Patent Publication Number: US-2013227910-A1

Title: Method for manufacturing and installing a textured tile flooring product

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from Canadian Patent Application No. 2,768,393 filed Feb. 22, 2012, the contents of which are incorporated by reference herein. 
     TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to tiles for use in flooring and related construction applications, and specifically to such tiles including cementitious materials. 
     It is known in the building construction and remodelling industries to employ tiles of varying base materials for flooring and other purposes. For example, the tiles can be composed of ceramic, cement, porcelain or stone, and are available in many varieties of colour, texture, size and strength. 
     Cement tiles have become a popular choice in the industry, due in part to the ability to easily introduce colour and texture into the material before it hardens into the final form, even mimicking more expensive stone products. Cement can also be provided with strengthening elements, such as fibre, before hardening. 
     It is known in the industry to employ cement tiles as flooring materials, particularly given their ability to be coloured or textured to suit a desired application or design. However, texturing a cement tile can be time-consuming or, where an automated process is involved, the pattern can be repetitious and hence less desirable. Also, as with any sort of flooring tile, cracking of grout between tiles allows the introduction of moisture and the resultant negative impact on sub-flooring. 
     What is needed, therefore, is a method for manufacturing a cement flooring tile with a textured surface that enables a non-repetitious pattern without requiring the expenditure of an undue amount of manufacturing time. Also, it would be advantageous to have a method for installing such a flooring tile in such a way that the risk of grout cracking is reduced. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention therefore seeks to provide a method of manufacturing and installing a textured cementitious tile flooring product, wherein sodium bicarbonate is used to texture the tile surface and a polyurethane caulking material provides flexible joints between tiles. 
     According to a first aspect of the present invention, there is provided a method of manufacturing a textured cementitious flooring product, comprising the steps of:
         (a) preparing a mold in substantially the shape of the flooring product;   (b) preparing a cementitious material;   (c) introducing a sodium bicarbonate layer onto an inner surface of the mold;   (d) introducing the cementitious material into the mold on top of the sodium bicarbonate layer to form a reaction interface between the sodium bicarbonate layer and the cementitious material;   (e) agitating the cementitious material to generate a randomly distributed reaction at the reaction interface;   (f) allowing the cementitious material to harden into the flooring product; and   (g) removing the flooring product from the mold.       

     In exemplary embodiments of the first aspect of the present invention, the inner surface of the mold can be optionally covered with a releasing agent before introduction of the sodium bicarbonate layer. The method may also optionally include the addition of a colouring agent into the mold on top of the sodium bicarbonate layer but before introduction of the cementitious material. Also, the method may include the further step of mixing a strengthening agent into the cementitious material before the cementitious material is introduced into the mold. 
     According to a second aspect of the present invention, there is provided a flooring product manufactured using the method of the first aspect. 
     According to a third aspect of the present invention, there is provided a method of installing a deck flooring product, comprising the steps of:
         (a) providing the flooring product;   (b) providing a substrate;   (c) applying adhesive to the substrate;   (d) installing the flooring product on top of the adhesive; and   (e) applying a polyurethane joint sealant between adjacent portions of the flooring product.       

     In exemplary embodiments of the third aspect of the present invention, a waterproof membrane can be provided on top of the adhesive, followed by the application of polyurethane strips positioned in a direction of desired water drainage. Flashing can also be installed over the outer edge of the membrane. 
     According to a fourth aspect of the present invention, there is provided a method of installing a flooring product over radiant heat tubing, comprising the steps of:
         (a) providing the flooring product;   (b) providing a substrate;   (c) installing a reflective sheet on top of the substrate;   (d) installing spacers on top of the reflective sheet;   (e) installing radiant heat tubing on top of the reflective sheet and adjacent the spacers;   (f) applying adhesive to upper surfaces of the spacers;   (g) installing the flooring product on top of the adhesive; and   (h) applying a polyurethane joint sealant between adjacent portions of the flooring product.       

     A detailed description of an exemplary embodiment of the present invention is given in the following. It is to be understood, however, that the invention is not to be construed as being limited to this embodiment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the accompanying drawings, which illustrate an exemplary embodiment of the present invention: 
         FIG. 1  is a flowchart illustrating an exemplary method of manufacturing flooring product according to the present invention; 
         FIG. 2  is a flowchart illustrating an exemplary method of installing a deck flooring product according to the present invention; 
         FIG. 3  is a flowchart illustrating an exemplary method of installing a radiant heat flooring product according to the present invention; 
         FIG. 4  is a cut-away perspective view of an installation according to the method illustrated in  FIG. 2 ; 
         FIG. 5  is a cut-away perspective view of an installation according to the method illustrated in  FIG. 3 ; 
         FIG. 6  is a drawing of two tiles caulked together in a flat orientation; and 
         FIG. 7  is a drawing of two tiles caulked together in a bent orientation. 
     
    
    
     An exemplary embodiment of the present invention will now be described with reference to the accompanying drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     As is indicated above, the present invention is directed to providing a method of manufacturing and installing a textured cementitious tile flooring product. Sodium bicarbonate is used to texture the tile surface through reaction with certain reactive components in the cementitious material, and a polyurethane caulking material is employed during installation in order to provide flexible joints between tiles. 
     Turning to  FIG. 1 , a method  10  of manufacturing a flooring product or tile is disclosed. In the method  10 , a mold is prepared in substantially the shape of the desired flooring product at  14  in a manner well known in the industry. The mold can be composed of steel, rubber, plastic, PVC or any other suitable material known to those skilled in the art as having the desired utility. Once the mold has been prepared, its inner surfaces can be optionally coated with a releasing agent such as oil or a similar lubricating agent at  16 ; not every mold composition will require such a coating, and again those skilled in the art would have knowledge suitable to making this determination. Whether a releasing agent is employed or not, the next step in the method  10  is the introduction of a layer of sodium bicarbonate onto the inner surfaces of the mold at  18 . Sodium bicarbonate will enable a reaction that generates a desired surface texture on the tile, as will be discussed below. The method  10  may also optionally include the addition of a dye or colouring agent into the mold on top of the sodium bicarbonate layer at  20  but before introduction of the cementitious material; in the alternative, colouring can be added directly into the cementitious material when the latter is being prepared. 
     At this point, or concurrently with one or more of the above mentioned steps, a cementitious material is prepared at  12  and introduced into the mold at  22 . The method  10  may include the further step of mixing one or more strengthening agents such as fibrous materials into the cementitious material before the cementitious material is introduced into the mold at  22 . It is know in the art that porcelain, ceramic and stone tiles are vulnerable to cracking because of a lack of internal reinforcing elements. Tiles according to the present invention are instead composed of cement and can therefore incorporate strengthening agents to help maintain structural integrity under concentrated impact or blows, with the result that one has a flooring product with the advantage of added strength and a desirable appearance such as stone. 
     The cementitious material is introduced into the mold interior and directly on top of the sodium bicarbonate layer. This forms a reaction interface between the sodium bicarbonate layer and the cementitious material; if a colouring agent has been introduced, this should not impact the reaction. Cementitious materials according to the present invention incorporate one or more of a variety of reactive materials, which can be selected as to type and volume at the discretion of the manufacturer. While the largest component in the cementitious material is preferably but not necessarily Portland cement, materials that will react with sodium bicarbonate are also present in varying percentages, such as metakaolin, fly ash and silica fume, although other reactive components are known to those having skill in the relevant art. When the cementitious material is introduced on top of the sodium bicarbonate layer at  22 , the sodium bicarbonate comes into contact with these reactive components and a reaction occurs, thereby creating pockets, caverns and voids in the concrete—this is the manner in which the texturing of the tile surface will occur. The extent of the texturing is therefore due in part to the amount of sodium bicarbonate used and the amount of reactive components in the cementitious material. 
     While this straightforward surface reaction will result in some degree of texturing of the tile surface, it has been found that agitating the cementitious material once it has been poured into the mold but before it has hardened will result in a more randomly distributed reaction at the reaction interface and hence more desirable levels of texturing. It is believed that this is the result of the agitation of the cementitious material pushing and dislocating the sodium bicarbonate layer which therefore spatially randomizes the reaction taking place at the reaction interface. This agitation takes place at  24  of  FIG. 1 , and it can be introduced through manual or automated means, as would be obvious to one skilled in the art. 
     The reaction and resultant texturing having been enabled, the cementitious material is allowed to harden into the flooring product at  26 , and the flooring product is finally removed from the mold at  28  and is ready for installation. 
     A flooring product having the desired characteristics can therefore be produced according to the above method  10 , and such flooring product is intended to fall within the scope of the present invention. A flooring product manufactured according to the above method  10  can be used in indoor and outdoor applications, and unlike porcelain or ceramic tile, such a flooring product would be considered a “structural tile”, capable of being laid over a wooden floor or deck and withstand the anticipated stresses. 
     Also, it is known to use natural stone having surface holes in flooring applications, such as travertine. These holes are normally filled when used in indoor applications where a smooth floor is desired, which is achieved by trowelling cement paste into the voids and then diamond-polishing the stone until smooth. This same process can be employed with a flooring product according to the present invention, again providing a flooring product with the same desirable appearance as natural stone but with greater structural strength. 
     Turning now to  FIGS. 2-5 , embodiments of flooring product installation are illustrated. Turning specifically to  FIGS. 2 and 4 , a method is disclosed for installing flooring product to a deck wherein polyurethane caulking material is employed during installation in order to provide flexible joints between tiles. 
     The method  30  is set out in  FIG. 2 , and it begins with providing a plywood sheeting substrate at  32 , although other substrates are known in the art of deck manufacture and tile flooring installation. A thinset adhesive is applied to the substrate at  34 , followed by an overlying waterproof deck membrane at  36 ; others methods and techniques for waterproofing the substrate and supporting structure may also be employed. Flashing is then installed at  38  over the outer edge of the membrane, and polyurethane adhesive strips are laid down on top of the membrane and flashing at  40  in a direction of desired water drainage. Tiles are then installed at  42 , and polyurethane joint sealant is introduced between all adjacent tiles at  44 . 
     In deck flooring installations involving tile, it is industry standard to utilize flexible control joints at approximately 10′-0″ on centre, in both directions, to allow for some degree of flexibility in the tile flooring, with the rest of the floor tiles grouted using conventional masonry grout (which does not allow any significant movement between adjacent tiles without cracking). The joints in the exemplary embodiment of the present invention are all filled with a flexible polyurethane caulking, however, which is injected down into the crevice between adjacent tiles, ensuring adhesion to each tile edge which gives a mechanical bond to the depth of the joint. This allows for a flexible expansion joint between all adjacent tiles and eliminates the commonly encountered grout cracking. 
       FIG. 4  illustrates in a cut-away perspective view how the various layers are configured in a deck installation  62  in accordance with the method disclosed in  FIG. 2 . The plywood sheeting  66  is placed over and secured to a deck support structure  64 , thereby providing a substrate for flooring installation. On the upper surface of the sheeting  66  is placed, in order: a thinset adhesive  68 ; a waterproof deck membrane  70  secured in place by the thinset adhesive  68 ; flashing  72  at the edge of the deck and secured by means known in the art; polyurethane adhesive strips  74  for directing water in a desired direction; tiles  76  secured in place by the adhesive strips  74 ; and a flexible polyurethane joint sealant  78  disposed between the times  76 .  FIG. 4  also illustrates the deck installation  62  with a wall component, which would include cap flashing  82  and common building wrap  80 , over which is positioned and secured a wall basestone  84  (which is of the same composition as the tiles  76 ) with joint sealant  78  employed at the joint. 
     Turning now specifically to  FIGS. 3 and 5 , a method is disclosed for installing flooring product on top of a radiant heat tubing system, wherein polyurethane caulking material is employed during installation in order to provide flexible joints between tiles. The method  46  is set out in  FIG. 3 , and it begins with providing a plywood floor sheeting at  48 , although other substrates are known in the art of tile flooring installation. A perforated reflective aluminum foil sheet is applied to the sheeting at  50 , followed by an overlying set of 1″×4″ spruce sleepers or spacers at  52 . The ½″ diameter radiant heat tubing is then installed at  54  in a manner known in the art on top of the foil sheet and adjacent the spacers. Polyurethane adhesive is applied at  56  to the top surfaces of the spacers and the tiles are then installed on top of the adhesive at  58 , with polyurethane flexible joint sealant introduced between all adjacent tiles at  60 . 
       FIG. 5  illustrates in a cut-away perspective view how the various layers are configured in a flooring installation  86  in accordance with the method disclosed in  FIG. 3 . The foil sheet  90  is placed over and secured to the floor sheeting  88 , and the sleepers/spacers  92  are in turn secured on top of the foil sheet  90 . The radiant heat tubing  94  is positioned and secured on top of the foil sheet  90  and adjacent the sleepers/spacers  92 . A polyurethane adhesive  96  is applied to the upper surfaces of the sleepers/spacers  92 , and the tiles  98  are secured on top of that by the adhesive  96 . A polyurethane flexible joint sealant  100  is then employed to fill the joints between the tiles  98 . 
     Turning to  FIGS. 6 and 7 , the positioning and flexibility afforded by the polyurethane joint sealant is illustrated.  FIG. 6  shows two adjacent tiles  102 , each having a textured surface  104 . The tiles  102  are joined by joint sealant  106 , which is injected between the tiles  102  and adheres to the opposing edges  108 ,  110  of the tiles  102 .  FIG. 6  illustrates the tiles  102  in a flat orientation as would be the case upon installation.  FIG. 7  illustrates the tiles  102  in the event that they move out of a flat orientation into a bent orientation, as might happen as a result of floor buckling or shifting. As can be seen, the joint sealant  106  is flexible enough and grips the tile edges  108 ,  110  securely enough that a significant degree of flexibility is allowed without breakage of the seal. 
     The foregoing is considered as illustrative only of the principles of the invention. The scope of the claims should not be limited by the preferred embodiments set forth in the foregoing examples, but should be given the broadest interpretation consistent with the specification as a whole.