Patent Publication Number: US-2015082590-A1

Title: Method of Providing a Mat Containing Aerogel and Apparatus for Implementing Such Method

Description:
The present invention relates to a method for providing a mat containing aerogel. 
     The invention also relates to an apparatus for implementing such method. 
     Nowadays the use of prefabricated panels is widespread for improving the thermal insulation of outer walls, ceilings and floors, the thickness of which is selected depending on the insulation requirements, optionally adapted with affixing systems that also make them convenient in terms of quick application and practicality of use. 
     Such prefabricated insulating panels are generally composed of a plurality of layers, and among the most widespread materials for the insulating layer are high-density rock wool and polystyrene-based and polyurethane-based materials. 
     The insulating layer is typically thickest in the package of layers which form the panel, the more so if such insulating layer is constituted by rock wool; the thickness of the insulating layer is often penalizing by the cubic shape of the spaces in which it is applied in order to form an inner covering. 
     Although widespread and appreciated, such conventional prefabricated insulating panels do not fully meet the requirements of the market, for which the need is increasingly felt to further improve both performance and compactness. 
     To fulfil this need of the market, the Applicant who submitted the present application has devised an insulating panel for the construction industry, which is described and claimed in PCT/EP2013/052776, and is characterized in that it comprises a shell made of fiberglass, the inner space of which contains insulating material that is at least partially constituted by aerogel. 
     In particular, at least one mat of material impregnated with aerogel is introduced into such shell. 
     Such mat is obtainable by using slabs or panels containing aerogel, of a conventional type, which however cannot be used in a process for producing the aforementioned panels in which the fiberglass shell is provided by pultrusion, and in which the mat with aerogel is inserted into the shell at the same time as it is produced by pultrusion. 
     The aim of the present invention is to devise a method for providing a mat containing aerogel, which can be wound on a reel and used for the continuous production of insulating panels for the construction industry. 
     Within this aim, an object of the invention is to provide a method for the production of a mat that can be used not only for construction, but also in other sectors in which it is necessary to produce an optimal insulation with encumbrances reduced to the minimum. 
     Another object of the invention is to provide a method that can be implemented with conventional technologies. 
     This aim and these and other objects which will become more evident hereinafter are achieved by a method for providing a mat containing aerogel, comprising the steps of:
         immersing a ribbon of fabric or non-woven fabric, unwound from a reel, in a solution of water and ethanol containing aerogel in suspension,   drying said ribbon impregnated with aerogel solution,   winding said dried ribbon containing aerogel onto a reel.       

    
    
     
       Further characteristics and advantages of the invention will become more apparent from the description of a preferred, but not exclusive, embodiment of the method according to the invention, which is illustrated by way of non-limiting example in the accompanying drawing wherein: 
         FIG. 1  is a schematic side view of a method, and of a corresponding apparatus for implementing it, according to the invention. 
     
    
    
     With reference to the FIGURE, a method for providing a mat containing aerogel according to the invention comprises the following operations:
         immersing a ribbon  11  of fabric or non-woven fabric, unwound from a reel  12 , in a solution  13  containing aerogel in suspension,   drying the ribbon impregnated with aerogel solution  14 ,   winding the dried ribbon containing aerogel  15  onto a rewinding reel  16 .       

     The method can comprise a final step of rewinding onto a reel, in which the rewinding is accompanied by the covering of the dried ribbon  15  with a film  17  which acts as a separator or has other functionalities before winding onto the rewinding reel  16 . 
     Such separator film  17  separates the various windings of ribbon on the reel of the rewinding reel  16 . 
     The solution  13  containing aerogel in suspension comprises water and ethanol, or other similar and equivalent solvents, in order to facilitate its evaporation. 
     The ribbon  11  is, for example, made of pile fabric, but it is understood that it can also be made of another similar and equivalent material. 
     Alternatively the ribbon  11  is made of glass wool. 
     Between the step of immersion in the solution  13  and the step of drying, the method includes a step of wringing in order to recover the excess solution  13  absorbed by the ribbon  11 . 
     The drying occurs at a temperature of between 70° C. and 80° C. 
     The method according to the invention ensures that the ribbon of fabric or non-woven fabric  11  loaded with aerogel by means of the solution in which the aerogel is in suspension can be used as an element with high insulating capacity, for example in order to provide panels for the construction industry, and being wound on a reel, and thus capable of being unwound from a reel, it lends itself to being used in continuous methods of production of insulating panels. 
     An apparatus for implementing a method according to the invention as described above, is generally designated with the reference numeral  10 . 
     Such apparatus  10  comprises, in addition to the reel  12  for the ribbon  11 , a vat  18  for the solution  13 , with internal redirection rollers  19  that are adapted to form a path for the immersed ribbon  11  which is longer than the length of the vat  18 ; in this manner a vat can be provided which has a contained length  18  with respect to the length of the path that the ribbon  11  travels when it is immersed in the solution  13 . 
     The ribbon  11 , as shown in the FIGURE, first passes below the first redirection roller  19  and then above the adjacent second redirection roller, to then pass below the third redirection roller. 
     The wringing step is performed by a pair of wringing presser rollers  20  and  21 , of which a first roller  20  is actuated by a corresponding electric motor  22 . 
     The drying step occurs in a climate chamber  23 . 
     Such climate chamber  23  has inner walls  24 ,  25  and  26  which form, in cooperation with corresponding redirection rollers  27 ,  28 ,  29  and  30 , a sinusoidal path that extends predominantly downward from above and vice versa. 
     In this manner a climate chamber  23  is provided, the floor space occupation of which is greatly reduced, but which is capable of making the ribbon being dried  14  take a path that is conveniently long and such as to ensure its prearranged drying. 
     The climate chamber  23  comprises means for drying for the impregnated ribbon  14 . 
     Such means for drying can be constituted, for example, by radiating panels, for example with electric resistors, arranged on the walls of the climate chamber  23 . 
     Alternatively, inside the climate chamber  23 , in place of the radiating panels using electric resistors, there can be high frequency heating means, or other systems of heating that are similar and equivalent. 
     The means for drying of the climate chamber  23  are associated with means for dehumidification, which should be understood as being of a known type. 
     The apparatus also comprises means for separation of the windings of ribbon with aerogel  15 , for a better use of the ribbon itself at the time of use. 
     Such means for separation are constituted for example by a reel of separator film  17 . 
     Optionally interposed between the reel  31  of separator film  17  and the rewinding reel  16  is a bonding agent dispenser  32 , if this should become necessary for covering the ribbon with aerogel  15  with the separator film  17 . 
     In the apparatus  10 , the shaft  40  of the rewinding reel  16  is the drive shaft, whereas the shaft  41  of the reel of the ribbon of initial fabric or non-woven fabric  14  is idle, as is the shaft  42  of the reel  31  of separator film  17 . 
     In practice it has been found that the invention fully achieves the intended aim and objects. 
     In particular, with the invention a method is devised for providing a mat containing aerogel, which can be wound on a reel and used for the continuous production of insulating panels for the construction industry. 
     Moreover, with the invention a method is devised for the production of a mat that can be used not only for construction, but also in other sectors in which it is necessary to provide an optimal insulation with encumbrances reduced to the minimum. 
     Last but not least, with the invention a method is devised, and a corresponding apparatus for implementing it, which can be implemented with conventional technologies. 
     The invention, thus conceived, is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements. 
     In practice the materials employed, provided they are compatible with the specific use, and the contingent dimensions and shapes, may be any according to requirements and to the state of the art. 
     The disclosures in Italian Patent Application No. PD2012A000065 from which this application claims priority are incorporated herein by reference. 
     Where technical features mentioned in any claim are followed by reference signs, such reference signs have been inserted for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.