The present invention relates to processes for manufacturing panels of lamellar mineral wool, for use as sound, thermal and fireproof insulation of external walls of buildings, as well as ceilings of garages over which heated rooms are located.
Some methods for manufacturing panels of mineral wool are known. Technologies currently in use are based on the ascertainment that, most preferably, mineral wool fibres should be arranged perpendicularly to the surface of an insulated wall. Such an arrangement of fibres increases by many times the tensile strength when the tension is perpendicular to the panel surface, at a density lower than in other panels manufactured by traditional methods and with good (the best) thermal insulation, and at the same time it comprises the most ecological solution - lamellar panels may be fastened only with the use of gluing mortars, and they do not require the use of mechanical fasteners on carrying surfaces of the buildings which are up to 20 m high. Fibres arranged parallel to the wall plane tend to be tom off the panel surface under the influence of atmospheric conditions, and such panels must always be bonded to the walls both mechanically and with gluing mortars.
In the course of development of panel manufacturing systems various solutions have been proposed, aimed either at providing a better thermal insulation, or at obtaining more rigid panels.
Bonding rods together with the use of a bonding agent has not been employed in practice because the contact area of rods is much larger than the contact area of such a panel with a substrate it is to be laid on. In order to obtain a panel 20 cm wide it is necessary to bond a plurality of so-formed rods together. Our attempts to bond individual rods together with the use of the same bonding agent that was used for bonding fibres did not give the expected results.
In practice rods are bonded together with the use of strips, tapes, non-woven fabric or paper, on one side or on both sides of the panel (as in
Insulating characteristics of ready made panels additionally depend upon the way in which individual panels are bonded together at a construction site. The bigger the number of small panels necessary to form a requested surface, the bigger the number of edges at which panels are in mutual contact. The bigger the number of contact edges between the panels, the bigger the number of thermal bridges forming on the insulated surface as a result of inaccurate laying, improper adjustment of individual panels, and also as a result of increased risk of soiling contact surfaces with gluing mortars. At the same time the bigger the number of panels used to lay on an insulated surface, the longer the time required for laying the insulation on the building façade, and the costs of work is relatively higher than in case of larger panels.
On the other hand the size of produced panels is determined by the fact that the perpendicular arrangement of fibres in relation to the insulated surface is the most advantageous one, whereas on production lines a non-woven fabric is produced having its fibres arranged parallel to the panel surface. Therefore in order to manufacture a plate with fibres arranged perpendicularly to the insulated surface, it is necessary to cut off a strip from a web of non-woven fabric having a given thickness and to rotate said strip by 90° in order to change the fibre orientation. This in turn means that the thickness of so-obtained layer of non-woven fabric becomes, after the rotation, the maximum width of the panel.
Therefore the prior art has not sought a non-woven fabric of maximum thickness, but instead attention was focused on increasing the surface area of the obtained panel by cutting it lengthwise into thin rods, rotating these rods and subsequently bonding them together with the use of an additional connecting layer, e.g. made of paper. Besides in practice the size of the obtained panels did not exceed 20 cm x 120 cm, since lamellar panels of larger surface were insufficiently rigid and were not suitable for laying on flat vertical surfaces. A characteristic feature of so obtained panels is that lamellae constituting their elements have considerably smaller width than thickness.
In the process of the invention an attempt was made to reverse the approach to the techniques for manufacturing panels of mineral wool.
Thus in a first aspect of the invention we provide a method of bonding the surfaces of two elements formed of mineral fibre as defined in claim 1.
We find that the use of this particular type of adhesive, especially when it has the preferred features set out below, provides particularly durable connections for mineral wool elements, especially as the fibres are oriented predominantly parallel to the surfaces which are bonded, as in the production of lamellar insulation panels.
The hot melt adhesive is applied to the surfaces to be bonded by spraying and this spraying preferably lasts no more than 12 seconds.
After application of the adhesive the elements are subjected to pressure during bonding and preferably the total time for spraying and subjection to pressure is not more than 12 seconds.
In the process of the invention panels can be moved along stationary nozzles or stationary panels can be sprayed with the use of movable nozzles. Spraying time and adhesive bonding time is 12 seconds maximum. Panels sprayed with the adhesive are pressed together.
The adhesive can be applied to just one of the surfaces to be bonded but preferably it is applied to both.
It turned out that it was advantageous to prevent the penetration of the adhesive into deeper layers of the panel, and that such a connection would be more durable than a connection made by another method. Generally the adhesive does not penetrate more than 2 mm into the element.
Due to the short setting time of the adhesive, particular attention has to be paid to accurate positioning of strips relative to each other.
The hot melt adhesive is preferably applied at a temperature of from 150 to 185°C. Preferably the hot melt adhesive is a polyolefin-based adhesive. Its melting point is from 50 to 200 °C, preferably from 80 to 120°C, and especially about 100°C.
The panel may be made by gluing two or three strips (elements) together, which in case of maximum obtainable thickness of non-woven fabric layer makes it possible to obtain a panel of width of even 60 cm. In comparison with a conventional panel of width not exceeding 20 cm, it is possible to reduce by three times the time of laying insulation on a wall, as well as to reduce by three times the number of formed thermal bridges. The resulting width of so-obtained elements of the final product is always at least equal or greater than their thickness.
These benefits are achieved partly due to the choice of the adhesive used and the resulting strength of the bond between the elements. However, this benefit is also achieved by the method by which the elements are cut from the web and bonded together to form the insulation panel.
Thus according to a second aspect of the invention we provide a method of forming a mineral wool insulation panel comprising
providing a web of mineral wool having a top face and a bottom face and two opposing side faces and a first end defining the width of the web and a longitudinal direction parallel to the top and bottom faces and side faces and a transverse direction parallel to the top and bottom faces and perpendicular to the side faces, and a thickness between the top and bottom faces,
cutting at least two elements from the web, the cut being made in the transverse direction, so that the top and bottom faces of each element are formed from the top and bottom faces of the web,
bonding two elements together with the top face of one element being bonded to the bottom face of the other element to form a pre-panel,
and cutting from the pre-panel at least one insulation-panel comprising parts of at least two elements and having a predetermined thickness in which the thickness direction of the insulation panel is parallel to the bonded surfaces of the elements forming the pre-panel,
characterized in that the elements are bonded together using hot melt adhesive applied to one or both faces to be bonded by spraying.
In the second aspect of the invention the bonding between the elements is carried out preferably using the preferred aspects set out in connection with the second aspect of the invention.
In a third aspect of the invention, we provide a process for manufacturing panels of mineral wool as defined in claim 18.
In all aspects of the invention the final panel preferably does not include a cover layer but instead consists essentially of the mineral wool elements and the adhesive used to bond them together.
In all aspects of the invention, two or three (and in some cases more) elements can be bonded together to form the insulation panel. In this case they are bonded together at their largest surfaces. That is, the bottom surface of the first element is bonded to the top surface of the second element and the bottom surface of the second element is bonded to the top surface of the third element.
The insulation panels provided are useful for insulating various surfaces, including external walls of buildings and ceilings of garages over which heated rooms are located. They may be used as sound, thermal or fire insulation.
The insulation panel is applied to the surface to be insulated so that the bonded surfaces are perpendicular to the insulated surface. In the case where the web from which the elements are cut is formed so that the mineral fibres are predominantly parallel to the top and bottom surfaces of the web then this means that the fibres in the insulation panel are predominantly perpendicular to the surface to be insulated, as is preferred as indicated above.
The web from which the elements are cut can be formed in known manner. Generally it is produced by providing a mineral charge in a furnace, melting the mineral charge to form a mineral melt and forming the mineral melt into fibres. These fibres are collected as a web on a conveyer.
Fiberisation can be carried out for instance using rotors having a solid surface which are mounted about a substantially horizontal axis. The melt is applied to the surface of a rotor and flung from it to form fibres. Generally a series of rotors is used so that fibres are flung from a first rotor to a second rotor and from a second rotor to a third and optionally subsequent rotor(s). This system is known as a cascade spinner.
Alternatively, the fibres can be made using the well known spinning cup system in which fibres are thrown through apertures in a rotating cup and collected.
After collection on the conveyer the fibres can be treated, for instance by cross-lapping and/or compression. Generally they are formed into slabs which form the web from which elements can be cut in the invention.
Generally binder material is applied to the fibres before they are collected on the conveyer. This binder is usually heat-curable binder and the web of fibres is passed through a curing oven to cure the binder.
In all aspects of the invention the web from which elements are cut is preferably of unusually large thickness (ie the dimension between the top and bottom surfaces of the web). This thickness is preferably at least 100 mm, more preferably at least 150 mm and often at least 180 mm, in particular around 200 mm.
In all aspects of the invention the mineral wool material preferably has a density from 50 to 200 kg/m3, more preferably 75 to 130 kg/m3, in particular from 80 to 100 kg/m3, for instance around 90 kg/m3.
In all aspects of the invention cutting of the elements can be done in a conventional manner, for instance using saws.
From a web of non-woven fabric leaving the production line, said web being 20 cm thick and 2 m wide and having fibres oriented parallel to the plane of the non-woven fabric, strips 1.2 m wide were cut off crosswise. Said strips, 1.2 m long, 20 cm wide and 20 cm thick, were glued together by two at their largest surfaces. A thermofusible polyolefin-based adhesive was used, having fusing pointof about 100°C and working viscosity of 2700 mPa.s at 170°C. The adhesive was sprayed for 2.4 seconds with the use of stationary nozzles onto the opposite moving strips of non-woven fabric. Fifty spraying nozzles were used per each glued surface. The distance between nozzles and moving strips was 55 mm. Adhesive consumption amounted to 3.36 g of adhesive per one glue line 1.2 m long. The obtained panels were pressed together for 6 seconds. From the obtained panels strips 8 cm thick were cut off, said cutting being performed along the dimension of 1.2 m, and further sent for packing. The panel had the following dimensions: width - 40 cm, thickness - 8 cm, length - 1.2 m, and its fibres were arranged vertically to the insulated surface. A façade insulation made of the above mentioned panels was laid twice as quickly as in the case of traditional façade of single panels, and at the same time the panels bonded this way did not break at connection area, and could be lifted by one edge by a single worker, thus the obtained connection was durable. The amount of thermal bridges was reduced by half.
From a web of non-woven fabric leaving the production line, said web being 20 cm thick and 2 m wide and having fibres oriented parallel to the plane of the non-woven fabric, strips 1.2 m wide were cut off crosswise. The procedure was as in Example I, but three strips were glued together. A thermofusible polyolefin-based adhesive was used having fusing point of about 100°C and working viscosity of 2700 mPa.s at 170°C. The adhesive was sprayed for 2.4 seconds with the use of nozzles onto the opposite strips of non-woven fabric. Fifty spraying nozzles were used per each of the four glued surfaces. The distance between nozzles and strips was 55 mm. Adhesive consumption amounted to 2.36 g of adhesive per one glue line 1.2 m long. The obtained panels were pressed together for 8 seconds. From the obtained panels strips 8 cm wide were cut off, said cutting being performed along the dimension of 1.2 m, and further sent for packing. The panel had the following dimensions: width - 60 cm, thickness - 20 cm, length - 1.2 m, and its fibres were arranged vertically to the insulated surface. A façade made of the above mentioned panels was laid three times as quickly as in the case of traditional façade of single panels, and at the same time the panels bonded this way did not break at connection area, and could be lifted by one edge by a single worker, thus the obtained connection was durable.
From a web of non-woven fabric leaving the production line, said web being 20 cm thick, 1.2m wide and 2 m long and having fibres oriented parallel to the plane of the non-woven fabric, strips 1.2 m wide were cut off crosswise. Said strips, 1.2 m long, 20 cm wide and 8 cm thick, were glued together by two at their largest surfaces. A thermofusible polyolefin-based adhesive was used, having fusing point of about 100°C and working viscosity of 2700 mPa.s at 170°C. The adhesive was sprayed for 2.4 seconds with the use of stationary nozzles onto the opposite moving strips of non-woven fabric. Fifty spraying nozzles were used per each glued surface. The distance between nozzles and moving strips was 55 mm. Adhesive consumption amounted to 3.36 g of adhesive per one glue line 1.2 m long. The obtained panels were pressed together for 6 seconds. The obtained panels were sent for packing. The panel had the following dimensions: width - 40 cm, thickness - 8 cm, length-1.2 m, and its fibres were arranged vertically to the insulated surface. A façade insulation made of the above mentioned panels was laid twice as quickly as in the case of traditional façade of single panels, and at the same time the panels bonded this way did not break at connection area, and could be lifted by one edge by a single worker, thus the obtained connection was durable. The amount of thermal bridges was reduced by half.
From a web of non-woven fabric leaving the production line, said web being 20 cm thick, 1.2m wide and 2 m long and having fibres oriented parallel to the plane of the non-woven fabric, strips 1.2 m wide were cut off crosswise. The procedure was as in Example I, butthree strips were glued together. A thermofusible polyolefin-based adhesive was used having fusing point of about 100°C and working viscosity of 2700 mPa.s at 170°C. The adhesive was sprayed for 2.4 seconds with the use of nozzles onto the opposite strips of non-woven fabric. Fifty spraying nozzles were used per each of the four glued surfaces. The distance between nozzles and strips was 55 mm. Adhesive consumption amounted to 2.36 g of adhesive per one glue line 1.2 m long. The obtained panels were pressed together for 8 seconds. The obtained panels were further sent for packing. The panel had the following dimensions: width - 60 cm, thickness - 8 cm, length -1.2 m, and its fibres were arranged vertically to the insulated surface. A façade made of the above mentioned panels was laid three times as quickly as in the case of traditional façade of single panels, and at the same time the panels bonded this way did not break at connection area, and could be lifted by one edge by a single worker, thus the obtained connection was durable.
From a web of non-woven fabric leaving the production line, said web being 20 cm thick and 2 m wide and having fibres oriented lengthwise, strips 1.2 m wide were cut off crosswise. Said strips were rotated by 90° in horizontal plane. Then these strips were cut into strips 8 cm wide (this dimension is the final thickness of manufactured insulation) which were rotated by 90° around longitudinal axis thereof. The so-obtained strips, 1.2 m long, 20 cm wide and 8 cm thick, were glued together, by two. A thermofusible polyolefin-based adhesive was used, having fusion point of about 100°C and working viscosity of 2700 mPa.s at 170°C. The adhesive was sprayed for 2.4 seconds with the use of stationary nozzles onto the opposite moving strips of non-woven fabric. Two spraying nozzles were used, one spraying nozzle per each glued surface. The distance between nozzles and moving strips was 55 mm. Adhesive consumption amounted to 3.36 g of adhesive per one glue line 1.2 m long. The obtained panels were pressed together for 6 seconds. The obtained panels were sent further for packing. The panel had the following dimensions: width - 40 cm, thickness - 8 cm, length-1.2 m, and its fibres were arranged vertically to the insulated surface. The façade insulation made of the above mentioned panels was laid twice as quickly as in the case of traditional insulation of single panels, and at the same time the panels bonded this way did not break at the area of connection, and could be lifted by one edge by a single worker, thus the obtained connections were durable. The amount of thermal bridges was reduced by half.
From a web of non-woven fabric leaving the production line, said web being 20 cm thick and 2 m wide and having lengthwise oriented fibres, strips 1.2 m wide were cut off crosswise. Said strips were rotated by 90° in horizontal plane. Then these strips were cut into strips 20 cm wide (this dimension is a final thickness of manufactured insulation), and rotated by 90° around the longitudinal axis thereof. The so-obtained strips, 1.2 m long, 20 cm wide and 20 cm thick, were glued together by three. A thermofusible polyolefin-based adhesive was used, having fusing point of about 100°C and working viscosity of 2700 mPa.s at 170°C. The adhesive was sprayed for 2.4 seconds with the use of stationary nozzles onto the opposite moving strips of non-woven fabric. Twelve spraying nozzles were used, three spraying nozzles per each of four glued surfaces. The distance between nozzles and moving strips was 55 mm. Adhesive consumption amounted to 3.36 g adhesive per one glue line 1.2 m long. The obtained panels were pressed together for a period of 8 seconds. The obtained finished panels were sent further for packing. The panel had the following dimensions: width - 60 cm, thickness - 20 cm, length - 1.2 m, and its fibres were arranged vertically to the insulated surface. The façade insulation made of the above mentioned panels was laid three times as quickly as in the case of traditional insulation of single panels; and at the same time the panels bonded this way did not break at the area of connection, and could be lifted by one edge by a single worker, thus the obtained connections were durable.
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