Abstract:
A recyclable, thermoplastic backing material having the feel and weight of a rubber backing for use on a throw in mat. As compared with conventional rubber backed throw-in mats, the new thermoplastic material does not require a latex backing to adhere the rubber backing material to the primary backing layer. This may lead to decreased manufacturing costs associated with purchasing and applying the latex backing material. Further, because the material is recyclable, decreased costs associated with waste may be achieved.

Description:
BACKGROUND OF INVENTION  
       TECHNICAL FIELD  
         [0001]    The present invention relates generally to floor mats for vehicles and the like, and more particularly to a recyclable, rubber-like thermoplastic backing material used in a throw-in mat for a vehicle floor.  
         BACKGROUND  
         [0002]    Throw-in mats are often provided in vehicles for protecting carpeted vehicle floors. These mats typically include nibs formed on the back of the mat to grip the carpeted floor. The nibs extend from a backing layer that is secured to a primary backing layer and the carpet pile, and a carpet pile is tufted (sewn) into the primary backing layer.  
           [0003]    As shown in FIG. 1, a typical throw in mat  10  according to the prior art  10  includes a primary backing layer  12  having first and second sides  14 , 16  thereof. A carpet pile  18  is tufted, or sewn, into the first side  14  of the primary backing layer  12 . The primary backing layer  12  is preferably a woven polypropylene or non-woven polyester material.  
           [0004]    Coupled to the back side of the primary backing layer  12  is a latex backing layer  13  and a rubber backing material  15 . The latex backing layer  13  is necessary to adhere the tufted carpet pile  18  to the primary backing layer  12 .  
           [0005]    Alternatively, the primary backing layer  12  and the rubber backing material  15  (without the latex backing layer  13 ) could also be made of a thermoplastic material, which has a cost savings over rubber materials. However, typical thermoplastic backing materials that are used in throw-in mats lack the feel of rubber mats that is highly desirable among consumers. This is due primarily to the desire to produce throw-in mats that are light and inexpensive.  
           [0006]    Another problem with currently available throw-in mats is that the thermoplastic backing material is not recyclable. This leads to increase cost in manufacturing the throw-in mats associated with waste removal.  
           [0007]    It is therefore an object of the present invention to provide a thermoplastic backing material for use in throw-in mats that has the feel of rubber. Further, it is highly desirable if this thermoplastic material is also recyclable.  
         SUMMARY OF INVENTION  
         [0008]    In accordance with the above objects, a new thermoplastic backing for a throw in mat is proposed. The thermoplastic backing has the feel and weight of a rubber backing. Further, the backing is recyclable, thereby reducing costs associated with waste disposal.  
           [0009]    In addition, as compared with rubber backed throw-in mats, the new thermoplastic material does not require a latex backing to adhere the rubber-like backing material to the tufted carpet pile and primary backing layer. This may lead to decreased manufacturing costs associated with purchasing and applying the latex backing material.  
           [0010]    Other objects and advantages of the present invention will become apparent upon considering the following detailed description and appended claims, and upon reference to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0011]    [0011]FIG. 1 illustrates a section view of a throw-in mat according to the prior art;  
         [0012]    [0012]FIG. 2 illustrates a section view of a throw-in mat according to a preferred embodiment of the present invention;  
         [0013]    [0013]FIG. 3 illustrates a process for making the thermoplastic backing material used in FIG. 2; and  
         [0014]    [0014]FIGS. 4 and 5 illustrates the process for adding the thermoplastic material made in FIG. 2 to the primary backing material and carpet pile to form the throw-in mat of FIG. 2. 
     
    
     DETAILED DESCRIPTION  
       [0015]    Referring now to FIG. 2, a throw-in mat  10  is shown in accordance with the present invention. As shown, the throw-in mat  10  includes a primary backing layer  12  having first and second sides  14 , 16  thereof. A carpet pile  18  is tufted, or sewn, into the first side  14  of the primary hacking layer  12 . The primary backing layer  12  is preferably a woven polypropylene or non-woven polyester material.  
         [0016]    The carpet pile  18  may be of many constructions well known to those of skill in the art. Two carpet constructions commonly used include Shiva and Paramount.  
         [0017]    A recyclable thermoplastic backing material  20  is secured to the second side  16  of the primary backing layer  12 . The recyclable thermoplastic backing material  20  is preferably a recyclable thermoplastic material having the look and feel of a rubber backing. One preferred composition of the recyclable thermoplastic backing material  20  is shown below in Table 1. The recyclable thermoplastic backing material  20  is preferably extruded onto the primary backing layer  12 . This is shown below in FIG. 4. The recyclable thermoplastic backing material  20  is then heated under pressure to form a desired pattern on the bottom of the recyclable thermoplastic backing material  20 . This pattern can include a number of nibs  26  and grooves  22  to help secure the mat  10  to a carpeted vehicle floor.  
         [0018]    The composition of the backing material  20  is preferably based on an ethylene-octene copolymer formed using a metallocene catalyst and other processing aids. The ethylene-octene copolymer is then further processed to form the backing material  20  that is thermoplastic and recyclable. The backing material  20  provides a rubber feeling and weighted material without the additional costs associated with a rubber backing material, costs that include manufacturing costs and recycling costs.  
         [0019]    Metallocene is the general name for a family of catalysts that have been used in forming ultra low-density polyethylene (ULDPE) polymers. Two preferred metallocene catalyst materials are Exact, manufactured by Exxon, and Engage, manufactured by Pont Dow Elastomers.  
         [0020]    Table 1 below shows one preferred composition for the recyclable thermoplastic backing material  20  of FIG. 1.  
                                     TABLE 1                       INGREDIENT   DESCRIPTION   WEIGHT                                Ethylene-octene   Thermoplastic   25       copolymer formed using   copolymer (.885 density           metallocene catalyst   and 30 melt index)           Ethylene-octene   Thermoplastic   13.335       copolymer formed using   copolymer (.885 density           metallocene catalyst   and 3 melt index)           Paraffinic Oil   Plasticizer   3.75       Zinc Oxide   Additive   .4275       Heat Stabilizer   Additive   .30       Processing Aid   Additive   .15       Low Density   Thermoplastic Additive   1.5375       Polyethylene           Calcium Carbonate   Filler   55.5       (CaCO 3 )                  
 
         [0021]    While the ingredients as listed in Table 1 are shown in a particular order from top to bottom, it is likely that the order of addition of ingredients will not materially affect the composition of the backing material  20  to be formed as described below in FIG.  3 .  
         [0022]    Of course, one of ordinary skill in the art appreciates that the composition of the backing material  20  is merely representative of a potentially limitless variations in the material compositions based on ethylene-octene copolymers formed using metallocene catalyst and is not intended to be limiting. Further, other thermoplastic copolymers other than ethylene-octene, or other thermoplastic polymer or copolymer materials blended with the ethylene-octene copolymer, are specifically contemplated by the present invention as long as they meet the requirements of being recyclable and providing a rubber feeling and weighted backing material.  
         [0023]    [0023]FIG. 3 shows the process for forming the recyclable thermoplastic backing material  20 . The major ingredients for forming the recyclable thermoplastic backing material  20  as described in Table 1 above are first loaded into one or more loss in weight feeders  50 . Again, as described above, it is preferable that the ethylene-octene copolymer having the 30-melt index is added to the feeder  50  prior to introduction of the other major ingredients. The feeders  50  feed the raw materials into a continuous mixer  52 , which mixes the raw materials. The mixer  52  is coupled to an extruder  54 , which mixes, melts, and extrudes the raw materials in a method well known in the art. The extruded raw materials are then pelletized using an underwater pelletizer  56 , which is fed water from a tank (not shown) through a water pump  60 , therein forming pellets  61 . The pellets  61  are then introduced to a spin dryer  62 . The spun dry pellets  61  fall into a fluidized bed/dryer  64  to further dry the pellets. The pellets  61  then enter a cooler/classifier  66  that cools the pellets  61  and separates the pellets  61  by size. The sized pellets  61  are then sent to a silo  68  for storage. The silo is maintained below about 25 degrees Celsius (about 80 degrees Fahrenheit) to prevent the pellets  61  from sticking together. The sized pellets  61  are then available to form the throw-in mat as described below in FIG. 3.  
         [0024]    Referring now to FIG. 4, the sized pellets  61  are introduced, or fed, to an extruder  70  for melting. The melted pellets  61  then enter a die  72 , which forces the material out at the bottom  74  at a desired thickness. Preferably, the temperature of the melted pellets  61  is approximately 165 to 185 degrees Celsius, and more preferably about 175 degrees Celsius (350 degrees Fahrenheit), as it exits the bottom  74  of the die  72 . A feed roll  76  containing the primary backing layer  12  coupled to the carpet pile  18  is unrolled and closely coupled to the die  72 . The melted pellet  61  material is pressed to the second side  16  of the primary backing layer  12  between a pressure roll  80  and a chill roll  82  and rolled onto a roller  84 . The rolls  80 ,  82  apply sufficient pressure to adhere the recyclable thermoplastic backing material  20  to the primary backing layer  12 .  
         [0025]    As shown in FIG. 5, the rolled material  87  is then cut to an appropriate size and placed in a mat press  88 . The rolled material  87  then molded under heat and pressure for a sufficient period of time to allow the thermoplastic backing material  20  to flow to form the desired shape. As one of ordinary skill in the art recognizes, the amount of heat, pressure and time may be varied depending upon the composition of the thermoplastic backing material and the desired surface quality. Normal pressings of 20-25 tons at approximately 155 and 175 degrees Celsius, and more preferably at about 165 degrees Celsius (approximately 330 degrees Fahrenheit), for about 20 seconds are used to flow the thermoplastic backing material having a composition as shown in Table 1.  
         [0026]    By modifying the mold itself, the pressing process can also form the nibs  26  and grooves  22  on the bottom surface of the recyclable thermoplastic backing material  20 .  
         [0027]    When the cycle is complete, the rolled material  87  is removed and placed into a cold press  94 , where pressure is applied to cool the material, therein forming the throw in mat  10 . The mat  10  is removed from the cold press  94  and may be subsequently trimmed to a desired shape.  
         [0028]    Table 2 below illustrates the various performance characteristics of throw in mats  10  made with made with Shiva and Paramount carpet pile  18  material in accordance with the present invention.  
                                                     TABLE 2                                   PARAMOUNT   SHIVA WITH 52                   WITH 52 OZ.   OZ.                   THERMOPLASTIC   THERMOPLASTIC           CLASSIFICATION   SPECIFICATION   BACKING   BACKING       TEST   CRITERIA   LIMITS   MATERIAL   MATERIAL                                Shrink   %   +/−2     0.00   0.00       Water MD           Shrink   %   +/−2     0.00   0.00       Water AMD           Shrink   %   +/−2     0.40   0.75       Heat MD           Shrink   %   +/−2     0.00   0.00       Heat AMD           Dim Stab   %   +/−2     0.40   0.40       Exp/Cont           MD           Dim Stab   %   +/−2     0.20   0.25       Exp/Cont           AMD           Tensile Str   Newtons   400 MIN   869.40   888.60       MD           Tensile Str   Newtons   400 MIN   766.38   792.88       AMD           Tensile Str   Newtons   400 MIN   926.80   913.80       Imrsd MD           Tensile Str   Newtons   400 MIN   769.38   736.88       Imrsd AMD           Tensile aft   % Change   80%   100.64   93.18       112.8 kJ %           Of Orig MD           Tensile aft   % Change   80%   92.02   89.91       112.8 kJ %           Of Orig           AMD           Tensile aft   Newtons   RESULTS   857.00   828.00       112.8 kJ MD           Tensile aft   Newtons   RESULTS   705.25   712.88       112.8 kJ           AMD           Trap Tear   Newtons   90   255.80   270.40       MD           Trap Tear   Newtons   50   201.00   197.60       AMD           Trap Tear   Newtons   90   272.80   282.20       Imrsd MD           Trap Tear   Newtons   50   215.60   203.00       Imrsd           AMD           Tuft Bind   Newton   16   20.79   20.31       Orig           Tuft Bind   Newton   10   21.80   15.49       H/A           Adh   N/mm   +/−0.96   Can&#39;t Separate   Can&#39;t Separate       Cpt/Mat           Orig MD           Adh   N/mm   +/−0.96   Can&#39;t Separate   Can&#39;t Separate       Cpt/Mat           Orig AMD           Adh   N/mm   +/−0.96   Can&#39;t Separate   Can&#39;t Separate       Cpt/Mat           Imrsd MD           Adh   N/mm   +/−0.96   Can&#39;t Separate   Can&#39;t Separate       Cpt/Mat           Imrsd AMD           Adh   N/mm   +/−0.96   Can&#39;t Separate   Can&#39;t Separate       Cpt/Mat           Cyc MD           Adh   N/mm   +/−0.96   Can&#39;t Separate   Can&#39;t Separate       Cpt/Mat           Cyc AMD           Cld Resist   Rate   Satisfactory?   Satisfactory   Satisfactory       H/A FF MD           Cld Resist   Rate   Satisfactory?   Satisfactory   Satisfactory       H/A FF           AMD           Cld Resist   Rate   Satisfactory?   Satisfactory   Satisfactory       Orig FF MD           Cld Resist   Rate   Satisfactory?   Satisfactory   Satisfactory       Orig FF           AMD           Abr H18   Cycles   2000   2000.00   2000.00       1000 g           2000 c           Fiber Loss   Grams   0.2   0.07   0.18       H18 1000 g            300 c           Heat Aging @   Rate    4 MIN   5.00   5.00       90° C.           Flam MD   mm/min   100 MAX   47.80   41.70       Flam AMD   mm/min   100 MAX   36.60   25.40       Breaking   Newton   330   904.20   895.40       Strength           MD           Breaking   Newton   330   741.88   765.00       Strength           AMD           Tongue   Newton   53.4   72.32   71.98       Tear MD           Tongue   Newton   53.4   89.88   96.32       Tear AMD           Resist   gm   0.2   0.02   0.03       Beard/Fuzz           H18           Abr H18   Cycles   RESULTS   3900.00   9525.00       1000 g           Failure           Nib Wear   Rate   Satisfactory?   Satisfactory   Satisfactory       MD           Nib Wear   Rate   Satisfactory?   Satisfactory   Satisfactory       AMD                  
 
         [0029]    The throw-in mats of the present invention offer many advantages over throw in mats  10  of the prior art. For example, the thermoplastic backing material  20  of the throw-in mats  10  is recyclable. This limits manufacturing costs in terms of waste removal and can help to minimize raw material costs. Second, the throw-in mats  10  have the look and feel of rubber at a cost savings in terms of manufacture and raw material costs over rubber. Third, the thermoplastic backing material does not require a latex backing layer in order to adhere the backing material to the primary backing layer. Fourth, the throw-in mats  10  are relatively easy and cost-effective to manufacture.  
         [0030]    While the invention has been described in terms of preferred embodiments, it will be understood, of course, that the invention is not limited thereto since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings.