used. /

The panels were again framed in substantially harmless frames to create glazing assemblies for testing in accordance with the international standard ISO 834-1975.

The assembly was then built into the furnace wall and the furnace was heated according to a predetermined scheme to test the efficacy of both series, again according to the REti class. as an obstacle to the penetration of letters and skin and to satisfy the requirements of insulation class REI for 55 to 70 minutes. Seets according to the invention, the panels of which contained tetramethylammonium hydroxide, remained effective as barriers to flame and smoke penetration and satisfy the insulation requirements of the RIIPb class for 70 to 80 minutes.

Example 4 'I'. · '' Zf ^! . ? - '

Additional rows / glazing assemblies were made by laminating and scraping three panels of the invention made in the method of Example 2 using 0.76 mm thick polyvinyl butyral layers. The white flood assemblies are routed to the roof of the furnace and the furnace was heated according to the desired predetermined performance test scheme, again according to the REI class. It has been found that the inventive assemblies have remained effective as barriers to flame penetration. and kouýe and satisfied the demands of isolation

The REI class for more than 90 minutes, and when tetrsmethylammonium hydroxide was used as an additive to improve fire resistance, met the REI class requirements for 110 minutes.

Example 5

Two refractory panels according to the invention were produced, each comprising three 3 mm glass panes and two layers of swellable material 0.6 mm thick. In one panel, the swelling material contained tetramethylammonium hydroxide as a flame retardant according to Example 2, in the other panel such additives were not used.

Framed assemblies containing the two panels were then tested for stability, integrity and insulation under the REI class when exposed to fire. The panel without additive was broken after 34 minutes. The additive panel withstood the effects of the test for 35 to 36 minutes.

Example 6 "=,

Two fire-resistant panels were made, each containing three 3mm, 8mm and 3mm glass sheets and two layers of swelling material. In one panel, each layer of swelling material formed according to the invention was as described in Example 1 having a thickness of 25 mm. In the other panel, the layer of swelling material formed having a thickness of 1.8 mm was the classical technique described in 8 with the comparative test panel of Example 1.

Framed assemblies containing the two panels were then tested for stability, integrity and insulation under the REI class when exposed to fire. The comparison test panel was disrupted after 40 minutes. The panel according to the invention withstood the effects of the test for 50 minutes.

Claims (22)

CLAIMS 1. Transparent fire-resistant glazing panel comprising at least one layer of swelling material joined and at least one structural layer of a panel, characterized in that it comprises a structural layer which is joined to a layer of swelling material which has been formed by joining grains of swellable hydrated metal salt. water from 20 to 26%. 2. A transparent fire-resistant glazing panel according to claim 1, characterized in that it comprises two structural layers which are laminated together with said layer of intumescent material. 3. A transparent fire-resistant glazing panel according to claim 1 or 2, characterized in that the layer of swelling material has a total water content of not less than 22%. 4. A transparent fire-resistant glazing panel according to claim 3, characterized in that the layer of swelling material has a total water content of not less than 23%. 5. A transparent fire-resistant glazing panel according to any one of items 1 to 4, characterized in that the layer of swelling material has a total water content of not more than 25%. 6. A transparent fire-resistant glazing panel according to any one of items 1 to 5, characterized in that the grains have a maximum size of less than 700 µm and preferably have a size of from 150 µm to 500 µm. 7. A transparent fire-resistant glazing panel according to any one of items 1 to 6, characterized in that the layer of swelling material has a thickness of 0.1 mm to 5.0 mm. 8. A transparent fire-resistant glazing panel according to any one of claims 1 to 7, wherein the swellable material is hydrated sodium silicate. 9. A transparent fire-resistant glazing panel according to any one of claims 1 to 8, wherein the layer of swelling material comprises at least one silicate-stabilizing agent. 10. The transparent fire-resistant glazing panel of claim 9, wherein the silicate stabilizing agent comprises at least one organic nitrogen compound, for example an amino compound which is at least partially dissociated, for example a quaternary ammonium compound such as tetramethylammonium hydroxide. A method of making a transparent fireproof glazing panel comprising at least one layer of swelling material associated with at least one structural layer of the panel, wherein the grains of the swellable hydrated metal salt having a water content of 22% to 26% by weight are separated into a layer on the surface of the layer; to be built into the panel, and while the grains are sandwiched between a pair of molding plates, the layer is subjected to thermal and pressure conditions for degassing and bonding and bonding to a modest surface of the panelUo layer. 12. The method of claim 11, wherein the grain layer is distributed on the surface of the glass sheet to be incorporated into the panel and forming the molding plate. 13. The method of claim 12, wherein the second molding plate comprises a layer to be incorporated into the panel and to which a layer of swelling material is attached. 14. A method according to any one of claims 11 to 13, wherein the grains have a total water content of not less than 23% by weight. 15. A method according to any one of claims 11 to 14, wherein the grains have a total water content of not more than 25% by weight. 16. A method according to any one of items 11 to 15, wherein at least 90% by weight of the grains have a maximum dimension less than _Of 700 microns and is preferably from vellkost 17. A method according to any one of claims 11 to 16, wherein the layer of swelling material is formed in a thickness of 0.1 mm to 5.0 mm. 18. The method of any one of items 11 to 17, wherein the layer of swelling material comprises hydrated sodium silicate. 19. A method according to any one of items 11 to 18, wherein: v That at least part of the degassing and bonding time, the swelling material layer is subjected to a temperature of at least 80 ° C. 20. A method according to any one of claims 11 to 19, characterized in that during degassing and bonding the layer of swelling material is subjected to a pressure of less than 30 kPa. 21. The method of any one of items 11 to 20, wherein the swelling material comprises at least one silicate stabilizing agent. 22. The method of claim 21, wherein the agent is stable The licking silicate is at least one organic nitrogen compound, for example an amino compound which is at least partially dissociated, for example a quaternary ammonia compound, such as tetramethyl ammonium hydroxide. Represents í FIG.1 ______22 ^d